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block: unify flags for struct bio and struct request
[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/*
7b6d91da
CH		 141 * Request flags. For use in the cmd_flags field of struct request, and in
142 * bi_rw of struct bio. Note that some flags are only valid in either one.
1da177e4 143 */
7b6d91da
CH		 144enum rq_flag_bits {
145 /* common flags */
146 __REQ_WRITE, /* not set, read. set, write */
147 __REQ_FAILFAST_DEV, /* no driver retries of device errors */
148 __REQ_FAILFAST_TRANSPORT, /* no driver retries of transport errors */
149 __REQ_FAILFAST_DRIVER, /* no driver retries of driver errors */
150
151 __REQ_HARDBARRIER, /* may not be passed by drive either */
152 __REQ_SYNC, /* request is sync (sync write or read) */
153 __REQ_META, /* metadata io request */
154 __REQ_DISCARD, /* request to discard sectors */
155 __REQ_NOIDLE, /* don't anticipate more IO after this one */
156
157 /* bio only flags */
158 __REQ_UNPLUG, /* unplug the immediately after submission */
159 __REQ_RAHEAD, /* read ahead, can fail anytime */
160
161 /* request only flags */
162 __REQ_SORTED, /* elevator knows about this request */
163 __REQ_SOFTBARRIER, /* may not be passed by ioscheduler */
164 __REQ_FUA, /* forced unit access */
165 __REQ_NOMERGE, /* don't touch this for merging */
166 __REQ_STARTED, /* drive already may have started this one */
167 __REQ_DONTPREP, /* don't call prep for this one */
168 __REQ_QUEUED, /* uses queueing */
169 __REQ_ELVPRIV, /* elevator private data attached */
170 __REQ_FAILED, /* set if the request failed */
171 __REQ_QUIET, /* don't worry about errors */
172 __REQ_PREEMPT, /* set for "ide_preempt" requests */
173 __REQ_ORDERED_COLOR, /* is before or after barrier */
174 __REQ_ALLOCED, /* request came from our alloc pool */
175 __REQ_COPY_USER, /* contains copies of user pages */
176 __REQ_INTEGRITY, /* integrity metadata has been remapped */
177 __REQ_IO_STAT, /* account I/O stat */
178 __REQ_MIXED_MERGE, /* merge of different types, fail separately */
179 __REQ_NR_BITS, /* stops here */
a82afdfc 180};
213d9417 181
7b6d91da
CH		 182#define REQ_WRITE (1 << __REQ_WRITE)
183#define REQ_FAILFAST_DEV (1 << __REQ_FAILFAST_DEV)
184#define REQ_FAILFAST_TRANSPORT (1 << __REQ_FAILFAST_TRANSPORT)
185#define REQ_FAILFAST_DRIVER (1 << __REQ_FAILFAST_DRIVER)
186#define REQ_HARDBARRIER (1 << __REQ_HARDBARRIER)
187#define REQ_SYNC (1 << __REQ_SYNC)
188#define REQ_META (1 << __REQ_META)
189#define REQ_DISCARD (1 << __REQ_DISCARD)
190#define REQ_NOIDLE (1 << __REQ_NOIDLE)
191
192#define REQ_FAILFAST_MASK \
193 (REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT | REQ_FAILFAST_DRIVER)
194#define REQ_COMMON_MASK \
195 (REQ_WRITE | REQ_FAILFAST_MASK | REQ_HARDBARRIER | REQ_SYNC | \
196 REQ_META| REQ_DISCARD | REQ_NOIDLE)
197
198#define REQ_UNPLUG (1 << __REQ_UNPLUG)
199#define REQ_RAHEAD (1 << __REQ_RAHEAD)
200
201#define REQ_SORTED (1 << __REQ_SORTED)
202#define REQ_SOFTBARRIER (1 << __REQ_SOFTBARRIER)
