Line data Source code
1 : /* SPDX-License-Identifier: GPL-2.0 */
2 : /*
3 : * Copyright (C) 2001 Jens Axboe <axboe@suse.de>
4 : */
5 : #ifndef __LINUX_BIO_H
6 : #define __LINUX_BIO_H
7 :
8 : #include <linux/highmem.h>
9 : #include <linux/mempool.h>
10 : #include <linux/ioprio.h>
11 : /* struct bio, bio_vec and BIO_* flags are defined in blk_types.h */
12 : #include <linux/blk_types.h>
13 : #include <linux/uio.h>
14 :
15 : #define BIO_DEBUG
16 :
17 : #ifdef BIO_DEBUG
18 : #define BIO_BUG_ON BUG_ON
19 : #else
20 : #define BIO_BUG_ON
21 : #endif
22 :
23 : #define BIO_MAX_VECS 256U
24 :
25 1749 : static inline unsigned int bio_max_segs(unsigned int nr_segs)
26 : {
27 1749 : return min(nr_segs, BIO_MAX_VECS);
28 : }
29 :
30 : #define bio_prio(bio) (bio)->bi_ioprio
31 : #define bio_set_prio(bio, prio) ((bio)->bi_ioprio = prio)
32 :
33 : #define bio_iter_iovec(bio, iter) \
34 : bvec_iter_bvec((bio)->bi_io_vec, (iter))
35 :
36 : #define bio_iter_page(bio, iter) \
37 : bvec_iter_page((bio)->bi_io_vec, (iter))
38 : #define bio_iter_len(bio, iter) \
39 : bvec_iter_len((bio)->bi_io_vec, (iter))
40 : #define bio_iter_offset(bio, iter) \
41 : bvec_iter_offset((bio)->bi_io_vec, (iter))
42 :
43 : #define bio_page(bio) bio_iter_page((bio), (bio)->bi_iter)
44 : #define bio_offset(bio) bio_iter_offset((bio), (bio)->bi_iter)
45 : #define bio_iovec(bio) bio_iter_iovec((bio), (bio)->bi_iter)
46 :
47 : #define bio_multiple_segments(bio) \
48 : ((bio)->bi_iter.bi_size != bio_iovec(bio).bv_len)
49 :
50 : #define bvec_iter_sectors(iter) ((iter).bi_size >> 9)
51 : #define bvec_iter_end_sector(iter) ((iter).bi_sector + bvec_iter_sectors((iter)))
52 :
53 : #define bio_sectors(bio) bvec_iter_sectors((bio)->bi_iter)
54 : #define bio_end_sector(bio) bvec_iter_end_sector((bio)->bi_iter)
55 :
56 : /*
57 : * Return the data direction, READ or WRITE.
58 : */
59 : #define bio_data_dir(bio) \
60 : (op_is_write(bio_op(bio)) ? WRITE : READ)
61 :
62 : /*
63 : * Check whether this bio carries any data or not. A NULL bio is allowed.
