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block: move two bvec structure into bvec.h
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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
09cbfeaf 44#define BIO_MAX_SIZE (BIO_MAX_PAGES << PAGE_SHIFT)
1da177e4
LT
45#define BIO_MAX_SECTORS (BIO_MAX_SIZE >> 9)
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)
4f024f37
KO
66#define bio_sectors(bio) ((bio)->bi_iter.bi_size >> 9)
67#define bio_end_sector(bio) ((bio)->bi_iter.bi_sector + bio_sectors((bio)))
bf2de6f5 68
458b76ed
KO
69/*
70 * Check whether this bio carries any data or not. A NULL bio is allowed.
71 */
72static inline bool bio_has_data(struct bio *bio)
73{
74 if (bio &&
75 bio->bi_iter.bi_size &&
95fe6c1a 76 bio_op(bio) != REQ_OP_DISCARD)
458b76ed
KO
77 return true;
78
79 return false;
80}
81
95fe6c1a
MC
82static inline bool bio_no_advance_iter(struct bio *bio)
83{
84 return bio_op(bio) == REQ_OP_DISCARD || bio_op(bio) == REQ_OP_WRITE_SAME;
85}
86
458b76ed
KO
87static inline bool bio_is_rw(struct bio *bio)
88{
89 if (!bio_has_data(bio))
90 return false;
91
95fe6c1a 92 if (bio_no_advance_iter(bio))
458b76ed
KO
93 return false;
94
95 return true;
96}
97
98static inline bool bio_mergeable(struct bio *bio)
99{
100 if (bio->bi_rw & REQ_NOMERGE_FLAGS)
101 return false;
102
103 return true;
104}
105
2e46e8b2 106static inline unsigned int bio_cur_bytes(struct bio *bio)
bf2de6f5 107{
458b76ed 108 if (bio_has_data(bio))
a4ad39b1 109 return bio_iovec(bio).bv_len;
fb2dce86 110 else /* dataless requests such as discard */
4f024f37 111 return bio->bi_iter.bi_size;
bf2de6f5
JA
112}
113
114static inline void *bio_data(struct bio *bio)
115{
458b76ed 116 if (bio_has_data(bio))
bf2de6f5
JA
117 return page_address(bio_page(bio)) + bio_offset(bio);
118
119 return NULL;
120}
1da177e4
LT
121
122/*
123 * will die
124 */
125#define bio_to_phys(bio) (page_to_phys(bio_page((bio))) + (unsigned long) bio_offset((bio)))
126#define bvec_to_phys(bv) (page_to_phys((bv)->bv_page) + (unsigned long) (bv)->bv_offset)
127
128/*
129 * queues that have highmem support enabled may still need to revert to
130 * PIO transfers occasionally and thus map high pages temporarily. For
131 * permanent PIO fall back, user is probably better off disabling highmem
132 * I/O completely on that queue (see ide-dma for example)
133 */
f619d254
KO
134#define __bio_kmap_atomic(bio, iter) \
135 (kmap_atomic(bio_iter_iovec((bio), (iter)).bv_page) + \
136 bio_iter_iovec((bio), (iter)).bv_offset)
1da177e4 137
f619d254 138#define __bio_kunmap_atomic(addr) kunmap_atomic(addr)
1da177e4
LT
139
140/*
141 * merge helpers etc
142 */
143
f92131c3
JF
144/* Default implementation of BIOVEC_PHYS_MERGEABLE */
145#define __BIOVEC_PHYS_MERGEABLE(vec1, vec2) \
146 ((bvec_to_phys((vec1)) + (vec1)->bv_len) == bvec_to_phys((vec2)))
147
1da177e4
LT
148/*
149 * allow arch override, for eg virtualized architectures (put in asm/io.h)
150 */
151#ifndef BIOVEC_PHYS_MERGEABLE
152#define BIOVEC_PHYS_MERGEABLE(vec1, vec2) \
f92131c3 153 __BIOVEC_PHYS_MERGEABLE(vec1, vec2)
1da177e4
LT
154#endif
155
1da177e4
LT
156#define __BIO_SEG_BOUNDARY(addr1, addr2, mask) \
157 (((addr1) | (mask)) == (((addr2) - 1) | (mask)))
