Commit | Line | Data |
---|---|---|
cafe5635 KO |
1 | /* |
2 | * Main bcache entry point - handle a read or a write request and decide what to | |
3 | * do with it; the make_request functions are called by the block layer. | |
4 | * | |
5 | * Copyright 2010, 2011 Kent Overstreet <kent.overstreet@gmail.com> | |
6 | * Copyright 2012 Google, Inc. | |
7 | */ | |
8 | ||
9 | #include "bcache.h" | |
10 | #include "btree.h" | |
11 | #include "debug.h" | |
12 | #include "request.h" | |
279afbad | 13 | #include "writeback.h" |
cafe5635 | 14 | |
cafe5635 KO |
15 | #include <linux/module.h> |
16 | #include <linux/hash.h> | |
17 | #include <linux/random.h> | |
cafe5635 KO |
18 | |
19 | #include <trace/events/bcache.h> | |
20 | ||
21 | #define CUTOFF_CACHE_ADD 95 | |
22 | #define CUTOFF_CACHE_READA 90 | |
cafe5635 KO |
23 | |
24 | struct kmem_cache *bch_search_cache; | |
25 | ||
a34a8bfd KO |
26 | static void bch_data_insert_start(struct closure *); |
27 | ||
cafe5635 KO |
28 | static unsigned cache_mode(struct cached_dev *dc, struct bio *bio) |
29 | { | |
cafe5635 KO |
30 | return BDEV_CACHE_MODE(&dc->sb); |
31 | } | |
32 | ||
33 | static bool verify(struct cached_dev *dc, struct bio *bio) | |
34 | { | |
cafe5635 KO |
35 | return dc->verify; |
36 | } | |
37 | ||
38 | static void bio_csum(struct bio *bio, struct bkey *k) | |
39 | { | |
7988613b KO |
40 | struct bio_vec bv; |
41 | struct bvec_iter iter; | |
cafe5635 | 42 | uint64_t csum = 0; |
cafe5635 | 43 | |
7988613b KO |
44 | bio_for_each_segment(bv, bio, iter) { |
45 | void *d = kmap(bv.bv_page) + bv.bv_offset; | |
46 | csum = bch_crc64_update(csum, d, bv.bv_len); | |
47 | kunmap(bv.bv_page); | |
cafe5635 KO |
48 | } |
49 | ||
50 | k->ptr[KEY_PTRS(k)] = csum & (~0ULL >> 1); | |
51 | } | |
52 | ||
53 | /* Insert data into cache */ | |
54 | ||
a34a8bfd | 55 | static void bch_data_insert_keys(struct closure *cl) |
cafe5635 | 56 | { |
220bb38c | 57 | struct data_insert_op *op = container_of(cl, struct data_insert_op, cl); |
c18536a7 | 58 | atomic_t *journal_ref = NULL; |
220bb38c | 59 | struct bkey *replace_key = op->replace ? &op->replace_key : NULL; |
6054c6d4 | 60 | int ret; |
cafe5635 | 61 | |
a34a8bfd KO |
62 | /* |
63 | * If we're looping, might already be waiting on | |
64 | * another journal write - can't wait on more than one journal write at | |
65 | * a time | |
66 | * | |
67 | * XXX: this looks wrong | |
68 | */ | |
69 | #if 0 | |
70 | while (atomic_read(&s->cl.remaining) & CLOSURE_WAITING) | |
71 | closure_sync(&s->cl); | |
72 | #endif | |
cafe5635 | 73 | |
220bb38c KO |
74 | if (!op->replace) |
75 | journal_ref = bch_journal(op->c, &op->insert_keys, | |
76 | op->flush_journal ? cl : NULL); | |
cafe5635 | 77 | |
220bb38c | 78 | ret = bch_btree_insert(op->c, &op->insert_keys, |
6054c6d4 KO |
79 | journal_ref, replace_key); |
80 | if (ret == -ESRCH) { | |
220bb38c | 81 | op->replace_collision = true; |
6054c6d4 | 82 | } else if (ret) { |
220bb38c KO |
83 | op->error = -ENOMEM; |
84 | op->insert_data_done = true; | |
a34a8bfd | 85 | } |
cafe5635 | 86 | |
c18536a7 KO |
87 | if (journal_ref) |
88 | atomic_dec_bug(journal_ref); | |
cafe5635 | 89 | |
220bb38c | 90 | if (!op->insert_data_done) |
da415a09 | 91 | continue_at(cl, bch_data_insert_start, op->wq); |
cafe5635 | 92 | |
220bb38c | 93 | bch_keylist_free(&op->insert_keys); |
a34a8bfd | 94 | closure_return(cl); |
cafe5635 KO |
95 | } |
96 | ||
085d2a3d KO |
97 | static int bch_keylist_realloc(struct keylist *l, unsigned u64s, |
98 | struct cache_set *c) | |
99 | { | |
100 | size_t oldsize = bch_keylist_nkeys(l); | |
101 | size_t newsize = oldsize + u64s; | |
102 | ||
103 | /* | |
104 | * The journalling code doesn't handle the case where the keys to insert | |
105 | * is bigger than an empty write: If we just return -ENOMEM here, | |
106 | * bio_insert() and bio_invalidate() will insert the keys created so far | |
107 | * and finish the rest when the keylist is empty. | |
108 | */ | |
109 | if (newsize * sizeof(uint64_t) > block_bytes(c) - sizeof(struct jset)) | |
110 | return -ENOMEM; | |
111 | ||
112 | return __bch_keylist_realloc(l, u64s); | |
113 | } | |
114 | ||
a34a8bfd KO |
115 | static void bch_data_invalidate(struct closure *cl) |
116 | { | |
220bb38c KO |
117 | struct data_insert_op *op = container_of(cl, struct data_insert_op, cl); |
118 | struct bio *bio = op->bio; | |
a34a8bfd KO |
119 | |
120 | pr_debug("invalidating %i sectors from %llu", | |
4f024f37 | 121 | bio_sectors(bio), (uint64_t) bio->bi_iter.bi_sector); |
a34a8bfd KO |
122 | |
123 | while (bio_sectors(bio)) { | |
81ab4190 KO |
124 | unsigned sectors = min(bio_sectors(bio), |
125 | 1U << (KEY_SIZE_BITS - 1)); | |
a34a8bfd | 126 | |
085d2a3d | 127 | if (bch_keylist_realloc(&op->insert_keys, 2, op->c)) |
a34a8bfd KO |
128 | goto out; |
129 | ||
4f024f37 KO |
130 | bio->bi_iter.bi_sector += sectors; |
131 | bio->bi_iter.bi_size -= sectors << 9; | |
a34a8bfd | 132 | |
220bb38c | 133 | bch_keylist_add(&op->insert_keys, |
4f024f37 | 134 | &KEY(op->inode, bio->bi_iter.bi_sector, sectors)); |
a34a8bfd KO |
135 | } |
136 | ||
220bb38c | 137 | op->insert_data_done = true; |
a34a8bfd KO |
138 | bio_put(bio); |
139 | out: | |
da415a09 | 140 | continue_at(cl, bch_data_insert_keys, op->wq); |
a34a8bfd KO |
141 | } |
142 | ||
143 | static void bch_data_insert_error(struct closure *cl) | |
cafe5635 | 144 | { |
