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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
1da177e4
LT
44#define BIO_MAX_SIZE (BIO_MAX_PAGES << PAGE_CACHE_SHIFT)
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
66cb45aa
JA
189/*
190 * Check if adding a bio_vec after bprv with offset would create a gap in
191 * the SG list. Most drivers don't care about this, but some do.
192 */
193static inline bool bvec_gap_to_prev(struct bio_vec *bprv, unsigned int offset)
194{
195 return offset || ((bprv->bv_offset + bprv->bv_len) & (PAGE_SIZE - 1));
196}
197
6712ecf8 198#define bio_io_error(bio) bio_endio((bio), -EIO)
1da177e4 199
d74c6d51
KO
200/*
201 * drivers should _never_ use the all version - the bio may have been split
202 * before it got to the driver and the driver won't own all of it
203 */
204#define bio_for_each_segment_all(bvl, bio, i) \
f619d254 205 for (i = 0, bvl = (bio)->bi_io_vec; i < (bio)->bi_vcnt; i++, bvl++)
d74c6d51 206
4550dd6c
KO
207static inline void bvec_iter_advance(struct bio_vec *bv, struct bvec_iter *iter,
208 unsigned bytes)
209{
210 WARN_ONCE(bytes > iter->bi_size,
211 "Attempted to advance past end of bvec iter\n");
212
213 while (bytes) {
214 unsigned len = min(bytes, bvec_iter_len(bv, *iter));
215
216 bytes -= len;
217 iter->bi_size -= len;
218 iter->bi_bvec_done += len;
219
220 if (iter->bi_bvec_done == __bvec_iter_bvec(bv, *iter)->bv_len) {
221 iter->bi_bvec_done = 0;
222 iter->bi_idx++;
223 }
224 }
225}
226
227#define for_each_bvec(bvl, bio_vec, iter, start) \
b7aa84d9
MP
228 for (iter = (start); \
229 (iter).bi_size && \
230 ((bvl = bvec_iter_bvec((bio_vec), (iter))), 1); \
4550dd6c
KO
231 bvec_iter_advance((bio_vec), &(iter), (bvl).bv_len))
232
233
234static inline void bio_advance_iter(struct bio *bio, struct bvec_iter *iter,
235 unsigned bytes)
236{
237 iter->bi_sector += bytes >> 9;
238
239 if (bio->bi_rw & BIO_NO_ADVANCE_ITER_MASK)
240 iter->bi_size -= bytes;
241 else
242 bvec_iter_advance(bio->bi_io_vec, iter, bytes);
243}
244
7988613b
KO
245#define __bio_for_each_segment(bvl, bio, iter, start) \
246 for (iter = (start); \
4550dd6c
KO
247 (iter).bi_size && \
248 ((bvl = bio_iter_iovec((bio), (iter))), 1); \
249 bio_advance_iter((bio), &(iter), (bvl).bv_len))
7988613b
KO
250
251#define bio_for_each_segment(bvl, bio, iter) \
252 __bio_for_each_segment(bvl, bio, iter, (bio)->bi_iter)
253
4550dd6c 254#define bio_iter_last(bvec, iter) ((iter).bi_size == (bvec).bv_len)
1da177e4 255
458b76ed
KO
256static inline unsigned bio_segments(struct bio *bio)
257{
258 unsigned segs = 0;
259 struct bio_vec bv;
260 struct bvec_iter iter;
261
8423ae3d
KO
262 /*
263 * We special case discard/write same, because they interpret bi_size
264 * differently:
265 */
266
267 if (bio->bi_rw & REQ_DISCARD)
268 return 1;
269
270 if (bio->bi_rw & REQ_WRITE_SAME)
271 return 1;
272
458b76ed
KO
273 bio_for_each_segment(bv, bio, iter)
274 segs++;
275
276 return segs;
277}
278
1da177e4
LT
279/*
280 * get a reference to a bio, so it won't disappear. the intended use is
281 * something like:
282 *
283 * bio_get(bio);
284 * submit_bio(rw, bio);
285 * if (bio->bi_flags ...)
