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TOMOYO Linux Cross Reference
Linux/include/linux/bio.h

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  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 #include <linux/bug.h>
 27 
 28 #ifdef CONFIG_BLOCK
 29 
 30 #include <asm/io.h>
 31 
 32 /* struct bio, bio_vec and BIO_* flags are defined in blk_types.h */
 33 #include <linux/blk_types.h>
 34 
 35 #define BIO_DEBUG
 36 
 37 #ifdef BIO_DEBUG
 38 #define BIO_BUG_ON      BUG_ON
 39 #else
 40 #define BIO_BUG_ON
 41 #endif
 42 
 43 #define BIO_MAX_PAGES           256
 44 #define BIO_MAX_SIZE            (BIO_MAX_PAGES << PAGE_CACHE_SHIFT)
 45 #define BIO_MAX_SECTORS         (BIO_MAX_SIZE >> 9)
 46 
 47 /*
 48  * upper 16 bits of bi_rw define the io priority of this bio
 49  */
 50 #define BIO_PRIO_SHIFT  (8 * sizeof(unsigned long) - IOPRIO_BITS)
 51 #define bio_prio(bio)   ((bio)->bi_rw >> BIO_PRIO_SHIFT)
 52 #define bio_prio_valid(bio)     ioprio_valid(bio_prio(bio))
 53 
 54 #define bio_set_prio(bio, prio)         do {                    \
 55         WARN_ON(prio >= (1 << IOPRIO_BITS));                    \
 56         (bio)->bi_rw &= ((1UL << BIO_PRIO_SHIFT) - 1);          \
 57         (bio)->bi_rw |= ((unsigned long) (prio) << BIO_PRIO_SHIFT);     \
 58 } while (0)
 59 
 60 /*
 61  * various member access, note that bio_data should of course not be used
 62  * on highmem page vectors
 63  */
 64 #define __bvec_iter_bvec(bvec, iter)    (&(bvec)[(iter).bi_idx])
 65 
 66 #define bvec_iter_page(bvec, iter)                              \
 67         (__bvec_iter_bvec((bvec), (iter))->bv_page)
 68 
 69 #define bvec_iter_len(bvec, iter)                               \
 70         min((iter).bi_size,                                     \
 71             __bvec_iter_bvec((bvec), (iter))->bv_len - (iter).bi_bvec_done)
 72 
 73 #define bvec_iter_offset(bvec, iter)                            \
 74         (__bvec_iter_bvec((bvec), (iter))->bv_offset + (iter).bi_bvec_done)
 75 
 76 #define bvec_iter_bvec(bvec, iter)                              \
 77 ((struct bio_vec) {                                             \
 78         .bv_page        = bvec_iter_page((bvec), (iter)),       \
 79         .bv_len         = bvec_iter_len((bvec), (iter)),        \
 80         .bv_offset      = bvec_iter_offset((bvec), (iter)),     \
 81 })
 82 
 83 #define bio_iter_iovec(bio, iter)                               \
 84         bvec_iter_bvec((bio)->bi_io_vec, (iter))
 85 
 86 #define bio_iter_page(bio, iter)                                \
 87         bvec_iter_page((bio)->bi_io_vec, (iter))
 88 #define bio_iter_len(bio, iter)                                 \
 89         bvec_iter_len((bio)->bi_io_vec, (iter))
 90 #define bio_iter_offset(bio, iter)                              \
 91         bvec_iter_offset((bio)->bi_io_vec, (iter))
 92 
 93 #define bio_page(bio)           bio_iter_page((bio), (bio)->bi_iter)
 94 #define bio_offset(bio)         bio_iter_offset((bio), (bio)->bi_iter)
 95 #define bio_iovec(bio)          bio_iter_iovec((bio), (bio)->bi_iter)
 96 
 97 #define bio_multiple_segments(bio)                              \
 98         ((bio)->bi_iter.bi_size != bio_iovec(bio).bv_len)
 99 #define bio_sectors(bio)        ((bio)->bi_iter.bi_size >> 9)
100 #define bio_end_sector(bio)     ((bio)->bi_iter.bi_sector + bio_sectors((bio)))
101 
102 /*
103  * Check whether this bio carries any data or not. A NULL bio is allowed.
