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Commit | Line | Data |
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b2441318 | 1 | // SPDX-License-Identifier: GPL-2.0 |
cafe5635 KO |
2 | /* |
3 | * Main bcache entry point - handle a read or a write request and decide what to | |
4 | * do with it; the make_request functions are called by the block layer. | |
5 | * | |
6 | * Copyright 2010, 2011 Kent Overstreet <kent.overstreet@gmail.com> | |
7 | * Copyright 2012 Google, Inc. | |
8 | */ | |
9 | ||
10 | #include "bcache.h" | |
11 | #include "btree.h" | |
12 | #include "debug.h" | |
13 | #include "request.h" | |
279afbad | 14 | #include "writeback.h" |
cafe5635 | 15 | |
cafe5635 KO |
16 | #include <linux/module.h> |
17 | #include <linux/hash.h> | |
18 | #include <linux/random.h> | |
66114cad | 19 | #include <linux/backing-dev.h> |
cafe5635 KO |
20 | |
21 | #include <trace/events/bcache.h> | |
22 | ||
23 | #define CUTOFF_CACHE_ADD 95 | |
24 | #define CUTOFF_CACHE_READA 90 | |
cafe5635 KO |
25 | |
26 | struct kmem_cache *bch_search_cache; | |
27 | ||
a34a8bfd KO |
28 | static void bch_data_insert_start(struct closure *); |
29 | ||
cafe5635 KO |
30 | static unsigned cache_mode(struct cached_dev *dc, struct bio *bio) |
31 | { | |
cafe5635 KO |
32 | return BDEV_CACHE_MODE(&dc->sb); |
33 | } | |
34 | ||
35 | static bool verify(struct cached_dev *dc, struct bio *bio) | |
36 | { | |
cafe5635 KO |
37 | return dc->verify; |
38 | } | |
39 | ||
40 | static void bio_csum(struct bio *bio, struct bkey *k) | |
41 | { | |
7988613b KO |
42 | struct bio_vec bv; |
43 | struct bvec_iter iter; | |
cafe5635 | 44 | uint64_t csum = 0; |
cafe5635 | 45 | |
7988613b KO |
46 | bio_for_each_segment(bv, bio, iter) { |
47 | void *d = kmap(bv.bv_page) + bv.bv_offset; | |
48 | csum = bch_crc64_update(csum, d, bv.bv_len); | |
49 | kunmap(bv.bv_page); | |
cafe5635 KO |
50 | } |
51 | ||
52 | k->ptr[KEY_PTRS(k)] = csum & (~0ULL >> 1); | |
53 | } | |
54 | ||
55 | /* Insert data into cache */ | |
56 | ||
a34a8bfd | 57 | static void bch_data_insert_keys(struct closure *cl) |
cafe5635 | 58 | { |
220bb38c | 59 | struct data_insert_op *op = container_of(cl, struct data_insert_op, cl); |
c18536a7 | 60 | atomic_t *journal_ref = NULL; |
220bb38c | 61 | struct bkey *replace_key = op->replace ? &op->replace_key : NULL; |
6054c6d4 | 62 | int ret; |
cafe5635 | 63 | |
a34a8bfd KO |
64 | /* |
65 | * If we're looping, might already be waiting on | |
66 | * another journal write - can't wait on more than one journal write at | |
67 | * a time | |
68 | * | |
69 | * XXX: this looks wrong | |
70 | */ | |
71 | #if 0 | |
72 | while (atomic_read(&s->cl.remaining) & CLOSURE_WAITING) | |
73 | closure_sync(&s->cl); | |
74 | #endif | |
cafe5635 | 75 | |
220bb38c KO |
76 | if (!op->replace) |
77 | journal_ref = bch_journal(op->c, &op->insert_keys, | |
78 | op->flush_journal ? cl : NULL); | |
cafe5635 | 79 | |
220bb38c | 80 | ret = bch_btree_insert(op->c, &op->insert_keys, |
6054c6d4 KO |
81 | journal_ref, replace_key); |
82 | if (ret == -ESRCH) { | |
220bb38c | 83 | op->replace_collision = true; |
6054c6d4 | 84 | } else if (ret) { |
4e4cbee9 | 85 | op->status = BLK_STS_RESOURCE; |
220bb38c | 86 | op->insert_data_done = true; |
a34a8bfd | 87 | } |
cafe5635 | 88 | |
c18536a7 KO |
89 | if (journal_ref) |
90 | atomic_dec_bug(journal_ref); | |
cafe5635 | 91 | |
77b5a084 | 92 | if (!op->insert_data_done) { |
da415a09 | 93 | continue_at(cl, bch_data_insert_start, op->wq); |
77b5a084 JA |
94 | return; |
95 | } | |
cafe5635 | 96 | |
220bb38c | 97 | bch_keylist_free(&op->insert_keys); |
a34a8bfd | 98 | closure_return(cl); |
cafe5635 KO |
99 | } |
100 | ||
085d2a3d KO |
101 | static int bch_keylist_realloc(struct keylist *l, unsigned u64s, |
102 | struct cache_set *c) | |
103 | { | |
104 | size_t oldsize = bch_keylist_nkeys(l); | |
105 | size_t newsize = oldsize + u64s; | |
106 | ||
107 | /* | |
108 | * The journalling code doesn't handle the case where the keys to insert | |
109 | * is bigger than an empty write: If we just return -ENOMEM here, | |
110 | * bio_insert() and bio_invalidate() will insert the keys created so far | |
111 | * and finish the rest when the keylist is empty. | |
112 | */ | |
113 | if (newsize * sizeof(uint64_t) > block_bytes(c) - sizeof(struct jset)) | |
114 | return -ENOMEM; | |
115 | ||
116 | return __bch_keylist_realloc(l, u64s); | |
117 | } | |
118 | ||
a34a8bfd KO |
119 | static void bch_data_invalidate(struct closure *cl) |
120 | { | |
220bb38c KO |
121 | struct data_insert_op *op = container_of(cl, struct data_insert_op, cl); |
122 | struct bio *bio = op->bio; | |
a34a8bfd KO |
123 | |
124 | pr_debug("invalidating %i sectors from %llu", | |
4f024f37 | 125 | bio_sectors(bio), (uint64_t) bio->bi_iter.bi_sector); |
a34a8bfd KO |
126 | |
127 | while (bio_sectors(bio)) { | |
81ab4190 KO |
128 | unsigned sectors = min(bio_sectors(bio), |
129 | 1U << (KEY_SIZE_BITS - 1)); | |
a34a8bfd | 130 | |
085d2a3d | 131 | if (bch_keylist_realloc(&op->insert_keys, 2, op->c)) |
a34a8bfd KO |
132 | goto out; |
133 | ||
4f024f37 KO |
134 | bio->bi_iter.bi_sector += sectors; |
135 | bio->bi_iter.bi_size -= sectors << 9; | |
a34a8bfd | 136 | |
220bb38c | 137 | bch_keylist_add(&op->insert_keys, |
4f024f37 | 138 | &KEY(op->inode, bio->bi_iter.bi_sector, sectors)); |
a34a8bfd KO |
139 | } |
140 | ||
220bb38c | 141 | op->insert_data_done = true; |
a34a8bfd KO |
142 | bio_put(bio); |
143 | out: | |
da415a09 | 144 | continue_at(cl, bch_data_insert_keys, op->wq); |
a34a8bfd KO |
