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 bvec_to_phys(bv) (page_to_phys((bv)->bv_page) + (unsigned long) (bv)->bv_offset) 122 123 /* 124 * queues that have highmem support enabled may still need to revert to 125 * PIO transfers occasionally and thus map high pages temporarily. For 126 * permanent PIO fall back, user is probably better off disabling highmem 127 * I/O completely on that queue (see ide-dma for example) 128 */ 129 #define __bio_kmap_atomic(bio, iter) \ 130 (kmap_atomic(bio_iter_iovec((bio), (iter)).bv_page) + \ 131 bio_iter_iovec((bio), (iter)).bv_offset) 132 133 #define __bio_kunmap_atomic(addr) kunmap_atomic(addr) 134 135 /* 136 * merge helpers etc 137 */ 138 139 /* Default implementation of BIOVEC_PHYS_MERGEABLE */ 140 #define __BIOVEC_PHYS_MERGEABLE(vec1, vec2) \ 141 ((bvec_to_phys((vec1)) + (vec1)->bv_len) == bvec_to_phys((vec2))) 142 143 /* 144 * allow arch override, for eg virtualized architectures (put in asm/io.h) 145 */ 146 #ifndef BIOVEC_PHYS_MERGEABLE 147 #define BIOVEC_PHYS_MERGEABLE(vec1, vec2) \ 148 __BIOVEC_PHYS_MERGEABLE(vec1, vec2) 149 #endif 150 151 #define __BIO_SEG_BOUNDARY(addr1, addr2, mask) \ 152 (((addr1) | (mask)) == (((addr2) - 1) | (mask))) 153 #define BIOVEC_SEG_BOUNDARY(q, b1, b2) \ 154 __BIO_SEG_BOUNDARY(bvec_to_phys((b1)), bvec_to_phys((b2)) + (b2)->bv_len, queue_segment_boundary((q))) 155 156 /* 157 * drivers should _never_ use the all version - the bio may have been split 158 * before it got to the driver and the driver won't own all of it 159 */ 160 #define bio_for_each_segment_all(bvl, bio, i) \ 161 for (i = 0, bvl = (bio)->bi_io_vec; i < (bio)->bi_vcnt; i++, bvl++) 162 163 static inline void bio_advance_iter(struct bio *bio, struct bvec_iter *iter, 164 unsigned bytes) 165 { 166 iter->bi_sector += bytes >> 9; 167 168 if (bio_no_advance_iter(bio)) 169 iter->bi_size -= bytes; 170 else 171 bvec_iter_advance(bio->bi_io_vec, iter, bytes); 172 } 173 174 #define __bio_for_each_segment(bvl, bio, iter, start) \ 175 for (iter = (start); \ 176 (iter).bi_size && \ 177 ((bvl = bio_iter_iovec((bio), (iter))), 1); \ 178 bio_advance_iter((bio), &(iter), (bvl).bv_len)) 179 180 #define bio_for_each_segment(bvl, bio, iter) \ 181 __bio_for_each_segment(bvl, bio, iter, (bio)->bi_iter) 182 183 #define bio_iter_last(bvec, iter) ((iter).bi_size == (bvec).bv_len) 184 185 static inline unsigned bio_segments(struct bio *bio) 186 { 187 unsigned segs = 0; 188 struct bio_vec bv; 189 struct bvec_iter iter; 190 191 /* 192 * We special case discard/write same/write zeroes, because they 193 * interpret bi_size differently: 194 */ 195 196 switch (bio_op(bio)) { 197 case REQ_OP_DISCARD: 198 case REQ_OP_SECURE_ERASE: 199 case REQ_OP_WRITE_ZEROES: 200 return 0; 201 case REQ_OP_WRITE_SAME: 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, int flags); 376 enum { 377 BIOSET_NEED_BVECS = BIT(0), 378 BIOSET_NEED_RESCUER = BIT(1), 379 }; 380 extern void bioset_free(struct bio_set *); 381 extern mempool_t *biovec_create_pool(int pool_entries); 382 383 extern struct bio *bio_alloc_bioset(gfp_t, unsigned int, struct bio_set *); 384 extern void bio_put(struct bio *); 385 386 extern void __bio_clone_fast(struct bio *, struct bio *); 387 extern struct bio *bio_clone_fast(struct bio *, gfp_t, struct bio_set *); 388 extern struct bio *bio_clone_bioset(struct bio *, gfp_t, struct bio_set *bs); 389 390 extern struct bio_set *fs_bio_set; 391 392 static inline struct bio *bio_alloc(gfp_t gfp_mask, unsigned int nr_iovecs) 393 { 394 return bio_alloc_bioset(gfp_mask, nr_iovecs, fs_bio_set); 395 } 396 397 static inline struct bio *bio_kmalloc(gfp_t gfp_mask, unsigned int nr_iovecs) 398 { 399 return bio_alloc_bioset(gfp_mask, nr_iovecs, NULL); 400 } 401 402 static inline struct bio *bio_clone_kmalloc(struct bio *bio, gfp_t