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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
458b76ed
KO
186static inline unsigned bio_segments(struct bio *bio)
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:
200 case REQ_OP_WRITE_SAME:
201 case REQ_OP_WRITE_ZEROES:
8423ae3d 202 return 1;
a6f0788e
CK
203 default:
204 break;
205 }
8423ae3d 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{
1eff9d32 323 if (bio->bi_opf & REQ_INTEGRITY)
06c1e390
KB
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
1e3914d4
CH
410extern blk_qc_t submit_bio(struct bio *);
411
4246a0b6
CH
412extern void bio_endio(struct bio *);
413
414static inline void bio_io_error(struct bio *bio)
415{
416 bio->bi_error = -EIO;
417 bio_endio(bio);
418}
419
1da177e4
LT
420struct request_queue;
421extern int bio_phys_segments(struct request_queue *, struct bio *);
1da177e4 422
4e49ea4a 423extern int submit_bio_wait(struct bio *bio);
054bdf64
KO
424extern void bio_advance(struct bio *, unsigned);
425
3a83f467
ML
426extern void bio_init(struct bio *bio, struct bio_vec *table,
427 unsigned short max_vecs);
f44b48c7 428extern void bio_reset(struct bio *);
196d38bc 429void bio_chain(struct bio *, struct bio *);
1da177e4
LT
430
431extern int bio_add_page(struct bio *, struct page *, unsigned int,unsigned int);
6e68af66
MC
432extern int bio_add_pc_page(struct request_queue *, struct bio *, struct page *,
433 unsigned int, unsigned int);
2cefe4db 434int bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter);
152e283f 435struct rq_map_data;
f1970baf 436extern struct bio *bio_map_user_iov(struct request_queue *,
26e49cfc 437 const struct iov_iter *, gfp_t);
1da177e4 438extern void bio_unmap_user(struct bio *);
df46b9a4 439extern struct bio *bio_map_kern(struct request_queue *, void *, unsigned int,
27496a8c 440 gfp_t);
68154e90
FT
441extern struct bio *bio_copy_kern(struct request_queue *, void *, unsigned int,
442 gfp_t, int);
1da177e4
LT
443extern void bio_set_pages_dirty(struct bio *bio);
444extern void bio_check_pages_dirty(struct bio *bio);
2d4dc890 445
394ffa50
GZ
446void generic_start_io_acct(int rw, unsigned long sectors,
447 struct hd_struct *part);
448void generic_end_io_acct(int rw, struct hd_struct *part,
449 unsigned long start_time);
450
2d4dc890
IL
451#ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
452# error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform"
453#endif
454#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
455extern void bio_flush_dcache_pages(struct bio *bi);
456#else
457static inline void bio_flush_dcache_pages(struct bio *bi)
458{
459}
460#endif
461
16ac3d63 462extern void bio_copy_data(struct bio *dst, struct bio *src);
a0787606 463extern int bio_alloc_pages(struct bio *bio, gfp_t gfp);
491221f8 464extern void bio_free_pages(struct bio *bio);
16ac3d63 465
152e283f 466extern struct bio *bio_copy_user_iov(struct request_queue *,
86d564c8 467 struct rq_map_data *,
26e49cfc
KO
468 const struct iov_iter *,
469 gfp_t);
1da177e4
LT
470extern int bio_uncopy_user(struct bio *);
471void zero_fill_bio(struct bio *bio);
9f060e22
KO
472extern struct bio_vec *bvec_alloc(gfp_t, int, unsigned long *, mempool_t *);
473extern void bvec_free(mempool_t *, struct bio_vec *, unsigned int);
7ba1ba12 474extern unsigned int bvec_nr_vecs(unsigned short idx);
51d654e1 475
852c788f 476#ifdef CONFIG_BLK_CGROUP
1d933cf0 477int bio_associate_blkcg(struct bio *bio, struct cgroup_subsys_state *blkcg_css);
852c788f
TH
478int bio_associate_current(struct bio *bio);
479void bio_disassociate_task(struct bio *bio);
20bd723e 480void bio_clone_blkcg_association(struct bio *dst, struct bio *src);
852c788f 481#else /* CONFIG_BLK_CGROUP */
1d933cf0
TH
482static inline int bio_associate_blkcg(struct bio *bio,
483 struct cgroup_subsys_state *blkcg_css) { return 0; }
852c788f
TH
484static inline int bio_associate_current(struct bio *bio) { return -ENOENT; }
485static inline void bio_disassociate_task(struct bio *bio) { }
20bd723e
PV
486static inline void bio_clone_blkcg_association(struct bio *dst,
487 struct bio *src) { }
852c788f
TH
488#endif /* CONFIG_BLK_CGROUP */
489
1da177e4
LT
490#ifdef CONFIG_HIGHMEM
491/*
20b636bf
AB
492 * remember never ever reenable interrupts between a bvec_kmap_irq and
493 * bvec_kunmap_irq!