220bb38c | 145 | struct data_insert_op *op = container_of(cl, struct data_insert_op, cl); |
cafe5635 KO |
146 | |
147 | /* | |
148 | * Our data write just errored, which means we've got a bunch of keys to | |
149 | * insert that point to data that wasn't succesfully written. | |
150 | * | |
151 | * We don't have to insert those keys but we still have to invalidate | |
152 | * that region of the cache - so, if we just strip off all the pointers | |
153 | * from the keys we'll accomplish just that. | |
154 | */ | |
155 | ||
220bb38c | 156 | struct bkey *src = op->insert_keys.keys, *dst = op->insert_keys.keys; |
cafe5635 | 157 | |
220bb38c | 158 | while (src != op->insert_keys.top) { |
cafe5635 KO |
159 | struct bkey *n = bkey_next(src); |
160 | ||
161 | SET_KEY_PTRS(src, 0); | |
c2f95ae2 | 162 | memmove(dst, src, bkey_bytes(src)); |
cafe5635 KO |
163 | |
164 | dst = bkey_next(dst); | |
165 | src = n; | |
166 | } | |
167 | ||
220bb38c | 168 | op->insert_keys.top = dst; |
cafe5635 | 169 | |
a34a8bfd | 170 | bch_data_insert_keys(cl); |
cafe5635 KO |
171 | } |
172 | ||
a34a8bfd | 173 | static void bch_data_insert_endio(struct bio *bio, int error) |
cafe5635 KO |
174 | { |
175 | struct closure *cl = bio->bi_private; | |
220bb38c | 176 | struct data_insert_op *op = container_of(cl, struct data_insert_op, cl); |
cafe5635 KO |
177 | |
178 | if (error) { | |
179 | /* TODO: We could try to recover from this. */ | |
220bb38c KO |
180 | if (op->writeback) |
181 | op->error = error; | |
182 | else if (!op->replace) | |
da415a09 | 183 | set_closure_fn(cl, bch_data_insert_error, op->wq); |
cafe5635 KO |
184 | else |
185 | set_closure_fn(cl, NULL, NULL); | |
186 | } | |
187 | ||
220bb38c | 188 | bch_bbio_endio(op->c, bio, error, "writing data to cache"); |
cafe5635 KO |
189 | } |
190 | ||
a34a8bfd | 191 | static void bch_data_insert_start(struct closure *cl) |
cafe5635 | 192 | { |
220bb38c KO |
193 | struct data_insert_op *op = container_of(cl, struct data_insert_op, cl); |
194 | struct bio *bio = op->bio, *n; | |
cafe5635 | 195 | |
220bb38c KO |
196 | if (atomic_sub_return(bio_sectors(bio), &op->c->sectors_to_gc) < 0) { |
197 | set_gc_sectors(op->c); | |
198 | wake_up_gc(op->c); | |
cafe5635 KO |
199 | } |
200 | ||
e3b4825b NS |
201 | if (op->bypass) |
202 | return bch_data_invalidate(cl); | |
203 | ||
54d12f2b KO |
204 | /* |
205 | * Journal writes are marked REQ_FLUSH; if the original write was a | |
206 | * flush, it'll wait on the journal write. | |
207 | */ | |
208 | bio->bi_rw &= ~(REQ_FLUSH|REQ_FUA); | |
209 | ||
cafe5635 KO |
210 | do { |
211 | unsigned i; | |
212 | struct bkey *k; | |
220bb38c | 213 | struct bio_set *split = op->c->bio_split; |
cafe5635 KO |
214 | |
215 | /* 1 for the device pointer and 1 for the chksum */ | |
220bb38c | 216 | if (bch_keylist_realloc(&op->insert_keys, |
085d2a3d | 217 | 3 + (op->csum ? 1 : 0), |
220bb38c | 218 | op->c)) |
da415a09 | 219 | continue_at(cl, bch_data_insert_keys, op->wq); |
cafe5635 | 220 | |
220bb38c | 221 | k = op->insert_keys.top; |
cafe5635 | 222 | bkey_init(k); |
220bb38c | 223 | SET_KEY_INODE(k, op->inode); |
4f024f37 | 224 | SET_KEY_OFFSET(k, bio->bi_iter.bi_sector); |
cafe5635 | 225 | |
2599b53b KO |
226 | if (!bch_alloc_sectors(op->c, k, bio_sectors(bio), |
227 | op->write_point, op->write_prio, | |
228 | op->writeback)) | |
cafe5635 KO |
229 | goto err; |
230 | ||
20d0189b | 231 | n = bio_next_split(bio, KEY_SIZE(k), GFP_NOIO, split); |
cafe5635 | 232 | |
a34a8bfd | 233 | n->bi_end_io = bch_data_insert_endio; |
cafe5635 KO |
234 | n->bi_private = cl; |
235 | ||
220bb38c | 236 | if (op->writeback) { |
cafe5635 KO |
237 | SET_KEY_DIRTY(k, true); |
238 | ||
239 | for (i = 0; i < KEY_PTRS(k); i++) | |
220bb38c | 240 | SET_GC_MARK(PTR_BUCKET(op->c, k, i), |
cafe5635 KO |
241 | GC_MARK_DIRTY); |
242 | } | |
243 | ||
220bb38c | 244 | SET_KEY_CSUM(k, op->csum); |
cafe5635 KO |
245 | if (KEY_CSUM(k)) |
246 | bio_csum(n, k); | |
247 | ||
c37511b8 | 248 | trace_bcache_cache_insert(k); |
220bb38c | 249 | bch_keylist_push(&op->insert_keys); |
cafe5635 | 250 | |
cafe5635 | 251 | n->bi_rw |= REQ_WRITE; |
220bb38c | 252 | bch_submit_bbio(n, op->c, k, 0); |
cafe5635 KO |
253 | } while (n != bio); |
254 | ||
220bb38c | 255 | op->insert_data_done = true; |
da415a09 | 256 | continue_at(cl, bch_data_insert_keys, op->wq); |
cafe5635 KO |
257 | err: |
258 | /* bch_alloc_sectors() blocks if s->writeback = true */ | |
220bb38c | 259 | BUG_ON(op->writeback); |
cafe5635 KO |
260 | |
261 | /* | |
262 | * But if it's not a writeback write we'd rather just bail out if | |
263 | * there aren't any buckets ready to write to - it might take awhile and | |
264 | * we might be starving btree writes for gc or something. | |
265 | */ | |
266 | ||
220bb38c | 267 | if (!op->replace) { |
cafe5635 KO |
268 | /* |
269 | * Writethrough write: We can't complete the write until we've | |
270 | * updated the index. But we don't want to delay the write while | |
271 | * we wait for buckets to be freed up, so just invalidate the | |
272 | * rest of the write. | |
273 | */ | |
220bb38c | 274 | op->bypass = true; |
a34a8bfd | 275 | return bch_data_invalidate(cl); |
cafe5635 KO |
276 | } else { |
277 | /* | |
278 | * From a cache miss, we can just insert the keys for the data | |
279 | * we have written or bail out if we didn't do anything. | |
280 | */ | |
220bb38c | 281 | op->insert_data_done = true; |
cafe5635 KO |
282 | bio_put(bio); |
283 | ||
