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authorroot <root@artemis.panaceas.org>2015-12-25 04:40:36 +0000
committerroot <root@artemis.panaceas.org>2015-12-25 04:40:36 +0000
commit849369d6c66d3054688672f97d31fceb8e8230fb (patch)
tree6135abc790ca67dedbe07c39806591e70eda81ce /drivers/xen
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initial_commit
Diffstat (limited to 'drivers/xen')
-rw-r--r--drivers/xen/Kconfig108
-rw-r--r--drivers/xen/Makefile25
-rw-r--r--drivers/xen/balloon.c476
-rw-r--r--drivers/xen/biomerge.c13
-rw-r--r--drivers/xen/cpu_hotplug.c111
-rw-r--r--drivers/xen/events.c1698
-rw-r--r--drivers/xen/evtchn.c560
-rw-r--r--drivers/xen/features.c33
-rw-r--r--drivers/xen/gntalloc.c555
-rw-r--r--drivers/xen/gntdev.c765
-rw-r--r--drivers/xen/grant-table.c690
-rw-r--r--drivers/xen/manage.c337
-rw-r--r--drivers/xen/pci.c117
-rw-r--r--drivers/xen/platform-pci.c197
-rw-r--r--drivers/xen/swiotlb-xen.c522
-rw-r--r--drivers/xen/sys-hypervisor.c447
-rw-r--r--drivers/xen/tmem.c264
-rw-r--r--drivers/xen/xen-balloon.c256
-rw-r--r--drivers/xen/xenbus/Makefile12
-rw-r--r--drivers/xen/xenbus/xenbus_client.c613
-rw-r--r--drivers/xen/xenbus/xenbus_comms.c234
-rw-r--r--drivers/xen/xenbus/xenbus_comms.h46
-rw-r--r--drivers/xen/xenbus/xenbus_probe.c786
-rw-r--r--drivers/xen/xenbus/xenbus_probe.h78
-rw-r--r--drivers/xen/xenbus/xenbus_probe_backend.c276
-rw-r--r--drivers/xen/xenbus/xenbus_probe_frontend.c338
-rw-r--r--drivers/xen/xenbus/xenbus_xs.c907
-rw-r--r--drivers/xen/xencomm.c217
-rw-r--r--drivers/xen/xenfs/Makefile4
-rw-r--r--drivers/xen/xenfs/privcmd.c400
-rw-r--r--drivers/xen/xenfs/super.c137
-rw-r--r--drivers/xen/xenfs/xenbus.c593
-rw-r--r--drivers/xen/xenfs/xenfs.h9
-rw-r--r--drivers/xen/xenfs/xenstored.c68
34 files changed, 11892 insertions, 0 deletions
diff --git a/drivers/xen/Kconfig b/drivers/xen/Kconfig
new file mode 100644
index 00000000..a59638b3
--- /dev/null
+++ b/drivers/xen/Kconfig
@@ -0,0 +1,108 @@
+menu "Xen driver support"
+ depends on XEN
+
+config XEN_BALLOON
+ bool "Xen memory balloon driver"
+ default y
+ help
+ The balloon driver allows the Xen domain to request more memory from
+ the system to expand the domain's memory allocation, or alternatively
+ return unneeded memory to the system.
+
+config XEN_SCRUB_PAGES
+ bool "Scrub pages before returning them to system"
+ depends on XEN_BALLOON
+ default y
+ help
+ Scrub pages before returning them to the system for reuse by
+ other domains. This makes sure that any confidential data
+ is not accidentally visible to other domains. Is it more
+ secure, but slightly less efficient.
+ If in doubt, say yes.
+
+config XEN_DEV_EVTCHN
+ tristate "Xen /dev/xen/evtchn device"
+ default y
+ help
+ The evtchn driver allows a userspace process to triger event
+ channels and to receive notification of an event channel
+ firing.
+ If in doubt, say yes.
+
+config XEN_BACKEND
+ bool "Backend driver support"
+ depends on XEN_DOM0
+ default y
+ help
+ Support for backend device drivers that provide I/O services
+ to other virtual machines.
+
+config XENFS
+ tristate "Xen filesystem"
+ default y
+ help
+ The xen filesystem provides a way for domains to share
+ information with each other and with the hypervisor.
+ For example, by reading and writing the "xenbus" file, guests
+ may pass arbitrary information to the initial domain.
+ If in doubt, say yes.
+
+config XEN_COMPAT_XENFS
+ bool "Create compatibility mount point /proc/xen"
+ depends on XENFS
+ default y
+ help
+ The old xenstore userspace tools expect to find "xenbus"
+ under /proc/xen, but "xenbus" is now found at the root of the
+ xenfs filesystem. Selecting this causes the kernel to create
+ the compatibility mount point /proc/xen if it is running on
+ a xen platform.
+ If in doubt, say yes.
+
+config XEN_SYS_HYPERVISOR
+ bool "Create xen entries under /sys/hypervisor"
+ depends on SYSFS
+ select SYS_HYPERVISOR
+ default y
+ help
+ Create entries under /sys/hypervisor describing the Xen
+ hypervisor environment. When running native or in another
+ virtual environment, /sys/hypervisor will still be present,
+ but will have no xen contents.
+
+config XEN_XENBUS_FRONTEND
+ tristate
+
+config XEN_GNTDEV
+ tristate "userspace grant access device driver"
+ depends on XEN
+ default m
+ select MMU_NOTIFIER
+ help
+ Allows userspace processes to use grants.
+
+config XEN_GRANT_DEV_ALLOC
+ tristate "User-space grant reference allocator driver"
+ depends on XEN
+ default m
+ help
+ Allows userspace processes to create pages with access granted
+ to other domains. This can be used to implement frontend drivers
+ or as part of an inter-domain shared memory channel.
+
+config XEN_PLATFORM_PCI
+ tristate "xen platform pci device driver"
+ depends on XEN_PVHVM && PCI
+ default m
+ help
+ Driver for the Xen PCI Platform device: it is responsible for
+ initializing xenbus and grant_table when running in a Xen HVM
+ domain. As a consequence this driver is required to run any Xen PV
+ frontend on Xen HVM.
+
+config SWIOTLB_XEN
+ def_bool y
+ depends on PCI
+ select SWIOTLB
+
+endmenu
diff --git a/drivers/xen/Makefile b/drivers/xen/Makefile
new file mode 100644
index 00000000..bbc18258
--- /dev/null
+++ b/drivers/xen/Makefile
@@ -0,0 +1,25 @@
+obj-y += grant-table.o features.o events.o manage.o balloon.o
+obj-y += xenbus/
+obj-y += tmem.o
+
+nostackp := $(call cc-option, -fno-stack-protector)
+CFLAGS_features.o := $(nostackp)
+
+obj-$(CONFIG_BLOCK) += biomerge.o
+obj-$(CONFIG_HOTPLUG_CPU) += cpu_hotplug.o
+obj-$(CONFIG_XEN_XENCOMM) += xencomm.o
+obj-$(CONFIG_XEN_BALLOON) += xen-balloon.o
+obj-$(CONFIG_XEN_DEV_EVTCHN) += xen-evtchn.o
+obj-$(CONFIG_XEN_GNTDEV) += xen-gntdev.o
+obj-$(CONFIG_XEN_GRANT_DEV_ALLOC) += xen-gntalloc.o
+obj-$(CONFIG_XENFS) += xenfs/
+obj-$(CONFIG_XEN_SYS_HYPERVISOR) += sys-hypervisor.o
+obj-$(CONFIG_XEN_PLATFORM_PCI) += xen-platform-pci.o
+obj-$(CONFIG_SWIOTLB_XEN) += swiotlb-xen.o
+obj-$(CONFIG_XEN_DOM0) += pci.o
+
+xen-evtchn-y := evtchn.o
+xen-gntdev-y := gntdev.o
+xen-gntalloc-y := gntalloc.o
+
+xen-platform-pci-y := platform-pci.o
diff --git a/drivers/xen/balloon.c b/drivers/xen/balloon.c
new file mode 100644
index 00000000..f54290ba
--- /dev/null
+++ b/drivers/xen/balloon.c
@@ -0,0 +1,476 @@
+/******************************************************************************
+ * Xen balloon driver - enables returning/claiming memory to/from Xen.
+ *
+ * Copyright (c) 2003, B Dragovic
+ * Copyright (c) 2003-2004, M Williamson, K Fraser
+ * Copyright (c) 2005 Dan M. Smith, IBM Corporation
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation; or, when distributed
+ * separately from the Linux kernel or incorporated into other
+ * software packages, subject to the following license:
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this source file (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use, copy, modify,
+ * merge, publish, distribute, sublicense, and/or sell copies of the Software,
+ * and to permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/errno.h>
+#include <linux/mm.h>
+#include <linux/bootmem.h>
+#include <linux/pagemap.h>
+#include <linux/highmem.h>
+#include <linux/mutex.h>
+#include <linux/list.h>
+#include <linux/gfp.h>
+
+#include <asm/page.h>
+#include <asm/pgalloc.h>
+#include <asm/pgtable.h>
+#include <asm/tlb.h>
+#include <asm/e820.h>
+
+#include <asm/xen/hypervisor.h>
+#include <asm/xen/hypercall.h>
+
+#include <xen/xen.h>
+#include <xen/interface/xen.h>
+#include <xen/interface/memory.h>
+#include <xen/balloon.h>
+#include <xen/features.h>
+#include <xen/page.h>
+
+/*
+ * balloon_process() state:
+ *
+ * BP_DONE: done or nothing to do,
+ * BP_EAGAIN: error, go to sleep,
+ * BP_ECANCELED: error, balloon operation canceled.
+ */
+
+enum bp_state {
+ BP_DONE,
+ BP_EAGAIN,
+ BP_ECANCELED
+};
+
+
+static DEFINE_MUTEX(balloon_mutex);
+
+struct balloon_stats balloon_stats;
+EXPORT_SYMBOL_GPL(balloon_stats);
+
+/* We increase/decrease in batches which fit in a page */
+static unsigned long frame_list[PAGE_SIZE / sizeof(unsigned long)];
+
+#ifdef CONFIG_HIGHMEM
+#define inc_totalhigh_pages() (totalhigh_pages++)
+#define dec_totalhigh_pages() (totalhigh_pages--)
+#else
+#define inc_totalhigh_pages() do {} while(0)
+#define dec_totalhigh_pages() do {} while(0)
+#endif
+
+/* List of ballooned pages, threaded through the mem_map array. */
+static LIST_HEAD(ballooned_pages);
+
+/* Main work function, always executed in process context. */
+static void balloon_process(struct work_struct *work);
+static DECLARE_DELAYED_WORK(balloon_worker, balloon_process);
+
+/* When ballooning out (allocating memory to return to Xen) we don't really
+ want the kernel to try too hard since that can trigger the oom killer. */
+#define GFP_BALLOON \
+ (GFP_HIGHUSER | __GFP_NOWARN | __GFP_NORETRY | __GFP_NOMEMALLOC)
+
+static void scrub_page(struct page *page)
+{
+#ifdef CONFIG_XEN_SCRUB_PAGES
+ clear_highpage(page);
+#endif
+}
+
+/* balloon_append: add the given page to the balloon. */
+static void __balloon_append(struct page *page)
+{
+ /* Lowmem is re-populated first, so highmem pages go at list tail. */
+ if (PageHighMem(page)) {
+ list_add_tail(&page->lru, &ballooned_pages);
+ balloon_stats.balloon_high++;
+ } else {
+ list_add(&page->lru, &ballooned_pages);
+ balloon_stats.balloon_low++;
+ }
+}
+
+static void balloon_append(struct page *page)
+{
+ __balloon_append(page);
+ if (PageHighMem(page))
+ dec_totalhigh_pages();
+ totalram_pages--;
+}
+
+/* balloon_retrieve: rescue a page from the balloon, if it is not empty. */
+static struct page *balloon_retrieve(bool prefer_highmem)
+{
+ struct page *page;
+
+ if (list_empty(&ballooned_pages))
+ return NULL;
+
+ if (prefer_highmem)
+ page = list_entry(ballooned_pages.prev, struct page, lru);
+ else
+ page = list_entry(ballooned_pages.next, struct page, lru);
+ list_del(&page->lru);
+
+ if (PageHighMem(page)) {
+ balloon_stats.balloon_high--;
+ inc_totalhigh_pages();
+ }
+ else
+ balloon_stats.balloon_low--;
+
+ totalram_pages++;
+
+ return page;
+}
+
+static struct page *balloon_first_page(void)
+{
+ if (list_empty(&ballooned_pages))
+ return NULL;
+ return list_entry(ballooned_pages.next, struct page, lru);
+}
+
+static struct page *balloon_next_page(struct page *page)
+{
+ struct list_head *next = page->lru.next;
+ if (next == &ballooned_pages)
+ return NULL;
+ return list_entry(next, struct page, lru);
+}
+
+static enum bp_state update_schedule(enum bp_state state)
+{
+ if (state == BP_DONE) {
+ balloon_stats.schedule_delay = 1;
+ balloon_stats.retry_count = 1;
+ return BP_DONE;
+ }
+
+ ++balloon_stats.retry_count;
+
+ if (balloon_stats.max_retry_count != RETRY_UNLIMITED &&
+ balloon_stats.retry_count > balloon_stats.max_retry_count) {
+ balloon_stats.schedule_delay = 1;
+ balloon_stats.retry_count = 1;
+ return BP_ECANCELED;
+ }
+
+ balloon_stats.schedule_delay <<= 1;
+
+ if (balloon_stats.schedule_delay > balloon_stats.max_schedule_delay)
+ balloon_stats.schedule_delay = balloon_stats.max_schedule_delay;
+
+ return BP_EAGAIN;
+}
+
+static long current_credit(void)
+{
+ unsigned long target = balloon_stats.target_pages;
+
+ target = min(target,
+ balloon_stats.current_pages +
+ balloon_stats.balloon_low +
+ balloon_stats.balloon_high);
+
+ return target - balloon_stats.current_pages;
+}
+
+static enum bp_state increase_reservation(unsigned long nr_pages)
+{
+ int rc;
+ unsigned long pfn, i;
+ struct page *page;
+ struct xen_memory_reservation reservation = {
+ .address_bits = 0,
+ .extent_order = 0,
+ .domid = DOMID_SELF
+ };
+
+ if (nr_pages > ARRAY_SIZE(frame_list))
+ nr_pages = ARRAY_SIZE(frame_list);
+
+ page = balloon_first_page();
+ for (i = 0; i < nr_pages; i++) {
+ if (!page) {
+ nr_pages = i;
+ break;
+ }
+ frame_list[i] = page_to_pfn(page);
+ page = balloon_next_page(page);
+ }
+
+ set_xen_guest_handle(reservation.extent_start, frame_list);
+ reservation.nr_extents = nr_pages;
+ rc = HYPERVISOR_memory_op(XENMEM_populate_physmap, &reservation);
+ if (rc <= 0)
+ return BP_EAGAIN;
+
+ for (i = 0; i < rc; i++) {
+ page = balloon_retrieve(false);
+ BUG_ON(page == NULL);
+
+ pfn = page_to_pfn(page);
+ BUG_ON(!xen_feature(XENFEAT_auto_translated_physmap) &&
+ phys_to_machine_mapping_valid(pfn));
+
+ set_phys_to_machine(pfn, frame_list[i]);
+
+ /* Link back into the page tables if not highmem. */
+ if (xen_pv_domain() && !PageHighMem(page)) {
+ int ret;
+ ret = HYPERVISOR_update_va_mapping(
+ (unsigned long)__va(pfn << PAGE_SHIFT),
+ mfn_pte(frame_list[i], PAGE_KERNEL),
+ 0);
+ BUG_ON(ret);
+ }
+
+ /* Relinquish the page back to the allocator. */
+ ClearPageReserved(page);
+ init_page_count(page);
+ __free_page(page);
+ }
+
+ balloon_stats.current_pages += rc;
+
+ return BP_DONE;
+}
+
+static enum bp_state decrease_reservation(unsigned long nr_pages, gfp_t gfp)
+{
+ enum bp_state state = BP_DONE;
+ unsigned long pfn, i;
+ struct page *page;
+ int ret;
+ struct xen_memory_reservation reservation = {
+ .address_bits = 0,
+ .extent_order = 0,
+ .domid = DOMID_SELF
+ };
+
+ if (nr_pages > ARRAY_SIZE(frame_list))
+ nr_pages = ARRAY_SIZE(frame_list);
+
+ for (i = 0; i < nr_pages; i++) {
+ if ((page = alloc_page(gfp)) == NULL) {
+ nr_pages = i;
+ state = BP_EAGAIN;
+ break;
+ }
+
+ pfn = page_to_pfn(page);
+ frame_list[i] = pfn_to_mfn(pfn);
+
+ scrub_page(page);
+
+ if (xen_pv_domain() && !PageHighMem(page)) {
+ ret = HYPERVISOR_update_va_mapping(
+ (unsigned long)__va(pfn << PAGE_SHIFT),
+ __pte_ma(0), 0);
+ BUG_ON(ret);
+ }
+
+ }
+
+ /* Ensure that ballooned highmem pages don't have kmaps. */
+ kmap_flush_unused();
+ flush_tlb_all();
+
+ /* No more mappings: invalidate P2M and add to balloon. */
+ for (i = 0; i < nr_pages; i++) {
+ pfn = mfn_to_pfn(frame_list[i]);
+ __set_phys_to_machine(pfn, INVALID_P2M_ENTRY);
+ balloon_append(pfn_to_page(pfn));
+ }
+
+ set_xen_guest_handle(reservation.extent_start, frame_list);
+ reservation.nr_extents = nr_pages;
+ ret = HYPERVISOR_memory_op(XENMEM_decrease_reservation, &reservation);
+ BUG_ON(ret != nr_pages);
+
+ balloon_stats.current_pages -= nr_pages;
+
+ return state;
+}
+
+/*
+ * We avoid multiple worker processes conflicting via the balloon mutex.
+ * We may of course race updates of the target counts (which are protected
+ * by the balloon lock), or with changes to the Xen hard limit, but we will
+ * recover from these in time.
+ */
+static void balloon_process(struct work_struct *work)
+{
+ enum bp_state state = BP_DONE;
+ long credit;
+
+ mutex_lock(&balloon_mutex);
+
+ do {
+ credit = current_credit();
+
+ if (credit > 0)
+ state = increase_reservation(credit);
+
+ if (credit < 0)
+ state = decrease_reservation(-credit, GFP_BALLOON);
+
+ state = update_schedule(state);
+
+#ifndef CONFIG_PREEMPT
+ if (need_resched())
+ schedule();
+#endif
+ } while (credit && state == BP_DONE);
+
+ /* Schedule more work if there is some still to be done. */
+ if (state == BP_EAGAIN)
+ schedule_delayed_work(&balloon_worker, balloon_stats.schedule_delay * HZ);
+
+ mutex_unlock(&balloon_mutex);
+}
+
+/* Resets the Xen limit, sets new target, and kicks off processing. */
+void balloon_set_new_target(unsigned long target)
+{
+ /* No need for lock. Not read-modify-write updates. */
+ balloon_stats.target_pages = target;
+ schedule_delayed_work(&balloon_worker, 0);
+}
+EXPORT_SYMBOL_GPL(balloon_set_new_target);
+
+/**
+ * alloc_xenballooned_pages - get pages that have been ballooned out
+ * @nr_pages: Number of pages to get
+ * @pages: pages returned
+ * @return 0 on success, error otherwise
+ */
+int alloc_xenballooned_pages(int nr_pages, struct page** pages)
+{
+ int pgno = 0;
+ struct page* page;
+ mutex_lock(&balloon_mutex);
+ while (pgno < nr_pages) {
+ page = balloon_retrieve(true);
+ if (page) {
+ pages[pgno++] = page;
+ } else {
+ enum bp_state st;
+ st = decrease_reservation(nr_pages - pgno, GFP_HIGHUSER);
+ if (st != BP_DONE)
+ goto out_undo;
+ }
+ }
+ mutex_unlock(&balloon_mutex);
+ return 0;
+ out_undo:
+ while (pgno)
+ balloon_append(pages[--pgno]);
+ /* Free the memory back to the kernel soon */
+ schedule_delayed_work(&balloon_worker, 0);
+ mutex_unlock(&balloon_mutex);
+ return -ENOMEM;
+}
+EXPORT_SYMBOL(alloc_xenballooned_pages);
+
+/**
+ * free_xenballooned_pages - return pages retrieved with get_ballooned_pages
+ * @nr_pages: Number of pages
+ * @pages: pages to return
+ */
+void free_xenballooned_pages(int nr_pages, struct page** pages)
+{
+ int i;
+
+ mutex_lock(&balloon_mutex);
+
+ for (i = 0; i < nr_pages; i++) {
+ if (pages[i])
+ balloon_append(pages[i]);
+ }
+
+ /* The balloon may be too large now. Shrink it if needed. */
+ if (current_credit())
+ schedule_delayed_work(&balloon_worker, 0);
+
+ mutex_unlock(&balloon_mutex);
+}
+EXPORT_SYMBOL(free_xenballooned_pages);
+
+static int __init balloon_init(void)
+{
+ unsigned long pfn, extra_pfn_end;
+ struct page *page;
+
+ if (!xen_domain())
+ return -ENODEV;
+
+ pr_info("xen/balloon: Initialising balloon driver.\n");
+
+ balloon_stats.current_pages = xen_pv_domain() ? min(xen_start_info->nr_pages, max_pfn) : max_pfn;
+ balloon_stats.target_pages = balloon_stats.current_pages;
+ balloon_stats.balloon_low = 0;
+ balloon_stats.balloon_high = 0;
+
+ balloon_stats.schedule_delay = 1;
+ balloon_stats.max_schedule_delay = 32;
+ balloon_stats.retry_count = 1;
+ balloon_stats.max_retry_count = RETRY_UNLIMITED;
+
+ /*
+ * Initialise the balloon with excess memory space. We need
+ * to make sure we don't add memory which doesn't exist or
+ * logically exist. The E820 map can be trimmed to be smaller
+ * than the amount of physical memory due to the mem= command
+ * line parameter. And if this is a 32-bit non-HIGHMEM kernel
+ * on a system with memory which requires highmem to access,
+ * don't try to use it.
+ */
+ extra_pfn_end = min(min(max_pfn, e820_end_of_ram_pfn()),
+ (unsigned long)PFN_DOWN(xen_extra_mem_start + xen_extra_mem_size));
+ for (pfn = PFN_UP(xen_extra_mem_start);
+ pfn < extra_pfn_end;
+ pfn++) {
+ page = pfn_to_page(pfn);
+ /* totalram_pages and totalhigh_pages do not include the boot-time
+ balloon extension, so don't subtract from it. */
+ __balloon_append(page);
+ }
+
+ return 0;
+}
+
+subsys_initcall(balloon_init);
+
+MODULE_LICENSE("GPL");
diff --git a/drivers/xen/biomerge.c b/drivers/xen/biomerge.c
new file mode 100644
index 00000000..ba6eda4b
--- /dev/null
+++ b/drivers/xen/biomerge.c
@@ -0,0 +1,13 @@
+#include <linux/bio.h>
+#include <linux/io.h>
+#include <xen/page.h>
+
+bool xen_biovec_phys_mergeable(const struct bio_vec *vec1,
+ const struct bio_vec *vec2)
+{
+ unsigned long mfn1 = pfn_to_mfn(page_to_pfn(vec1->bv_page));
+ unsigned long mfn2 = pfn_to_mfn(page_to_pfn(vec2->bv_page));
+
+ return __BIOVEC_PHYS_MERGEABLE(vec1, vec2) &&
+ ((mfn1 == mfn2) || ((mfn1+1) == mfn2));
+}
diff --git a/drivers/xen/cpu_hotplug.c b/drivers/xen/cpu_hotplug.c
new file mode 100644
index 00000000..14e2d995
--- /dev/null
+++ b/drivers/xen/cpu_hotplug.c
@@ -0,0 +1,111 @@
+#include <linux/notifier.h>
+
+#include <xen/xen.h>
+#include <xen/xenbus.h>
+
+#include <asm/xen/hypervisor.h>
+#include <asm/cpu.h>
+
+static void enable_hotplug_cpu(int cpu)
+{
+ if (!cpu_present(cpu))
+ arch_register_cpu(cpu);
+
+ set_cpu_present(cpu, true);
+}
+
+static void disable_hotplug_cpu(int cpu)
+{
+ if (cpu_present(cpu))
+ arch_unregister_cpu(cpu);
+
+ set_cpu_present(cpu, false);
+}
+
+static int vcpu_online(unsigned int cpu)
+{
+ int err;
+ char dir[32], state[32];
+
+ sprintf(dir, "cpu/%u", cpu);
+ err = xenbus_scanf(XBT_NIL, dir, "availability", "%s", state);
+ if (err != 1) {
+ printk(KERN_ERR "XENBUS: Unable to read cpu state\n");
+ return err;
+ }
+
+ if (strcmp(state, "online") == 0)
+ return 1;
+ else if (strcmp(state, "offline") == 0)
+ return 0;
+
+ printk(KERN_ERR "XENBUS: unknown state(%s) on CPU%d\n", state, cpu);
+ return -EINVAL;
+}
+static void vcpu_hotplug(unsigned int cpu)
+{
+ if (!cpu_possible(cpu))
+ return;
+
+ switch (vcpu_online(cpu)) {
+ case 1:
+ enable_hotplug_cpu(cpu);
+ break;
+ case 0:
+ (void)cpu_down(cpu);
+ disable_hotplug_cpu(cpu);
+ break;
+ default:
+ break;
+ }
+}
+
+static void handle_vcpu_hotplug_event(struct xenbus_watch *watch,
+ const char **vec, unsigned int len)
+{
+ unsigned int cpu;
+ char *cpustr;
+ const char *node = vec[XS_WATCH_PATH];
+
+ cpustr = strstr(node, "cpu/");
+ if (cpustr != NULL) {
+ sscanf(cpustr, "cpu/%u", &cpu);
+ vcpu_hotplug(cpu);
+ }
+}
+
+static int setup_cpu_watcher(struct notifier_block *notifier,
+ unsigned long event, void *data)
+{
+ int cpu;
+ static struct xenbus_watch cpu_watch = {
+ .node = "cpu",
+ .callback = handle_vcpu_hotplug_event};
+
+ (void)register_xenbus_watch(&cpu_watch);
+
+ for_each_possible_cpu(cpu) {
+ if (vcpu_online(cpu) == 0) {
+ (void)cpu_down(cpu);
+ set_cpu_present(cpu, false);
+ }
+ }
+
+ return NOTIFY_DONE;
+}
+
+static int __init setup_vcpu_hotplug_event(void)
+{
+ static struct notifier_block xsn_cpu = {
+ .notifier_call = setup_cpu_watcher };
+
+ if (!xen_pv_domain())
+ return -ENODEV;
+
+ register_xenstore_notifier(&xsn_cpu);
+
+ return 0;
+}
+
+arch_initcall(setup_vcpu_hotplug_event);
+
diff --git a/drivers/xen/events.c b/drivers/xen/events.c
new file mode 100644
index 00000000..a5493f8a
--- /dev/null
+++ b/drivers/xen/events.c
@@ -0,0 +1,1698 @@
+/*
+ * Xen event channels
+ *
+ * Xen models interrupts with abstract event channels. Because each
+ * domain gets 1024 event channels, but NR_IRQ is not that large, we
+ * must dynamically map irqs<->event channels. The event channels
+ * interface with the rest of the kernel by defining a xen interrupt
+ * chip. When an event is received, it is mapped to an irq and sent
+ * through the normal interrupt processing path.
+ *
+ * There are four kinds of events which can be mapped to an event
+ * channel:
+ *
+ * 1. Inter-domain notifications. This includes all the virtual
+ * device events, since they're driven by front-ends in another domain
+ * (typically dom0).
+ * 2. VIRQs, typically used for timers. These are per-cpu events.
+ * 3. IPIs.
+ * 4. PIRQs - Hardware interrupts.
+ *
+ * Jeremy Fitzhardinge <jeremy@xensource.com>, XenSource Inc, 2007
+ */
+
+#include <linux/linkage.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/module.h>
+#include <linux/string.h>
+#include <linux/bootmem.h>
+#include <linux/slab.h>
+#include <linux/irqnr.h>
+#include <linux/pci.h>
+
+#include <asm/desc.h>
+#include <asm/ptrace.h>
+#include <asm/irq.h>
+#include <asm/idle.h>
+#include <asm/io_apic.h>
+#include <asm/sync_bitops.h>
+#include <asm/xen/pci.h>
+#include <asm/xen/hypercall.h>
+#include <asm/xen/hypervisor.h>
+
+#include <xen/xen.h>
+#include <xen/hvm.h>
+#include <xen/xen-ops.h>
+#include <xen/events.h>
+#include <xen/interface/xen.h>
+#include <xen/interface/event_channel.h>
+#include <xen/interface/hvm/hvm_op.h>
+#include <xen/interface/hvm/params.h>
+
+/*
+ * This lock protects updates to the following mapping and reference-count
+ * arrays. The lock does not need to be acquired to read the mapping tables.
+ */
+static DEFINE_SPINLOCK(irq_mapping_update_lock);
+
+static LIST_HEAD(xen_irq_list_head);
+
+/* IRQ <-> VIRQ mapping. */
+static DEFINE_PER_CPU(int [NR_VIRQS], virq_to_irq) = {[0 ... NR_VIRQS-1] = -1};
+
+/* IRQ <-> IPI mapping */
+static DEFINE_PER_CPU(int [XEN_NR_IPIS], ipi_to_irq) = {[0 ... XEN_NR_IPIS-1] = -1};
+
+/* Interrupt types. */
+enum xen_irq_type {
+ IRQT_UNBOUND = 0,
+ IRQT_PIRQ,
+ IRQT_VIRQ,
+ IRQT_IPI,
+ IRQT_EVTCHN
+};
+
+/*
+ * Packed IRQ information:
+ * type - enum xen_irq_type
+ * event channel - irq->event channel mapping
+ * cpu - cpu this event channel is bound to
+ * index - type-specific information:
+ * PIRQ - vector, with MSB being "needs EIO", or physical IRQ of the HVM
+ * guest, or GSI (real passthrough IRQ) of the device.
+ * VIRQ - virq number
+ * IPI - IPI vector
+ * EVTCHN -
+ */
+struct irq_info
+{
+ struct list_head list;
+ enum xen_irq_type type; /* type */
+ unsigned irq;
+ unsigned short evtchn; /* event channel */
+ unsigned short cpu; /* cpu bound */
+
+ union {
+ unsigned short virq;
+ enum ipi_vector ipi;
+ struct {
+ unsigned short pirq;
+ unsigned short gsi;
+ unsigned char vector;
+ unsigned char flags;
+ uint16_t domid;
+ } pirq;
+ } u;
+};
+#define PIRQ_NEEDS_EOI (1 << 0)
+#define PIRQ_SHAREABLE (1 << 1)
+
+static int *evtchn_to_irq;
+
+static DEFINE_PER_CPU(unsigned long [NR_EVENT_CHANNELS/BITS_PER_LONG],
+ cpu_evtchn_mask);
+
+/* Xen will never allocate port zero for any purpose. */
+#define VALID_EVTCHN(chn) ((chn) != 0)
+
+static struct irq_chip xen_dynamic_chip;
+static struct irq_chip xen_percpu_chip;
+static struct irq_chip xen_pirq_chip;
+static void enable_dynirq(struct irq_data *data);
+static void disable_dynirq(struct irq_data *data);
+
+/* Get info for IRQ */
+static struct irq_info *info_for_irq(unsigned irq)
+{
+ return irq_get_handler_data(irq);
+}
+
+/* Constructors for packed IRQ information. */
+static void xen_irq_info_common_init(struct irq_info *info,
+ unsigned irq,
+ enum xen_irq_type type,
+ unsigned short evtchn,
+ unsigned short cpu)
+{
+
+ BUG_ON(info->type != IRQT_UNBOUND && info->type != type);
+
+ info->type = type;
+ info->irq = irq;
+ info->evtchn = evtchn;
+ info->cpu = cpu;
+
+ evtchn_to_irq[evtchn] = irq;
+}
+
+static void xen_irq_info_evtchn_init(unsigned irq,
+ unsigned short evtchn)
+{
+ struct irq_info *info = info_for_irq(irq);
+
+ xen_irq_info_common_init(info, irq, IRQT_EVTCHN, evtchn, 0);
+}
+
+static void xen_irq_info_ipi_init(unsigned cpu,
+ unsigned irq,
+ unsigned short evtchn,
+ enum ipi_vector ipi)
+{
+ struct irq_info *info = info_for_irq(irq);
+
+ xen_irq_info_common_init(info, irq, IRQT_IPI, evtchn, 0);
+
+ info->u.ipi = ipi;
+
+ per_cpu(ipi_to_irq, cpu)[ipi] = irq;
+}
+
+static void xen_irq_info_virq_init(unsigned cpu,
+ unsigned irq,
+ unsigned short evtchn,
+ unsigned short virq)
+{
+ struct irq_info *info = info_for_irq(irq);
+
+ xen_irq_info_common_init(info, irq, IRQT_VIRQ, evtchn, 0);
+
+ info->u.virq = virq;
+
+ per_cpu(virq_to_irq, cpu)[virq] = irq;
+}
+
+static void xen_irq_info_pirq_init(unsigned irq,
+ unsigned short evtchn,
+ unsigned short pirq,
+ unsigned short gsi,
+ unsigned short vector,
+ uint16_t domid,
+ unsigned char flags)
+{
+ struct irq_info *info = info_for_irq(irq);
+
+ xen_irq_info_common_init(info, irq, IRQT_PIRQ, evtchn, 0);
+
+ info->u.pirq.pirq = pirq;
+ info->u.pirq.gsi = gsi;
+ info->u.pirq.vector = vector;
+ info->u.pirq.domid = domid;
+ info->u.pirq.flags = flags;
+}
+
+/*
+ * Accessors for packed IRQ information.
+ */
+static unsigned int evtchn_from_irq(unsigned irq)
+{
+ if (unlikely(WARN(irq < 0 || irq >= nr_irqs, "Invalid irq %d!\n", irq)))
+ return 0;
+
+ return info_for_irq(irq)->evtchn;
+}
+
+unsigned irq_from_evtchn(unsigned int evtchn)
+{
+ return evtchn_to_irq[evtchn];
+}
+EXPORT_SYMBOL_GPL(irq_from_evtchn);
+
+static enum ipi_vector ipi_from_irq(unsigned irq)
+{
+ struct irq_info *info = info_for_irq(irq);
+
+ BUG_ON(info == NULL);
+ BUG_ON(info->type != IRQT_IPI);
+
+ return info->u.ipi;
+}
+
+static unsigned virq_from_irq(unsigned irq)
+{
+ struct irq_info *info = info_for_irq(irq);
+
+ BUG_ON(info == NULL);
+ BUG_ON(info->type != IRQT_VIRQ);
+
+ return info->u.virq;
+}
+
+static unsigned pirq_from_irq(unsigned irq)
+{
+ struct irq_info *info = info_for_irq(irq);
+
+ BUG_ON(info == NULL);
+ BUG_ON(info->type != IRQT_PIRQ);
+
+ return info->u.pirq.pirq;
+}
+
+static enum xen_irq_type type_from_irq(unsigned irq)
+{
+ return info_for_irq(irq)->type;
+}
+
+static unsigned cpu_from_irq(unsigned irq)
+{
+ return info_for_irq(irq)->cpu;
+}
+
+static unsigned int cpu_from_evtchn(unsigned int evtchn)
+{
+ int irq = evtchn_to_irq[evtchn];
+ unsigned ret = 0;
+
+ if (irq != -1)
+ ret = cpu_from_irq(irq);
+
+ return ret;
+}
+
+static bool pirq_needs_eoi(unsigned irq)
+{
+ struct irq_info *info = info_for_irq(irq);
+
+ BUG_ON(info->type != IRQT_PIRQ);
+
+ return info->u.pirq.flags & PIRQ_NEEDS_EOI;
+}
+
+static inline unsigned long active_evtchns(unsigned int cpu,
+ struct shared_info *sh,
+ unsigned int idx)
+{
+ return (sh->evtchn_pending[idx] &
+ per_cpu(cpu_evtchn_mask, cpu)[idx] &
+ ~sh->evtchn_mask[idx]);
+}
+
+static void bind_evtchn_to_cpu(unsigned int chn, unsigned int cpu)
+{
+ int irq = evtchn_to_irq[chn];
+
+ BUG_ON(irq == -1);
+#ifdef CONFIG_SMP
+ cpumask_copy(irq_to_desc(irq)->irq_data.affinity, cpumask_of(cpu));
+#endif
+
+ clear_bit(chn, per_cpu(cpu_evtchn_mask, cpu_from_irq(irq)));
+ set_bit(chn, per_cpu(cpu_evtchn_mask, cpu));
+
+ info_for_irq(irq)->cpu = cpu;
+}
+
+static void init_evtchn_cpu_bindings(void)
+{
+ int i;
+#ifdef CONFIG_SMP
+ struct irq_info *info;
+
+ /* By default all event channels notify CPU#0. */
+ list_for_each_entry(info, &xen_irq_list_head, list) {
+ struct irq_desc *desc = irq_to_desc(info->irq);
+ cpumask_copy(desc->irq_data.affinity, cpumask_of(0));
+ }
+#endif
+
+ for_each_possible_cpu(i)
+ memset(per_cpu(cpu_evtchn_mask, i),
+ (i == 0) ? ~0 : 0, sizeof(*per_cpu(cpu_evtchn_mask, i)));
+}
+
+static inline void clear_evtchn(int port)
+{
+ struct shared_info *s = HYPERVISOR_shared_info;
+ sync_clear_bit(port, &s->evtchn_pending[0]);
+}
+
+static inline void set_evtchn(int port)
+{
+ struct shared_info *s = HYPERVISOR_shared_info;
+ sync_set_bit(port, &s->evtchn_pending[0]);
+}
+
+static inline int test_evtchn(int port)
+{
+ struct shared_info *s = HYPERVISOR_shared_info;
+ return sync_test_bit(port, &s->evtchn_pending[0]);
+}
+
+
+/**
+ * notify_remote_via_irq - send event to remote end of event channel via irq
+ * @irq: irq of event channel to send event to
+ *
+ * Unlike notify_remote_via_evtchn(), this is safe to use across
+ * save/restore. Notifications on a broken connection are silently
+ * dropped.
+ */
+void notify_remote_via_irq(int irq)
+{
+ int evtchn = evtchn_from_irq(irq);
+
+ if (VALID_EVTCHN(evtchn))
+ notify_remote_via_evtchn(evtchn);
+}
+EXPORT_SYMBOL_GPL(notify_remote_via_irq);
+
+static void mask_evtchn(int port)
+{
+ struct shared_info *s = HYPERVISOR_shared_info;
+ sync_set_bit(port, &s->evtchn_mask[0]);
+}
+
+static void unmask_evtchn(int port)
+{
+ struct shared_info *s = HYPERVISOR_shared_info;
+ unsigned int cpu = get_cpu();
+
+ BUG_ON(!irqs_disabled());
+
+ /* Slow path (hypercall) if this is a non-local port. */
+ if (unlikely(cpu != cpu_from_evtchn(port))) {
+ struct evtchn_unmask unmask = { .port = port };
+ (void)HYPERVISOR_event_channel_op(EVTCHNOP_unmask, &unmask);
+ } else {
+ struct vcpu_info *vcpu_info = __this_cpu_read(xen_vcpu);
+
+ sync_clear_bit(port, &s->evtchn_mask[0]);
+
+ /*
+ * The following is basically the equivalent of
+ * 'hw_resend_irq'. Just like a real IO-APIC we 'lose
+ * the interrupt edge' if the channel is masked.
+ */
+ if (sync_test_bit(port, &s->evtchn_pending[0]) &&
+ !sync_test_and_set_bit(port / BITS_PER_LONG,
+ &vcpu_info->evtchn_pending_sel))
+ vcpu_info->evtchn_upcall_pending = 1;
+ }
+
+ put_cpu();
+}
+
+static void xen_irq_init(unsigned irq)
+{
+ struct irq_info *info;
+#ifdef CONFIG_SMP
+ struct irq_desc *desc = irq_to_desc(irq);
+
+ /* By default all event channels notify CPU#0. */
+ cpumask_copy(desc->irq_data.affinity, cpumask_of(0));
+#endif
+
+ info = kzalloc(sizeof(*info), GFP_KERNEL);
+ if (info == NULL)
+ panic("Unable to allocate metadata for IRQ%d\n", irq);
+
+ info->type = IRQT_UNBOUND;
+
+ irq_set_handler_data(irq, info);
+
+ list_add_tail(&info->list, &xen_irq_list_head);
+}
+
+static int __must_check xen_allocate_irq_dynamic(void)
+{
+ int first = 0;
+ int irq;
+
+#ifdef CONFIG_X86_IO_APIC
+ /*
+ * For an HVM guest or domain 0 which see "real" (emulated or
+ * actual respectively) GSIs we allocate dynamic IRQs
+ * e.g. those corresponding to event channels or MSIs
+ * etc. from the range above those "real" GSIs to avoid
+ * collisions.
+ */
+ if (xen_initial_domain() || xen_hvm_domain())
+ first = get_nr_irqs_gsi();
+#endif
+
+ irq = irq_alloc_desc_from(first, -1);
+
+ xen_irq_init(irq);
+
+ return irq;
+}
+
+static int __must_check xen_allocate_irq_gsi(unsigned gsi)
+{
+ int irq;
+
+ /*
+ * A PV guest has no concept of a GSI (since it has no ACPI
+ * nor access to/knowledge of the physical APICs). Therefore
+ * all IRQs are dynamically allocated from the entire IRQ
+ * space.
+ */
+ if (xen_pv_domain() && !xen_initial_domain())
+ return xen_allocate_irq_dynamic();
+
+ /* Legacy IRQ descriptors are already allocated by the arch. */
+ if (gsi < NR_IRQS_LEGACY)
+ irq = gsi;
+ else
+ irq = irq_alloc_desc_at(gsi, -1);
+
+ xen_irq_init(irq);
+
+ return irq;
+}
+
+static void xen_free_irq(unsigned irq)
+{
+ struct irq_info *info = irq_get_handler_data(irq);
+
+ list_del(&info->list);
+
+ irq_set_handler_data(irq, NULL);
+
+ kfree(info);
+
+ /* Legacy IRQ descriptors are managed by the arch. */
+ if (irq < NR_IRQS_LEGACY)
+ return;
+
+ irq_free_desc(irq);
+}
+
+static void pirq_query_unmask(int irq)
+{
+ struct physdev_irq_status_query irq_status;
+ struct irq_info *info = info_for_irq(irq);
+
+ BUG_ON(info->type != IRQT_PIRQ);
+
+ irq_status.irq = pirq_from_irq(irq);
+ if (HYPERVISOR_physdev_op(PHYSDEVOP_irq_status_query, &irq_status))
+ irq_status.flags = 0;
+
+ info->u.pirq.flags &= ~PIRQ_NEEDS_EOI;
+ if (irq_status.flags & XENIRQSTAT_needs_eoi)
+ info->u.pirq.flags |= PIRQ_NEEDS_EOI;
+}
+
+static bool probing_irq(int irq)
+{
+ struct irq_desc *desc = irq_to_desc(irq);
+
+ return desc && desc->action == NULL;
+}
+
+static void eoi_pirq(struct irq_data *data)
+{
+ int evtchn = evtchn_from_irq(data->irq);
+ struct physdev_eoi eoi = { .irq = pirq_from_irq(data->irq) };
+ int rc = 0;
+
+ irq_move_irq(data);
+
+ if (VALID_EVTCHN(evtchn))
+ clear_evtchn(evtchn);
+
+ if (pirq_needs_eoi(data->irq)) {
+ rc = HYPERVISOR_physdev_op(PHYSDEVOP_eoi, &eoi);
+ WARN_ON(rc);
+ }
+}
+
+static void mask_ack_pirq(struct irq_data *data)
+{
+ disable_dynirq(data);
+ eoi_pirq(data);
+}
+
+static unsigned int __startup_pirq(unsigned int irq)
+{
+ struct evtchn_bind_pirq bind_pirq;
+ struct irq_info *info = info_for_irq(irq);
+ int evtchn = evtchn_from_irq(irq);
+ int rc;
+
+ BUG_ON(info->type != IRQT_PIRQ);
+
+ if (VALID_EVTCHN(evtchn))
+ goto out;
+
+ bind_pirq.pirq = pirq_from_irq(irq);
+ /* NB. We are happy to share unless we are probing. */
+ bind_pirq.flags = info->u.pirq.flags & PIRQ_SHAREABLE ?
+ BIND_PIRQ__WILL_SHARE : 0;
+ rc = HYPERVISOR_event_channel_op(EVTCHNOP_bind_pirq, &bind_pirq);
+ if (rc != 0) {
+ if (!probing_irq(irq))
+ printk(KERN_INFO "Failed to obtain physical IRQ %d\n",
+ irq);
+ return 0;
+ }
+ evtchn = bind_pirq.port;
+
+ pirq_query_unmask(irq);
+
+ evtchn_to_irq[evtchn] = irq;
+ bind_evtchn_to_cpu(evtchn, 0);
+ info->evtchn = evtchn;
+
+out:
+ unmask_evtchn(evtchn);
+ eoi_pirq(irq_get_irq_data(irq));
+
+ return 0;
+}
+
+static unsigned int startup_pirq(struct irq_data *data)
+{
+ return __startup_pirq(data->irq);
+}
+
+static void shutdown_pirq(struct irq_data *data)
+{
+ struct evtchn_close close;
+ unsigned int irq = data->irq;
+ struct irq_info *info = info_for_irq(irq);
+ int evtchn = evtchn_from_irq(irq);
+
+ BUG_ON(info->type != IRQT_PIRQ);
+
+ if (!VALID_EVTCHN(evtchn))
+ return;
+
+ mask_evtchn(evtchn);
+
+ close.port = evtchn;
+ if (HYPERVISOR_event_channel_op(EVTCHNOP_close, &close) != 0)
+ BUG();
+
+ bind_evtchn_to_cpu(evtchn, 0);
+ evtchn_to_irq[evtchn] = -1;
+ info->evtchn = 0;
+}
+
+static void enable_pirq(struct irq_data *data)
+{
+ startup_pirq(data);
+}
+
+static void disable_pirq(struct irq_data *data)
+{
+ disable_dynirq(data);
+}
+
+static int find_irq_by_gsi(unsigned gsi)
+{
+ struct irq_info *info;
+
+ list_for_each_entry(info, &xen_irq_list_head, list) {
+ if (info->type != IRQT_PIRQ)
+ continue;
+
+ if (info->u.pirq.gsi == gsi)
+ return info->irq;
+ }
+
+ return -1;
+}
+
+int xen_allocate_pirq_gsi(unsigned gsi)
+{
+ return gsi;
+}
+
+/*
+ * Do not make any assumptions regarding the relationship between the
+ * IRQ number returned here and the Xen pirq argument.
+ *
+ * Note: We don't assign an event channel until the irq actually started
+ * up. Return an existing irq if we've already got one for the gsi.
+ *
+ * Shareable implies level triggered, not shareable implies edge
+ * triggered here.
