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/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 | |
15 | struct queue_limits; |
16 | |
17 | static inline unsigned int bio_max_segs(unsigned int nr_segs) |
18 | { |
19 | return min(nr_segs, BIO_MAX_VECS); |
20 | } |
21 | |
22 | #define bio_prio(bio) (bio)->bi_ioprio |
23 | #define bio_set_prio(bio, prio) ((bio)->bi_ioprio = prio) |
24 | |
25 | #define bio_iter_iovec(bio, iter) \ |
26 | bvec_iter_bvec((bio)->bi_io_vec, (iter)) |
27 | |
28 | #define bio_iter_page(bio, iter) \ |
29 | bvec_iter_page((bio)->bi_io_vec, (iter)) |
30 | #define bio_iter_len(bio, iter) \ |
31 | bvec_iter_len((bio)->bi_io_vec, (iter)) |
32 | #define bio_iter_offset(bio, iter) \ |
33 | bvec_iter_offset((bio)->bi_io_vec, (iter)) |
34 | |
35 | #define bio_page(bio) bio_iter_page((bio), (bio)->bi_iter) |
36 | #define bio_offset(bio) bio_iter_offset((bio), (bio)->bi_iter) |
37 | #define bio_iovec(bio) bio_iter_iovec((bio), (bio)->bi_iter) |
38 | |
39 | #define bvec_iter_sectors(iter) ((iter).bi_size >> 9) |
40 | #define bvec_iter_end_sector(iter) ((iter).bi_sector + bvec_iter_sectors((iter))) |
41 | |
42 | #define bio_sectors(bio) bvec_iter_sectors((bio)->bi_iter) |
43 | #define bio_end_sector(bio) bvec_iter_end_sector((bio)->bi_iter) |
44 | |
45 | /* |
46 | * Return the data direction, READ or WRITE. |
47 | */ |
48 | #define bio_data_dir(bio) \ |
49 | (op_is_write(bio_op(bio)) ? WRITE : READ) |
50 | |
51 | /* |
52 | * Check whether this bio carries any data or not. A NULL bio is allowed. |
53 | */ |
54 | static inline bool bio_has_data(struct bio *bio) |
55 | { |
56 | if (bio && |
57 | bio->bi_iter.bi_size && |
58 | bio_op(bio) != REQ_OP_DISCARD && |
59 | bio_op(bio) != REQ_OP_SECURE_ERASE && |
60 | bio_op(bio) != REQ_OP_WRITE_ZEROES) |
61 | return true; |
62 | |
63 | return false; |
64 | } |
65 | |
66 | static inline bool bio_no_advance_iter(const struct bio *bio) |
67 | { |
68 | return bio_op(bio) == REQ_OP_DISCARD || |
69 | bio_op(bio) == REQ_OP_SECURE_ERASE || |
70 | bio_op(bio) == REQ_OP_WRITE_ZEROES; |
71 | } |
72 | |
73 | static inline void *bio_data(struct bio *bio) |
74 | { |
75 | if (bio_has_data(bio)) |
76 | return page_address(bio_page(bio)) + bio_offset(bio); |
77 | |
78 | return NULL; |
79 | } |
80 | |
81 | static inline bool bio_next_segment(const struct bio *bio, |
82 | struct bvec_iter_all *iter) |
83 | { |
84 | if (iter->idx >= bio->bi_vcnt) |
85 | return false; |
86 | |
87 | bvec_advance(bvec: &bio->bi_io_vec[iter->idx], iter_all: iter); |
88 | return true; |
89 | } |
90 | |
91 | /* |
92 | * drivers should _never_ use the all version - the bio may have been split |
93 | * before it got to the driver and the driver won't own all of it |
94 | */ |
95 | #define bio_for_each_segment_all(bvl, bio, iter) \ |
96 | for (bvl = bvec_init_iter_all(&iter); bio_next_segment((bio), &iter); ) |
97 | |
98 | static inline void bio_advance_iter(const struct bio *bio, |
99 | struct bvec_iter *iter, unsigned int bytes) |
100 | { |
101 | iter->bi_sector += bytes >> 9; |
102 | |
103 | if (bio_no_advance_iter(bio)) |
