From 041d1ea37802bf7178a31a53f96c26efa6b8fb7b Mon Sep 17 00:00:00 2001 From: James Date: Fri, 16 Nov 2012 10:41:01 +0000 Subject: fish --- grub-core/kern/disk.c | 604 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 604 insertions(+) create mode 100644 grub-core/kern/disk.c (limited to 'grub-core/kern/disk.c') diff --git a/grub-core/kern/disk.c b/grub-core/kern/disk.c new file mode 100644 index 0000000..807ee42 --- /dev/null +++ b/grub-core/kern/disk.c @@ -0,0 +1,604 @@ +/* + * GRUB -- GRand Unified Bootloader + * Copyright (C) 2002,2003,2004,2006,2007,2008,2009,2010 Free Software Foundation, Inc. + * + * GRUB 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 3 of the License, or + * (at your option) any later version. + * + * GRUB 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 GRUB. If not, see . + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +#define GRUB_CACHE_TIMEOUT 2 + +/* The last time the disk was used. */ +static grub_uint64_t grub_last_time = 0; + + +/* Disk cache. */ +struct grub_disk_cache +{ + enum grub_disk_dev_id dev_id; + unsigned long disk_id; + grub_disk_addr_t sector; + char *data; + int lock; +}; + +static struct grub_disk_cache grub_disk_cache_table[GRUB_DISK_CACHE_NUM]; + +void (*grub_disk_firmware_fini) (void); +int grub_disk_firmware_is_tainted; + +grub_err_t (* grub_disk_ata_pass_through) (grub_disk_t, + struct grub_disk_ata_pass_through_parms *); + + +#if 0 +static unsigned long grub_disk_cache_hits; +static unsigned long grub_disk_cache_misses; + +void +grub_disk_cache_get_performance (unsigned long *hits, unsigned long *misses) +{ + *hits = grub_disk_cache_hits; + *misses = grub_disk_cache_misses; +} +#endif + +static unsigned +grub_disk_cache_get_index (unsigned long dev_id, unsigned long disk_id, + grub_disk_addr_t sector) +{ + return ((dev_id * 524287UL + disk_id * 2606459UL + + ((unsigned) (sector >> GRUB_DISK_CACHE_BITS))) + % GRUB_DISK_CACHE_NUM); +} + +static void +grub_disk_cache_invalidate (unsigned long dev_id, unsigned long disk_id, + grub_disk_addr_t sector) +{ + unsigned index; + struct grub_disk_cache *cache; + + sector &= ~(GRUB_DISK_CACHE_SIZE - 1); + index = grub_disk_cache_get_index (dev_id, disk_id, sector); + cache = grub_disk_cache_table + index; + + if (cache->dev_id == dev_id && cache->disk_id == disk_id + && cache->sector == sector && cache->data) + { + cache->lock = 1; + grub_free (cache->data); + cache->data = 0; + cache->lock = 0; + } +} + +void +grub_disk_cache_invalidate_all (void) +{ + unsigned i; + + for (i = 0; i < GRUB_DISK_CACHE_NUM; i++) + { + struct grub_disk_cache *cache = grub_disk_cache_table + i; + + if (cache->data && ! cache->lock) + { + grub_free (cache->data); + cache->data = 0; + } + } +} + +static char * +grub_disk_cache_fetch (unsigned long dev_id, unsigned long disk_id, + grub_disk_addr_t sector) +{ + struct grub_disk_cache *cache; + unsigned index; + + index = grub_disk_cache_get_index (dev_id, disk_id, sector); + cache = grub_disk_cache_table + index; + + if (cache->dev_id == dev_id && cache->disk_id == disk_id + && cache->sector == sector) + { + cache->lock = 1; +#if 0 + grub_disk_cache_hits++; +#endif + return cache->data; + } + +#if 0 + grub_disk_cache_misses++; +#endif + + return 0; +} + +static void +grub_disk_cache_unlock (unsigned long dev_id, unsigned long