1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * Copyright (C) 2001 Jens Axboe <axboe@suse.de> 4 */ 5 #ifndef __LINUX_BIO_H 6 #define __LINUX_BIO_H 7 8 #include <linux/highmem.h> 9 #include <linux/mempool.h> 10 #include <linux/ioprio.h> 11 12 #ifdef CONFIG_BLOCK 13 /* struct bio, bio_vec and BIO_* flags are defined in blk_types.h */ 14 #include <linux/blk_types.h> 15 16 #define BIO_DEBUG 17 18 #ifdef BIO_DEBUG 19 #define BIO_BUG_ON BUG_ON 20 #else 21 #define BIO_BUG_ON 22 #endif 23 24 #define BIO_MAX_PAGES 256 25 26 #define bio_prio(bio) (bio)->bi_ioprio 27 #define bio_set_prio(bio, prio) ((bio)->bi_ioprio = prio) 28 29 #define bio_iter_iovec(bio, iter) \ 30 bvec_iter_bvec((bio)->bi_io_vec, (iter)) 31 32 #define bio_iter_page(bio, iter) \ 33 bvec_iter_page((bio)->bi_io_vec, (iter)) 34 #define bio_iter_len(bio, iter) \ 35 bvec_iter_len((bio)->bi_io_vec, (iter)) 36 #define bio_iter_offset(bio, iter) \ 37 bvec_iter_offset((bio)->bi_io_vec, (iter)) 38 39 #define bio_page(bio) bio_iter_page((bio), (bio)->bi_iter) 40 #define bio_offset(bio) bio_iter_offset((bio), (bio)->bi_iter) 41 #define bio_iovec(bio) bio_iter_iovec((bio), (bio)->bi_iter) 42 43 #define bio_multiple_segments(bio) \ 44 ((bio)->bi_iter.bi_size != bio_iovec(bio).bv_len) 45 46 #define bvec_iter_sectors(iter) ((iter).bi_size >> 9) 47 #define bvec_iter_end_sector(iter) ((iter).bi_sector + bvec_iter_sectors((iter))) 48 49 #define bio_sectors(bio) bvec_iter_sectors((bio)->bi_iter) 50 #define bio_end_sector(bio) bvec_iter_end_sector((bio)->bi_iter) 51 52 /* 53 * Return the data direction, READ or WRITE. 54 */ 55 #define bio_data_dir(bio) \ 56 (op_is_write(bio_op(bio)) ? WRITE : READ) 57 58 /* 59 * Check whether this bio carries any data or not. A NULL bio is allowed. 60 */ 61 static inline bool bio_has_data(struct bio *bio) 62 { 63 if (bio && 64 bio->bi_iter.bi_size && 65 bio_op(bio) != REQ_OP_DISCARD && 66 bio_op(bio) != REQ_OP_SECURE_ERASE && 67 bio_op(bio) != REQ_OP_WRITE_ZEROES) 68 return true; 69 70 return false; 71 } 72 73 static inline bool bio_no_advance_iter(struct bio *bio) 74 { 75 return bio_op(bio) == REQ_OP_DISCARD || 76 bio_op(bio) == REQ_OP_SECURE_ERASE || 77 bio_op(bio) == REQ_OP_WRITE_SAME || 78 bio_op(bio) == REQ_OP_WRITE_ZEROES; 79 } 80 81 static inline bool bio_mergeable(struct bio *bio) 82 { 83 if (bio->bi_opf & REQ_NOMERGE_FLAGS) 84 return false; 85 86 return true; 87 } 88 89 static inline unsigned int bio_cur_bytes(struct bio *bio) 90 { 91 if (bio_has_data(bio)) 92 return bio_iovec(bio).bv_len; 93 else /* dataless requests such as discard */ 94 return bio->bi_iter.bi_size; 95 } 96 97 static inline void *bio_data(struct bio *bio) 98 { 99 if (bio_has_data(bio)) 100 return page_address(bio_page(bio)) + bio_offset(bio); 101 102 return NULL; 103 } 104 105 /** 106 * bio_full - check if the bio is full 107 * @bio: bio to check 108 * @len: length of one segment to be added 109 * 110 * Return true if @bio is full and one segment with @len bytes can't be 111 * added to the bio, otherwise return false 112 */ 113 static inline bool bio_full(struct bio *bio, unsigned len) 114 { 115 if (bio->bi_vcnt >= bio->bi_max_vecs) 116 return true; 117 118 if (bio->bi_iter.bi_size > UINT_MAX - len) 119 return true; 120 121 return false; 122 } 123 124 static inline bool bio_next_segment(const