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 */ 105static 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 115static 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 126static 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 134static 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 142static 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/* 190 * Check if adding a bio_vec after bprv with offset would create a gap in 191 * the SG list. Most drivers don't care about this, but some do. 192 */ 193static inline bool bvec_gap_to_prev(struct bio_vec *bprv, unsigned int offset) 194{ 195 return offset || ((bprv->bv_offset + bprv->bv_len) & (PAGE_SIZE - 1)); 196} 197 198#define bio_io_error(bio) bio_endio((bio), -EIO) 199 200/* 201 * drivers should _never_ use the all version - the bio may have been split 202 * before it got to the driver and the driver won't own all of it 203 */ 204#define bio_for_each_segment_all(bvl, bio, i) \ 205 for (i = 0, bvl = (bio)->bi_io_vec; i < (bio)->bi_vcnt; i++, bvl++) 206 207static inline void bvec_iter_advance(struct bio_vec *bv, struct bvec_iter *iter, 208 unsigned bytes) 209{ 210 WARN_ONCE(bytes > iter->bi_size, 211 "Attempted to advance past end of bvec iter\n"); 212 213 while (bytes) { 214 unsigned len = min(bytes, bvec_iter_len(bv, *iter)); 215 216 bytes -= len; 217 iter->bi_size -= len; 218 iter->bi_bvec_done += len; 219 220 if (iter->bi_bvec_done == __bvec_iter_bvec(bv, *iter)->bv_len) { 221 iter->bi_bvec_done = 0; 222 iter->bi_idx++; 223 } 224 } 225} 226 227#define for_each_bvec(bvl, bio_vec, iter, start) \ 228 for (iter = (start); \ 229 (iter).bi_size && \ 230 ((bvl = bvec_iter_bvec((bio_vec), (iter))), 1); \ 231 bvec_iter_advance((bio_vec), &(iter), (bvl).bv_len)) 232 233 234static inline void bio_advance_iter(struct bio *bio, struct bvec_iter *iter, 235 unsigned bytes) 236{ 237 iter->bi_sector += bytes >> 9; 238 239 if (bio->bi_rw & BIO_NO_ADVANCE_ITER_MASK) 240 iter->bi_size -= bytes; 241 else 242 bvec_iter_advance(bio->bi_io_vec, iter, bytes); 243} 244 245#define __bio_for_each_segment(bvl, bio, iter, start) \ 246 for (iter = (start); \ 247 (iter).bi_size && \ 248 ((bvl = bio_iter_iovec((bio), (iter))), 1); \ 249 bio_advance_iter((bio), &(iter), (bvl).bv_len)) 250 251#define bio_for_each_segment(bvl, bio, iter) \ 252 __bio_for_each_segment(bvl, bio, iter, (bio)->bi_iter) 253 254#define bio_iter_last(bvec, iter) ((iter).bi_size == (bvec).bv_len) 255 256static inline unsigned bio_segments(struct bio *bio) 257{ 258 unsigned segs = 0; 259 struct bio_vec bv; 260 struct bvec_iter iter; 261 262 /* 263 * We special case discard/write same, because they interpret bi_size 264 * differently: 265 */ 266 267 if (bio->bi_rw & REQ_DISCARD) 268 return 1; 269 270 if (bio->bi_rw & REQ_WRITE_SAME) 271 return 1; 272 273 bio_for_each_segment(bv, bio, iter) 274 segs++; 275 276 return segs; 277} 278 279/* 280 * get a reference to a bio, so it won't disappear. the intended use is 281 * something like: 282 * 283 * bio_get(bio); 284 * submit_bio(rw, bio); 285 * if (bio->bi_flags ...) 286 * do_something 287 * bio_put(bio); 288 * 289 * without the bio_get(), it could potentially complete I/O before submit_bio 290 * returns. and then bio would be freed memory when if (bio->bi_flags ...) 