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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 */ 61static 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 73static 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 81static 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 89static 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 97static 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 105static inline bool bio_full(struct bio *bio) 106{ 107 return bio->bi_vcnt >= bio->bi_max_vecs; 108} 109 110static inline bool bio_next_segment(const struct bio *bio, 111 struct bvec_iter_all *iter) 112{ 113 if (iter->idx >= bio->bi_vcnt) 114 return false; 115 116 bvec_advance(&bio->bi_io_vec[iter->idx], iter); 117 return true; 118} 119 120/* 121 * drivers should _never_ use the all version - the bio may have been split 122 * before it got to the driver and the driver won't own all of it 123 */ 124#define bio_for_each_segment_all(bvl, bio, iter) \ 125 for (bvl = bvec_init_iter_all(&iter); bio_next_segment((bio), &iter); ) 126 127static inline void bio_advance_iter(struct bio *bio, struct bvec_iter *iter, 128 unsigned bytes) 129{ 130 iter->bi_sector += bytes >> 9; 131 132 if (bio_no_advance_iter(bio)) 133 iter->bi_size -= bytes; 134 else 135 bvec_iter_advance(bio->bi_io_vec, iter, bytes); 136 /* TODO: It is reasonable to complete bio with error here. */ 137} 138 139#define __bio_for_each_segment(bvl, bio, iter, start) \ 140 for (iter = (start); \ 141 (iter).bi_size && \ 142 ((bvl = bio_iter_iovec((bio), (iter))), 1); \ 143 bio_advance_iter((bio), &(iter), (bvl).bv_len)) 144 145#define bio_for_each_segment(bvl, bio, iter) \ 146 __bio_for_each_segment(bvl, bio, iter, (bio)->bi_iter) 147 148#define __bio_for_each_bvec(bvl, bio, iter, start) \ 149 for (iter = (start); \ 150 (iter).bi_size && \ 151 ((bvl = mp_bvec_iter_bvec((bio)->bi_io_vec, (iter))), 1); \ 152 bio_advance_iter((bio), &(iter), (bvl).bv_len)) 153 154/* iterate over multi-page bvec */ 155#define bio_for_each_bvec(bvl, bio, iter) \ 156 __bio_for_each_bvec(bvl, bio, iter, (bio)->bi_iter) 157 158#define bio_iter_last(bvec, iter) ((iter).bi_size == (bvec).bv_len) 159 160static inline unsigned bio_segments(struct bio *bio) 161{ 162 unsigned segs = 0; 163 struct bio_vec bv; 164 struct bvec_iter iter; 165 166 /* 167 * We special case discard/write same/write zeroes, because they 168 * interpret bi_size differently: 169 */ 170 171 switch (bio_op(bio)) { 172 case REQ_OP_DISCARD: 173 case REQ_OP_SECURE_ERASE: 174 case REQ_OP_WRITE_ZEROES: 175 return 0; 176 case REQ_OP_WRITE_SAME: 177 return 1; 178 default: 179 break; 180 } 181 182 bio_for_each_segment(bv, bio, iter) 183 segs++; 184 185 return segs; 186} 187 188/* 189 * get a reference to a bio, so it won't disappear. the intended use is 190 * something like: 191 * 192 * bio_get(bio); 193 * submit_bio(rw, bio); 194 * if (bio->bi_flags ...) 195 * do_something 196 * bio_put(bio); 197 * 198 * without the bio_get(), it could potentially complete I/O before submit_bio 199 * returns. and then bio would be freed memory when if (bio->bi_flags ...) 