64 : */
65 14223 : static inline bool bio_has_data(struct bio *bio)
66 : {
67 14223 : if (bio &&
68 14223 : bio->bi_iter.bi_size &&
69 14151 : bio_op(bio) != REQ_OP_DISCARD &&
70 14151 : bio_op(bio) != REQ_OP_SECURE_ERASE &&
71 : bio_op(bio) != REQ_OP_WRITE_ZEROES)
72 14151 : return true;
73 :
74 : return false;
75 : }
76 :
77 26706 : static inline bool bio_no_advance_iter(const struct bio *bio)
78 : {
79 26706 : return bio_op(bio) == REQ_OP_DISCARD ||
80 26706 : bio_op(bio) == REQ_OP_SECURE_ERASE ||
81 53412 : bio_op(bio) == REQ_OP_WRITE_SAME ||
82 : bio_op(bio) == REQ_OP_WRITE_ZEROES;
83 : }
84 :
85 12545 : static inline bool bio_mergeable(struct bio *bio)
86 : {
87 12545 : if (bio->bi_opf & REQ_NOMERGE_FLAGS)
88 : return false;
89 :
90 : return true;
91 : }
92 :
93 0 : static inline unsigned int bio_cur_bytes(struct bio *bio)
94 : {
95 0 : if (bio_has_data(bio))
96 0 : return bio_iovec(bio).bv_len;
97 : else /* dataless requests such as discard */
98 0 : return bio->bi_iter.bi_size;
99 : }
100 :
101 : static inline void *bio_data(struct bio *bio)
102 : {
103 : if (bio_has_data(bio))
104 : return page_address(bio_page(bio)) + bio_offset(bio);
105 :
106 : return NULL;
107 : }
108 :
109 : /**
110 : * bio_full - check if the bio is full
111 : * @bio: bio to check
112 : * @len: length of one segment to be added
113 : *
114 : * Return true if @bio is full and one segment with @len bytes can't be
115 : * added to the bio, otherwise return false
116 : */
117 25178 : static inline bool bio_full(struct bio *bio, unsigned len)
118 : {
119 25178 : if (bio->bi_vcnt >= bio->bi_max_vecs)
120 : return true;
121 :
122 25178 : if (bio->bi_iter.bi_size > UINT_MAX - len)
123 0 : return true;
124 :
125 : return false;
126 : }
127 :
128 23922 : static inline bool bio_next_segment(const struct bio *bio,
129 : struct bvec_iter_all *iter)
130 : {
131 23922 : if (iter->idx >= bio->bi_vcnt)
132 : return false;
133 :
134 22053 : bvec_advance(&bio->bi_io_vec[iter->idx], iter);
135 22053 : return true;
136 : }
137 :
138 : /*
139 : * drivers should _never_ use the all version - the bio may have been split
140 : * before it got to the driver and the driver won't own all of it
141 : */
142 : #define bio_for_each_segment_all(bvl, bio, iter) \
143 : for (bvl = bvec_init_iter_all(&iter); bio_next_segment((bio), &iter); )
144 :
145 8798 : static inline void bio_advance_iter(const struct bio *bio,
146 : struct bvec_iter *iter, unsigned int bytes)
147 : {
148 8798 : iter->bi_sector += bytes >> 9;
149 :
150 8798 : if (bio_no_advance_iter(bio))
151 0 : iter->bi_size -= bytes;
152 : else
153 8798 : bvec_iter_advance(bio->bi_io_vec, iter, bytes);
154 : /* TODO: It is reasonable to complete bio with error here. */
155 8799 : }
156 :
157 : /* @bytes should be less or equal to bvec[i->bi_idx].bv_len */
158 17907 : static inline void bio_advance_iter_single(const struct bio *bio,
159 : struct bvec_iter *iter,
160 : unsigned int bytes)
161 : {
162 17907 : iter->bi_sector += bytes >> 9;
163 :
164 17907 : if (bio_no_advance_iter(bio))
165 0 : iter->bi_size -= bytes;
166 : else
167 17907 : bvec_iter_advance_single(bio->bi_io_vec, iter, bytes);
168 17907 : }
169 :
170 : #define __bio_for_each_segment(bvl, bio, iter, start) \
171 : for (iter = (start); \
172 : (iter).bi_size && \
173 : ((bvl = bio_iter_iovec((bio), (iter))), 1); \
174 : bio_advance_iter_single((bio), &(iter), (bvl).bv_len))
175 :
176 : #define bio_for_each_segment(bvl, bio, iter) \
177 : __bio_for_each_segment(bvl, bio, iter, (bio)->bi_iter)
178 :
179 : #define __bio_for_each_bvec(bvl, bio, iter, start) \
180 : for (iter = (start); \
181 : (iter).bi_size && \
182 : ((bvl = mp_bvec_iter_bvec((bio)->bi_io_vec, (iter))), 1); \
183 : bio_advance_iter_single((bio), &(iter), (bvl).bv_len))
184 :
185 : /* iterate over multi-page bvec */
186 : #define bio_for_each_bvec(bvl, bio, iter) \
187 : __bio_for_each_bvec(bvl, bio, iter, (bio)->bi_iter)
188 :
189 : /*
190 : * Iterate over all multi-page bvecs. Drivers shouldn't use this version for the
191 : * same reasons as bio_for_each_segment_all().
