include/linux/bio.h

   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 bio_iovec_idx(bio, idx) (&((bio)->bi_io_vec[(idx)]))
  65 #define bio_iovec(bio)          bio_iovec_idx((bio), (bio)->bi_idx)
  66 #define bio_page(bio)           bio_iovec((bio))->bv_page
  67 #define bio_offset(bio)         bio_iovec((bio))->bv_offset
  68 #define bio_segments(bio)       ((bio)->bi_vcnt - (bio)->bi_idx)
  69 #define bio_sectors(bio)        ((bio)->bi_size >> 9)
  70 #define bio_end_sector(bio)     ((bio)->bi_sector + bio_sectors((bio)))
  71
  72 static inline unsigned int bio_cur_bytes(struct bio *bio)
  73 {
  74         if (bio->bi_vcnt)
  75                 return bio_iovec(bio)->bv_len;
  76         else /* dataless requests such as discard */
  77                 return bio->bi_size;
  78 }
  79
  80 static inline void *bio_data(struct bio *bio)
  81 {
  82         if (bio->bi_vcnt)
  83                 return page_address(bio_page(bio)) + bio_offset(bio);
  84
  85         return NULL;
  86 }
  87
  88 /*
  89  * will die
  90  */
  91 #define bio_to_phys(bio)        (page_to_phys(bio_page((bio))) + (unsigned long) bio_offset((bio)))
  92 #define bvec_to_phys(bv)        (page_to_phys((bv)->bv_page) + (unsigned long) (bv)->bv_offset)
  93
  94 /*
  95  * queues that have highmem support enabled may still need to revert to
  96  * PIO transfers occasionally and thus map high pages temporarily. For
  97  * permanent PIO fall back, user is probably better off disabling highmem
  98  * I/O completely on that queue (see ide-dma for example)
  99  */
 100 #define __bio_kmap_atomic(bio, idx, kmtype)                             \
 101         (kmap_atomic(bio_iovec_idx((bio), (idx))->bv_page) +    \
 102                 bio_iovec_idx((bio), (idx))->bv_offset)
 103
 104 #define __bio_kunmap_atomic(addr, kmtype) kunmap_atomic(addr)
 105
 106 /*
 107  * merge helpers etc
 108  */
 109
 110 #define __BVEC_END(bio)         bio_iovec_idx((bio), (bio)->bi_vcnt - 1)
 111 #define __BVEC_START(bio)       bio_iovec_idx((bio), (bio)->bi_idx)
 112
 113 /* Default implementation of BIOVEC_PHYS_MERGEABLE */
 114 #define __BIOVEC_PHYS_MERGEABLE(vec1, vec2)     \
 115         ((bvec_to_phys((vec1)) + (vec1)->bv_len) == bvec_to_phys((vec2)))
 116
 117 /*
 118  * allow arch override, for eg virtualized architectures (put in asm/io.h)
 119  */
 120 #ifndef BIOVEC_PHYS_MERGEABLE
 121 #define BIOVEC_PHYS_MERGEABLE(vec1, vec2)       \
 122         __BIOVEC_PHYS_MERGEABLE(vec1, vec2)
 123 #endif
 124
 125 #define __BIO_SEG_BOUNDARY(addr1, addr2, mask) \
 126         (((addr1) | (mask)) == (((addr2) - 1) | (mask)))
 127 #define BIOVEC_SEG_BOUNDARY(q, b1, b2) \
 128         __BIO_SEG_BOUNDARY(bvec_to_phys((b1)), bvec_to_phys((b2)) + (b2)->bv_len, queue_segment_boundary((q)))
 129 #define BIO_SEG_BOUNDARY(q, b1, b2) \
 130         BIOVEC_SEG_BOUNDARY((q), __BVEC_END((b1)), __BVEC_START((b2)))
 131
 132 #define bio_io_error(bio) bio_endio((bio), -EIO)
 133
 134 /*
 135  * drivers should not use the __ version unless they _really_ know what
 136  * they're doing
 137  */
 138 #define __bio_for_each_segment(bvl, bio, i, start_idx)                  \
 139         for (bvl = bio_iovec_idx((bio), (start_idx)), i = (start_idx);  \
 140              i < (bio)->bi_vcnt;                                        \
 141              bvl++, i++)
 142
 143 /*
 144  * drivers should _never_ use the all version - the bio may have been split
 145  * before it got to the driver and the driver won't own all of it
 146  */
 147 #define bio_for_each_segment_all(bvl, bio, i)                           \
 148         for (i = 0;                                                     \
 149              bvl = bio_iovec_idx((bio), (i)), i < (bio)->bi_vcnt;       \
 150              i++)
 151
 152 #define bio_for_each_segment(bvl, bio, i)                               \
 153         for (i = (bio)->bi_idx;                                         \
 154              bvl = bio_iovec_idx((bio), (i)), i < (bio)->bi_vcnt;       \
 155              i++)
 156
 157 /*
 158  * get a reference to a bio, so it won't disappear. the intended use is
 159  * something like:
 160  *
 161  * bio_get(bio);
 162  * submit_bio(rw, bio);
 163  * if (bio->bi_flags ...)
