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-rw-r--r--fs/mbcache.c168
1 files changed, 50 insertions, 118 deletions
diff --git a/fs/mbcache.c b/fs/mbcache.c
index e28f21b95344..cf4e6cdfd15b 100644
--- a/fs/mbcache.c
+++ b/fs/mbcache.c
@@ -79,15 +79,11 @@ EXPORT_SYMBOL(mb_cache_entry_find_next);
79struct mb_cache { 79struct mb_cache {
80 struct list_head c_cache_list; 80 struct list_head c_cache_list;
81 const char *c_name; 81 const char *c_name;
82 struct mb_cache_op c_op;
83 atomic_t c_entry_count; 82 atomic_t c_entry_count;
84 int c_bucket_bits; 83 int c_bucket_bits;
85#ifndef MB_CACHE_INDEXES_COUNT 84 struct kmem_cache *c_entry_cache;
86 int c_indexes_count;
87#endif
88 struct kmem_cache *c_entry_cache;
89 struct list_head *c_block_hash; 85 struct list_head *c_block_hash;
90 struct list_head *c_indexes_hash[0]; 86 struct list_head *c_index_hash;
91}; 87};
92 88
93 89
@@ -101,16 +97,6 @@ static LIST_HEAD(mb_cache_list);
101static LIST_HEAD(mb_cache_lru_list); 97static LIST_HEAD(mb_cache_lru_list);
102static DEFINE_SPINLOCK(mb_cache_spinlock); 98static DEFINE_SPINLOCK(mb_cache_spinlock);
103 99
104static inline int
105mb_cache_indexes(struct mb_cache *cache)
106{
107#ifdef MB_CACHE_INDEXES_COUNT
108 return MB_CACHE_INDEXES_COUNT;
109#else
110 return cache->c_indexes_count;
111#endif
112}
113
114/* 100/*
115 * What the mbcache registers as to get shrunk dynamically. 101 * What the mbcache registers as to get shrunk dynamically.
116 */ 102 */
@@ -132,12 +118,9 @@ __mb_cache_entry_is_hashed(struct mb_cache_entry *ce)
132static void 118static void
133__mb_cache_entry_unhash(struct mb_cache_entry *ce) 119__mb_cache_entry_unhash(struct mb_cache_entry *ce)
134{ 120{
135 int n;
136
137 if (__mb_cache_entry_is_hashed(ce)) { 121 if (__mb_cache_entry_is_hashed(ce)) {
138 list_del_init(&ce->e_block_list); 122 list_del_init(&ce->e_block_list);
139 for (n=0; n<mb_cache_indexes(ce->e_cache); n++) 123 list_del(&ce->e_index.o_list);
140 list_del(&ce->e_indexes[n].o_list);
141 } 124 }
142} 125}
143 126
@@ -148,16 +131,8 @@ __mb_cache_entry_forget(struct mb_cache_entry *ce, gfp_t gfp_mask)
148 struct mb_cache *cache = ce->e_cache; 131 struct mb_cache *cache = ce->e_cache;
149 132
150 mb_assert(!(ce->e_used || ce->e_queued)); 133 mb_assert(!(ce->e_used || ce->e_queued));
151 if (cache->c_op.free && cache->c_op.free(ce, gfp_mask)) { 134 kmem_cache_free(cache->c_entry_cache, ce);
152 /* free failed -- put back on the lru list 135 atomic_dec(&cache->c_entry_count);
153 for freeing later. */
154 spin_lock(&mb_cache_spinlock);
155 list_add(&ce->e_lru_list, &mb_cache_lru_list);
156 spin_unlock(&mb_cache_spinlock);
157 } else {
158 kmem_cache_free(cache->c_entry_cache, ce);
