summaryrefslogtreecommitdiff
path: root/memory_mapping.c
blob: 7b69801cb822ce23f946b899dccf08b131cb9f5e (plain)
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
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
/*
 * QEMU memory mapping
 *
 * Copyright Fujitsu, Corp. 2011, 2012
 *
 * Authors:
 *     Wen Congyang <wency@cn.fujitsu.com>
 *
 * This work is licensed under the terms of the GNU GPL, version 2 or later.
 * See the COPYING file in the top-level directory.
 *
 */

#include <glib.h>

#include "cpu.h"
#include "exec/cpu-all.h"
#include "sysemu/memory_mapping.h"
#include "exec/memory.h"
#include "exec/address-spaces.h"

//#define DEBUG_GUEST_PHYS_REGION_ADD

static void memory_mapping_list_add_mapping_sorted(MemoryMappingList *list,
                                                   MemoryMapping *mapping)
{
    MemoryMapping *p;

    QTAILQ_FOREACH(p, &list->head, next) {
        if (p->phys_addr >= mapping->phys_addr) {
            QTAILQ_INSERT_BEFORE(p, mapping, next);
            return;
        }
    }
    QTAILQ_INSERT_TAIL(&list->head, mapping, next);
}

static void create_new_memory_mapping(MemoryMappingList *list,
                                      hwaddr phys_addr,
                                      hwaddr virt_addr,
                                      ram_addr_t length)
{
    MemoryMapping *memory_mapping;

    memory_mapping = g_malloc(sizeof(MemoryMapping));
    memory_mapping->phys_addr = phys_addr;
    memory_mapping->virt_addr = virt_addr;
    memory_mapping->length = length;
    list->last_mapping = memory_mapping;
    list->num++;
    memory_mapping_list_add_mapping_sorted(list, memory_mapping);
}

static inline bool mapping_contiguous(MemoryMapping *map,
                                      hwaddr phys_addr,
                                      hwaddr virt_addr)
{
    return phys_addr == map->phys_addr + map->length &&
           virt_addr == map->virt_addr + map->length;
}

/*
 * [map->phys_addr, map->phys_addr + map->length) and
 * [phys_addr, phys_addr + length) have intersection?
 */
static inline bool mapping_have_same_region(MemoryMapping *map,
                                            hwaddr phys_addr,
                                            ram_addr_t length)
{
    return !(phys_addr + length < map->phys_addr ||
             phys_addr >= map->phys_addr + map->length);
}

/*
 * [map->phys_addr, map->phys_addr + map->length) and
 * [phys_addr, phys_addr + length) have intersection. The virtual address in the
 * intersection are the same?
 */
static inline bool mapping_conflict(MemoryMapping *map,
                                    hwaddr phys_addr,
                                    hwaddr virt_addr)
{
    return virt_addr - map->virt_addr != phys_addr - map->phys_addr;
}

/*
 * [map->virt_addr, map->virt_addr + map->length) and
 * [virt_addr, virt_addr + length) have intersection. And the physical address
 * in the intersection are the same.
 */
static inline void mapping_merge(MemoryMapping *map,
                                 hwaddr virt_addr,
                                 ram_addr_t length)
{
    if (virt_addr < map->virt_addr) {
        map->length += map->virt_addr - virt_addr;
        map->virt_addr = virt_addr;
    }

    if ((virt_addr + length) >
        (map->virt_addr + map->length)) {
        map->length = virt_addr + length - map->virt_addr;
    }
}

void memory_mapping_list_add_merge_sorted(MemoryMappingList *list,
                                          hwaddr phys_addr,
                                          hwaddr virt_addr,
                                          ram_addr_t length)
{
    MemoryMapping *memory_mapping, *last_mapping;

    if (QTAILQ_EMPTY(&list->head)) {
        create_new_memory_mapping(list, phys_addr, virt_addr, length);
        return;
    }

    last_mapping = list->last_mapping;
    if (last_mapping) {
        if (mapping_contiguous(last_mapping, phys_addr, virt_addr)) {
            last_mapping->length += length;
            return;
        }
    }

    QTAILQ_FOREACH(memory_mapping, &list->head, next) {
        if (mapping_contiguous(memory_mapping, phys_addr, virt_addr)) {
            memory_mapping->length += length;
            list->last_mapping = memory_mapping;
            return;
        }

        if (phys_addr + length < memory_mapping->phys_addr) {
            /* create a new region before memory_mapping */
            break;
        }

        if (mapping_have_same_region(memory_mapping, phys_addr, length)) {
            if (mapping_conflict(memory_mapping, phys_addr, virt_addr)) {
                continue;
            }

            /* merge this region into memory_mapping */
            mapping_merge(memory_mapping, virt_addr, length);
            list->last_mapping = memory_mapping;
            return;
        }
    }

    /* this region can not be merged into any existed memory mapping. */
    create_new_memory_mapping(list, phys_addr, virt_addr, length);
}

void memory_mapping_list_free(MemoryMappingList *list)
{
    MemoryMapping *p, *q;

    QTAILQ_FOREACH_SAFE(p, &list->head, next, q) {
        QTAILQ_REMOVE(&list->head, p, next);
        g_free(p);
    }

    list->num = 0;
    list->last_mapping = NULL;
}

void memory_mapping_list_init(MemoryMappingList *list)
{
    list->num = 0;
    list->last_mapping = NULL;
    QTAILQ_INIT(&list->head);
}

void guest_phys_blocks_free(GuestPhysBlockList *list)
{
    GuestPhysBlock *p, *q;

