1 /* 2 * Copyright (C) 2001 Jens Axboe <axboe@suse.de> 3 * 4 * This program is free software; you can redistribute it and/or modify 5 * it under the terms of the GNU General Public License version 2 as 6 * published by the Free Software Foundation. 7 * 8 * This program is distributed in the hope that it will be useful, 9 * but WITHOUT ANY WARRANTY; without even the implied warranty of 10 * 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 12 * GNU General Public License for more details. 13 * 14 * You should have received a copy of the GNU General Public Licens 15 * along with this program; if not, write to the Free Software 16 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111- 17 */ 18 #ifndef __LINUX_BIO_H 19 #define __LINUX_BIO_H 20 21 #include <linux/highmem.h> 22 #include <linux/mempool.h> 23 #include <linux/ioprio.h> 24 #include <linux/bug.h> 25 26 #ifdef CONFIG_BLOCK 27 28 #include <asm/io.h> 29 30 /* struct bio, bio_vec and BIO_* flags are defined in blk_types.h */ 31 #include <linux/blk_types.h> 32 33 #define BIO_DEBUG 34 35 #ifdef BIO_DEBUG 36 #define BIO_BUG_ON BUG_ON 37 #else 38 #define BIO_BUG_ON 39 #endif 40 41 #ifdef CONFIG_THP_SWAP 42 #if HPAGE_PMD_NR > 256 43 #define BIO_MAX_PAGES HPAGE_PMD_NR 44 #else 45 #define BIO_MAX_PAGES 256 46 #endif 47 #else 48 #define BIO_MAX_PAGES 256 49 #endif 50 51 #define bio_prio(bio) (bio)->bi_ioprio 52 #define bio_set_prio(bio, prio) ((bio)->bi_ioprio = prio) 53 54 #define bio_iter_iovec(bio, iter) \ 55 bvec_iter_bvec((bio)->bi_io_vec, (iter)) 56 57 #define bio_iter_page(bio, iter) \ 58 bvec_iter_page((bio)->bi_io_vec, (iter)) 59 #define bio_iter_len(bio, iter) \ 60 bvec_iter_len((bio)->bi_io_vec, (iter)) 61 #define bio_iter_offset(bio, iter) \ 62 bvec_iter_offset((bio)->bi_io_vec, (iter)) 63 64 #define bio_page(bio) bio_iter_page((bio), (bio)->bi_iter) 65 #define bio_offset(bio) bio_iter_offset((bio), (bio)->bi_iter) 66 #define bio_iovec(bio) bio_iter_iovec((bio), (bio)->bi_iter) 67 68 #define bio_multiple_segments(bio) \ 69 ((bio)->bi_iter.bi_size != bio_iovec(bio).bv_len) 70 #define bio_sectors(bio) ((bio)->bi_iter.bi_size >> 9) 71 #define bio_end_sector(bio) ((bio)->bi_iter.bi_sector + bio_sectors((bio))) 72 73 /* 74 * Return the data direction, READ or WRITE. 75 */ 76 #define bio_data_dir(bio) \ 77 (op_is_write(bio_op(bio)) ? WRITE : READ) 78 79 /* 80 * Check whether this bio carries any data or not. A NULL bio is allowed. 81 */ 82 static inline bool bio_has_data(struct bio *bio) 83 { 84 if (bio && 85 bio->bi_iter.bi_size && 86 bio_op(bio) != REQ_OP_DISCARD && 87 bio_op(bio) != REQ_OP_SECURE_ERASE && 88 bio_op(bio) != REQ_OP_WRITE_ZEROES) 89 return true; 90 91 return false; 92 } 93 94 static inline bool bio_no_advance_iter(struct bio *bio) 95 { 96 return bio_op(bio) == REQ_OP_DISCARD || 97 bio_op(bio) == REQ_OP_SECURE_ERASE || 98 bio_op(bio) == REQ_OP_WRITE_SAME || 99 bio_op(bio) == REQ_OP_WRITE_ZEROES; 100 } 101 102 static inline bool bio_mergeable(struct bio *bio) 103 { 104 if (bio->bi_opf & REQ_NOMERGE_FLAGS) 105 return false; 106 107 return true; 108 } 109 110 static inline unsigned int bio_cur_bytes(struct bio *bio) 111 { 112 if (bio_has_data(bio)) 113 return bio_iovec(bio).bv_len; 114 else /* dataless requests