159 atomic_dec(&cache->c_entry_count);
160 }
161} 136}
162 137
163 138
@@ -201,22 +176,12 @@ static int
201mb_cache_shrink_fn(struct shrinker *shrink, int nr_to_scan, gfp_t gfp_mask) 176mb_cache_shrink_fn(struct shrinker *shrink, int nr_to_scan, gfp_t gfp_mask)
202{ 177{
203 LIST_HEAD(free_list); 178 LIST_HEAD(free_list);
204 struct list_head *l, *ltmp; 179 struct mb_cache *cache;
180 struct mb_cache_entry *entry, *tmp;
205 int count = 0; 181 int count = 0;
206 182
207 spin_lock(&mb_cache_spinlock);
208 list_for_each(l, &mb_cache_list) {
209 struct mb_cache *cache =
210 list_entry(l, struct mb_cache, c_cache_list);
211 mb_debug("cache %s (%d)", cache->c_name,
212 atomic_read(&cache->c_entry_count));
213 count += atomic_read(&cache->c_entry_count);
214 }
215 mb_debug("trying to free %d entries", nr_to_scan); 183 mb_debug("trying to free %d entries", nr_to_scan);
216 if (nr_to_scan == 0) { 184 spin_lock(&mb_cache_spinlock);
217 spin_unlock(&mb_cache_spinlock);
218 goto out;
219 }
220 while (nr_to_scan-- && !list_empty(&mb_cache_lru_list)) { 185 while (nr_to_scan-- && !list_empty(&mb_cache_lru_list)) {
221 struct mb_cache_entry *ce = 186 struct mb_cache_entry *ce =
222 list_entry(mb_cache_lru_list.next, 187 list_entry(mb_cache_lru_list.next,
@@ -224,12 +189,15 @@ mb_cache_shrink_fn(struct shrinker *shrink, int nr_to_scan, gfp_t gfp_mask)
224 list_move_tail(&ce->e_lru_list, &free_list); 189 list_move_tail(&ce->e_lru_list, &free_list);
225 __mb_cache_entry_unhash(ce); 190 __mb_cache_entry_unhash(ce);
226 } 191 }
192 list_for_each_entry(cache, &mb_cache_list, c_cache_list) {
193 mb_debug("cache %s (%d)", cache->c_name,
194 atomic_read(&cache->c_entry_count));
195 count += atomic_read(&cache->c_entry_count);
196 }
227 spin_unlock(&mb_cache_spinlock); 197 spin_unlock(&mb_cache_spinlock);
228 list_for_each_safe(l, ltmp, &free_list) { 198 list_for_each_entry_safe(entry, tmp, &free_list, e_lru_list) {
229 __mb_cache_entry_forget(list_entry(l, struct mb_cache_entry, 199 __mb_cache_entry_forget(entry, gfp_mask);
230 e_lru_list), gfp_mask);
231 } 200 }
232out:
233 return (count / 100) * sysctl_vfs_cache_pressure; 201 return (count / 100) * sysctl_vfs_cache_pressure;
234} 202}
235 203
@@ -243,72 +211,49 @@ out:
243 * memory was available. 211 * memory was available.
244 * 212 *
245 * @name: name of the cache (informal) 213 * @name: name of the cache (informal)
246 * @cache_op: contains the callback called when freeing a cache entry
247 * @entry_size: The size of a cache entry, including
248 * struct mb_cache_entry
249 * @indexes_count: number of additional indexes in the cache. Must equal
250 * MB_CACHE_INDEXES_COUNT if the number of indexes is
251 * hardwired.