1da177e4 494 */
4f570f99 495static inline char *bvec_kmap_irq(struct bio_vec *bvec, unsigned long *flags)
1da177e4
LT
496{
497 unsigned long addr;
498
499 /*
500 * might not be a highmem page, but the preempt/irq count
501 * balancing is a lot nicer this way
502 */
503 local_irq_save(*flags);
e8e3c3d6 504 addr = (unsigned long) kmap_atomic(bvec->bv_page);
1da177e4
LT
505
506 BUG_ON(addr & ~PAGE_MASK);
507
508 return (char *) addr + bvec->bv_offset;
509}
510
4f570f99 511static inline void bvec_kunmap_irq(char *buffer, unsigned long *flags)
1da177e4
LT
512{
513 unsigned long ptr = (unsigned long) buffer & PAGE_MASK;
514
e8e3c3d6 515 kunmap_atomic((void *) ptr);
1da177e4
LT
516 local_irq_restore(*flags);
517}
518
519#else
11a691be
GU
520static inline char *bvec_kmap_irq(struct bio_vec *bvec, unsigned long *flags)
521{
522 return page_address(bvec->bv_page) + bvec->bv_offset;
523}
524
525static inline void bvec_kunmap_irq(char *buffer, unsigned long *flags)
526{
527 *flags = 0;
528}
1da177e4
LT
529#endif
530
f619d254 531static inline char *__bio_kmap_irq(struct bio *bio, struct bvec_iter iter,
1da177e4
LT
532 unsigned long *flags)
533{
f619d254 534 return bvec_kmap_irq(&bio_iter_iovec(bio, iter), flags);
1da177e4
LT
535}
536#define __bio_kunmap_irq(buf, flags) bvec_kunmap_irq(buf, flags)
537
538#define bio_kmap_irq(bio, flags) \
f619d254 539 __bio_kmap_irq((bio), (bio)->bi_iter, (flags))
1da177e4
LT
540#define bio_kunmap_irq(buf,flags) __bio_kunmap_irq(buf, flags)
541
8f3d8ba2 542/*
e686307f 543 * BIO list management for use by remapping drivers (e.g. DM or MD) and loop.
8f3d8ba2
CH
544 *
545 * A bio_list anchors a singly-linked list of bios chained through the bi_next
546 * member of the bio. The bio_list also caches the last list member to allow
547 * fast access to the tail.
