Merge tag '5.0-rc1-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6
[linux-2.6-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 unsigned bio_pages_all(struct bio *bio)
267{
268 WARN_ON_ONCE(bio_flagged(bio, BIO_CLONED));
269 return bio->bi_vcnt;
270}
271
272static inline struct bio_vec *bio_first_bvec_all(struct bio *bio)
273{
274 WARN_ON_ONCE(bio_flagged(bio, BIO_CLONED));
275 return bio->bi_io_vec;
276}
277
278static inline struct page *bio_first_page_all(struct bio *bio)
279{
280 return bio_first_bvec_all(bio)->bv_page;
281}
282
283static inline struct bio_vec *bio_last_bvec_all(struct bio *bio)
284{
285 WARN_ON_ONCE(bio_flagged(bio, BIO_CLONED));
286 return &bio->bi_io_vec[bio->bi_vcnt - 1];
287}
288
c611529e
MP
289enum bip_flags {
290 BIP_BLOCK_INTEGRITY = 1 << 0, /* block layer owns integrity data */
291 BIP_MAPPED_INTEGRITY = 1 << 1, /* ref tag has been remapped */
292 BIP_CTRL_NOCHECK = 1 << 2, /* disable HBA integrity checking */
293 BIP_DISK_NOCHECK = 1 << 3, /* disable disk integrity checking */
294 BIP_IP_CHECKSUM = 1 << 4, /* IP checksum */
295};
296
7ba1ba12
MP
297/*
298 * bio integrity payload
299 */
300struct bio_integrity_payload {
301 struct bio *bip_bio; /* parent bio */
7ba1ba12 302
d57a5f7c 303 struct bvec_iter bip_iter;
7ba1ba12 304
7878cba9 305 unsigned short bip_slab; /* slab the bip came from */
7ba1ba12 306 unsigned short bip_vcnt; /* # of integrity bio_vecs */
cbcd1054 307 unsigned short bip_max_vcnt; /* integrity bio_vec slots */
b1f01388 308 unsigned short bip_flags; /* control flags */
7ba1ba12 309
7759eb23
ML
310 struct bvec_iter bio_iter; /* for rewinding parent bio */
311
7ba1ba12 312 struct work_struct bip_work; /* I/O completion */
6fda981c
KO
313
314 struct bio_vec *bip_vec;
315 struct bio_vec bip_inline_vecs[0];/* embedded bvec array */
7ba1ba12 316};
18593088 317
06c1e390
KB
318#if defined(CONFIG_BLK_DEV_INTEGRITY)
319
320static inline struct bio_integrity_payload *bio_integrity(struct bio *bio)
321{
1eff9d32 322 if (bio->bi_opf & REQ_INTEGRITY)
06c1e390
KB
323 return bio->bi_integrity;
324
325 return NULL;
326}
327
c611529e
MP
328static inline bool bio_integrity_flagged(struct bio *bio, enum bip_flags flag)
329{
330 struct bio_integrity_payload *bip = bio_integrity(bio);
331
332 if (bip)
333 return bip->bip_flags & flag;
334
335 return false;
336}
b1f01388 337
18593088
MP
338static inline sector_t bip_get_seed(struct bio_integrity_payload *bip)
339{
340 return bip->bip_iter.bi_sector;
341}
342
343static inline void bip_set_seed(struct bio_integrity_payload *bip,
344 sector_t seed)
345{
346 bip->bip_iter.bi_sector = seed;
347}
348
7ba1ba12 349#endif /* CONFIG_BLK_DEV_INTEGRITY */
1da177e4 350
6678d83f 351extern void bio_trim(struct bio *bio, int offset, int size);
20d0189b
KO
352extern struct bio *bio_split(struct bio *bio, int sectors,
353 gfp_t gfp, struct bio_set *bs);
354
355/**
356 * bio_next_split - get next @sectors from a bio, splitting if necessary
357 * @bio: bio to split
358 * @sectors: number of sectors to split from the front of @bio
359 * @gfp: gfp mask
360 * @bs: bio set to allocate from
361 *
362 * Returns a bio representing the next @sectors of @bio - if the bio is smaller
363 * than @sectors, returns the original bio unchanged.
