]> git.proxmox.com Git - mirror_ubuntu-bionic-kernel.git/blob - include/linux/bio.h
block: Add bio_end_sector()
[mirror_ubuntu-bionic-kernel.git] / include / linux / bio.h
1 /*
2 * 2.5 block I/O model
3 *
4 * Copyright (C) 2001 Jens Axboe <axboe@suse.de>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 *
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public Licens
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-
19 */
20 #ifndef __LINUX_BIO_H
21 #define __LINUX_BIO_H
22
23 #include <linux/highmem.h>
24 #include <linux/mempool.h>
25 #include <linux/ioprio.h>
26 #include <linux/bug.h>
27
28 #ifdef CONFIG_BLOCK
29
30 #include <asm/io.h>
31
32 /* struct bio, bio_vec and BIO_* flags are defined in blk_types.h */
33 #include <linux/blk_types.h>
34
35 #define BIO_DEBUG
36
37 #ifdef BIO_DEBUG
38 #define BIO_BUG_ON BUG_ON
39 #else
40 #define BIO_BUG_ON
41 #endif
42
43 #define BIO_MAX_PAGES 256
44 #define BIO_MAX_SIZE (BIO_MAX_PAGES << PAGE_CACHE_SHIFT)
45 #define BIO_MAX_SECTORS (BIO_MAX_SIZE >> 9)
46
47 /*
48 * upper 16 bits of bi_rw define the io priority of this bio
49 */
50 #define BIO_PRIO_SHIFT (8 * sizeof(unsigned long) - IOPRIO_BITS)
51 #define bio_prio(bio) ((bio)->bi_rw >> BIO_PRIO_SHIFT)
52 #define bio_prio_valid(bio) ioprio_valid(bio_prio(bio))
53
54 #define bio_set_prio(bio, prio) do { \
55 WARN_ON(prio >= (1 << IOPRIO_BITS)); \
56 (bio)->bi_rw &= ((1UL << BIO_PRIO_SHIFT) - 1); \
57 (bio)->bi_rw |= ((unsigned long) (prio) << BIO_PRIO_SHIFT); \
58 } while (0)
59
60 /*
61 * various member access, note that bio_data should of course not be used
62 * on highmem page vectors
63 */
64 #define bio_iovec_idx(bio, idx) (&((bio)->bi_io_vec[(idx)]))
65 #define bio_iovec(bio) bio_iovec_idx((bio), (bio)->bi_idx)
66 #define bio_page(bio) bio_iovec((bio))->bv_page
67 #define bio_offset(bio) bio_iovec((bio))->bv_offset
68 #define bio_segments(bio) ((bio)->bi_vcnt - (bio)->bi_idx)
69 #define bio_sectors(bio) ((bio)->bi_size >> 9)
70 #define bio_end_sector(bio) ((bio)->bi_sector + bio_sectors((bio)))
71
72 static inline unsigned int bio_cur_bytes(struct bio *bio)
73 {
74 if (bio->bi_vcnt)
75 return bio_iovec(bio)->bv_len;
76 else /* dataless requests such as discard */
77 return bio->bi_size;
78 }
79
80 static inline void *bio_data(struct bio *bio)
81 {
82 if (bio->bi_vcnt)
83 return page_address(bio_page(bio)) + bio_offset(bio);
84
85 return NULL;
86 }
87
88 static inline int bio_has_allocated_vec(struct bio *bio)
89 {
90 return bio->bi_io_vec && bio->bi_io_vec != bio->bi_inline_vecs;
91 }
92
93 /*
94 * will die
95 */
96 #define bio_to_phys(bio) (page_to_phys(bio_page((bio))) + (unsigned long) bio_offset((bio)))
97 #define bvec_to_phys(bv) (page_to_phys((bv)->bv_page) + (unsigned long) (bv)->bv_offset)
98
99 /*
100 * queues that have highmem support enabled may still need to revert to
101 * PIO transfers occasionally and thus map high pages temporarily. For
102 * permanent PIO fall back, user is probably better off disabling highmem
103 * I/O completely on that queue (see ide-dma for example)
104 */
105 #define __bio_kmap_atomic(bio, idx, kmtype) \
106 (kmap_atomic(bio_iovec_idx((bio), (idx))->bv_page) + \
107 bio_iovec_idx((bio), (idx))->bv_offset)
108
109 #define __bio_kunmap_atomic(addr, kmtype) kunmap_atomic(addr)
110
111 /*
112 * merge helpers etc
113 */
114
115 #define __BVEC_END(bio) bio_iovec_idx((bio), (bio)->bi_vcnt - 1)
116 #define __BVEC_START(bio) bio_iovec_idx((bio), (bio)->bi_idx)
117
118 /* Default implementation of BIOVEC_PHYS_MERGEABLE */
119 #define __BIOVEC_PHYS_MERGEABLE(vec1, vec2) \
120 ((bvec_to_phys((vec1)) + (vec1)->bv_len) == bvec_to_phys((vec2)))
121
122 /*