 164  *      do_something
 165  * bio_put(bio);
 166  *
 167  * without the bio_get(), it could potentially complete I/O before submit_bio
 168  * returns. and then bio would be freed memory when if (bio->bi_flags ...)
 169  * runs
 170  */
 171 #define bio_get(bio)    atomic_inc(&(bio)->bi_cnt)
 172
 173 #if defined(CONFIG_BLK_DEV_INTEGRITY)
 174 /*
 175  * bio integrity payload
 176  */
 177 struct bio_integrity_payload {
 178         struct bio              *bip_bio;       /* parent bio */
 179
 180         sector_t                bip_sector;     /* virtual start sector */
 181
 182         void                    *bip_buf;       /* generated integrity data */
 183         bio_end_io_t            *bip_end_io;    /* saved I/O completion fn */
 184
 185         unsigned int            bip_size;
 186
 187         unsigned short          bip_slab;       /* slab the bip came from */
 188         unsigned short          bip_vcnt;       /* # of integrity bio_vecs */
 189         unsigned short          bip_idx;        /* current bip_vec index */
 190
 191         struct work_struct      bip_work;       /* I/O completion */
 192
 193         struct bio_vec          *bip_vec;
 194         struct bio_vec          bip_inline_vecs[0];/* embedded bvec array */
 195 };
 196 #endif /* CONFIG_BLK_DEV_INTEGRITY */
 197
 198 /*
 199  * A bio_pair is used when we need to split a bio.
 200  * This can only happen for a bio that refers to just one
 201  * page of data, and in the unusual situation when the
 202  * page crosses a chunk/device boundary
 203  *
 204  * The address of the master bio is stored in bio1.bi_private
 205  * The address of the pool the pair was allocated from is stored
 206  *   in bio2.bi_private
 207  */
 208 struct bio_pair {
 209         struct bio                      bio1, bio2;
 210         struct bio_vec                  bv1, bv2;
 211 #if defined(CONFIG_BLK_DEV_INTEGRITY)
 212         struct bio_integrity_payload    bip1, bip2;
 213         struct bio_vec                  iv1, iv2;
 214 #endif
 215         atomic_t                        cnt;
 216         int                             error;
 217 };
 218 extern struct bio_pair *bio_split(struct bio *bi, int first_sectors);
 219 extern void bio_pair_release(struct bio_pair *dbio);
 220
 221 extern struct bio_set *bioset_create(unsigned int, unsigned int);
 222 extern void bioset_free(struct bio_set *);
 223 extern mempool_t *biovec_create_pool(struct bio_set *bs, int pool_entries);
 224
 225 extern struct bio *bio_alloc_bioset(gfp_t, int, struct bio_set *);
 226 extern void bio_put(struct bio *);
 227
 228 extern void __bio_clone(struct bio *, struct bio *);
 229 extern struct bio *bio_clone_bioset(struct bio *, gfp_t, struct bio_set *bs);
 230
 231 extern struct bio_set *fs_bio_set;
 232
 233 static inline struct bio *bio_alloc(gfp_t gfp_mask, unsigned int nr_iovecs)
 234 {
 235         return bio_alloc_bioset(gfp_mask, nr_iovecs, fs_bio_set);
 236 }
 237
 238 static inline struct bio *bio_clone(struct bio *bio, gfp_t gfp_mask)
 239 {
 240         return bio_clone_bioset(bio, gfp_mask, fs_bio_set);
 241 }
 242
 243 static inline struct bio *bio_kmalloc(gfp_t gfp_mask, unsigned int nr_iovecs)
 244 {
 245         return bio_alloc_bioset(gfp_mask, nr_iovecs, NULL);
 246 }
 247
 248 static inline struct bio *bio_clone_kmalloc(struct bio *bio, gfp_t gfp_mask)
