fs: Introduce IOMAP_NOWAIT
[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>
187f1882 24#include <linux/bug.h>
1da177e4 25
02a5e0ac
DH
26#ifdef CONFIG_BLOCK
27
1da177e4
LT
28#include <asm/io.h>
29
7cc01581
TH
30/* struct bio, bio_vec and BIO_* flags are defined in blk_types.h */
31#include <linux/blk_types.h>
32
1da177e4
LT
33#define BIO_DEBUG
34
35#ifdef BIO_DEBUG
36#define BIO_BUG_ON BUG_ON
37#else
38#define BIO_BUG_ON
39#endif
40
d84a8477 41#define BIO_MAX_PAGES 256
1da177e4 42
43b62ce3
MC
43#define bio_prio(bio) (bio)->bi_ioprio
44#define bio_set_prio(bio, prio) ((bio)->bi_ioprio = prio)
22e2c507 45
4550dd6c
KO
46#define bio_iter_iovec(bio, iter) \
47 bvec_iter_bvec((bio)->bi_io_vec, (iter))
48
49#define bio_iter_page(bio, iter) \
50 bvec_iter_page((bio)->bi_io_vec, (iter))
51#define bio_iter_len(bio, iter) \
52 bvec_iter_len((bio)->bi_io_vec, (iter))
53#define bio_iter_offset(bio, iter) \
54 bvec_iter_offset((bio)->bi_io_vec, (iter))
55
56#define bio_page(bio) bio_iter_page((bio), (bio)->bi_iter)
57#define bio_offset(bio) bio_iter_offset((bio), (bio)->bi_iter)
58#define bio_iovec(bio) bio_iter_iovec((bio), (bio)->bi_iter)
7988613b 59
458b76ed
KO
60#define bio_multiple_segments(bio) \
61 ((bio)->bi_iter.bi_size != bio_iovec(bio).bv_len)
4f024f37
KO
62#define bio_sectors(bio) ((bio)->bi_iter.bi_size >> 9)
63#define bio_end_sector(bio) ((bio)->bi_iter.bi_sector + bio_sectors((bio)))
bf2de6f5 64
d3849953
CH
65/*
66 * Return the data direction, READ or WRITE.
67 */
68#define bio_data_dir(bio) \
69 (op_is_write(bio_op(bio)) ? WRITE : READ)
70
458b76ed
KO
71/*
72 * Check whether this bio carries any data or not. A NULL bio is allowed.
73 */
74static inline bool bio_has_data(struct bio *bio)
75{
76 if (bio &&
77 bio->bi_iter.bi_size &&
7afafc8a 78 bio_op(bio) != REQ_OP_DISCARD &&
a6f0788e
CK
79 bio_op(bio) != REQ_OP_SECURE_ERASE &&
80 bio_op(bio) != REQ_OP_WRITE_ZEROES)
458b76ed
KO
81 return true;
82
83 return false;
84}
85
95fe6c1a
MC
86static inline bool bio_no_advance_iter(struct bio *bio)
87{
7afafc8a
AH
88 return bio_op(bio) == REQ_OP_DISCARD ||
89 bio_op(bio) == REQ_OP_SECURE_ERASE ||
a6f0788e
CK
90 bio_op(bio) == REQ_OP_WRITE_SAME ||
91 bio_op(bio) == REQ_OP_WRITE_ZEROES;
95fe6c1a
MC
92}
93
458b76ed
KO
94static inline bool bio_mergeable(struct bio *bio)
95{
1eff9d32 96 if (bio->bi_opf & REQ_NOMERGE_FLAGS)
458b76ed
KO
97 return false;
98
99 return true;
100}
101
2e46e8b2 102static inline unsigned int bio_cur_bytes(struct bio *bio)
bf2de6f5 103{
458b76ed 104 if (bio_has_data(bio))
a4ad39b1 105 return bio_iovec(bio).bv_len;
fb2dce86 106 else /* dataless requests such as discard */
4f024f37 107 return bio->bi_iter.bi_size;
bf2de6f5
JA
108}
109
110static inline void *bio_data(struct bio *bio)
111{
458b76ed 112 if (bio_has_data(bio))
bf2de6f5
JA
113 return page_address(bio_page(bio)) + bio_offset(bio);
114
115 return NULL;
116}
1da177e4
LT
117
118/*
119 * will die
120 */
121#define bio_to_phys(bio) (page_to_phys(bio_page((bio))) + (unsigned long) bio_offset((bio)))
122#define bvec_to_phys(bv) (page_to_phys((bv)->bv_page) + (unsigned long) (bv)->bv_offset)
123
124/*
125 * queues that have highmem support enabled may still need to revert to
