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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
f4595875 186static inline unsigned bio_segments(struct bio *bio)
458b76ed
KO
187{
188 unsigned segs = 0;
189 struct bio_vec bv;
190 struct bvec_iter iter;
191
8423ae3d 192 /*
a6f0788e
CK
193 * We special case discard/write same/write zeroes, because they
194 * interpret bi_size differently:
8423ae3d
KO
195 */
196
a6f0788e
CK
197 switch (bio_op(bio)) {
198 case REQ_OP_DISCARD:
199 case REQ_OP_SECURE_ERASE:
a6f0788e 200 case REQ_OP_WRITE_ZEROES:
f9d03f96
CH
201 return 0;
202 case REQ_OP_WRITE_SAME:
8423ae3d 203 return 1;
a6f0788e
CK
204 default:
205 break;
206 }
8423ae3d 207
f4595875 208 bio_for_each_segment(bv, bio, iter)
458b76ed
KO
209 segs++;
210
211 return segs;
212}
213
1da177e4
LT
214/*
215 * get a reference to a bio, so it won't disappear. the intended use is
216 * something like:
217 *
218 * bio_get(bio);
219 * submit_bio(rw, bio);
220 * if (bio->bi_flags ...)
221 * do_something
222 * bio_put(bio);
223 *
224 * without the bio_get(), it could potentially complete I/O before submit_bio
225 * returns. and then bio would be freed memory when if (bio->bi_flags ...)
226 * runs
227 */
dac56212
JA
228static inline void bio_get(struct bio *bio)
229{
230 bio->bi_flags |= (1 << BIO_REFFED);
231 smp_mb__before_atomic();
232 atomic_inc(&bio->__bi_cnt);
233}
234
235static inline void bio_cnt_set(struct bio *bio, unsigned int count)
236{
237 if (count != 1) {
238 bio->bi_flags |= (1 << BIO_REFFED);
239 smp_mb__before_atomic();
240 }
241 atomic_set(&bio->__bi_cnt, count);
242}
1da177e4 243
b7c44ed9
JA
244static inline bool bio_flagged(struct bio *bio, unsigned int bit)
245{
2c68f6dc 246 return (bio->bi_flags & (1U << bit)) != 0;
b7c44ed9
JA
247}
248
249static inline void bio_set_flag(struct bio *bio, unsigned int bit)
250{
2c68f6dc 251 bio->bi_flags |= (1U << bit);
b7c44ed9
JA
252}
253
254static inline void bio_clear_flag(struct bio *bio, unsigned int bit)
255{
2c68f6dc 256 bio->bi_flags &= ~(1U << bit);
b7c44ed9
JA
257}
258
7bcd79ac
ML
259static inline void bio_get_first_bvec(struct bio *bio, struct bio_vec *bv)
260{
261 *bv = bio_iovec(bio);
262}
263
264static inline void bio_get_last_bvec(struct bio *bio, struct bio_vec *bv)
265{
266 struct bvec_iter iter = bio->bi_iter;
267 int idx;
268
7bcd79ac
ML
269 if (unlikely(!bio_multiple_segments(bio))) {
270 *bv = bio_iovec(bio);
271 return;
272 }
273
274 bio_advance_iter(bio, &iter, iter.bi_size);
275
276 if (!iter.bi_bvec_done)
277 idx = iter.bi_idx - 1;
278 else /* in the middle of bvec */
279 idx = iter.bi_idx;
280
281 *bv = bio->bi_io_vec[idx];
282
283 /*
284 * iter.bi_bvec_done records actual length of the last bvec