286 * do_something
287 * bio_put(bio);
288 *
289 * without the bio_get(), it could potentially complete I/O before submit_bio
290 * returns. and then bio would be freed memory when if (bio->bi_flags ...)
291 * runs
292 */
dac56212
JA
293static inline void bio_get(struct bio *bio)
294{
295 bio->bi_flags |= (1 << BIO_REFFED);
296 smp_mb__before_atomic();
297 atomic_inc(&bio->__bi_cnt);
298}
299
300static inline void bio_cnt_set(struct bio *bio, unsigned int count)
301{
302 if (count != 1) {
303 bio->bi_flags |= (1 << BIO_REFFED);
304 smp_mb__before_atomic();
305 }
306 atomic_set(&bio->__bi_cnt, count);
307}
1da177e4 308
c611529e
MP
309enum bip_flags {
310 BIP_BLOCK_INTEGRITY = 1 << 0, /* block layer owns integrity data */
311 BIP_MAPPED_INTEGRITY = 1 << 1, /* ref tag has been remapped */
312 BIP_CTRL_NOCHECK = 1 << 2, /* disable HBA integrity checking */
313 BIP_DISK_NOCHECK = 1 << 3, /* disable disk integrity checking */
314 BIP_IP_CHECKSUM = 1 << 4, /* IP checksum */
315};
316
7ba1ba12 317#if defined(CONFIG_BLK_DEV_INTEGRITY)
180b2f95
MP
318
319static inline struct bio_integrity_payload *bio_integrity(struct bio *bio)
320{
321 if (bio->bi_rw & REQ_INTEGRITY)
322 return bio->bi_integrity;
323
324 return NULL;
325}
326
7ba1ba12
MP
327/*
328 * bio integrity payload
329 */
330struct bio_integrity_payload {
331 struct bio *bip_bio; /* parent bio */
7ba1ba12 332
d57a5f7c 333 struct bvec_iter bip_iter;
7ba1ba12 334
d57a5f7c 335 bio_end_io_t *bip_end_io; /* saved I/O completion fn */
7ba1ba12 336
7878cba9 337 unsigned short bip_slab; /* slab the bip came from */
7ba1ba12 338 unsigned short bip_vcnt; /* # of integrity bio_vecs */
cbcd1054 339 unsigned short bip_max_vcnt; /* integrity bio_vec slots */
b1f01388 340 unsigned short bip_flags; /* control flags */
7ba1ba12
MP
341
342 struct work_struct bip_work; /* I/O completion */
6fda981c
KO
343
344 struct bio_vec *bip_vec;
345 struct bio_vec bip_inline_vecs[0];/* embedded bvec array */
7ba1ba12 346};
18593088 347
c611529e
MP
348static inline bool bio_integrity_flagged(struct bio *bio, enum bip_flags flag)
349{
350 struct bio_integrity_payload *bip = bio_integrity(bio);
351
352 if (bip)
353 return bip->bip_flags & flag;
354
355 return false;
356}
b1f01388 357
18593088
MP
358static inline sector_t bip_get_seed(struct bio_integrity_payload *bip)
359{
360 return bip->bip_iter.bi_sector;
361}
362
363static inline void bip_set_seed(struct bio_integrity_payload *bip,
364 sector_t seed)
365{
366 bip->bip_iter.bi_sector = seed;
367}
368
7ba1ba12 369#endif /* CONFIG_BLK_DEV_INTEGRITY */
1da177e4 370
6678d83f 371extern void bio_trim(struct bio *bio, int offset, int size);
20d0189b
KO
372extern struct bio *bio_split(struct bio *bio, int sectors,
373 gfp_t gfp, struct bio_set *bs);
374
375/**
376 * bio_next_split - get next @sectors from a bio, splitting if necessary
377 * @bio: bio to split
378 * @sectors: number of sectors to split from the front of @bio
379 * @gfp: gfp mask
380 * @bs: bio set to allocate from
381 *
382 * Returns a bio representing the next @sectors of @bio - if the bio is smaller
383 * than @sectors, returns the original bio unchanged.