126 * PIO transfers occasionally and thus map high pages temporarily. For
127 * permanent PIO fall back, user is probably better off disabling highmem
128 * I/O completely on that queue (see ide-dma for example)
129 */
f619d254
KO
130#define __bio_kmap_atomic(bio, iter) \
131 (kmap_atomic(bio_iter_iovec((bio), (iter)).bv_page) + \
132 bio_iter_iovec((bio), (iter)).bv_offset)
1da177e4 133
f619d254 134#define __bio_kunmap_atomic(addr) kunmap_atomic(addr)
1da177e4
LT
135
136/*
137 * merge helpers etc
138 */
139
f92131c3
JF
140/* Default implementation of BIOVEC_PHYS_MERGEABLE */
141#define __BIOVEC_PHYS_MERGEABLE(vec1, vec2) \
142 ((bvec_to_phys((vec1)) + (vec1)->bv_len) == bvec_to_phys((vec2)))
143
1da177e4
LT
144/*
145 * allow arch override, for eg virtualized architectures (put in asm/io.h)
146 */
147#ifndef BIOVEC_PHYS_MERGEABLE
148#define BIOVEC_PHYS_MERGEABLE(vec1, vec2) \
f92131c3 149 __BIOVEC_PHYS_MERGEABLE(vec1, vec2)
1da177e4
LT
150#endif
151
1da177e4
LT
152#define __BIO_SEG_BOUNDARY(addr1, addr2, mask) \
153 (((addr1) | (mask)) == (((addr2) - 1) | (mask)))
154#define BIOVEC_SEG_BOUNDARY(q, b1, b2) \
ae03bf63 155 __BIO_SEG_BOUNDARY(bvec_to_phys((b1)), bvec_to_phys((b2)) + (b2)->bv_len, queue_segment_boundary((q)))
1da177e4 156
d74c6d51
KO
157/*
158 * drivers should _never_ use the all version - the bio may have been split
159 * before it got to the driver and the driver won't own all of it
160 */
161#define bio_for_each_segment_all(bvl, bio, i) \
f619d254 162 for (i = 0, bvl = (bio)->bi_io_vec; i < (bio)->bi_vcnt; i++, bvl++)
d74c6d51 163
4550dd6c
KO
164static inline void bio_advance_iter(struct bio *bio, struct bvec_iter *iter,
165 unsigned bytes)
166{
167 iter->bi_sector += bytes >> 9;
168
95fe6c1a 169 if (bio_no_advance_iter(bio))
4550dd6c
KO
170 iter->bi_size -= bytes;
171 else
172 bvec_iter_advance(bio->bi_io_vec, iter, bytes);
173}
174
7988613b
KO
175#define __bio_for_each_segment(bvl, bio, iter, start) \
176 for (iter = (start); \
4550dd6c
KO
177 (iter).bi_size && \
178 ((bvl = bio_iter_iovec((bio), (iter))), 1); \
179 bio_advance_iter((bio), &(iter), (bvl).bv_len))
7988613b
KO
180
181#define bio_for_each_segment(bvl, bio, iter) \
182 __bio_for_each_segment(bvl, bio, iter, (bio)->bi_iter)
183
4550dd6c 184#define bio_iter_last(bvec, iter) ((iter).bi_size == (bvec).bv_len)
1da177e4 185
f4595875 186static inline unsigned bio_segments(struct bio *bio)
458b76ed
KO
187{
188 unsigned segs = 0;
189 struct bio_vec bv;
190 struct bvec_iter iter;
191
8423ae3d 192 /*
a6f0788e
CK
193 * We special case discard/write same/write zeroes, because they
194 * interpret bi_size differently:
8423ae3d
KO
195 */
196
a6f0788e
CK
197 switch (bio_op(bio)) {
198 case REQ_OP_DISCARD:
199 case REQ_OP_SECURE_ERASE:
a6f0788e 200 case REQ_OP_WRITE_ZEROES:
f9d03f96
CH
201 return 0;
202 case REQ_OP_WRITE_SAME:
8423ae3d 203 return 1;
a6f0788e
CK
204 default:
205 break;
206 }
8423ae3d 207
f4595875 208 bio_for_each_segment(bv, bio, iter)
458b76ed
KO
209 segs++;
210
211 return segs;
212}
213
1da177e4
LT
214/*
215 * get a reference to a bio, so it won't disappear. the intended use is
216 * something like:
217 *
218 * bio_get(bio);
219 * submit_bio(rw, bio);
220 * if (bio->bi_flags ...)