192 : */
193 : #define bio_for_each_bvec_all(bvl, bio, i) \
194 : for (i = 0, bvl = bio_first_bvec_all(bio); \
195 : i < (bio)->bi_vcnt; i++, bvl++) \
196 :
197 : #define bio_iter_last(bvec, iter) ((iter).bi_size == (bvec).bv_len)
198 :
199 : static inline unsigned bio_segments(struct bio *bio)
200 : {
201 : unsigned segs = 0;
202 : struct bio_vec bv;
203 : struct bvec_iter iter;
204 :
205 : /*
206 : * We special case discard/write same/write zeroes, because they
207 : * interpret bi_size differently:
208 : */
209 :
210 : switch (bio_op(bio)) {
211 : case REQ_OP_DISCARD:
212 : case REQ_OP_SECURE_ERASE:
213 : case REQ_OP_WRITE_ZEROES:
214 : return 0;
215 : case REQ_OP_WRITE_SAME:
216 : return 1;
217 : default:
218 : break;
219 : }
220 :
221 : bio_for_each_segment(bv, bio, iter)
222 : segs++;
223 :
224 : return segs;
225 : }
226 :
227 : /*
228 : * get a reference to a bio, so it won't disappear. the intended use is
229 : * something like:
230 : *
231 : * bio_get(bio);
232 : * submit_bio(rw, bio);
233 : * if (bio->bi_flags ...)
234 : * do_something
235 : * bio_put(bio);
236 : *
237 : * without the bio_get(), it could potentially complete I/O before submit_bio
238 : * returns. and then bio would be freed memory when if (bio->bi_flags ...)
239 : * runs
240 : */
241 0 : static inline void bio_get(struct bio *bio)
242 : {
243 0 : bio->bi_flags |= (1 << BIO_REFFED);
244 0 : smp_mb__before_atomic();
245 0 : atomic_inc(&bio->__bi_cnt);
246 0 : }
247 :
248 : static inline void bio_cnt_set(struct bio *bio, unsigned int count)
249 : {
250 : if (count != 1) {
251 : bio->bi_flags |= (1 << BIO_REFFED);
252 : smp_mb();
253 : }
254 : atomic_set(&bio->__bi_cnt, count);
255 : }
256 :
257 110279 : static inline bool bio_flagged(struct bio *bio, unsigned int bit)
258 : {
259 110279 : return (bio->bi_flags & (1U << bit)) != 0;
260 : }
261 :
262 20676 : static inline void bio_set_flag(struct bio *bio, unsigned int bit)
263 : {
264 20676 : bio->bi_flags |= (1U << bit);
265 8735 : }
266 :
267 26103 : static inline void bio_clear_flag(struct bio *bio, unsigned int bit)
268 : {
269 17451 : bio->bi_flags &= ~(1U << bit);
270 8652 : }
271 :
272 0 : static inline void bio_get_first_bvec(struct bio *bio, struct bio_vec *bv)
273 : {
274 0 : *bv = bio_iovec(bio);
275 0 : }
276 :
277 0 : static inline void bio_get_last_bvec(struct bio *bio, struct bio_vec *bv)
278 : {
279 0 : struct bvec_iter iter = bio->bi_iter;
280 0 : int idx;
281 :
282 0 : if (unlikely(!bio_multiple_segments(bio))) {
283 0 : *bv = bio_iovec(bio);
284 0 : return;
285 : }
286 :
287 0 : bio_advance_iter(bio, &iter, iter.bi_size);
288 :
289 0 : if (!iter.bi_bvec_done)
290 0 : idx = iter.bi_idx - 1;
291 : else /* in the middle of bvec */
292 0 : idx = iter.bi_idx;
293 :
294 0 : *bv = bio->bi_io_vec[idx];
295 :
296 : /*
297 : * iter.bi_bvec_done records actual length of the last bvec
298 : * if this bio ends in the middle of one io vector
299 : */
300 0 : if (iter.bi_bvec_done)