gfp_mask) 403 { 404 return bio_clone_bioset(bio, gfp_mask, NULL); 405 406 } 407 408 extern blk_qc_t submit_bio(struct bio *); 409 410 extern void bio_endio(struct bio *); 411 412 static inline void bio_io_error(struct bio *bio) 413 { 414 bio->bi_status = BLK_STS_IOERR; 415 bio_endio(bio); 416 } 417 418 static inline void bio_wouldblock_error(struct bio *bio) 419 { 420 bio->bi_status = BLK_STS_AGAIN; 421 bio_endio(bio); 422 } 423 424 struct request_queue; 425 extern int bio_phys_segments(struct request_queue *, struct bio *); 426 427 extern int submit_bio_wait(struct bio *bio); 428 extern void bio_advance(struct bio *, unsigned); 429 430 extern void bio_init(struct bio *bio, struct bio_vec *table, 431 unsigned short max_vecs); 432 extern void bio_uninit(struct bio *); 433 extern void bio_reset(struct bio *); 434 void bio_chain(struct bio *, struct bio *); 435 436 extern int bio_add_page(struct bio *, struct page *, unsigned int,unsigned int); 437 extern int bio_add_pc_page(struct request_queue *, struct bio *, struct page *, 438 unsigned int, unsigned int); 439 int bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter); 440 struct rq_map_data; 441 extern struct bio *bio_map_user_iov(struct request_queue *, 442 const struct iov_iter *, gfp_t); 443 extern void bio_unmap_user(struct bio *); 444 extern struct bio *bio_map_kern(struct request_queue *, void *, unsigned int, 445 gfp_t); 446 extern struct bio *bio_copy_kern(struct request_queue *, void *, unsigned int, 447 gfp_t, int); 448 extern void bio_set_pages_dirty(struct bio *bio); 449 extern void bio_check_pages_dirty(struct bio *bio); 450 451 void generic_start_io_acct(int rw, unsigned long sectors, 452 struct hd_struct *part); 453 void generic_end_io_acct(int rw, struct hd_struct *part, 454 unsigned long start_time); 455 456 #ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 457 # error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform" 458 #endif 459 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 460 extern void bio_flush_dcache_pages(struct bio *bi); 461 #else 462 static inline void bio_flush_dcache_pages(struct bio *bi) 463 { 464 } 465 #endif 466 467 extern void bio_copy_data(struct bio *dst, struct bio *src); 468 extern int bio_alloc_pages(struct bio *bio, gfp_t gfp); 469 extern void bio_free_pages(struct bio *bio); 470 471 extern struct bio *bio_copy_user_iov(struct request_queue *, 472 struct rq_map_data *, 473 const struct iov_iter *, 474 gfp_t); 475 extern int bio_uncopy_user(struct bio *); 476 void zero_fill_bio(struct bio *bio); 477 extern struct bio_vec *bvec_alloc(gfp_t, int, unsigned long *, mempool_t *); 478 extern void bvec_free(mempool_t *, struct bio_vec *, unsigned int); 479 extern unsigned int bvec_nr_vecs(unsigned short idx); 480 481 #ifdef CONFIG_BLK_CGROUP 482 int bio_associate_blkcg(struct bio *bio, struct cgroup_subsys_state *blkcg_css); 483 int bio_associate_current(struct bio *bio); 484 void bio_disassociate_task(struct bio *bio); 485 void bio_clone_blkcg_association(struct bio *dst, struct bio *src); 486 #else /* CONFIG_BLK_CGROUP */ 487 static inline int bio_associate_blkcg(struct bio *bio, 488 struct cgroup_subsys_state *blkcg_css) { return 0; } 489 static inline int bio_associate_current(struct bio *bio) { return -ENOENT; } 490 static inline void bio_disassociate_task(struct bio *bio) { } 491 static inline void bio_clone_blkcg_association(struct bio *dst, 492 struct bio *src) { } 493 #endif /* CONFIG_BLK_CGROUP */ 494 495 #ifdef CONFIG_HIGHMEM 496 /* 497 * remember never ever reenable interrupts between a bvec_kmap_irq and 498 * bvec_kunmap_irq! 499 */ 500 static inline char *bvec_kmap_irq(struct bio_vec *bvec, unsigned long *flags) 501 { 502 unsigned long addr; 503 504 /* 505 * might not be a highmem page, but the