 249 {
 250         return bio_clone_bioset(bio, gfp_mask, NULL);
 251
 252 }
 253
 254 extern void bio_endio(struct bio *, int);
 255 struct request_queue;
 256 extern int bio_phys_segments(struct request_queue *, struct bio *);
 257
 258 extern int submit_bio_wait(int rw, struct bio *bio);
 259 extern void bio_advance(struct bio *, unsigned);
 260
 261 extern void bio_init(struct bio *);
 262 extern void bio_reset(struct bio *);
 263
 264 extern int bio_add_page(struct bio *, struct page *, unsigned int,unsigned int);
 265 extern int bio_add_pc_page(struct request_queue *, struct bio *, struct page *,
 266                            unsigned int, unsigned int);
 267 extern int bio_get_nr_vecs(struct block_device *);
 268 extern sector_t bio_sector_offset(struct bio *, unsigned short, unsigned int);
 269 extern struct bio *bio_map_user(struct request_queue *, struct block_device *,
 270                                 unsigned long, unsigned int, int, gfp_t);
 271 struct sg_iovec;
 272 struct rq_map_data;
 273 extern struct bio *bio_map_user_iov(struct request_queue *,
 274                                     struct block_device *,
 275                                     struct sg_iovec *, int, int, gfp_t);
 276 extern void bio_unmap_user(struct bio *);
 277 extern struct bio *bio_map_kern(struct request_queue *, void *, unsigned int,
 278                                 gfp_t);
 279 extern struct bio *bio_copy_kern(struct request_queue *, void *, unsigned int,
 280                                  gfp_t, int);
 281 extern void bio_set_pages_dirty(struct bio *bio);
 282 extern void bio_check_pages_dirty(struct bio *bio);
 283
 284 #ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
 285 # error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform"
 286 #endif
 287 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
 288 extern void bio_flush_dcache_pages(struct bio *bi);
 289 #else
 290 static inline void bio_flush_dcache_pages(struct bio *bi)
 291 {
 292 }
 293 #endif
 294
 295 extern void bio_copy_data(struct bio *dst, struct bio *src);
 296 extern int bio_alloc_pages(struct bio *bio, gfp_t gfp);
 297
 298 extern struct bio *bio_copy_user(struct request_queue *, struct rq_map_data *,
 299                                  unsigned long, unsigned int, int, gfp_t);
 300 extern struct bio *bio_copy_user_iov(struct request_queue *,
 301                                      struct rq_map_data *, struct sg_iovec *,
 302                                      int, int, gfp_t);
 303 extern int bio_uncopy_user(struct bio *);
 304 void zero_fill_bio(struct bio *bio);
 305 extern struct bio_vec *bvec_alloc(gfp_t, int, unsigned long *, mempool_t *);
 306 extern void bvec_free(mempool_t *, struct bio_vec *, unsigned int);
 307 extern unsigned int bvec_nr_vecs(unsigned short idx);
 308
 309 #ifdef CONFIG_BLK_CGROUP
 310 int bio_associate_current(struct bio *bio);
 311 void bio_disassociate_task(struct bio *bio);
 312 #else   /* CONFIG_BLK_CGROUP */
 313 static inline int bio_associate_current(struct bio *bio) { return -ENOENT; }
 314 static inline void bio_disassociate_task(struct bio *bio) { }
 315 #endif  /* CONFIG_BLK_CGROUP */
 316
 317 #ifdef CONFIG_HIGHMEM
 318 /*
 319  * remember never ever reenable interrupts between a bvec_kmap_irq and
 320  * bvec_kunmap_irq!