158#define BIOVEC_SEG_BOUNDARY(q, b1, b2) \
ae03bf63 159 __BIO_SEG_BOUNDARY(bvec_to_phys((b1)), bvec_to_phys((b2)) + (b2)->bv_len, queue_segment_boundary((q)))
1da177e4 160
d74c6d51
KO
161/*
162 * drivers should _never_ use the all version - the bio may have been split
163 * before it got to the driver and the driver won't own all of it
164 */
165#define bio_for_each_segment_all(bvl, bio, i) \
f619d254 166 for (i = 0, bvl = (bio)->bi_io_vec; i < (bio)->bi_vcnt; i++, bvl++)
d74c6d51 167
4550dd6c
KO
168static inline void bio_advance_iter(struct bio *bio, struct bvec_iter *iter,
169 unsigned bytes)
170{
171 iter->bi_sector += bytes >> 9;
172
95fe6c1a 173 if (bio_no_advance_iter(bio))
4550dd6c
KO
174 iter->bi_size -= bytes;
175 else
176 bvec_iter_advance(bio->bi_io_vec, iter, bytes);
177}
178
7988613b
KO
179#define __bio_for_each_segment(bvl, bio, iter, start) \
180 for (iter = (start); \
4550dd6c
KO
181 (iter).bi_size && \
182 ((bvl = bio_iter_iovec((bio), (iter))), 1); \
183 bio_advance_iter((bio), &(iter), (bvl).bv_len))
7988613b
KO
184
185#define bio_for_each_segment(bvl, bio, iter) \
186 __bio_for_each_segment(bvl, bio, iter, (bio)->bi_iter)
187
4550dd6c 188#define bio_iter_last(bvec, iter) ((iter).bi_size == (bvec).bv_len)
1da177e4 189
458b76ed
KO
190static inline unsigned bio_segments(struct bio *bio)
191{
192 unsigned segs = 0;
193 struct bio_vec bv;
194 struct bvec_iter iter;
195
8423ae3d
KO
196 /*
197 * We special case discard/write same, because they interpret bi_size
198 * differently:
199 */
200
95fe6c1a 201 if (bio_op(bio) == REQ_OP_DISCARD)
8423ae3d
KO
202 return 1;
203
95fe6c1a 204 if (bio_op(bio) == REQ_OP_WRITE_SAME)
8423ae3d
KO
205 return 1;
206
458b76ed
KO
207 bio_for_each_segment(bv, bio, iter)
208 segs++;
209
210 return segs;
211}
212
1da177e4
LT
213/*
214 * get a reference to a bio, so it won't disappear. the intended use is
215 * something like:
216 *
217 * bio_get(bio);
218 * submit_bio(rw, bio);
219 * if (bio->bi_flags ...)
220 * do_something
221 * bio_put(bio);
222 *
223 * without the bio_get(), it could potentially complete I/O before submit_bio
224 * returns. and then bio would be freed memory when if (bio->bi_flags ...)
225 * runs
226 */
dac56212
JA
227static inline void bio_get(struct bio *bio)
228{
229 bio->bi_flags |= (1 << BIO_REFFED);
230 smp_mb__before_atomic();
231 atomic_inc(&bio->__bi_cnt);
232}
233
234static inline void bio_cnt_set(struct bio *bio, unsigned int count)
235{
236 if (count != 1) {
237 bio->bi_flags |= (1 << BIO_REFFED);
238 smp_mb__before_atomic();
239 }
240 atomic_set(&bio->__bi_cnt, count);
241}
1da177e4 242
b7c44ed9
JA
243static inline bool bio_flagged(struct bio *bio, unsigned int bit)
244{
2c68f6dc 245 return (bio->bi_flags & (1U << bit)) != 0;
b7c44ed9
JA
246}
247
248static inline void bio_set_flag(struct bio *bio, unsigned int bit)
249{
2c68f6dc 250 bio->bi_flags |= (1U << bit);
b7c44ed9
JA
251}
252
253static inline void bio_clear_flag(struct bio *bio, unsigned int bit)
254{
2c68f6dc 255 bio->bi_flags &= ~(1U << bit);
b7c44ed9
JA
256}
257
7bcd79ac
ML
258static inline void bio_get_first_bvec(struct bio *bio, struct bio_vec *bv)
259{
260 *bv = bio_iovec(bio);
