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block: introduce multi-page bvec helpers
[linux-block.git] / include / linux / bio.h
CommitLineData
1da177e4 1/*
1da177e4
LT		 2 * Copyright (C) 2001 Jens Axboe <axboe@suse.de>
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License version 2 as
6 * published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
7cc01581 10 *
1da177e4
LT		 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public Licens
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-
17 */
18#ifndef __LINUX_BIO_H
19#define __LINUX_BIO_H
20
21#include <linux/highmem.h>
22#include <linux/mempool.h>
22e2c507 23#include <linux/ioprio.h>
1da177e4 24
02a5e0ac 25#ifdef CONFIG_BLOCK
7cc01581
TH		 26/* struct bio, bio_vec and BIO_* flags are defined in blk_types.h */
27#include <linux/blk_types.h>
28
1da177e4
LT		 29#define BIO_DEBUG
30
31#ifdef BIO_DEBUG
32#define BIO_BUG_ON BUG_ON
33#else
34#define BIO_BUG_ON
35#endif
36
225311a4
HY		 37#ifdef CONFIG_THP_SWAP
38#if HPAGE_PMD_NR > 256
39#define BIO_MAX_PAGES HPAGE_PMD_NR
40#else
d84a8477 41#define BIO_MAX_PAGES 256
225311a4
HY		 42#endif
43#else
44#define BIO_MAX_PAGES 256
45#endif
1da177e4 46
43b62ce3
MC		 47#define bio_prio(bio) (bio)->bi_ioprio
48#define bio_set_prio(bio, prio) ((bio)->bi_ioprio = prio)
22e2c507 49
4550dd6c
KO		 50#define bio_iter_iovec(bio, iter) \
51 bvec_iter_bvec((bio)->bi_io_vec, (iter))
52
53#define bio_iter_page(bio, iter) \
54 bvec_iter_page((bio)->bi_io_vec, (iter))
55#define bio_iter_len(bio, iter) \
56 bvec_iter_len((bio)->bi_io_vec, (iter))
57#define bio_iter_offset(bio, iter) \
58 bvec_iter_offset((bio)->bi_io_vec, (iter))
59
60#define bio_page(bio) bio_iter_page((bio), (bio)->bi_iter)
61#define bio_offset(bio) bio_iter_offset((bio), (bio)->bi_iter)
62#define bio_iovec(bio) bio_iter_iovec((bio), (bio)->bi_iter)
7988613b 63
458b76ed
KO		 64#define bio_multiple_segments(bio) \
65 ((bio)->bi_iter.bi_size != bio_iovec(bio).bv_len)
38a72dac
KO		 66
67#define bvec_iter_sectors(iter) ((iter).bi_size >> 9)
68#define bvec_iter_end_sector(iter) ((iter).bi_sector + bvec_iter_sectors((iter)))
69
70#define bio_sectors(bio) bvec_iter_sectors((bio)->bi_iter)
71#define bio_end_sector(bio) bvec_iter_end_sector((bio)->bi_iter)
bf2de6f5 72
d3849953
CH		 73/*
74 * Return the data direction, READ or WRITE.
75 */
76#define bio_data_dir(bio) \
77 (op_is_write(bio_op(bio)) ? WRITE : READ)
78
458b76ed
KO		 79/*
80 * Check whether this bio carries any data or not. A NULL bio is allowed.