+ */
+int xen_bind_pirq_gsi_to_irq(unsigned gsi,
+ unsigned pirq, int shareable, char *name)
+{
+ int irq = -1;
+ struct physdev_irq irq_op;
+
+ spin_lock(&irq_mapping_update_lock);
+
+ irq = find_irq_by_gsi(gsi);
+ if (irq != -1) {
+ printk(KERN_INFO "xen_map_pirq_gsi: returning irq %d for gsi %u\n",
+ irq, gsi);
+ goto out; /* XXX need refcount? */
+ }
+
+ irq = xen_allocate_irq_gsi(gsi);
+ if (irq < 0)
+ goto out;
+
+ irq_op.irq = irq;
+ irq_op.vector = 0;
+
+ /* Only the privileged domain can do this. For non-priv, the pcifront
+ * driver provides a PCI bus that does the call to do exactly
+ * this in the priv domain. */
+ if (xen_initial_domain() &&
+ HYPERVISOR_physdev_op(PHYSDEVOP_alloc_irq_vector, &irq_op)) {
+ xen_free_irq(irq);
+ irq = -ENOSPC;
+ goto out;
+ }
+
+ xen_irq_info_pirq_init(irq, 0, pirq, gsi, irq_op.vector, DOMID_SELF,
+ shareable ? PIRQ_SHAREABLE : 0);
+
+ pirq_query_unmask(irq);
+ /* We try to use the handler with the appropriate semantic for the
+ * type of interrupt: if the interrupt is an edge triggered
+ * interrupt we use handle_edge_irq.
+ *
+ * On the other hand if the interrupt is level triggered we use
+ * handle_fasteoi_irq like the native code does for this kind of
+ * interrupts.
+ *
+ * Depending on the Xen version, pirq_needs_eoi might return true
+ * not only for level triggered interrupts but for edge triggered
+ * interrupts too. In any case Xen always honors the eoi mechanism,
+ * not injecting any more pirqs of the same kind if the first one
+ * hasn't received an eoi yet. Therefore using the fasteoi handler
+ * is the right choice either way.
+ */
+ if (shareable)
+ irq_set_chip_and_handler_name(irq, &xen_pirq_chip,
+ handle_fasteoi_irq, name);
+ else
+ irq_set_chip_and_handler_name(irq, &xen_pirq_chip,
+ handle_edge_irq, name);
+
+out:
+ spin_unlock(&irq_mapping_update_lock);
+
+ return irq;
+}
+
+#ifdef CONFIG_PCI_MSI
+int xen_allocate_pirq_msi(struct pci_dev *dev, struct msi_desc *msidesc)
+{
+ int rc;
+ struct physdev_get_free_pirq op_get_free_pirq;
+
+ op_get_free_pirq.type = MAP_PIRQ_TYPE_MSI;
+ rc = HYPERVISOR_physdev_op(PHYSDEVOP_get_free_pirq, &op_get_free_pirq);
+
+ WARN_ONCE(rc == -ENOSYS,
+ "hypervisor does not support the PHYSDEVOP_get_free_pirq interface\n");
+
+ return rc ? -1 : op_get_free_pirq.pirq;
+}
+
+int xen_bind_pirq_msi_to_irq(struct pci_dev *dev, struct msi_desc *msidesc,
+ int pirq, int vector, const char *name,
+ domid_t domid)
+{
+ int irq, ret;
+
+ spin_lock(&irq_mapping_update_lock);
+
+ irq = xen_allocate_irq_dynamic();
+ if (irq == -1)
+ goto out;
+
+ irq_set_chip_and_handler_name(irq, &xen_pirq_chip, handle_edge_irq,
+ name);
+
+ xen_irq_info_pirq_init(irq, 0, pirq, 0, vector, domid, 0);
+ ret = irq_set_msi_desc(irq, msidesc);
+ if (ret < 0)
+ goto error_irq;
+out:
+ spin_unlock(&irq_mapping_update_lock);
+ return irq;
+error_irq:
+ spin_unlock(&irq_mapping_update_lock);
+ xen_free_irq(irq);
+ return -1;
+}
+#endif
+
+int xen_destroy_irq(int irq)
+{
+ struct irq_desc *desc;
+ struct physdev_unmap_pirq unmap_irq;
+ struct irq_info *info = info_for_irq(irq);
+ int rc = -ENOENT;
+
+ spin_lock(&irq_mapping_update_lock);
+
+ desc = irq_to_desc(irq);
+ if (!desc)
+ goto out;
+
+ if (xen_initial_domain()) {
+ unmap_irq.pirq = info->u.pirq.pirq;
+ unmap_irq.domid = info->u.pirq.domid;
+ rc = HYPERVISOR_physdev_op(PHYSDEVOP_unmap_pirq, &unmap_irq);
+ /* If another domain quits without making the pci_disable_msix
+ * call, the Xen hypervisor takes care of freeing the PIRQs
+ * (free_domain_pirqs).
+ */
+ if ((rc == -ESRCH && info->u.pirq.domid != DOMID_SELF))
+ printk(KERN_INFO "domain %d does not have %d anymore\n",
+ info->u.pirq.domid, info->u.pirq.pirq);
+ else if (rc) {
+ printk(KERN_WARNING "unmap irq failed %d\n", rc);
+ goto out;
+ }
+ }
+
+ xen_free_irq(irq);
+
+out:
+ spin_unlock(&irq_mapping_update_lock);
+ return rc;
+}
+
+int xen_irq_from_pirq(unsigned pirq)
+{
+ int irq;
+
+ struct irq_info *info;
+
+ spin_lock(&irq_mapping_update_lock);
+
+ list_for_each_entry(info, &xen_irq_list_head, list) {
+ if (info == NULL || info->type != IRQT_PIRQ)
+ continue;
+ irq = info->irq;
+ if (info->u.pirq.pirq == pirq)
+ goto out;
+ }
+ irq = -1;
+out:
+ spin_unlock(&irq_mapping_update_lock);
+
+ return irq;
+}
+
+
+int xen_pirq_from_irq(unsigned irq)
+{
+ return pirq_from_irq(irq);
+}
+EXPORT_SYMBOL_GPL(xen_pirq_from_irq);
+int bind_evtchn_to_irq(unsigned int evtchn)
+{
+ int irq;
+
+ spin_lock(&irq_mapping_update_lock);
+
+ irq = evtchn_to_irq[evtchn];
+
+ if (irq == -1) {
+ irq = xen_allocate_irq_dynamic();
+ if (irq == -1)
+ goto out;
+
+ irq_set_chip_and_handler_name(irq, &xen_dynamic_chip,
+ handle_edge_irq, "event");
+
+ xen_irq_info_evtchn_init(irq, evtchn);
+ }
+
+out:
+ spin_unlock(&irq_mapping_update_lock);
+
+ return irq;
+}
+EXPORT_SYMBOL_GPL(bind_evtchn_to_irq);
+
+static int bind_ipi_to_irq(unsigned int ipi, unsigned int cpu)
+{
+ struct evtchn_bind_ipi bind_ipi;
+ int evtchn, irq;
+
+ spin_lock(&irq_mapping_update_lock);
+
+ irq = per_cpu(ipi_to_irq, cpu)[ipi];
+
+ if (irq == -1) {
+ irq = xen_allocate_irq_dynamic();
+ if (irq < 0)
+ goto out;
+
+ irq_set_chip_and_handler_name(irq, &xen_percpu_chip,
+ handle_percpu_irq, "ipi");
+
+ bind_ipi.vcpu = cpu;
+ if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_ipi,
+ &bind_ipi) != 0)
+ BUG();
+ evtchn = bind_ipi.port;
+
+ xen_irq_info_ipi_init(cpu, irq, evtchn, ipi);
+
+ bind_evtchn_to_cpu(evtchn, cpu);
+ }
+
+ out:
+ spin_unlock(&irq_mapping_update_lock);
+ return irq;
+}
+
+static int bind_interdomain_evtchn_to_irq(unsigned int remote_domain,
+ unsigned int remote_port)
+{
+ struct evtchn_bind_interdomain bind_interdomain;
+ int err;
+
+ bind_interdomain.remote_dom = remote_domain;
+ bind_interdomain.remote_port = remote_port;
+
+ err = HYPERVISOR_event_channel_op(EVTCHNOP_bind_interdomain,
+ &bind_interdomain);
+
+ return err ? : bind_evtchn_to_irq(bind_interdomain.local_port);
+}
+
+
+int bind_virq_to_irq(unsigned int virq, unsigned int cpu)
+{
+ struct evtchn_bind_virq bind_virq;
+ int evtchn, irq;
+
+ spin_lock(&irq_mapping_update_lock);
+
+ irq = per_cpu(virq_to_irq, cpu)[virq];
+
+ if (irq == -1) {
+ irq = xen_allocate_irq_dynamic();
+ if (irq == -1)
+ goto out;
+
+ irq_set_chip_and_handler_name(irq, &xen_percpu_chip,
+ handle_percpu_irq, "virq");
+
+ bind_virq.virq = virq;
+ bind_virq.vcpu = cpu;
+ if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_virq,
+ &bind_virq) != 0)
+ BUG();
+ evtchn = bind_virq.port;
+
+ xen_irq_info_virq_init(cpu, irq, evtchn, virq);
+
+ bind_evtchn_to_cpu(evtchn, cpu);
+ }
+
+out:
+ spin_unlock(&irq_mapping_update_lock);
+
+ return irq;
+}
+
+static void unbind_from_irq(unsigned int irq)
+{
+ struct evtchn_close close;
+ int evtchn = evtchn_from_irq(irq);
+
+ spin_lock(&irq_mapping_update_lock);
+
+ if (VALID_EVTCHN(evtchn)) {
+ close.port = evtchn;
+ if (HYPERVISOR_event_channel_op(EVTCHNOP_close, &close) != 0)
+ BUG();
+
+ switch (type_from_irq(irq)) {
+ case IRQT_VIRQ:
+ per_cpu(virq_to_irq, cpu_from_evtchn(evtchn))
+ [virq_from_irq(irq)] = -1;
+ break;
+ case IRQT_IPI:
+ per_cpu(ipi_to_irq, cpu_from_evtchn(evtchn))
+ [ipi_from_irq(irq)] = -1;
+ break;
+ default:
+ break;
+ }
+
+ /* Closed ports are implicitly re-bound to VCPU0. */
+ bind_evtchn_to_cpu(evtchn, 0);
+
+ evtchn_to_irq[evtchn] = -1;
+ }
+
+ BUG_ON(info_for_irq(irq)->type == IRQT_UNBOUND);
+
+ xen_free_irq(irq);
+
+ spin_unlock(&irq_mapping_update_lock);
+}
+
+int bind_evtchn_to_irqhandler(unsigned int evtchn,
+ irq_handler_t handler,
+ unsigned long irqflags,
+ const char *devname, void *dev_id)
+{
+ int irq, retval;
+
+ irq = bind_evtchn_to_irq(evtchn);
+ if (irq < 0)
+ return irq;
+ retval = request_irq(irq, handler, irqflags, devname, dev_id);
+ if (retval != 0) {
+ unbind_from_irq(irq);
+ return retval;
+ }
+
+ return irq;
+}
+EXPORT_SYMBOL_GPL(bind_evtchn_to_irqhandler);
+
+int bind_interdomain_evtchn_to_irqhandler(unsigned int remote_domain,
+ unsigned int remote_port,
+ irq_handler_t handler,
+ unsigned long irqflags,
+ const char *devname,
+ void *dev_id)
+{
+ int irq, retval;
+
+ irq = bind_interdomain_evtchn_to_irq(remote_domain, remote_port);
+ if (irq < 0)
+ return irq;
+
+ retval = request_irq(irq, handler, irqflags, devname, dev_id);
+ if (retval != 0) {
+ unbind_from_irq(irq);
+ return retval;
+ }
+
+ return irq;
+}
+EXPORT_SYMBOL_GPL(bind_interdomain_evtchn_to_irqhandler);
+
+int bind_virq_to_irqhandler(unsigned int virq, unsigned int cpu,
+ irq_handler_t handler,
+ unsigned long irqflags, const char *devname, void *dev_id)
+{
+ int irq, retval;
+
+ irq = bind_virq_to_irq(virq, cpu);
+ if (irq < 0)
+ return irq;
+ retval = request_irq(irq, handler, irqflags, devname, dev_id);
+ if (retval != 0) {
+ unbind_from_irq(irq);
+ return retval;
+ }
+
+ return irq;
+}
+EXPORT_SYMBOL_GPL(bind_virq_to_irqhandler);
+
+int bind_ipi_to_irqhandler(enum ipi_vector ipi,
+ unsigned int cpu,
+ irq_handler_t handler,
+ unsigned long irqflags,
+ const char *devname,
+ void *dev_id)
+{
+ int irq, retval;
+
+ irq = bind_ipi_to_irq(ipi, cpu);
+ if (irq < 0)
+ return irq;
+
+ irqflags |= IRQF_NO_SUSPEND | IRQF_FORCE_RESUME | IRQF_EARLY_RESUME;
+ retval = request_irq(irq, handler, irqflags, devname, dev_id);
+ if (retval != 0) {
+ unbind_from_irq(irq);
+ return retval;
+ }
+
+ return irq;
+}
+
+void unbind_from_irqhandler(unsigned int irq, void *dev_id)
+{
+ free_irq(irq, dev_id);
+ unbind_from_irq(irq);
+}
+EXPORT_SYMBOL_GPL(unbind_from_irqhandler);
+
+void xen_send_IPI_one(unsigned int cpu, enum ipi_vector vector)
+{
+ int irq = per_cpu(ipi_to_irq, cpu)[vector];
+ BUG_ON(irq < 0);
+ notify_remote_via_irq(irq);
+}
+
+irqreturn_t xen_debug_interrupt(int irq, void *dev_id)
+{
+ struct shared_info *sh = HYPERVISOR_shared_info;
+ int cpu = smp_processor_id();
+ unsigned long *cpu_evtchn = per_cpu(cpu_evtchn_mask, cpu);
+ int i;
+ unsigned long flags;
+ static DEFINE_SPINLOCK(debug_lock);
+ struct vcpu_info *v;
+
+ spin_lock_irqsave(&debug_lock, flags);
+
+ printk("\nvcpu %d\n ", cpu);
+
+ for_each_online_cpu(i) {
+ int pending;
+ v = per_cpu(xen_vcpu, i);
+ pending = (get_irq_regs() && i == cpu)
+ ? xen_irqs_disabled(get_irq_regs())
+ : v->evtchn_upcall_mask;
+ printk("%d: masked=%d pending=%d event_sel %0*lx\n ", i,
+ pending, v->evtchn_upcall_pending,
+ (int)(sizeof(v->evtchn_pending_sel)*2),
+ v->evtchn_pending_sel);
+ }
+ v = per_cpu(xen_vcpu, cpu);
+
+ printk("\npending:\n ");
+ for (i = ARRAY_SIZE(sh->evtchn_pending)-1; i >= 0; i--)
+ printk("%0*lx%s", (int)sizeof(sh->evtchn_pending[0])*2,
+ sh->evtchn_pending[i],
+ i % 8 == 0 ? "\n " : " ");
+ printk("\nglobal mask:\n ");
+ for (i = ARRAY_SIZE(sh->evtchn_mask)-1; i >= 0; i--)
+ printk("%0*lx%s",
+ (int)(sizeof(sh->evtchn_mask[0])*2),
+ sh->evtchn_mask[i],
+ i % 8 == 0 ? "\n " : " ");
+
+ printk("\nglobally unmasked:\n ");
+ for (i = ARRAY_SIZE(sh->evtchn_mask)-1; i >= 0; i--)
+ printk("%0*lx%s", (int)(sizeof(sh->evtchn_mask[0])*2),
+ sh->evtchn_pending[i] & ~sh->evtchn_mask[i],
+ i % 8 == 0 ? "\n " : " ");
+
+ printk("\nlocal cpu%d mask:\n ", cpu);
+ for (i = (NR_EVENT_CHANNELS/BITS_PER_LONG)-1; i >= 0; i--)
+ printk("%0*lx%s", (int)(sizeof(cpu_evtchn[0])*2),
+ cpu_evtchn[i],
+ i % 8 == 0 ? "\n " : " ");
+
+ printk("\nlocally unmasked:\n ");
+ for (i = ARRAY_SIZE(sh->evtchn_mask)-1; i >= 0; i--) {
+ unsigned long pending = sh->evtchn_pending[i]
+ & ~sh->evtchn_mask[i]
+ & cpu_evtchn[i];
+ printk("%0*lx%s", (int)(sizeof(sh->evtchn_mask[0])*2),
+ pending, i % 8 == 0 ? "\n " : " ");
+ }
+
+ printk("\npending list:\n");
+ for (i = 0; i < NR_EVENT_CHANNELS; i++) {
+ if (sync_test_bit(i, sh->evtchn_pending)) {
+ int word_idx = i / BITS_PER_LONG;
+ printk(" %d: event %d -> irq %d%s%s%s\n",
+ cpu_from_evtchn(i), i,
+ evtchn_to_irq[i],
+ sync_test_bit(word_idx, &v->evtchn_pending_sel)
+ ? "" : " l2-clear",
+ !sync_test_bit(i, sh->evtchn_mask)
+ ? "" : " globally-masked",
+ sync_test_bit(i, cpu_evtchn)
+ ? "" : " locally-masked");
+ }
+ }
+
+ spin_unlock_irqrestore(&debug_lock, flags);
+
+ return IRQ_HANDLED;
+}
+
+static DEFINE_PER_CPU(unsigned, xed_nesting_count);
+static DEFINE_PER_CPU(unsigned int, current_word_idx);
+static DEFINE_PER_CPU(unsigned int, current_bit_idx);
+
+/*
+ * Mask out the i least significant bits of w
+ */
+#define MASK_LSBS(w, i) (w & ((~0UL) << i))
+
+/*
+ * Search the CPUs pending events bitmasks. For each one found, map
+ * the event number to an irq, and feed it into do_IRQ() for
+ * handling.
+ *
+ * Xen uses a two-level bitmap to speed searching. The first level is
+ * a bitset of words which contain pending event bits. The second
+ * level is a bitset of pending events themselves.
+ */
+static void __xen_evtchn_do_upcall(void)
+{
+ int start_word_idx, start_bit_idx;
+ int word_idx, bit_idx;
+ int i;
+ int cpu = get_cpu();
+ struct shared_info *s = HYPERVISOR_shared_info;
+ struct vcpu_info *vcpu_info = __this_cpu_read(xen_vcpu);
+ unsigned count;
+
+ do {
+ unsigned long pending_words;
+
+ vcpu_info->evtchn_upcall_pending = 0;
+
+ if (__this_cpu_inc_return(xed_nesting_count) - 1)
+ goto out;
+
+#ifndef CONFIG_X86 /* No need for a barrier -- XCHG is a barrier on x86. */
+ /* Clear master flag /before/ clearing selector flag. */
+ wmb();
+#endif
+ pending_words = xchg(&vcpu_info->evtchn_pending_sel, 0);
+
+ start_word_idx = __this_cpu_read(current_word_idx);
+ start_bit_idx = __this_cpu_read(current_bit_idx);
+
+ word_idx = start_word_idx;
+
+ for (i = 0; pending_words != 0; i++) {
+ unsigned long pending_bits;
+ unsigned long words;
+
+ words = MASK_LSBS(pending_words, word_idx);
+
+ /*
+ * If we masked out all events, wrap to beginning.
+ */
+ if (words == 0) {
+ word_idx = 0;
+ bit_idx = 0;
+ continue;
+ }
+ word_idx = __ffs(words);
+
+ pending_bits = active_evtchns(cpu, s, word_idx);
+ bit_idx = 0; /* usually scan entire word from start */
+ if (word_idx == start_word_idx) {
+ /* We scan the starting word in two parts */
+ if (i == 0)
+ /* 1st time: start in the middle */
+ bit_idx = start_bit_idx;
+ else
+ /* 2nd time: mask bits done already */
+ bit_idx &= (1UL << start_bit_idx) - 1;
+ }
+
+ do {
+ unsigned long bits;
+ int port, irq;
+ struct irq_desc *desc;
+
+ bits = MASK_LSBS(pending_bits, bit_idx);
+
+ /* If we masked out all events, move on. */
+ if (bits == 0)
+ break;
+
+ bit_idx = __ffs(bits);
+
+ /* Process port. */
+ port = (word_idx * BITS_PER_LONG) + bit_idx;
+ irq = evtchn_to_irq[port];
+
+ if (irq != -1) {
+ desc = irq_to_desc(irq);
+ if (desc)
+ generic_handle_irq_desc(irq, desc);
+ }
+
+ bit_idx = (bit_idx + 1) % BITS_PER_LONG;
+
+ /* Next caller starts at last processed + 1 */
+ __this_cpu_write(current_word_idx,
+ bit_idx ? word_idx :
+ (word_idx+1) % BITS_PER_LONG);
+ __this_cpu_write(current_bit_idx, bit_idx);
+ } while (bit_idx != 0);
+
+ /* Scan start_l1i twice; all others once. */
+ if ((word_idx != start_word_idx) || (i != 0))
+ pending_words &= ~(1UL << word_idx);
+
+ word_idx = (word_idx + 1) % BITS_PER_LONG;
+ }
+
+ BUG_ON(!irqs_disabled());
+
+ count = __this_cpu_read(xed_nesting_count);
+ __this_cpu_write(xed_nesting_count, 0);
+ } while (count != 1 || vcpu_info->evtchn_upcall_pending);
+
+out:
+
+ put_cpu();
+}
+
+void xen_evtchn_do_upcall(struct pt_regs *regs)
+{
+ struct pt_regs *old_regs = set_irq_regs(regs);
+
+ exit_idle();
+ irq_enter();
+
+ __xen_evtchn_do_upcall();
+
+ irq_exit();
+ set_irq_regs(old_regs);
+}
+
+void xen_hvm_evtchn_do_upcall(void)
+{
+ __xen_evtchn_do_upcall();
+}
+EXPORT_SYMBOL_GPL(xen_hvm_evtchn_do_upcall);
+
+/* Rebind a new event channel to an existing irq. */
+void rebind_evtchn_irq(int evtchn, int irq)
+{
+ struct irq_info *info = info_for_irq(irq);
+
+ /* Make sure the irq is masked, since the new event channel
+ will also be masked. */
+ disable_irq(irq);
+
+ spin_lock(&irq_mapping_update_lock);
+
+ /* After resume the irq<->evtchn mappings are all cleared out */
+ BUG_ON(evtchn_to_irq[evtchn] != -1);
+ /* Expect irq to have been bound before,
+ so there should be a proper type */
+ BUG_ON(info->type == IRQT_UNBOUND);
+
+ xen_irq_info_evtchn_init(irq, evtchn);
+
+ spin_unlock(&irq_mapping_update_lock);
+
+ /* new event channels are always bound to cpu 0 */
+ irq_set_affinity(irq, cpumask_of(0));
+
+ /* Unmask the event channel. */
+ enable_irq(irq);
+}
+
+/* Rebind an evtchn so that it gets delivered to a specific cpu */
+static int rebind_irq_to_cpu(unsigned irq, unsigned tcpu)
+{
+ struct evtchn_bind_vcpu bind_vcpu;
+ int evtchn = evtchn_from_irq(irq);
+
+ if (!VALID_EVTCHN(evtchn))
+ return -1;
+
+ /*
+ * Events delivered via platform PCI interrupts are always
+ * routed to vcpu 0 and hence cannot be rebound.
+ */
+ if (xen_hvm_domain() && !xen_have_vector_callback)
+ return -1;
+
+ /* Send future instances of this interrupt to other vcpu. */
+ bind_vcpu.port = evtchn;
+ bind_vcpu.vcpu = tcpu;
+
+ /*
+ * If this fails, it usually just indicates that we're dealing with a
+ * virq or IPI channel, which don't actually need to be rebound. Ignore
+ * it, but don't do the xenlinux-level rebind in that case.
+ */
+ if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_vcpu, &bind_vcpu) >= 0)
+ bind_evtchn_to_cpu(evtchn, tcpu);
+
+ return 0;
+}
+
+static int set_affinity_irq(struct irq_data *data, const struct cpumask *dest,
+ bool force)
+{
+ unsigned tcpu = cpumask_first(dest);
+
+ return rebind_irq_to_cpu(data->irq, tcpu);
+}
+
+int resend_irq_on_evtchn(unsigned int irq)
+{
+ int masked, evtchn = evtchn_from_irq(irq);
+ struct shared_info *s = HYPERVISOR_shared_info;
+
+ if (!VALID_EVTCHN(evtchn))
+ return 1;
+
+ masked = sync_test_and_set_bit(evtchn, s->evtchn_mask);
+ sync_set_bit(evtchn, s->evtchn_pending);
+ if (!masked)
+ unmask_evtchn(evtchn);
+
+ return 1;
+}
+
+static void enable_dynirq(struct irq_data *data)
+{
+ int evtchn = evtchn_from_irq(data->irq);
+
+ if (VALID_EVTCHN(evtchn))
+ unmask_evtchn(evtchn);
+}
+
+static void disable_dynirq(struct irq_data *data)
+{
+ int evtchn = evtchn_from_irq(data->irq);
+
+ if (VALID_EVTCHN(evtchn))
+ mask_evtchn(evtchn);
+}
+
+static void ack_dynirq(struct irq_data *data)
+{
+ int evtchn = evtchn_from_irq(data->irq);
+
+ irq_move_irq(data);
+
+ if (VALID_EVTCHN(evtchn))
+ clear_evtchn(evtchn);
+}
+
+static void mask_ack_dynirq(struct irq_data *data)
+{
+ disable_dynirq(data);
+ ack_dynirq(data);
+}
+
+static int retrigger_dynirq(struct irq_data *data)
+{
+ int evtchn = evtchn_from_irq(data->irq);
+ struct shared_info *sh = HYPERVISOR_shared_info;
+ int ret = 0;
+
+ if (VALID_EVTCHN(evtchn)) {
+ int masked;
+
+ masked = sync_test_and_set_bit(evtchn, sh->evtchn_mask);
+ sync_set_bit(evtchn, sh->evtchn_pending);
+ if (!masked)
+ unmask_evtchn(evtchn);
+ ret = 1;
+ }
+
+ return ret;
+}
+
+static void restore_pirqs(void)
+{
+ int pirq, rc, irq, gsi;
+ struct physdev_map_pirq map_irq;
+ struct irq_info *info;
+
+ list_for_each_entry(info, &xen_irq_list_head, list) {
+ if (info->type != IRQT_PIRQ)
+ continue;
+
+ pirq = info->u.pirq.pirq;
+ gsi = info->u.pirq.gsi;
+ irq = info->irq;
+
+ /* save/restore of PT devices doesn't work, so at this point the
+ * only devices present are GSI based emulated devices */
+ if (!gsi)
+ continue;
+
+ map_irq.domid = DOMID_SELF;
+ map_irq.type = MAP_PIRQ_TYPE_GSI;
+ map_irq.index = gsi;
+ map_irq.pirq = pirq;
+
+ rc = HYPERVISOR_physdev_op(PHYSDEVOP_map_pirq, &map_irq);
+ if (rc) {
+ printk(KERN_WARNING "xen map irq failed gsi=%d irq=%d pirq=%d rc=%d\n",
+ gsi, irq, pirq, rc);
+ xen_free_irq(irq);
+ continue;
+ }
+
+ printk(KERN_DEBUG "xen: --> irq=%d, pirq=%d\n", irq, map_irq.pirq);
+
+ __startup_pirq(irq);
+ }
+}
+
+static void restore_cpu_virqs(unsigned int cpu)
+{
+ struct evtchn_bind_virq bind_virq;
+ int virq, irq, evtchn;
+
+ for (virq = 0; virq < NR_VIRQS; virq++) {
+ if ((irq = per_cpu(virq_to_irq, cpu)[virq]) == -1)
+ continue;
+
+ BUG_ON(virq_from_irq(irq) != virq);
+
+ /* Get a new binding from Xen. */
+ bind_virq.virq = virq;
+ bind_virq.vcpu = cpu;
+ if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_virq,
+ &bind_virq) != 0)
+ BUG();
+ evtchn = bind_virq.port;
+
+ /* Record the new mapping. */
+ xen_irq_info_virq_init(cpu, irq, evtchn, virq);
+ bind_evtchn_to_cpu(evtchn, cpu);
+ }
+}
+
+static void restore_cpu_ipis(unsigned int cpu)
+{
+ struct evtchn_bind_ipi bind_ipi;
+ int ipi, irq, evtchn;
+
+ for (ipi = 0; ipi < XEN_NR_IPIS; ipi++) {
+ if ((irq = per_cpu(ipi_to_irq, cpu)[ipi]) == -1)
+ continue;
+
+ BUG_ON(ipi_from_irq(irq) != ipi);
+
+ /* Get a new binding from Xen. */
+ bind_ipi.vcpu = cpu;
+ if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_ipi,
+ &bind_ipi) != 0)
+ BUG();
+ evtchn = bind_ipi.port;
+
+ /* Record the new mapping. */
+ xen_irq_info_ipi_init(cpu, irq, evtchn, ipi);
+ bind_evtchn_to_cpu(evtchn, cpu);
+ }
+}
+
+/* Clear an irq's pending state, in preparation for polling on it */
+void xen_clear_irq_pending(int irq)
+{
+ int evtchn = evtchn_from_irq(irq);
+
+ if (VALID_EVTCHN(evtchn))
+ clear_evtchn(evtchn);
+}
+EXPORT_SYMBOL(xen_clear_irq_pending);
+void xen_set_irq_pending(int irq)
+{
+ int evtchn = evtchn_from_irq(irq);
+
+ if (VALID_EVTCHN(evtchn))
+ set_evtchn(evtchn);
+}
+
+bool xen_test_irq_pending(int irq)
+{
+ int evtchn = evtchn_from_irq(irq);
+ bool ret = false;
+
+ if (VALID_EVTCHN(evtchn))
+ ret = test_evtchn(evtchn);
+
+ return ret;
+}
+
+/* Poll waiting for an irq to become pending with timeout. In the usual case,
+ * the irq will be disabled so it won't deliver an interrupt. */
+void xen_poll_irq_timeout(int irq, u64 timeout)
+{
+ evtchn_port_t evtchn = evtchn_from_irq(irq);
+
+ if (VALID_EVTCHN(evtchn)) {
+ struct sched_poll poll;
+
+ poll.nr_ports = 1;
+ poll.timeout = timeout;
+ set_xen_guest_handle(poll.ports, &evtchn);
+
+ if (HYPERVISOR_sched_op(SCHEDOP_poll, &poll) != 0)
+ BUG();
+ }
+}
+EXPORT_SYMBOL(xen_poll_irq_timeout);
+/* Poll waiting for an irq to become pending. In the usual case, the
+ * irq will be disabled so it won't deliver an interrupt. */
+void xen_poll_irq(int irq)
+{
+ xen_poll_irq_timeout(irq, 0 /* no timeout */);
+}
+
+/* Check whether the IRQ line is shared with other guests. */
+int xen_test_irq_shared(int irq)
+{
+ struct irq_info *info = info_for_irq(irq);
+ struct physdev_irq_status_query irq_status = { .irq = info->u.pirq.pirq };
+
+ if (HYPERVISOR_physdev_op(PHYSDEVOP_irq_status_query, &irq_status))
+ return 0;
+ return !(irq_status.flags & XENIRQSTAT_shared);
+}
+EXPORT_SYMBOL_GPL(xen_test_irq_shared);
+
+void xen_irq_resume(void)
+{
+ unsigned int cpu, evtchn;
+ struct irq_info *info;
+
+ init_evtchn_cpu_bindings();
+
+ /* New event-channel space is not 'live' yet. */
+ for (evtchn = 0; evtchn < NR_EVENT_CHANNELS; evtchn++)
+ mask_evtchn(evtchn);
+
+ /* No IRQ <-> event-channel mappings. */
+ list_for_each_entry(info, &xen_irq_list_head, list)
+ info->evtchn = 0; /* zap event-channel binding */
+
+ for (evtchn = 0; evtchn < NR_EVENT_CHANNELS; evtchn++)
+ evtchn_to_irq[evtchn] = -1;
+
+ for_each_possible_cpu(cpu) {
+ restore_cpu_virqs(cpu);
+ restore_cpu_ipis(cpu);
+ }
+
+ restore_pirqs();
+}
+
+static struct irq_chip xen_dynamic_chip __read_mostly = {
+ .name = "xen-dyn",
+
+ .irq_disable = disable_dynirq,
+ .irq_mask = disable_dynirq,
+ .irq_unmask = enable_dynirq,
+
+ .irq_ack = ack_dynirq,
+ .irq_mask_ack = mask_ack_dynirq,
+
+ .irq_set_affinity = set_affinity_irq,
+ .irq_retrigger = retrigger_dynirq,
+};
+
+static struct irq_chip xen_pirq_chip __read_mostly = {
+ .name = "xen-pirq",
+
+ .irq_startup = startup_pirq,
+ .irq_shutdown = shutdown_pirq,
+ .irq_enable = enable_pirq,
+ .irq_disable = disable_pirq,
+
+ .irq_mask = disable_dynirq,
+ .irq_unmask = enable_dynirq,
+
+ .irq_ack = eoi_pirq,
+ .irq_eoi = eoi_pirq,
+ .irq_mask_ack = mask_ack_pirq,
+
+ .irq_set_affinity = set_affinity_irq,
+
+ .irq_retrigger = retrigger_dynirq,
+};
+
+static struct irq_chip xen_percpu_chip __read_mostly = {
+ .name = "xen-percpu",
+
+ .irq_disable = disable_dynirq,
+ .irq_mask = disable_dynirq,
+ .irq_unmask = enable_dynirq,
+
+ .irq_ack = ack_dynirq,
+};
+
+int xen_set_callback_via(uint64_t via)
+{
+ struct xen_hvm_param a;
+ a.domid = DOMID_SELF;
+ a.index = HVM_PARAM_CALLBACK_IRQ;
+ a.value = via;
+ return HYPERVISOR_hvm_op(HVMOP_set_param, &a);
+}
+EXPORT_SYMBOL_GPL(xen_set_callback_via);
+
+#ifdef CONFIG_XEN_PVHVM
+/* Vector callbacks are better than PCI interrupts to receive event
+ * channel notifications because we can receive vector callbacks on any
+ * vcpu and we don't need PCI support or APIC interactions. */
+void xen_callback_vector(void)
+{
+ int rc;
+ uint64_t callback_via;
+ if (xen_have_vector_callback) {
+ callback_via = HVM_CALLBACK_VECTOR(XEN_HVM_EVTCHN_CALLBACK);
+ rc = xen_set_callback_via(callback_via);
+ if (rc) {
+ printk(KERN_ERR "Request for Xen HVM callback vector"
+ " failed.\n");
+ xen_have_vector_callback = 0;
+ return;
+ }
+ printk(KERN_INFO "Xen HVM callback vector for event delivery is "
+ "enabled\n");
+ /* in the restore case the vector has already been allocated */
+ if (!test_bit(XEN_HVM_EVTCHN_CALLBACK, used_vectors))
+ alloc_intr_gate(XEN_HVM_EVTCHN_CALLBACK, xen_hvm_callback_vector);
+ }
+}
+#else
+void xen_callback_vector(void) {}
+#endif
+
+void __init xen_init_IRQ(void)
+{
+ int i;
+
+ evtchn_to_irq = kcalloc(NR_EVENT_CHANNELS, sizeof(*evtchn_to_irq),
+ GFP_KERNEL);
+ for (i = 0; i < NR_EVENT_CHANNELS; i++)
+ evtchn_to_irq[i] = -1;
+
+ init_evtchn_cpu_bindings();
+
+ /* No event channels are 'live' right now. */
+ for (i = 0; i < NR_EVENT_CHANNELS; i++)
+ mask_evtchn(i);
+
+ if (xen_hvm_domain()) {
+ xen_callback_vector();
+ native_init_IRQ();
+ /* pci_xen_hvm_init must be called after native_init_IRQ so that
+ * __acpi_register_gsi can point at the right function */
+ pci_xen_hvm_init();
+ } else {
+ irq_ctx_init(smp_processor_id());
+ if (xen_initial_domain())
+ xen_setup_pirqs();
+ }
+}
diff --git a/drivers/xen/evtchn.c b/drivers/xen/evtchn.c
new file mode 100644
index 00000000..dbc13e94
--- /dev/null
+++ b/drivers/xen/evtchn.c
@@ -0,0 +1,560 @@
+/******************************************************************************
+ * evtchn.c
+ *
+ * Driver for receiving and demuxing event-channel signals.
+ *
+ * Copyright (c) 2004-2005, K A Fraser
+ * Multi-process extensions Copyright (c) 2004, Steven Smith
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation; or, when distributed
+ * separately from the Linux kernel or incorporated into other
+ * software packages, subject to the following license:
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this source file (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use, copy, modify,
+ * merge, publish, distribute, sublicense, and/or sell copies of the Software,
+ * and to permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/miscdevice.h>
+#include <linux/major.h>
+#include <linux/proc_fs.h>
+#include <linux/stat.h>
+#include <linux/poll.h>
+#include <linux/irq.h>
+#include <linux/init.h>
+#include <linux/mutex.h>
+#include <linux/cpu.h>
+
+#include <xen/xen.h>
+#include <xen/events.h>
+#include <xen/evtchn.h>
+#include <asm/xen/hypervisor.h>
+
+struct per_user_data {
+ struct mutex bind_mutex; /* serialize bind/unbind operations */
+
+ /* Notification ring, accessed via /dev/xen/evtchn. */
+#define EVTCHN_RING_SIZE (PAGE_SIZE / sizeof(evtchn_port_t))
+#define EVTCHN_RING_MASK(_i) ((_i)&(EVTCHN_RING_SIZE-1))
+ evtchn_port_t *ring;
+ unsigned int ring_cons, ring_prod, ring_overflow;
+ struct mutex ring_cons_mutex; /* protect against concurrent readers */
+
+ /* Processes wait on this queue when ring is empty. */
+ wait_queue_head_t evtchn_wait;
+ struct fasync_struct *evtchn_async_queue;
+ const char *name;
+};
+
+/*
+ * Who's bound to each port? This is logically an array of struct
+ * per_user_data *, but we encode the current enabled-state in bit 0.
+ */
+static unsigned long *port_user;
+static DEFINE_SPINLOCK(port_user_lock); /* protects port_user[] and ring_prod */
+
+static inline struct per_user_data *get_port_user(unsigned port)
+{
+ return (struct per_user_data *)(port_user[port] & ~1);
+}
+
+static inline void set_port_user(unsigned port, struct per_user_data *u)
+{
+ port_user[port] = (unsigned long)u;
+}
+
+static inline bool get_port_enabled(unsigned port)
+{
+ return port_user[port] & 1;
+}
+
+static inline void set_port_enabled(unsigned port, bool enabled)
+{
+ if (enabled)
+ port_user[port] |= 1;
+ else
+ port_user[port] &= ~1;
+}
+
+static irqreturn_t evtchn_interrupt(int irq, void *data)
+{
+ unsigned int port = (unsigned long)data;
+ struct per_user_data *u;
+
+ spin_lock(&port_user_lock);
+
+ u = get_port_user(port);
+
+ WARN(!get_port_enabled(port),
+ "Interrupt for port %d, but apparently not enabled; per-user %p\n",
+ port, u);
+
+ disable_irq_nosync(irq);
+ set_port_enabled(port, false);
+
+ if ((u->ring_prod - u->ring_cons) < EVTCHN_RING_SIZE) {
+ u->ring[EVTCHN_RING_MASK(u->ring_prod)] = port;
+ wmb(); /* Ensure ring contents visible */
+ if (u->ring_cons == u->ring_prod++) {
+ wake_up_interruptible(&u->evtchn_wait);
+ kill_fasync(&u->evtchn_async_queue,
+ SIGIO, POLL_IN);
+ }
+ } else
+ u->ring_overflow = 1;
+
+ spin_unlock(&port_user_lock);
+
+ return IRQ_HANDLED;
+}
+
+static ssize_t evtchn_read(struct file *file, char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ int rc;
+ unsigned int c, p, bytes1 = 0, bytes2 = 0;
+ struct per_user_data *u = file->private_data;
+
+ /* Whole number of ports. */
+ count &= ~(sizeof(evtchn_port_t)-1);
+
+ if (count == 0)
+ return 0;
+
+ if (count > PAGE_SIZE)
+ count = PAGE_SIZE;
+
+ for (;;) {
+ mutex_lock(&u->ring_cons_mutex);
+
+ rc = -EFBIG;
+ if (u->ring_overflow)
+ goto unlock_out;
+
+ c = u->ring_cons;
+ p = u->ring_prod;
+ if (c != p)
+ break;
+
+ mutex_unlock(&u->ring_cons_mutex);
+
+ if (file->f_flags & O_NONBLOCK)
+ return -EAGAIN;
+
+ rc = wait_event_interruptible(u->evtchn_wait,
+ u->ring_cons != u->ring_prod);
+ if (rc)
+ return rc;
+ }
+
+ /* Byte lengths of two chunks. Chunk split (if any) is at ring wrap. */
+ if (((c ^ p) & EVTCHN_RING_SIZE) != 0) {
+ bytes1 = (EVTCHN_RING_SIZE - EVTCHN_RING_MASK(c)) *
+ sizeof(evtchn_port_t);
+ bytes2 = EVTCHN_RING_MASK(p) * sizeof(evtchn_port_t);
+ } else {
+ bytes1 = (p - c) * sizeof(evtchn_port_t);
+ bytes2 = 0;
+ }
+
+ /* Truncate chunks according to caller's maximum byte count. */
+ if (bytes1 > count) {
+ bytes1 = count;
+ bytes2 = 0;
+ } else if ((bytes1 + bytes2) > count) {
+ bytes2 = count - bytes1;
+ }
+
+ rc = -EFAULT;
+ rmb(); /* Ensure that we see the port before we copy it. */
+ if (copy_to_user(buf, &u->ring[EVTCHN_RING_MASK(c)], bytes1) ||
+ ((bytes2 != 0) &&
+ copy_to_user(&buf[bytes1], &u->ring[0], bytes2)))
+ goto unlock_out;
+
+ u->ring_cons += (bytes1 + bytes2) / sizeof(evtchn_port_t);
+ rc = bytes1 + bytes2;
+
+ unlock_out:
+ mutex_unlock(&u->ring_cons_mutex);
+ return rc;
+}
+
+static ssize_t evtchn_write(struct file *file, const char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ int rc, i;
+ evtchn_port_t *kbuf = (evtchn_port_t *)__get_free_page(GFP_KERNEL);
+ struct per_user_data *u = file->private_data;
+
+ if (kbuf == NULL)
+ return -ENOMEM;
+
+ /* Whole number of ports. */
+ count &= ~(sizeof(evtchn_port_t)-1);
+
+ rc = 0;
+ if (count == 0)
+ goto out;
+
+ if (count > PAGE_SIZE)
+ count = PAGE_SIZE;
+
+ rc = -EFAULT;
+ if (copy_from_user(kbuf, buf, count) != 0)
+ goto out;
+
+ spin_lock_irq(&port_user_lock);
+
+ for (i = 0; i < (count/sizeof(evtchn_port_t)); i++) {
+ unsigned port = kbuf[i];
+
+ if (port < NR_EVENT_CHANNELS &&
+ get_port_user(port) == u &&
+ !get_port_enabled(port)) {
+ set_port_enabled(port, true);
+ enable_irq(irq_from_evtchn(port));
+ }
+ }
+
+ spin_unlock_irq(&port_user_lock);
+
+ rc = count;
+
+ out:
+ free_page((unsigned long)kbuf);
+ return rc;
+}
+
+static int evtchn_bind_to_user(struct per_user_data *u, int port)
+{
+ int rc = 0;
+
+ /*
+ * Ports are never reused, so every caller should pass in a
+ * unique port.
+ *
+ * (Locking not necessary because we haven't registered the
+ * interrupt handler yet, and our caller has already
+ * serialized bind operations.)
