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Linux 4.7-rc2
[linux-block.git] / include / linux / bio.h
CommitLineData
1da177e4
LT		 1/*
2 * 2.5 block I/O model
3 *
4 * Copyright (C) 2001 Jens Axboe <axboe@suse.de>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
7cc01581 12 *
1da177e4
LT		 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public Licens
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-
19 */
20#ifndef __LINUX_BIO_H
21#define __LINUX_BIO_H
22
23#include <linux/highmem.h>
24#include <linux/mempool.h>
22e2c507 25#include <linux/ioprio.h>
187f1882 26#include <linux/bug.h>
1da177e4 27
02a5e0ac
DH		 28#ifdef CONFIG_BLOCK
29
1da177e4
LT		 30#include <asm/io.h>
31
7cc01581
TH		 32/* struct bio, bio_vec and BIO_* flags are defined in blk_types.h */
33#include <linux/blk_types.h>
34
1da177e4
LT		 35#define BIO_DEBUG
36
37#ifdef BIO_DEBUG
38#define BIO_BUG_ON BUG_ON
39#else
40#define BIO_BUG_ON
41#endif
42
d84a8477 43#define BIO_MAX_PAGES 256
09cbfeaf 44#define BIO_MAX_SIZE (BIO_MAX_PAGES << PAGE_SHIFT)
1da177e4
LT		 45#define BIO_MAX_SECTORS (BIO_MAX_SIZE >> 9)
46
22e2c507
JA		 47/*
48 * upper 16 bits of bi_rw define the io priority of this bio
49 */
50#define BIO_PRIO_SHIFT (8 * sizeof(unsigned long) - IOPRIO_BITS)
51#define bio_prio(bio) ((bio)->bi_rw >> BIO_PRIO_SHIFT)
52#define bio_prio_valid(bio) ioprio_valid(bio_prio(bio))
53
54#define bio_set_prio(bio, prio) do { \
55 WARN_ON(prio >= (1 << IOPRIO_BITS)); \
56 (bio)->bi_rw &= ((1UL << BIO_PRIO_SHIFT) - 1); \
57 (bio)->bi_rw |= ((unsigned long) (prio) << BIO_PRIO_SHIFT); \
58} while (0)
59
1da177e4
LT		 60/*
61 * various member access, note that bio_data should of course not be used
62 * on highmem page vectors
63 */
4550dd6c 64#define __bvec_iter_bvec(bvec, iter) (&(bvec)[(iter).bi_idx])
a4ad39b1 65
4550dd6c
KO		 66#define bvec_iter_page(bvec, iter) \
67 (__bvec_iter_bvec((bvec), (iter))->bv_page)
68
69#define bvec_iter_len(bvec, iter) \
70 min((iter).bi_size, \
71 __bvec_iter_bvec((bvec), (iter))->bv_len - (iter).bi_bvec_done)
72
73#define bvec_iter_offset(bvec, iter) \
74 (__bvec_iter_bvec((bvec), (iter))->bv_offset + (iter).bi_bvec_done)
75
76#define bvec_iter_bvec(bvec, iter) \
77((struct bio_vec) { \
78 .bv_page = bvec_iter_page((bvec), (iter)), \
79 .bv_len = bvec_iter_len((bvec), (iter)), \
80 .bv_offset = bvec_iter_offset((bvec), (iter)), \
81})
82
83#define bio_iter_iovec(bio, iter) \
84 bvec_iter_bvec((bio)->bi_io_vec, (iter))
85
86#define bio_iter_page(bio, iter) \
87 bvec_iter_page((bio)->bi_io_vec, (iter))
88#define bio_iter_len(bio, iter) \
89 bvec_iter_len((bio)->bi_io_vec, (iter))
90#define bio_iter_offset(bio, iter) \
91 bvec_iter_offset((bio)->bi_io_vec, (iter))
92
93#define bio_page(bio) bio_iter_page((bio), (bio)->bi_iter)
94#define bio_offset(bio) bio_iter_offset((bio), (bio)->bi_iter)
95#define bio_iovec(bio) bio_iter_iovec((bio), (bio)->bi_iter)
7988613b 96
458b76ed
KO		 97#define bio_multiple_segments(bio) \
98 ((bio)->bi_iter.bi_size != bio_iovec(bio).bv_len)
4f024f37
KO		 99#define bio_sectors(bio) ((bio)->bi_iter.bi_size >> 9)
100#define bio_end_sector(bio) ((bio)->bi_iter.bi_sector + bio_sectors((bio)))
bf2de6f5 101
458b76ed
KO		 102/*
103 * Check whether this bio carries any data or not. A NULL bio is allowed.