221 * do_something
222 * bio_put(bio);
223 *
224 * without the bio_get(), it could potentially complete I/O before submit_bio
225 * returns. and then bio would be freed memory when if (bio->bi_flags ...)
226 * runs
227 */
dac56212
JA
228static inline void bio_get(struct bio *bio)
229{
230 bio->bi_flags |= (1 << BIO_REFFED);
231 smp_mb__before_atomic();
232 atomic_inc(&bio->__bi_cnt);
233}
234
235static inline void bio_cnt_set(struct bio *bio, unsigned int count)
236{
237 if (count != 1) {
238 bio->bi_flags |= (1 << BIO_REFFED);
239 smp_mb__before_atomic();
240 }
241 atomic_set(&bio->__bi_cnt, count);
242}
1da177e4 243
b7c44ed9
JA
244static inline bool bio_flagged(struct bio *bio, unsigned int bit)
245{
2c68f6dc 246 return (bio->bi_flags & (1U << bit)) != 0;
b7c44ed9
JA
247}
248
249static inline void bio_set_flag(struct bio *bio, unsigned int bit)
250{
2c68f6dc 251 bio->bi_flags |= (1U << bit);
b7c44ed9
JA
252}
253
254static inline void bio_clear_flag(struct bio *bio, unsigned int bit)
255{
2c68f6dc 256 bio->bi_flags &= ~(1U << bit);
b7c44ed9
JA
257}
258
7bcd79ac
ML
259static inline void bio_get_first_bvec(struct bio *bio, struct bio_vec *bv)
260{
261 *bv = bio_iovec(bio);
262}
263
264static inline void bio_get_last_bvec(struct bio *bio, struct bio_vec *bv)
265{
266 struct bvec_iter iter = bio->bi_iter;
267 int idx;
268
7bcd79ac
ML
269 if (unlikely(!bio_multiple_segments(bio))) {
270 *bv = bio_iovec(bio);
271 return;
272 }
273
274 bio_advance_iter(bio, &iter, iter.bi_size);
275
276 if (!iter.bi_bvec_done)
277 idx = iter.bi_idx - 1;
278 else /* in the middle of bvec */
279 idx = iter.bi_idx;
280
281 *bv = bio->bi_io_vec[idx];
282
283 /*
284 * iter.bi_bvec_done records actual length of the last bvec
285 * if this bio ends in the middle of one io vector
286 */
287 if (iter.bi_bvec_done)
288 bv->bv_len = iter.bi_bvec_done;
289}
290
c611529e
MP
291enum bip_flags {
292 BIP_BLOCK_INTEGRITY = 1 << 0, /* block layer owns integrity data */
293 BIP_MAPPED_INTEGRITY = 1 << 1, /* ref tag has been remapped */
294 BIP_CTRL_NOCHECK = 1 << 2, /* disable HBA integrity checking */
295 BIP_DISK_NOCHECK = 1 << 3, /* disable disk integrity checking */
296 BIP_IP_CHECKSUM = 1 << 4, /* IP checksum */