disk_id, + grub_disk_addr_t sector) +{ + struct grub_disk_cache *cache; + unsigned index; + + index = grub_disk_cache_get_index (dev_id, disk_id, sector); + cache = grub_disk_cache_table + index; + + if (cache->dev_id == dev_id && cache->disk_id == disk_id + && cache->sector == sector) + cache->lock = 0; +} + +static grub_err_t +grub_disk_cache_store (unsigned long dev_id, unsigned long disk_id, + grub_disk_addr_t sector, const char *data) +{ + unsigned index; + struct grub_disk_cache *cache; + + index = grub_disk_cache_get_index (dev_id, disk_id, sector); + cache = grub_disk_cache_table + index; + + cache->lock = 1; + grub_free (cache->data); + cache->data = 0; + cache->lock = 0; + + cache->data = grub_malloc (GRUB_DISK_SECTOR_SIZE << GRUB_DISK_CACHE_BITS); + if (! cache->data) + return grub_errno; + + grub_memcpy (cache->data, data, + GRUB_DISK_SECTOR_SIZE << GRUB_DISK_CACHE_BITS); + cache->dev_id = dev_id; + cache->disk_id = disk_id; + cache->sector = sector; + + return GRUB_ERR_NONE; +} + + + +static grub_disk_dev_t grub_disk_dev_list; + +void +grub_disk_dev_register (grub_disk_dev_t dev) +{ + dev->next = grub_disk_dev_list; + grub_disk_dev_list = dev; +} + +void +grub_disk_dev_unregister (grub_disk_dev_t dev) +{ + grub_disk_dev_t *p, q; + + for (p = &grub_disk_dev_list, q = *p; q; p = &(q->next), q = q->next) + if (q == dev) + { + *p = q->next; + break; + } +} + +int +grub_disk_dev_iterate (int (*hook) (const char *name)) +{ + grub_disk_dev_t p; + + for (p = grub_disk_dev_list; p; p = p->next) + if (p->iterate && (p->iterate) (hook)) + return 1; + + return 0; +} + +/* Return the location of the first ',', if any, which is not + escaped by a '\'. */ +static const char * +find_part_sep (const char *name) +{ + const char *p = name; + char c; + + while ((c = *p++) != '\0') + { + if (c == '\\' && *p == ',') + p++; + else if (c == ',') + return p - 1; + } + return NULL; +} + +grub_disk_t +grub_disk_open (const char *name) +{ + const char *p; + grub_disk_t disk; + grub_disk_dev_t dev; + char *raw = (char *) name; + grub_uint64_t current_time; + + grub_dprintf ("disk", "Opening `%s'...\n", name); + + disk = (grub_disk_t) grub_zalloc (sizeof (*disk)); + if (! disk) + return 0; + + p = find_part_sep (name); + if (p) + { + grub_size_t len = p - name; + + raw = grub_malloc (len + 1); + if (! raw) + goto fail; + + grub_memcpy (raw, name, len); + raw[len] = '\0'; + disk->name = grub_strdup (raw); + } + else + disk->name = grub_strdup (name); + if (! disk->name) + goto fail; + + + for (dev = grub_disk_dev_list; dev; dev = dev->next) + { + if ((dev->open) (raw, disk) == GRUB_ERR_NONE) + break; + else if (grub_errno == GRUB_ERR_UNKNOWN_DEVICE) + grub_errno = GRUB_ERR_NONE; + else + goto fail; + } + + if (! dev) + { + grub_error (GRUB_ERR_UNKNOWN_DEVICE, "no such disk"); + goto fail; + } + + disk->dev = dev; + + if (p) + { + disk->partition = grub_partition_probe (disk, p + 1); + if (! disk->partition) + { + grub_error (GRUB_ERR_UNKNOWN_DEVICE, "no such partition"); + goto fail; + } + } + + /* The cache will be invalidated about 2 seconds after a device was + closed. */ + current_time = grub_get_time_ms (); + + if (current_time > (grub_last_time + + GRUB_CACHE_TIMEOUT * 1000)) + grub_disk_cache_invalidate_all (); + + grub_last_time = current_time; + + fail: + + if (raw && raw != name) + grub_free (raw); + + if (grub_errno != GRUB_ERR_NONE) + { + grub_error_push (); + grub_dprintf ("disk", "Opening `%s' failed.