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[kvmfornfv.git] / qemu / 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 <glib.h>
15
16 #include "qemu-common.h"
17 #include "cpu.h"
18 #include "sysemu/memory_mapping.h"
19 #include "exec/memory.h"
20 #include "exec/address-spaces.h"
21
22 //#define DEBUG_GUEST_PHYS_REGION_ADD
23
24 static void memory_mapping_list_add_mapping_sorted(MemoryMappingList *list,
25                                                    MemoryMapping *mapping)
26 {
27     MemoryMapping *p;
28
29     QTAILQ_FOREACH(p, &list->head, next) {
30         if (p->phys_addr >= mapping->phys_addr) {
31             QTAILQ_INSERT_BEFORE(p, mapping, next);
32             return;
33         }
34     }
35     QTAILQ_INSERT_TAIL(&list->head, mapping, next);
36 }
37
38 static void create_new_memory_mapping(MemoryMappingList *list,
39                                       hwaddr phys_addr,
40                                       hwaddr virt_addr,
41                                       ram_addr_t length)
42 {
43     MemoryMapping *memory_mapping;
44
45     memory_mapping = g_malloc(sizeof(MemoryMapping));
46     memory_mapping->phys_addr = phys_addr;
47     memory_mapping->virt_addr = virt_addr;
48     memory_mapping->length = length;
49     list->last_mapping = memory_mapping;
50     list->num++;
51     memory_mapping_list_add_mapping_sorted(list, memory_mapping);
52 }
53
54 static inline bool mapping_contiguous(MemoryMapping *map,
55                                       hwaddr phys_addr,
56                                       hwaddr virt_addr)
57 {
58     return phys_addr == map->phys_addr + map->length &&
59            virt_addr == map->virt_addr + map->length;
60 }
61
62 /*
63  * [map->phys_addr, map->phys_addr + map->length) and
64  * [phys_addr, phys_addr + length) have intersection?
65  */
66 static inline bool mapping_have_same_region(MemoryMapping *map,
67                                             hwaddr phys_addr,
68                                             ram_addr_t length)
69 {
70     return !(phys_addr + length < map->phys_addr ||
71              phys_addr >= map->phys_addr + map->length);
72 }
73
74 /*
75  * [map->phys_addr, map->phys_addr + map->length) and
76  * [phys_addr, phys_addr + length) have intersection. The virtual address in the
77  * intersection are the same?
78  */
79 static inline bool mapping_conflict(MemoryMapping *map,
80                                     hwaddr phys_addr,
81                                     hwaddr virt_addr)
82 {
83     return virt_addr - map->virt_addr != phys_addr - map->phys_addr;
84 }
85
86 /*
87  * [map->virt_addr, map->virt_addr + map->length) and
88  * [virt_addr, virt_addr + length) have intersection. And the physical address
89  * in the intersection are the same.
