Line data Source code
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>
25 : #include <linux/ioprio.h>
26 :
27 : #ifdef CONFIG_BLOCK
28 :
29 : #include <asm/io.h>
30 :
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 :
39 : #define BIO_MAX_PAGES 256
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 : */
46 : struct bio_vec {
47 : struct page *bv_page;
48 : unsigned int bv_len;
49 : unsigned int bv_offset;
50 : };
51 :
52 : struct bio_set;
53 : struct bio;
54 : struct bio_integrity_payload;
55 1 : typedef void (bio_end_io_t) (struct bio *, int);
56 1 : typedef void (bio_destructor_t) (struct bio *);
57 1 :
58 : /*
59 : * main unit of I/O for the block layer and lower layers (ie drivers and
60 : * stacking drivers)
61 : */
62 : struct bio {
63 : sector_t bi_sector; /* device address in 512 byte
64 : sectors */
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 : */
78 : unsigned int bi_phys_segments;
79 :
80 : unsigned int bi_size; /* residual I/O count */
81 :
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 :
89 : unsigned int bi_max_vecs; /* max bvl_vecs we can hold */
90 :
91 : unsigned int bi_comp_cpu; /* completion CPU */
92 :
93 : atomic_t bi_cnt; /* pin count */
94 :
95 : struct bio_vec *bi_io_vec; /* the actual vec list */
96 :
97 : bio_end_io_t *bi_end_io;
98 :
99 : void *bi_private;
100 : #if defined(CONFIG_BLK_DEV_INTEGRITY)
101 : struct bio_integrity_payload *bi_integrity; /* data integrity */
102 : #endif
103 :
104 : bio_destructor_t *bi_destructor; /* destructor */
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];
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 */
120 : #define BIO_SEG_VALID 3 /* bi_phys_segments valid */
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 */
125 : #define BIO_CPU_AFFINE 8 /* complete bio on same CPU as submitted */
126 : #define BIO_NULL_MAPPED 9 /* contains invalid user pages */
127 : #define BIO_FS_INTEGRITY 10 /* fs owns integrity data, not block layer */
128 : #define BIO_QUIET 11 /* Make BIO Quiet */
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)
135 : #define BIO_POOL_NONE ((1UL << BIO_POOL_BITS) - 1)
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 : *
143 : * bit 0 -- data direction
144 : * If not set, bio is a read from device. If set, it's a write to device.
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
150 : * Insert a serialization point in the IO queue, forcing previously
151 : * submitted IO to be completed before this one is issued.
152 : * bit 6 -- synchronous I/O hint.
153 : * bit 7 -- Unplug the device immediately after submitting this bio.
154 : * bit 8 -- metadata request
155 : * Used for tracing to differentiate metadata and data IO. May also
156 : * get some preferential treatment in the IO scheduler
157 : * bit 9 -- discard sectors
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.
161 : * Don't want driver retries for any fast fail whatever the reason.
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.
164 : */
165 : enum 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 : };
179 :
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 :
186 : static inline bool bio_rw_flagged(struct bio *bio, enum bio_rw_flags flag)
187 : {
188 : return (bio->bi_rw & (1 << flag)) != 0;
189 : }
190 :
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 :
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)
214 : #define bio_empty_barrier(bio) (bio_rw_flagged(bio, BIO_RW_BARRIER) && !bio_has_data(bio) && !bio_rw_flagged(bio, BIO_RW_DISCARD))
215 :
216 : static inline unsigned int bio_cur_bytes(struct bio *bio)
217 : {
218 : if (bio->bi_vcnt)
219 : return bio_iovec(bio)->bv_len;
220 : else /* dataless requests such as discard */
221 : return bio->bi_size;
222 : }
223 :
224 : static 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 : }
231 :
232 : static 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 :
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 :
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 :
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) \
271 : __BIOVEC_PHYS_MERGEABLE(vec1, vec2)
272 : #endif
273 :
274 : #define __BIO_SEG_BOUNDARY(addr1, addr2, mask) \
275 : (((addr1) | (mask)) == (((addr2) - 1) | (mask)))
276 : #define BIOVEC_SEG_BOUNDARY(q, b1, b2) \