104 | iter->bi_size -= bytes; |
105 | else |
106 | bvec_iter_advance(bv: bio->bi_io_vec, iter, bytes); |
107 | /* TODO: It is reasonable to complete bio with error here. */ |
108 | } |
109 | |
110 | /* @bytes should be less or equal to bvec[i->bi_idx].bv_len */ |
111 | static inline void bio_advance_iter_single(const struct bio *bio, |
112 | struct bvec_iter *iter, |
113 | unsigned int bytes) |
114 | { |
115 | iter->bi_sector += bytes >> 9; |
116 | |
117 | if (bio_no_advance_iter(bio)) |
118 | iter->bi_size -= bytes; |
119 | else |
120 | bvec_iter_advance_single(bv: bio->bi_io_vec, iter, bytes); |
121 | } |
122 | |
123 | void __bio_advance(struct bio *, unsigned bytes); |
124 | |
125 | /** |
126 | * bio_advance - increment/complete a bio by some number of bytes |
127 | * @bio: bio to advance |
128 | * @nbytes: number of bytes to complete |
129 | * |
130 | * This updates bi_sector, bi_size and bi_idx; if the number of bytes to |
131 | * complete doesn't align with a bvec boundary, then bv_len and bv_offset will |
132 | * be updated on the last bvec as well. |
133 | * |
134 | * @bio will then represent the remaining, uncompleted portion of the io. |
135 | */ |
136 | static inline void bio_advance(struct bio *bio, unsigned int nbytes) |
137 | { |
138 | if (nbytes == bio->bi_iter.bi_size) { |
139 | bio->bi_iter.bi_size = 0; |
140 | return; |
141 | } |
142 | __bio_advance(bio, bytes: nbytes); |
143 | } |
144 | |
145 | #define __bio_for_each_segment(bvl, bio, iter, start) \ |
146 | for (iter = (start); \ |
147 | (iter).bi_size && \ |
148 | ((bvl = bio_iter_iovec((bio), (iter))), 1); \ |
149 | bio_advance_iter_single((bio), &(iter), (bvl).bv_len)) |
150 | |
151 | #define bio_for_each_segment(bvl, bio, iter) \ |
152 | __bio_for_each_segment(bvl, bio, iter, (bio)->bi_iter) |
153 | |
154 | #define __bio_for_each_bvec(bvl, bio, iter, start) \ |
155 | for (iter = (start); \ |
156 | (iter).bi_size && \ |
157 | ((bvl = mp_bvec_iter_bvec((bio)->bi_io_vec, (iter))), 1); \ |
158 | bio_advance_iter_single((bio), &(iter), (bvl).bv_len)) |
159 | |
160 | /* iterate over multi-page bvec */ |
161 | #define bio_for_each_bvec(bvl, bio, iter) \ |
162 | __bio_for_each_bvec(bvl, bio, iter, (bio)->bi_iter) |
163 | |
164 | /* |
165 | * Iterate over all multi-page bvecs. Drivers shouldn't use this version for the |
166 | * same reasons as bio_for_each_segment_all(). |
167 | */ |
168 | #define bio_for_each_bvec_all(bvl, bio, i) \ |
169 | for (i = 0, bvl = bio_first_bvec_all(bio); \ |
170 | i < (bio)->bi_vcnt; i++, bvl++) |
171 | |
172 | #define bio_iter_last(bvec, iter) ((iter).bi_size == (bvec).bv_len) |
173 | |
174 | static inline unsigned bio_segments(struct bio *bio) |
175 | { |
176 | unsigned segs = 0; |
177 | struct bio_vec bv; |
178 | struct bvec_iter iter; |
179 | |
180 | /* |
181 | * We special case discard/write same/write zeroes, because they |
182 | * interpret bi_size differently: |
183 | */ |
184 | |
185 | switch (bio_op(bio)) { |
186 | case REQ_OP_DISCARD: |
187 | case REQ_OP_SECURE_ERASE: |
188 | case REQ_OP_WRITE_ZEROES: |
189 | return 0; |
190 | default: |
