hw/net: fix mcf_fec driver receiver
[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/xen_backend.h"
16 #include "sysemu/blockdev.h"
17 #include "qemu/bitmap.h"
18
19 #include <xen/hvm/params.h>
20 #include <sys/mman.h>
21
22 #include "sysemu/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 HOST_LONG_BITS == 32
37 # define MCACHE_BUCKET_SHIFT 16
38 # define MCACHE_MAX_SIZE (1UL<<31) /* 2GB Cap */
39 #else
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 typedef struct MapCacheEntry {
53 hwaddr paddr_index;
54 uint8_t *vaddr_base;
55 unsigned long *valid_mapping;
56 uint8_t lock;
57 hwaddr size;
58 struct MapCacheEntry *next;
59 } MapCacheEntry;
60
61 typedef struct MapCacheRev {
62 uint8_t *vaddr_req;
63 hwaddr paddr_index;
64 hwaddr size;
65 QTAILQ_ENTRY(MapCacheRev) next;
66 } MapCacheRev;
67
68 typedef struct MapCache {
69 MapCacheEntry *entry;
70 unsigned long nr_buckets;
71 QTAILQ_HEAD(map_cache_head, MapCacheRev) locked_entries;
72
73 /* For most cases (>99.9%), the page address is the same. */
74 MapCacheEntry *last_entry;
75 unsigned long max_mcache_size;
76 unsigned int mcache_bucket_shift;
77
78 phys_offset_to_gaddr_t phys_offset_to_gaddr;
79 QemuMutex lock;
80 void *opaque;
81 } MapCache;
82
83 static MapCache *mapcache;
84
85 static inline void mapcache_lock(void)
86 {
87 qemu_mutex_lock(&mapcache->lock);
88 }
89
90 static inline void mapcache_unlock(void)
91 {
92 qemu_mutex_unlock(&mapcache->lock);
93 }
94
95 static inline int test_bits(int nr, int size, const unsigned long *addr)
96 {
97 unsigned long res = find_next_zero_bit(addr, size + nr, nr);
98 if (res >= nr + size)
99 return 1;
100 else
101 return 0;
102 }
103
104 void xen_map_cache_init(phys_offset_to_gaddr_t f, void *opaque)
105 {
106 unsigned long size;
107 struct rlimit rlimit_as;
108
109 mapcache = g_malloc0(sizeof (MapCache));
110
111 mapcache->phys_offset_to_gaddr = f;
112 mapcache->opaque = opaque;
113 qemu_mutex_init(&mapcache->lock);
114
115 QTAILQ_INIT(&mapcache->locked_entries);
116
117 if (geteuid() == 0) {
118 rlimit_as.rlim_cur = RLIM_INFINITY;
119 rlimit_as.rlim_max = RLIM_INFINITY;
120 mapcache->max_mcache_size = MCACHE_MAX_SIZE;
121 } else {
122 getrlimit(RLIMIT_AS, &rlimit_as);
123 rlimit_as.rlim_cur = rlimit_as.rlim_max;
124
125 if (rlimit_as.rlim_max != RLIM_INFINITY) {
126 fprintf(stderr, "Warning: QEMU's maximum size of virtual"
127 " memory is not infinity.\n");
128 }
129 if (rlimit_as.rlim_max < MCACHE_MAX_SIZE + NON_MCACHE_MEMORY_SIZE) {
130 mapcache->max_mcache_size = rlimit_as.rlim_max -
131 NON_MCACHE_MEMORY_SIZE;
132 } else {
133 mapcache->max_mcache_size = MCACHE_MAX_SIZE;
134 }
135 }
136
137 setrlimit(RLIMIT_AS, &rlimit_as);
138
139 mapcache->nr_buckets =
140 (((mapcache->max_mcache_size >> XC_PAGE_SHIFT) +
141 (1UL << (MCACHE_BUCKET_SHIFT - XC_PAGE_SHIFT)) - 1) >>
142 (MCACHE_BUCKET_SHIFT - XC_PAGE_SHIFT));
143
144 size = mapcache->nr_buckets * sizeof (MapCacheEntry);