81 */
82static inline bool bio_has_data(struct bio *bio)
83{
84 if (bio &&
85 bio->bi_iter.bi_size &&
7afafc8a 86 bio_op(bio) != REQ_OP_DISCARD &&
a6f0788e
CK		 87 bio_op(bio) != REQ_OP_SECURE_ERASE &&
88 bio_op(bio) != REQ_OP_WRITE_ZEROES)
458b76ed
KO		 89 return true;
90
91 return false;
92}
93
95fe6c1a
MC		 94static inline bool bio_no_advance_iter(struct bio *bio)
95{
7afafc8a
AH		 96 return bio_op(bio) == REQ_OP_DISCARD ||
97 bio_op(bio) == REQ_OP_SECURE_ERASE ||
a6f0788e
CK		 98 bio_op(bio) == REQ_OP_WRITE_SAME ||
99 bio_op(bio) == REQ_OP_WRITE_ZEROES;
95fe6c1a
MC		 100}
101
458b76ed
KO		 102static inline bool bio_mergeable(struct bio *bio)
103{
1eff9d32 104 if (bio->bi_opf & REQ_NOMERGE_FLAGS)
458b76ed
KO		 105 return false;
106
107 return true;
108}
109
2e46e8b2 110static inline unsigned int bio_cur_bytes(struct bio *bio)
bf2de6f5 111{
458b76ed 112 if (bio_has_data(bio))
a4ad39b1 113 return bio_iovec(bio).bv_len;
fb2dce86 114 else /* dataless requests such as discard */
4f024f37 115 return bio->bi_iter.bi_size;
bf2de6f5
JA		 116}
117
118static inline void *bio_data(struct bio *bio)
119{
458b76ed 120 if (bio_has_data(bio))
bf2de6f5
JA		 121 return page_address(bio_page(bio)) + bio_offset(bio);
122
123 return NULL;
124}
1da177e4 125
0aa69fd3
CH		 126static inline bool bio_full(struct bio *bio)
127{
128 return bio->bi_vcnt >= bio->bi_max_vecs;
129}
130
d74c6d51
KO		 131/*
132 * drivers should _never_ use the all version - the bio may have been split
133 * before it got to the driver and the driver won't own all of it
134 */
135#define bio_for_each_segment_all(bvl, bio, i) \
f619d254 136 for (i = 0, bvl = (bio)->bi_io_vec; i < (bio)->bi_vcnt; i++, bvl++)
d74c6d51 137
4550dd6c
KO		 138static inline void bio_advance_iter(struct bio *bio, struct bvec_iter *iter,
139 unsigned bytes)
140{
141 iter->bi_sector += bytes >> 9;
142
7759eb23 143 if (bio_no_advance_iter(bio))
4550dd6c 144 iter->bi_size -= bytes;
7759eb23 145 else
4550dd6c 146 bvec_iter_advance(bio->bi_io_vec, iter, bytes);
b1fb2c52 147 /* TODO: It is reasonable to complete bio with error here. */
f9df1cd9
DM		 148}
149
7988613b
KO		 150#define __bio_for_each_segment(bvl, bio, iter, start) \
151 for (iter = (start); \
4550dd6c
KO		 152 (iter).bi_size && \
153 ((bvl = bio_iter_iovec((bio), (iter))), 1); \
154 bio_advance_iter((bio), &(iter), (bvl).bv_len))
7988613b
KO		 155
156#define bio_for_each_segment(bvl, bio, iter) \
157 __bio_for_each_segment(bvl, bio, iter, (bio)->bi_iter)
158
4550dd6c 159#define bio_iter_last(bvec, iter) ((iter).bi_size == (bvec).bv_len)
1da177e4 160
f4595875 161static inline unsigned bio_segments(struct bio *bio)
458b76ed
KO		 162{
163 unsigned segs = 0;
164 struct bio_vec bv;
165 struct bvec_iter iter;
166
8423ae3d 167 /*
a6f0788e
CK		 168 * We special case discard/write same/write zeroes, because they
169 * interpret bi_size differently:
8423ae3d
KO		 170 */
171
a6f0788e
CK		 172 switch (bio_op(bio)) {
173 case REQ_OP_DISCARD:
174 case REQ_OP_SECURE_ERASE:
a6f0788e 175 case REQ_OP_WRITE_ZEROES:
f9d03f96
CH		 176 return 0;
177 case REQ_OP_WRITE_SAME:
8423ae3d 178 return 1;
a6f0788e
CK		 179 default:
180 break;
181 }
8423ae3d 182
f4595875 183 bio_for_each_segment(bv, bio, iter)
458b76ed
KO		 184 segs++;
185
186 return segs;
187}
188
1da177e4
LT		 189/*
190 * get a reference to a bio, so it won't disappear. the intended use is
191 * something like:
192 *
193 * bio_get(bio);
194 * submit_bio(rw, bio);
195 * if (bio->bi_flags ...)
196 * do_something
197 * bio_put(bio);
198 *
199 * without the bio_get(), it could potentially complete I/O before submit_bio
200 * returns. and then bio would be freed memory when if (bio->bi_flags ...)