384 */
385static inline struct bio *bio_next_split(struct bio *bio, int sectors,
386 gfp_t gfp, struct bio_set *bs)
387{
388 if (sectors >= bio_sectors(bio))
389 return bio;
390
391 return bio_split(bio, sectors, gfp, bs);
392}
393
bb799ca0 394extern struct bio_set *bioset_create(unsigned int, unsigned int);
d8f429e1 395extern struct bio_set *bioset_create_nobvec(unsigned int, unsigned int);
1da177e4 396extern void bioset_free(struct bio_set *);
a6c39cb4 397extern mempool_t *biovec_create_pool(int pool_entries);
1da177e4 398
dd0fc66f 399extern struct bio *bio_alloc_bioset(gfp_t, int, struct bio_set *);
1da177e4
LT
400extern void bio_put(struct bio *);
401
59d276fe
KO
402extern void __bio_clone_fast(struct bio *, struct bio *);
403extern struct bio *bio_clone_fast(struct bio *, gfp_t, struct bio_set *);
bf800ef1
KO
404extern struct bio *bio_clone_bioset(struct bio *, gfp_t, struct bio_set *bs);
405
3f86a82a
KO
406extern struct bio_set *fs_bio_set;
407
408static inline struct bio *bio_alloc(gfp_t gfp_mask, unsigned int nr_iovecs)
409{
410 return bio_alloc_bioset(gfp_mask, nr_iovecs, fs_bio_set);
411}
412
bf800ef1
KO
413static inline struct bio *bio_clone(struct bio *bio, gfp_t gfp_mask)
414{
415 return bio_clone_bioset(bio, gfp_mask, fs_bio_set);
416}
417
3f86a82a
KO
418static inline struct bio *bio_kmalloc(gfp_t gfp_mask, unsigned int nr_iovecs)
419{
420 return bio_alloc_bioset(gfp_mask, nr_iovecs, NULL);
421}
422
bf800ef1
KO
423static inline struct bio *bio_clone_kmalloc(struct bio *bio, gfp_t gfp_mask)
424{
425 return bio_clone_bioset(bio, gfp_mask, NULL);
426
427}
428
6712ecf8 429extern void bio_endio(struct bio *, int);
1da177e4
LT
430struct request_queue;
431extern int bio_phys_segments(struct request_queue *, struct bio *);
1da177e4 432
9e882242 433extern int submit_bio_wait(int rw, struct bio *bio);
054bdf64
KO
434extern void bio_advance(struct bio *, unsigned);
435
1da177e4 436extern void bio_init(struct bio *);
f44b48c7 437extern void bio_reset(struct bio *);
196d38bc 438void bio_chain(struct bio *, struct bio *);
1da177e4
LT
439
440extern int bio_add_page(struct bio *, struct page *, unsigned int,unsigned int);
6e68af66
MC
441extern int bio_add_pc_page(struct request_queue *, struct bio *, struct page *,
442 unsigned int, unsigned int);
1da177e4 443extern int bio_get_nr_vecs(struct block_device *);
152e283f 444struct rq_map_data;
f1970baf 445extern struct bio *bio_map_user_iov(struct request_queue *,
26e49cfc 446 const struct iov_iter *, gfp_t);
1da177e4 447extern void bio_unmap_user(struct bio *);
df46b9a4 448extern struct bio *bio_map_kern(struct request_queue *, void *, unsigned int,
27496a8c 449 gfp_t);
68154e90
FT
450extern struct bio *bio_copy_kern(struct request_queue *, void *, unsigned int,
451 gfp_t, int);
1da177e4
LT
452extern void bio_set_pages_dirty(struct bio *bio);
453extern void bio_check_pages_dirty(struct bio *bio);
2d4dc890 454
394ffa50
GZ
455void generic_start_io_acct(int rw, unsigned long sectors,
456 struct hd_struct *part);
457void generic_end_io_acct(int rw, struct hd_struct *part,
458 unsigned long start_time);
459
2d4dc890
IL
460#ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
461# error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform"
