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/* Mmap management. */
/*
* GRUB -- GRand Unified Bootloader
* Copyright (C) 2009 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/machine/memory.h>
#include <grub/memory.h>
#include <grub/misc.h>
#include <grub/term.h>
#include <grub/loader.h>
#define min(a,b) (((a) < (b)) ? (a) : (b))
static void *hooktarget = 0;
extern grub_uint8_t grub_machine_mmaphook_start;
extern grub_uint8_t grub_machine_mmaphook_end;
extern grub_uint8_t grub_machine_mmaphook_int12;
extern grub_uint8_t grub_machine_mmaphook_int15;
static grub_uint16_t grub_machine_mmaphook_int12offset = 0;
static grub_uint16_t grub_machine_mmaphook_int12segment = 0;
extern grub_uint16_t grub_machine_mmaphook_int15offset;
extern grub_uint16_t grub_machine_mmaphook_int15segment;
extern grub_uint16_t grub_machine_mmaphook_mmap_num;
extern grub_uint16_t grub_machine_mmaphook_kblow;
extern grub_uint16_t grub_machine_mmaphook_kbin16mb;
extern grub_uint16_t grub_machine_mmaphook_64kbin4gb;
/* Helper for preboot. */
static int fill_hook (grub_uint64_t addr, grub_uint64_t size,
grub_memory_type_t type, void *data)
{
struct grub_e820_mmap_entry **hookmmapcur = data;
grub_dprintf ("mmap", "mmap chunk %llx-%llx:%x\n", addr, addr + size, type);
(*hookmmapcur)->addr = addr;
(*hookmmapcur)->len = size;
(*hookmmapcur)->type = type;
(*hookmmapcur)++;
return 0;
}
static grub_err_t
preboot (int noreturn __attribute__ ((unused)))
{
struct grub_e820_mmap_entry *hookmmap, *hookmmapcur;
if (! hooktarget)
return grub_error (GRUB_ERR_OUT_OF_MEMORY,
"no space is allocated for memory hook");
grub_dprintf ("mmap", "installing preboot handlers\n");
hookmmapcur = hookmmap = (struct grub_e820_mmap_entry *)
((grub_uint8_t *) hooktarget + (&grub_machine_mmaphook_end
- &grub_machine_mmaphook_start));
grub_mmap_iterate (fill_hook, &hookmmapcur);
grub_machine_mmaphook_mmap_num = hookmmapcur - hookmmap;
grub_machine_mmaphook_kblow = grub_mmap_get_lower () >> 10;
grub_machine_mmaphook_kbin16mb
= min (grub_mmap_get_upper (),0x3f00000ULL) >> 10;
grub_machine_mmaphook_64kbin4gb
= min (grub_mmap_get_post64 (), 0xfc000000ULL) >> 16;
/* Correct BDA. */
*((grub_uint16_t *) 0x413) = grub_mmap_get_lower () >> 10;
/* Save old interrupt handlers. */
grub_machine_mmaphook_int12offset = *((grub_uint16_t *) 0x48);
grub_machine_mmaphook_int12segment = *((grub_uint16_t *) 0x4a);
grub_machine_mmaphook_int15offset = *((grub_uint16_t *) 0x54);
grub_machine_mmaphook_int15segment = *((grub_uint16_t *) 0x56);
grub_dprintf ("mmap", "hooktarget = %p\n", hooktarget);
/* Install the interrupt handlers. */
grub_memcpy (hooktarget, &grub_machine_mmaphook_start,
&grub_machine_mmaphook_end - &grub_machine_mmaphook_start);
*((grub_uint16_t *) 0x4a) = ((grub_addr_t) hooktarget) >> 4;
*((grub_uint16_t *) 0x56) = ((grub_addr_t) hooktarget) >> 4;
*((grub_uint16_t *) 0x48) = &grub_machine_mmaphook_int12
- &grub_machine_mmaphook_start;
*((grub_uint16_t *) 0x54) = &grub_machine_mmaphook_int15
- &grub_machine_mmaphook_start;
return GRUB_ERR_NONE;
}
static grub_err_t
preboot_rest (void)
{
/* Restore old interrupt handlers. */
*((grub_uint16_t *) 0x48) = grub_machine_mmaphook_int12offset;
*((grub_uint16_t *) 0x4a) = grub_machine_mmaphook_int12segment;
*((grub_uint16_t *) 0x54) = grub_machine_mmaphook_int15offset;
*((grub_uint16_t *) 0x56) = grub_machine_mmaphook_int15segment;
return GRUB_ERR_NONE;
}
/* Helper for malloc_hook. */
static int
count_hook (grub_uint64_t addr __attribute__ ((unused)),
grub_uint64_t size __attribute__ ((unused)),
grub_memory_type_t type __attribute__ ((unused)), void *data)
{
int *regcount = data;
(*regcount)++;
return 0;
}
static grub_err_t
malloc_hook (void)
{
static int reentry = 0;
static int mmapregion = 0;
static int slots_available = 0;
int hooksize;
int regcount = 0;
if (reentry)
return GRUB_ERR_NONE;
grub_dprintf ("mmap", "registering\n");
grub_mmap_iterate (count_hook, ®count);
/* Mapping hook itself may introduce up to 2 additional regions. */
regcount += 2;
if (regcount <= slots_available)
return GRUB_ERR_NONE;
if (mmapregion)
{
grub_mmap_free_and_unregister (mmapregion);
mmapregion = 0;
hooktarget = 0;
}
hooksize = &grub_machine_mmaphook_end - &grub_machine_mmaphook_start
+ regcount * sizeof (struct grub_e820_mmap_entry);
/* Allocate an integer number of KiB. */
hooksize = ((hooksize - 1) | 0x3ff) + 1;
slots_available = (hooksize - (&grub_machine_mmaphook_end
- &grub_machine_mmaphook_start))
/ sizeof (struct grub_e820_mmap_entry);
reentry = 1;
hooktarget
= grub_mmap_malign_and_register (16, ALIGN_UP (hooksize, 16), &mmapregion,
GRUB_MEMORY_RESERVED,
GRUB_MMAP_MALLOC_LOW);
reentry = 0;
if (! hooktarget)
{
slots_available = 0;
return grub_error (GRUB_ERR_OUT_OF_MEMORY, "no space for mmap hook");
}
return GRUB_ERR_NONE;
}
grub_err_t
grub_machine_mmap_register (grub_uint64_t start __attribute__ ((unused)),
grub_uint64_t size __attribute__ ((unused)),
int type __attribute__ ((unused)),
int handle __attribute__ ((unused)))
{
grub_err_t err;
static struct grub_preboot *preb_handle = 0;
err = malloc_hook ();
if (err)
return err;
if (! preb_handle)
{
grub_dprintf ("mmap", "adding preboot\n");
preb_handle
= grub_loader_register_preboot_hook (preboot, preboot_rest,
GRUB_LOADER_PREBOOT_HOOK_PRIO_MEMORY);
if (! preb_handle)
return grub_errno;
}
return GRUB_ERR_NONE;
}
grub_err_t
grub_machine_mmap_unregister (int handle __attribute__ ((unused)))
{
return GRUB_ERR_NONE;
}
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