104 */
105static inline bool bio_has_data(struct bio *bio)
106{
107 if (bio &&
108 bio->bi_iter.bi_size &&
109 !(bio->bi_rw & REQ_DISCARD))
110 return true;
111
112 return false;
113}
114
115static inline bool bio_is_rw(struct bio *bio)
116{
117 if (!bio_has_data(bio))
118 return false;
119
120 if (bio->bi_rw & BIO_NO_ADVANCE_ITER_MASK)
121 return false;
122
123 return true;
124}
125
126static inline bool bio_mergeable(struct bio *bio)
127{
128 if (bio->bi_rw & REQ_NOMERGE_FLAGS)
129 return false;
130
131 return true;
132}
133
2e46e8b2 134static inline unsigned int bio_cur_bytes(struct bio *bio)
bf2de6f5 135{
458b76ed 136 if (bio_has_data(bio))
a4ad39b1 137 return bio_iovec(bio).bv_len;
fb2dce86 138 else /* dataless requests such as discard */
4f024f37 139 return bio->bi_iter.bi_size;
bf2de6f5
JA		 140}
141
142static inline void *bio_data(struct bio *bio)
143{
458b76ed 144 if (bio_has_data(bio))
bf2de6f5
JA		 145 return page_address(bio_page(bio)) + bio_offset(bio);
146
147 return NULL;
148}
1da177e4
LT		 149
150/*
151 * will die
152 */
153#define bio_to_phys(bio) (page_to_phys(bio_page((bio))) + (unsigned long) bio_offset((bio)))
154#define bvec_to_phys(bv) (page_to_phys((bv)->bv_page) + (unsigned long) (bv)->bv_offset)
155
156/*
157 * queues that have highmem support enabled may still need to revert to
158 * PIO transfers occasionally and thus map high pages temporarily. For
159 * permanent PIO fall back, user is probably better off disabling highmem
160 * I/O completely on that queue (see ide-dma for example)
161 */
f619d254
KO		 162#define __bio_kmap_atomic(bio, iter) \
163 (kmap_atomic(bio_iter_iovec((bio), (iter)).bv_page) + \
164 bio_iter_iovec((bio), (iter)).bv_offset)
1da177e4 165
f619d254 166#define __bio_kunmap_atomic(addr) kunmap_atomic(addr)
1da177e4
LT		 167
168/*
169 * merge helpers etc
170 */
171
f92131c3
JF		 172/* Default implementation of BIOVEC_PHYS_MERGEABLE */
173#define __BIOVEC_PHYS_MERGEABLE(vec1, vec2) \
174 ((bvec_to_phys((vec1)) + (vec1)->bv_len) == bvec_to_phys((vec2)))
175
1da177e4
LT		 176/*
177 * allow arch override, for eg virtualized architectures (put in asm/io.h)
178 */
179#ifndef BIOVEC_PHYS_MERGEABLE
180#define BIOVEC_PHYS_MERGEABLE(vec1, vec2) \
f92131c3 181 __BIOVEC_PHYS_MERGEABLE(vec1, vec2)
1da177e4
LT		 182#endif
183
1da177e4
LT		 184#define __BIO_SEG_BOUNDARY(addr1, addr2, mask) \
185 (((addr1) | (mask)) == (((addr2) - 1) | (mask)))
186#define BIOVEC_SEG_BOUNDARY(q, b1, b2) \
ae03bf63 187 __BIO_SEG_BOUNDARY(bvec_to_phys((b1)), bvec_to_phys((b2)) + (b2)->bv_len, queue_segment_boundary((q)))
1da177e4 188
d74c6d51
KO		 189/*
190 * drivers should _never_ use the all version - the bio may have been split