220bb38c | 284 | if (!bch_keylist_empty(&op->insert_keys)) |
da415a09 | 285 | continue_at(cl, bch_data_insert_keys, op->wq); |
cafe5635 KO |
286 | else |
287 | closure_return(cl); | |
288 | } | |
289 | } | |
290 | ||
291 | /** | |
a34a8bfd | 292 | * bch_data_insert - stick some data in the cache |
cafe5635 KO |
293 | * |
294 | * This is the starting point for any data to end up in a cache device; it could | |
295 | * be from a normal write, or a writeback write, or a write to a flash only | |
296 | * volume - it's also used by the moving garbage collector to compact data in | |
297 | * mostly empty buckets. | |
298 | * | |
299 | * It first writes the data to the cache, creating a list of keys to be inserted | |
300 | * (if the data had to be fragmented there will be multiple keys); after the | |
301 | * data is written it calls bch_journal, and after the keys have been added to | |
302 | * the next journal write they're inserted into the btree. | |
303 | * | |
c18536a7 | 304 | * It inserts the data in s->cache_bio; bi_sector is used for the key offset, |
cafe5635 KO |
305 | * and op->inode is used for the key inode. |
306 | * | |
c18536a7 KO |
307 | * If s->bypass is true, instead of inserting the data it invalidates the |
308 | * region of the cache represented by s->cache_bio and op->inode. | |
cafe5635 | 309 | */ |
a34a8bfd | 310 | void bch_data_insert(struct closure *cl) |
cafe5635 | 311 | { |
220bb38c | 312 | struct data_insert_op *op = container_of(cl, struct data_insert_op, cl); |
cafe5635 | 313 | |
60ae81ee SP |
314 | trace_bcache_write(op->c, op->inode, op->bio, |
315 | op->writeback, op->bypass); | |
220bb38c KO |
316 | |
317 | bch_keylist_init(&op->insert_keys); | |
318 | bio_get(op->bio); | |
a34a8bfd | 319 | bch_data_insert_start(cl); |
cafe5635 KO |
320 | } |
321 | ||
220bb38c KO |
322 | /* Congested? */ |
323 | ||
324 | unsigned bch_get_congested(struct cache_set *c) | |
325 | { | |
326 | int i; | |
327 | long rand; | |
328 | ||
329 | if (!c->congested_read_threshold_us && | |
330 | !c->congested_write_threshold_us) | |
331 | return 0; | |
332 | ||
333 | i = (local_clock_us() - c->congested_last_us) / 1024; | |
334 | if (i < 0) | |
335 | return 0; | |
336 | ||
337 | i += atomic_read(&c->congested); | |
338 | if (i >= 0) | |
339 | return 0; | |
340 | ||
341 | i += CONGESTED_MAX; | |
342 | ||
343 | if (i > 0) | |
344 | i = fract_exp_two(i, 6); | |
345 | ||
346 | rand = get_random_int(); | |
347 | i -= bitmap_weight(&rand, BITS_PER_LONG); | |
348 | ||
349 | return i > 0 ? i : 1; | |
350 | } | |
351 | ||
352 | static void add_sequential(struct task_struct *t) | |
353 | { | |
354 | ewma_add(t->sequential_io_avg, | |
355 | t->sequential_io, 8, 0); | |
356 | ||
357 | t->sequential_io = 0; | |
358 | } | |
359 | ||
360 | static struct hlist_head *iohash(struct cached_dev *dc, uint64_t k) | |
361 | { | |
362 | return &dc->io_hash[hash_64(k, RECENT_IO_BITS)]; | |
363 | } | |
364 | ||
365 | static bool check_should_bypass(struct cached_dev *dc, struct bio *bio) | |
366 | { | |
367 | struct cache_set *c = dc->disk.c; | |
368 | unsigned mode = cache_mode(dc, bio); | |
369 | unsigned sectors, congested = bch_get_congested(c); | |
370 | struct task_struct *task = current; | |
8aee1220 | 371 | struct io *i; |
220bb38c | 372 | |
c4d951dd | 373 | if (test_bit(BCACHE_DEV_DETACHING, &dc->disk.flags) || |
220bb38c KO |
374 | c->gc_stats.in_use > CUTOFF_CACHE_ADD || |
375 | (bio->bi_rw & REQ_DISCARD)) | |
376 | goto skip; | |
377 | ||
378 | if (mode == CACHE_MODE_NONE || | |
379 | (mode == CACHE_MODE_WRITEAROUND && | |
380 | (bio->bi_rw & REQ_WRITE))) | |
381 | goto skip; | |
382 | ||
4f024f37 | 383 | if (bio->bi_iter.bi_sector & (c->sb.block_size - 1) || |
220bb38c KO |
384 | bio_sectors(bio) & (c->sb.block_size - 1)) { |
385 | pr_debug("skipping unaligned io"); | |
386 | goto skip; | |
387 | } | |
388 | ||
5ceaaad7 KO |
389 | if (bypass_torture_test(dc)) { |
390 | if ((get_random_int() & 3) == 3) | |
391 | goto skip; | |
392 | else | |
393 | goto rescale; | |
394 | } | |
395 | ||
220bb38c KO |
396 | if (!congested && !dc->sequential_cutoff) |
397 | goto rescale; | |
398 | ||
399 | if (!congested && | |
400 | mode == CACHE_MODE_WRITEBACK && | |
401 | (bio->bi_rw & REQ_WRITE) && | |
402 | (bio->bi_rw & REQ_SYNC)) | |
403 | goto rescale; | |
404 | ||
8aee1220 | 405 | spin_lock(&dc->io_lock); |
220bb38c | 406 | |
4f024f37 KO |
407 | hlist_for_each_entry(i, iohash(dc, bio->bi_iter.bi_sector), hash) |
408 | if (i->last == bio->bi_iter.bi_sector && | |
8aee1220 KO |
409 | time_before(jiffies, i->jiffies)) |
410 | goto found; | |
220bb38c | 411 | |
8aee1220 | 412 | i = list_first_entry(&dc->io_lru, struct io, lru); |
220bb38c | 413 | |
8aee1220 KO |
414 | add_sequential(task); |
415 | i->sequential = 0; | |
220bb38c | 416 | found: |
4f024f37 KO |
417 | if (i->sequential + bio->bi_iter.bi_size > i->sequential) |
418 | i->sequential += bio->bi_iter.bi_size; | |
220bb38c | 419 | |
8aee1220 KO |
420 | i->last = bio_end_sector(bio); |
421 | i->jiffies = jiffies + msecs_to_jiffies(5000); | |
422 | task->sequential_io = i->sequential; | |
220bb38c | 423 | |
8aee1220 KO |
424 | hlist_del(&i->hash); |
425 | hlist_add_head(&i->hash, iohash(dc, i->last)); | |
426 | list_move_tail(&i->lru, &dc->io_lru); | |
220bb38c | 427 | |
8aee1220 | 428 | spin_unlock(&dc->io_lock); |
220bb38c KO |
429 | |
430 | sectors = max(task->sequential_io, | |