145 size = (size + XC_PAGE_SIZE - 1) & ~(XC_PAGE_SIZE - 1);
146 DPRINTF("%s, nr_buckets = %lx size %lu\n", __func__,
147 mapcache->nr_buckets, size);
148 mapcache->entry = g_malloc0(size);
149 }
150
151 static void xen_remap_bucket(MapCacheEntry *entry,
152 hwaddr size,
153 hwaddr address_index)
154 {
155 uint8_t *vaddr_base;
156 xen_pfn_t *pfns;
157 int *err;
158 unsigned int i;
159 hwaddr nb_pfn = size >> XC_PAGE_SHIFT;
160
161 trace_xen_remap_bucket(address_index);
162
163 pfns = g_malloc0(nb_pfn * sizeof (xen_pfn_t));
164 err = g_malloc0(nb_pfn * sizeof (int));
165
166 if (entry->vaddr_base != NULL) {
167 if (munmap(entry->vaddr_base, entry->size) != 0) {
168 perror("unmap fails");
169 exit(-1);
170 }
171 }
172 if (entry->valid_mapping != NULL) {
173 g_free(entry->valid_mapping);
174 entry->valid_mapping = NULL;
175 }
176
177 for (i = 0; i < nb_pfn; i++) {
178 pfns[i] = (address_index << (MCACHE_BUCKET_SHIFT-XC_PAGE_SHIFT)) + i;
179 }
180
181 vaddr_base = xc_map_foreign_bulk(xen_xc, xen_domid, PROT_READ|PROT_WRITE,
182 pfns, err, nb_pfn);
183 if (vaddr_base == NULL) {
184 perror("xc_map_foreign_bulk");
185 exit(-1);
186 }
187
188 entry->vaddr_base = vaddr_base;
189 entry->paddr_index = address_index;
190 entry->size = size;
191 entry->valid_mapping = (unsigned long *) g_malloc0(sizeof(unsigned long) *
192 BITS_TO_LONGS(size >> XC_PAGE_SHIFT));
193
194 bitmap_zero(entry->valid_mapping, nb_pfn);
195 for (i = 0; i < nb_pfn; i++) {
196 if (!err[i]) {
197 bitmap_set(entry->valid_mapping, i, 1);
198 }
199 }
200
201 g_free(pfns);
202 g_free(err);
203 }
204
205 static uint8_t *xen_map_cache_unlocked(hwaddr phys_addr, hwaddr size,
206 uint8_t lock)
207 {
208 MapCacheEntry *entry, *pentry = NULL;
209 hwaddr address_index;
210 hwaddr address_offset;
211 hwaddr cache_size = size;
212 hwaddr test_bit_size;
213 bool translated = false;
214
215 tryagain:
216 address_index = phys_addr >> MCACHE_BUCKET_SHIFT;
217 address_offset = phys_addr & (MCACHE_BUCKET_SIZE - 1);
218
219 trace_xen_map_cache(phys_addr);
220
221 /* test_bit_size is always a multiple of XC_PAGE_SIZE */
222 if (size) {
223 test_bit_size = size + (phys_addr & (XC_PAGE_SIZE - 1));
224
225 if (test_bit_size % XC_PAGE_SIZE) {
226 test_bit_size += XC_PAGE_SIZE - (test_bit_size % XC_PAGE_SIZE);
227 }
228 } else {
229 test_bit_size = XC_PAGE_SIZE;
230 }
231
232 if (mapcache->last_entry != NULL &&
233 mapcache->last_entry->paddr_index == address_index &&
234 !lock && !size &&
235 test_bits(address_offset >> XC_PAGE_SHIFT,
236 test_bit_size >> XC_PAGE_SHIFT,
237 mapcache->last_entry->valid_mapping)) {
238 trace_xen_map_cache_return(mapcache->last_entry->vaddr_base + address_offset);
239 return mapcache->last_entry->vaddr_base + address_offset;
240 }
241
242 /* size is always a multiple of MCACHE_BUCKET_SIZE */
243 if (size) {
244 cache_size = size + address_offset;
245 if (cache_size % MCACHE_BUCKET_SIZE) {
246 cache_size += MCACHE_BUCKET_SIZE - (cache_size % MCACHE_BUCKET_SIZE);
247 }