201 * runs
202 */
dac56212
JA		 203static inline void bio_get(struct bio *bio)
204{
205 bio->bi_flags |= (1 << BIO_REFFED);
206 smp_mb__before_atomic();
207 atomic_inc(&bio->__bi_cnt);
208}
209
210static inline void bio_cnt_set(struct bio *bio, unsigned int count)
211{
212 if (count != 1) {
213 bio->bi_flags |= (1 << BIO_REFFED);
214 smp_mb__before_atomic();
215 }
216 atomic_set(&bio->__bi_cnt, count);
217}
1da177e4 218
b7c44ed9
JA		 219static inline bool bio_flagged(struct bio *bio, unsigned int bit)
220{
2c68f6dc 221 return (bio->bi_flags & (1U << bit)) != 0;
b7c44ed9
JA		 222}
223
224static inline void bio_set_flag(struct bio *bio, unsigned int bit)
225{
2c68f6dc 226 bio->bi_flags |= (1U << bit);
b7c44ed9
JA		 227}
228
229static inline void bio_clear_flag(struct bio *bio, unsigned int bit)
230{
2c68f6dc 231 bio->bi_flags &= ~(1U << bit);
b7c44ed9
JA		 232}
233
7bcd79ac
ML		 234static inline void bio_get_first_bvec(struct bio *bio, struct bio_vec *bv)
235{
236 *bv = bio_iovec(bio);
237}
238
239static inline void bio_get_last_bvec(struct bio *bio, struct bio_vec *bv)
240{
241 struct bvec_iter iter = bio->bi_iter;
242 int idx;
243
7bcd79ac
ML		 244 if (unlikely(!bio_multiple_segments(bio))) {
245 *bv = bio_iovec(bio);
246 return;
247 }
248
249 bio_advance_iter(bio, &iter, iter.bi_size);
250
251 if (!iter.bi_bvec_done)
252 idx = iter.bi_idx - 1;
253 else /* in the middle of bvec */
254 idx = iter.bi_idx;
255
256 *bv = bio->bi_io_vec[idx];
257
258 /*
259 * iter.bi_bvec_done records actual length of the last bvec
260 * if this bio ends in the middle of one io vector
261 */
262 if (iter.bi_bvec_done)
263 bv->bv_len = iter.bi_bvec_done;
264}
265
86292abc
ML		 266static inline struct bio_vec *bio_first_bvec_all(struct bio *bio)
267{
268 WARN_ON_ONCE(bio_flagged(bio, BIO_CLONED));
269 return bio->bi_io_vec;
270}
271
272static inline struct page *bio_first_page_all(struct bio *bio)
273{
274 return bio_first_bvec_all(bio)->bv_page;
275}
276
277static inline struct bio_vec *bio_last_bvec_all(struct bio *bio)
278{
279 WARN_ON_ONCE(bio_flagged(bio, BIO_CLONED));
280 return &bio->bi_io_vec[bio->bi_vcnt - 1];
281}
282
c611529e
MP		 283enum bip_flags {
284 BIP_BLOCK_INTEGRITY = 1 << 0, /* block layer owns integrity data */
285 BIP_MAPPED_INTEGRITY = 1 << 1, /* ref tag has been remapped */
286 BIP_CTRL_NOCHECK = 1 << 2, /* disable HBA integrity checking */
287 BIP_DISK_NOCHECK = 1 << 3, /* disable disk integrity checking */
288 BIP_IP_CHECKSUM = 1 << 4, /* IP checksum */
289};
290
7ba1ba12
MP		 291/*
292 * bio integrity payload
293 */
294struct bio_integrity_payload {
295 struct bio *bip_bio; /* parent bio */
7ba1ba12 296
d57a5f7c 297 struct bvec_iter bip_iter;
7ba1ba12 298
7878cba9 299 unsigned short bip_slab; /* slab the bip came from */
7ba1ba12 300 unsigned short bip_vcnt; /* # of integrity bio_vecs */
cbcd1054 301 unsigned short bip_max_vcnt; /* integrity bio_vec slots */
b1f01388 302 unsigned short bip_flags; /* control flags */
7ba1ba12 303
7759eb23
ML		 304 struct bvec_iter bio_iter; /* for rewinding parent bio */
305
7ba1ba12 306 struct work_struct bip_work; /* I/O completion */
6fda981c
KO		 307
308 struct bio_vec *bip_vec;
