projects/linux·blob v5.17 · refs

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1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * Copyright (C) 2001 Jens Axboe <[email protected]>
4 */
5#ifndef __LINUX_BIO_H
6#define __LINUX_BIO_H
7
8#include <linux/mempool.h>
9/* struct bio, bio_vec and BIO_* flags are defined in blk_types.h */
10#include <linux/blk_types.h>
11#include <linux/uio.h>
12
13#define BIO_MAX_VECS 256U
14
15static inline unsigned int bio_max_segs(unsigned int nr_segs)
16{
17 return min(nr_segs, BIO_MAX_VECS);
18}
19
20#define bio_prio(bio) (bio)->bi_ioprio
21#define bio_set_prio(bio, prio) ((bio)->bi_ioprio = prio)
22
23#define bio_iter_iovec(bio, iter) \
24 bvec_iter_bvec((bio)->bi_io_vec, (iter))
25
26#define bio_iter_page(bio, iter) \
27 bvec_iter_page((bio)->bi_io_vec, (iter))
28#define bio_iter_len(bio, iter) \
29 bvec_iter_len((bio)->bi_io_vec, (iter))
30#define bio_iter_offset(bio, iter) \
31 bvec_iter_offset((bio)->bi_io_vec, (iter))
32
33#define bio_page(bio) bio_iter_page((bio), (bio)->bi_iter)
34#define bio_offset(bio) bio_iter_offset((bio), (bio)->bi_iter)
35#define bio_iovec(bio) bio_iter_iovec((bio), (bio)->bi_iter)
36
37#define bvec_iter_sectors(iter) ((iter).bi_size >> 9)
38#define bvec_iter_end_sector(iter) ((iter).bi_sector + bvec_iter_sectors((iter)))
39
40#define bio_sectors(bio) bvec_iter_sectors((bio)->bi_iter)
41#define bio_end_sector(bio) bvec_iter_end_sector((bio)->bi_iter)
42
43/*
44 * Return the data direction, READ or WRITE.
45 */
46#define bio_data_dir(bio) \
47 (op_is_write(bio_op(bio)) ? WRITE : READ)
48
49/*
50 * Check whether this bio carries any data or not. A NULL bio is allowed.
51 */
52static inline bool bio_has_data(struct bio *bio)
53{
54 if (bio &&
55 bio->bi_iter.bi_size &&
56 bio_op(bio) != REQ_OP_DISCARD &&
57 bio_op(bio) != REQ_OP_SECURE_ERASE &&
58 bio_op(bio) != REQ_OP_WRITE_ZEROES)
59 return true;
60
61 return false;
62}
63
64static inline bool bio_no_advance_iter(const struct bio *bio)
65{
66 return bio_op(bio) == REQ_OP_DISCARD ||
67 bio_op(bio) == REQ_OP_SECURE_ERASE ||
68 bio_op(bio) == REQ_OP_WRITE_SAME ||
69 bio_op(bio) == REQ_OP_WRITE_ZEROES;
70}
71
72static inline void *bio_data(struct bio *bio)
73{
74 if (bio_has_data(bio))
75 return page_address(bio_page(bio)) + bio_offset(bio);
76
77 return NULL;
78}
79
80static inline bool bio_next_segment(const struct bio *bio,
81 struct bvec_iter_all *iter)
82{
83 if (iter->idx >= bio->bi_vcnt)
84 return false;
85
86 bvec_advance(&bio->bi_io_vec[iter->idx], iter);
87 return true;
88}
89
90/*
91 * drivers should _never_ use the all version - the bio may have been split
92 * before it got to the driver and the driver won't own all of it
93 */
94#define bio_for_each_segment_all(bvl, bio, iter) \
95 for (bvl = bvec_init_iter_all(&iter); bio_next_segment((bio), &iter); )
96
97static inline void bio_advance_iter(const struct bio *bio,
98 struct bvec_iter *iter, unsigned int bytes)
99{
100 iter->bi_sector += bytes >> 9;
101
102 if (bio_no_advance_iter(bio))
103 iter->bi_size -= bytes;
104 else
105 bvec_iter_advance(bio->bi_io_vec, iter, bytes);
106 /* TODO: It is reasonable to complete bio with error here. */
107}
108
109/* @bytes should be less or equal to bvec[i->bi_idx].bv_len */
110static inline void bio_advance_iter_single(const struct bio *bio,
111 struct bvec_iter *iter,
112 unsigned int bytes)
113{
114 iter->bi_sector += bytes >> 9;
115
116 if (bio_no_advance_iter(bio))
117 iter->bi_size -= bytes;
118 else
119 bvec_iter_advance_single(bio->bi_io_vec, iter, bytes);
120}
121
122void __bio_advance(struct bio *, unsigned bytes);
123
124/**
125 * bio_advance - increment/complete a bio by some number of bytes
126 * @bio: bio to advance
127 * @nbytes: number of bytes to complete
128 *
129 * This updates bi_sector, bi_size and bi_idx; if the number of bytes to
130 * complete doesn't align with a bvec boundary, then bv_len and bv_offset will
131 * be updated on the last bvec as well.
