1 /* 2 * Copyright (C) 2001 Jens Axboe <axboe@suse.de> 3 * 4 * This program is free software; you can redistribute it and/or modify 5 * it under the terms of the GNU General Public License version 2 as 6 * published by the Free Software Foundation. 7 * 8 * This program is distributed in the hope that it will be useful, 9 * but WITHOUT ANY WARRANTY; without even the implied warranty of 10 * 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 12 * GNU General Public License for more details. 13 * 14 * You should have received a copy of the GNU General Public Licens 15 * along with this program; if not, write to the Free Software 16 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111- 17 */ 18 #ifndef __LINUX_BIO_H 19 #define __LINUX_BIO_H 20 21 #include <linux/highmem.h> 22 #include <linux/mempool.h> 23 #include <linux/ioprio.h> 24 #include <linux/bug.h> 25 26 #ifdef CONFIG_BLOCK 27 28 #include <asm/io.h> 29 30 /* struct bio, bio_vec and BIO_* flags are defined in blk_types.h */ 31 #include <linux/blk_types.h> 32 33 #define BIO_DEBUG 34 35 #ifdef BIO_DEBUG 36 #define BIO_BUG_ON BUG_ON 37 #else 38 #define BIO_BUG_ON 39 #endif 40 41 #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_ZEROES: 201 return 0; 202 case REQ_OP_WRITE_SAME: 203 return 1; 204 default: 205 break; 206 } 207 208 bio_for_each_segment(bv, bio, iter) 209 segs++; 210 211 return segs; 212 } 213 214 /* 215 * get a reference to a bio, so it won't disappear. the intended use is 216 * something like: 217 * 218 * bio_get(bio); 219 * submit_bio(rw, bio); 220 * if (bio->bi_flags ...) 221 * do_something 222 * bio_put(bio); 223 * 224 * without the bio_get(), it could potentially complete I/O before submit_bio 225 * returns. and then bio would be freed memory when if (bio->bi_flags ...) 226 * runs 227 */ 228 static inline void bio_get(struct bio *bio) 229 { 230 bio->bi_flags |= (1 << BIO_REFFED); 231 smp_mb__before_atomic(); 232 atomic_inc(&bio->__bi_cnt); 233 } 234 235 static inline void bio_cnt_set(struct bio *bio, unsigned int count) 236 { 237 if (count != 1) { 238 bio->bi_flags |= (1 << BIO_REFFED); 239 smp_mb__before_atomic(); 240 } 241 atomic_set(&bio->__bi_cnt, count); 242 } 243 244 static inline bool bio_flagged(struct bio *bio, unsigned int bit) 245 { 246 return (bio->bi_flags & (1U << bit)) != 0; 247 } 248 249 static inline void bio_set_flag(struct bio *bio, unsigned int bit) 250 { 251 bio->bi_flags |= (1U << bit); 252 } 253 254 static inline void bio_clear_flag(struct bio *bio, unsigned int bit) 255 { 256 bio->bi_flags &= ~(1U << bit); 257 } 258 259 static inline void bio_get_first_bvec(struct bio *bio, struct bio_vec *bv) 260 { 261 *bv = bio_iovec(bio); 262 } 263 264 static inline void bio_get_last_bvec(struct bio *bio, struct bio_vec *bv) 265 { 266 struct bvec_iter iter = bio->bi_iter; 267 int idx; 268 269 if (unlikely(!bio_multiple_segments(bio))) { 270 *bv = bio_iovec(bio); 271 return; 272 } 273 274 bio_advance_iter(bio, &iter, iter.bi_size); 275 276 if (!iter.bi_bvec_done) 277 idx = iter.bi_idx - 1; 278 else /* in the middle of bvec */ 279 idx = iter.bi_idx; 280 281 *bv = bio->bi_io_vec[idx]; 282 283 /* 284 * iter.bi_bvec_done records actual length of the last bvec 285 * if this bio ends in the middle of one io vector 286 */ 287 if (iter.bi_bvec_done) 288 bv->bv_len = iter.bi_bvec_done; 289 } 290 291 enum bip_flags { 292 BIP_BLOCK_INTEGRITY = 1 << 0, /* block layer owns integrity data */ 293 BIP_MAPPED_INTEGRITY = 1 << 1, /* ref tag has been remapped */ 294 BIP_CTRL_NOCHECK = 1 << 2, /* disable HBA integrity checking */ 295 BIP_DISK_NOCHECK = 1 << 3, /* disable disk integrity checking */ 296 BIP_IP_CHECKSUM = 1 << 4, /* IP checksum */ 297 }; 298 299 /* 300 * bio integrity payload 301 */ 302 struct bio_integrity_payload { 303 struct bio *bip_bio; /* parent bio */ 304 305 struct bvec_iter bip_iter; 306 307 bio_end_io_t *bip_end_io; /* saved I/O completion fn */ 308 309 unsigned short bip_slab; /* slab the bip came from */ 310 unsigned short bip_vcnt; /* # of integrity bio_vecs */ 311 unsigned short bip_max_vcnt; /* integrity bio_vec slots */ 312 unsigned short bip_flags; /* control flags */ 313 314 struct work_struct bip_work; /* I/O completion */ 315 316 struct bio_vec *bip_vec; 317 struct bio_vec bip_inline_vecs[0];/* embedded bvec array */ 318 }; 319 320 #if defined(CONFIG_BLK_DEV_INTEGRITY) 321 322 static inline struct bio_integrity_payload *bio_integrity(struct bio *bio) 323 { 324 if (bio->bi_opf & REQ_INTEGRITY) 325 return bio->bi_integrity; 326 327 return NULL; 328 } 329 330 static inline bool bio_integrity_flagged(struct bio *bio, enum bip_flags flag) 331 { 332 struct bio_integrity_payload *bip = bio_integrity(bio); 333 334 if (bip) 335 return bip->bip_flags & flag; 336 337 return false; 338 } 339 340 static inline sector_t bip_get_seed(struct bio_integrity_payload *bip) 341 { 342 return bip->bip_iter.bi_sector; 343 } 344 345 static inline void bip_set_seed(struct bio_integrity_payload *bip, 346 sector_t seed) 347 { 348 bip->bip_iter.bi_sector = seed; 349 } 350 351 #endif /* CONFIG_BLK_DEV_INTEGRITY */ 352 353 extern void bio_trim(struct bio *bio, int offset, int size); 354 extern struct bio *bio_split(struct bio *bio, int sectors, 355 gfp_t gfp, struct bio_set *bs); 356 357 /** 358 * bio_next_split - get next @sectors from a bio, splitting if necessary 359 * @bio: bio to split 360 * @sectors: number of sectors to split from the front of @bio 361 * @gfp: gfp mask 362 * @bs: bio set to allocate from 363 * 364 * Returns a bio representing the next @sectors of @bio - if the bio is smaller 365 * than @sectors, returns the original bio unchanged. 366 */ 367 static inline struct bio *bio_next_split(struct bio *bio, int sectors, 368 gfp_t gfp, struct bio_set *bs) 369 { 370 if (sectors >= bio_sectors(bio)) 371 return bio; 372 373 return bio_split(bio, sectors, gfp, bs); 374 } 375 376 extern struct bio_set *bioset_create(unsigned int, unsigned int); 377 extern struct bio_set *bioset_create_nobvec(unsigned int, unsigned int); 378 extern void bioset_free(struct bio_set *); 379 extern mempool_t *biovec_create_pool(int pool_entries); 380 381 extern struct bio *bio_alloc_bioset(gfp_t, int, struct bio_set *); 382 extern void bio_put(struct bio *); 383 384 extern void __bio_clone_fast(struct bio *, struct bio *); 385 extern struct bio *bio_clone_fast(struct bio *, gfp_t, struct bio_set *); 386 extern struct bio *bio_clone_bioset(struct bio *, gfp_t, struct bio_set *bs); 387 388 extern struct bio_set *fs_bio_set; 389 390 static inline struct bio *bio_alloc(gfp_t gfp_mask, unsigned int nr_iovecs) 391 { 392 return bio_alloc_bioset(gfp_mask, nr_iovecs, fs_bio_set); 393 } 394 395 static inline struct bio *bio_clone(struct bio *bio, gfp_t gfp_mask) 396 { 397 return bio_clone_bioset(bio, gfp_mask, fs_bio_set); 398 } 399 400 static inline struct bio *bio_kmalloc(gfp_t gfp_mask, unsigned int nr_iovecs) 401 { 402 return bio_alloc_bioset(gfp_mask, nr_iovecs, NULL); 403 } 404 405 static inline struct bio *bio_clone_kmalloc(struct bio *bio, gfp_t gfp_mask) 406 { 407 return bio_clone_bioset(bio, gfp_mask, NULL); 408 409 } 410 411 extern blk_qc_t submit_bio(struct bio *); 412 413 extern void bio_endio(struct bio *); 414 415 static inline void bio_io_error(struct