285 * if this bio ends in the middle of one io vector
286 */
287 if (iter.bi_bvec_done)
288 bv->bv_len = iter.bi_bvec_done;
289}
290
c611529e
MP
291enum bip_flags {
292 BIP_BLOCK_INTEGRITY = 1 << 0, /* block layer owns integrity data */
293 BIP_MAPPED_INTEGRITY = 1 << 1, /* ref tag has been remapped */
294 BIP_CTRL_NOCHECK = 1 << 2, /* disable HBA integrity checking */
295 BIP_DISK_NOCHECK = 1 << 3, /* disable disk integrity checking */
296 BIP_IP_CHECKSUM = 1 << 4, /* IP checksum */
297};
298
7ba1ba12
MP
299/*
300 * bio integrity payload
301 */
302struct bio_integrity_payload {
303 struct bio *bip_bio; /* parent bio */
7ba1ba12 304
d57a5f7c 305 struct bvec_iter bip_iter;
7ba1ba12 306
d57a5f7c 307 bio_end_io_t *bip_end_io; /* saved I/O completion fn */
7ba1ba12 308
7878cba9 309 unsigned short bip_slab; /* slab the bip came from */
7ba1ba12 310 unsigned short bip_vcnt; /* # of integrity bio_vecs */
cbcd1054 311 unsigned short bip_max_vcnt; /* integrity bio_vec slots */
b1f01388 312 unsigned short bip_flags; /* control flags */
7ba1ba12
MP
313
314 struct work_struct bip_work; /* I/O completion */
6fda981c
KO
315
316 struct bio_vec *bip_vec;
317 struct bio_vec bip_inline_vecs[0];/* embedded bvec array */
7ba1ba12 318};
18593088 319
06c1e390
KB
320#if defined(CONFIG_BLK_DEV_INTEGRITY)
321
322static inline struct bio_integrity_payload *bio_integrity(struct bio *bio)
323{
1eff9d32 324 if (bio->bi_opf & REQ_INTEGRITY)
06c1e390
KB
325 return bio->bi_integrity;
326
327 return NULL;
328}
329
c611529e
MP
330static inline bool bio_integrity_flagged(struct bio *bio, enum bip_flags flag)
331{
332 struct bio_integrity_payload *bip = bio_integrity(bio);
333
334 if (bip)
335 return bip->bip_flags & flag;
336
337 return false;
338}
b1f01388 339
18593088
MP
340static inline sector_t bip_get_seed(struct bio_integrity_payload *bip)
341{
342 return bip->bip_iter.bi_sector;
343}
344
345static inline void bip_set_seed(struct bio_integrity_payload *bip,
346 sector_t seed)
347{
348 bip->bip_iter.bi_sector = seed;
349}
350
7ba1ba12 351#endif /* CONFIG_BLK_DEV_INTEGRITY */
1da177e4 352
6678d83f 353extern void bio_trim(struct bio *bio, int offset, int size);
20d0189b
KO
354extern struct bio *bio_split(struct bio *bio, int sectors,
355 gfp_t gfp, struct bio_set *bs);
356
357/**
358 * bio_next_split - get next @sectors from a bio, splitting if necessary
359 * @bio: bio to split
360 * @sectors: number of sectors to split from the front of @bio
361 * @gfp: gfp mask
362 * @bs: bio set to allocate from
363 *
364 * Returns a bio representing the next @sectors of @bio - if the bio is smaller
365 * than @sectors, returns the original bio unchanged.