309 struct bio_vec bip_inline_vecs[0];/* embedded bvec array */
7ba1ba12 310};
18593088 311
06c1e390
KB		 312#if defined(CONFIG_BLK_DEV_INTEGRITY)
313
314static inline struct bio_integrity_payload *bio_integrity(struct bio *bio)
315{
1eff9d32 316 if (bio->bi_opf & REQ_INTEGRITY)
06c1e390
KB		 317 return bio->bi_integrity;
318
319 return NULL;
320}
321
c611529e
MP		 322static inline bool bio_integrity_flagged(struct bio *bio, enum bip_flags flag)
323{
324 struct bio_integrity_payload *bip = bio_integrity(bio);
325
326 if (bip)
327 return bip->bip_flags & flag;
328
329 return false;
330}
b1f01388 331
18593088
MP		 332static inline sector_t bip_get_seed(struct bio_integrity_payload *bip)
333{
334 return bip->bip_iter.bi_sector;
335}
336
337static inline void bip_set_seed(struct bio_integrity_payload *bip,
338 sector_t seed)
339{
340 bip->bip_iter.bi_sector = seed;
341}
342
7ba1ba12 343#endif /* CONFIG_BLK_DEV_INTEGRITY */
1da177e4 344
6678d83f 345extern void bio_trim(struct bio *bio, int offset, int size);
20d0189b
KO		 346extern struct bio *bio_split(struct bio *bio, int sectors,
347 gfp_t gfp, struct bio_set *bs);
348
349/**
350 * bio_next_split - get next @sectors from a bio, splitting if necessary
351 * @bio: bio to split
352 * @sectors: number of sectors to split from the front of @bio
353 * @gfp: gfp mask
354 * @bs: bio set to allocate from
355 *
356 * Returns a bio representing the next @sectors of @bio - if the bio is smaller
357 * than @sectors, returns the original bio unchanged.
358 */
359static inline struct bio *bio_next_split(struct bio *bio, int sectors,
360 gfp_t gfp, struct bio_set *bs)
361{
362 if (sectors >= bio_sectors(bio))
363 return bio;
364
365 return bio_split(bio, sectors, gfp, bs);
366}
367
011067b0
N		 368enum {
369 BIOSET_NEED_BVECS = BIT(0),
47e0fb46 370 BIOSET_NEED_RESCUER = BIT(1),
011067b0 371};
dad08527
KO		 372extern int bioset_init(struct bio_set *, unsigned int, unsigned int, int flags);
373extern void bioset_exit(struct bio_set *);
8aa6ba2f 374extern int biovec_init_pool(mempool_t *pool, int pool_entries);
28e89fd9 375extern int bioset_init_from_src(struct bio_set *bs, struct bio_set *src);
1da177e4 376
7a88fa19 377extern struct bio *bio_alloc_bioset(gfp_t, unsigned int, struct bio_set *);
1da177e4
LT		 378extern void bio_put(struct bio *);
379
59d276fe
KO		 380extern void __bio_clone_fast(struct bio *, struct bio *);
381extern struct bio *bio_clone_fast(struct bio *, gfp_t, struct bio_set *);
bf800ef1 382
f4f8154a 383extern struct bio_set fs_bio_set;
3f86a82a
KO		 384
385static inline struct bio *bio_alloc(gfp_t gfp_mask, unsigned int nr_iovecs)
386{
f4f8154a 387 return bio_alloc_bioset(gfp_mask, nr_iovecs, &fs_bio_set);
3f86a82a
KO		 388}
389
390static inline struct bio *bio_kmalloc(gfp_t gfp_mask, unsigned int nr_iovecs)
391{
392 return bio_alloc_bioset(gfp_mask, nr_iovecs, NULL);
393}
394
1e3914d4
CH		 395extern blk_qc_t submit_bio(struct bio *);
396
4246a0b6
CH		 397extern void bio_endio(struct bio *);
398
399static inline void bio_io_error(struct bio *bio)
400{
4e4cbee9 401 bio->bi_status = BLK_STS_IOERR;
4246a0b6
CH		 402 bio_endio(bio);
403}
404
03a07c92
GR		 405static inline void bio_wouldblock_error(struct bio *bio)
406{
