142 lines
3.5 KiB
C
Executable File
142 lines
3.5 KiB
C
Executable File
/*
|
|
* fake_mem.c
|
|
*
|
|
* Copyright (C) 2015 FUJITSU LIMITED
|
|
* Author: Taku Izumi <izumi.taku@jp.fujitsu.com>
|
|
*
|
|
* This code introduces new boot option named "efi_fake_mem"
|
|
* By specifying this parameter, you can add arbitrary attribute to
|
|
* specific memory range by updating original (firmware provided) EFI
|
|
* memmap.
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify it
|
|
* under the terms and conditions of the GNU General Public License,
|
|
* version 2, as published by the Free Software Foundation.
|
|
*
|
|
* This program is distributed in the hope 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
|
|
* this program; if not, see <http://www.gnu.org/licenses/>.
|
|
*
|
|
* The full GNU General Public License is included in this distribution in
|
|
* the file called "COPYING".
|
|
*/
|
|
|
|
#include <linux/kernel.h>
|
|
#include <linux/efi.h>
|
|
#include <linux/init.h>
|
|
#include <linux/memblock.h>
|
|
#include <linux/types.h>
|
|
#include <linux/sort.h>
|
|
#include <asm/efi.h>
|
|
|
|
#define EFI_MAX_FAKEMEM CONFIG_EFI_MAX_FAKE_MEM
|
|
|
|
static struct efi_mem_range fake_mems[EFI_MAX_FAKEMEM];
|
|
static int nr_fake_mem;
|
|
|
|
static int __init cmp_fake_mem(const void *x1, const void *x2)
|
|
{
|
|
const struct efi_mem_range *m1 = x1;
|
|
const struct efi_mem_range *m2 = x2;
|
|
|
|
if (m1->range.start < m2->range.start)
|
|
return -1;
|
|
if (m1->range.start > m2->range.start)
|
|
return 1;
|
|
return 0;
|
|
}
|
|
|
|
void __init efi_fake_memmap(void)
|
|
{
|
|
int new_nr_map = efi.memmap.nr_map;
|
|
efi_memory_desc_t *md;
|
|
phys_addr_t new_memmap_phy;
|
|
void *new_memmap;
|
|
int i;
|
|
|
|
if (!nr_fake_mem)
|
|
return;
|
|
|
|
/* count up the number of EFI memory descriptor */
|
|
for (i = 0; i < nr_fake_mem; i++) {
|
|
for_each_efi_memory_desc(md) {
|
|
struct range *r = &fake_mems[i].range;
|
|
|
|
new_nr_map += efi_memmap_split_count(md, r);
|
|
}
|
|
}
|
|
|
|
/* allocate memory for new EFI memmap */
|
|
new_memmap_phy = efi_memmap_alloc(new_nr_map);
|
|
if (!new_memmap_phy)
|
|
return;
|
|
|
|
/* create new EFI memmap */
|
|
new_memmap = early_memremap(new_memmap_phy,
|
|
efi.memmap.desc_size * new_nr_map);
|
|
if (!new_memmap) {
|
|
memblock_free(new_memmap_phy, efi.memmap.desc_size * new_nr_map);
|
|
return;
|
|
}
|
|
|
|
for (i = 0; i < nr_fake_mem; i++)
|
|
efi_memmap_insert(&efi.memmap, new_memmap, &fake_mems[i]);
|
|
|
|
/* swap into new EFI memmap */
|
|
early_memunmap(new_memmap, efi.memmap.desc_size * new_nr_map);
|
|
|
|
efi_memmap_install(new_memmap_phy, new_nr_map);
|
|
|
|
/* print new EFI memmap */
|
|
efi_print_memmap();
|
|
}
|
|
|
|
static int __init setup_fake_mem(char *p)
|
|
{
|
|
u64 start = 0, mem_size = 0, attribute = 0;
|
|
int i;
|
|
|
|
if (!p)
|
|
return -EINVAL;
|
|
|
|
while (*p != '\0') {
|
|
mem_size = memparse(p, &p);
|
|
if (*p == '@')
|
|
start = memparse(p+1, &p);
|
|
else
|
|
break;
|
|
|
|
if (*p == ':')
|
|
attribute = simple_strtoull(p+1, &p, 0);
|
|
else
|
|
break;
|
|
|
|
if (nr_fake_mem >= EFI_MAX_FAKEMEM)
|
|
break;
|
|
|
|
fake_mems[nr_fake_mem].range.start = start;
|
|
fake_mems[nr_fake_mem].range.end = start + mem_size - 1;
|
|
fake_mems[nr_fake_mem].attribute = attribute;
|
|
nr_fake_mem++;
|
|
|
|
if (*p == ',')
|
|
p++;
|
|
}
|
|
|
|
sort(fake_mems, nr_fake_mem, sizeof(struct efi_mem_range),
|
|
cmp_fake_mem, NULL);
|
|
|
|
for (i = 0; i < nr_fake_mem; i++)
|
|
pr_info("efi_fake_mem: add attr=0x%016llx to [mem 0x%016llx-0x%016llx]",
|
|
fake_mems[i].attribute, fake_mems[i].range.start,
|
|
fake_mems[i].range.end);
|
|
|
|
return *p == '\0' ? 0 : -EINVAL;
|
|
}
|
|
|
|
early_param("efi_fake_mem", setup_fake_mem);
|