ppc/pnv: Add support for POWER8+ LPC Controller
[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 "qemu/osdep.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
21 #include "sysemu/xen-mapcache.h"
22 #include "trace-root.h"
23
24
25 //#define MAPCACHE_DEBUG
26
27 #ifdef MAPCACHE_DEBUG
28 # define DPRINTF(fmt, ...) do { \
29 fprintf(stderr, "xen_mapcache: " fmt, ## __VA_ARGS__); \
30 } while (0)
31 #else
32 # define DPRINTF(fmt, ...) do { } while (0)
33 #endif
34
35 #if HOST_LONG_BITS == 32
36 # define MCACHE_BUCKET_SHIFT 16
37 # define MCACHE_MAX_SIZE (1UL<<31) /* 2GB Cap */
38 #else
39 # define MCACHE_BUCKET_SHIFT 20
40 # define MCACHE_MAX_SIZE (1UL<<35) /* 32GB Cap */
41 #endif
42 #define MCACHE_BUCKET_SIZE (1UL << MCACHE_BUCKET_SHIFT)
43
44 /* This is the size of the virtual address space reserve to QEMU that will not
45 * be use by MapCache.
46 * From empirical tests I observed that qemu use 75MB more than the
47 * max_mcache_size.
48 */
49 #define NON_MCACHE_MEMORY_SIZE (80 * 1024 * 1024)
50
51 typedef struct MapCacheEntry {
52 hwaddr paddr_index;
53 uint8_t *vaddr_base;
54 unsigned long *valid_mapping;
55 uint8_t lock;
56 hwaddr size;
57 struct MapCacheEntry *next;
58 } MapCacheEntry;
59
60 typedef struct MapCacheRev {
61 uint8_t *vaddr_req;
62 hwaddr paddr_index;
63 hwaddr size;
64 QTAILQ_ENTRY(MapCacheRev) next;
65 } MapCacheRev;
66
67 typedef struct MapCache {
68 MapCacheEntry *entry;
69 unsigned long nr_buckets;
70 QTAILQ_HEAD(map_cache_head, MapCacheRev) locked_entries;
71
72 /* For most cases (>99.9%), the page address is the same. */
73 MapCacheEntry *last_entry;
74 unsigned long max_mcache_size;
75 unsigned int mcache_bucket_shift;
76
77 phys_offset_to_gaddr_t phys_offset_to_gaddr;
78 QemuMutex lock;
79 void *opaque;
80 } MapCache;
81
82 static MapCache *mapcache;
83
84 static inline void mapcache_lock(void)
85 {
86 qemu_mutex_lock(&mapcache->lock);
87 }
88
89 static inline void mapcache_unlock(void)
90 {
91 qemu_mutex_unlock(&mapcache->lock);
92 }
93
94 static inline int test_bits(int nr, int size, const unsigned long *addr)
95 {
96 unsigned long res = find_next_zero_bit(addr, size + nr, nr);
97 if (res >= nr + size)
98 return 1;
99 else
100 return 0;
101 }
102
103 void xen_map_cache_init(phys_offset_to_gaddr_t f, void *opaque)
104 {
105 unsigned long size;
106 struct rlimit rlimit_as;
107
108 mapcache = g_malloc0(sizeof (MapCache));
109
110 mapcache->phys_offset_to_gaddr = f;
111 mapcache->opaque = opaque;
112 qemu_mutex_init(&mapcache->lock);
113
114 QTAILQ_INIT(&mapcache->locked_entries);
115
116 if (geteuid() == 0) {
117 rlimit_as.rlim_cur = RLIM_INFINITY;
118 rlimit_as.rlim_max = RLIM_INFINITY;
119 mapcache->max_mcache_size = MCACHE_MAX_SIZE;
120 } else {
121 getrlimit(RLIMIT_AS, &rlimit_as);
122 rlimit_as.rlim_cur = rlimit_as.rlim_max;
123
124 if (rlimit_as.rlim_max != RLIM_INFINITY) {
125 fprintf(stderr, "Warning: QEMU's maximum size of virtual"
126 " memory is not infinity.\n");
127 }
128 if (rlimit_as.rlim_max < MCACHE_MAX_SIZE + NON_MCACHE_MEMORY_SIZE) {
129 mapcache->max_mcache_size = rlimit_as.rlim_max -
130 NON_MCACHE_MEMORY_SIZE;
131 } else {
132 mapcache->max_mcache_size = MCACHE_MAX_SIZE;
133 }
134 }
135
136 setrlimit(RLIMIT_AS, &rlimit_as);
137
138 mapcache->nr_buckets =
139 (((mapcache->max_mcache_size >> XC_PAGE_SHIFT) +
140 (1UL << (MCACHE_BUCKET_SHIFT - XC_PAGE_SHIFT)) - 1) >>
141 (MCACHE_BUCKET_SHIFT - XC_PAGE_SHIFT));
142
143 size = mapcache->nr_buckets * sizeof (MapCacheEntry);
144 size = (size + XC_PAGE_SIZE - 1) & ~(XC_PAGE_SIZE - 1);
145 DPRINTF("%s, nr_buckets = %lx size %lu\n", __func__,
146 mapcache->nr_buckets, size);
147 mapcache->entry = g_malloc0(size);
148 }
149
150 static void xen_remap_bucket(MapCacheEntry *entry,
151 hwaddr size,