145 | } |
146 | ||
147 | static void bch_data_insert_error(struct closure *cl) | |
cafe5635 | 148 | { |
220bb38c | 149 | struct data_insert_op *op = container_of(cl, struct data_insert_op, cl); |
cafe5635 KO |
150 | |
151 | /* | |
152 | * Our data write just errored, which means we've got a bunch of keys to | |
153 | * insert that point to data that wasn't succesfully written. | |
154 | * | |
155 | * We don't have to insert those keys but we still have to invalidate | |
156 | * that region of the cache - so, if we just strip off all the pointers | |
157 | * from the keys we'll accomplish just that. | |
158 | */ | |
159 | ||
220bb38c | 160 | struct bkey *src = op->insert_keys.keys, *dst = op->insert_keys.keys; |
cafe5635 | 161 | |
220bb38c | 162 | while (src != op->insert_keys.top) { |
cafe5635 KO |
163 | struct bkey *n = bkey_next(src); |
164 | ||
165 | SET_KEY_PTRS(src, 0); | |
c2f95ae2 | 166 | memmove(dst, src, bkey_bytes(src)); |
cafe5635 KO |
167 | |
168 | dst = bkey_next(dst); | |
169 | src = n; | |
170 | } | |
171 | ||
220bb38c | 172 | op->insert_keys.top = dst; |
cafe5635 | 173 | |
a34a8bfd | 174 | bch_data_insert_keys(cl); |
cafe5635 KO |
175 | } |
176 | ||
4246a0b6 | 177 | static void bch_data_insert_endio(struct bio *bio) |
cafe5635 KO |
178 | { |
179 | struct closure *cl = bio->bi_private; | |
220bb38c | 180 | struct data_insert_op *op = container_of(cl, struct data_insert_op, cl); |
cafe5635 | 181 | |
4e4cbee9 | 182 | if (bio->bi_status) { |
cafe5635 | 183 | /* TODO: We could try to recover from this. */ |
220bb38c | 184 | if (op->writeback) |
4e4cbee9 | 185 | op->status = bio->bi_status; |
220bb38c | 186 | else if (!op->replace) |
da415a09 | 187 | set_closure_fn(cl, bch_data_insert_error, op->wq); |
cafe5635 KO |
188 | else |
189 | set_closure_fn(cl, NULL, NULL); | |
190 | } | |
191 | ||
4e4cbee9 | 192 | bch_bbio_endio(op->c, bio, bio->bi_status, "writing data to cache"); |
cafe5635 KO |
193 | } |
194 | ||
a34a8bfd | 195 | static void bch_data_insert_start(struct closure *cl) |
cafe5635 | 196 | { |
220bb38c KO |
197 | struct data_insert_op *op = container_of(cl, struct data_insert_op, cl); |
198 | struct bio *bio = op->bio, *n; | |
cafe5635 | 199 | |
e3b4825b NS |
200 | if (op->bypass) |
201 | return bch_data_invalidate(cl); | |
202 | ||
69daf03a TJ |
203 | if (atomic_sub_return(bio_sectors(bio), &op->c->sectors_to_gc) < 0) |
204 | wake_up_gc(op->c); | |
205 | ||
54d12f2b | 206 | /* |
28a8f0d3 | 207 | * Journal writes are marked REQ_PREFLUSH; if the original write was a |
54d12f2b KO |
208 | * flush, it'll wait on the journal write. |
209 | */ | |
1eff9d32 | 210 | bio->bi_opf &= ~(REQ_PREFLUSH|REQ_FUA); |
54d12f2b | 211 | |
cafe5635 KO |
212 | do { |
213 | unsigned i; | |
214 | struct bkey *k; | |
220bb38c | 215 | struct bio_set *split = op->c->bio_split; |
cafe5635 KO |
216 | |
217 | /* 1 for the device pointer and 1 for the chksum */ | |
220bb38c | 218 | if (bch_keylist_realloc(&op->insert_keys, |
085d2a3d | 219 | 3 + (op->csum ? 1 : 0), |
77b5a084 | 220 | op->c)) { |
da415a09 | 221 | continue_at(cl, bch_data_insert_keys, op->wq); |
77b5a084 JA |
222 | return; |
223 | } | |
cafe5635 | 224 | |
220bb38c | 225 | k = op->insert_keys.top; |
cafe5635 | 226 | bkey_init(k); |
220bb38c | 227 | SET_KEY_INODE(k, op->inode); |
4f024f37 | 228 | SET_KEY_OFFSET(k, bio->bi_iter.bi_sector); |
cafe5635 | 229 | |
2599b53b KO |
230 | if (!bch_alloc_sectors(op->c, k, bio_sectors(bio), |
231 | op->write_point, op->write_prio, | |
232 | op->writeback)) | |
cafe5635 KO |
233 | goto err; |
234 | ||
20d0189b | 235 | n = bio_next_split(bio, KEY_SIZE(k), GFP_NOIO, split); |
cafe5635 | 236 | |
a34a8bfd | 237 | n->bi_end_io = bch_data_insert_endio; |
cafe5635 KO |
238 | n->bi_private = cl; |
239 | ||
220bb38c | 240 | if (op->writeback) { |
cafe5635 KO |
241 | SET_KEY_DIRTY(k, true); |
242 | ||
243 | for (i = 0; i < KEY_PTRS(k); i++) | |
220bb38c | 244 | SET_GC_MARK(PTR_BUCKET(op->c, k, i), |
cafe5635 KO |
245 | GC_MARK_DIRTY); |
246 | } | |
247 | ||
220bb38c | 248 | SET_KEY_CSUM(k, op->csum); |
cafe5635 KO |
249 | if (KEY_CSUM(k)) |
250 | bio_csum(n, k); | |
251 | ||
c37511b8 | 252 | trace_bcache_cache_insert(k); |
220bb38c | 253 | bch_keylist_push(&op->insert_keys); |
cafe5635 | 254 | |
ad0d9e76 | 255 | bio_set_op_attrs(n, REQ_OP_WRITE, 0); |
220bb38c | 256 | bch_submit_bbio(n, op->c, k, 0); |
cafe5635 KO |
257 | } while (n != bio); |
258 | ||
220bb38c | 259 | op->insert_data_done = true; |
da415a09 | 260 | continue_at(cl, bch_data_insert_keys, op->wq); |
77b5a084 | 261 | return; |
cafe5635 KO |
262 | err: |
263 | /* bch_alloc_sectors() blocks if s->writeback = true */ | |
220bb38c | 264 | BUG_ON(op->writeback); |
cafe5635 KO |
265 | |
266 | /* | |
267 | * But if it's not a writeback write we'd rather just bail out if | |
268 | * there aren't any buckets ready to write to - it might take awhile and | |
269 | * we might be starving btree writes for gc or something. | |
270 | */ | |
271 | ||
220bb38c | 272 | if (!op->replace) { |
cafe5635 KO |
273 | /* |
274 | * Writethrough write: We can't complete the write until we've | |
275 | * updated the index. But we don't want to delay the write while | |
276 | * we wait for buckets to be freed up, so just invalidate the | |
277 | * rest of the write. | |
278 | */ | |
220bb38c | 279 | op->bypass = true; |
a34a8bfd | 280 | return bch_data_invalidate(cl); |
cafe5635 KO |
281 | } else { |
282 | /* | |
283 | * From a cache miss, we can just insert the keys for the data | |