such as discard */ 115 return bio->bi_iter.bi_size; 116 } 117 118 static inline void *bio_data(struct bio *bio) 119 { 120 if (bio_has_data(bio)) 121 return page_address(bio_page(bio)) + bio_offset(bio); 122 123 return NULL; 124 } 125 126 /* 127 * will die 128 */ 129 #define bvec_to_phys(bv) (page_to_phys((bv)->bv_page) + (unsigned long) (bv)->bv_offset) 130 131 /* 132 * merge helpers etc 133 */ 134 135 /* Default implementation of BIOVEC_PHYS_MERGEABLE */ 136 #define __BIOVEC_PHYS_MERGEABLE(vec1, vec2) \ 137 ((bvec_to_phys((vec1)) + (vec1)->bv_len) == bvec_to_phys((vec2))) 138 139 /* 140 * allow arch override, for eg virtualized architectures (put in asm/io.h) 141 */ 142 #ifndef BIOVEC_PHYS_MERGEABLE 143 #define BIOVEC_PHYS_MERGEABLE(vec1, vec2) \ 144 __BIOVEC_PHYS_MERGEABLE(vec1, vec2) 145 #endif 146 147 #define __BIO_SEG_BOUNDARY(addr1, addr2, mask) \ 148 (((addr1) | (mask)) == (((addr2) - 1) | (mask))) 149 #define BIOVEC_SEG_BOUNDARY(q, b1, b2) \ 150 __BIO_SEG_BOUNDARY(bvec_to_phys((b1)), bvec_to_phys((b2)) + (b2)->bv_len, queue_segment_boundary((q))) 151 152 /* 153 * drivers should _never_ use the all version - the bio may have been split 154 * before it got to the driver and the driver won't own all of it 155 */ 156 #define bio_for_each_segment_all(bvl, bio, i) \ 157 for (i = 0, bvl = (bio)->bi_io_vec; i < (bio)->bi_vcnt; i++, bvl++) 158 159 static inline void bio_advance_iter(struct bio *bio, struct bvec_iter *iter, 160 unsigned bytes) 161 { 162 iter->bi_sector += bytes >> 9; 163 164 if (bio_no_advance_iter(bio)) { 165 iter->bi_size -= bytes; 166 iter->bi_done += bytes; 167 } else { 168 bvec_iter_advance(bio->bi_io_vec, iter, bytes); 169 /* TODO: It is reasonable to complete bio with error here. */ 170 } 171 } 172 173 static inline bool bio_rewind_iter(struct bio *bio, struct bvec_iter *iter, 174 unsigned int bytes) 175 { 176 iter->bi_sector -= bytes >> 9; 177 178 if (bio_no_advance_iter(bio)) { 179 iter->bi_size += bytes; 180 iter->bi_done -= bytes; 181 return true; 182 } 183 184 return bvec_iter_rewind(bio->bi_io_vec, iter, bytes); 185 } 186 187 #define __bio_for_each_segment(bvl, bio, iter, start) \ 188 for (iter = (start); \ 189 (iter).bi_size && \ 190 ((bvl = bio_iter_iovec((bio), (iter))), 1); \ 191 bio_advance_iter((bio), &(iter), (bvl).bv_len)) 192 193 #define bio_for_each_segment(bvl, bio, iter) \ 194 __bio_for_each_segment(bvl, bio, iter, (bio)->bi_iter) 195 196 #define bio_iter_last(bvec, iter) ((iter).bi_size == (bvec).bv_len) 197 198 static inline unsigned bio_segments(struct bio *bio) 199 { 200 unsigned segs = 0; 201 struct bio_vec bv; 202 struct bvec_iter iter; 203 204 /* 205 * We special case discard/write same/write zeroes, because they 206 * interpret bi_size differently: 207 */ 208 209 switch (bio_op(bio)) { 210 case REQ_OP_DISCARD: 211 case REQ_OP_SECURE_ERASE: 212 case REQ_OP_WRITE_ZEROES: 213 return 0; 214 case REQ_OP_WRITE_SAME: 215 return 1; 216 default: 217 break; 218 } 219 220 bio_for_each_segment(bv, bio, iter) 221 segs++; 222 223 return segs; 224 } 225 226 /* 227 * get a reference to a bio, so it won't disappear. the intended use is 228 * something like: 229 * 230 * bio_get(bio); 231 * submit_bio(rw, bio); 232 * if (bio->bi_flags ...) 