252 * @bucket_bits: log2(number of hash buckets) 214 * @bucket_bits: log2(number of hash buckets)
253 */ 215 */
254struct mb_cache * 216struct mb_cache *
255mb_cache_create(const char *name, struct mb_cache_op *cache_op, 217mb_cache_create(const char *name, int bucket_bits)
256 size_t entry_size, int indexes_count, int bucket_bits)
257{ 218{
258 int m=0, n, bucket_count = 1 << bucket_bits; 219 int n, bucket_count = 1 << bucket_bits;
259 struct mb_cache *cache = NULL; 220 struct mb_cache *cache = NULL;
260 221
261 if(entry_size < sizeof(struct mb_cache_entry) + 222 cache = kmalloc(sizeof(struct mb_cache), GFP_KERNEL);
262 indexes_count * sizeof(((struct mb_cache_entry *) 0)->e_indexes[0]))
263 return NULL;
264
265 cache = kmalloc(sizeof(struct mb_cache) +
266 indexes_count * sizeof(struct list_head), GFP_KERNEL);
267 if (!cache) 223 if (!cache)
268 goto fail; 224 return NULL;
269 cache->c_name = name; 225 cache->c_name = name;
270 cache->c_op.free = NULL;
271 if (cache_op)
272 cache->c_op.free = cache_op->free;
273 atomic_set(&cache->c_entry_count, 0); 226 atomic_set(&cache->c_entry_count, 0);
274 cache->c_bucket_bits = bucket_bits; 227 cache->c_bucket_bits = bucket_bits;
275#ifdef MB_CACHE_INDEXES_COUNT
276 mb_assert(indexes_count == MB_CACHE_INDEXES_COUNT);
277#else
278 cache->c_indexes_count = indexes_count;
279#endif
280 cache->c_block_hash = kmalloc(bucket_count * sizeof(struct list_head), 228 cache->c_block_hash = kmalloc(bucket_count * sizeof(struct list_head),
281 GFP_KERNEL); 229 GFP_KERNEL);
282 if (!cache->c_block_hash) 230 if (!cache->c_block_hash)
283 goto fail; 231 goto fail;
284 for (n=0; n<bucket_count; n++) 232 for (n=0; n<bucket_count; n++)
285 INIT_LIST_HEAD(&cache->c_block_hash[n]); 233 INIT_LIST_HEAD(&cache->c_block_hash[n]);
286 for (m=0; m<indexes_count; m++) { 234 cache->c_index_hash = kmalloc(bucket_count * sizeof(struct list_head),
287 cache->c_indexes_hash[m] = kmalloc(bucket_count * 235 GFP_KERNEL);
288 sizeof(struct list_head), 236 if (!cache->c_index_hash)
289 GFP_KERNEL); 237 goto fail;
290 if (!cache->c_indexes_hash[m]) 238 for (n=0; n<bucket_count; n++)
291 goto fail; 239 INIT_LIST_HEAD(&cache->c_index_hash[n]);
292 for (n=0; n<bucket_count; n++) 240 cache->c_entry_cache = kmem_cache_create(name,
293 INIT_LIST_HEAD(&cache->c_indexes_hash[m][n]); 241 sizeof(struct mb_cache_entry), 0,
294 }
295 cache->c_entry_cache = kmem_cache_create(name, entry_size, 0,
296 SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD, NULL); 242 SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD, NULL);
297 if (!cache->c_entry_cache) 243 if (!cache->c_entry_cache)
298 goto fail; 244 goto fail2;
299 245
300 spin_lock(&mb_cache_spinlock); 246 spin_lock(&mb_cache_spinlock);
301 list_add(&cache->c_cache_list, &mb_cache_list); 247 list_add(&cache->c_cache_list, &mb_cache_list);
302 spin_unlock(&mb_cache_spinlock); 248 spin_unlock(&mb_cache_spinlock);
303 return cache; 249 return cache;
304 250
251fail2:
252 kfree(cache->c_index_hash);
253
305fail: 254fail:
306 if (cache) { 255 kfree(cache->c_block_hash);
307 while (--m >= 0) 256 kfree(cache);
308 kfree(cache->c_indexes_hash[m]);
309 kfree(cache->c_block_hash);
310 kfree(cache);
311 }
312 return NULL; 257 return NULL;
313} 258}
314 259
@@ -357,7 +302,6 @@ mb_cache_destroy(struct mb_cache *cache)
357{ 302{
358 LIST_HEAD(free_list); 303 LIST_HEAD(free_list);
359 struct list_head *l, *ltmp; 304 struct list_head *l, *ltmp;
360 int n;
361 305
362 spin_lock(&mb_cache_spinlock); 306 spin_lock(&mb_cache_spinlock);
363 list_for_each_safe(l, ltmp, &mb_cache_lru_list) { 307 list_for_each_safe(l, ltmp, &mb_cache_lru_list) {
@@ -384,8 +328,7 @@ mb_cache_destroy(struct mb_cache *cache)
384 328
385 kmem_cache_destroy(cache->c_entry_cache); 329 kmem_cache_destroy(cache->c_entry_cache);
386 330
387 for (n=0; n < mb_cache_indexes(cache); n++) 331 kfree(cache->c_index_hash);
388 kfree(cache->c_indexes_hash[n]);
389 kfree(cache->c_block_hash); 332 kfree(cache->c_block_hash);
390 kfree(cache); 333 kfree(cache);
391} 334}
@@ -429,17 +372,16 @@ mb_cache_entry_alloc(struct mb_cache *cache, gfp_t gfp_flags)
429 * 372 *
430 * @bdev: device the cache entry belongs to 373 * @bdev: device the cache entry belongs to
431 * @block: block number 374 * @block: block number
432 * @keys: array of additional keys. There must be indexes_count entries 375 * @key: lookup key
433 * in the array (as specified when creating the cache).