struct bio *bio, 125 struct bvec_iter_all *iter) 126 { 127 if (iter->idx >= bio->bi_vcnt) 128 return false; 129 130 bvec_advance(&bio->bi_io_vec[iter->idx], iter); 131 return true; 132 } 133 134 /* 135 * drivers should _never_ use the all version - the bio may have been split 136 * before it got to the driver and the driver won't own all of it 137 */ 138 #define bio_for_each_segment_all(bvl, bio, iter) \ 139 for (bvl = bvec_init_iter_all(&iter); bio_next_segment((bio), &iter); ) 140 141 static inline void bio_advance_iter(struct bio *bio, struct bvec_iter *iter, 142 unsigned bytes) 143 { 144 iter->bi_sector += bytes >> 9; 145 146 if (bio_no_advance_iter(bio)) 147 iter->bi_size -= bytes; 148 else 149 bvec_iter_advance(bio->bi_io_vec, iter, bytes); 150 /* TODO: It is reasonable to complete bio with error here. */ 151 } 152 153 #define __bio_for_each_segment(bvl, bio, iter, start) \ 154 for (iter = (start); \ 155 (iter).bi_size && \ 156 ((bvl = bio_iter_iovec((bio), (iter))), 1); \ 157 bio_advance_iter((bio), &(iter), (bvl).bv_len)) 158 159 #define bio_for_each_segment(bvl, bio, iter) \ 160 __bio_for_each_segment(bvl, bio, iter, (bio)->bi_iter) 161 162 #define __bio_for_each_bvec(bvl, bio, iter, start) \ 163 for (iter = (start); \ 164 (iter).bi_size && \ 165 ((bvl = mp_bvec_iter_bvec((bio)->bi_io_vec, (iter))), 1); \ 166 bio_advance_iter((bio), &(iter), (bvl).bv_len)) 167 168 /* iterate over multi-page bvec */ 169 #define bio_for_each_bvec(bvl, bio, iter) \ 170 __bio_for_each_bvec(bvl, bio, iter, (bio)->bi_iter) 171 172 #define bio_iter_last(bvec, iter) ((iter).bi_size == (bvec).bv_len) 173 174 static inline unsigned bio_segments(struct bio *bio) 175 { 176 unsigned segs = 0; 177 struct bio_vec bv; 178 struct bvec_iter iter; 179 180 /* 181 * We special case discard/write same/write zeroes, because they 182 * interpret bi_size differently: 183 */ 184 185 switch (bio_op(bio)) { 186 case REQ_OP_DISCARD: 187 case REQ_OP_SECURE_ERASE: 188 case REQ_OP_WRITE_ZEROES: 189 return 0; 190 case REQ_OP_WRITE_SAME: 191 return 1; 192 default: 193 break; 194 } 195 196 bio_for_each_segment(bv, bio, iter) 197 segs++; 198 199 return segs; 200 } 201 202 /* 203 * get a reference to a bio, so it won't disappear. the intended use is 204 * something like: 205 * 206 * bio_get(bio); 207 * submit_bio(rw, bio); 208 * if (bio->bi_flags ...) 209 * do_something 210 * bio_put(bio); 211 * 212 * without the bio_get(), it could potentially complete I/O before submit_bio 213 * returns. and then bio would be freed memory when if (bio->bi_flags ...) 214 * runs 215 */ 216 static inline void bio_get(struct bio *bio) 217 { 218 bio->bi_flags |= (1 << BIO_REFFED); 219 smp_mb__before_atomic(); 220 atomic_inc(&bio->__bi_cnt); 221 } 222 223 static inline void bio_cnt_set(struct bio *bio, unsigned int count) 224 { 225 if (count != 1) { 226 bio->bi_flags |= (1 << BIO_REFFED); 227 smp_mb(); 228 } 229 atomic_set(&bio->__bi_cnt, count); 230 } 231 232 static inline bool bio_flagged(struct bio *bio, unsigned int bit) 233 { 234 return (bio->bi_flags & (1U << bit)) != 0; 235 } 236 237 static inline void bio_set_flag(struct bio *bio, unsigned int bit) 238 { 239 bio->bi_flags |= (1U << bit); 240 } 241 242 static inline void bio_clear_flag(struct bio *bio, unsigned int bit) 243 { 244 bio->bi_flags &= ~(1U << bit); 245 } 246 247 static inline void bio_get_first_bvec(struct bio *bio, struct bio_vec *bv) 248 { 249 *bv = bio_iovec(bio); 250 } 251 252 static inline void bio_get_last_bvec(struct bio *bio, struct bio_vec *bv) 253 { 254 struct bvec_iter iter = bio->bi_iter; 255 int idx; 256 257 if (unlikely(!bio_multiple_segments(bio))) { 258 *bv = bio_iovec(bio); 259 return; 260 } 261 262 bio_advance_iter(bio, &iter, iter.bi_size); 263 264 if (!iter.bi_bvec_done) 265 idx = iter.bi_idx - 1; 266 else /* in the middle of bvec */ 267 idx = iter.bi_idx; 268 269 *bv = bio->bi_io_vec[idx]; 270 271 /* 272 * iter.bi_bvec_done records actual length of the last bvec 273 * if this bio ends in the middle of one io vector 274 */ 275 if (iter.bi_bvec_done) 276 bv->bv_len = iter.bi_bvec_done; 277 } 278 279 static inline struct bio_vec *bio_first_bvec_all(struct bio *bio) 280 { 281 WARN_ON_ONCE(bio_flagged(bio, BIO_CLONED)); 282 return bio->bi_io_vec; 283 } 284 285 static inline struct page *bio_first_page_all(struct bio *bio) 286 { 287 return bio_first_bvec_all(bio)->bv_page; 288 } 289 290 static inline struct bio_vec *bio_last_bvec_all(struct bio *bio) 291 { 292 WARN_ON_ONCE(bio_flagged(bio, BIO_CLONED)); 293 return &bio->bi_io_vec[bio->bi_vcnt - 1]; 294 } 295 296 enum bip_flags { 297 BIP_BLOCK_INTEGRITY = 1 << 0, /* block layer owns integrity data */ 298 BIP_MAPPED_INTEGRITY = 1 << 1, /* ref tag has been remapped */ 299 BIP_CTRL_NOCHECK = 1 << 2, /* disable HBA integrity checking */ 300 BIP_DISK_NOCHECK = 1 << 3, /* disable disk integrity checking */ 301 BIP_IP_CHECKSUM = 1 << 4, /* IP checksum */ 302 }; 303 304 /* 305 * bio integrity payload 306 */ 307 struct bio_integrity_payload { 308 struct bio *bip_bio; /* parent bio */ 309 310 struct bvec_iter bip_iter; 311 312 unsigned short bip_slab; /* slab the bip came from */ 313 unsigned short bip_vcnt; /* # of integrity bio_vecs */ 314 unsigned short bip_max_vcnt; /* integrity bio_vec slots */ 315 unsigned short bip_flags; /* control flags */ 316 317 struct bvec_iter bio_iter; /* for rewinding parent bio */ 318 319 struct work_struct bip_work; /* I/O completion */ 320 321 struct bio_vec *bip_vec; 322 struct bio_vec bip_inline_vecs[];/* embedded bvec array */ 323 }; 324 325 #if defined(CONFIG_BLK_DEV_INTEGRITY) 326 327 static inline struct bio_integrity_payload *bio_integrity(struct bio *bio) 328 { 329 if (bio->bi_opf & REQ_INTEGRITY) 330 return bio->bi_integrity; 331 332 return NULL; 333 } 334 335 static inline bool bio_integrity_flagged(struct bio *bio, enum bip_flags flag) 336 { 337 struct bio_integrity_payload *bip = bio_integrity(bio); 338 339 if (bip) 340 return bip->bip_flags & flag; 341 342 return false; 343 } 344 345 static inline sector_t bip_get_seed(struct bio_integrity_payload *bip) 346 { 347 return bip->bip_iter.bi_sector; 348 } 349 350 static inline void bip_set_seed(struct bio_integrity_payload *bip, 351 sector_t seed) 352 { 353 bip->bip_iter.bi_sector = seed; 354 } 355 356 #endif /* CONFIG_BLK_DEV_INTEGRITY */ 357 358 extern void bio_trim(struct bio *bio, int offset, int size); 359 extern struct bio *bio_split(struct bio *bio, int sectors, 360 gfp_t gfp, struct bio_set *bs); 361 362 /** 363 * bio_next_split - get next @sectors from a bio, splitting if necessary 364 * @bio: bio to split 365 * @sectors: number of sectors to split from the front of @bio 366 * @gfp: gfp mask 367 * @bs: bio set to allocate from 368 * 369 * Returns a bio representing the next @sectors of @bio - if the bio is smaller 370 * than @sectors, returns the original bio unchanged. 