132 *
133 * @bio will then represent the remaining, uncompleted portion of the io.
134 */
135static inline void bio_advance(struct bio *bio, unsigned int nbytes)
136{
137 if (nbytes == bio->bi_iter.bi_size) {
138 bio->bi_iter.bi_size = 0;
139 return;
140 }
141 __bio_advance(bio, nbytes);
142}
143
144#define __bio_for_each_segment(bvl, bio, iter, start) \
145 for (iter = (start); \
146 (iter).bi_size && \
147 ((bvl = bio_iter_iovec((bio), (iter))), 1); \
148 bio_advance_iter_single((bio), &(iter), (bvl).bv_len))
149
150#define bio_for_each_segment(bvl, bio, iter) \
151 __bio_for_each_segment(bvl, bio, iter, (bio)->bi_iter)
152
153#define __bio_for_each_bvec(bvl, bio, iter, start) \
154 for (iter = (start); \
155 (iter).bi_size && \
156 ((bvl = mp_bvec_iter_bvec((bio)->bi_io_vec, (iter))), 1); \
157 bio_advance_iter_single((bio), &(iter), (bvl).bv_len))
158
159/* iterate over multi-page bvec */
160#define bio_for_each_bvec(bvl, bio, iter) \
161 __bio_for_each_bvec(bvl, bio, iter, (bio)->bi_iter)
162
163/*
164 * Iterate over all multi-page bvecs. Drivers shouldn't use this version for the
165 * same reasons as bio_for_each_segment_all().
166 */
167#define bio_for_each_bvec_all(bvl, bio, i) \
168 for (i = 0, bvl = bio_first_bvec_all(bio); \
169 i < (bio)->bi_vcnt; i++, bvl++)
170
171#define bio_iter_last(bvec, iter) ((iter).bi_size == (bvec).bv_len)
172
173static inline unsigned bio_segments(struct bio *bio)
174{
175 unsigned segs = 0;
176 struct bio_vec bv;
177 struct bvec_iter iter;
178
179 /*
180 * We special case discard/write same/write zeroes, because they
181 * interpret bi_size differently:
182 */
183
184 switch (bio_op(bio)) {
185 case REQ_OP_DISCARD:
186 case REQ_OP_SECURE_ERASE:
187 case REQ_OP_WRITE_ZEROES:
188 return 0;
189 case REQ_OP_WRITE_SAME:
190 return 1;
191 default:
192 break;
193 }
194
195 bio_for_each_segment(bv, bio, iter)
196 segs++;
197
198 return segs;
199}
200
201/*
202 * get a reference to a bio, so it won't disappear. the intended use is
203 * something like:
204 *
205 * bio_get(bio);
206 * submit_bio(rw, bio);
207 * if (bio->bi_flags ...)
208 * do_something
209 * bio_put(bio);
210 *
211 * without the bio_get(), it could potentially complete I/O before submit_bio
212 * returns. and then bio would be freed memory when if (bio->bi_flags ...)
