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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 /arch/powerpc/kernel/nvram_64.c
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initial_commit
Diffstat (limited to 'arch/powerpc/kernel/nvram_64.c')
-rw-r--r--arch/powerpc/kernel/nvram_64.c564
1 files changed, 564 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/nvram_64.c b/arch/powerpc/kernel/nvram_64.c
new file mode 100644
index 00000000..bec1e930
--- /dev/null
+++ b/arch/powerpc/kernel/nvram_64.c
@@ -0,0 +1,564 @@
+/*
+ * c 2001 PPC 64 Team, IBM Corp
+ *
+ * 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.
+ *
+ * /dev/nvram driver for PPC64
+ *
+ * This perhaps should live in drivers/char
+ *
+ * TODO: Split the /dev/nvram part (that one can use
+ * drivers/char/generic_nvram.c) from the arch & partition
+ * parsing code.
+ */
+
+#include <linux/module.h>
+
+#include <linux/types.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/miscdevice.h>
+#include <linux/fcntl.h>
+#include <linux/nvram.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <asm/uaccess.h>
+#include <asm/nvram.h>
+#include <asm/rtas.h>
+#include <asm/prom.h>
+#include <asm/machdep.h>
+
+#undef DEBUG_NVRAM
+
+#define NVRAM_HEADER_LEN sizeof(struct nvram_header)
+#define NVRAM_BLOCK_LEN NVRAM_HEADER_LEN
+
+/* If change this size, then change the size of NVNAME_LEN */
+struct nvram_header {
+ unsigned char signature;
+ unsigned char checksum;
+ unsigned short length;
+ /* Terminating null required only for names < 12 chars. */
+ char name[12];
+};
+
+struct nvram_partition {
+ struct list_head partition;
+ struct nvram_header header;
+ unsigned int index;
+};
+
+static LIST_HEAD(nvram_partitions);
+
+static loff_t dev_nvram_llseek(struct file *file, loff_t offset, int origin)
+{
+ int size;
+
+ if (ppc_md.nvram_size == NULL)
+ return -ENODEV;
+ size = ppc_md.nvram_size();
+
+ switch (origin) {
+ case 1:
+ offset += file->f_pos;
+ break;
+ case 2:
+ offset += size;
+ break;
+ }
+ if (offset < 0)
+ return -EINVAL;
+ file->f_pos = offset;
+ return file->f_pos;
+}
+
+
+static ssize_t dev_nvram_read(struct file *file, char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ ssize_t ret;
+ char *tmp = NULL;
+ ssize_t size;
+
+ ret = -ENODEV;
+ if (!ppc_md.nvram_size)
+ goto out;
+
+ ret = 0;
+ size = ppc_md.nvram_size();
+ if (*ppos >= size || size < 0)
+ goto out;
+
+ count = min_t(size_t, count, size - *ppos);
+ count = min(count, PAGE_SIZE);
+
+ ret = -ENOMEM;
+ tmp = kmalloc(count, GFP_KERNEL);
+ if (!tmp)
+ goto out;
+
+ ret = ppc_md.nvram_read(tmp, count, ppos);
+ if (ret <= 0)
+ goto out;
+
+ if (copy_to_user(buf, tmp, ret))
+ ret = -EFAULT;
+
+out:
+ kfree(tmp);
+ return ret;
+
+}
+
+static ssize_t dev_nvram_write(struct file *file, const char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ ssize_t ret;
+ char *tmp = NULL;
+ ssize_t size;
+
+ ret = -ENODEV;
+ if (!ppc_md.nvram_size)
+ goto out;
+
+ ret = 0;
+ size = ppc_md.nvram_size();
+ if (*ppos >= size || size < 0)
+ goto out;
+
+ count = min_t(size_t, count, size - *ppos);
+ count = min(count, PAGE_SIZE);
+
+ ret = -ENOMEM;
+ tmp = kmalloc(count, GFP_KERNEL);
+ if (!tmp)
+ goto out;
+
+ ret = -EFAULT;
+ if (copy_from_user(tmp, buf, count))