261}
262
263static inline void bio_get_last_bvec(struct bio *bio, struct bio_vec *bv)
264{
265 struct bvec_iter iter = bio->bi_iter;
266 int idx;
267
7bcd79ac
ML
268 if (unlikely(!bio_multiple_segments(bio))) {
269 *bv = bio_iovec(bio);
270 return;
271 }
272
273 bio_advance_iter(bio, &iter, iter.bi_size);
274
275 if (!iter.bi_bvec_done)
276 idx = iter.bi_idx - 1;
277 else /* in the middle of bvec */
278 idx = iter.bi_idx;
279
280 *bv = bio->bi_io_vec[idx];
281
282 /*
283 * iter.bi_bvec_done records actual length of the last bvec
284 * if this bio ends in the middle of one io vector
285 */
286 if (iter.bi_bvec_done)
287 bv->bv_len = iter.bi_bvec_done;
288}
289
c611529e
MP
290enum bip_flags {
291 BIP_BLOCK_INTEGRITY = 1 << 0, /* block layer owns integrity data */
292 BIP_MAPPED_INTEGRITY = 1 << 1, /* ref tag has been remapped */
293 BIP_CTRL_NOCHECK = 1 << 2, /* disable HBA integrity checking */
294 BIP_DISK_NOCHECK = 1 << 3, /* disable disk integrity checking */
295 BIP_IP_CHECKSUM = 1 << 4, /* IP checksum */
296};
297
7ba1ba12
MP
298/*
299 * bio integrity payload
300 */
301struct bio_integrity_payload {
302 struct bio *bip_bio; /* parent bio */
7ba1ba12 303
d57a5f7c 304 struct bvec_iter bip_iter;
7ba1ba12 305
d57a5f7c 306 bio_end_io_t *bip_end_io; /* saved I/O completion fn */
7ba1ba12 307
7878cba9 308 unsigned short bip_slab; /* slab the bip came from */
7ba1ba12 309 unsigned short bip_vcnt; /* # of integrity bio_vecs */
cbcd1054 310 unsigned short bip_max_vcnt; /* integrity bio_vec slots */
b1f01388 311 unsigned short bip_flags; /* control flags */
7ba1ba12
MP
312
313 struct work_struct bip_work; /* I/O completion */
6fda981c
KO
314
315 struct bio_vec *bip_vec;
316 struct bio_vec bip_inline_vecs[0];/* embedded bvec array */
7ba1ba12 317};
18593088 318
06c1e390
KB
319#if defined(CONFIG_BLK_DEV_INTEGRITY)
320
321static inline struct bio_integrity_payload *bio_integrity(struct bio *bio)
322{
323 if (bio->bi_rw & REQ_INTEGRITY)
324 return bio->bi_integrity;
325
326 return NULL;
327}
328
c611529e
MP
329static inline bool bio_integrity_flagged(struct bio *bio, enum bip_flags flag)
330{
331 struct bio_integrity_payload *bip = bio_integrity(bio);
332
333 if (bip)
334 return bip->bip_flags & flag;
335
336 return false;
337}
b1f01388 338
18593088
MP
339static inline sector_t bip_get_seed(struct bio_integrity_payload *bip)
340{
341 return bip->bip_iter.bi_sector;
342}
343
344static inline void bip_set_seed(struct bio_integrity_payload *bip,
345 sector_t seed)
346{
347 bip->bip_iter.bi_sector = seed;
348}
349
7ba1ba12 350#endif /* CONFIG_BLK_DEV_INTEGRITY */
1da177e4 351
6678d83f 352extern void bio_trim(struct bio *bio, int offset, int size);
20d0189b
KO
353extern struct bio *bio_split(struct bio *bio, int sectors,
354 gfp_t gfp, struct bio_set *bs);
355
356/**
357 * bio_next_split - get next @sectors from a bio, splitting if necessary
358 * @bio: bio to split
359 * @sectors: number of sectors to split from the front of @bio
360 * @gfp: gfp mask
361 * @bs: bio set to allocate from
362 *
363 * Returns a bio representing the next @sectors of @bio - if the bio is smaller
364 * than @sectors, returns the original bio unchanged.