213 * runs
214 */
215static inline void bio_get(struct bio *bio)
216{
217 bio->bi_flags |= (1 << BIO_REFFED);
218 smp_mb__before_atomic();
219 atomic_inc(&bio->__bi_cnt);
220}
221
222static inline void bio_cnt_set(struct bio *bio, unsigned int count)
223{
224 if (count != 1) {
225 bio->bi_flags |= (1 << BIO_REFFED);
226 smp_mb();
227 }
228 atomic_set(&bio->__bi_cnt, count);
229}
230
231static inline bool bio_flagged(struct bio *bio, unsigned int bit)
232{
233 return (bio->bi_flags & (1U << bit)) != 0;
234}
235
236static inline void bio_set_flag(struct bio *bio, unsigned int bit)
237{
238 bio->bi_flags |= (1U << bit);
239}
240
241static inline void bio_clear_flag(struct bio *bio, unsigned int bit)
242{
243 bio->bi_flags &= ~(1U << bit);
244}
245
246static inline struct bio_vec *bio_first_bvec_all(struct bio *bio)
247{
248 WARN_ON_ONCE(bio_flagged(bio, BIO_CLONED));
249 return bio->bi_io_vec;
250}
251
252static inline struct page *bio_first_page_all(struct bio *bio)
253{
254 return bio_first_bvec_all(bio)->bv_page;
255}
256
257static inline struct bio_vec *bio_last_bvec_all(struct bio *bio)
258{
259 WARN_ON_ONCE(bio_flagged(bio, BIO_CLONED));
260 return &bio->bi_io_vec[bio->bi_vcnt - 1];
261}
262
263/**
264 * struct folio_iter - State for iterating all folios in a bio.
265 * @folio: The current folio we're iterating. NULL after the last folio.
266 * @offset: The byte offset within the current folio.
267 * @length: The number of bytes in this iteration (will not cross folio
268 * boundary).
269 */
270struct folio_iter {
271 struct folio *folio;
272 size_t offset;
273 size_t length;
274 /* private: for use by the iterator */
275 size_t _seg_count;
276 int _i;
277};
278
279static inline void bio_first_folio(struct folio_iter *fi, struct bio *bio,
280 int i)
281{
282 struct bio_vec *bvec = bio_first_bvec_all(bio) + i;
283
284 fi->folio = page_folio(bvec->bv_page);
285 fi->offset = bvec->bv_offset +
286 PAGE_SIZE * (bvec->bv_page - &fi->folio->page);
287 fi->_seg_count = bvec->bv_len;
288 fi->length = min(folio_size(fi->folio) - fi->offset, fi->_seg_count);
289 fi->_i = i;
290}
291
292static inline void bio_next_folio(struct folio_iter *fi, struct bio *bio)
293{
294 fi->_seg_count -= fi->length;
295 if (fi->_seg_count) {
296 fi->folio = folio_next(fi->folio);
297 fi->offset = 0;
298 fi->length = min(folio_size(fi->folio), fi->_seg_count);
299 } else if (fi->_i + 1 < bio->bi_vcnt) {
300 bio_first_folio(fi, bio, fi->_i + 1);
301 } else {
302 fi->folio = NULL;
303 }
304}
305
306/**
307 * bio_for_each_folio_all - Iterate over each folio in a bio.
308 * @fi: struct folio_iter which is updated for each folio.
309 * @bio: struct bio to iterate over.
