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 /* struct bio, bio_vec and BIO_* flags are defined in blk_types.h */ 12 #include <linux/blk_types.h> 13 #include <linux/uio.h> 14 15 #define BIO_DEBUG 16 17 #ifdef BIO_DEBUG 18 #define BIO_BUG_ON BUG_ON 19 #else 20 #define BIO_BUG_ON 21 #endif 22 23 #define BIO_MAX_VECS 256U 24 25 static inline unsigned int bio_max_segs(unsigned int nr_segs) 26 { 27 return min(nr_segs, BIO_MAX_VECS); 28 } 29 30 #define bio_prio(bio) (bio)->bi_ioprio 31 #define bio_set_prio(bio, prio) ((bio)->bi_ioprio = prio) 32 33 #define bio_iter_iovec(bio, iter) \ 34 bvec_iter_bvec((bio)->bi_io_vec, (iter)) 35 36 #define bio_iter_page(bio, iter) \ 37 bvec_iter_page((bio)->bi_io_vec, (iter)) 38 #define bio_iter_len(bio, iter) \ 39 bvec_iter_len((bio)->bi_io_vec, (iter)) 40 #define bio_iter_offset(bio, iter) \ 41 bvec_iter_offset((bio)->bi_io_vec, (iter)) 42 43 #define bio_page(bio) bio_iter_page((bio), (bio)->bi_iter) 44 #define bio_offset(bio) bio_iter_offset((bio), (bio)->bi_iter) 45 #define bio_iovec(bio) bio_iter_iovec((bio), (bio)->bi_iter) 46 47 #define bio_multiple_segments(bio) \ 48 ((bio)->bi_iter.bi_size != bio_iovec(bio).bv_len) 49 50 #define bvec_iter_sectors(iter) ((iter).bi_size >> 9) 51 #define bvec_iter_end_sector(iter) ((iter).bi_sector + bvec_iter_sectors((iter))) 52 53 #define bio_sectors(bio) bvec_iter_sectors((bio)->bi_iter) 54 #define bio_end_sector(bio) bvec_iter_end_sector((bio)->bi_iter) 55 56 /* 57 * Return the data direction, READ or WRITE. 58 */ 59 #define bio_data_dir(bio) \ 60 (op_is_write(bio_op(bio)) ? WRITE : READ) 61 62 /* 63 * Check whether this bio carries any data or not. A NULL bio is allowed. 64 */ 65 static inline bool bio_has_data(struct bio *bio) 66 { 67 if (bio && 68 bio->bi_iter.bi_size && 69 bio_op(bio) != REQ_OP_DISCARD && 70 bio_op(bio) != REQ_OP_SECURE_ERASE && 71 bio_op(bio) != REQ_OP_WRITE_ZEROES) 72 return true; 73 74 return false; 75 } 76 77 static inline bool bio_no_advance_iter(const struct bio *bio) 78 { 79 return bio_op(bio) == REQ_OP_DISCARD || 80 bio_op(bio) == REQ_OP_SECURE_ERASE || 81 bio_op(bio) == REQ_OP_WRITE_SAME || 82 bio_op(bio) == REQ_OP_WRITE_ZEROES; 83 } 84 85 static inline bool bio_mergeable(struct bio *bio) 86 { 87 if (bio->bi_opf & REQ_NOMERGE_FLAGS) 88 return false; 89 90 return true; 91 } 92 93 static inline unsigned int bio_cur_bytes(struct bio *bio) 94 { 95 if (bio_has_data(bio)) 96 return bio_iovec(bio).bv_len; 97 else /* dataless requests such as discard */ 98 return bio->bi_iter.bi_size; 99 } 100 101 static inline void *bio_data(struct bio *bio) 102 { 103 if (bio_has_data(bio)) 104 return page_address(bio_page(bio)) + bio_offset(bio); 105 106 return NULL; 107 } 108 109 /** 110 * bio_full - check if the bio is full 111 * @bio: bio to check 112 * @len: length of one segment to be added 113 * 114 * Return true if @bio is full and one segment with @len bytes can't be 115 * added to the bio, otherwise return false 116 */ 117 static inline bool bio_full(struct bio *bio, unsigned len) 118 { 119 if (bio->bi_vcnt >= bio->bi_max_vecs) 120 return true; 121 122 if (bio->bi_iter.bi_size > UINT_MAX - len) 123 return true; 124 125 return false; 126 } 127 128 static inline bool bio_next_segment(const struct bio *bio, 129 struct bvec_iter_all *iter) 