291 * runs 292 */ 293#define bio_get(bio) atomic_inc(&(bio)->bi_cnt) 294 295enum bip_flags { 296 BIP_BLOCK_INTEGRITY = 1 << 0, /* block layer owns integrity data */ 297 BIP_MAPPED_INTEGRITY = 1 << 1, /* ref tag has been remapped */ 298 BIP_CTRL_NOCHECK = 1 << 2, /* disable HBA integrity checking */ 299 BIP_DISK_NOCHECK = 1 << 3, /* disable disk integrity checking */ 300 BIP_IP_CHECKSUM = 1 << 4, /* IP checksum */ 301}; 302 303#if defined(CONFIG_BLK_DEV_INTEGRITY) 304 305static inline struct bio_integrity_payload *bio_integrity(struct bio *bio) 306{ 307 if (bio->bi_rw & REQ_INTEGRITY) 308 return bio->bi_integrity; 309 310 return NULL; 311} 312 313/* 314 * bio integrity payload 315 */ 316struct bio_integrity_payload { 317 struct bio *bip_bio; /* parent bio */ 318 319 struct bvec_iter bip_iter; 320 321 bio_end_io_t *bip_end_io; /* saved I/O completion fn */ 322 323 unsigned short bip_slab; /* slab the bip came from */ 324 unsigned short bip_vcnt; /* # of integrity bio_vecs */ 325 unsigned short bip_max_vcnt; /* integrity bio_vec slots */ 326 unsigned short bip_flags; /* control flags */ 327 328 struct work_struct bip_work; /* I/O completion */ 329 330 struct bio_vec *bip_vec; 331 struct bio_vec bip_inline_vecs[0];/* embedded bvec array */ 332}; 333 334static inline bool bio_integrity_flagged(struct bio *bio, enum bip_flags flag) 335{ 336 struct bio_integrity_payload *bip = bio_integrity(bio); 337 338 if (bip) 339 return bip->bip_flags & flag; 340 341 return false; 342} 343 344static inline sector_t bip_get_seed(struct bio_integrity_payload *bip) 345{ 346 return bip->bip_iter.bi_sector; 347} 348 349static inline void bip_set_seed(struct bio_integrity_payload *bip, 350 sector_t seed) 351{ 352 bip->bip_iter.bi_sector = seed; 353} 354 355#endif /* CONFIG_BLK_DEV_INTEGRITY */ 356 357extern void bio_trim(struct bio *bio, int offset, int size); 358extern struct bio *bio_split(struct bio *bio, int sectors, 359 gfp_t gfp, struct bio_set *bs); 360 361/** 362 * bio_next_split - get next @sectors from a bio, splitting if necessary 363 * @bio: bio to split 364 * @sectors: number of sectors to split from the front of @bio 365 * @gfp: gfp mask 366 * @bs: bio set to allocate from 367 * 368 * Returns a bio representing the next @sectors of @bio - if the bio is smaller 369 * than @sectors, returns the original bio unchanged. 370 */ 371static inline struct bio *bio_next_split(struct bio *bio, int sectors, 372 gfp_t gfp, struct bio_set *bs) 373{ 374 if (sectors >= bio_sectors(bio)) 375 return bio; 376 377 return bio_split(bio, sectors, gfp, bs); 378} 379 380extern struct bio_set *bioset_create(unsigned int, unsigned int); 381extern struct bio_set *bioset_create_nobvec(unsigned int, unsigned int); 382extern void bioset_free(struct bio_set *); 383extern mempool_t *biovec_create_pool(int pool_entries); 384 385extern struct bio *bio_alloc_bioset(gfp_t, int, struct bio_set *); 386extern void bio_put(struct bio *); 387 388extern void __bio_clone_fast(struct bio *, struct bio *); 389extern struct bio *bio_clone_fast(struct bio *, gfp_t, struct bio_set *); 390extern struct bio *bio_clone_bioset(struct bio *, gfp_t, struct bio_set *bs); 391 392extern struct bio_set *fs_bio_set; 393 394static inline struct bio *bio_alloc(gfp_t gfp_mask, unsigned int nr_iovecs) 395{ 396 return bio_alloc_bioset(gfp_mask, nr_iovecs, fs_bio_set); 397} 398 399static inline struct bio *bio_clone(struct bio *bio, gfp_t gfp_mask) 400{ 401 return bio_clone_bioset(bio, gfp_mask, fs_bio_set); 