297};
298
7ba1ba12
MP
299/*
300 * bio integrity payload
301 */
302struct bio_integrity_payload {
303 struct bio *bip_bio; /* parent bio */
7ba1ba12 304
d57a5f7c 305 struct bvec_iter bip_iter;
7ba1ba12 306
d57a5f7c 307 bio_end_io_t *bip_end_io; /* saved I/O completion fn */
7ba1ba12 308
7878cba9 309 unsigned short bip_slab; /* slab the bip came from */
7ba1ba12 310 unsigned short bip_vcnt; /* # of integrity bio_vecs */
cbcd1054 311 unsigned short bip_max_vcnt; /* integrity bio_vec slots */
b1f01388 312 unsigned short bip_flags; /* control flags */
7ba1ba12
MP
313
314 struct work_struct bip_work; /* I/O completion */
6fda981c
KO
315
316 struct bio_vec *bip_vec;
317 struct bio_vec bip_inline_vecs[0];/* embedded bvec array */
7ba1ba12 318};
18593088 319
06c1e390
KB
320#if defined(CONFIG_BLK_DEV_INTEGRITY)
321
322static inline struct bio_integrity_payload *bio_integrity(struct bio *bio)
323{
1eff9d32 324 if (bio->bi_opf & REQ_INTEGRITY)
06c1e390
KB
325 return bio->bi_integrity;
326
327 return NULL;
328}
329
c611529e
MP
330static inline bool bio_integrity_flagged(struct bio *bio, enum bip_flags flag)
331{
332 struct bio_integrity_payload *bip = bio_integrity(bio);
333
334 if (bip)
335 return bip->bip_flags & flag;
336
337 return false;
338}
b1f01388 339
18593088
MP
340static inline sector_t bip_get_seed(struct bio_integrity_payload *bip)
341{
342 return bip->bip_iter.bi_sector;
343}
344
345static inline void bip_set_seed(struct bio_integrity_payload *bip,
346 sector_t seed)
347{
348 bip->bip_iter.bi_sector = seed;
349}
350
7ba1ba12 351#endif /* CONFIG_BLK_DEV_INTEGRITY */
1da177e4 352
6678d83f 353extern void bio_trim(struct bio *bio, int offset, int size);
20d0189b
KO
354extern struct bio *bio_split(struct bio *bio, int sectors,
355 gfp_t gfp, struct bio_set *bs);
356
357/**
358 * bio_next_split - get next @sectors from a bio, splitting if necessary
359 * @bio: bio to split
360 * @sectors: number of sectors to split from the front of @bio
361 * @gfp: gfp mask
362 * @bs: bio set to allocate from
363 *
364 * Returns a bio representing the next @sectors of @bio - if the bio is smaller
365 * than @sectors, returns the original bio unchanged.