+ */
+ BUG_ON(get_port_user(port) != NULL);
+ set_port_user(port, u);
+ set_port_enabled(port, true); /* start enabled */
+
+ rc = bind_evtchn_to_irqhandler(port, evtchn_interrupt, IRQF_DISABLED,
+ u->name, (void *)(unsigned long)port);
+ if (rc >= 0)
+ rc = 0;
+
+ return rc;
+}
+
+static void evtchn_unbind_from_user(struct per_user_data *u, int port)
+{
+ int irq = irq_from_evtchn(port);
+
+ unbind_from_irqhandler(irq, (void *)(unsigned long)port);
+
+ set_port_user(port, NULL);
+}
+
+static long evtchn_ioctl(struct file *file,
+ unsigned int cmd, unsigned long arg)
+{
+ int rc;
+ struct per_user_data *u = file->private_data;
+ void __user *uarg = (void __user *) arg;
+
+ /* Prevent bind from racing with unbind */
+ mutex_lock(&u->bind_mutex);
+
+ switch (cmd) {
+ case IOCTL_EVTCHN_BIND_VIRQ: {
+ struct ioctl_evtchn_bind_virq bind;
+ struct evtchn_bind_virq bind_virq;
+
+ rc = -EFAULT;
+ if (copy_from_user(&bind, uarg, sizeof(bind)))
+ break;
+
+ bind_virq.virq = bind.virq;
+ bind_virq.vcpu = 0;
+ rc = HYPERVISOR_event_channel_op(EVTCHNOP_bind_virq,
+ &bind_virq);
+ if (rc != 0)
+ break;
+
+ rc = evtchn_bind_to_user(u, bind_virq.port);
+ if (rc == 0)
+ rc = bind_virq.port;
+ break;
+ }
+
+ case IOCTL_EVTCHN_BIND_INTERDOMAIN: {
+ struct ioctl_evtchn_bind_interdomain bind;
+ struct evtchn_bind_interdomain bind_interdomain;
+
+ rc = -EFAULT;
+ if (copy_from_user(&bind, uarg, sizeof(bind)))
+ break;
+
+ bind_interdomain.remote_dom = bind.remote_domain;
+ bind_interdomain.remote_port = bind.remote_port;
+ rc = HYPERVISOR_event_channel_op(EVTCHNOP_bind_interdomain,
+ &bind_interdomain);
+ if (rc != 0)
+ break;
+
+ rc = evtchn_bind_to_user(u, bind_interdomain.local_port);
+ if (rc == 0)
+ rc = bind_interdomain.local_port;
+ break;
+ }
+
+ case IOCTL_EVTCHN_BIND_UNBOUND_PORT: {
+ struct ioctl_evtchn_bind_unbound_port bind;
+ struct evtchn_alloc_unbound alloc_unbound;
+
+ rc = -EFAULT;
+ if (copy_from_user(&bind, uarg, sizeof(bind)))
+ break;
+
+ alloc_unbound.dom = DOMID_SELF;
+ alloc_unbound.remote_dom = bind.remote_domain;
+ rc = HYPERVISOR_event_channel_op(EVTCHNOP_alloc_unbound,
+ &alloc_unbound);
+ if (rc != 0)
+ break;
+
+ rc = evtchn_bind_to_user(u, alloc_unbound.port);
+ if (rc == 0)
+ rc = alloc_unbound.port;
+ break;
+ }
+
+ case IOCTL_EVTCHN_UNBIND: {
+ struct ioctl_evtchn_unbind unbind;
+
+ rc = -EFAULT;
+ if (copy_from_user(&unbind, uarg, sizeof(unbind)))
+ break;
+
+ rc = -EINVAL;
+ if (unbind.port >= NR_EVENT_CHANNELS)
+ break;
+
+ spin_lock_irq(&port_user_lock);
+
+ rc = -ENOTCONN;
+ if (get_port_user(unbind.port) != u) {
+ spin_unlock_irq(&port_user_lock);
+ break;
+ }
+
+ disable_irq(irq_from_evtchn(unbind.port));
+
+ spin_unlock_irq(&port_user_lock);
+
+ evtchn_unbind_from_user(u, unbind.port);
+
+ rc = 0;
+ break;
+ }
+
+ case IOCTL_EVTCHN_NOTIFY: {
+ struct ioctl_evtchn_notify notify;
+
+ rc = -EFAULT;
+ if (copy_from_user(&notify, uarg, sizeof(notify)))
+ break;
+
+ if (notify.port >= NR_EVENT_CHANNELS) {
+ rc = -EINVAL;
+ } else if (get_port_user(notify.port) != u) {
+ rc = -ENOTCONN;
+ } else {
+ notify_remote_via_evtchn(notify.port);
+ rc = 0;
+ }
+ break;
+ }
+
+ case IOCTL_EVTCHN_RESET: {
+ /* Initialise the ring to empty. Clear errors. */
+ mutex_lock(&u->ring_cons_mutex);
+ spin_lock_irq(&port_user_lock);
+ u->ring_cons = u->ring_prod = u->ring_overflow = 0;
+ spin_unlock_irq(&port_user_lock);
+ mutex_unlock(&u->ring_cons_mutex);
+ rc = 0;
+ break;
+ }
+
+ default:
+ rc = -ENOSYS;
+ break;
+ }
+ mutex_unlock(&u->bind_mutex);
+
+ return rc;
+}
+
+static unsigned int evtchn_poll(struct file *file, poll_table *wait)
+{
+ unsigned int mask = POLLOUT | POLLWRNORM;
+ struct per_user_data *u = file->private_data;
+
+ poll_wait(file, &u->evtchn_wait, wait);
+ if (u->ring_cons != u->ring_prod)
+ mask |= POLLIN | POLLRDNORM;
+ if (u->ring_overflow)
+ mask = POLLERR;
+ return mask;
+}
+
+static int evtchn_fasync(int fd, struct file *filp, int on)
+{
+ struct per_user_data *u = filp->private_data;
+ return fasync_helper(fd, filp, on, &u->evtchn_async_queue);
+}
+
+static int evtchn_open(struct inode *inode, struct file *filp)
+{
+ struct per_user_data *u;
+
+ u = kzalloc(sizeof(*u), GFP_KERNEL);
+ if (u == NULL)
+ return -ENOMEM;
+
+ u->name = kasprintf(GFP_KERNEL, "evtchn:%s", current->comm);
+ if (u->name == NULL) {
+ kfree(u);
+ return -ENOMEM;
+ }
+
+ init_waitqueue_head(&u->evtchn_wait);
+
+ u->ring = (evtchn_port_t *)__get_free_page(GFP_KERNEL);
+ if (u->ring == NULL) {
+ kfree(u->name);
+ kfree(u);
+ return -ENOMEM;
+ }
+
+ mutex_init(&u->bind_mutex);
+ mutex_init(&u->ring_cons_mutex);
+
+ filp->private_data = u;
+
+ return nonseekable_open(inode, filp);
+}
+
+static int evtchn_release(struct inode *inode, struct file *filp)
+{
+ int i;
+ struct per_user_data *u = filp->private_data;
+
+ spin_lock_irq(&port_user_lock);
+
+ free_page((unsigned long)u->ring);
+
+ for (i = 0; i < NR_EVENT_CHANNELS; i++) {
+ if (get_port_user(i) != u)
+ continue;
+
+ disable_irq(irq_from_evtchn(i));
+ }
+
+ spin_unlock_irq(&port_user_lock);
+
+ for (i = 0; i < NR_EVENT_CHANNELS; i++) {
+ if (get_port_user(i) != u)
+ continue;
+
+ evtchn_unbind_from_user(get_port_user(i), i);
+ }
+
+ kfree(u->name);
+ kfree(u);
+
+ return 0;
+}
+
+static const struct file_operations evtchn_fops = {
+ .owner = THIS_MODULE,
+ .read = evtchn_read,
+ .write = evtchn_write,
+ .unlocked_ioctl = evtchn_ioctl,
+ .poll = evtchn_poll,
+ .fasync = evtchn_fasync,
+ .open = evtchn_open,
+ .release = evtchn_release,
+ .llseek = no_llseek,
+};
+
+static struct miscdevice evtchn_miscdev = {
+ .minor = MISC_DYNAMIC_MINOR,
+ .name = "xen/evtchn",
+ .fops = &evtchn_fops,
+};
+static int __init evtchn_init(void)
+{
+ int err;
+
+ if (!xen_domain())
+ return -ENODEV;
+
+ port_user = kcalloc(NR_EVENT_CHANNELS, sizeof(*port_user), GFP_KERNEL);
+ if (port_user == NULL)
+ return -ENOMEM;
+
+ spin_lock_init(&port_user_lock);
+
+ /* Create '/dev/misc/evtchn'. */
+ err = misc_register(&evtchn_miscdev);
+ if (err != 0) {
+ printk(KERN_ALERT "Could not register /dev/misc/evtchn\n");
+ return err;
+ }
+
+ printk(KERN_INFO "Event-channel device installed.\n");
+
+ return 0;
+}
+
+static void __exit evtchn_cleanup(void)
+{
+ kfree(port_user);
+ port_user = NULL;
+
+ misc_deregister(&evtchn_miscdev);
+}
+
+module_init(evtchn_init);
+module_exit(evtchn_cleanup);
+
+MODULE_LICENSE("GPL");
diff --git a/drivers/xen/features.c b/drivers/xen/features.c
new file mode 100644
index 00000000..99eda169
--- /dev/null
+++ b/drivers/xen/features.c
@@ -0,0 +1,33 @@
+/******************************************************************************
+ * features.c
+ *
+ * Xen feature flags.
+ *
+ * Copyright (c) 2006, Ian Campbell, XenSource Inc.
+ */
+#include <linux/types.h>
+#include <linux/cache.h>
+#include <linux/module.h>
+
+#include <asm/xen/hypercall.h>
+
+#include <xen/interface/xen.h>
+#include <xen/interface/version.h>
+#include <xen/features.h>
+
+u8 xen_features[XENFEAT_NR_SUBMAPS * 32] __read_mostly;
+EXPORT_SYMBOL_GPL(xen_features);
+
+void xen_setup_features(void)
+{
+ struct xen_feature_info fi;
+ int i, j;
+
+ for (i = 0; i < XENFEAT_NR_SUBMAPS; i++) {
+ fi.submap_idx = i;
+ if (HYPERVISOR_xen_version(XENVER_get_features, &fi) < 0)
+ break;
+ for (j = 0; j < 32; j++)
+ xen_features[i * 32 + j] = !!(fi.submap & 1<<j);
+ }
+}
diff --git a/drivers/xen/gntalloc.c b/drivers/xen/gntalloc.c
new file mode 100644
index 00000000..e1c4c6e5
--- /dev/null
+++ b/drivers/xen/gntalloc.c
@@ -0,0 +1,555 @@
+/******************************************************************************
+ * gntalloc.c
+ *
+ * Device for creating grant references (in user-space) that may be shared
+ * with other domains.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+/*
+ * This driver exists to allow userspace programs in Linux to allocate kernel
+ * memory that will later be shared with another domain. Without this device,
+ * Linux userspace programs cannot create grant references.
+ *
+ * How this stuff works:
+ * X -> granting a page to Y
+ * Y -> mapping the grant from X
+ *
+ * 1. X uses the gntalloc device to allocate a page of kernel memory, P.
+ * 2. X creates an entry in the grant table that says domid(Y) can access P.
+ * This is done without a hypercall unless the grant table needs expansion.
+ * 3. X gives the grant reference identifier, GREF, to Y.
+ * 4. Y maps the page, either directly into kernel memory for use in a backend
+ * driver, or via a the gntdev device to map into the address space of an
+ * application running in Y. This is the first point at which Xen does any
+ * tracking of the page.
+ * 5. A program in X mmap()s a segment of the gntalloc device that corresponds
+ * to the shared page, and can now communicate with Y over the shared page.
+ *
+ *
+ * NOTE TO USERSPACE LIBRARIES:
+ * The grant allocation and mmap()ing are, naturally, two separate operations.
+ * You set up the sharing by calling the create ioctl() and then the mmap().
+ * Teardown requires munmap() and either close() or ioctl().
+ *
+ * WARNING: Since Xen does not allow a guest to forcibly end the use of a grant
+ * reference, this device can be used to consume kernel memory by leaving grant
+ * references mapped by another domain when an application exits. Therefore,
+ * there is a global limit on the number of pages that can be allocated. When
+ * all references to the page are unmapped, it will be freed during the next
+ * grant operation.
+ */
+
+#include <linux/atomic.h>
+#include <linux/module.h>
+#include <linux/miscdevice.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/fs.h>
+#include <linux/device.h>
+#include <linux/mm.h>
+#include <linux/uaccess.h>
+#include <linux/types.h>
+#include <linux/list.h>
+#include <linux/highmem.h>
+
+#include <xen/xen.h>
+#include <xen/page.h>
+#include <xen/grant_table.h>
+#include <xen/gntalloc.h>
+#include <xen/events.h>
+
+static int limit = 1024;
+module_param(limit, int, 0644);
+MODULE_PARM_DESC(limit, "Maximum number of grants that may be allocated by "
+ "the gntalloc device");
+
+static LIST_HEAD(gref_list);
+static DEFINE_SPINLOCK(gref_lock);
+static int gref_size;
+
+struct notify_info {
+ uint16_t pgoff:12; /* Bits 0-11: Offset of the byte to clear */
+ uint16_t flags:2; /* Bits 12-13: Unmap notification flags */
+ int event; /* Port (event channel) to notify */
+};
+
+/* Metadata on a grant reference. */
+struct gntalloc_gref {
+ struct list_head next_gref; /* list entry gref_list */
+ struct list_head next_file; /* list entry file->list, if open */
+ struct page *page; /* The shared page */
+ uint64_t file_index; /* File offset for mmap() */
+ unsigned int users; /* Use count - when zero, waiting on Xen */
+ grant_ref_t gref_id; /* The grant reference number */
+ struct notify_info notify; /* Unmap notification */
+};
+
+struct gntalloc_file_private_data {
+ struct list_head list;
+ uint64_t index;
+};
+
+static void __del_gref(struct gntalloc_gref *gref);
+
+static void do_cleanup(void)
+{
+ struct gntalloc_gref *gref, *n;
+ list_for_each_entry_safe(gref, n, &gref_list, next_gref) {
+ if (!gref->users)
+ __del_gref(gref);
+ }
+}
+
+static int add_grefs(struct ioctl_gntalloc_alloc_gref *op,
+ uint32_t *gref_ids, struct gntalloc_file_private_data *priv)
+{
+ int i, rc, readonly;
+ LIST_HEAD(queue_gref);
+ LIST_HEAD(queue_file);
+ struct gntalloc_gref *gref;
+
+ readonly = !(op->flags & GNTALLOC_FLAG_WRITABLE);
+ rc = -ENOMEM;
+ for (i = 0; i < op->count; i++) {
+ gref = kzalloc(sizeof(*gref), GFP_KERNEL);
+ if (!gref)
+ goto undo;
+ list_add_tail(&gref->next_gref, &queue_gref);
+ list_add_tail(&gref->next_file, &queue_file);
+ gref->users = 1;
+ gref->file_index = op->index + i * PAGE_SIZE;
+ gref->page = alloc_page(GFP_KERNEL|__GFP_ZERO);
+ if (!gref->page)
+ goto undo;
+
+ /* Grant foreign access to the page. */
+ gref->gref_id = gnttab_grant_foreign_access(op->domid,
+ pfn_to_mfn(page_to_pfn(gref->page)), readonly);
+ if ((int)gref->gref_id < 0) {
+ rc = gref->gref_id;
+ goto undo;
+ }
+ gref_ids[i] = gref->gref_id;
+ }
+
+ /* Add to gref lists. */
+ spin_lock(&gref_lock);
+ list_splice_tail(&queue_gref, &gref_list);
+ list_splice_tail(&queue_file, &priv->list);
+ spin_unlock(&gref_lock);
+
+ return 0;
+
+undo:
+ spin_lock(&gref_lock);
+ gref_size -= (op->count - i);
+
+ list_for_each_entry(gref, &queue_file, next_file) {
+ /* __del_gref does not remove from queue_file */
+ __del_gref(gref);
+ }
+
+ /* It's possible for the target domain to map the just-allocated grant
+ * references by blindly guessing their IDs; if this is done, then
+ * __del_gref will leave them in the queue_gref list. They need to be
+ * added to the global list so that we can free them when they are no
+ * longer referenced.
+ */
+ if (unlikely(!list_empty(&queue_gref)))
+ list_splice_tail(&queue_gref, &gref_list);
+ spin_unlock(&gref_lock);
+ return rc;
+}
+
+static void __del_gref(struct gntalloc_gref *gref)
+{
+ if (gref->notify.flags & UNMAP_NOTIFY_CLEAR_BYTE) {
+ uint8_t *tmp = kmap(gref->page);
+ tmp[gref->notify.pgoff] = 0;
+ kunmap(gref->page);
+ }
+ if (gref->notify.flags & UNMAP_NOTIFY_SEND_EVENT)
+ notify_remote_via_evtchn(gref->notify.event);
+
+ gref->notify.flags = 0;
+
+ if (gref->gref_id > 0) {
+ if (gnttab_query_foreign_access(gref->gref_id))
+ return;
+
+ if (!gnttab_end_foreign_access_ref(gref->gref_id, 0))
+ return;
+ }
+
+ gref_size--;
+ list_del(&gref->next_gref);
+
+ if (gref->page)
+ __free_page(gref->page);
+
+ kfree(gref);
+}
+
+/* finds contiguous grant references in a file, returns the first */
+static struct gntalloc_gref *find_grefs(struct gntalloc_file_private_data *priv,
+ uint64_t index, uint32_t count)
+{
+ struct gntalloc_gref *rv = NULL, *gref;
+ list_for_each_entry(gref, &priv->list, next_file) {
+ if (gref->file_index == index && !rv)
+ rv = gref;
+ if (rv) {
+ if (gref->file_index != index)
+ return NULL;
+ index += PAGE_SIZE;
+ count--;
+ if (count == 0)
+ return rv;
+ }
+ }
+ return NULL;
+}
+
+/*
+ * -------------------------------------
+ * File operations.
+ * -------------------------------------
+ */
+static int gntalloc_open(struct inode *inode, struct file *filp)
+{
+ struct gntalloc_file_private_data *priv;
+
+ priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ goto out_nomem;
+ INIT_LIST_HEAD(&priv->list);
+
+ filp->private_data = priv;
+
+ pr_debug("%s: priv %p\n", __func__, priv);
+
+ return 0;
+
+out_nomem:
+ return -ENOMEM;
+}
+
+static int gntalloc_release(struct inode *inode, struct file *filp)
+{
+ struct gntalloc_file_private_data *priv = filp->private_data;
+ struct gntalloc_gref *gref;
+
+ pr_debug("%s: priv %p\n", __func__, priv);
+
+ spin_lock(&gref_lock);
+ while (!list_empty(&priv->list)) {
+ gref = list_entry(priv->list.next,
+ struct gntalloc_gref, next_file);
+ list_del(&gref->next_file);
+ gref->users--;
+ if (gref->users == 0)
+ __del_gref(gref);
+ }
+ kfree(priv);
+ spin_unlock(&gref_lock);
+
+ return 0;
+}
+
+static long gntalloc_ioctl_alloc(struct gntalloc_file_private_data *priv,
+ struct ioctl_gntalloc_alloc_gref __user *arg)
+{
+ int rc = 0;
+ struct ioctl_gntalloc_alloc_gref op;
+ uint32_t *gref_ids;
+
+ pr_debug("%s: priv %p\n", __func__, priv);
+
+ if (copy_from_user(&op, arg, sizeof(op))) {
+ rc = -EFAULT;
+ goto out;
+ }
+
+ gref_ids = kcalloc(op.count, sizeof(gref_ids[0]), GFP_TEMPORARY);
+ if (!gref_ids) {
+ rc = -ENOMEM;
+ goto out;
+ }
+
+ spin_lock(&gref_lock);
+ /* Clean up pages that were at zero (local) users but were still mapped
+ * by remote domains. Since those pages count towards the limit that we
+ * are about to enforce, removing them here is a good idea.
+ */
+ do_cleanup();
+ if (gref_size + op.count > limit) {
+ spin_unlock(&gref_lock);
+ rc = -ENOSPC;
+ goto out_free;
+ }
+ gref_size += op.count;
+ op.index = priv->index;
+ priv->index += op.count * PAGE_SIZE;
+ spin_unlock(&gref_lock);
+
+ rc = add_grefs(&op, gref_ids, priv);
+ if (rc < 0)
+ goto out_free;
+
+ /* Once we finish add_grefs, it is unsafe to touch the new reference,
+ * since it is possible for a concurrent ioctl to remove it (by guessing
+ * its index). If the userspace application doesn't provide valid memory
+ * to write the IDs to, then it will need to close the file in order to
+ * release - which it will do by segfaulting when it tries to access the
+ * IDs to close them.
+ */
+ if (copy_to_user(arg, &op, sizeof(op))) {
+ rc = -EFAULT;
+ goto out_free;
+ }
+ if (copy_to_user(arg->gref_ids, gref_ids,
+ sizeof(gref_ids[0]) * op.count)) {
+ rc = -EFAULT;
+ goto out_free;
+ }
+
+out_free:
+ kfree(gref_ids);
+out:
+ return rc;
+}
+
+static long gntalloc_ioctl_dealloc(struct gntalloc_file_private_data *priv,
+ void __user *arg)
+{
+ int i, rc = 0;
+ struct ioctl_gntalloc_dealloc_gref op;
+ struct gntalloc_gref *gref, *n;
+
+ pr_debug("%s: priv %p\n", __func__, priv);
+
+ if (copy_from_user(&op, arg, sizeof(op))) {
+ rc = -EFAULT;
+ goto dealloc_grant_out;
+ }
+
+ spin_lock(&gref_lock);
+ gref = find_grefs(priv, op.index, op.count);
+ if (gref) {
+ /* Remove from the file list only, and decrease reference count.
+ * The later call to do_cleanup() will remove from gref_list and
+ * free the memory if the pages aren't mapped anywhere.
+ */
+ for (i = 0; i < op.count; i++) {
+ n = list_entry(gref->next_file.next,
+ struct gntalloc_gref, next_file);
+ list_del(&gref->next_file);
+ gref->users--;
+ gref = n;
+ }
+ } else {
+ rc = -EINVAL;
+ }
+
+ do_cleanup();
+
+ spin_unlock(&gref_lock);
+dealloc_grant_out:
+ return rc;
+}
+
+static long gntalloc_ioctl_unmap_notify(struct gntalloc_file_private_data *priv,
+ void __user *arg)
+{
+ struct ioctl_gntalloc_unmap_notify op;
+ struct gntalloc_gref *gref;
+ uint64_t index;
+ int pgoff;
+ int rc;
+
+ if (copy_from_user(&op, arg, sizeof(op)))
+ return -EFAULT;
+
+ index = op.index & ~(PAGE_SIZE - 1);
+ pgoff = op.index & (PAGE_SIZE - 1);
+
+ spin_lock(&gref_lock);
+
+ gref = find_grefs(priv, index, 1);
+ if (!gref) {
+ rc = -ENOENT;
+ goto unlock_out;
+ }
+
+ if (op.action & ~(UNMAP_NOTIFY_CLEAR_BYTE|UNMAP_NOTIFY_SEND_EVENT)) {
+ rc = -EINVAL;
+ goto unlock_out;
+ }
+
+ gref->notify.flags = op.action;
+ gref->notify.pgoff = pgoff;
+ gref->notify.event = op.event_channel_port;
+ rc = 0;
+ unlock_out:
+ spin_unlock(&gref_lock);
+ return rc;
+}
+
+static long gntalloc_ioctl(struct file *filp, unsigned int cmd,
+ unsigned long arg)
+{
+ struct gntalloc_file_private_data *priv = filp->private_data;
+
+ switch (cmd) {
+ case IOCTL_GNTALLOC_ALLOC_GREF:
+ return gntalloc_ioctl_alloc(priv, (void __user *)arg);
+
+ case IOCTL_GNTALLOC_DEALLOC_GREF:
+ return gntalloc_ioctl_dealloc(priv, (void __user *)arg);
+
+ case IOCTL_GNTALLOC_SET_UNMAP_NOTIFY:
+ return gntalloc_ioctl_unmap_notify(priv, (void __user *)arg);
+
+ default:
+ return -ENOIOCTLCMD;
+ }
+
+ return 0;
+}
+
+static void gntalloc_vma_open(struct vm_area_struct *vma)
+{
+ struct gntalloc_gref *gref = vma->vm_private_data;
+ if (!gref)
+ return;
+
+ spin_lock(&gref_lock);
+ gref->users++;
+ spin_unlock(&gref_lock);
+}
+
+static void gntalloc_vma_close(struct vm_area_struct *vma)
+{
+ struct gntalloc_gref *gref = vma->vm_private_data;
+ if (!gref)
+ return;
+
+ spin_lock(&gref_lock);
+ gref->users--;
+ if (gref->users == 0)
+ __del_gref(gref);
+ spin_unlock(&gref_lock);
+}
+
+static struct vm_operations_struct gntalloc_vmops = {
+ .open = gntalloc_vma_open,
+ .close = gntalloc_vma_close,
+};
+
+static int gntalloc_mmap(struct file *filp, struct vm_area_struct *vma)
+{
+ struct gntalloc_file_private_data *priv = filp->private_data;
+ struct gntalloc_gref *gref;
+ int count = (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
+ int rv, i;
+
+ pr_debug("%s: priv %p, page %lu+%d\n", __func__,
+ priv, vma->vm_pgoff, count);
+
+ if (!(vma->vm_flags & VM_SHARED)) {
+ printk(KERN_ERR "%s: Mapping must be shared.\n", __func__);
+ return -EINVAL;
+ }
+
+ spin_lock(&gref_lock);
+ gref = find_grefs(priv, vma->vm_pgoff << PAGE_SHIFT, count);
+ if (gref == NULL) {
+ rv = -ENOENT;
+ pr_debug("%s: Could not find grant reference",
+ __func__);
+ goto out_unlock;
+ }
+
+ vma->vm_private_data = gref;
+
+ vma->vm_flags |= VM_RESERVED;
+
+ vma->vm_ops = &gntalloc_vmops;
+
+ for (i = 0; i < count; i++) {
+ gref->users++;
+ rv = vm_insert_page(vma, vma->vm_start + i * PAGE_SIZE,
+ gref->page);
+ if (rv)
+ goto out_unlock;
+
+ gref = list_entry(gref->next_file.next,
+ struct gntalloc_gref, next_file);
+ }
+ rv = 0;
+
+out_unlock:
+ spin_unlock(&gref_lock);
+ return rv;
+}
+
+static const struct file_operations gntalloc_fops = {
+ .owner = THIS_MODULE,
+ .open = gntalloc_open,
+ .release = gntalloc_release,
+ .unlocked_ioctl = gntalloc_ioctl,
+ .mmap = gntalloc_mmap
+};
+
+/*
+ * -------------------------------------
+ * Module creation/destruction.
+ * -------------------------------------
+ */
+static struct miscdevice gntalloc_miscdev = {
+ .minor = MISC_DYNAMIC_MINOR,
+ .name = "xen/gntalloc",
+ .fops = &gntalloc_fops,
+};
+
+static int __init gntalloc_init(void)
+{
+ int err;
+
+ if (!xen_domain())
+ return -ENODEV;
+
+ err = misc_register(&gntalloc_miscdev);
+ if (err != 0) {
+ printk(KERN_ERR "Could not register misc gntalloc device\n");
+ return err;
+ }
+
+ pr_debug("Created grant allocation device at %d,%d\n",
+ MISC_MAJOR, gntalloc_miscdev.minor);
+
+ return 0;
+}
+
+static void __exit gntalloc_exit(void)
+{
+ misc_deregister(&gntalloc_miscdev);
+}
+
+module_init(gntalloc_init);
+module_exit(gntalloc_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Carter Weatherly <carter.weatherly@jhuapl.edu>, "
+ "Daniel De Graaf <dgdegra@tycho.nsa.gov>");
+MODULE_DESCRIPTION("User-space grant reference allocator driver");
diff --git a/drivers/xen/gntdev.c b/drivers/xen/gntdev.c
new file mode 100644
index 00000000..b4e830eb
--- /dev/null
+++ b/drivers/xen/gntdev.c
@@ -0,0 +1,765 @@
+/******************************************************************************
+ * gntdev.c
+ *
+ * Device for accessing (in user-space) pages that have been granted by other
+ * domains.
+ *
+ * Copyright (c) 2006-2007, D G Murray.
+ * (c) 2009 Gerd Hoffmann <kraxel@redhat.com>
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#undef DEBUG
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/miscdevice.h>
+#include <linux/fs.h>
+#include <linux/mm.h>
+#include <linux/mman.h>
+#include <linux/mmu_notifier.h>
+#include <linux/types.h>
+#include <linux/uaccess.h>
+#include <linux/sched.h>
+#include <linux/spinlock.h>
+#include <linux/slab.h>
+#include <linux/highmem.h>
+
+#include <xen/xen.h>
+#include <xen/grant_table.h>
+#include <xen/balloon.h>
+#include <xen/gntdev.h>
+#include <xen/events.h>
+#include <asm/xen/hypervisor.h>
+#include <asm/xen/hypercall.h>
+#include <asm/xen/page.h>
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Derek G. Murray <Derek.Murray@cl.cam.ac.uk>, "
+ "Gerd Hoffmann <kraxel@redhat.com>");
+MODULE_DESCRIPTION("User-space granted page access driver");
+
+static int limit = 1024*1024;
+module_param(limit, int, 0644);
+MODULE_PARM_DESC(limit, "Maximum number of grants that may be mapped by "
+ "the gntdev device");
+
+static atomic_t pages_mapped = ATOMIC_INIT(0);
+
+static int use_ptemod;
+
+struct gntdev_priv {
+ struct list_head maps;
+ /* lock protects maps from concurrent changes */
+ spinlock_t lock;
+ struct mm_struct *mm;
+ struct mmu_notifier mn;
+};
+
+struct unmap_notify {
+ int flags;
+ /* Address relative to the start of the grant_map */
+ int addr;
+ int event;
+};
+
+struct grant_map {
+ struct list_head next;
+ struct vm_area_struct *vma;
+ int index;
+ int count;
+ int flags;
+ atomic_t users;
+ struct unmap_notify notify;
+ struct ioctl_gntdev_grant_ref *grants;
+ struct gnttab_map_grant_ref *map_ops;
+ struct gnttab_unmap_grant_ref *unmap_ops;
+ struct page **pages;
+};
+
+static int unmap_grant_pages(struct grant_map *map, int offset, int pages);
+
+/* ------------------------------------------------------------------ */
+
+static void gntdev_print_maps(struct gntdev_priv *priv,
+ char *text, int text_index)
+{
+#ifdef DEBUG
+ struct grant_map *map;
+
+ pr_debug("%s: maps list (priv %p)\n", __func__, priv);
+ list_for_each_entry(map, &priv->maps, next)
+ pr_debug(" index %2d, count %2d %s\n",
+ map->index, map->count,
+ map->index == text_index && text ? text : "");
+#endif
+}
+
+static struct grant_map *gntdev_alloc_map(struct gntdev_priv *priv, int count)
+{
+ struct grant_map *add;
+ int i;
+
+ add = kzalloc(sizeof(struct grant_map), GFP_KERNEL);
+ if (NULL == add)
+ return NULL;
+
+ add->grants = kzalloc(sizeof(add->grants[0]) * count, GFP_KERNEL);
+ add->map_ops = kzalloc(sizeof(add->map_ops[0]) * count, GFP_KERNEL);
+ add->unmap_ops = kzalloc(sizeof(add->unmap_ops[0]) * count, GFP_KERNEL);
+ add->pages = kzalloc(sizeof(add->pages[0]) * count, GFP_KERNEL);
+ if (NULL == add->grants ||
+ NULL == add->map_ops ||
+ NULL == add->unmap_ops ||
+ NULL == add->pages)
+ goto err;
+
+ if (alloc_xenballooned_pages(count, add->pages))
+ goto err;
+
+ for (i = 0; i < count; i++) {
+ add->map_ops[i].handle = -1;
+ add->unmap_ops[i].handle = -1;
+ }
+
+ add->index = 0;
+ add->count = count;
+ atomic_set(&add->users, 1);
+
+ return add;
+
+err:
+ kfree(add->pages);
+ kfree(add->grants);
+ kfree(add->map_ops);
+ kfree(add->unmap_ops);
+ kfree(add);
+ return NULL;
+}
+
+static void gntdev_add_map(struct gntdev_priv *priv, struct grant_map *add)
+{
+ struct grant_map *map;
+
+ list_for_each_entry(map, &priv->maps, next) {
+ if (add->index + add->count < map->index) {
+ list_add_tail(&add->next, &map->next);
+ goto done;
+ }
+ add->index = map->index + map->count;
+ }
+ list_add_tail(&add->next, &priv->maps);
+
+done:
+ gntdev_print_maps(priv, "[new]", add->index);
+}
+
+static struct grant_map *gntdev_find_map_index(struct gntdev_priv *priv,
+ int index, int count)
+{
+ struct grant_map *map;
+
+ list_for_each_entry(map, &priv->maps, next) {
+ if (map->index != index)
+ continue;
+ if (count && map->count != count)
+ continue;
+ return map;
+ }
+ return NULL;
+}
+
+static void gntdev_put_map(struct grant_map *map)
+{
+ if (!map)
+ return;
+
+ if (!atomic_dec_and_test(&map->users))
+ return;
+
+ atomic_sub(map->count, &pages_mapped);
+
+ if (map->notify.flags & UNMAP_NOTIFY_SEND_EVENT) {
+ notify_remote_via_evtchn(map->notify.event);
+ }
+
+ if (map->pages) {
+ if (!use_ptemod)
+ unmap_grant_pages(map, 0, map->count);
+
+ free_xenballooned_pages(map->count, map->pages);
+ }
+ kfree(map->pages);
+ kfree(map->grants);
+ kfree(map->map_ops);
+ kfree(map->unmap_ops);
+ kfree(map);
+}
+
+/* ------------------------------------------------------------------ */
+
+static int find_grant_ptes(pte_t *pte, pgtable_t token,
+ unsigned long addr, void *data)
+{
+ struct grant_map *map = data;
+ unsigned int pgnr = (addr - map->vma->vm_start) >> PAGE_SHIFT;
+ int flags = map->flags | GNTMAP_application_map | GNTMAP_contains_pte;
+ u64 pte_maddr;
+
+ BUG_ON(pgnr >= map->count);
+ pte_maddr = arbitrary_virt_to_machine(pte).maddr;
+
+ gnttab_set_map_op(&map->map_ops[pgnr], pte_maddr, flags,
+ map->grants[pgnr].ref,
+ map->grants[pgnr].domid);
+ gnttab_set_unmap_op(&map->unmap_ops[pgnr], pte_maddr, flags,
+ -1 /* handle */);
+ return 0;
+}
+
+static int map_grant_pages(struct grant_map *map)
+{
+ int i, err = 0;
+
+ if (!use_ptemod) {
+ /* Note: it could already be mapped */
+ if (map->map_ops[0].handle != -1)
+ return 0;
+ for (i = 0; i < map->count; i++) {
+ unsigned long addr = (unsigned long)
+ pfn_to_kaddr(page_to_pfn(map->pages[i]));
+ gnttab_set_map_op(&map->map_ops[i], addr, map->flags,
+ map->grants[i].ref,
+ map->grants[i].domid);
+ gnttab_set_unmap_op(&map->unmap_ops[i], addr,
+ map->flags, -1 /* handle */);
+ }
+ }
+
+ pr_debug("map %d+%d\n", map->index, map->count);
+ err = gnttab_map_refs(map->map_ops, map->pages, map->count);
+ if (err)
+ return err;
+
+ for (i = 0; i < map->count; i++) {
+ if (map->map_ops[i].status)
+ err = -EINVAL;
+ else {
+ BUG_ON(map->map_ops[i].handle == -1);
+ map->unmap_ops[i].handle = map->map_ops[i].handle;
+ pr_debug("map handle=%d\n", map->map_ops[i].handle);
+ }
+ }
+ return err;
+}
+
+static int __unmap_grant_pages(struct grant_map *map, int offset, int pages)
+{
+ int i, err = 0;
+
+ if (map->notify.flags & UNMAP_NOTIFY_CLEAR_BYTE) {
+ int pgno = (map->notify.addr >> PAGE_SHIFT);
+ if (pgno >= offset && pgno < offset + pages && use_ptemod) {
+ void __user *tmp = (void __user *)
+ map->vma->vm_start + map->notify.addr;
+ err = copy_to_user(tmp, &err, 1);
+ if (err)
+ return -EFAULT;
+ map->notify.flags &= ~UNMAP_NOTIFY_CLEAR_BYTE;
+ } else if (pgno >= offset && pgno < offset + pages) {
+ uint8_t *tmp = kmap(map->pages[pgno]);
+ tmp[map->notify.addr & (PAGE_SIZE-1)] = 0;
+ kunmap(map->pages[pgno]);
+ map->notify.flags &= ~UNMAP_NOTIFY_CLEAR_BYTE;
+ }
+ }
+
+ err = gnttab_unmap_refs(map->unmap_ops + offset, map->pages + offset, pages);
+ if (err)
+ return err;
+
+ for (i = 0; i < pages; i++) {
+ if (map->unmap_ops[offset+i].status)
+ err = -EINVAL;
+ pr_debug("unmap handle=%d st=%d\n",
+ map->unmap_ops[offset+i].handle,
+ map->unmap_ops[offset+i].status);
+ map->unmap_ops[offset+i].handle = -1;
+ }
+ return err;
+}
+
+static int unmap_grant_pages(struct grant_map *map, int offset, int pages)
+{
+ int range, err = 0;
+
+ pr_debug("unmap %d+%d [%d+%d]\n", map->index, map->count, offset, pages);
+
+ /* It is possible the requested range will have a "hole" where we
+ * already unmapped some of the grants. Only unmap valid ranges.
+ */
+ while (pages && !err) {
+ while (pages && map->unmap_ops[offset].handle == -1) {
+ offset++;
+ pages--;
+ }
+ range = 0;
+ while (range < pages) {
+ if (map->unmap_ops[offset+range].handle == -1) {
+ range--;
+ break;
+ }
+ range++;
+ }
+ err = __unmap_grant_pages(map, offset, range);
+ offset += range;
+ pages -= range;
+ }
+
+ return err;
+}
+
+/* ------------------------------------------------------------------ */
+
+static void gntdev_vma_open(struct vm_area_struct *vma)
+{
+ struct grant_map *map = vma->vm_private_data;
+
+ pr_debug("gntdev_vma_open %p\n", vma);
+ atomic_inc(&map->users);
+}
+
+static void gntdev_vma_close(struct vm_area_struct *vma)
+{
+ struct grant_map *map = vma->vm_private_data;
+
+ pr_debug("gntdev_vma_close %p\n", vma);
+ map->vma = NULL;
+ vma->vm_private_data = NULL;
+ gntdev_put_map(map);
+}
+
+static struct vm_operations_struct gntdev_vmops = {
+ .open = gntdev_vma_open,
+ .close = gntdev_vma_close,
+};
+
+/* ------------------------------------------------------------------ */
+
+static void mn_invl_range_start(struct mmu_notifier *mn,
+ struct mm_struct *mm,
+ unsigned long start, unsigned long end)
+{
+ struct gntdev_priv *priv = container_of(mn, struct gntdev_priv, mn);
+ struct grant_map *map;
+ unsigned long mstart, mend;
+ int err;
+
+ spin_lock(&priv->lock);
+ list_for_each_entry(map, &priv->maps, next) {
+ if (!map->vma)
+ continue;
+ if (map->vma->vm_start >= end)
+ continue;
+ if (map->vma->vm_end <= start)
+ continue;
+ mstart = max(start, map->vma->vm_start);
+ mend = min(end, map->vma->vm_end);
+ pr_debug("map %d+%d (%lx %lx), range %lx %lx, mrange %lx %lx\n",
+ map->index, map->count,
+ map->vma->vm_start, map->vma->vm_end,
+ start, end, mstart, mend);
+ err = unmap_grant_pages(map,
+ (mstart - map->vma->vm_start) >> PAGE_SHIFT,
+ (mend - mstart) >> PAGE_SHIFT);
+ WARN_ON(err);
+ }
+ spin_unlock(&priv->lock);
+}
+
+static void mn_invl_page(struct mmu_notifier *mn,
+ struct mm_struct *mm,
+ unsigned long address)
+{
+ mn_invl_range_start(mn, mm, address, address + PAGE_SIZE);
+}
+
+static void mn_release(struct mmu_notifier *mn,
+ struct mm_struct *mm)
+{
+ struct gntdev_priv *priv = container_of(mn, struct gntdev_priv, mn);
+ struct grant_map *map;
+ int err;
+
+ spin_lock(&priv->lock);
+ list_for_each_entry(map, &priv->maps, next) {
+ if (!map->vma)
+ continue;
+ pr_debug("map %d+%d (%lx %lx)\n",
+ map->index, map->count,
+ map->vma->vm_start, map->vma->vm_end);
+ err = unmap_grant_pages(map, /* offset */ 0, map->count);
+ WARN_ON(err);
+ }
+ spin_unlock(&priv->lock);
+}
+
+struct mmu_notifier_ops gntdev_mmu_ops = {
+ .release = mn_release,
+ .invalidate_page = mn_invl_page,
+ .invalidate_range_start = mn_invl_range_start,
+};
+
+/* ------------------------------------------------------------------ */
+
+static int gntdev_open(struct inode *inode, struct file *flip)
+{
+ struct gntdev_priv *priv;
+ int ret = 0;
+
+ priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ INIT_LIST_HEAD(&priv->maps);
+ spin_lock_init(&priv->lock);
+
+ if (use_ptemod) {
+ priv->mm = get_task_mm(current);
+ if (!priv->mm) {
+ kfree(priv);
+ return -ENOMEM;
+ }
+ priv->mn.ops = &gntdev_mmu_ops;
+ ret = mmu_notifier_register(&priv->mn, priv->mm);
+ mmput(priv->mm);
+ }
+
+ if (ret) {
+ kfree(priv);
+ return ret;
+ }
+
+ flip->private_data = priv;
+ pr_debug("priv %p\n", priv);
+
+ return 0;
+}
+
+static int gntdev_release(struct inode *inode, struct file *flip)
+{
+ struct gntdev_priv *priv = flip->private_data;
+ struct grant_map *map;
+
+ pr_debug("priv %p\n", priv);
+
+ spin_lock(&priv->lock);
+ while (!list_empty(&priv->maps)) {
+ map = list_entry(priv->maps.next, struct grant_map, next);
+ list_del(&map->next);
+ gntdev_put_map(map);
+ }
+ spin_unlock(&priv->lock);
+
+ if (use_ptemod)
+ mmu_notifier_unregister(&priv->mn, priv->mm);
+ kfree(priv);
+ return 0;
+}
+
+static long gntdev_ioctl_map_grant_ref(struct gntdev_priv *priv,
+ struct ioctl_gntdev_map_grant_ref __user *u)
+{
+ struct ioctl_gntdev_map_grant_ref op;
+ struct grant_map *map;
+ int err;
+
+ if (copy_from_user(&op, u, sizeof(op)) != 0)
+ return -EFAULT;
+ pr_debug("priv %p, add %d\n", priv, op.count);
+ if (unlikely(op.count <= 0))
+ return -EINVAL;
+
+ err = -ENOMEM;
+ map = gntdev_alloc_map(priv, op.count);
+ if (!map)
+ return err;
+
+ if (unlikely(atomic_add_return(op.count, &pages_mapped) > limit)) {
+ pr_debug("can't map: over limit\n");
+ gntdev_put_map(map);
+ return err;
+ }
+
+ if (copy_from_user(map->grants, &u->refs,
+ sizeof(map->grants[0]) * op.count) != 0) {
+ gntdev_put_map(map);
+ return err;
+ }
+
+ spin_lock(&priv->lock);
+ gntdev_add_map(priv, map);
+ op.index = map->index << PAGE_SHIFT;
+ spin_unlock(&priv->lock);
+
+ if (copy_to_user(u, &op, sizeof(op)) != 0)
+ return -EFAULT;
+
+ return 0;
+}
+
+static long gntdev_ioctl_unmap_grant_ref(struct gntdev_priv *priv,
+ struct ioctl_gntdev_unmap_grant_ref __user *u)
+{
+ struct ioctl_gntdev_unmap_grant_ref op;
+ struct grant_map *map;
+ int err = -ENOENT;
+
+ if (copy_from_user(&op, u, sizeof(op)) != 0)
+ return -EFAULT;
+ pr_debug("priv %p, del %d+%d\n", priv, (int)op.index, (int)op.count);
+
+ spin_lock(&priv->lock);
+ map = gntdev_find_map_index(priv, op.index >> PAGE_SHIFT, op.count);
+ if (map) {
+ list_del(&map->next);
+ gntdev_put_map(map);
+ err = 0;
+ }
+ spin_unlock(&priv->lock);
+ return err;
+}
+
+static long gntdev_ioctl_get_offset_for_vaddr(struct gntdev_priv *priv,
+ struct ioctl_gntdev_get_offset_for_vaddr __user *u)
+{
+ struct ioctl_gntdev_get_offset_for_vaddr op;
+ struct vm_area_struct *vma;
+ struct grant_map *map;
+
+ if (copy_from_user(&op, u, sizeof(op)) != 0)
+ return -EFAULT;
+ pr_debug("priv %p, offset for vaddr %lx\n", priv, (unsigned long)op.vaddr);
+
+ vma = find_vma(current->mm, op.vaddr);
+ if (!vma || vma->vm_ops != &gntdev_vmops)
+ return -EINVAL;
+
+ map = vma->vm_private_data;
+ if (!map)
+ return -EINVAL;
+
+ op.offset = map->index << PAGE_SHIFT;
+ op.count = map->count;
+
+ if (copy_to_user(u, &op, sizeof(op)) != 0)
+ return -EFAULT;
+ return 0;
+}
+
+static long gntdev_ioctl_notify(struct gntdev_priv *priv, void __user *u)
+{
+ struct ioctl_gntdev_unmap_notify op;
+ struct grant_map *map;
+ int rc;
+
+ if (copy_from_user(&op, u, sizeof(op)))
+ return -EFAULT;
+
+ if (op.action & ~(UNMAP_NOTIFY_CLEAR_BYTE|UNMAP_NOTIFY_SEND_EVENT))
+ return -EINVAL;
+
+ spin_lock(&priv->lock);
+
+ list_for_each_entry(map, &priv->maps, next) {
+ uint64_t begin = map->index << PAGE_SHIFT;
+ uint64_t end = (map->index + map->count) << PAGE_SHIFT;
+ if (op.index >= begin && op.index < end)
+ goto found;
+ }
+ rc = -ENOENT;
+ goto unlock_out;
+
+ found:
+ if ((op.action & UNMAP_NOTIFY_CLEAR_BYTE) &&
+ (map->flags & GNTMAP_readonly)) {
+ rc = -EINVAL;
+ goto unlock_out;
+ }
+
+ map->notify.flags = op.action;
+ map->notify.addr = op.index - (map->index << PAGE_SHIFT);
+ map->notify.event = op.event_channel_port;
+ rc = 0;
+ unlock_out:
+ spin_unlock(&priv->lock);
+ return rc;
+}
+
+static long gntdev_ioctl(struct file *flip,
+ unsigned int cmd, unsigned long arg)
+{
+ struct gntdev_priv *priv = flip->private_data;
+ void __user *ptr = (void __user *)arg;
+
+ switch (cmd) {
+ case IOCTL_GNTDEV_MAP_GRANT_REF:
+ return gntdev_ioctl_map_grant_ref(priv, ptr);
+
+ case IOCTL_GNTDEV_UNMAP_GRANT_REF:
+ return gntdev_ioctl_unmap_grant_ref(priv, ptr);
+
+ case IOCTL_GNTDEV_GET_OFFSET_FOR_VADDR:
+ return gntdev_ioctl_get_offset_for_vaddr(priv, ptr);
+
+ case IOCTL_GNTDEV_SET_UNMAP_NOTIFY:
+ return gntdev_ioctl_notify(priv, ptr);
+
+ default:
+ pr_debug("priv %p, unknown cmd %x\n", priv, cmd);
+ return -ENOIOCTLCMD;
+ }
+
+ return 0;
+}
+
+static int gntdev_mmap(struct file *flip, struct vm_area_struct *vma)
+{
+ struct gntdev_priv *priv = flip->private_data;
+ int index = vma->vm_pgoff;
+ int count = (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
+ struct grant_map *map;
+ int i, err = -EINVAL;
+
+ if ((vma->vm_flags & VM_WRITE) && !(vma->vm_flags & VM_SHARED))
+ return -EINVAL;
+
+ pr_debug("map %d+%d at %lx (pgoff %lx)\n",
+ index, count, vma->vm_start, vma->vm_pgoff);
+
+ spin_lock(&priv->lock);
+ map = gntdev_find_map_index(priv, index, count);
+ if (!map)
+ goto unlock_out;
+ if (use_ptemod && map->vma)
+ goto unlock_out;
+ if (use_ptemod && priv->mm != vma->vm_mm) {
+ printk(KERN_WARNING "Huh? Other mm?\n");
+ goto unlock_out;
+ }
+
+ atomic_inc(&map->users);
+
+ vma->vm_ops = &gntdev_vmops;
+
+ vma->vm_flags |= VM_RESERVED|VM_DONTEXPAND;
+
+ if (use_ptemod)
+ vma->vm_flags |= VM_DONTCOPY;
+
+ vma->vm_private_data = map;
+
+ if (use_ptemod)
+ map->vma = vma;
+
+ if (map->flags) {
+ if ((vma->vm_flags & VM_WRITE) &&
+ (map->flags & GNTMAP_readonly))
+ goto out_unlock_put;
+ } else {
+ map->flags = GNTMAP_host_map;
+ if (!(vma->vm_flags & VM_WRITE))
+ map->flags |= GNTMAP_readonly;
+ }
+
+ spin_unlock(&priv->lock);
+
+ if (use_ptemod) {
+ err = apply_to_page_range(vma->vm_mm, vma->vm_start,
+ vma->vm_end - vma->vm_start,
+ find_grant_ptes, map);
+ if (err) {
+ printk(KERN_WARNING "find_grant_ptes() failure.\n");
+ goto out_put_map;
+ }
+ }
+
+ err = map_grant_pages(map);
+ if (err)
+ goto out_put_map;
+
+ if (!use_ptemod) {
+ for (i = 0; i < count; i++) {
+ err = vm_insert_page(vma, vma->vm_start + i*PAGE_SIZE,
+ map->pages[i]);
+ if (err)
+ goto out_put_map;
+ }
+ }
+
+ return 0;
+
+unlock_out:
+ spin_unlock(&priv->lock);
+ return err;
+
+out_unlock_put:
+ spin_unlock(&priv->lock);
+out_put_map:
+ if (use_ptemod)
+ map->vma = NULL;
+ gntdev_put_map(map);
+ return err;
+}
+
+static const struct file_operations gntdev_fops = {
+ .owner = THIS_MODULE,
+ .open = gntdev_open,
+ .release = gntdev_release,
+ .mmap = gntdev_mmap,
+ .unlocked_ioctl = gntdev_ioctl
+};
+
+static struct miscdevice gntdev_miscdev = {
+ .minor = MISC_DYNAMIC_MINOR,
+ .name = "xen/gntdev",
+ .fops = &gntdev_fops,
+};
+
+/* ------------------------------------------------------------------ */
+
+static int __init gntdev_init(void)
+{
+ int err;
+
+ if (!xen_domain())
+ return -ENODEV;
+
+ use_ptemod = xen_pv_domain();
+
+ err = misc_register(&gntdev_miscdev);
+ if (err != 0) {
+ printk(KERN_ERR "Could not register gntdev device\n");
+ return err;
+ }
+ return 0;
+}
+
+static void __exit gntdev_exit(void)
+{
+ misc_deregister(&gntdev_miscdev);
+}
+
+module_init(gntdev_init);
+module_exit(gntdev_exit);
+
+/* ------------------------------------------------------------------ */
diff --git a/drivers/xen/grant-table.c b/drivers/xen/grant-table.c
new file mode 100644
index 00000000..fd725cde
--- /dev/null
+++ b/drivers/xen/grant-table.c
@@ -0,0 +1,690 @@
+/******************************************************************************
+ * grant_table.c
+ *
+ * Granting foreign access to our memory reservation.