301 0 : bv->bv_len = iter.bi_bvec_done;
302 : }
303 :
304 : static inline struct bio_vec *bio_first_bvec_all(struct bio *bio)
305 : {
306 : WARN_ON_ONCE(bio_flagged(bio, BIO_CLONED));
307 : return bio->bi_io_vec;
308 : }
309 :
310 : static inline struct page *bio_first_page_all(struct bio *bio)
311 : {
312 : return bio_first_bvec_all(bio)->bv_page;
313 : }
314 :
315 : static inline struct bio_vec *bio_last_bvec_all(struct bio *bio)
316 : {
317 : WARN_ON_ONCE(bio_flagged(bio, BIO_CLONED));
318 : return &bio->bi_io_vec[bio->bi_vcnt - 1];
319 : }
320 :
321 : enum bip_flags {
322 : BIP_BLOCK_INTEGRITY = 1 << 0, /* block layer owns integrity data */
323 : BIP_MAPPED_INTEGRITY = 1 << 1, /* ref tag has been remapped */
324 : BIP_CTRL_NOCHECK = 1 << 2, /* disable HBA integrity checking */
325 : BIP_DISK_NOCHECK = 1 << 3, /* disable disk integrity checking */
326 : BIP_IP_CHECKSUM = 1 << 4, /* IP checksum */
327 : };
328 :
329 : /*
330 : * bio integrity payload
331 : */
332 : struct bio_integrity_payload {
333 : struct bio *bip_bio; /* parent bio */
334 :
335 : struct bvec_iter bip_iter;
336 :
337 : unsigned short bip_vcnt; /* # of integrity bio_vecs */
338 : unsigned short bip_max_vcnt; /* integrity bio_vec slots */
339 : unsigned short bip_flags; /* control flags */
340 :
341 : struct bvec_iter bio_iter; /* for rewinding parent bio */
342 :
343 : struct work_struct bip_work; /* I/O completion */
344 :
345 : struct bio_vec *bip_vec;
346 : struct bio_vec bip_inline_vecs[];/* embedded bvec array */
347 : };
348 :
349 : #if defined(CONFIG_BLK_DEV_INTEGRITY)
350 :
351 : static inline struct bio_integrity_payload *bio_integrity(struct bio *bio)
352 : {
353 : if (bio->bi_opf & REQ_INTEGRITY)
354 : return bio->bi_integrity;
355 :
356 : return NULL;
357 : }
358 :
359 : static inline bool bio_integrity_flagged(struct bio *bio, enum bip_flags flag)
360 : {
361 : struct bio_integrity_payload *bip = bio_integrity(bio);
362 :
363 : if (bip)
364 : return bip->bip_flags & flag;
365 :
366 : return false;
367 : }
368 :
369 : static inline sector_t bip_get_seed(struct bio_integrity_payload *bip)
370 : {
371 : return bip->bip_iter.bi_sector;
372 : }
373 :
374 : static inline void bip_set_seed(struct bio_integrity_payload *bip,
375 : sector_t seed)
376 : {
377 : bip->bip_iter.bi_sector = seed;
378 : }
379 :
380 : #endif /* CONFIG_BLK_DEV_INTEGRITY */
381 :
382 : extern void bio_trim(struct bio *bio, int offset, int size);
383 : extern struct bio *bio_split(struct bio *bio, int sectors,
384 : gfp_t gfp, struct bio_set *bs);
385 :
386 : /**
387 : * bio_next_split - get next @sectors from a bio, splitting if necessary
388 : * @bio: bio to split
389 : * @sectors: number of sectors to split from the front of @bio
390 : * @gfp: gfp mask
391 : * @bs: bio set to allocate from
392 : *
393 : * Returns a bio representing the next @sectors of @bio - if the bio is smaller
394 : * than @sectors, returns the original bio unchanged.