191 | break; |
192 | } |
193 | |
194 | bio_for_each_segment(bv, bio, iter) |
195 | segs++; |
196 | |
197 | return segs; |
198 | } |
199 | |
200 | /* |
201 | * get a reference to a bio, so it won't disappear. the intended use is |
202 | * something like: |
203 | * |
204 | * bio_get(bio); |
205 | * submit_bio(rw, bio); |
206 | * if (bio->bi_flags ...) |
207 | * do_something |
208 | * bio_put(bio); |
209 | * |
210 | * without the bio_get(), it could potentially complete I/O before submit_bio |
211 | * returns. and then bio would be freed memory when if (bio->bi_flags ...) |
212 | * runs |
213 | */ |
214 | static inline void bio_get(struct bio *bio) |
215 | { |
216 | bio->bi_flags |= (1 << BIO_REFFED); |
217 | smp_mb__before_atomic(); |
218 | atomic_inc(v: &bio->__bi_cnt); |
219 | } |
220 | |
221 | static inline void bio_cnt_set(struct bio *bio, unsigned int count) |
222 | { |
223 | if (count != 1) { |
224 | bio->bi_flags |= (1 << BIO_REFFED); |
225 | smp_mb(); |
226 | } |
227 | atomic_set(v: &bio->__bi_cnt, i: count); |
228 | } |
229 | |
230 | static inline bool bio_flagged(struct bio *bio, unsigned int bit) |
231 | { |
232 | return bio->bi_flags & (1U << bit); |
233 | } |
234 | |
235 | static inline void bio_set_flag(struct bio *bio, unsigned int bit) |
236 | { |
237 | bio->bi_flags |= (1U << bit); |
238 | } |
239 | |
240 | static inline void bio_clear_flag(struct bio *bio, unsigned int bit) |
241 | { |
242 | bio->bi_flags &= ~(1U << bit); |
243 | } |
244 | |
245 | static inline struct bio_vec *bio_first_bvec_all(struct bio *bio) |
246 | { |
247 | WARN_ON_ONCE(bio_flagged(bio, BIO_CLONED)); |
248 | return bio->bi_io_vec; |
249 | } |
250 | |
251 | static inline struct page *bio_first_page_all(struct bio *bio) |
252 | { |
253 | return bio_first_bvec_all(bio)->bv_page; |
254 | } |
255 | |
256 | static inline struct folio *bio_first_folio_all(struct bio *bio) |
257 | { |
258 | return page_folio(bio_first_page_all(bio)); |
259 | } |
260 | |
261 | static inline struct bio_vec *bio_last_bvec_all(struct bio *bio) |
262 | { |
263 | WARN_ON_ONCE(bio_flagged(bio, BIO_CLONED)); |
264 | return &bio->bi_io_vec[bio->bi_vcnt - 1]; |
265 | } |
266 | |
267 | /** |
268 | * struct folio_iter - State for iterating all folios in a bio. |
269 | * @folio: The current folio we're iterating. NULL after the last folio. |
270 | * @offset: The byte offset within the current folio. |
271 | * @length: The number of bytes in this iteration (will not cross folio |
272 | * boundary). |
273 | */ |
274 | struct folio_iter { |
275 | struct folio *folio; |
276 | size_t offset; |
277 | size_t length; |
278 | /* private: for use by the iterator */ |
279 | struct folio *_next; |
280 | size_t _seg_count; |
281 | int _i; |
282 | }; |
283 | |
284 | static inline void bio_first_folio(struct folio_iter *fi, struct bio *bio, |
285 | int i) |
286 | { |
287 | struct bio_vec *bvec = bio_first_bvec_all(bio) + i; |
288 | |
289 | fi->folio = page_folio(bvec->bv_page); |
290 | fi->offset = bvec->bv_offset + |
291 | PAGE_SIZE * (bvec->bv_page - &fi->folio->page); |
292 | fi->_seg_count = bvec->bv_len; |