+ goto out;
+
+ ret = ppc_md.nvram_write(tmp, count, ppos);
+
+out:
+ kfree(tmp);
+ return ret;
+
+}
+
+static long dev_nvram_ioctl(struct file *file, unsigned int cmd,
+ unsigned long arg)
+{
+ switch(cmd) {
+#ifdef CONFIG_PPC_PMAC
+ case OBSOLETE_PMAC_NVRAM_GET_OFFSET:
+ printk(KERN_WARNING "nvram: Using obsolete PMAC_NVRAM_GET_OFFSET ioctl\n");
+ case IOC_NVRAM_GET_OFFSET: {
+ int part, offset;
+
+ if (!machine_is(powermac))
+ return -EINVAL;
+ if (copy_from_user(&part, (void __user*)arg, sizeof(part)) != 0)
+ return -EFAULT;
+ if (part < pmac_nvram_OF || part > pmac_nvram_NR)
+ return -EINVAL;
+ offset = pmac_get_partition(part);
+ if (offset < 0)
+ return offset;
+ if (copy_to_user((void __user*)arg, &offset, sizeof(offset)) != 0)
+ return -EFAULT;
+ return 0;
+ }
+#endif /* CONFIG_PPC_PMAC */
+ default:
+ return -EINVAL;
+ }
+}
+
+const struct file_operations nvram_fops = {
+ .owner = THIS_MODULE,
+ .llseek = dev_nvram_llseek,
+ .read = dev_nvram_read,
+ .write = dev_nvram_write,
+ .unlocked_ioctl = dev_nvram_ioctl,
+};
+
+static struct miscdevice nvram_dev = {
+ NVRAM_MINOR,
+ "nvram",
+ &nvram_fops
+};
+
+
+#ifdef DEBUG_NVRAM
+static void __init nvram_print_partitions(char * label)
+{
+ struct nvram_partition * tmp_part;
+
+ printk(KERN_WARNING "--------%s---------\n", label);
+ printk(KERN_WARNING "indx\t\tsig\tchks\tlen\tname\n");
+ list_for_each_entry(tmp_part, &nvram_partitions, partition) {
+ printk(KERN_WARNING "%4d \t%02x\t%02x\t%d\t%12s\n",
+ tmp_part->index, tmp_part->header.signature,
+ tmp_part->header.checksum, tmp_part->header.length,
+ tmp_part->header.name);
+ }
+}
+#endif
+
+
+static int __init nvram_write_header(struct nvram_partition * part)
+{
+ loff_t tmp_index;
+ int rc;
+
+ tmp_index = part->index;
+ rc = ppc_md.nvram_write((char *)&part->header, NVRAM_HEADER_LEN, &tmp_index);
+
+ return rc;
+}
+
+
+static unsigned char __init nvram_checksum(struct nvram_header *p)
+{
+ unsigned int c_sum, c_sum2;
+ unsigned short *sp = (unsigned short *)p->name; /* assume 6 shorts */
+ c_sum = p->signature + p->length + sp[0] + sp[1] + sp[2] + sp[3] + sp[4] + sp[5];
+
+ /* The sum may have spilled into the 3rd byte. Fold it back. */
+ c_sum = ((c_sum & 0xffff) + (c_sum >> 16)) & 0xffff;
+ /* The sum cannot exceed 2 bytes. Fold it into a checksum */
+ c_sum2 = (c_sum >> 8) + (c_sum << 8);
+ c_sum = ((c_sum + c_sum2) >> 8) & 0xff;
+ return c_sum;
+}
+
+/*
+ * Per the criteria passed via nvram_remove_partition(), should this
+ * partition be removed? 1=remove, 0=keep
+ */
+static int nvram_can_remove_partition(struct nvram_partition *part,
+ const char *name, int sig, const char *exceptions[])
+{
+ if (part->header.signature != sig)
+ return 0;
+ if (name) {
+ if (strncmp(name, part->header.name, 12))
+ return 0;
+ } else if (exceptions) {
+ const char **except;
+ for (except = exceptions; *except; except++) {
+ if (!strncmp(*except, part->header.name, 12))
+ return 0;
+ }
+ }
+ return 1;
+}
+
+/**
+ * nvram_remove_partition - Remove one or more partitions in nvram
+ * @name: name of the partition to remove, or NULL for a
+ * signature only match
+ * @sig: signature of the partition(s) to remove
+ * @exceptions: When removing all partitions with a matching signature,
+ * leave these alone.