233 * do_something 234 * bio_put(bio); 235 * 236 * without the bio_get(), it could potentially complete I/O before submit_bio 237 * returns. and then bio would be freed memory when if (bio->bi_flags ...) 238 * runs 239 */ 240 static inline void bio_get(struct bio *bio) 241 { 242 bio->bi_flags |= (1 << BIO_REFFED); 243 smp_mb__before_atomic(); 244 atomic_inc(&bio->__bi_cnt); 245 } 246 247 static inline void bio_cnt_set(struct bio *bio, unsigned int count) 248 { 249 if (count != 1) { 250 bio->bi_flags |= (1 << BIO_REFFED); 251 smp_mb__before_atomic(); 252 } 253 atomic_set(&bio->__bi_cnt, count); 254 } 255 256 static inline bool bio_flagged(struct bio *bio, unsigned int bit) 257 { 258 return (bio->bi_flags & (1U << bit)) != 0; 259 } 260 261 static inline void bio_set_flag(struct bio *bio, unsigned int bit) 262 { 263 bio->bi_flags |= (1U << bit); 264 } 265 266 static inline void bio_clear_flag(struct bio *bio, unsigned int bit) 267 { 268 bio->bi_flags &= ~(1U << bit); 269 } 270 271 static inline void bio_get_first_bvec(struct bio *bio, struct bio_vec *bv) 272 { 273 *bv = bio_iovec(bio); 274 } 275 276 static inline void bio_get_last_bvec(struct bio *bio, struct bio_vec *bv) 277 { 278 struct bvec_iter iter = bio->bi_iter; 279 int idx; 280 281 if (unlikely(!bio_multiple_segments(bio))) { 282 *bv = bio_iovec(bio); 283 return; 284 } 285 286 bio_advance_iter(bio, &iter, iter.bi_size); 287 288 if (!iter.bi_bvec_done) 289 idx = iter.bi_idx - 1; 290 else /* in the middle of bvec */ 291 idx = iter.bi_idx; 292 293 *bv = bio->bi_io_vec[idx]; 294 295 /* 296 * iter.bi_bvec_done records actual length of the last bvec 297 * if this bio ends in the middle of one io vector 298 */ 299 if (iter.bi_bvec_done) 300 bv->bv_len = iter.bi_bvec_done; 301 } 302 303 enum bip_flags { 304 BIP_BLOCK_INTEGRITY = 1 << 0, /* block layer owns integrity data */ 305 BIP_MAPPED_INTEGRITY = 1 << 1, /* ref tag has been remapped */ 306 BIP_CTRL_NOCHECK = 1 << 2, /* disable HBA integrity checking */ 307 BIP_DISK_NOCHECK = 1 << 3, /* disable disk integrity checking */ 308 BIP_IP_CHECKSUM = 1 << 4, /* IP checksum */ 309 }; 310 311 /* 312 * bio integrity payload 313 */ 314 struct bio_integrity_payload { 315 struct bio *bip_bio; /* parent bio */ 316 317 struct bvec_iter bip_iter; 318 319 unsigned short bip_slab; /* slab the bip came from */ 320 unsigned short bip_vcnt; /* # of integrity bio_vecs */ 321 unsigned short bip_max_vcnt; /* integrity bio_vec slots */ 322 unsigned short bip_flags; /* control flags */ 323 324 struct work_struct bip_work; /* I/O completion */ 325 326 struct bio_vec *bip_vec; 327 struct bio_vec bip_inline_vecs[0];/* embedded bvec array */ 328 }; 329 330 #if defined(CONFIG_BLK_DEV_INTEGRITY) 331 332 static inline struct bio_integrity_payload *bio_integrity(struct bio *bio) 333 { 334 if (bio->bi_opf & REQ_INTEGRITY) 335 return bio->bi_integrity; 336 337 return NULL; 338 } 339 340 static inline bool bio_integrity_flagged(struct bio *bio, enum bip_flags flag) 341 { 342 struct bio_integrity_payload *bip = bio_integrity(bio); 343 344 if (bip) 345 return bip->bip_flags & flag; 346 347 return false; 348 } 349 350 static inline sector_t bip_get_seed(struct bio_integrity_payload *bip) 351 { 352 return bip->bip_iter.bi_sector; 