310 */
311#define bio_for_each_folio_all(fi, bio) \
312 for (bio_first_folio(&fi, bio, 0); fi.folio; bio_next_folio(&fi, bio))
313
314enum bip_flags {
315 BIP_BLOCK_INTEGRITY = 1 << 0, /* block layer owns integrity data */
316 BIP_MAPPED_INTEGRITY = 1 << 1, /* ref tag has been remapped */
317 BIP_CTRL_NOCHECK = 1 << 2, /* disable HBA integrity checking */
318 BIP_DISK_NOCHECK = 1 << 3, /* disable disk integrity checking */
319 BIP_IP_CHECKSUM = 1 << 4, /* IP checksum */
320};
321
322/*
323 * bio integrity payload
324 */
325struct bio_integrity_payload {
326 struct bio *bip_bio; /* parent bio */
327
328 struct bvec_iter bip_iter;
329
330 unsigned short bip_vcnt; /* # of integrity bio_vecs */
331 unsigned short bip_max_vcnt; /* integrity bio_vec slots */
332 unsigned short bip_flags; /* control flags */
333
334 struct bvec_iter bio_iter; /* for rewinding parent bio */
335
336 struct work_struct bip_work; /* I/O completion */
337
338 struct bio_vec *bip_vec;
339 struct bio_vec bip_inline_vecs[];/* embedded bvec array */
340};
341
342#if defined(CONFIG_BLK_DEV_INTEGRITY)
343
344static inline struct bio_integrity_payload *bio_integrity(struct bio *bio)
345{
346 if (bio->bi_opf & REQ_INTEGRITY)
347 return bio->bi_integrity;
348
349 return NULL;
350}
351
352static inline bool bio_integrity_flagged(struct bio *bio, enum bip_flags flag)
353{
354 struct bio_integrity_payload *bip = bio_integrity(bio);
355
356 if (bip)
357 return bip->bip_flags & flag;
358
359 return false;
360}
361
362static inline sector_t bip_get_seed(struct bio_integrity_payload *bip)
363{
364 return bip->bip_iter.bi_sector;
365}
366
367static inline void bip_set_seed(struct bio_integrity_payload *bip,
368 sector_t seed)
369{
370 bip->bip_iter.bi_sector = seed;
371}
372
373#endif /* CONFIG_BLK_DEV_INTEGRITY */
374
375void bio_trim(struct bio *bio, sector_t offset, sector_t size);
376extern struct bio *bio_split(struct bio *bio, int sectors,
377 gfp_t gfp, struct bio_set *bs);
378
379/**
380 * bio_next_split - get next @sectors from a bio, splitting if necessary
381 * @bio: bio to split
382 * @sectors: number of sectors to split from the front of @bio
383 * @gfp: gfp mask
384 * @bs: bio set to allocate from
385 *
386 * Return: a bio representing the next @sectors of @bio - if the bio is smaller
387 * than @sectors, returns the original bio unchanged.
388 */
389static inline struct bio *bio_next_split(struct bio *bio, int sectors,
390 gfp_t gfp, struct bio_set *bs)
391{
392 if (sectors >= bio_sectors(bio))
393 return bio;
394
395 return bio_split(bio, sectors, gfp, bs);
396}
397
398enum {
399 BIOSET_NEED_BVECS = BIT(0),
400 BIOSET_NEED_RESCUER = BIT(1),
401 BIOSET_PERCPU_CACHE = BIT(2),
402};
403extern int bioset_init(struct bio_set *, unsigned int, unsigned int, int flags);
404extern void bioset_exit(struct bio_set *);
405extern int biovec_init_pool(mempool_t *pool, int pool_entries);
406extern int bioset_init_from_src(struct bio_set *bs, struct bio_set *src);
407
408struct bio *bio_alloc_bioset(gfp_t gfp, unsigned short nr_iovecs,
409 struct bio_set *bs);
410struct bio *bio_alloc_kiocb(struct kiocb *kiocb, unsigned short nr_vecs,
411 struct bio_set *bs);
412struct bio *bio_kmalloc(gfp_t gfp_mask, unsigned short nr_iovecs);
413extern void bio_put(struct bio *);
414
415extern void __bio_clone_fast(struct bio *, struct bio *);
416extern struct bio *bio_clone_fast(struct bio *, gfp_t, struct bio_set *);
417
418extern struct bio_set fs_bio_set;
419
420static inline struct bio *bio_alloc(gfp_t gfp_mask, unsigned short nr_iovecs)
421{
422 return bio_alloc_bioset(gfp_mask, nr_iovecs, &fs_bio_set);
423}
424
425void submit_bio(struct bio *bio);
426
427extern void bio_endio(struct bio *);
428
429static inline void bio_io_error(struct bio *bio)
430{
431 bio->bi_status = BLK_STS_IOERR;
432 bio_endio(bio);
433}
434
435static inline void bio_wouldblock_error(struct bio *bio)
436{
437 bio_set_flag(bio, BIO_QUIET);
438 bio->bi_status = BLK_STS_AGAIN;
439 bio_endio(bio);
440}
441
442/*
443 * Calculate number of bvec segments that should be allocated to fit data
444 * pointed by @iter. If @iter is backed by bvec it's going to be reused
445 * instead of allocating a new one.