365 */
366static inline struct bio *bio_next_split(struct bio *bio, int sectors,
367 gfp_t gfp, struct bio_set *bs)
368{
369 if (sectors >= bio_sectors(bio))
370 return bio;
371
372 return bio_split(bio, sectors, gfp, bs);
373}
374
bb799ca0 375extern struct bio_set *bioset_create(unsigned int, unsigned int);
d8f429e1 376extern struct bio_set *bioset_create_nobvec(unsigned int, unsigned int);
1da177e4 377extern void bioset_free(struct bio_set *);
a6c39cb4 378extern mempool_t *biovec_create_pool(int pool_entries);
1da177e4 379
dd0fc66f 380extern struct bio *bio_alloc_bioset(gfp_t, int, struct bio_set *);
1da177e4
LT
381extern void bio_put(struct bio *);
382
59d276fe
KO
383extern void __bio_clone_fast(struct bio *, struct bio *);
384extern struct bio *bio_clone_fast(struct bio *, gfp_t, struct bio_set *);
bf800ef1
KO
385extern struct bio *bio_clone_bioset(struct bio *, gfp_t, struct bio_set *bs);
386
3f86a82a
KO
387extern struct bio_set *fs_bio_set;
388
389static inline struct bio *bio_alloc(gfp_t gfp_mask, unsigned int nr_iovecs)
390{
391 return bio_alloc_bioset(gfp_mask, nr_iovecs, fs_bio_set);
392}
393
bf800ef1
KO
394static inline struct bio *bio_clone(struct bio *bio, gfp_t gfp_mask)
395{
396 return bio_clone_bioset(bio, gfp_mask, fs_bio_set);
397}
398
3f86a82a
KO
399static inline struct bio *bio_kmalloc(gfp_t gfp_mask, unsigned int nr_iovecs)
400{
401 return bio_alloc_bioset(gfp_mask, nr_iovecs, NULL);
402}
403
bf800ef1
KO
404static inline struct bio *bio_clone_kmalloc(struct bio *bio, gfp_t gfp_mask)
405{
406 return bio_clone_bioset(bio, gfp_mask, NULL);
407
408}
409
4246a0b6
CH
410extern void bio_endio(struct bio *);
411
412static inline void bio_io_error(struct bio *bio)
413{
414 bio->bi_error = -EIO;
415 bio_endio(bio);
416}
417
1da177e4
LT
418struct request_queue;
419extern int bio_phys_segments(struct request_queue *, struct bio *);
1da177e4 420
4e49ea4a 421extern int submit_bio_wait(struct bio *bio);
054bdf64
KO
422extern void bio_advance(struct bio *, unsigned);
423
1da177e4 424extern void bio_init(struct bio *);
f44b48c7 425extern void bio_reset(struct bio *);
196d38bc 426void bio_chain(struct bio *, struct bio *);
1da177e4
LT
427
428extern int bio_add_page(struct bio *, struct page *, unsigned int,unsigned int);
6e68af66
MC
429extern int bio_add_pc_page(struct request_queue *, struct bio *, struct page *,
430 unsigned int, unsigned int);
152e283f 431struct rq_map_data;
f1970baf 432extern struct bio *bio_map_user_iov(struct request_queue *,
26e49cfc 433 const struct iov_iter *, gfp_t);
1da177e4 434extern void bio_unmap_user(struct bio *);
df46b9a4 435extern struct bio *bio_map_kern(struct request_queue *, void *, unsigned int,
27496a8c 436 gfp_t);
68154e90
FT
437extern struct bio *bio_copy_kern(struct request_queue *, void *, unsigned int,
438 gfp_t, int);
1da177e4
LT
439extern void bio_set_pages_dirty(struct bio *bio);
440extern void bio_check_pages_dirty(struct bio *bio);
2d4dc890 441
394ffa50
GZ
442void generic_start_io_acct(int rw, unsigned long sectors,
443 struct hd_struct *part);
444void generic_end_io_acct(int rw, struct hd_struct *part,
445 unsigned long start_time);
446
2d4dc890
IL
447#ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
448# error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform"
449#endif
450#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