548 */
549struct bio_list {
550 struct bio *head;
551 struct bio *tail;
552};
553
554static inline int bio_list_empty(const struct bio_list *bl)
555{
556 return bl->head == NULL;
557}
558
559static inline void bio_list_init(struct bio_list *bl)
560{
561 bl->head = bl->tail = NULL;
562}
563
320ae51f
JA
564#define BIO_EMPTY_LIST { NULL, NULL }
565
8f3d8ba2
CH
566#define bio_list_for_each(bio, bl) \
567 for (bio = (bl)->head; bio; bio = bio->bi_next)
568
569static inline unsigned bio_list_size(const struct bio_list *bl)
570{
571 unsigned sz = 0;
572 struct bio *bio;
573
574 bio_list_for_each(bio, bl)
575 sz++;
576
577 return sz;
578}
579
580static inline void bio_list_add(struct bio_list *bl, struct bio *bio)
581{
582 bio->bi_next = NULL;
583
584 if (bl->tail)
585 bl->tail->bi_next = bio;
586 else
587 bl->head = bio;
588
589 bl->tail = bio;
590}
591
592static inline void bio_list_add_head(struct bio_list *bl, struct bio *bio)
593{
594 bio->bi_next = bl->head;
595
596 bl->head = bio;
597
598 if (!bl->tail)
599 bl->tail = bio;
600}
601
602static inline void bio_list_merge(struct bio_list *bl, struct bio_list *bl2)
603{
604 if (!bl2->head)
605 return;
606
607 if (bl->tail)
608 bl->tail->bi_next = bl2->head;
609 else
610 bl->head = bl2->head;
611
612 bl->tail = bl2->tail;
613}
614
615static inline void bio_list_merge_head(struct bio_list *bl,
616 struct bio_list *bl2)
617{
618 if (!bl2->head)
619 return;
620
621 if (bl->head)
622 bl2->tail->bi_next = bl->head;
623 else
624 bl->tail = bl2->tail;
625
626 bl->head = bl2->head;
627}
628
13685a16
GU
629static inline struct bio *bio_list_peek(struct bio_list *bl)
630{
631 return bl->head;
632}
633
8f3d8ba2
CH
634static inline struct bio *bio_list_pop(struct bio_list *bl)
635{
636 struct bio *bio = bl->head;
637
638 if (bio) {
639 bl->head = bl->head->bi_next;
640 if (!bl->head)
641 bl->tail = NULL;
642
643 bio->bi_next = NULL;
644 }
645
646 return bio;
647}
648
649static inline struct bio *bio_list_get(struct bio_list *bl)
650{
651 struct bio *bio = bl->head;
652
653 bl->head = bl->tail = NULL;
654
655 return bio;
656}
657
0ef5a50c
MS
658/*
659 * Increment chain count for the bio. Make sure the CHAIN flag update
660 * is visible before the raised count.
661 */
662static inline void bio_inc_remaining(struct bio *bio)
663{
664 bio_set_flag(bio, BIO_CHAIN);
665 smp_mb__before_atomic();
666 atomic_inc(&bio->__bi_remaining);
667}
668
57fb233f
KO
669/*
670 * bio_set is used to allow other portions of the IO system to
671 * allocate their own private memory pools for bio and iovec structures.
672 * These memory pools in turn all allocate from the bio_slab
673 * and the bvec_slabs[].
674 */
675#define BIO_POOL_SIZE 2
57fb233f
KO
676
677struct bio_set {
678 struct kmem_cache *bio_slab;
679 unsigned int front_pad;
680
681 mempool_t *bio_pool;
9f060e22 682 mempool_t *bvec_pool;
57fb233f
KO
683#if defined(CONFIG_BLK_DEV_INTEGRITY)
684 mempool_t *bio_integrity_pool;
9f060e22 685 mempool_t *bvec_integrity_pool;
57fb233f 686#endif
df2cb6da
KO
687
688 /*
689 * Deadlock avoidance for stacking block drivers: see comments in
690 * bio_alloc_bioset() for details
691 */
692 spinlock_t rescue_lock;
693 struct bio_list rescue_list;
694 struct work_struct rescue_work;
695 struct workqueue_struct *rescue_workqueue;
57fb233f
KO
696};
697
698struct biovec_slab {
699 int nr_vecs;
700 char *name;
701 struct kmem_cache *slab;
702};
703
704/*
705 * a small number of entries is fine, not going to be performance critical.