395 : */
396 : static inline struct bio *bio_next_split(struct bio *bio, int sectors,
397 : gfp_t gfp, struct bio_set *bs)
398 : {
399 : if (sectors >= bio_sectors(bio))
400 : return bio;
401 :
402 : return bio_split(bio, sectors, gfp, bs);
403 : }
404 :
405 : enum {
406 : BIOSET_NEED_BVECS = BIT(0),
407 : BIOSET_NEED_RESCUER = BIT(1),
408 : };
409 : extern int bioset_init(struct bio_set *, unsigned int, unsigned int, int flags);
410 : extern void bioset_exit(struct bio_set *);
411 : extern int biovec_init_pool(mempool_t *pool, int pool_entries);
412 : extern int bioset_init_from_src(struct bio_set *bs, struct bio_set *src);
413 :
414 : struct bio *bio_alloc_bioset(gfp_t gfp, unsigned short nr_iovecs,
415 : struct bio_set *bs);
416 : struct bio *bio_kmalloc(gfp_t gfp_mask, unsigned short nr_iovecs);
417 : extern void bio_put(struct bio *);
418 :
419 : extern void __bio_clone_fast(struct bio *, struct bio *);
420 : extern struct bio *bio_clone_fast(struct bio *, gfp_t, struct bio_set *);
421 :
422 : extern struct bio_set fs_bio_set;
423 :
424 8580 : static inline struct bio *bio_alloc(gfp_t gfp_mask, unsigned short nr_iovecs)
425 : {
426 8580 : return bio_alloc_bioset(gfp_mask, nr_iovecs, &fs_bio_set);
427 : }
428 :
429 : extern blk_qc_t submit_bio(struct bio *);
430 :
431 : extern void bio_endio(struct bio *);
432 :
433 0 : static inline void bio_io_error(struct bio *bio)
434 : {
435 0 : bio->bi_status = BLK_STS_IOERR;
436 0 : bio_endio(bio);
437 0 : }
438 :
439 0 : static inline void bio_wouldblock_error(struct bio *bio)
440 : {
441 0 : bio_set_flag(bio, BIO_QUIET);
442 0 : bio->bi_status = BLK_STS_AGAIN;
443 0 : bio_endio(bio);
444 0 : }
445 :
446 : /*
447 : * Calculate number of bvec segments that should be allocated to fit data
448 : * pointed by @iter. If @iter is backed by bvec it's going to be reused
449 : * instead of allocating a new one.
450 : */
451 0 : static inline int bio_iov_vecs_to_alloc(struct iov_iter *iter, int max_segs)
452 : {
453 0 : if (iov_iter_is_bvec(iter))
454 : return 0;
455 0 : return iov_iter_npages(iter, max_segs);
456 : }
457 :
458 : struct request_queue;
459 :
460 : extern int submit_bio_wait(struct bio *bio);
461 : extern void bio_advance(struct bio *, unsigned);
462 :
463 : extern void bio_init(struct bio *bio, struct bio_vec *table,
464 : unsigned short max_vecs);
465 : extern void bio_uninit(struct bio *);
466 : extern void bio_reset(struct bio *);
467 : void bio_chain(struct bio *, struct bio *);
468 :
469 : extern int bio_add_page(struct bio *, struct page *, unsigned int,unsigned int);
470 : extern int bio_add_pc_page(struct request_queue *, struct bio *, struct page *,
471 : unsigned int, unsigned int);
472 : int bio_add_zone_append_page(struct bio *bio, struct page *page,
473 : unsigned int len, unsigned int offset);
474 : bool __bio_try_merge_page(struct bio *bio, struct page *page,
475 : unsigned int len, unsigned int off, bool *same_page);
476 : void __bio_add_page(struct bio *bio, struct page *page,
477 : unsigned int len, unsigned int off);
478 : int bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter);
479 : void bio_release_pages(struct bio *bio, bool mark_dirty);
480 : extern void bio_set_pages_dirty(struct bio *bio);
481 : extern void bio_check_pages_dirty(struct bio *bio);
482 :
