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 }