200 * runs 201 */ 202static inline void bio_get(struct bio *bio) 203{ 204 bio->bi_flags |= (1 << BIO_REFFED); 205 smp_mb__before_atomic(); 206 atomic_inc(&bio->__bi_cnt); 207} 208 209static inline void bio_cnt_set(struct bio *bio, unsigned int count) 210{ 211 if (count != 1) { 212 bio->bi_flags |= (1 << BIO_REFFED); 213 smp_mb(); 214 } 215 atomic_set(&bio->__bi_cnt, count); 216} 217 218static inline bool bio_flagged(struct bio *bio, unsigned int bit) 219{ 220 return (bio->bi_flags & (1U << bit)) != 0; 221} 222 223static inline void bio_set_flag(struct bio *bio, unsigned int bit) 224{ 225 bio->bi_flags |= (1U << bit); 226} 227 228static inline void bio_clear_flag(struct bio *bio, unsigned int bit) 229{ 230 bio->bi_flags &= ~(1U << bit); 231} 232 233static inline void bio_get_first_bvec(struct bio *bio, struct bio_vec *bv) 234{ 235 *bv = bio_iovec(bio); 236} 237 238static inline void bio_get_last_bvec(struct bio *bio, struct bio_vec *bv) 239{ 240 struct bvec_iter iter = bio->bi_iter; 241 int idx; 242 243 if (unlikely(!bio_multiple_segments(bio))) { 244 *bv = bio_iovec(bio); 245 return; 246 } 247 248 bio_advance_iter(bio, &iter, iter.bi_size); 249 250 if (!iter.bi_bvec_done) 251 idx = iter.bi_idx - 1; 252 else /* in the middle of bvec */ 253 idx = iter.bi_idx; 254 255 *bv = bio->bi_io_vec[idx]; 256 257 /* 258 * iter.bi_bvec_done records actual length of the last bvec 259 * if this bio ends in the middle of one io vector 260 */ 261 if (iter.bi_bvec_done) 262 bv->bv_len = iter.bi_bvec_done; 263} 264 265static inline struct bio_vec *bio_first_bvec_all(struct bio *bio) 266{ 267 WARN_ON_ONCE(bio_flagged(bio, BIO_CLONED)); 268 return bio->bi_io_vec; 269} 270 271static inline struct page *bio_first_page_all(struct bio *bio) 272{ 273 return bio_first_bvec_all(bio)->bv_page; 274} 275 276static inline struct bio_vec *bio_last_bvec_all(struct bio *bio) 277{ 278 WARN_ON_ONCE(bio_flagged(bio, BIO_CLONED)); 279 return &bio->bi_io_vec[bio->bi_vcnt - 1]; 280} 281 282enum bip_flags { 283 BIP_BLOCK_INTEGRITY = 1 << 0, /* block layer owns integrity data */ 284 BIP_MAPPED_INTEGRITY = 1 << 1, /* ref tag has been remapped */ 285 BIP_CTRL_NOCHECK = 1 << 2, /* disable HBA integrity checking */ 286 BIP_DISK_NOCHECK = 1 << 3, /* disable disk integrity checking */ 287 BIP_IP_CHECKSUM = 1 << 4, /* IP checksum */ 288}; 289 290/* 291 * bio integrity payload 292 */ 293struct bio_integrity_payload { 294 struct bio *bip_bio; /* parent bio */ 295 296 struct bvec_iter bip_iter; 297 298 unsigned short bip_slab; /* slab the bip came from */ 299 unsigned short bip_vcnt; /* # of integrity bio_vecs */ 300 unsigned short bip_max_vcnt; /* integrity bio_vec slots */ 301 unsigned short bip_flags; /* control flags */ 302 303 struct bvec_iter bio_iter; /* for rewinding parent bio */ 304 305 struct work_struct bip_work; /* I/O completion */ 306 307 struct bio_vec *bip_vec; 308 struct bio_vec bip_inline_vecs[0];/* embedded bvec array */ 309}; 310 311#if defined(CONFIG_BLK_DEV_INTEGRITY) 312 313static inline struct bio_integrity_payload *bio_integrity(struct bio *bio) 314{ 315 if (bio->bi_opf & REQ_INTEGRITY) 316 return bio->bi_integrity; 317 318 return NULL; 319} 320 321static inline bool bio_integrity_flagged(struct bio *bio, enum bip_flags flag) 322{ 323 struct bio_integrity_payload *bip = bio_integrity(bio); 324 325 if (bip) 326 return bip->bip_flags & flag; 327 328 return false; 329} 330 331static inline sector_t bip_get_seed(struct bio_integrity_payload *bip) 332{ 333 return bip->bip_iter.bi_sector; 334} 335 336static inline void bip_set_seed(struct bio_integrity_payload *bip, 337 sector_t seed) 338{ 339 bip->bip_iter.bi_sector = seed; 340} 341 342#endif /* CONFIG_BLK_DEV_INTEGRITY */ 343 344extern void bio_trim(struct bio *bio, int offset, int size); 345extern struct bio *bio_split(struct bio *bio, int sectors, 346 gfp_t gfp, struct bio_set *bs); 347 348/** 349 * bio_next_split - get next @sectors from a bio, splitting if necessary 350 * @bio: bio to split 351 * @sectors: number of sectors to split from the front of @bio 352 * @gfp: gfp mask 353 * @bs: bio set to allocate from 354 * 355 * Returns a bio representing the next @sectors of @bio - if the bio is smaller 356 * than @sectors, returns the original bio unchanged. 