284 | * we have written or bail out if we didn't do anything. | |
285 | */ | |
220bb38c | 286 | op->insert_data_done = true; |
cafe5635 KO |
287 | bio_put(bio); |
288 | ||
220bb38c | 289 | if (!bch_keylist_empty(&op->insert_keys)) |
da415a09 | 290 | continue_at(cl, bch_data_insert_keys, op->wq); |
cafe5635 KO |
291 | else |
292 | closure_return(cl); | |
293 | } | |
294 | } | |
295 | ||
296 | /** | |
a34a8bfd | 297 | * bch_data_insert - stick some data in the cache |
cafe5635 KO |
298 | * |
299 | * This is the starting point for any data to end up in a cache device; it could | |
300 | * be from a normal write, or a writeback write, or a write to a flash only | |
301 | * volume - it's also used by the moving garbage collector to compact data in | |
302 | * mostly empty buckets. | |
303 | * | |
304 | * It first writes the data to the cache, creating a list of keys to be inserted | |
305 | * (if the data had to be fragmented there will be multiple keys); after the | |
306 | * data is written it calls bch_journal, and after the keys have been added to | |
307 | * the next journal write they're inserted into the btree. | |
308 | * | |
c18536a7 | 309 | * It inserts the data in s->cache_bio; bi_sector is used for the key offset, |
cafe5635 KO |
310 | * and op->inode is used for the key inode. |
311 | * | |
c18536a7 KO |
312 | * If s->bypass is true, instead of inserting the data it invalidates the |
313 | * region of the cache represented by s->cache_bio and op->inode. | |
cafe5635 | 314 | */ |
a34a8bfd | 315 | void bch_data_insert(struct closure *cl) |
cafe5635 | 316 | { |
220bb38c | 317 | struct data_insert_op *op = container_of(cl, struct data_insert_op, cl); |
cafe5635 | 318 | |
60ae81ee SP |
319 | trace_bcache_write(op->c, op->inode, op->bio, |
320 | op->writeback, op->bypass); | |
220bb38c KO |
321 | |
322 | bch_keylist_init(&op->insert_keys); | |
323 | bio_get(op->bio); | |
a34a8bfd | 324 | bch_data_insert_start(cl); |
cafe5635 KO |
325 | } |
326 | ||
220bb38c KO |
327 | /* Congested? */ |
328 | ||
329 | unsigned bch_get_congested(struct cache_set *c) | |
330 | { | |
331 | int i; | |
332 | long rand; | |
333 | ||
334 | if (!c->congested_read_threshold_us && | |
335 | !c->congested_write_threshold_us) | |
336 | return 0; | |
337 | ||
338 | i = (local_clock_us() - c->congested_last_us) / 1024; | |
339 | if (i < 0) | |
340 | return 0; | |
341 | ||
342 | i += atomic_read(&c->congested); | |
343 | if (i >= 0) | |
344 | return 0; | |
345 | ||
346 | i += CONGESTED_MAX; | |
347 | ||
348 | if (i > 0) | |
349 | i = fract_exp_two(i, 6); | |
350 | ||
351 | rand = get_random_int(); | |
352 | i -= bitmap_weight(&rand, BITS_PER_LONG); | |
353 | ||
354 | return i > 0 ? i : 1; | |
355 | } | |
356 | ||
357 | static void add_sequential(struct task_struct *t) | |
358 | { | |
359 | ewma_add(t->sequential_io_avg, | |
360 | t->sequential_io, 8, 0); | |
361 | ||
362 | t->sequential_io = 0; | |
363 | } | |
364 | ||
365 | static struct hlist_head *iohash(struct cached_dev *dc, uint64_t k) | |
366 | { | |
367 | return &dc->io_hash[hash_64(k, RECENT_IO_BITS)]; | |
368 | } | |
369 | ||
370 | static bool check_should_bypass(struct cached_dev *dc, struct bio *bio) | |
371 | { | |
372 | struct cache_set *c = dc->disk.c; | |
373 | unsigned mode = cache_mode(dc, bio); | |
374 | unsigned sectors, congested = bch_get_congested(c); | |
375 | struct task_struct *task = current; | |
8aee1220 | 376 | struct io *i; |
220bb38c | 377 | |
c4d951dd | 378 | if (test_bit(BCACHE_DEV_DETACHING, &dc->disk.flags) || |
220bb38c | 379 | c->gc_stats.in_use > CUTOFF_CACHE_ADD || |
ad0d9e76 | 380 | (bio_op(bio) == REQ_OP_DISCARD)) |
220bb38c KO |
381 | goto skip; |
382 | ||
383 | if (mode == CACHE_MODE_NONE || | |
384 | (mode == CACHE_MODE_WRITEAROUND && | |
c8d93247 | 385 | op_is_write(bio_op(bio)))) |
220bb38c KO |
386 | goto skip; |
387 | ||
4f024f37 | 388 | if (bio->bi_iter.bi_sector & (c->sb.block_size - 1) || |
220bb38c KO |
389 | bio_sectors(bio) & (c->sb.block_size - 1)) { |
390 | pr_debug("skipping unaligned io"); | |
391 | goto skip; | |
392 | } | |
393 | ||
5ceaaad7 KO |
394 | if (bypass_torture_test(dc)) { |
395 | if ((get_random_int() & 3) == 3) | |
396 | goto skip; | |
397 | else | |
398 | goto rescale; | |
399 | } | |
400 | ||
220bb38c KO |
401 | if (!congested && !dc->sequential_cutoff) |
402 | goto rescale; | |
403 | ||
8aee1220 | 404 | spin_lock(&dc->io_lock); |
220bb38c | 405 | |
4f024f37 KO |
406 | hlist_for_each_entry(i, iohash(dc, bio->bi_iter.bi_sector), hash) |
407 | if (i->last == bio->bi_iter.bi_sector && | |
8aee1220 KO |
408 | time_before(jiffies, i->jiffies)) |
409 | goto found; | |
220bb38c | 410 | |
8aee1220 | 411 | i = list_first_entry(&dc->io_lru, struct io, lru); |
220bb38c | 412 | |
8aee1220 KO |
413 | add_sequential(task); |
414 | i->sequential = 0; | |
220bb38c | 415 | found: |
4f024f37 KO |
416 | if (i->sequential + bio->bi_iter.bi_size > i->sequential) |
417 | i->sequential += bio->bi_iter.bi_size; | |
220bb38c | 418 | |
8aee1220 KO |
419 | i->last = bio_end_sector(bio); |
420 | i->jiffies = jiffies + msecs_to_jiffies(5000); | |
421 | task->sequential_io = i->sequential; | |
220bb38c | 422 | |
8aee1220 KO |
423 | hlist_del(&i->hash); |
424 | hlist_add_head(&i->hash, iohash(dc, i->last)); | |
425 | list_move_tail(&i->lru, &dc->io_lru); | |
220bb38c | 426 | |
8aee1220 | 427 | spin_unlock(&dc->io_lock); |
220bb38c KO |
428 | |
429 | sectors = max(task->sequential_io, | |
430 | task->sequential_io_avg) >> 9; | |
431 | ||
432 | if (dc->sequential_cutoff && | |