+ *
+ * Copyright (c) 2005-2006, Christopher Clark
+ * Copyright (c) 2004-2005, K A Fraser
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation; or, when distributed
+ * separately from the Linux kernel or incorporated into other
+ * software packages, subject to the following license:
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this source file (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use, copy, modify,
+ * merge, publish, distribute, sublicense, and/or sell copies of the Software,
+ * and to permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <linux/vmalloc.h>
+#include <linux/uaccess.h>
+#include <linux/io.h>
+
+#include <xen/xen.h>
+#include <xen/interface/xen.h>
+#include <xen/page.h>
+#include <xen/grant_table.h>
+#include <xen/interface/memory.h>
+#include <asm/xen/hypercall.h>
+
+#include <asm/pgtable.h>
+#include <asm/sync_bitops.h>
+
+
+/* External tools reserve first few grant table entries. */
+#define NR_RESERVED_ENTRIES 8
+#define GNTTAB_LIST_END 0xffffffff
+#define GREFS_PER_GRANT_FRAME (PAGE_SIZE / sizeof(struct grant_entry))
+
+static grant_ref_t **gnttab_list;
+static unsigned int nr_grant_frames;
+static unsigned int boot_max_nr_grant_frames;
+static int gnttab_free_count;
+static grant_ref_t gnttab_free_head;
+static DEFINE_SPINLOCK(gnttab_list_lock);
+unsigned long xen_hvm_resume_frames;
+EXPORT_SYMBOL_GPL(xen_hvm_resume_frames);
+
+static struct grant_entry *shared;
+
+static struct gnttab_free_callback *gnttab_free_callback_list;
+
+static int gnttab_expand(unsigned int req_entries);
+
+#define RPP (PAGE_SIZE / sizeof(grant_ref_t))
+
+static inline grant_ref_t *__gnttab_entry(grant_ref_t entry)
+{
+ return &gnttab_list[(entry) / RPP][(entry) % RPP];
+}
+/* This can be used as an l-value */
+#define gnttab_entry(entry) (*__gnttab_entry(entry))
+
+static int get_free_entries(unsigned count)
+{
+ unsigned long flags;
+ int ref, rc;
+ grant_ref_t head;
+
+ spin_lock_irqsave(&gnttab_list_lock, flags);
+
+ if ((gnttab_free_count < count) &&
+ ((rc = gnttab_expand(count - gnttab_free_count)) < 0)) {
+ spin_unlock_irqrestore(&gnttab_list_lock, flags);
+ return rc;
+ }
+
+ ref = head = gnttab_free_head;
+ gnttab_free_count -= count;
+ while (count-- > 1)
+ head = gnttab_entry(head);
+ gnttab_free_head = gnttab_entry(head);
+ gnttab_entry(head) = GNTTAB_LIST_END;
+
+ spin_unlock_irqrestore(&gnttab_list_lock, flags);
+
+ return ref;
+}
+
+static void do_free_callbacks(void)
+{
+ struct gnttab_free_callback *callback, *next;
+
+ callback = gnttab_free_callback_list;
+ gnttab_free_callback_list = NULL;
+
+ while (callback != NULL) {
+ next = callback->next;
+ if (gnttab_free_count >= callback->count) {
+ callback->next = NULL;
+ callback->fn(callback->arg);
+ } else {
+ callback->next = gnttab_free_callback_list;
+ gnttab_free_callback_list = callback;
+ }
+ callback = next;
+ }
+}
+
+static inline void check_free_callbacks(void)
+{
+ if (unlikely(gnttab_free_callback_list))
+ do_free_callbacks();
+}
+
+static void put_free_entry(grant_ref_t ref)
+{
+ unsigned long flags;
+ spin_lock_irqsave(&gnttab_list_lock, flags);
+ gnttab_entry(ref) = gnttab_free_head;
+ gnttab_free_head = ref;
+ gnttab_free_count++;
+ check_free_callbacks();
+ spin_unlock_irqrestore(&gnttab_list_lock, flags);
+}
+
+static void update_grant_entry(grant_ref_t ref, domid_t domid,
+ unsigned long frame, unsigned flags)
+{
+ /*
+ * Introducing a valid entry into the grant table:
+ * 1. Write ent->domid.
+ * 2. Write ent->frame:
+ * GTF_permit_access: Frame to which access is permitted.
+ * GTF_accept_transfer: Pseudo-phys frame slot being filled by new
+ * frame, or zero if none.
+ * 3. Write memory barrier (WMB).
+ * 4. Write ent->flags, inc. valid type.
+ */
+ shared[ref].frame = frame;
+ shared[ref].domid = domid;
+ wmb();
+ shared[ref].flags = flags;
+}
+
+/*
+ * Public grant-issuing interface functions
+ */
+void gnttab_grant_foreign_access_ref(grant_ref_t ref, domid_t domid,
+ unsigned long frame, int readonly)
+{
+ update_grant_entry(ref, domid, frame,
+ GTF_permit_access | (readonly ? GTF_readonly : 0));
+}
+EXPORT_SYMBOL_GPL(gnttab_grant_foreign_access_ref);
+
+int gnttab_grant_foreign_access(domid_t domid, unsigned long frame,
+ int readonly)
+{
+ int ref;
+
+ ref = get_free_entries(1);
+ if (unlikely(ref < 0))
+ return -ENOSPC;
+
+ gnttab_grant_foreign_access_ref(ref, domid, frame, readonly);
+
+ return ref;
+}
+EXPORT_SYMBOL_GPL(gnttab_grant_foreign_access);
+
+int gnttab_query_foreign_access(grant_ref_t ref)
+{
+ u16 nflags;
+
+ nflags = shared[ref].flags;
+
+ return (nflags & (GTF_reading|GTF_writing));
+}
+EXPORT_SYMBOL_GPL(gnttab_query_foreign_access);
+
+int gnttab_end_foreign_access_ref(grant_ref_t ref, int readonly)
+{
+ u16 flags, nflags;
+
+ nflags = shared[ref].flags;
+ do {
+ flags = nflags;
+ if (flags & (GTF_reading|GTF_writing)) {
+ printk(KERN_ALERT "WARNING: g.e. still in use!\n");
+ return 0;
+ }
+ } while ((nflags = sync_cmpxchg(&shared[ref].flags, flags, 0)) != flags);
+
+ return 1;
+}
+EXPORT_SYMBOL_GPL(gnttab_end_foreign_access_ref);
+
+void gnttab_end_foreign_access(grant_ref_t ref, int readonly,
+ unsigned long page)
+{
+ if (gnttab_end_foreign_access_ref(ref, readonly)) {
+ put_free_entry(ref);
+ if (page != 0)
+ free_page(page);
+ } else {
+ /* XXX This needs to be fixed so that the ref and page are
+ placed on a list to be freed up later. */
+ printk(KERN_WARNING
+ "WARNING: leaking g.e. and page still in use!\n");
+ }
+}
+EXPORT_SYMBOL_GPL(gnttab_end_foreign_access);
+
+int gnttab_grant_foreign_transfer(domid_t domid, unsigned long pfn)
+{
+ int ref;
+
+ ref = get_free_entries(1);
+ if (unlikely(ref < 0))
+ return -ENOSPC;
+ gnttab_grant_foreign_transfer_ref(ref, domid, pfn);
+
+ return ref;
+}
+EXPORT_SYMBOL_GPL(gnttab_grant_foreign_transfer);
+
+void gnttab_grant_foreign_transfer_ref(grant_ref_t ref, domid_t domid,
+ unsigned long pfn)
+{
+ update_grant_entry(ref, domid, pfn, GTF_accept_transfer);
+}
+EXPORT_SYMBOL_GPL(gnttab_grant_foreign_transfer_ref);
+
+unsigned long gnttab_end_foreign_transfer_ref(grant_ref_t ref)
+{
+ unsigned long frame;
+ u16 flags;
+
+ /*
+ * If a transfer is not even yet started, try to reclaim the grant
+ * reference and return failure (== 0).
+ */
+ while (!((flags = shared[ref].flags) & GTF_transfer_committed)) {
+ if (sync_cmpxchg(&shared[ref].flags, flags, 0) == flags)
+ return 0;
+ cpu_relax();
+ }
+
+ /* If a transfer is in progress then wait until it is completed. */
+ while (!(flags & GTF_transfer_completed)) {
+ flags = shared[ref].flags;
+ cpu_relax();
+ }
+
+ rmb(); /* Read the frame number /after/ reading completion status. */
+ frame = shared[ref].frame;
+ BUG_ON(frame == 0);
+
+ return frame;
+}
+EXPORT_SYMBOL_GPL(gnttab_end_foreign_transfer_ref);
+
+unsigned long gnttab_end_foreign_transfer(grant_ref_t ref)
+{
+ unsigned long frame = gnttab_end_foreign_transfer_ref(ref);
+ put_free_entry(ref);
+ return frame;
+}
+EXPORT_SYMBOL_GPL(gnttab_end_foreign_transfer);
+
+void gnttab_free_grant_reference(grant_ref_t ref)
+{
+ put_free_entry(ref);
+}
+EXPORT_SYMBOL_GPL(gnttab_free_grant_reference);
+
+void gnttab_free_grant_references(grant_ref_t head)
+{
+ grant_ref_t ref;
+ unsigned long flags;
+ int count = 1;
+ if (head == GNTTAB_LIST_END)
+ return;
+ spin_lock_irqsave(&gnttab_list_lock, flags);
+ ref = head;
+ while (gnttab_entry(ref) != GNTTAB_LIST_END) {
+ ref = gnttab_entry(ref);
+ count++;
+ }
+ gnttab_entry(ref) = gnttab_free_head;
+ gnttab_free_head = head;
+ gnttab_free_count += count;
+ check_free_callbacks();
+ spin_unlock_irqrestore(&gnttab_list_lock, flags);
+}
+EXPORT_SYMBOL_GPL(gnttab_free_grant_references);
+
+int gnttab_alloc_grant_references(u16 count, grant_ref_t *head)
+{
+ int h = get_free_entries(count);
+
+ if (h < 0)
+ return -ENOSPC;
+
+ *head = h;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(gnttab_alloc_grant_references);
+
+int gnttab_empty_grant_references(const grant_ref_t *private_head)
+{
+ return (*private_head == GNTTAB_LIST_END);
+}
+EXPORT_SYMBOL_GPL(gnttab_empty_grant_references);
+
+int gnttab_claim_grant_reference(grant_ref_t *private_head)
+{
+ grant_ref_t g = *private_head;
+ if (unlikely(g == GNTTAB_LIST_END))
+ return -ENOSPC;
+ *private_head = gnttab_entry(g);
+ return g;
+}
+EXPORT_SYMBOL_GPL(gnttab_claim_grant_reference);
+
+void gnttab_release_grant_reference(grant_ref_t *private_head,
+ grant_ref_t release)
+{
+ gnttab_entry(release) = *private_head;
+ *private_head = release;
+}
+EXPORT_SYMBOL_GPL(gnttab_release_grant_reference);
+
+void gnttab_request_free_callback(struct gnttab_free_callback *callback,
+ void (*fn)(void *), void *arg, u16 count)
+{
+ unsigned long flags;
+ spin_lock_irqsave(&gnttab_list_lock, flags);
+ if (callback->next)
+ goto out;
+ callback->fn = fn;
+ callback->arg = arg;
+ callback->count = count;
+ callback->next = gnttab_free_callback_list;
+ gnttab_free_callback_list = callback;
+ check_free_callbacks();
+out:
+ spin_unlock_irqrestore(&gnttab_list_lock, flags);
+}
+EXPORT_SYMBOL_GPL(gnttab_request_free_callback);
+
+void gnttab_cancel_free_callback(struct gnttab_free_callback *callback)
+{
+ struct gnttab_free_callback **pcb;
+ unsigned long flags;
+
+ spin_lock_irqsave(&gnttab_list_lock, flags);
+ for (pcb = &gnttab_free_callback_list; *pcb; pcb = &(*pcb)->next) {
+ if (*pcb == callback) {
+ *pcb = callback->next;
+ break;
+ }
+ }
+ spin_unlock_irqrestore(&gnttab_list_lock, flags);
+}
+EXPORT_SYMBOL_GPL(gnttab_cancel_free_callback);
+
+static int grow_gnttab_list(unsigned int more_frames)
+{
+ unsigned int new_nr_grant_frames, extra_entries, i;
+ unsigned int nr_glist_frames, new_nr_glist_frames;
+
+ new_nr_grant_frames = nr_grant_frames + more_frames;
+ extra_entries = more_frames * GREFS_PER_GRANT_FRAME;
+
+ nr_glist_frames = (nr_grant_frames * GREFS_PER_GRANT_FRAME + RPP - 1) / RPP;
+ new_nr_glist_frames =
+ (new_nr_grant_frames * GREFS_PER_GRANT_FRAME + RPP - 1) / RPP;
+ for (i = nr_glist_frames; i < new_nr_glist_frames; i++) {
+ gnttab_list[i] = (grant_ref_t *)__get_free_page(GFP_ATOMIC);
+ if (!gnttab_list[i])
+ goto grow_nomem;
+ }
+
+
+ for (i = GREFS_PER_GRANT_FRAME * nr_grant_frames;
+ i < GREFS_PER_GRANT_FRAME * new_nr_grant_frames - 1; i++)
+ gnttab_entry(i) = i + 1;
+
+ gnttab_entry(i) = gnttab_free_head;
+ gnttab_free_head = GREFS_PER_GRANT_FRAME * nr_grant_frames;
+ gnttab_free_count += extra_entries;
+
+ nr_grant_frames = new_nr_grant_frames;
+
+ check_free_callbacks();
+
+ return 0;
+
+grow_nomem:
+ for ( ; i >= nr_glist_frames; i--)
+ free_page((unsigned long) gnttab_list[i]);
+ return -ENOMEM;
+}
+
+static unsigned int __max_nr_grant_frames(void)
+{
+ struct gnttab_query_size query;
+ int rc;
+
+ query.dom = DOMID_SELF;
+
+ rc = HYPERVISOR_grant_table_op(GNTTABOP_query_size, &query, 1);
+ if ((rc < 0) || (query.status != GNTST_okay))
+ return 4; /* Legacy max supported number of frames */
+
+ return query.max_nr_frames;
+}
+
+unsigned int gnttab_max_grant_frames(void)
+{
+ unsigned int xen_max = __max_nr_grant_frames();
+
+ if (xen_max > boot_max_nr_grant_frames)
+ return boot_max_nr_grant_frames;
+ return xen_max;
+}
+EXPORT_SYMBOL_GPL(gnttab_max_grant_frames);
+
+int gnttab_map_refs(struct gnttab_map_grant_ref *map_ops,
+ struct page **pages, unsigned int count)
+{
+ int i, ret;
+ pte_t *pte;
+ unsigned long mfn;
+
+ ret = HYPERVISOR_grant_table_op(GNTTABOP_map_grant_ref, map_ops, count);
+ if (ret)
+ return ret;
+
+ if (xen_feature(XENFEAT_auto_translated_physmap))
+ return ret;
+
+ for (i = 0; i < count; i++) {
+ /* Do not add to override if the map failed. */
+ if (map_ops[i].status)
+ continue;
+
+ if (map_ops[i].flags & GNTMAP_contains_pte) {
+ pte = (pte_t *) (mfn_to_virt(PFN_DOWN(map_ops[i].host_addr)) +
+ (map_ops[i].host_addr & ~PAGE_MASK));
+ mfn = pte_mfn(*pte);
+ } else {
+ /* If you really wanted to do this:
+ * mfn = PFN_DOWN(map_ops[i].dev_bus_addr);
+ *
+ * The reason we do not implement it is b/c on the
+ * unmap path (gnttab_unmap_refs) we have no means of
+ * checking whether the page is !GNTMAP_contains_pte.
+ *
+ * That is without some extra data-structure to carry
+ * the struct page, bool clear_pte, and list_head next
+ * tuples and deal with allocation/delallocation, etc.
+ *
+ * The users of this API set the GNTMAP_contains_pte
+ * flag so lets just return not supported until it
+ * becomes neccessary to implement.
+ */
+ return -EOPNOTSUPP;
+ }
+ ret = m2p_add_override(mfn, pages[i],
+ map_ops[i].flags & GNTMAP_contains_pte);
+ if (ret)
+ return ret;
+ }
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(gnttab_map_refs);
+
+int gnttab_unmap_refs(struct gnttab_unmap_grant_ref *unmap_ops,
+ struct page **pages, unsigned int count)
+{
+ int i, ret;
+
+ ret = HYPERVISOR_grant_table_op(GNTTABOP_unmap_grant_ref, unmap_ops, count);
+ if (ret)
+ return ret;
+
+ if (xen_feature(XENFEAT_auto_translated_physmap))
+ return ret;
+
+ for (i = 0; i < count; i++) {
+ ret = m2p_remove_override(pages[i], true /* clear the PTE */);
+ if (ret)
+ return ret;
+ }
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(gnttab_unmap_refs);
+
+static int gnttab_map(unsigned int start_idx, unsigned int end_idx)
+{
+ struct gnttab_setup_table setup;
+ unsigned long *frames;
+ unsigned int nr_gframes = end_idx + 1;
+ int rc;
+
+ if (xen_hvm_domain()) {
+ struct xen_add_to_physmap xatp;
+ unsigned int i = end_idx;
+ rc = 0;
+ /*
+ * Loop backwards, so that the first hypercall has the largest
+ * index, ensuring that the table will grow only once.
+ */
+ do {
+ xatp.domid = DOMID_SELF;
+ xatp.idx = i;
+ xatp.space = XENMAPSPACE_grant_table;
+ xatp.gpfn = (xen_hvm_resume_frames >> PAGE_SHIFT) + i;
+ rc = HYPERVISOR_memory_op(XENMEM_add_to_physmap, &xatp);
+ if (rc != 0) {
+ printk(KERN_WARNING
+ "grant table add_to_physmap failed, err=%d\n", rc);
+ break;
+ }
+ } while (i-- > start_idx);
+
+ return rc;
+ }
+
+ frames = kmalloc(nr_gframes * sizeof(unsigned long), GFP_ATOMIC);
+ if (!frames)
+ return -ENOMEM;
+
+ setup.dom = DOMID_SELF;
+ setup.nr_frames = nr_gframes;
+ set_xen_guest_handle(setup.frame_list, frames);
+
+ rc = HYPERVISOR_grant_table_op(GNTTABOP_setup_table, &setup, 1);
+ if (rc == -ENOSYS) {
+ kfree(frames);
+ return -ENOSYS;
+ }
+
+ BUG_ON(rc || setup.status);
+
+ rc = arch_gnttab_map_shared(frames, nr_gframes, gnttab_max_grant_frames(),
+ &shared);
+ BUG_ON(rc);
+
+ kfree(frames);
+
+ return 0;
+}
+
+int gnttab_resume(void)
+{
+ unsigned int max_nr_gframes;
+
+ max_nr_gframes = gnttab_max_grant_frames();
+ if (max_nr_gframes < nr_grant_frames)
+ return -ENOSYS;
+
+ if (xen_pv_domain())
+ return gnttab_map(0, nr_grant_frames - 1);
+
+ if (!shared) {
+ shared = ioremap(xen_hvm_resume_frames, PAGE_SIZE * max_nr_gframes);
+ if (shared == NULL) {
+ printk(KERN_WARNING
+ "Failed to ioremap gnttab share frames!");
+ return -ENOMEM;
+ }
+ }
+
+ gnttab_map(0, nr_grant_frames - 1);
+
+ return 0;
+}
+
+int gnttab_suspend(void)
+{
+ arch_gnttab_unmap_shared(shared, nr_grant_frames);
+ return 0;
+}
+
+static int gnttab_expand(unsigned int req_entries)
+{
+ int rc;
+ unsigned int cur, extra;
+
+ cur = nr_grant_frames;
+ extra = ((req_entries + (GREFS_PER_GRANT_FRAME-1)) /
+ GREFS_PER_GRANT_FRAME);
+ if (cur + extra > gnttab_max_grant_frames())
+ return -ENOSPC;
+
+ rc = gnttab_map(cur, cur + extra - 1);
+ if (rc == 0)
+ rc = grow_gnttab_list(extra);
+
+ return rc;
+}
+
+int gnttab_init(void)
+{
+ int i;
+ unsigned int max_nr_glist_frames, nr_glist_frames;
+ unsigned int nr_init_grefs;
+
+ nr_grant_frames = 1;
+ boot_max_nr_grant_frames = __max_nr_grant_frames();
+
+ /* Determine the maximum number of frames required for the
+ * grant reference free list on the current hypervisor.
+ */
+ max_nr_glist_frames = (boot_max_nr_grant_frames *
+ GREFS_PER_GRANT_FRAME / RPP);
+
+ gnttab_list = kmalloc(max_nr_glist_frames * sizeof(grant_ref_t *),
+ GFP_KERNEL);
+ if (gnttab_list == NULL)
+ return -ENOMEM;
+
+ nr_glist_frames = (nr_grant_frames * GREFS_PER_GRANT_FRAME + RPP - 1) / RPP;
+ for (i = 0; i < nr_glist_frames; i++) {
+ gnttab_list[i] = (grant_ref_t *)__get_free_page(GFP_KERNEL);
+ if (gnttab_list[i] == NULL)
+ goto ini_nomem;
+ }
+
+ if (gnttab_resume() < 0)
+ return -ENODEV;
+
+ nr_init_grefs = nr_grant_frames * GREFS_PER_GRANT_FRAME;
+
+ for (i = NR_RESERVED_ENTRIES; i < nr_init_grefs - 1; i++)
+ gnttab_entry(i) = i + 1;
+
+ gnttab_entry(nr_init_grefs - 1) = GNTTAB_LIST_END;
+ gnttab_free_count = nr_init_grefs - NR_RESERVED_ENTRIES;
+ gnttab_free_head = NR_RESERVED_ENTRIES;
+
+ printk("Grant table initialized\n");
+ return 0;
+
+ ini_nomem:
+ for (i--; i >= 0; i--)
+ free_page((unsigned long)gnttab_list[i]);
+ kfree(gnttab_list);
+ return -ENOMEM;
+}
+EXPORT_SYMBOL_GPL(gnttab_init);
+
+static int __devinit __gnttab_init(void)
+{
+ /* Delay grant-table initialization in the PV on HVM case */
+ if (xen_hvm_domain())
+ return 0;
+
+ if (!xen_pv_domain())
+ return -ENODEV;
+
+ return gnttab_init();
+}
+
+core_initcall(__gnttab_init);
diff --git a/drivers/xen/manage.c b/drivers/xen/manage.c
new file mode 100644
index 00000000..0b5366b5
--- /dev/null
+++ b/drivers/xen/manage.c
@@ -0,0 +1,337 @@
+/*
+ * Handle extern requests for shutdown, reboot and sysrq
+ */
+#include <linux/kernel.h>
+#include <linux/err.h>
+#include <linux/slab.h>
+#include <linux/reboot.h>
+#include <linux/sysrq.h>
+#include <linux/stop_machine.h>
+#include <linux/freezer.h>
+#include <linux/syscore_ops.h>
+
+#include <xen/xen.h>
+#include <xen/xenbus.h>
+#include <xen/grant_table.h>
+#include <xen/events.h>
+#include <xen/hvc-console.h>
+#include <xen/xen-ops.h>
+
+#include <asm/xen/hypercall.h>
+#include <asm/xen/page.h>
+#include <asm/xen/hypervisor.h>
+
+enum shutdown_state {
+ SHUTDOWN_INVALID = -1,
+ SHUTDOWN_POWEROFF = 0,
+ SHUTDOWN_SUSPEND = 2,
+ /* Code 3 is SHUTDOWN_CRASH, which we don't use because the domain can only
+ report a crash, not be instructed to crash!
+ HALT is the same as POWEROFF, as far as we're concerned. The tools use
+ the distinction when we return the reason code to them. */
+ SHUTDOWN_HALT = 4,
+};
+
+/* Ignore multiple shutdown requests. */
+static enum shutdown_state shutting_down = SHUTDOWN_INVALID;
+
+struct suspend_info {
+ int cancelled;
+ unsigned long arg; /* extra hypercall argument */
+ void (*pre)(void);
+ void (*post)(int cancelled);
+};
+
+static void xen_hvm_post_suspend(int cancelled)
+{
+ xen_arch_hvm_post_suspend(cancelled);
+ gnttab_resume();
+}
+
+static void xen_pre_suspend(void)
+{
+ xen_mm_pin_all();
+ gnttab_suspend();
+ xen_arch_pre_suspend();
+}
+
+static void xen_post_suspend(int cancelled)
+{
+ xen_arch_post_suspend(cancelled);
+ gnttab_resume();
+ xen_mm_unpin_all();
+}
+
+#ifdef CONFIG_HIBERNATE_CALLBACKS
+static int xen_suspend(void *data)
+{
+ struct suspend_info *si = data;
+ int err;
+
+ BUG_ON(!irqs_disabled());
+
+ err = syscore_suspend();
+ if (err) {
+ printk(KERN_ERR "xen_suspend: system core suspend failed: %d\n",
+ err);
+ return err;
+ }
+
+ if (si->pre)
+ si->pre();
+
+ /*
+ * This hypercall returns 1 if suspend was cancelled
+ * or the domain was merely checkpointed, and 0 if it
+ * is resuming in a new domain.
+ */
+ si->cancelled = HYPERVISOR_suspend(si->arg);
+
+ if (si->post)
+ si->post(si->cancelled);
+
+ if (!si->cancelled) {
+ xen_irq_resume();
+ xen_console_resume();
+ xen_timer_resume();
+ }
+
+ syscore_resume();
+
+ return 0;
+}
+
+static void do_suspend(void)
+{
+ int err;
+ struct suspend_info si;
+
+ shutting_down = SHUTDOWN_SUSPEND;
+
+#ifdef CONFIG_PREEMPT
+ /* If the kernel is preemptible, we need to freeze all the processes
+ to prevent them from being in the middle of a pagetable update
+ during suspend. */
+ err = freeze_processes();
+ if (err) {
+ printk(KERN_ERR "xen suspend: freeze failed %d\n", err);
+ goto out;
+ }
+#endif
+
+ err = dpm_suspend_start(PMSG_FREEZE);
+ if (err) {
+ printk(KERN_ERR "xen suspend: dpm_suspend_start %d\n", err);
+ goto out_thaw;
+ }
+
+ printk(KERN_DEBUG "suspending xenstore...\n");
+ xs_suspend();
+
+ err = dpm_suspend_noirq(PMSG_FREEZE);
+ if (err) {
+ printk(KERN_ERR "dpm_suspend_noirq failed: %d\n", err);
+ goto out_resume;
+ }
+
+ si.cancelled = 1;
+
+ if (xen_hvm_domain()) {
+ si.arg = 0UL;
+ si.pre = NULL;
+ si.post = &xen_hvm_post_suspend;
+ } else {
+ si.arg = virt_to_mfn(xen_start_info);
+ si.pre = &xen_pre_suspend;
+ si.post = &xen_post_suspend;
+ }
+
+ err = stop_machine(xen_suspend, &si, cpumask_of(0));
+
+ dpm_resume_noirq(si.cancelled ? PMSG_THAW : PMSG_RESTORE);
+
+ if (err) {
+ printk(KERN_ERR "failed to start xen_suspend: %d\n", err);
+ si.cancelled = 1;
+ }
+
+out_resume:
+ if (!si.cancelled) {
+ xen_arch_resume();
+ xs_resume();
+ } else
+ xs_suspend_cancel();
+
+ dpm_resume_end(si.cancelled ? PMSG_THAW : PMSG_RESTORE);
+
+ /* Make sure timer events get retriggered on all CPUs */
+ clock_was_set();
+
+out_thaw:
+#ifdef CONFIG_PREEMPT
+ thaw_processes();
+out:
+#endif
+ shutting_down = SHUTDOWN_INVALID;
+}
+#endif /* CONFIG_HIBERNATE_CALLBACKS */
+
+struct shutdown_handler {
+ const char *command;
+ void (*cb)(void);
+};
+
+static void do_poweroff(void)
+{
+ shutting_down = SHUTDOWN_POWEROFF;
+ orderly_poweroff(false);
+}
+
+static void do_reboot(void)
+{
+ shutting_down = SHUTDOWN_POWEROFF; /* ? */
+ ctrl_alt_del();
+}
+
+static void shutdown_handler(struct xenbus_watch *watch,
+ const char **vec, unsigned int len)
+{
+ char *str;
+ struct xenbus_transaction xbt;
+ int err;
+ static struct shutdown_handler handlers[] = {
+ { "poweroff", do_poweroff },
+ { "halt", do_poweroff },
+ { "reboot", do_reboot },
+#ifdef CONFIG_HIBERNATE_CALLBACKS
+ { "suspend", do_suspend },
+#endif
+ {NULL, NULL},
+ };
+ static struct shutdown_handler *handler;
+
+ if (shutting_down != SHUTDOWN_INVALID)
+ return;
+
+ again:
+ err = xenbus_transaction_start(&xbt);
+ if (err)
+ return;
+
+ str = (char *)xenbus_read(xbt, "control", "shutdown", NULL);
+ /* Ignore read errors and empty reads. */
+ if (XENBUS_IS_ERR_READ(str)) {
+ xenbus_transaction_end(xbt, 1);
+ return;
+ }
+
+ for (handler = &handlers[0]; handler->command; handler++) {
+ if (strcmp(str, handler->command) == 0)
+ break;
+ }
+
+ /* Only acknowledge commands which we are prepared to handle. */
+ if (handler->cb)
+ xenbus_write(xbt, "control", "shutdown", "");
+
+ err = xenbus_transaction_end(xbt, 0);
+ if (err == -EAGAIN) {
+ kfree(str);
+ goto again;
+ }
+
+ if (handler->cb) {
+ handler->cb();
+ } else {
+ printk(KERN_INFO "Ignoring shutdown request: %s\n", str);
+ shutting_down = SHUTDOWN_INVALID;
+ }
+
+ kfree(str);
+}
+
+#ifdef CONFIG_MAGIC_SYSRQ
+static void sysrq_handler(struct xenbus_watch *watch, const char **vec,
+ unsigned int len)
+{
+ char sysrq_key = '\0';
+ struct xenbus_transaction xbt;
+ int err;
+
+ again:
+ err = xenbus_transaction_start(&xbt);
+ if (err)
+ return;
+ if (!xenbus_scanf(xbt, "control", "sysrq", "%c", &sysrq_key)) {
+ printk(KERN_ERR "Unable to read sysrq code in "
+ "control/sysrq\n");
+ xenbus_transaction_end(xbt, 1);
+ return;
+ }
+
+ if (sysrq_key != '\0')
+ xenbus_printf(xbt, "control", "sysrq", "%c", '\0');
+
+ err = xenbus_transaction_end(xbt, 0);
+ if (err == -EAGAIN)
+ goto again;
+
+ if (sysrq_key != '\0')
+ handle_sysrq(sysrq_key);
+}
+
+static struct xenbus_watch sysrq_watch = {
+ .node = "control/sysrq",
+ .callback = sysrq_handler
+};
+#endif
+
+static struct xenbus_watch shutdown_watch = {
+ .node = "control/shutdown",
+ .callback = shutdown_handler
+};
+
+static int setup_shutdown_watcher(void)
+{
+ int err;
+
+ err = register_xenbus_watch(&shutdown_watch);
+ if (err) {
+ printk(KERN_ERR "Failed to set shutdown watcher\n");
+ return err;
+ }
+
+#ifdef CONFIG_MAGIC_SYSRQ
+ err = register_xenbus_watch(&sysrq_watch);
+ if (err) {
+ printk(KERN_ERR "Failed to set sysrq watcher\n");
+ return err;
+ }
+#endif
+
+ return 0;
+}
+
+static int shutdown_event(struct notifier_block *notifier,
+ unsigned long event,
+ void *data)
+{
+ setup_shutdown_watcher();
+ return NOTIFY_DONE;
+}
+
+int xen_setup_shutdown_event(void)
+{
+ static struct notifier_block xenstore_notifier = {
+ .notifier_call = shutdown_event
+ };
+
+ if (!xen_domain())
+ return -ENODEV;
+ register_xenstore_notifier(&xenstore_notifier);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(xen_setup_shutdown_event);
+
+subsys_initcall(xen_setup_shutdown_event);
diff --git a/drivers/xen/pci.c b/drivers/xen/pci.c
new file mode 100644
index 00000000..cef4bafc
--- /dev/null
+++ b/drivers/xen/pci.c
@@ -0,0 +1,117 @@
+/*
+ * Copyright (c) 2009, Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place - Suite 330, Boston, MA 02111-1307 USA.
+ *
+ * Author: Weidong Han <weidong.han@intel.com>
+ */
+
+#include <linux/pci.h>
+#include <xen/xen.h>
+#include <xen/interface/physdev.h>
+#include <xen/interface/xen.h>
+
+#include <asm/xen/hypervisor.h>
+#include <asm/xen/hypercall.h>
+#include "../pci/pci.h"
+
+static int xen_add_device(struct device *dev)
+{
+ int r;
+ struct pci_dev *pci_dev = to_pci_dev(dev);
+
+#ifdef CONFIG_PCI_IOV
+ if (pci_dev->is_virtfn) {
+ struct physdev_manage_pci_ext manage_pci_ext = {
+ .bus = pci_dev->bus->number,
+ .devfn = pci_dev->devfn,
+ .is_virtfn = 1,
+ .physfn.bus = pci_dev->physfn->bus->number,
+ .physfn.devfn = pci_dev->physfn->devfn,
+ };
+
+ r = HYPERVISOR_physdev_op(PHYSDEVOP_manage_pci_add_ext,
+ &manage_pci_ext);
+ } else
+#endif
+ if (pci_ari_enabled(pci_dev->bus) && PCI_SLOT(pci_dev->devfn)) {
+ struct physdev_manage_pci_ext manage_pci_ext = {
+ .bus = pci_dev->bus->number,
+ .devfn = pci_dev->devfn,
+ .is_extfn = 1,
+ };
+
+ r = HYPERVISOR_physdev_op(PHYSDEVOP_manage_pci_add_ext,
+ &manage_pci_ext);
+ } else {
+ struct physdev_manage_pci manage_pci = {
+ .bus = pci_dev->bus->number,
+ .devfn = pci_dev->devfn,
+ };
+
+ r = HYPERVISOR_physdev_op(PHYSDEVOP_manage_pci_add,
+ &manage_pci);
+ }
+
+ return r;
+}
+
+static int xen_remove_device(struct device *dev)
+{
+ int r;
+ struct pci_dev *pci_dev = to_pci_dev(dev);
+ struct physdev_manage_pci manage_pci;
+
+ manage_pci.bus = pci_dev->bus->number;
+ manage_pci.devfn = pci_dev->devfn;
+
+ r = HYPERVISOR_physdev_op(PHYSDEVOP_manage_pci_remove,
+ &manage_pci);
+
+ return r;
+}
+
+static int xen_pci_notifier(struct notifier_block *nb,
+ unsigned long action, void *data)
+{
+ struct device *dev = data;
+ int r = 0;
+
+ switch (action) {
+ case BUS_NOTIFY_ADD_DEVICE:
+ r = xen_add_device(dev);
+ break;
+ case BUS_NOTIFY_DEL_DEVICE:
+ r = xen_remove_device(dev);
+ break;
+ default:
+ break;
+ }
+
+ return r;
+}
+
+struct notifier_block device_nb = {
+ .notifier_call = xen_pci_notifier,
+};
+
+static int __init register_xen_pci_notifier(void)
+{
+ if (!xen_initial_domain())
+ return 0;
+
+ return bus_register_notifier(&pci_bus_type, &device_nb);
+}
+
+arch_initcall(register_xen_pci_notifier);
diff --git a/drivers/xen/platform-pci.c b/drivers/xen/platform-pci.c
new file mode 100644
index 00000000..319dd0a9
--- /dev/null
+++ b/drivers/xen/platform-pci.c
@@ -0,0 +1,197 @@
+/******************************************************************************
+ * platform-pci.c
+ *
+ * Xen platform PCI device driver
+ * Copyright (c) 2005, Intel Corporation.
+ * Copyright (c) 2007, XenSource Inc.
+ * Copyright (c) 2010, Citrix
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place - Suite 330, Boston, MA 02111-1307 USA.
+ *
+ */
+
+
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+
+#include <xen/platform_pci.h>
+#include <xen/grant_table.h>
+#include <xen/xenbus.h>
+#include <xen/events.h>
+#include <xen/hvm.h>
+#include <xen/xen-ops.h>
+
+#define DRV_NAME "xen-platform-pci"
+
+MODULE_AUTHOR("ssmith@xensource.com and stefano.stabellini@eu.citrix.com");
+MODULE_DESCRIPTION("Xen platform PCI device");
+MODULE_LICENSE("GPL");
+
+static unsigned long platform_mmio;
+static unsigned long platform_mmio_alloc;
+static unsigned long platform_mmiolen;
+static uint64_t callback_via;
+
+unsigned long alloc_xen_mmio(unsigned long len)
+{
+ unsigned long addr;
+
+ addr = platform_mmio + platform_mmio_alloc;
+ platform_mmio_alloc += len;
+ BUG_ON(platform_mmio_alloc > platform_mmiolen);
+
+ return addr;
+}
+
+static uint64_t get_callback_via(struct pci_dev *pdev)
+{
+ u8 pin;
+ int irq;
+
+ irq = pdev->irq;
+ if (irq < 16)
+ return irq; /* ISA IRQ */
+
+ pin = pdev->pin;
+
+ /* We don't know the GSI. Specify the PCI INTx line instead. */
+ return ((uint64_t)0x01 << 56) | /* PCI INTx identifier */
+ ((uint64_t)pci_domain_nr(pdev->bus) << 32) |
+ ((uint64_t)pdev->bus->number << 16) |
+ ((uint64_t)(pdev->devfn & 0xff) << 8) |
+ ((uint64_t)(pin - 1) & 3);
+}
+
+static irqreturn_t do_hvm_evtchn_intr(int irq, void *dev_id)
+{
+ xen_hvm_evtchn_do_upcall();
+ return IRQ_HANDLED;
+}
+
+static int xen_allocate_irq(struct pci_dev *pdev)
+{
+ return request_irq(pdev->irq, do_hvm_evtchn_intr,
+ IRQF_DISABLED | IRQF_NOBALANCING | IRQF_TRIGGER_RISING,
+ "xen-platform-pci", pdev);
+}
+
+static int platform_pci_resume(struct pci_dev *pdev)
+{
+ int err;
+ if (xen_have_vector_callback)
+ return 0;
+ err = xen_set_callback_via(callback_via);
+ if (err) {
+ dev_err(&pdev->dev, "platform_pci_resume failure!\n");
+ return err;
+ }
+ return 0;
+}
+
+static int __devinit platform_pci_init(struct pci_dev *pdev,
+ const struct pci_device_id *ent)
+{
+ int i, ret;
+ long ioaddr;
+ long mmio_addr, mmio_len;
+ unsigned int max_nr_gframes;
+
+ i = pci_enable_device(pdev);
+ if (i)
+ return i;
+
+ ioaddr = pci_resource_start(pdev, 0);
+
+ mmio_addr = pci_resource_start(pdev, 1);
+ mmio_len = pci_resource_len(pdev, 1);
+
+ if (mmio_addr == 0 || ioaddr == 0) {
+ dev_err(&pdev->dev, "no resources found\n");
+ ret = -ENOENT;
+ goto pci_out;
+ }
+
+ ret = pci_request_region(pdev, 1, DRV_NAME);
+ if (ret < 0)
+ goto pci_out;
+
+ ret = pci_request_region(pdev, 0, DRV_NAME);
+ if (ret < 0)
+ goto mem_out;
+
+ platform_mmio = mmio_addr;
+ platform_mmiolen = mmio_len;
+
+ if (!xen_have_vector_callback) {
+ ret = xen_allocate_irq(pdev);
+ if (ret) {
+ dev_warn(&pdev->dev, "request_irq failed err=%d\n", ret);
+ goto out;
+ }
+ callback_via = get_callback_via(pdev);
+ ret = xen_set_callback_via(callback_via);
+ if (ret) {
+ dev_warn(&pdev->dev, "Unable to set the evtchn callback "
+ "err=%d\n", ret);
+ goto out;
+ }
+ }
+
+ max_nr_gframes = gnttab_max_grant_frames();
+ xen_hvm_resume_frames = alloc_xen_mmio(PAGE_SIZE * max_nr_gframes);
+ ret = gnttab_init();
+ if (ret)
+ goto out;
+ xenbus_probe(NULL);
+ return 0;
+
+out:
+ pci_release_region(pdev, 0);
+mem_out:
+ pci_release_region(pdev, 1);
+pci_out:
+ pci_disable_device(pdev);
+ return ret;
+}
+
+static struct pci_device_id platform_pci_tbl[] __devinitdata = {
+ {PCI_VENDOR_ID_XEN, PCI_DEVICE_ID_XEN_PLATFORM,
+ PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0},
+ {0,}
+};
+
+MODULE_DEVICE_TABLE(pci, platform_pci_tbl);
+
+static struct pci_driver platform_driver = {
+ .name = DRV_NAME,
+ .probe = platform_pci_init,
+ .id_table = platform_pci_tbl,
+#ifdef CONFIG_PM
+ .resume_early = platform_pci_resume,
+#endif
+};
+
+static int __init platform_pci_module_init(void)
+{
+ /* no unplug has been done, IGNORE hasn't been specified: just
+ * return now */
+ if (!xen_platform_pci_unplug)
+ return -ENODEV;
+
+ return pci_register_driver(&platform_driver);
+}
+
+module_init(platform_pci_module_init);
diff --git a/drivers/xen/swiotlb-xen.c b/drivers/xen/swiotlb-xen.c
new file mode 100644
index 00000000..fd60dffe
--- /dev/null
+++ b/drivers/xen/swiotlb-xen.c
@@ -0,0 +1,522 @@
+/*
+ * Copyright 2010
+ * by Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
+ *
+ * This code provides a IOMMU for Xen PV guests with PCI passthrough.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License v2.0 as published by
+ * the Free Software Foundation
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * PV guests under Xen are running in an non-contiguous memory architecture.
+ *
+ * When PCI pass-through is utilized, this necessitates an IOMMU for
+ * translating bus (DMA) to virtual and vice-versa and also providing a
+ * mechanism to have contiguous pages for device drivers operations (say DMA
+ * operations).
+ *
+ * Specifically, under Xen the Linux idea of pages is an illusion. It
+ * assumes that pages start at zero and go up to the available memory. To
+ * help with that, the Linux Xen MMU provides a lookup mechanism to
+ * translate the page frame numbers (PFN) to machine frame numbers (MFN)
+ * and vice-versa. The MFN are the "real" frame numbers. Furthermore
+ * memory is not contiguous. Xen hypervisor stitches memory for guests
+ * from different pools, which means there is no guarantee that PFN==MFN
+ * and PFN+1==MFN+1. Lastly with Xen 4.0, pages (in debug mode) are
+ * allocated in descending order (high to low), meaning the guest might
+ * never get any MFN's under the 4GB mark.
+ *
+ */
+
+#include <linux/bootmem.h>
+#include <linux/dma-mapping.h>
+#include <xen/swiotlb-xen.h>
+#include <xen/page.h>
+#include <xen/xen-ops.h>
+/*
+ * Used to do a quick range check in swiotlb_tbl_unmap_single and
+ * swiotlb_tbl_sync_single_*, to see if the memory was in fact allocated by this
+ * API.
+ */
+
+static char *xen_io_tlb_start, *xen_io_tlb_end;
+static unsigned long xen_io_tlb_nslabs;
+/*
+ * Quick lookup value of the bus address of the IOTLB.
+ */
+
+u64 start_dma_addr;
+
+static dma_addr_t xen_phys_to_bus(phys_addr_t paddr)
+{
+ return phys_to_machine(XPADDR(paddr)).maddr;
+}
+
+static phys_addr_t xen_bus_to_phys(dma_addr_t baddr)
+{
+ return machine_to_phys(XMADDR(baddr)).paddr;
+}
+
+static dma_addr_t xen_virt_to_bus(void *address)
+{
+ return xen_phys_to_bus(virt_to_phys(address));
+}
+
+static int check_pages_physically_contiguous(unsigned long pfn,
+ unsigned int offset,
+ size_t length)
+{
+ unsigned long next_mfn;
+ int i;
+ int nr_pages;
+
+ next_mfn = pfn_to_mfn(pfn);
+ nr_pages = (offset + length + PAGE_SIZE-1) >> PAGE_SHIFT;
+
+ for (i = 1; i < nr_pages; i++) {
+ if (pfn_to_mfn(++pfn) != ++next_mfn)
+ return 0;
+ }
+ return 1;
+}
+
+static int range_straddles_page_boundary(phys_addr_t p, size_t size)
+{
+ unsigned long pfn = PFN_DOWN(p);
+ unsigned int offset = p & ~PAGE_MASK;
+
+ if (offset + size <= PAGE_SIZE)
+ return 0;
+ if (check_pages_physically_contiguous(pfn, offset, size))
+ return 0;
+ return 1;
+}
+
+static int is_xen_swiotlb_buffer(dma_addr_t dma_addr)
+{
+ unsigned long mfn = PFN_DOWN(dma_addr);
+ unsigned long pfn = mfn_to_local_pfn(mfn);
+ phys_addr_t paddr;
+
+ /* If the address is outside our domain, it CAN
+ * have the same virtual address as another address
+ * in our domain. Therefore _only_ check address within our domain.
+ */
+ if (pfn_valid(pfn)) {
+ paddr = PFN_PHYS(pfn);
+ return paddr >= virt_to_phys(xen_io_tlb_start) &&
+ paddr < virt_to_phys(xen_io_tlb_end);
+ }
+ return 0;
+}
+
+static int max_dma_bits = 32;
+
+static int
+xen_swiotlb_fixup(void *buf, size_t size, unsigned long nslabs)
+{
+ int i, rc;
+ int dma_bits;
+
+ dma_bits = get_order(IO_TLB_SEGSIZE << IO_TLB_SHIFT) + PAGE_SHIFT;
+
+ i = 0;
+ do {
+ int slabs = min(nslabs - i, (unsigned long)IO_TLB_SEGSIZE);
+
+ do {
+ rc = xen_create_contiguous_region(
+ (unsigned long)buf + (i << IO_TLB_SHIFT),
+ get_order(slabs << IO_TLB_SHIFT),
+ dma_bits);
+ } while (rc && dma_bits++ < max_dma_bits);
+ if (rc)
+ return rc;
+
+ i += slabs;
+ } while (i < nslabs);
+ return 0;
+}
+
+void __init xen_swiotlb_init(int verbose)
+{
+ unsigned long bytes;
+ int rc;
+ unsigned long nr_tbl;
+
+ nr_tbl = swioltb_nr_tbl();
+ if (nr_tbl)
+ xen_io_tlb_nslabs = nr_tbl;
+ else {
+ xen_io_tlb_nslabs = (64 * 1024 * 1024 >> IO_TLB_SHIFT);
+ xen_io_tlb_nslabs = ALIGN(xen_io_tlb_nslabs, IO_TLB_SEGSIZE);
+ }
+
+ bytes = xen_io_tlb_nslabs << IO_TLB_SHIFT;
+
+ /*
+ * Get IO TLB memory from any location.