90  */
91 static inline void mapping_merge(MemoryMapping *map,
92                                  hwaddr virt_addr,
93                                  ram_addr_t length)
94 {
95     if (virt_addr < map->virt_addr) {
96         map->length += map->virt_addr - virt_addr;
97         map->virt_addr = virt_addr;
98     }
99
100     if ((virt_addr + length) >
101         (map->virt_addr + map->length)) {
102         map->length = virt_addr + length - map->virt_addr;
103     }
104 }
105
106 void memory_mapping_list_add_merge_sorted(MemoryMappingList *list,
107                                           hwaddr phys_addr,
108                                           hwaddr virt_addr,
109                                           ram_addr_t length)
110 {
111     MemoryMapping *memory_mapping, *last_mapping;
112
113     if (QTAILQ_EMPTY(&list->head)) {
114         create_new_memory_mapping(list, phys_addr, virt_addr, length);
115         return;
116     }
117
118     last_mapping = list->last_mapping;
119     if (last_mapping) {
120         if (mapping_contiguous(last_mapping, phys_addr, virt_addr)) {
121             last_mapping->length += length;
122             return;
123         }
124     }
125
126     QTAILQ_FOREACH(memory_mapping, &list->head, next) {
127         if (mapping_contiguous(memory_mapping, phys_addr, virt_addr)) {
128             memory_mapping->length += length;
129             list->last_mapping = memory_mapping;
130             return;
131         }
132
133         if (phys_addr + length < memory_mapping->phys_addr) {
134             /* create a new region before memory_mapping */
135             break;
136         }
137
138         if (mapping_have_same_region(memory_mapping, phys_addr, length)) {
139             if (mapping_conflict(memory_mapping, phys_addr, virt_addr)) {
140                 continue;
141             }
142
143             /* merge this region into memory_mapping */
144             mapping_merge(memory_mapping, virt_addr, length);
145             list->last_mapping = memory_mapping;
146             return;
147         }
148     }
149
150     /* this region can not be merged into any existed memory mapping. */
151     create_new_memory_mapping(list, phys_addr, virt_addr, length);
152 }
153
154 void memory_mapping_list_free(MemoryMappingList *list)
155 {
156     MemoryMapping *p, *q;
157
158     QTAILQ_FOREACH_SAFE(p, &list->head, next, q) {
159         QTAILQ_REMOVE(&list->head, p, next);
160         g_free(p);
161     }
162
163     list->num = 0;
164     list->last_mapping = NULL;
165 }
166
167 void memory_mapping_list_init(MemoryMappingList *list)
168 {
169     list->num = 0;
170     list->last_mapping = NULL;
171     QTAILQ_INIT(&list->head);
172 }
173
174 void guest_phys_blocks_free(GuestPhysBlockList *list)
175 {
176     GuestPhysBlock *p, *q;
177
178     QTAILQ_FOREACH_SAFE(p, &list->head, next, q) {
179         QTAILQ_REMOVE(&list->head, p, next);
180         g_free(p);
181     }
182     list->num = 0;
183 }
184
185 void guest_phys_blocks_init(GuestPhysBlockList *list)
186 {
187     list->num = 0;
188     QTAILQ_INIT(&list->head);
189 }
190
191 typedef struct GuestPhysListener {
192     GuestPhysBlockList *list;
193     MemoryListener listener;
194 } GuestPhysListener;
195
196 static void guest_phys_blocks_region_add(MemoryListener *listener,
197                                          MemoryRegionSection *section)
198 {
199     GuestPhysListener *g;
200     uint64_t section_size;
201     hwaddr target_start, target_end;
202     uint8_t *host_addr;
203     GuestPhysBlock *predecessor;
204
205     /* we only care about RAM */
206     if (!memory_region_is_ram(section->mr) ||
207         memory_region_is_skip_dump(section->mr)) {
208         return;
209     }
210
211     g            = container_of(listener, GuestPhysListener, listener);
212     section_size = int128_get64(section->size);
213     target_start = section->offset_within_address_space;
214     target_end   = target_start + section_size;
215     host_addr    = memory_region_get_ram_ptr(section->mr) +
216                    section->offset_within_region;
217     predecessor  = NULL;
218
219     /* find continuity in guest physical address space */
220     if (!QTAILQ_EMPTY(&g->list->head)) {
221         hwaddr predecessor_size;
222
223         predecessor = QTAILQ_LAST(&g->list->head, GuestPhysBlockHead);
224         predecessor_size = predecessor->target_end - predecessor->target_start;