353 } 354 355 static inline void bip_set_seed(struct bio_integrity_payload *bip, 356 sector_t seed) 357 { 358 bip->bip_iter.bi_sector = seed; 359 } 360 361 #endif /* CONFIG_BLK_DEV_INTEGRITY */ 362 363 extern void bio_trim(struct bio *bio, int offset, int size); 364 extern struct bio *bio_split(struct bio *bio, int sectors, 365 gfp_t gfp, struct bio_set *bs); 366 367 /** 368 * bio_next_split - get next @sectors from a bio, splitting if necessary 369 * @bio: bio to split 370 * @sectors: number of sectors to split from the front of @bio 371 * @gfp: gfp mask 372 * @bs: bio set to allocate from 373 * 374 * Returns a bio representing the next @sectors of @bio - if the bio is smaller 375 * than @sectors, returns the original bio unchanged. 376 */ 377 static inline struct bio *bio_next_split(struct bio *bio, int sectors, 378 gfp_t gfp, struct bio_set *bs) 379 { 380 if (sectors >= bio_sectors(bio)) 381 return bio; 382 383 return bio_split(bio, sectors, gfp, bs); 384 } 385 386 extern struct bio_set *bioset_create(unsigned int, unsigned int, int flags); 387 enum { 388 BIOSET_NEED_BVECS = BIT(0), 389 BIOSET_NEED_RESCUER = BIT(1), 390 }; 391 extern void bioset_free(struct bio_set *); 392 extern mempool_t *biovec_create_pool(int pool_entries); 393 394 extern struct bio *bio_alloc_bioset(gfp_t, unsigned int, struct bio_set *); 395 extern void bio_put(struct bio *); 396 397 extern void __bio_clone_fast(struct bio *, struct bio *); 398 extern struct bio *bio_clone_fast(struct bio *, gfp_t, struct bio_set *); 399 extern struct bio *bio_clone_bioset(struct bio *, gfp_t, struct bio_set *bs); 400 401 extern struct bio_set *fs_bio_set; 402 403 static inline struct bio *bio_alloc(gfp_t gfp_mask, unsigned int nr_iovecs) 404 { 405 return bio_alloc_bioset(gfp_mask, nr_iovecs, fs_bio_set); 406 } 407 408 static inline struct bio *bio_kmalloc(gfp_t gfp_mask, unsigned int nr_iovecs) 409 { 410 return bio_alloc_bioset(gfp_mask, nr_iovecs, NULL); 411 } 412 413 static inline struct bio *bio_clone_kmalloc(struct bio *bio, gfp_t gfp_mask) 414 { 415 return bio_clone_bioset(bio, gfp_mask, NULL); 416 417 } 418 419 extern blk_qc_t submit_bio(struct bio *); 420 421 extern void bio_endio(struct bio *); 422 423 static inline void bio_io_error(struct bio *bio) 424 { 425 bio->bi_status = BLK_STS_IOERR; 426 bio_endio(bio); 427 } 428 429 static inline void bio_wouldblock_error(struct bio *bio) 430 { 431 bio->bi_status = BLK_STS_AGAIN; 432 bio_endio(bio); 433 } 434 435 struct request_queue; 436 extern int bio_phys_segments(struct request_queue *, struct bio *); 437 438 extern int submit_bio_wait(struct bio *bio); 439 extern void bio_advance(struct bio *, unsigned); 440 441 extern void bio_init(struct bio *bio, struct bio_vec *table, 442 unsigned short max_vecs); 443 extern void bio_uninit(struct bio *); 444 extern void bio_reset(struct bio *); 445 void bio_chain(struct bio *, struct bio *); 446 447 extern int bio_add_page(struct bio *, struct page *, unsigned int,unsigned int); 448 extern int bio_add_pc_page(struct request_queue *, struct bio *, struct page *, 449 unsigned int, unsigned int); 450 int bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter); 451 struct rq_map_data; 452 extern struct bio *bio_map_user_iov(struct request_queue *, 453 struct iov_iter *, gfp_t); 454 extern void bio_unmap_user(struct bio *); 455 extern struct bio *bio_map_kern(struct request_queue *, void *, unsigned int, 456 gfp_t); 457 extern struct bio *bio_copy_kern(struct request_queue *, void *, unsigned int, 458 gfp_t, int); 459 extern void bio_set_pages_dirty(struct bio *bio); 460 extern void bio_check_pages_dirty(struct bio *bio); 461 462 void generic_start_io_acct(struct request_queue *q, int rw, 463 unsigned long sectors, struct hd_struct *part); 464 void generic_end_io_acct(struct request_queue *q, int rw, 465 struct hd_struct *part, 466 unsigned long start_time); 467 468 #ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 469 # error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform" 470 #endif 471 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 472 extern void bio_flush_dcache_pages(struct bio *bi); 473 #else 474 static inline void bio_flush_dcache_pages(struct bio *bi) 475 { 476 } 477 #endif 478 479 extern void bio_copy_data(struct bio *dst, struct bio *src); 480 extern int bio_alloc_pages(struct bio *bio, gfp_t gfp); 481 extern void bio_free_pages(struct bio *bio); 482 483 extern struct bio *bio_copy_user_iov(struct request_queue *, 484 struct rq_map_data *, 485 struct iov_iter *, 486 gfp_t); 487 extern int bio_uncopy_user(struct bio *); 488 void zero_fill_bio(struct bio *bio); 489 extern struct bio_vec *bvec_alloc(gfp_t, int, unsigned long *, mempool_t *); 490 extern void bvec_free(mempool_t *, struct bio_vec *, unsigned int); 491 extern unsigned int bvec_nr_vecs(unsigned short idx); 492 493 #define bio_set_dev(bio, bdev) \ 494 do { \ 495 (bio)->bi_disk = (bdev)->bd_disk; \ 496 (bio)->bi_partno = (bdev)->bd_partno; \ 497 } while (0) 498 499 #define bio_copy_dev(dst, src) \ 500 do { \ 501 (dst)->bi_disk = (src)->bi_disk; \ 502 (dst)->bi_partno = (src)->bi_partno; \ 503 } while (0) 504 505 #define bio_dev(bio) \ 506 disk_devt((bio)->bi_disk) 507 508 #define bio_devname(bio, buf) \ 509 __bdevname(bio_dev(bio), (buf)) 510 511 #ifdef CONFIG_BLK_CGROUP 512 int bio_associate_blkcg(struct bio *bio, struct cgroup_subsys_state *blkcg_css); 513 void bio_disassociate_task(struct bio *bio); 514 void bio_clone_blkcg_association(struct bio *dst, struct bio *src); 515 #else /* CONFIG_BLK_CGROUP */ 516 static inline int bio_associate_blkcg(struct bio *bio, 517 struct cgroup_subsys_state *blkcg_css) { return 0; } 518 static inline void bio_disassociate_task(struct bio *bio) { } 519 static inline void bio_clone_blkcg_association(struct bio *dst, 520 struct bio *src) { } 521 #endif /* CONFIG_BLK_CGROUP */ 522 523 #ifdef CONFIG_HIGHMEM 524 /* 525 * remember never ever reenable interrupts between a bvec_kmap_irq and 526 * bvec_kunmap_irq! 527 */ 528 static inline char *bvec_kmap_irq(struct bio_vec *bvec, unsigned long *flags) 529 { 530 unsigned long addr; 531 532 /* 533 * might not be a highmem page, but the preempt/irq count 534 * balancing is a lot nicer this way 535 */ 536 local_irq_save(*flags); 537 addr = (unsigned long) kmap_atomic(bvec->bv_page); 538 539 BUG_ON(addr & ~PAGE_MASK); 540 541 return (char *) addr + bvec->bv_offset; 542 } 543 544 static inline void bvec_kunmap_irq(char *buffer, unsigned