 321  */
 322 static inline char *bvec_kmap_irq(struct bio_vec *bvec, unsigned long *flags)
 323 {
 324         unsigned long addr;
 325
 326         /*
 327          * might not be a highmem page, but the preempt/irq count
 328          * balancing is a lot nicer this way
 329          */
 330         local_irq_save(*flags);
 331         addr = (unsigned long) kmap_atomic(bvec->bv_page);
 332
 333         BUG_ON(addr & ~PAGE_MASK);
 334
 335         return (char *) addr + bvec->bv_offset;
 336 }
 337
 338 static inline void bvec_kunmap_irq(char *buffer, unsigned long *flags)
 339 {
 340         unsigned long ptr = (unsigned long) buffer & PAGE_MASK;
 341
 342         kunmap_atomic((void *) ptr);
 343         local_irq_restore(*flags);
 344 }
 345
 346 #else
 347 static inline char *bvec_kmap_irq(struct bio_vec *bvec, unsigned long *flags)
 348 {
 349         return page_address(bvec->bv_page) + bvec->bv_offset;
 350 }
 351
 352 static inline void bvec_kunmap_irq(char *buffer, unsigned long *flags)
 353 {
 354         *flags = 0;
 355 }
 356 #endif
 357
 358 static inline char *__bio_kmap_irq(struct bio *bio, unsigned short idx,
 359                                    unsigned long *flags)
 360 {
 361         return bvec_kmap_irq(bio_iovec_idx(bio, idx), flags);
 362 }
 363 #define __bio_kunmap_irq(buf, flags)    bvec_kunmap_irq(buf, flags)
 364
 365 #define bio_kmap_irq(bio, flags) \
 366         __bio_kmap_irq((bio), (bio)->bi_idx, (flags))
 367 #define bio_kunmap_irq(buf,flags)       __bio_kunmap_irq(buf, flags)
 368
 369 /*
 370  * Check whether this bio carries any data or not. A NULL bio is allowed.
 371  */
 372 static inline bool bio_has_data(struct bio *bio)
 373 {
 374         if (bio && bio->bi_vcnt)
 375                 return true;
 376
 377         return false;
 378 }
 379
 380 static inline bool bio_is_rw(struct bio *bio)
 381 {
 382         if (!bio_has_data(bio))
 383                 return false;
 384
 385         if (bio->bi_rw & REQ_WRITE_SAME)
 386                 return false;
 387
 388         return true;
 389 }
 390
 391 static inline bool bio_mergeable(struct bio *bio)
 392 {
 393         if (bio->bi_rw & REQ_NOMERGE_FLAGS)
 394                 return false;
 395
 396         return true;
 397 }
 398
 399 /*
 400  * BIO list management for use by remapping drivers (e.g. DM or MD) and loop.
 401  *
 402  * A bio_list anchors a singly-linked list of bios chained through the bi_next
 403  * member of the bio.  The bio_list also caches the last list member to allow
 404  * fast access to the tail.