203#define REQ_FUA (1 << __REQ_FUA)
204#define REQ_NOMERGE (1 << __REQ_NOMERGE)
205#define REQ_STARTED (1 << __REQ_STARTED)
206#define REQ_DONTPREP (1 << __REQ_DONTPREP)
207#define REQ_QUEUED (1 << __REQ_QUEUED)
208#define REQ_ELVPRIV (1 << __REQ_ELVPRIV)
209#define REQ_FAILED (1 << __REQ_FAILED)
210#define REQ_QUIET (1 << __REQ_QUIET)
211#define REQ_PREEMPT (1 << __REQ_PREEMPT)
212#define REQ_ORDERED_COLOR (1 << __REQ_ORDERED_COLOR)
213#define REQ_ALLOCED (1 << __REQ_ALLOCED)
214#define REQ_COPY_USER (1 << __REQ_COPY_USER)
215#define REQ_INTEGRITY (1 << __REQ_INTEGRITY)
216#define REQ_IO_STAT (1 << __REQ_IO_STAT)
217#define REQ_MIXED_MERGE (1 << __REQ_MIXED_MERGE)
1dfa17f4 218
22e2c507
JA		 219/*
220 * upper 16 bits of bi_rw define the io priority of this bio
221 */
222#define BIO_PRIO_SHIFT (8 * sizeof(unsigned long) - IOPRIO_BITS)
223#define bio_prio(bio) ((bio)->bi_rw >> BIO_PRIO_SHIFT)
224#define bio_prio_valid(bio) ioprio_valid(bio_prio(bio))
225
226#define bio_set_prio(bio, prio) do { \
227 WARN_ON(prio >= (1 << IOPRIO_BITS)); \
228 (bio)->bi_rw &= ((1UL << BIO_PRIO_SHIFT) - 1); \
229 (bio)->bi_rw |= ((unsigned long) (prio) << BIO_PRIO_SHIFT); \
230} while (0)
231
1da177e4
LT		 232/*
233 * various member access, note that bio_data should of course not be used
234 * on highmem page vectors
235 */
236#define bio_iovec_idx(bio, idx) (&((bio)->bi_io_vec[(idx)]))
237#define bio_iovec(bio) bio_iovec_idx((bio), (bio)->bi_idx)
238#define bio_page(bio) bio_iovec((bio))->bv_page
239#define bio_offset(bio) bio_iovec((bio))->bv_offset
240#define bio_segments(bio) ((bio)->bi_vcnt - (bio)->bi_idx)
241#define bio_sectors(bio) ((bio)->bi_size >> 9)
7b6d91da
CH		 242#define bio_empty_barrier(bio) \
243 ((bio->bi_rw & REQ_HARDBARRIER) && \
244 !bio_has_data(bio) && \
245 !(bio->bi_rw & REQ_DISCARD))
bf2de6f5 246
2e46e8b2 247static inline unsigned int bio_cur_bytes(struct bio *bio)
bf2de6f5
JA		 248{
249 if (bio->bi_vcnt)
2e46e8b2 250 return bio_iovec(bio)->bv_len;
fb2dce86 251 else /* dataless requests such as discard */
2e46e8b2 252 return bio->bi_size;
bf2de6f5
JA		 253}
254
255static inline void *bio_data(struct bio *bio)
256{
257 if (bio->bi_vcnt)
258 return page_address(bio_page(bio)) + bio_offset(bio);
259
260 return NULL;
261}
1da177e4 262
392ddc32
JA		 263static inline int bio_has_allocated_vec(struct bio *bio)
264{
265 return bio->bi_io_vec && bio->bi_io_vec != bio->bi_inline_vecs;
266}
267
1da177e4
LT		 268/*
269 * will die
270 */
271#define bio_to_phys(bio) (page_to_phys(bio_page((bio))) + (unsigned long) bio_offset((bio)))
272#define bvec_to_phys(bv) (page_to_phys((bv)->bv_page) + (unsigned long) (bv)->bv_offset)
273
274/*
275 * queues that have highmem support enabled may still need to revert to
276 * PIO transfers occasionally and thus map high pages temporarily. For
277 * permanent PIO fall back, user is probably better off disabling highmem
278 * I/O completely on that queue (see ide-dma for example)
279 */
280#define __bio_kmap_atomic(bio, idx, kmtype) \