371 */ 372 static inline struct bio *bio_next_split(struct bio *bio, int sectors, 373 gfp_t gfp, struct bio_set *bs) 374 { 375 if (sectors >= bio_sectors(bio)) 376 return bio; 377 378 return bio_split(bio, sectors, gfp, bs); 379 } 380 381 enum { 382 BIOSET_NEED_BVECS = BIT(0), 383 BIOSET_NEED_RESCUER = BIT(1), 384 }; 385 extern int bioset_init(struct bio_set *, unsigned int, unsigned int, int flags); 386 extern void bioset_exit(struct bio_set *); 387 extern int biovec_init_pool(mempool_t *pool, int pool_entries); 388 extern int bioset_init_from_src(struct bio_set *bs, struct bio_set *src); 389 390 extern struct bio *bio_alloc_bioset(gfp_t, unsigned int, struct bio_set *); 391 extern void bio_put(struct bio *); 392 393 extern void __bio_clone_fast(struct bio *, struct bio *); 394 extern struct bio *bio_clone_fast(struct bio *, gfp_t, struct bio_set *); 395 396 extern struct bio_set fs_bio_set; 397 398 static inline struct bio *bio_alloc(gfp_t gfp_mask, unsigned int nr_iovecs) 399 { 400 return bio_alloc_bioset(gfp_mask, nr_iovecs, &fs_bio_set); 401 } 402 403 static inline struct bio *bio_kmalloc(gfp_t gfp_mask, unsigned int nr_iovecs) 404 { 405 return bio_alloc_bioset(gfp_mask, nr_iovecs, NULL); 406 } 407 408 extern blk_qc_t submit_bio(struct bio *); 409 410 extern void bio_endio(struct bio *); 411 412 static inline void bio_io_error(struct bio *bio) 413 { 414 bio->bi_status = BLK_STS_IOERR; 415 bio_endio(bio); 416 } 417 418 static inline void bio_wouldblock_error(struct bio *bio) 419 { 420 bio->bi_status = BLK_STS_AGAIN; 421 bio_endio(bio); 422 } 423 424 struct request_queue; 425 426 extern int submit_bio_wait(struct bio *bio); 427 extern void bio_advance(struct bio *, unsigned); 428 429 extern void bio_init(struct bio *bio, struct bio_vec *table, 430 unsigned short max_vecs); 431 extern void bio_uninit(struct bio *); 432 extern void bio_reset(struct bio *); 433 void bio_chain(struct bio *, struct bio *); 434 435 extern int bio_add_page(struct bio *, struct page *, unsigned int,unsigned int); 436 extern int bio_add_pc_page(struct request_queue *, struct bio *, struct page *, 437 unsigned int, unsigned int); 438 bool __bio_try_merge_page(struct bio *bio, struct page *page, 439 unsigned int len, unsigned int off, bool *same_page); 440 void __bio_add_page(struct bio *bio, struct page *page, 441 unsigned int len, unsigned int off); 442 int bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter); 443 void bio_release_pages(struct bio *bio, bool mark_dirty); 444 extern void bio_set_pages_dirty(struct bio *bio); 445 extern void bio_check_pages_dirty(struct bio *bio); 446 447 void generic_start_io_acct(struct request_queue *q, int op, 448 unsigned long sectors, struct hd_struct *part); 449 void generic_end_io_acct(struct request_queue *q, int op, 450 struct hd_struct *part, 451 unsigned long start_time); 452 453 extern void bio_copy_data_iter(struct bio *dst, struct bvec_iter *dst_iter, 454 struct bio *src, struct bvec_iter *src_iter); 455 extern void bio_copy_data(struct bio *dst, struct