364 */
365static inline struct bio *bio_next_split(struct bio *bio, int sectors,
366 gfp_t gfp, struct bio_set *bs)
367{
368 if (sectors >= bio_sectors(bio))
369 return bio;
370
371 return bio_split(bio, sectors, gfp, bs);
372}
373
011067b0
N
374enum {
375 BIOSET_NEED_BVECS = BIT(0),
47e0fb46 376 BIOSET_NEED_RESCUER = BIT(1),
011067b0 377};
dad08527
KO
378extern int bioset_init(struct bio_set *, unsigned int, unsigned int, int flags);
379extern void bioset_exit(struct bio_set *);
8aa6ba2f 380extern int biovec_init_pool(mempool_t *pool, int pool_entries);
28e89fd9 381extern int bioset_init_from_src(struct bio_set *bs, struct bio_set *src);
1da177e4 382
7a88fa19 383extern struct bio *bio_alloc_bioset(gfp_t, unsigned int, struct bio_set *);
1da177e4
LT
384extern void bio_put(struct bio *);
385
59d276fe
KO
386extern void __bio_clone_fast(struct bio *, struct bio *);
387extern struct bio *bio_clone_fast(struct bio *, gfp_t, struct bio_set *);
bf800ef1 388
f4f8154a 389extern struct bio_set fs_bio_set;
3f86a82a
KO
390
391static inline struct bio *bio_alloc(gfp_t gfp_mask, unsigned int nr_iovecs)
392{
f4f8154a 393 return bio_alloc_bioset(gfp_mask, nr_iovecs, &fs_bio_set);
3f86a82a
KO
394}
395
396static inline struct bio *bio_kmalloc(gfp_t gfp_mask, unsigned int nr_iovecs)
397{
398 return bio_alloc_bioset(gfp_mask, nr_iovecs, NULL);
399}
400
1e3914d4
CH
401extern blk_qc_t submit_bio(struct bio *);
402
4246a0b6
CH
403extern void bio_endio(struct bio *);
404
405static inline void bio_io_error(struct bio *bio)
406{
4e4cbee9 407 bio->bi_status = BLK_STS_IOERR;
4246a0b6
CH
408 bio_endio(bio);
409}
410
03a07c92
GR
411static inline void bio_wouldblock_error(struct bio *bio)
412{
413 bio->bi_status = BLK_STS_AGAIN;
4246a0b6
CH
414 bio_endio(bio);
415}
416
1da177e4
LT
417struct request_queue;
418extern int bio_phys_segments(struct request_queue *, struct bio *);
1da177e4 419
4e49ea4a 420extern int submit_bio_wait(struct bio *bio);
054bdf64
KO
421extern void bio_advance(struct bio *, unsigned);
422
3a83f467
ML
423extern void bio_init(struct bio *bio, struct bio_vec *table,
424 unsigned short max_vecs);
9ae3b3f5 425extern void bio_uninit(struct bio *);
f44b48c7 426extern void bio_reset(struct bio *);
196d38bc 427void bio_chain(struct bio *, struct bio *);
1da177e4
LT
428
429extern int bio_add_page(struct bio *, struct page *, unsigned int,unsigned int);
6e68af66
MC
430extern int bio_add_pc_page(struct request_queue *, struct bio *, struct page *,
431 unsigned int, unsigned int);
0aa69fd3
CH
432bool __bio_try_merge_page(struct bio *bio, struct page *page,
433 unsigned int len, unsigned int off);
434void __bio_add_page(struct bio *bio, struct page *page,
435 unsigned int len, unsigned int off);
2cefe4db 436int bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter);
152e283f 437struct rq_map_data;
f1970baf 438extern struct bio *bio_map_user_iov(struct request_queue *,
e81cef5d 439 struct iov_iter *, gfp_t);
1da177e4 440extern void bio_unmap_user(struct bio *);
df46b9a4 441extern struct bio *bio_map_kern(struct request_queue *, void *, unsigned int,
27496a8c 442 gfp_t);
68154e90
FT
443extern struct bio *bio_copy_kern(struct request_queue *, void *, unsigned int,
444 gfp_t, int);
1da177e4
LT
445extern void bio_set_pages_dirty(struct bio *bio);
446extern void bio_check_pages_dirty(struct bio *bio);
2d4dc890 447
ddcf35d3 448void generic_start_io_acct(struct request_queue *q, int op,
d62e26b3 449 unsigned long sectors, struct hd_struct *part);