104  */
105 static inline bool bio_has_data(struct bio *bio)
106 {
107         if (bio &&
108             bio->bi_iter.bi_size &&
109             !(bio->bi_rw & REQ_DISCARD))
110                 return true;
111 
112         return false;
113 }
114 
115 static inline bool bio_is_rw(struct bio *bio)
116 {
117         if (!bio_has_data(bio))
118                 return false;
119 
120         if (bio->bi_rw & BIO_NO_ADVANCE_ITER_MASK)
121                 return false;
122 
123         return true;
124 }
125 
126 static inline bool bio_mergeable(struct bio *bio)
127 {
128         if (bio->bi_rw & REQ_NOMERGE_FLAGS)
129                 return false;
130 
131         return true;
132 }
133 
134 static inline unsigned int bio_cur_bytes(struct bio *bio)
135 {
136         if (bio_has_data(bio))
137                 return bio_iovec(bio).bv_len;
138         else /* dataless requests such as discard */
139                 return bio->bi_iter.bi_size;
140 }
141 
142 static inline void *bio_data(struct bio *bio)
143 {
144         if (bio_has_data(bio))
145                 return page_address(bio_page(bio)) + bio_offset(bio);
146 
147         return NULL;
148 }
149 
150 /*
151  * will die
152  */
153 #define bio_to_phys(bio)        (page_to_phys(bio_page((bio))) + (unsigned long) bio_offset((bio)))
154 #define bvec_to_phys(bv)        (page_to_phys((bv)->bv_page) + (unsigned long) (bv)->bv_offset)
155 
156 /*
157  * queues that have highmem support enabled may still need to revert to
158  * PIO transfers occasionally and thus map high pages temporarily. For
159  * permanent PIO fall back, user is probably better off disabling highmem
160  * I/O completely on that queue (see ide-dma for example)
161  */
162 #define __bio_kmap_atomic(bio, iter)                            \
163         (kmap_atomic(bio_iter_iovec((bio), (iter)).bv_page) +   \
164                 bio_iter_iovec((bio), (iter)).bv_offset)
165 
166 #define __bio_kunmap_atomic(addr)       kunmap_atomic(addr)
167 
168 /*
169  * merge helpers etc
170  */
171 
172 /* Default implementation of BIOVEC_PHYS_MERGEABLE */
173 #define __BIOVEC_PHYS_MERGEABLE(vec1, vec2)     \
174         ((bvec_to_phys((vec1)) + (vec1)->bv_len) == bvec_to_phys((vec2)))
175 
176 /*
177  * allow arch override, for eg virtualized architectures (put in asm/io.h)
178  */
179 #ifndef BIOVEC_PHYS_MERGEABLE
180 #define BIOVEC_PHYS_MERGEABLE(vec1, vec2)       \
181         __BIOVEC_PHYS_MERGEABLE(vec1, vec2)
182 #endif
183 
184 #define __BIO_SEG_BOUNDARY(addr1, addr2, mask) \
185         (((addr1) | (mask)) == (((addr2) - 1) | (mask)))
186 #define BIOVEC_SEG_BOUNDARY(q, b1, b2) \
187         __BIO_SEG_BOUNDARY(bvec_to_phys((b1)), bvec_to_phys((b2)) + (b2)->bv_len, queue_segment_boundary((q)))
188 
189 #define bio_io_error(bio) bio_endio((bio), -EIO)
190 
191 /*
192  * drivers should _never_ use the all version - the bio may have been split
193  * before it got to the driver and the driver won't own all of it
194  */
195 #define bio_for_each_segment_all(bvl, bio, i)                           \
196         for (i = 0, bvl = (bio)->bi_io_vec; i < (bio)->bi_vcnt; i++, bvl++)
