1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 2007 Oracle. All rights reserved.
4 * Copyright (C) 2022 Christoph Hellwig.
5 */
6
7#include <linux/bio.h>
8#include "bio.h"
9#include "ctree.h"
10#include "volumes.h"
11#include "raid56.h"
12#include "async-thread.h"
13#include "dev-replace.h"
14#include "rcu-string.h"
15#include "zoned.h"
16#include "file-item.h"
17#include "raid-stripe-tree.h"
18
19static struct bio_set btrfs_bioset;
20static struct bio_set btrfs_clone_bioset;
21static struct bio_set btrfs_repair_bioset;
22static mempool_t btrfs_failed_bio_pool;
23
24struct btrfs_failed_bio {
25 struct btrfs_bio *bbio;
26 int num_copies;
27 atomic_t repair_count;
28};
29
30/* Is this a data path I/O that needs storage layer checksum and repair? */
31static inline bool is_data_bbio(struct btrfs_bio *bbio)
32{
33 return bbio->inode && is_data_inode(inode: &bbio->inode->vfs_inode);
34}
35
36static bool bbio_has_ordered_extent(struct btrfs_bio *bbio)
37{
38 return is_data_bbio(bbio) && btrfs_op(bio: &bbio->bio) == BTRFS_MAP_WRITE;
39}
40
41/*
42 * Initialize a btrfs_bio structure. This skips the embedded bio itself as it
43 * is already initialized by the block layer.
44 */
45void btrfs_bio_init(struct btrfs_bio *bbio, struct btrfs_fs_info *fs_info,
46 btrfs_bio_end_io_t end_io, void *private)
47{
48 memset(bbio, 0, offsetof(struct btrfs_bio, bio));
49 bbio->fs_info = fs_info;
50 bbio->end_io = end_io;
51 bbio->private = private;
52 atomic_set(v: &bbio->pending_ios, i: 1);
53}
54
55/*
56 * Allocate a btrfs_bio structure. The btrfs_bio is the main I/O container for
57 * btrfs, and is used for all I/O submitted through btrfs_submit_bio.
58 *
59 * Just like the underlying bio_alloc_bioset it will not fail as it is backed by
60 * a mempool.
61 */
62struct btrfs_bio *btrfs_bio_alloc(unsigned int nr_vecs, blk_opf_t opf,
63 struct btrfs_fs_info *fs_info,
64 btrfs_bio_end_io_t end_io, void *private)
65{
66 struct btrfs_bio *bbio;
67 struct bio *bio;
68
69 bio = bio_alloc_bioset(NULL, nr_vecs, opf, GFP_NOFS, bs: &btrfs_bioset);
70 bbio = btrfs_bio(bio);
71 btrfs_bio_init(bbio, fs_info, end_io, private);
72 return bbio;
73}
74
75static struct btrfs_bio *btrfs_split_bio(struct btrfs_fs_info *fs_info,
76 struct btrfs_bio *orig_bbio,
77 u64 map_length, bool use_append)
78{
79 struct btrfs_bio *bbio;
80 struct bio *bio;
81
82 if (use_append) {
83 unsigned int nr_segs;
84
85 bio = bio_split_rw(bio: &orig_bbio->bio, lim: &fs_info->limits, segs: &nr_segs,
86 bs: &btrfs_clone_bioset, max_bytes: map_length);
87 } else {
88 bio = bio_split(bio: &orig_bbio->bio, sectors: map_length >> SECTOR_SHIFT,
89 GFP_NOFS, bs: &btrfs_clone_bioset);
90 }
91 bbio = btrfs_bio(bio);
92 btrfs_bio_init(bbio, fs_info, NULL, private: orig_bbio);
93 bbio->inode = orig_bbio->inode;
94 bbio->file_offset = orig_bbio->file_offset;
95 orig_bbio->file_offset += map_length;
96 if (bbio_has_ordered_extent(bbio)) {
97 refcount_inc(r: &orig_bbio->ordered->refs);
98 bbio->ordered = orig_bbio->ordered;
99 }
100 atomic_inc(v: &orig_bbio->pending_ios);
101 return bbio;
102}
103
104/* Free a bio that was never submitted to the underlying device. */
105static void btrfs_cleanup_bio(struct btrfs_bio *bbio)
106{
107 if (bbio_has_ordered_extent(bbio))
108 btrfs_put_ordered_extent(entry: bbio->ordered);
109 bio_put(&bbio->bio);
110}
111
112static void __btrfs_bio_end_io(struct btrfs_bio *bbio)
113{
114 if (bbio_has_ordered_extent(bbio)) {
115 struct btrfs_ordered_extent *ordered = bbio->ordered;
116
117 bbio->end_io(bbio);
118 btrfs_put_ordered_extent(entry: ordered);
119 } else {
120 bbio->end_io(bbio);
121 }
122}
123
124void btrfs_bio_end_io(struct btrfs_bio *bbio, blk_status_t status)
125{
126 bbio->bio.bi_status = status;
127 __btrfs_bio_end_io(bbio);
128}
129
130static void btrfs_orig_write_end_io(struct bio *bio);
131
132static void btrfs_bbio_propagate_error(struct btrfs_bio *bbio,
133 struct btrfs_bio *orig_bbio)
134{
135 /*
136 * For writes we tolerate nr_mirrors - 1 write failures, so we can't
137 * just blindly propagate a write failure here. Instead increment the
138 * error count in the original I/O context so that it is guaranteed to
139 * be larger than the error tolerance.