293 | fi->length = min(folio_size(fi->folio) - fi->offset, fi->_seg_count); |
294 | fi->_next = folio_next(folio: fi->folio); |
295 | fi->_i = i; |
296 | } |
297 | |
298 | static inline void bio_next_folio(struct folio_iter *fi, struct bio *bio) |
299 | { |
300 | fi->_seg_count -= fi->length; |
301 | if (fi->_seg_count) { |
302 | fi->folio = fi->_next; |
303 | fi->offset = 0; |
304 | fi->length = min(folio_size(fi->folio), fi->_seg_count); |
305 | fi->_next = folio_next(folio: fi->folio); |
306 | } else if (fi->_i + 1 < bio->bi_vcnt) { |
307 | bio_first_folio(fi, bio, i: fi->_i + 1); |
308 | } else { |
309 | fi->folio = NULL; |
310 | } |
311 | } |
312 | |
313 | /** |
314 | * bio_for_each_folio_all - Iterate over each folio in a bio. |
315 | * @fi: struct folio_iter which is updated for each folio. |
316 | * @bio: struct bio to iterate over. |
317 | */ |
318 | #define bio_for_each_folio_all(fi, bio) \ |
319 | for (bio_first_folio(&fi, bio, 0); fi.folio; bio_next_folio(&fi, bio)) |
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 | void bio_trim(struct bio *bio, sector_t offset, sector_t size); |
383 | extern struct bio *bio_split(struct bio *bio, int sectors, |
384 | gfp_t gfp, struct bio_set *bs); |
385 | struct bio *bio_split_rw(struct bio *bio, const struct queue_limits *lim, |
386 | unsigned *segs, struct bio_set *bs, unsigned max_bytes); |
387 | |
388 | /** |
389 | * bio_next_split - get next @sectors from a bio, splitting if necessary |
390 | * @bio: bio to split |
391 | * @sectors: number of sectors to split from the front of @bio |
392 | * @gfp: gfp mask |
393 | * @bs: bio set to allocate from |
394 | * |
395 | * Return: a bio representing the next @sectors of @bio - if the bio is smaller |
396 | * than @sectors, returns the original bio unchanged. |
397 | */ |
398 | static inline struct bio *bio_next_split(struct bio *bio, int sectors, |
399 | gfp_t gfp, struct bio_set *bs) |
400 | { |
401 | if (sectors >= bio_sectors(bio)) |
402 | return bio; |
403 | |
404 | return bio_split(bio, sectors, gfp, bs); |
405 | } |
406 | |
407 | enum { |
408 | BIOSET_NEED_BVECS = BIT(0), |
409 | BIOSET_NEED_RESCUER = BIT(1), |
410 | BIOSET_PERCPU_CACHE = BIT(2), |
411 | }; |
412 | extern int bioset_init(struct bio_set *, unsigned int, unsigned int, int flags); |
413 | extern void bioset_exit(struct bio_set *); |
414 | extern int biovec_init_pool(mempool_t *pool, int pool_entries); |
415 | |
416 | struct bio *bio_alloc_bioset(struct block_device *bdev, unsigned short nr_vecs, |
417 | blk_opf_t opf, gfp_t gfp_mask, |
418 | struct bio_set *bs); |
419 | struct bio *bio_kmalloc(unsigned short nr_vecs, gfp_t gfp_mask); |
420 | extern void bio_put(struct bio *); |
421 | |
422 | struct bio *bio_alloc_clone(struct block_device *bdev, struct bio *bio_src, |
423 | gfp_t gfp, struct bio_set *bs); |
424 | int bio_init_clone(struct block_device *bdev, struct bio *bio, |
425 | struct bio *bio_src, gfp_t gfp); |
426 | |
427 | extern struct bio_set fs_bio_set; |
428 | |
429 | static inline struct bio *bio_alloc(struct block_device *bdev, |