483 : extern void bio_copy_data_iter(struct bio *dst, struct bvec_iter *dst_iter,
484 : struct bio *src, struct bvec_iter *src_iter);
485 : extern void bio_copy_data(struct bio *dst, struct bio *src);
486 : extern void bio_list_copy_data(struct bio *dst, struct bio *src);
487 : extern void bio_free_pages(struct bio *bio);
488 : void zero_fill_bio_iter(struct bio *bio, struct bvec_iter iter);
489 : void bio_truncate(struct bio *bio, unsigned new_size);
490 : void guard_bio_eod(struct bio *bio);
491 :
492 0 : static inline void zero_fill_bio(struct bio *bio)
493 : {
494 0 : zero_fill_bio_iter(bio, bio->bi_iter);
495 0 : }
496 :
497 : extern const char *bio_devname(struct bio *bio, char *buffer);
498 :
499 : #define bio_set_dev(bio, bdev) \
500 : do { \
501 : bio_clear_flag(bio, BIO_REMAPPED); \
502 : if ((bio)->bi_bdev != (bdev)) \
503 : bio_clear_flag(bio, BIO_THROTTLED); \
504 : (bio)->bi_bdev = (bdev); \
505 : bio_associate_blkg(bio); \
506 : } while (0)
507 :
508 : #define bio_copy_dev(dst, src) \
509 : do { \
510 : bio_clear_flag(dst, BIO_REMAPPED); \
511 : (dst)->bi_bdev = (src)->bi_bdev; \
512 : bio_clone_blkg_association(dst, src); \
513 : } while (0)
514 :
515 : #define bio_dev(bio) \
516 : disk_devt((bio)->bi_bdev->bd_disk)
517 :
518 : #ifdef CONFIG_BLK_CGROUP
519 : void bio_associate_blkg(struct bio *bio);
520 : void bio_associate_blkg_from_css(struct bio *bio,
521 : struct cgroup_subsys_state *css);
522 : void bio_clone_blkg_association(struct bio *dst, struct bio *src);
523 : #else /* CONFIG_BLK_CGROUP */
524 8652 : static inline void bio_associate_blkg(struct bio *bio) { }
525 : static inline void bio_associate_blkg_from_css(struct bio *bio,
526 : struct cgroup_subsys_state *css)
527 : { }
528 0 : static inline void bio_clone_blkg_association(struct bio *dst,
529 0 : struct bio *src) { }
530 : #endif /* CONFIG_BLK_CGROUP */
531 :
532 : #ifdef CONFIG_HIGHMEM
533 : /*
534 : * remember never ever reenable interrupts between a bvec_kmap_irq and
535 : * bvec_kunmap_irq!
536 : */
537 : static inline char *bvec_kmap_irq(struct bio_vec *bvec, unsigned long *flags)
538 : {
539 : unsigned long addr;
540 :
541 : /*
542 : * might not be a highmem page, but the preempt/irq count
543 : * balancing is a lot nicer this way
544 : */
545 : local_irq_save(*flags);
546 : addr = (unsigned long) kmap_atomic(bvec->bv_page);
547 :
548 : BUG_ON(addr & ~PAGE_MASK);
549 :
550 : return (char *) addr + bvec->bv_offset;
551 : }
552 :
553 : static inline void bvec_kunmap_irq(char *buffer, unsigned long *flags)
554 : {
555 : unsigned long ptr = (unsigned long) buffer & PAGE_MASK;
556 :
557 : kunmap_atomic((void *) ptr);
558 : local_irq_restore(*flags);
559 : }
560 :
561 : #else
562 0 : static inline char *bvec_kmap_irq(struct bio_vec *bvec, unsigned long *flags)
563 : {
564 0 : return page_address(bvec->bv_page) + bvec->bv_offset;
565 : }
566 :
567 0 : static inline void bvec_kunmap_irq(char *buffer, unsigned long *flags)
568 : {
569 0 : *flags = 0;
570 : }
571 : #endif
572 :
573 : /*
574 : * BIO list management for use by remapping drivers (e.g. DM or MD) and loop.
575 : *
576 : * A bio_list anchors a singly-linked list of bios chained through the bi_next
577 : * member of the bio. The bio_list also caches the last list member to allow
578 : * fast access to the tail.