407 bio->bi_status = BLK_STS_AGAIN;
4246a0b6
CH		 408 bio_endio(bio);
409}
410
1da177e4
LT		 411struct request_queue;
412extern int bio_phys_segments(struct request_queue *, struct bio *);
1da177e4 413
4e49ea4a 414extern int submit_bio_wait(struct bio *bio);
054bdf64
KO		 415extern void bio_advance(struct bio *, unsigned);
416
3a83f467
ML		 417extern void bio_init(struct bio *bio, struct bio_vec *table,
418 unsigned short max_vecs);
9ae3b3f5 419extern void bio_uninit(struct bio *);
f44b48c7 420extern void bio_reset(struct bio *);
196d38bc 421void bio_chain(struct bio *, struct bio *);
1da177e4
LT		 422
423extern int bio_add_page(struct bio *, struct page *, unsigned int,unsigned int);
6e68af66
MC		 424extern int bio_add_pc_page(struct request_queue *, struct bio *, struct page *,
425 unsigned int, unsigned int);
0aa69fd3
CH		 426bool __bio_try_merge_page(struct bio *bio, struct page *page,
427 unsigned int len, unsigned int off);
428void __bio_add_page(struct bio *bio, struct page *page,
429 unsigned int len, unsigned int off);
2cefe4db 430int bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter);
152e283f 431struct rq_map_data;
f1970baf 432extern struct bio *bio_map_user_iov(struct request_queue *,
e81cef5d 433 struct iov_iter *, gfp_t);
1da177e4 434extern void bio_unmap_user(struct bio *);
df46b9a4 435extern struct bio *bio_map_kern(struct request_queue *, void *, unsigned int,
27496a8c 436 gfp_t);
68154e90
FT		 437extern struct bio *bio_copy_kern(struct request_queue *, void *, unsigned int,
438 gfp_t, int);
1da177e4
LT		 439extern void bio_set_pages_dirty(struct bio *bio);
440extern void bio_check_pages_dirty(struct bio *bio);
2d4dc890 441
ddcf35d3 442void generic_start_io_acct(struct request_queue *q, int op,
d62e26b3 443 unsigned long sectors, struct hd_struct *part);
ddcf35d3 444void generic_end_io_acct(struct request_queue *q, int op,
d62e26b3
JA		 445 struct hd_struct *part,
446 unsigned long start_time);
394ffa50 447
2d4dc890
IL		 448#ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
449# error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform"
450#endif
451#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
452extern void bio_flush_dcache_pages(struct bio *bi);
453#else
454static inline void bio_flush_dcache_pages(struct bio *bi)
455{
456}
457#endif
458
45db54d5
KO		 459extern void bio_copy_data_iter(struct bio *dst, struct bvec_iter *dst_iter,
460 struct bio *src, struct bvec_iter *src_iter);
16ac3d63 461extern void bio_copy_data(struct bio *dst, struct bio *src);
45db54d5 462extern void bio_list_copy_data(struct bio *dst, struct bio *src);
491221f8 463extern void bio_free_pages(struct bio *bio);
16ac3d63 464
152e283f 465extern struct bio *bio_copy_user_iov(struct request_queue *,
86d564c8 466 struct rq_map_data *,
e81cef5d 467 struct iov_iter *,
26e49cfc 468 gfp_t);
1da177e4 469extern int bio_uncopy_user(struct bio *);
38a72dac
KO		 470void zero_fill_bio_iter(struct bio *bio, struct bvec_iter iter);
471
472static inline void zero_fill_bio(struct bio *bio)
473{
474 zero_fill_bio_iter(bio, bio->bi_iter);
475}
476
9f060e22
KO		 477extern struct bio_vec *bvec_alloc(gfp_t, int, unsigned long *, mempool_t *);