long *flags) 545 { 546 unsigned long ptr = (unsigned long) buffer & PAGE_MASK; 547 548 kunmap_atomic((void *) ptr); 549 local_irq_restore(*flags); 550 } 551 552 #else 553 static inline char *bvec_kmap_irq(struct bio_vec *bvec, unsigned long *flags) 554 { 555 return page_address(bvec->bv_page) + bvec->bv_offset; 556 } 557 558 static inline void bvec_kunmap_irq(char *buffer, unsigned long *flags) 559 { 560 *flags = 0; 561 } 562 #endif 563 564 /* 565 * BIO list management for use by remapping drivers (e.g. DM or MD) and loop. 566 * 567 * A bio_list anchors a singly-linked list of bios chained through the bi_next 568 * member of the bio. The bio_list also caches the last list member to allow 569 * fast access to the tail. 570 */ 571 struct bio_list { 572 struct bio *head; 573 struct bio *tail; 574 }; 575 576 static inline int bio_list_empty(const struct bio_list *bl) 577 { 578 return bl->head == NULL; 579 } 580 581 static inline void bio_list_init(struct bio_list *bl) 582 { 583 bl->head = bl->tail = NULL; 584 } 585 586 #define BIO_EMPTY_LIST { NULL, NULL } 587 588 #define bio_list_for_each(bio, bl) \ 589 for (bio = (bl)->head; bio; bio = bio->bi_next) 590 591 static inline unsigned bio_list_size(const struct bio_list *bl) 592 { 593 unsigned sz = 0; 594 struct bio *bio; 595 596 bio_list_for_each(bio, bl) 597 sz++; 598 599 return sz; 600 } 601 602 static inline void bio_list_add(struct bio_list *bl, struct bio *bio) 603 { 604 bio->bi_next = NULL; 605 606 if (bl->tail) 607 bl->tail->bi_next = bio; 608 else 609 bl->head = bio; 610 611 bl->tail = bio; 612 } 613 614 static inline void bio_list_add_head(struct bio_list *bl, struct bio *bio) 615 { 616 bio->bi_next = bl->head; 617 618 bl->head = bio; 619 620 if (!bl->tail) 621 bl->tail = bio; 622 } 623 624 static inline void bio_list_merge(struct bio_list *bl, struct bio_list *bl2) 625 { 626 if (!bl2->head) 627 return; 628 629 if (bl->tail) 630 bl->tail->bi_next = bl2->head; 631 else 632 bl->head = bl2->head; 633 634 bl->tail = bl2->tail; 635 } 636 637 static inline void bio_list_merge_head(struct bio_list *bl, 638 struct bio_list *bl2) 639 { 640 if (!bl2->head) 641 return; 642 643 if (bl->head) 644 bl2->tail->bi_next = bl->head; 645 else 646 bl->tail = bl2->tail; 647 648 bl->head = bl2->head; 649 } 650 651 static inline struct bio *bio_list_peek(struct bio_list *bl) 652 { 653 return bl->head; 654 } 655 656 static inline struct bio *bio_list_pop(struct bio_list *bl) 657 { 658 struct bio *bio = bl->head; 659 660 if (bio) { 661 bl->head = bl->head->bi_next; 662 if (!bl->head) 663 bl->tail = NULL; 664 665 bio->bi_next = NULL; 666 } 667 668 return bio; 669 } 670 671 static inline struct bio *bio_list_get(struct bio_list *bl) 672 { 673 struct bio *bio = bl->head; 674 675 bl->head = bl->tail = NULL; 676 677 return bio; 678 } 679 680 /* 681 * Increment chain count for the bio. Make sure the CHAIN flag update 682 * is visible before the raised count. 683 */ 684 static inline void bio_inc_remaining(struct bio *bio) 685 { 686 bio_set_flag(bio, BIO_CHAIN); 687 smp_mb__before_atomic(); 688 atomic_inc(&bio->__bi_remaining); 689 } 690 691 /* 692 * bio_set is used to allow other portions of the IO system to 693 * allocate their own private memory pools for bio and iovec structures. 