197 
198 static inline void bvec_iter_advance(struct bio_vec *bv, struct bvec_iter *iter,
199                                      unsigned bytes)
200 {
201         WARN_ONCE(bytes > iter->bi_size,
202                   "Attempted to advance past end of bvec iter\n");
203 
204         while (bytes) {
205                 unsigned len = min(bytes, bvec_iter_len(bv, *iter));
206 
207                 bytes -= len;
208                 iter->bi_size -= len;
209                 iter->bi_bvec_done += len;
210 
211                 if (iter->bi_bvec_done == __bvec_iter_bvec(bv, *iter)->bv_len) {
212                         iter->bi_bvec_done = 0;
213                         iter->bi_idx++;
214                 }
215         }
216 }
217 
218 #define for_each_bvec(bvl, bio_vec, iter, start)                        \
219         for (iter = (start);                                            \
220              (iter).bi_size &&                                          \
221                 ((bvl = bvec_iter_bvec((bio_vec), (iter))), 1); \
222              bvec_iter_advance((bio_vec), &(iter), (bvl).bv_len))
223 
224 
225 static inline void bio_advance_iter(struct bio *bio, struct bvec_iter *iter,
226                                     unsigned bytes)
227 {
228         iter->bi_sector += bytes >> 9;
229 
230         if (bio->bi_rw & BIO_NO_ADVANCE_ITER_MASK)
231                 iter->bi_size -= bytes;
232         else
233                 bvec_iter_advance(bio->bi_io_vec, iter, bytes);
234 }
235 
236 #define __bio_for_each_segment(bvl, bio, iter, start)                   \
237         for (iter = (start);                                            \
238              (iter).bi_size &&                                          \
239                 ((bvl = bio_iter_iovec((bio), (iter))), 1);             \
240              bio_advance_iter((bio), &(iter), (bvl).bv_len))
241 
242 #define bio_for_each_segment(bvl, bio, iter)                            \
243         __bio_for_each_segment(bvl, bio, iter, (bio)->bi_iter)
244 
245 #define bio_iter_last(bvec, iter) ((iter).bi_size == (bvec).bv_len)
246 
247 static inline unsigned bio_segments(struct bio *bio)
248 {
249         unsigned segs = 0;
250         struct bio_vec bv;
251         struct bvec_iter iter;
252 
253         /*
254          * We special case discard/write same, because they interpret bi_size
255          * differently:
256          */
257 
258         if (bio->bi_rw & REQ_DISCARD)
259                 return 1;
260 
261         if (bio->bi_rw & REQ_WRITE_SAME)
262                 return 1;
263 
264         bio_for_each_segment(bv, bio, iter)
265                 segs++;
266 
267         return segs;
268 }
269 
270 /*
271  * get a reference to a bio, so it won't disappear. the intended use is
272  * something like:
273  *
274  * bio_get(bio);
275  * submit_bio(rw, bio);
276  * if (bio->bi_flags ...)
277  *      do_something
278  * bio_put(bio);
279  *
280  * without the bio_get(), it could potentially complete I/O before submit_bio
281  * returns. and then bio would be freed memory when if (bio->bi_flags ...)