225
226         /* the memory API guarantees monotonically increasing traversal */
227         g_assert(predecessor->target_end <= target_start);
228
229         /* we want continuity in both guest-physical and host-virtual memory */
230         if (predecessor->target_end < target_start ||
231             predecessor->host_addr + predecessor_size != host_addr) {
232             predecessor = NULL;
233         }
234     }
235
236     if (predecessor == NULL) {
237         /* isolated mapping, allocate it and add it to the list */
238         GuestPhysBlock *block = g_malloc0(sizeof *block);
239
240         block->target_start = target_start;
241         block->target_end   = target_end;
242         block->host_addr    = host_addr;
243
244         QTAILQ_INSERT_TAIL(&g->list->head, block, next);
245         ++g->list->num;
246     } else {
247         /* expand predecessor until @target_end; predecessor's start doesn't
248          * change
249          */
250         predecessor->target_end = target_end;
251     }
252
253 #ifdef DEBUG_GUEST_PHYS_REGION_ADD
254     fprintf(stderr, "%s: target_start=" TARGET_FMT_plx " target_end="
255             TARGET_FMT_plx ": %s (count: %u)\n", __FUNCTION__, target_start,
256             target_end, predecessor ? "joined" : "added", g->list->num);
257 #endif
258 }
259
260 void guest_phys_blocks_append(GuestPhysBlockList *list)
261 {
262     GuestPhysListener g = { 0 };
263
264     g.list = list;
265     g.listener.region_add = &guest_phys_blocks_region_add;
266     memory_listener_register(&g.listener, &address_space_memory);
267     memory_listener_unregister(&g.listener);
268 }
269
270 static CPUState *find_paging_enabled_cpu(CPUState *start_cpu)
271 {
272     CPUState *cpu;
273
274     CPU_FOREACH(cpu) {
275         if (cpu_paging_enabled(cpu)) {
276             return cpu;
277         }
278     }
279
280     return NULL;
281 }
282
283 void qemu_get_guest_memory_mapping(MemoryMappingList *list,
284                                    const GuestPhysBlockList *guest_phys_blocks,
285                                    Error **errp)
286 {
287     CPUState *cpu, *first_paging_enabled_cpu;
288     GuestPhysBlock *block;
289     ram_addr_t offset, length;
290
291     first_paging_enabled_cpu = find_paging_enabled_cpu(first_cpu);
292     if (first_paging_enabled_cpu) {
293         for (cpu = first_paging_enabled_cpu; cpu != NULL;
294              cpu = CPU_NEXT(cpu)) {
295             Error *err = NULL;
296             cpu_get_memory_mapping(cpu, list, &err);
297             if (err) {
298                 error_propagate(errp, err);
299                 return;
300             }
301         }
302         return;
303     }
304
305     /*
306      * If the guest doesn't use paging, the virtual address is equal to physical
307      * address.
308      */
309     QTAILQ_FOREACH(block, &guest_phys_blocks->head, next) {
310         offset = block->target_start;
311         length = block->target_end - block->target_start;
312         create_new_memory_mapping(list, offset, offset, length);
313     }
314 }
315
316 void qemu_get_guest_simple_memory_mapping(MemoryMappingList *list,
317                                    const GuestPhysBlockList *guest_phys_blocks)
318 {
319     GuestPhysBlock *block;
320
321     QTAILQ_FOREACH(block, &guest_phys_blocks->head, next) {
322         create_new_memory_mapping(list, block->target_start, 0,
323                                   block->target_end - block->target_start);
324     }
325 }
326
327 void memory_mapping_filter(MemoryMappingList *list, int64_t begin,
328                            int64_t length)
329 {
330     MemoryMapping *cur, *next;
331
332     QTAILQ_FOREACH_SAFE(cur, &list->head, next, next) {
333         if (cur->phys_addr >= begin + length ||
334             cur->phys_addr + cur->length <= begin) {
335             QTAILQ_REMOVE(&list->head, cur, next);
336             list->num--;
337             continue;
338         }
339
340         if (cur->phys_addr < begin) {
341             cur->length -= begin - cur->phys_addr;
342             if (cur->virt_addr) {
343                 cur->virt_addr += begin - cur->phys_addr;
344             }
345             cur->phys_addr = begin;
346         }
347
348         if (cur->phys_addr + cur->length > begin + length) {
349             cur->length -= cur->phys_addr + cur->length - begin - length;
350         }
351     }
352 }