430 | unsigned short nr_vecs, blk_opf_t opf, gfp_t gfp_mask) |
431 | { |
432 | return bio_alloc_bioset(bdev, nr_vecs, opf, gfp_mask, bs: &fs_bio_set); |
433 | } |
434 | |
435 | void submit_bio(struct bio *bio); |
436 | |
437 | extern void bio_endio(struct bio *); |
438 | |
439 | static inline void bio_io_error(struct bio *bio) |
440 | { |
441 | bio->bi_status = BLK_STS_IOERR; |
442 | bio_endio(bio); |
443 | } |
444 | |
445 | static inline void bio_wouldblock_error(struct bio *bio) |
446 | { |
447 | bio_set_flag(bio, bit: BIO_QUIET); |
448 | bio->bi_status = BLK_STS_AGAIN; |
449 | bio_endio(bio); |
450 | } |
451 | |
452 | /* |
453 | * Calculate number of bvec segments that should be allocated to fit data |
454 | * pointed by @iter. If @iter is backed by bvec it's going to be reused |
455 | * instead of allocating a new one. |
456 | */ |
457 | static inline int bio_iov_vecs_to_alloc(struct iov_iter *iter, int max_segs) |
458 | { |
459 | if (iov_iter_is_bvec(i: iter)) |
460 | return 0; |
461 | return iov_iter_npages(i: iter, maxpages: max_segs); |
462 | } |
463 | |
464 | struct request_queue; |
465 | |
466 | extern int submit_bio_wait(struct bio *bio); |
467 | void bio_init(struct bio *bio, struct block_device *bdev, struct bio_vec *table, |
468 | unsigned short max_vecs, blk_opf_t opf); |
469 | extern void bio_uninit(struct bio *); |
470 | void bio_reset(struct bio *bio, struct block_device *bdev, blk_opf_t opf); |
471 | void bio_chain(struct bio *, struct bio *); |
472 | |
473 | int __must_check bio_add_page(struct bio *bio, struct page *page, unsigned len, |
474 | unsigned off); |
475 | bool __must_check bio_add_folio(struct bio *bio, struct folio *folio, |
476 | size_t len, size_t off); |
477 | extern int bio_add_pc_page(struct request_queue *, struct bio *, struct page *, |
478 | unsigned int, unsigned int); |
479 | int bio_add_zone_append_page(struct bio *bio, struct page *page, |
480 | unsigned int len, unsigned int offset); |
481 | void __bio_add_page(struct bio *bio, struct page *page, |
482 | unsigned int len, unsigned int off); |
483 | void bio_add_folio_nofail(struct bio *bio, struct folio *folio, size_t len, |
484 | size_t off); |
485 | int bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter); |
486 | void bio_iov_bvec_set(struct bio *bio, struct iov_iter *iter); |
487 | void __bio_release_pages(struct bio *bio, bool mark_dirty); |
488 | extern void bio_set_pages_dirty(struct bio *bio); |
489 | extern void bio_check_pages_dirty(struct bio *bio); |
490 | |
491 | extern void bio_copy_data_iter(struct bio *dst, struct bvec_iter *dst_iter, |
492 | struct bio *src, struct bvec_iter *src_iter); |
493 | extern void bio_copy_data(struct bio *dst, struct bio *src); |
494 | extern void bio_free_pages(struct bio *bio); |
495 | void guard_bio_eod(struct bio *bio); |
496 | void zero_fill_bio_iter(struct bio *bio, struct bvec_iter iter); |
497 | |
498 | static inline void zero_fill_bio(struct bio *bio) |
499 | { |
500 | zero_fill_bio_iter(bio, iter: bio->bi_iter); |
501 | } |
502 | |
503 | static inline void bio_release_pages(struct bio *bio, bool mark_dirty) |