preempt/irq count 506 * balancing is a lot nicer this way 507 */ 508 local_irq_save(*flags); 509 addr = (unsigned long) kmap_atomic(bvec->bv_page); 510 511 BUG_ON(addr & ~PAGE_MASK); 512 513 return (char *) addr + bvec->bv_offset; 514 } 515 516 static inline void bvec_kunmap_irq(char *buffer, unsigned long *flags) 517 { 518 unsigned long ptr = (unsigned long) buffer & PAGE_MASK; 519 520 kunmap_atomic((void *) ptr); 521 local_irq_restore(*flags); 522 } 523 524 #else 525 static inline char *bvec_kmap_irq(struct bio_vec *bvec, unsigned long *flags) 526 { 527 return page_address(bvec->bv_page) + bvec->bv_offset; 528 } 529 530 static inline void bvec_kunmap_irq(char *buffer, unsigned long *flags) 531 { 532 *flags = 0; 533 } 534 #endif 535 536 static inline char *__bio_kmap_irq(struct bio *bio, struct bvec_iter iter, 537 unsigned long *flags) 538 { 539 return bvec_kmap_irq(&bio_iter_iovec(bio, iter), flags); 540 } 541 #define __bio_kunmap_irq(buf, flags) bvec_kunmap_irq(buf, flags) 542 543 #define bio_kmap_irq(bio, flags) \ 544 __bio_kmap_irq((bio), (bio)->bi_iter, (flags)) 545 #define bio_kunmap_irq(buf,flags) __bio_kunmap_irq(buf, flags) 546 547 /* 548 * BIO list management for use by remapping drivers (e.g. DM or MD) and loop. 549 * 550 * A bio_list anchors a singly-linked list of bios chained through the bi_next 551 * member of the bio. The bio_list also caches the last list member to allow 552 * fast access to the tail. 553 */ 554 struct bio_list { 555 struct bio *head; 556 struct bio *tail; 557 }; 558 559 static inline int bio_list_empty(const struct bio_list *bl) 560 { 561 return bl->head == NULL; 562 } 563 564 static inline void bio_list_init(struct bio_list *bl) 565 { 566 bl->head = bl->tail = NULL; 567 } 568 569 #define BIO_EMPTY_LIST { NULL, NULL } 570 571 #define bio_list_for_each(bio, bl) \ 572 for (bio = (bl)->head; bio; bio = bio->bi_next) 573 574 static inline unsigned bio_list_size(const struct bio_list *bl) 575 { 576 unsigned sz = 0; 577 struct bio *bio; 578 579 bio_list_for_each(bio, bl) 580 sz++; 581 582 return sz; 583 } 584 585 static inline void bio_list_add(struct bio_list *bl, struct bio *bio) 586 { 587 bio->bi_next = NULL; 588 589 if (bl->tail) 590 bl->tail->bi_next = bio; 591 else 592 bl->head = bio; 593 594 bl->tail = bio; 595 } 596 597 static inline void bio_list_add_head(struct bio_list *bl, struct bio *bio) 598 { 599 bio->bi_next = bl->head; 600 601 bl->head = bio; 602 603 if (!bl->tail) 604 bl->tail = bio; 605 } 606 607 static inline void bio_list_merge(struct bio_list *bl, struct bio_list *bl2) 608 { 609 if (!bl2->head) 610 return; 611 612 if (bl->tail) 613 bl->tail->bi_next = bl2->head; 614 else 615 bl->head = bl2->head; 616 617 bl->tail = bl2->tail; 618 } 619 620 static inline void bio_list_merge_head(struct bio_list *bl, 621 struct bio_list *bl2) 622 { 623 if (!bl2->head) 624 return; 625 626 if (bl->head) 627 bl2->tail->bi_next = bl->head; 628 else 629 bl->tail = bl2->tail; 630 631 bl->head = bl2->head; 632 } 633 634 static inline struct bio *bio_list_peek(struct bio_list *bl) 635 { 636 return bl->head; 637 } 638 639 static inline struct bio *bio_list_pop(struct bio_list *bl) 640 { 641 struct bio *bio = bl->head; 642 643 if (bio) { 644 bl->head = bl->head->bi_next; 645 if (!bl->head) 646 bl->tail = NULL; 647 648 bio->bi_next = NULL; 649 } 650 651 return bio; 652 } 653 654 static inline struct bio *bio_list_get(struct bio_list *bl) 655 { 656 struct bio *bio = bl->head; 657 658 bl->head = bl->tail = NULL; 659 660 return bio; 661 } 662 663 /* 664 * Increment chain count for the bio. Make sure the CHAIN flag update 665 * is visible before the raised count. 