+ */
+
+int __init nvram_remove_partition(const char *name, int sig,
+ const char *exceptions[])
+{
+ struct nvram_partition *part, *prev, *tmp;
+ int rc;
+
+ list_for_each_entry(part, &nvram_partitions, partition) {
+ if (!nvram_can_remove_partition(part, name, sig, exceptions))
+ continue;
+
+ /* Make partition a free partition */
+ part->header.signature = NVRAM_SIG_FREE;
+ strncpy(part->header.name, "wwwwwwwwwwww", 12);
+ part->header.checksum = nvram_checksum(&part->header);
+ rc = nvram_write_header(part);
+ if (rc <= 0) {
+ printk(KERN_ERR "nvram_remove_partition: nvram_write failed (%d)\n", rc);
+ return rc;
+ }
+ }
+
+ /* Merge contiguous ones */
+ prev = NULL;
+ list_for_each_entry_safe(part, tmp, &nvram_partitions, partition) {
+ if (part->header.signature != NVRAM_SIG_FREE) {
+ prev = NULL;
+ continue;
+ }
+ if (prev) {
+ prev->header.length += part->header.length;
+ prev->header.checksum = nvram_checksum(&part->header);
+ rc = nvram_write_header(part);
+ if (rc <= 0) {
+ printk(KERN_ERR "nvram_remove_partition: nvram_write failed (%d)\n", rc);
+ return rc;
+ }
+ list_del(&part->partition);
+ kfree(part);
+ } else
+ prev = part;
+ }
+
+ return 0;
+}
+
+/**
+ * nvram_create_partition - Create a partition in nvram
+ * @name: name of the partition to create
+ * @sig: signature of the partition to create
+ * @req_size: size of data to allocate in bytes
+ * @min_size: minimum acceptable size (0 means req_size)
+ *
+ * Returns a negative error code or a positive nvram index
+ * of the beginning of the data area of the newly created
+ * partition. If you provided a min_size smaller than req_size
+ * you need to query for the actual size yourself after the
+ * call using nvram_partition_get_size().
+ */
+loff_t __init nvram_create_partition(const char *name, int sig,
+ int req_size, int min_size)
+{
+ struct nvram_partition *part;
+ struct nvram_partition *new_part;
+ struct nvram_partition *free_part = NULL;
+ static char nv_init_vals[16];
+ loff_t tmp_index;
+ long size = 0;
+ int rc;
+
+ /* Convert sizes from bytes to blocks */
+ req_size = _ALIGN_UP(req_size, NVRAM_BLOCK_LEN) / NVRAM_BLOCK_LEN;
+ min_size = _ALIGN_UP(min_size, NVRAM_BLOCK_LEN) / NVRAM_BLOCK_LEN;
+
+ /* If no minimum size specified, make it the same as the
+ * requested size
+ */
+ if (min_size == 0)
+ min_size = req_size;
+ if (min_size > req_size)
+ return -EINVAL;
+
+ /* Now add one block to each for the header */
+ req_size += 1;
+ min_size += 1;
+
+ /* Find a free partition that will give us the maximum needed size
+ If can't find one that will give us the minimum size needed */
+ list_for_each_entry(part, &nvram_partitions, partition) {
+ if (part->header.signature != NVRAM_SIG_FREE)
+ continue;
+
+ if (part->header.length >= req_size) {
+ size = req_size;
+ free_part = part;
+ break;
+ }
+ if (part->header.length > size &&
+ part->header.length >= min_size) {
+ size = part->header.length;
+ free_part = part;
+ }
+ }
+ if (!size)
+ return -ENOSPC;
+
+ /* Create our OS partition */
+ new_part = kmalloc(sizeof(*new_part), GFP_KERNEL);
+ if (!new_part) {
+ pr_err("nvram_create_os_partition: kmalloc failed\n");
+ return -ENOMEM;
+ }
+
+ new_part->index = free_part->index;
+ new_part->header.signature = sig;
+ new_part->header.length = size;
+ strncpy(new_part->header.name, name, 12);
+ new_part->header.checksum = nvram_checksum(&new_part->header);
+
+ rc = nvram_write_header(new_part);
+ if (rc <= 0) {
+ pr_err("nvram_create_os_partition: nvram_write_header "
+ "failed (%d)\n", rc);
+ return rc;
+ }
+ list_add_tail(&new_part->partition, &free_part->partition);
+
+ /* Adjust or remove the partition we stole the space from */
+ if (free_part->header.length > size) {
+ free_part->index += size * NVRAM_BLOCK_LEN;
+ free_part->header.length -= size;
+ free_part->header.checksum = nvram_checksum(&free_part->header);
+ rc = nvram_write_header(free_part);
+ if (rc <= 0) {
+ pr_err("nvram_create_os_partition: nvram_write_header "
+ "failed (%d)\n", rc);
+ return rc;
+ }
+ } else {
+ list_del(&free_part->partition);
+ kfree(free_part);
+ }
+
+ /* Clear the new partition */
+ for (tmp_index = new_part->index + NVRAM_HEADER_LEN;
+ tmp_index < ((size - 1) * NVRAM_BLOCK_LEN);
+ tmp_index += NVRAM_BLOCK_LEN) {
+ rc = ppc_md.nvram_write(nv_init_vals, NVRAM_BLOCK_LEN, &tmp_index);
+ if (rc <= 0) {
+ pr_err("nvram_create_partition: nvram_write failed (%d)\n", rc);
+ return rc;
+ }
+ }
+
+ return new_part->index + NVRAM_HEADER_LEN;
+}
+
+/**
+ * nvram_get_partition_size - Get the data size of an nvram partition
+ * @data_index: This is the offset of the start of the data of
+ * the partition. The same value that is returned by
+ * nvram_create_partition().