504 | { |
505 | if (bio_flagged(bio, bit: BIO_PAGE_PINNED)) |
506 | __bio_release_pages(bio, mark_dirty); |
507 | } |
508 | |
509 | #define bio_dev(bio) \ |
510 | disk_devt((bio)->bi_bdev->bd_disk) |
511 | |
512 | #ifdef CONFIG_BLK_CGROUP |
513 | void bio_associate_blkg(struct bio *bio); |
514 | void bio_associate_blkg_from_css(struct bio *bio, |
515 | struct cgroup_subsys_state *css); |
516 | void bio_clone_blkg_association(struct bio *dst, struct bio *src); |
517 | void blkcg_punt_bio_submit(struct bio *bio); |
518 | #else /* CONFIG_BLK_CGROUP */ |
519 | static inline void bio_associate_blkg(struct bio *bio) { } |
520 | static inline void bio_associate_blkg_from_css(struct bio *bio, |
521 | struct cgroup_subsys_state *css) |
522 | { } |
523 | static inline void bio_clone_blkg_association(struct bio *dst, |
524 | struct bio *src) { } |
525 | static inline void blkcg_punt_bio_submit(struct bio *bio) |
526 | { |
527 | submit_bio(bio); |
528 | } |
529 | #endif /* CONFIG_BLK_CGROUP */ |
530 | |
531 | static inline void bio_set_dev(struct bio *bio, struct block_device *bdev) |
532 | { |
533 | bio_clear_flag(bio, bit: BIO_REMAPPED); |
534 | if (bio->bi_bdev != bdev) |
535 | bio_clear_flag(bio, bit: BIO_BPS_THROTTLED); |
536 | bio->bi_bdev = bdev; |
537 | bio_associate_blkg(bio); |
538 | } |
539 | |
540 | /* |
541 | * BIO list management for use by remapping drivers (e.g. DM or MD) and loop. |
542 | * |
543 | * A bio_list anchors a singly-linked list of bios chained through the bi_next |
544 | * member of the bio. The bio_list also caches the last list member to allow |
545 | * fast access to the tail. |
546 | */ |
547 | struct bio_list { |
548 | struct bio *head; |
549 | struct bio *tail; |
550 | }; |
551 | |
552 | static inline int bio_list_empty(const struct bio_list *bl) |
553 | { |
554 | return bl->head == NULL; |
555 | } |
556 | |
557 | static inline void bio_list_init(struct bio_list *bl) |
558 | { |
559 | bl->head = bl->tail = NULL; |
560 | } |
561 | |
562 | #define BIO_EMPTY_LIST { NULL, NULL } |
563 | |
564 | #define bio_list_for_each(bio, bl) \ |
565 | for (bio = (bl)->head; bio; bio = bio->bi_next) |
566 | |
567 | static inline unsigned bio_list_size(const struct bio_list *bl) |
568 | { |
569 | unsigned sz = 0; |
570 | struct bio *bio; |
571 | |
572 | bio_list_for_each(bio, bl) |
573 | sz++; |
574 | |
575 | return sz; |
576 | } |
577 | |
578 | static inline void bio_list_add(struct bio_list *bl, struct bio *bio) |
579 | { |
580 | bio->bi_next = NULL; |
581 | |
582 | if (bl->tail) |
583 | bl->tail->bi_next = bio; |
584 | else |
585 | bl->head = bio; |
586 | |
587 | bl->tail = bio; |
588 | } |
589 | |
590 | static inline void bio_list_add_head(struct bio_list *bl, struct bio *bio) |
591 | { |
592 | bio->bi_next = bl->head; |
593 | |
594 | bl->head = bio; |
595 | |
596 | if (!bl->tail) |
597 | bl->tail = bio; |
598 | } |
599 | |
600 | static inline void bio_list_merge(struct bio_list *bl, struct bio_list *bl2) |
601 | { |
602 | if (!bl2->head) |
603 | return; |
604 | |
605 | if (bl->tail) |
606 | bl->tail->bi_next = bl2->head; |
607 | else |