191 * before it got to the driver and the driver won't own all of it
192 */
193#define bio_for_each_segment_all(bvl, bio, i) \
f619d254 194 for (i = 0, bvl = (bio)->bi_io_vec; i < (bio)->bi_vcnt; i++, bvl++)
d74c6d51 195
4550dd6c
KO		 196static inline void bvec_iter_advance(struct bio_vec *bv, struct bvec_iter *iter,
197 unsigned bytes)
198{
199 WARN_ONCE(bytes > iter->bi_size,
200 "Attempted to advance past end of bvec iter\n");
201
202 while (bytes) {
203 unsigned len = min(bytes, bvec_iter_len(bv, *iter));
204
205 bytes -= len;
206 iter->bi_size -= len;
207 iter->bi_bvec_done += len;
208
209 if (iter->bi_bvec_done == __bvec_iter_bvec(bv, *iter)->bv_len) {
210 iter->bi_bvec_done = 0;
211 iter->bi_idx++;
212 }
213 }
214}
215
216#define for_each_bvec(bvl, bio_vec, iter, start) \
b7aa84d9
MP		 217 for (iter = (start); \
218 (iter).bi_size && \
219 ((bvl = bvec_iter_bvec((bio_vec), (iter))), 1); \
4550dd6c
KO		 220 bvec_iter_advance((bio_vec), &(iter), (bvl).bv_len))
221
222
223static inline void bio_advance_iter(struct bio *bio, struct bvec_iter *iter,
224 unsigned bytes)
225{
226 iter->bi_sector += bytes >> 9;
227
228 if (bio->bi_rw & BIO_NO_ADVANCE_ITER_MASK)
229 iter->bi_size -= bytes;
230 else
231 bvec_iter_advance(bio->bi_io_vec, iter, bytes);
232}
233
7988613b
KO		 234#define __bio_for_each_segment(bvl, bio, iter, start) \
235 for (iter = (start); \
4550dd6c
KO		 236 (iter).bi_size && \
237 ((bvl = bio_iter_iovec((bio), (iter))), 1); \
238 bio_advance_iter((bio), &(iter), (bvl).bv_len))
7988613b
KO		 239
240#define bio_for_each_segment(bvl, bio, iter) \
241 __bio_for_each_segment(bvl, bio, iter, (bio)->bi_iter)
242
4550dd6c 243#define bio_iter_last(bvec, iter) ((iter).bi_size == (bvec).bv_len)
1da177e4 244
458b76ed
KO		 245static inline unsigned bio_segments(struct bio *bio)
246{
247 unsigned segs = 0;
248 struct bio_vec bv;
249 struct bvec_iter iter;
250
8423ae3d
KO		 251 /*
252 * We special case discard/write same, because they interpret bi_size
253 * differently:
254 */
255
256 if (bio->bi_rw & REQ_DISCARD)
257 return 1;
258
259 if (bio->bi_rw & REQ_WRITE_SAME)
260 return 1;
261
458b76ed
KO		 262 bio_for_each_segment(bv, bio, iter)
263 segs++;
264
265 return segs;
266}
267
1da177e4
LT		 268/*
269 * get a reference to a bio, so it won't disappear. the intended use is
270 * something like:
271 *
272 * bio_get(bio);
273 * submit_bio(rw, bio);
274 * if (bio->bi_flags ...)
275 * do_something
276 * bio_put(bio);
277 *
278 * without the bio_get(), it could potentially complete I/O before submit_bio
279 * returns. and then bio would be freed memory when if (bio->bi_flags ...)