+ */
+ xen_io_tlb_start = alloc_bootmem_pages(PAGE_ALIGN(bytes));
+ if (!xen_io_tlb_start)
+ panic("Cannot allocate SWIOTLB buffer");
+
+ xen_io_tlb_end = xen_io_tlb_start + bytes;
+ /*
+ * And replace that memory with pages under 4GB.
+ */
+ rc = xen_swiotlb_fixup(xen_io_tlb_start,
+ bytes,
+ xen_io_tlb_nslabs);
+ if (rc)
+ goto error;
+
+ start_dma_addr = xen_virt_to_bus(xen_io_tlb_start);
+ swiotlb_init_with_tbl(xen_io_tlb_start, xen_io_tlb_nslabs, verbose);
+
+ return;
+error:
+ panic("DMA(%d): Failed to exchange pages allocated for DMA with Xen! "\
+ "We either don't have the permission or you do not have enough"\
+ "free memory under 4GB!\n", rc);
+}
+
+void *
+xen_swiotlb_alloc_coherent(struct device *hwdev, size_t size,
+ dma_addr_t *dma_handle, gfp_t flags)
+{
+ void *ret;
+ int order = get_order(size);
+ u64 dma_mask = DMA_BIT_MASK(32);
+ unsigned long vstart;
+
+ /*
+ * Ignore region specifiers - the kernel's ideas of
+ * pseudo-phys memory layout has nothing to do with the
+ * machine physical layout. We can't allocate highmem
+ * because we can't return a pointer to it.
+ */
+ flags &= ~(__GFP_DMA | __GFP_HIGHMEM);
+
+ if (dma_alloc_from_coherent(hwdev, size, dma_handle, &ret))
+ return ret;
+
+ vstart = __get_free_pages(flags, order);
+ ret = (void *)vstart;
+
+ if (hwdev && hwdev->coherent_dma_mask)
+ dma_mask = dma_alloc_coherent_mask(hwdev, flags);
+
+ if (ret) {
+ if (xen_create_contiguous_region(vstart, order,
+ fls64(dma_mask)) != 0) {
+ free_pages(vstart, order);
+ return NULL;
+ }
+ memset(ret, 0, size);
+ *dma_handle = virt_to_machine(ret).maddr;
+ }
+ return ret;
+}
+EXPORT_SYMBOL_GPL(xen_swiotlb_alloc_coherent);
+
+void
+xen_swiotlb_free_coherent(struct device *hwdev, size_t size, void *vaddr,
+ dma_addr_t dev_addr)
+{
+ int order = get_order(size);
+
+ if (dma_release_from_coherent(hwdev, order, vaddr))
+ return;
+
+ xen_destroy_contiguous_region((unsigned long)vaddr, order);
+ free_pages((unsigned long)vaddr, order);
+}
+EXPORT_SYMBOL_GPL(xen_swiotlb_free_coherent);
+
+
+/*
+ * Map a single buffer of the indicated size for DMA in streaming mode. The
+ * physical address to use is returned.
+ *
+ * Once the device is given the dma address, the device owns this memory until
+ * either xen_swiotlb_unmap_page or xen_swiotlb_dma_sync_single is performed.
+ */
+dma_addr_t xen_swiotlb_map_page(struct device *dev, struct page *page,
+ unsigned long offset, size_t size,
+ enum dma_data_direction dir,
+ struct dma_attrs *attrs)
+{
+ phys_addr_t phys = page_to_phys(page) + offset;
+ dma_addr_t dev_addr = xen_phys_to_bus(phys);
+ void *map;
+
+ BUG_ON(dir == DMA_NONE);
+ /*
+ * If the address happens to be in the device's DMA window,
+ * we can safely return the device addr and not worry about bounce
+ * buffering it.
+ */
+ if (dma_capable(dev, dev_addr, size) &&
+ !range_straddles_page_boundary(phys, size) && !swiotlb_force)
+ return dev_addr;
+
+ /*
+ * Oh well, have to allocate and map a bounce buffer.
+ */
+ map = swiotlb_tbl_map_single(dev, start_dma_addr, phys, size, dir);
+ if (!map)
+ return DMA_ERROR_CODE;
+
+ dev_addr = xen_virt_to_bus(map);
+
+ /*
+ * Ensure that the address returned is DMA'ble
+ */
+ if (!dma_capable(dev, dev_addr, size)) {
+ swiotlb_tbl_unmap_single(dev, map, size, dir);
+ dev_addr = 0;
+ }
+ return dev_addr;
+}
+EXPORT_SYMBOL_GPL(xen_swiotlb_map_page);
+
+/*
+ * Unmap a single streaming mode DMA translation. The dma_addr and size must
+ * match what was provided for in a previous xen_swiotlb_map_page call. All
+ * other usages are undefined.
+ *
+ * After this call, reads by the cpu to the buffer are guaranteed to see
+ * whatever the device wrote there.
+ */
+static void xen_unmap_single(struct device *hwdev, dma_addr_t dev_addr,
+ size_t size, enum dma_data_direction dir)
+{
+ phys_addr_t paddr = xen_bus_to_phys(dev_addr);
+
+ BUG_ON(dir == DMA_NONE);
+
+ /* NOTE: We use dev_addr here, not paddr! */
+ if (is_xen_swiotlb_buffer(dev_addr)) {
+ swiotlb_tbl_unmap_single(hwdev, phys_to_virt(paddr), size, dir);
+ return;
+ }
+
+ if (dir != DMA_FROM_DEVICE)
+ return;
+
+ /*
+ * phys_to_virt doesn't work with hihgmem page but we could
+ * call dma_mark_clean() with hihgmem page here. However, we
+ * are fine since dma_mark_clean() is null on POWERPC. We can
+ * make dma_mark_clean() take a physical address if necessary.
+ */
+ dma_mark_clean(phys_to_virt(paddr), size);
+}
+
+void xen_swiotlb_unmap_page(struct device *hwdev, dma_addr_t dev_addr,
+ size_t size, enum dma_data_direction dir,
+ struct dma_attrs *attrs)
+{
+ xen_unmap_single(hwdev, dev_addr, size, dir);
+}
+EXPORT_SYMBOL_GPL(xen_swiotlb_unmap_page);
+
+/*
+ * Make physical memory consistent for a single streaming mode DMA translation
+ * after a transfer.
+ *
+ * If you perform a xen_swiotlb_map_page() but wish to interrogate the buffer
+ * using the cpu, yet do not wish to teardown the dma mapping, you must
+ * call this function before doing so. At the next point you give the dma
+ * address back to the card, you must first perform a
+ * xen_swiotlb_dma_sync_for_device, and then the device again owns the buffer
+ */
+static void
+xen_swiotlb_sync_single(struct device *hwdev, dma_addr_t dev_addr,
+ size_t size, enum dma_data_direction dir,
+ enum dma_sync_target target)
+{
+ phys_addr_t paddr = xen_bus_to_phys(dev_addr);
+
+ BUG_ON(dir == DMA_NONE);
+
+ /* NOTE: We use dev_addr here, not paddr! */
+ if (is_xen_swiotlb_buffer(dev_addr)) {
+ swiotlb_tbl_sync_single(hwdev, phys_to_virt(paddr), size, dir,
+ target);
+ return;
+ }
+
+ if (dir != DMA_FROM_DEVICE)
+ return;
+
+ dma_mark_clean(phys_to_virt(paddr), size);
+}
+
+void
+xen_swiotlb_sync_single_for_cpu(struct device *hwdev, dma_addr_t dev_addr,
+ size_t size, enum dma_data_direction dir)
+{
+ xen_swiotlb_sync_single(hwdev, dev_addr, size, dir, SYNC_FOR_CPU);
+}
+EXPORT_SYMBOL_GPL(xen_swiotlb_sync_single_for_cpu);
+
+void
+xen_swiotlb_sync_single_for_device(struct device *hwdev, dma_addr_t dev_addr,
+ size_t size, enum dma_data_direction dir)
+{
+ xen_swiotlb_sync_single(hwdev, dev_addr, size, dir, SYNC_FOR_DEVICE);
+}
+EXPORT_SYMBOL_GPL(xen_swiotlb_sync_single_for_device);
+
+/*
+ * Map a set of buffers described by scatterlist in streaming mode for DMA.
+ * This is the scatter-gather version of the above xen_swiotlb_map_page
+ * interface. Here the scatter gather list elements are each tagged with the
+ * appropriate dma address and length. They are obtained via
+ * sg_dma_{address,length}(SG).
+ *
+ * NOTE: An implementation may be able to use a smaller number of
+ * DMA address/length pairs than there are SG table elements.
+ * (for example via virtual mapping capabilities)
+ * The routine returns the number of addr/length pairs actually
+ * used, at most nents.
+ *
+ * Device ownership issues as mentioned above for xen_swiotlb_map_page are the
+ * same here.
+ */
+int
+xen_swiotlb_map_sg_attrs(struct device *hwdev, struct scatterlist *sgl,
+ int nelems, enum dma_data_direction dir,
+ struct dma_attrs *attrs)
+{
+ struct scatterlist *sg;
+ int i;
+
+ BUG_ON(dir == DMA_NONE);
+
+ for_each_sg(sgl, sg, nelems, i) {
+ phys_addr_t paddr = sg_phys(sg);
+ dma_addr_t dev_addr = xen_phys_to_bus(paddr);
+
+ if (swiotlb_force ||
+ !dma_capable(hwdev, dev_addr, sg->length) ||
+ range_straddles_page_boundary(paddr, sg->length)) {
+ void *map = swiotlb_tbl_map_single(hwdev,
+ start_dma_addr,
+ sg_phys(sg),
+ sg->length, dir);
+ if (!map) {
+ /* Don't panic here, we expect map_sg users
+ to do proper error handling. */
+ xen_swiotlb_unmap_sg_attrs(hwdev, sgl, i, dir,
+ attrs);
+ sgl[0].dma_length = 0;
+ return DMA_ERROR_CODE;
+ }
+ sg->dma_address = xen_virt_to_bus(map);
+ } else
+ sg->dma_address = dev_addr;
+ sg->dma_length = sg->length;
+ }
+ return nelems;
+}
+EXPORT_SYMBOL_GPL(xen_swiotlb_map_sg_attrs);
+
+int
+xen_swiotlb_map_sg(struct device *hwdev, struct scatterlist *sgl, int nelems,
+ enum dma_data_direction dir)
+{
+ return xen_swiotlb_map_sg_attrs(hwdev, sgl, nelems, dir, NULL);
+}
+EXPORT_SYMBOL_GPL(xen_swiotlb_map_sg);
+
+/*
+ * Unmap a set of streaming mode DMA translations. Again, cpu read rules
+ * concerning calls here are the same as for swiotlb_unmap_page() above.
+ */
+void
+xen_swiotlb_unmap_sg_attrs(struct device *hwdev, struct scatterlist *sgl,
+ int nelems, enum dma_data_direction dir,
+ struct dma_attrs *attrs)
+{
+ struct scatterlist *sg;
+ int i;
+
+ BUG_ON(dir == DMA_NONE);
+
+ for_each_sg(sgl, sg, nelems, i)
+ xen_unmap_single(hwdev, sg->dma_address, sg->dma_length, dir);
+
+}
+EXPORT_SYMBOL_GPL(xen_swiotlb_unmap_sg_attrs);
+
+void
+xen_swiotlb_unmap_sg(struct device *hwdev, struct scatterlist *sgl, int nelems,
+ enum dma_data_direction dir)
+{
+ return xen_swiotlb_unmap_sg_attrs(hwdev, sgl, nelems, dir, NULL);
+}
+EXPORT_SYMBOL_GPL(xen_swiotlb_unmap_sg);
+
+/*
+ * Make physical memory consistent for a set of streaming mode DMA translations
+ * after a transfer.
+ *
+ * The same as swiotlb_sync_single_* but for a scatter-gather list, same rules
+ * and usage.
+ */
+static void
+xen_swiotlb_sync_sg(struct device *hwdev, struct scatterlist *sgl,
+ int nelems, enum dma_data_direction dir,
+ enum dma_sync_target target)
+{
+ struct scatterlist *sg;
+ int i;
+
+ for_each_sg(sgl, sg, nelems, i)
+ xen_swiotlb_sync_single(hwdev, sg->dma_address,
+ sg->dma_length, dir, target);
+}
+
+void
+xen_swiotlb_sync_sg_for_cpu(struct device *hwdev, struct scatterlist *sg,
+ int nelems, enum dma_data_direction dir)
+{
+ xen_swiotlb_sync_sg(hwdev, sg, nelems, dir, SYNC_FOR_CPU);
+}
+EXPORT_SYMBOL_GPL(xen_swiotlb_sync_sg_for_cpu);
+
+void
+xen_swiotlb_sync_sg_for_device(struct device *hwdev, struct scatterlist *sg,
+ int nelems, enum dma_data_direction dir)
+{
+ xen_swiotlb_sync_sg(hwdev, sg, nelems, dir, SYNC_FOR_DEVICE);
+}
+EXPORT_SYMBOL_GPL(xen_swiotlb_sync_sg_for_device);
+
+int
+xen_swiotlb_dma_mapping_error(struct device *hwdev, dma_addr_t dma_addr)
+{
+ return !dma_addr;
+}
+EXPORT_SYMBOL_GPL(xen_swiotlb_dma_mapping_error);
+
+/*
+ * Return whether the given device DMA address mask can be supported
+ * properly. For example, if your device can only drive the low 24-bits
+ * during bus mastering, then you would pass 0x00ffffff as the mask to
+ * this function.
+ */
+int
+xen_swiotlb_dma_supported(struct device *hwdev, u64 mask)
+{
+ return xen_virt_to_bus(xen_io_tlb_end - 1) <= mask;
+}
+EXPORT_SYMBOL_GPL(xen_swiotlb_dma_supported);
diff --git a/drivers/xen/sys-hypervisor.c b/drivers/xen/sys-hypervisor.c
new file mode 100644
index 00000000..1e0fe01e
--- /dev/null
+++ b/drivers/xen/sys-hypervisor.c
@@ -0,0 +1,447 @@
+/*
+ * copyright (c) 2006 IBM Corporation
+ * Authored by: Mike D. Day <ncmike@us.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/slab.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/kobject.h>
+
+#include <asm/xen/hypervisor.h>
+#include <asm/xen/hypercall.h>
+
+#include <xen/xen.h>
+#include <xen/xenbus.h>
+#include <xen/interface/xen.h>
+#include <xen/interface/version.h>
+
+#define HYPERVISOR_ATTR_RO(_name) \
+static struct hyp_sysfs_attr _name##_attr = __ATTR_RO(_name)
+
+#define HYPERVISOR_ATTR_RW(_name) \
+static struct hyp_sysfs_attr _name##_attr = \
+ __ATTR(_name, 0644, _name##_show, _name##_store)
+
+struct hyp_sysfs_attr {
+ struct attribute attr;
+ ssize_t (*show)(struct hyp_sysfs_attr *, char *);
+ ssize_t (*store)(struct hyp_sysfs_attr *, const char *, size_t);
+ void *hyp_attr_data;
+};
+
+static ssize_t type_show(struct hyp_sysfs_attr *attr, char *buffer)
+{
+ return sprintf(buffer, "xen\n");
+}
+
+HYPERVISOR_ATTR_RO(type);
+
+static int __init xen_sysfs_type_init(void)
+{
+ return sysfs_create_file(hypervisor_kobj, &type_attr.attr);
+}
+
+static void xen_sysfs_type_destroy(void)
+{
+ sysfs_remove_file(hypervisor_kobj, &type_attr.attr);
+}
+
+/* xen version attributes */
+static ssize_t major_show(struct hyp_sysfs_attr *attr, char *buffer)
+{
+ int version = HYPERVISOR_xen_version(XENVER_version, NULL);
+ if (version)
+ return sprintf(buffer, "%d\n", version >> 16);
+ return -ENODEV;
+}
+
+HYPERVISOR_ATTR_RO(major);
+
+static ssize_t minor_show(struct hyp_sysfs_attr *attr, char *buffer)
+{
+ int version = HYPERVISOR_xen_version(XENVER_version, NULL);
+ if (version)
+ return sprintf(buffer, "%d\n", version & 0xff);
+ return -ENODEV;
+}
+
+HYPERVISOR_ATTR_RO(minor);
+
+static ssize_t extra_show(struct hyp_sysfs_attr *attr, char *buffer)
+{
+ int ret = -ENOMEM;
+ char *extra;
+
+ extra = kmalloc(XEN_EXTRAVERSION_LEN, GFP_KERNEL);
+ if (extra) {
+ ret = HYPERVISOR_xen_version(XENVER_extraversion, extra);
+ if (!ret)
+ ret = sprintf(buffer, "%s\n", extra);
+ kfree(extra);
+ }
+
+ return ret;
+}
+
+HYPERVISOR_ATTR_RO(extra);
+
+static struct attribute *version_attrs[] = {
+ &major_attr.attr,
+ &minor_attr.attr,
+ &extra_attr.attr,
+ NULL
+};
+
+static struct attribute_group version_group = {
+ .name = "version",
+ .attrs = version_attrs,
+};
+
+static int __init xen_sysfs_version_init(void)
+{
+ return sysfs_create_group(hypervisor_kobj, &version_group);
+}
+
+static void xen_sysfs_version_destroy(void)
+{
+ sysfs_remove_group(hypervisor_kobj, &version_group);
+}
+
+/* UUID */
+
+static ssize_t uuid_show(struct hyp_sysfs_attr *attr, char *buffer)
+{
+ char *vm, *val;
+ int ret;
+ extern int xenstored_ready;
+
+ if (!xenstored_ready)
+ return -EBUSY;
+
+ vm = xenbus_read(XBT_NIL, "vm", "", NULL);
+ if (IS_ERR(vm))
+ return PTR_ERR(vm);
+ val = xenbus_read(XBT_NIL, vm, "uuid", NULL);
+ kfree(vm);
+ if (IS_ERR(val))
+ return PTR_ERR(val);
+ ret = sprintf(buffer, "%s\n", val);
+ kfree(val);
+ return ret;
+}
+
+HYPERVISOR_ATTR_RO(uuid);
+
+static int __init xen_sysfs_uuid_init(void)
+{
+ return sysfs_create_file(hypervisor_kobj, &uuid_attr.attr);
+}
+
+static void xen_sysfs_uuid_destroy(void)
+{
+ sysfs_remove_file(hypervisor_kobj, &uuid_attr.attr);
+}
+
+/* xen compilation attributes */
+
+static ssize_t compiler_show(struct hyp_sysfs_attr *attr, char *buffer)
+{
+ int ret = -ENOMEM;
+ struct xen_compile_info *info;
+
+ info = kmalloc(sizeof(struct xen_compile_info), GFP_KERNEL);
+ if (info) {
+ ret = HYPERVISOR_xen_version(XENVER_compile_info, info);
+ if (!ret)
+ ret = sprintf(buffer, "%s\n", info->compiler);
+ kfree(info);
+ }
+
+ return ret;
+}
+
+HYPERVISOR_ATTR_RO(compiler);
+
+static ssize_t compiled_by_show(struct hyp_sysfs_attr *attr, char *buffer)
+{
+ int ret = -ENOMEM;
+ struct xen_compile_info *info;
+
+ info = kmalloc(sizeof(struct xen_compile_info), GFP_KERNEL);
+ if (info) {
+ ret = HYPERVISOR_xen_version(XENVER_compile_info, info);
+ if (!ret)
+ ret = sprintf(buffer, "%s\n", info->compile_by);
+ kfree(info);
+ }
+
+ return ret;
+}
+
+HYPERVISOR_ATTR_RO(compiled_by);
+
+static ssize_t compile_date_show(struct hyp_sysfs_attr *attr, char *buffer)
+{
+ int ret = -ENOMEM;
+ struct xen_compile_info *info;
+
+ info = kmalloc(sizeof(struct xen_compile_info), GFP_KERNEL);
+ if (info) {
+ ret = HYPERVISOR_xen_version(XENVER_compile_info, info);
+ if (!ret)
+ ret = sprintf(buffer, "%s\n", info->compile_date);
+ kfree(info);
+ }
+
+ return ret;
+}
+
+HYPERVISOR_ATTR_RO(compile_date);
+
+static struct attribute *xen_compile_attrs[] = {
+ &compiler_attr.attr,
+ &compiled_by_attr.attr,
+ &compile_date_attr.attr,
+ NULL
+};
+
+static struct attribute_group xen_compilation_group = {
+ .name = "compilation",
+ .attrs = xen_compile_attrs,
+};
+
+static int __init xen_compilation_init(void)
+{
+ return sysfs_create_group(hypervisor_kobj, &xen_compilation_group);
+}
+
+static void xen_compilation_destroy(void)
+{
+ sysfs_remove_group(hypervisor_kobj, &xen_compilation_group);
+}
+
+/* xen properties info */
+
+static ssize_t capabilities_show(struct hyp_sysfs_attr *attr, char *buffer)
+{
+ int ret = -ENOMEM;
+ char *caps;
+
+ caps = kmalloc(XEN_CAPABILITIES_INFO_LEN, GFP_KERNEL);
+ if (caps) {
+ ret = HYPERVISOR_xen_version(XENVER_capabilities, caps);
+ if (!ret)
+ ret = sprintf(buffer, "%s\n", caps);
+ kfree(caps);
+ }
+
+ return ret;
+}
+
+HYPERVISOR_ATTR_RO(capabilities);
+
+static ssize_t changeset_show(struct hyp_sysfs_attr *attr, char *buffer)
+{
+ int ret = -ENOMEM;
+ char *cset;
+
+ cset = kmalloc(XEN_CHANGESET_INFO_LEN, GFP_KERNEL);
+ if (cset) {
+ ret = HYPERVISOR_xen_version(XENVER_changeset, cset);
+ if (!ret)
+ ret = sprintf(buffer, "%s\n", cset);
+ kfree(cset);
+ }
+
+ return ret;
+}
+
+HYPERVISOR_ATTR_RO(changeset);
+
+static ssize_t virtual_start_show(struct hyp_sysfs_attr *attr, char *buffer)
+{
+ int ret = -ENOMEM;
+ struct xen_platform_parameters *parms;
+
+ parms = kmalloc(sizeof(struct xen_platform_parameters), GFP_KERNEL);
+ if (parms) {
+ ret = HYPERVISOR_xen_version(XENVER_platform_parameters,
+ parms);
+ if (!ret)
+ ret = sprintf(buffer, "%lx\n", parms->virt_start);
+ kfree(parms);
+ }
+
+ return ret;
+}
+
+HYPERVISOR_ATTR_RO(virtual_start);
+
+static ssize_t pagesize_show(struct hyp_sysfs_attr *attr, char *buffer)
+{
+ int ret;
+
+ ret = HYPERVISOR_xen_version(XENVER_pagesize, NULL);
+ if (ret > 0)
+ ret = sprintf(buffer, "%x\n", ret);
+
+ return ret;
+}
+
+HYPERVISOR_ATTR_RO(pagesize);
+
+static ssize_t xen_feature_show(int index, char *buffer)
+{
+ ssize_t ret;
+ struct xen_feature_info info;
+
+ info.submap_idx = index;
+ ret = HYPERVISOR_xen_version(XENVER_get_features, &info);
+ if (!ret)
+ ret = sprintf(buffer, "%08x", info.submap);
+
+ return ret;
+}
+
+static ssize_t features_show(struct hyp_sysfs_attr *attr, char *buffer)
+{
+ ssize_t len;
+ int i;
+
+ len = 0;
+ for (i = XENFEAT_NR_SUBMAPS-1; i >= 0; i--) {
+ int ret = xen_feature_show(i, buffer + len);
+ if (ret < 0) {
+ if (len == 0)
+ len = ret;
+ break;
+ }
+ len += ret;
+ }
+ if (len > 0)
+ buffer[len++] = '\n';
+
+ return len;
+}
+
+HYPERVISOR_ATTR_RO(features);
+
+static struct attribute *xen_properties_attrs[] = {
+ &capabilities_attr.attr,
+ &changeset_attr.attr,
+ &virtual_start_attr.attr,
+ &pagesize_attr.attr,
+ &features_attr.attr,
+ NULL
+};
+
+static struct attribute_group xen_properties_group = {
+ .name = "properties",
+ .attrs = xen_properties_attrs,
+};
+
+static int __init xen_properties_init(void)
+{
+ return sysfs_create_group(hypervisor_kobj, &xen_properties_group);
+}
+
+static void xen_properties_destroy(void)
+{
+ sysfs_remove_group(hypervisor_kobj, &xen_properties_group);
+}
+
+static int __init hyper_sysfs_init(void)
+{
+ int ret;
+
+ if (!xen_domain())
+ return -ENODEV;
+
+ ret = xen_sysfs_type_init();
+ if (ret)
+ goto out;
+ ret = xen_sysfs_version_init();
+ if (ret)
+ goto version_out;
+ ret = xen_compilation_init();
+ if (ret)
+ goto comp_out;
+ ret = xen_sysfs_uuid_init();
+ if (ret)
+ goto uuid_out;
+ ret = xen_properties_init();
+ if (ret)
+ goto prop_out;
+
+ goto out;
+
+prop_out:
+ xen_sysfs_uuid_destroy();
+uuid_out:
+ xen_compilation_destroy();
+comp_out:
+ xen_sysfs_version_destroy();
+version_out:
+ xen_sysfs_type_destroy();
+out:
+ return ret;
+}
+
+static void __exit hyper_sysfs_exit(void)
+{
+ xen_properties_destroy();
+ xen_compilation_destroy();
+ xen_sysfs_uuid_destroy();
+ xen_sysfs_version_destroy();
+ xen_sysfs_type_destroy();
+
+}
+module_init(hyper_sysfs_init);
+module_exit(hyper_sysfs_exit);
+
+static ssize_t hyp_sysfs_show(struct kobject *kobj,
+ struct attribute *attr,
+ char *buffer)
+{
+ struct hyp_sysfs_attr *hyp_attr;
+ hyp_attr = container_of(attr, struct hyp_sysfs_attr, attr);
+ if (hyp_attr->show)
+ return hyp_attr->show(hyp_attr, buffer);
+ return 0;
+}
+
+static ssize_t hyp_sysfs_store(struct kobject *kobj,
+ struct attribute *attr,
+ const char *buffer,
+ size_t len)
+{
+ struct hyp_sysfs_attr *hyp_attr;
+ hyp_attr = container_of(attr, struct hyp_sysfs_attr, attr);
+ if (hyp_attr->store)
+ return hyp_attr->store(hyp_attr, buffer, len);
+ return 0;
+}
+
+static const struct sysfs_ops hyp_sysfs_ops = {
+ .show = hyp_sysfs_show,
+ .store = hyp_sysfs_store,
+};
+
+static struct kobj_type hyp_sysfs_kobj_type = {
+ .sysfs_ops = &hyp_sysfs_ops,
+};
+
+static int __init hypervisor_subsys_init(void)
+{
+ if (!xen_domain())
+ return -ENODEV;
+
+ hypervisor_kobj->ktype = &hyp_sysfs_kobj_type;
+ return 0;
+}
+device_initcall(hypervisor_subsys_init);
diff --git a/drivers/xen/tmem.c b/drivers/xen/tmem.c
new file mode 100644
index 00000000..816a4495
--- /dev/null
+++ b/drivers/xen/tmem.c
@@ -0,0 +1,264 @@
+/*
+ * Xen implementation for transcendent memory (tmem)
+ *
+ * Copyright (C) 2009-2010 Oracle Corp. All rights reserved.
+ * Author: Dan Magenheimer
+ */
+
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/init.h>
+#include <linux/pagemap.h>
+#include <linux/cleancache.h>
+
+#include <xen/xen.h>
+#include <xen/interface/xen.h>
+#include <asm/xen/hypercall.h>
+#include <asm/xen/page.h>
+#include <asm/xen/hypervisor.h>
+
+#define TMEM_CONTROL 0
+#define TMEM_NEW_POOL 1
+#define TMEM_DESTROY_POOL 2
+#define TMEM_NEW_PAGE 3
+#define TMEM_PUT_PAGE 4
+#define TMEM_GET_PAGE 5
+#define TMEM_FLUSH_PAGE 6
+#define TMEM_FLUSH_OBJECT 7
+#define TMEM_READ 8
+#define TMEM_WRITE 9
+#define TMEM_XCHG 10
+
+/* Bits for HYPERVISOR_tmem_op(TMEM_NEW_POOL) */
+#define TMEM_POOL_PERSIST 1
+#define TMEM_POOL_SHARED 2
+#define TMEM_POOL_PAGESIZE_SHIFT 4
+#define TMEM_VERSION_SHIFT 24
+
+
+struct tmem_pool_uuid {
+ u64 uuid_lo;
+ u64 uuid_hi;
+};
+
+struct tmem_oid {
+ u64 oid[3];
+};
+
+#define TMEM_POOL_PRIVATE_UUID { 0, 0 }
+
+/* flags for tmem_ops.new_pool */
+#define TMEM_POOL_PERSIST 1
+#define TMEM_POOL_SHARED 2
+
+/* xen tmem foundation ops/hypercalls */
+
+static inline int xen_tmem_op(u32 tmem_cmd, u32 tmem_pool, struct tmem_oid oid,
+ u32 index, unsigned long gmfn, u32 tmem_offset, u32 pfn_offset, u32 len)
+{
+ struct tmem_op op;
+ int rc = 0;
+
+ op.cmd = tmem_cmd;
+ op.pool_id = tmem_pool;
+ op.u.gen.oid[0] = oid.oid[0];
+ op.u.gen.oid[1] = oid.oid[1];
+ op.u.gen.oid[2] = oid.oid[2];
+ op.u.gen.index = index;
+ op.u.gen.tmem_offset = tmem_offset;
+ op.u.gen.pfn_offset = pfn_offset;
+ op.u.gen.len = len;
+ set_xen_guest_handle(op.u.gen.gmfn, (void *)gmfn);
+ rc = HYPERVISOR_tmem_op(&op);
+ return rc;
+}
+
+static int xen_tmem_new_pool(struct tmem_pool_uuid uuid,
+ u32 flags, unsigned long pagesize)
+{
+ struct tmem_op op;
+ int rc = 0, pageshift;
+
+ for (pageshift = 0; pagesize != 1; pageshift++)
+ pagesize >>= 1;
+ flags |= (pageshift - 12) << TMEM_POOL_PAGESIZE_SHIFT;
+ flags |= TMEM_SPEC_VERSION << TMEM_VERSION_SHIFT;
+ op.cmd = TMEM_NEW_POOL;
+ op.u.new.uuid[0] = uuid.uuid_lo;
+ op.u.new.uuid[1] = uuid.uuid_hi;
+ op.u.new.flags = flags;
+ rc = HYPERVISOR_tmem_op(&op);
+ return rc;
+}
+
+/* xen generic tmem ops */
+
+static int xen_tmem_put_page(u32 pool_id, struct tmem_oid oid,
+ u32 index, unsigned long pfn)
+{
+ unsigned long gmfn = xen_pv_domain() ? pfn_to_mfn(pfn) : pfn;
+
+ return xen_tmem_op(TMEM_PUT_PAGE, pool_id, oid, index,
+ gmfn, 0, 0, 0);
+}
+
+static int xen_tmem_get_page(u32 pool_id, struct tmem_oid oid,
+ u32 index, unsigned long pfn)
+{
+ unsigned long gmfn = xen_pv_domain() ? pfn_to_mfn(pfn) : pfn;
+
+ return xen_tmem_op(TMEM_GET_PAGE, pool_id, oid, index,
+ gmfn, 0, 0, 0);
+}
+
+static int xen_tmem_flush_page(u32 pool_id, struct tmem_oid oid, u32 index)
+{
+ return xen_tmem_op(TMEM_FLUSH_PAGE, pool_id, oid, index,
+ 0, 0, 0, 0);
+}
+
+static int xen_tmem_flush_object(u32 pool_id, struct tmem_oid oid)
+{
+ return xen_tmem_op(TMEM_FLUSH_OBJECT, pool_id, oid, 0, 0, 0, 0, 0);
+}
+
+static int xen_tmem_destroy_pool(u32 pool_id)
+{
+ struct tmem_oid oid = { { 0 } };
+
+ return xen_tmem_op(TMEM_DESTROY_POOL, pool_id, oid, 0, 0, 0, 0, 0);
+}
+
+int tmem_enabled;
+
+static int __init enable_tmem(char *s)
+{
+ tmem_enabled = 1;
+ return 1;
+}
+
+__setup("tmem", enable_tmem);
+
+/* cleancache ops */
+
+static void tmem_cleancache_put_page(int pool, struct cleancache_filekey key,
+ pgoff_t index, struct page *page)
+{
+ u32 ind = (u32) index;
+ struct tmem_oid oid = *(struct tmem_oid *)&key;
+ unsigned long pfn = page_to_pfn(page);
+
+ if (pool < 0)
+ return;
+ if (ind != index)
+ return;
+ mb(); /* ensure page is quiescent; tmem may address it with an alias */
+ (void)xen_tmem_put_page((u32)pool, oid, ind, pfn);
+}
+
+static int tmem_cleancache_get_page(int pool, struct cleancache_filekey key,
+ pgoff_t index, struct page *page)
+{
+ u32 ind = (u32) index;
+ struct tmem_oid oid = *(struct tmem_oid *)&key;
+ unsigned long pfn = page_to_pfn(page);
+ int ret;
+
+ /* translate return values to linux semantics */
+ if (pool < 0)
+ return -1;
+ if (ind != index)
+ return -1;
+ ret = xen_tmem_get_page((u32)pool, oid, ind, pfn);
+ if (ret == 1)
+ return 0;
+ else
+ return -1;
+}
+
+static void tmem_cleancache_flush_page(int pool, struct cleancache_filekey key,
+ pgoff_t index)
+{
+ u32 ind = (u32) index;
+ struct tmem_oid oid = *(struct tmem_oid *)&key;
+
+ if (pool < 0)
+ return;
+ if (ind != index)
+ return;
+ (void)xen_tmem_flush_page((u32)pool, oid, ind);
+}
+
+static void tmem_cleancache_flush_inode(int pool, struct cleancache_filekey key)
+{
+ struct tmem_oid oid = *(struct tmem_oid *)&key;
+
+ if (pool < 0)
+ return;
+ (void)xen_tmem_flush_object((u32)pool, oid);
+}
+
+static void tmem_cleancache_flush_fs(int pool)
+{
+ if (pool < 0)
+ return;
+ (void)xen_tmem_destroy_pool((u32)pool);
+}
+
+static int tmem_cleancache_init_fs(size_t pagesize)
+{
+ struct tmem_pool_uuid uuid_private = TMEM_POOL_PRIVATE_UUID;
+
+ return xen_tmem_new_pool(uuid_private, 0, pagesize);
+}
+
+static int tmem_cleancache_init_shared_fs(char *uuid, size_t pagesize)
+{
+ struct tmem_pool_uuid shared_uuid;
+
+ shared_uuid.uuid_lo = *(u64 *)uuid;
+ shared_uuid.uuid_hi = *(u64 *)(&uuid[8]);
+ return xen_tmem_new_pool(shared_uuid, TMEM_POOL_SHARED, pagesize);
+}
+
+static int use_cleancache = 1;
+
+static int __init no_cleancache(char *s)
+{
+ use_cleancache = 0;
+ return 1;
+}
+
+__setup("nocleancache", no_cleancache);
+
+static struct cleancache_ops tmem_cleancache_ops = {
+ .put_page = tmem_cleancache_put_page,
+ .get_page = tmem_cleancache_get_page,
+ .flush_page = tmem_cleancache_flush_page,
+ .flush_inode = tmem_cleancache_flush_inode,
+ .flush_fs = tmem_cleancache_flush_fs,
+ .init_shared_fs = tmem_cleancache_init_shared_fs,
+ .init_fs = tmem_cleancache_init_fs
+};
+
+static int __init xen_tmem_init(void)
+{
+ struct cleancache_ops old_ops;
+
+ if (!xen_domain())
+ return 0;
+#ifdef CONFIG_CLEANCACHE
+ BUG_ON(sizeof(struct cleancache_filekey) != sizeof(struct tmem_oid));
+ if (tmem_enabled && use_cleancache) {
+ char *s = "";
+ old_ops = cleancache_register_ops(&tmem_cleancache_ops);
+ if (old_ops.init_fs != NULL)
+ s = " (WARNING: cleancache_ops overridden)";
+ printk(KERN_INFO "cleancache enabled, RAM provided by "
+ "Xen Transcendent Memory%s\n", s);
+ }
+#endif
+ return 0;
+}
+
+module_init(xen_tmem_init)
diff --git a/drivers/xen/xen-balloon.c b/drivers/xen/xen-balloon.c
new file mode 100644
index 00000000..a4ff225e
--- /dev/null
+++ b/drivers/xen/xen-balloon.c
@@ -0,0 +1,256 @@
+/******************************************************************************
+ * Xen balloon driver - enables returning/claiming memory to/from Xen.
+ *
+ * Copyright (c) 2003, B Dragovic
+ * Copyright (c) 2003-2004, M Williamson, K Fraser
+ * Copyright (c) 2005 Dan M. Smith, IBM Corporation
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation; or, when distributed
+ * separately from the Linux kernel or incorporated into other
+ * software packages, subject to the following license:
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this source file (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use, copy, modify,
+ * merge, publish, distribute, sublicense, and/or sell copies of the Software,
+ * and to permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/sysdev.h>
+#include <linux/capability.h>
+
+#include <xen/xen.h>
+#include <xen/interface/xen.h>
+#include <xen/balloon.h>
+#include <xen/xenbus.h>
+#include <xen/features.h>
+#include <xen/page.h>
+
+#define PAGES2KB(_p) ((_p)<<(PAGE_SHIFT-10))
+
+#define BALLOON_CLASS_NAME "xen_memory"
+
+static struct sys_device balloon_sysdev;
+
+static int register_balloon(struct sys_device *sysdev);
+
+static struct xenbus_watch target_watch =
+{
+ .node = "memory/target"
+};
+
+/* React to a change in the target key */
+static void watch_target(struct xenbus_watch *watch,
+ const char **vec, unsigned int len)
+{
+ unsigned long long new_target;
+ int err;
+
+ err = xenbus_scanf(XBT_NIL, "memory", "target", "%llu", &new_target);
+ if (err != 1) {
+ /* This is ok (for domain0 at least) - so just return */
+ return;
+ }
+
+ /* The given memory/target value is in KiB, so it needs converting to
+ * pages. PAGE_SHIFT converts bytes to pages, hence PAGE_SHIFT - 10.
+ */
+ balloon_set_new_target(new_target >> (PAGE_SHIFT - 10));
+}
+
+static int balloon_init_watcher(struct notifier_block *notifier,
+ unsigned long event,
+ void *data)
+{
+ int err;
+
+ err = register_xenbus_watch(&target_watch);
+ if (err)
+ printk(KERN_ERR "Failed to set balloon watcher\n");
+
+ return NOTIFY_DONE;
+}
+
+static struct notifier_block xenstore_notifier;
+
+static int __init balloon_init(void)
+{
+ if (!xen_domain())
+ return -ENODEV;
+
+ pr_info("xen-balloon: Initialising balloon driver.\n");
+
+ register_balloon(&balloon_sysdev);
+
+ target_watch.callback = watch_target;
+ xenstore_notifier.notifier_call = balloon_init_watcher;
+
+ register_xenstore_notifier(&xenstore_notifier);
+
+ return 0;
+}
+subsys_initcall(balloon_init);
+
+static void balloon_exit(void)
+{
+ /* XXX - release balloon here */
+ return;
+}
+
+module_exit(balloon_exit);
+
+#define BALLOON_SHOW(name, format, args...) \
+ static ssize_t show_##name(struct sys_device *dev, \
+ struct sysdev_attribute *attr, \
+ char *buf) \
+ { \
+ return sprintf(buf, format, ##args); \
+ } \
+ static SYSDEV_ATTR(name, S_IRUGO, show_##name, NULL)
+
+BALLOON_SHOW(current_kb, "%lu\n", PAGES2KB(balloon_stats.current_pages));
+BALLOON_SHOW(low_kb, "%lu\n", PAGES2KB(balloon_stats.balloon_low));
+BALLOON_SHOW(high_kb, "%lu\n", PAGES2KB(balloon_stats.balloon_high));
+
+static SYSDEV_ULONG_ATTR(schedule_delay, 0444, balloon_stats.schedule_delay);
+static SYSDEV_ULONG_ATTR(max_schedule_delay, 0644, balloon_stats.max_schedule_delay);
+static SYSDEV_ULONG_ATTR(retry_count, 0444, balloon_stats.retry_count);
+static SYSDEV_ULONG_ATTR(max_retry_count, 0644, balloon_stats.max_retry_count);
+
+static ssize_t show_target_kb(struct sys_device *dev, struct sysdev_attribute *attr,
+ char *buf)
+{
+ return sprintf(buf, "%lu\n", PAGES2KB(balloon_stats.target_pages));
+}
+
+static ssize_t store_target_kb(struct sys_device *dev,
+ struct sysdev_attribute *attr,
+ const char *buf,
+ size_t count)
+{
+ char *endchar;
+ unsigned long long target_bytes;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ target_bytes = simple_strtoull(buf, &endchar, 0) * 1024;
+
+ balloon_set_new_target(target_bytes >> PAGE_SHIFT);
+
+ return count;
+}
+
+static SYSDEV_ATTR(target_kb, S_IRUGO | S_IWUSR,
+ show_target_kb, store_target_kb);
+
+
+static ssize_t show_target(struct sys_device *dev, struct sysdev_attribute *attr,
+ char *buf)
+{
+ return sprintf(buf, "%llu\n",
+ (unsigned long long)balloon_stats.target_pages
+ << PAGE_SHIFT);
+}
+
+static ssize_t store_target(struct sys_device *dev,
+ struct sysdev_attribute *attr,
+ const char *buf,
+ size_t count)
+{
+ char *endchar;
+ unsigned long long target_bytes;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ target_bytes = memparse(buf, &endchar);
+
+ balloon_set_new_target(target_bytes >> PAGE_SHIFT);
+
+ return count;
+}
+
+static SYSDEV_ATTR(target, S_IRUGO | S_IWUSR,
+ show_target, store_target);
+
+
+static struct sysdev_attribute *balloon_attrs[] = {
+ &attr_target_kb,
+ &attr_target,
+ &attr_schedule_delay.attr,
+ &attr_max_schedule_delay.attr,
+ &attr_retry_count.attr,
+ &attr_max_retry_count.attr
+};
+
+static struct attribute *balloon_info_attrs[] = {
+ &attr_current_kb.attr,
+ &attr_low_kb.attr,
+ &attr_high_kb.attr,
+ NULL
+};
+
+static struct attribute_group balloon_info_group = {
+ .name = "info",
+ .attrs = balloon_info_attrs
+};
+
+static struct sysdev_class balloon_sysdev_class = {
+ .name = BALLOON_CLASS_NAME
+};
+
+static int register_balloon(struct sys_device *sysdev)
+{
+ int i, error;
+
+ error = sysdev_class_register(&balloon_sysdev_class);
+ if (error)
+ return error;
+
+ sysdev->id = 0;
+ sysdev->cls = &balloon_sysdev_class;
+
+ error = sysdev_register(sysdev);
+ if (error) {
+ sysdev_class_unregister(&balloon_sysdev_class);
+ return error;
+ }
+
+ for (i = 0; i < ARRAY_SIZE(balloon_attrs); i++) {
+ error = sysdev_create_file(sysdev, balloon_attrs[i]);
+ if (error)
+ goto fail;
+ }
+
+ error = sysfs_create_group(&sysdev->kobj, &balloon_info_group);
+ if (error)
+ goto fail;
+
+ return 0;
+
+ fail:
+ while (--i >= 0)
+ sysdev_remove_file(sysdev, balloon_attrs[i]);
+ sysdev_unregister(sysdev);
+ sysdev_class_unregister(&balloon_sysdev_class);
+ return error;
+}
+
+MODULE_LICENSE("GPL");
diff --git a/drivers/xen/xenbus/Makefile b/drivers/xen/xenbus/Makefile
new file mode 100644
index 00000000..8dca6853
--- /dev/null
+++ b/drivers/xen/xenbus/Makefile
@@ -0,0 +1,12 @@
+obj-y += xenbus.o
+
+xenbus-objs =
+xenbus-objs += xenbus_client.o
+xenbus-objs += xenbus_comms.o
+xenbus-objs += xenbus_xs.o
+xenbus-objs += xenbus_probe.o
+
+xenbus-be-objs-$(CONFIG_XEN_BACKEND) += xenbus_probe_backend.o
+xenbus-objs += $(xenbus-be-objs-y)
+
+obj-$(CONFIG_XEN_XENBUS_FRONTEND) += xenbus_probe_frontend.o
diff --git a/drivers/xen/xenbus/xenbus_client.c b/drivers/xen/xenbus/xenbus_client.c
new file mode 100644
index 00000000..cdacf923
--- /dev/null
+++ b/drivers/xen/xenbus/xenbus_client.c
@@ -0,0 +1,613 @@
+/******************************************************************************
+ * Client-facing interface for the Xenbus driver. In other words, the
+ * interface between the Xenbus and the device-specific code, be it the
+ * frontend or the backend of that driver.
+ *
+ * Copyright (C) 2005 XenSource Ltd
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation; or, when distributed
+ * separately from the Linux kernel or incorporated into other
+ * software packages, subject to the following license:
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this source file (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use, copy, modify,
+ * merge, publish, distribute, sublicense, and/or sell copies of the Software,
+ * and to permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#include <linux/slab.h>
+#include <linux/types.h>
+#include <linux/vmalloc.h>
+#include <asm/xen/hypervisor.h>
+#include <xen/interface/xen.h>
+#include <xen/interface/event_channel.h>
+#include <xen/events.h>
+#include <xen/grant_table.h>
+#include <xen/xenbus.h>
+
+const char *xenbus_strstate(enum xenbus_state state)
+{
+ static const char *const name[] = {
+ [ XenbusStateUnknown ] = "Unknown",
+ [ XenbusStateInitialising ] = "Initialising",
+ [ XenbusStateInitWait ] = "InitWait",
+ [ XenbusStateInitialised ] = "Initialised",
+ [ XenbusStateConnected ] = "Connected",
+ [ XenbusStateClosing ] = "Closing",
+ [ XenbusStateClosed ] = "Closed",
+ [XenbusStateReconfiguring] = "Reconfiguring",
+ [XenbusStateReconfigured] = "Reconfigured",
+ };
+ return (state < ARRAY_SIZE(name)) ? name[state] : "INVALID";
+}
+EXPORT_SYMBOL_GPL(xenbus_strstate);
+
+/**
+ * xenbus_watch_path - register a watch
+ * @dev: xenbus device
+ * @path: path to watch
+ * @watch: watch to register
+ * @callback: callback to register
+ *
+ * Register a @watch on the given path, using the given xenbus_watch structure
+ * for storage, and the given @callback function as the callback. Return 0 on
+ * success, or -errno on error. On success, the given @path will be saved as
+ * @watch->node, and remains the caller's to free. On error, @watch->node will
+ * be NULL, the device will switch to %XenbusStateClosing, and the error will
+ * be saved in the store.