357 */ 358static inline struct bio *bio_next_split(struct bio *bio, int sectors, 359 gfp_t gfp, struct bio_set *bs) 360{ 361 if (sectors >= bio_sectors(bio)) 362 return bio; 363 364 return bio_split(bio, sectors, gfp, bs); 365} 366 367enum { 368 BIOSET_NEED_BVECS = BIT(0), 369 BIOSET_NEED_RESCUER = BIT(1), 370}; 371extern int bioset_init(struct bio_set *, unsigned int, unsigned int, int flags); 372extern void bioset_exit(struct bio_set *); 373extern int biovec_init_pool(mempool_t *pool, int pool_entries); 374extern int bioset_init_from_src(struct bio_set *bs, struct bio_set *src); 375 376extern struct bio *bio_alloc_bioset(gfp_t, unsigned int, struct bio_set *); 377extern void bio_put(struct bio *); 378 379extern void __bio_clone_fast(struct bio *, struct bio *); 380extern struct bio *bio_clone_fast(struct bio *, gfp_t, struct bio_set *); 381 382extern struct bio_set fs_bio_set; 383 384static inline struct bio *bio_alloc(gfp_t gfp_mask, unsigned int nr_iovecs) 385{ 386 return bio_alloc_bioset(gfp_mask, nr_iovecs, &fs_bio_set); 387} 388 389static inline struct bio *bio_kmalloc(gfp_t gfp_mask, unsigned int nr_iovecs) 390{ 391 return bio_alloc_bioset(gfp_mask, nr_iovecs, NULL); 392} 393 394extern blk_qc_t submit_bio(struct bio *); 395 396extern void bio_endio(struct bio *); 397 398static inline void bio_io_error(struct bio *bio) 399{ 400 bio->bi_status = BLK_STS_IOERR; 401 bio_endio(bio); 402} 403 404static inline void bio_wouldblock_error(struct bio *bio) 405{ 406 bio->bi_status = BLK_STS_AGAIN; 407 bio_endio(bio); 408} 409 410struct request_queue; 411extern int bio_phys_segments(struct request_queue *, struct bio *); 412 413extern int submit_bio_wait(struct bio *bio); 414extern void bio_advance(struct bio *, unsigned); 415 416extern void bio_init(struct bio *bio, struct bio_vec *table, 417 unsigned short max_vecs); 418extern void bio_uninit(struct bio *); 419extern void bio_reset(struct bio *); 420void bio_chain(struct bio *, struct bio *); 421 422extern int bio_add_page(struct bio *, struct page *, unsigned int,unsigned int); 423extern int bio_add_pc_page(struct request_queue *, struct bio *, struct page *, 424 unsigned int, unsigned int); 425bool __bio_try_merge_page(struct bio *bio, struct page *page, 426 unsigned int len, unsigned int off, bool *same_page); 427void __bio_add_page(struct bio *bio, struct page *page, 428 unsigned int len, unsigned int off); 429int bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter); 430struct rq_map_data; 431extern struct bio *bio_map_user_iov(struct request_queue *, 432 struct iov_iter *, gfp_t); 433extern void bio_unmap_user(struct bio *); 434extern struct bio *bio_map_kern(struct request_queue *, void *, unsigned int, 435 gfp_t); 436extern struct bio *bio_copy_kern(struct request_queue *, void *, unsigned int, 437 gfp_t, int); 438extern void bio_set_pages_dirty(struct bio *bio); 439extern void bio_check_pages_dirty(struct bio *bio); 440 441void