366 */
367static inline struct bio *bio_next_split(struct bio *bio, int sectors,
368 gfp_t gfp, struct bio_set *bs)
369{
370 if (sectors >= bio_sectors(bio))
371 return bio;
372
373 return bio_split(bio, sectors, gfp, bs);
374}
375
011067b0
N
376extern struct bio_set *bioset_create(unsigned int, unsigned int, int flags);
377enum {
378 BIOSET_NEED_BVECS = BIT(0),
47e0fb46 379 BIOSET_NEED_RESCUER = BIT(1),
011067b0 380};
1da177e4 381extern void bioset_free(struct bio_set *);
a6c39cb4 382extern mempool_t *biovec_create_pool(int pool_entries);
1da177e4 383
7a88fa19 384extern struct bio *bio_alloc_bioset(gfp_t, unsigned int, struct bio_set *);
1da177e4
LT
385extern void bio_put(struct bio *);
386
59d276fe
KO
387extern void __bio_clone_fast(struct bio *, struct bio *);
388extern struct bio *bio_clone_fast(struct bio *, gfp_t, struct bio_set *);
bf800ef1
KO
389extern struct bio *bio_clone_bioset(struct bio *, gfp_t, struct bio_set *bs);
390
3f86a82a
KO
391extern struct bio_set *fs_bio_set;
392
393static inline struct bio *bio_alloc(gfp_t gfp_mask, unsigned int nr_iovecs)
394{
395 return bio_alloc_bioset(gfp_mask, nr_iovecs, fs_bio_set);
396}
397
398static inline struct bio *bio_kmalloc(gfp_t gfp_mask, unsigned int nr_iovecs)
399{
400 return bio_alloc_bioset(gfp_mask, nr_iovecs, NULL);
401}
402
bf800ef1
KO
403static inline struct bio *bio_clone_kmalloc(struct bio *bio, gfp_t gfp_mask)
404{
405 return bio_clone_bioset(bio, gfp_mask, NULL);
406
407}
408
1e3914d4
CH
409extern blk_qc_t submit_bio(struct bio *);
410
4246a0b6
CH
411extern void bio_endio(struct bio *);
412
413static inline void bio_io_error(struct bio *bio)
414{
4e4cbee9 415 bio->bi_status = BLK_STS_IOERR;
4246a0b6
CH
416 bio_endio(bio);
417}
418
1da177e4
LT
419struct request_queue;
420extern int bio_phys_segments(struct request_queue *, struct bio *);
1da177e4 421
4e49ea4a 422extern int submit_bio_wait(struct bio *bio);
054bdf64
KO
423extern void bio_advance(struct bio *, unsigned);
424
3a83f467
ML
425extern void bio_init(struct bio *bio, struct bio_vec *table,
426 unsigned short max_vecs);
f44b48c7 427extern void bio_reset(struct bio *);
196d38bc 428void bio_chain(struct bio *, struct bio *);
1da177e4
LT
429
430extern int bio_add_page(struct bio *, struct page *, unsigned int,unsigned int);
6e68af66
MC
431extern int bio_add_pc_page(struct request_queue *, struct bio *, struct page *,
432 unsigned int, unsigned int);
2cefe4db 433int bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter);
152e283f 434struct rq_map_data;
f1970baf 435extern struct bio *bio_map_user_iov(struct request_queue *,
26e49cfc 436 const struct iov_iter *, gfp_t);
1da177e4 437extern void bio_unmap_user(struct bio *);
df46b9a4 438extern struct bio *bio_map_kern(struct request_queue *, void *, unsigned int,
27496a8c 439 gfp_t);
68154e90
FT
440extern struct bio *bio_copy_kern(struct request_queue *, void *, unsigned int,
441 gfp_t, int);
1da177e4
LT
442extern void bio_set_pages_dirty(struct bio *bio);
443extern void bio_check_pages_dirty(struct bio *bio);
2d4dc890 444
394ffa50
GZ
445void generic_start_io_acct(int rw, unsigned long sectors,
446 struct hd_struct *part);
447void generic_end_io_acct(int rw, struct hd_struct *part,
448 unsigned long start_time);
449
2d4dc890
IL
450#ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
451# error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform"
452#endif
453#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