152 hwaddr address_index)
153 {
154 uint8_t *vaddr_base;
155 xen_pfn_t *pfns;
156 int *err;
157 unsigned int i;
158 hwaddr nb_pfn = size >> XC_PAGE_SHIFT;
159
160 trace_xen_remap_bucket(address_index);
161
162 pfns = g_malloc0(nb_pfn * sizeof (xen_pfn_t));
163 err = g_malloc0(nb_pfn * sizeof (int));
164
165 if (entry->vaddr_base != NULL) {
166 ram_block_notify_remove(entry->vaddr_base, entry->size);
167 if (munmap(entry->vaddr_base, entry->size) != 0) {
168 perror("unmap fails");
169 exit(-1);
170 }
171 }
172 g_free(entry->valid_mapping);
173 entry->valid_mapping = NULL;
174
175 for (i = 0; i < nb_pfn; i++) {
176 pfns[i] = (address_index << (MCACHE_BUCKET_SHIFT-XC_PAGE_SHIFT)) + i;
177 }
178
179 vaddr_base = xenforeignmemory_map(xen_fmem, xen_domid, PROT_READ|PROT_WRITE,
180 nb_pfn, pfns, err);
181 if (vaddr_base == NULL) {
182 perror("xenforeignmemory_map");
183 exit(-1);
184 }
185
186 entry->vaddr_base = vaddr_base;
187 entry->paddr_index = address_index;
188 entry->size = size;
189 entry->valid_mapping = (unsigned long *) g_malloc0(sizeof(unsigned long) *
190 BITS_TO_LONGS(size >> XC_PAGE_SHIFT));
191
192 ram_block_notify_add(entry->vaddr_base, entry->size);
193 bitmap_zero(entry->valid_mapping, nb_pfn);
194 for (i = 0; i < nb_pfn; i++) {
195 if (!err[i]) {
196 bitmap_set(entry->valid_mapping, i, 1);
197 }
198 }
199
200 g_free(pfns);
201 g_free(err);
202 }
203
204 static uint8_t *xen_map_cache_unlocked(hwaddr phys_addr, hwaddr size,
205 uint8_t lock)
206 {
207 MapCacheEntry *entry, *pentry = NULL;
208 hwaddr address_index;
209 hwaddr address_offset;
210 hwaddr cache_size = size;
211 hwaddr test_bit_size;
212 bool translated = false;
213
214 tryagain:
215 address_index = phys_addr >> MCACHE_BUCKET_SHIFT;
216 address_offset = phys_addr & (MCACHE_BUCKET_SIZE - 1);
217
218 trace_xen_map_cache(phys_addr);
219
220 /* test_bit_size is always a multiple of XC_PAGE_SIZE */
221 if (size) {
222 test_bit_size = size + (phys_addr & (XC_PAGE_SIZE - 1));
223
224 if (test_bit_size % XC_PAGE_SIZE) {
225 test_bit_size += XC_PAGE_SIZE - (test_bit_size % XC_PAGE_SIZE);
226 }
227 } else {
228 test_bit_size = XC_PAGE_SIZE;
229 }
230
231 if (mapcache->last_entry != NULL &&
232 mapcache->last_entry->paddr_index == address_index &&
233 !lock && !size &&
234 test_bits(address_offset >> XC_PAGE_SHIFT,
235 test_bit_size >> XC_PAGE_SHIFT,
236 mapcache->last_entry->valid_mapping)) {
237 trace_xen_map_cache_return(mapcache->last_entry->vaddr_base + address_offset);
238 return mapcache->last_entry->vaddr_base + address_offset;
239 }
240
241 /* size is always a multiple of MCACHE_BUCKET_SIZE */
242 if (size) {
243 cache_size = size + address_offset;
244 if (cache_size % MCACHE_BUCKET_SIZE) {
245 cache_size += MCACHE_BUCKET_SIZE - (cache_size % MCACHE_BUCKET_SIZE);
246 }
247 } else {
248 cache_size = MCACHE_BUCKET_SIZE;
249 }
250
251 entry = &mapcache->entry[address_index % mapcache->nr_buckets];
252
253 while (entry && entry->lock && entry->vaddr_base &&
254 (entry->paddr_index != address_index || entry->size != cache_size ||
255 !test_bits(address_offset >> XC_PAGE_SHIFT,
256 test_bit_size >> XC_PAGE_SHIFT,
257 entry->valid_mapping))) {
258 pentry = entry;
259 entry = entry->next;
260 }
261 if (!entry) {
262 entry = g_malloc0(sizeof (MapCacheEntry));
263 pentry->next = entry;
264 xen_remap_bucket(entry, cache_size, address_index);
265 } else if (!entry->lock) {
266 if (!entry->vaddr_base || entry->paddr_index != address_index ||
267 entry->size != cache_size ||
268 !test_bits(address_offset >> XC_PAGE_SHIFT,
269 test_bit_size >> XC_PAGE_SHIFT,
270 entry->valid_mapping)) {
271 xen_remap_bucket(entry, cache_size, address_index);
272 }
273 }
274
275 if(!test_bits(address_offset >> XC_PAGE_SHIFT,
276 test_bit_size >> XC_PAGE_SHIFT,