bio *bio) 416 { 417 bio->bi_error = -EIO; 418 bio_endio(bio); 419 } 420 421 struct request_queue; 422 extern int bio_phys_segments(struct request_queue *, struct bio *); 423 424 extern int submit_bio_wait(struct bio *bio); 425 extern void bio_advance(struct bio *, unsigned); 426 427 extern void bio_init(struct bio *bio, struct bio_vec *table, 428 unsigned short max_vecs); 429 extern void bio_reset(struct bio *); 430 void bio_chain(struct bio *, struct bio *); 431 432 extern int bio_add_page(struct bio *, struct page *, unsigned int,unsigned int); 433 extern int bio_add_pc_page(struct request_queue *, struct bio *, struct page *, 434 unsigned int, unsigned int); 435 int bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter); 436 struct rq_map_data; 437 extern struct bio *bio_map_user_iov(struct request_queue *, 438 const struct iov_iter *, gfp_t); 439 extern void bio_unmap_user(struct bio *); 440 extern struct bio *bio_map_kern(struct request_queue *, void *, unsigned int, 441 gfp_t); 442 extern struct bio *bio_copy_kern(struct request_queue *, void *, unsigned int, 443 gfp_t, int); 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(int rw, unsigned long sectors, 448 struct hd_struct *part); 449 void generic_end_io_acct(int rw, struct hd_struct *part, 450 unsigned long start_time); 451 452 #ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 453 # error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform" 454 #endif 455 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 456 extern void bio_flush_dcache_pages(struct bio *bi); 457 #else 458 static inline void bio_flush_dcache_pages(struct bio *bi) 459 { 460 } 461 #endif 462 463 extern void bio_copy_data(struct bio *dst, struct bio *src); 464 extern int bio_alloc_pages(struct bio *bio, gfp_t gfp); 465 extern void bio_free_pages(struct bio *bio); 466 467 extern struct bio *bio_copy_user_iov(struct request_queue *, 468 struct rq_map_data *, 469 const struct iov_iter *, 470 gfp_t); 471 extern int bio_uncopy_user(struct bio *); 472 void zero_fill_bio(struct bio *bio); 473 extern struct bio_vec *bvec_alloc(gfp_t, int, unsigned long *, mempool_t *); 474 extern void bvec_free(mempool_t *, struct bio_vec *, unsigned int); 475 extern unsigned int bvec_nr_vecs(unsigned short idx); 476 477 #ifdef CONFIG_BLK_CGROUP 478 int bio_associate_blkcg(struct bio *bio, struct cgroup_subsys_state *blkcg_css); 479 int bio_associate_current(struct bio *bio); 480 void bio_disassociate_task(struct bio *bio); 481 void bio_clone_blkcg_association(struct bio *dst, struct bio *src); 482 #else /* CONFIG_BLK_CGROUP */ 483 static inline int bio_associate_blkcg(struct bio *bio, 484 struct cgroup_subsys_state *blkcg_css) { return 0; } 485 static inline int bio_associate_current(struct bio *bio) { return -ENOENT; } 486 static inline void bio_disassociate_task(struct bio *bio) { } 487 static inline void bio_clone_blkcg_association(struct bio *dst, 488 struct bio *src) { } 489 #endif /* CONFIG_BLK_CGROUP */ 490 491 #ifdef CONFIG_HIGHMEM 492 /* 493 * remember never ever reenable interrupts between a bvec_kmap_irq and 494 * bvec_kunmap_irq! 495 */ 496 static inline char *bvec_kmap_irq(struct bio_vec *bvec, unsigned long *flags) 497 { 498 unsigned long addr; 499 500 /* 501 * might not be a highmem page, but the preempt/irq count 502 * balancing is a lot nicer this way 503 */ 504 local_irq_save(*flags); 505 addr = (unsigned long) kmap_atomic(bvec->bv_page); 506 507 BUG_ON(addr & ~PAGE_MASK); 508 509 return (char *) addr + bvec->bv_offset; 510 } 511 512 static inline void bvec_kunmap_irq(char *buffer, unsigned long *flags) 513 { 514 unsigned