454extern void bio_flush_dcache_pages(struct bio *bi);
455#else
456static inline void bio_flush_dcache_pages(struct bio *bi)
457{
458}
459#endif
460
16ac3d63 461extern void bio_copy_data(struct bio *dst, struct bio *src);
a0787606 462extern int bio_alloc_pages(struct bio *bio, gfp_t gfp);
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 *,
26e49cfc
KO
467 const struct iov_iter *,
468 gfp_t);
1da177e4
LT
469extern int bio_uncopy_user(struct bio *);
470void zero_fill_bio(struct bio *bio);
9f060e22
KO
471extern struct bio_vec *bvec_alloc(gfp_t, int, unsigned long *, mempool_t *);
472extern void bvec_free(mempool_t *, struct bio_vec *, unsigned int);
7ba1ba12 473extern unsigned int bvec_nr_vecs(unsigned short idx);
51d654e1 474
852c788f 475#ifdef CONFIG_BLK_CGROUP
1d933cf0 476int bio_associate_blkcg(struct bio *bio, struct cgroup_subsys_state *blkcg_css);
852c788f
TH
477int bio_associate_current(struct bio *bio);
478void bio_disassociate_task(struct bio *bio);
20bd723e 479void bio_clone_blkcg_association(struct bio *dst, struct bio *src);
852c788f 480#else /* CONFIG_BLK_CGROUP */
1d933cf0
TH
481static inline int bio_associate_blkcg(struct bio *bio,
482 struct cgroup_subsys_state *blkcg_css) { return 0; }
852c788f
TH
483static inline int bio_associate_current(struct bio *bio) { return -ENOENT; }
484static inline void bio_disassociate_task(struct bio *bio) { }
20bd723e
PV
485static inline void bio_clone_blkcg_association(struct bio *dst,
486 struct bio *src) { }
852c788f
TH
487#endif /* CONFIG_BLK_CGROUP */
488
1da177e4
LT
489#ifdef CONFIG_HIGHMEM
490/*
20b636bf
AB
491 * remember never ever reenable interrupts between a bvec_kmap_irq and
492 * bvec_kunmap_irq!
1da177e4 493 */
4f570f99 494static inline char *bvec_kmap_irq(struct bio_vec *bvec, unsigned long *flags)
1da177e4
LT
495{
496 unsigned long addr;
497
498 /*
499 * might not be a highmem page, but the preempt/irq count
500 * balancing is a lot nicer this way
501 */
502 local_irq_save(*flags);
e8e3c3d6 503 addr = (unsigned long) kmap_atomic(bvec->bv_page);
1da177e4
LT
504
505 BUG_ON(addr & ~PAGE_MASK);
506
507 return (char *) addr + bvec->bv_offset;
508}
509
4f570f99 510static inline void bvec_kunmap_irq(char *buffer, unsigned long *flags)
1da177e4
LT
511{
512 unsigned long ptr = (unsigned long) buffer & PAGE_MASK;
513
e8e3c3d6 514 kunmap_atomic((void *) ptr);
1da177e4
LT
515 local_irq_restore(*flags);
516}
517
518#else
11a691be
GU
519static inline char *bvec_kmap_irq(struct bio_vec *bvec, unsigned long *flags)
520{
521 return page_address(bvec->bv_page) + bvec->bv_offset;
522}
523
524static inline void bvec_kunmap_irq(char *buffer, unsigned long *flags)
525{
526 *flags = 0;
527}
1da177e4
LT
528#endif
529
f619d254 530static inline char *__bio_kmap_irq(struct bio *bio, struct bvec_iter iter,
1da177e4
LT
531 unsigned long *flags)
532{
f619d254 533 return bvec_kmap_irq(&bio_iter_iovec(bio, iter), flags);
1da177e4
LT
534}
535#define __bio_kunmap_irq(buf, flags) bvec_kunmap_irq(buf, flags)
536
537#define bio_kmap_irq(bio, flags) \
f619d254 538 __bio_kmap_irq((bio), (bio)->bi_iter, (flags))
1da177e4
LT
539#define bio_kunmap_irq(buf,flags) __bio_kunmap_irq(buf, flags)
540
8f3d8ba2 541/*
e686307f 542 * BIO list management for use by remapping drivers (e.g. DM or MD) and loop.
8f3d8ba2
CH
543 *
544 * A bio_list anchors a singly-linked list of bios chained through the bi_next
545 * member of the bio. The bio_list also caches the last list member to allow
546 * fast access to the tail.
