grub/grub-core/disk/memdisk.c
Vladimir Serbinenko cc6fb517de Remove practice of assigning random const pointers to device id.
This is not required as cache code already checks driver id as well.
2013-12-16 14:49:11 +01:00

116 lines
3.2 KiB
C

/* memdisk.c - Access embedded memory disk. */
/*
* GRUB -- GRand Unified Bootloader
* Copyright (C) 2007,2008 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/dl.h>
#include <grub/kernel.h>
#include <grub/misc.h>
#include <grub/mm.h>
#include <grub/types.h>
GRUB_MOD_LICENSE ("GPLv3+");
static char *memdisk_addr;
static grub_off_t memdisk_size = 0;
static int
grub_memdisk_iterate (grub_disk_dev_iterate_hook_t hook, void *hook_data,
grub_disk_pull_t pull)
{
if (pull != GRUB_DISK_PULL_NONE)
return 0;
return hook ("memdisk", hook_data);
}
static grub_err_t
grub_memdisk_open (const char *name, grub_disk_t disk)
{
if (grub_strcmp (name, "memdisk"))
return grub_error (GRUB_ERR_UNKNOWN_DEVICE, "not a memdisk");
disk->total_sectors = memdisk_size / GRUB_DISK_SECTOR_SIZE;
disk->max_agglomerate = GRUB_DISK_MAX_MAX_AGGLOMERATE;
disk->id = 0;
return GRUB_ERR_NONE;
}
static void
grub_memdisk_close (grub_disk_t disk __attribute((unused)))
{
}
static grub_err_t
grub_memdisk_read (grub_disk_t disk __attribute((unused)), grub_disk_addr_t sector,
grub_size_t size, char *buf)
{
grub_memcpy (buf, memdisk_addr + (sector << GRUB_DISK_SECTOR_BITS), size << GRUB_DISK_SECTOR_BITS);
return 0;
}
static grub_err_t
grub_memdisk_write (grub_disk_t disk __attribute((unused)), grub_disk_addr_t sector,
grub_size_t size, const char *buf)
{
grub_memcpy (memdisk_addr + (sector << GRUB_DISK_SECTOR_BITS), buf, size << GRUB_DISK_SECTOR_BITS);
return 0;
}
static struct grub_disk_dev grub_memdisk_dev =
{
.name = "memdisk",
.id = GRUB_DISK_DEVICE_MEMDISK_ID,
.iterate = grub_memdisk_iterate,
.open = grub_memdisk_open,
.close = grub_memdisk_close,
.read = grub_memdisk_read,
.write = grub_memdisk_write,
.next = 0
};
GRUB_MOD_INIT(memdisk)
{
struct grub_module_header *header;
FOR_MODULES (header)
if (header->type == OBJ_TYPE_MEMDISK)
{
char *memdisk_orig_addr;
memdisk_orig_addr = (char *) header + sizeof (struct grub_module_header);
grub_dprintf ("memdisk", "Found memdisk image at %p\n", memdisk_orig_addr);
memdisk_size = header->size - sizeof (struct grub_module_header);
memdisk_addr = grub_malloc (memdisk_size);
grub_dprintf ("memdisk", "Copying memdisk image to dynamic memory\n");
grub_memmove (memdisk_addr, memdisk_orig_addr, memdisk_size);
grub_disk_dev_register (&grub_memdisk_dev);
break;
}
}
GRUB_MOD_FINI(memdisk)
{
if (! memdisk_size)
return;
grub_free (memdisk_addr);
grub_disk_dev_unregister (&grub_memdisk_dev);
}