130 { 131 if (iter->idx >= bio->bi_vcnt) 132 return false; 133 134 bvec_advance(&bio->bi_io_vec[iter->idx], iter); 135 return true; 136 } 137 138 /* 139 * drivers should _never_ use the all version - the bio may have been split 140 * before it got to the driver and the driver won't own all of it 141 */ 142 #define bio_for_each_segment_all(bvl, bio, iter) \ 143 for (bvl = bvec_init_iter_all(&iter); bio_next_segment((bio), &iter); ) 144 145 static inline void bio_advance_iter(const struct bio *bio, 146 struct bvec_iter *iter, unsigned int bytes) 147 { 148 iter->bi_sector += bytes >> 9; 149 150 if (bio_no_advance_iter(bio)) 151 iter->bi_size -= bytes; 152 else 153 bvec_iter_advance(bio->bi_io_vec, iter, bytes); 154 /* TODO: It is reasonable to complete bio with error here. */ 155 } 156 157 /* @bytes should be less or equal to bvec[i->bi_idx].bv_len */ 158 static inline void bio_advance_iter_single(const struct bio *bio, 159 struct bvec_iter *iter, 160 unsigned int bytes) 161 { 162 iter->bi_sector += bytes >> 9; 163 164 if (bio_no_advance_iter(bio)) 165 iter->bi_size -= bytes; 166 else 167 bvec_iter_advance_single(bio->bi_io_vec, iter, bytes); 168 } 169 170 #define __bio_for_each_segment(bvl, bio, iter, start) \ 171 for (iter = (start); \ 172 (iter).bi_size && \ 173 ((bvl = bio_iter_iovec((bio), (iter))), 1); \ 174 bio_advance_iter_single((bio), &(iter), (bvl).bv_len)) 175 176 #define bio_for_each_segment(bvl, bio, iter) \ 177 __bio_for_each_segment(bvl, bio, iter, (bio)->bi_iter) 178 179 #define __bio_for_each_bvec(bvl, bio, iter, start) \ 180 for (iter = (start); \ 181 (iter).bi_size && \ 182 ((bvl = mp_bvec_iter_bvec((bio)->bi_io_vec, (iter))), 1); \ 183 bio_advance_iter_single((bio), &(iter), (bvl).bv_len)) 184 185 /* iterate over multi-page bvec */ 186 #define bio_for_each_bvec(bvl, bio, iter) \ 187 __bio_for_each_bvec(bvl, bio, iter, (bio)->bi_iter) 188 189 /* 190 * Iterate over all multi-page bvecs. Drivers shouldn't use this version for the 191 * same reasons as bio_for_each_segment_all(). 192 */ 193 #define bio_for_each_bvec_all(bvl, bio, i) \ 194 for (i = 0, bvl = bio_first_bvec_all(bio); \ 195 i < (bio)->bi_vcnt; i++, bvl++) \ 196 197 #define bio_iter_last(bvec, iter) ((iter).bi_size == (bvec).bv_len) 198 199 static inline unsigned bio_segments(struct bio *bio) 200 { 201 unsigned segs = 0; 202 struct bio_vec bv; 203 struct bvec_iter iter; 204 205 /* 206 * We special case discard/write same/write zeroes, because they 207 * interpret bi_size differently: 208 */ 209 210 switch (bio_op(bio)) { 211 case REQ_OP_DISCARD: 212 case REQ_OP_SECURE_ERASE: 213 case REQ_OP_WRITE_ZEROES: 214 return 0; 215 case REQ_OP_WRITE_SAME: 216 return 1; 217 default: 218 break; 219 } 220 221 bio_for_each_segment(bv, bio, iter) 222 segs++; 223 224 return segs; 225 } 226 227 /* 228 * get a reference to a bio, so it won't disappear. the intended use is 229 * something like: 230 * 231 * bio_get(bio); 232 * submit_bio(rw, bio); 233 * if (bio->bi_flags ...) 234 * do_something 235 * bio_put(bio); 236 * 237 * without the bio_get(), it could potentially complete I/O before submit_bio 238 * returns. and then bio would be freed memory when if (bio->bi_flags ...) 