bio *src); 456 extern void bio_list_copy_data(struct bio *dst, struct bio *src); 457 extern void bio_free_pages(struct bio *bio); 458 void zero_fill_bio_iter(struct bio *bio, struct bvec_iter iter); 459 void bio_truncate(struct bio *bio, unsigned new_size); 460 void guard_bio_eod(struct bio *bio); 461 462 static inline void zero_fill_bio(struct bio *bio) 463 { 464 zero_fill_bio_iter(bio, bio->bi_iter); 465 } 466 467 extern struct bio_vec *bvec_alloc(gfp_t, int, unsigned long *, mempool_t *); 468 extern void bvec_free(mempool_t *, struct bio_vec *, unsigned int); 469 extern unsigned int bvec_nr_vecs(unsigned short idx); 470 extern const char *bio_devname(struct bio *bio, char *buffer); 471 472 #define bio_set_dev(bio, bdev) \ 473 do { \ 474 if ((bio)->bi_disk != (bdev)->bd_disk) \ 475 bio_clear_flag(bio, BIO_THROTTLED);\ 476 (bio)->bi_disk = (bdev)->bd_disk; \ 477 (bio)->bi_partno = (bdev)->bd_partno; \ 478 bio_associate_blkg(bio); \ 479 } while (0) 480 481 #define bio_copy_dev(dst, src) \ 482 do { \ 483 (dst)->bi_disk = (src)->bi_disk; \ 484 (dst)->bi_partno = (src)->bi_partno; \ 485 bio_clone_blkg_association(dst, src); \ 486 } while (0) 487 488 #define bio_dev(bio) \ 489 disk_devt((bio)->bi_disk) 490 491 #if defined(CONFIG_MEMCG) && defined(CONFIG_BLK_CGROUP) 492 void bio_associate_blkg_from_page(struct bio *bio, struct page *page); 493 #else 494 static inline void bio_associate_blkg_from_page(struct bio *bio, 495 struct page *page) { } 496 #endif 497 498 #ifdef CONFIG_BLK_CGROUP 499 void bio_disassociate_blkg(struct bio *bio); 500 void bio_associate_blkg(struct bio *bio); 501 void bio_associate_blkg_from_css(struct bio *bio, 502 struct cgroup_subsys_state *css); 503 void bio_clone_blkg_association(struct bio *dst, struct bio *src); 504 #else /* CONFIG_BLK_CGROUP */ 505 static inline void bio_disassociate_blkg(struct bio *bio) { } 506 static inline void bio_associate_blkg(struct bio *bio) { } 507 static inline void bio_associate_blkg_from_css(struct bio *bio, 508 struct cgroup_subsys_state *css) 509 { } 510 static inline void bio_clone_blkg_association(struct bio *dst, 511 struct bio *src) { } 512 #endif /* CONFIG_BLK_CGROUP */ 513 514 #ifdef CONFIG_HIGHMEM 515 /* 516 * remember never ever reenable interrupts between a bvec_kmap_irq and 517 * bvec_kunmap_irq! 518 */ 519 static inline char *bvec_kmap_irq(struct bio_vec *bvec, unsigned long *flags) 520 { 521 unsigned long addr; 522 523 /* 524 * might not be a highmem page, but the preempt/irq count 525 * balancing is a lot nicer this way 526 */ 527 local_irq_save(*flags); 528 addr = (unsigned long) kmap_atomic(bvec->bv_page); 529 530 BUG_ON(addr & ~PAGE_MASK); 531 532 return (char *) addr + bvec->bv_offset; 533 } 534 535 static inline void bvec_kunmap_irq(char *buffer, unsigned long *flags) 536 { 537 unsigned long ptr = (unsigned long) buffer & PAGE_MASK; 538 539 kunmap_atomic((void *) ptr); 540 local_irq_restore(*flags); 541 } 542 543 #else 544 static inline char *bvec_kmap_irq(struct bio_vec *bvec, unsigned long *flags) 545 { 546 return page_address(bvec->bv_page) + bvec->bv_offset; 547 } 548 549 static inline void bvec_kunmap_irq(char *buffer, unsigned long *flags) 550 { 551 *flags = 0; 552 } 553 #endif 554 555 /* 556 * BIO list management for use by remapping drivers (e.g. DM or MD) and