+ */
+int nvram_get_partition_size(loff_t data_index)
+{
+ struct nvram_partition *part;
+
+ list_for_each_entry(part, &nvram_partitions, partition) {
+ if (part->index + NVRAM_HEADER_LEN == data_index)
+ return (part->header.length - 1) * NVRAM_BLOCK_LEN;
+ }
+ return -1;
+}
+
+
+/**
+ * nvram_find_partition - Find an nvram partition by signature and name
+ * @name: Name of the partition or NULL for any name
+ * @sig: Signature to test against
+ * @out_size: if non-NULL, returns the size of the data part of the partition
+ */
+loff_t nvram_find_partition(const char *name, int sig, int *out_size)
+{
+ struct nvram_partition *p;
+
+ list_for_each_entry(p, &nvram_partitions, partition) {
+ if (p->header.signature == sig &&
+ (!name || !strncmp(p->header.name, name, 12))) {
+ if (out_size)
+ *out_size = (p->header.length - 1) *
+ NVRAM_BLOCK_LEN;
+ return p->index + NVRAM_HEADER_LEN;
+ }
+ }
+ return 0;
+}
+
+int __init nvram_scan_partitions(void)
+{
+ loff_t cur_index = 0;
+ struct nvram_header phead;
+ struct nvram_partition * tmp_part;
+ unsigned char c_sum;
+ char * header;
+ int total_size;
+ int err;
+
+ if (ppc_md.nvram_size == NULL || ppc_md.nvram_size() <= 0)
+ return -ENODEV;
+ total_size = ppc_md.nvram_size();
+
+ header = kmalloc(NVRAM_HEADER_LEN, GFP_KERNEL);
+ if (!header) {
+ printk(KERN_ERR "nvram_scan_partitions: Failed kmalloc\n");
+ return -ENOMEM;
+ }
+
+ while (cur_index < total_size) {
+
+ err = ppc_md.nvram_read(header, NVRAM_HEADER_LEN, &cur_index);
+ if (err != NVRAM_HEADER_LEN) {
+ printk(KERN_ERR "nvram_scan_partitions: Error parsing "
+ "nvram partitions\n");
+ goto out;
+ }
+
+ cur_index -= NVRAM_HEADER_LEN; /* nvram_read will advance us */
+
+ memcpy(&phead, header, NVRAM_HEADER_LEN);
+
+ err = 0;
+ c_sum = nvram_checksum(&phead);
+ if (c_sum != phead.checksum) {
+ printk(KERN_WARNING "WARNING: nvram partition checksum"
+ " was %02x, should be %02x!\n",
+ phead.checksum, c_sum);
+ printk(KERN_WARNING "Terminating nvram partition scan\n");
+ goto out;
+ }
+ if (!phead.length) {
+ printk(KERN_WARNING "WARNING: nvram corruption "
+ "detected: 0-length partition\n");
+ goto out;
+ }
+ tmp_part = (struct nvram_partition *)
+ kmalloc(sizeof(struct nvram_partition), GFP_KERNEL);
+ err = -ENOMEM;
+ if (!tmp_part) {
+ printk(KERN_ERR "nvram_scan_partitions: kmalloc failed\n");
+ goto out;
+ }
+
+ memcpy(&tmp_part->header, &phead, NVRAM_HEADER_LEN);
+ tmp_part->index = cur_index;
+ list_add_tail(&tmp_part->partition, &nvram_partitions);
+
+ cur_index += phead.length * NVRAM_BLOCK_LEN;
+ }
+ err = 0;
+
+#ifdef DEBUG_NVRAM
+ nvram_print_partitions("NVRAM Partitions");
+#endif
+
+ out:
+ kfree(header);
+ return err;
+}
+
+static int __init nvram_init(void)
+{
+ int rc;
+
+ BUILD_BUG_ON(NVRAM_BLOCK_LEN != 16);
+
+ if (ppc_md.nvram_size == NULL || ppc_md.nvram_size() <= 0)
+ return -ENODEV;
+
+ rc = misc_register(&nvram_dev);
+ if (rc != 0) {
+ printk(KERN_ERR "nvram_init: failed to register device\n");
+ return rc;
+ }
+
+ return rc;
+}
+
+void __exit nvram_cleanup(void)
+{
+ misc_deregister( &nvram_dev );
+}
+
+module_init(nvram_init);
+module_exit(nvram_cleanup);
+MODULE_LICENSE("GPL");