248 } else {
249 cache_size = MCACHE_BUCKET_SIZE;
250 }
251
252 entry = &mapcache->entry[address_index % mapcache->nr_buckets];
253
254 while (entry && entry->lock && entry->vaddr_base &&
255 (entry->paddr_index != address_index || entry->size != cache_size ||
256 !test_bits(address_offset >> XC_PAGE_SHIFT,
257 test_bit_size >> XC_PAGE_SHIFT,
258 entry->valid_mapping))) {
259 pentry = entry;
260 entry = entry->next;
261 }
262 if (!entry) {
263 entry = g_malloc0(sizeof (MapCacheEntry));
264 pentry->next = entry;
265 xen_remap_bucket(entry, cache_size, address_index);
266 } else if (!entry->lock) {
267 if (!entry->vaddr_base || entry->paddr_index != address_index ||
268 entry->size != cache_size ||
269 !test_bits(address_offset >> XC_PAGE_SHIFT,
270 test_bit_size >> XC_PAGE_SHIFT,
271 entry->valid_mapping)) {
272 xen_remap_bucket(entry, cache_size, address_index);
273 }
274 }
275
276 if(!test_bits(address_offset >> XC_PAGE_SHIFT,
277 test_bit_size >> XC_PAGE_SHIFT,
278 entry->valid_mapping)) {
279 mapcache->last_entry = NULL;
280 if (!translated && mapcache->phys_offset_to_gaddr) {
281 phys_addr = mapcache->phys_offset_to_gaddr(phys_addr, size, mapcache->opaque);
282 translated = true;
283 goto tryagain;
284 }
285 trace_xen_map_cache_return(NULL);
286 return NULL;
287 }
288
289 mapcache->last_entry = entry;
290 if (lock) {
291 MapCacheRev *reventry = g_malloc0(sizeof(MapCacheRev));
292 entry->lock++;
293 reventry->vaddr_req = mapcache->last_entry->vaddr_base + address_offset;
294 reventry->paddr_index = mapcache->last_entry->paddr_index;
295 reventry->size = entry->size;
296 QTAILQ_INSERT_HEAD(&mapcache->locked_entries, reventry, next);
297 }
298
299 trace_xen_map_cache_return(mapcache->last_entry->vaddr_base + address_offset);
300 return mapcache->last_entry->vaddr_base + address_offset;
301 }
302
303 uint8_t *xen_map_cache(hwaddr phys_addr, hwaddr size,
304 uint8_t lock)
305 {
306 uint8_t *p;
307
308 mapcache_lock();
309 p = xen_map_cache_unlocked(phys_addr, size, lock);
310 mapcache_unlock();
311 return p;
312 }
313
314 ram_addr_t xen_ram_addr_from_mapcache(void *ptr)
315 {
316 MapCacheEntry *entry = NULL;
317 MapCacheRev *reventry;
318 hwaddr paddr_index;
319 hwaddr size;
320 ram_addr_t raddr;
321 int found = 0;
322
323 mapcache_lock();
324 QTAILQ_FOREACH(reventry, &mapcache->locked_entries, next) {
325 if (reventry->vaddr_req == ptr) {
326 paddr_index = reventry->paddr_index;
327 size = reventry->size;
328 found = 1;
329 break;
330 }
331 }
332 if (!found) {
333 fprintf(stderr, "%s, could not find %p\n", __func__, ptr);
334 QTAILQ_FOREACH(reventry, &mapcache->locked_entries, next) {
335 DPRINTF(" "TARGET_FMT_plx" -> %p is present\n", reventry->paddr_index,
336 reventry->vaddr_req);
337 }
338 abort();
339 return 0;
340 }
341
342 entry = &mapcache->entry[paddr_index % mapcache->nr_buckets];
343 while (entry && (entry->paddr_index != paddr_index || entry->size != size)) {
344 entry = entry->next;
345 }