280 * runs
281 */
dac56212
JA		 282static inline void bio_get(struct bio *bio)
283{
284 bio->bi_flags |= (1 << BIO_REFFED);
285 smp_mb__before_atomic();
286 atomic_inc(&bio->__bi_cnt);
287}
288
289static inline void bio_cnt_set(struct bio *bio, unsigned int count)
290{
291 if (count != 1) {
292 bio->bi_flags |= (1 << BIO_REFFED);
293 smp_mb__before_atomic();
294 }
295 atomic_set(&bio->__bi_cnt, count);
296}
1da177e4 297
b7c44ed9
JA		 298static inline bool bio_flagged(struct bio *bio, unsigned int bit)
299{
2c68f6dc 300 return (bio->bi_flags & (1U << bit)) != 0;
b7c44ed9
JA		 301}
302
303static inline void bio_set_flag(struct bio *bio, unsigned int bit)
304{
2c68f6dc 305 bio->bi_flags |= (1U << bit);
b7c44ed9
JA		 306}
307
308static inline void bio_clear_flag(struct bio *bio, unsigned int bit)
309{
2c68f6dc 310 bio->bi_flags &= ~(1U << bit);
b7c44ed9
JA		 311}
312
7bcd79ac
ML		 313static inline void bio_get_first_bvec(struct bio *bio, struct bio_vec *bv)
314{
315 *bv = bio_iovec(bio);
316}
317
318static inline void bio_get_last_bvec(struct bio *bio, struct bio_vec *bv)
319{
320 struct bvec_iter iter = bio->bi_iter;
321 int idx;
322
7bcd79ac
ML		 323 if (unlikely(!bio_multiple_segments(bio))) {
324 *bv = bio_iovec(bio);
325 return;
326 }
327
328 bio_advance_iter(bio, &iter, iter.bi_size);
329
330 if (!iter.bi_bvec_done)
331 idx = iter.bi_idx - 1;
332 else /* in the middle of bvec */
333 idx = iter.bi_idx;
334
335 *bv = bio->bi_io_vec[idx];
336
337 /*
338 * iter.bi_bvec_done records actual length of the last bvec
339 * if this bio ends in the middle of one io vector
340 */
341 if (iter.bi_bvec_done)
342 bv->bv_len = iter.bi_bvec_done;
343}
344
c611529e
MP		 345enum bip_flags {
346 BIP_BLOCK_INTEGRITY = 1 << 0, /* block layer owns integrity data */
347 BIP_MAPPED_INTEGRITY = 1 << 1, /* ref tag has been remapped */
348 BIP_CTRL_NOCHECK = 1 << 2, /* disable HBA integrity checking */
349 BIP_DISK_NOCHECK = 1 << 3, /* disable disk integrity checking */
350 BIP_IP_CHECKSUM = 1 << 4, /* IP checksum */
351};
352
7ba1ba12
MP		 353/*
354 * bio integrity payload
355 */
356struct bio_integrity_payload {
357 struct bio *bip_bio; /* parent bio */
7ba1ba12 358
d57a5f7c 359 struct bvec_iter bip_iter;
7ba1ba12 360
d57a5f7c 361 bio_end_io_t *bip_end_io; /* saved I/O completion fn */
7ba1ba12 362
7878cba9 363 unsigned short bip_slab; /* slab the bip came from */
7ba1ba12 364 unsigned short bip_vcnt; /* # of integrity bio_vecs */
cbcd1054 365 unsigned short bip_max_vcnt; /* integrity bio_vec slots */
b1f01388 366 unsigned short bip_flags; /* control flags */
7ba1ba12
MP		 367
368 struct work_struct bip_work; /* I/O completion */
6fda981c
KO		 369
370 struct bio_vec *bip_vec;
371 struct bio_vec bip_inline_vecs[0];/* embedded bvec array */
7ba1ba12 372};
18593088 373
06c1e390
KB		 374#if defined(CONFIG_BLK_DEV_INTEGRITY)
375
376static inline struct bio_integrity_payload *bio_integrity(struct bio *bio)
377{
378 if (bio->bi_rw & REQ_INTEGRITY)
379 return bio->bi_integrity;
380
381 return NULL;
382}
383
c611529e
MP		 384static inline bool bio_integrity_flagged(struct bio *bio, enum bip_flags flag)
385{
386 struct bio_integrity_payload *bip = bio_integrity(bio);
387
388 if (bip)
389 return bip->bip_flags & flag;
390
391 return false;
392}
b1f01388 393
18593088
MP		 394static inline sector_t bip_get_seed(struct bio_integrity_payload *bip)
395{
396 return bip->bip_iter.bi_sector;
397}
398
399static inline void bip_set_seed(struct bio_integrity_payload *bip,
400 sector_t seed)
401{
402 bip->bip_iter.bi_sector = seed;
403}
404
7ba1ba12 405#endif /* CONFIG_BLK_DEV_INTEGRITY */
1da177e4 406
6678d83f 407extern void bio_trim(struct bio *bio, int offset, int size);
20d0189b
KO		 408extern struct bio *bio_split(struct bio *bio, int sectors,
409 gfp_t gfp, struct bio_set *bs);
410
411/**
412 * bio_next_split - get next @sectors from a bio, splitting if necessary
413 * @bio: bio to split
414 * @sectors: number of sectors to split from the front of @bio
415 * @gfp: gfp mask
416 * @bs: bio set to allocate from
417 *
418 * Returns a bio representing the next @sectors of @bio - if the bio is smaller
419 * than @sectors, returns the original bio unchanged.