478extern void bvec_free(mempool_t *, struct bio_vec *, unsigned int);
7ba1ba12 479extern unsigned int bvec_nr_vecs(unsigned short idx);
9c0fb1e3 480extern const char *bio_devname(struct bio *bio, char *buffer);
51d654e1 481
74d46992
CH		 482#define bio_set_dev(bio, bdev) \
483do { \
111be883
SL		 484 if ((bio)->bi_disk != (bdev)->bd_disk) \
485 bio_clear_flag(bio, BIO_THROTTLED);\
74d46992
CH		 486 (bio)->bi_disk = (bdev)->bd_disk; \
487 (bio)->bi_partno = (bdev)->bd_partno; \
5cdf2e3f 488 bio_associate_blkg(bio); \
74d46992
CH		 489} while (0)
490
491#define bio_copy_dev(dst, src) \
492do { \
493 (dst)->bi_disk = (src)->bi_disk; \
494 (dst)->bi_partno = (src)->bi_partno; \
db6638d7 495 bio_clone_blkg_association(dst, src); \
74d46992
CH		 496} while (0)
497
498#define bio_dev(bio) \
499 disk_devt((bio)->bi_disk)
500
0d3bd88d 501#if defined(CONFIG_MEMCG) && defined(CONFIG_BLK_CGROUP)
6a7f6d86 502void bio_associate_blkg_from_page(struct bio *bio, struct page *page);
0d3bd88d 503#else
6a7f6d86
DZ		 504static inline void bio_associate_blkg_from_page(struct bio *bio,
505 struct page *page) { }
0d3bd88d
TH		 506#endif
507
852c788f 508#ifdef CONFIG_BLK_CGROUP
2268c0fe
DZ		 509void bio_disassociate_blkg(struct bio *bio);
510void bio_associate_blkg(struct bio *bio);
fd42df30
DZ		 511void bio_associate_blkg_from_css(struct bio *bio,
512 struct cgroup_subsys_state *css);
db6638d7 513void bio_clone_blkg_association(struct bio *dst, struct bio *src);
852c788f 514#else /* CONFIG_BLK_CGROUP */
2268c0fe
DZ		 515static inline void bio_disassociate_blkg(struct bio *bio) { }
516static inline void bio_associate_blkg(struct bio *bio) { }
fd42df30
DZ		 517static inline void bio_associate_blkg_from_css(struct bio *bio,
518 struct cgroup_subsys_state *css)
519{ }
db6638d7
DZ		 520static inline void bio_clone_blkg_association(struct bio *dst,
521 struct bio *src) { }
852c788f
TH		 522#endif /* CONFIG_BLK_CGROUP */
523
1da177e4
LT		 524#ifdef CONFIG_HIGHMEM
525/*
20b636bf
AB		 526 * remember never ever reenable interrupts between a bvec_kmap_irq and
527 * bvec_kunmap_irq!
1da177e4 528 */
4f570f99 529static inline char *bvec_kmap_irq(struct bio_vec *bvec, unsigned long *flags)
1da177e4
LT		 530{
531 unsigned long addr;
532
533 /*
534 * might not be a highmem page, but the preempt/irq count
535 * balancing is a lot nicer this way
536 */
537 local_irq_save(*flags);
e8e3c3d6 538 addr = (unsigned long) kmap_atomic(bvec->bv_page);
1da177e4
LT		 539
540 BUG_ON(addr & ~PAGE_MASK);
541
542 return (char *) addr + bvec->bv_offset;
543}
544
4f570f99 545static inline void bvec_kunmap_irq(char *buffer, unsigned long *flags)
1da177e4
LT		 546{
547 unsigned long ptr = (unsigned long) buffer & PAGE_MASK;
548
e8e3c3d6 549 kunmap_atomic((void *) ptr);
1da177e4
LT		 550 local_irq_restore(*flags);
551}
552
553#else
11a691be
GU		 554static inline char *bvec_kmap_irq(struct bio_vec *bvec, unsigned long *flags)
555{
556 return page_address(bvec->bv_page) + bvec->bv_offset;
557}
558
559static inline void bvec_kunmap_irq(char *buffer, unsigned long *flags)
560{
561 *flags = 0;
562}
1da177e4
LT		 563#endif
564
8f3d8ba2 565/*
e686307f 566 * BIO list management for use by remapping drivers (e.g. DM or MD) and loop.
