]> git.proxmox.com Git - qemu.git/blob - xen-mapcache.c
msi: Guard msi/msix_write_config with msi_present
[qemu.git] / xen-mapcache.c
1 /*
2 * Copyright (C) 2011 Citrix Ltd.
3 *
4 * This work is licensed under the terms of the GNU GPL, version 2. See
5 * the COPYING file in the top-level directory.
6 *
7 * Contributions after 2012-01-13 are licensed under the terms of the
8 * GNU GPL, version 2 or (at your option) any later version.
9 */
10
11 #include "config.h"
12
13 #include <sys/resource.h>
14
15 #include "hw/xen_backend.h"
16 #include "blockdev.h"
17 #include "bitmap.h"
18
19 #include <xen/hvm/params.h>
20 #include <sys/mman.h>
21
22 #include "xen-mapcache.h"
23 #include "trace.h"
24
25
26 //#define MAPCACHE_DEBUG
27
28 #ifdef MAPCACHE_DEBUG
29 # define DPRINTF(fmt, ...) do { \
30 fprintf(stderr, "xen_mapcache: " fmt, ## __VA_ARGS__); \
31 } while (0)
32 #else
33 # define DPRINTF(fmt, ...) do { } while (0)
34 #endif
35
36 #if defined(__i386__)
37 # define MCACHE_BUCKET_SHIFT 16
38 # define MCACHE_MAX_SIZE (1UL<<31) /* 2GB Cap */
39 #elif defined(__x86_64__)
40 # define MCACHE_BUCKET_SHIFT 20
41 # define MCACHE_MAX_SIZE (1UL<<35) /* 32GB Cap */
42 #endif
43 #define MCACHE_BUCKET_SIZE (1UL << MCACHE_BUCKET_SHIFT)
44
45 /* This is the size of the virtual address space reserve to QEMU that will not
46 * be use by MapCache.
47 * From empirical tests I observed that qemu use 75MB more than the
48 * max_mcache_size.
49 */
50 #define NON_MCACHE_MEMORY_SIZE (80 * 1024 * 1024)
51
52 #define mapcache_lock() ((void)0)
53 #define mapcache_unlock() ((void)0)
54
55 typedef struct MapCacheEntry {
56 target_phys_addr_t paddr_index;
57 uint8_t *vaddr_base;
58 unsigned long *valid_mapping;
59 uint8_t lock;
60 target_phys_addr_t size;
61 struct MapCacheEntry *next;
62 } MapCacheEntry;
63
64 typedef struct MapCacheRev {
65 uint8_t *vaddr_req;
66 target_phys_addr_t paddr_index;
67 target_phys_addr_t size;
68 QTAILQ_ENTRY(MapCacheRev) next;
69 } MapCacheRev;
70
71 typedef struct MapCache {
72 MapCacheEntry *entry;
73 unsigned long nr_buckets;
74 QTAILQ_HEAD(map_cache_head, MapCacheRev) locked_entries;
75
76 /* For most cases (>99.9%), the page address is the same. */
77 target_phys_addr_t last_address_index;
78 uint8_t *last_address_vaddr;
79 unsigned long max_mcache_size;
80 unsigned int mcache_bucket_shift;
81
82 phys_offset_to_gaddr_t phys_offset_to_gaddr;
83 void *opaque;
84 } MapCache;
85
86 static MapCache *mapcache;
87
88 static inline int test_bits(int nr, int size, const unsigned long *addr)
89 {
90 unsigned long res = find_next_zero_bit(addr, size + nr, nr);
91 if (res >= nr + size)
92 return 1;
93 else
94 return 0;
95 }
96
97 void xen_map_cache_init(phys_offset_to_gaddr_t f, void *opaque)
98 {
99 unsigned long size;
100 struct rlimit rlimit_as;
101
102 mapcache = g_malloc0(sizeof (MapCache));
103
104 mapcache->phys_offset_to_gaddr = f;
105 mapcache->opaque = opaque;
106
107 QTAILQ_INIT(&mapcache->locked_entries);
108 mapcache->last_address_index = -1;