140 */
141 if (bbio->bio.bi_end_io == &btrfs_orig_write_end_io) {
142 struct btrfs_io_stripe *orig_stripe = orig_bbio->bio.bi_private;
143 struct btrfs_io_context *orig_bioc = orig_stripe->bioc;
144
145 atomic_add(i: orig_bioc->max_errors, v: &orig_bioc->error);
146 } else {
147 orig_bbio->bio.bi_status = bbio->bio.bi_status;
148 }
149}
150
151static void btrfs_orig_bbio_end_io(struct btrfs_bio *bbio)
152{
153 if (bbio->bio.bi_pool == &btrfs_clone_bioset) {
154 struct btrfs_bio *orig_bbio = bbio->private;
155
156 if (bbio->bio.bi_status)
157 btrfs_bbio_propagate_error(bbio, orig_bbio);
158 btrfs_cleanup_bio(bbio);
159 bbio = orig_bbio;
160 }
161
162 if (atomic_dec_and_test(v: &bbio->pending_ios))
163 __btrfs_bio_end_io(bbio);
164}
165
166static int next_repair_mirror(struct btrfs_failed_bio *fbio, int cur_mirror)
167{
168 if (cur_mirror == fbio->num_copies)
169 return cur_mirror + 1 - fbio->num_copies;
170 return cur_mirror + 1;
171}
172
173static int prev_repair_mirror(struct btrfs_failed_bio *fbio, int cur_mirror)
174{
175 if (cur_mirror == 1)
176 return fbio->num_copies;
177 return cur_mirror - 1;
178}
179
180static void btrfs_repair_done(struct btrfs_failed_bio *fbio)
181{
182 if (atomic_dec_and_test(v: &fbio->repair_count)) {
183 btrfs_orig_bbio_end_io(bbio: fbio->bbio);
184 mempool_free(element: fbio, pool: &btrfs_failed_bio_pool);
185 }
186}
187
188static void btrfs_end_repair_bio(struct btrfs_bio *repair_bbio,
189 struct btrfs_device *dev)
190{
191 struct btrfs_failed_bio *fbio = repair_bbio->private;
192 struct btrfs_inode *inode = repair_bbio->inode;
193 struct btrfs_fs_info *fs_info = inode->root->fs_info;
194 struct bio_vec *bv = bio_first_bvec_all(bio: &repair_bbio->bio);
195 int mirror = repair_bbio->mirror_num;
196
197 if (repair_bbio->bio.bi_status ||
198 !btrfs_data_csum_ok(bbio: repair_bbio, dev, bio_offset: 0, bv)) {
199 bio_reset(bio: &repair_bbio->bio, NULL, opf: REQ_OP_READ);
200 repair_bbio->bio.bi_iter = repair_bbio->saved_iter;
201
202 mirror = next_repair_mirror(fbio, cur_mirror: mirror);
203 if (mirror == fbio->bbio->mirror_num) {
204 btrfs_debug(fs_info, "no mirror left");
205 fbio->bbio->bio.bi_status = BLK_STS_IOERR;
206 goto done;
207 }
208
209 btrfs_submit_bio(bbio: repair_bbio, mirror_num: mirror);
210 return;
211 }
212
213 do {
214 mirror = prev_repair_mirror(fbio, cur_mirror: mirror);
215 btrfs_repair_io_failure(fs_info, ino: btrfs_ino(inode),
216 start: repair_bbio->file_offset, length: fs_info->sectorsize,
217 logical: repair_bbio->saved_iter.bi_sector << SECTOR_SHIFT,
218 page: bv->bv_page, pg_offset: bv->bv_offset, mirror_num: mirror);
219 } while (mirror != fbio->bbio->mirror_num);
220
221done:
222 btrfs_repair_done(fbio);
223 bio_put(&repair_bbio->bio);
224}
225
226/*
227 * Try to kick off a repair read to the next available mirror for a bad sector.