547 */
548struct bio_list {
549 struct bio *head;
550 struct bio *tail;
551};
552
553static inline int bio_list_empty(const struct bio_list *bl)
554{
555 return bl->head == NULL;
556}
557
558static inline void bio_list_init(struct bio_list *bl)
559{
560 bl->head = bl->tail = NULL;
561}
562
320ae51f
JA
563#define BIO_EMPTY_LIST { NULL, NULL }
564
8f3d8ba2
CH
565#define bio_list_for_each(bio, bl) \
566 for (bio = (bl)->head; bio; bio = bio->bi_next)
567
568static inline unsigned bio_list_size(const struct bio_list *bl)
569{
570 unsigned sz = 0;
571 struct bio *bio;
572
573 bio_list_for_each(bio, bl)
574 sz++;
575
576 return sz;
577}
578
579static inline void bio_list_add(struct bio_list *bl, struct bio *bio)
580{
581 bio->bi_next = NULL;
582
583 if (bl->tail)
584 bl->tail->bi_next = bio;
585 else
586 bl->head = bio;
587
588 bl->tail = bio;
589}
590
591static inline void bio_list_add_head(struct bio_list *bl, struct bio *bio)
592{
593 bio->bi_next = bl->head;
594
595 bl->head = bio;
596
597 if (!bl->tail)
598 bl->tail = bio;
599}
600
601static inline void bio_list_merge(struct bio_list *bl, struct bio_list *bl2)
602{
603 if (!bl2->head)
604 return;
605
606 if (bl->tail)
607 bl->tail->bi_next = bl2->head;
608 else
609 bl->head = bl2->head;
610
611 bl->tail = bl2->tail;
612}
613
614static inline void bio_list_merge_head(struct bio_list *bl,
615 struct bio_list *bl2)
616{
617 if (!bl2->head)
618 return;
619
620 if (bl->head)
621 bl2->tail->bi_next = bl->head;
622 else
623 bl->tail = bl2->tail;
624
625 bl->head = bl2->head;
626}
627
13685a16
GU
628static inline struct bio *bio_list_peek(struct bio_list *bl)
629{
630 return bl->head;
631}
632
8f3d8ba2
CH
633static inline struct bio *bio_list_pop(struct bio_list *bl)
634{
635 struct bio *bio = bl->head;
636
637 if (bio) {
638 bl->head = bl->head->bi_next;
639 if (!bl->head)
640 bl->tail = NULL;
641
642 bio->bi_next = NULL;
643 }
644
645 return bio;
646}
647
648static inline struct bio *bio_list_get(struct bio_list *bl)
649{
650 struct bio *bio = bl->head;
651
652 bl->head = bl->tail = NULL;
653
654 return bio;
655}
656
0ef5a50c
MS
657/*
658 * Increment chain count for the bio. Make sure the CHAIN flag update
659 * is visible before the raised count.
660 */
661static inline void bio_inc_remaining(struct bio *bio)
662{
663 bio_set_flag(bio, BIO_CHAIN);
664 smp_mb__before_atomic();
665 atomic_inc(&bio->__bi_remaining);
666}
667
57fb233f
KO
668/*
669 * bio_set is used to allow other portions of the IO system to
670 * allocate their own private memory pools for bio and iovec structures.
671 * These memory pools in turn all allocate from the bio_slab
672 * and the bvec_slabs[].
673 */
674#define BIO_POOL_SIZE 2
57fb233f
KO
675
676struct bio_set {
677 struct kmem_cache *bio_slab;
678 unsigned int front_pad;
679
680 mempool_t *bio_pool;
9f060e22 681 mempool_t *bvec_pool;
57fb233f
KO
682#if defined(CONFIG_BLK_DEV_INTEGRITY)
683 mempool_t *bio_integrity_pool;
9f060e22 684 mempool_t *bvec_integrity_pool;
57fb233f 685#endif
df2cb6da
KO
686
687 /*
688 * Deadlock avoidance for stacking block drivers: see comments in
689 * bio_alloc_bioset() for details
690 */
691 spinlock_t rescue_lock;
692 struct bio_list rescue_list;
693 struct work_struct rescue_work;
694 struct workqueue_struct *rescue_workqueue;
57fb233f
KO
695};
696
697struct biovec_slab {
698 int nr_vecs;
699 char *name;
700 struct kmem_cache *slab;
701};
702
703/*
704 * a small number of entries is fine, not going to be performance critical.