366 */
367static inline struct bio *bio_next_split(struct bio *bio, int sectors,
368 gfp_t gfp, struct bio_set *bs)
369{
370 if (sectors >= bio_sectors(bio))
371 return bio;
372
373 return bio_split(bio, sectors, gfp, bs);
374}
375
bb799ca0 376extern struct bio_set *bioset_create(unsigned int, unsigned int);
d8f429e1 377extern struct bio_set *bioset_create_nobvec(unsigned int, unsigned int);
1da177e4 378extern void bioset_free(struct bio_set *);
a6c39cb4 379extern mempool_t *biovec_create_pool(int pool_entries);
1da177e4 380
7a88fa19 381extern struct bio *bio_alloc_bioset(gfp_t, unsigned int, struct bio_set *);
1da177e4
LT
382extern void bio_put(struct bio *);
383
59d276fe
KO
384extern void __bio_clone_fast(struct bio *, struct bio *);
385extern struct bio *bio_clone_fast(struct bio *, gfp_t, struct bio_set *);
bf800ef1
KO
386extern struct bio *bio_clone_bioset(struct bio *, gfp_t, struct bio_set *bs);
387
3f86a82a
KO
388extern struct bio_set *fs_bio_set;
389
390static inline struct bio *bio_alloc(gfp_t gfp_mask, unsigned int nr_iovecs)
391{
392 return bio_alloc_bioset(gfp_mask, nr_iovecs, fs_bio_set);
393}
394
bf800ef1
KO
395static inline struct bio *bio_clone(struct bio *bio, gfp_t gfp_mask)
396{
397 return bio_clone_bioset(bio, gfp_mask, fs_bio_set);
398}
399
3f86a82a
KO
400static inline struct bio *bio_kmalloc(gfp_t gfp_mask, unsigned int nr_iovecs)
401{
402 return bio_alloc_bioset(gfp_mask, nr_iovecs, NULL);
403}
404
bf800ef1
KO
405static inline struct bio *bio_clone_kmalloc(struct bio *bio, gfp_t gfp_mask)
406{
407 return bio_clone_bioset(bio, gfp_mask, NULL);
408
409}
410
1e3914d4
CH
411extern blk_qc_t submit_bio(struct bio *);
412
4246a0b6
CH
413extern void bio_endio(struct bio *);
414
415static inline void bio_io_error(struct bio *bio)
416{
417 bio->bi_error = -EIO;
418 bio_endio(bio);
419}
420
1da177e4
LT
421struct request_queue;
422extern int bio_phys_segments(struct request_queue *, struct bio *);
1da177e4 423
4e49ea4a 424extern int submit_bio_wait(struct bio *bio);
054bdf64
KO
425extern void bio_advance(struct bio *, unsigned);
426
3a83f467
ML
427extern void bio_init(struct bio *bio, struct bio_vec *table,
428 unsigned short max_vecs);
9ae3b3f5 429extern void bio_uninit(struct bio *);
f44b48c7 430extern void bio_reset(struct bio *);
196d38bc 431void bio_chain(struct bio *, struct bio *);
1da177e4
LT
432
433extern int bio_add_page(struct bio *, struct page *, unsigned int,unsigned int);
6e68af66
MC
434extern int bio_add_pc_page(struct request_queue *, struct bio *, struct page *,
435 unsigned int, unsigned int);
2cefe4db 436int bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter);
152e283f 437struct rq_map_data;
f1970baf 438extern struct bio *bio_map_user_iov(struct request_queue *,
26e49cfc 439 const struct iov_iter *, gfp_t);
1da177e4 440extern void bio_unmap_user(struct bio *);
df46b9a4 441extern struct bio *bio_map_kern(struct request_queue *, void *, unsigned int,
27496a8c 442 gfp_t);
68154e90
FT
443extern struct bio *bio_copy_kern(struct request_queue *, void *, unsigned int,
444 gfp_t, int);
1da177e4
LT
445extern void bio_set_pages_dirty(struct bio *bio);
446extern void bio_check_pages_dirty(struct bio *bio);
2d4dc890 447
394ffa50
GZ
448void generic_start_io_acct(int rw, unsigned long sectors,
449 struct hd_struct *part);
450void generic_end_io_acct(int rw, struct hd_struct *part,
451 unsigned long start_time);
452
2d4dc890
IL
453#ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
454# error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform"
455#endif
456#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