\n", name); + grub_error_pop (); + + grub_disk_close (disk); + return 0; + } + + return disk; +} + +void +grub_disk_close (grub_disk_t disk) +{ + grub_partition_t part; + grub_dprintf ("disk", "Closing `%s'.\n", disk->name); + + if (disk->dev && disk->dev->close) + (disk->dev->close) (disk); + + /* Reset the timer. */ + grub_last_time = grub_get_time_ms (); + + while (disk->partition) + { + part = disk->partition->parent; + grub_free (disk->partition); + disk->partition = part; + } + grub_free ((void *) disk->name); + grub_free (disk); +} + +/* This function performs three tasks: + - Make sectors disk relative from partition relative. + - Normalize offset to be less than the sector size. + - Verify that the range is inside the partition. */ +static grub_err_t +grub_disk_adjust_range (grub_disk_t disk, grub_disk_addr_t *sector, + grub_off_t *offset, grub_size_t size) +{ + grub_partition_t part; + *sector += *offset >> GRUB_DISK_SECTOR_BITS; + *offset &= GRUB_DISK_SECTOR_SIZE - 1; + + for (part = disk->partition; part; part = part->parent) + { + grub_disk_addr_t start; + grub_uint64_t len; + + start = part->start; + len = part->len; + + if (*sector >= len + || len - *sector < ((*offset + size + GRUB_DISK_SECTOR_SIZE - 1) + >> GRUB_DISK_SECTOR_BITS)) + return grub_error (GRUB_ERR_OUT_OF_RANGE, "out of partition"); + + *sector += start; + } + + if (disk->total_sectors <= *sector + || ((*offset + size + GRUB_DISK_SECTOR_SIZE - 1) + >> GRUB_DISK_SECTOR_BITS) > disk->total_sectors - *sector) + return grub_error (GRUB_ERR_OUT_OF_RANGE, "out of disk"); + + return GRUB_ERR_NONE; +} + +/* Read data from the disk. */ +grub_err_t +grub_disk_read (grub_disk_t disk, grub_disk_addr_t sector, + grub_off_t offset, grub_size_t size, void *buf) +{ + char *tmp_buf; + unsigned real_offset; + + /* First of all, check if the region is within the disk. */ + if (grub_disk_adjust_range (disk, §or, &offset, size) != GRUB_ERR_NONE) + { + grub_error_push (); + grub_dprintf ("disk", "Read out of range: sector 0x%llx (%s).\n", + (unsigned long long) sector, grub_errmsg); + grub_error_pop (); + return grub_errno; + } + + real_offset = offset; + + /* Allocate a temporary buffer. */ + tmp_buf = grub_malloc (GRUB_DISK_SECTOR_SIZE << GRUB_DISK_CACHE_BITS); + if (! tmp_buf) + return grub_errno; + + /* Until SIZE is zero... */ + while (size) + { + char *data; + grub_disk_addr_t start_sector; + grub_size_t len; + grub_size_t pos; + + /* For reading bulk data. */ + start_sector = sector & ~(GRUB_DISK_CACHE_SIZE - 1); + pos = (sector - start_sector) << GRUB_DISK_SECTOR_BITS; + len = ((GRUB_DISK_SECTOR_SIZE << GRUB_DISK_CACHE_BITS) + - pos - real_offset); + if (len > size) + len = size; + + /* Fetch the cache. */ + data = grub_disk_cache_fetch (disk->dev->id, disk->id, start_sector); + if (data) + { + /* Just copy it! */ + grub_memcpy (buf, data + pos + real_offset, len); + grub_disk_cache_unlock (disk->dev->id, disk->id, start_sector); + } + else + { + /* Otherwise read data from the disk actually. */ + if (start_sector + GRUB_DISK_CACHE_SIZE > disk->total_sectors + || (disk->dev->read) (disk, start_sector, + GRUB_DISK_CACHE_SIZE, tmp_buf) + != GRUB_ERR_NONE) + { + /* Uggh... Failed. Instead, just