402} 403 404static inline struct bio *bio_kmalloc(gfp_t gfp_mask, unsigned int nr_iovecs) 405{ 406 return bio_alloc_bioset(gfp_mask, nr_iovecs, NULL); 407} 408 409static inline struct bio *bio_clone_kmalloc(struct bio *bio, gfp_t gfp_mask) 410{ 411 return bio_clone_bioset(bio, gfp_mask, NULL); 412 413} 414 415extern void bio_endio(struct bio *, int); 416extern void bio_endio_nodec(struct bio *, int); 417struct request_queue; 418extern int bio_phys_segments(struct request_queue *, struct bio *); 419 420extern int submit_bio_wait(int rw, struct bio *bio); 421extern void bio_advance(struct bio *, unsigned); 422 423extern void bio_init(struct bio *); 424extern void bio_reset(struct bio *); 425void bio_chain(struct bio *, struct bio *); 426 427extern int bio_add_page(struct bio *, struct page *, unsigned int,unsigned int); 428extern int bio_add_pc_page(struct request_queue *, struct bio *, struct page *, 429 unsigned int, unsigned int); 430extern int bio_get_nr_vecs(struct block_device *); 431struct rq_map_data; 432extern struct bio *bio_map_user_iov(struct request_queue *, 433 const struct iov_iter *, gfp_t); 434extern void bio_unmap_user(struct bio *); 435extern struct bio *bio_map_kern(struct request_queue *, void *, unsigned int, 436 gfp_t); 437extern struct bio *bio_copy_kern(struct request_queue *, void *, unsigned int, 438 gfp_t, int); 439extern void bio_set_pages_dirty(struct bio *bio); 440extern void bio_check_pages_dirty(struct bio *bio); 441 442void generic_start_io_acct(int rw, unsigned long sectors, 443 struct hd_struct *part); 444void generic_end_io_acct(int rw, struct hd_struct *part, 445 unsigned long start_time); 446 447#ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 448# error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform" 449#endif 450#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 451extern void bio_flush_dcache_pages(struct bio *bi); 452#else 453static inline void bio_flush_dcache_pages(struct bio *bi) 454{ 455} 456#endif 457 458extern void bio_copy_data(struct bio *dst, struct bio *src); 459extern int bio_alloc_pages(struct bio *bio, gfp_t gfp); 460 461extern struct bio *bio_copy_user_iov(struct request_queue *, 462 struct rq_map_data *, 463 const struct iov_iter *, 464 gfp_t); 465extern int bio_uncopy_user(struct bio *); 466void zero_fill_bio(struct bio *bio); 467extern struct bio_vec *bvec_alloc(gfp_t, int, unsigned long *, mempool_t *); 468extern void bvec_free(mempool_t *, struct bio_vec *, unsigned int); 469extern unsigned int bvec_nr_vecs(unsigned short idx); 470 471#ifdef CONFIG_BLK_CGROUP 472int bio_associate_current(struct bio *bio); 473void bio_disassociate_task(struct bio *bio); 474#else /* CONFIG_BLK_CGROUP */ 475static inline int bio_associate_current(struct bio *bio) { return -ENOENT; } 476static inline void bio_disassociate_task(struct bio *bio) { } 477#endif /* CONFIG_BLK_CGROUP */ 478 479#ifdef CONFIG_HIGHMEM 480/* 481 * remember never ever reenable interrupts between a bvec_kmap_irq and 482 * bvec_kunmap_irq! 483 */ 484static inline char *bvec_kmap_irq(struct bio_vec *bvec, unsigned long *flags) 485{ 486 unsigned long addr; 487 488 /* 489 * might not be a highmem page, but the preempt/irq count 490 * balancing is a lot nicer this way 491 */ 492 local_irq_save(*flags); 493 addr = (unsigned long) kmap_atomic(bvec->bv_page); 494 495 BUG_ON(addr & ~PAGE_MASK); 