282  * runs
283  */
284 #define bio_get(bio)    atomic_inc(&(bio)->bi_cnt)
285 
286 #if defined(CONFIG_BLK_DEV_INTEGRITY)
287 /*
288  * bio integrity payload
289  */
290 struct bio_integrity_payload {
291         struct bio              *bip_bio;       /* parent bio */
292 
293         struct bvec_iter        bip_iter;
294 
295         /* kill - should just use bip_vec */
296         void                    *bip_buf;       /* generated integrity data */
297 
298         bio_end_io_t            *bip_end_io;    /* saved I/O completion fn */
299 
300         unsigned short          bip_slab;       /* slab the bip came from */
301         unsigned short          bip_vcnt;       /* # of integrity bio_vecs */
302         unsigned                bip_owns_buf:1; /* should free bip_buf */
303 
304         struct work_struct      bip_work;       /* I/O completion */
305 
306         struct bio_vec          *bip_vec;
307         struct bio_vec          bip_inline_vecs[0];/* embedded bvec array */
308 };
309 #endif /* CONFIG_BLK_DEV_INTEGRITY */
310 
311 extern void bio_trim(struct bio *bio, int offset, int size);
312 extern struct bio *bio_split(struct bio *bio, int sectors,
313                              gfp_t gfp, struct bio_set *bs);
314 
315 /**
316  * bio_next_split - get next @sectors from a bio, splitting if necessary
317  * @bio:        bio to split
318  * @sectors:    number of sectors to split from the front of @bio
319  * @gfp:        gfp mask
320  * @bs:         bio set to allocate from
321  *
322  * Returns a bio representing the next @sectors of @bio - if the bio is smaller
323  * than @sectors, returns the original bio unchanged.
324  */
325 static inline struct bio *bio_next_split(struct bio *bio, int sectors,
326                                          gfp_t gfp, struct bio_set *bs)
327 {
328         if (sectors >= bio_sectors(bio))
329                 return bio;
330 
331         return bio_split(bio, sectors, gfp, bs);
332 }
333 
334 extern struct bio_set *bioset_create(unsigned int, unsigned int);
335 extern void bioset_free(struct bio_set *);
336 extern mempool_t *biovec_create_pool(struct bio_set *bs, int pool_entries);
337 
338 extern struct bio *bio_alloc_bioset(gfp_t, int, struct bio_set *);
339 extern void bio_put(struct bio *);
340 
341 extern void __bio_clone_fast(struct bio *, struct bio *);
342 extern struct bio *bio_clone_fast(struct bio *, gfp_t, struct bio_set *);
343 extern struct bio *bio_clone_bioset(struct bio *, gfp_t, struct bio_set *bs);
344 
345 extern struct bio_set *fs_bio_set;
346 unsigned int bio_integrity_tag_size(struct bio *bio);
347 
348 static inline struct bio *bio_alloc(gfp_t gfp_mask, unsigned int nr_iovecs)
349 {
350         return bio_alloc_bioset(gfp_mask, nr_iovecs, fs_bio_set);
351 }
352 
353 static inline struct bio *bio_clone(struct bio *bio, gfp_t gfp_mask)
354 {
355         return bio_clone_bioset(bio, gfp_mask, fs_bio_set);
356 }
357 
358 static inline struct bio *bio_kmalloc(gfp_t gfp_mask, unsigned int nr_iovecs)
359 {
360         return bio_alloc_bioset(gfp_mask, nr_iovecs, NULL);
361 }
362 
363 static inline struct bio *bio_clone_kmalloc(struct bio *bio, gfp_t gfp_mask)
364 {
365         return bio_clone_bioset(bio, gfp_mask, NULL);
366 
367 }
368 
369 extern void bio_endio(struct bio *, int);
370 extern void bio_endio_nodec(struct bio *, int);
371 struct request_queue;
372 extern int bio_phys_segments(struct request_queue *, struct bio *);
373 
374 extern int submit_bio_wait(int rw, struct bio *bio);
375 extern void bio_advance(struct bio *, unsigned);
376 
377 extern void bio_init(struct bio *);
378 extern void bio_reset(struct bio *);
379 void bio_chain(struct bio *, struct bio *);
380 
381 extern int bio_add_page(struct bio *, struct page *, unsigned int,unsigned int);
382 extern int bio_add_pc_page(struct request_queue *, struct bio *, struct page *,
383                            unsigned int, unsigned int);
384 extern int bio_get_nr_vecs(struct block_device *);
