]> bbs.cooldavid.org Git - net-next-2.6.git/blame - include/linux/bio.h
cfq-iosched: simplify prio-unboost code
[net-next-2.6.git] / include / linux / bio.h
CommitLineData
1da177e4
LT
1/*
2 * 2.5 block I/O model
3 *
4 * Copyright (C) 2001 Jens Axboe <axboe@suse.de>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12
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>
1da177e4 26
02a5e0ac
DH
27#ifdef CONFIG_BLOCK
28
1da177e4
LT
29#include <asm/io.h>
30
1da177e4
LT
31#define BIO_DEBUG
32
33#ifdef BIO_DEBUG
34#define BIO_BUG_ON BUG_ON
35#else
36#define BIO_BUG_ON
37#endif
38
d84a8477 39#define BIO_MAX_PAGES 256
1da177e4
LT
40#define BIO_MAX_SIZE (BIO_MAX_PAGES << PAGE_CACHE_SHIFT)
41#define BIO_MAX_SECTORS (BIO_MAX_SIZE >> 9)
42
43/*
44 * was unsigned short, but we might as well be ready for > 64kB I/O pages
45 */
46struct bio_vec {
47 struct page *bv_page;
48 unsigned int bv_len;
49 unsigned int bv_offset;
50};
51
52struct bio_set;
53struct bio;
7ba1ba12 54struct bio_integrity_payload;
6712ecf8 55typedef void (bio_end_io_t) (struct bio *, int);
1da177e4
LT
56typedef void (bio_destructor_t) (struct bio *);
57
58/*
59 * main unit of I/O for the block layer and lower layers (ie drivers and
60 * stacking drivers)
61 */
62struct bio {
2c2345c2
RG
63 sector_t bi_sector; /* device address in 512 byte
64 sectors */
1da177e4
LT
65 struct bio *bi_next; /* request queue link */
66 struct block_device *bi_bdev;
67 unsigned long bi_flags; /* status, command, etc */
68 unsigned long bi_rw; /* bottom bits READ/WRITE,
69 * top bits priority
70 */
71
72 unsigned short bi_vcnt; /* how many bio_vec's */
73 unsigned short bi_idx; /* current index into bvl_vec */
74
75 /* Number of segments in this BIO after
76 * physical address coalescing is performed.
77 */
5b99c2ff 78 unsigned int bi_phys_segments;
1da177e4 79
1da177e4
LT
80 unsigned int bi_size; /* residual I/O count */
81
86771427
FT
82 /*
83 * To keep track of the max segment size, we account for the
84 * sizes of the first and last mergeable segments in this bio.
85 */
86 unsigned int bi_seg_front_size;
87 unsigned int bi_seg_back_size;
88
1da177e4
LT
89 unsigned int bi_max_vecs; /* max bvl_vecs we can hold */
90
c7c22e4d
JA
91 unsigned int bi_comp_cpu; /* completion CPU */
92
ba744d5e
RK
93 atomic_t bi_cnt; /* pin count */
94
1da177e4
LT
95 struct bio_vec *bi_io_vec; /* the actual vec list */
96
97 bio_end_io_t *bi_end_io;
1da177e4
LT
98
99 void *bi_private;
7ba1ba12
MP
100#if defined(CONFIG_BLK_DEV_INTEGRITY)
101 struct bio_integrity_payload *bi_integrity; /* data integrity */
102#endif
1da177e4
LT
103
104 bio_destructor_t *bi_destructor; /* destructor */
392ddc32
JA
105
106 /*
107 * We can inline a number of vecs at the end of the bio, to avoid
108 * double allocations for a small number of bio_vecs. This member
109 * MUST obviously be kept at the very end of the bio.