420 */
421static inline struct bio *bio_next_split(struct bio *bio, int sectors,
422 gfp_t gfp, struct bio_set *bs)
423{
424 if (sectors >= bio_sectors(bio))
425 return bio;
426
427 return bio_split(bio, sectors, gfp, bs);
428}
429
bb799ca0 430extern struct bio_set *bioset_create(unsigned int, unsigned int);
d8f429e1 431extern struct bio_set *bioset_create_nobvec(unsigned int, unsigned int);
1da177e4 432extern void bioset_free(struct bio_set *);
a6c39cb4 433extern mempool_t *biovec_create_pool(int pool_entries);
1da177e4 434
dd0fc66f 435extern struct bio *bio_alloc_bioset(gfp_t, int, struct bio_set *);
1da177e4
LT		 436extern void bio_put(struct bio *);
437
59d276fe
KO		 438extern void __bio_clone_fast(struct bio *, struct bio *);
439extern struct bio *bio_clone_fast(struct bio *, gfp_t, struct bio_set *);
bf800ef1
KO		 440extern struct bio *bio_clone_bioset(struct bio *, gfp_t, struct bio_set *bs);
441
3f86a82a
KO		 442extern struct bio_set *fs_bio_set;
443
444static inline struct bio *bio_alloc(gfp_t gfp_mask, unsigned int nr_iovecs)
445{
446 return bio_alloc_bioset(gfp_mask, nr_iovecs, fs_bio_set);
447}
448
bf800ef1
KO		 449static inline struct bio *bio_clone(struct bio *bio, gfp_t gfp_mask)
450{
451 return bio_clone_bioset(bio, gfp_mask, fs_bio_set);
452}
453
3f86a82a
KO		 454static inline struct bio *bio_kmalloc(gfp_t gfp_mask, unsigned int nr_iovecs)
455{
456 return bio_alloc_bioset(gfp_mask, nr_iovecs, NULL);
457}
458
bf800ef1
KO		 459static inline struct bio *bio_clone_kmalloc(struct bio *bio, gfp_t gfp_mask)
460{
461 return bio_clone_bioset(bio, gfp_mask, NULL);
462
463}
464
4246a0b6
CH		 465extern void bio_endio(struct bio *);
466
467static inline void bio_io_error(struct bio *bio)
468{
469 bio->bi_error = -EIO;
470 bio_endio(bio);
471}
472
1da177e4
LT		 473struct request_queue;
474extern int bio_phys_segments(struct request_queue *, struct bio *);
1da177e4 475
9e882242 476extern int submit_bio_wait(int rw, struct bio *bio);
054bdf64
KO		 477extern void bio_advance(struct bio *, unsigned);
478
1da177e4 479extern void bio_init(struct bio *);
f44b48c7 480extern void bio_reset(struct bio *);
196d38bc 481void bio_chain(struct bio *, struct bio *);
1da177e4
LT		 482
483extern int bio_add_page(struct bio *, struct page *, unsigned int,unsigned int);
6e68af66
MC		 484extern int bio_add_pc_page(struct request_queue *, struct bio *, struct page *,
485 unsigned int, unsigned int);
152e283f 486struct rq_map_data;
f1970baf 487extern struct bio *bio_map_user_iov(struct request_queue *,
26e49cfc 488 const struct iov_iter *, gfp_t);
1da177e4 489extern void bio_unmap_user(struct bio *);
df46b9a4 490extern struct bio *bio_map_kern(struct request_queue *, void *, unsigned int,
27496a8c 491 gfp_t);
68154e90
FT		 492extern struct bio *bio_copy_kern(struct request_queue *, void *, unsigned int,
493 gfp_t, int);
1da177e4
LT		 494extern void bio_set_pages_dirty(struct bio *bio);
495extern void bio_check_pages_dirty(struct bio *bio);
2d4dc890 496
394ffa50
GZ		 497void generic_start_io_acct(int rw, unsigned long sectors,
498 struct hd_struct *part);
499void generic_end_io_acct(int rw, struct hd_struct *part,
500 unsigned long start_time);
501
2d4dc890
IL		 502#ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
503# error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform"
504#endif
505#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