431 | task->sequential_io_avg) >> 9; | |
432 | ||
433 | if (dc->sequential_cutoff && | |
434 | sectors >= dc->sequential_cutoff >> 9) { | |
435 | trace_bcache_bypass_sequential(bio); | |
436 | goto skip; | |
437 | } | |
438 | ||
439 | if (congested && sectors >= congested) { | |
440 | trace_bcache_bypass_congested(bio); | |
441 | goto skip; | |
442 | } | |
443 | ||
444 | rescale: | |
445 | bch_rescale_priorities(c, bio_sectors(bio)); | |
446 | return false; | |
447 | skip: | |
448 | bch_mark_sectors_bypassed(c, dc, bio_sectors(bio)); | |
449 | return true; | |
450 | } | |
451 | ||
2c1953e2 | 452 | /* Cache lookup */ |
cafe5635 | 453 | |
220bb38c KO |
454 | struct search { |
455 | /* Stack frame for bio_complete */ | |
456 | struct closure cl; | |
457 | ||
220bb38c KO |
458 | struct bbio bio; |
459 | struct bio *orig_bio; | |
460 | struct bio *cache_miss; | |
a5ae4300 | 461 | struct bcache_device *d; |
220bb38c KO |
462 | |
463 | unsigned insert_bio_sectors; | |
220bb38c | 464 | unsigned recoverable:1; |
220bb38c | 465 | unsigned write:1; |
5ceaaad7 | 466 | unsigned read_dirty_data:1; |
220bb38c KO |
467 | |
468 | unsigned long start_time; | |
469 | ||
470 | struct btree_op op; | |
471 | struct data_insert_op iop; | |
472 | }; | |
473 | ||
2c1953e2 | 474 | static void bch_cache_read_endio(struct bio *bio, int error) |
cafe5635 KO |
475 | { |
476 | struct bbio *b = container_of(bio, struct bbio, bio); | |
477 | struct closure *cl = bio->bi_private; | |
478 | struct search *s = container_of(cl, struct search, cl); | |
479 | ||
480 | /* | |
481 | * If the bucket was reused while our bio was in flight, we might have | |
482 | * read the wrong data. Set s->error but not error so it doesn't get | |
483 | * counted against the cache device, but we'll still reread the data | |
484 | * from the backing device. | |
485 | */ | |
486 | ||
487 | if (error) | |
220bb38c | 488 | s->iop.error = error; |
d56d000a KO |
489 | else if (!KEY_DIRTY(&b->key) && |
490 | ptr_stale(s->iop.c, &b->key, 0)) { | |
220bb38c KO |
491 | atomic_long_inc(&s->iop.c->cache_read_races); |
492 | s->iop.error = -EINTR; | |
cafe5635 KO |
493 | } |
494 | ||
220bb38c | 495 | bch_bbio_endio(s->iop.c, bio, error, "reading from cache"); |
cafe5635 KO |
496 | } |
497 | ||
2c1953e2 KO |
498 | /* |
499 | * Read from a single key, handling the initial cache miss if the key starts in | |
500 | * the middle of the bio | |
501 | */ | |
cc231966 | 502 | static int cache_lookup_fn(struct btree_op *op, struct btree *b, struct bkey *k) |
2c1953e2 KO |
503 | { |
504 | struct search *s = container_of(op, struct search, op); | |
cc231966 KO |
505 | struct bio *n, *bio = &s->bio.bio; |
506 | struct bkey *bio_key; | |
2c1953e2 | 507 | unsigned ptr; |
2c1953e2 | 508 | |
4f024f37 | 509 | if (bkey_cmp(k, &KEY(s->iop.inode, bio->bi_iter.bi_sector, 0)) <= 0) |
cc231966 KO |
510 | return MAP_CONTINUE; |
511 | ||
220bb38c | 512 | if (KEY_INODE(k) != s->iop.inode || |
4f024f37 | 513 | KEY_START(k) > bio->bi_iter.bi_sector) { |
cc231966 | 514 | unsigned bio_sectors = bio_sectors(bio); |
220bb38c | 515 | unsigned sectors = KEY_INODE(k) == s->iop.inode |
cc231966 | 516 | ? min_t(uint64_t, INT_MAX, |
4f024f37 | 517 | KEY_START(k) - bio->bi_iter.bi_sector) |
cc231966 KO |
518 | : INT_MAX; |
519 | ||
520 | int ret = s->d->cache_miss(b, s, bio, sectors); | |
521 | if (ret != MAP_CONTINUE) | |
522 | return ret; | |
523 | ||
524 | /* if this was a complete miss we shouldn't get here */ | |
525 | BUG_ON(bio_sectors <= sectors); | |
526 | } | |
527 | ||
528 | if (!KEY_SIZE(k)) | |
529 | return MAP_CONTINUE; | |
2c1953e2 KO |
530 | |
531 | /* XXX: figure out best pointer - for multiple cache devices */ | |
532 | ptr = 0; | |
533 | ||
534 | PTR_BUCKET(b->c, k, ptr)->prio = INITIAL_PRIO; | |
535 | ||
5ceaaad7 KO |
536 | if (KEY_DIRTY(k)) |
537 | s->read_dirty_data = true; | |
538 | ||
20d0189b KO |
539 | n = bio_next_split(bio, min_t(uint64_t, INT_MAX, |
540 | KEY_OFFSET(k) - bio->bi_iter.bi_sector), | |
541 | GFP_NOIO, s->d->bio_split); | |
2c1953e2 | 542 | |
cc231966 KO |
543 | bio_key = &container_of(n, struct bbio, bio)->key; |
544 | bch_bkey_copy_single_ptr(bio_key, k, ptr); | |
2c1953e2 | 545 | |
4f024f37 | 546 | bch_cut_front(&KEY(s->iop.inode, n->bi_iter.bi_sector, 0), bio_key); |
220bb38c | 547 | bch_cut_back(&KEY(s->iop.inode, bio_end_sector(n), 0), bio_key); |
2c1953e2 | 548 | |
cc231966 KO |
549 | n->bi_end_io = bch_cache_read_endio; |
550 | n->bi_private = &s->cl; | |
2c1953e2 | 551 | |
cc231966 KO |
552 | /* |
553 | * The bucket we're reading from might be reused while our bio | |
554 | * is in flight, and we could then end up reading the wrong | |
555 | * data. | |
556 | * | |
557 | * We guard against this by checking (in cache_read_endio()) if | |
558 | * the pointer is stale again; if so, we treat it as an error | |
559 | * and reread from the backing device (but we don't pass that | |
560 | * error up anywhere). | |
561 | */ | |
2c1953e2 | 562 | |
cc231966 KO |
563 | __bch_submit_bbio(n, b->c); |
564 | return n == bio ? MAP_DONE : MAP_CONTINUE; | |
2c1953e2 KO |
565 | } |
566 | ||
567 | static void cache_lookup(struct closure *cl) | |
568 | { | |
220bb38c | 569 | struct search *s = container_of(cl, struct search, iop.cl); |
2c1953e2 | 570 | struct bio *bio = &s->bio.bio; |
a5ae4300 | 571 | int ret; |
2c1953e2 | 572 | |
a5ae4300 | 573 | bch_btree_op_init(&s->op, -1); |