462#endif
463#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
464extern void bio_flush_dcache_pages(struct bio *bi);
465#else
466static inline void bio_flush_dcache_pages(struct bio *bi)
467{
468}
469#endif
470
16ac3d63 471extern void bio_copy_data(struct bio *dst, struct bio *src);
a0787606 472extern int bio_alloc_pages(struct bio *bio, gfp_t gfp);
16ac3d63 473
152e283f 474extern struct bio *bio_copy_user_iov(struct request_queue *,
86d564c8 475 struct rq_map_data *,
26e49cfc
KO
476 const struct iov_iter *,
477 gfp_t);
1da177e4
LT
478extern int bio_uncopy_user(struct bio *);
479void zero_fill_bio(struct bio *bio);
9f060e22
KO
480extern struct bio_vec *bvec_alloc(gfp_t, int, unsigned long *, mempool_t *);
481extern void bvec_free(mempool_t *, struct bio_vec *, unsigned int);
7ba1ba12 482extern unsigned int bvec_nr_vecs(unsigned short idx);
51d654e1 483
852c788f 484#ifdef CONFIG_BLK_CGROUP
1d933cf0 485int bio_associate_blkcg(struct bio *bio, struct cgroup_subsys_state *blkcg_css);
852c788f
TH
486int bio_associate_current(struct bio *bio);
487void bio_disassociate_task(struct bio *bio);
488#else /* CONFIG_BLK_CGROUP */
1d933cf0
TH
489static inline int bio_associate_blkcg(struct bio *bio,
490 struct cgroup_subsys_state *blkcg_css) { return 0; }
852c788f
TH
491static inline int bio_associate_current(struct bio *bio) { return -ENOENT; }
492static inline void bio_disassociate_task(struct bio *bio) { }
493#endif /* CONFIG_BLK_CGROUP */
494
1da177e4
LT
495#ifdef CONFIG_HIGHMEM
496/*
20b636bf
AB
497 * remember never ever reenable interrupts between a bvec_kmap_irq and
498 * bvec_kunmap_irq!
1da177e4 499 */
4f570f99 500static inline char *bvec_kmap_irq(struct bio_vec *bvec, unsigned long *flags)
1da177e4
LT
501{
502 unsigned long addr;
503
504 /*
505 * might not be a highmem page, but the preempt/irq count
506 * balancing is a lot nicer this way
507 */
508 local_irq_save(*flags);
e8e3c3d6 509 addr = (unsigned long) kmap_atomic(bvec->bv_page);
1da177e4
LT
510
511 BUG_ON(addr & ~PAGE_MASK);
512
513 return (char *) addr + bvec->bv_offset;
514}
515
4f570f99 516static inline void bvec_kunmap_irq(char *buffer, unsigned long *flags)
1da177e4
LT
517{
518 unsigned long ptr = (unsigned long) buffer & PAGE_MASK;
519
e8e3c3d6 520 kunmap_atomic((void *) ptr);
1da177e4
LT
521 local_irq_restore(*flags);
522}
523
524#else
11a691be
GU
525static inline char *bvec_kmap_irq(struct bio_vec *bvec, unsigned long *flags)
526{
527 return page_address(bvec->bv_page) + bvec->bv_offset;
528}
529
530static inline void bvec_kunmap_irq(char *buffer, unsigned long *flags)
531{
532 *flags = 0;
533}
1da177e4
LT
534#endif
535
f619d254 536static inline char *__bio_kmap_irq(struct bio *bio, struct bvec_iter iter,
1da177e4
LT
537 unsigned long *flags)
538{
f619d254 539 return bvec_kmap_irq(&bio_iter_iovec(bio, iter), flags);
1da177e4
LT
540}
541#define __bio_kunmap_irq(buf, flags) bvec_kunmap_irq(buf, flags)
542
543#define bio_kmap_irq(bio, flags) \
f619d254 544 __bio_kmap_irq((bio), (bio)->bi_iter, (flags))
1da177e4
LT
545#define bio_kunmap_irq(buf,flags) __bio_kunmap_irq(buf, flags)
546
8f3d8ba2 547/*
e686307f 548 * BIO list management for use by remapping drivers (e.g. DM or MD) and loop.