228 *
229 * This primarily tries to recover good data to serve the actual read request,
230 * but also tries to write the good data back to the bad mirror(s) when a
231 * read succeeded to restore the redundancy.
232 */
233static struct btrfs_failed_bio *repair_one_sector(struct btrfs_bio *failed_bbio,
234 u32 bio_offset,
235 struct bio_vec *bv,
236 struct btrfs_failed_bio *fbio)
237{
238 struct btrfs_inode *inode = failed_bbio->inode;
239 struct btrfs_fs_info *fs_info = inode->root->fs_info;
240 const u32 sectorsize = fs_info->sectorsize;
241 const u64 logical = (failed_bbio->saved_iter.bi_sector << SECTOR_SHIFT);
242 struct btrfs_bio *repair_bbio;
243 struct bio *repair_bio;
244 int num_copies;
245 int mirror;
246
247 btrfs_debug(fs_info, "repair read error: read error at %llu",
248 failed_bbio->file_offset + bio_offset);
249
250 num_copies = btrfs_num_copies(fs_info, logical, len: sectorsize);
251 if (num_copies == 1) {
252 btrfs_debug(fs_info, "no copy to repair from");
253 failed_bbio->bio.bi_status = BLK_STS_IOERR;
254 return fbio;
255 }
256
257 if (!fbio) {
258 fbio = mempool_alloc(pool: &btrfs_failed_bio_pool, GFP_NOFS);
259 fbio->bbio = failed_bbio;
260 fbio->num_copies = num_copies;
261 atomic_set(v: &fbio->repair_count, i: 1);
262 }
263
264 atomic_inc(v: &fbio->repair_count);
265
266 repair_bio = bio_alloc_bioset(NULL, nr_vecs: 1, opf: REQ_OP_READ, GFP_NOFS,
267 bs: &btrfs_repair_bioset);
268 repair_bio->bi_iter.bi_sector = failed_bbio->saved_iter.bi_sector;
269 __bio_add_page(bio: repair_bio, page: bv->bv_page, len: bv->bv_len, off: bv->bv_offset);
270
271 repair_bbio = btrfs_bio(bio: repair_bio);
272 btrfs_bio_init(bbio: repair_bbio, fs_info, NULL, private: fbio);
273 repair_bbio->inode = failed_bbio->inode;
274 repair_bbio->file_offset = failed_bbio->file_offset + bio_offset;
275
276 mirror = next_repair_mirror(fbio, cur_mirror: failed_bbio->mirror_num);
277 btrfs_debug(fs_info, "submitting repair read to mirror %d", mirror);
278 btrfs_submit_bio(bbio: repair_bbio, mirror_num: mirror);
279 return fbio;
280}
281
282static void btrfs_check_read_bio(struct btrfs_bio *bbio, struct btrfs_device *dev)
283{
284 struct btrfs_inode *inode = bbio->inode;
285 struct btrfs_fs_info *fs_info = inode->root->fs_info;
286 u32 sectorsize = fs_info->sectorsize;
287 struct bvec_iter *iter = &bbio->saved_iter;
288 blk_status_t status = bbio->bio.bi_status;
289 struct btrfs_failed_bio *fbio = NULL;
290 u32 offset = 0;
291
292 /* Read-repair requires the inode field to be set by the submitter. */
293 ASSERT(inode);
294
295 /*
296 * Hand off repair bios to the repair code as there is no upper level
297 * submitter for them.