110 */
111 struct bio_vec bi_inline_vecs[0];
1da177e4
LT
112};
113
114/*
115 * bio flags
116 */
117#define BIO_UPTODATE 0 /* ok after I/O completion */
118#define BIO_RW_BLOCK 1 /* RW_AHEAD set, and read/write would block */
119#define BIO_EOF 2 /* out-out-bounds error */
5df97b91 120#define BIO_SEG_VALID 3 /* bi_phys_segments valid */
1da177e4
LT
121#define BIO_CLONED 4 /* doesn't own data */
122#define BIO_BOUNCED 5 /* bio is a bounce bio */
123#define BIO_USER_MAPPED 6 /* contains user pages */
124#define BIO_EOPNOTSUPP 7 /* not supported */
c7c22e4d 125#define BIO_CPU_AFFINE 8 /* complete bio on same CPU as submitted */
81882766 126#define BIO_NULL_MAPPED 9 /* contains invalid user pages */
74aa8c2c 127#define BIO_FS_INTEGRITY 10 /* fs owns integrity data, not block layer */
08bafc03 128#define BIO_QUIET 11 /* Make BIO Quiet */
1da177e4
LT
129#define bio_flagged(bio, flag) ((bio)->bi_flags & (1 << (flag)))
130
131/*
132 * top 4 bits of bio flags indicate the pool this bio came from
133 */
134#define BIO_POOL_BITS (4)
451a9ebf 135#define BIO_POOL_NONE ((1UL << BIO_POOL_BITS) - 1)
1da177e4
LT
136#define BIO_POOL_OFFSET (BITS_PER_LONG - BIO_POOL_BITS)
137#define BIO_POOL_MASK (1UL << BIO_POOL_OFFSET)
138#define BIO_POOL_IDX(bio) ((bio)->bi_flags >> BIO_POOL_OFFSET)
139
140/*
141 * bio bi_rw flags
142 *
af563942
JA
143 * bit 0 -- data direction
144 * If not set, bio is a read from device. If set, it's a write to device.
a82afdfc
TH
145 * bit 1 -- fail fast device errors
146 * bit 2 -- fail fast transport errors
147 * bit 3 -- fail fast driver errors
148 * bit 4 -- rw-ahead when set
149 * bit 5 -- barrier
af563942 150 * Insert a serialization point in the IO queue, forcing previously
16642eb6 151 * submitted IO to be completed before this one is issued.
a82afdfc
TH
152 * bit 6 -- synchronous I/O hint.
153 * bit 7 -- Unplug the device immediately after submitting this bio.
154 * bit 8 -- metadata request
af563942
JA
155 * Used for tracing to differentiate metadata and data IO. May also
156 * get some preferential treatment in the IO scheduler
a82afdfc 157 * bit 9 -- discard sectors
af563942
JA
158 * Informs the lower level device that this range of sectors is no longer
159 * used by the file system and may thus be freed by the device. Used
160 * for flash based storage.
6000a368 161 * Don't want driver retries for any fast fail whatever the reason.
aeb6fafb
JA
162 * bit 10 -- Tell the IO scheduler not to wait for more requests after this
163 one has been submitted, even if it is a SYNC request.
1da177e4 164 */
a82afdfc
TH
165enum bio_rw_flags {
166 BIO_RW,
167 BIO_RW_FAILFAST_DEV,
168 BIO_RW_FAILFAST_TRANSPORT,
169 BIO_RW_FAILFAST_DRIVER,
170 /* above flags must match REQ_* */
171 BIO_RW_AHEAD,
172 BIO_RW_BARRIER,
173 BIO_RW_SYNCIO,
174 BIO_RW_UNPLUG,
175 BIO_RW_META,
176 BIO_RW_DISCARD,
177 BIO_RW_NOIDLE,
178};
213d9417 179
1f98a13f
JA
180/*
181 * First four bits must match between bio->bi_rw and rq->cmd_flags, make
182 * that explicit here.