+ */
+int xenbus_watch_path(struct xenbus_device *dev, const char *path,
+ struct xenbus_watch *watch,
+ void (*callback)(struct xenbus_watch *,
+ const char **, unsigned int))
+{
+ int err;
+
+ watch->node = path;
+ watch->callback = callback;
+
+ err = register_xenbus_watch(watch);
+
+ if (err) {
+ watch->node = NULL;
+ watch->callback = NULL;
+ xenbus_dev_fatal(dev, err, "adding watch on %s", path);
+ }
+
+ return err;
+}
+EXPORT_SYMBOL_GPL(xenbus_watch_path);
+
+
+/**
+ * xenbus_watch_pathfmt - register a watch on a sprintf-formatted path
+ * @dev: xenbus device
+ * @watch: watch to register
+ * @callback: callback to register
+ * @pathfmt: format of path to watch
+ *
+ * Register a watch on the given @path, using the given xenbus_watch
+ * structure for storage, and the given @callback function as the callback.
+ * Return 0 on success, or -errno on error. On success, the watched path
+ * (@path/@path2) will be saved as @watch->node, and becomes the caller's to
+ * kfree(). On error, watch->node will be NULL, so the caller has nothing to
+ * free, the device will switch to %XenbusStateClosing, and the error will be
+ * saved in the store.
+ */
+int xenbus_watch_pathfmt(struct xenbus_device *dev,
+ struct xenbus_watch *watch,
+ void (*callback)(struct xenbus_watch *,
+ const char **, unsigned int),
+ const char *pathfmt, ...)
+{
+ int err;
+ va_list ap;
+ char *path;
+
+ va_start(ap, pathfmt);
+ path = kvasprintf(GFP_NOIO | __GFP_HIGH, pathfmt, ap);
+ va_end(ap);
+
+ if (!path) {
+ xenbus_dev_fatal(dev, -ENOMEM, "allocating path for watch");
+ return -ENOMEM;
+ }
+ err = xenbus_watch_path(dev, path, watch, callback);
+
+ if (err)
+ kfree(path);
+ return err;
+}
+EXPORT_SYMBOL_GPL(xenbus_watch_pathfmt);
+
+static void xenbus_switch_fatal(struct xenbus_device *, int, int,
+ const char *, ...);
+
+static int
+__xenbus_switch_state(struct xenbus_device *dev,
+ enum xenbus_state state, int depth)
+{
+ /* We check whether the state is currently set to the given value, and
+ if not, then the state is set. We don't want to unconditionally
+ write the given state, because we don't want to fire watches
+ unnecessarily. Furthermore, if the node has gone, we don't write
+ to it, as the device will be tearing down, and we don't want to
+ resurrect that directory.
+
+ Note that, because of this cached value of our state, this
+ function will not take a caller's Xenstore transaction
+ (something it was trying to in the past) because dev->state
+ would not get reset if the transaction was aborted.
+ */
+
+ struct xenbus_transaction xbt;
+ int current_state;
+ int err, abort;
+
+ if (state == dev->state)
+ return 0;
+
+again:
+ abort = 1;
+
+ err = xenbus_transaction_start(&xbt);
+ if (err) {
+ xenbus_switch_fatal(dev, depth, err, "starting transaction");
+ return 0;
+ }
+
+ err = xenbus_scanf(xbt, dev->nodename, "state", "%d", &current_state);
+ if (err != 1)
+ goto abort;
+
+ err = xenbus_printf(xbt, dev->nodename, "state", "%d", state);
+ if (err) {
+ xenbus_switch_fatal(dev, depth, err, "writing new state");
+ goto abort;
+ }
+
+ abort = 0;
+abort:
+ err = xenbus_transaction_end(xbt, abort);
+ if (err) {
+ if (err == -EAGAIN && !abort)
+ goto again;
+ xenbus_switch_fatal(dev, depth, err, "ending transaction");
+ } else
+ dev->state = state;
+
+ return 0;
+}
+
+/**
+ * xenbus_switch_state
+ * @dev: xenbus device
+ * @state: new state
+ *
+ * Advertise in the store a change of the given driver to the given new_state.
+ * Return 0 on success, or -errno on error. On error, the device will switch
+ * to XenbusStateClosing, and the error will be saved in the store.
+ */
+int xenbus_switch_state(struct xenbus_device *dev, enum xenbus_state state)
+{
+ return __xenbus_switch_state(dev, state, 0);
+}
+
+EXPORT_SYMBOL_GPL(xenbus_switch_state);
+
+int xenbus_frontend_closed(struct xenbus_device *dev)
+{
+ xenbus_switch_state(dev, XenbusStateClosed);
+ complete(&dev->down);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(xenbus_frontend_closed);
+
+/**
+ * Return the path to the error node for the given device, or NULL on failure.
+ * If the value returned is non-NULL, then it is the caller's to kfree.
+ */
+static char *error_path(struct xenbus_device *dev)
+{
+ return kasprintf(GFP_KERNEL, "error/%s", dev->nodename);
+}
+
+
+static void xenbus_va_dev_error(struct xenbus_device *dev, int err,
+ const char *fmt, va_list ap)
+{
+ int ret;
+ unsigned int len;
+ char *printf_buffer = NULL;
+ char *path_buffer = NULL;
+
+#define PRINTF_BUFFER_SIZE 4096
+ printf_buffer = kmalloc(PRINTF_BUFFER_SIZE, GFP_KERNEL);
+ if (printf_buffer == NULL)
+ goto fail;
+
+ len = sprintf(printf_buffer, "%i ", -err);
+ ret = vsnprintf(printf_buffer+len, PRINTF_BUFFER_SIZE-len, fmt, ap);
+
+ BUG_ON(len + ret > PRINTF_BUFFER_SIZE-1);
+
+ dev_err(&dev->dev, "%s\n", printf_buffer);
+
+ path_buffer = error_path(dev);
+
+ if (path_buffer == NULL) {
+ dev_err(&dev->dev, "failed to write error node for %s (%s)\n",
+ dev->nodename, printf_buffer);
+ goto fail;
+ }
+
+ if (xenbus_write(XBT_NIL, path_buffer, "error", printf_buffer) != 0) {
+ dev_err(&dev->dev, "failed to write error node for %s (%s)\n",
+ dev->nodename, printf_buffer);
+ goto fail;
+ }
+
+fail:
+ kfree(printf_buffer);
+ kfree(path_buffer);
+}
+
+
+/**
+ * xenbus_dev_error
+ * @dev: xenbus device
+ * @err: error to report
+ * @fmt: error message format
+ *
+ * Report the given negative errno into the store, along with the given
+ * formatted message.
+ */
+void xenbus_dev_error(struct xenbus_device *dev, int err, const char *fmt, ...)
+{
+ va_list ap;
+
+ va_start(ap, fmt);
+ xenbus_va_dev_error(dev, err, fmt, ap);
+ va_end(ap);
+}
+EXPORT_SYMBOL_GPL(xenbus_dev_error);
+
+/**
+ * xenbus_dev_fatal
+ * @dev: xenbus device
+ * @err: error to report
+ * @fmt: error message format
+ *
+ * Equivalent to xenbus_dev_error(dev, err, fmt, args), followed by
+ * xenbus_switch_state(dev, XenbusStateClosing) to schedule an orderly
+ * closedown of this driver and its peer.
+ */
+
+void xenbus_dev_fatal(struct xenbus_device *dev, int err, const char *fmt, ...)
+{
+ va_list ap;
+
+ va_start(ap, fmt);
+ xenbus_va_dev_error(dev, err, fmt, ap);
+ va_end(ap);
+
+ xenbus_switch_state(dev, XenbusStateClosing);
+}
+EXPORT_SYMBOL_GPL(xenbus_dev_fatal);
+
+/**
+ * Equivalent to xenbus_dev_fatal(dev, err, fmt, args), but helps
+ * avoiding recursion within xenbus_switch_state.
+ */
+static void xenbus_switch_fatal(struct xenbus_device *dev, int depth, int err,
+ const char *fmt, ...)
+{
+ va_list ap;
+
+ va_start(ap, fmt);
+ xenbus_va_dev_error(dev, err, fmt, ap);
+ va_end(ap);
+
+ if (!depth)
+ __xenbus_switch_state(dev, XenbusStateClosing, 1);
+}
+
+/**
+ * xenbus_grant_ring
+ * @dev: xenbus device
+ * @ring_mfn: mfn of ring to grant
+
+ * Grant access to the given @ring_mfn to the peer of the given device. Return
+ * 0 on success, or -errno on error. On error, the device will switch to
+ * XenbusStateClosing, and the error will be saved in the store.
+ */
+int xenbus_grant_ring(struct xenbus_device *dev, unsigned long ring_mfn)
+{
+ int err = gnttab_grant_foreign_access(dev->otherend_id, ring_mfn, 0);
+ if (err < 0)
+ xenbus_dev_fatal(dev, err, "granting access to ring page");
+ return err;
+}
+EXPORT_SYMBOL_GPL(xenbus_grant_ring);
+
+
+/**
+ * Allocate an event channel for the given xenbus_device, assigning the newly
+ * created local port to *port. Return 0 on success, or -errno on error. On
+ * error, the device will switch to XenbusStateClosing, and the error will be
+ * saved in the store.
+ */
+int xenbus_alloc_evtchn(struct xenbus_device *dev, int *port)
+{
+ struct evtchn_alloc_unbound alloc_unbound;
+ int err;
+
+ alloc_unbound.dom = DOMID_SELF;
+ alloc_unbound.remote_dom = dev->otherend_id;
+
+ err = HYPERVISOR_event_channel_op(EVTCHNOP_alloc_unbound,
+ &alloc_unbound);
+ if (err)
+ xenbus_dev_fatal(dev, err, "allocating event channel");
+ else
+ *port = alloc_unbound.port;
+
+ return err;
+}
+EXPORT_SYMBOL_GPL(xenbus_alloc_evtchn);
+
+
+/**
+ * Bind to an existing interdomain event channel in another domain. Returns 0
+ * on success and stores the local port in *port. On error, returns -errno,
+ * switches the device to XenbusStateClosing, and saves the error in XenStore.
+ */
+int xenbus_bind_evtchn(struct xenbus_device *dev, int remote_port, int *port)
+{
+ struct evtchn_bind_interdomain bind_interdomain;
+ int err;
+
+ bind_interdomain.remote_dom = dev->otherend_id;
+ bind_interdomain.remote_port = remote_port;
+
+ err = HYPERVISOR_event_channel_op(EVTCHNOP_bind_interdomain,
+ &bind_interdomain);
+ if (err)
+ xenbus_dev_fatal(dev, err,
+ "binding to event channel %d from domain %d",
+ remote_port, dev->otherend_id);
+ else
+ *port = bind_interdomain.local_port;
+
+ return err;
+}
+EXPORT_SYMBOL_GPL(xenbus_bind_evtchn);
+
+
+/**
+ * Free an existing event channel. Returns 0 on success or -errno on error.
+ */
+int xenbus_free_evtchn(struct xenbus_device *dev, int port)
+{
+ struct evtchn_close close;
+ int err;
+
+ close.port = port;
+
+ err = HYPERVISOR_event_channel_op(EVTCHNOP_close, &close);
+ if (err)
+ xenbus_dev_error(dev, err, "freeing event channel %d", port);
+
+ return err;
+}
+EXPORT_SYMBOL_GPL(xenbus_free_evtchn);
+
+
+/**
+ * xenbus_map_ring_valloc
+ * @dev: xenbus device
+ * @gnt_ref: grant reference
+ * @vaddr: pointer to address to be filled out by mapping
+ *
+ * Based on Rusty Russell's skeleton driver's map_page.
+ * Map a page of memory into this domain from another domain's grant table.
+ * xenbus_map_ring_valloc allocates a page of virtual address space, maps the
+ * page to that address, and sets *vaddr to that address.
+ * Returns 0 on success, and GNTST_* (see xen/include/interface/grant_table.h)
+ * or -ENOMEM on error. If an error is returned, device will switch to
+ * XenbusStateClosing and the error message will be saved in XenStore.
+ */
+int xenbus_map_ring_valloc(struct xenbus_device *dev, int gnt_ref, void **vaddr)
+{
+ struct gnttab_map_grant_ref op = {
+ .flags = GNTMAP_host_map,
+ .ref = gnt_ref,
+ .dom = dev->otherend_id,
+ };
+ struct vm_struct *area;
+
+ *vaddr = NULL;
+
+ area = xen_alloc_vm_area(PAGE_SIZE);
+ if (!area)
+ return -ENOMEM;
+
+ op.host_addr = (unsigned long)area->addr;
+
+ if (HYPERVISOR_grant_table_op(GNTTABOP_map_grant_ref, &op, 1))
+ BUG();
+
+ if (op.status != GNTST_okay) {
+ xen_free_vm_area(area);
+ xenbus_dev_fatal(dev, op.status,
+ "mapping in shared page %d from domain %d",
+ gnt_ref, dev->otherend_id);
+ return op.status;
+ }
+
+ /* Stuff the handle in an unused field */
+ area->phys_addr = (unsigned long)op.handle;
+
+ *vaddr = area->addr;
+ return 0;
+}
+EXPORT_SYMBOL_GPL(xenbus_map_ring_valloc);
+
+
+/**
+ * xenbus_map_ring
+ * @dev: xenbus device
+ * @gnt_ref: grant reference
+ * @handle: pointer to grant handle to be filled
+ * @vaddr: address to be mapped to
+ *
+ * Map a page of memory into this domain from another domain's grant table.
+ * xenbus_map_ring does not allocate the virtual address space (you must do
+ * this yourself!). It only maps in the page to the specified address.
+ * Returns 0 on success, and GNTST_* (see xen/include/interface/grant_table.h)
+ * or -ENOMEM on error. If an error is returned, device will switch to
+ * XenbusStateClosing and the error message will be saved in XenStore.
+ */
+int xenbus_map_ring(struct xenbus_device *dev, int gnt_ref,
+ grant_handle_t *handle, void *vaddr)
+{
+ struct gnttab_map_grant_ref op = {
+ .host_addr = (unsigned long)vaddr,
+ .flags = GNTMAP_host_map,
+ .ref = gnt_ref,
+ .dom = dev->otherend_id,
+ };
+
+ if (HYPERVISOR_grant_table_op(GNTTABOP_map_grant_ref, &op, 1))
+ BUG();
+
+ if (op.status != GNTST_okay) {
+ xenbus_dev_fatal(dev, op.status,
+ "mapping in shared page %d from domain %d",
+ gnt_ref, dev->otherend_id);
+ } else
+ *handle = op.handle;
+
+ return op.status;
+}
+EXPORT_SYMBOL_GPL(xenbus_map_ring);
+
+
+/**
+ * xenbus_unmap_ring_vfree
+ * @dev: xenbus device
+ * @vaddr: addr to unmap
+ *
+ * Based on Rusty Russell's skeleton driver's unmap_page.
+ * Unmap a page of memory in this domain that was imported from another domain.
+ * Use xenbus_unmap_ring_vfree if you mapped in your memory with
+ * xenbus_map_ring_valloc (it will free the virtual address space).
+ * Returns 0 on success and returns GNTST_* on error
+ * (see xen/include/interface/grant_table.h).
+ */
+int xenbus_unmap_ring_vfree(struct xenbus_device *dev, void *vaddr)
+{
+ struct vm_struct *area;
+ struct gnttab_unmap_grant_ref op = {
+ .host_addr = (unsigned long)vaddr,
+ };
+
+ /* It'd be nice if linux/vmalloc.h provided a find_vm_area(void *addr)
+ * method so that we don't have to muck with vmalloc internals here.
+ * We could force the user to hang on to their struct vm_struct from
+ * xenbus_map_ring_valloc, but these 6 lines considerably simplify
+ * this API.
+ */
+ read_lock(&vmlist_lock);
+ for (area = vmlist; area != NULL; area = area->next) {
+ if (area->addr == vaddr)
+ break;
+ }
+ read_unlock(&vmlist_lock);
+
+ if (!area) {
+ xenbus_dev_error(dev, -ENOENT,
+ "can't find mapped virtual address %p", vaddr);
+ return GNTST_bad_virt_addr;
+ }
+
+ op.handle = (grant_handle_t)area->phys_addr;
+
+ if (HYPERVISOR_grant_table_op(GNTTABOP_unmap_grant_ref, &op, 1))
+ BUG();
+
+ if (op.status == GNTST_okay)
+ xen_free_vm_area(area);
+ else
+ xenbus_dev_error(dev, op.status,
+ "unmapping page at handle %d error %d",
+ (int16_t)area->phys_addr, op.status);
+
+ return op.status;
+}
+EXPORT_SYMBOL_GPL(xenbus_unmap_ring_vfree);
+
+
+/**
+ * xenbus_unmap_ring
+ * @dev: xenbus device
+ * @handle: grant handle
+ * @vaddr: addr to unmap
+ *
+ * Unmap a page of memory in this domain that was imported from another domain.
+ * Returns 0 on success and returns GNTST_* on error
+ * (see xen/include/interface/grant_table.h).
+ */
+int xenbus_unmap_ring(struct xenbus_device *dev,
+ grant_handle_t handle, void *vaddr)
+{
+ struct gnttab_unmap_grant_ref op = {
+ .host_addr = (unsigned long)vaddr,
+ .handle = handle,
+ };
+
+ if (HYPERVISOR_grant_table_op(GNTTABOP_unmap_grant_ref, &op, 1))
+ BUG();
+
+ if (op.status != GNTST_okay)
+ xenbus_dev_error(dev, op.status,
+ "unmapping page at handle %d error %d",
+ handle, op.status);
+
+ return op.status;
+}
+EXPORT_SYMBOL_GPL(xenbus_unmap_ring);
+
+
+/**
+ * xenbus_read_driver_state
+ * @path: path for driver
+ *
+ * Return the state of the driver rooted at the given store path, or
+ * XenbusStateUnknown if no state can be read.
+ */
+enum xenbus_state xenbus_read_driver_state(const char *path)
+{
+ enum xenbus_state result;
+ int err = xenbus_gather(XBT_NIL, path, "state", "%d", &result, NULL);
+ if (err)
+ result = XenbusStateUnknown;
+
+ return result;
+}
+EXPORT_SYMBOL_GPL(xenbus_read_driver_state);
diff --git a/drivers/xen/xenbus/xenbus_comms.c b/drivers/xen/xenbus/xenbus_comms.c
new file mode 100644
index 00000000..090c61ee
--- /dev/null
+++ b/drivers/xen/xenbus/xenbus_comms.c
@@ -0,0 +1,234 @@
+/******************************************************************************
+ * xenbus_comms.c
+ *
+ * Low level code to talks to Xen Store: ringbuffer and event channel.
+ *
+ * Copyright (C) 2005 Rusty Russell, IBM Corporation
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation; or, when distributed
+ * separately from the Linux kernel or incorporated into other
+ * software packages, subject to the following license:
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this source file (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use, copy, modify,
+ * merge, publish, distribute, sublicense, and/or sell copies of the Software,
+ * and to permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#include <linux/wait.h>
+#include <linux/interrupt.h>
+#include <linux/sched.h>
+#include <linux/err.h>
+#include <xen/xenbus.h>
+#include <asm/xen/hypervisor.h>
+#include <xen/events.h>
+#include <xen/page.h>
+#include "xenbus_comms.h"
+
+static int xenbus_irq;
+
+static DECLARE_WORK(probe_work, xenbus_probe);
+
+static DECLARE_WAIT_QUEUE_HEAD(xb_waitq);
+
+static irqreturn_t wake_waiting(int irq, void *unused)
+{
+ if (unlikely(xenstored_ready == 0)) {
+ xenstored_ready = 1;
+ schedule_work(&probe_work);
+ }
+
+ wake_up(&xb_waitq);
+ return IRQ_HANDLED;
+}
+
+static int check_indexes(XENSTORE_RING_IDX cons, XENSTORE_RING_IDX prod)
+{
+ return ((prod - cons) <= XENSTORE_RING_SIZE);
+}
+
+static void *get_output_chunk(XENSTORE_RING_IDX cons,
+ XENSTORE_RING_IDX prod,
+ char *buf, uint32_t *len)
+{
+ *len = XENSTORE_RING_SIZE - MASK_XENSTORE_IDX(prod);
+ if ((XENSTORE_RING_SIZE - (prod - cons)) < *len)
+ *len = XENSTORE_RING_SIZE - (prod - cons);
+ return buf + MASK_XENSTORE_IDX(prod);
+}
+
+static const void *get_input_chunk(XENSTORE_RING_IDX cons,
+ XENSTORE_RING_IDX prod,
+ const char *buf, uint32_t *len)
+{
+ *len = XENSTORE_RING_SIZE - MASK_XENSTORE_IDX(cons);
+ if ((prod - cons) < *len)
+ *len = prod - cons;
+ return buf + MASK_XENSTORE_IDX(cons);
+}
+
+/**
+ * xb_write - low level write
+ * @data: buffer to send
+ * @len: length of buffer
+ *
+ * Returns 0 on success, error otherwise.
+ */
+int xb_write(const void *data, unsigned len)
+{
+ struct xenstore_domain_interface *intf = xen_store_interface;
+ XENSTORE_RING_IDX cons, prod;
+ int rc;
+
+ while (len != 0) {
+ void *dst;
+ unsigned int avail;
+
+ rc = wait_event_interruptible(
+ xb_waitq,
+ (intf->req_prod - intf->req_cons) !=
+ XENSTORE_RING_SIZE);
+ if (rc < 0)
+ return rc;
+
+ /* Read indexes, then verify. */
+ cons = intf->req_cons;
+ prod = intf->req_prod;
+ if (!check_indexes(cons, prod)) {
+ intf->req_cons = intf->req_prod = 0;
+ return -EIO;
+ }
+
+ dst = get_output_chunk(cons, prod, intf->req, &avail);
+ if (avail == 0)
+ continue;
+ if (avail > len)
+ avail = len;
+
+ /* Must write data /after/ reading the consumer index. */
+ mb();
+
+ memcpy(dst, data, avail);
+ data += avail;
+ len -= avail;
+
+ /* Other side must not see new producer until data is there. */
+ wmb();
+ intf->req_prod += avail;
+
+ /* Implies mb(): other side will see the updated producer. */
+ notify_remote_via_evtchn(xen_store_evtchn);
+ }
+
+ return 0;
+}
+
+int xb_data_to_read(void)
+{
+ struct xenstore_domain_interface *intf = xen_store_interface;
+ return (intf->rsp_cons != intf->rsp_prod);
+}
+
+int xb_wait_for_data_to_read(void)
+{
+ return wait_event_interruptible(xb_waitq, xb_data_to_read());
+}
+
+int xb_read(void *data, unsigned len)
+{
+ struct xenstore_domain_interface *intf = xen_store_interface;
+ XENSTORE_RING_IDX cons, prod;
+ int rc;
+
+ while (len != 0) {
+ unsigned int avail;
+ const char *src;
+
+ rc = xb_wait_for_data_to_read();
+ if (rc < 0)
+ return rc;
+
+ /* Read indexes, then verify. */
+ cons = intf->rsp_cons;
+ prod = intf->rsp_prod;
+ if (!check_indexes(cons, prod)) {
+ intf->rsp_cons = intf->rsp_prod = 0;
+ return -EIO;
+ }
+
+ src = get_input_chunk(cons, prod, intf->rsp, &avail);
+ if (avail == 0)
+ continue;
+ if (avail > len)
+ avail = len;
+
+ /* Must read data /after/ reading the producer index. */
+ rmb();
+
+ memcpy(data, src, avail);
+ data += avail;
+ len -= avail;
+
+ /* Other side must not see free space until we've copied out */
+ mb();
+ intf->rsp_cons += avail;
+
+ pr_debug("Finished read of %i bytes (%i to go)\n", avail, len);
+
+ /* Implies mb(): other side will see the updated consumer. */
+ notify_remote_via_evtchn(xen_store_evtchn);
+ }
+
+ return 0;
+}
+
+/**
+ * xb_init_comms - Set up interrupt handler off store event channel.
+ */
+int xb_init_comms(void)
+{
+ struct xenstore_domain_interface *intf = xen_store_interface;
+
+ if (intf->req_prod != intf->req_cons)
+ printk(KERN_ERR "XENBUS request ring is not quiescent "
+ "(%08x:%08x)!\n", intf->req_cons, intf->req_prod);
+
+ if (intf->rsp_prod != intf->rsp_cons) {
+ printk(KERN_WARNING "XENBUS response ring is not quiescent "
+ "(%08x:%08x): fixing up\n",
+ intf->rsp_cons, intf->rsp_prod);
+ intf->rsp_cons = intf->rsp_prod;
+ }
+
+ if (xenbus_irq) {
+ /* Already have an irq; assume we're resuming */
+ rebind_evtchn_irq(xen_store_evtchn, xenbus_irq);
+ } else {
+ int err;
+ err = bind_evtchn_to_irqhandler(xen_store_evtchn, wake_waiting,
+ 0, "xenbus", &xb_waitq);
+ if (err <= 0) {
+ printk(KERN_ERR "XENBUS request irq failed %i\n", err);
+ return err;
+ }
+
+ xenbus_irq = err;
+ }
+
+ return 0;
+}
diff --git a/drivers/xen/xenbus/xenbus_comms.h b/drivers/xen/xenbus/xenbus_comms.h
new file mode 100644
index 00000000..c21db751
--- /dev/null
+++ b/drivers/xen/xenbus/xenbus_comms.h
@@ -0,0 +1,46 @@
+/*
+ * Private include for xenbus communications.
+ *
+ * Copyright (C) 2005 Rusty Russell, IBM Corporation
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation; or, when distributed
+ * separately from the Linux kernel or incorporated into other
+ * software packages, subject to the following license:
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this source file (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use, copy, modify,
+ * merge, publish, distribute, sublicense, and/or sell copies of the Software,
+ * and to permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#ifndef _XENBUS_COMMS_H
+#define _XENBUS_COMMS_H
+
+int xs_init(void);
+int xb_init_comms(void);
+
+/* Low level routines. */
+int xb_write(const void *data, unsigned len);
+int xb_read(void *data, unsigned len);
+int xb_data_to_read(void);
+int xb_wait_for_data_to_read(void);
+int xs_input_avail(void);
+extern struct xenstore_domain_interface *xen_store_interface;
+extern int xen_store_evtchn;
+
+#endif /* _XENBUS_COMMS_H */
diff --git a/drivers/xen/xenbus/xenbus_probe.c b/drivers/xen/xenbus/xenbus_probe.c
new file mode 100644
index 00000000..73976955
--- /dev/null
+++ b/drivers/xen/xenbus/xenbus_probe.c
@@ -0,0 +1,786 @@
+/******************************************************************************
+ * Talks to Xen Store to figure out what devices we have.
+ *
+ * Copyright (C) 2005 Rusty Russell, IBM Corporation
+ * Copyright (C) 2005 Mike Wray, Hewlett-Packard
+ * Copyright (C) 2005, 2006 XenSource Ltd
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation; or, when distributed
+ * separately from the Linux kernel or incorporated into other
+ * software packages, subject to the following license:
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this source file (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use, copy, modify,
+ * merge, publish, distribute, sublicense, and/or sell copies of the Software,
+ * and to permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#define DPRINTK(fmt, args...) \
+ pr_debug("xenbus_probe (%s:%d) " fmt ".\n", \
+ __func__, __LINE__, ##args)
+
+#include <linux/kernel.h>
+#include <linux/err.h>
+#include <linux/string.h>
+#include <linux/ctype.h>
+#include <linux/fcntl.h>
+#include <linux/mm.h>
+#include <linux/proc_fs.h>
+#include <linux/notifier.h>
+#include <linux/kthread.h>
+#include <linux/mutex.h>
+#include <linux/io.h>
+#include <linux/slab.h>
+
+#include <asm/page.h>
+#include <asm/pgtable.h>
+#include <asm/xen/hypervisor.h>
+
+#include <xen/xen.h>
+#include <xen/xenbus.h>
+#include <xen/events.h>
+#include <xen/page.h>
+
+#include <xen/hvm.h>
+
+#include "xenbus_comms.h"
+#include "xenbus_probe.h"
+
+
+int xen_store_evtchn;
+EXPORT_SYMBOL_GPL(xen_store_evtchn);
+
+struct xenstore_domain_interface *xen_store_interface;
+EXPORT_SYMBOL_GPL(xen_store_interface);
+
+static unsigned long xen_store_mfn;
+
+static BLOCKING_NOTIFIER_HEAD(xenstore_chain);
+
+/* If something in array of ids matches this device, return it. */
+static const struct xenbus_device_id *
+match_device(const struct xenbus_device_id *arr, struct xenbus_device *dev)
+{
+ for (; *arr->devicetype != '\0'; arr++) {
+ if (!strcmp(arr->devicetype, dev->devicetype))
+ return arr;
+ }
+ return NULL;
+}
+
+int xenbus_match(struct device *_dev, struct device_driver *_drv)
+{
+ struct xenbus_driver *drv = to_xenbus_driver(_drv);
+
+ if (!drv->ids)
+ return 0;
+
+ return match_device(drv->ids, to_xenbus_device(_dev)) != NULL;
+}
+EXPORT_SYMBOL_GPL(xenbus_match);
+
+
+static void free_otherend_details(struct xenbus_device *dev)
+{
+ kfree(dev->otherend);
+ dev->otherend = NULL;
+}
+
+
+static void free_otherend_watch(struct xenbus_device *dev)
+{
+ if (dev->otherend_watch.node) {
+ unregister_xenbus_watch(&dev->otherend_watch);
+ kfree(dev->otherend_watch.node);
+ dev->otherend_watch.node = NULL;
+ }
+}
+
+
+static int talk_to_otherend(struct xenbus_device *dev)
+{
+ struct xenbus_driver *drv = to_xenbus_driver(dev->dev.driver);
+
+ free_otherend_watch(dev);
+ free_otherend_details(dev);
+
+ return drv->read_otherend_details(dev);
+}
+
+
+
+static int watch_otherend(struct xenbus_device *dev)
+{
+ struct xen_bus_type *bus =
+ container_of(dev->dev.bus, struct xen_bus_type, bus);
+
+ return xenbus_watch_pathfmt(dev, &dev->otherend_watch,
+ bus->otherend_changed,
+ "%s/%s", dev->otherend, "state");
+}
+
+
+int xenbus_read_otherend_details(struct xenbus_device *xendev,
+ char *id_node, char *path_node)
+{
+ int err = xenbus_gather(XBT_NIL, xendev->nodename,
+ id_node, "%i", &xendev->otherend_id,
+ path_node, NULL, &xendev->otherend,
+ NULL);
+ if (err) {
+ xenbus_dev_fatal(xendev, err,
+ "reading other end details from %s",
+ xendev->nodename);
+ return err;
+ }
+ if (strlen(xendev->otherend) == 0 ||
+ !xenbus_exists(XBT_NIL, xendev->otherend, "")) {
+ xenbus_dev_fatal(xendev, -ENOENT,
+ "unable to read other end from %s. "
+ "missing or inaccessible.",
+ xendev->nodename);
+ free_otherend_details(xendev);
+ return -ENOENT;
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(xenbus_read_otherend_details);
+
+void xenbus_otherend_changed(struct xenbus_watch *watch,
+ const char **vec, unsigned int len,
+ int ignore_on_shutdown)
+{
+ struct xenbus_device *dev =
+ container_of(watch, struct xenbus_device, otherend_watch);
+ struct xenbus_driver *drv = to_xenbus_driver(dev->dev.driver);
+ enum xenbus_state state;
+
+ /* Protect us against watches firing on old details when the otherend
+ details change, say immediately after a resume. */
+ if (!dev->otherend ||
+ strncmp(dev->otherend, vec[XS_WATCH_PATH],
+ strlen(dev->otherend))) {
+ dev_dbg(&dev->dev, "Ignoring watch at %s\n",
+ vec[XS_WATCH_PATH]);
+ return;
+ }
+
+ state = xenbus_read_driver_state(dev->otherend);
+
+ dev_dbg(&dev->dev, "state is %d, (%s), %s, %s\n",
+ state, xenbus_strstate(state), dev->otherend_watch.node,
+ vec[XS_WATCH_PATH]);
+
+ /*
+ * Ignore xenbus transitions during shutdown. This prevents us doing
+ * work that can fail e.g., when the rootfs is gone.
+ */
+ if (system_state > SYSTEM_RUNNING) {
+ if (ignore_on_shutdown && (state == XenbusStateClosing))
+ xenbus_frontend_closed(dev);
+ return;
+ }
+
+ if (drv->otherend_changed)
+ drv->otherend_changed(dev, state);
+}
+EXPORT_SYMBOL_GPL(xenbus_otherend_changed);
+
+int xenbus_dev_probe(struct device *_dev)
+{
+ struct xenbus_device *dev = to_xenbus_device(_dev);
+ struct xenbus_driver *drv = to_xenbus_driver(_dev->driver);
+ const struct xenbus_device_id *id;
+ int err;
+
+ DPRINTK("%s", dev->nodename);
+
+ if (!drv->probe) {
+ err = -ENODEV;
+ goto fail;
+ }
+
+ id = match_device(drv->ids, dev);
+ if (!id) {
+ err = -ENODEV;
+ goto fail;
+ }
+
+ err = talk_to_otherend(dev);
+ if (err) {
+ dev_warn(&dev->dev, "talk_to_otherend on %s failed.\n",
+ dev->nodename);
+ return err;
+ }
+
+ err = drv->probe(dev, id);
+ if (err)
+ goto fail;
+
+ err = watch_otherend(dev);
+ if (err) {
+ dev_warn(&dev->dev, "watch_otherend on %s failed.\n",
+ dev->nodename);
+ return err;
+ }
+
+ return 0;
+fail:
+ xenbus_dev_error(dev, err, "xenbus_dev_probe on %s", dev->nodename);
+ xenbus_switch_state(dev, XenbusStateClosed);
+ return err;
+}
+EXPORT_SYMBOL_GPL(xenbus_dev_probe);
+
+int xenbus_dev_remove(struct device *_dev)
+{
+ struct xenbus_device *dev = to_xenbus_device(_dev);
+ struct xenbus_driver *drv = to_xenbus_driver(_dev->driver);
+
+ DPRINTK("%s", dev->nodename);
+
+ free_otherend_watch(dev);
+ free_otherend_details(dev);
+
+ if (drv->remove)
+ drv->remove(dev);
+
+ xenbus_switch_state(dev, XenbusStateClosed);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(xenbus_dev_remove);
+
+void xenbus_dev_shutdown(struct device *_dev)
+{
+ struct xenbus_device *dev = to_xenbus_device(_dev);
+ unsigned long timeout = 5*HZ;
+
+ DPRINTK("%s", dev->nodename);
+
+ get_device(&dev->dev);
+ if (dev->state != XenbusStateConnected) {
+ printk(KERN_INFO "%s: %s: %s != Connected, skipping\n", __func__,
+ dev->nodename, xenbus_strstate(dev->state));
+ goto out;
+ }
+ xenbus_switch_state(dev, XenbusStateClosing);
+ timeout = wait_for_completion_timeout(&dev->down, timeout);
+ if (!timeout)
+ printk(KERN_INFO "%s: %s timeout closing device\n",
+ __func__, dev->nodename);
+ out:
+ put_device(&dev->dev);
+}
+EXPORT_SYMBOL_GPL(xenbus_dev_shutdown);
+
+int xenbus_register_driver_common(struct xenbus_driver *drv,
+ struct xen_bus_type *bus,
+ struct module *owner,
+ const char *mod_name)
+{
+ drv->driver.name = drv->name;
+ drv->driver.bus = &bus->bus;
+ drv->driver.owner = owner;
+ drv->driver.mod_name = mod_name;
+
+ return driver_register(&drv->driver);
+}
+EXPORT_SYMBOL_GPL(xenbus_register_driver_common);
+
+void xenbus_unregister_driver(struct xenbus_driver *drv)
+{
+ driver_unregister(&drv->driver);
+}
+EXPORT_SYMBOL_GPL(xenbus_unregister_driver);
+
+struct xb_find_info
+{
+ struct xenbus_device *dev;
+ const char *nodename;
+};
+
+static int cmp_dev(struct device *dev, void *data)
+{
+ struct xenbus_device *xendev = to_xenbus_device(dev);
+ struct xb_find_info *info = data;
+
+ if (!strcmp(xendev->nodename, info->nodename)) {
+ info->dev = xendev;
+ get_device(dev);
+ return 1;
+ }
+ return 0;
+}
+
+struct xenbus_device *xenbus_device_find(const char *nodename,
+ struct bus_type *bus)
+{
+ struct xb_find_info info = { .dev = NULL, .nodename = nodename };
+
+ bus_for_each_dev(bus, NULL, &info, cmp_dev);
+ return info.dev;
+}
+
+static int cleanup_dev(struct device *dev, void *data)
+{
+ struct xenbus_device *xendev = to_xenbus_device(dev);
+ struct xb_find_info *info = data;
+ int len = strlen(info->nodename);
+
+ DPRINTK("%s", info->nodename);
+
+ /* Match the info->nodename path, or any subdirectory of that path. */
+ if (strncmp(xendev->nodename, info->nodename, len))
+ return 0;
+
+ /* If the node name is longer, ensure it really is a subdirectory. */
+ if ((strlen(xendev->nodename) > len) && (xendev->nodename[len] != '/'))
+ return 0;
+
+ info->dev = xendev;
+ get_device(dev);
+ return 1;
+}
+
+static void xenbus_cleanup_devices(const char *path, struct bus_type *bus)
+{
+ struct xb_find_info info = { .nodename = path };
+
+ do {
+ info.dev = NULL;
+ bus_for_each_dev(bus, NULL, &info, cleanup_dev);
+ if (info.dev) {
+ device_unregister(&info.dev->dev);
+ put_device(&info.dev->dev);
+ }
+ } while (info.dev);
+}
+
+static void xenbus_dev_release(struct device *dev)
+{
+ if (dev)
+ kfree(to_xenbus_device(dev));
+}
+
+static ssize_t xendev_show_nodename(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ return sprintf(buf, "%s\n", to_xenbus_device(dev)->nodename);
+}
+static DEVICE_ATTR(nodename, S_IRUSR | S_IRGRP | S_IROTH, xendev_show_nodename, NULL);
+
+static ssize_t xendev_show_devtype(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ return sprintf(buf, "%s\n", to_xenbus_device(dev)->devicetype);
+}
+static DEVICE_ATTR(devtype, S_IRUSR | S_IRGRP | S_IROTH, xendev_show_devtype, NULL);
+
+static ssize_t xendev_show_modalias(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ return sprintf(buf, "xen:%s\n", to_xenbus_device(dev)->devicetype);
+}
+static DEVICE_ATTR(modalias, S_IRUSR | S_IRGRP | S_IROTH, xendev_show_modalias, NULL);
+
+int xenbus_probe_node(struct xen_bus_type *bus,
+ const char *type,
+ const char *nodename)
+{
+ char devname[XEN_BUS_ID_SIZE];
+ int err;
+ struct xenbus_device *xendev;
+ size_t stringlen;
+ char *tmpstring;
+
+ enum xenbus_state state = xenbus_read_driver_state(nodename);
+
+ if (state != XenbusStateInitialising) {
+ /* Device is not new, so ignore it. This can happen if a
+ device is going away after switching to Closed. */
+ return 0;
+ }
+
+ stringlen = strlen(nodename) + 1 + strlen(type) + 1;
+ xendev = kzalloc(sizeof(*xendev) + stringlen, GFP_KERNEL);
+ if (!xendev)
+ return -ENOMEM;
+
+ xendev->state = XenbusStateInitialising;
+
+ /* Copy the strings into the extra space. */
+
+ tmpstring = (char *)(xendev + 1);
+ strcpy(tmpstring, nodename);
+ xendev->nodename = tmpstring;
+
+ tmpstring += strlen(tmpstring) + 1;
+ strcpy(tmpstring, type);
+ xendev->devicetype = tmpstring;
+ init_completion(&xendev->down);
+
+ xendev->dev.bus = &bus->bus;
+ xendev->dev.release = xenbus_dev_release;
+
+ err = bus->get_bus_id(devname, xendev->nodename);
+ if (err)
+ goto fail;
+
+ dev_set_name(&xendev->dev, devname);
+
+ /* Register with generic device framework. */
+ err = device_register(&xendev->dev);
+ if (err)
+ goto fail;
+
+ err = device_create_file(&xendev->dev, &dev_attr_nodename);
+ if (err)
+ goto fail_unregister;
+
+ err = device_create_file(&xendev->dev, &dev_attr_devtype);
+ if (err)
+ goto fail_remove_nodename;
+
+ err = device_create_file(&xendev->dev, &dev_attr_modalias);
+ if (err)
+ goto fail_remove_devtype;
+
+ return 0;
+fail_remove_devtype:
+ device_remove_file(&xendev->dev, &dev_attr_devtype);
+fail_remove_nodename:
+ device_remove_file(&xendev->dev, &dev_attr_nodename);
+fail_unregister:
+ device_unregister(&xendev->dev);
+fail:
+ kfree(xendev);
+ return err;
+}
+EXPORT_SYMBOL_GPL(xenbus_probe_node);
+
+static int xenbus_probe_device_type(struct xen_bus_type *bus, const char *type)
+{
+ int err = 0;
+ char **dir;
+ unsigned int dir_n = 0;
+ int i;
+
+ dir = xenbus_directory(XBT_NIL, bus->root, type, &dir_n);
+ if (IS_ERR(dir))
+ return PTR_ERR(dir);
+
+ for (i = 0; i < dir_n; i++) {
+ err = bus->probe(bus, type, dir[i]);
+ if (err)
+ break;
+ }
+
+ kfree(dir);
+ return err;
+}
+
+int xenbus_probe_devices(struct xen_bus_type *bus)
+{
+ int err = 0;
+ char **dir;
+ unsigned int i, dir_n;
+
+ dir = xenbus_directory(XBT_NIL, bus->root, "", &dir_n);
+ if (IS_ERR(dir))
+ return PTR_ERR(dir);
+
+ for (i = 0; i < dir_n; i++) {
+ err = xenbus_probe_device_type(bus, dir[i]);
+ if (err)
+ break;
+ }
+
+ kfree(dir);
+ return err;
+}
+EXPORT_SYMBOL_GPL(xenbus_probe_devices);
+
+static unsigned int char_count(const char *str, char c)
+{
+ unsigned int i, ret = 0;
+
+ for (i = 0; str[i]; i++)
+ if (str[i] == c)
+ ret++;
+ return ret;
+}
+
+static int strsep_len(const char *str, char c, unsigned int len)
+{
+ unsigned int i;
+
+ for (i = 0; str[i]; i++)
+ if (str[i] == c) {
+ if (len == 0)
+ return i;
+ len--;
+ }
+ return (len == 0) ? i : -ERANGE;
+}
+
+void xenbus_dev_changed(const char *node, struct xen_bus_type *bus)
+{
+ int exists, rootlen;
+ struct xenbus_device *dev;
+ char type[XEN_BUS_ID_SIZE];
+ const char *p, *root;
+
+ if (char_count(node, '/') < 2)
+ return;
+
+ exists = xenbus_exists(XBT_NIL, node, "");
+ if (!exists) {
+ xenbus_cleanup_devices(node, &bus->bus);
+ return;
+ }
+
+ /* backend/<type>/... or device/<type>/... */
+ p = strchr(node, '/') + 1;
+ snprintf(type, XEN_BUS_ID_SIZE, "%.*s", (int)strcspn(p, "/"), p);
+ type[XEN_BUS_ID_SIZE-1] = '\0';
+
+ rootlen = strsep_len(node, '/', bus->levels);
+ if (rootlen < 0)
+ return;
+ root = kasprintf(GFP_KERNEL, "%.*s", rootlen, node);
+ if (!root)
+ return;
+
+ dev = xenbus_device_find(root, &bus->bus);
+ if (!dev)
+ xenbus_probe_node(bus, type, root);
+ else
+ put_device(&dev->dev);
+
+ kfree(root);
+}
+EXPORT_SYMBOL_GPL(xenbus_dev_changed);
+
+int xenbus_dev_suspend(struct device *dev)
+{
+ int err = 0;
+ struct xenbus_driver *drv;
+ struct xenbus_device *xdev
+ = container_of(dev, struct xenbus_device, dev);
+
+ DPRINTK("%s", xdev->nodename);
+
+ if (dev->driver == NULL)
+ return 0;
+ drv = to_xenbus_driver(dev->driver);
+ if (drv->suspend)
+ err = drv->suspend(xdev);
+ if (err)
+ printk(KERN_WARNING
+ "xenbus: suspend %s failed: %i\n", dev_name(dev), err);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(xenbus_dev_suspend);
+
+int xenbus_dev_resume(struct device *dev)
+{
+ int err;
+ struct xenbus_driver *drv;
+ struct xenbus_device *xdev
+ = container_of(dev, struct xenbus_device, dev);
+
+ DPRINTK("%s", xdev->nodename);
+
+ if (dev->driver == NULL)
+ return 0;
+ drv = to_xenbus_driver(dev->driver);
+ err = talk_to_otherend(xdev);
+ if (err) {
+ printk(KERN_WARNING
+ "xenbus: resume (talk_to_otherend) %s failed: %i\n",
+ dev_name(dev), err);
+ return err;
+ }
+
+ xdev->state = XenbusStateInitialising;
+
+ if (drv->resume) {
+ err = drv->resume(xdev);
+ if (err) {
+ printk(KERN_WARNING
+ "xenbus: resume %s failed: %i\n",
+ dev_name(dev), err);
+ return err;
+ }
+ }
+
+ err = watch_otherend(xdev);
+ if (err) {
+ printk(KERN_WARNING
+ "xenbus_probe: resume (watch_otherend) %s failed: "
+ "%d.\n", dev_name(dev), err);
+ return err;
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(xenbus_dev_resume);
+
+int xenbus_dev_cancel(struct device *dev)
+{
+ /* Do nothing */
+ DPRINTK("cancel");
+ return 0;
+}
+EXPORT_SYMBOL_GPL(xenbus_dev_cancel);
+
+/* A flag to determine if xenstored is 'ready' (i.e. has started) */
+int xenstored_ready = 0;
+
+
+int register_xenstore_notifier(struct notifier_block *nb)
+{
+ int ret = 0;
+
+ if (xenstored_ready > 0)
+ ret = nb->notifier_call(nb, 0, NULL);
+ else
+ blocking_notifier_chain_register(&xenstore_chain, nb);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(register_xenstore_notifier);
+
+void unregister_xenstore_notifier(struct notifier_block *nb)
+{
+ blocking_notifier_chain_unregister(&xenstore_chain, nb);
+}
+EXPORT_SYMBOL_GPL(unregister_xenstore_notifier);
+
+void xenbus_probe(struct work_struct *unused)
+{
+ xenstored_ready = 1;
+
+ /* Notify others that xenstore is up */
+ blocking_notifier_call_chain(&xenstore_chain, 0, NULL);
+}
+EXPORT_SYMBOL_GPL(xenbus_probe);
+
+static int __init xenbus_probe_initcall(void)
+{
+ if (!xen_domain())
+ return -ENODEV;
+
+ if (xen_initial_domain() || xen_hvm_domain())
+ return 0;
+
+ xenbus_probe(NULL);
+ return 0;
+}
+
+device_initcall(xenbus_probe_initcall);
+
+static int __init xenbus_init(void)
+{
+ int err = 0;
+ unsigned long page = 0;
+
+ DPRINTK("");
+
+ err = -ENODEV;
+ if (!xen_domain())
+ return err;
+
+ /*
+ * Domain0 doesn't have a store_evtchn or store_mfn yet.