277 : __BIO_SEG_BOUNDARY(bvec_to_phys((b1)), bvec_to_phys((b2)) + (b2)->bv_len, queue_segment_boundary((q)))
278 : #define BIO_SEG_BOUNDARY(q, b1, b2) \
279 : BIOVEC_SEG_BOUNDARY((q), __BVEC_END((b1)), __BVEC_START((b2)))
280 :
281 : #define bio_io_error(bio) bio_endio((bio), -EIO)
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 :
311 : #if defined(CONFIG_BLK_DEV_INTEGRITY)
312 : /*
313 : * bio integrity payload
314 : */
315 : struct bio_integrity_payload {
316 : struct bio *bip_bio; /* parent bio */
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 :
323 : unsigned int bip_size;
324 :
325 : unsigned short bip_slab; /* slab the bip came from */
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 */
330 : struct bio_vec bip_vec[0]; /* embedded bvec array */
331 : };
332 : #endif /* CONFIG_BLK_DEV_INTEGRITY */
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 : */
344 : struct bio_pair {
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;
353 : };
354 : extern struct bio_pair *bio_split(struct bio *bi, int first_sectors);
355 : extern void bio_pair_release(struct bio_pair *dbio);
356 :
357 : extern struct bio_set *bioset_create(unsigned int, unsigned int);
358 : extern void bioset_free(struct bio_set *);
359 :
360 : extern struct bio *bio_alloc(gfp_t, int);
361 : extern struct bio *bio_kmalloc(gfp_t, int);
362 : extern struct bio *bio_alloc_bioset(gfp_t, int, struct bio_set *);
363 : extern void bio_put(struct bio *);
364 : extern void bio_free(struct bio *, struct bio_set *);
365 :
366 : extern void bio_endio(struct bio *, int);
367 : struct request_queue;
368 : extern int bio_phys_segments(struct request_queue *, struct bio *);
369 :
370 : extern void __bio_clone(struct bio *, struct bio *);
371 : extern struct bio *bio_clone(struct bio *, gfp_t);
372 :
373 : extern void bio_init(struct bio *);
374 :
375 : extern int bio_add_page(struct bio *, struct page *, unsigned int,unsigned int);
376 : extern int bio_add_pc_page(struct request_queue *, struct bio *, struct page *,
377 : unsigned int, unsigned int);
378 : extern int bio_get_nr_vecs(struct block_device *);
379 : extern sector_t bio_sector_offset(struct bio *, unsigned short, unsigned int);
380 : extern struct bio *bio_map_user(struct request_queue *, struct block_device *,
381 1 : unsigned long, unsigned int, int, gfp_t);
382 1 : struct sg_iovec;
383 : struct rq_map_data;
384 : extern struct bio *bio_map_user_iov(struct request_queue *,
385 : struct block_device *,
386 : struct sg_iovec *, int, int, gfp_t);
387 : extern void bio_unmap_user(struct bio *);
388 : extern struct bio *bio_map_kern(struct request_queue *, void *, unsigned int,
389 : gfp_t);
390 : extern struct bio *bio_copy_kern(struct request_queue *, void *, unsigned int,
391 : gfp_t, int);
392 : extern void bio_set_pages_dirty(struct bio *bio);
393 : extern void bio_check_pages_dirty(struct bio *bio);
394 :
395 : #ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
396 : # error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform"
397 : #endif
398 : #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
399 : extern void bio_flush_dcache_pages(struct bio *bi);
400 : #else
401 : static inline void bio_flush_dcache_pages(struct bio *bi)
402 : {
403 : }
404 : #endif
405 :
406 : extern struct bio *bio_copy_user(struct request_queue *, struct rq_map_data *,
407 : unsigned long, unsigned int, int, gfp_t);
408 : extern struct bio *bio_copy_user_iov(struct request_queue *,
409 : struct rq_map_data *, struct sg_iovec *,
410 : int, int, gfp_t);
411 : extern int bio_uncopy_user(struct bio *);
412 : void zero_fill_bio(struct bio *bio);
413 : extern struct bio_vec *bvec_alloc_bs(gfp_t, int, unsigned long *, struct bio_set *);
414 : extern void bvec_free_bs(struct bio_set *, struct bio_vec *, unsigned int);
415 : extern unsigned int bvec_nr_vecs(unsigned short idx);
416 :
417 : /*
418 : * Allow queuer to specify a completion CPU for this bio
419 : */
420 : static inline void bio_set_completion_cpu(struct bio *bio, unsigned int cpu)
421 : {
422 : bio->bi_comp_cpu = cpu;
423 : }
424 :
425 : /*
426 : * bio_set is used to allow other portions of the IO system to
427 : * allocate their own private memory pools for bio and iovec structures.
428 : * These memory pools in turn all allocate from the bio_slab
429 : * and the bvec_slabs[].