239 * runs 240 */ 241 static inline void bio_get(struct bio *bio) 242 { 243 bio->bi_flags |= (1 << BIO_REFFED); 244 smp_mb__before_atomic(); 245 atomic_inc(&bio->__bi_cnt); 246 } 247 248 static inline void bio_cnt_set(struct bio *bio, unsigned int count) 249 { 250 if (count != 1) { 251 bio->bi_flags |= (1 << BIO_REFFED); 252 smp_mb(); 253 } 254 atomic_set(&bio->__bi_cnt, count); 255 } 256 257 static inline bool bio_flagged(struct bio *bio, unsigned int bit) 258 { 259 return (bio->bi_flags & (1U << bit)) != 0; 260 } 261 262 static inline void bio_set_flag(struct bio *bio, unsigned int bit) 263 { 264 bio->bi_flags |= (1U << bit); 265 } 266 267 static inline void bio_clear_flag(struct bio *bio, unsigned int bit) 268 { 269 bio->bi_flags &= ~(1U << bit); 270 } 271 272 static inline void bio_get_first_bvec(struct bio *bio, struct bio_vec *bv) 273 { 274 *bv = bio_iovec(bio); 275 } 276 277 static inline void bio_get_last_bvec(struct bio *bio, struct bio_vec *bv) 278 { 279 struct bvec_iter iter = bio->bi_iter; 280 int idx; 281 282 if (unlikely(!bio_multiple_segments(bio))) { 283 *bv = bio_iovec(bio); 284 return; 285 } 286 287 bio_advance_iter(bio, &iter, iter.bi_size); 288 289 if (!iter.bi_bvec_done) 290 idx = iter.bi_idx - 1; 291 else /* in the middle of bvec */ 292 idx = iter.bi_idx; 293 294 *bv = bio->bi_io_vec[idx]; 295 296 /* 297 * iter.bi_bvec_done records actual length of the last bvec 298 * if this bio ends in the middle of one io vector 299 */ 300 if (iter.bi_bvec_done) 301 bv->bv_len = iter.bi_bvec_done; 302 } 303 304 static inline struct bio_vec *bio_first_bvec_all(struct bio *bio) 305 { 306 WARN_ON_ONCE(bio_flagged(bio, BIO_CLONED)); 307 return bio->bi_io_vec; 308 } 309 310 static inline struct page *bio_first_page_all(struct bio *bio) 311 { 312 return bio_first_bvec_all(bio)->bv_page; 313 } 314 315 static inline struct bio_vec *bio_last_bvec_all(struct bio *bio) 316 { 317 WARN_ON_ONCE(bio_flagged(bio, BIO_CLONED)); 318 return &bio->bi_io_vec[bio->bi_vcnt - 1]; 319 } 320 321 enum bip_flags { 322 BIP_BLOCK_INTEGRITY = 1 << 0, /* block layer owns integrity data */ 323 BIP_MAPPED_INTEGRITY = 1 << 1, /* ref tag has been remapped */ 324 BIP_CTRL_NOCHECK = 1 << 2, /* disable HBA integrity checking */ 325 BIP_DISK_NOCHECK = 1 << 3, /* disable disk integrity checking */ 326 BIP_IP_CHECKSUM = 1 << 4, /* IP checksum */ 327 }; 328 329 /* 330 * bio integrity payload 331 */ 332 struct bio_integrity_payload { 333 struct bio *bip_bio; /* parent bio */ 334 335 struct bvec_iter bip_iter; 336 337 unsigned short bip_vcnt; /* # of integrity bio_vecs */ 338 unsigned short bip_max_vcnt; /* integrity bio_vec slots */ 339 unsigned short bip_flags; /* control flags */ 340 341 struct bvec_iter bio_iter; /* for rewinding parent bio */ 342 343 struct work_struct bip_work; /* I/O completion */ 344 345 struct bio_vec *bip_vec; 346 struct bio_vec bip_inline_vecs[];/* embedded bvec array */ 347 }; 348 349 #if defined(CONFIG_BLK_DEV_INTEGRITY) 350 351 static inline struct bio_integrity_payload *bio_integrity(struct bio *bio) 352 { 353 if (bio->bi_opf & REQ_INTEGRITY) 354 return bio->bi_integrity; 355 356 return NULL; 357 } 358 359 static inline bool bio_integrity_flagged(struct bio *bio, enum bip_flags flag) 360 { 361 struct bio_integrity_payload *bip = bio_integrity(bio); 362 363 if (bip) 364 return bip->bip_flags & flag; 365 366 return false; 367 } 368 369 