+ */
+ if (xen_initial_domain()) {
+ struct evtchn_alloc_unbound alloc_unbound;
+
+ /* Allocate Xenstore page */
+ page = get_zeroed_page(GFP_KERNEL);
+ if (!page)
+ goto out_error;
+
+ xen_store_mfn = xen_start_info->store_mfn =
+ pfn_to_mfn(virt_to_phys((void *)page) >>
+ PAGE_SHIFT);
+
+ /* Next allocate a local port which xenstored can bind to */
+ alloc_unbound.dom = DOMID_SELF;
+ alloc_unbound.remote_dom = 0;
+
+ err = HYPERVISOR_event_channel_op(EVTCHNOP_alloc_unbound,
+ &alloc_unbound);
+ if (err == -ENOSYS)
+ goto out_error;
+
+ BUG_ON(err);
+ xen_store_evtchn = xen_start_info->store_evtchn =
+ alloc_unbound.port;
+
+ xen_store_interface = mfn_to_virt(xen_store_mfn);
+ } else {
+ if (xen_hvm_domain()) {
+ uint64_t v = 0;
+ err = hvm_get_parameter(HVM_PARAM_STORE_EVTCHN, &v);
+ if (err)
+ goto out_error;
+ xen_store_evtchn = (int)v;
+ err = hvm_get_parameter(HVM_PARAM_STORE_PFN, &v);
+ if (err)
+ goto out_error;
+ xen_store_mfn = (unsigned long)v;
+ xen_store_interface = ioremap(xen_store_mfn << PAGE_SHIFT, PAGE_SIZE);
+ } else {
+ xen_store_evtchn = xen_start_info->store_evtchn;
+ xen_store_mfn = xen_start_info->store_mfn;
+ xen_store_interface = mfn_to_virt(xen_store_mfn);
+ xenstored_ready = 1;
+ }
+ }
+
+ /* Initialize the interface to xenstore. */
+ err = xs_init();
+ if (err) {
+ printk(KERN_WARNING
+ "XENBUS: Error initializing xenstore comms: %i\n", err);
+ goto out_error;
+ }
+
+#ifdef CONFIG_XEN_COMPAT_XENFS
+ /*
+ * Create xenfs mountpoint in /proc for compatibility with
+ * utilities that expect to find "xenbus" under "/proc/xen".
+ */
+ proc_mkdir("xen", NULL);
+#endif
+
+ return 0;
+
+ out_error:
+ if (page != 0)
+ free_page(page);
+
+ return err;
+}
+
+postcore_initcall(xenbus_init);
+
+MODULE_LICENSE("GPL");
diff --git a/drivers/xen/xenbus/xenbus_probe.h b/drivers/xen/xenbus/xenbus_probe.h
new file mode 100644
index 00000000..888b9900
--- /dev/null
+++ b/drivers/xen/xenbus/xenbus_probe.h
@@ -0,0 +1,78 @@
+/******************************************************************************
+ * xenbus_probe.h
+ *
+ * Talks to Xen Store to figure out what devices we have.
+ *
+ * Copyright (C) 2005 Rusty Russell, IBM Corporation
+ * Copyright (C) 2005 XenSource Ltd.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation; or, when distributed
+ * separately from the Linux kernel or incorporated into other
+ * software packages, subject to the following license:
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this source file (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use, copy, modify,
+ * merge, publish, distribute, sublicense, and/or sell copies of the Software,
+ * and to permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#ifndef _XENBUS_PROBE_H
+#define _XENBUS_PROBE_H
+
+#define XEN_BUS_ID_SIZE 20
+
+struct xen_bus_type
+{
+ char *root;
+ unsigned int levels;
+ int (*get_bus_id)(char bus_id[XEN_BUS_ID_SIZE], const char *nodename);
+ int (*probe)(struct xen_bus_type *bus, const char *type,
+ const char *dir);
+ void (*otherend_changed)(struct xenbus_watch *watch, const char **vec,
+ unsigned int len);
+ struct bus_type bus;
+};
+
+extern int xenbus_match(struct device *_dev, struct device_driver *_drv);
+extern int xenbus_dev_probe(struct device *_dev);
+extern int xenbus_dev_remove(struct device *_dev);
+extern int xenbus_register_driver_common(struct xenbus_driver *drv,
+ struct xen_bus_type *bus,
+ struct module *owner,
+ const char *mod_name);
+extern int xenbus_probe_node(struct xen_bus_type *bus,
+ const char *type,
+ const char *nodename);
+extern int xenbus_probe_devices(struct xen_bus_type *bus);
+
+extern void xenbus_dev_changed(const char *node, struct xen_bus_type *bus);
+
+extern void xenbus_dev_shutdown(struct device *_dev);
+
+extern int xenbus_dev_suspend(struct device *dev);
+extern int xenbus_dev_resume(struct device *dev);
+extern int xenbus_dev_cancel(struct device *dev);
+
+extern void xenbus_otherend_changed(struct xenbus_watch *watch,
+ const char **vec, unsigned int len,
+ int ignore_on_shutdown);
+
+extern int xenbus_read_otherend_details(struct xenbus_device *xendev,
+ char *id_node, char *path_node);
+
+#endif
diff --git a/drivers/xen/xenbus/xenbus_probe_backend.c b/drivers/xen/xenbus/xenbus_probe_backend.c
new file mode 100644
index 00000000..6cf467bf
--- /dev/null
+++ b/drivers/xen/xenbus/xenbus_probe_backend.c
@@ -0,0 +1,276 @@
+/******************************************************************************
+ * Talks to Xen Store to figure out what devices we have (backend half).
+ *
+ * Copyright (C) 2005 Rusty Russell, IBM Corporation
+ * Copyright (C) 2005 Mike Wray, Hewlett-Packard
+ * Copyright (C) 2005, 2006 XenSource Ltd
+ * Copyright (C) 2007 Solarflare Communications, Inc.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation; or, when distributed
+ * separately from the Linux kernel or incorporated into other
+ * software packages, subject to the following license:
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this source file (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use, copy, modify,
+ * merge, publish, distribute, sublicense, and/or sell copies of the Software,
+ * and to permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#define DPRINTK(fmt, args...) \
+ pr_debug("xenbus_probe (%s:%d) " fmt ".\n", \
+ __func__, __LINE__, ##args)
+
+#include <linux/kernel.h>
+#include <linux/err.h>
+#include <linux/string.h>
+#include <linux/ctype.h>
+#include <linux/fcntl.h>
+#include <linux/mm.h>
+#include <linux/notifier.h>
+
+#include <asm/page.h>
+#include <asm/pgtable.h>
+#include <asm/xen/hypervisor.h>
+#include <asm/hypervisor.h>
+#include <xen/xenbus.h>
+#include <xen/features.h>
+
+#include "xenbus_comms.h"
+#include "xenbus_probe.h"
+
+/* backend/<type>/<fe-uuid>/<id> => <type>-<fe-domid>-<id> */
+static int backend_bus_id(char bus_id[XEN_BUS_ID_SIZE], const char *nodename)
+{
+ int domid, err;
+ const char *devid, *type, *frontend;
+ unsigned int typelen;
+
+ type = strchr(nodename, '/');
+ if (!type)
+ return -EINVAL;
+ type++;
+ typelen = strcspn(type, "/");
+ if (!typelen || type[typelen] != '/')
+ return -EINVAL;
+
+ devid = strrchr(nodename, '/') + 1;
+
+ err = xenbus_gather(XBT_NIL, nodename, "frontend-id", "%i", &domid,
+ "frontend", NULL, &frontend,
+ NULL);
+ if (err)
+ return err;
+ if (strlen(frontend) == 0)
+ err = -ERANGE;
+ if (!err && !xenbus_exists(XBT_NIL, frontend, ""))
+ err = -ENOENT;
+ kfree(frontend);
+
+ if (err)
+ return err;
+
+ if (snprintf(bus_id, XEN_BUS_ID_SIZE, "%.*s-%i-%s",
+ typelen, type, domid, devid) >= XEN_BUS_ID_SIZE)
+ return -ENOSPC;
+ return 0;
+}
+
+static int xenbus_uevent_backend(struct device *dev,
+ struct kobj_uevent_env *env)
+{
+ struct xenbus_device *xdev;
+ struct xenbus_driver *drv;
+ struct xen_bus_type *bus;
+
+ DPRINTK("");
+
+ if (dev == NULL)
+ return -ENODEV;
+
+ xdev = to_xenbus_device(dev);
+ bus = container_of(xdev->dev.bus, struct xen_bus_type, bus);
+ if (xdev == NULL)
+ return -ENODEV;
+
+ /* stuff we want to pass to /sbin/hotplug */
+ if (add_uevent_var(env, "XENBUS_TYPE=%s", xdev->devicetype))
+ return -ENOMEM;
+
+ if (add_uevent_var(env, "XENBUS_PATH=%s", xdev->nodename))
+ return -ENOMEM;
+
+ if (add_uevent_var(env, "XENBUS_BASE_PATH=%s", bus->root))
+ return -ENOMEM;
+
+ if (dev->driver) {
+ drv = to_xenbus_driver(dev->driver);
+ if (drv && drv->uevent)
+ return drv->uevent(xdev, env);
+ }
+
+ return 0;
+}
+
+/* backend/<typename>/<frontend-uuid>/<name> */
+static int xenbus_probe_backend_unit(struct xen_bus_type *bus,
+ const char *dir,
+ const char *type,
+ const char *name)
+{
+ char *nodename;
+ int err;
+
+ nodename = kasprintf(GFP_KERNEL, "%s/%s", dir, name);
+ if (!nodename)
+ return -ENOMEM;
+
+ DPRINTK("%s\n", nodename);
+
+ err = xenbus_probe_node(bus, type, nodename);
+ kfree(nodename);
+ return err;
+}
+
+/* backend/<typename>/<frontend-domid> */
+static int xenbus_probe_backend(struct xen_bus_type *bus, const char *type,
+ const char *domid)
+{
+ char *nodename;
+ int err = 0;
+ char **dir;
+ unsigned int i, dir_n = 0;
+
+ DPRINTK("");
+
+ nodename = kasprintf(GFP_KERNEL, "%s/%s/%s", bus->root, type, domid);
+ if (!nodename)
+ return -ENOMEM;
+
+ dir = xenbus_directory(XBT_NIL, nodename, "", &dir_n);
+ if (IS_ERR(dir)) {
+ kfree(nodename);
+ return PTR_ERR(dir);
+ }
+
+ for (i = 0; i < dir_n; i++) {
+ err = xenbus_probe_backend_unit(bus, nodename, type, dir[i]);
+ if (err)
+ break;
+ }
+ kfree(dir);
+ kfree(nodename);
+ return err;
+}
+
+static void frontend_changed(struct xenbus_watch *watch,
+ const char **vec, unsigned int len)
+{
+ xenbus_otherend_changed(watch, vec, len, 0);
+}
+
+static struct device_attribute xenbus_backend_dev_attrs[] = {
+ __ATTR_NULL
+};
+
+static struct xen_bus_type xenbus_backend = {
+ .root = "backend",
+ .levels = 3, /* backend/type/<frontend>/<id> */
+ .get_bus_id = backend_bus_id,
+ .probe = xenbus_probe_backend,
+ .otherend_changed = frontend_changed,
+ .bus = {
+ .name = "xen-backend",
+ .match = xenbus_match,
+ .uevent = xenbus_uevent_backend,
+ .probe = xenbus_dev_probe,
+ .remove = xenbus_dev_remove,
+ .shutdown = xenbus_dev_shutdown,
+ .dev_attrs = xenbus_backend_dev_attrs,
+ },
+};
+
+static void backend_changed(struct xenbus_watch *watch,
+ const char **vec, unsigned int len)
+{
+ DPRINTK("");
+
+ xenbus_dev_changed(vec[XS_WATCH_PATH], &xenbus_backend);
+}
+
+static struct xenbus_watch be_watch = {
+ .node = "backend",
+ .callback = backend_changed,
+};
+
+static int read_frontend_details(struct xenbus_device *xendev)
+{
+ return xenbus_read_otherend_details(xendev, "frontend-id", "frontend");
+}
+
+int xenbus_dev_is_online(struct xenbus_device *dev)
+{
+ int rc, val;
+
+ rc = xenbus_scanf(XBT_NIL, dev->nodename, "online", "%d", &val);
+ if (rc != 1)
+ val = 0; /* no online node present */
+
+ return val;
+}
+EXPORT_SYMBOL_GPL(xenbus_dev_is_online);
+
+int __xenbus_register_backend(struct xenbus_driver *drv,
+ struct module *owner, const char *mod_name)
+{
+ drv->read_otherend_details = read_frontend_details;
+
+ return xenbus_register_driver_common(drv, &xenbus_backend,
+ owner, mod_name);
+}
+EXPORT_SYMBOL_GPL(__xenbus_register_backend);
+
+static int backend_probe_and_watch(struct notifier_block *notifier,
+ unsigned long event,
+ void *data)
+{
+ /* Enumerate devices in xenstore and watch for changes. */
+ xenbus_probe_devices(&xenbus_backend);
+ register_xenbus_watch(&be_watch);
+
+ return NOTIFY_DONE;
+}
+
+static int __init xenbus_probe_backend_init(void)
+{
+ static struct notifier_block xenstore_notifier = {
+ .notifier_call = backend_probe_and_watch
+ };
+ int err;
+
+ DPRINTK("");
+
+ /* Register ourselves with the kernel bus subsystem */
+ err = bus_register(&xenbus_backend.bus);
+ if (err)
+ return err;
+
+ register_xenstore_notifier(&xenstore_notifier);
+
+ return 0;
+}
+subsys_initcall(xenbus_probe_backend_init);
diff --git a/drivers/xen/xenbus/xenbus_probe_frontend.c b/drivers/xen/xenbus/xenbus_probe_frontend.c
new file mode 100644
index 00000000..560f2176
--- /dev/null
+++ b/drivers/xen/xenbus/xenbus_probe_frontend.c
@@ -0,0 +1,338 @@
+#define DPRINTK(fmt, args...) \
+ pr_debug("xenbus_probe (%s:%d) " fmt ".\n", \
+ __func__, __LINE__, ##args)
+
+#include <linux/kernel.h>
+#include <linux/err.h>
+#include <linux/string.h>
+#include <linux/ctype.h>
+#include <linux/fcntl.h>
+#include <linux/mm.h>
+#include <linux/proc_fs.h>
+#include <linux/notifier.h>
+#include <linux/kthread.h>
+#include <linux/mutex.h>
+#include <linux/io.h>
+
+#include <asm/page.h>
+#include <asm/pgtable.h>
+#include <asm/xen/hypervisor.h>
+#include <xen/xenbus.h>
+#include <xen/events.h>
+#include <xen/page.h>
+
+#include <xen/platform_pci.h>
+
+#include "xenbus_comms.h"
+#include "xenbus_probe.h"
+
+
+/* device/<type>/<id> => <type>-<id> */
+static int frontend_bus_id(char bus_id[XEN_BUS_ID_SIZE], const char *nodename)
+{
+ nodename = strchr(nodename, '/');
+ if (!nodename || strlen(nodename + 1) >= XEN_BUS_ID_SIZE) {
+ printk(KERN_WARNING "XENBUS: bad frontend %s\n", nodename);
+ return -EINVAL;
+ }
+
+ strlcpy(bus_id, nodename + 1, XEN_BUS_ID_SIZE);
+ if (!strchr(bus_id, '/')) {
+ printk(KERN_WARNING "XENBUS: bus_id %s no slash\n", bus_id);
+ return -EINVAL;
+ }
+ *strchr(bus_id, '/') = '-';
+ return 0;
+}
+
+/* device/<typename>/<name> */
+static int xenbus_probe_frontend(struct xen_bus_type *bus, const char *type,
+ const char *name)
+{
+ char *nodename;
+ int err;
+
+ nodename = kasprintf(GFP_KERNEL, "%s/%s/%s", bus->root, type, name);
+ if (!nodename)
+ return -ENOMEM;
+
+ DPRINTK("%s", nodename);
+
+ err = xenbus_probe_node(bus, type, nodename);
+ kfree(nodename);
+ return err;
+}
+
+static int xenbus_uevent_frontend(struct device *_dev,
+ struct kobj_uevent_env *env)
+{
+ struct xenbus_device *dev = to_xenbus_device(_dev);
+
+ if (add_uevent_var(env, "MODALIAS=xen:%s", dev->devicetype))
+ return -ENOMEM;
+
+ return 0;
+}
+
+
+static void backend_changed(struct xenbus_watch *watch,
+ const char **vec, unsigned int len)
+{
+ xenbus_otherend_changed(watch, vec, len, 1);
+}
+
+static struct device_attribute xenbus_frontend_dev_attrs[] = {
+ __ATTR_NULL
+};
+
+static const struct dev_pm_ops xenbus_pm_ops = {
+ .suspend = xenbus_dev_suspend,
+ .resume = xenbus_dev_resume,
+ .freeze = xenbus_dev_suspend,
+ .thaw = xenbus_dev_cancel,
+ .restore = xenbus_dev_resume,
+};
+
+static struct xen_bus_type xenbus_frontend = {
+ .root = "device",
+ .levels = 2, /* device/type/<id> */
+ .get_bus_id = frontend_bus_id,
+ .probe = xenbus_probe_frontend,
+ .otherend_changed = backend_changed,
+ .bus = {
+ .name = "xen",
+ .match = xenbus_match,
+ .uevent = xenbus_uevent_frontend,
+ .probe = xenbus_dev_probe,
+ .remove = xenbus_dev_remove,
+ .shutdown = xenbus_dev_shutdown,
+ .dev_attrs = xenbus_frontend_dev_attrs,
+
+ .pm = &xenbus_pm_ops,
+ },
+};
+
+static void frontend_changed(struct xenbus_watch *watch,
+ const char **vec, unsigned int len)
+{
+ DPRINTK("");
+
+ xenbus_dev_changed(vec[XS_WATCH_PATH], &xenbus_frontend);
+}
+
+
+/* We watch for devices appearing and vanishing. */
+static struct xenbus_watch fe_watch = {
+ .node = "device",
+ .callback = frontend_changed,
+};
+
+static int read_backend_details(struct xenbus_device *xendev)
+{
+ return xenbus_read_otherend_details(xendev, "backend-id", "backend");
+}
+
+static int is_device_connecting(struct device *dev, void *data, bool ignore_nonessential)
+{
+ struct xenbus_device *xendev = to_xenbus_device(dev);
+ struct device_driver *drv = data;
+ struct xenbus_driver *xendrv;
+
+ /*
+ * A device with no driver will never connect. We care only about
+ * devices which should currently be in the process of connecting.
+ */
+ if (!dev->driver)
+ return 0;
+
+ /* Is this search limited to a particular driver? */
+ if (drv && (dev->driver != drv))
+ return 0;
+
+ if (ignore_nonessential) {
+ /* With older QEMU, for PVonHVM guests the guest config files
+ * could contain: vfb = [ 'vnc=1, vnclisten=0.0.0.0']
+ * which is nonsensical as there is no PV FB (there can be
+ * a PVKB) running as HVM guest. */
+
+ if ((strncmp(xendev->nodename, "device/vkbd", 11) == 0))
+ return 0;
+
+ if ((strncmp(xendev->nodename, "device/vfb", 10) == 0))
+ return 0;
+ }
+ xendrv = to_xenbus_driver(dev->driver);
+ return (xendev->state < XenbusStateConnected ||
+ (xendev->state == XenbusStateConnected &&
+ xendrv->is_ready && !xendrv->is_ready(xendev)));
+}
+static int essential_device_connecting(struct device *dev, void *data)
+{
+ return is_device_connecting(dev, data, true /* ignore PV[KBB+FB] */);
+}
+static int non_essential_device_connecting(struct device *dev, void *data)
+{
+ return is_device_connecting(dev, data, false);
+}
+
+static int exists_essential_connecting_device(struct device_driver *drv)
+{
+ return bus_for_each_dev(&xenbus_frontend.bus, NULL, drv,
+ essential_device_connecting);
+}
+static int exists_non_essential_connecting_device(struct device_driver *drv)
+{
+ return bus_for_each_dev(&xenbus_frontend.bus, NULL, drv,
+ non_essential_device_connecting);
+}
+
+static int print_device_status(struct device *dev, void *data)
+{
+ struct xenbus_device *xendev = to_xenbus_device(dev);
+ struct device_driver *drv = data;
+
+ /* Is this operation limited to a particular driver? */
+ if (drv && (dev->driver != drv))
+ return 0;
+
+ if (!dev->driver) {
+ /* Information only: is this too noisy? */
+ printk(KERN_INFO "XENBUS: Device with no driver: %s\n",
+ xendev->nodename);
+ } else if (xendev->state < XenbusStateConnected) {
+ enum xenbus_state rstate = XenbusStateUnknown;
+ if (xendev->otherend)
+ rstate = xenbus_read_driver_state(xendev->otherend);
+ printk(KERN_WARNING "XENBUS: Timeout connecting "
+ "to device: %s (local state %d, remote state %d)\n",
+ xendev->nodename, xendev->state, rstate);
+ }
+
+ return 0;
+}
+
+/* We only wait for device setup after most initcalls have run. */
+static int ready_to_wait_for_devices;
+
+static bool wait_loop(unsigned long start, unsigned int max_delay,
+ unsigned int *seconds_waited)
+{
+ if (time_after(jiffies, start + (*seconds_waited+5)*HZ)) {
+ if (!*seconds_waited)
+ printk(KERN_WARNING "XENBUS: Waiting for "
+ "devices to initialise: ");
+ *seconds_waited += 5;
+ printk("%us...", max_delay - *seconds_waited);
+ if (*seconds_waited == max_delay)
+ return true;
+ }
+
+ schedule_timeout_interruptible(HZ/10);
+
+ return false;
+}
+/*
+ * On a 5-minute timeout, wait for all devices currently configured. We need
+ * to do this to guarantee that the filesystems and / or network devices
+ * needed for boot are available, before we can allow the boot to proceed.
+ *
+ * This needs to be on a late_initcall, to happen after the frontend device
+ * drivers have been initialised, but before the root fs is mounted.
+ *
+ * A possible improvement here would be to have the tools add a per-device
+ * flag to the store entry, indicating whether it is needed at boot time.
+ * This would allow people who knew what they were doing to accelerate their
+ * boot slightly, but of course needs tools or manual intervention to set up
+ * those flags correctly.
+ */
+static void wait_for_devices(struct xenbus_driver *xendrv)
+{
+ unsigned long start = jiffies;
+ struct device_driver *drv = xendrv ? &xendrv->driver : NULL;
+ unsigned int seconds_waited = 0;
+
+ if (!ready_to_wait_for_devices || !xen_domain())
+ return;
+
+ while (exists_non_essential_connecting_device(drv))
+ if (wait_loop(start, 30, &seconds_waited))
+ break;
+
+ /* Skips PVKB and PVFB check.*/
+ while (exists_essential_connecting_device(drv))
+ if (wait_loop(start, 270, &seconds_waited))
+ break;
+
+ if (seconds_waited)
+ printk("\n");
+
+ bus_for_each_dev(&xenbus_frontend.bus, NULL, drv,
+ print_device_status);
+}
+
+int __xenbus_register_frontend(struct xenbus_driver *drv,
+ struct module *owner, const char *mod_name)
+{
+ int ret;
+
+ drv->read_otherend_details = read_backend_details;
+
+ ret = xenbus_register_driver_common(drv, &xenbus_frontend,
+ owner, mod_name);
+ if (ret)
+ return ret;
+
+ /* If this driver is loaded as a module wait for devices to attach. */
+ wait_for_devices(drv);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(__xenbus_register_frontend);
+
+static int frontend_probe_and_watch(struct notifier_block *notifier,
+ unsigned long event,
+ void *data)
+{
+ /* Enumerate devices in xenstore and watch for changes. */
+ xenbus_probe_devices(&xenbus_frontend);
+ register_xenbus_watch(&fe_watch);
+
+ return NOTIFY_DONE;
+}
+
+
+static int __init xenbus_probe_frontend_init(void)
+{
+ static struct notifier_block xenstore_notifier = {
+ .notifier_call = frontend_probe_and_watch
+ };
+ int err;
+
+ DPRINTK("");
+
+ /* Register ourselves with the kernel bus subsystem */
+ err = bus_register(&xenbus_frontend.bus);
+ if (err)
+ return err;
+
+ register_xenstore_notifier(&xenstore_notifier);
+
+ return 0;
+}
+subsys_initcall(xenbus_probe_frontend_init);
+
+#ifndef MODULE
+static int __init boot_wait_for_devices(void)
+{
+ if (xen_hvm_domain() && !xen_platform_pci_unplug)
+ return -ENODEV;
+
+ ready_to_wait_for_devices = 1;
+ wait_for_devices(NULL);
+ return 0;
+}
+
+late_initcall(boot_wait_for_devices);
+#endif
+
+MODULE_LICENSE("GPL");
diff --git a/drivers/xen/xenbus/xenbus_xs.c b/drivers/xen/xenbus/xenbus_xs.c
new file mode 100644
index 00000000..daee5db4
--- /dev/null
+++ b/drivers/xen/xenbus/xenbus_xs.c
@@ -0,0 +1,907 @@
+/******************************************************************************
+ * xenbus_xs.c
+ *
+ * This is the kernel equivalent of the "xs" library. We don't need everything
+ * and we use xenbus_comms for communication.
+ *
+ * Copyright (C) 2005 Rusty Russell, IBM Corporation
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation; or, when distributed
+ * separately from the Linux kernel or incorporated into other
+ * software packages, subject to the following license:
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this source file (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use, copy, modify,
+ * merge, publish, distribute, sublicense, and/or sell copies of the Software,
+ * and to permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#include <linux/unistd.h>
+#include <linux/errno.h>
+#include <linux/types.h>
+#include <linux/uio.h>
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/err.h>
+#include <linux/slab.h>
+#include <linux/fcntl.h>
+#include <linux/kthread.h>
+#include <linux/rwsem.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <xen/xenbus.h>
+#include "xenbus_comms.h"
+
+struct xs_stored_msg {
+ struct list_head list;
+
+ struct xsd_sockmsg hdr;
+
+ union {
+ /* Queued replies. */
+ struct {
+ char *body;
+ } reply;
+
+ /* Queued watch events. */
+ struct {
+ struct xenbus_watch *handle;
+ char **vec;
+ unsigned int vec_size;
+ } watch;
+ } u;
+};
+
+struct xs_handle {
+ /* A list of replies. Currently only one will ever be outstanding. */
+ struct list_head reply_list;
+ spinlock_t reply_lock;
+ wait_queue_head_t reply_waitq;
+
+ /*
+ * Mutex ordering: transaction_mutex -> watch_mutex -> request_mutex.
+ * response_mutex is never taken simultaneously with the other three.
+ *
+ * transaction_mutex must be held before incrementing
+ * transaction_count. The mutex is held when a suspend is in
+ * progress to prevent new transactions starting.
+ *
+ * When decrementing transaction_count to zero the wait queue
+ * should be woken up, the suspend code waits for count to
+ * reach zero.
+ */
+
+ /* One request at a time. */
+ struct mutex request_mutex;
+
+ /* Protect xenbus reader thread against save/restore. */
+ struct mutex response_mutex;
+
+ /* Protect transactions against save/restore. */
+ struct mutex transaction_mutex;
+ atomic_t transaction_count;
+ wait_queue_head_t transaction_wq;
+
+ /* Protect watch (de)register against save/restore. */
+ struct rw_semaphore watch_mutex;
+};
+
+static struct xs_handle xs_state;
+
+/* List of registered watches, and a lock to protect it. */
+static LIST_HEAD(watches);
+static DEFINE_SPINLOCK(watches_lock);
+
+/* List of pending watch callback events, and a lock to protect it. */
+static LIST_HEAD(watch_events);
+static DEFINE_SPINLOCK(watch_events_lock);
+
+/*
+ * Details of the xenwatch callback kernel thread. The thread waits on the
+ * watch_events_waitq for work to do (queued on watch_events list). When it
+ * wakes up it acquires the xenwatch_mutex before reading the list and
+ * carrying out work.
+ */
+static pid_t xenwatch_pid;
+static DEFINE_MUTEX(xenwatch_mutex);
+static DECLARE_WAIT_QUEUE_HEAD(watch_events_waitq);
+
+static int get_error(const char *errorstring)
+{
+ unsigned int i;
+
+ for (i = 0; strcmp(errorstring, xsd_errors[i].errstring) != 0; i++) {
+ if (i == ARRAY_SIZE(xsd_errors) - 1) {
+ printk(KERN_WARNING
+ "XENBUS xen store gave: unknown error %s",
+ errorstring);
+ return EINVAL;
+ }
+ }
+ return xsd_errors[i].errnum;
+}
+
+static void *read_reply(enum xsd_sockmsg_type *type, unsigned int *len)
+{
+ struct xs_stored_msg *msg;
+ char *body;
+
+ spin_lock(&xs_state.reply_lock);
+
+ while (list_empty(&xs_state.reply_list)) {
+ spin_unlock(&xs_state.reply_lock);
+ /* XXX FIXME: Avoid synchronous wait for response here. */
+ wait_event(xs_state.reply_waitq,
+ !list_empty(&xs_state.reply_list));
+ spin_lock(&xs_state.reply_lock);
+ }
+
+ msg = list_entry(xs_state.reply_list.next,
+ struct xs_stored_msg, list);
+ list_del(&msg->list);
+
+ spin_unlock(&xs_state.reply_lock);
+
+ *type = msg->hdr.type;
+ if (len)
+ *len = msg->hdr.len;
+ body = msg->u.reply.body;
+
+ kfree(msg);
+
+ return body;
+}
+
+static void transaction_start(void)
+{
+ mutex_lock(&xs_state.transaction_mutex);
+ atomic_inc(&xs_state.transaction_count);
+ mutex_unlock(&xs_state.transaction_mutex);
+}
+
+static void transaction_end(void)
+{
+ if (atomic_dec_and_test(&xs_state.transaction_count))
+ wake_up(&xs_state.transaction_wq);
+}
+
+static void transaction_suspend(void)
+{
+ mutex_lock(&xs_state.transaction_mutex);
+ wait_event(xs_state.transaction_wq,
+ atomic_read(&xs_state.transaction_count) == 0);
+}
+
+static void transaction_resume(void)
+{
+ mutex_unlock(&xs_state.transaction_mutex);
+}
+
+void *xenbus_dev_request_and_reply(struct xsd_sockmsg *msg)
+{
+ void *ret;
+ struct xsd_sockmsg req_msg = *msg;
+ int err;
+
+ if (req_msg.type == XS_TRANSACTION_START)
+ transaction_start();
+
+ mutex_lock(&xs_state.request_mutex);
+
+ err = xb_write(msg, sizeof(*msg) + msg->len);
+ if (err) {
+ msg->type = XS_ERROR;
+ ret = ERR_PTR(err);
+ } else
+ ret = read_reply(&msg->type, &msg->len);
+
+ mutex_unlock(&xs_state.request_mutex);
+
+ if ((msg->type == XS_TRANSACTION_END) ||
+ ((req_msg.type == XS_TRANSACTION_START) &&
+ (msg->type == XS_ERROR)))
+ transaction_end();
+
+ return ret;
+}
+EXPORT_SYMBOL(xenbus_dev_request_and_reply);
+
+/* Send message to xs, get kmalloc'ed reply. ERR_PTR() on error. */
+static void *xs_talkv(struct xenbus_transaction t,
+ enum xsd_sockmsg_type type,
+ const struct kvec *iovec,
+ unsigned int num_vecs,
+ unsigned int *len)
+{
+ struct xsd_sockmsg msg;
+ void *ret = NULL;
+ unsigned int i;
+ int err;
+
+ msg.tx_id = t.id;
+ msg.req_id = 0;
+ msg.type = type;
+ msg.len = 0;
+ for (i = 0; i < num_vecs; i++)
+ msg.len += iovec[i].iov_len;
+
+ mutex_lock(&xs_state.request_mutex);
+
+ err = xb_write(&msg, sizeof(msg));
+ if (err) {
+ mutex_unlock(&xs_state.request_mutex);
+ return ERR_PTR(err);
+ }
+
+ for (i = 0; i < num_vecs; i++) {
+ err = xb_write(iovec[i].iov_base, iovec[i].iov_len);
+ if (err) {
+ mutex_unlock(&xs_state.request_mutex);
+ return ERR_PTR(err);
+ }
+ }
+
+ ret = read_reply(&msg.type, len);
+
+ mutex_unlock(&xs_state.request_mutex);
+
+ if (IS_ERR(ret))
+ return ret;
+
+ if (msg.type == XS_ERROR) {
+ err = get_error(ret);
+ kfree(ret);
+ return ERR_PTR(-err);
+ }
+
+ if (msg.type != type) {
+ if (printk_ratelimit())
+ printk(KERN_WARNING
+ "XENBUS unexpected type [%d], expected [%d]\n",
+ msg.type, type);
+ kfree(ret);
+ return ERR_PTR(-EINVAL);
+ }
+ return ret;
+}
+
+/* Simplified version of xs_talkv: single message. */
+static void *xs_single(struct xenbus_transaction t,
+ enum xsd_sockmsg_type type,
+ const char *string,
+ unsigned int *len)
+{
+ struct kvec iovec;
+
+ iovec.iov_base = (void *)string;
+ iovec.iov_len = strlen(string) + 1;
+ return xs_talkv(t, type, &iovec, 1, len);
+}
+
+/* Many commands only need an ack, don't care what it says. */
+static int xs_error(char *reply)
+{
+ if (IS_ERR(reply))
+ return PTR_ERR(reply);
+ kfree(reply);
+ return 0;
+}
+
+static unsigned int count_strings(const char *strings, unsigned int len)
+{
+ unsigned int num;
+ const char *p;
+
+ for (p = strings, num = 0; p < strings + len; p += strlen(p) + 1)
+ num++;
+
+ return num;
+}
+
+/* Return the path to dir with /name appended. Buffer must be kfree()'ed. */
+static char *join(const char *dir, const char *name)
+{
+ char *buffer;
+
+ if (strlen(name) == 0)
+ buffer = kasprintf(GFP_NOIO | __GFP_HIGH, "%s", dir);
+ else
+ buffer = kasprintf(GFP_NOIO | __GFP_HIGH, "%s/%s", dir, name);
+ return (!buffer) ? ERR_PTR(-ENOMEM) : buffer;
+}
+
+static char **split(char *strings, unsigned int len, unsigned int *num)
+{
+ char *p, **ret;
+
+ /* Count the strings. */
+ *num = count_strings(strings, len);
+
+ /* Transfer to one big alloc for easy freeing. */
+ ret = kmalloc(*num * sizeof(char *) + len, GFP_NOIO | __GFP_HIGH);
+ if (!ret) {
+ kfree(strings);
+ return ERR_PTR(-ENOMEM);
+ }
+ memcpy(&ret[*num], strings, len);
+ kfree(strings);
+
+ strings = (char *)&ret[*num];
+ for (p = strings, *num = 0; p < strings + len; p += strlen(p) + 1)
+ ret[(*num)++] = p;
+
+ return ret;
+}
+
+char **xenbus_directory(struct xenbus_transaction t,
+ const char *dir, const char *node, unsigned int *num)
+{
+ char *strings, *path;
+ unsigned int len;
+
+ path = join(dir, node);
+ if (IS_ERR(path))
+ return (char **)path;
+
+ strings = xs_single(t, XS_DIRECTORY, path, &len);
+ kfree(path);
+ if (IS_ERR(strings))
+ return (char **)strings;
+
+ return split(strings, len, num);
+}
+EXPORT_SYMBOL_GPL(xenbus_directory);
+
+/* Check if a path exists. Return 1 if it does. */
+int xenbus_exists(struct xenbus_transaction t,
+ const char *dir, const char *node)
+{
+ char **d;
+ int dir_n;
+
+ d = xenbus_directory(t, dir, node, &dir_n);
+ if (IS_ERR(d))
+ return 0;
+ kfree(d);
+ return 1;
+}
+EXPORT_SYMBOL_GPL(xenbus_exists);
+
+/* Get the value of a single file.
+ * Returns a kmalloced value: call free() on it after use.
+ * len indicates length in bytes.
+ */
+void *xenbus_read(struct xenbus_transaction t,
+ const char *dir, const char *node, unsigned int *len)
+{
+ char *path;
+ void *ret;
+
+ path = join(dir, node);
+ if (IS_ERR(path))
+ return (void *)path;
+
+ ret = xs_single(t, XS_READ, path, len);
+ kfree(path);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(xenbus_read);
+
+/* Write the value of a single file.
+ * Returns -err on failure.
+ */
+int xenbus_write(struct xenbus_transaction t,
+ const char *dir, const char *node, const char *string)
+{
+ const char *path;
+ struct kvec iovec[2];
+ int ret;
+
+ path = join(dir, node);
+ if (IS_ERR(path))
+ return PTR_ERR(path);
+
+ iovec[0].iov_base = (void *)path;
+ iovec[0].iov_len = strlen(path) + 1;
+ iovec[1].iov_base = (void *)string;
+ iovec[1].iov_len = strlen(string);
+
+ ret = xs_error(xs_talkv(t, XS_WRITE, iovec, ARRAY_SIZE(iovec), NULL));
+ kfree(path);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(xenbus_write);
+
+/* Create a new directory. */
+int xenbus_mkdir(struct xenbus_transaction t,
+ const char *dir, const char *node)
+{
+ char *path;
+ int ret;
+
+ path = join(dir, node);
+ if (IS_ERR(path))
+ return PTR_ERR(path);
+
+ ret = xs_error(xs_single(t, XS_MKDIR, path, NULL));
+ kfree(path);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(xenbus_mkdir);
+
+/* Destroy a file or directory (directories must be empty). */
+int xenbus_rm(struct xenbus_transaction t, const char *dir, const char *node)
+{
+ char *path;
+ int ret;
+
+ path = join(dir, node);
+ if (IS_ERR(path))
+ return PTR_ERR(path);
+
+ ret = xs_error(xs_single(t, XS_RM, path, NULL));
+ kfree(path);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(xenbus_rm);
+
+/* Start a transaction: changes by others will not be seen during this
+ * transaction, and changes will not be visible to others until end.
+ */
+int xenbus_transaction_start(struct xenbus_transaction *t)
+{
+ char *id_str;
+
+ transaction_start();
+
+ id_str = xs_single(XBT_NIL, XS_TRANSACTION_START, "", NULL);
+ if (IS_ERR(id_str)) {
+ transaction_end();
+ return PTR_ERR(id_str);
+ }
+
+ t->id = simple_strtoul(id_str, NULL, 0);
+ kfree(id_str);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(xenbus_transaction_start);
+
+/* End a transaction.
+ * If abandon is true, transaction is discarded instead of committed.
+ */
+int xenbus_transaction_end(struct xenbus_transaction t, int abort)
+{
+ char abortstr[2];
+ int err;
+
+ if (abort)
+ strcpy(abortstr, "F");
+ else
+ strcpy(abortstr, "T");
+
+ err = xs_error(xs_single(t, XS_TRANSACTION_END, abortstr, NULL));
+
+ transaction_end();
+
+ return err;
+}
+EXPORT_SYMBOL_GPL(xenbus_transaction_end);
+
+/* Single read and scanf: returns -errno or num scanned. */
+int xenbus_scanf(struct xenbus_transaction t,
+ const char *dir, const char *node, const char *fmt, ...)
+{
+ va_list ap;
+ int ret;
+ char *val;
+
+ val = xenbus_read(t, dir, node, NULL);
+ if (IS_ERR(val))
+ return PTR_ERR(val);
+
+ va_start(ap, fmt);
+ ret = vsscanf(val, fmt, ap);
+ va_end(ap);
+ kfree(val);
+ /* Distinctive errno. */
+ if (ret == 0)
+ return -ERANGE;
+ return ret;
+}
+EXPORT_SYMBOL_GPL(xenbus_scanf);
+
+/* Single printf and write: returns -errno or 0. */
+int xenbus_printf(struct xenbus_transaction t,
+ const char *dir, const char *node, const char *fmt, ...)
+{
+ va_list ap;
+ int ret;
+#define PRINTF_BUFFER_SIZE 4096
+ char *printf_buffer;
+
+ printf_buffer = kmalloc(PRINTF_BUFFER_SIZE, GFP_NOIO | __GFP_HIGH);
+ if (printf_buffer == NULL)
+ return -ENOMEM;
+
+ va_start(ap, fmt);
+ ret = vsnprintf(printf_buffer, PRINTF_BUFFER_SIZE, fmt, ap);
+ va_end(ap);
+
+ BUG_ON(ret > PRINTF_BUFFER_SIZE-1);
+ ret = xenbus_write(t, dir, node, printf_buffer);
+
+ kfree(printf_buffer);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(xenbus_printf);
+
+/* Takes tuples of names, scanf-style args, and void **, NULL terminated. */
+int xenbus_gather(struct xenbus_transaction t, const char *dir, ...)
+{
+ va_list ap;
+ const char *name;
+ int ret = 0;
+
+ va_start(ap, dir);
+ while (ret == 0 && (name = va_arg(ap, char *)) != NULL) {
+ const char *fmt = va_arg(ap, char *);
+ void *result = va_arg(ap, void *);
+ char *p;
+
+ p = xenbus_read(t, dir, name, NULL);
+ if (IS_ERR(p)) {
+ ret = PTR_ERR(p);
+ break;
+ }
+ if (fmt) {
+ if (sscanf(p, fmt, result) == 0)
+ ret = -EINVAL;
+ kfree(p);
+ } else
+ *(char **)result = p;
+ }
+ va_end(ap);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(xenbus_gather);
+
+static int xs_watch(const char *path, const char *token)
+{
+ struct kvec iov[2];
+
+ iov[0].iov_base = (void *)path;
+ iov[0].iov_len = strlen(path) + 1;
+ iov[1].iov_base = (void *)token;
+ iov[1].iov_len = strlen(token) + 1;
+
+ return xs_error(xs_talkv(XBT_NIL, XS_WATCH, iov,
+ ARRAY_SIZE(iov), NULL));
+}
+
+static int xs_unwatch(const char *path, const char *token)
+{
+ struct kvec iov[2];
+
+ iov[0].iov_base = (char *)path;
+ iov[0].iov_len = strlen(path) + 1;
+ iov[1].iov_base = (char *)token;
+ iov[1].iov_len = strlen(token) + 1;
+
+ return xs_error(xs_talkv(XBT_NIL, XS_UNWATCH, iov,
+ ARRAY_SIZE(iov), NULL));
+}
+
+static struct xenbus_watch *find_watch(const char *token)
+{
+ struct xenbus_watch *i, *cmp;
+
+ cmp = (void *)simple_strtoul(token, NULL, 16);
+
+ list_for_each_entry(i, &watches, list)
+ if (i == cmp)
+ return i;
+
+ return NULL;
+}
+
+/* Register callback to watch this node. */
+int register_xenbus_watch(struct xenbus_watch *watch)
+{
+ /* Pointer in ascii is the token. */
+ char token[sizeof(watch) * 2 + 1];
+ int err;
+
+ sprintf(token, "%lX", (long)watch);
+
+ down_read(&xs_state.watch_mutex);
+
+ spin_lock(&watches_lock);
+ BUG_ON(find_watch(token));
+ list_add(&watch->list, &watches);
+ spin_unlock(&watches_lock);
+
+ err = xs_watch(watch->node, token);
+
+ /* Ignore errors due to multiple registration. */
+ if ((err != 0) && (err != -EEXIST)) {
+ spin_lock(&watches_lock);
+ list_del(&watch->list);
+ spin_unlock(&watches_lock);
+ }
+
+ up_read(&xs_state.watch_mutex);
+
+ return err;
+}
+EXPORT_SYMBOL_GPL(register_xenbus_watch);
+
+void unregister_xenbus_watch(struct xenbus_watch *watch)
+{
+ struct xs_stored_msg *msg, *tmp;
+ char token[sizeof(watch) * 2 + 1];
+ int err;
+
+ sprintf(token, "%lX", (long)watch);
+
+ down_read(&xs_state.watch_mutex);
+
+ spin_lock(&watches_lock);
+ BUG_ON(!find_watch(token));
+ list_del(&watch->list);
+ spin_unlock(&watches_lock);
+
+ err = xs_unwatch(watch->node, token);
+ if (err)
+ printk(KERN_WARNING
+ "XENBUS Failed to release watch %s: %i\n",
+ watch->node, err);
+
+ up_read(&xs_state.watch_mutex);
+
+ /* Make sure there are no callbacks running currently (unless
+ its us) */
+ if (current->pid != xenwatch_pid)
+ mutex_lock(&xenwatch_mutex);
+
+ /* Cancel pending watch events. */
+ spin_lock(&watch_events_lock);
+ list_for_each_entry_safe(msg, tmp, &watch_events, list) {
+ if (msg->u.watch.handle != watch)
+ continue;
+ list_del(&msg->list);
+ kfree(msg->u.watch.vec);
+ kfree(msg);
+ }
+ spin_unlock(&watch_events_lock);
+
+ if (current->pid != xenwatch_pid)
+ mutex_unlock(&xenwatch_mutex);
+}
+EXPORT_SYMBOL_GPL(unregister_xenbus_watch);
+
+void xs_suspend(void)
+{
+ transaction_suspend();
+ down_write(&xs_state.watch_mutex);
+ mutex_lock(&xs_state.request_mutex);
+ mutex_lock(&xs_state.response_mutex);
+}
+
+void xs_resume(void)
+{
+ struct xenbus_watch *watch;
+ char token[sizeof(watch) * 2 + 1];
+
+ xb_init_comms();
+
+ mutex_unlock(&xs_state.response_mutex);
+ mutex_unlock(&xs_state.request_mutex);
+ transaction_resume();
+
+ /* No need for watches_lock: the watch_mutex is sufficient. */
+ list_for_each_entry(watch, &watches, list) {
+ sprintf(token, "%lX", (long)watch);
+ xs_watch(watch->node, token);
+ }
+
+ up_write(&xs_state.watch_mutex);
+}
+
+void xs_suspend_cancel(void)
+{
+ mutex_unlock(&xs_state.response_mutex);
+ mutex_unlock(&xs_state.request_mutex);
+ up_write(&xs_state.watch_mutex);
+ mutex_unlock(&xs_state.transaction_mutex);
+}
+
+static int xenwatch_thread(void *unused)
+{
+ struct list_head *ent;
+ struct xs_stored_msg *msg;
+
+ for (;;) {
+ wait_event_interruptible(watch_events_waitq,
+ !list_empty(&watch_events));
+
+ if (kthread_should_stop())
+ break;
+
+ mutex_lock(&xenwatch_mutex);
+
+ spin_lock(&watch_events_lock);
+ ent = watch_events.next;
+ if (ent != &watch_events)
+ list_del(ent);
+ spin_unlock(&watch_events_lock);
+
+ if (ent != &watch_events) {
+ msg = list_entry(ent, struct xs_stored_msg, list);
+ msg->u.watch.handle->callback(
+ msg->u.watch.handle,
+ (const char **)msg->u.watch.vec,
+ msg->u.watch.vec_size);
+ kfree(msg->u.watch.vec);
+ kfree(msg);
+ }
+
+ mutex_unlock(&xenwatch_mutex);
+ }
+
+ return 0;
+}
+
+static int process_msg(void)
+{
+ struct xs_stored_msg *msg;
+ char *body;
+ int err;
+
+ /*
+ * We must disallow save/restore while reading a xenstore message.