434 */ 376 */
435int 377int
436mb_cache_entry_insert(struct mb_cache_entry *ce, struct block_device *bdev, 378mb_cache_entry_insert(struct mb_cache_entry *ce, struct block_device *bdev,
437 sector_t block, unsigned int keys[]) 379 sector_t block, unsigned int key)
438{ 380{
439 struct mb_cache *cache = ce->e_cache; 381 struct mb_cache *cache = ce->e_cache;
440 unsigned int bucket; 382 unsigned int bucket;
441 struct list_head *l; 383 struct list_head *l;
442 int error = -EBUSY, n; 384 int error = -EBUSY;
443 385
444 bucket = hash_long((unsigned long)bdev + (block & 0xffffffff), 386 bucket = hash_long((unsigned long)bdev + (block & 0xffffffff),
445 cache->c_bucket_bits); 387 cache->c_bucket_bits);
@@ -454,12 +396,9 @@ mb_cache_entry_insert(struct mb_cache_entry *ce, struct block_device *bdev,
454 ce->e_bdev = bdev; 396 ce->e_bdev = bdev;
455 ce->e_block = block; 397 ce->e_block = block;
456 list_add(&ce->e_block_list, &cache->c_block_hash[bucket]); 398 list_add(&ce->e_block_list, &cache->c_block_hash[bucket]);
457 for (n=0; n<mb_cache_indexes(cache); n++) { 399 ce->e_index.o_key = key;
458 ce->e_indexes[n].o_key = keys[n]; 400 bucket = hash_long(key, cache->c_bucket_bits);
459 bucket = hash_long(keys[n], cache->c_bucket_bits); 401 list_add(&ce->e_index.o_list, &cache->c_index_hash[bucket]);
460 list_add(&ce->e_indexes[n].o_list,
461 &cache->c_indexes_hash[n][bucket]);
462 }
463 error = 0; 402 error = 0;
464out: 403out:
465 spin_unlock(&mb_cache_spinlock); 404 spin_unlock(&mb_cache_spinlock);
@@ -555,13 +494,12 @@ cleanup:
555 494
556static struct mb_cache_entry * 495static struct mb_cache_entry *
557__mb_cache_entry_find(struct list_head *l, struct list_head *head, 496__mb_cache_entry_find(struct list_head *l, struct list_head *head,
558 int index, struct block_device *bdev, unsigned int key) 497 struct block_device *bdev, unsigned int key)
559{ 498{
560 while (l != head) { 499 while (l != head) {
561 struct mb_cache_entry *ce = 500 struct mb_cache_entry *ce =
562 list_entry(l, struct mb_cache_entry, 501 list_entry(l, struct mb_cache_entry, e_index.o_list);
563 e_indexes[index].o_list); 502 if (ce->e_bdev == bdev && ce->e_index.o_key == key) {
564 if (ce->e_bdev == bdev && ce->e_indexes[index].o_key == key) {
565 DEFINE_WAIT(wait); 503 DEFINE_WAIT(wait);
566 504
567 if (!list_empty(&ce->e_lru_list)) 505 if (!list_empty(&ce->e_lru_list))
@@ -603,23 +541,20 @@ __mb_cache_entry_find(struct list_head *l, struct list_head *head,
603 * returned cache entry is locked for shared access ("multiple readers"). 541 * returned cache entry is locked for shared access ("multiple readers").