277 entry->valid_mapping)) {
278 mapcache->last_entry = NULL;
279 if (!translated && mapcache->phys_offset_to_gaddr) {
280 phys_addr = mapcache->phys_offset_to_gaddr(phys_addr, size, mapcache->opaque);
281 translated = true;
282 goto tryagain;
283 }
284 trace_xen_map_cache_return(NULL);
285 return NULL;
286 }
287
288 mapcache->last_entry = entry;
289 if (lock) {
290 MapCacheRev *reventry = g_malloc0(sizeof(MapCacheRev));
291 entry->lock++;
292 reventry->vaddr_req = mapcache->last_entry->vaddr_base + address_offset;
293 reventry->paddr_index = mapcache->last_entry->paddr_index;
294 reventry->size = entry->size;
295 QTAILQ_INSERT_HEAD(&mapcache->locked_entries, reventry, next);
296 }
297
298 trace_xen_map_cache_return(mapcache->last_entry->vaddr_base + address_offset);
299 return mapcache->last_entry->vaddr_base + address_offset;
300 }
301
302 uint8_t *xen_map_cache(hwaddr phys_addr, hwaddr size,
303 uint8_t lock)
304 {
305 uint8_t *p;
306
307 mapcache_lock();
308 p = xen_map_cache_unlocked(phys_addr, size, lock);
309 mapcache_unlock();
310 return p;
311 }
312
313 ram_addr_t xen_ram_addr_from_mapcache(void *ptr)
314 {
315 MapCacheEntry *entry = NULL;
316 MapCacheRev *reventry;
317 hwaddr paddr_index;
318 hwaddr size;
319 ram_addr_t raddr;
320 int found = 0;
321
322 mapcache_lock();
323 QTAILQ_FOREACH(reventry, &mapcache->locked_entries, next) {
324 if (reventry->vaddr_req == ptr) {
325 paddr_index = reventry->paddr_index;
326 size = reventry->size;
327 found = 1;
328 break;
329 }
330 }
331 if (!found) {
332 fprintf(stderr, "%s, could not find %p\n", __func__, ptr);
333 QTAILQ_FOREACH(reventry, &mapcache->locked_entries, next) {
334 DPRINTF(" "TARGET_FMT_plx" -> %p is present\n", reventry->paddr_index,
335 reventry->vaddr_req);
336 }
337 abort();
338 return 0;
339 }
340
341 entry = &mapcache->entry[paddr_index % mapcache->nr_buckets];
342 while (entry && (entry->paddr_index != paddr_index || entry->size != size)) {
343 entry = entry->next;
344 }
345 if (!entry) {
346 DPRINTF("Trying to find address %p that is not in the mapcache!\n", ptr);
347 raddr = 0;
348 } else {
349 raddr = (reventry->paddr_index << MCACHE_BUCKET_SHIFT) +
350 ((unsigned long) ptr - (unsigned long) entry->vaddr_base);
351 }
352 mapcache_unlock();
353 return raddr;
354 }
355
356 static void xen_invalidate_map_cache_entry_unlocked(uint8_t *buffer)
357 {
358 MapCacheEntry *entry = NULL, *pentry = NULL;
359 MapCacheRev *reventry;
360 hwaddr paddr_index;
361 hwaddr size;
362 int found = 0;
363
364 QTAILQ_FOREACH(reventry, &mapcache->locked_entries, next) {
365 if (reventry->vaddr_req == buffer) {
366 paddr_index = reventry->paddr_index;
367 size = reventry->size;
368 found = 1;
369 break;
370 }
371 }
372 if (!found) {
373 DPRINTF("%s, could not find %p\n", __func__, buffer);
374 QTAILQ_FOREACH(reventry, &mapcache->locked_entries, next) {
375 DPRINTF(" "TARGET_FMT_plx" -> %p is present\n", reventry->paddr_index, reventry->vaddr_req);
376 }
377 return;
378 }
379 QTAILQ_REMOVE(&mapcache->locked_entries, reventry, next);
380 g_free(reventry);
381
382 if (mapcache->last_entry != NULL &&
383 mapcache->last_entry->paddr_index == paddr_index) {
384 mapcache->last_entry = NULL;
385 }
386
387 entry = &mapcache->entry[paddr_index % mapcache->nr_buckets];
388 while (entry && (entry->paddr_index != paddr_index || entry->size != size)) {
389 pentry = entry;
390 entry = entry->next;
391 }
392 if (!entry) {
393 DPRINTF("Trying to unmap address %p that is not in the mapcache!\n", buffer);
394 return;
395 }
396 entry->lock--;
397 if (entry->lock > 0 || pentry == NULL) {
398 return;
399 }
400
401 pentry->next = entry->next;
402 ram_block_notify_remove(entry->vaddr_base, entry->size);
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 }