loop. 557 * 558 * A bio_list anchors a singly-linked list of bios chained through the bi_next 559 * member of the bio. The bio_list also caches the last list member to allow 560 * fast access to the tail. 561 */ 562 struct bio_list { 563 struct bio *head; 564 struct bio *tail; 565 }; 566 567 static inline int bio_list_empty(const struct bio_list *bl) 568 { 569 return bl->head == NULL; 570 } 571 572 static inline void bio_list_init(struct bio_list *bl) 573 { 574 bl->head = bl->tail = NULL; 575 } 576 577 #define BIO_EMPTY_LIST { NULL, NULL } 578 579 #define bio_list_for_each(bio, bl) \ 580 for (bio = (bl)->head; bio; bio = bio->bi_next) 581 582 static inline unsigned bio_list_size(const struct bio_list *bl) 583 { 584 unsigned sz = 0; 585 struct bio *bio; 586 587 bio_list_for_each(bio, bl) 588 sz++; 589 590 return sz; 591 } 592 593 static inline void bio_list_add(struct bio_list *bl, struct bio *bio) 594 { 595 bio->bi_next = NULL; 596 597 if (bl->tail) 598 bl->tail->bi_next = bio; 599 else 600 bl->head = bio; 601 602 bl->tail = bio; 603 } 604 605 static inline void bio_list_add_head(struct bio_list *bl, struct bio *bio) 606 { 607 bio->bi_next = bl->head; 608 609 bl->head = bio; 610 611 if (!bl->tail) 612 bl->tail = bio; 613 } 614 615 static inline void bio_list_merge(struct bio_list *bl, struct bio_list *bl2) 616 { 617 if (!bl2->head) 618 return; 619 620 if (bl->tail) 621 bl->tail->bi_next = bl2->head; 622 else 623 bl->head = bl2->head; 624 625 bl->tail = bl2->tail; 626 } 627 628 static inline void bio_list_merge_head(struct bio_list *bl, 629 struct bio_list *bl2) 630 { 631 if (!bl2->head) 632 return; 633 634 if (bl->head) 635 bl2->tail->bi_next = bl->head; 636 else 637 bl->tail = bl2->tail; 638 639 bl->head = bl2->head; 640 } 641 642 static inline struct bio *bio_list_peek(struct bio_list *bl) 643 { 644 return bl->head; 645 } 646 647 static inline struct bio *bio_list_pop(struct bio_list *bl) 648 { 649 struct bio *bio = bl->head; 650 651 if (bio) { 652 bl->head = bl->head->bi_next; 653 if (!bl->head) 654 bl->tail = NULL; 655 656 bio->bi_next = NULL; 657 } 658 659 return bio; 660 } 661 662 static inline struct bio *bio_list_get(struct bio_list *bl) 663 { 664 struct bio *bio = bl->head; 665 666 bl->head = bl->tail = NULL; 667 668 return bio; 669 } 670 671 /* 672 * Increment chain count for the bio. Make sure the CHAIN flag update 673 * is visible before the raised count. 674 */ 675 static inline void bio_inc_remaining(struct bio *bio) 676 { 677 bio_set_flag(bio, BIO_CHAIN); 678 smp_mb__before_atomic(); 679 atomic_inc(&bio->__bi_remaining); 680 } 681 682 /* 683 * bio_set is used to allow other portions of the IO system to 684 * allocate their own private memory pools for bio and iovec structures. 685 * These memory pools in turn all allocate from the bio_slab 686 * and the bvec_slabs[]. 687 */ 688 #define BIO_POOL_SIZE 2 689 690 struct bio_set { 691 struct kmem_cache *bio_slab; 692 unsigned int front_pad; 693 694 mempool_t bio_pool; 695 mempool_t bvec_pool; 696 #if defined(CONFIG_BLK_DEV_INTEGRITY) 697 mempool_t bio_integrity_pool; 698 mempool_t bvec_integrity_pool; 699 #endif 700 701 /* 702 * Deadlock avoidance for stacking block drivers: see comments in 703 * bio_alloc_bioset() for details 704 */ 705 spinlock_t rescue_lock; 706 struct bio_list rescue_list; 707 struct work_struct rescue_work; 708 struct workqueue_struct *rescue_workqueue; 709 }; 710 711 struct biovec_slab { 712 int nr_vecs; 713 char *name; 714 struct kmem_cache *slab; 715 }; 716 717 static inline bool bioset_initialized(struct bio_set *bs) 718 { 719 return bs->bio_slab != NULL; 720 } 721 722 /* 723 * a small number of entries is fine, not going to be performance critical. 