298 */
299 if (bbio->bio.bi_pool == &btrfs_repair_bioset) {
300 btrfs_end_repair_bio(repair_bbio: bbio, dev);
301 return;
302 }
303
304 /* Clear the I/O error. A failed repair will reset it. */
305 bbio->bio.bi_status = BLK_STS_OK;
306
307 while (iter->bi_size) {
308 struct bio_vec bv = bio_iter_iovec(&bbio->bio, *iter);
309
310 bv.bv_len = min(bv.bv_len, sectorsize);
311 if (status || !btrfs_data_csum_ok(bbio, dev, bio_offset: offset, bv: &bv))
312 fbio = repair_one_sector(failed_bbio: bbio, bio_offset: offset, bv: &bv, fbio);
313
314 bio_advance_iter_single(bio: &bbio->bio, iter, bytes: sectorsize);
315 offset += sectorsize;
316 }
317
318 if (bbio->csum != bbio->csum_inline)
319 kfree(objp: bbio->csum);
320
321 if (fbio)
322 btrfs_repair_done(fbio);
323 else
324 btrfs_orig_bbio_end_io(bbio);
325}
326
327static void btrfs_log_dev_io_error(struct bio *bio, struct btrfs_device *dev)
328{
329 if (!dev || !dev->bdev)
330 return;
331 if (bio->bi_status != BLK_STS_IOERR && bio->bi_status != BLK_STS_TARGET)
332 return;
333
334 if (btrfs_op(bio) == BTRFS_MAP_WRITE)
335 btrfs_dev_stat_inc_and_print(dev, index: BTRFS_DEV_STAT_WRITE_ERRS);
336 else if (!(bio->bi_opf & REQ_RAHEAD))
337 btrfs_dev_stat_inc_and_print(dev, index: BTRFS_DEV_STAT_READ_ERRS);
338 if (bio->bi_opf & REQ_PREFLUSH)
339 btrfs_dev_stat_inc_and_print(dev, index: BTRFS_DEV_STAT_FLUSH_ERRS);
340}
341
342static struct workqueue_struct *btrfs_end_io_wq(struct btrfs_fs_info *fs_info,
343 struct bio *bio)
344{
345 if (bio->bi_opf & REQ_META)
346 return fs_info->endio_meta_workers;
347 return fs_info->endio_workers;
348}
349
350static void btrfs_end_bio_work(struct work_struct *work)
351{
352 struct btrfs_bio *bbio = container_of(work, struct btrfs_bio, end_io_work);
353
354 /* Metadata reads are checked and repaired by the submitter. */
355 if (is_data_bbio(bbio))
356 btrfs_check_read_bio(bbio, dev: bbio->bio.bi_private);
357 else
358 btrfs_orig_bbio_end_io(bbio);
359}
360
361static void btrfs_simple_end_io(struct bio *bio)
362{
363 struct btrfs_bio *bbio = btrfs_bio(bio);
364 struct btrfs_device *dev = bio->bi_private;
365 struct btrfs_fs_info *fs_info = bbio->fs_info;
366
367 btrfs_bio_counter_dec(fs_info);
368
369 if (bio->bi_status)
370 btrfs_log_dev_io_error(bio, dev);
371
372 if (bio_op(bio) == REQ_OP_READ) {
373 INIT_WORK(&bbio->end_io_work, btrfs_end_bio_work);
374 queue_work(wq: btrfs_end_io_wq(fs_info, bio), work: &bbio->end_io_work);
375 } else {
376 if (bio_op(bio) == REQ_OP_ZONE_APPEND && !bio->bi_status)
377 btrfs_record_physical_zoned(bbio);
378 btrfs_orig_bbio_end_io(bbio);
379 }
380}
381
382static void btrfs_raid56_end_io(struct bio *bio)
383{
384 struct btrfs_io_context *bioc = bio->bi_private;
385 struct btrfs_bio *bbio = btrfs_bio(bio);
386
387 btrfs_bio_counter_dec(fs_info: bioc->fs_info);
388 bbio->mirror_num = bioc->mirror_num;
389 if (bio_op(bio) == REQ_OP_READ && is_data_bbio(bbio))
390 btrfs_check_read_bio(bbio, NULL);
391 else
392 btrfs_orig_bbio_end_io(bbio);
393
394 btrfs_put_bioc(bioc);
395}
396
397static void btrfs_orig_write_end_io(struct bio *bio)
398{
399 struct btrfs_io_stripe *stripe = bio->bi_private;
400 struct btrfs_io_context *bioc = stripe->bioc;
401 struct btrfs_bio *bbio = btrfs_bio(bio);
402
403 btrfs_bio_counter_dec(fs_info: bioc->fs_info);
404
405 if (bio->bi_status) {
406 atomic_inc(v: &bioc->error);
407 btrfs_log_dev_io_error(bio, dev: stripe->dev);
408 }
409
410 /*
411 * Only send an error to the higher layers if it is beyond the tolerance
412 * threshold.