385 extern struct bio *bio_map_user(struct request_queue *, struct block_device *,
386                                 unsigned long, unsigned int, int, gfp_t);
387 struct sg_iovec;
388 struct rq_map_data;
389 extern struct bio *bio_map_user_iov(struct request_queue *,
390                                     struct block_device *,
391                                     struct sg_iovec *, int, int, gfp_t);
392 extern void bio_unmap_user(struct bio *);
393 extern struct bio *bio_map_kern(struct request_queue *, void *, unsigned int,
394                                 gfp_t);
395 extern struct bio *bio_copy_kern(struct request_queue *, void *, unsigned int,
396                                  gfp_t, int);
397 extern void bio_set_pages_dirty(struct bio *bio);
398 extern void bio_check_pages_dirty(struct bio *bio);
399 
400 #ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
401 # error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform"
402 #endif
403 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
404 extern void bio_flush_dcache_pages(struct bio *bi);
405 #else
406 static inline void bio_flush_dcache_pages(struct bio *bi)
407 {
408 }
409 #endif
410 
411 extern void bio_copy_data(struct bio *dst, struct bio *src);
412 extern int bio_alloc_pages(struct bio *bio, gfp_t gfp);
413 
414 extern struct bio *bio_copy_user(struct request_queue *, struct rq_map_data *,
415                                  unsigned long, unsigned int, int, gfp_t);
416 extern struct bio *bio_copy_user_iov(struct request_queue *,
417                                      struct rq_map_data *, struct sg_iovec *,
418                                      int, int, gfp_t);
419 extern int bio_uncopy_user(struct bio *);
420 void zero_fill_bio(struct bio *bio);
421 extern struct bio_vec *bvec_alloc(gfp_t, int, unsigned long *, mempool_t *);
422 extern void bvec_free(mempool_t *, struct bio_vec *, unsigned int);
423 extern unsigned int bvec_nr_vecs(unsigned short idx);
424 
425 #ifdef CONFIG_BLK_CGROUP
426 int bio_associate_current(struct bio *bio);
427 void bio_disassociate_task(struct bio *bio);
428 #else   /* CONFIG_BLK_CGROUP */
429 static inline int bio_associate_current(struct bio *bio) { return -ENOENT; }
430 static inline void bio_disassociate_task(struct bio *bio) { }
431 #endif  /* CONFIG_BLK_CGROUP */
432 
433 #ifdef CONFIG_HIGHMEM
434 /*
435  * remember never ever reenable interrupts between a bvec_kmap_irq and
436  * bvec_kunmap_irq!
437  */
438 static inline char *bvec_kmap_irq(struct bio_vec *bvec, unsigned long *flags)
439 {
440         unsigned long addr;
441 
442         /*
443          * might not be a highmem page, but the preempt/irq count
444          * balancing is a lot nicer this way
445          */
446         local_irq_save(*flags);
447         addr = (unsigned long) kmap_atomic(bvec->bv_page);
448 
449         BUG_ON(addr & ~PAGE_MASK);
450 
451         return (char *) addr + bvec->bv_offset;
452 }
453 
454 static inline void bvec_kunmap_irq(char *buffer, unsigned long *flags)
455 {
456         unsigned long ptr = (unsigned long) buffer & PAGE_MASK;
457 
458         kunmap_atomic((void *) ptr);
459         local_irq_restore(*flags);
460 }
461 
462 #else
463 static inline char *bvec_kmap_irq(struct bio_vec *bvec, unsigned long *flags)
464 {
465         return page_address(bvec->bv_page) + bvec->bv_offset;
466 }
467 
468 static inline void bvec_kunmap_irq(char *buffer, unsigned long *flags)
469 {
470         *flags = 0;
471 }
472 #endif
473 
474 static inline char *__bio_kmap_irq(struct bio *bio, struct bvec_iter iter,
475                                    unsigned long *flags)
476 {
477         return bvec_kmap_irq(&bio_iter_iovec(bio, iter), flags);
478 }
479 #define __bio_kunmap_irq(buf, flags)    bvec_kunmap_irq(buf, flags)
480 
481 #define bio_kmap_irq(bio, flags) \
482         __bio_kmap_irq((bio), (bio)->bi_iter, (flags))
483 #define bio_kunmap_irq(buf,flags)       __bio_kunmap_irq(buf, flags)
484 
485 /*
486  * BIO list management for use by remapping drivers (e.g. DM or MD) and loop.