608 | bl->head = bl2->head; |
609 | |
610 | bl->tail = bl2->tail; |
611 | } |
612 | |
613 | static inline void bio_list_merge_head(struct bio_list *bl, |
614 | struct bio_list *bl2) |
615 | { |
616 | if (!bl2->head) |
617 | return; |
618 | |
619 | if (bl->head) |
620 | bl2->tail->bi_next = bl->head; |
621 | else |
622 | bl->tail = bl2->tail; |
623 | |
624 | bl->head = bl2->head; |
625 | } |
626 | |
627 | static inline struct bio *bio_list_peek(struct bio_list *bl) |
628 | { |
629 | return bl->head; |
630 | } |
631 | |
632 | static inline struct bio *bio_list_pop(struct bio_list *bl) |
633 | { |
634 | struct bio *bio = bl->head; |
635 | |
636 | if (bio) { |
637 | bl->head = bl->head->bi_next; |
638 | if (!bl->head) |
639 | bl->tail = NULL; |
640 | |
641 | bio->bi_next = NULL; |
642 | } |
643 | |
644 | return bio; |
645 | } |
646 | |
647 | static inline struct bio *bio_list_get(struct bio_list *bl) |
648 | { |
649 | struct bio *bio = bl->head; |
650 | |
651 | bl->head = bl->tail = NULL; |
652 | |
653 | return bio; |
654 | } |
655 | |
656 | /* |
657 | * Increment chain count for the bio. Make sure the CHAIN flag update |
658 | * is visible before the raised count. |
659 | */ |
660 | static inline void bio_inc_remaining(struct bio *bio) |
661 | { |
662 | bio_set_flag(bio, bit: BIO_CHAIN); |
663 | smp_mb__before_atomic(); |
664 | atomic_inc(v: &bio->__bi_remaining); |
665 | } |
666 | |
667 | /* |
668 | * bio_set is used to allow other portions of the IO system to |
669 | * allocate their own private memory pools for bio and iovec structures. |
670 | * These memory pools in turn all allocate from the bio_slab |
671 | * and the bvec_slabs[]. |
672 | */ |
673 | #define BIO_POOL_SIZE 2 |
674 | |
675 | struct bio_set { |
676 | struct kmem_cache *bio_slab; |
677 | unsigned int front_pad; |
678 | |
679 | /* |
680 | * per-cpu bio alloc cache |
681 | */ |
682 | struct bio_alloc_cache __percpu *cache; |
683 | |
684 | mempool_t bio_pool; |
685 | mempool_t bvec_pool; |
686 | #if defined(CONFIG_BLK_DEV_INTEGRITY) |
687 | mempool_t bio_integrity_pool; |
688 | mempool_t bvec_integrity_pool; |
689 | #endif |
690 | |
691 | unsigned int back_pad; |
692 | /* |
693 | * Deadlock avoidance for stacking block drivers: see comments in |
694 | * bio_alloc_bioset() for details |
695 | */ |
696 | spinlock_t rescue_lock; |
697 | struct bio_list rescue_list; |
698 | struct work_struct rescue_work; |
699 | struct workqueue_struct *rescue_workqueue; |
700 | |
701 | /* |
702 | * Hot un-plug notifier for the per-cpu cache, if used |
703 | */ |
704 | struct hlist_node cpuhp_dead; |
705 | }; |
706 | |
707 | static inline bool bioset_initialized(struct bio_set *bs) |
708 | { |
709 | return bs->bio_slab != NULL; |
710 | } |
711 | |
712 | #if defined(CONFIG_BLK_DEV_INTEGRITY) |
713 | |
714 | #define bip_for_each_vec(bvl, bip, iter) \ |
715 | for_each_bvec(bvl, (bip)->bip_vec, iter, (bip)->bip_iter) |
716 | |
717 | #define bio_for_each_integrity_vec(_bvl, _bio, _iter) \ |
718 | for_each_bio(_bio) \ |
719 | bip_for_each_vec(_bvl, _bio->bi_integrity, _iter) |
720 | |