413 */
414 if (atomic_read(v: &bioc->error) > bioc->max_errors)
415 bio->bi_status = BLK_STS_IOERR;
416 else
417 bio->bi_status = BLK_STS_OK;
418
419 if (bio_op(bio) == REQ_OP_ZONE_APPEND && !bio->bi_status)
420 stripe->physical = bio->bi_iter.bi_sector << SECTOR_SHIFT;
421
422 btrfs_orig_bbio_end_io(bbio);
423 btrfs_put_bioc(bioc);
424}
425
426static void btrfs_clone_write_end_io(struct bio *bio)
427{
428 struct btrfs_io_stripe *stripe = bio->bi_private;
429
430 if (bio->bi_status) {
431 atomic_inc(v: &stripe->bioc->error);
432 btrfs_log_dev_io_error(bio, dev: stripe->dev);
433 } else if (bio_op(bio) == REQ_OP_ZONE_APPEND) {
434 stripe->physical = bio->bi_iter.bi_sector << SECTOR_SHIFT;
435 }
436
437 /* Pass on control to the original bio this one was cloned from */
438 bio_endio(stripe->bioc->orig_bio);
439 bio_put(bio);
440}
441
442static void btrfs_submit_dev_bio(struct btrfs_device *dev, struct bio *bio)
443{
444 if (!dev || !dev->bdev ||
445 test_bit(BTRFS_DEV_STATE_MISSING, &dev->dev_state) ||
446 (btrfs_op(bio) == BTRFS_MAP_WRITE &&
447 !test_bit(BTRFS_DEV_STATE_WRITEABLE, &dev->dev_state))) {
448 bio_io_error(bio);
449 return;
450 }
451
452 bio_set_dev(bio, bdev: dev->bdev);
453
454 /*
455 * For zone append writing, bi_sector must point the beginning of the
456 * zone
457 */
458 if (bio_op(bio) == REQ_OP_ZONE_APPEND) {
459 u64 physical = bio->bi_iter.bi_sector << SECTOR_SHIFT;
460 u64 zone_start = round_down(physical, dev->fs_info->zone_size);
461
462 ASSERT(btrfs_dev_is_sequential(dev, physical));
463 bio->bi_iter.bi_sector = zone_start >> SECTOR_SHIFT;
464 }
465 btrfs_debug_in_rcu(dev->fs_info,
466 "%s: rw %d 0x%x, sector=%llu, dev=%lu (%s id %llu), size=%u",
467 __func__, bio_op(bio), bio->bi_opf, bio->bi_iter.bi_sector,
468 (unsigned long)dev->bdev->bd_dev, btrfs_dev_name(dev),
469 dev->devid, bio->bi_iter.bi_size);
470
471 if (bio->bi_opf & REQ_BTRFS_CGROUP_PUNT)
472 blkcg_punt_bio_submit(bio);
473 else
474 submit_bio(bio);
475}
476
477static void btrfs_submit_mirrored_bio(struct btrfs_io_context *bioc, int dev_nr)
478{
479 struct bio *orig_bio = bioc->orig_bio, *bio;
480
481 ASSERT(bio_op(orig_bio) != REQ_OP_READ);
482
483 /* Reuse the bio embedded into the btrfs_bio for the last mirror */
484 if (dev_nr == bioc->num_stripes - 1) {
485 bio = orig_bio;
486 bio->bi_end_io = btrfs_orig_write_end_io;
487 } else {
488 bio = bio_alloc_clone(NULL, bio_src: orig_bio, GFP_NOFS, bs: &fs_bio_set);
489 bio_inc_remaining(bio: orig_bio);
490 bio->bi_end_io = btrfs_clone_write_end_io;
491 }
492
493 bio->bi_private = &bioc->stripes[dev_nr];
494 bio->bi_iter.bi_sector = bioc->stripes[dev_nr].physical >> SECTOR_SHIFT;
495 bioc->stripes[dev_nr].bioc = bioc;
496 bioc->size = bio->bi_iter.bi_size;
497 btrfs_submit_dev_bio(dev: bioc->stripes[dev_nr].dev, bio);
498}
499
500static void __btrfs_submit_bio(struct bio *bio, struct btrfs_io_context *bioc,
501 struct btrfs_io_stripe *smap, int mirror_num)
502{
503 if (!bioc) {
504 /* Single mirror read/write fast path. */
505 btrfs_bio(bio)->mirror_num = mirror_num;
506 if (bio_op(bio) != REQ_OP_READ)
507 btrfs_bio(bio)->orig_physical = smap->physical;
508 bio->bi_iter.bi_sector = smap->physical >> SECTOR_SHIFT;
509 if (bio_op(bio) != REQ_OP_READ)
510 btrfs_bio(bio)->orig_physical = smap->physical;
511 bio->bi_private = smap->dev;
512 bio->bi_end_io = btrfs_simple_end_io;
513 btrfs_submit_dev_bio(dev: smap->dev, bio);
514 } else if (bioc->map_type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
515 /* Parity RAID write or read recovery. */
516 bio->bi_private = bioc;
517 bio->bi_end_io = btrfs_raid56_end_io;
518 if (bio_op(bio) == REQ_OP_READ)
519 raid56_parity_recover(bio, bioc, mirror_num);
520 else
521 raid56_parity_write(bio, bioc);
522 } else {
523 /* Write to multiple mirrors. */
524 int total_devs = bioc->num_stripes;
525
526 bioc->orig_bio = bio;
527 for (int dev_nr = 0; dev_nr < total_devs; dev_nr++)
528 btrfs_submit_mirrored_bio(bioc, dev_nr);
529 }
530}
531
532static blk_status_t btrfs_bio_csum(struct btrfs_bio *bbio)
533{
534 if (bbio->bio.bi_opf & REQ_META)
535 return btree_csum_one_bio(bbio);
536 return btrfs_csum_one_bio(bbio);
537}
538
539/*
540 * Async submit bios are used to offload expensive checksumming onto the worker
541 * threads.