579 : */
580 : struct bio_list {
581 : struct bio *head;
582 : struct bio *tail;
583 : };
584 :
585 0 : static inline int bio_list_empty(const struct bio_list *bl)
586 : {
587 0 : return bl->head == NULL;
588 : }
589 :
590 12 : static inline void bio_list_init(struct bio_list *bl)
591 : {
592 12 : bl->head = bl->tail = NULL;
593 0 : }
594 :
595 : #define BIO_EMPTY_LIST { NULL, NULL }
596 :
597 : #define bio_list_for_each(bio, bl) \
598 : for (bio = (bl)->head; bio; bio = bio->bi_next)
599 :
600 : static inline unsigned bio_list_size(const struct bio_list *bl)
601 : {
602 : unsigned sz = 0;
603 : struct bio *bio;
604 :
605 : bio_list_for_each(bio, bl)
606 : sz++;
607 :
608 : return sz;
609 : }
610 :
611 0 : static inline void bio_list_add(struct bio_list *bl, struct bio *bio)
612 : {
613 0 : bio->bi_next = NULL;
614 :
615 0 : if (bl->tail)
616 0 : bl->tail->bi_next = bio;
617 : else
618 0 : bl->head = bio;
619 :
620 0 : bl->tail = bio;
621 0 : }
622 :
623 0 : static inline void bio_list_add_head(struct bio_list *bl, struct bio *bio)
624 : {
625 0 : bio->bi_next = bl->head;
626 :
627 0 : bl->head = bio;
628 :
629 0 : if (!bl->tail)
630 0 : bl->tail = bio;
631 : }
632 :
633 0 : static inline void bio_list_merge(struct bio_list *bl, struct bio_list *bl2)
634 : {
635 0 : if (!bl2->head)
636 : return;
637 :
638 0 : if (bl->tail)
639 0 : bl->tail->bi_next = bl2->head;
640 : else
641 0 : bl->head = bl2->head;
642 :
643 0 : bl->tail = bl2->tail;
644 : }
645 :
646 : static inline void bio_list_merge_head(struct bio_list *bl,
647 : struct bio_list *bl2)
648 : {
649 : if (!bl2->head)
650 : return;
651 :
652 : if (bl->head)
653 : bl2->tail->bi_next = bl->head;
654 : else
655 : bl->tail = bl2->tail;
656 :
657 : bl->head = bl2->head;
658 : }
659 :
660 : static inline struct bio *bio_list_peek(struct bio_list *bl)
661 : {
662 : return bl->head;
663 : }
664 :
665 8737 : static inline struct bio *bio_list_pop(struct bio_list *bl)
666 : {
667 8737 : struct bio *bio = bl->head;
668 :
669 8737 : if (bio) {
670 0 : bl->head = bl->head->bi_next;
671 0 : if (!bl->head)
672 0 : bl->tail = NULL;
673 :
674 0 : bio->bi_next = NULL;
675 : }
676 :
677 8737 : return bio;
678 : }
679 :
680 : static inline struct bio *bio_list_get(struct bio_list *bl)
681 : {
682 : struct bio *bio = bl->head;
683 :
684 : bl->head = bl->tail = NULL;
685 :
686 : return bio;
687 : }
688 :
689 : /*
690 : * Increment chain count for the bio. Make sure the CHAIN flag update
691 : * is visible before the raised count.
692 : */
693 0 : static inline void bio_inc_remaining(struct bio *bio)
694 : {
695 0 : bio_set_flag(bio, BIO_CHAIN);
696 0 : smp_mb__before_atomic();
697 0 : atomic_inc(&bio->__bi_remaining);
698 0 : }
699 :
700 : /*
701 : * bio_set is used to allow other portions of the IO system to
702 : * allocate their own private memory pools for bio and iovec structures.
703 : * These memory pools in turn all allocate from the bio_slab
704 : * and the bvec_slabs[].