2c1953e2 | 574 | |
a5ae4300 KO |
575 | ret = bch_btree_map_keys(&s->op, s->iop.c, |
576 | &KEY(s->iop.inode, bio->bi_iter.bi_sector, 0), | |
577 | cache_lookup_fn, MAP_END_KEY); | |
2c1953e2 KO |
578 | if (ret == -EAGAIN) |
579 | continue_at(cl, cache_lookup, bcache_wq); | |
580 | ||
581 | closure_return(cl); | |
582 | } | |
583 | ||
584 | /* Common code for the make_request functions */ | |
585 | ||
586 | static void request_endio(struct bio *bio, int error) | |
587 | { | |
588 | struct closure *cl = bio->bi_private; | |
589 | ||
590 | if (error) { | |
591 | struct search *s = container_of(cl, struct search, cl); | |
220bb38c | 592 | s->iop.error = error; |
2c1953e2 KO |
593 | /* Only cache read errors are recoverable */ |
594 | s->recoverable = false; | |
595 | } | |
596 | ||
597 | bio_put(bio); | |
598 | closure_put(cl); | |
599 | } | |
600 | ||
cafe5635 KO |
601 | static void bio_complete(struct search *s) |
602 | { | |
603 | if (s->orig_bio) { | |
aae4933d GZ |
604 | generic_end_io_acct(bio_data_dir(s->orig_bio), |
605 | &s->d->disk->part0, s->start_time); | |
cafe5635 | 606 | |
220bb38c KO |
607 | trace_bcache_request_end(s->d, s->orig_bio); |
608 | bio_endio(s->orig_bio, s->iop.error); | |
cafe5635 KO |
609 | s->orig_bio = NULL; |
610 | } | |
611 | } | |
612 | ||
a5ae4300 | 613 | static void do_bio_hook(struct search *s, struct bio *orig_bio) |
cafe5635 KO |
614 | { |
615 | struct bio *bio = &s->bio.bio; | |
cafe5635 | 616 | |
ed9c47be | 617 | bio_init(bio); |
a5ae4300 | 618 | __bio_clone_fast(bio, orig_bio); |
cafe5635 KO |
619 | bio->bi_end_io = request_endio; |
620 | bio->bi_private = &s->cl; | |
ed9c47be | 621 | |
cafe5635 KO |
622 | atomic_set(&bio->bi_cnt, 3); |
623 | } | |
624 | ||
625 | static void search_free(struct closure *cl) | |
626 | { | |
627 | struct search *s = container_of(cl, struct search, cl); | |
628 | bio_complete(s); | |
629 | ||
220bb38c KO |
630 | if (s->iop.bio) |
631 | bio_put(s->iop.bio); | |
cafe5635 | 632 | |
cafe5635 KO |
633 | closure_debug_destroy(cl); |
634 | mempool_free(s, s->d->c->search); | |
635 | } | |
636 | ||
a5ae4300 KO |
637 | static inline struct search *search_alloc(struct bio *bio, |
638 | struct bcache_device *d) | |
cafe5635 | 639 | { |
0b93207a | 640 | struct search *s; |
0b93207a KO |
641 | |
642 | s = mempool_alloc(d->c->search, GFP_NOIO); | |
cafe5635 | 643 | |
a5ae4300 KO |
644 | closure_init(&s->cl, NULL); |
645 | do_bio_hook(s, bio); | |
cafe5635 | 646 | |
cafe5635 | 647 | s->orig_bio = bio; |
a5ae4300 KO |
648 | s->cache_miss = NULL; |
649 | s->d = d; | |
cafe5635 | 650 | s->recoverable = 1; |
a5ae4300 KO |
651 | s->write = (bio->bi_rw & REQ_WRITE) != 0; |
652 | s->read_dirty_data = 0; | |
cafe5635 | 653 | s->start_time = jiffies; |
a5ae4300 KO |
654 | |
655 | s->iop.c = d->c; | |
656 | s->iop.bio = NULL; | |
657 | s->iop.inode = d->id; | |
658 | s->iop.write_point = hash_long((unsigned long) current, 16); | |
659 | s->iop.write_prio = 0; | |
660 | s->iop.error = 0; | |
661 | s->iop.flags = 0; | |
662 | s->iop.flush_journal = (bio->bi_rw & (REQ_FLUSH|REQ_FUA)) != 0; | |
da415a09 | 663 | s->iop.wq = bcache_wq; |
cafe5635 | 664 | |
cafe5635 KO |
665 | return s; |
666 | } | |
667 | ||
cafe5635 KO |
668 | /* Cached devices */ |
669 | ||
670 | static void cached_dev_bio_complete(struct closure *cl) | |
671 | { | |
672 | struct search *s = container_of(cl, struct search, cl); | |
673 | struct cached_dev *dc = container_of(s->d, struct cached_dev, disk); | |
674 | ||
675 | search_free(cl); | |
676 | cached_dev_put(dc); | |
677 | } | |
678 | ||
679 | /* Process reads */ | |
680 | ||
cdd972b1 | 681 | static void cached_dev_cache_miss_done(struct closure *cl) |
cafe5635 KO |
682 | { |
683 | struct search *s = container_of(cl, struct search, cl); | |
684 | ||
220bb38c KO |
685 | if (s->iop.replace_collision) |
686 | bch_mark_cache_miss_collision(s->iop.c, s->d); | |
cafe5635 | 687 | |
220bb38c | 688 | if (s->iop.bio) { |
cafe5635 KO |
689 | int i; |
690 | struct bio_vec *bv; | |
691 | ||
220bb38c | 692 | bio_for_each_segment_all(bv, s->iop.bio, i) |
cafe5635 KO |
693 | __free_page(bv->bv_page); |
694 | } | |
695 | ||
696 | cached_dev_bio_complete(cl); | |
697 | } | |
698 | ||
cdd972b1 | 699 | static void cached_dev_read_error(struct closure *cl) |
cafe5635 KO |
700 | { |
701 | struct search *s = container_of(cl, struct search, cl); | |
cdd972b1 | 702 | struct bio *bio = &s->bio.bio; |
cafe5635 KO |
703 | |
704 | if (s->recoverable) { | |
c37511b8 KO |
705 | /* Retry from the backing device: */ |
706 | trace_bcache_read_retry(s->orig_bio); | |
cafe5635 | 707 | |
220bb38c | 708 | s->iop.error = 0; |
a5ae4300 | 709 | do_bio_hook(s, s->orig_bio); |
cafe5635 KO |
710 | |
711 | /* XXX: invalidate cache */ | |
712 | ||
cdd972b1 | 713 | closure_bio_submit(bio, cl, s->d); |
cafe5635 KO |
714 | } |
715 | ||
cdd972b1 | 716 | continue_at(cl, cached_dev_cache_miss_done, NULL); |
cafe5635 KO |
717 | } |
718 | ||
cdd972b1 | 719 | static void cached_dev_read_done(struct closure *cl) |
cafe5635 KO |
720 | { |
721 | struct search *s = container_of(cl, struct search, cl); | |
722 | struct cached_dev *dc = container_of(s->d, struct cached_dev, disk); | |
723 | ||
724 | /* | |
cdd972b1 KO |
725 | * We had a cache miss; cache_bio now contains data ready to be inserted |
726 | * into the cache. | |
cafe5635 KO |
727 | * |
728 | * First, we copy the data we just read from cache_bio's bounce buffers | |