8f3d8ba2
CH
549 *
550 * A bio_list anchors a singly-linked list of bios chained through the bi_next
551 * member of the bio. The bio_list also caches the last list member to allow
552 * fast access to the tail.
553 */
554struct bio_list {
555 struct bio *head;
556 struct bio *tail;
557};
558
559static inline int bio_list_empty(const struct bio_list *bl)
560{
561 return bl->head == NULL;
562}
563
564static inline void bio_list_init(struct bio_list *bl)
565{
566 bl->head = bl->tail = NULL;
567}
568
320ae51f
JA
569#define BIO_EMPTY_LIST { NULL, NULL }
570
8f3d8ba2
CH
571#define bio_list_for_each(bio, bl) \
572 for (bio = (bl)->head; bio; bio = bio->bi_next)
573
574static inline unsigned bio_list_size(const struct bio_list *bl)
575{
576 unsigned sz = 0;
577 struct bio *bio;
578
579 bio_list_for_each(bio, bl)
580 sz++;
581
582 return sz;
583}
584
585static inline void bio_list_add(struct bio_list *bl, struct bio *bio)
586{
587 bio->bi_next = NULL;
588
589 if (bl->tail)
590 bl->tail->bi_next = bio;
591 else
592 bl->head = bio;
593
594 bl->tail = bio;
595}
596
597static inline void bio_list_add_head(struct bio_list *bl, struct bio *bio)
598{
599 bio->bi_next = bl->head;
600
601 bl->head = bio;
602
603 if (!bl->tail)
604 bl->tail = bio;
605}
606
607static inline void bio_list_merge(struct bio_list *bl, struct bio_list *bl2)
608{
609 if (!bl2->head)
610 return;
611
612 if (bl->tail)
613 bl->tail->bi_next = bl2->head;
614 else
615 bl->head = bl2->head;
616
617 bl->tail = bl2->tail;
618}
619
620static inline void bio_list_merge_head(struct bio_list *bl,
621 struct bio_list *bl2)
622{
623 if (!bl2->head)
624 return;
625
626 if (bl->head)
627 bl2->tail->bi_next = bl->head;
628 else
629 bl->tail = bl2->tail;
630
631 bl->head = bl2->head;
632}
633
13685a16
GU
634static inline struct bio *bio_list_peek(struct bio_list *bl)
635{
636 return bl->head;
637}
638
8f3d8ba2
CH
639static inline struct bio *bio_list_pop(struct bio_list *bl)
640{
641 struct bio *bio = bl->head;
642
643 if (bio) {
644 bl->head = bl->head->bi_next;
645 if (!bl->head)
646 bl->tail = NULL;
647
648 bio->bi_next = NULL;
649 }
650
651 return bio;
652}
653
654static inline struct bio *bio_list_get(struct bio_list *bl)
655{
656 struct bio *bio = bl->head;
657
658 bl->head = bl->tail = NULL;
659
660 return bio;
661}
662
57fb233f
KO
663/*
664 * bio_set is used to allow other portions of the IO system to
665 * allocate their own private memory pools for bio and iovec structures.
666 * These memory pools in turn all allocate from the bio_slab
667 * and the bvec_slabs[].
668 */
669#define BIO_POOL_SIZE 2
670#define BIOVEC_NR_POOLS 6
671#define BIOVEC_MAX_IDX (BIOVEC_NR_POOLS - 1)
672
673struct bio_set {
674 struct kmem_cache *bio_slab;
675 unsigned int front_pad;
676
677 mempool_t *bio_pool;
9f060e22 678 mempool_t *bvec_pool;
57fb233f
KO
679#if defined(CONFIG_BLK_DEV_INTEGRITY)
680 mempool_t *bio_integrity_pool;
9f060e22 681 mempool_t *bvec_integrity_pool;
57fb233f 682#endif
df2cb6da
KO
683
684 /*
685 * Deadlock avoidance for stacking block drivers: see comments in
686 * bio_alloc_bioset() for details
687 */
688 spinlock_t rescue_lock;
689 struct bio_list rescue_list;
690 struct work_struct rescue_work;
691 struct workqueue_struct *rescue_workqueue;
57fb233f
KO
692};
693
694struct biovec_slab {
695 int nr_vecs;
696 char *name;
697 struct kmem_cache *slab;
698};
699
700/*
701 * a small number of entries is fine, not going to be performance critical.