281 (kmap_atomic(bio_iovec_idx((bio), (idx))->bv_page, kmtype) + \
282 bio_iovec_idx((bio), (idx))->bv_offset)
283
284#define __bio_kunmap_atomic(addr, kmtype) kunmap_atomic(addr, kmtype)
285
286/*
287 * merge helpers etc
288 */
289
290#define __BVEC_END(bio) bio_iovec_idx((bio), (bio)->bi_vcnt - 1)
291#define __BVEC_START(bio) bio_iovec_idx((bio), (bio)->bi_idx)
292
f92131c3
JF		 293/* Default implementation of BIOVEC_PHYS_MERGEABLE */
294#define __BIOVEC_PHYS_MERGEABLE(vec1, vec2) \
295 ((bvec_to_phys((vec1)) + (vec1)->bv_len) == bvec_to_phys((vec2)))
296
1da177e4
LT		 297/*
298 * allow arch override, for eg virtualized architectures (put in asm/io.h)
299 */
300#ifndef BIOVEC_PHYS_MERGEABLE
301#define BIOVEC_PHYS_MERGEABLE(vec1, vec2) \
f92131c3 302 __BIOVEC_PHYS_MERGEABLE(vec1, vec2)
1da177e4
LT		 303#endif
304
1da177e4
LT		 305#define __BIO_SEG_BOUNDARY(addr1, addr2, mask) \
306 (((addr1) | (mask)) == (((addr2) - 1) | (mask)))
307#define BIOVEC_SEG_BOUNDARY(q, b1, b2) \
ae03bf63 308 __BIO_SEG_BOUNDARY(bvec_to_phys((b1)), bvec_to_phys((b2)) + (b2)->bv_len, queue_segment_boundary((q)))
1da177e4
LT		 309#define BIO_SEG_BOUNDARY(q, b1, b2) \
310 BIOVEC_SEG_BOUNDARY((q), __BVEC_END((b1)), __BVEC_START((b2)))
311
6712ecf8 312#define bio_io_error(bio) bio_endio((bio), -EIO)
1da177e4
LT		 313
314/*
315 * drivers should not use the __ version unless they _really_ want to
316 * run through the entire bio and not just pending pieces
317 */
318#define __bio_for_each_segment(bvl, bio, i, start_idx) \
319 for (bvl = bio_iovec_idx((bio), (start_idx)), i = (start_idx); \
320 i < (bio)->bi_vcnt; \
321 bvl++, i++)
322
323#define bio_for_each_segment(bvl, bio, i) \
324 __bio_for_each_segment(bvl, bio, i, (bio)->bi_idx)
325
326/*
327 * get a reference to a bio, so it won't disappear. the intended use is
328 * something like:
329 *
330 * bio_get(bio);
331 * submit_bio(rw, bio);
332 * if (bio->bi_flags ...)
333 * do_something
334 * bio_put(bio);
335 *
336 * without the bio_get(), it could potentially complete I/O before submit_bio
337 * returns. and then bio would be freed memory when if (bio->bi_flags ...)
338 * runs
339 */
340#define bio_get(bio) atomic_inc(&(bio)->bi_cnt)
341
7ba1ba12
MP		 342#if defined(CONFIG_BLK_DEV_INTEGRITY)
343/*
344 * bio integrity payload
345 */
346struct bio_integrity_payload {
347 struct bio *bip_bio; /* parent bio */
7ba1ba12
MP		 348
349 sector_t bip_sector; /* virtual start sector */
350
351 void *bip_buf; /* generated integrity data */
352 bio_end_io_t *bip_end_io; /* saved I/O completion fn */
353
7ba1ba12
MP		 354 unsigned int bip_size;
355
7878cba9 356 unsigned short bip_slab; /* slab the bip came from */
7ba1ba12
MP		 357 unsigned short bip_vcnt; /* # of integrity bio_vecs */
358 unsigned short bip_idx; /* current bip_vec index */
359
360 struct work_struct bip_work; /* I/O completion */
7878cba9 361 struct bio_vec bip_vec[0]; /* embedded bvec array */
7ba1ba12
MP		 362};
363#endif /* CONFIG_BLK_DEV_INTEGRITY */
1da177e4
LT		 364
365/*
366 * A bio_pair is used when we need to split a bio.