 405  */
 406 struct bio_list {
 407         struct bio *head;
 408         struct bio *tail;
 409 };
 410
 411 static inline int bio_list_empty(const struct bio_list *bl)
 412 {
 413         return bl->head == NULL;
 414 }
 415
 416 static inline void bio_list_init(struct bio_list *bl)
 417 {
 418         bl->head = bl->tail = NULL;
 419 }
 420
 421 #define bio_list_for_each(bio, bl) \
 422         for (bio = (bl)->head; bio; bio = bio->bi_next)
 423
 424 static inline unsigned bio_list_size(const struct bio_list *bl)
 425 {
 426         unsigned sz = 0;
 427         struct bio *bio;
 428
 429         bio_list_for_each(bio, bl)
 430                 sz++;
 431
 432         return sz;
 433 }
 434
 435 static inline void bio_list_add(struct bio_list *bl, struct bio *bio)
 436 {
 437         bio->bi_next = NULL;
 438
 439         if (bl->tail)
 440                 bl->tail->bi_next = bio;
 441         else
 442                 bl->head = bio;
 443
 444         bl->tail = bio;
 445 }
 446
 447 static inline void bio_list_add_head(struct bio_list *bl, struct bio *bio)
 448 {
 449         bio->bi_next = bl->head;
 450
 451         bl->head = bio;
 452
 453         if (!bl->tail)
 454                 bl->tail = bio;
 455 }
 456
 457 static inline void bio_list_merge(struct bio_list *bl, struct bio_list *bl2)
 458 {
 459         if (!bl2->head)
 460                 return;
 461
 462         if (bl->tail)
 463                 bl->tail->bi_next = bl2->head;
 464         else
 465                 bl->head = bl2->head;
 466
 467         bl->tail = bl2->tail;
 468 }
 469
 470 static inline void bio_list_merge_head(struct bio_list *bl,
 471                                        struct bio_list *bl2)
 472 {
 473         if (!bl2->head)
 474                 return;
 475
 476         if (bl->head)
 477                 bl2->tail->bi_next = bl->head;
 478         else
 479                 bl->tail = bl2->tail;
 480
 481         bl->head = bl2->head;
 482 }
 483
 484 static inline struct bio *bio_list_peek(struct bio_list *bl)
 485 {
 486         return bl->head;
 487 }
 488
 489 static inline struct bio *bio_list_pop(struct bio_list *bl)
 490 {
 491         struct bio *bio = bl->head;
 492
 493         if (bio) {
 494                 bl->head = bl->head->bi_next;
 495                 if (!bl->head)
 496                         bl->tail = NULL;
 497
 498                 bio->bi_next = NULL;
 499         }
 500
 501         return bio;
 502 }
 503
 504 static inline struct bio *bio_list_get(struct bio_list *bl)
 505 {
 506         struct bio *bio = bl->head;
 507
 508         bl->head = bl->tail = NULL;
 509
 510         return bio;
 511 }
 512
 513 /*
 514  * bio_set is used to allow other portions of the IO system to
 515  * allocate their own private memory pools for bio and iovec structures.
 516  * These memory pools in turn all allocate from the bio_slab
 517  * and the bvec_slabs[].
 518  */
 519 #define BIO_POOL_SIZE 2
 520 #define BIOVEC_NR_POOLS 6
 521 #define BIOVEC_MAX_IDX  (BIOVEC_NR_POOLS - 1)
 522
 523 struct bio_set {
 524         struct kmem_cache *bio_slab;
 525         unsigned int front_pad;
 526
 527         mempool_t *bio_pool;
 528         mempool_t *bvec_pool;
 529 #if defined(CONFIG_BLK_DEV_INTEGRITY)
 530         mempool_t *bio_integrity_pool;
 531         mempool_t *bvec_integrity_pool;
 532 #endif
 533
 534         /*
 535          * Deadlock avoidance for stacking block drivers: see comments in
 536          * bio_alloc_bioset() for details
 537          */
 538         spinlock_t              rescue_lock;
 539         struct bio_list         rescue_list;
 540         struct work_struct      rescue_work;
 541         struct workqueue_struct *rescue_workqueue;
 542 };
 543
 544 struct biovec_slab {
 545         int nr_vecs;
 546         char *name;
 547         struct kmem_cache *slab;
 548 };
 549
 550 /*
 551  * a small number of entries is fine, not going to be performance critical.