183 */
184#define BIO_RW_RQ_MASK 0xf
185
e7e503ae
JA
186static inline bool bio_rw_flagged(struct bio *bio, enum bio_rw_flags flag)
187{
188 return (bio->bi_rw & (1 << flag)) != 0;
189}
1dfa17f4 190
22e2c507
JA
191/*
192 * upper 16 bits of bi_rw define the io priority of this bio
193 */
194#define BIO_PRIO_SHIFT (8 * sizeof(unsigned long) - IOPRIO_BITS)
195#define bio_prio(bio) ((bio)->bi_rw >> BIO_PRIO_SHIFT)
196#define bio_prio_valid(bio) ioprio_valid(bio_prio(bio))
197
198#define bio_set_prio(bio, prio) do { \
199 WARN_ON(prio >= (1 << IOPRIO_BITS)); \
200 (bio)->bi_rw &= ((1UL << BIO_PRIO_SHIFT) - 1); \
201 (bio)->bi_rw |= ((unsigned long) (prio) << BIO_PRIO_SHIFT); \
202} while (0)
203
1da177e4
LT
204/*
205 * various member access, note that bio_data should of course not be used
206 * on highmem page vectors
207 */
208#define bio_iovec_idx(bio, idx) (&((bio)->bi_io_vec[(idx)]))
209#define bio_iovec(bio) bio_iovec_idx((bio), (bio)->bi_idx)
210#define bio_page(bio) bio_iovec((bio))->bv_page
211#define bio_offset(bio) bio_iovec((bio))->bv_offset
212#define bio_segments(bio) ((bio)->bi_vcnt - (bio)->bi_idx)
213#define bio_sectors(bio) ((bio)->bi_size >> 9)
1f98a13f 214#define bio_empty_barrier(bio) (bio_rw_flagged(bio, BIO_RW_BARRIER) && !bio_has_data(bio) && !bio_rw_flagged(bio, BIO_RW_DISCARD))
bf2de6f5 215
2e46e8b2 216static inline unsigned int bio_cur_bytes(struct bio *bio)
bf2de6f5
JA
217{
218 if (bio->bi_vcnt)
2e46e8b2 219 return bio_iovec(bio)->bv_len;
fb2dce86 220 else /* dataless requests such as discard */
2e46e8b2 221 return bio->bi_size;
bf2de6f5
JA
222}
223
224static inline void *bio_data(struct bio *bio)
225{
226 if (bio->bi_vcnt)
227 return page_address(bio_page(bio)) + bio_offset(bio);
228
229 return NULL;
230}
1da177e4 231
392ddc32
JA
232static inline int bio_has_allocated_vec(struct bio *bio)
233{
234 return bio->bi_io_vec && bio->bi_io_vec != bio->bi_inline_vecs;
235}
236
1da177e4
LT
237/*
238 * will die
239 */
240#define bio_to_phys(bio) (page_to_phys(bio_page((bio))) + (unsigned long) bio_offset((bio)))
241#define bvec_to_phys(bv) (page_to_phys((bv)->bv_page) + (unsigned long) (bv)->bv_offset)
242
243/*
244 * queues that have highmem support enabled may still need to revert to
245 * PIO transfers occasionally and thus map high pages temporarily. For
246 * permanent PIO fall back, user is probably better off disabling highmem
247 * I/O completely on that queue (see ide-dma for example)
248 */
249#define __bio_kmap_atomic(bio, idx, kmtype) \
250 (kmap_atomic(bio_iovec_idx((bio), (idx))->bv_page, kmtype) + \
251 bio_iovec_idx((bio), (idx))->bv_offset)
252
253#define __bio_kunmap_atomic(addr, kmtype) kunmap_atomic(addr, kmtype)
254
255/*
256 * merge helpers etc
257 */
258
259#define __BVEC_END(bio) bio_iovec_idx((bio), (bio)->bi_vcnt - 1)
260#define __BVEC_START(bio) bio_iovec_idx((bio), (bio)->bi_idx)
261
f92131c3
JF
262/* Default implementation of BIOVEC_PHYS_MERGEABLE */
263#define __BIOVEC_PHYS_MERGEABLE(vec1, vec2) \
264 ((bvec_to_phys((vec1)) + (vec1)->bv_len) == bvec_to_phys((vec2)))
265
1da177e4
LT
266/*
267 * allow arch override, for eg virtualized architectures (put in asm/io.h)
268 */
269#ifndef BIOVEC_PHYS_MERGEABLE
270#define BIOVEC_PHYS_MERGEABLE(vec1, vec2) \
f92131c3 271 __BIOVEC_PHYS_MERGEABLE(vec1, vec2)
1da177e4
LT
272#endif
273
1da177e4
LT
274#define __BIO_SEG_BOUNDARY(addr1, addr2, mask) \
275 (((addr1) | (mask)) == (((addr2) - 1) | (mask)))
276#define BIOVEC_SEG_BOUNDARY(q, b1, b2) \
ae03bf63 277 __BIO_SEG_BOUNDARY(bvec_to_phys((b1)), bvec_to_phys((b2)) + (b2)->bv_len, queue_segment_boundary((q)))
1da177e4
LT
278#define BIO_SEG_BOUNDARY(q, b1, b2) \
279 BIOVEC_SEG_BOUNDARY((q), __BVEC_END((b1)), __BVEC_START((b2)))
280
6712ecf8 281#define bio_io_error(bio) bio_endio((bio), -EIO)
1da177e4
LT
282
283/*
284 * drivers should not use the __ version unless they _really_ want to
285 * run through the entire bio and not just pending pieces
286 */
287#define __bio_for_each_segment(bvl, bio, i, start_idx) \
288 for (bvl = bio_iovec_idx((bio), (start_idx)), i = (start_idx); \
289 i < (bio)->bi_vcnt; \
290 bvl++, i++)
291
292#define bio_for_each_segment(bvl, bio, i) \
293 __bio_for_each_segment(bvl, bio, i, (bio)->bi_idx)
294
295/*
296 * get a reference to a bio, so it won't disappear. the intended use is
297 * something like:
298 *
299 * bio_get(bio);
300 * submit_bio(rw, bio);
301 * if (bio->bi_flags ...)