ddcf35d3 450void generic_end_io_acct(struct request_queue *q, int op,
d62e26b3
JA
451 struct hd_struct *part,
452 unsigned long start_time);
394ffa50 453
2d4dc890
IL
454#ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
455# error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform"
456#endif
457#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
458extern void bio_flush_dcache_pages(struct bio *bi);
459#else
460static inline void bio_flush_dcache_pages(struct bio *bi)
461{
462}
463#endif
464
45db54d5
KO
465extern void bio_copy_data_iter(struct bio *dst, struct bvec_iter *dst_iter,
466 struct bio *src, struct bvec_iter *src_iter);
16ac3d63 467extern void bio_copy_data(struct bio *dst, struct bio *src);
45db54d5 468extern void bio_list_copy_data(struct bio *dst, struct bio *src);
491221f8 469extern void bio_free_pages(struct bio *bio);
16ac3d63 470
152e283f 471extern struct bio *bio_copy_user_iov(struct request_queue *,
86d564c8 472 struct rq_map_data *,
e81cef5d 473 struct iov_iter *,
26e49cfc 474 gfp_t);
1da177e4 475extern int bio_uncopy_user(struct bio *);
38a72dac
KO
476void zero_fill_bio_iter(struct bio *bio, struct bvec_iter iter);
477
478static inline void zero_fill_bio(struct bio *bio)
479{
480 zero_fill_bio_iter(bio, bio->bi_iter);
481}
482
9f060e22
KO
483extern struct bio_vec *bvec_alloc(gfp_t, int, unsigned long *, mempool_t *);
484extern void bvec_free(mempool_t *, struct bio_vec *, unsigned int);
7ba1ba12 485extern unsigned int bvec_nr_vecs(unsigned short idx);
9c0fb1e3 486extern const char *bio_devname(struct bio *bio, char *buffer);
51d654e1 487
74d46992
CH
488#define bio_set_dev(bio, bdev) \
489do { \
111be883
SL
490 if ((bio)->bi_disk != (bdev)->bd_disk) \
491 bio_clear_flag(bio, BIO_THROTTLED);\
74d46992
CH
492 (bio)->bi_disk = (bdev)->bd_disk; \
493 (bio)->bi_partno = (bdev)->bd_partno; \
5cdf2e3f 494 bio_associate_blkg(bio); \
74d46992
CH
495} while (0)
496
497#define bio_copy_dev(dst, src) \
498do { \
499 (dst)->bi_disk = (src)->bi_disk; \
500 (dst)->bi_partno = (src)->bi_partno; \
db6638d7 501 bio_clone_blkg_association(dst, src); \
74d46992
CH
502} while (0)
503
504#define bio_dev(bio) \
505 disk_devt((bio)->bi_disk)
506
0d3bd88d 507#if defined(CONFIG_MEMCG) && defined(CONFIG_BLK_CGROUP)
6a7f6d86 508void bio_associate_blkg_from_page(struct bio *bio, struct page *page);
0d3bd88d 509#else
6a7f6d86
DZ
510static inline void bio_associate_blkg_from_page(struct bio *bio,
511 struct page *page) { }
0d3bd88d
TH
512#endif
513
852c788f 514#ifdef CONFIG_BLK_CGROUP
2268c0fe
DZ
515void bio_disassociate_blkg(struct bio *bio);
516void bio_associate_blkg(struct bio *bio);
fd42df30
DZ
517void bio_associate_blkg_from_css(struct bio *bio,
518 struct cgroup_subsys_state *css);
db6638d7 519void bio_clone_blkg_association(struct bio *dst, struct bio *src);
852c788f 520#else /* CONFIG_BLK_CGROUP */
2268c0fe
DZ
521static inline void bio_disassociate_blkg(struct bio *bio) { }
522static inline void bio_associate_blkg(struct bio *bio) { }
fd42df30
DZ
523static inline void bio_associate_blkg_from_css(struct bio *bio,
524 struct cgroup_subsys_state *css)
525{ }
db6638d7
DZ
526static inline void bio_clone_blkg_association(struct bio *dst,
527 struct bio *src) { }
852c788f
TH
528#endif /* CONFIG_BLK_CGROUP */
529
1da177e4
LT
530#ifdef CONFIG_HIGHMEM
531/*
20b636bf
AB
532 * remember never ever reenable interrupts between a bvec_kmap_irq and
533 * bvec_kunmap_irq!