346 if (!entry) {
347 DPRINTF("Trying to find address %p that is not in the mapcache!\n", ptr);
348 raddr = 0;
349 } else {
350 raddr = (reventry->paddr_index << MCACHE_BUCKET_SHIFT) +
351 ((unsigned long) ptr - (unsigned long) entry->vaddr_base);
352 }
353 mapcache_unlock();
354 return raddr;
355 }
356
357 static void xen_invalidate_map_cache_entry_unlocked(uint8_t *buffer)
358 {
359 MapCacheEntry *entry = NULL, *pentry = NULL;
360 MapCacheRev *reventry;
361 hwaddr paddr_index;
362 hwaddr size;
363 int found = 0;
364
365 QTAILQ_FOREACH(reventry, &mapcache->locked_entries, next) {
366 if (reventry->vaddr_req == buffer) {
367 paddr_index = reventry->paddr_index;
368 size = reventry->size;
369 found = 1;
370 break;
371 }
372 }
373 if (!found) {
374 DPRINTF("%s, could not find %p\n", __func__, buffer);
375 QTAILQ_FOREACH(reventry, &mapcache->locked_entries, next) {
376 DPRINTF(" "TARGET_FMT_plx" -> %p is present\n", reventry->paddr_index, reventry->vaddr_req);
377 }
378 return;
379 }
380 QTAILQ_REMOVE(&mapcache->locked_entries, reventry, next);
381 g_free(reventry);
382
383 if (mapcache->last_entry != NULL &&
384 mapcache->last_entry->paddr_index == paddr_index) {
385 mapcache->last_entry = NULL;
386 }
387
388 entry = &mapcache->entry[paddr_index % mapcache->nr_buckets];
389 while (entry && (entry->paddr_index != paddr_index || entry->size != size)) {
390 pentry = entry;
391 entry = entry->next;
392 }
393 if (!entry) {
394 DPRINTF("Trying to unmap address %p that is not in the mapcache!\n", buffer);
395 return;
396 }
397 entry->lock--;
398 if (entry->lock > 0 || pentry == NULL) {
399 return;
400 }
401
402 pentry->next = entry->next;
403 if (munmap(entry->vaddr_base, entry->size) != 0) {
404 perror("unmap fails");
405 exit(-1);
406 }
407 g_free(entry->valid_mapping);
408 g_free(entry);
409 }
410
411 void xen_invalidate_map_cache_entry(uint8_t *buffer)
412 {
413 mapcache_lock();
414 xen_invalidate_map_cache_entry_unlocked(buffer);
415 mapcache_unlock();
416 }
417
418 void xen_invalidate_map_cache(void)
419 {
420 unsigned long i;
421 MapCacheRev *reventry;
422
423 /* Flush pending AIO before destroying the mapcache */
424 bdrv_drain_all();
425
426 mapcache_lock();
427
428 QTAILQ_FOREACH(reventry, &mapcache->locked_entries, next) {
429 DPRINTF("There should be no locked mappings at this time, "
430 "but "TARGET_FMT_plx" -> %p is present\n",
431 reventry->paddr_index, reventry->vaddr_req);
432 }
433
434 for (i = 0; i < mapcache->nr_buckets; i++) {
435 MapCacheEntry *entry = &mapcache->entry[i];
436
437 if (entry->vaddr_base == NULL) {
438 continue;
439 }
440 if (entry->lock > 0) {
441 continue;
442 }
443
444 if (munmap(entry->vaddr_base, entry->size) != 0) {
445 perror("unmap fails");
446 exit(-1);
447 }
448
449 entry->paddr_index = 0;
450 entry->vaddr_base = NULL;
451 entry->size = 0;
452 g_free(entry->valid_mapping);
453 entry->valid_mapping = NULL;
454 }
455
456 mapcache->last_entry = NULL;
457
458 mapcache_unlock();
459 }