496 497 return (char *) addr + bvec->bv_offset; 498} 499 500static inline void bvec_kunmap_irq(char *buffer, unsigned long *flags) 501{ 502 unsigned long ptr = (unsigned long) buffer & PAGE_MASK; 503 504 kunmap_atomic((void *) ptr); 505 local_irq_restore(*flags); 506} 507 508#else 509static inline char *bvec_kmap_irq(struct bio_vec *bvec, unsigned long *flags) 510{ 511 return page_address(bvec->bv_page) + bvec->bv_offset; 512} 513 514static inline void bvec_kunmap_irq(char *buffer, unsigned long *flags) 515{ 516 *flags = 0; 517} 518#endif 519 520static inline char *__bio_kmap_irq(struct bio *bio, struct bvec_iter iter, 521 unsigned long *flags) 522{ 523 return bvec_kmap_irq(&bio_iter_iovec(bio, iter), flags); 524} 525#define __bio_kunmap_irq(buf, flags) bvec_kunmap_irq(buf, flags) 526 527#define bio_kmap_irq(bio, flags) \ 528 __bio_kmap_irq((bio), (bio)->bi_iter, (flags)) 529#define bio_kunmap_irq(buf,flags) __bio_kunmap_irq(buf, flags) 530 531/* 532 * BIO list management for use by remapping drivers (e.g. DM or MD) and loop. 533 * 534 * A bio_list anchors a singly-linked list of bios chained through the bi_next 535 * member of the bio. The bio_list also caches the last list member to allow 536 * fast access to the tail. 537 */ 538struct bio_list { 539 struct bio *head; 540 struct bio *tail; 541}; 542 543static inline int bio_list_empty(const struct bio_list *bl) 544{ 545 return bl->head == NULL; 546} 547 548static inline void bio_list_init(struct bio_list *bl) 549{ 550 bl->head = bl->tail = NULL; 551} 552 553#define BIO_EMPTY_LIST { NULL, NULL } 554 555#define bio_list_for_each(bio, bl) \ 556 for (bio = (bl)->head; bio; bio = bio->bi_next) 557 558static inline unsigned bio_list_size(const struct bio_list *bl) 559{ 560 unsigned sz = 0; 561 struct bio *bio; 562 563 bio_list_for_each(bio, bl) 564 sz++; 565 566 return sz; 567} 568 569static inline void bio_list_add(struct bio_list *bl, struct bio *bio) 570{ 571 bio->bi_next = NULL; 572 573 if (bl->tail) 574 bl->tail->bi_next = bio; 575 else 576 bl->head = bio; 577 578 bl->tail = bio; 579} 580 581static inline void bio_list_add_head(struct bio_list *bl, struct bio *bio) 582{ 583 bio->bi_next = bl->head; 584 585 bl->head = bio; 586 587 if (!bl->tail) 588 bl->tail = bio; 589} 590 591static inline void bio_list_merge(struct bio_list *bl, struct bio_list *bl2) 592{ 593 if (!bl2->head) 594 return; 595 596 if (bl->tail) 597 bl->tail->bi_next = bl2->head; 598 else 599 bl->head = bl2->head; 600 601 bl->tail = bl2->tail; 602} 603 604static inline void bio_list_merge_head(struct bio_list *bl, 605 struct bio_list *bl2) 606{ 607 if (!bl2->head) 608 return; 609 610 if (bl->head) 611 bl2->tail->bi_next = bl->head; 612 else 613 bl->tail = bl2->tail; 614 615 bl->head = bl2->head; 616} 617 618static inline struct bio *bio_list_peek(struct bio_list *bl) 619{ 620 return bl->head; 621} 622 623static inline struct bio *bio_list_pop(struct bio_list *bl) 624{ 625 struct bio *bio = bl->head; 626 627 if (bio) { 628 bl->head = bl->head->bi_next; 629 if (!bl->head) 630 bl->tail = NULL; 631 632 bio->bi_next = NULL; 633 } 634 635 return bio; 636} 637 638static inline struct bio *bio_list_get(struct bio_list *bl) 639{ 640 struct bio *bio = bl->head; 641 642 bl->head = bl->tail = NULL; 643 644 return bio; 645} 646 647/* 648 * bio_set is used to allow other portions of the IO system to 649 * allocate their own private memory pools for bio and iovec structures. 