1da177e4 534 */
4f570f99 535static inline char *bvec_kmap_irq(struct bio_vec *bvec, unsigned long *flags)
1da177e4
LT
536{
537 unsigned long addr;
538
539 /*
540 * might not be a highmem page, but the preempt/irq count
541 * balancing is a lot nicer this way
542 */
543 local_irq_save(*flags);
e8e3c3d6 544 addr = (unsigned long) kmap_atomic(bvec->bv_page);
1da177e4
LT
545
546 BUG_ON(addr & ~PAGE_MASK);
547
548 return (char *) addr + bvec->bv_offset;
549}
550
4f570f99 551static inline void bvec_kunmap_irq(char *buffer, unsigned long *flags)
1da177e4
LT
552{
553 unsigned long ptr = (unsigned long) buffer & PAGE_MASK;
554
e8e3c3d6 555 kunmap_atomic((void *) ptr);
1da177e4
LT
556 local_irq_restore(*flags);
557}
558
559#else
11a691be
GU
560static inline char *bvec_kmap_irq(struct bio_vec *bvec, unsigned long *flags)
561{
562 return page_address(bvec->bv_page) + bvec->bv_offset;
563}
564
565static inline void bvec_kunmap_irq(char *buffer, unsigned long *flags)
566{
567 *flags = 0;
568}
1da177e4
LT
569#endif
570
8f3d8ba2 571/*
e686307f 572 * BIO list management for use by remapping drivers (e.g. DM or MD) and loop.
8f3d8ba2
CH
573 *
574 * A bio_list anchors a singly-linked list of bios chained through the bi_next
575 * member of the bio. The bio_list also caches the last list member to allow
576 * fast access to the tail.
577 */
578struct bio_list {
579 struct bio *head;
580 struct bio *tail;
581};
582
583static inline int bio_list_empty(const struct bio_list *bl)
584{
585 return bl->head == NULL;
586}
587
588static inline void bio_list_init(struct bio_list *bl)
589{
590 bl->head = bl->tail = NULL;
591}
592
320ae51f
JA
593#define BIO_EMPTY_LIST { NULL, NULL }
594
8f3d8ba2
CH
595#define bio_list_for_each(bio, bl) \
596 for (bio = (bl)->head; bio; bio = bio->bi_next)
597
598static inline unsigned bio_list_size(const struct bio_list *bl)
599{
600 unsigned sz = 0;
601 struct bio *bio;
602
603 bio_list_for_each(bio, bl)
604 sz++;
605
606 return sz;
607}
608
609static inline void bio_list_add(struct bio_list *bl, struct bio *bio)
610{
611 bio->bi_next = NULL;
612
613 if (bl->tail)
614 bl->tail->bi_next = bio;
615 else
616 bl->head = bio;
617
618 bl->tail = bio;
619}
620
621static inline void bio_list_add_head(struct bio_list *bl, struct bio *bio)
622{
623 bio->bi_next = bl->head;
624
625 bl->head = bio;
626
627 if (!bl->tail)
628 bl->tail = bio;
629}
630
631static inline void bio_list_merge(struct bio_list *bl, struct bio_list *bl2)
632{
633 if (!bl2->head)
634 return;
635
636 if (bl->tail)
637 bl->tail->bi_next = bl2->head;
638 else
639 bl->head = bl2->head;
640
641 bl->tail = bl2->tail;
642}
643
644static inline void bio_list_merge_head(struct bio_list *bl,
645 struct bio_list *bl2)
646{
647 if (!bl2->head)
648 return;
649
650 if (bl->head)
651 bl2->tail->bi_next = bl->head;
652 else
653 bl->tail = bl2->tail;
654
655 bl->head = bl2->head;
656}
657
13685a16
GU
658static inline struct bio *bio_list_peek(struct bio_list *bl)
659{
660 return bl->head;
661}
662
8f3d8ba2
CH
663static inline struct bio *bio_list_pop(struct bio_list *bl)
664{
665 struct bio *bio = bl->head;
666
667 if (bio) {
668 bl->head = bl->head->bi_next;
669 if (!bl->head)
670 bl->tail = NULL;
671
672 bio->bi_next = NULL;
673 }
674
675 return bio;
676}
677
678static inline struct bio *bio_list_get(struct bio_list *bl)
679{
680 struct bio *bio = bl->head;
681
682 bl->head = bl->tail = NULL;
683
684 return bio;
685}
686
0ef5a50c
MS
687/*
688 * Increment chain count for the bio. Make sure the CHAIN flag update
689 * is visible before the raised count.
690 */
691static inline void bio_inc_remaining(struct bio *bio)
692{
693 bio_set_flag(bio, BIO_CHAIN);
694 smp_mb__before_atomic();
695 atomic_inc(&bio->__bi_remaining);
696}
697
57fb233f
KO
698/*
699 * bio_set is used to allow other portions of the IO system to
700 * allocate their own private memory pools for bio and iovec structures.
701 * These memory pools in turn all allocate from the bio_slab
702 * and the bvec_slabs[].