694 * These memory pools in turn all allocate from the bio_slab 695 * and the bvec_slabs[]. 696 */ 697 #define BIO_POOL_SIZE 2 698 699 struct bio_set { 700 struct kmem_cache *bio_slab; 701 unsigned int front_pad; 702 703 mempool_t *bio_pool; 704 mempool_t *bvec_pool; 705 #if defined(CONFIG_BLK_DEV_INTEGRITY) 706 mempool_t *bio_integrity_pool; 707 mempool_t *bvec_integrity_pool; 708 #endif 709 710 /* 711 * Deadlock avoidance for stacking block drivers: see comments in 712 * bio_alloc_bioset() for details 713 */ 714 spinlock_t rescue_lock; 715 struct bio_list rescue_list; 716 struct work_struct rescue_work; 717 struct workqueue_struct *rescue_workqueue; 718 }; 719 720 struct biovec_slab { 721 int nr_vecs; 722 char *name; 723 struct kmem_cache *slab; 724 }; 725 726 /* 727 * a small number of entries is fine, not going to be performance critical. 728 * basically we just need to survive 729 */ 730 #define BIO_SPLIT_ENTRIES 2 731 732 #if defined(CONFIG_BLK_DEV_INTEGRITY) 733 734 #define bip_for_each_vec(bvl, bip, iter) \ 735 for_each_bvec(bvl, (bip)->bip_vec, iter, (bip)->bip_iter) 736 737 #define bio_for_each_integrity_vec(_bvl, _bio, _iter) \ 738 for_each_bio(_bio) \ 739 bip_for_each_vec(_bvl, _bio->bi_integrity, _iter) 740 741 extern struct bio_integrity_payload *bio_integrity_alloc(struct bio *, gfp_t, unsigned int); 742 extern int bio_integrity_add_page(struct bio *, struct page *, unsigned int, unsigned int); 743 extern bool bio_integrity_prep(struct bio *); 744 extern void bio_integrity_advance(struct bio *, unsigned int); 745 extern void bio_integrity_trim(struct bio *); 746 extern int bio_integrity_clone(struct bio *, struct bio *, gfp_t); 747 extern int bioset_integrity_create(struct bio_set *, int); 748 extern void bioset_integrity_free(struct bio_set *); 749 extern void bio_integrity_init(void); 750 751 #else /* CONFIG_BLK_DEV_INTEGRITY */ 752 753 static inline void *bio_integrity(struct bio *bio) 754 { 755 return NULL; 756 } 757 758 static inline int bioset_integrity_create(struct bio_set *bs, int pool_size) 759 { 760 return 0; 761 } 762 763 static inline void bioset_integrity_free (struct bio_set *bs) 764 { 765 return; 766 } 767 768 static inline bool bio_integrity_prep(struct bio *bio) 769 { 770 return true; 771 } 772 773 static inline int bio_integrity_clone(struct bio *bio, struct bio *bio_src, 774 gfp_t gfp_mask) 775 { 776 return 0; 777 } 778 779 static inline void bio_integrity_advance(struct bio *bio, 780 unsigned int bytes_done) 781 { 782 return; 783 } 784 785 static inline void bio_integrity_trim(struct bio *bio) 786 { 787 return; 788 } 789 790 static inline void bio_integrity_init(void) 791 { 792 return; 793 } 794 795 static inline bool bio_integrity_flagged(struct bio *bio, enum bip_flags flag) 796 { 797 return false; 798 } 799 800 static inline void *bio_integrity_alloc(struct bio * bio, gfp_t gfp, 801 unsigned int nr) 802 { 803 return ERR_PTR(-EINVAL); 804 } 805 806 static inline int bio_integrity_add_page(struct bio *bio, struct page *page, 807 unsigned int len, unsigned int offset) 808 { 809 return 0; 810 } 811 812 #endif /* CONFIG_BLK_DEV_INTEGRITY */ 813 814 #endif /* CONFIG_BLOCK */ 815 #endif /* __LINUX_BIO_H */ 816