8f3d8ba2
CH		 567 *
568 * A bio_list anchors a singly-linked list of bios chained through the bi_next
569 * member of the bio. The bio_list also caches the last list member to allow
570 * fast access to the tail.
571 */
572struct bio_list {
573 struct bio *head;
574 struct bio *tail;
575};
576
577static inline int bio_list_empty(const struct bio_list *bl)
578{
579 return bl->head == NULL;
580}
581
582static inline void bio_list_init(struct bio_list *bl)
583{
584 bl->head = bl->tail = NULL;
585}
586
320ae51f
JA		 587#define BIO_EMPTY_LIST { NULL, NULL }
588
8f3d8ba2
CH		 589#define bio_list_for_each(bio, bl) \
590 for (bio = (bl)->head; bio; bio = bio->bi_next)
591
592static inline unsigned bio_list_size(const struct bio_list *bl)
593{
594 unsigned sz = 0;
595 struct bio *bio;
596
597 bio_list_for_each(bio, bl)
598 sz++;
599
600 return sz;
601}
602
603static inline void bio_list_add(struct bio_list *bl, struct bio *bio)
604{
605 bio->bi_next = NULL;
606
607 if (bl->tail)
608 bl->tail->bi_next = bio;
609 else
610 bl->head = bio;
611
612 bl->tail = bio;
613}
614
615static inline void bio_list_add_head(struct bio_list *bl, struct bio *bio)
616{
617 bio->bi_next = bl->head;
618
619 bl->head = bio;
620
621 if (!bl->tail)
622 bl->tail = bio;
623}
624
625static inline void bio_list_merge(struct bio_list *bl, struct bio_list *bl2)
626{
627 if (!bl2->head)
628 return;
629
630 if (bl->tail)
631 bl->tail->bi_next = bl2->head;
632 else
633 bl->head = bl2->head;
634
635 bl->tail = bl2->tail;
636}
637
638static inline void bio_list_merge_head(struct bio_list *bl,
639 struct bio_list *bl2)
640{
641 if (!bl2->head)
642 return;
643
644 if (bl->head)
645 bl2->tail->bi_next = bl->head;
646 else
647 bl->tail = bl2->tail;
648
649 bl->head = bl2->head;
650}
651
13685a16
GU		 652static inline struct bio *bio_list_peek(struct bio_list *bl)
653{
654 return bl->head;
655}
656
8f3d8ba2
CH		 657static inline struct bio *bio_list_pop(struct bio_list *bl)
658{
659 struct bio *bio = bl->head;
660
661 if (bio) {
662 bl->head = bl->head->bi_next;
663 if (!bl->head)
664 bl->tail = NULL;
665
666 bio->bi_next = NULL;
667 }
668
669 return bio;
670}
671
672static inline struct bio *bio_list_get(struct bio_list *bl)
673{
674 struct bio *bio = bl->head;
675
676 bl->head = bl->tail = NULL;
677
678 return bio;
679}
680
0ef5a50c
MS		 681/*
682 * Increment chain count for the bio. Make sure the CHAIN flag update
683 * is visible before the raised count.
684 */
685static inline void bio_inc_remaining(struct bio *bio)
686{
687 bio_set_flag(bio, BIO_CHAIN);
688 smp_mb__before_atomic();
689 atomic_inc(&bio->__bi_remaining);
690}
691
57fb233f
KO		 692/*
693 * bio_set is used to allow other portions of the IO system to
694 * allocate their own private memory pools for bio and iovec structures.
695 * These memory pools in turn all allocate from the bio_slab
696 * and the bvec_slabs[].
697 */
698#define BIO_POOL_SIZE 2
57fb233f
KO		 699
700struct bio_set {
701 struct kmem_cache *bio_slab;
702 unsigned int front_pad;
703
8aa6ba2f
KO		 704 mempool_t bio_pool;
705 mempool_t bvec_pool;
57fb233f 706#if defined(CONFIG_BLK_DEV_INTEGRITY)
8aa6ba2f
KO		 707 mempool_t bio_integrity_pool;
708 mempool_t bvec_integrity_pool;
57fb233f 709#endif
df2cb6da
KO		 710
711 /*
712 * Deadlock avoidance for stacking block drivers: see comments in
713 * bio_alloc_bioset() for details
714 */
715 spinlock_t rescue_lock;
716 struct bio_list rescue_list;
717 struct work_struct rescue_work;
718 struct workqueue_struct *rescue_workqueue;
57fb233f
KO		 719};
720
721struct biovec_slab {
722 int nr_vecs;
723 char *name;
724 struct kmem_cache *slab;
725};
726
338aa96d
KO		 727static inline bool bioset_initialized(struct bio_set *bs)
728{
729 return bs->bio_slab != NULL;
730}
731
57fb233f
KO		 732/*
733 * a small number of entries is fine, not going to be performance critical.