705 : */
706 : #define BIO_POOL_SIZE 2
707 :
708 : struct bio_set {
709 : struct kmem_cache *bio_slab;
710 : unsigned int front_pad;
711 :
712 : mempool_t bio_pool;
713 : mempool_t bvec_pool;
714 : #if defined(CONFIG_BLK_DEV_INTEGRITY)
715 : mempool_t bio_integrity_pool;
716 : mempool_t bvec_integrity_pool;
717 : #endif
718 :
719 : unsigned int back_pad;
720 : /*
721 : * Deadlock avoidance for stacking block drivers: see comments in
722 : * bio_alloc_bioset() for details
723 : */
724 : spinlock_t rescue_lock;
725 : struct bio_list rescue_list;
726 : struct work_struct rescue_work;
727 : struct workqueue_struct *rescue_workqueue;
728 : };
729 :
730 0 : static inline bool bioset_initialized(struct bio_set *bs)
731 : {
732 0 : return bs->bio_slab != NULL;
733 : }
734 :
735 : #if defined(CONFIG_BLK_DEV_INTEGRITY)
736 :
737 : #define bip_for_each_vec(bvl, bip, iter) \
738 : for_each_bvec(bvl, (bip)->bip_vec, iter, (bip)->bip_iter)
739 :
740 : #define bio_for_each_integrity_vec(_bvl, _bio, _iter) \
741 : for_each_bio(_bio) \
742 : bip_for_each_vec(_bvl, _bio->bi_integrity, _iter)
743 :
744 : extern struct bio_integrity_payload *bio_integrity_alloc(struct bio *, gfp_t, unsigned int);
745 : extern int bio_integrity_add_page(struct bio *, struct page *, unsigned int, unsigned int);
746 : extern bool bio_integrity_prep(struct bio *);
747 : extern void bio_integrity_advance(struct bio *, unsigned int);
748 : extern void bio_integrity_trim(struct bio *);
749 : extern int bio_integrity_clone(struct bio *, struct bio *, gfp_t);
750 : extern int bioset_integrity_create(struct bio_set *, int);
751 : extern void bioset_integrity_free(struct bio_set *);
752 : extern void bio_integrity_init(void);
753 :
754 : #else /* CONFIG_BLK_DEV_INTEGRITY */
755 :
756 26204 : static inline void *bio_integrity(struct bio *bio)
757 : {
758 26204 : return NULL;
759 : }
760 :
761 1 : static inline int bioset_integrity_create(struct bio_set *bs, int pool_size)
762 : {
763 1 : return 0;
764 : }
765 :
766 0 : static inline void bioset_integrity_free (struct bio_set *bs)
767 : {
768 0 : return;
769 : }
770 :
771 8737 : static inline bool bio_integrity_prep(struct bio *bio)
772 : {
773 8737 : return true;
774 : }
775 :
776 : static inline int bio_integrity_clone(struct bio *bio, struct bio *bio_src,
777 : gfp_t gfp_mask)
778 : {
779 : return 0;
780 : }
781 :
782 : static inline void bio_integrity_advance(struct bio *bio,
783 : unsigned int bytes_done)
784 : {
785 : return;
786 : }
787 :
788 : static inline void bio_integrity_trim(struct bio *bio)
789 : {
790 : return;
791 : }
792 :
793 1 : static inline void bio_integrity_init(void)
794 : {
795 1 : return;
796 : }
797 :
798 0 : static inline bool bio_integrity_flagged(struct bio *bio, enum bip_flags flag)
799 : {
800 0 : return false;
801 : }
802 :
803 : static inline void *bio_integrity_alloc(struct bio * bio, gfp_t gfp,
804 : unsigned int nr)
805 : {
806 : return ERR_PTR(-EINVAL);
807 : }
808 :
809 : static inline int bio_integrity_add_page(struct bio *bio, struct page *page,
810 : unsigned int len, unsigned int offset)
811 : {
812 : return 0;
813 : }
814 :
815 : #endif /* CONFIG_BLK_DEV_INTEGRITY */
816 :
817 : /*
818 : * Mark a bio as polled. Note that for async polled IO, the caller must
819 : * expect -EWOULDBLOCK if we cannot allocate a request (or other resources).
820 : * We cannot block waiting for requests on polled IO, as those completions
821 : * must be found by the caller. This is different than IRQ driven IO, where
822 : * it's safe to wait for IO to complete.
823 : */
824 0 : static inline void bio_set_polled(struct bio *bio, struct kiocb *kiocb)
825 : {
826 0 : bio->bi_opf |= REQ_HIPRI;
827 0 : if (!is_sync_kiocb(kiocb))
828 0 : bio->bi_opf |= REQ_NOWAIT;
829 : }
830 :
831 : #endif /* __LINUX_BIO_H */
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