433 | sectors >= dc->sequential_cutoff >> 9) { | |
434 | trace_bcache_bypass_sequential(bio); | |
435 | goto skip; | |
436 | } | |
437 | ||
438 | if (congested && sectors >= congested) { | |
439 | trace_bcache_bypass_congested(bio); | |
440 | goto skip; | |
441 | } | |
442 | ||
443 | rescale: | |
444 | bch_rescale_priorities(c, bio_sectors(bio)); | |
445 | return false; | |
446 | skip: | |
447 | bch_mark_sectors_bypassed(c, dc, bio_sectors(bio)); | |
448 | return true; | |
449 | } | |
450 | ||
2c1953e2 | 451 | /* Cache lookup */ |
cafe5635 | 452 | |
220bb38c KO |
453 | struct search { |
454 | /* Stack frame for bio_complete */ | |
455 | struct closure cl; | |
456 | ||
220bb38c KO |
457 | struct bbio bio; |
458 | struct bio *orig_bio; | |
459 | struct bio *cache_miss; | |
a5ae4300 | 460 | struct bcache_device *d; |
220bb38c KO |
461 | |
462 | unsigned insert_bio_sectors; | |
220bb38c | 463 | unsigned recoverable:1; |
220bb38c | 464 | unsigned write:1; |
5ceaaad7 | 465 | unsigned read_dirty_data:1; |
220bb38c KO |
466 | |
467 | unsigned long start_time; | |
468 | ||
469 | struct btree_op op; | |
470 | struct data_insert_op iop; | |
471 | }; | |
472 | ||
4246a0b6 | 473 | static void bch_cache_read_endio(struct bio *bio) |
cafe5635 KO |
474 | { |
475 | struct bbio *b = container_of(bio, struct bbio, bio); | |
476 | struct closure *cl = bio->bi_private; | |
477 | struct search *s = container_of(cl, struct search, cl); | |
478 | ||
479 | /* | |
480 | * If the bucket was reused while our bio was in flight, we might have | |
481 | * read the wrong data. Set s->error but not error so it doesn't get | |
482 | * counted against the cache device, but we'll still reread the data | |
483 | * from the backing device. | |
484 | */ | |
485 | ||
4e4cbee9 CH |
486 | if (bio->bi_status) |
487 | s->iop.status = bio->bi_status; | |
d56d000a KO |
488 | else if (!KEY_DIRTY(&b->key) && |
489 | ptr_stale(s->iop.c, &b->key, 0)) { | |
220bb38c | 490 | atomic_long_inc(&s->iop.c->cache_read_races); |
4e4cbee9 | 491 | s->iop.status = BLK_STS_IOERR; |
cafe5635 KO |
492 | } |
493 | ||
4e4cbee9 | 494 | bch_bbio_endio(s->iop.c, bio, bio->bi_status, "reading from cache"); |
cafe5635 KO |
495 | } |
496 | ||
2c1953e2 KO |
497 | /* |
498 | * Read from a single key, handling the initial cache miss if the key starts in | |
499 | * the middle of the bio | |
500 | */ | |
cc231966 | 501 | static int cache_lookup_fn(struct btree_op *op, struct btree *b, struct bkey *k) |
2c1953e2 KO |
502 | { |
503 | struct search *s = container_of(op, struct search, op); | |
cc231966 KO |
504 | struct bio *n, *bio = &s->bio.bio; |
505 | struct bkey *bio_key; | |
2c1953e2 | 506 | unsigned ptr; |
2c1953e2 | 507 | |
4f024f37 | 508 | if (bkey_cmp(k, &KEY(s->iop.inode, bio->bi_iter.bi_sector, 0)) <= 0) |
cc231966 KO |
509 | return MAP_CONTINUE; |
510 | ||
220bb38c | 511 | if (KEY_INODE(k) != s->iop.inode || |
4f024f37 | 512 | KEY_START(k) > bio->bi_iter.bi_sector) { |
cc231966 | 513 | unsigned bio_sectors = bio_sectors(bio); |
220bb38c | 514 | unsigned sectors = KEY_INODE(k) == s->iop.inode |
cc231966 | 515 | ? min_t(uint64_t, INT_MAX, |
4f024f37 | 516 | KEY_START(k) - bio->bi_iter.bi_sector) |
cc231966 KO |
517 | : INT_MAX; |
518 | ||
519 | int ret = s->d->cache_miss(b, s, bio, sectors); | |
520 | if (ret != MAP_CONTINUE) | |
521 | return ret; | |
522 | ||
523 | /* if this was a complete miss we shouldn't get here */ | |
524 | BUG_ON(bio_sectors <= sectors); | |
525 | } | |
526 | ||
527 | if (!KEY_SIZE(k)) | |
528 | return MAP_CONTINUE; | |
2c1953e2 KO |
529 | |
530 | /* XXX: figure out best pointer - for multiple cache devices */ | |
531 | ptr = 0; | |
532 | ||
533 | PTR_BUCKET(b->c, k, ptr)->prio = INITIAL_PRIO; | |
534 | ||
5ceaaad7 KO |
535 | if (KEY_DIRTY(k)) |
536 | s->read_dirty_data = true; | |
537 | ||
20d0189b KO |
538 | n = bio_next_split(bio, min_t(uint64_t, INT_MAX, |
539 | KEY_OFFSET(k) - bio->bi_iter.bi_sector), | |
540 | GFP_NOIO, s->d->bio_split); | |
2c1953e2 | 541 | |
cc231966 KO |
542 | bio_key = &container_of(n, struct bbio, bio)->key; |
543 | bch_bkey_copy_single_ptr(bio_key, k, ptr); | |
2c1953e2 | 544 | |
4f024f37 | 545 | bch_cut_front(&KEY(s->iop.inode, n->bi_iter.bi_sector, 0), bio_key); |
220bb38c | 546 | bch_cut_back(&KEY(s->iop.inode, bio_end_sector(n), 0), bio_key); |
2c1953e2 | 547 | |
cc231966 KO |
548 | n->bi_end_io = bch_cache_read_endio; |
549 | n->bi_private = &s->cl; | |
2c1953e2 | 550 | |
cc231966 KO |
551 | /* |
552 | * The bucket we're reading from might be reused while our bio | |
553 | * is in flight, and we could then end up reading the wrong | |
554 | * data. | |
555 | * | |
556 | * We guard against this by checking (in cache_read_endio()) if | |
557 | * the pointer is stale again; if so, we treat it as an error | |
558 | * and reread from the backing device (but we don't pass that | |
559 | * error up anywhere). | |
560 | */ | |
2c1953e2 | 561 | |
cc231966 KO |
562 | __bch_submit_bbio(n, b->c); |
563 | return n == bio ? MAP_DONE : MAP_CONTINUE; | |
2c1953e2 KO |
564 | } |
565 | ||
566 | static void cache_lookup(struct closure *cl) | |
567 | { | |
220bb38c | 568 | struct search *s = container_of(cl, struct search, iop.cl); |
2c1953e2 | 569 | struct bio *bio = &s->bio.bio; |
a5ae4300 | 570 | int ret; |
2c1953e2 | 571 | |
a5ae4300 | 572 | bch_btree_op_init(&s->op, -1); |
2c1953e2 | 573 | |
a5ae4300 KO |
574 | ret = bch_btree_map_keys(&s->op, s->iop.c, |
575 | &KEY(s->iop.inode, bio->bi_iter.bi_sector, 0), | |
576 | cache_lookup_fn, MAP_END_KEY); | |