542 */
543struct async_submit_bio {
544 struct btrfs_bio *bbio;
545 struct btrfs_io_context *bioc;
546 struct btrfs_io_stripe smap;
547 int mirror_num;
548 struct btrfs_work work;
549};
550
551/*
552 * In order to insert checksums into the metadata in large chunks, we wait
553 * until bio submission time. All the pages in the bio are checksummed and
554 * sums are attached onto the ordered extent record.
555 *
556 * At IO completion time the csums attached on the ordered extent record are
557 * inserted into the btree.
558 */
559static void run_one_async_start(struct btrfs_work *work)
560{
561 struct async_submit_bio *async =
562 container_of(work, struct async_submit_bio, work);
563 blk_status_t ret;
564
565 ret = btrfs_bio_csum(bbio: async->bbio);
566 if (ret)
567 async->bbio->bio.bi_status = ret;
568}
569
570/*
571 * In order to insert checksums into the metadata in large chunks, we wait
572 * until bio submission time. All the pages in the bio are checksummed and
573 * sums are attached onto the ordered extent record.
574 *
575 * At IO completion time the csums attached on the ordered extent record are
576 * inserted into the tree.
577 *
578 * If called with @do_free == true, then it will free the work struct.
579 */
580static void run_one_async_done(struct btrfs_work *work, bool do_free)
581{
582 struct async_submit_bio *async =
583 container_of(work, struct async_submit_bio, work);
584 struct bio *bio = &async->bbio->bio;
585
586 if (do_free) {
587 kfree(container_of(work, struct async_submit_bio, work));
588 return;
589 }
590
591 /* If an error occurred we just want to clean up the bio and move on. */
592 if (bio->bi_status) {
593 btrfs_orig_bbio_end_io(bbio: async->bbio);
594 return;
595 }
596
597 /*
598 * All of the bios that pass through here are from async helpers.
599 * Use REQ_BTRFS_CGROUP_PUNT to issue them from the owning cgroup's
600 * context. This changes nothing when cgroups aren't in use.
601 */
602 bio->bi_opf |= REQ_BTRFS_CGROUP_PUNT;
603 __btrfs_submit_bio(bio, bioc: async->bioc, smap: &async->smap, mirror_num: async->mirror_num);
604}
605
606static bool should_async_write(struct btrfs_bio *bbio)
607{
608 /* Submit synchronously if the checksum implementation is fast. */
609 if (test_bit(BTRFS_FS_CSUM_IMPL_FAST, &bbio->fs_info->flags))
610 return false;
611
612 /*
613 * Try to defer the submission to a workqueue to parallelize the
614 * checksum calculation unless the I/O is issued synchronously.
615 */
616 if (op_is_sync(op: bbio->bio.bi_opf))
617 return false;
618
619 /* Zoned devices require I/O to be submitted in order. */
620 if ((bbio->bio.bi_opf & REQ_META) && btrfs_is_zoned(fs_info: bbio->fs_info))
621 return false;
622
623 return true;
624}
625
626/*
627 * Submit bio to an async queue.
628 *
629 * Return true if the work has been succesfuly submitted, else false.
630 */
631static bool btrfs_wq_submit_bio(struct btrfs_bio *bbio,
632 struct btrfs_io_context *bioc,
633 struct btrfs_io_stripe *smap, int mirror_num)
634{
635 struct btrfs_fs_info *fs_info = bbio->fs_info;
636 struct async_submit_bio *async;
637
638 async = kmalloc(size: sizeof(*async), GFP_NOFS);
639 if (!async)
640 return false;
641
642 async->bbio = bbio;
643 async->bioc = bioc;
644 async->smap = *smap;
645 async->mirror_num = mirror_num;
646
647 btrfs_init_work(work: &async->work, func: run_one_async_start, ordered_func: run_one_async_done);
648 btrfs_queue_work(wq: fs_info->workers, work: &async->work);
649 return true;
650}
651
652static bool btrfs_submit_chunk(struct btrfs_bio *bbio, int mirror_num)
653{
654 struct btrfs_inode *inode = bbio->inode;
655 struct btrfs_fs_info *fs_info = bbio->fs_info;
656 struct btrfs_bio *orig_bbio = bbio;
657 struct bio *bio = &bbio->bio;
658 u64 logical = bio->bi_iter.bi_sector << SECTOR_SHIFT;
659 u64 length = bio->bi_iter.bi_size;
660 u64 map_length = length;
661 bool use_append = btrfs_use_zone_append(bbio);
662 struct btrfs_io_context *bioc = NULL;
663 struct btrfs_io_stripe smap;
664 blk_status_t ret;
665 int error;
666
667 smap.is_scrub = !bbio->inode;
668
669 btrfs_bio_counter_inc_blocked(fs_info);
670 error = btrfs_map_block(fs_info, op: btrfs_op(bio), logical, length: &map_length,
671 bioc_ret: &bioc, smap: &smap, mirror_num_ret: &mirror_num);
672 if (error) {
673 ret = errno_to_blk_status(errno: error);
674 goto fail;
675 }
676
677 map_length = min(map_length, length);
678 if (use_append)
679 map_length = min(map_length, fs_info->max_zone_append_size);
680
681 if (map_length < length) {
682 bbio = btrfs_split_bio(fs_info, orig_bbio: bbio, map_length, use_append);
683 bio = &bbio->bio;
684 }
685
686 /*
687 * Save the iter for the end_io handler and preload the checksums for
688 * data reads.