506extern void bio_flush_dcache_pages(struct bio *bi);
507#else
508static inline void bio_flush_dcache_pages(struct bio *bi)
509{
510}
511#endif
512
16ac3d63 513extern void bio_copy_data(struct bio *dst, struct bio *src);
a0787606 514extern int bio_alloc_pages(struct bio *bio, gfp_t gfp);
16ac3d63 515
152e283f 516extern struct bio *bio_copy_user_iov(struct request_queue *,
86d564c8 517 struct rq_map_data *,
26e49cfc
KO		 518 const struct iov_iter *,
519 gfp_t);
1da177e4
LT		 520extern int bio_uncopy_user(struct bio *);
521void zero_fill_bio(struct bio *bio);
9f060e22
KO		 522extern struct bio_vec *bvec_alloc(gfp_t, int, unsigned long *, mempool_t *);
523extern void bvec_free(mempool_t *, struct bio_vec *, unsigned int);
7ba1ba12 524extern unsigned int bvec_nr_vecs(unsigned short idx);
51d654e1 525
852c788f 526#ifdef CONFIG_BLK_CGROUP
1d933cf0 527int bio_associate_blkcg(struct bio *bio, struct cgroup_subsys_state *blkcg_css);
852c788f
TH		 528int bio_associate_current(struct bio *bio);
529void bio_disassociate_task(struct bio *bio);
530#else /* CONFIG_BLK_CGROUP */
1d933cf0
TH		 531static inline int bio_associate_blkcg(struct bio *bio,
532 struct cgroup_subsys_state *blkcg_css) { return 0; }
852c788f
TH		 533static inline int bio_associate_current(struct bio *bio) { return -ENOENT; }
534static inline void bio_disassociate_task(struct bio *bio) { }
535#endif /* CONFIG_BLK_CGROUP */
536
1da177e4
LT		 537#ifdef CONFIG_HIGHMEM
538/*
20b636bf
AB		 539 * remember never ever reenable interrupts between a bvec_kmap_irq and
540 * bvec_kunmap_irq!
1da177e4 541 */
4f570f99 542static inline char *bvec_kmap_irq(struct bio_vec *bvec, unsigned long *flags)
1da177e4
LT		 543{
544 unsigned long addr;
545
546 /*
547 * might not be a highmem page, but the preempt/irq count
548 * balancing is a lot nicer this way
549 */
550 local_irq_save(*flags);
e8e3c3d6 551 addr = (unsigned long) kmap_atomic(bvec->bv_page);
1da177e4
LT		 552
553 BUG_ON(addr & ~PAGE_MASK);
554
555 return (char *) addr + bvec->bv_offset;
556}
557
4f570f99 558static inline void bvec_kunmap_irq(char *buffer, unsigned long *flags)
1da177e4
LT		 559{
560 unsigned long ptr = (unsigned long) buffer & PAGE_MASK;
561
e8e3c3d6 562 kunmap_atomic((void *) ptr);
1da177e4
LT		 563 local_irq_restore(*flags);
564}
565
566#else
11a691be
GU		 567static inline char *bvec_kmap_irq(struct bio_vec *bvec, unsigned long *flags)
568{
569 return page_address(bvec->bv_page) + bvec->bv_offset;
570}
571
572static inline void bvec_kunmap_irq(char *buffer, unsigned long *flags)
573{
574 *flags = 0;
575}
1da177e4
LT		 576#endif
577
f619d254 578static inline char *__bio_kmap_irq(struct bio *bio, struct bvec_iter iter,
1da177e4
LT		 579 unsigned long *flags)
580{
f619d254 581 return bvec_kmap_irq(&bio_iter_iovec(bio, iter), flags);
1da177e4
LT		 582}
583#define __bio_kunmap_irq(buf, flags) bvec_kunmap_irq(buf, flags)
584
585#define bio_kmap_irq(bio, flags) \
f619d254 586 __bio_kmap_irq((bio), (bio)->bi_iter, (flags))
1da177e4
LT		 587#define bio_kunmap_irq(buf,flags) __bio_kunmap_irq(buf, flags)
588
8f3d8ba2 589/*
e686307f 590 * BIO list management for use by remapping drivers (e.g. DM or MD) and loop.
8f3d8ba2
CH		 591 *
592 * A bio_list anchors a singly-linked list of bios chained through the bi_next
593 * member of the bio. The bio_list also caches the last list member to allow
594 * fast access to the tail.