703 */
704#define BIO_POOL_SIZE 2
57fb233f
KO
705
706struct bio_set {
707 struct kmem_cache *bio_slab;
708 unsigned int front_pad;
709
8aa6ba2f
KO
710 mempool_t bio_pool;
711 mempool_t bvec_pool;
57fb233f 712#if defined(CONFIG_BLK_DEV_INTEGRITY)
8aa6ba2f
KO
713 mempool_t bio_integrity_pool;
714 mempool_t bvec_integrity_pool;
57fb233f 715#endif
df2cb6da
KO
716
717 /*
718 * Deadlock avoidance for stacking block drivers: see comments in
719 * bio_alloc_bioset() for details
720 */
721 spinlock_t rescue_lock;
722 struct bio_list rescue_list;
723 struct work_struct rescue_work;
724 struct workqueue_struct *rescue_workqueue;
57fb233f
KO
725};
726
727struct biovec_slab {
728 int nr_vecs;
729 char *name;
730 struct kmem_cache *slab;
731};
732
338aa96d
KO
733static inline bool bioset_initialized(struct bio_set *bs)
734{
735 return bs->bio_slab != NULL;
736}
737
57fb233f
KO
738/*
739 * a small number of entries is fine, not going to be performance critical.
740 * basically we just need to survive
741 */
742#define BIO_SPLIT_ENTRIES 2
743
7ba1ba12
MP
744#if defined(CONFIG_BLK_DEV_INTEGRITY)
745
d57a5f7c
KO
746#define bip_for_each_vec(bvl, bip, iter) \
747 for_each_bvec(bvl, (bip)->bip_vec, iter, (bip)->bip_iter)
7ba1ba12 748
13f05c8d
MP
749#define bio_for_each_integrity_vec(_bvl, _bio, _iter) \
750 for_each_bio(_bio) \
751 bip_for_each_vec(_bvl, _bio->bi_integrity, _iter)
752
7ba1ba12 753extern struct bio_integrity_payload *bio_integrity_alloc(struct bio *, gfp_t, unsigned int);
7ba1ba12 754extern int bio_integrity_add_page(struct bio *, struct page *, unsigned int, unsigned int);
e23947bd 755extern bool bio_integrity_prep(struct bio *);
7ba1ba12 756extern void bio_integrity_advance(struct bio *, unsigned int);
fbd08e76 757extern void bio_integrity_trim(struct bio *);
1e2a410f 758extern int bio_integrity_clone(struct bio *, struct bio *, gfp_t);
7878cba9
MP
759extern int bioset_integrity_create(struct bio_set *, int);
760extern void bioset_integrity_free(struct bio_set *);
761extern void bio_integrity_init(void);
7ba1ba12
MP
762
763#else /* CONFIG_BLK_DEV_INTEGRITY */
764
c611529e 765static inline void *bio_integrity(struct bio *bio)
6898e3bd 766{
c611529e 767 return NULL;
6898e3bd
MP
768}
769
6898e3bd
MP
770static inline int bioset_integrity_create(struct bio_set *bs, int pool_size)
771{
772 return 0;
773}
774
775static inline void bioset_integrity_free (struct bio_set *bs)
776{
777 return;
778}
779
e23947bd 780static inline bool bio_integrity_prep(struct bio *bio)
6898e3bd 781{
e23947bd 782 return true;
6898e3bd
MP
783}
784
0c614e2d 785static inline int bio_integrity_clone(struct bio *bio, struct bio *bio_src,
1e2a410f 786 gfp_t gfp_mask)
0c614e2d
SR
787{
788 return 0;
789}
6898e3bd 790
6898e3bd
MP
791static inline void bio_integrity_advance(struct bio *bio,
792 unsigned int bytes_done)
793{
794 return;
795}
796
fbd08e76 797static inline void bio_integrity_trim(struct bio *bio)
6898e3bd
MP
798{
799 return;
800}
801
802static inline void bio_integrity_init(void)
803{
804 return;
805}
7ba1ba12 806
c611529e
MP
807static inline bool bio_integrity_flagged(struct bio *bio, enum bip_flags flag)
808{
809 return false;
810}
811
06c1e390
KB
812static inline void *bio_integrity_alloc(struct bio * bio, gfp_t gfp,
813 unsigned int nr)
814{
815 return ERR_PTR(-EINVAL);
816}
817
818static inline int bio_integrity_add_page(struct bio *bio, struct page *page,
819 unsigned int len, unsigned int offset)
820{
821 return 0;
822}
823
7ba1ba12
MP
824#endif /* CONFIG_BLK_DEV_INTEGRITY */
825
02a5e0ac 826#endif /* CONFIG_BLOCK */
1da177e4 827#endif /* __LINUX_BIO_H */