long ptr = (unsigned long) buffer & PAGE_MASK; 515 516 kunmap_atomic((void *) ptr); 517 local_irq_restore(*flags); 518 } 519 520 #else 521 static inline char *bvec_kmap_irq(struct bio_vec *bvec, unsigned long *flags) 522 { 523 return page_address(bvec->bv_page) + bvec->bv_offset; 524 } 525 526 static inline void bvec_kunmap_irq(char *buffer, unsigned long *flags) 527 { 528 *flags = 0; 529 } 530 #endif 531 532 static inline char *__bio_kmap_irq(struct bio *bio, struct bvec_iter iter, 533 unsigned long *flags) 534 { 535 return bvec_kmap_irq(&bio_iter_iovec(bio, iter), flags); 536 } 537 #define __bio_kunmap_irq(buf, flags) bvec_kunmap_irq(buf, flags) 538 539 #define bio_kmap_irq(bio, flags) \ 540 __bio_kmap_irq((bio), (bio)->bi_iter, (flags)) 541 #define bio_kunmap_irq(buf,flags) __bio_kunmap_irq(buf, flags) 542 543 /* 544 * BIO list management for use by remapping drivers (e.g. DM or MD) and loop. 545 * 546 * A bio_list anchors a singly-linked list of bios chained through the bi_next 547 * member of the bio. The bio_list also caches the last list member to allow 548 * fast access to the tail. 549 */ 550 struct bio_list { 551 struct bio *head; 552 struct bio *tail; 553 }; 554 555 static inline int bio_list_empty(const struct bio_list *bl) 556 { 557 return bl->head == NULL; 558 } 559 560 static inline void bio_list_init(struct bio_list *bl) 561 { 562 bl->head = bl->tail = NULL; 563 } 564 565 #define BIO_EMPTY_LIST { NULL, NULL } 566 567 #define bio_list_for_each(bio, bl) \ 568 for (bio = (bl)->head; bio; bio = bio->bi_next) 569 570 static inline unsigned bio_list_size(const struct bio_list *bl) 571 { 572 unsigned sz = 0; 573 struct bio *bio; 574 575 bio_list_for_each(bio, bl) 576 sz++; 577 578 return sz; 579 } 580 581 static inline void bio_list_add(struct bio_list *bl, struct bio *bio) 582 { 583 bio->bi_next = NULL; 584 585 if (bl->tail) 586 bl->tail->bi_next = bio; 587 else 588 bl->head = bio; 589 590 bl->tail = bio; 591 } 592 593 static inline void bio_list_add_head(struct bio_list *bl, struct bio *bio) 594 { 595 bio->bi_next = bl->head; 596 597 bl->head = bio; 598 599 if (!bl->tail) 600 bl->tail = bio; 601 } 602 603 static inline void bio_list_merge(struct bio_list *bl, struct bio_list *bl2) 604 { 605 if (!bl2->head) 606 return; 607 608 if (bl->tail) 609 bl->tail->bi_next = bl2->head; 610 else 611 bl->head = bl2->head; 612 613 bl->tail = bl2->tail; 614 } 615 616 static inline void bio_list_merge_head(struct bio_list *bl, 617 struct bio_list *bl2) 618 { 619 if (!bl2->head) 620 return; 621 622 if (bl->head) 623 bl2->tail->bi_next = bl->head; 624 else 625 bl->tail = bl2->tail; 626 627 bl->head = bl2->head; 628 } 629 630 static inline struct bio *bio_list_peek(struct bio_list *bl) 631 { 632 return bl->head; 633 } 634 635 static inline struct bio *bio_list_pop(struct bio_list *bl) 636 { 637 struct bio *bio = bl->head; 638 639 if (bio) { 640 bl->head = bl->head->bi_next; 641 if (!bl->head) 642 bl->tail = NULL; 643 644 bio->bi_next = NULL; 645 } 646 647 return bio; 648 } 649 650 static inline struct bio *bio_list_get(struct bio_list *bl) 651 { 652 struct bio *bio = bl->head; 653 654 bl->head = bl->tail = NULL; 655 656 return bio; 657 } 658 659 /* 660 * Increment chain count for the bio. Make sure the CHAIN flag update 661 * is visible before the raised count. 662 */ 663 static inline void bio_inc_remaining(struct bio *bio) 664 { 665 bio_set_flag(bio, BIO_CHAIN); 666 smp_mb__before_atomic(); 667 atomic_inc(&bio->__bi_remaining); 668 } 669 670 /* 671 * bio_set is used to allow other portions of the IO system to 672 * allocate their own private memory pools for bio and iovec structures. 