77b5a084 | 577 | if (ret == -EAGAIN) { |
2c1953e2 | 578 | continue_at(cl, cache_lookup, bcache_wq); |
77b5a084 JA |
579 | return; |
580 | } | |
2c1953e2 KO |
581 | |
582 | closure_return(cl); | |
583 | } | |
584 | ||
585 | /* Common code for the make_request functions */ | |
586 | ||
4246a0b6 | 587 | static void request_endio(struct bio *bio) |
2c1953e2 KO |
588 | { |
589 | struct closure *cl = bio->bi_private; | |
590 | ||
4e4cbee9 | 591 | if (bio->bi_status) { |
2c1953e2 | 592 | struct search *s = container_of(cl, struct search, cl); |
4e4cbee9 | 593 | s->iop.status = bio->bi_status; |
2c1953e2 KO |
594 | /* Only cache read errors are recoverable */ |
595 | s->recoverable = false; | |
596 | } | |
597 | ||
598 | bio_put(bio); | |
599 | closure_put(cl); | |
600 | } | |
601 | ||
cafe5635 KO |
602 | static void bio_complete(struct search *s) |
603 | { | |
604 | if (s->orig_bio) { | |
74d46992 | 605 | struct request_queue *q = s->orig_bio->bi_disk->queue; |
d62e26b3 | 606 | generic_end_io_acct(q, bio_data_dir(s->orig_bio), |
aae4933d | 607 | &s->d->disk->part0, s->start_time); |
cafe5635 | 608 | |
220bb38c | 609 | trace_bcache_request_end(s->d, s->orig_bio); |
4e4cbee9 | 610 | s->orig_bio->bi_status = s->iop.status; |
4246a0b6 | 611 | bio_endio(s->orig_bio); |
cafe5635 KO |
612 | s->orig_bio = NULL; |
613 | } | |
614 | } | |
615 | ||
a5ae4300 | 616 | static void do_bio_hook(struct search *s, struct bio *orig_bio) |
cafe5635 KO |
617 | { |
618 | struct bio *bio = &s->bio.bio; | |
cafe5635 | 619 | |
3a83f467 | 620 | bio_init(bio, NULL, 0); |
a5ae4300 | 621 | __bio_clone_fast(bio, orig_bio); |
cafe5635 KO |
622 | bio->bi_end_io = request_endio; |
623 | bio->bi_private = &s->cl; | |
ed9c47be | 624 | |
dac56212 | 625 | bio_cnt_set(bio, 3); |
cafe5635 KO |
626 | } |
627 | ||
628 | static void search_free(struct closure *cl) | |
629 | { | |
630 | struct search *s = container_of(cl, struct search, cl); | |
631 | bio_complete(s); | |
632 | ||
220bb38c KO |
633 | if (s->iop.bio) |
634 | bio_put(s->iop.bio); | |
cafe5635 | 635 | |
cafe5635 KO |
636 | closure_debug_destroy(cl); |
637 | mempool_free(s, s->d->c->search); | |
638 | } | |
639 | ||
a5ae4300 KO |
640 | static inline struct search *search_alloc(struct bio *bio, |
641 | struct bcache_device *d) | |
cafe5635 | 642 | { |
0b93207a | 643 | struct search *s; |
0b93207a KO |
644 | |
645 | s = mempool_alloc(d->c->search, GFP_NOIO); | |
cafe5635 | 646 | |
a5ae4300 KO |
647 | closure_init(&s->cl, NULL); |
648 | do_bio_hook(s, bio); | |
cafe5635 | 649 | |
cafe5635 | 650 | s->orig_bio = bio; |
a5ae4300 KO |
651 | s->cache_miss = NULL; |
652 | s->d = d; | |
cafe5635 | 653 | s->recoverable = 1; |
c8d93247 | 654 | s->write = op_is_write(bio_op(bio)); |
a5ae4300 | 655 | s->read_dirty_data = 0; |
cafe5635 | 656 | s->start_time = jiffies; |
a5ae4300 KO |
657 | |
658 | s->iop.c = d->c; | |
659 | s->iop.bio = NULL; | |
660 | s->iop.inode = d->id; | |
661 | s->iop.write_point = hash_long((unsigned long) current, 16); | |
662 | s->iop.write_prio = 0; | |
4e4cbee9 | 663 | s->iop.status = 0; |
a5ae4300 | 664 | s->iop.flags = 0; |
f73f44eb | 665 | s->iop.flush_journal = op_is_flush(bio->bi_opf); |
da415a09 | 666 | s->iop.wq = bcache_wq; |
cafe5635 | 667 | |
cafe5635 KO |
668 | return s; |
669 | } | |
670 | ||
cafe5635 KO |
671 | /* Cached devices */ |
672 | ||
673 | static void cached_dev_bio_complete(struct closure *cl) | |
674 | { | |
675 | struct search *s = container_of(cl, struct search, cl); | |
676 | struct cached_dev *dc = container_of(s->d, struct cached_dev, disk); | |
677 | ||
678 | search_free(cl); | |
679 | cached_dev_put(dc); | |
680 | } | |
681 | ||
682 | /* Process reads */ | |
683 | ||
cdd972b1 | 684 | static void cached_dev_cache_miss_done(struct closure *cl) |
cafe5635 KO |
685 | { |
686 | struct search *s = container_of(cl, struct search, cl); | |
687 | ||
220bb38c KO |
688 | if (s->iop.replace_collision) |
689 | bch_mark_cache_miss_collision(s->iop.c, s->d); | |
cafe5635 | 690 | |
491221f8 GJ |
691 | if (s->iop.bio) |
692 | bio_free_pages(s->iop.bio); | |
cafe5635 KO |
693 | |
694 | cached_dev_bio_complete(cl); | |
695 | } | |
696 | ||
cdd972b1 | 697 | static void cached_dev_read_error(struct closure *cl) |
cafe5635 KO |
698 | { |
699 | struct search *s = container_of(cl, struct search, cl); | |
cdd972b1 | 700 | struct bio *bio = &s->bio.bio; |
cafe5635 KO |
701 | |
702 | if (s->recoverable) { | |
c37511b8 KO |
703 | /* Retry from the backing device: */ |
704 | trace_bcache_read_retry(s->orig_bio); | |
cafe5635 | 705 | |
4e4cbee9 | 706 | s->iop.status = 0; |
a5ae4300 | 707 | do_bio_hook(s, s->orig_bio); |
cafe5635 KO |
708 | |
709 | /* XXX: invalidate cache */ | |
710 | ||
749b61da | 711 | closure_bio_submit(bio, cl); |
cafe5635 KO |
712 | } |
713 | ||
cdd972b1 | 714 | continue_at(cl, cached_dev_cache_miss_done, NULL); |
cafe5635 KO |
715 | } |
716 | ||
cdd972b1 | 717 | static void cached_dev_read_done(struct closure *cl) |
cafe5635 KO |
718 | { |
719 | struct search *s = container_of(cl, struct search, cl); | |
720 | struct cached_dev *dc = container_of(s->d, struct cached_dev, disk); | |
721 | ||
722 | /* | |
cdd972b1 KO |
723 | * We had a cache miss; cache_bio now contains data ready to be inserted |
724 | * into the cache. | |
cafe5635 KO |
725 | * |
726 | * First, we copy the data we just read from cache_bio's bounce buffers | |
727 | * to the buffers the original bio pointed to: | |
728 | */ | |
729 | ||
220bb38c KO |
730 | if (s->iop.bio) { |