generic_start_io_acct(struct request_queue *q, int op, 442 unsigned long sectors, struct hd_struct *part); 443void generic_end_io_acct(struct request_queue *q, int op, 444 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_iter(struct bio *dst, struct bvec_iter *dst_iter, 459 struct bio *src, struct bvec_iter *src_iter); 460extern void bio_copy_data(struct bio *dst, struct bio *src); 461extern void bio_list_copy_data(struct bio *dst, struct bio *src); 462extern void bio_free_pages(struct bio *bio); 463 464extern struct bio *bio_copy_user_iov(struct request_queue *, 465 struct rq_map_data *, 466 struct iov_iter *, 467 gfp_t); 468extern int bio_uncopy_user(struct bio *); 469void zero_fill_bio_iter(struct bio *bio, struct bvec_iter iter); 470 471static inline void zero_fill_bio(struct bio *bio) 472{ 473 zero_fill_bio_iter(bio, bio->bi_iter); 474} 475 476extern struct bio_vec *bvec_alloc(gfp_t, int, unsigned long *, mempool_t *); 477extern void bvec_free(mempool_t *, struct bio_vec *, unsigned int); 478extern unsigned int bvec_nr_vecs(unsigned short idx); 479extern const char *bio_devname(struct bio *bio, char *buffer); 480 481#define bio_set_dev(bio, bdev) \ 482do { \ 483 if ((bio)->bi_disk != (bdev)->bd_disk) \ 484 bio_clear_flag(bio, BIO_THROTTLED);\ 485 (bio)->bi_disk = (bdev)->bd_disk; \ 486 (bio)->bi_partno = (bdev)->bd_partno; \ 487 bio_associate_blkg(bio); \ 488} while (0) 489 490#define bio_copy_dev(dst, src) \ 491do { \ 492 (dst)->bi_disk = (src)->bi_disk; \ 493 (dst)->bi_partno = (src)->bi_partno; \ 494 bio_clone_blkg_association(dst, src); \ 495} while (0) 496 497#define bio_dev(bio) \ 498 disk_devt((bio)->bi_disk) 499 500#if defined(CONFIG_MEMCG) && defined(CONFIG_BLK_CGROUP) 501void bio_associate_blkg_from_page(struct bio *bio, struct page *page); 502#else 503static inline void bio_associate_blkg_from_page(struct bio *bio, 504 struct page *page) { } 505#endif 506 507#ifdef CONFIG_BLK_CGROUP 508void bio_disassociate_blkg(struct bio *bio); 509void bio_associate_blkg(struct bio *bio); 510void bio_associate_blkg_from_css(struct bio *bio, 511 struct cgroup_subsys_state *css); 512void bio_clone_blkg_association(struct bio *dst, struct bio *src); 513#else /* CONFIG_BLK_CGROUP */ 514static inline void bio_disassociate_blkg(struct bio *bio) { } 515static inline void bio_associate_blkg(struct bio *bio) { } 516static inline void bio_associate_blkg_from_css(struct bio *bio, 517 struct cgroup_subsys_state *css) 518{ } 519static inline void bio_clone_blkg_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 */ 528static 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 544static 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 553static 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 558static 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 */ 571struct bio_list { 572 struct bio *head; 573 struct bio *tail; 574}; 575 576static inline int bio_list_empty(const struct bio_list *bl) 577{ 578 return bl->head == NULL; 579} 580 581static 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 591static 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 602static 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 614static 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 624static 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 637static 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 651static inline struct bio *bio_list_peek(struct