 552  * basically we just need to survive
 553  */
 554 #define BIO_SPLIT_ENTRIES 2
 555
 556 #if defined(CONFIG_BLK_DEV_INTEGRITY)
 557
 558 #define bip_vec_idx(bip, idx)   (&(bip->bip_vec[(idx)]))
 559 #define bip_vec(bip)            bip_vec_idx(bip, 0)
 560
 561 #define __bip_for_each_vec(bvl, bip, i, start_idx)                      \
 562         for (bvl = bip_vec_idx((bip), (start_idx)), i = (start_idx);    \
 563              i < (bip)->bip_vcnt;                                       \
 564              bvl++, i++)
 565
 566 #define bip_for_each_vec(bvl, bip, i)                                   \
 567         __bip_for_each_vec(bvl, bip, i, (bip)->bip_idx)
 568
 569 #define bio_for_each_integrity_vec(_bvl, _bio, _iter)                   \
 570         for_each_bio(_bio)                                              \
 571                 bip_for_each_vec(_bvl, _bio->bi_integrity, _iter)
 572
 573 #define bio_integrity(bio) (bio->bi_integrity != NULL)
 574
 575 extern struct bio_integrity_payload *bio_integrity_alloc(struct bio *, gfp_t, unsigned int);
 576 extern void bio_integrity_free(struct bio *);
 577 extern int bio_integrity_add_page(struct bio *, struct page *, unsigned int, unsigned int);
 578 extern int bio_integrity_enabled(struct bio *bio);
 579 extern int bio_integrity_set_tag(struct bio *, void *, unsigned int);
 580 extern int bio_integrity_get_tag(struct bio *, void *, unsigned int);
 581 extern int bio_integrity_prep(struct bio *);
 582 extern void bio_integrity_endio(struct bio *, int);
 583 extern void bio_integrity_advance(struct bio *, unsigned int);
 584 extern void bio_integrity_trim(struct bio *, unsigned int, unsigned int);
 585 extern void bio_integrity_split(struct bio *, struct bio_pair *, int);
 586 extern int bio_integrity_clone(struct bio *, struct bio *, gfp_t);
 587 extern int bioset_integrity_create(struct bio_set *, int);
 588 extern void bioset_integrity_free(struct bio_set *);
 589 extern void bio_integrity_init(void);
 590
 591 #else /* CONFIG_BLK_DEV_INTEGRITY */
 592
 593 static inline int bio_integrity(struct bio *bio)
 594 {
 595         return 0;
 596 }
 597
 598 static inline int bio_integrity_enabled(struct bio *bio)
 599 {
 600         return 0;
 601 }
 602
 603 static inline int bioset_integrity_create(struct bio_set *bs, int pool_size)
 604 {
 605         return 0;
 606 }
 607
 608 static inline void bioset_integrity_free (struct bio_set *bs)
 609 {
 610         return;
 611 }
 612
 613 static inline int bio_integrity_prep(struct bio *bio)
 614 {
 615         return 0;
 616 }
 617
 618 static inline void bio_integrity_free(struct bio *bio)
 619 {
 620         return;
 621 }
 622
 623 static inline int bio_integrity_clone(struct bio *bio, struct bio *bio_src,
 624                                       gfp_t gfp_mask)
 625 {
 626         return 0;
 627 }
 628
 629 static inline void bio_integrity_split(struct bio *bio, struct bio_pair *bp,
 630                                        int sectors)
 631 {
 632         return;
 633 }
 634
 635 static inline void bio_integrity_advance(struct bio *bio,
 636                                          unsigned int bytes_done)
 637 {
 638         return;
 639 }
 640
 641 static inline void bio_integrity_trim(struct bio *bio, unsigned int offset,
 642                                       unsigned int sectors)
 643 {
 644         return;
 645 }
 646
 647 static inline void bio_integrity_init(void)
 648 {
 649         return;
 650 }
 651
 652 #endif /* CONFIG_BLK_DEV_INTEGRITY */
 653
 654 #endif /* CONFIG_BLOCK */
 655 #endif /* __LINUX_BIO_H */