451extern void bio_flush_dcache_pages(struct bio *bi);
452#else
453static inline void bio_flush_dcache_pages(struct bio *bi)
454{
455}
456#endif
457
16ac3d63 458extern void bio_copy_data(struct bio *dst, struct bio *src);
a0787606 459extern int bio_alloc_pages(struct bio *bio, gfp_t gfp);
16ac3d63 460
152e283f 461extern struct bio *bio_copy_user_iov(struct request_queue *,
86d564c8 462 struct rq_map_data *,
26e49cfc
KO
463 const struct iov_iter *,
464 gfp_t);
1da177e4
LT
465extern int bio_uncopy_user(struct bio *);
466void zero_fill_bio(struct bio *bio);
9f060e22
KO
467extern struct bio_vec *bvec_alloc(gfp_t, int, unsigned long *, mempool_t *);
468extern void bvec_free(mempool_t *, struct bio_vec *, unsigned int);
7ba1ba12 469extern unsigned int bvec_nr_vecs(unsigned short idx);
51d654e1 470
852c788f 471#ifdef CONFIG_BLK_CGROUP
1d933cf0 472int bio_associate_blkcg(struct bio *bio, struct cgroup_subsys_state *blkcg_css);
852c788f
TH
473int bio_associate_current(struct bio *bio);
474void bio_disassociate_task(struct bio *bio);
475#else /* CONFIG_BLK_CGROUP */
1d933cf0
TH
476static inline int bio_associate_blkcg(struct bio *bio,
477 struct cgroup_subsys_state *blkcg_css) { return 0; }
852c788f
TH
478static inline int bio_associate_current(struct bio *bio) { return -ENOENT; }
479static inline void bio_disassociate_task(struct bio *bio) { }
480#endif /* CONFIG_BLK_CGROUP */
481
1da177e4
LT
482#ifdef CONFIG_HIGHMEM
483/*
20b636bf
AB
484 * remember never ever reenable interrupts between a bvec_kmap_irq and
485 * bvec_kunmap_irq!
1da177e4 486 */
4f570f99 487static inline char *bvec_kmap_irq(struct bio_vec *bvec, unsigned long *flags)
1da177e4
LT
488{
489 unsigned long addr;
490
491 /*
492 * might not be a highmem page, but the preempt/irq count
493 * balancing is a lot nicer this way
494 */
495 local_irq_save(*flags);
e8e3c3d6 496 addr = (unsigned long) kmap_atomic(bvec->bv_page);
1da177e4
LT
497
498 BUG_ON(addr & ~PAGE_MASK);
499
500 return (char *) addr + bvec->bv_offset;
501}
502
4f570f99 503static inline void bvec_kunmap_irq(char *buffer, unsigned long *flags)
1da177e4
LT
504{
505 unsigned long ptr = (unsigned long) buffer & PAGE_MASK;
506
e8e3c3d6 507 kunmap_atomic((void *) ptr);
1da177e4
LT
508 local_irq_restore(*flags);
509}
510
511#else
11a691be
GU
512static inline char *bvec_kmap_irq(struct bio_vec *bvec, unsigned long *flags)
513{
514 return page_address(bvec->bv_page) + bvec->bv_offset;
515}
516
517static inline void bvec_kunmap_irq(char *buffer, unsigned long *flags)
518{
519 *flags = 0;
520}
1da177e4
LT
521#endif
522
f619d254 523static inline char *__bio_kmap_irq(struct bio *bio, struct bvec_iter iter,
1da177e4
LT
524 unsigned long *flags)
525{
f619d254 526 return bvec_kmap_irq(&bio_iter_iovec(bio, iter), flags);
1da177e4
LT
527}
528#define __bio_kunmap_irq(buf, flags) bvec_kunmap_irq(buf, flags)
529
530#define bio_kmap_irq(bio, flags) \
f619d254 531 __bio_kmap_irq((bio), (bio)->bi_iter, (flags))
1da177e4
LT
532#define bio_kunmap_irq(buf,flags) __bio_kunmap_irq(buf, flags)
533
8f3d8ba2 534/*
e686307f 535 * BIO list management for use by remapping drivers (e.g. DM or MD) and loop.
8f3d8ba2
CH
536 *
537 * A bio_list anchors a singly-linked list of bios chained through the bi_next
538 * member of the bio. The bio_list also caches the last list member to allow
539 * fast access to the tail.