109
110 if (geteuid() == 0) {
111 rlimit_as.rlim_cur = RLIM_INFINITY;
112 rlimit_as.rlim_max = RLIM_INFINITY;
113 mapcache->max_mcache_size = MCACHE_MAX_SIZE;
114 } else {
115 getrlimit(RLIMIT_AS, &rlimit_as);
116 rlimit_as.rlim_cur = rlimit_as.rlim_max;
117
118 if (rlimit_as.rlim_max != RLIM_INFINITY) {
119 fprintf(stderr, "Warning: QEMU's maximum size of virtual"
120 " memory is not infinity.\n");
121 }
122 if (rlimit_as.rlim_max < MCACHE_MAX_SIZE + NON_MCACHE_MEMORY_SIZE) {
123 mapcache->max_mcache_size = rlimit_as.rlim_max -
124 NON_MCACHE_MEMORY_SIZE;
125 } else {
126 mapcache->max_mcache_size = MCACHE_MAX_SIZE;
127 }
128 }
129
130 setrlimit(RLIMIT_AS, &rlimit_as);
131
132 mapcache->nr_buckets =
133 (((mapcache->max_mcache_size >> XC_PAGE_SHIFT) +
134 (1UL << (MCACHE_BUCKET_SHIFT - XC_PAGE_SHIFT)) - 1) >>
135 (MCACHE_BUCKET_SHIFT - XC_PAGE_SHIFT));
136
137 size = mapcache->nr_buckets * sizeof (MapCacheEntry);
138 size = (size + XC_PAGE_SIZE - 1) & ~(XC_PAGE_SIZE - 1);
139 DPRINTF("%s, nr_buckets = %lx size %lu\n", __func__,
140 mapcache->nr_buckets, size);
141 mapcache->entry = g_malloc0(size);
142 }
143
144 static void xen_remap_bucket(MapCacheEntry *entry,
145 target_phys_addr_t size,
146 target_phys_addr_t address_index)
147 {
148 uint8_t *vaddr_base;
149 xen_pfn_t *pfns;
150 int *err;
151 unsigned int i;
152 target_phys_addr_t nb_pfn = size >> XC_PAGE_SHIFT;
153
154 trace_xen_remap_bucket(address_index);
155
156 pfns = g_malloc0(nb_pfn * sizeof (xen_pfn_t));
157 err = g_malloc0(nb_pfn * sizeof (int));
158
159 if (entry->vaddr_base != NULL) {
160 if (munmap(entry->vaddr_base, entry->size) != 0) {
161 perror("unmap fails");
162 exit(-1);
163 }
164 }
165 if (entry->valid_mapping != NULL) {
166 g_free(entry->valid_mapping);
167 entry->valid_mapping = NULL;
168 }
169
170 for (i = 0; i < nb_pfn; i++) {
171 pfns[i] = (address_index << (MCACHE_BUCKET_SHIFT-XC_PAGE_SHIFT)) + i;
172 }
173
174 vaddr_base = xc_map_foreign_bulk(xen_xc, xen_domid, PROT_READ|PROT_WRITE,
175 pfns, err, nb_pfn);
176 if (vaddr_base == NULL) {
177 perror("xc_map_foreign_bulk");
178 exit(-1);
179 }
180
181 entry->vaddr_base = vaddr_base;
182 entry->paddr_index = address_index;
183 entry->size = size;
184 entry->valid_mapping = (unsigned long *) g_malloc0(sizeof(unsigned long) *
185 BITS_TO_LONGS(size >> XC_PAGE_SHIFT));
186
187 bitmap_zero(entry->valid_mapping, nb_pfn);
188 for (i = 0; i < nb_pfn; i++) {
189 if (!err[i]) {
190 bitmap_set(entry->valid_mapping, i, 1);
191 }
192 }
193
194 g_free(pfns);
195 g_free(err);
196 }
197
198 uint8_t *xen_map_cache(target_phys_addr_t phys_addr, target_phys_addr_t size,
199 uint8_t lock)
200 {
201 MapCacheEntry *entry, *pentry = NULL;
202 target_phys_addr_t address_index;
203 target_phys_addr_t address_offset;
204 target_phys_addr_t __size = size;
205 bool translated = false;
206
207 tryagain:
208 address_index = phys_addr >> MCACHE_BUCKET_SHIFT;
209 address_offset = phys_addr & (MCACHE_BUCKET_SIZE - 1);