689 */
690 if (bio_op(bio) == REQ_OP_READ && is_data_bbio(bbio)) {
691 bbio->saved_iter = bio->bi_iter;
692 ret = btrfs_lookup_bio_sums(bbio);
693 if (ret)
694 goto fail_put_bio;
695 }
696
697 if (btrfs_op(bio) == BTRFS_MAP_WRITE) {
698 if (use_append) {
699 bio->bi_opf &= ~REQ_OP_WRITE;
700 bio->bi_opf |= REQ_OP_ZONE_APPEND;
701 }
702
703 if (is_data_bbio(bbio) && bioc &&
704 btrfs_need_stripe_tree_update(fs_info: bioc->fs_info, map_type: bioc->map_type)) {
705 /*
706 * No locking for the list update, as we only add to
707 * the list in the I/O submission path, and list
708 * iteration only happens in the completion path, which
709 * can't happen until after the last submission.
710 */
711 btrfs_get_bioc(bioc);
712 list_add_tail(new: &bioc->rst_ordered_entry, head: &bbio->ordered->bioc_list);
713 }
714
715 /*
716 * Csum items for reloc roots have already been cloned at this
717 * point, so they are handled as part of the no-checksum case.
718 */
719 if (inode && !(inode->flags & BTRFS_INODE_NODATASUM) &&
720 !test_bit(BTRFS_FS_STATE_NO_CSUMS, &fs_info->fs_state) &&
721 !btrfs_is_data_reloc_root(root: inode->root)) {
722 if (should_async_write(bbio) &&
723 btrfs_wq_submit_bio(bbio, bioc, smap: &smap, mirror_num))
724 goto done;
725
726 ret = btrfs_bio_csum(bbio);
727 if (ret)
728 goto fail_put_bio;
729 } else if (use_append) {
730 ret = btrfs_alloc_dummy_sum(bbio);
731 if (ret)
732 goto fail_put_bio;
733 }
734 }
735
736 __btrfs_submit_bio(bio, bioc, smap: &smap, mirror_num);
737done:
738 return map_length == length;
739
740fail_put_bio:
741 if (map_length < length)
742 btrfs_cleanup_bio(bbio);
743fail:
744 btrfs_bio_counter_dec(fs_info);
745 btrfs_bio_end_io(bbio: orig_bbio, status: ret);
746 /* Do not submit another chunk */
747 return true;
748}
749
750void btrfs_submit_bio(struct btrfs_bio *bbio, int mirror_num)
751{
752 /* If bbio->inode is not populated, its file_offset must be 0. */
753 ASSERT(bbio->inode || bbio->file_offset == 0);
754
755 while (!btrfs_submit_chunk(bbio, mirror_num))
756 ;
757}
758
759/*
760 * Submit a repair write.
761 *
762 * This bypasses btrfs_submit_bio deliberately, as that writes all copies in a
763 * RAID setup. Here we only want to write the one bad copy, so we do the
764 * mapping ourselves and submit the bio directly.
765 *
766 * The I/O is issued synchronously to block the repair read completion from
767 * freeing the bio.
768 */
769int btrfs_repair_io_failure(struct btrfs_fs_info *fs_info, u64 ino, u64 start,
770 u64 length, u64 logical, struct page *page,
771 unsigned int pg_offset, int mirror_num)
772{
773 struct btrfs_io_stripe smap = { 0 };
774 struct bio_vec bvec;
775 struct bio bio;
776 int ret = 0;
777
778 ASSERT(!(fs_info->sb->s_flags & SB_RDONLY));
779 BUG_ON(!mirror_num);
780
781 if (btrfs_repair_one_zone(fs_info, logical))
782 return 0;
783
784 /*
785 * Avoid races with device replace and make sure our bioc has devices
786 * associated to its stripes that don't go away while we are doing the
787 * read repair operation.