302 * do_something
303 * bio_put(bio);
304 *
305 * without the bio_get(), it could potentially complete I/O before submit_bio
306 * returns. and then bio would be freed memory when if (bio->bi_flags ...)
307 * runs
308 */
309#define bio_get(bio) atomic_inc(&(bio)->bi_cnt)
310
7ba1ba12
MP
311#if defined(CONFIG_BLK_DEV_INTEGRITY)
312/*
313 * bio integrity payload
314 */
315struct bio_integrity_payload {
316 struct bio *bip_bio; /* parent bio */
7ba1ba12
MP
317
318 sector_t bip_sector; /* virtual start sector */
319
320 void *bip_buf; /* generated integrity data */
321 bio_end_io_t *bip_end_io; /* saved I/O completion fn */
322
7ba1ba12
MP
323 unsigned int bip_size;
324
7878cba9 325 unsigned short bip_slab; /* slab the bip came from */
7ba1ba12
MP
326 unsigned short bip_vcnt; /* # of integrity bio_vecs */
327 unsigned short bip_idx; /* current bip_vec index */
328
329 struct work_struct bip_work; /* I/O completion */
7878cba9 330 struct bio_vec bip_vec[0]; /* embedded bvec array */
7ba1ba12
MP
331};
332#endif /* CONFIG_BLK_DEV_INTEGRITY */
1da177e4
LT
333
334/*
335 * A bio_pair is used when we need to split a bio.
336 * This can only happen for a bio that refers to just one
337 * page of data, and in the unusual situation when the
338 * page crosses a chunk/device boundary
339 *
340 * The address of the master bio is stored in bio1.bi_private
341 * The address of the pool the pair was allocated from is stored
342 * in bio2.bi_private
343 */
344struct bio_pair {
7ba1ba12
MP
345 struct bio bio1, bio2;
346 struct bio_vec bv1, bv2;
347#if defined(CONFIG_BLK_DEV_INTEGRITY)
348 struct bio_integrity_payload bip1, bip2;
349 struct bio_vec iv1, iv2;
350#endif
351 atomic_t cnt;
352 int error;
1da177e4 353};
6feef531 354extern struct bio_pair *bio_split(struct bio *bi, int first_sectors);
1da177e4
LT
355extern void bio_pair_release(struct bio_pair *dbio);
356
bb799ca0 357extern struct bio_set *bioset_create(unsigned int, unsigned int);
1da177e4
LT
358extern void bioset_free(struct bio_set *);
359
dd0fc66f 360extern struct bio *bio_alloc(gfp_t, int);
0a0d96b0 361extern struct bio *bio_kmalloc(gfp_t, int);
dd0fc66f 362extern struct bio *bio_alloc_bioset(gfp_t, int, struct bio_set *);
1da177e4 363extern void bio_put(struct bio *);
3676347a 364extern void bio_free(struct bio *, struct bio_set *);
1da177e4 365
6712ecf8 366extern void bio_endio(struct bio *, int);
1da177e4
LT
367struct request_queue;
368extern int bio_phys_segments(struct request_queue *, struct bio *);
1da177e4
LT
369
370extern void __bio_clone(struct bio *, struct bio *);
dd0fc66f 371extern struct bio *bio_clone(struct bio *, gfp_t);
1da177e4
LT
372
373extern void bio_init(struct bio *);
374
375extern int bio_add_page(struct bio *, struct page *, unsigned int,unsigned int);
6e68af66
MC
376extern int bio_add_pc_page(struct request_queue *, struct bio *, struct page *,
377 unsigned int, unsigned int);
1da177e4 378extern int bio_get_nr_vecs(struct block_device *);