446 */
447static inline int bio_iov_vecs_to_alloc(struct iov_iter *iter, int max_segs)
448{
449 if (iov_iter_is_bvec(iter))
450 return 0;
451 return iov_iter_npages(iter, max_segs);
452}
453
454struct request_queue;
455
456extern int submit_bio_wait(struct bio *bio);
457extern void bio_init(struct bio *bio, struct bio_vec *table,
458 unsigned short max_vecs);
459extern void bio_uninit(struct bio *);
460extern void bio_reset(struct bio *);
461void bio_chain(struct bio *, struct bio *);
462
463int bio_add_page(struct bio *, struct page *, unsigned len, unsigned off);
464bool bio_add_folio(struct bio *, struct folio *, size_t len, size_t off);
465extern int bio_add_pc_page(struct request_queue *, struct bio *, struct page *,
466 unsigned int, unsigned int);
467int bio_add_zone_append_page(struct bio *bio, struct page *page,
468 unsigned int len, unsigned int offset);
469void __bio_add_page(struct bio *bio, struct page *page,
470 unsigned int len, unsigned int off);
471int bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter);
472void bio_iov_bvec_set(struct bio *bio, struct iov_iter *iter);
473void __bio_release_pages(struct bio *bio, bool mark_dirty);
474extern void bio_set_pages_dirty(struct bio *bio);
475extern void bio_check_pages_dirty(struct bio *bio);
476
477extern void bio_copy_data_iter(struct bio *dst, struct bvec_iter *dst_iter,
478 struct bio *src, struct bvec_iter *src_iter);
479extern void bio_copy_data(struct bio *dst, struct bio *src);
480extern void bio_free_pages(struct bio *bio);
481void guard_bio_eod(struct bio *bio);
482void zero_fill_bio(struct bio *bio);
483
484static inline void bio_release_pages(struct bio *bio, bool mark_dirty)
485{
486 if (!bio_flagged(bio, BIO_NO_PAGE_REF))
487 __bio_release_pages(bio, mark_dirty);
488}
489
490extern const char *bio_devname(struct bio *bio, char *buffer);
491
492#define bio_dev(bio) \
493 disk_devt((bio)->bi_bdev->bd_disk)
494
495#ifdef CONFIG_BLK_CGROUP
496void bio_associate_blkg(struct bio *bio);
497void bio_associate_blkg_from_css(struct bio *bio,
498 struct cgroup_subsys_state *css);
499void bio_clone_blkg_association(struct bio *dst, struct bio *src);
500#else /* CONFIG_BLK_CGROUP */
501static inline void bio_associate_blkg(struct bio *bio) { }
502static inline void bio_associate_blkg_from_css(struct bio *bio,
503 struct cgroup_subsys_state *css)
504{ }
505static inline void bio_clone_blkg_association(struct bio *dst,
506 struct bio *src) { }
507#endif /* CONFIG_BLK_CGROUP */
508
509static inline void bio_set_dev(struct bio *bio, struct block_device *bdev)
510{
511 bio_clear_flag(bio, BIO_REMAPPED);
512 if (bio->bi_bdev != bdev)
513 bio_clear_flag(bio, BIO_THROTTLED);
514 bio->bi_bdev = bdev;
515 bio_associate_blkg(bio);
516}
517
518static inline void bio_copy_dev(struct bio *dst, struct bio *src)
519{
520 bio_clear_flag(dst, BIO_REMAPPED);
521 dst->bi_bdev = src->bi_bdev;
522 bio_clone_blkg_association(dst, src);
523}
524
525/*
526 * BIO list management for use by remapping drivers (e.g. DM or MD) and loop.
