grub/grub-core/lib/disk.c
2013-10-27 15:44:55 +01:00

154 lines
3.8 KiB
C

/*
* 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 <http://www.gnu.org/licenses/>.
*/
#include <grub/disk.h>
#include <grub/err.h>
#include <grub/mm.h>
#include <grub/types.h>
#include <grub/partition.h>
#include <grub/misc.h>
#include <grub/time.h>
#include <grub/file.h>
#include <grub/i18n.h>
GRUB_MOD_LICENSE ("GPLv3+");
#include "../kern/disk_common.c"
static void
grub_disk_cache_invalidate (unsigned long dev_id, unsigned long disk_id,
grub_disk_addr_t sector)
{
unsigned cache_index;
struct grub_disk_cache *cache;
sector &= ~(GRUB_DISK_CACHE_SIZE - 1);
cache_index = grub_disk_cache_get_index (dev_id, disk_id, sector);
cache = grub_disk_cache_table + cache_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;
}
}
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_disk_addr_t aligned_sector;
grub_dprintf ("disk", "Writing `%s'...\n", disk->name);
if (grub_disk_adjust_range (disk, &sector, &offset, size) != GRUB_ERR_NONE)
return -1;
aligned_sector = (sector & ~((1 << (disk->log_sector_size
- GRUB_DISK_SECTOR_BITS)) - 1));
real_offset = offset + ((sector - aligned_sector) << GRUB_DISK_SECTOR_BITS);
sector = aligned_sector;
while (size)
{
if (real_offset != 0 || (size < (1U << disk->log_sector_size)
&& size != 0))
{
char *tmp_buf;
grub_size_t len;
grub_partition_t part;
tmp_buf = grub_malloc (1 << disk->log_sector_size);
if (!tmp_buf)
return grub_errno;
part = disk->partition;
disk->partition = 0;
if (grub_disk_read (disk, sector,
0, (1 << disk->log_sector_size), tmp_buf)
!= GRUB_ERR_NONE)
{
disk->partition = part;
grub_free (tmp_buf);
goto finish;
}
disk->partition = part;
len = (1 << disk->log_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, transform_sector (disk, sector),
1, tmp_buf) != GRUB_ERR_NONE)
{
grub_free (tmp_buf);
goto finish;
}
grub_free (tmp_buf);
sector += (1 << (disk->log_sector_size - GRUB_DISK_SECTOR_BITS));
buf = (const char *) buf + len;
size -= len;
real_offset = 0;
}
else
{
grub_size_t len;
grub_size_t n;
len = size & ~((1 << disk->log_sector_size) - 1);
n = size >> disk->log_sector_size;
if ((disk->dev->write) (disk, transform_sector (disk, sector),
n, buf) != GRUB_ERR_NONE)
goto finish;
while (n--)
{
grub_disk_cache_invalidate (disk->dev->id, disk->id, sector);
sector += (1 << (disk->log_sector_size - GRUB_DISK_SECTOR_BITS));
}
buf = (const char *) buf + len;
size -= len;
}
}
finish:
return grub_errno;
}
GRUB_MOD_INIT(disk)
{
grub_disk_write_weak = grub_disk_write;
}
GRUB_MOD_FINI(disk)
{
grub_disk_write_weak = NULL;
}