731 | bio_reset(s->iop.bio); | |
4f024f37 | 732 | s->iop.bio->bi_iter.bi_sector = s->cache_miss->bi_iter.bi_sector; |
74d46992 | 733 | bio_copy_dev(s->iop.bio, s->cache_miss); |
4f024f37 | 734 | s->iop.bio->bi_iter.bi_size = s->insert_bio_sectors << 9; |
220bb38c | 735 | bch_bio_map(s->iop.bio, NULL); |
cafe5635 | 736 | |
220bb38c | 737 | bio_copy_data(s->cache_miss, s->iop.bio); |
cafe5635 KO |
738 | |
739 | bio_put(s->cache_miss); | |
740 | s->cache_miss = NULL; | |
741 | } | |
742 | ||
ed9c47be | 743 | if (verify(dc, &s->bio.bio) && s->recoverable && !s->read_dirty_data) |
220bb38c | 744 | bch_data_verify(dc, s->orig_bio); |
cafe5635 KO |
745 | |
746 | bio_complete(s); | |
747 | ||
220bb38c KO |
748 | if (s->iop.bio && |
749 | !test_bit(CACHE_SET_STOPPING, &s->iop.c->flags)) { | |
750 | BUG_ON(!s->iop.replace); | |
751 | closure_call(&s->iop.cl, bch_data_insert, NULL, cl); | |
cafe5635 KO |
752 | } |
753 | ||
cdd972b1 | 754 | continue_at(cl, cached_dev_cache_miss_done, NULL); |
cafe5635 KO |
755 | } |
756 | ||
cdd972b1 | 757 | static void cached_dev_read_done_bh(struct closure *cl) |
cafe5635 KO |
758 | { |
759 | struct search *s = container_of(cl, struct search, cl); | |
760 | struct cached_dev *dc = container_of(s->d, struct cached_dev, disk); | |
761 | ||
220bb38c KO |
762 | bch_mark_cache_accounting(s->iop.c, s->d, |
763 | !s->cache_miss, s->iop.bypass); | |
764 | trace_bcache_read(s->orig_bio, !s->cache_miss, s->iop.bypass); | |
cafe5635 | 765 | |
4e4cbee9 | 766 | if (s->iop.status) |
cdd972b1 | 767 | continue_at_nobarrier(cl, cached_dev_read_error, bcache_wq); |
220bb38c | 768 | else if (s->iop.bio || verify(dc, &s->bio.bio)) |
cdd972b1 | 769 | continue_at_nobarrier(cl, cached_dev_read_done, bcache_wq); |
cafe5635 | 770 | else |
cdd972b1 | 771 | continue_at_nobarrier(cl, cached_dev_bio_complete, NULL); |
cafe5635 KO |
772 | } |
773 | ||
774 | static int cached_dev_cache_miss(struct btree *b, struct search *s, | |
775 | struct bio *bio, unsigned sectors) | |
776 | { | |
2c1953e2 | 777 | int ret = MAP_CONTINUE; |
e7c590eb | 778 | unsigned reada = 0; |
cafe5635 | 779 | struct cached_dev *dc = container_of(s->d, struct cached_dev, disk); |
cdd972b1 | 780 | struct bio *miss, *cache_bio; |
cafe5635 | 781 | |
220bb38c | 782 | if (s->cache_miss || s->iop.bypass) { |
20d0189b | 783 | miss = bio_next_split(bio, sectors, GFP_NOIO, s->d->bio_split); |
2c1953e2 | 784 | ret = miss == bio ? MAP_DONE : MAP_CONTINUE; |
e7c590eb KO |
785 | goto out_submit; |
786 | } | |
cafe5635 | 787 | |
1eff9d32 JA |
788 | if (!(bio->bi_opf & REQ_RAHEAD) && |
789 | !(bio->bi_opf & REQ_META) && | |
220bb38c | 790 | s->iop.c->gc_stats.in_use < CUTOFF_CACHE_READA) |
e7c590eb | 791 | reada = min_t(sector_t, dc->readahead >> 9, |
74d46992 | 792 | get_capacity(bio->bi_disk) - bio_end_sector(bio)); |
cafe5635 | 793 | |
220bb38c | 794 | s->insert_bio_sectors = min(sectors, bio_sectors(bio) + reada); |
cafe5635 | 795 | |
220bb38c | 796 | s->iop.replace_key = KEY(s->iop.inode, |
4f024f37 | 797 | bio->bi_iter.bi_sector + s->insert_bio_sectors, |
220bb38c | 798 | s->insert_bio_sectors); |
e7c590eb | 799 | |
220bb38c | 800 | ret = bch_btree_insert_check_key(b, &s->op, &s->iop.replace_key); |
e7c590eb KO |
801 | if (ret) |
802 | return ret; | |
803 | ||
220bb38c | 804 | s->iop.replace = true; |
1b207d80 | 805 | |
20d0189b | 806 | miss = bio_next_split(bio, sectors, GFP_NOIO, s->d->bio_split); |
2c1953e2 KO |
807 | |
808 | /* btree_search_recurse()'s btree iterator is no good anymore */ | |
809 | ret = miss == bio ? MAP_DONE : -EINTR; | |
cafe5635 | 810 | |
cdd972b1 | 811 | cache_bio = bio_alloc_bioset(GFP_NOWAIT, |
220bb38c | 812 | DIV_ROUND_UP(s->insert_bio_sectors, PAGE_SECTORS), |
cafe5635 | 813 | dc->disk.bio_split); |
cdd972b1 | 814 | if (!cache_bio) |
cafe5635 KO |
815 | goto out_submit; |
816 | ||
4f024f37 | 817 | cache_bio->bi_iter.bi_sector = miss->bi_iter.bi_sector; |
74d46992 | 818 | bio_copy_dev(cache_bio, miss); |
4f024f37 | 819 | cache_bio->bi_iter.bi_size = s->insert_bio_sectors << 9; |
cafe5635 | 820 | |
cdd972b1 KO |
821 | cache_bio->bi_end_io = request_endio; |
822 | cache_bio->bi_private = &s->cl; | |
cafe5635 | 823 | |
cdd972b1 KO |
824 | bch_bio_map(cache_bio, NULL); |
825 | if (bio_alloc_pages(cache_bio, __GFP_NOWARN|GFP_NOIO)) | |
cafe5635 KO |
826 | goto out_put; |
827 | ||
220bb38c KO |
828 | if (reada) |
829 | bch_mark_cache_readahead(s->iop.c, s->d); | |
830 | ||
cdd972b1 | 831 | s->cache_miss = miss; |
220bb38c | 832 | s->iop.bio = cache_bio; |
cdd972b1 | 833 | bio_get(cache_bio); |
749b61da | 834 | closure_bio_submit(cache_bio, &s->cl); |
cafe5635 KO |
835 | |
836 | return ret; | |
837 | out_put: | |
cdd972b1 | 838 | bio_put(cache_bio); |
cafe5635 | 839 | out_submit: |
e7c590eb KO |
840 | miss->bi_end_io = request_endio; |
841 | miss->bi_private = &s->cl; | |
749b61da | 842 | closure_bio_submit(miss, &s->cl); |
cafe5635 KO |
843 | return ret; |
844 | } | |
845 | ||
cdd972b1 | 846 | static void cached_dev_read(struct cached_dev *dc, struct search *s) |
cafe5635 KO |
847 | { |
848 | struct closure *cl = &s->cl; | |
849 | ||
220bb38c | 850 | closure_call(&s->iop.cl, cache_lookup, NULL, cl); |
cdd972b1 | 851 | continue_at(cl, cached_dev_read_done_bh, NULL); |
cafe5635 KO |
852 | } |
853 | ||
854 | /* Process writes */ | |
855 | ||
856 | static void cached_dev_write_complete(struct closure *cl) | |
857 | { | |
858 | struct search *s = container_of(cl, struct search, cl); | |
859 | struct cached_dev *dc = container_of(s->d, struct cached_dev, disk); | |