430 : */
431 : #define BIO_POOL_SIZE 2
432 : #define BIOVEC_NR_POOLS 6
433 : #define BIOVEC_MAX_IDX (BIOVEC_NR_POOLS - 1)
434 :
435 : struct bio_set {
436 : struct kmem_cache *bio_slab;
437 : unsigned int front_pad;
438 :
439 : mempool_t *bio_pool;
440 : #if defined(CONFIG_BLK_DEV_INTEGRITY)
441 : mempool_t *bio_integrity_pool;
442 : #endif
443 : mempool_t *bvec_pool;
444 : };
445 :
446 : struct biovec_slab {
447 : int nr_vecs;
448 : char *name;
449 : struct kmem_cache *slab;
450 : };
451 :
452 : extern struct bio_set *fs_bio_set;
453 : extern struct biovec_slab bvec_slabs[BIOVEC_NR_POOLS] __read_mostly;
454 :
455 : /*
456 : * a small number of entries is fine, not going to be performance critical.
457 : * basically we just need to survive
458 : */
459 : #define BIO_SPLIT_ENTRIES 2
460 :
461 : #ifdef CONFIG_HIGHMEM
462 : /*
463 : * remember never ever reenable interrupts between a bvec_kmap_irq and
464 : * bvec_kunmap_irq!
465 : */
466 : static inline char *bvec_kmap_irq(struct bio_vec *bvec, unsigned long *flags)
467 : {
468 : unsigned long addr;
469 :
470 : /*
471 : * might not be a highmem page, but the preempt/irq count
472 : * balancing is a lot nicer this way
473 : */
474 : local_irq_save(*flags);
475 : addr = (unsigned long) kmap_atomic(bvec->bv_page, KM_BIO_SRC_IRQ);
476 :
477 : BUG_ON(addr & ~PAGE_MASK);
478 :
479 : return (char *) addr + bvec->bv_offset;
480 : }
481 :
482 : static inline void bvec_kunmap_irq(char *buffer, unsigned long *flags)
483 : {
484 : unsigned long ptr = (unsigned long) buffer & PAGE_MASK;
485 :
486 : kunmap_atomic((void *) ptr, KM_BIO_SRC_IRQ);
487 : local_irq_restore(*flags);
488 : }
489 :
490 : #else
491 : #define bvec_kmap_irq(bvec, flags) (page_address((bvec)->bv_page) + (bvec)->bv_offset)
492 : #define bvec_kunmap_irq(buf, flags) do { *(flags) = 0; } while (0)
493 : #endif
494 :
495 : static inline char *__bio_kmap_irq(struct bio *bio, unsigned short idx,
496 : unsigned long *flags)
497 : {
498 : return bvec_kmap_irq(bio_iovec_idx(bio, idx), flags);
499 : }
500 : #define __bio_kunmap_irq(buf, flags) bvec_kunmap_irq(buf, flags)
501 :
502 : #define bio_kmap_irq(bio, flags) \
503 : __bio_kmap_irq((bio), (bio)->bi_idx, (flags))
504 : #define bio_kunmap_irq(buf,flags) __bio_kunmap_irq(buf, flags)
505 :
506 : /*
507 : * Check whether this bio carries any data or not. A NULL bio is allowed.
508 : */
509 : static inline int bio_has_data(struct bio *bio)
510 : {
511 : return bio && bio->bi_io_vec != NULL;
512 : }
513 :
514 : /*
515 : * BIO list management for use by remapping drivers (e.g. DM or MD) and loop.
516 : *
517 : * A bio_list anchors a singly-linked list of bios chained through the bi_next
518 : * member of the bio. The bio_list also caches the last list member to allow
519 : * fast access to the tail.
520 : */
521 : struct bio_list {
522 : struct bio *head;
523 : struct bio *tail;
524 : };
525 :
526 : static inline int bio_list_empty(const struct bio_list *bl)
527 : {
528 : return bl->head == NULL;
529 : }
530 :
531 : static inline void bio_list_init(struct bio_list *bl)
532 : {
533 : bl->head = bl->tail = NULL;
534 : }
535 :
536 : #define bio_list_for_each(bio, bl) \
537 : for (bio = (bl)->head; bio; bio = bio->bi_next)
538 :
539 : static inline unsigned bio_list_size(const struct bio_list *bl)
540 : {
541 : unsigned sz = 0;
542 : struct bio *bio;
543 :
544 : bio_list_for_each(bio, bl)
545 : sz++;
546 :
547 : return sz;
548 : }
549 :
550 : static inline void bio_list_add(struct bio_list *bl, struct bio *bio)
551 : {
552 : bio->bi_next = NULL;
553 :
554 : if (bl->tail)
555 : bl->tail->bi_next = bio;
556 : else
557 : bl->head = bio;
558 :
559 : bl->tail = bio;
560 : }
561 :
562 : static inline void bio_list_add_head(struct bio_list *bl, struct bio *bio)
563 : {
564 : bio->bi_next = bl->head;
565 :
566 : bl->head = bio;
567 :
568 : if (!bl->tail)