    QTAILQ_FOREACH_SAFE(p, &list->head, next, q) {
        QTAILQ_REMOVE(&list->head, p, next);
        g_free(p);
    }
    list->num = 0;
}

void guest_phys_blocks_init(GuestPhysBlockList *list)
{
    list->num = 0;
    QTAILQ_INIT(&list->head);
}

typedef struct GuestPhysListener {
    GuestPhysBlockList *list;
    MemoryListener listener;
} GuestPhysListener;

static void guest_phys_blocks_region_add(MemoryListener *listener,
                                         MemoryRegionSection *section)
{
    GuestPhysListener *g;
    uint64_t section_size;
    hwaddr target_start, target_end;
    uint8_t *host_addr;
    GuestPhysBlock *predecessor;

    /* we only care about RAM */
    if (!memory_region_is_ram(section->mr) ||
        memory_region_is_skip_dump(section->mr)) {
        return;
    }

    g            = container_of(listener, GuestPhysListener, listener);
    section_size = int128_get64(section->size);
    target_start = section->offset_within_address_space;
    target_end   = target_start + section_size;
    host_addr    = memory_region_get_ram_ptr(section->mr) +
                   section->offset_within_region;
    predecessor  = NULL;

    /* find continuity in guest physical address space */
    if (!QTAILQ_EMPTY(&g->list->head)) {
        hwaddr predecessor_size;

        predecessor = QTAILQ_LAST(&g->list->head, GuestPhysBlockHead);
        predecessor_size = predecessor->target_end - predecessor->target_start;

        /* the memory API guarantees monotonically increasing traversal */
        g_assert(predecessor->target_end <= target_start);

        /* we want continuity in both guest-physical and host-virtual memory */
        if (predecessor->target_end < target_start ||
            predecessor->host_addr + predecessor_size != host_addr) {
            predecessor = NULL;
        }
    }

    if (predecessor == NULL) {
        /* isolated mapping, allocate it and add it to the list */
        GuestPhysBlock *block = g_malloc0(sizeof *block);

        block->target_start = target_start;
        block->target_end   = target_end;
        block->host_addr    = host_addr;

        QTAILQ_INSERT_TAIL(&g->list->head, block, next);
        ++g->list->num;
    } else {
        /* expand predecessor until @target_end; predecessor's start doesn't
         * change
         */
        predecessor->target_end = target_end;
    }

#ifdef DEBUG_GUEST_PHYS_REGION_ADD
    fprintf(stderr, "%s: target_start=" TARGET_FMT_plx " target_end="
            TARGET_FMT_plx ": %s (count: %u)\n", __FUNCTION__, target_start,
            target_end, predecessor ? "joined" : "added", g->list->num);
#endif
}

void guest_phys_blocks_append(GuestPhysBlockList *list)
{
    GuestPhysListener g = { 0 };

    g.list = list;
    g.listener.region_add = &guest_phys_blocks_region_add;
    memory_listener_register(&g.listener, &address_space_memory);
    memory_listener_unregister(&g.listener);
}

static CPUState *find_paging_enabled_cpu(CPUState *start_cpu)
{
    CPUState *cpu;

    CPU_FOREACH(cpu) {
        if (cpu_paging_enabled(cpu)) {
            return cpu;
        }
    }

    return NULL;
}

void qemu_get_guest_memory_mapping(MemoryMappingList *list,
                                   const GuestPhysBlockList *guest_phys_blocks,
                                   Error **errp)
{
    CPUState *cpu, *first_paging_enabled_cpu;
    GuestPhysBlock *block;
    ram_addr_t offset, length;

    first_paging_enabled_cpu = find_paging_enabled_cpu(first_cpu);
    if (first_paging_enabled_cpu) {
        for (cpu = first_paging_enabled_cpu; cpu != NULL;
             cpu = CPU_NEXT(cpu)) {
            Error *err = NULL;
            cpu_get_memory_mapping(cpu, list, &err);
            if (err) {
                error_propagate(errp, err);
                return;
            }
        }
        return;
    }

    /*
     * If the guest doesn't use paging, the virtual address is equal to physical
     * address.
     */
    QTAILQ_FOREACH(block, &guest_phys_blocks->head, next) {
        offset = block->target_start;
        length = block->target_end - block->target_start;
        create_new_memory_mapping(list, offset, offset, length);
    }
}

void qemu_get_guest_simple_memory_mapping(MemoryMappingList *list,
                                   const GuestPhysBlockList *guest_phys_blocks)
{
    GuestPhysBlock *block;

    QTAILQ_FOREACH(block, &guest_phys_blocks->head, next) {
        create_new_memory_mapping(list, block->target_start, 0,
                                  block->target_end - block->target_start);
    }
}

void memory_mapping_filter(MemoryMappingList *list, int64_t begin,
                           int64_t length)
{
    MemoryMapping *cur, *next;

    QTAILQ_FOREACH_SAFE(cur, &list->head, next, next) {
        if (cur->phys_addr >= begin + length ||
            cur->phys_addr + cur->length <= begin) {
            QTAILQ_REMOVE(&list->head, cur, next);
            list->num--;
            continue;
        }

        if (cur->phys_addr < begin) {
            cur->length -= begin - cur->phys_addr;
            if (cur->virt_addr) {
                cur->virt_addr += begin - cur->phys_addr;
            }
            cur->phys_addr = begin;
        }

        if (cur->phys_addr + cur->length > begin + length) {
            cur->length -= cur->phys_addr + cur->length - begin - length;
        }
    }
}