860 | ||
861 | up_read_non_owner(&dc->writeback_lock); | |
862 | cached_dev_bio_complete(cl); | |
863 | } | |
864 | ||
cdd972b1 | 865 | static void cached_dev_write(struct cached_dev *dc, struct search *s) |
cafe5635 KO |
866 | { |
867 | struct closure *cl = &s->cl; | |
868 | struct bio *bio = &s->bio.bio; | |
4f024f37 | 869 | struct bkey start = KEY(dc->disk.id, bio->bi_iter.bi_sector, 0); |
84f0db03 | 870 | struct bkey end = KEY(dc->disk.id, bio_end_sector(bio), 0); |
cafe5635 | 871 | |
220bb38c | 872 | bch_keybuf_check_overlapping(&s->iop.c->moving_gc_keys, &start, &end); |
cafe5635 | 873 | |
cafe5635 | 874 | down_read_non_owner(&dc->writeback_lock); |
cafe5635 | 875 | if (bch_keybuf_check_overlapping(&dc->writeback_keys, &start, &end)) { |
84f0db03 KO |
876 | /* |
877 | * We overlap with some dirty data undergoing background | |
878 | * writeback, force this write to writeback | |
879 | */ | |
220bb38c KO |
880 | s->iop.bypass = false; |
881 | s->iop.writeback = true; | |
cafe5635 KO |
882 | } |
883 | ||
84f0db03 KO |
884 | /* |
885 | * Discards aren't _required_ to do anything, so skipping if | |
886 | * check_overlapping returned true is ok | |
887 | * | |
888 | * But check_overlapping drops dirty keys for which io hasn't started, | |
889 | * so we still want to call it. | |
890 | */ | |
ad0d9e76 | 891 | if (bio_op(bio) == REQ_OP_DISCARD) |
220bb38c | 892 | s->iop.bypass = true; |
cafe5635 | 893 | |
72c27061 KO |
894 | if (should_writeback(dc, s->orig_bio, |
895 | cache_mode(dc, bio), | |
220bb38c KO |
896 | s->iop.bypass)) { |
897 | s->iop.bypass = false; | |
898 | s->iop.writeback = true; | |
72c27061 KO |
899 | } |
900 | ||
220bb38c KO |
901 | if (s->iop.bypass) { |
902 | s->iop.bio = s->orig_bio; | |
903 | bio_get(s->iop.bio); | |
cafe5635 | 904 | |
ad0d9e76 | 905 | if ((bio_op(bio) != REQ_OP_DISCARD) || |
84f0db03 | 906 | blk_queue_discard(bdev_get_queue(dc->bdev))) |
749b61da | 907 | closure_bio_submit(bio, cl); |
220bb38c | 908 | } else if (s->iop.writeback) { |
279afbad | 909 | bch_writeback_add(dc); |
220bb38c | 910 | s->iop.bio = bio; |
e49c7c37 | 911 | |
1eff9d32 | 912 | if (bio->bi_opf & REQ_PREFLUSH) { |
e49c7c37 | 913 | /* Also need to send a flush to the backing device */ |
d4eddd42 | 914 | struct bio *flush = bio_alloc_bioset(GFP_NOIO, 0, |
c0f04d88 | 915 | dc->disk.bio_split); |
e49c7c37 | 916 | |
74d46992 | 917 | bio_copy_dev(flush, bio); |
c0f04d88 KO |
918 | flush->bi_end_io = request_endio; |
919 | flush->bi_private = cl; | |
70fd7614 | 920 | flush->bi_opf = REQ_OP_WRITE | REQ_PREFLUSH; |
c0f04d88 | 921 | |
749b61da | 922 | closure_bio_submit(flush, cl); |
e49c7c37 | 923 | } |
84f0db03 | 924 | } else { |
59d276fe | 925 | s->iop.bio = bio_clone_fast(bio, GFP_NOIO, dc->disk.bio_split); |
84f0db03 | 926 | |
749b61da | 927 | closure_bio_submit(bio, cl); |
cafe5635 | 928 | } |
84f0db03 | 929 | |
220bb38c | 930 | closure_call(&s->iop.cl, bch_data_insert, NULL, cl); |
cafe5635 | 931 | continue_at(cl, cached_dev_write_complete, NULL); |
cafe5635 KO |
932 | } |
933 | ||
a34a8bfd | 934 | static void cached_dev_nodata(struct closure *cl) |
cafe5635 | 935 | { |
a34a8bfd | 936 | struct search *s = container_of(cl, struct search, cl); |
cafe5635 KO |
937 | struct bio *bio = &s->bio.bio; |
938 | ||
220bb38c KO |
939 | if (s->iop.flush_journal) |
940 | bch_journal_meta(s->iop.c, cl); | |
cafe5635 | 941 | |
84f0db03 | 942 | /* If it's a flush, we send the flush to the backing device too */ |
749b61da | 943 | closure_bio_submit(bio, cl); |
cafe5635 KO |
944 | |
945 | continue_at(cl, cached_dev_bio_complete, NULL); | |
946 | } | |
947 | ||
948 | /* Cached devices - read & write stuff */ | |
949 | ||
dece1635 JA |
950 | static blk_qc_t cached_dev_make_request(struct request_queue *q, |
951 | struct bio *bio) | |
cafe5635 KO |
952 | { |
953 | struct search *s; | |
74d46992 | 954 | struct bcache_device *d = bio->bi_disk->private_data; |
cafe5635 | 955 | struct cached_dev *dc = container_of(d, struct cached_dev, disk); |
aae4933d | 956 | int rw = bio_data_dir(bio); |
cafe5635 | 957 | |
d62e26b3 | 958 | generic_start_io_acct(q, rw, bio_sectors(bio), &d->disk->part0); |
cafe5635 | 959 | |
74d46992 | 960 | bio_set_dev(bio, dc->bdev); |
4f024f37 | 961 | bio->bi_iter.bi_sector += dc->sb.data_offset; |
cafe5635 KO |
962 | |
963 | if (cached_dev_get(dc)) { | |
964 | s = search_alloc(bio, d); | |
220bb38c | 965 | trace_bcache_request_start(s->d, bio); |
cafe5635 | 966 | |
4f024f37 | 967 | if (!bio->bi_iter.bi_size) { |
a34a8bfd KO |
968 | /* |
969 | * can't call bch_journal_meta from under | |
970 | * generic_make_request | |
971 | */ | |
972 | continue_at_nobarrier(&s->cl, | |
973 | cached_dev_nodata, | |
974 | bcache_wq); | |
975 | } else { | |
220bb38c | 976 | s->iop.bypass = check_should_bypass(dc, bio); |
84f0db03 KO |
977 | |
978 | if (rw) | |
cdd972b1 | 979 | cached_dev_write(dc, s); |
84f0db03 | 980 | else |
cdd972b1 | 981 | cached_dev_read(dc, s); |
84f0db03 | 982 | } |
cafe5635 | 983 | } else { |
ad0d9e76 | 984 | if ((bio_op(bio) == REQ_OP_DISCARD) && |
cafe5635 | 985 | !blk_queue_discard(bdev_get_queue(dc->bdev))) |
4246a0b6 | 986 | bio_endio(bio); |
cafe5635 | 987 | else |
749b61da | 988 | generic_make_request(bio); |
cafe5635 | 989 | } |
dece1635 JA |
990 | |
991 | return BLK_QC_T_NONE; | |
cafe5635 KO |
992 | } |
993 | ||
994 | static int cached_dev_ioctl(struct bcache_device *d, fmode_t mode, | |
995 | unsigned int cmd, unsigned long arg) | |
996 | { | |