729 | * to the buffers the original bio pointed to: | |
730 | */ | |
731 | ||
220bb38c KO |
732 | if (s->iop.bio) { |
733 | bio_reset(s->iop.bio); | |
4f024f37 | 734 | s->iop.bio->bi_iter.bi_sector = s->cache_miss->bi_iter.bi_sector; |
220bb38c | 735 | s->iop.bio->bi_bdev = s->cache_miss->bi_bdev; |
4f024f37 | 736 | s->iop.bio->bi_iter.bi_size = s->insert_bio_sectors << 9; |
220bb38c | 737 | bch_bio_map(s->iop.bio, NULL); |
cafe5635 | 738 | |
220bb38c | 739 | bio_copy_data(s->cache_miss, s->iop.bio); |
cafe5635 KO |
740 | |
741 | bio_put(s->cache_miss); | |
742 | s->cache_miss = NULL; | |
743 | } | |
744 | ||
ed9c47be | 745 | if (verify(dc, &s->bio.bio) && s->recoverable && !s->read_dirty_data) |
220bb38c | 746 | bch_data_verify(dc, s->orig_bio); |
cafe5635 KO |
747 | |
748 | bio_complete(s); | |
749 | ||
220bb38c KO |
750 | if (s->iop.bio && |
751 | !test_bit(CACHE_SET_STOPPING, &s->iop.c->flags)) { | |
752 | BUG_ON(!s->iop.replace); | |
753 | closure_call(&s->iop.cl, bch_data_insert, NULL, cl); | |
cafe5635 KO |
754 | } |
755 | ||
cdd972b1 | 756 | continue_at(cl, cached_dev_cache_miss_done, NULL); |
cafe5635 KO |
757 | } |
758 | ||
cdd972b1 | 759 | static void cached_dev_read_done_bh(struct closure *cl) |
cafe5635 KO |
760 | { |
761 | struct search *s = container_of(cl, struct search, cl); | |
762 | struct cached_dev *dc = container_of(s->d, struct cached_dev, disk); | |
763 | ||
220bb38c KO |
764 | bch_mark_cache_accounting(s->iop.c, s->d, |
765 | !s->cache_miss, s->iop.bypass); | |
766 | trace_bcache_read(s->orig_bio, !s->cache_miss, s->iop.bypass); | |
cafe5635 | 767 | |
220bb38c | 768 | if (s->iop.error) |
cdd972b1 | 769 | continue_at_nobarrier(cl, cached_dev_read_error, bcache_wq); |
220bb38c | 770 | else if (s->iop.bio || verify(dc, &s->bio.bio)) |
cdd972b1 | 771 | continue_at_nobarrier(cl, cached_dev_read_done, bcache_wq); |
cafe5635 | 772 | else |
cdd972b1 | 773 | continue_at_nobarrier(cl, cached_dev_bio_complete, NULL); |
cafe5635 KO |
774 | } |
775 | ||
776 | static int cached_dev_cache_miss(struct btree *b, struct search *s, | |
777 | struct bio *bio, unsigned sectors) | |
778 | { | |
2c1953e2 | 779 | int ret = MAP_CONTINUE; |
e7c590eb | 780 | unsigned reada = 0; |
cafe5635 | 781 | struct cached_dev *dc = container_of(s->d, struct cached_dev, disk); |
cdd972b1 | 782 | struct bio *miss, *cache_bio; |
cafe5635 | 783 | |
220bb38c | 784 | if (s->cache_miss || s->iop.bypass) { |
20d0189b | 785 | miss = bio_next_split(bio, sectors, GFP_NOIO, s->d->bio_split); |
2c1953e2 | 786 | ret = miss == bio ? MAP_DONE : MAP_CONTINUE; |
e7c590eb KO |
787 | goto out_submit; |
788 | } | |
cafe5635 | 789 | |
e7c590eb KO |
790 | if (!(bio->bi_rw & REQ_RAHEAD) && |
791 | !(bio->bi_rw & REQ_META) && | |
220bb38c | 792 | s->iop.c->gc_stats.in_use < CUTOFF_CACHE_READA) |
e7c590eb KO |
793 | reada = min_t(sector_t, dc->readahead >> 9, |
794 | bdev_sectors(bio->bi_bdev) - bio_end_sector(bio)); | |
cafe5635 | 795 | |
220bb38c | 796 | s->insert_bio_sectors = min(sectors, bio_sectors(bio) + reada); |
cafe5635 | 797 | |
220bb38c | 798 | s->iop.replace_key = KEY(s->iop.inode, |
4f024f37 | 799 | bio->bi_iter.bi_sector + s->insert_bio_sectors, |
220bb38c | 800 | s->insert_bio_sectors); |
e7c590eb | 801 | |
220bb38c | 802 | ret = bch_btree_insert_check_key(b, &s->op, &s->iop.replace_key); |
e7c590eb KO |
803 | if (ret) |
804 | return ret; | |
805 | ||
220bb38c | 806 | s->iop.replace = true; |
1b207d80 | 807 | |
20d0189b | 808 | miss = bio_next_split(bio, sectors, GFP_NOIO, s->d->bio_split); |
2c1953e2 KO |
809 | |
810 | /* btree_search_recurse()'s btree iterator is no good anymore */ | |
811 | ret = miss == bio ? MAP_DONE : -EINTR; | |
cafe5635 | 812 | |
cdd972b1 | 813 | cache_bio = bio_alloc_bioset(GFP_NOWAIT, |
220bb38c | 814 | DIV_ROUND_UP(s->insert_bio_sectors, PAGE_SECTORS), |
cafe5635 | 815 | dc->disk.bio_split); |
cdd972b1 | 816 | if (!cache_bio) |
cafe5635 KO |
817 | goto out_submit; |
818 | ||
4f024f37 KO |
819 | cache_bio->bi_iter.bi_sector = miss->bi_iter.bi_sector; |
820 | cache_bio->bi_bdev = miss->bi_bdev; | |
821 | cache_bio->bi_iter.bi_size = s->insert_bio_sectors << 9; | |
cafe5635 | 822 | |
cdd972b1 KO |
823 | cache_bio->bi_end_io = request_endio; |
824 | cache_bio->bi_private = &s->cl; | |
cafe5635 | 825 | |
cdd972b1 KO |
826 | bch_bio_map(cache_bio, NULL); |
827 | if (bio_alloc_pages(cache_bio, __GFP_NOWARN|GFP_NOIO)) | |
cafe5635 KO |
828 | goto out_put; |
829 | ||
220bb38c KO |
830 | if (reada) |
831 | bch_mark_cache_readahead(s->iop.c, s->d); | |
832 | ||
cdd972b1 | 833 | s->cache_miss = miss; |
220bb38c | 834 | s->iop.bio = cache_bio; |
cdd972b1 KO |
835 | bio_get(cache_bio); |
836 | closure_bio_submit(cache_bio, &s->cl, s->d); | |
cafe5635 KO |
837 | |
838 | return ret; | |
839 | out_put: | |
cdd972b1 | 840 | bio_put(cache_bio); |
cafe5635 | 841 | out_submit: |
e7c590eb KO |
842 | miss->bi_end_io = request_endio; |
843 | miss->bi_private = &s->cl; | |
cafe5635 KO |
844 | closure_bio_submit(miss, &s->cl, s->d); |
845 | return ret; | |
846 | } | |
847 | ||
cdd972b1 | 848 | static void cached_dev_read(struct cached_dev *dc, struct search *s) |
cafe5635 KO |
849 | { |
850 | struct closure *cl = &s->cl; | |
851 | ||
220bb38c | 852 | closure_call(&s->iop.cl, cache_lookup, NULL, cl); |
cdd972b1 | 853 | continue_at(cl, cached_dev_read_done_bh, NULL); |
cafe5635 KO |
854 | } |
855 | ||