734 * basically we just need to survive
735 */
736#define BIO_SPLIT_ENTRIES 2
737
7ba1ba12
MP		 738#if defined(CONFIG_BLK_DEV_INTEGRITY)
739
d57a5f7c
KO		 740#define bip_for_each_vec(bvl, bip, iter) \
741 for_each_bvec(bvl, (bip)->bip_vec, iter, (bip)->bip_iter)
7ba1ba12 742
13f05c8d
MP		 743#define bio_for_each_integrity_vec(_bvl, _bio, _iter) \
744 for_each_bio(_bio) \
745 bip_for_each_vec(_bvl, _bio->bi_integrity, _iter)
746
7ba1ba12 747extern struct bio_integrity_payload *bio_integrity_alloc(struct bio *, gfp_t, unsigned int);
7ba1ba12 748extern int bio_integrity_add_page(struct bio *, struct page *, unsigned int, unsigned int);
e23947bd 749extern bool bio_integrity_prep(struct bio *);
7ba1ba12 750extern void bio_integrity_advance(struct bio *, unsigned int);
fbd08e76 751extern void bio_integrity_trim(struct bio *);
1e2a410f 752extern int bio_integrity_clone(struct bio *, struct bio *, gfp_t);
7878cba9
MP		 753extern int bioset_integrity_create(struct bio_set *, int);
754extern void bioset_integrity_free(struct bio_set *);
755extern void bio_integrity_init(void);
7ba1ba12
MP		 756
757#else /* CONFIG_BLK_DEV_INTEGRITY */
758
c611529e 759static inline void *bio_integrity(struct bio *bio)
6898e3bd 760{
c611529e 761 return NULL;
6898e3bd
MP		 762}
763
6898e3bd
MP		 764static inline int bioset_integrity_create(struct bio_set *bs, int pool_size)
765{
766 return 0;
767}
768
769static inline void bioset_integrity_free (struct bio_set *bs)
770{
771 return;
772}
773
e23947bd 774static inline bool bio_integrity_prep(struct bio *bio)
6898e3bd 775{
e23947bd 776 return true;
6898e3bd
MP		 777}
778
0c614e2d 779static inline int bio_integrity_clone(struct bio *bio, struct bio *bio_src,
1e2a410f 780 gfp_t gfp_mask)
0c614e2d
SR		 781{
782 return 0;
783}
6898e3bd 784
6898e3bd
MP		 785static inline void bio_integrity_advance(struct bio *bio,
786 unsigned int bytes_done)
787{
788 return;
789}
790
fbd08e76 791static inline void bio_integrity_trim(struct bio *bio)
6898e3bd
MP		 792{
793 return;
794}
795
796static inline void bio_integrity_init(void)
797{
798 return;
799}
7ba1ba12 800
c611529e
MP		 801static inline bool bio_integrity_flagged(struct bio *bio, enum bip_flags flag)
802{
803 return false;
804}
805
06c1e390
KB		 806static inline void *bio_integrity_alloc(struct bio * bio, gfp_t gfp,
807 unsigned int nr)
808{
809 return ERR_PTR(-EINVAL);
810}
811
812static inline int bio_integrity_add_page(struct bio *bio, struct page *page,
813 unsigned int len, unsigned int offset)
814{
815 return 0;
816}
817
7ba1ba12
MP		 818#endif /* CONFIG_BLK_DEV_INTEGRITY */
819
02a5e0ac 820#endif /* CONFIG_BLOCK */
1da177e4 821#endif /* __LINUX_BIO_H */
Linux 6.x block layer and io_uring tree(s)