706 * basically we just need to survive
707 */
708#define BIO_SPLIT_ENTRIES 2
709
7ba1ba12
MP
710#if defined(CONFIG_BLK_DEV_INTEGRITY)
711
d57a5f7c
KO
712#define bip_for_each_vec(bvl, bip, iter) \
713 for_each_bvec(bvl, (bip)->bip_vec, iter, (bip)->bip_iter)
7ba1ba12 714
13f05c8d
MP
715#define bio_for_each_integrity_vec(_bvl, _bio, _iter) \
716 for_each_bio(_bio) \
717 bip_for_each_vec(_bvl, _bio->bi_integrity, _iter)
718
7ba1ba12 719extern struct bio_integrity_payload *bio_integrity_alloc(struct bio *, gfp_t, unsigned int);
1e2a410f 720extern void bio_integrity_free(struct bio *);
7ba1ba12 721extern int bio_integrity_add_page(struct bio *, struct page *, unsigned int, unsigned int);
e7258c1a 722extern bool bio_integrity_enabled(struct bio *bio);
7ba1ba12 723extern int bio_integrity_prep(struct bio *);
4246a0b6 724extern void bio_integrity_endio(struct bio *);
7ba1ba12
MP
725extern void bio_integrity_advance(struct bio *, unsigned int);
726extern void bio_integrity_trim(struct bio *, unsigned int, unsigned int);
1e2a410f 727extern int bio_integrity_clone(struct bio *, struct bio *, gfp_t);
7878cba9
MP
728extern int bioset_integrity_create(struct bio_set *, int);
729extern void bioset_integrity_free(struct bio_set *);
730extern void bio_integrity_init(void);
7ba1ba12
MP
731
732#else /* CONFIG_BLK_DEV_INTEGRITY */
733
c611529e 734static inline void *bio_integrity(struct bio *bio)
6898e3bd 735{
c611529e 736 return NULL;
6898e3bd
MP
737}
738
e7258c1a 739static inline bool bio_integrity_enabled(struct bio *bio)
6898e3bd 740{
e7258c1a 741 return false;
6898e3bd
MP
742}
743
744static inline int bioset_integrity_create(struct bio_set *bs, int pool_size)
745{
746 return 0;
747}
748
749static inline void bioset_integrity_free (struct bio_set *bs)
750{
751 return;
752}
753
754static inline int bio_integrity_prep(struct bio *bio)
755{
756 return 0;
757}
758
1e2a410f 759static inline void bio_integrity_free(struct bio *bio)
6898e3bd
MP
760{
761 return;
762}
763
0c614e2d 764static inline int bio_integrity_clone(struct bio *bio, struct bio *bio_src,
1e2a410f 765 gfp_t gfp_mask)
0c614e2d
SR
766{
767 return 0;
768}
6898e3bd 769
6898e3bd
MP
770static inline void bio_integrity_advance(struct bio *bio,
771 unsigned int bytes_done)
772{
773 return;
774}
775
776static inline void bio_integrity_trim(struct bio *bio, unsigned int offset,
777 unsigned int sectors)
778{
779 return;
780}
781
782static inline void bio_integrity_init(void)
783{
784 return;
785}
7ba1ba12 786
c611529e
MP
787static inline bool bio_integrity_flagged(struct bio *bio, enum bip_flags flag)
788{
789 return false;
790}
791
06c1e390
KB
792static inline void *bio_integrity_alloc(struct bio * bio, gfp_t gfp,
793 unsigned int nr)
794{
795 return ERR_PTR(-EINVAL);
796}
797
798static inline int bio_integrity_add_page(struct bio *bio, struct page *page,
799 unsigned int len, unsigned int offset)
800{
801 return 0;
802}
803
7ba1ba12
MP
804#endif /* CONFIG_BLK_DEV_INTEGRITY */
805
02a5e0ac 806#endif /* CONFIG_BLOCK */
1da177e4 807#endif /* __LINUX_BIO_H */