1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
|
/*
* 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
struct fake_mem {
struct range range;
u64 attribute;
};
static struct fake_mem fake_mems[EFI_MAX_FAKEMEM];
static int nr_fake_mem;
static int __init cmp_fake_mem(const void *x1, const void *x2)
{
const struct fake_mem *m1 = x1;
const struct fake_mem *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)
{
u64 start, end, m_start, m_end, m_attr;
struct efi_memory_map_data data;
int new_nr_map = efi.memmap.nr_map;
efi_memory_desc_t *md;
phys_addr_t new_memmap_phy;
void *new_memmap;
void *old, *new;
int i;
if (!nr_fake_mem)
return;
/* count up the number of EFI memory descriptor */
for_each_efi_memory_desc(md) {
start = md->phys_addr;
end = start + (md->num_pages << EFI_PAGE_SHIFT) - 1;
for (i = 0; i < nr_fake_mem; i++) {
/* modifying range */
m_start = fake_mems[i].range.start;
m_end = fake_mems[i].range.end;
if (m_start <= start) {
/* split into 2 parts */
if (start < m_end && m_end < end)
new_nr_map++;
}
if (start < m_start && m_start < end) {
/* split into 3 parts */
if (m_end < end)
new_nr_map += 2;
/* split into 2 parts */
if (end <= m_end)
new_nr_map++;
}
}
}
/* allocate memory for new EFI memmap */
new_memmap_phy = memblock_alloc(efi.memmap.desc_size * new_nr_map,
PAGE_SIZE);
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 (old = efi.memmap.map, new = new_memmap;
old < efi.memmap.map_end;
old += efi.memmap.desc_size, new += efi.memmap.desc_size) {
/* copy original EFI memory descriptor */
memcpy(new, old, efi.memmap.desc_size);
md = new;
start = md->phys_addr;
end = md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT) - 1;
for (i = 0; i < nr_fake_mem; i++) {
/* modifying range */
m_start = fake_mems[i].range.start;
m_end = fake_mems[i].range.end;
m_attr = fake_mems[i].attribute;
if (m_start <= start && end <= m_end)
md->attribute |= m_attr;
if (m_start <= start &&
(start < m_end && m_end < end)) {
/* first part */
md->attribute |= m_attr;
md->num_pages = (m_end - md->phys_addr + 1) >>
EFI_PAGE_SHIFT;
/* latter part */
new += efi.memmap.desc_size;
memcpy(new, old, efi.memmap.desc_size);
md = new;
md->phys_addr = m_end + 1;
md->num_pages = (end - md->phys_addr + 1) >>
EFI_PAGE_SHIFT;
}
if ((start < m_start && m_start < end) && m_end < end) {
/* first part */
md->num_pages = (m_start - md->phys_addr) >>
EFI_PAGE_SHIFT;
/* middle part */
new += efi.memmap.desc_size;
memcpy(new, old, efi.memmap.desc_size);
md = new;
md->attribute |= m_attr;
md->phys_addr = m_start;
md->num_pages = (m_end - m_start + 1) >>
EFI_PAGE_SHIFT;
/* last part */
new += efi.memmap.desc_size;
memcpy(new, old, efi.memmap.desc_size);
md = new;
md->phys_addr = m_end + 1;
md->num_pages = (end - m_end) >>
EFI_PAGE_SHIFT;
}
if ((start < m_start && m_start < end) &&
(end <= m_end)) {
/* first part */
md->num_pages = (m_start - md->phys_addr) >>
EFI_PAGE_SHIFT;
/* latter part */
new += efi.memmap.desc_size;
memcpy(new, old, efi.memmap.desc_size);
md = new;
md->phys_addr = m_start;
md->num_pages = (end - md->phys_addr + 1) >>
EFI_PAGE_SHIFT;
md->attribute |= m_attr;
}
}
}
/* swap into new EFI memmap */
early_memunmap(new_memmap, efi.memmap.desc_size * new_nr_map);
efi_memmap_unmap();
data.phys_map = new_memmap_phy;
data.size = efi.memmap.desc_size * new_nr_map;
data.desc_version = efi.memmap.desc_version;
data.desc_size = efi.memmap.desc_size;
efi_memmap_init_early(&data);
/* 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 fake_mem),
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);
|