static inline sector_t bip_get_seed(struct bio_integrity_payload *bip) 370 { 371 return bip->bip_iter.bi_sector; 372 } 373 374 static inline void bip_set_seed(struct bio_integrity_payload *bip, 375 sector_t seed) 376 { 377 bip->bip_iter.bi_sector = seed; 378 } 379 380 #endif /* CONFIG_BLK_DEV_INTEGRITY */ 381 382 extern void bio_trim(struct bio *bio, int offset, int size); 383 extern struct bio *bio_split(struct bio *bio, int sectors, 384 gfp_t gfp, struct bio_set *bs); 385 386 /** 387 * bio_next_split - get next @sectors from a bio, splitting if necessary 388 * @bio: bio to split 389 * @sectors: number of sectors to split from the front of @bio 390 * @gfp: gfp mask 391 * @bs: bio set to allocate from 392 * 393 * Returns a bio representing the next @sectors of @bio - if the bio is smaller 394 * than @sectors, returns the original bio unchanged. 395 */ 396 static inline struct bio *bio_next_split(struct bio *bio, int sectors, 397 gfp_t gfp, struct bio_set *bs) 398 { 399 if (sectors >= bio_sectors(bio)) 400 return bio; 401 402 return bio_split(bio, sectors, gfp, bs); 403 } 404 405 enum { 406 BIOSET_NEED_BVECS = BIT(0), 407 BIOSET_NEED_RESCUER = BIT(1), 408 }; 409 extern int bioset_init(struct bio_set *, unsigned int, unsigned int, int flags); 410 extern void bioset_exit(struct bio_set *); 411 extern int biovec_init_pool(mempool_t *pool, int pool_entries); 412 extern int bioset_init_from_src(struct bio_set *bs, struct bio_set *src); 413 414 struct bio *bio_alloc_bioset(gfp_t gfp, unsigned short nr_iovecs, 415 struct bio_set *bs); 416 struct bio *bio_kmalloc(gfp_t gfp_mask, unsigned short nr_iovecs); 417 extern void bio_put(struct bio *); 418 419 extern void __bio_clone_fast(struct bio *, struct bio *); 420 extern struct bio *bio_clone_fast(struct bio *, gfp_t, struct bio_set *); 421 422 extern struct bio_set fs_bio_set; 423 424 static inline struct bio *bio_alloc(gfp_t gfp_mask, unsigned short nr_iovecs) 425 { 426 return bio_alloc_bioset(gfp_mask, nr_iovecs, &fs_bio_set); 427 } 428 429 extern blk_qc_t submit_bio(struct bio *); 430 431 extern void bio_endio(struct bio *); 432 433 static inline void bio_io_error(struct bio *bio) 434 { 435 bio->bi_status = BLK_STS_IOERR; 436 bio_endio(bio); 437 } 438 439 static inline void bio_wouldblock_error(struct bio *bio) 440 { 441 bio_set_flag(bio, BIO_QUIET); 442 bio->bi_status = BLK_STS_AGAIN; 443 bio_endio(bio); 444 } 445 446 /* 447 * Calculate number of bvec segments that should be allocated to fit data 448 * pointed by @iter. If @iter is backed by bvec it's going to be reused 449 * instead of allocating a new one. 450 */ 451 static inline int bio_iov_vecs_to_alloc(struct iov_iter *iter, int max_segs) 452 { 453 if (iov_iter_is_bvec(iter)) 454 return 0; 455 return iov_iter_npages(iter, max_segs); 456 } 457 458 struct request_queue; 459 460 extern int submit_bio_wait(struct bio *bio); 461 extern void bio_advance(struct bio *, unsigned); 462 463 extern void bio_init(struct bio *bio, struct bio_vec *table, 464 unsigned short max_vecs); 465 extern void bio_uninit(struct bio *); 466 extern void bio_reset(struct bio *); 467 void bio_chain(struct bio *, struct bio *); 468 469 extern int bio_add_page(struct bio *, struct page *, unsigned int,unsigned int); 470 extern int bio_add_pc_page(struct request_queue *, struct bio *, struct page *, 471 unsigned int, unsigned int); 472 int bio_add_zone_append_page(struct bio *bio, struct page *page, 473 unsigned int len, unsigned int offset); 474 bool __bio_try_merge_page(struct bio *bio, struct page *page, 475 unsigned int len, unsigned int off, bool *same_page); 476 void __bio_add_page(struct bio *bio, struct page *page, 477 unsigned int len, unsigned int off); 478 int bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter); 479 void bio_release_pages(struct bio *bio, bool mark_dirty); 480 extern void bio_set_pages_dirty(struct bio *bio); 481 extern void bio_check_pages_dirty(struct bio *bio); 482 483 extern void bio_copy_data_iter(struct bio *dst, struct bvec_iter *dst_iter, 484 struct bio *src, struct bvec_iter *src_iter); 485 extern void bio_copy_data(struct bio *dst, struct bio *src); 486 extern void bio_list_copy_data(struct bio *dst, struct bio *src); 487 extern void bio_free_pages(struct bio *bio); 488 void zero_fill_bio_iter(struct bio *bio, struct bvec_iter iter); 489 void bio_truncate(struct bio *bio, unsigned new_size); 490 void guard_bio_eod(struct bio *bio); 491 492 static inline void zero_fill_bio(struct bio *bio) 493 { 494 zero_fill_bio_iter(bio, bio->bi_iter); 495 } 496 497 extern const char *bio_devname(struct bio *bio, char *buffer); 498 499 #define bio_set_dev(bio, bdev) \ 500 do { \ 501 bio_clear_flag(bio, BIO_REMAPPED); \ 502 if ((bio)->bi_bdev != (bdev)) \ 503 bio_clear_flag(bio, BIO_THROTTLED); \ 504 (bio)->bi_bdev = (bdev); \ 505 bio_associate_blkg(bio); \ 506 } while (0) 507 508 #define bio_copy_dev(dst, src) \ 509 do { \ 510 bio_clear_flag(dst, BIO_REMAPPED); \ 511 (dst)->bi_bdev = (src)->bi_bdev; \ 512 bio_clone_blkg_association(dst, src); \ 513 } while (0) 514 515 #define bio_dev(bio) \ 516 disk_devt((bio)->bi_bdev->bd_disk) 517 518 #ifdef CONFIG_BLK_CGROUP 519 void bio_associate_blkg(struct bio *bio); 520 void bio_associate_blkg_from_css(struct bio *bio, 521 struct cgroup_subsys_state *css); 522 void bio_clone_blkg_association(struct bio *dst, struct bio *src); 523 #else /* CONFIG_BLK_CGROUP */ 524 static inline void bio_associate_blkg(struct bio *bio) { } 525 static inline void bio_associate_blkg_from_css(struct bio *bio, 526 struct cgroup_subsys_state *css) 527 { } 528 static inline void bio_clone_blkg_association(struct bio *dst, 529 struct bio *src) { } 530 #endif /* CONFIG_BLK_CGROUP */ 531 532 #ifdef CONFIG_HIGHMEM 533 /* 534 * remember never ever reenable interrupts between a bvec_kmap_irq and 535 * bvec_kunmap_irq! 536 */ 537 static inline char *bvec_kmap_irq(struct bio_vec *bvec, unsigned long *flags) 538 { 539 unsigned long addr; 540 541 /* 542 * might not be a highmem page, but the preempt/irq count 543 * balancing is a lot nicer this way 544 */ 545 local_irq_save(*flags); 546 addr = (unsigned long) kmap_atomic(bvec->bv_page); 547 548 BUG_ON(addr & ~PAGE_MASK); 549 550 return (char *) addr + bvec->bv_offset; 551 } 552 553 static inline void bvec_kunmap_irq(char *buffer, unsigned long *flags) 554 { 555 unsigned long ptr = (unsigned long) buffer & PAGE_MASK; 556 557 kunmap_atomic((void *) ptr); 558 local_irq_restore(*flags); 559 } 560 561 #else 562 static inline char *bvec_kmap_irq(struct bio_vec *bvec, unsigned long *flags) 563 { 564 return