666 */ 667 static inline void bio_inc_remaining(struct bio *bio) 668 { 669 bio_set_flag(bio, BIO_CHAIN); 670 smp_mb__before_atomic(); 671 atomic_inc(&bio->__bi_remaining); 672 } 673 674 /* 675 * bio_set is used to allow other portions of the IO system to 676 * allocate their own private memory pools for bio and iovec structures. 677 * These memory pools in turn all allocate from the bio_slab 678 * and the bvec_slabs[]. 679 */ 680 #define BIO_POOL_SIZE 2 681 682 struct bio_set { 683 struct kmem_cache *bio_slab; 684 unsigned int front_pad; 685 686 mempool_t *bio_pool; 687 mempool_t *bvec_pool; 688 #if defined(CONFIG_BLK_DEV_INTEGRITY) 689 mempool_t *bio_integrity_pool; 690 mempool_t *bvec_integrity_pool; 691 #endif 692 693 /* 694 * Deadlock avoidance for stacking block drivers: see comments in 695 * bio_alloc_bioset() for details 696 */ 697 spinlock_t rescue_lock; 698 struct bio_list rescue_list; 699 struct work_struct rescue_work; 700 struct workqueue_struct *rescue_workqueue; 701 }; 702 703 struct biovec_slab { 704 int nr_vecs; 705 char *name; 706 struct kmem_cache *slab; 707 }; 708 709 /* 710 * a small number of entries is fine, not going to be performance critical. 711 * basically we just need to survive 712 */ 713 #define BIO_SPLIT_ENTRIES 2 714 715 #if defined(CONFIG_BLK_DEV_INTEGRITY) 716 717 #define bip_for_each_vec(bvl, bip, iter) \ 718 for_each_bvec(bvl, (bip)->bip_vec, iter, (bip)->bip_iter) 719 720 #define bio_for_each_integrity_vec(_bvl, _bio, _iter) \ 721 for_each_bio(_bio) \ 722 bip_for_each_vec(_bvl, _bio->bi_integrity, _iter) 723 724 extern struct bio_integrity_payload *bio_integrity_alloc(struct bio *, gfp_t, unsigned int); 725 extern void bio_integrity_free(struct bio *); 726 extern int bio_integrity_add_page(struct bio *, struct page *, unsigned int, unsigned int); 727 extern bool bio_integrity_enabled(struct bio *bio); 728 extern int bio_integrity_prep(struct bio *); 729 extern void bio_integrity_endio(struct bio *); 730 extern void bio_integrity_advance(struct bio *, unsigned int); 731 extern void bio_integrity_trim(struct bio *, unsigned int, unsigned int); 732 extern int bio_integrity_clone(struct bio *, struct bio *, gfp_t); 733 extern int bioset_integrity_create(struct bio_set *, int); 734 extern void bioset_integrity_free(struct bio_set *); 735 extern void bio_integrity_init(void); 736 737 #else /* CONFIG_BLK_DEV_INTEGRITY */ 738 739 static inline void *bio_integrity(struct bio *bio) 740 { 741 return NULL; 742 } 743 744 static inline bool bio_integrity_enabled(struct bio *bio) 745 { 746 return false; 747 } 748 749 static inline int bioset_integrity_create(struct bio_set *bs, int pool_size) 750 { 751 return 0; 752 } 753 754 static inline void bioset_integrity_free (struct bio_set *bs) 755 { 756 return; 757 } 758 759 static inline int bio_integrity_prep(struct bio *bio) 760 { 761 return 0; 762 } 763 764 static inline void bio_integrity_free(struct bio *bio) 765 { 766 return; 767 } 768 769 static inline int bio_integrity_clone(struct bio *bio, struct bio *bio_src, 770 gfp_t gfp_mask) 771 { 772 return 0; 773 } 774 775 static inline void bio_integrity_advance(struct bio *bio, 776 unsigned int bytes_done) 777 { 778 return; 779 } 780 781 static inline void bio_integrity_trim(struct bio *bio, unsigned int offset, 782 unsigned int sectors) 783 { 784 return; 785 } 786 787 static inline void bio_integrity_init(void) 788 { 789 return; 790 } 791 792 static inline bool bio_integrity_flagged(struct bio *bio, enum bip_flags flag) 793 { 794 return false; 795 } 796 797 static inline void *bio_integrity_alloc(struct bio * bio, gfp_t gfp, 798 unsigned int nr) 799 { 800 return ERR_PTR(-EINVAL); 801 } 802 803 static inline int bio_integrity_add_page(struct bio *bio, struct page *page, 804 unsigned int len, unsigned int offset) 805 { 806 return 0; 807 } 808 809 #endif /* CONFIG_BLK_DEV_INTEGRITY */ 810 811 #endif /* CONFIG_BLOCK */ 812 #endif /* __LINUX_BIO_H */ 813