540 */
541struct bio_list {
542 struct bio *head;
543 struct bio *tail;
544};
545
546static inline int bio_list_empty(const struct bio_list *bl)
547{
548 return bl->head == NULL;
549}
550
551static inline void bio_list_init(struct bio_list *bl)
552{
553 bl->head = bl->tail = NULL;
554}
555
320ae51f
JA
556#define BIO_EMPTY_LIST { NULL, NULL }
557
8f3d8ba2
CH
558#define bio_list_for_each(bio, bl) \
559 for (bio = (bl)->head; bio; bio = bio->bi_next)
560
561static inline unsigned bio_list_size(const struct bio_list *bl)
562{
563 unsigned sz = 0;
564 struct bio *bio;
565
566 bio_list_for_each(bio, bl)
567 sz++;
568
569 return sz;
570}
571
572static inline void bio_list_add(struct bio_list *bl, struct bio *bio)
573{
574 bio->bi_next = NULL;
575
576 if (bl->tail)
577 bl->tail->bi_next = bio;
578 else
579 bl->head = bio;
580
581 bl->tail = bio;
582}
583
584static inline void bio_list_add_head(struct bio_list *bl, struct bio *bio)
585{
586 bio->bi_next = bl->head;
587
588 bl->head = bio;
589
590 if (!bl->tail)
591 bl->tail = bio;
592}
593
594static inline void bio_list_merge(struct bio_list *bl, struct bio_list *bl2)
595{
596 if (!bl2->head)
597 return;
598
599 if (bl->tail)
600 bl->tail->bi_next = bl2->head;
601 else
602 bl->head = bl2->head;
603
604 bl->tail = bl2->tail;
605}
606
607static inline void bio_list_merge_head(struct bio_list *bl,
608 struct bio_list *bl2)
609{
610 if (!bl2->head)
611 return;
612
613 if (bl->head)
614 bl2->tail->bi_next = bl->head;
615 else
616 bl->tail = bl2->tail;
617
618 bl->head = bl2->head;
619}
620
13685a16
GU
621static inline struct bio *bio_list_peek(struct bio_list *bl)
622{
623 return bl->head;
624}
625
8f3d8ba2
CH
626static inline struct bio *bio_list_pop(struct bio_list *bl)
627{
628 struct bio *bio = bl->head;
629
630 if (bio) {
631 bl->head = bl->head->bi_next;
632 if (!bl->head)
633 bl->tail = NULL;
634
635 bio->bi_next = NULL;
636 }
637
638 return bio;
639}
640
641static inline struct bio *bio_list_get(struct bio_list *bl)
642{
643 struct bio *bio = bl->head;
644
645 bl->head = bl->tail = NULL;
646
647 return bio;
648}
649
0ef5a50c
MS
650/*
651 * Increment chain count for the bio. Make sure the CHAIN flag update
652 * is visible before the raised count.
653 */
654static inline void bio_inc_remaining(struct bio *bio)
655{
656 bio_set_flag(bio, BIO_CHAIN);
657 smp_mb__before_atomic();
658 atomic_inc(&bio->__bi_remaining);
659}
660
57fb233f
KO
661/*
662 * bio_set is used to allow other portions of the IO system to
663 * allocate their own private memory pools for bio and iovec structures.
664 * These memory pools in turn all allocate from the bio_slab
665 * and the bvec_slabs[].
666 */
667#define BIO_POOL_SIZE 2
668#define BIOVEC_NR_POOLS 6
669#define BIOVEC_MAX_IDX (BIOVEC_NR_POOLS - 1)
670
671struct bio_set {
672 struct kmem_cache *bio_slab;
673 unsigned int front_pad;
674
675 mempool_t *bio_pool;
9f060e22 676 mempool_t *bvec_pool;
57fb233f
KO
677#if defined(CONFIG_BLK_DEV_INTEGRITY)
678 mempool_t *bio_integrity_pool;
9f060e22 679 mempool_t *bvec_integrity_pool;
57fb233f 680#endif
df2cb6da
KO
681
682 /*
683 * Deadlock avoidance for stacking block drivers: see comments in
684 * bio_alloc_bioset() for details
685 */
686 spinlock_t rescue_lock;
687 struct bio_list rescue_list;
688 struct work_struct rescue_work;
689 struct workqueue_struct *rescue_workqueue;
57fb233f
KO
690};
691
692struct biovec_slab {
693 int nr_vecs;
694 char *name;
695 struct kmem_cache *slab;
696};
697
698/*
699 * a small number of entries is fine, not going to be performance critical.