487  *
488  * A bio_list anchors a singly-linked list of bios chained through the bi_next
489  * member of the bio.  The bio_list also caches the last list member to allow
490  * fast access to the tail.
491  */
492 struct bio_list {
493         struct bio *head;
494         struct bio *tail;
495 };
496 
497 static inline int bio_list_empty(const struct bio_list *bl)
498 {
499         return bl->head == NULL;
500 }
501 
502 static inline void bio_list_init(struct bio_list *bl)
503 {
504         bl->head = bl->tail = NULL;
505 }
506 
507 #define BIO_EMPTY_LIST  { NULL, NULL }
508 
509 #define bio_list_for_each(bio, bl) \
510         for (bio = (bl)->head; bio; bio = bio->bi_next)
511 
512 static inline unsigned bio_list_size(const struct bio_list *bl)
513 {
514         unsigned sz = 0;
515         struct bio *bio;
516 
517         bio_list_for_each(bio, bl)
518                 sz++;
519 
520         return sz;
521 }
522 
523 static inline void bio_list_add(struct bio_list *bl, struct bio *bio)
524 {
525         bio->bi_next = NULL;
526 
527         if (bl->tail)
528                 bl->tail->bi_next = bio;
529         else
530                 bl->head = bio;
531 
532         bl->tail = bio;
533 }
534 
535 static inline void bio_list_add_head(struct bio_list *bl, struct bio *bio)
536 {
537         bio->bi_next = bl->head;
538 
539         bl->head = bio;
540 
541         if (!bl->tail)
542                 bl->tail = bio;
543 }
544 
545 static inline void bio_list_merge(struct bio_list *bl, struct bio_list *bl2)
546 {
547         if (!bl2->head)
548                 return;
549 
550         if (bl->tail)
551                 bl->tail->bi_next = bl2->head;
552         else
553                 bl->head = bl2->head;
554 
555         bl->tail = bl2->tail;
556 }
557 
558 static inline void bio_list_merge_head(struct bio_list *bl,
559                                        struct bio_list *bl2)
560 {
561         if (!bl2->head)
562                 return;
563 
564         if (bl->head)
565                 bl2->tail->bi_next = bl->head;
566         else
567                 bl->tail = bl2->tail;
568 
569         bl->head = bl2->head;
570 }
571 
572 static inline struct bio *bio_list_peek(struct bio_list *bl)
573 {
574         return bl->head;
575 }
576 
577 static inline struct bio *bio_list_pop(struct bio_list *bl)
578 {
579         struct bio *bio = bl->head;
580 
581         if (bio) {
582                 bl->head = bl->head->bi_next;
583                 if (!bl->head)
584                         bl->tail = NULL;
585 
586                 bio->bi_next = NULL;
587         }
588 
589         return bio;
590 }
591 
592 static inline struct bio *bio_list_get(struct bio_list *bl)
593 {
594         struct bio *bio = bl->head;
595 
596         bl->head = bl->tail = NULL;
597 
598         return bio;
599 }
600 
601 /*
602  * bio_set is used to allow other portions of the IO system to
603  * allocate their own private memory pools for bio and iovec structures.
604  * These memory pools in turn all allocate from the bio_slab
605  * and the bvec_slabs[].