ad3316bf 379extern sector_t bio_sector_offset(struct bio *, unsigned short, unsigned int);
1da177e4 380extern struct bio *bio_map_user(struct request_queue *, struct block_device *,
a3bce90e 381 unsigned long, unsigned int, int, gfp_t);
f1970baf 382struct sg_iovec;
152e283f 383struct rq_map_data;
f1970baf
JB
384extern struct bio *bio_map_user_iov(struct request_queue *,
385 struct block_device *,
a3bce90e 386 struct sg_iovec *, int, int, gfp_t);
1da177e4 387extern void bio_unmap_user(struct bio *);
df46b9a4 388extern struct bio *bio_map_kern(struct request_queue *, void *, unsigned int,
27496a8c 389 gfp_t);
68154e90
FT
390extern struct bio *bio_copy_kern(struct request_queue *, void *, unsigned int,
391 gfp_t, int);
1da177e4
LT
392extern void bio_set_pages_dirty(struct bio *bio);
393extern void bio_check_pages_dirty(struct bio *bio);
152e283f
FT
394extern struct bio *bio_copy_user(struct request_queue *, struct rq_map_data *,
395 unsigned long, unsigned int, int, gfp_t);
396extern struct bio *bio_copy_user_iov(struct request_queue *,
397 struct rq_map_data *, struct sg_iovec *,
a3bce90e 398 int, int, gfp_t);
1da177e4
LT
399extern int bio_uncopy_user(struct bio *);
400void zero_fill_bio(struct bio *bio);
51d654e1 401extern struct bio_vec *bvec_alloc_bs(gfp_t, int, unsigned long *, struct bio_set *);
bb799ca0 402extern void bvec_free_bs(struct bio_set *, struct bio_vec *, unsigned int);
7ba1ba12 403extern unsigned int bvec_nr_vecs(unsigned short idx);
51d654e1 404
c7c22e4d
JA
405/*
406 * Allow queuer to specify a completion CPU for this bio
407 */
408static inline void bio_set_completion_cpu(struct bio *bio, unsigned int cpu)
409{
410 bio->bi_comp_cpu = cpu;
411}
412
51d654e1
MP
413/*
414 * bio_set is used to allow other portions of the IO system to
415 * allocate their own private memory pools for bio and iovec structures.
416 * These memory pools in turn all allocate from the bio_slab
417 * and the bvec_slabs[].
418 */
419#define BIO_POOL_SIZE 2
420#define BIOVEC_NR_POOLS 6
7ff9345f 421#define BIOVEC_MAX_IDX (BIOVEC_NR_POOLS - 1)
51d654e1
MP
422
423struct bio_set {
1b434498 424 struct kmem_cache *bio_slab;
bb799ca0
JA
425 unsigned int front_pad;
426
51d654e1 427 mempool_t *bio_pool;
7878cba9
MP
428#if defined(CONFIG_BLK_DEV_INTEGRITY)
429 mempool_t *bio_integrity_pool;
430#endif
7ff9345f 431 mempool_t *bvec_pool;
51d654e1
MP
432};
433
434struct biovec_slab {
435 int nr_vecs;
436 char *name;
437 struct kmem_cache *slab;
438};
439
440extern struct bio_set *fs_bio_set;
bb799ca0 441extern struct biovec_slab bvec_slabs[BIOVEC_NR_POOLS] __read_mostly;
51d654e1
MP
442
443/*
444 * a small number of entries is fine, not going to be performance critical.
445 * basically we just need to survive
446 */
447#define BIO_SPLIT_ENTRIES 2
1da177e4
LT
448
449#ifdef CONFIG_HIGHMEM
450/*
20b636bf
AB
451 * remember never ever reenable interrupts between a bvec_kmap_irq and
452 * bvec_kunmap_irq!