650 * These memory pools in turn all allocate from the bio_slab 651 * and the bvec_slabs[]. 652 */ 653#define BIO_POOL_SIZE 2 654#define BIOVEC_NR_POOLS 6 655#define BIOVEC_MAX_IDX (BIOVEC_NR_POOLS - 1) 656 657struct bio_set { 658 struct kmem_cache *bio_slab; 659 unsigned int front_pad; 660 661 mempool_t *bio_pool; 662 mempool_t *bvec_pool; 663#if defined(CONFIG_BLK_DEV_INTEGRITY) 664 mempool_t *bio_integrity_pool; 665 mempool_t *bvec_integrity_pool; 666#endif 667 668 /* 669 * Deadlock avoidance for stacking block drivers: see comments in 670 * bio_alloc_bioset() for details 671 */ 672 spinlock_t rescue_lock; 673 struct bio_list rescue_list; 674 struct work_struct rescue_work; 675 struct workqueue_struct *rescue_workqueue; 676}; 677 678struct biovec_slab { 679 int nr_vecs; 680 char *name; 681 struct kmem_cache *slab; 682}; 683 684/* 685 * a small number of entries is fine, not going to be performance critical. 686 * basically we just need to survive 687 */ 688#define BIO_SPLIT_ENTRIES 2 689 690#if defined(CONFIG_BLK_DEV_INTEGRITY) 691 692#define bip_for_each_vec(bvl, bip, iter) \ 693 for_each_bvec(bvl, (bip)->bip_vec, iter, (bip)->bip_iter) 694 695#define bio_for_each_integrity_vec(_bvl, _bio, _iter) \ 696 for_each_bio(_bio) \ 697 bip_for_each_vec(_bvl, _bio->bi_integrity, _iter) 698 699extern struct bio_integrity_payload *bio_integrity_alloc(struct bio *, gfp_t, unsigned int); 700extern void bio_integrity_free(struct bio *); 701extern int bio_integrity_add_page(struct bio *, struct page *, unsigned int, unsigned int); 702extern bool bio_integrity_enabled(struct bio *bio); 703extern int bio_integrity_prep(struct bio *); 704extern void bio_integrity_endio(struct bio *, int); 705extern void bio_integrity_advance(struct bio *, unsigned int); 706extern void bio_integrity_trim(struct bio *, unsigned int, unsigned int); 707extern int bio_integrity_clone(struct bio *, struct bio *, gfp_t); 708extern int bioset_integrity_create(struct bio_set *, int); 709extern void bioset_integrity_free(struct bio_set *); 710extern void bio_integrity_init(void); 711 712#else /* CONFIG_BLK_DEV_INTEGRITY */ 713 714static inline void *bio_integrity(struct bio *bio) 715{ 716 return NULL; 717} 718 719static inline bool bio_integrity_enabled(struct bio *bio) 720{ 721 return false; 722} 723 724static inline int bioset_integrity_create(struct bio_set *bs, int pool_size) 725{ 726 return 0; 727} 728 729static inline void bioset_integrity_free (struct bio_set *bs) 730{ 731 return; 732} 733 734static inline int bio_integrity_prep(struct bio *bio) 735{ 736 return 0; 737} 738 739static inline void bio_integrity_free(struct bio *bio) 740{ 741 return; 742} 743 744static inline int bio_integrity_clone(struct bio *bio, struct bio *bio_src, 745 gfp_t gfp_mask) 746{ 747 return 0; 748} 749 750static inline void bio_integrity_advance(struct bio *bio, 751 unsigned int bytes_done) 752{ 753 return; 754} 755 756static inline void bio_integrity_trim(struct bio *bio, unsigned int offset, 757 unsigned int sectors) 758{ 759 return; 760} 761 762static inline void bio_integrity_init(void) 763{ 764 return; 765} 766 767static inline bool bio_integrity_flagged(struct bio *bio, enum bip_flags flag) 768{ 769 return false; 770} 771 772#endif /* CONFIG_BLK_DEV_INTEGRITY */ 773 774#endif /* CONFIG_BLOCK */ 775#endif /* __LINUX_BIO_H */ 776