457extern void bio_flush_dcache_pages(struct bio *bi);
458#else
459static inline void bio_flush_dcache_pages(struct bio *bi)
460{
461}
462#endif
463
16ac3d63 464extern void bio_copy_data(struct bio *dst, struct bio *src);
a0787606 465extern int bio_alloc_pages(struct bio *bio, gfp_t gfp);
491221f8 466extern void bio_free_pages(struct bio *bio);
16ac3d63 467
152e283f 468extern struct bio *bio_copy_user_iov(struct request_queue *,
86d564c8 469 struct rq_map_data *,
26e49cfc
KO
470 const struct iov_iter *,
471 gfp_t);
1da177e4
LT
472extern int bio_uncopy_user(struct bio *);
473void zero_fill_bio(struct bio *bio);
9f060e22
KO
474extern struct bio_vec *bvec_alloc(gfp_t, int, unsigned long *, mempool_t *);
475extern void bvec_free(mempool_t *, struct bio_vec *, unsigned int);
7ba1ba12 476extern unsigned int bvec_nr_vecs(unsigned short idx);
51d654e1 477
852c788f 478#ifdef CONFIG_BLK_CGROUP
1d933cf0 479int bio_associate_blkcg(struct bio *bio, struct cgroup_subsys_state *blkcg_css);
852c788f
TH
480int bio_associate_current(struct bio *bio);
481void bio_disassociate_task(struct bio *bio);
20bd723e 482void bio_clone_blkcg_association(struct bio *dst, struct bio *src);
852c788f 483#else /* CONFIG_BLK_CGROUP */
1d933cf0
TH
484static inline int bio_associate_blkcg(struct bio *bio,
485 struct cgroup_subsys_state *blkcg_css) { return 0; }
852c788f
TH
486static inline int bio_associate_current(struct bio *bio) { return -ENOENT; }
487static inline void bio_disassociate_task(struct bio *bio) { }
20bd723e
PV
488static inline void bio_clone_blkcg_association(struct bio *dst,
489 struct bio *src) { }
852c788f
TH
490#endif /* CONFIG_BLK_CGROUP */
491
1da177e4
LT
492#ifdef CONFIG_HIGHMEM
493/*
20b636bf
AB
494 * remember never ever reenable interrupts between a bvec_kmap_irq and
495 * bvec_kunmap_irq!
1da177e4 496 */
4f570f99 497static inline char *bvec_kmap_irq(struct bio_vec *bvec, unsigned long *flags)
1da177e4
LT
498{
499 unsigned long addr;
500
501 /*
502 * might not be a highmem page, but the preempt/irq count
503 * balancing is a lot nicer this way
504 */
505 local_irq_save(*flags);
e8e3c3d6 506 addr = (unsigned long) kmap_atomic(bvec->bv_page);
1da177e4
LT
507
508 BUG_ON(addr & ~PAGE_MASK);
509
510 return (char *) addr + bvec->bv_offset;
511}
512
4f570f99 513static inline void bvec_kunmap_irq(char *buffer, unsigned long *flags)
1da177e4
LT
514{
515 unsigned long ptr = (unsigned long) buffer & PAGE_MASK;
516
e8e3c3d6 517 kunmap_atomic((void *) ptr);
1da177e4
LT
518 local_irq_restore(*flags);
519}
520
521#else
11a691be
GU
522static inline char *bvec_kmap_irq(struct bio_vec *bvec, unsigned long *flags)
523{
524 return page_address(bvec->bv_page) + bvec->bv_offset;
525}
526
527static inline void bvec_kunmap_irq(char *buffer, unsigned long *flags)
528{
529 *flags = 0;
530}
1da177e4
LT
531#endif
532
f619d254 533static inline char *__bio_kmap_irq(struct bio *bio, struct bvec_iter iter,
1da177e4
LT
534 unsigned long *flags)
535{
f619d254 536 return bvec_kmap_irq(&bio_iter_iovec(bio, iter), flags);
1da177e4
LT
537}
538#define __bio_kunmap_irq(buf, flags) bvec_kunmap_irq(buf, flags)
539
540#define bio_kmap_irq(bio, flags) \
f619d254 541 __bio_kmap_irq((bio), (bio)->bi_iter, (flags))
1da177e4
LT
542#define bio_kunmap_irq(buf,flags) __bio_kunmap_irq(buf, flags)
543
8f3d8ba2 544/*
e686307f 545 * BIO list management for use by remapping drivers (e.g. DM or MD) and loop.
8f3d8ba2
CH
546 *
547 * A bio_list anchors a singly-linked list of bios chained through the bi_next
548 * member of the bio. The bio_list also caches the last list member to allow
549 * fast access to the tail.