673 * These memory pools in turn all allocate from the bio_slab 674 * and the bvec_slabs[]. 675 */ 676 #define BIO_POOL_SIZE 2 677 678 struct bio_set { 679 struct kmem_cache *bio_slab; 680 unsigned int front_pad; 681 682 mempool_t *bio_pool; 683 mempool_t *bvec_pool; 684 #if defined(CONFIG_BLK_DEV_INTEGRITY) 685 mempool_t *bio_integrity_pool; 686 mempool_t *bvec_integrity_pool; 687 #endif 688 689 /* 690 * Deadlock avoidance for stacking block drivers: see comments in 691 * bio_alloc_bioset() for details 692 */ 693 spinlock_t rescue_lock; 694 struct bio_list rescue_list; 695 struct work_struct rescue_work; 696 struct workqueue_struct *rescue_workqueue; 697 }; 698 699 struct biovec_slab { 700 int nr_vecs; 701 char *name; 702 struct kmem_cache *slab; 703 }; 704 705 /* 706 * a small number of entries is fine, not going to be performance critical. 707 * basically we just need to survive 708 */ 709 #define BIO_SPLIT_ENTRIES 2 710 711 #if defined(CONFIG_BLK_DEV_INTEGRITY) 712 713 #define bip_for_each_vec(bvl, bip, iter) \ 714 for_each_bvec(bvl, (bip)->bip_vec, iter, (bip)->bip_iter) 715 716 #define bio_for_each_integrity_vec(_bvl, _bio, _iter) \ 717 for_each_bio(_bio) \ 718 bip_for_each_vec(_bvl, _bio->bi_integrity, _iter) 719 720 extern struct bio_integrity_payload *bio_integrity_alloc(struct bio *, gfp_t, unsigned int); 721 extern void bio_integrity_free(struct bio *); 722 extern int bio_integrity_add_page(struct bio *, struct page *, unsigned int, unsigned int); 723 extern bool bio_integrity_enabled(struct bio *bio); 724 extern int bio_integrity_prep(struct bio *); 725 extern void bio_integrity_endio(struct bio *); 726 extern void bio_integrity_advance(struct bio *, unsigned int); 727 extern void bio_integrity_trim(struct bio *, unsigned int, unsigned int); 728 extern int bio_integrity_clone(struct bio *, struct bio *, gfp_t); 729 extern int bioset_integrity_create(struct bio_set *, int); 730 extern void bioset_integrity_free(struct bio_set *); 731 extern void bio_integrity_init(void); 732 733 #else /* CONFIG_BLK_DEV_INTEGRITY */ 734 735 static inline void *bio_integrity(struct bio *bio) 736 { 737 return NULL; 738 } 739 740 static inline bool bio_integrity_enabled(struct bio *bio) 741 { 742 return false; 743 } 744 745 static inline int bioset_integrity_create(struct bio_set *bs, int pool_size) 746 { 747 return 0; 748 } 749 750 static inline void bioset_integrity_free (struct bio_set *bs) 751 { 752 return; 753 } 754 755 static inline int bio_integrity_prep(struct bio *bio) 756 { 757 return 0; 758 } 759 760 static inline void bio_integrity_free(struct bio *bio) 761 { 762 return; 763 } 764 765 static inline int bio_integrity_clone(struct bio *bio, struct bio *bio_src, 766 gfp_t gfp_mask) 767 { 768 return 0; 769 } 770 771 static inline void bio_integrity_advance(struct bio *bio, 772 unsigned int bytes_done) 773 { 774 return; 775 } 776 777 static inline void bio_integrity_trim(struct bio *bio, unsigned int offset, 778 unsigned int sectors) 779 { 780 return; 781 } 782 783 static inline void bio_integrity_init(void) 784 { 785 return; 786 } 787 788 static inline bool bio_integrity_flagged(struct bio *bio, enum bip_flags flag) 789 { 790 return false; 791 } 792 793 static inline void *bio_integrity_alloc(struct bio * bio, gfp_t gfp, 794 unsigned int nr) 795 { 796 return ERR_PTR(-EINVAL); 797 } 798 799 static inline int bio_integrity_add_page(struct bio *bio, struct page *page, 800 unsigned int len, unsigned int offset) 801 { 802 return 0; 803 } 804 805 #endif /* CONFIG_BLK_DEV_INTEGRITY */ 806 807 #endif /* CONFIG_BLOCK */ 808 #endif /* __LINUX_BIO_H */ 809