997 | struct cached_dev *dc = container_of(d, struct cached_dev, disk); | |
998 | return __blkdev_driver_ioctl(dc->bdev, mode, cmd, arg); | |
999 | } | |
1000 | ||
1001 | static int cached_dev_congested(void *data, int bits) | |
1002 | { | |
1003 | struct bcache_device *d = data; | |
1004 | struct cached_dev *dc = container_of(d, struct cached_dev, disk); | |
1005 | struct request_queue *q = bdev_get_queue(dc->bdev); | |
1006 | int ret = 0; | |
1007 | ||
dc3b17cc | 1008 | if (bdi_congested(q->backing_dev_info, bits)) |
cafe5635 KO |
1009 | return 1; |
1010 | ||
1011 | if (cached_dev_get(dc)) { | |
1012 | unsigned i; | |
1013 | struct cache *ca; | |
1014 | ||
1015 | for_each_cache(ca, d->c, i) { | |
1016 | q = bdev_get_queue(ca->bdev); | |
dc3b17cc | 1017 | ret |= bdi_congested(q->backing_dev_info, bits); |
cafe5635 KO |
1018 | } |
1019 | ||
1020 | cached_dev_put(dc); | |
1021 | } | |
1022 | ||
1023 | return ret; | |
1024 | } | |
1025 | ||
1026 | void bch_cached_dev_request_init(struct cached_dev *dc) | |
1027 | { | |
1028 | struct gendisk *g = dc->disk.disk; | |
1029 | ||
1030 | g->queue->make_request_fn = cached_dev_make_request; | |
dc3b17cc | 1031 | g->queue->backing_dev_info->congested_fn = cached_dev_congested; |
cafe5635 KO |
1032 | dc->disk.cache_miss = cached_dev_cache_miss; |
1033 | dc->disk.ioctl = cached_dev_ioctl; | |
1034 | } | |
1035 | ||
1036 | /* Flash backed devices */ | |
1037 | ||
1038 | static int flash_dev_cache_miss(struct btree *b, struct search *s, | |
1039 | struct bio *bio, unsigned sectors) | |
1040 | { | |
1b4eaf3d | 1041 | unsigned bytes = min(sectors, bio_sectors(bio)) << 9; |
cafe5635 | 1042 | |
1b4eaf3d KO |
1043 | swap(bio->bi_iter.bi_size, bytes); |
1044 | zero_fill_bio(bio); | |
1045 | swap(bio->bi_iter.bi_size, bytes); | |
cafe5635 | 1046 | |
1b4eaf3d | 1047 | bio_advance(bio, bytes); |
8e51e414 | 1048 | |
4f024f37 | 1049 | if (!bio->bi_iter.bi_size) |
2c1953e2 | 1050 | return MAP_DONE; |
cafe5635 | 1051 | |
2c1953e2 | 1052 | return MAP_CONTINUE; |
cafe5635 KO |
1053 | } |
1054 | ||
a34a8bfd KO |
1055 | static void flash_dev_nodata(struct closure *cl) |
1056 | { | |
1057 | struct search *s = container_of(cl, struct search, cl); | |
1058 | ||
220bb38c KO |
1059 | if (s->iop.flush_journal) |
1060 | bch_journal_meta(s->iop.c, cl); | |
a34a8bfd KO |
1061 | |
1062 | continue_at(cl, search_free, NULL); | |
1063 | } | |
1064 | ||
dece1635 JA |
1065 | static blk_qc_t flash_dev_make_request(struct request_queue *q, |
1066 | struct bio *bio) | |
cafe5635 KO |
1067 | { |
1068 | struct search *s; | |
1069 | struct closure *cl; | |
74d46992 | 1070 | struct bcache_device *d = bio->bi_disk->private_data; |
aae4933d | 1071 | int rw = bio_data_dir(bio); |
cafe5635 | 1072 | |
d62e26b3 | 1073 | generic_start_io_acct(q, rw, bio_sectors(bio), &d->disk->part0); |
cafe5635 KO |
1074 | |
1075 | s = search_alloc(bio, d); | |
1076 | cl = &s->cl; | |
1077 | bio = &s->bio.bio; | |
1078 | ||
220bb38c | 1079 | trace_bcache_request_start(s->d, bio); |
cafe5635 | 1080 | |
4f024f37 | 1081 | if (!bio->bi_iter.bi_size) { |
a34a8bfd KO |
1082 | /* |
1083 | * can't call bch_journal_meta from under | |
1084 | * generic_make_request | |
1085 | */ | |
1086 | continue_at_nobarrier(&s->cl, | |
1087 | flash_dev_nodata, | |
1088 | bcache_wq); | |
dece1635 | 1089 | return BLK_QC_T_NONE; |
84f0db03 | 1090 | } else if (rw) { |
220bb38c | 1091 | bch_keybuf_check_overlapping(&s->iop.c->moving_gc_keys, |
4f024f37 | 1092 | &KEY(d->id, bio->bi_iter.bi_sector, 0), |
8e51e414 | 1093 | &KEY(d->id, bio_end_sector(bio), 0)); |
cafe5635 | 1094 | |
ad0d9e76 | 1095 | s->iop.bypass = (bio_op(bio) == REQ_OP_DISCARD) != 0; |
220bb38c KO |
1096 | s->iop.writeback = true; |
1097 | s->iop.bio = bio; | |
cafe5635 | 1098 | |
220bb38c | 1099 | closure_call(&s->iop.cl, bch_data_insert, NULL, cl); |
cafe5635 | 1100 | } else { |
220bb38c | 1101 | closure_call(&s->iop.cl, cache_lookup, NULL, cl); |
cafe5635 KO |
1102 | } |
1103 | ||
1104 | continue_at(cl, search_free, NULL); | |
dece1635 | 1105 | return BLK_QC_T_NONE; |
cafe5635 KO |
1106 | } |
1107 | ||
1108 | static int flash_dev_ioctl(struct bcache_device *d, fmode_t mode, | |
1109 | unsigned int cmd, unsigned long arg) | |
1110 | { | |
1111 | return -ENOTTY; | |
1112 | } | |
1113 | ||
1114 | static int flash_dev_congested(void *data, int bits) | |
1115 | { | |
1116 | struct bcache_device *d = data; | |
1117 | struct request_queue *q; | |
1118 | struct cache *ca; | |
1119 | unsigned i; | |
1120 | int ret = 0; | |
1121 | ||
1122 | for_each_cache(ca, d->c, i) { | |
1123 | q = bdev_get_queue(ca->bdev); | |
dc3b17cc | 1124 | ret |= bdi_congested(q->backing_dev_info, bits); |
cafe5635 KO |
1125 | } |
1126 | ||
1127 | return ret; | |
1128 | } | |
1129 | ||
1130 | void bch_flash_dev_request_init(struct bcache_device *d) | |
1131 | { | |
1132 | struct gendisk *g = d->disk; | |
1133 | ||
1134 | g->queue->make_request_fn = flash_dev_make_request; | |
dc3b17cc | 1135 | g->queue->backing_dev_info->congested_fn = flash_dev_congested; |
cafe5635 KO |
1136 | d->cache_miss = flash_dev_cache_miss; |
1137 | d->ioctl = flash_dev_ioctl; | |
1138 | } | |
1139 | ||
1140 | void bch_request_exit(void) | |
1141 | { | |
cafe5635 KO |
1142 | if (bch_search_cache) |
1143 | kmem_cache_destroy(bch_search_cache); | |
1144 | } | |
1145 | ||
1146 | int __init bch_request_init(void) | |
1147 | { | |
1148 | bch_search_cache = KMEM_CACHE(search, 0); | |
1149 | if (!bch_search_cache) | |
1150 | return -ENOMEM; | |
1151 | ||
cafe5635 KO |
1152 | return 0; |
1153 | } |