700 * basically we just need to survive
701 */
702#define BIO_SPLIT_ENTRIES 2
703
7ba1ba12
MP
704#if defined(CONFIG_BLK_DEV_INTEGRITY)
705
d57a5f7c
KO
706#define bip_for_each_vec(bvl, bip, iter) \
707 for_each_bvec(bvl, (bip)->bip_vec, iter, (bip)->bip_iter)
7ba1ba12 708
13f05c8d
MP
709#define bio_for_each_integrity_vec(_bvl, _bio, _iter) \
710 for_each_bio(_bio) \
711 bip_for_each_vec(_bvl, _bio->bi_integrity, _iter)
712
7ba1ba12 713extern struct bio_integrity_payload *bio_integrity_alloc(struct bio *, gfp_t, unsigned int);
1e2a410f 714extern void bio_integrity_free(struct bio *);
7ba1ba12 715extern int bio_integrity_add_page(struct bio *, struct page *, unsigned int, unsigned int);
e7258c1a 716extern bool bio_integrity_enabled(struct bio *bio);
7ba1ba12 717extern int bio_integrity_prep(struct bio *);
4246a0b6 718extern void bio_integrity_endio(struct bio *);
7ba1ba12
MP
719extern void bio_integrity_advance(struct bio *, unsigned int);
720extern void bio_integrity_trim(struct bio *, unsigned int, unsigned int);
1e2a410f 721extern int bio_integrity_clone(struct bio *, struct bio *, gfp_t);
7878cba9
MP
722extern int bioset_integrity_create(struct bio_set *, int);
723extern void bioset_integrity_free(struct bio_set *);
724extern void bio_integrity_init(void);
7ba1ba12
MP
725
726#else /* CONFIG_BLK_DEV_INTEGRITY */
727
c611529e 728static inline void *bio_integrity(struct bio *bio)
6898e3bd 729{
c611529e 730 return NULL;
6898e3bd
MP
731}
732
e7258c1a 733static inline bool bio_integrity_enabled(struct bio *bio)
6898e3bd 734{
e7258c1a 735 return false;
6898e3bd
MP
736}
737
738static inline int bioset_integrity_create(struct bio_set *bs, int pool_size)
739{
740 return 0;
741}
742
743static inline void bioset_integrity_free (struct bio_set *bs)
744{
745 return;
746}
747
748static inline int bio_integrity_prep(struct bio *bio)
749{
750 return 0;
751}
752
1e2a410f 753static inline void bio_integrity_free(struct bio *bio)
6898e3bd
MP
754{
755 return;
756}
757
0c614e2d 758static inline int bio_integrity_clone(struct bio *bio, struct bio *bio_src,
1e2a410f 759 gfp_t gfp_mask)
0c614e2d
SR
760{
761 return 0;
762}
6898e3bd 763
6898e3bd
MP
764static inline void bio_integrity_advance(struct bio *bio,
765 unsigned int bytes_done)
766{
767 return;
768}
769
770static inline void bio_integrity_trim(struct bio *bio, unsigned int offset,
771 unsigned int sectors)
772{
773 return;
774}
775
776static inline void bio_integrity_init(void)
777{
778 return;
779}
7ba1ba12 780
c611529e
MP
781static inline bool bio_integrity_flagged(struct bio *bio, enum bip_flags flag)
782{
783 return false;
784}
785
06c1e390
KB
786static inline void *bio_integrity_alloc(struct bio * bio, gfp_t gfp,
787 unsigned int nr)
788{
789 return ERR_PTR(-EINVAL);
790}
791
792static inline int bio_integrity_add_page(struct bio *bio, struct page *page,
793 unsigned int len, unsigned int offset)
794{
795 return 0;
796}
797
7ba1ba12
MP
798#endif /* CONFIG_BLK_DEV_INTEGRITY */
799
02a5e0ac 800#endif /* CONFIG_BLOCK */
1da177e4 801#endif /* __LINUX_BIO_H */