856 | /* Process writes */ | |
857 | ||
858 | static void cached_dev_write_complete(struct closure *cl) | |
859 | { | |
860 | struct search *s = container_of(cl, struct search, cl); | |
861 | struct cached_dev *dc = container_of(s->d, struct cached_dev, disk); | |
862 | ||
863 | up_read_non_owner(&dc->writeback_lock); | |
864 | cached_dev_bio_complete(cl); | |
865 | } | |
866 | ||
cdd972b1 | 867 | static void cached_dev_write(struct cached_dev *dc, struct search *s) |
cafe5635 KO |
868 | { |
869 | struct closure *cl = &s->cl; | |
870 | struct bio *bio = &s->bio.bio; | |
4f024f37 | 871 | struct bkey start = KEY(dc->disk.id, bio->bi_iter.bi_sector, 0); |
84f0db03 | 872 | struct bkey end = KEY(dc->disk.id, bio_end_sector(bio), 0); |
cafe5635 | 873 | |
220bb38c | 874 | bch_keybuf_check_overlapping(&s->iop.c->moving_gc_keys, &start, &end); |
cafe5635 | 875 | |
cafe5635 | 876 | down_read_non_owner(&dc->writeback_lock); |
cafe5635 | 877 | if (bch_keybuf_check_overlapping(&dc->writeback_keys, &start, &end)) { |
84f0db03 KO |
878 | /* |
879 | * We overlap with some dirty data undergoing background | |
880 | * writeback, force this write to writeback | |
881 | */ | |
220bb38c KO |
882 | s->iop.bypass = false; |
883 | s->iop.writeback = true; | |
cafe5635 KO |
884 | } |
885 | ||
84f0db03 KO |
886 | /* |
887 | * Discards aren't _required_ to do anything, so skipping if | |
888 | * check_overlapping returned true is ok | |
889 | * | |
890 | * But check_overlapping drops dirty keys for which io hasn't started, | |
891 | * so we still want to call it. | |
892 | */ | |
cafe5635 | 893 | if (bio->bi_rw & REQ_DISCARD) |
220bb38c | 894 | s->iop.bypass = true; |
cafe5635 | 895 | |
72c27061 KO |
896 | if (should_writeback(dc, s->orig_bio, |
897 | cache_mode(dc, bio), | |
220bb38c KO |
898 | s->iop.bypass)) { |
899 | s->iop.bypass = false; | |
900 | s->iop.writeback = true; | |
72c27061 KO |
901 | } |
902 | ||
220bb38c KO |
903 | if (s->iop.bypass) { |
904 | s->iop.bio = s->orig_bio; | |
905 | bio_get(s->iop.bio); | |
cafe5635 | 906 | |
84f0db03 KO |
907 | if (!(bio->bi_rw & REQ_DISCARD) || |
908 | blk_queue_discard(bdev_get_queue(dc->bdev))) | |
909 | closure_bio_submit(bio, cl, s->d); | |
220bb38c | 910 | } else if (s->iop.writeback) { |
279afbad | 911 | bch_writeback_add(dc); |
220bb38c | 912 | s->iop.bio = bio; |
e49c7c37 | 913 | |
c0f04d88 | 914 | if (bio->bi_rw & REQ_FLUSH) { |
e49c7c37 | 915 | /* Also need to send a flush to the backing device */ |
d4eddd42 | 916 | struct bio *flush = bio_alloc_bioset(GFP_NOIO, 0, |
c0f04d88 | 917 | dc->disk.bio_split); |
e49c7c37 | 918 | |
c0f04d88 KO |
919 | flush->bi_rw = WRITE_FLUSH; |
920 | flush->bi_bdev = bio->bi_bdev; | |
921 | flush->bi_end_io = request_endio; | |
922 | flush->bi_private = cl; | |
923 | ||
924 | closure_bio_submit(flush, cl, s->d); | |
e49c7c37 | 925 | } |
84f0db03 | 926 | } else { |
59d276fe | 927 | s->iop.bio = bio_clone_fast(bio, GFP_NOIO, dc->disk.bio_split); |
84f0db03 KO |
928 | |
929 | closure_bio_submit(bio, cl, s->d); | |
cafe5635 | 930 | } |
84f0db03 | 931 | |
220bb38c | 932 | closure_call(&s->iop.cl, bch_data_insert, NULL, cl); |
cafe5635 | 933 | continue_at(cl, cached_dev_write_complete, NULL); |
cafe5635 KO |
934 | } |
935 | ||
a34a8bfd | 936 | static void cached_dev_nodata(struct closure *cl) |
cafe5635 | 937 | { |
a34a8bfd | 938 | struct search *s = container_of(cl, struct search, cl); |
cafe5635 KO |
939 | struct bio *bio = &s->bio.bio; |
940 | ||
220bb38c KO |
941 | if (s->iop.flush_journal) |
942 | bch_journal_meta(s->iop.c, cl); | |
cafe5635 | 943 | |
84f0db03 | 944 | /* If it's a flush, we send the flush to the backing device too */ |
cafe5635 KO |
945 | closure_bio_submit(bio, cl, s->d); |
946 | ||
947 | continue_at(cl, cached_dev_bio_complete, NULL); | |
948 | } | |
949 | ||
950 | /* Cached devices - read & write stuff */ | |
951 | ||
cafe5635 KO |
952 | static void cached_dev_make_request(struct request_queue *q, struct bio *bio) |
953 | { | |
954 | struct search *s; | |
955 | struct bcache_device *d = bio->bi_bdev->bd_disk->private_data; | |
956 | struct cached_dev *dc = container_of(d, struct cached_dev, disk); | |
aae4933d | 957 | int rw = bio_data_dir(bio); |
cafe5635 | 958 | |
aae4933d | 959 | generic_start_io_acct(rw, bio_sectors(bio), &d->disk->part0); |
cafe5635 KO |
960 | |
961 | bio->bi_bdev = dc->bdev; | |
4f024f37 | 962 | bio->bi_iter.bi_sector += dc->sb.data_offset; |
cafe5635 KO |
963 | |
964 | if (cached_dev_get(dc)) { | |
965 | s = search_alloc(bio, d); | |
220bb38c | 966 | trace_bcache_request_start(s->d, bio); |
cafe5635 | 967 | |
4f024f37 | 968 | if (!bio->bi_iter.bi_size) { |
a34a8bfd KO |
969 | /* |
970 | * can't call bch_journal_meta from under | |
971 | * generic_make_request | |
972 | */ | |
973 | continue_at_nobarrier(&s->cl, | |
974 | cached_dev_nodata, | |
975 | bcache_wq); | |
976 | } else { | |
220bb38c | 977 | s->iop.bypass = check_should_bypass(dc, bio); |
84f0db03 KO |
978 | |
979 | if (rw) | |
cdd972b1 | 980 | cached_dev_write(dc, s); |
84f0db03 | 981 | else |
cdd972b1 | 982 | cached_dev_read(dc, s); |
84f0db03 | 983 | } |
cafe5635 KO |
984 | } else { |
985 | if ((bio->bi_rw & REQ_DISCARD) && | |
986 | !blk_queue_discard(bdev_get_queue(dc->bdev))) | |
987 | bio_endio(bio, 0); | |
988 | else | |
989 | bch_generic_make_request(bio, &d->bio_split_hook); | |
990 | } | |
991 | } | |
992 | ||