724 * basically we just need to survive 725 */ 726 #define BIO_SPLIT_ENTRIES 2 727 728 #if defined(CONFIG_BLK_DEV_INTEGRITY) 729 730 #define bip_for_each_vec(bvl, bip, iter) \ 731 for_each_bvec(bvl, (bip)->bip_vec, iter, (bip)->bip_iter) 732 733 #define bio_for_each_integrity_vec(_bvl, _bio, _iter) \ 734 for_each_bio(_bio) \ 735 bip_for_each_vec(_bvl, _bio->bi_integrity, _iter) 736 737 extern struct bio_integrity_payload *bio_integrity_alloc(struct bio *, gfp_t, unsigned int); 738 extern int bio_integrity_add_page(struct bio *, struct page *, unsigned int, unsigned int); 739 extern bool bio_integrity_prep(struct bio *); 740 extern void bio_integrity_advance(struct bio *, unsigned int); 741 extern void bio_integrity_trim(struct bio *); 742 extern int bio_integrity_clone(struct bio *, struct bio *, gfp_t); 743 extern int bioset_integrity_create(struct bio_set *, int); 744 extern void bioset_integrity_free(struct bio_set *); 745 extern void bio_integrity_init(void); 746 747 #else /* CONFIG_BLK_DEV_INTEGRITY */ 748 749 static inline void *bio_integrity(struct bio *bio) 750 { 751 return NULL; 752 } 753 754 static inline int bioset_integrity_create(struct bio_set *bs, int pool_size) 755 { 756 return 0; 757 } 758 759 static inline void bioset_integrity_free (struct bio_set *bs) 760 { 761 return; 762 } 763 764 static inline bool bio_integrity_prep(struct bio *bio) 765 { 766 return true; 767 } 768 769 static inline int bio_integrity_clone(struct bio *bio, struct bio *bio_src, 770 gfp_t gfp_mask) 771 { 772 return 0; 773 } 774 775 static inline void bio_integrity_advance(struct bio *bio, 776 unsigned int bytes_done) 777 { 778 return; 779 } 780 781 static inline void bio_integrity_trim(struct bio *bio) 782 { 783 return; 784 } 785 786 static inline void bio_integrity_init(void) 787 { 788 return; 789 } 790 791 static inline bool bio_integrity_flagged(struct bio *bio, enum bip_flags flag) 792 { 793 return false; 794 } 795 796 static inline void *bio_integrity_alloc(struct bio * bio, gfp_t gfp, 797 unsigned int nr) 798 { 799 return ERR_PTR(-EINVAL); 800 } 801 802 static inline int bio_integrity_add_page(struct bio *bio, struct page *page, 803 unsigned int len, unsigned int offset) 804 { 805 return 0; 806 } 807 808 #endif /* CONFIG_BLK_DEV_INTEGRITY */ 809 810 /* 811 * Mark a bio as polled. Note that for async polled IO, the caller must 812 * expect -EWOULDBLOCK if we cannot allocate a request (or other resources). 813 * We cannot block waiting for requests on polled IO, as those completions 814 * must be found by the caller. This is different than IRQ driven IO, where 815 * it's safe to wait for IO to complete. 816 */ 817 static inline void bio_set_polled(struct bio *bio, struct kiocb *kiocb) 818 { 819 bio->bi_opf |= REQ_HIPRI; 820 if (!is_sync_kiocb(kiocb)) 821 bio->bi_opf |= REQ_NOWAIT; 822 } 823 824 #endif /* CONFIG_BLOCK */ 825 #endif /* __LINUX_BIO_H */ 826