527 *
528 * A bio_list anchors a singly-linked list of bios chained through the bi_next
529 * member of the bio. The bio_list also caches the last list member to allow
530 * fast access to the tail.
531 */
532struct bio_list {
533 struct bio *head;
534 struct bio *tail;
535};
536
537static inline int bio_list_empty(const struct bio_list *bl)
538{
539 return bl->head == NULL;
540}
541
542static inline void bio_list_init(struct bio_list *bl)
543{
544 bl->head = bl->tail = NULL;
545}
546
547#define BIO_EMPTY_LIST { NULL, NULL }
548
549#define bio_list_for_each(bio, bl) \
550 for (bio = (bl)->head; bio; bio = bio->bi_next)
551
552static inline unsigned bio_list_size(const struct bio_list *bl)
553{
554 unsigned sz = 0;
555 struct bio *bio;
556
557 bio_list_for_each(bio, bl)
558 sz++;
559
560 return sz;
561}
562
563static inline void bio_list_add(struct bio_list *bl, struct bio *bio)
564{
565 bio->bi_next = NULL;
566
567 if (bl->tail)
568 bl->tail->bi_next = bio;
569 else
570 bl->head = bio;
571
572 bl->tail = bio;
573}
574
575static inline void bio_list_add_head(struct bio_list *bl, struct bio *bio)
576{
577 bio->bi_next = bl->head;
578
579 bl->head = bio;
580
581 if (!bl->tail)
582 bl->tail = bio;
583}
584
585static inline void bio_list_merge(struct bio_list *bl, struct bio_list *bl2)
586{
587 if (!bl2->head)
588 return;
589
590 if (bl->tail)
591 bl->tail->bi_next = bl2->head;
592 else
593 bl->head = bl2->head;
594
595 bl->tail = bl2->tail;
596}
597
598static inline void bio_list_merge_head(struct bio_list *bl,
599 struct bio_list *bl2)
600{
601 if (!bl2->head)
602 return;
603
604 if (bl->head)
605 bl2->tail->bi_next = bl->head;
606 else
607 bl->tail = bl2->tail;
608
609 bl->head = bl2->head;
610}
611
612static inline struct bio *bio_list_peek(struct bio_list *bl)
613{
614 return bl->head;
615}
616
617static inline struct bio *bio_list_pop(struct bio_list *bl)
618{
619 struct bio *bio = bl->head;
620
621 if (bio) {
622 bl->head = bl->head->bi_next;
623 if (!bl->head)
624 bl->tail = NULL;
625
626 bio->bi_next = NULL;
627 }
628
629 return bio;
630}
631
632static inline struct bio *bio_list_get(struct bio_list *bl)
633{
634 struct bio *bio = bl->head;
635
636 bl->head = bl->tail = NULL;
637
638 return bio;
639}
640
641/*
642 * Increment chain count for the bio. Make sure the CHAIN flag update
643 * is visible before the raised count.
644 */
645static inline void bio_inc_remaining(struct bio *bio)
646{
647 bio_set_flag(bio, BIO_CHAIN);
648 smp_mb__before_atomic();
649 atomic_inc(&bio->__bi_remaining);
650}
651
652/*
653 * bio_set is used to allow other portions of the IO system to
654 * allocate their own private memory pools for bio and iovec structures.
655 * These memory pools in turn all allocate from the bio_slab
656 * and the bvec_slabs[].
