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