210
211 trace_xen_map_cache(phys_addr);
212
213 if (address_index == mapcache->last_address_index && !lock && !__size) {
214 trace_xen_map_cache_return(mapcache->last_address_vaddr + address_offset);
215 return mapcache->last_address_vaddr + address_offset;
216 }
217
218 /* size is always a multiple of MCACHE_BUCKET_SIZE */
219 if (size) {
220 __size = size + address_offset;
221 if (__size % MCACHE_BUCKET_SIZE) {
222 __size += MCACHE_BUCKET_SIZE - (__size % MCACHE_BUCKET_SIZE);
223 }
224 } else {
225 __size = MCACHE_BUCKET_SIZE;
226 }
227
228 entry = &mapcache->entry[address_index % mapcache->nr_buckets];
229
230 while (entry && entry->lock && entry->vaddr_base &&
231 (entry->paddr_index != address_index || entry->size != __size ||
232 !test_bits(address_offset >> XC_PAGE_SHIFT, size >> XC_PAGE_SHIFT,
233 entry->valid_mapping))) {
234 pentry = entry;
235 entry = entry->next;
236 }
237 if (!entry) {
238 entry = g_malloc0(sizeof (MapCacheEntry));
239 pentry->next = entry;
240 xen_remap_bucket(entry, __size, address_index);
241 } else if (!entry->lock) {
242 if (!entry->vaddr_base || entry->paddr_index != address_index ||
243 entry->size != __size ||
244 !test_bits(address_offset >> XC_PAGE_SHIFT, size >> XC_PAGE_SHIFT,
245 entry->valid_mapping)) {
246 xen_remap_bucket(entry, __size, address_index);
247 }
248 }
249
250 if(!test_bits(address_offset >> XC_PAGE_SHIFT, size >> XC_PAGE_SHIFT,
251 entry->valid_mapping)) {
252 mapcache->last_address_index = -1;
253 if (!translated && mapcache->phys_offset_to_gaddr) {
254 phys_addr = mapcache->phys_offset_to_gaddr(phys_addr, size, mapcache->opaque);
255 translated = true;
256 goto tryagain;
257 }
258 trace_xen_map_cache_return(NULL);
259 return NULL;
260 }
261
262 mapcache->last_address_index = address_index;
263 mapcache->last_address_vaddr = entry->vaddr_base;
264 if (lock) {
265 MapCacheRev *reventry = g_malloc0(sizeof(MapCacheRev));
266 entry->lock++;
267 reventry->vaddr_req = mapcache->last_address_vaddr + address_offset;
268 reventry->paddr_index = mapcache->last_address_index;
269 reventry->size = entry->size;
270 QTAILQ_INSERT_HEAD(&mapcache->locked_entries, reventry, next);
271 }
272
273 trace_xen_map_cache_return(mapcache->last_address_vaddr + address_offset);
274 return mapcache->last_address_vaddr + address_offset;
275 }
276
277 ram_addr_t xen_ram_addr_from_mapcache(void *ptr)
278 {
279 MapCacheEntry *entry = NULL;
280 MapCacheRev *reventry;
281 target_phys_addr_t paddr_index;
282 target_phys_addr_t size;
283 int found = 0;
284
285 QTAILQ_FOREACH(reventry, &mapcache->locked_entries, next) {
286 if (reventry->vaddr_req == ptr) {
287 paddr_index = reventry->paddr_index;
288 size = reventry->size;
289 found = 1;
290 break;
291 }
292 }
293 if (!found) {
294 fprintf(stderr, "%s, could not find %p\n", __func__, ptr);
295 QTAILQ_FOREACH(reventry, &mapcache->locked_entries, next) {
296 DPRINTF(" "TARGET_FMT_plx" -> %p is present\n", reventry->paddr_index,
297 reventry->vaddr_req);