550 */
551struct bio_list {
552 struct bio *head;
553 struct bio *tail;
554};
555
556static inline int bio_list_empty(const struct bio_list *bl)
557{
558 return bl->head == NULL;
559}
560
561static inline void bio_list_init(struct bio_list *bl)
562{
563 bl->head = bl->tail = NULL;
564}
565
320ae51f
JA
566#define BIO_EMPTY_LIST { NULL, NULL }
567
8f3d8ba2
CH
568#define bio_list_for_each(bio, bl) \
569 for (bio = (bl)->head; bio; bio = bio->bi_next)
570
571static inline unsigned bio_list_size(const struct bio_list *bl)
572{
573 unsigned sz = 0;
574 struct bio *bio;
575
576 bio_list_for_each(bio, bl)
577 sz++;
578
579 return sz;
580}
581
582static inline void bio_list_add(struct bio_list *bl, struct bio *bio)
583{
584 bio->bi_next = NULL;
585
586 if (bl->tail)
587 bl->tail->bi_next = bio;
588 else
589 bl->head = bio;
590
591 bl->tail = bio;
592}
593
594static inline void bio_list_add_head(struct bio_list *bl, struct bio *bio)
595{
596 bio->bi_next = bl->head;
597
598 bl->head = bio;
599
600 if (!bl->tail)
601 bl->tail = bio;
602}
603
604static inline void bio_list_merge(struct bio_list *bl, struct bio_list *bl2)
605{
606 if (!bl2->head)
607 return;
608
609 if (bl->tail)
610 bl->tail->bi_next = bl2->head;
611 else
612 bl->head = bl2->head;
613
614 bl->tail = bl2->tail;
615}
616
617static inline void bio_list_merge_head(struct bio_list *bl,
618 struct bio_list *bl2)
619{
620 if (!bl2->head)
621 return;
622
623 if (bl->head)
624 bl2->tail->bi_next = bl->head;
625 else
626 bl->tail = bl2->tail;
627
628 bl->head = bl2->head;
629}
630
13685a16
GU
631static inline struct bio *bio_list_peek(struct bio_list *bl)
632{
633 return bl->head;
634}
635
8f3d8ba2
CH
636static inline struct bio *bio_list_pop(struct bio_list *bl)
637{
638 struct bio *bio = bl->head;
639
640 if (bio) {
641 bl->head = bl->head->bi_next;
642 if (!bl->head)
643 bl->tail = NULL;
644
645 bio->bi_next = NULL;
646 }
647
648 return bio;
649}
650
651static inline struct bio *bio_list_get(struct bio_list *bl)
652{
653 struct bio *bio = bl->head;
654
655 bl->head = bl->tail = NULL;
656
657 return bio;
658}
659
0ef5a50c
MS
660/*
661 * Increment chain count for the bio. Make sure the CHAIN flag update
662 * is visible before the raised count.
663 */
664static inline void bio_inc_remaining(struct bio *bio)
665{
666 bio_set_flag(bio, BIO_CHAIN);
667 smp_mb__before_atomic();
668 atomic_inc(&bio->__bi_remaining);
669}
670
57fb233f
KO
671/*
672 * bio_set is used to allow other portions of the IO system to
673 * allocate their own private memory pools for bio and iovec structures.
674 * These memory pools in turn all allocate from the bio_slab
675 * and the bvec_slabs[].
676 */
677#define BIO_POOL_SIZE 2
57fb233f
KO
678
679struct bio_set {
680 struct kmem_cache *bio_slab;
681 unsigned int front_pad;
682
683 mempool_t *bio_pool;
9f060e22 684 mempool_t *bvec_pool;
57fb233f
KO
685#if defined(CONFIG_BLK_DEV_INTEGRITY)
686 mempool_t *bio_integrity_pool;
9f060e22 687 mempool_t *bvec_integrity_pool;
57fb233f 688#endif
df2cb6da
KO
689
690 /*
691 * Deadlock avoidance for stacking block drivers: see comments in
692 * bio_alloc_bioset() for details
693 */
694 spinlock_t rescue_lock;
695 struct bio_list rescue_list;
696 struct work_struct rescue_work;
697 struct workqueue_struct *rescue_workqueue;
57fb233f
KO
698};
699
700struct biovec_slab {
701 int nr_vecs;
702 char *name;
703 struct kmem_cache *slab;
704};
705
706/*
707 * a small number of entries is fine, not going to be performance critical.