367 * This can only happen for a bio that refers to just one
368 * page of data, and in the unusual situation when the
369 * page crosses a chunk/device boundary
370 *
371 * The address of the master bio is stored in bio1.bi_private
372 * The address of the pool the pair was allocated from is stored
373 * in bio2.bi_private
374 */
375struct bio_pair {
7ba1ba12
MP		 376 struct bio bio1, bio2;
377 struct bio_vec bv1, bv2;
378#if defined(CONFIG_BLK_DEV_INTEGRITY)
379 struct bio_integrity_payload bip1, bip2;
380 struct bio_vec iv1, iv2;
381#endif
382 atomic_t cnt;
383 int error;
1da177e4 384};
6feef531 385extern struct bio_pair *bio_split(struct bio *bi, int first_sectors);
1da177e4
LT		 386extern void bio_pair_release(struct bio_pair *dbio);
387
bb799ca0 388extern struct bio_set *bioset_create(unsigned int, unsigned int);
1da177e4
LT		 389extern void bioset_free(struct bio_set *);
390
dd0fc66f 391extern struct bio *bio_alloc(gfp_t, int);
0a0d96b0 392extern struct bio *bio_kmalloc(gfp_t, int);
dd0fc66f 393extern struct bio *bio_alloc_bioset(gfp_t, int, struct bio_set *);
1da177e4 394extern void bio_put(struct bio *);
3676347a 395extern void bio_free(struct bio *, struct bio_set *);
1da177e4 396
6712ecf8 397extern void bio_endio(struct bio *, int);
1da177e4
LT		 398struct request_queue;
399extern int bio_phys_segments(struct request_queue *, struct bio *);
1da177e4
LT		 400
401extern void __bio_clone(struct bio *, struct bio *);
dd0fc66f 402extern struct bio *bio_clone(struct bio *, gfp_t);
1da177e4
LT		 403
404extern void bio_init(struct bio *);
405
406extern int bio_add_page(struct bio *, struct page *, unsigned int,unsigned int);
6e68af66
MC		 407extern int bio_add_pc_page(struct request_queue *, struct bio *, struct page *,
408 unsigned int, unsigned int);
1da177e4 409extern int bio_get_nr_vecs(struct block_device *);
ad3316bf 410extern sector_t bio_sector_offset(struct bio *, unsigned short, unsigned int);
1da177e4 411extern struct bio *bio_map_user(struct request_queue *, struct block_device *,
a3bce90e 412 unsigned long, unsigned int, int, gfp_t);
f1970baf 413struct sg_iovec;
152e283f 414struct rq_map_data;
f1970baf
JB		 415extern struct bio *bio_map_user_iov(struct request_queue *,
416 struct block_device *,
a3bce90e 417 struct sg_iovec *, int, int, gfp_t);
1da177e4 418extern void bio_unmap_user(struct bio *);
df46b9a4 419extern struct bio *bio_map_kern(struct request_queue *, void *, unsigned int,
27496a8c 420 gfp_t);
68154e90
FT		 421extern struct bio *bio_copy_kern(struct request_queue *, void *, unsigned int,
422 gfp_t, int);
1da177e4
LT		 423extern void bio_set_pages_dirty(struct bio *bio);
424extern void bio_check_pages_dirty(struct bio *bio);
2d4dc890
IL		 425
426#ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
427# error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform"
428#endif
429#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
430extern void bio_flush_dcache_pages(struct bio *bi);
431#else
432static inline void bio_flush_dcache_pages(struct bio *bi)
433{
434}
435#endif
436
152e283f
FT		 437extern struct bio *bio_copy_user(struct request_queue *, struct rq_map_data *,
438 unsigned long, unsigned int, int, gfp_t);
439extern struct bio *bio_copy_user_iov(struct request_queue *,
440 struct rq_map_data *, struct sg_iovec *,
a3bce90e 441 int, int, gfp_t);
1da177e4
LT		 442extern int bio_uncopy_user(struct bio *);
443void zero_fill_bio(struct bio *bio);
51d654e1 444extern struct bio_vec *bvec_alloc_bs(gfp_t, int, unsigned long *, struct bio_set *);
bb799ca0 445extern void bvec_free_bs(struct bio_set *, struct bio_vec *, unsigned int);
7ba1ba12 446extern unsigned int bvec_nr_vecs(unsigned short idx);
51d654e1 447
c7c22e4d
JA		 448/*
449 * Allow queuer to specify a completion CPU for this bio
450 */
451static inline void bio_set_completion_cpu(struct bio *bio, unsigned int cpu)
452{
453 bio->bi_comp_cpu = cpu;
454}
455
51d654e1
MP		 456/*
457 * bio_set is used to allow other portions of the IO system to
458 * allocate their own private memory pools for bio and iovec structures.
459 * These memory pools in turn all allocate from the bio_slab
460 * and the bvec_slabs[].