606  */
607 #define BIO_POOL_SIZE 2
608 #define BIOVEC_NR_POOLS 6
609 #define BIOVEC_MAX_IDX  (BIOVEC_NR_POOLS - 1)
610 
611 struct bio_set {
612         struct kmem_cache *bio_slab;
613         unsigned int front_pad;
614 
615         mempool_t *bio_pool;
616         mempool_t *bvec_pool;
617 #if defined(CONFIG_BLK_DEV_INTEGRITY)
618         mempool_t *bio_integrity_pool;
619         mempool_t *bvec_integrity_pool;
620 #endif
621 
622         /*
623          * Deadlock avoidance for stacking block drivers: see comments in
624          * bio_alloc_bioset() for details
625          */
626         spinlock_t              rescue_lock;
627         struct bio_list         rescue_list;
628         struct work_struct      rescue_work;
629         struct workqueue_struct *rescue_workqueue;
630 };
631 
632 struct biovec_slab {
633         int nr_vecs;
634         char *name;
635         struct kmem_cache *slab;
636 };
637 
638 /*
639  * a small number of entries is fine, not going to be performance critical.
640  * basically we just need to survive
641  */
642 #define BIO_SPLIT_ENTRIES 2
643 
644 #if defined(CONFIG_BLK_DEV_INTEGRITY)
645 
646 
647 
648 #define bip_vec_idx(bip, idx)   (&(bip->bip_vec[(idx)]))
649 
650 #define bip_for_each_vec(bvl, bip, iter)                                \
651         for_each_bvec(bvl, (bip)->bip_vec, iter, (bip)->bip_iter)
652 
653 #define bio_for_each_integrity_vec(_bvl, _bio, _iter)                   \
654         for_each_bio(_bio)                                              \
655                 bip_for_each_vec(_bvl, _bio->bi_integrity, _iter)
656 
657 #define bio_integrity(bio) (bio->bi_integrity != NULL)
658 
659 extern struct bio_integrity_payload *bio_integrity_alloc(struct bio *, gfp_t, unsigned int);
660 extern void bio_integrity_free(struct bio *);
661 extern int bio_integrity_add_page(struct bio *, struct page *, unsigned int, unsigned int);
662 extern int bio_integrity_enabled(struct bio *bio);
663 extern int bio_integrity_set_tag(struct bio *, void *, unsigned int);
664 extern int bio_integrity_get_tag(struct bio *, void *, unsigned int);
665 extern int bio_integrity_prep(struct bio *);
666 extern void bio_integrity_endio(struct bio *, int);
667 extern void bio_integrity_advance(struct bio *, unsigned int);
668 extern void bio_integrity_trim(struct bio *, unsigned int, unsigned int);
669 extern int bio_integrity_clone(struct bio *, struct bio *, gfp_t);
670 extern int bioset_integrity_create(struct bio_set *, int);
671 extern void bioset_integrity_free(struct bio_set *);
672 extern void bio_integrity_init(void);
673 
674 #else /* CONFIG_BLK_DEV_INTEGRITY */
675 
676 static inline int bio_integrity(struct bio *bio)
677 {
678         return 0;
679 }
680 
681 static inline int bio_integrity_enabled(struct bio *bio)
682 {
683         return 0;
684 }
685 
686 static inline int bioset_integrity_create(struct bio_set *bs, int pool_size)
687 {
688         return 0;
689 }
690 
691 static inline void bioset_integrity_free (struct bio_set *bs)
692 {
693         return;
694 }
695 
696 static inline int bio_integrity_prep(struct bio *bio)
697 {
698         return 0;
699 }
700 
701 static inline void bio_integrity_free(struct bio *bio)
702 {
703         return;
704 }
705 
706 static inline int bio_integrity_clone(struct bio *bio, struct bio *bio_src,
707                                       gfp_t gfp_mask)
708 {
709         return 0;
710 }
711 
712 static inline void bio_integrity_advance(struct bio *bio,
713                                          unsigned int bytes_done)
714 {
715         return;
716 }
717 
718 static inline void bio_integrity_trim(struct bio *bio, unsigned int offset,
719                                       unsigned int sectors)
720 {
721         return;
722 }
723 
724 static inline void bio_integrity_init(void)
725 {
726         return;
727 }
728 
729 #endif /* CONFIG_BLK_DEV_INTEGRITY */
730 
731 #endif /* CONFIG_BLOCK */
732 #endif /* __LINUX_BIO_H */
733 

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