788 */
789 btrfs_bio_counter_inc_blocked(fs_info);
790 ret = btrfs_map_repair_block(fs_info, smap: &smap, logical, length, mirror_num);
791 if (ret < 0)
792 goto out_counter_dec;
793
794 if (!smap.dev->bdev ||
795 !test_bit(BTRFS_DEV_STATE_WRITEABLE, &smap.dev->dev_state)) {
796 ret = -EIO;
797 goto out_counter_dec;
798 }
799
800 bio_init(bio: &bio, bdev: smap.dev->bdev, table: &bvec, max_vecs: 1, opf: REQ_OP_WRITE | REQ_SYNC);
801 bio.bi_iter.bi_sector = smap.physical >> SECTOR_SHIFT;
802 __bio_add_page(bio: &bio, page, len: length, off: pg_offset);
803 ret = submit_bio_wait(bio: &bio);
804 if (ret) {
805 /* try to remap that extent elsewhere? */
806 btrfs_dev_stat_inc_and_print(dev: smap.dev, index: BTRFS_DEV_STAT_WRITE_ERRS);
807 goto out_bio_uninit;
808 }
809
810 btrfs_info_rl_in_rcu(fs_info,
811 "read error corrected: ino %llu off %llu (dev %s sector %llu)",
812 ino, start, btrfs_dev_name(smap.dev),
813 smap.physical >> SECTOR_SHIFT);
814 ret = 0;
815
816out_bio_uninit:
817 bio_uninit(&bio);
818out_counter_dec:
819 btrfs_bio_counter_dec(fs_info);
820 return ret;
821}
822
823/*
824 * Submit a btrfs_bio based repair write.
825 *
826 * If @dev_replace is true, the write would be submitted to dev-replace target.
827 */
828void btrfs_submit_repair_write(struct btrfs_bio *bbio, int mirror_num, bool dev_replace)
829{
830 struct btrfs_fs_info *fs_info = bbio->fs_info;
831 u64 logical = bbio->bio.bi_iter.bi_sector << SECTOR_SHIFT;
832 u64 length = bbio->bio.bi_iter.bi_size;
833 struct btrfs_io_stripe smap = { 0 };
834 int ret;
835
836 ASSERT(fs_info);
837 ASSERT(mirror_num > 0);
838 ASSERT(btrfs_op(&bbio->bio) == BTRFS_MAP_WRITE);
839 ASSERT(!bbio->inode);
840
841 btrfs_bio_counter_inc_blocked(fs_info);
842 ret = btrfs_map_repair_block(fs_info, smap: &smap, logical, length, mirror_num);
843 if (ret < 0)
844 goto fail;
845
846 if (dev_replace) {
847 ASSERT(smap.dev == fs_info->dev_replace.srcdev);
848 smap.dev = fs_info->dev_replace.tgtdev;
849 }
850 __btrfs_submit_bio(bio: &bbio->bio, NULL, smap: &smap, mirror_num);
851 return;
852
853fail:
854 btrfs_bio_counter_dec(fs_info);
855 btrfs_bio_end_io(bbio, status: errno_to_blk_status(errno: ret));
856}
857
858int __init btrfs_bioset_init(void)
859{
860 if (bioset_init(&btrfs_bioset, BIO_POOL_SIZE,
861 offsetof(struct btrfs_bio, bio),
862 flags: BIOSET_NEED_BVECS))
863 return -ENOMEM;
864 if (bioset_init(&btrfs_clone_bioset, BIO_POOL_SIZE,
865 offsetof(struct btrfs_bio, bio), flags: 0))
866 goto out_free_bioset;
867 if (bioset_init(&btrfs_repair_bioset, BIO_POOL_SIZE,
868 offsetof(struct btrfs_bio, bio),
869 flags: BIOSET_NEED_BVECS))
870 goto out_free_clone_bioset;
871 if (mempool_init_kmalloc_pool(pool: &btrfs_failed_bio_pool, BIO_POOL_SIZE,
872 size: sizeof(struct btrfs_failed_bio)))
873 goto out_free_repair_bioset;
874 return 0;
875
876out_free_repair_bioset:
877 bioset_exit(&btrfs_repair_bioset);
878out_free_clone_bioset:
879 bioset_exit(&btrfs_clone_bioset);
880out_free_bioset:
881 bioset_exit(&btrfs_bioset);
882 return -ENOMEM;
883}
884
885void __cold btrfs_bioset_exit(void)
886{
887 mempool_exit(pool: &btrfs_failed_bio_pool);
888 bioset_exit(&btrfs_repair_bioset);
889 bioset_exit(&btrfs_clone_bioset);
890 bioset_exit(&btrfs_bioset);
891}
892

source code of linux/fs/btrfs/bio.c