461 */
462#define BIO_POOL_SIZE 2
463#define BIOVEC_NR_POOLS 6
7ff9345f 464#define BIOVEC_MAX_IDX (BIOVEC_NR_POOLS - 1)
51d654e1
MP		 465
466struct bio_set {
1b434498 467 struct kmem_cache *bio_slab;
bb799ca0
JA		 468 unsigned int front_pad;
469
51d654e1 470 mempool_t *bio_pool;
7878cba9
MP		 471#if defined(CONFIG_BLK_DEV_INTEGRITY)
472 mempool_t *bio_integrity_pool;
473#endif
7ff9345f 474 mempool_t *bvec_pool;
51d654e1
MP		 475};
476
477struct biovec_slab {
478 int nr_vecs;
479 char *name;
480 struct kmem_cache *slab;
481};
482
483extern struct bio_set *fs_bio_set;
bb799ca0 484extern struct biovec_slab bvec_slabs[BIOVEC_NR_POOLS] __read_mostly;
51d654e1
MP		 485
486/*
487 * a small number of entries is fine, not going to be performance critical.
488 * basically we just need to survive
489 */
490#define BIO_SPLIT_ENTRIES 2
1da177e4
LT		 491
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);
506 addr = (unsigned long) kmap_atomic(bvec->bv_page, KM_BIO_SRC_IRQ);
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
517 kunmap_atomic((void *) ptr, KM_BIO_SRC_IRQ);
518 local_irq_restore(*flags);
519}
520
521#else
522#define bvec_kmap_irq(bvec, flags) (page_address((bvec)->bv_page) + (bvec)->bv_offset)
523#define bvec_kunmap_irq(buf, flags) do { *(flags) = 0; } while (0)
524#endif
525
c2d08dad 526static inline char *__bio_kmap_irq(struct bio *bio, unsigned short idx,
1da177e4
LT		 527 unsigned long *flags)
528{
529 return bvec_kmap_irq(bio_iovec_idx(bio, idx), flags);
530}
531#define __bio_kunmap_irq(buf, flags) bvec_kunmap_irq(buf, flags)
532
533#define bio_kmap_irq(bio, flags) \
534 __bio_kmap_irq((bio), (bio)->bi_idx, (flags))
535#define bio_kunmap_irq(buf,flags) __bio_kunmap_irq(buf, flags)
536
7a67f63b
JA		 537/*
538 * Check whether this bio carries any data or not. A NULL bio is allowed.
539 */
540static inline int bio_has_data(struct bio *bio)
541{
542 return bio && bio->bi_io_vec != NULL;
543}
544
8f3d8ba2 545/*
e686307f 546 * BIO list management for use by remapping drivers (e.g. DM or MD) and loop.
8f3d8ba2
CH		 547 *
548 * A bio_list anchors a singly-linked list of bios chained through the bi_next
549 * member of the bio. The bio_list also caches the last list member to allow
550 * fast access to the tail.
551 */
552struct bio_list {
553 struct bio *head;
554 struct bio *tail;
555};
556
557static inline int bio_list_empty(const struct bio_list *bl)
558{
559 return bl->head == NULL;
560}
561
562static inline void bio_list_init(struct bio_list *bl)
563{
564 bl->head = bl->tail = NULL;
565}
566
567#define bio_list_for_each(bio, bl) \
568 for (bio = (bl)->head; bio; bio = bio->bi_next)
569
570static inline unsigned bio_list_size(const struct bio_list *bl)
571{
572 unsigned sz = 0;
573 struct bio *bio;
574
575 bio_list_for_each(bio, bl)
576 sz++;
577
578 return sz;
579}
580
581static inline void bio_list_add(struct bio_list *bl, struct bio *bio)
582{
583 bio->bi_next = NULL;
584
585 if (bl->tail)
586 bl->tail->bi_next = bio;
587 else
588 bl->head = bio;
589
590 bl->tail = bio;
591}
592
593static inline void bio_list_add_head(struct bio_list *bl, struct bio *bio)
594{
595 bio->bi_next = bl->head;
596
597 bl->head = bio;
598
599 if (!bl->tail)
600 bl->tail = bio;
601}
602
603static inline void bio_list_merge(struct bio_list *bl, struct bio_list *bl2)
604{
605 if (!bl2->head)
606 return;
607
608 if (bl->tail)
609 bl->tail->bi_next = bl2->head;
610 else
611 bl->head = bl2->head;
612
613 bl->tail = bl2->tail;
614}
615