read necessary data. */ + unsigned num; + char *p; + + grub_errno = GRUB_ERR_NONE; + + num = ((size + real_offset + GRUB_DISK_SECTOR_SIZE - 1) + >> GRUB_DISK_SECTOR_BITS); + + p = grub_realloc (tmp_buf, num << GRUB_DISK_SECTOR_BITS); + if (!p) + goto finish; + + tmp_buf = p; + + if ((disk->dev->read) (disk, sector, num, tmp_buf)) + { + grub_error_push (); + grub_dprintf ("disk", "%s read failed\n", disk->name); + grub_error_pop (); + goto finish; + } + + grub_memcpy (buf, tmp_buf + real_offset, size); + + /* Call the read hook, if any. */ + if (disk->read_hook) + while (size) + { + grub_size_t to_read = (size > GRUB_DISK_SECTOR_SIZE) ? GRUB_DISK_SECTOR_SIZE : size; + (disk->read_hook) (sector, real_offset, + to_read); + if (grub_errno != GRUB_ERR_NONE) + goto finish; + + sector++; + size -= to_read - real_offset; + real_offset = 0; + } + + /* This must be the end. */ + goto finish; + } + + /* Copy it and store it in the disk cache. */ + grub_memcpy (buf, tmp_buf + pos + real_offset, len); + grub_disk_cache_store (disk->dev->id, disk->id, + start_sector, tmp_buf); + } + + /* Call the read hook, if any. */ + if (disk->read_hook) + { + grub_disk_addr_t s = sector; + grub_size_t l = len; + + while (l) + { + (disk->read_hook) (s, real_offset, + ((l > GRUB_DISK_SECTOR_SIZE) + ? GRUB_DISK_SECTOR_SIZE + : l)); + + if (l < GRUB_DISK_SECTOR_SIZE - real_offset) + break; + + s++; + l -= GRUB_DISK_SECTOR_SIZE - real_offset; + real_offset = 0; + } + } + + sector = start_sector + GRUB_DISK_CACHE_SIZE; + buf = (char *) buf + len; + size -= len; + real_offset = 0; + } + + finish: + + grub_free (tmp_buf); + + return grub_errno; +} + +grub_err_t +grub_disk_write (grub_disk_t disk, grub_disk_addr_t sector, + grub_off_t offset, grub_size_t size, const void *buf) +{ + unsigned real_offset; + + grub_dprintf ("disk", "Writing `%s'...\n", disk->name); + + if (grub_disk_adjust_range (disk, §or, &offset, size) != GRUB_ERR_NONE) + return -1; + + real_offset = offset; + + while (size) + { + if (real_offset != 0 || (size < GRUB_DISK_SECTOR_SIZE && size != 0)) + { + char tmp_buf[GRUB_DISK_SECTOR_SIZE]; + grub_size_t len; + grub_partition_t part; + + part = disk->partition; + disk->partition = 0; + if (grub_disk_read (disk, sector, 0, GRUB_DISK_SECTOR_SIZE, tmp_buf) + != GRUB_ERR_NONE) + { + disk->partition = part; + goto finish; + } + disk->partition = part; + + len = GRUB_DISK_SECTOR_SIZE - real_offset; + if (len > size) + len = size; + + grub_memcpy (tmp_buf + real_offset, buf, len); + + grub_disk_cache_invalidate (disk->dev->id, disk->id, sector); + + if ((disk->dev->write) (disk, sector, 1, tmp_buf) != GRUB_ERR_NONE) + goto finish; + + sector++; + buf = (char *) buf + len; + size -= len; + real_offset = 0; + } + else + { + grub_size_t len; + grub_size_t n; + + len = size & ~(GRUB_DISK_SECTOR_SIZE - 1); + n = size >> GRUB_DISK_SECTOR_BITS; + + if ((disk->dev->write) (disk, sector, n, buf) != GRUB_ERR_NONE) + goto finish; + + while (n--) + grub_disk_cache_invalidate (disk->dev->id, disk->id, sector++); + + buf = (char *) buf + len; + size -= len; + } + } + + finish: + + return grub_errno; +} + +grub_uint64_t +grub_disk_get_size (grub_disk_t disk) +{ + if (disk->partition) + return grub_partition_get_len (disk->partition); + else + return disk->total_sectors; +} -- cgit v1.2.3