+ * A partial read across s/r leaves us out of sync with xenstored.
+ */
+ for (;;) {
+ err = xb_wait_for_data_to_read();
+ if (err)
+ return err;
+ mutex_lock(&xs_state.response_mutex);
+ if (xb_data_to_read())
+ break;
+ /* We raced with save/restore: pending data 'disappeared'. */
+ mutex_unlock(&xs_state.response_mutex);
+ }
+
+
+ msg = kmalloc(sizeof(*msg), GFP_NOIO | __GFP_HIGH);
+ if (msg == NULL) {
+ err = -ENOMEM;
+ goto out;
+ }
+
+ err = xb_read(&msg->hdr, sizeof(msg->hdr));
+ if (err) {
+ kfree(msg);
+ goto out;
+ }
+
+ if (msg->hdr.len > XENSTORE_PAYLOAD_MAX) {
+ kfree(msg);
+ err = -EINVAL;
+ goto out;
+ }
+
+ body = kmalloc(msg->hdr.len + 1, GFP_NOIO | __GFP_HIGH);
+ if (body == NULL) {
+ kfree(msg);
+ err = -ENOMEM;
+ goto out;
+ }
+
+ err = xb_read(body, msg->hdr.len);
+ if (err) {
+ kfree(body);
+ kfree(msg);
+ goto out;
+ }
+ body[msg->hdr.len] = '\0';
+
+ if (msg->hdr.type == XS_WATCH_EVENT) {
+ msg->u.watch.vec = split(body, msg->hdr.len,
+ &msg->u.watch.vec_size);
+ if (IS_ERR(msg->u.watch.vec)) {
+ err = PTR_ERR(msg->u.watch.vec);
+ kfree(msg);
+ goto out;
+ }
+
+ spin_lock(&watches_lock);
+ msg->u.watch.handle = find_watch(
+ msg->u.watch.vec[XS_WATCH_TOKEN]);
+ if (msg->u.watch.handle != NULL) {
+ spin_lock(&watch_events_lock);
+ list_add_tail(&msg->list, &watch_events);
+ wake_up(&watch_events_waitq);
+ spin_unlock(&watch_events_lock);
+ } else {
+ kfree(msg->u.watch.vec);
+ kfree(msg);
+ }
+ spin_unlock(&watches_lock);
+ } else {
+ msg->u.reply.body = body;
+ spin_lock(&xs_state.reply_lock);
+ list_add_tail(&msg->list, &xs_state.reply_list);
+ spin_unlock(&xs_state.reply_lock);
+ wake_up(&xs_state.reply_waitq);
+ }
+
+ out:
+ mutex_unlock(&xs_state.response_mutex);
+ return err;
+}
+
+static int xenbus_thread(void *unused)
+{
+ int err;
+
+ for (;;) {
+ err = process_msg();
+ if (err)
+ printk(KERN_WARNING "XENBUS error %d while reading "
+ "message\n", err);
+ if (kthread_should_stop())
+ break;
+ }
+
+ return 0;
+}
+
+int xs_init(void)
+{
+ int err;
+ struct task_struct *task;
+
+ INIT_LIST_HEAD(&xs_state.reply_list);
+ spin_lock_init(&xs_state.reply_lock);
+ init_waitqueue_head(&xs_state.reply_waitq);
+
+ mutex_init(&xs_state.request_mutex);
+ mutex_init(&xs_state.response_mutex);
+ mutex_init(&xs_state.transaction_mutex);
+ init_rwsem(&xs_state.watch_mutex);
+ atomic_set(&xs_state.transaction_count, 0);
+ init_waitqueue_head(&xs_state.transaction_wq);
+
+ /* Initialize the shared memory rings to talk to xenstored */
+ err = xb_init_comms();
+ if (err)
+ return err;
+
+ task = kthread_run(xenwatch_thread, NULL, "xenwatch");
+ if (IS_ERR(task))
+ return PTR_ERR(task);
+ xenwatch_pid = task->pid;
+
+ task = kthread_run(xenbus_thread, NULL, "xenbus");
+ if (IS_ERR(task))
+ return PTR_ERR(task);
+
+ return 0;
+}
diff --git a/drivers/xen/xencomm.c b/drivers/xen/xencomm.c
new file mode 100644
index 00000000..b91f8ff5
--- /dev/null
+++ b/drivers/xen/xencomm.c
@@ -0,0 +1,217 @@
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ * Copyright (C) IBM Corp. 2006
+ *
+ * Authors: Hollis Blanchard <hollisb@us.ibm.com>
+ */
+
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <asm/page.h>
+#include <xen/xencomm.h>
+#include <xen/interface/xen.h>
+#include <asm/xen/xencomm.h> /* for xencomm_is_phys_contiguous() */
+
+static int xencomm_init(struct xencomm_desc *desc,
+ void *buffer, unsigned long bytes)
+{
+ unsigned long recorded = 0;
+ int i = 0;
+
+ while ((recorded < bytes) && (i < desc->nr_addrs)) {
+ unsigned long vaddr = (unsigned long)buffer + recorded;
+ unsigned long paddr;
+ int offset;
+ int chunksz;
+
+ offset = vaddr % PAGE_SIZE; /* handle partial pages */
+ chunksz = min(PAGE_SIZE - offset, bytes - recorded);
+
+ paddr = xencomm_vtop(vaddr);
+ if (paddr == ~0UL) {
+ printk(KERN_DEBUG "%s: couldn't translate vaddr %lx\n",
+ __func__, vaddr);
+ return -EINVAL;
+ }
+
+ desc->address[i++] = paddr;
+ recorded += chunksz;
+ }
+
+ if (recorded < bytes) {
+ printk(KERN_DEBUG
+ "%s: could only translate %ld of %ld bytes\n",
+ __func__, recorded, bytes);
+ return -ENOSPC;
+ }
+
+ /* mark remaining addresses invalid (just for safety) */
+ while (i < desc->nr_addrs)
+ desc->address[i++] = XENCOMM_INVALID;
+
+ desc->magic = XENCOMM_MAGIC;
+
+ return 0;
+}
+
+static struct xencomm_desc *xencomm_alloc(gfp_t gfp_mask,
+ void *buffer, unsigned long bytes)
+{
+ struct xencomm_desc *desc;
+ unsigned long buffer_ulong = (unsigned long)buffer;
+ unsigned long start = buffer_ulong & PAGE_MASK;
+ unsigned long end = (buffer_ulong + bytes) | ~PAGE_MASK;
+ unsigned long nr_addrs = (end - start + 1) >> PAGE_SHIFT;
+ unsigned long size = sizeof(*desc) +
+ sizeof(desc->address[0]) * nr_addrs;
+
+ /*
+ * slab allocator returns at least sizeof(void*) aligned pointer.
+ * When sizeof(*desc) > sizeof(void*), struct xencomm_desc might
+ * cross page boundary.
+ */
+ if (sizeof(*desc) > sizeof(void *)) {
+ unsigned long order = get_order(size);
+ desc = (struct xencomm_desc *)__get_free_pages(gfp_mask,
+ order);
+ if (desc == NULL)
+ return NULL;
+
+ desc->nr_addrs =
+ ((PAGE_SIZE << order) - sizeof(struct xencomm_desc)) /
+ sizeof(*desc->address);
+ } else {
+ desc = kmalloc(size, gfp_mask);
+ if (desc == NULL)
+ return NULL;
+
+ desc->nr_addrs = nr_addrs;
+ }
+ return desc;
+}
+
+void xencomm_free(struct xencomm_handle *desc)
+{
+ if (desc && !((ulong)desc & XENCOMM_INLINE_FLAG)) {
+ struct xencomm_desc *desc__ = (struct xencomm_desc *)desc;
+ if (sizeof(*desc__) > sizeof(void *)) {
+ unsigned long size = sizeof(*desc__) +
+ sizeof(desc__->address[0]) * desc__->nr_addrs;
+ unsigned long order = get_order(size);
+ free_pages((unsigned long)__va(desc), order);
+ } else
+ kfree(__va(desc));
+ }
+}
+
+static int xencomm_create(void *buffer, unsigned long bytes,
+ struct xencomm_desc **ret, gfp_t gfp_mask)
+{
+ struct xencomm_desc *desc;
+ int rc;
+
+ pr_debug("%s: %p[%ld]\n", __func__, buffer, bytes);
+
+ if (bytes == 0) {
+ /* don't create a descriptor; Xen recognizes NULL. */
+ BUG_ON(buffer != NULL);
+ *ret = NULL;
+ return 0;
+ }
+
+ BUG_ON(buffer == NULL); /* 'bytes' is non-zero */
+
+ desc = xencomm_alloc(gfp_mask, buffer, bytes);
+ if (!desc) {
+ printk(KERN_DEBUG "%s failure\n", "xencomm_alloc");
+ return -ENOMEM;
+ }
+
+ rc = xencomm_init(desc, buffer, bytes);
+ if (rc) {
+ printk(KERN_DEBUG "%s failure: %d\n", "xencomm_init", rc);
+ xencomm_free((struct xencomm_handle *)__pa(desc));
+ return rc;
+ }
+
+ *ret = desc;
+ return 0;
+}
+
+static struct xencomm_handle *xencomm_create_inline(void *ptr)
+{
+ unsigned long paddr;
+
+ BUG_ON(!xencomm_is_phys_contiguous((unsigned long)ptr));
+
+ paddr = (unsigned long)xencomm_pa(ptr);
+ BUG_ON(paddr & XENCOMM_INLINE_FLAG);
+ return (struct xencomm_handle *)(paddr | XENCOMM_INLINE_FLAG);
+}
+
+/* "mini" routine, for stack-based communications: */
+static int xencomm_create_mini(void *buffer,
+ unsigned long bytes, struct xencomm_mini *xc_desc,
+ struct xencomm_desc **ret)
+{
+ int rc = 0;
+ struct xencomm_desc *desc;
+ BUG_ON(((unsigned long)xc_desc) % sizeof(*xc_desc) != 0);
+
+ desc = (void *)xc_desc;
+
+ desc->nr_addrs = XENCOMM_MINI_ADDRS;
+
+ rc = xencomm_init(desc, buffer, bytes);
+ if (!rc)
+ *ret = desc;
+
+ return rc;
+}
+
+struct xencomm_handle *xencomm_map(void *ptr, unsigned long bytes)
+{
+ int rc;
+ struct xencomm_desc *desc;
+
+ if (xencomm_is_phys_contiguous((unsigned long)ptr))
+ return xencomm_create_inline(ptr);
+
+ rc = xencomm_create(ptr, bytes, &desc, GFP_KERNEL);
+
+ if (rc || desc == NULL)
+ return NULL;
+
+ return xencomm_pa(desc);
+}
+
+struct xencomm_handle *__xencomm_map_no_alloc(void *ptr, unsigned long bytes,
+ struct xencomm_mini *xc_desc)
+{
+ int rc;
+ struct xencomm_desc *desc = NULL;
+
+ if (xencomm_is_phys_contiguous((unsigned long)ptr))
+ return xencomm_create_inline(ptr);
+
+ rc = xencomm_create_mini(ptr, bytes, xc_desc,
+ &desc);
+
+ if (rc)
+ return NULL;
+
+ return xencomm_pa(desc);
+}
diff --git a/drivers/xen/xenfs/Makefile b/drivers/xen/xenfs/Makefile
new file mode 100644
index 00000000..4fde9440
--- /dev/null
+++ b/drivers/xen/xenfs/Makefile
@@ -0,0 +1,4 @@
+obj-$(CONFIG_XENFS) += xenfs.o
+
+xenfs-y = super.o xenbus.o privcmd.o
+xenfs-$(CONFIG_XEN_DOM0) += xenstored.o
diff --git a/drivers/xen/xenfs/privcmd.c b/drivers/xen/xenfs/privcmd.c
new file mode 100644
index 00000000..dbd3b16f
--- /dev/null
+++ b/drivers/xen/xenfs/privcmd.c
@@ -0,0 +1,400 @@
+/******************************************************************************
+ * privcmd.c
+ *
+ * Interface to privileged domain-0 commands.
+ *
+ * Copyright (c) 2002-2004, K A Fraser, B Dragovic
+ */
+
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/errno.h>
+#include <linux/mm.h>
+#include <linux/mman.h>
+#include <linux/uaccess.h>
+#include <linux/swap.h>
+#include <linux/highmem.h>
+#include <linux/pagemap.h>
+#include <linux/seq_file.h>
+
+#include <asm/pgalloc.h>
+#include <asm/pgtable.h>
+#include <asm/tlb.h>
+#include <asm/xen/hypervisor.h>
+#include <asm/xen/hypercall.h>
+
+#include <xen/xen.h>
+#include <xen/privcmd.h>
+#include <xen/interface/xen.h>
+#include <xen/features.h>
+#include <xen/page.h>
+#include <xen/xen-ops.h>
+
+#ifndef HAVE_ARCH_PRIVCMD_MMAP
+static int privcmd_enforce_singleshot_mapping(struct vm_area_struct *vma);
+#endif
+
+static long privcmd_ioctl_hypercall(void __user *udata)
+{
+ struct privcmd_hypercall hypercall;
+ long ret;
+
+ if (copy_from_user(&hypercall, udata, sizeof(hypercall)))
+ return -EFAULT;
+
+ ret = privcmd_call(hypercall.op,
+ hypercall.arg[0], hypercall.arg[1],
+ hypercall.arg[2], hypercall.arg[3],
+ hypercall.arg[4]);
+
+ return ret;
+}
+
+static void free_page_list(struct list_head *pages)
+{
+ struct page *p, *n;
+
+ list_for_each_entry_safe(p, n, pages, lru)
+ __free_page(p);
+
+ INIT_LIST_HEAD(pages);
+}
+
+/*
+ * Given an array of items in userspace, return a list of pages
+ * containing the data. If copying fails, either because of memory
+ * allocation failure or a problem reading user memory, return an
+ * error code; its up to the caller to dispose of any partial list.
+ */
+static int gather_array(struct list_head *pagelist,
+ unsigned nelem, size_t size,
+ void __user *data)
+{
+ unsigned pageidx;
+ void *pagedata;
+ int ret;
+
+ if (size > PAGE_SIZE)
+ return 0;
+
+ pageidx = PAGE_SIZE;
+ pagedata = NULL; /* quiet, gcc */
+ while (nelem--) {
+ if (pageidx > PAGE_SIZE-size) {
+ struct page *page = alloc_page(GFP_KERNEL);
+
+ ret = -ENOMEM;
+ if (page == NULL)
+ goto fail;
+
+ pagedata = page_address(page);
+
+ list_add_tail(&page->lru, pagelist);
+ pageidx = 0;
+ }
+
+ ret = -EFAULT;
+ if (copy_from_user(pagedata + pageidx, data, size))
+ goto fail;
+
+ data += size;
+ pageidx += size;
+ }
+
+ ret = 0;
+
+fail:
+ return ret;
+}
+
+/*
+ * Call function "fn" on each element of the array fragmented
+ * over a list of pages.
+ */
+static int traverse_pages(unsigned nelem, size_t size,
+ struct list_head *pos,
+ int (*fn)(void *data, void *state),
+ void *state)
+{
+ void *pagedata;
+ unsigned pageidx;
+ int ret = 0;
+
+ BUG_ON(size > PAGE_SIZE);
+
+ pageidx = PAGE_SIZE;
+ pagedata = NULL; /* hush, gcc */
+
+ while (nelem--) {
+ if (pageidx > PAGE_SIZE-size) {
+ struct page *page;
+ pos = pos->next;
+ page = list_entry(pos, struct page, lru);
+ pagedata = page_address(page);
+ pageidx = 0;
+ }
+
+ ret = (*fn)(pagedata + pageidx, state);
+ if (ret)
+ break;
+ pageidx += size;
+ }
+
+ return ret;
+}
+
+struct mmap_mfn_state {
+ unsigned long va;
+ struct vm_area_struct *vma;
+ domid_t domain;
+};
+
+static int mmap_mfn_range(void *data, void *state)
+{
+ struct privcmd_mmap_entry *msg = data;
+ struct mmap_mfn_state *st = state;
+ struct vm_area_struct *vma = st->vma;
+ int rc;
+
+ /* Do not allow range to wrap the address space. */
+ if ((msg->npages > (LONG_MAX >> PAGE_SHIFT)) ||
+ ((unsigned long)(msg->npages << PAGE_SHIFT) >= -st->va))
+ return -EINVAL;
+
+ /* Range chunks must be contiguous in va space. */
+ if ((msg->va != st->va) ||
+ ((msg->va+(msg->npages<<PAGE_SHIFT)) > vma->vm_end))
+ return -EINVAL;
+
+ rc = xen_remap_domain_mfn_range(vma,
+ msg->va & PAGE_MASK,
+ msg->mfn, msg->npages,
+ vma->vm_page_prot,
+ st->domain);
+ if (rc < 0)
+ return rc;
+
+ st->va += msg->npages << PAGE_SHIFT;
+
+ return 0;
+}
+
+static long privcmd_ioctl_mmap(void __user *udata)
+{
+ struct privcmd_mmap mmapcmd;
+ struct mm_struct *mm = current->mm;
+ struct vm_area_struct *vma;
+ int rc;
+ LIST_HEAD(pagelist);
+ struct mmap_mfn_state state;
+
+ if (!xen_initial_domain())
+ return -EPERM;
+
+ if (copy_from_user(&mmapcmd, udata, sizeof(mmapcmd)))
+ return -EFAULT;
+
+ rc = gather_array(&pagelist,
+ mmapcmd.num, sizeof(struct privcmd_mmap_entry),
+ mmapcmd.entry);
+
+ if (rc || list_empty(&pagelist))
+ goto out;
+
+ down_write(&mm->mmap_sem);
+
+ {
+ struct page *page = list_first_entry(&pagelist,
+ struct page, lru);
+ struct privcmd_mmap_entry *msg = page_address(page);
+
+ vma = find_vma(mm, msg->va);
+ rc = -EINVAL;
+
+ if (!vma || (msg->va != vma->vm_start) ||
+ !privcmd_enforce_singleshot_mapping(vma))
+ goto out_up;
+ }
+
+ state.va = vma->vm_start;
+ state.vma = vma;
+ state.domain = mmapcmd.dom;
+
+ rc = traverse_pages(mmapcmd.num, sizeof(struct privcmd_mmap_entry),
+ &pagelist,
+ mmap_mfn_range, &state);
+
+
+out_up:
+ up_write(&mm->mmap_sem);
+
+out:
+ free_page_list(&pagelist);
+
+ return rc;
+}
+
+struct mmap_batch_state {
+ domid_t domain;
+ unsigned long va;
+ struct vm_area_struct *vma;
+ int err;
+
+ xen_pfn_t __user *user;
+};
+
+static int mmap_batch_fn(void *data, void *state)
+{
+ xen_pfn_t *mfnp = data;
+ struct mmap_batch_state *st = state;
+
+ if (xen_remap_domain_mfn_range(st->vma, st->va & PAGE_MASK, *mfnp, 1,
+ st->vma->vm_page_prot, st->domain) < 0) {
+ *mfnp |= 0xf0000000U;
+ st->err++;
+ }
+ st->va += PAGE_SIZE;
+
+ return 0;
+}
+
+static int mmap_return_errors(void *data, void *state)
+{
+ xen_pfn_t *mfnp = data;
+ struct mmap_batch_state *st = state;
+
+ return put_user(*mfnp, st->user++);
+}
+
+static struct vm_operations_struct privcmd_vm_ops;
+
+static long privcmd_ioctl_mmap_batch(void __user *udata)
+{
+ int ret;
+ struct privcmd_mmapbatch m;
+ struct mm_struct *mm = current->mm;
+ struct vm_area_struct *vma;
+ unsigned long nr_pages;
+ LIST_HEAD(pagelist);
+ struct mmap_batch_state state;
+
+ if (!xen_initial_domain())
+ return -EPERM;
+
+ if (copy_from_user(&m, udata, sizeof(m)))
+ return -EFAULT;
+
+ nr_pages = m.num;
+ if ((m.num <= 0) || (nr_pages > (LONG_MAX >> PAGE_SHIFT)))
+ return -EINVAL;
+
+ ret = gather_array(&pagelist, m.num, sizeof(xen_pfn_t),
+ m.arr);
+
+ if (ret || list_empty(&pagelist))
+ goto out;
+
+ down_write(&mm->mmap_sem);
+
+ vma = find_vma(mm, m.addr);
+ ret = -EINVAL;
+ if (!vma ||
+ vma->vm_ops != &privcmd_vm_ops ||
+ (m.addr != vma->vm_start) ||
+ ((m.addr + (nr_pages << PAGE_SHIFT)) != vma->vm_end) ||
+ !privcmd_enforce_singleshot_mapping(vma)) {
+ up_write(&mm->mmap_sem);
+ goto out;
+ }
+
+ state.domain = m.dom;
+ state.vma = vma;
+ state.va = m.addr;
+ state.err = 0;
+
+ ret = traverse_pages(m.num, sizeof(xen_pfn_t),
+ &pagelist, mmap_batch_fn, &state);
+
+ up_write(&mm->mmap_sem);
+
+ if (state.err > 0) {
+ state.user = m.arr;
+ ret = traverse_pages(m.num, sizeof(xen_pfn_t),
+ &pagelist,
+ mmap_return_errors, &state);
+ }
+
+out:
+ free_page_list(&pagelist);
+
+ return ret;
+}
+
+static long privcmd_ioctl(struct file *file,
+ unsigned int cmd, unsigned long data)
+{
+ int ret = -ENOSYS;
+ void __user *udata = (void __user *) data;
+
+ switch (cmd) {
+ case IOCTL_PRIVCMD_HYPERCALL:
+ ret = privcmd_ioctl_hypercall(udata);
+ break;
+
+ case IOCTL_PRIVCMD_MMAP:
+ ret = privcmd_ioctl_mmap(udata);
+ break;
+
+ case IOCTL_PRIVCMD_MMAPBATCH:
+ ret = privcmd_ioctl_mmap_batch(udata);
+ break;
+
+ default:
+ ret = -EINVAL;
+ break;
+ }
+
+ return ret;
+}
+
+#ifndef HAVE_ARCH_PRIVCMD_MMAP
+static int privcmd_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
+{
+ printk(KERN_DEBUG "privcmd_fault: vma=%p %lx-%lx, pgoff=%lx, uv=%p\n",
+ vma, vma->vm_start, vma->vm_end,
+ vmf->pgoff, vmf->virtual_address);
+
+ return VM_FAULT_SIGBUS;
+}
+
+static struct vm_operations_struct privcmd_vm_ops = {
+ .fault = privcmd_fault
+};
+
+static int privcmd_mmap(struct file *file, struct vm_area_struct *vma)
+{
+ /* Unsupported for auto-translate guests. */
+ if (xen_feature(XENFEAT_auto_translated_physmap))
+ return -ENOSYS;
+
+ /* DONTCOPY is essential for Xen because copy_page_range doesn't know
+ * how to recreate these mappings */
+ vma->vm_flags |= VM_RESERVED | VM_IO | VM_DONTCOPY | VM_PFNMAP;
+ vma->vm_ops = &privcmd_vm_ops;
+ vma->vm_private_data = NULL;
+
+ return 0;
+}
+
+static int privcmd_enforce_singleshot_mapping(struct vm_area_struct *vma)
+{
+ return (xchg(&vma->vm_private_data, (void *)1) == NULL);
+}
+#endif
+
+const struct file_operations privcmd_file_ops = {
+ .unlocked_ioctl = privcmd_ioctl,
+ .mmap = privcmd_mmap,
+};
diff --git a/drivers/xen/xenfs/super.c b/drivers/xen/xenfs/super.c
new file mode 100644
index 00000000..1aa38971
--- /dev/null
+++ b/drivers/xen/xenfs/super.c
@@ -0,0 +1,137 @@
+/*
+ * xenfs.c - a filesystem for passing info between the a domain and
+ * the hypervisor.
+ *
+ * 2008-10-07 Alex Zeffertt Replaced /proc/xen/xenbus with xenfs filesystem
+ * and /proc/xen compatibility mount point.
+ * Turned xenfs into a loadable module.
+ */
+
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/module.h>
+#include <linux/fs.h>
+#include <linux/magic.h>
+
+#include <xen/xen.h>
+
+#include "xenfs.h"
+
+#include <asm/xen/hypervisor.h>
+
+MODULE_DESCRIPTION("Xen filesystem");
+MODULE_LICENSE("GPL");
+
+static struct inode *xenfs_make_inode(struct super_block *sb, int mode)
+{
+ struct inode *ret = new_inode(sb);
+
+ if (ret) {
+ ret->i_mode = mode;
+ ret->i_uid = ret->i_gid = 0;
+ ret->i_blocks = 0;
+ ret->i_atime = ret->i_mtime = ret->i_ctime = CURRENT_TIME;
+ }
+ return ret;
+}
+
+static struct dentry *xenfs_create_file(struct super_block *sb,
+ struct dentry *parent,
+ const char *name,
+ const struct file_operations *fops,
+ void *data,
+ int mode)
+{
+ struct dentry *dentry;
+ struct inode *inode;
+
+ dentry = d_alloc_name(parent, name);
+ if (!dentry)
+ return NULL;
+
+ inode = xenfs_make_inode(sb, S_IFREG | mode);
+ if (!inode) {
+ dput(dentry);
+ return NULL;
+ }
+
+ inode->i_fop = fops;
+ inode->i_private = data;
+
+ d_add(dentry, inode);
+ return dentry;
+}
+
+static ssize_t capabilities_read(struct file *file, char __user *buf,
+ size_t size, loff_t *off)
+{
+ char *tmp = "";
+
+ if (xen_initial_domain())
+ tmp = "control_d\n";
+
+ return simple_read_from_buffer(buf, size, off, tmp, strlen(tmp));
+}
+
+static const struct file_operations capabilities_file_ops = {
+ .read = capabilities_read,
+ .llseek = default_llseek,
+};
+
+static int xenfs_fill_super(struct super_block *sb, void *data, int silent)
+{
+ static struct tree_descr xenfs_files[] = {
+ [1] = {},
+ { "xenbus", &xenbus_file_ops, S_IRUSR|S_IWUSR },
+ { "capabilities", &capabilities_file_ops, S_IRUGO },
+ { "privcmd", &privcmd_file_ops, S_IRUSR|S_IWUSR },
+ {""},
+ };
+ int rc;
+
+ rc = simple_fill_super(sb, XENFS_SUPER_MAGIC, xenfs_files);
+ if (rc < 0)
+ return rc;
+
+ if (xen_initial_domain()) {
+ xenfs_create_file(sb, sb->s_root, "xsd_kva",
+ &xsd_kva_file_ops, NULL, S_IRUSR|S_IWUSR);
+ xenfs_create_file(sb, sb->s_root, "xsd_port",
+ &xsd_port_file_ops, NULL, S_IRUSR|S_IWUSR);
+ }
+
+ return rc;
+}
+
+static struct dentry *xenfs_mount(struct file_system_type *fs_type,
+ int flags, const char *dev_name,
+ void *data)
+{
+ return mount_single(fs_type, flags, data, xenfs_fill_super);
+}
+
+static struct file_system_type xenfs_type = {
+ .owner = THIS_MODULE,
+ .name = "xenfs",
+ .mount = xenfs_mount,
+ .kill_sb = kill_litter_super,
+};
+
+static int __init xenfs_init(void)
+{
+ if (xen_domain())
+ return register_filesystem(&xenfs_type);
+
+ printk(KERN_INFO "XENFS: not registering filesystem on non-xen platform\n");
+ return 0;
+}
+
+static void __exit xenfs_exit(void)
+{
+ if (xen_domain())
+ unregister_filesystem(&xenfs_type);
+}
+
+module_init(xenfs_init);
+module_exit(xenfs_exit);
+
diff --git a/drivers/xen/xenfs/xenbus.c b/drivers/xen/xenfs/xenbus.c
new file mode 100644
index 00000000..bbd000f8
--- /dev/null
+++ b/drivers/xen/xenfs/xenbus.c
@@ -0,0 +1,593 @@
+/*
+ * Driver giving user-space access to the kernel's xenbus connection
+ * to xenstore.
+ *
+ * Copyright (c) 2005, Christian Limpach
+ * Copyright (c) 2005, Rusty Russell, IBM Corporation
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation; or, when distributed
+ * separately from the Linux kernel or incorporated into other
+ * software packages, subject to the following license:
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this source file (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use, copy, modify,
+ * merge, publish, distribute, sublicense, and/or sell copies of the Software,
+ * and to permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ *
+ * Changes:
+ * 2008-10-07 Alex Zeffertt Replaced /proc/xen/xenbus with xenfs filesystem
+ * and /proc/xen compatibility mount point.
+ * Turned xenfs into a loadable module.
+ */
+
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/uio.h>
+#include <linux/notifier.h>
+#include <linux/wait.h>
+#include <linux/fs.h>
+#include <linux/poll.h>
+#include <linux/mutex.h>
+#include <linux/sched.h>
+#include <linux/spinlock.h>
+#include <linux/mount.h>
+#include <linux/pagemap.h>
+#include <linux/uaccess.h>
+#include <linux/init.h>
+#include <linux/namei.h>
+#include <linux/string.h>
+#include <linux/slab.h>
+
+#include "xenfs.h"
+#include "../xenbus/xenbus_comms.h"
+
+#include <xen/xenbus.h>
+#include <asm/xen/hypervisor.h>
+
+/*
+ * An element of a list of outstanding transactions, for which we're
+ * still waiting a reply.
+ */
+struct xenbus_transaction_holder {
+ struct list_head list;
+ struct xenbus_transaction handle;
+};
+
+/*
+ * A buffer of data on the queue.
+ */
+struct read_buffer {
+ struct list_head list;
+ unsigned int cons;
+ unsigned int len;
+ char msg[];
+};
+
+struct xenbus_file_priv {
+ /*
+ * msgbuffer_mutex is held while partial requests are built up
+ * and complete requests are acted on. It therefore protects
+ * the "transactions" and "watches" lists, and the partial
+ * request length and buffer.
+ *
+ * reply_mutex protects the reply being built up to return to
+ * usermode. It nests inside msgbuffer_mutex but may be held
+ * alone during a watch callback.
+ */
+ struct mutex msgbuffer_mutex;
+
+ /* In-progress transactions */
+ struct list_head transactions;
+
+ /* Active watches. */
+ struct list_head watches;
+
+ /* Partial request. */
+ unsigned int len;
+ union {
+ struct xsd_sockmsg msg;
+ char buffer[PAGE_SIZE];
+ } u;
+
+ /* Response queue. */
+ struct mutex reply_mutex;
+ struct list_head read_buffers;
+ wait_queue_head_t read_waitq;
+
+};
+
+/* Read out any raw xenbus messages queued up. */
+static ssize_t xenbus_file_read(struct file *filp,
+ char __user *ubuf,
+ size_t len, loff_t *ppos)
+{
+ struct xenbus_file_priv *u = filp->private_data;
+ struct read_buffer *rb;
+ unsigned i;
+ int ret;
+
+ mutex_lock(&u->reply_mutex);
+again:
+ while (list_empty(&u->read_buffers)) {
+ mutex_unlock(&u->reply_mutex);
+ if (filp->f_flags & O_NONBLOCK)
+ return -EAGAIN;
+
+ ret = wait_event_interruptible(u->read_waitq,
+ !list_empty(&u->read_buffers));
+ if (ret)
+ return ret;
+ mutex_lock(&u->reply_mutex);
+ }
+
+ rb = list_entry(u->read_buffers.next, struct read_buffer, list);
+ i = 0;
+ while (i < len) {
+ unsigned sz = min((unsigned)len - i, rb->len - rb->cons);
+
+ ret = copy_to_user(ubuf + i, &rb->msg[rb->cons], sz);
+
+ i += sz - ret;
+ rb->cons += sz - ret;
+
+ if (ret != 0) {
+ if (i == 0)
+ i = -EFAULT;
+ goto out;
+ }
+
+ /* Clear out buffer if it has been consumed */
+ if (rb->cons == rb->len) {
+ list_del(&rb->list);
+ kfree(rb);
+ if (list_empty(&u->read_buffers))
+ break;
+ rb = list_entry(u->read_buffers.next,
+ struct read_buffer, list);
+ }
+ }
+ if (i == 0)
+ goto again;
+
+out:
+ mutex_unlock(&u->reply_mutex);
+ return i;
+}
+
+/*
+ * Add a buffer to the queue. Caller must hold the appropriate lock
+ * if the queue is not local. (Commonly the caller will build up
+ * multiple queued buffers on a temporary local list, and then add it
+ * to the appropriate list under lock once all the buffers have een
+ * successfully allocated.)
+ */
+static int queue_reply(struct list_head *queue, const void *data, size_t len)
+{
+ struct read_buffer *rb;
+
+ if (len == 0)
+ return 0;
+
+ rb = kmalloc(sizeof(*rb) + len, GFP_KERNEL);
+ if (rb == NULL)
+ return -ENOMEM;
+
+ rb->cons = 0;
+ rb->len = len;
+
+ memcpy(rb->msg, data, len);
+
+ list_add_tail(&rb->list, queue);
+ return 0;
+}
+
+/*
+ * Free all the read_buffer s on a list.
+ * Caller must have sole reference to list.
+ */
+static void queue_cleanup(struct list_head *list)
+{
+ struct read_buffer *rb;
+
+ while (!list_empty(list)) {
+ rb = list_entry(list->next, struct read_buffer, list);
+ list_del(list->next);
+ kfree(rb);
+ }
+}
+
+struct watch_adapter {
+ struct list_head list;
+ struct xenbus_watch watch;
+ struct xenbus_file_priv *dev_data;
+ char *token;
+};
+
+static void free_watch_adapter(struct watch_adapter *watch)
+{
+ kfree(watch->watch.node);
+ kfree(watch->token);
+ kfree(watch);
+}
+
+static struct watch_adapter *alloc_watch_adapter(const char *path,
+ const char *token)
+{
+ struct watch_adapter *watch;
+
+ watch = kzalloc(sizeof(*watch), GFP_KERNEL);
+ if (watch == NULL)
+ goto out_fail;
+
+ watch->watch.node = kstrdup(path, GFP_KERNEL);
+ if (watch->watch.node == NULL)
+ goto out_free;
+
+ watch->token = kstrdup(token, GFP_KERNEL);
+ if (watch->token == NULL)
+ goto out_free;
+
+ return watch;
+
+out_free:
+ free_watch_adapter(watch);
+
+out_fail:
+ return NULL;
+}
+
+static void watch_fired(struct xenbus_watch *watch,
+ const char **vec,
+ unsigned int len)
+{
+ struct watch_adapter *adap;
+ struct xsd_sockmsg hdr;
+ const char *path, *token;
+ int path_len, tok_len, body_len, data_len = 0;
+ int ret;
+ LIST_HEAD(staging_q);
+
+ adap = container_of(watch, struct watch_adapter, watch);
+
+ path = vec[XS_WATCH_PATH];
+ token = adap->token;
+
+ path_len = strlen(path) + 1;
+ tok_len = strlen(token) + 1;
+ if (len > 2)
+ data_len = vec[len] - vec[2] + 1;
+ body_len = path_len + tok_len + data_len;
+
+ hdr.type = XS_WATCH_EVENT;
+ hdr.len = body_len;
+
+ mutex_lock(&adap->dev_data->reply_mutex);
+
+ ret = queue_reply(&staging_q, &hdr, sizeof(hdr));
+ if (!ret)
+ ret = queue_reply(&staging_q, path, path_len);
+ if (!ret)
+ ret = queue_reply(&staging_q, token, tok_len);
+ if (!ret && len > 2)
+ ret = queue_reply(&staging_q, vec[2], data_len);
+
+ if (!ret) {
+ /* success: pass reply list onto watcher */
+ list_splice_tail(&staging_q, &adap->dev_data->read_buffers);
+ wake_up(&adap->dev_data->read_waitq);
+ } else
+ queue_cleanup(&staging_q);
+
+ mutex_unlock(&adap->dev_data->reply_mutex);
+}
+
+static int xenbus_write_transaction(unsigned msg_type,
+ struct xenbus_file_priv *u)
+{
+ int rc;
+ void *reply;
+ struct xenbus_transaction_holder *trans = NULL;
+ LIST_HEAD(staging_q);
+
+ if (msg_type == XS_TRANSACTION_START) {
+ trans = kmalloc(sizeof(*trans), GFP_KERNEL);
+ if (!trans) {
+ rc = -ENOMEM;
+ goto out;
+ }
+ }
+
+ reply = xenbus_dev_request_and_reply(&u->u.msg);
+ if (IS_ERR(reply)) {
+ kfree(trans);
+ rc = PTR_ERR(reply);
+ goto out;
+ }
+
+ if (msg_type == XS_TRANSACTION_START) {
+ trans->handle.id = simple_strtoul(reply, NULL, 0);
+
+ list_add(&trans->list, &u->transactions);
+ } else if (msg_type == XS_TRANSACTION_END) {
+ list_for_each_entry(trans, &u->transactions, list)
+ if (trans->handle.id == u->u.msg.tx_id)
+ break;
+ BUG_ON(&trans->list == &u->transactions);
+ list_del(&trans->list);
+
+ kfree(trans);
+ }
+
+ mutex_lock(&u->reply_mutex);
+ rc = queue_reply(&staging_q, &u->u.msg, sizeof(u->u.msg));
+ if (!rc)
+ rc = queue_reply(&staging_q, reply, u->u.msg.len);
+ if (!rc) {
+ list_splice_tail(&staging_q, &u->read_buffers);
+ wake_up(&u->read_waitq);
+ } else {
+ queue_cleanup(&staging_q);
+ }
+ mutex_unlock(&u->reply_mutex);
+
+ kfree(reply);
+
+out:
+ return rc;
+}
+
+static int xenbus_write_watch(unsigned msg_type, struct xenbus_file_priv *u)
+{
+ struct watch_adapter *watch, *tmp_watch;
+ char *path, *token;
+ int err, rc;
+ LIST_HEAD(staging_q);
+
+ path = u->u.buffer + sizeof(u->u.msg);
+ token = memchr(path, 0, u->u.msg.len);
+ if (token == NULL) {
+ rc = -EILSEQ;
+ goto out;
+ }
+ token++;
+
+ if (msg_type == XS_WATCH) {
+ watch = alloc_watch_adapter(path, token);
+ if (watch == NULL) {
+ rc = -ENOMEM;
+ goto out;
+ }
+
+ watch->watch.callback = watch_fired;
+ watch->dev_data = u;
+
+ err = register_xenbus_watch(&watch->watch);
+ if (err) {
+ free_watch_adapter(watch);
+ rc = err;
+ goto out;
+ }
+ list_add(&watch->list, &u->watches);
+ } else {
+ list_for_each_entry_safe(watch, tmp_watch, &u->watches, list) {
+ if (!strcmp(watch->token, token) &&
+ !strcmp(watch->watch.node, path)) {
+ unregister_xenbus_watch(&watch->watch);
+ list_del(&watch->list);
+ free_watch_adapter(watch);
+ break;
+ }
+ }
+ }
+
+ /* Success. Synthesize a reply to say all is OK. */
+ {
+ struct {
+ struct xsd_sockmsg hdr;
+ char body[3];
+ } __packed reply = {
+ {
+ .type = msg_type,
+ .len = sizeof(reply.body)
+ },
+ "OK"
+ };
+
+ mutex_lock(&u->reply_mutex);
+ rc = queue_reply(&u->read_buffers, &reply, sizeof(reply));
+ wake_up(&u->read_waitq);
+ mutex_unlock(&u->reply_mutex);
+ }
+
+out:
+ return rc;
+}
+
+static ssize_t xenbus_file_write(struct file *filp,
+ const char __user *ubuf,
+ size_t len, loff_t *ppos)
+{
+ struct xenbus_file_priv *u = filp->private_data;
+ uint32_t msg_type;
+ int rc = len;
+ int ret;
+ LIST_HEAD(staging_q);
+
+ /*
+ * We're expecting usermode to be writing properly formed
+ * xenbus messages. If they write an incomplete message we
+ * buffer it up. Once it is complete, we act on it.
+ */
+
+ /*
+ * Make sure concurrent writers can't stomp all over each
+ * other's messages and make a mess of our partial message
+ * buffer. We don't make any attemppt to stop multiple
+ * writers from making a mess of each other's incomplete
+ * messages; we're just trying to guarantee our own internal
+ * consistency and make sure that single writes are handled
+ * atomically.
+ */
+ mutex_lock(&u->msgbuffer_mutex);
+
+ /* Get this out of the way early to avoid confusion */
+ if (len == 0)
+ goto out;
+
+ /* Can't write a xenbus message larger we can buffer */
+ if ((len + u->len) > sizeof(u->u.buffer)) {
+ /* On error, dump existing buffer */
+ u->len = 0;
+ rc = -EINVAL;
+ goto out;
+ }
+
+ ret = copy_from_user(u->u.buffer + u->len, ubuf, len);
+
+ if (ret != 0) {
+ rc = -EFAULT;
+ goto out;
+ }
+
+ /* Deal with a partial copy. */
+ len -= ret;
+ rc = len;
+
+ u->len += len;
+
+ /* Return if we haven't got a full message yet */
+ if (u->len < sizeof(u->u.msg))
+ goto out; /* not even the header yet */
+
+ /* If we're expecting a message that's larger than we can
+ possibly send, dump what we have and return an error. */
+ if ((sizeof(u->u.msg) + u->u.msg.len) > sizeof(u->u.buffer)) {
+ rc = -E2BIG;
+ u->len = 0;
+ goto out;
+ }
+
+ if (u->len < (sizeof(u->u.msg) + u->u.msg.len))
+ goto out; /* incomplete data portion */
+
+ /*
+ * OK, now we have a complete message. Do something with it.
+ */
+
+ msg_type = u->u.msg.type;
+
+ switch (msg_type) {
+ case XS_WATCH:
+ case XS_UNWATCH:
+ /* (Un)Ask for some path to be watched for changes */
+ ret = xenbus_write_watch(msg_type, u);
+ break;
+
+ default:
+ /* Send out a transaction */
+ ret = xenbus_write_transaction(msg_type, u);
+ break;
+ }
+ if (ret != 0)
+ rc = ret;
+
+ /* Buffered message consumed */
+ u->len = 0;
+
+ out:
+ mutex_unlock(&u->msgbuffer_mutex);
+ return rc;
+}
+
+static int xenbus_file_open(struct inode *inode, struct file *filp)
+{
+ struct xenbus_file_priv *u;
+
+ if (xen_store_evtchn == 0)
+ return -ENOENT;
+
+ nonseekable_open(inode, filp);
+
+ u = kzalloc(sizeof(*u), GFP_KERNEL);
+ if (u == NULL)
+ return -ENOMEM;
+
+ INIT_LIST_HEAD(&u->transactions);
+ INIT_LIST_HEAD(&u->watches);
+ INIT_LIST_HEAD(&u->read_buffers);
+ init_waitqueue_head(&u->read_waitq);
+
+ mutex_init(&u->reply_mutex);
+ mutex_init(&u->msgbuffer_mutex);
+
+ filp->private_data = u;
+
+ return 0;
+}
+
+static int xenbus_file_release(struct inode *inode, struct file *filp)
+{
+ struct xenbus_file_priv *u = filp->private_data;
+ struct xenbus_transaction_holder *trans, *tmp;
+ struct watch_adapter *watch, *tmp_watch;
+ struct read_buffer *rb, *tmp_rb;
+
+ /*
+ * No need for locking here because there are no other users,
+ * by definition.
+ */
+
+ list_for_each_entry_safe(trans, tmp, &u->transactions, list) {
+ xenbus_transaction_end(trans->handle, 1);
+ list_del(&trans->list);
+ kfree(trans);
+ }
+
+ list_for_each_entry_safe(watch, tmp_watch, &u->watches, list) {
+ unregister_xenbus_watch(&watch->watch);
+ list_del(&watch->list);
+ free_watch_adapter(watch);
+ }
+
+ list_for_each_entry_safe(rb, tmp_rb, &u->read_buffers, list) {
+ list_del(&rb->list);
+ kfree(rb);
+ }
+ kfree(u);
+
+ return 0;
+}
+
+static unsigned int xenbus_file_poll(struct file *file, poll_table *wait)
+{
+ struct xenbus_file_priv *u = file->private_data;
+
+ poll_wait(file, &u->read_waitq, wait);
+ if (!list_empty(&u->read_buffers))
+ return POLLIN | POLLRDNORM;
+ return 0;
+}
+
+const struct file_operations xenbus_file_ops = {
+ .read = xenbus_file_read,
+ .write = xenbus_file_write,
+ .open = xenbus_file_open,
+ .release = xenbus_file_release,
+ .poll = xenbus_file_poll,
+ .llseek = no_llseek,
+};
diff --git a/drivers/xen/xenfs/xenfs.h b/drivers/xen/xenfs/xenfs.h
new file mode 100644
index 00000000..b68aa620
--- /dev/null
+++ b/drivers/xen/xenfs/xenfs.h
@@ -0,0 +1,9 @@
+#ifndef _XENFS_XENBUS_H
+#define _XENFS_XENBUS_H
+
+extern const struct file_operations xenbus_file_ops;
+extern const struct file_operations privcmd_file_ops;
+extern const struct file_operations xsd_kva_file_ops;
+extern const struct file_operations xsd_port_file_ops;
+
+#endif /* _XENFS_XENBUS_H */
diff --git a/drivers/xen/xenfs/xenstored.c b/drivers/xen/xenfs/xenstored.c
new file mode 100644
index 00000000..fef20dbc
--- /dev/null
+++ b/drivers/xen/xenfs/xenstored.c
@@ -0,0 +1,68 @@
+#include <linux/slab.h>
+#include <linux/types.h>
+#include <linux/mm.h>
+#include <linux/fs.h>
+
+#include <xen/page.h>
+
+#include "xenfs.h"
+#include "../xenbus/xenbus_comms.h"
+
+static ssize_t xsd_read(struct file *file, char __user *buf,
+ size_t size, loff_t *off)
+{
+ const char *str = (const char *)file->private_data;
+ return simple_read_from_buffer(buf, size, off, str, strlen(str));
+}
+
+static int xsd_release(struct inode *inode, struct file *file)
+{
+ kfree(file->private_data);
+ return 0;
+}
+
+static int xsd_kva_open(struct inode *inode, struct file *file)
+{
+ file->private_data = (void *)kasprintf(GFP_KERNEL, "0x%p",
+ xen_store_interface);
+ if (!file->private_data)
+ return -ENOMEM;
+ return 0;
+}
+
+static int xsd_kva_mmap(struct file *file, struct vm_area_struct *vma)
+{
+ size_t size = vma->vm_end - vma->vm_start;
+
+ if ((size > PAGE_SIZE) || (vma->vm_pgoff != 0))
+ return -EINVAL;
+
+ if (remap_pfn_range(vma, vma->vm_start,
+ virt_to_pfn(xen_store_interface),
+ size, vma->vm_page_prot))
+ return -EAGAIN;
+
+ return 0;
+}
+
+const struct file_operations xsd_kva_file_ops = {
+ .open = xsd_kva_open,
+ .mmap = xsd_kva_mmap,
+ .read = xsd_read,
+ .release = xsd_release,
+};
+
+static int xsd_port_open(struct inode *inode, struct file *file)
+{
+ file->private_data = (void *)kasprintf(GFP_KERNEL, "%d",
+ xen_store_evtchn);
+ if (!file->private_data)
+ return -ENOMEM;
+ return 0;
+}
+
+const struct file_operations xsd_port_file_ops = {
+ .open = xsd_port_open,
+ .read = xsd_read,
+ .release = xsd_release,
+};