604 * 542 *
605 * @cache: the cache to search 543 * @cache: the cache to search
606 * @index: the number of the additonal index to search (0<=index<indexes_count)
607 * @bdev: the device the cache entry should belong to 544 * @bdev: the device the cache entry should belong to
608 * @key: the key in the index 545 * @key: the key in the index
609 */ 546 */
610struct mb_cache_entry * 547struct mb_cache_entry *
611mb_cache_entry_find_first(struct mb_cache *cache, int index, 548mb_cache_entry_find_first(struct mb_cache *cache, struct block_device *bdev,
612 struct block_device *bdev, unsigned int key) 549 unsigned int key)
613{ 550{
614 unsigned int bucket = hash_long(key, cache->c_bucket_bits); 551 unsigned int bucket = hash_long(key, cache->c_bucket_bits);
615 struct list_head *l; 552 struct list_head *l;
616 struct mb_cache_entry *ce; 553 struct mb_cache_entry *ce;
617 554
618 mb_assert(index < mb_cache_indexes(cache));
619 spin_lock(&mb_cache_spinlock); 555 spin_lock(&mb_cache_spinlock);
620 l = cache->c_indexes_hash[index][bucket].next; 556 l = cache->c_index_hash[bucket].next;
621 ce = __mb_cache_entry_find(l, &cache->c_indexes_hash[index][bucket], 557 ce = __mb_cache_entry_find(l, &cache->c_index_hash[bucket], bdev, key);
622 index, bdev, key);
623 spin_unlock(&mb_cache_spinlock); 558 spin_unlock(&mb_cache_spinlock);
624 return ce; 559 return ce;
625} 560}
@@ -640,12 +575,11 @@ mb_cache_entry_find_first(struct mb_cache *cache, int index,
640 * } 575 * }
641 * 576 *
642 * @prev: The previous match 577 * @prev: The previous match
643 * @index: the number of the additonal index to search (0<=index<indexes_count)
644 * @bdev: the device the cache entry should belong to 578 * @bdev: the device the cache entry should belong to
645 * @key: the key in the index 579 * @key: the key in the index
646 */ 580 */
647struct mb_cache_entry * 581struct mb_cache_entry *
648mb_cache_entry_find_next(struct mb_cache_entry *prev, int index, 582mb_cache_entry_find_next(struct mb_cache_entry *prev,
649 struct block_device *bdev, unsigned int key) 583 struct block_device *bdev, unsigned int key)
650{ 584{
651 struct mb_cache *cache = prev->e_cache; 585 struct mb_cache *cache = prev->e_cache;
@@ -653,11 +587,9 @@ mb_cache_entry_find_next(struct mb_cache_entry *prev, int index,
653 struct list_head *l; 587 struct list_head *l;
654 struct mb_cache_entry *ce; 588 struct mb_cache_entry *ce;
655 589
656 mb_assert(index < mb_cache_indexes(cache));
657 spin_lock(&mb_cache_spinlock); 590 spin_lock(&mb_cache_spinlock);
658 l = prev->e_indexes[index].o_list.next; 591 l = prev->e_index.o_list.next;
659 ce = __mb_cache_entry_find(l, &cache->c_indexes_hash[index][bucket], 592 ce = __mb_cache_entry_find(l, &cache->c_index_hash[bucket], bdev, key);
660 index, bdev, key);
661 __mb_cache_entry_release_unlock(prev); 593 __mb_cache_entry_release_unlock(prev);
662 return ce; 594 return ce;
663} 595}