1da177e4
LT
453 *
454 * This function MUST be inlined - it plays with the CPU interrupt flags.
1da177e4 455 */
c52440a6
AB
456static __always_inline char *bvec_kmap_irq(struct bio_vec *bvec,
457 unsigned long *flags)
1da177e4
LT
458{
459 unsigned long addr;
460
461 /*
462 * might not be a highmem page, but the preempt/irq count
463 * balancing is a lot nicer this way
464 */
465 local_irq_save(*flags);
466 addr = (unsigned long) kmap_atomic(bvec->bv_page, KM_BIO_SRC_IRQ);
467
468 BUG_ON(addr & ~PAGE_MASK);
469
470 return (char *) addr + bvec->bv_offset;
471}
472
c52440a6
AB
473static __always_inline void bvec_kunmap_irq(char *buffer,
474 unsigned long *flags)
1da177e4
LT
475{
476 unsigned long ptr = (unsigned long) buffer & PAGE_MASK;
477
478 kunmap_atomic((void *) ptr, KM_BIO_SRC_IRQ);
479 local_irq_restore(*flags);
480}
481
482#else
483#define bvec_kmap_irq(bvec, flags) (page_address((bvec)->bv_page) + (bvec)->bv_offset)
484#define bvec_kunmap_irq(buf, flags) do { *(flags) = 0; } while (0)
485#endif
486
c2d08dad 487static inline char *__bio_kmap_irq(struct bio *bio, unsigned short idx,
1da177e4
LT
488 unsigned long *flags)
489{
490 return bvec_kmap_irq(bio_iovec_idx(bio, idx), flags);
491}
492#define __bio_kunmap_irq(buf, flags) bvec_kunmap_irq(buf, flags)
493
494#define bio_kmap_irq(bio, flags) \
495 __bio_kmap_irq((bio), (bio)->bi_idx, (flags))
496#define bio_kunmap_irq(buf,flags) __bio_kunmap_irq(buf, flags)
497
7a67f63b
JA
498/*
499 * Check whether this bio carries any data or not. A NULL bio is allowed.
500 */
501static inline int bio_has_data(struct bio *bio)
502{
503 return bio && bio->bi_io_vec != NULL;
504}
505
8f3d8ba2 506/*
e686307f 507 * BIO list management for use by remapping drivers (e.g. DM or MD) and loop.
8f3d8ba2
CH
508 *
509 * A bio_list anchors a singly-linked list of bios chained through the bi_next
510 * member of the bio. The bio_list also caches the last list member to allow
511 * fast access to the tail.
512 */
513struct bio_list {
514 struct bio *head;
515 struct bio *tail;
516};
517
518static inline int bio_list_empty(const struct bio_list *bl)
519{
520 return bl->head == NULL;
521}
522
523static inline void bio_list_init(struct bio_list *bl)
524{
525 bl->head = bl->tail = NULL;
526}
527
528#define bio_list_for_each(bio, bl) \
529 for (bio = (bl)->head; bio; bio = bio->bi_next)
530
531static inline unsigned bio_list_size(const struct bio_list *bl)
532{
533 unsigned sz = 0;
534 struct bio *bio;
535
536 bio_list_for_each(bio, bl)
537 sz++;
538
539 return sz;
540}
541
542static inline void bio_list_add(struct bio_list *bl, struct bio *bio)
543{
544 bio->bi_next = NULL;
545
546 if (bl->tail)
547 bl->tail->bi_next = bio;
548 else
549 bl->head = bio;
550
551 bl->tail = bio;
552}
553
554static inline void bio_list_add_head(struct bio_list *bl, struct bio *bio)
555{
556 bio->bi_next = bl->head;
557
558 bl->head = bio;
559
560 if (!bl->tail)
561 bl->tail = bio;
562}
563
564static inline void bio_list_merge(struct bio_list *bl, struct bio_list *bl2)
565{
566 if (!bl2->head)
567 return;
568
569 if (bl->tail)
570 bl->tail->bi_next = bl2->head;
571 else
572 bl->head = bl2->head;
573
574 bl->tail = bl2->tail;
575}
576
577static inline void bio_list_merge_head(struct bio_list *bl,
578 struct bio_list *bl2)
579{
580 if (!bl2->head)
581 return;
582