595 */
596struct bio_list {
597 struct bio *head;
598 struct bio *tail;
599};
600
601static inline int bio_list_empty(const struct bio_list *bl)
602{
603 return bl->head == NULL;
604}
605
606static inline void bio_list_init(struct bio_list *bl)
607{
608 bl->head = bl->tail = NULL;
609}
610
320ae51f
JA		 611#define BIO_EMPTY_LIST { NULL, NULL }
612
8f3d8ba2
CH		 613#define bio_list_for_each(bio, bl) \
614 for (bio = (bl)->head; bio; bio = bio->bi_next)
615
616static inline unsigned bio_list_size(const struct bio_list *bl)
617{
618 unsigned sz = 0;
619 struct bio *bio;
620
621 bio_list_for_each(bio, bl)
622 sz++;
623
624 return sz;
625}
626
627static inline void bio_list_add(struct bio_list *bl, struct bio *bio)
628{
629 bio->bi_next = NULL;
630
631 if (bl->tail)
632 bl->tail->bi_next = bio;
633 else
634 bl->head = bio;
635
636 bl->tail = bio;
637}
638
639static inline void bio_list_add_head(struct bio_list *bl, struct bio *bio)
640{
641 bio->bi_next = bl->head;
642
643 bl->head = bio;
644
645 if (!bl->tail)
646 bl->tail = bio;
647}
648
649static inline void bio_list_merge(struct bio_list *bl, struct bio_list *bl2)
650{
651 if (!bl2->head)
652 return;
653
654 if (bl->tail)
655 bl->tail->bi_next = bl2->head;
656 else
657 bl->head = bl2->head;
658
659 bl->tail = bl2->tail;
660}
661
662static inline void bio_list_merge_head(struct bio_list *bl,
663 struct bio_list *bl2)
664{
665 if (!bl2->head)
666 return;
667
668 if (bl->head)
669 bl2->tail->bi_next = bl->head;
670 else
671 bl->tail = bl2->tail;
672
673 bl->head = bl2->head;
674}
675
13685a16
GU		 676static inline struct bio *bio_list_peek(struct bio_list *bl)
677{
678 return bl->head;
679}
680
8f3d8ba2
CH		 681static inline struct bio *bio_list_pop(struct bio_list *bl)
682{
683 struct bio *bio = bl->head;
684
685 if (bio) {
686 bl->head = bl->head->bi_next;
687 if (!bl->head)
688 bl->tail = NULL;
689
690 bio->bi_next = NULL;
691 }
692
693 return bio;
694}
695
696static inline struct bio *bio_list_get(struct bio_list *bl)
697{
698 struct bio *bio = bl->head;
699
700 bl->head = bl->tail = NULL;
701
702 return bio;
703}
704
0ef5a50c
MS		 705/*
706 * Increment chain count for the bio. Make sure the CHAIN flag update
707 * is visible before the raised count.
708 */
709static inline void bio_inc_remaining(struct bio *bio)
710{
711 bio_set_flag(bio, BIO_CHAIN);
712 smp_mb__before_atomic();
713 atomic_inc(&bio->__bi_remaining);
714}
715
57fb233f
KO		 716/*
717 * bio_set is used to allow other portions of the IO system to
718 * allocate their own private memory pools for bio and iovec structures.
719 * These memory pools in turn all allocate from the bio_slab
720 * and the bvec_slabs[].
721 */
722#define BIO_POOL_SIZE 2
723#define BIOVEC_NR_POOLS 6
724#define BIOVEC_MAX_IDX (BIOVEC_NR_POOLS - 1)
725
726struct bio_set {
727 struct kmem_cache *bio_slab;
728 unsigned int front_pad;
729
730 mempool_t *bio_pool;
9f060e22 731 mempool_t *bvec_pool;
57fb233f
KO		 732#if defined(CONFIG_BLK_DEV_INTEGRITY)
733 mempool_t *bio_integrity_pool;
9f060e22 734 mempool_t *bvec_integrity_pool;
57fb233f 735#endif
df2cb6da
KO		 736
737 /*
738 * Deadlock avoidance for stacking block drivers: see comments in
739 * bio_alloc_bioset() for details
740 */
741 spinlock_t rescue_lock;
742 struct bio_list rescue_list;
743 struct work_struct rescue_work;
744 struct workqueue_struct *rescue_workqueue;
57fb233f
KO		 745};
746
747struct biovec_slab {
748 int nr_vecs;
749 char *name;
750 struct kmem_cache *slab;
751};
752
753/*
754 * a small number of entries is fine, not going to be performance critical.