721 | extern struct bio_integrity_payload *bio_integrity_alloc(struct bio *, gfp_t, unsigned int); |
722 | extern int bio_integrity_add_page(struct bio *, struct page *, unsigned int, unsigned int); |
723 | extern bool bio_integrity_prep(struct bio *); |
724 | extern void bio_integrity_advance(struct bio *, unsigned int); |
725 | extern void bio_integrity_trim(struct bio *); |
726 | extern int bio_integrity_clone(struct bio *, struct bio *, gfp_t); |
727 | extern int bioset_integrity_create(struct bio_set *, int); |
728 | extern void bioset_integrity_free(struct bio_set *); |
729 | extern void bio_integrity_init(void); |
730 | |
731 | #else /* CONFIG_BLK_DEV_INTEGRITY */ |
732 | |
733 | static inline void *bio_integrity(struct bio *bio) |
734 | { |
735 | return NULL; |
736 | } |
737 | |
738 | static inline int bioset_integrity_create(struct bio_set *bs, int pool_size) |
739 | { |
740 | return 0; |
741 | } |
742 | |
743 | static inline void bioset_integrity_free (struct bio_set *bs) |
744 | { |
745 | return; |
746 | } |
747 | |
748 | static inline bool bio_integrity_prep(struct bio *bio) |
749 | { |
750 | return true; |
751 | } |
752 | |
753 | static inline int bio_integrity_clone(struct bio *bio, struct bio *bio_src, |
754 | gfp_t gfp_mask) |
755 | { |
756 | return 0; |
757 | } |
758 | |
759 | static inline void bio_integrity_advance(struct bio *bio, |
760 | unsigned int bytes_done) |
761 | { |
762 | return; |
763 | } |
764 | |
765 | static inline void bio_integrity_trim(struct bio *bio) |
766 | { |
767 | return; |
768 | } |
769 | |
770 | static inline void bio_integrity_init(void) |
771 | { |
772 | return; |
773 | } |
774 | |
775 | static inline bool bio_integrity_flagged(struct bio *bio, enum bip_flags flag) |
776 | { |
777 | return false; |
778 | } |
779 | |
780 | static inline void *bio_integrity_alloc(struct bio * bio, gfp_t gfp, |
781 | unsigned int nr) |
782 | { |
783 | return ERR_PTR(-EINVAL); |
784 | } |
785 | |
786 | static inline int bio_integrity_add_page(struct bio *bio, struct page *page, |
787 | unsigned int len, unsigned int offset) |
788 | { |
789 | return 0; |
790 | } |
791 | |
792 | #endif /* CONFIG_BLK_DEV_INTEGRITY */ |
793 | |
794 | /* |
795 | * Mark a bio as polled. Note that for async polled IO, the caller must |
796 | * expect -EWOULDBLOCK if we cannot allocate a request (or other resources). |
797 | * We cannot block waiting for requests on polled IO, as those completions |
798 | * must be found by the caller. This is different than IRQ driven IO, where |
799 | * it's safe to wait for IO to complete. |
800 | */ |
801 | static inline void bio_set_polled(struct bio *bio, struct kiocb *kiocb) |
802 | { |
803 | bio->bi_opf |= REQ_POLLED; |
804 | if (kiocb->ki_flags & IOCB_NOWAIT) |
805 | bio->bi_opf |= REQ_NOWAIT; |
806 | } |
807 | |
808 | static inline void bio_clear_polled(struct bio *bio) |
809 | { |
810 | bio->bi_opf &= ~REQ_POLLED; |
811 | } |
812 | |
813 | struct bio *blk_next_bio(struct bio *bio, struct block_device *bdev, |
814 | unsigned int nr_pages, blk_opf_t opf, gfp_t gfp); |
815 | |
816 | #endif /* __LINUX_BIO_H */ |
817 | |