616static inline void bio_list_merge_head(struct bio_list *bl,
617 struct bio_list *bl2)
618{
619 if (!bl2->head)
620 return;
621
622 if (bl->head)
623 bl2->tail->bi_next = bl->head;
624 else
625 bl->tail = bl2->tail;
626
627 bl->head = bl2->head;
628}
629
13685a16
GU		 630static inline struct bio *bio_list_peek(struct bio_list *bl)
631{
632 return bl->head;
633}
634
8f3d8ba2
CH		 635static inline struct bio *bio_list_pop(struct bio_list *bl)
636{
637 struct bio *bio = bl->head;
638
639 if (bio) {
640 bl->head = bl->head->bi_next;
641 if (!bl->head)
642 bl->tail = NULL;
643
644 bio->bi_next = NULL;
645 }
646
647 return bio;
648}
649
650static inline struct bio *bio_list_get(struct bio_list *bl)
651{
652 struct bio *bio = bl->head;
653
654 bl->head = bl->tail = NULL;
655
656 return bio;
657}
658
7ba1ba12
MP		 659#if defined(CONFIG_BLK_DEV_INTEGRITY)
660
661#define bip_vec_idx(bip, idx) (&(bip->bip_vec[(idx)]))
662#define bip_vec(bip) bip_vec_idx(bip, 0)
663
664#define __bip_for_each_vec(bvl, bip, i, start_idx) \
665 for (bvl = bip_vec_idx((bip), (start_idx)), i = (start_idx); \
666 i < (bip)->bip_vcnt; \
667 bvl++, i++)
668
669#define bip_for_each_vec(bvl, bip, i) \
670 __bip_for_each_vec(bvl, bip, i, (bip)->bip_idx)
671
8deaf721 672#define bio_integrity(bio) (bio->bi_integrity != NULL)
7ba1ba12 673
7878cba9 674extern struct bio_integrity_payload *bio_integrity_alloc_bioset(struct bio *, gfp_t, unsigned int, struct bio_set *);
7ba1ba12 675extern struct bio_integrity_payload *bio_integrity_alloc(struct bio *, gfp_t, unsigned int);
7878cba9 676extern void bio_integrity_free(struct bio *, struct bio_set *);
7ba1ba12
MP		 677extern int bio_integrity_add_page(struct bio *, struct page *, unsigned int, unsigned int);
678extern int bio_integrity_enabled(struct bio *bio);
679extern int bio_integrity_set_tag(struct bio *, void *, unsigned int);
680extern int bio_integrity_get_tag(struct bio *, void *, unsigned int);
681extern int bio_integrity_prep(struct bio *);
682extern void bio_integrity_endio(struct bio *, int);
683extern void bio_integrity_advance(struct bio *, unsigned int);
684extern void bio_integrity_trim(struct bio *, unsigned int, unsigned int);
685extern void bio_integrity_split(struct bio *, struct bio_pair *, int);
7878cba9
MP		 686extern int bio_integrity_clone(struct bio *, struct bio *, gfp_t, struct bio_set *);
687extern int bioset_integrity_create(struct bio_set *, int);
688extern void bioset_integrity_free(struct bio_set *);
689extern void bio_integrity_init(void);
7ba1ba12
MP		 690
691#else /* CONFIG_BLK_DEV_INTEGRITY */
692
693#define bio_integrity(a) (0)
7878cba9 694#define bioset_integrity_create(a, b) (0)
7ba1ba12
MP		 695#define bio_integrity_prep(a) (0)
696#define bio_integrity_enabled(a) (0)
7878cba9
MP		 697#define bio_integrity_clone(a, b, c, d) (0)
698#define bioset_integrity_free(a) do { } while (0)
699#define bio_integrity_free(a, b) do { } while (0)
7ba1ba12
MP		 700#define bio_integrity_endio(a, b) do { } while (0)
701#define bio_integrity_advance(a, b) do { } while (0)
702#define bio_integrity_trim(a, b, c) do { } while (0)
703#define bio_integrity_split(a, b, c) do { } while (0)
704#define bio_integrity_set_tag(a, b, c) do { } while (0)
705#define bio_integrity_get_tag(a, b, c) do { } while (0)
7878cba9 706#define bio_integrity_init(a) do { } while (0)
7ba1ba12
MP		 707
708#endif /* CONFIG_BLK_DEV_INTEGRITY */
709
02a5e0ac 710#endif /* CONFIG_BLOCK */
1da177e4 711#endif /* __LINUX_BIO_H */
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