]> git.proxmox.com Git - qemu.git/blob - memory_mapping.c
fw_cfg: Splash image loader can overrun a stack variable, fix
[qemu.git] / memory_mapping.c
1 /*
2 * QEMU memory mapping
3 *
4 * Copyright Fujitsu, Corp. 2011, 2012
5 *
6 * Authors:
7 * Wen Congyang <wency@cn.fujitsu.com>
8 *
9 * This work is licensed under the terms of the GNU GPL, version 2 or later.
10 * See the COPYING file in the top-level directory.
11 *
12 */
13
14 #include "cpu.h"
15 #include "exec/cpu-all.h"
16 #include "sysemu/memory_mapping.h"
17
18 static void memory_mapping_list_add_mapping_sorted(MemoryMappingList *list,
19 MemoryMapping *mapping)
20 {
21 MemoryMapping *p;
22
23 QTAILQ_FOREACH(p, &list->head, next) {
24 if (p->phys_addr >= mapping->phys_addr) {
25 QTAILQ_INSERT_BEFORE(p, mapping, next);
26 return;
27 }
28 }
29 QTAILQ_INSERT_TAIL(&list->head, mapping, next);
30 }
31
32 static void create_new_memory_mapping(MemoryMappingList *list,
33 hwaddr phys_addr,
34 hwaddr virt_addr,
35 ram_addr_t length)
36 {
37 MemoryMapping *memory_mapping;
38
39 memory_mapping = g_malloc(sizeof(MemoryMapping));
40 memory_mapping->phys_addr = phys_addr;
41 memory_mapping->virt_addr = virt_addr;
42 memory_mapping->length = length;
43 list->last_mapping = memory_mapping;
44 list->num++;
45 memory_mapping_list_add_mapping_sorted(list, memory_mapping);
46 }
47
48 static inline bool mapping_contiguous(MemoryMapping *map,
49 hwaddr phys_addr,
50 hwaddr virt_addr)
51 {
52 return phys_addr == map->phys_addr + map->length &&
53 virt_addr == map->virt_addr + map->length;
54 }
55
56 /*
57 * [map->phys_addr, map->phys_addr + map->length) and
58 * [phys_addr, phys_addr + length) have intersection?
59 */
60 static inline bool mapping_have_same_region(MemoryMapping *map,
61 hwaddr phys_addr,
62 ram_addr_t length)
63 {
64 return !(phys_addr + length < map->phys_addr ||
65 phys_addr >= map->phys_addr + map->length);
66 }
67
68 /*
69 * [map->phys_addr, map->phys_addr + map->length) and
70 * [phys_addr, phys_addr + length) have intersection. The virtual address in the
71 * intersection are the same?
72 */
73 static inline bool mapping_conflict(MemoryMapping *map,
74 hwaddr phys_addr,
75 hwaddr virt_addr)
76 {
77 return virt_addr - map->virt_addr != phys_addr - map->phys_addr;
78 }
79
80 /*
81 * [map->virt_addr, map->virt_addr + map->length) and
82 * [virt_addr, virt_addr + length) have intersection. And the physical address
83 * in the intersection are the same.