569 : bl->tail = bio;
570 : }
571 :
572 : static inline void bio_list_merge(struct bio_list *bl, struct bio_list *bl2)
573 : {
574 : if (!bl2->head)
575 : return;
576 :
577 : if (bl->tail)
578 : bl->tail->bi_next = bl2->head;
579 : else
580 : bl->head = bl2->head;
581 :
582 : bl->tail = bl2->tail;
583 : }
584 :
585 : static inline void bio_list_merge_head(struct bio_list *bl,
586 : struct bio_list *bl2)
587 : {
588 : if (!bl2->head)
589 : return;
590 :
591 : if (bl->head)
592 : bl2->tail->bi_next = bl->head;
593 : else
594 : bl->tail = bl2->tail;
595 :
596 : bl->head = bl2->head;
597 : }
598 :
599 : static inline struct bio *bio_list_peek(struct bio_list *bl)
600 : {
601 : return bl->head;
602 : }
603 :
604 : static inline struct bio *bio_list_pop(struct bio_list *bl)
605 : {
606 : struct bio *bio = bl->head;
607 :
608 : if (bio) {
609 : bl->head = bl->head->bi_next;
610 : if (!bl->head)
611 : bl->tail = NULL;
612 :
613 : bio->bi_next = NULL;
614 : }
615 :
616 : return bio;
617 : }
618 :
619 : static inline struct bio *bio_list_get(struct bio_list *bl)
620 : {
621 : struct bio *bio = bl->head;
622 :
623 : bl->head = bl->tail = NULL;
624 :
625 : return bio;
626 : }
627 :
628 : #if defined(CONFIG_BLK_DEV_INTEGRITY)
629 :
630 : #define bip_vec_idx(bip, idx) (&(bip->bip_vec[(idx)]))
631 : #define bip_vec(bip) bip_vec_idx(bip, 0)
632 :
633 : #define __bip_for_each_vec(bvl, bip, i, start_idx) \
634 : for (bvl = bip_vec_idx((bip), (start_idx)), i = (start_idx); \
635 : i < (bip)->bip_vcnt; \
636 : bvl++, i++)
637 :
638 : #define bip_for_each_vec(bvl, bip, i) \
639 : __bip_for_each_vec(bvl, bip, i, (bip)->bip_idx)
640 :
641 : #define bio_integrity(bio) (bio->bi_integrity != NULL)
642 :
643 : extern struct bio_integrity_payload *bio_integrity_alloc_bioset(struct bio *, gfp_t, unsigned int, struct bio_set *);
644 : extern struct bio_integrity_payload *bio_integrity_alloc(struct bio *, gfp_t, unsigned int);
645 : extern void bio_integrity_free(struct bio *, struct bio_set *);
646 : extern int bio_integrity_add_page(struct bio *, struct page *, unsigned int, unsigned int);
647 : extern int bio_integrity_enabled(struct bio *bio);
648 : extern int bio_integrity_set_tag(struct bio *, void *, unsigned int);
649 : extern int bio_integrity_get_tag(struct bio *, void *, unsigned int);
650 : extern int bio_integrity_prep(struct bio *);
651 : extern void bio_integrity_endio(struct bio *, int);
652 : extern void bio_integrity_advance(struct bio *, unsigned int);
653 : extern void bio_integrity_trim(struct bio *, unsigned int, unsigned int);
654 : extern void bio_integrity_split(struct bio *, struct bio_pair *, int);
655 : extern int bio_integrity_clone(struct bio *, struct bio *, gfp_t, struct bio_set *);
656 : extern int bioset_integrity_create(struct bio_set *, int);
657 : extern void bioset_integrity_free(struct bio_set *);
658 : extern void bio_integrity_init(void);
659 :
660 : #else /* CONFIG_BLK_DEV_INTEGRITY */
661 :
662 : #define bio_integrity(a) (0)
663 : #define bioset_integrity_create(a, b) (0)
664 : #define bio_integrity_prep(a) (0)
665 : #define bio_integrity_enabled(a) (0)
666 : #define bio_integrity_clone(a, b, c, d) (0)
667 : #define bioset_integrity_free(a) do { } while (0)
668 : #define bio_integrity_free(a, b) do { } while (0)
669 : #define bio_integrity_endio(a, b) do { } while (0)
670 : #define bio_integrity_advance(a, b) do { } while (0)
671 : #define bio_integrity_trim(a, b, c) do { } while (0)
672 : #define bio_integrity_split(a, b, c) do { } while (0)
673 : #define bio_integrity_set_tag(a, b, c) do { } while (0)
674 : #define bio_integrity_get_tag(a, b, c) do { } while (0)
675 : #define bio_integrity_init(a) do { } while (0)
676 :
677 : #endif /* CONFIG_BLK_DEV_INTEGRITY */
678 :
679 : #endif /* CONFIG_BLOCK */
680 : #endif /* __LINUX_BIO_H */
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