702 * basically we just need to survive
703 */
704#define BIO_SPLIT_ENTRIES 2
705
7ba1ba12
MP
706#if defined(CONFIG_BLK_DEV_INTEGRITY)
707
d57a5f7c
KO
708#define bip_for_each_vec(bvl, bip, iter) \
709 for_each_bvec(bvl, (bip)->bip_vec, iter, (bip)->bip_iter)
7ba1ba12 710
13f05c8d
MP
711#define bio_for_each_integrity_vec(_bvl, _bio, _iter) \
712 for_each_bio(_bio) \
713 bip_for_each_vec(_bvl, _bio->bi_integrity, _iter)
714
7ba1ba12 715extern struct bio_integrity_payload *bio_integrity_alloc(struct bio *, gfp_t, unsigned int);
1e2a410f 716extern void bio_integrity_free(struct bio *);
7ba1ba12 717extern int bio_integrity_add_page(struct bio *, struct page *, unsigned int, unsigned int);
e7258c1a 718extern bool bio_integrity_enabled(struct bio *bio);
7ba1ba12
MP
719extern int bio_integrity_prep(struct bio *);
720extern void bio_integrity_endio(struct bio *, int);
721extern void bio_integrity_advance(struct bio *, unsigned int);
722extern void bio_integrity_trim(struct bio *, unsigned int, unsigned int);
1e2a410f 723extern int bio_integrity_clone(struct bio *, struct bio *, gfp_t);
7878cba9
MP
724extern int bioset_integrity_create(struct bio_set *, int);
725extern void bioset_integrity_free(struct bio_set *);
726extern void bio_integrity_init(void);
7ba1ba12
MP
727
728#else /* CONFIG_BLK_DEV_INTEGRITY */
729
c611529e 730static inline void *bio_integrity(struct bio *bio)
6898e3bd 731{
c611529e 732 return NULL;
6898e3bd
MP
733}
734
e7258c1a 735static inline bool bio_integrity_enabled(struct bio *bio)
6898e3bd 736{
e7258c1a 737 return false;
6898e3bd
MP
738}
739
740static inline int bioset_integrity_create(struct bio_set *bs, int pool_size)
741{
742 return 0;
743}
744
745static inline void bioset_integrity_free (struct bio_set *bs)
746{
747 return;
748}
749
750static inline int bio_integrity_prep(struct bio *bio)
751{
752 return 0;
753}
754
1e2a410f 755static inline void bio_integrity_free(struct bio *bio)
6898e3bd
MP
756{
757 return;
758}
759
0c614e2d 760static inline int bio_integrity_clone(struct bio *bio, struct bio *bio_src,
1e2a410f 761 gfp_t gfp_mask)
0c614e2d
SR
762{
763 return 0;
764}
6898e3bd 765
6898e3bd
MP
766static inline void bio_integrity_advance(struct bio *bio,
767 unsigned int bytes_done)
768{
769 return;
770}
771
772static inline void bio_integrity_trim(struct bio *bio, unsigned int offset,
773 unsigned int sectors)
774{
775 return;
776}
777
778static inline void bio_integrity_init(void)
779{
780 return;
781}
7ba1ba12 782
c611529e
MP
783static inline bool bio_integrity_flagged(struct bio *bio, enum bip_flags flag)
784{
785 return false;
786}
787
7ba1ba12
MP
788#endif /* CONFIG_BLK_DEV_INTEGRITY */
789
02a5e0ac 790#endif /* CONFIG_BLOCK */
1da177e4 791#endif /* __LINUX_BIO_H */