298 }
299 abort();
300 return 0;
301 }
302
303 entry = &mapcache->entry[paddr_index % mapcache->nr_buckets];
304 while (entry && (entry->paddr_index != paddr_index || entry->size != size)) {
305 entry = entry->next;
306 }
307 if (!entry) {
308 DPRINTF("Trying to find address %p that is not in the mapcache!\n", ptr);
309 return 0;
310 }
311 return (reventry->paddr_index << MCACHE_BUCKET_SHIFT) +
312 ((unsigned long) ptr - (unsigned long) entry->vaddr_base);
313 }
314
315 void xen_invalidate_map_cache_entry(uint8_t *buffer)
316 {
317 MapCacheEntry *entry = NULL, *pentry = NULL;
318 MapCacheRev *reventry;
319 target_phys_addr_t paddr_index;
320 target_phys_addr_t size;
321 int found = 0;
322
323 if (mapcache->last_address_vaddr == buffer) {
324 mapcache->last_address_index = -1;
325 }
326
327 QTAILQ_FOREACH(reventry, &mapcache->locked_entries, next) {
328 if (reventry->vaddr_req == buffer) {
329 paddr_index = reventry->paddr_index;
330 size = reventry->size;
331 found = 1;
332 break;
333 }
334 }
335 if (!found) {
336 DPRINTF("%s, could not find %p\n", __func__, buffer);
337 QTAILQ_FOREACH(reventry, &mapcache->locked_entries, next) {
338 DPRINTF(" "TARGET_FMT_plx" -> %p is present\n", reventry->paddr_index, reventry->vaddr_req);
339 }
340 return;
341 }
342 QTAILQ_REMOVE(&mapcache->locked_entries, reventry, next);
343 g_free(reventry);
344
345 entry = &mapcache->entry[paddr_index % mapcache->nr_buckets];
346 while (entry && (entry->paddr_index != paddr_index || entry->size != size)) {
347 pentry = entry;
348 entry = entry->next;
349 }
350 if (!entry) {
351 DPRINTF("Trying to unmap address %p that is not in the mapcache!\n", buffer);
352 return;
353 }
354 entry->lock--;
355 if (entry->lock > 0 || pentry == NULL) {
356 return;
357 }
358
359 pentry->next = entry->next;
360 if (munmap(entry->vaddr_base, entry->size) != 0) {
361 perror("unmap fails");
362 exit(-1);
363 }
364 g_free(entry->valid_mapping);
365 g_free(entry);
366 }
367
368 void xen_invalidate_map_cache(void)
369 {
370 unsigned long i;
371 MapCacheRev *reventry;
372
373 /* Flush pending AIO before destroying the mapcache */
374 bdrv_drain_all();
375
376 QTAILQ_FOREACH(reventry, &mapcache->locked_entries, next) {
377 DPRINTF("There should be no locked mappings at this time, "
378 "but "TARGET_FMT_plx" -> %p is present\n",
379 reventry->paddr_index, reventry->vaddr_req);
380 }
381
382 mapcache_lock();
383
384 for (i = 0; i < mapcache->nr_buckets; i++) {
385 MapCacheEntry *entry = &mapcache->entry[i];
386
387 if (entry->vaddr_base == NULL) {
388 continue;
389 }
390 if (entry->lock > 0) {
391 continue;
392 }
393
394 if (munmap(entry->vaddr_base, entry->size) != 0) {
395 perror("unmap fails");
396 exit(-1);
397 }
398
399 entry->paddr_index = 0;
400 entry->vaddr_base = NULL;
401 entry->size = 0;
402 g_free(entry->valid_mapping);
403 entry->valid_mapping = NULL;
404 }
405
406 mapcache->last_address_index = -1;
407 mapcache->last_address_vaddr = NULL;
408
409 mapcache_unlock();
410 }