705 * basically we just need to survive
706 */
707#define BIO_SPLIT_ENTRIES 2
708
7ba1ba12
MP
709#if defined(CONFIG_BLK_DEV_INTEGRITY)
710
d57a5f7c
KO
711#define bip_for_each_vec(bvl, bip, iter) \
712 for_each_bvec(bvl, (bip)->bip_vec, iter, (bip)->bip_iter)
7ba1ba12 713
13f05c8d
MP
714#define bio_for_each_integrity_vec(_bvl, _bio, _iter) \
715 for_each_bio(_bio) \
716 bip_for_each_vec(_bvl, _bio->bi_integrity, _iter)
717
7ba1ba12 718extern struct bio_integrity_payload *bio_integrity_alloc(struct bio *, gfp_t, unsigned int);
1e2a410f 719extern void bio_integrity_free(struct bio *);
7ba1ba12 720extern int bio_integrity_add_page(struct bio *, struct page *, unsigned int, unsigned int);
e7258c1a 721extern bool bio_integrity_enabled(struct bio *bio);
7ba1ba12 722extern int bio_integrity_prep(struct bio *);
4246a0b6 723extern void bio_integrity_endio(struct bio *);
7ba1ba12
MP
724extern void bio_integrity_advance(struct bio *, unsigned int);
725extern void bio_integrity_trim(struct bio *, unsigned int, unsigned int);
1e2a410f 726extern int bio_integrity_clone(struct bio *, struct bio *, gfp_t);
7878cba9
MP
727extern int bioset_integrity_create(struct bio_set *, int);
728extern void bioset_integrity_free(struct bio_set *);
729extern void bio_integrity_init(void);
7ba1ba12
MP
730
731#else /* CONFIG_BLK_DEV_INTEGRITY */
732
c611529e 733static inline void *bio_integrity(struct bio *bio)
6898e3bd 734{
c611529e 735 return NULL;
6898e3bd
MP
736}
737
e7258c1a 738static inline bool bio_integrity_enabled(struct bio *bio)
6898e3bd 739{
e7258c1a 740 return false;
6898e3bd
MP
741}
742
743static inline int bioset_integrity_create(struct bio_set *bs, int pool_size)
744{
745 return 0;
746}
747
748static inline void bioset_integrity_free (struct bio_set *bs)
749{
750 return;
751}
752
753static inline int bio_integrity_prep(struct bio *bio)
754{
755 return 0;
756}
757
1e2a410f 758static inline void bio_integrity_free(struct bio *bio)
6898e3bd
MP
759{
760 return;
761}
762
0c614e2d 763static inline int bio_integrity_clone(struct bio *bio, struct bio *bio_src,
1e2a410f 764 gfp_t gfp_mask)
0c614e2d
SR
765{
766 return 0;
767}
6898e3bd 768
6898e3bd
MP
769static inline void bio_integrity_advance(struct bio *bio,
770 unsigned int bytes_done)
771{
772 return;
773}
774
775static inline void bio_integrity_trim(struct bio *bio, unsigned int offset,
776 unsigned int sectors)
777{
778 return;
779}
780
781static inline void bio_integrity_init(void)
782{
783 return;
784}
7ba1ba12 785
c611529e
MP
786static inline bool bio_integrity_flagged(struct bio *bio, enum bip_flags flag)
787{
788 return false;
789}
790
06c1e390
KB
791static inline void *bio_integrity_alloc(struct bio * bio, gfp_t gfp,
792 unsigned int nr)
793{
794 return ERR_PTR(-EINVAL);
795}
796
797static inline int bio_integrity_add_page(struct bio *bio, struct page *page,
798 unsigned int len, unsigned int offset)
799{
800 return 0;
801}
802
7ba1ba12
MP
803#endif /* CONFIG_BLK_DEV_INTEGRITY */
804
02a5e0ac 805#endif /* CONFIG_BLOCK */
1da177e4 806#endif /* __LINUX_BIO_H */