657 */
658#define BIO_POOL_SIZE 2
659
660struct bio_set {
661 struct kmem_cache *bio_slab;
662 unsigned int front_pad;
663
664 /*
665 * per-cpu bio alloc cache
666 */
667 struct bio_alloc_cache __percpu *cache;
668
669 mempool_t bio_pool;
670 mempool_t bvec_pool;
671#if defined(CONFIG_BLK_DEV_INTEGRITY)
672 mempool_t bio_integrity_pool;
673 mempool_t bvec_integrity_pool;
674#endif
675
676 unsigned int back_pad;
677 /*
678 * Deadlock avoidance for stacking block drivers: see comments in
679 * bio_alloc_bioset() for details
680 */
681 spinlock_t rescue_lock;
682 struct bio_list rescue_list;
683 struct work_struct rescue_work;
684 struct workqueue_struct *rescue_workqueue;
685
686 /*
687 * Hot un-plug notifier for the per-cpu cache, if used
688 */
689 struct hlist_node cpuhp_dead;
690};
691
692static inline bool bioset_initialized(struct bio_set *bs)
693{
694 return bs->bio_slab != NULL;
695}
696
697#if defined(CONFIG_BLK_DEV_INTEGRITY)
698
699#define bip_for_each_vec(bvl, bip, iter) \
700 for_each_bvec(bvl, (bip)->bip_vec, iter, (bip)->bip_iter)
701
702#define bio_for_each_integrity_vec(_bvl, _bio, _iter) \
703 for_each_bio(_bio) \
704 bip_for_each_vec(_bvl, _bio->bi_integrity, _iter)
705
706extern struct bio_integrity_payload *bio_integrity_alloc(struct bio *, gfp_t, unsigned int);
707extern int bio_integrity_add_page(struct bio *, struct page *, unsigned int, unsigned int);
708extern bool bio_integrity_prep(struct bio *);
709extern void bio_integrity_advance(struct bio *, unsigned int);
710extern void bio_integrity_trim(struct bio *);
711extern int bio_integrity_clone(struct bio *, struct bio *, gfp_t);
712extern int bioset_integrity_create(struct bio_set *, int);
713extern void bioset_integrity_free(struct bio_set *);
714extern void bio_integrity_init(void);
715
716#else /* CONFIG_BLK_DEV_INTEGRITY */
717
718static inline void *bio_integrity(struct bio *bio)
719{
720 return NULL;
721}
722
723static inline int bioset_integrity_create(struct bio_set *bs, int pool_size)
724{
725 return 0;
726}
727
728static inline void bioset_integrity_free (struct bio_set *bs)
729{
730 return;
731}
732
733static inline bool bio_integrity_prep(struct bio *bio)
734{
735 return true;
736}
737
738static inline int bio_integrity_clone(struct bio *bio, struct bio *bio_src,
739 gfp_t gfp_mask)
740{
741 return 0;
742}
743
744static inline void bio_integrity_advance(struct bio *bio,
745 unsigned int bytes_done)
746{
747 return;
748}
749
750static inline void bio_integrity_trim(struct bio *bio)
751{
752 return;
753}
754
755static inline void bio_integrity_init(void)
756{
757 return;
758}
759
760static inline bool bio_integrity_flagged(struct bio *bio, enum bip_flags flag)
761{
762 return false;
763}
764
765static inline void *bio_integrity_alloc(struct bio * bio, gfp_t gfp,
766 unsigned int nr)
767{
768 return ERR_PTR(-EINVAL);
769}
770
771static inline int bio_integrity_add_page(struct bio *bio, struct page *page,
772 unsigned int len, unsigned int offset)
773{
774 return 0;
775}
776
777#endif /* CONFIG_BLK_DEV_INTEGRITY */
778
779/*
780 * Mark a bio as polled. Note that for async polled IO, the caller must
781 * expect -EWOULDBLOCK if we cannot allocate a request (or other resources).
782 * We cannot block waiting for requests on polled IO, as those completions
783 * must be found by the caller. This is different than IRQ driven IO, where
784 * it's safe to wait for IO to complete.
785 */
786static inline void bio_set_polled(struct bio *bio, struct kiocb *kiocb)
787{
788 bio->bi_opf |= REQ_POLLED;
789 if (!is_sync_kiocb(kiocb))
790 bio->bi_opf |= REQ_NOWAIT;
791}
792
793struct bio *blk_next_bio(struct bio *bio, unsigned int nr_pages, gfp_t gfp);
794
795#endif /* __LINUX_BIO_H */