bio_list *bl) 652{ 653 return bl->head; 654} 655 656static 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 671static 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 */ 684static 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 699struct 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 720struct biovec_slab { 721 int nr_vecs; 722 char *name; 723 struct kmem_cache *slab; 724}; 725 726static inline bool bioset_initialized(struct bio_set *bs) 727{ 728 return bs->bio_slab != NULL; 729} 730 731/* 732 * a small number of entries is fine, not going to be performance critical. 733 * basically we just need to survive 734 */ 735#define BIO_SPLIT_ENTRIES 2 736 737#if defined(CONFIG_BLK_DEV_INTEGRITY) 738 739#define bip_for_each_vec(bvl, bip, iter) \ 740 for_each_bvec(bvl, (bip)->bip_vec, iter, (bip)->bip_iter) 741 742#define bio_for_each_integrity_vec(_bvl, _bio, _iter) \ 743 for_each_bio(_bio) \ 744 bip_for_each_vec(_bvl, _bio->bi_integrity, _iter) 745 746extern struct bio_integrity_payload *bio_integrity_alloc(struct bio *, gfp_t, unsigned int); 747extern int bio_integrity_add_page(struct bio *, struct page *, unsigned int, unsigned int); 748extern bool bio_integrity_prep(struct bio *); 749extern void bio_integrity_advance(struct bio *, unsigned int); 750extern void bio_integrity_trim(struct bio *); 751extern int bio_integrity_clone(struct bio *, struct bio *, gfp_t); 752extern int bioset_integrity_create(struct bio_set *, int); 753extern void bioset_integrity_free(struct bio_set *); 754extern void bio_integrity_init(void); 755 756#else /* CONFIG_BLK_DEV_INTEGRITY */ 757 758static inline void *bio_integrity(struct bio *bio) 759{ 760 return NULL; 761} 762 763static inline int bioset_integrity_create(struct bio_set *bs, int pool_size) 764{ 765 return 0; 766} 767 768static inline void bioset_integrity_free (struct bio_set *bs) 769{ 770 return; 771} 772 773static inline bool bio_integrity_prep(struct bio *bio) 774{ 775 return true; 776} 777 778static inline int bio_integrity_clone(struct bio *bio, struct bio *bio_src, 779 gfp_t gfp_mask) 780{ 781 return 0; 782} 783 784static inline void bio_integrity_advance(struct bio *bio, 785 unsigned int bytes_done) 786{ 787 return; 788} 789 790static inline void bio_integrity_trim(struct bio *bio) 791{ 792 return; 793} 794 795static inline void bio_integrity_init(void) 796{ 797 return; 798} 799 800static inline bool bio_integrity_flagged(struct bio *bio, enum bip_flags flag) 801{ 802 return false; 803} 804 805static inline void *bio_integrity_alloc(struct bio * bio, gfp_t gfp, 806 unsigned int nr) 807{ 808 return ERR_PTR(-EINVAL); 809} 810 811static inline int bio_integrity_add_page(struct bio *bio, struct page *page, 812 unsigned int len, unsigned int offset) 813{ 814 return 0; 815} 816 817#endif /* CONFIG_BLK_DEV_INTEGRITY */ 818 819/* 820 * Mark a bio as polled. Note that for async polled IO, the caller must 821 * expect -EWOULDBLOCK if we cannot allocate a request (or other resources). 822 * We cannot block waiting for requests on polled IO, as those completions 823 * must be found by the caller. This is different than IRQ driven IO, where 824 * it's safe to wait for IO to complete. 825 */ 826static inline void bio_set_polled(struct bio *bio, struct kiocb *kiocb) 827{ 828 bio->bi_opf |= REQ_HIPRI; 829 if (!is_sync_kiocb(kiocb)) 830 bio->bi_opf |= REQ_NOWAIT; 831} 832 833#endif /* CONFIG_BLOCK */ 834#endif /* __LINUX_BIO_H */