page_address(bvec->bv_page) + bvec->bv_offset; 565 } 566 567 static inline void bvec_kunmap_irq(char *buffer, unsigned long *flags) 568 { 569 *flags = 0; 570 } 571 #endif 572 573 /* 574 * BIO list management for use by remapping drivers (e.g. DM or MD) and loop. 575 * 576 * A bio_list anchors a singly-linked list of bios chained through the bi_next 577 * member of the bio. The bio_list also caches the last list member to allow 578 * fast access to the tail. 579 */ 580 struct bio_list { 581 struct bio *head; 582 struct bio *tail; 583 }; 584 585 static inline int bio_list_empty(const struct bio_list *bl) 586 { 587 return bl->head == NULL; 588 } 589 590 static inline void bio_list_init(struct bio_list *bl) 591 { 592 bl->head = bl->tail = NULL; 593 } 594 595 #define BIO_EMPTY_LIST { NULL, NULL } 596 597 #define bio_list_for_each(bio, bl) \ 598 for (bio = (bl)->head; bio; bio = bio->bi_next) 599 600 static inline unsigned bio_list_size(const struct bio_list *bl) 601 { 602 unsigned sz = 0; 603 struct bio *bio; 604 605 bio_list_for_each(bio, bl) 606 sz++; 607 608 return sz; 609 } 610 611 static inline void bio_list_add(struct bio_list *bl, struct bio *bio) 612 { 613 bio->bi_next = NULL; 614 615 if (bl->tail) 616 bl->tail->bi_next = bio; 617 else 618 bl->head = bio; 619 620 bl->tail = bio; 621 } 622 623 static inline void bio_list_add_head(struct bio_list *bl, struct bio *bio) 624 { 625 bio->bi_next = bl->head; 626 627 bl->head = bio; 628 629 if (!bl->tail) 630 bl->tail = bio; 631 } 632 633 static inline void bio_list_merge(struct bio_list *bl, struct bio_list *bl2) 634 { 635 if (!bl2->head) 636 return; 637 638 if (bl->tail) 639 bl->tail->bi_next = bl2->head; 640 else 641 bl->head = bl2->head; 642 643 bl->tail = bl2->tail; 644 } 645 646 static inline void bio_list_merge_head(struct bio_list *bl, 647 struct bio_list *bl2) 648 { 649 if (!bl2->head) 650 return; 651 652 if (bl->head) 653 bl2->tail->bi_next = bl->head; 654 else 655 bl->tail = bl2->tail; 656 657 bl->head = bl2->head; 658 } 659 660 static inline struct bio *bio_list_peek(struct bio_list *bl) 661 { 662 return bl->head; 663 } 664 665 static inline struct bio *bio_list_pop(struct bio_list *bl) 666 { 667 struct bio *bio = bl->head; 668 669 if (bio) { 670 bl->head = bl->head->bi_next; 671 if (!bl->head) 672 bl->tail = NULL; 673 674 bio->bi_next = NULL; 675 } 676 677 return bio; 678 } 679 680 static inline struct bio *bio_list_get(struct bio_list *bl) 681 { 682 struct bio *bio = bl->head; 683 684 bl->head = bl->tail = NULL; 685 686 return bio; 687 } 688 689 /* 690 * Increment chain count for the bio. Make sure the CHAIN flag update 691 * is visible before the raised count. 692 */ 693 static inline void bio_inc_remaining(struct bio *bio) 694 { 695 bio_set_flag(bio, BIO_CHAIN); 696 smp_mb__before_atomic(); 697 atomic_inc(&bio->__bi_remaining); 698 } 699 700 /* 701 * bio_set is used to allow other portions of the IO system to 702 * allocate their own private memory pools for bio and iovec structures. 703 * These memory pools in turn all allocate from the bio_slab 704 * and the bvec_slabs[]. 