755 * basically we just need to survive
756 */
757#define BIO_SPLIT_ENTRIES 2
758
7ba1ba12
MP		 759#if defined(CONFIG_BLK_DEV_INTEGRITY)
760
d57a5f7c
KO		 761#define bip_for_each_vec(bvl, bip, iter) \
762 for_each_bvec(bvl, (bip)->bip_vec, iter, (bip)->bip_iter)
7ba1ba12 763
13f05c8d
MP		 764#define bio_for_each_integrity_vec(_bvl, _bio, _iter) \
765 for_each_bio(_bio) \
766 bip_for_each_vec(_bvl, _bio->bi_integrity, _iter)
767
7ba1ba12 768extern struct bio_integrity_payload *bio_integrity_alloc(struct bio *, gfp_t, unsigned int);
1e2a410f 769extern void bio_integrity_free(struct bio *);
7ba1ba12 770extern int bio_integrity_add_page(struct bio *, struct page *, unsigned int, unsigned int);
e7258c1a 771extern bool bio_integrity_enabled(struct bio *bio);
7ba1ba12 772extern int bio_integrity_prep(struct bio *);
4246a0b6 773extern void bio_integrity_endio(struct bio *);
7ba1ba12
MP		 774extern void bio_integrity_advance(struct bio *, unsigned int);
775extern void bio_integrity_trim(struct bio *, unsigned int, unsigned int);
1e2a410f 776extern int bio_integrity_clone(struct bio *, struct bio *, gfp_t);
7878cba9
MP		 777extern int bioset_integrity_create(struct bio_set *, int);
778extern void bioset_integrity_free(struct bio_set *);
779extern void bio_integrity_init(void);
7ba1ba12
MP		 780
781#else /* CONFIG_BLK_DEV_INTEGRITY */
782
c611529e 783static inline void *bio_integrity(struct bio *bio)
6898e3bd 784{
c611529e 785 return NULL;
6898e3bd
MP		 786}
787
e7258c1a 788static inline bool bio_integrity_enabled(struct bio *bio)
6898e3bd 789{
e7258c1a 790 return false;
6898e3bd
MP		 791}
792
793static inline int bioset_integrity_create(struct bio_set *bs, int pool_size)
794{
795 return 0;
796}
797
798static inline void bioset_integrity_free (struct bio_set *bs)
799{
800 return;
801}
802
803static inline int bio_integrity_prep(struct bio *bio)
804{
805 return 0;
806}
807
1e2a410f 808static inline void bio_integrity_free(struct bio *bio)
6898e3bd
MP		 809{
810 return;
811}
812
0c614e2d 813static inline int bio_integrity_clone(struct bio *bio, struct bio *bio_src,
1e2a410f 814 gfp_t gfp_mask)
0c614e2d
SR		 815{
816 return 0;
817}
6898e3bd 818
6898e3bd
MP		 819static inline void bio_integrity_advance(struct bio *bio,
820 unsigned int bytes_done)
821{
822 return;
823}
824
825static inline void bio_integrity_trim(struct bio *bio, unsigned int offset,
826 unsigned int sectors)
827{
828 return;
829}
830
831static inline void bio_integrity_init(void)
832{
833 return;
834}
7ba1ba12 835
c611529e
MP		 836static inline bool bio_integrity_flagged(struct bio *bio, enum bip_flags flag)
837{
838 return false;
839}
840
06c1e390
KB		 841static inline void *bio_integrity_alloc(struct bio * bio, gfp_t gfp,
842 unsigned int nr)
843{
844 return ERR_PTR(-EINVAL);
845}
846
847static inline int bio_integrity_add_page(struct bio *bio, struct page *page,
848 unsigned int len, unsigned int offset)
849{
850 return 0;
851}
852
7ba1ba12
MP		 853#endif /* CONFIG_BLK_DEV_INTEGRITY */
854
02a5e0ac 855#endif /* CONFIG_BLOCK */
1da177e4 856#endif /* __LINUX_BIO_H */
Linux 6.x block layer and io_uring tree(s)