993 | static int cached_dev_ioctl(struct bcache_device *d, fmode_t mode, | |
994 | unsigned int cmd, unsigned long arg) | |
995 | { | |
996 | struct cached_dev *dc = container_of(d, struct cached_dev, disk); | |
997 | return __blkdev_driver_ioctl(dc->bdev, mode, cmd, arg); | |
998 | } | |
999 | ||
1000 | static int cached_dev_congested(void *data, int bits) | |
1001 | { | |
1002 | struct bcache_device *d = data; | |
1003 | struct cached_dev *dc = container_of(d, struct cached_dev, disk); | |
1004 | struct request_queue *q = bdev_get_queue(dc->bdev); | |
1005 | int ret = 0; | |
1006 | ||
1007 | if (bdi_congested(&q->backing_dev_info, bits)) | |
1008 | return 1; | |
1009 | ||
1010 | if (cached_dev_get(dc)) { | |
1011 | unsigned i; | |
1012 | struct cache *ca; | |
1013 | ||
1014 | for_each_cache(ca, d->c, i) { | |
1015 | q = bdev_get_queue(ca->bdev); | |
1016 | ret |= bdi_congested(&q->backing_dev_info, bits); | |
1017 | } | |
1018 | ||
1019 | cached_dev_put(dc); | |
1020 | } | |
1021 | ||
1022 | return ret; | |
1023 | } | |
1024 | ||
1025 | void bch_cached_dev_request_init(struct cached_dev *dc) | |
1026 | { | |
1027 | struct gendisk *g = dc->disk.disk; | |
1028 | ||
1029 | g->queue->make_request_fn = cached_dev_make_request; | |
1030 | g->queue->backing_dev_info.congested_fn = cached_dev_congested; | |
1031 | dc->disk.cache_miss = cached_dev_cache_miss; | |
1032 | dc->disk.ioctl = cached_dev_ioctl; | |
1033 | } | |
1034 | ||
1035 | /* Flash backed devices */ | |
1036 | ||
1037 | static int flash_dev_cache_miss(struct btree *b, struct search *s, | |
1038 | struct bio *bio, unsigned sectors) | |
1039 | { | |
1b4eaf3d | 1040 | unsigned bytes = min(sectors, bio_sectors(bio)) << 9; |
cafe5635 | 1041 | |
1b4eaf3d KO |
1042 | swap(bio->bi_iter.bi_size, bytes); |
1043 | zero_fill_bio(bio); | |
1044 | swap(bio->bi_iter.bi_size, bytes); | |
cafe5635 | 1045 | |
1b4eaf3d | 1046 | bio_advance(bio, bytes); |
8e51e414 | 1047 | |
4f024f37 | 1048 | if (!bio->bi_iter.bi_size) |
2c1953e2 | 1049 | return MAP_DONE; |
cafe5635 | 1050 | |
2c1953e2 | 1051 | return MAP_CONTINUE; |
cafe5635 KO |
1052 | } |
1053 | ||
a34a8bfd KO |
1054 | static void flash_dev_nodata(struct closure *cl) |
1055 | { | |
1056 | struct search *s = container_of(cl, struct search, cl); | |
1057 | ||
220bb38c KO |
1058 | if (s->iop.flush_journal) |
1059 | bch_journal_meta(s->iop.c, cl); | |
a34a8bfd KO |
1060 | |
1061 | continue_at(cl, search_free, NULL); | |
1062 | } | |
1063 | ||
cafe5635 KO |
1064 | static void flash_dev_make_request(struct request_queue *q, struct bio *bio) |
1065 | { | |
1066 | struct search *s; | |
1067 | struct closure *cl; | |
1068 | struct bcache_device *d = bio->bi_bdev->bd_disk->private_data; | |
aae4933d | 1069 | int rw = bio_data_dir(bio); |
cafe5635 | 1070 | |
aae4933d | 1071 | generic_start_io_acct(rw, bio_sectors(bio), &d->disk->part0); |
cafe5635 KO |
1072 | |
1073 | s = search_alloc(bio, d); | |
1074 | cl = &s->cl; | |
1075 | bio = &s->bio.bio; | |
1076 | ||
220bb38c | 1077 | trace_bcache_request_start(s->d, bio); |
cafe5635 | 1078 | |
4f024f37 | 1079 | if (!bio->bi_iter.bi_size) { |
a34a8bfd KO |
1080 | /* |
1081 | * can't call bch_journal_meta from under | |
1082 | * generic_make_request | |
1083 | */ | |
1084 | continue_at_nobarrier(&s->cl, | |
1085 | flash_dev_nodata, | |
1086 | bcache_wq); | |
84f0db03 | 1087 | } else if (rw) { |
220bb38c | 1088 | bch_keybuf_check_overlapping(&s->iop.c->moving_gc_keys, |
4f024f37 | 1089 | &KEY(d->id, bio->bi_iter.bi_sector, 0), |
8e51e414 | 1090 | &KEY(d->id, bio_end_sector(bio), 0)); |
cafe5635 | 1091 | |
220bb38c KO |
1092 | s->iop.bypass = (bio->bi_rw & REQ_DISCARD) != 0; |
1093 | s->iop.writeback = true; | |
1094 | s->iop.bio = bio; | |
cafe5635 | 1095 | |
220bb38c | 1096 | closure_call(&s->iop.cl, bch_data_insert, NULL, cl); |
cafe5635 | 1097 | } else { |
220bb38c | 1098 | closure_call(&s->iop.cl, cache_lookup, NULL, cl); |
cafe5635 KO |
1099 | } |
1100 | ||
1101 | continue_at(cl, search_free, NULL); | |
1102 | } | |
1103 | ||
1104 | static int flash_dev_ioctl(struct bcache_device *d, fmode_t mode, | |
1105 | unsigned int cmd, unsigned long arg) | |
1106 | { | |
1107 | return -ENOTTY; | |
1108 | } | |
1109 | ||
1110 | static int flash_dev_congested(void *data, int bits) | |
1111 | { | |
1112 | struct bcache_device *d = data; | |
1113 | struct request_queue *q; | |
1114 | struct cache *ca; | |
1115 | unsigned i; | |
1116 | int ret = 0; | |
1117 | ||
1118 | for_each_cache(ca, d->c, i) { | |
1119 | q = bdev_get_queue(ca->bdev); | |
1120 | ret |= bdi_congested(&q->backing_dev_info, bits); | |
1121 | } | |
1122 | ||
1123 | return ret; | |
1124 | } | |
1125 | ||
1126 | void bch_flash_dev_request_init(struct bcache_device *d) | |
1127 | { | |
1128 | struct gendisk *g = d->disk; | |
1129 | ||
1130 | g->queue->make_request_fn = flash_dev_make_request; | |
1131 | g->queue->backing_dev_info.congested_fn = flash_dev_congested; | |
1132 | d->cache_miss = flash_dev_cache_miss; | |
1133 | d->ioctl = flash_dev_ioctl; | |
1134 | } | |
1135 | ||
1136 | void bch_request_exit(void) | |
1137 | { | |
cafe5635 KO |
1138 | if (bch_search_cache) |
1139 | kmem_cache_destroy(bch_search_cache); | |
1140 | } | |
1141 | ||
1142 | int __init bch_request_init(void) | |
1143 | { | |
1144 | bch_search_cache = KMEM_CACHE(search, 0); | |
1145 | if (!bch_search_cache) | |
1146 | return -ENOMEM; | |
1147 | ||
cafe5635 KO |
1148 | return 0; |
1149 | } |