705 */ 706 #define BIO_POOL_SIZE 2 707 708 struct bio_set { 709 struct kmem_cache *bio_slab; 710 unsigned int front_pad; 711 712 mempool_t bio_pool; 713 mempool_t bvec_pool; 714 #if defined(CONFIG_BLK_DEV_INTEGRITY) 715 mempool_t bio_integrity_pool; 716 mempool_t bvec_integrity_pool; 717 #endif 718 719 unsigned int back_pad; 720 /* 721 * Deadlock avoidance for stacking block drivers: see comments in 722 * bio_alloc_bioset() for details 723 */ 724 spinlock_t rescue_lock; 725 struct bio_list rescue_list; 726 struct work_struct rescue_work; 727 struct workqueue_struct *rescue_workqueue; 728 }; 729 730 static inline bool bioset_initialized(struct bio_set *bs) 731 { 732 return bs->bio_slab != NULL; 733 } 734 735 #if defined(CONFIG_BLK_DEV_INTEGRITY) 736 737 #define bip_for_each_vec(bvl, bip, iter) \ 738 for_each_bvec(bvl, (bip)->bip_vec, iter, (bip)->bip_iter) 739 740 #define bio_for_each_integrity_vec(_bvl, _bio, _iter) \ 741 for_each_bio(_bio) \ 742 bip_for_each_vec(_bvl, _bio->bi_integrity, _iter) 743 744 extern struct bio_integrity_payload *bio_integrity_alloc(struct bio *, gfp_t, unsigned int); 745 extern int bio_integrity_add_page(struct bio *, struct page *, unsigned int, unsigned int); 746 extern bool bio_integrity_prep(struct bio *); 747 extern void bio_integrity_advance(struct bio *, unsigned int); 748 extern void bio_integrity_trim(struct bio *); 749 extern int bio_integrity_clone(struct bio *, struct bio *, gfp_t); 750 extern int bioset_integrity_create(struct bio_set *, int); 751 extern void bioset_integrity_free(struct bio_set *); 752 extern void bio_integrity_init(void); 753 754 #else /* CONFIG_BLK_DEV_INTEGRITY */ 755 756 static inline void *bio_integrity(struct bio *bio) 757 { 758 return NULL; 759 } 760 761 static inline int bioset_integrity_create(struct bio_set *bs, int pool_size) 762 { 763 return 0; 764 } 765 766 static inline void bioset_integrity_free (struct bio_set *bs) 767 { 768 return; 769 } 770 771 static inline bool bio_integrity_prep(struct bio *bio) 772 { 773 return true; 774 } 775 776 static inline int bio_integrity_clone(struct bio *bio, struct bio *bio_src, 777 gfp_t gfp_mask) 778 { 779 return 0; 780 } 781 782 static inline void bio_integrity_advance(struct bio *bio, 783 unsigned int bytes_done) 784 { 785 return; 786 } 787 788 static inline void bio_integrity_trim(struct bio *bio) 789 { 790 return; 791 } 792 793 static inline void bio_integrity_init(void) 794 { 795 return; 796 } 797 798 static inline bool bio_integrity_flagged(struct bio *bio, enum bip_flags flag) 799 { 800 return false; 801 } 802 803 static inline void *bio_integrity_alloc(struct bio * bio, gfp_t gfp, 804 unsigned int nr) 805 { 806 return ERR_PTR(-EINVAL); 807 } 808 809 static inline int bio_integrity_add_page(struct bio *bio, struct page *page, 810 unsigned int len, unsigned int offset) 811 { 812 return 0; 813 } 814 815 #endif /* CONFIG_BLK_DEV_INTEGRITY */ 816 817 /* 818 * Mark a bio as polled. Note that for async polled IO, the caller must 819 * expect -EWOULDBLOCK if we cannot allocate a request (or other resources). 820 * We cannot block waiting for requests on polled IO, as those completions 821 * must be found by the caller. This is different than IRQ driven IO, where 822 * it's safe to wait for IO to complete. 823 */ 824 static inline void bio_set_polled(struct bio *bio, struct kiocb *kiocb) 825 { 826 bio->bi_opf |= REQ_HIPRI; 827 if (!is_sync_kiocb(kiocb)) 828 bio->bi_opf |= REQ_NOWAIT; 829 } 830 831 #endif /* __LINUX_BIO_H */ 832