84 */
85 static inline void mapping_merge(MemoryMapping *map,
86 hwaddr virt_addr,
87 ram_addr_t length)
88 {
89 if (virt_addr < map->virt_addr) {
90 map->length += map->virt_addr - virt_addr;
91 map->virt_addr = virt_addr;
92 }
93
94 if ((virt_addr + length) >
95 (map->virt_addr + map->length)) {
96 map->length = virt_addr + length - map->virt_addr;
97 }
98 }
99
100 void memory_mapping_list_add_merge_sorted(MemoryMappingList *list,
101 hwaddr phys_addr,
102 hwaddr virt_addr,
103 ram_addr_t length)
104 {
105 MemoryMapping *memory_mapping, *last_mapping;
106
107 if (QTAILQ_EMPTY(&list->head)) {
108 create_new_memory_mapping(list, phys_addr, virt_addr, length);
109 return;
110 }
111
112 last_mapping = list->last_mapping;
113 if (last_mapping) {
114 if (mapping_contiguous(last_mapping, phys_addr, virt_addr)) {
115 last_mapping->length += length;
116 return;
117 }
118 }
119
120 QTAILQ_FOREACH(memory_mapping, &list->head, next) {
121 if (mapping_contiguous(memory_mapping, phys_addr, virt_addr)) {
122 memory_mapping->length += length;
123 list->last_mapping = memory_mapping;
124 return;
125 }
126
127 if (phys_addr + length < memory_mapping->phys_addr) {
128 /* create a new region before memory_mapping */
129 break;
130 }
131
132 if (mapping_have_same_region(memory_mapping, phys_addr, length)) {
133 if (mapping_conflict(memory_mapping, phys_addr, virt_addr)) {
134 continue;
135 }
136
137 /* merge this region into memory_mapping */
138 mapping_merge(memory_mapping, virt_addr, length);
139 list->last_mapping = memory_mapping;
140 return;
141 }
142 }
143
144 /* this region can not be merged into any existed memory mapping. */
145 create_new_memory_mapping(list, phys_addr, virt_addr, length);
146 }
147
148 void memory_mapping_list_free(MemoryMappingList *list)
149 {
150 MemoryMapping *p, *q;
151
152 QTAILQ_FOREACH_SAFE(p, &list->head, next, q) {
153 QTAILQ_REMOVE(&list->head, p, next);
154 g_free(p);
155 }
156
157 list->num = 0;
158 list->last_mapping = NULL;
159 }
160
161 void memory_mapping_list_init(MemoryMappingList *list)
162 {
163 list->num = 0;
164 list->last_mapping = NULL;
165 QTAILQ_INIT(&list->head);
166 }
167
168 static CPUArchState *find_paging_enabled_cpu(CPUArchState *start_cpu)
169 {
170 CPUArchState *env;
171
172 for (env = start_cpu; env != NULL; env = env->next_cpu) {
173 if (cpu_paging_enabled(env)) {
174 return env;
175 }
176 }
177
178 return NULL;
179 }
180
181 int qemu_get_guest_memory_mapping(MemoryMappingList *list)
182 {
183 CPUArchState *env, *first_paging_enabled_cpu;
184 RAMBlock *block;
185 ram_addr_t offset, length;
186 int ret;
187
188 first_paging_enabled_cpu = find_paging_enabled_cpu(first_cpu);
189 if (first_paging_enabled_cpu) {
190 for (env = first_paging_enabled_cpu; env != NULL; env = env->next_cpu) {
191 ret = cpu_get_memory_mapping(list, env);
192 if (ret < 0) {
193 return -1;
194 }
195 }
196 return 0;
197 }
198
199 /*
200 * If the guest doesn't use paging, the virtual address is equal to physical
201 * address.
202 */
203 QTAILQ_FOREACH(block, &ram_list.blocks, next) {
204 offset = block->offset;
205 length = block->length;
206 create_new_memory_mapping(list, offset, offset, length);
207 }
208
209 return 0;
210 }
211
212 void qemu_get_guest_simple_memory_mapping(MemoryMappingList *list)
213 {
214 RAMBlock *block;
215
216 QTAILQ_FOREACH(block, &ram_list.blocks, next) {
217 create_new_memory_mapping(list, block->offset, 0, block->length);
218 }
219 }
220
221 void memory_mapping_filter(MemoryMappingList *list, int64_t begin,
222 int64_t length)
223 {
224 MemoryMapping *cur, *next;
225
226 QTAILQ_FOREACH_SAFE(cur, &list->head, next, next) {
227 if (cur->phys_addr >= begin + length ||
228 cur->phys_addr + cur->length <= begin) {
229 QTAILQ_REMOVE(&list->head, cur, next);
230 list->num--;
231 continue;
232 }
233
234 if (cur->phys_addr < begin) {
235 cur->length -= begin - cur->phys_addr;
236 if (cur->virt_addr) {
237 cur->virt_addr += begin - cur->phys_addr;
238 }
239 cur->phys_addr = begin;
240 }
241
242 if (cur->phys_addr + cur->length > begin + length) {
243 cur->length -= cur->phys_addr + cur->length - begin - length;
244 }
245 }
246 }