583 if (bl->head)
584 bl2->tail->bi_next = bl->head;
585 else
586 bl->tail = bl2->tail;
587
588 bl->head = bl2->head;
589}
590
13685a16
GU
591static inline struct bio *bio_list_peek(struct bio_list *bl)
592{
593 return bl->head;
594}
595
8f3d8ba2
CH
596static inline struct bio *bio_list_pop(struct bio_list *bl)
597{
598 struct bio *bio = bl->head;
599
600 if (bio) {
601 bl->head = bl->head->bi_next;
602 if (!bl->head)
603 bl->tail = NULL;
604
605 bio->bi_next = NULL;
606 }
607
608 return bio;
609}
610
611static inline struct bio *bio_list_get(struct bio_list *bl)
612{
613 struct bio *bio = bl->head;
614
615 bl->head = bl->tail = NULL;
616
617 return bio;
618}
619
7ba1ba12
MP
620#if defined(CONFIG_BLK_DEV_INTEGRITY)
621
622#define bip_vec_idx(bip, idx) (&(bip->bip_vec[(idx)]))
623#define bip_vec(bip) bip_vec_idx(bip, 0)
624
625#define __bip_for_each_vec(bvl, bip, i, start_idx) \
626 for (bvl = bip_vec_idx((bip), (start_idx)), i = (start_idx); \
627 i < (bip)->bip_vcnt; \
628 bvl++, i++)
629
630#define bip_for_each_vec(bvl, bip, i) \
631 __bip_for_each_vec(bvl, bip, i, (bip)->bip_idx)
632
8deaf721 633#define bio_integrity(bio) (bio->bi_integrity != NULL)
7ba1ba12 634
7878cba9 635extern struct bio_integrity_payload *bio_integrity_alloc_bioset(struct bio *, gfp_t, unsigned int, struct bio_set *);
7ba1ba12 636extern struct bio_integrity_payload *bio_integrity_alloc(struct bio *, gfp_t, unsigned int);
7878cba9 637extern void bio_integrity_free(struct bio *, struct bio_set *);
7ba1ba12
MP
638extern int bio_integrity_add_page(struct bio *, struct page *, unsigned int, unsigned int);
639extern int bio_integrity_enabled(struct bio *bio);
640extern int bio_integrity_set_tag(struct bio *, void *, unsigned int);
641extern int bio_integrity_get_tag(struct bio *, void *, unsigned int);
642extern int bio_integrity_prep(struct bio *);
643extern void bio_integrity_endio(struct bio *, int);
644extern void bio_integrity_advance(struct bio *, unsigned int);
645extern void bio_integrity_trim(struct bio *, unsigned int, unsigned int);
646extern void bio_integrity_split(struct bio *, struct bio_pair *, int);
7878cba9
MP
647extern int bio_integrity_clone(struct bio *, struct bio *, gfp_t, struct bio_set *);
648extern int bioset_integrity_create(struct bio_set *, int);
649extern void bioset_integrity_free(struct bio_set *);
650extern void bio_integrity_init(void);
7ba1ba12
MP
651
652#else /* CONFIG_BLK_DEV_INTEGRITY */
653
654#define bio_integrity(a) (0)
7878cba9 655#define bioset_integrity_create(a, b) (0)
7ba1ba12
MP
656#define bio_integrity_prep(a) (0)
657#define bio_integrity_enabled(a) (0)
7878cba9
MP
658#define bio_integrity_clone(a, b, c, d) (0)
659#define bioset_integrity_free(a) do { } while (0)
660#define bio_integrity_free(a, b) do { } while (0)
7ba1ba12
MP
661#define bio_integrity_endio(a, b) do { } while (0)
662#define bio_integrity_advance(a, b) do { } while (0)
663#define bio_integrity_trim(a, b, c) do { } while (0)
664#define bio_integrity_split(a, b, c) do { } while (0)
665#define bio_integrity_set_tag(a, b, c) do { } while (0)
666#define bio_integrity_get_tag(a, b, c) do { } while (0)
7878cba9 667#define bio_integrity_init(a) do { } while (0)
7ba1ba12
MP
668
669#endif /* CONFIG_BLK_DEV_INTEGRITY */
670
02a5e0ac 671#endif /* CONFIG_BLOCK */
1da177e4 672#endif /* __LINUX_BIO_H */