708 * basically we just need to survive
709 */
710#define BIO_SPLIT_ENTRIES 2
711
7ba1ba12
MP
712#if defined(CONFIG_BLK_DEV_INTEGRITY)
713
d57a5f7c
KO
714#define bip_for_each_vec(bvl, bip, iter) \
715 for_each_bvec(bvl, (bip)->bip_vec, iter, (bip)->bip_iter)
7ba1ba12 716
13f05c8d
MP
717#define bio_for_each_integrity_vec(_bvl, _bio, _iter) \
718 for_each_bio(_bio) \
719 bip_for_each_vec(_bvl, _bio->bi_integrity, _iter)
720
7ba1ba12 721extern struct bio_integrity_payload *bio_integrity_alloc(struct bio *, gfp_t, unsigned int);
1e2a410f 722extern void bio_integrity_free(struct bio *);
7ba1ba12 723extern int bio_integrity_add_page(struct bio *, struct page *, unsigned int, unsigned int);
e7258c1a 724extern bool bio_integrity_enabled(struct bio *bio);
7ba1ba12 725extern int bio_integrity_prep(struct bio *);
4246a0b6 726extern void bio_integrity_endio(struct bio *);
7ba1ba12
MP
727extern void bio_integrity_advance(struct bio *, unsigned int);
728extern void bio_integrity_trim(struct bio *, unsigned int, unsigned int);
1e2a410f 729extern int bio_integrity_clone(struct bio *, struct bio *, gfp_t);
7878cba9
MP
730extern int bioset_integrity_create(struct bio_set *, int);
731extern void bioset_integrity_free(struct bio_set *);
732extern void bio_integrity_init(void);
7ba1ba12
MP
733
734#else /* CONFIG_BLK_DEV_INTEGRITY */
735
c611529e 736static inline void *bio_integrity(struct bio *bio)
6898e3bd 737{
c611529e 738 return NULL;
6898e3bd
MP
739}
740
e7258c1a 741static inline bool bio_integrity_enabled(struct bio *bio)
6898e3bd 742{
e7258c1a 743 return false;
6898e3bd
MP
744}
745
746static inline int bioset_integrity_create(struct bio_set *bs, int pool_size)
747{
748 return 0;
749}
750
751static inline void bioset_integrity_free (struct bio_set *bs)
752{
753 return;
754}
755
756static inline int bio_integrity_prep(struct bio *bio)
757{
758 return 0;
759}
760
1e2a410f 761static inline void bio_integrity_free(struct bio *bio)
6898e3bd
MP
762{
763 return;
764}
765
0c614e2d 766static inline int bio_integrity_clone(struct bio *bio, struct bio *bio_src,
1e2a410f 767 gfp_t gfp_mask)
0c614e2d
SR
768{
769 return 0;
770}
6898e3bd 771
6898e3bd
MP
772static inline void bio_integrity_advance(struct bio *bio,
773 unsigned int bytes_done)
774{
775 return;
776}
777
778static inline void bio_integrity_trim(struct bio *bio, unsigned int offset,
779 unsigned int sectors)
780{
781 return;
782}
783
784static inline void bio_integrity_init(void)
785{
786 return;
787}
7ba1ba12 788
c611529e
MP
789static inline bool bio_integrity_flagged(struct bio *bio, enum bip_flags flag)
790{
791 return false;
792}
793
06c1e390
KB
794static inline void *bio_integrity_alloc(struct bio * bio, gfp_t gfp,
795 unsigned int nr)
796{
797 return ERR_PTR(-EINVAL);
798}
799
800static inline int bio_integrity_add_page(struct bio *bio, struct page *page,
801 unsigned int len, unsigned int offset)
802{
803 return 0;
804}
805
7ba1ba12
MP
806#endif /* CONFIG_BLK_DEV_INTEGRITY */
807
02a5e0ac 808#endif /* CONFIG_BLOCK */
1da177e4 809#endif /* __LINUX_BIO_H */