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