123 * allow arch override, for eg virtualized architectures (put in asm/io.h)
124 */
125 #ifndef BIOVEC_PHYS_MERGEABLE
126 #define BIOVEC_PHYS_MERGEABLE(vec1, vec2) \
127 __BIOVEC_PHYS_MERGEABLE(vec1, vec2)
128 #endif
129
130 #define __BIO_SEG_BOUNDARY(addr1, addr2, mask) \
131 (((addr1) | (mask)) == (((addr2) - 1) | (mask)))
132 #define BIOVEC_SEG_BOUNDARY(q, b1, b2) \
133 __BIO_SEG_BOUNDARY(bvec_to_phys((b1)), bvec_to_phys((b2)) + (b2)->bv_len, queue_segment_boundary((q)))
134 #define BIO_SEG_BOUNDARY(q, b1, b2) \
135 BIOVEC_SEG_BOUNDARY((q), __BVEC_END((b1)), __BVEC_START((b2)))
136
137 #define bio_io_error(bio) bio_endio((bio), -EIO)
138
139 /*
140 * drivers should not use the __ version unless they _really_ want to
141 * run through the entire bio and not just pending pieces
142 */
143 #define __bio_for_each_segment(bvl, bio, i, start_idx) \
144 for (bvl = bio_iovec_idx((bio), (start_idx)), i = (start_idx); \
145 i < (bio)->bi_vcnt; \
146 bvl++, i++)
147
148 #define bio_for_each_segment(bvl, bio, i) \
149 __bio_for_each_segment(bvl, bio, i, (bio)->bi_idx)
150
151 /*
152 * get a reference to a bio, so it won't disappear. the intended use is
153 * something like:
154 *
155 * bio_get(bio);
156 * submit_bio(rw, bio);
157 * if (bio->bi_flags ...)
158 * do_something
159 * bio_put(bio);
160 *
161 * without the bio_get(), it could potentially complete I/O before submit_bio
162 * returns. and then bio would be freed memory when if (bio->bi_flags ...)
163 * runs
164 */
165 #define bio_get(bio) atomic_inc(&(bio)->bi_cnt)
166
167 #if defined(CONFIG_BLK_DEV_INTEGRITY)
168 /*
169 * bio integrity payload
170 */
171 struct bio_integrity_payload {
172 struct bio *bip_bio; /* parent bio */
173
174 sector_t bip_sector; /* virtual start sector */
175
176 void *bip_buf; /* generated integrity data */
177 bio_end_io_t *bip_end_io; /* saved I/O completion fn */
178
179 unsigned int bip_size;
180
181 unsigned short bip_slab; /* slab the bip came from */
182 unsigned short bip_vcnt; /* # of integrity bio_vecs */
183 unsigned short bip_idx; /* current bip_vec index */
184
185 struct work_struct bip_work; /* I/O completion */
186
187 struct bio_vec *bip_vec;
188 struct bio_vec bip_inline_vecs[0];/* embedded bvec array */
189 };
190 #endif /* CONFIG_BLK_DEV_INTEGRITY */
191
192 /*
193 * A bio_pair is used when we need to split a bio.
194 * This can only happen for a bio that refers to just one
195 * page of data, and in the unusual situation when the
196 * page crosses a chunk/device boundary
197 *
198 * The address of the master bio is stored in bio1.bi_private
199 * The address of the pool the pair was allocated from is stored
200 * in bio2.bi_private
201 */
202 struct bio_pair {
203 struct bio bio1, bio2;
204 struct bio_vec bv1, bv2;
205 #if defined(CONFIG_BLK_DEV_INTEGRITY)
206 struct bio_integrity_payload bip1, bip2;
207 struct bio_vec iv1, iv2;
208 #endif
209 atomic_t cnt;
210 int error;
211 };
212 extern struct bio_pair *bio_split(struct bio *bi, int first_sectors);
213 extern void bio_pair_release(struct bio_pair *dbio);
214
215 extern struct bio_set *bioset_create(unsigned int, unsigned int);
216 extern void bioset_free(struct bio_set *);
217 extern mempool_t *biovec_create_pool(struct bio_set *bs, int pool_entries);
218
219 extern struct bio *bio_alloc_bioset(gfp_t, int, struct bio_set *);
220 extern void bio_put(struct bio *);
221
222 extern void __bio_clone(struct bio *, struct bio *);
223 extern struct bio *bio_clone_bioset(struct bio *, gfp_t, struct bio_set *bs);
224
225 extern struct bio_set *fs_bio_set;
226
227 static inline struct bio *bio_alloc(gfp_t gfp_mask, unsigned int nr_iovecs)
228 {
229 return bio_alloc_bioset(gfp_mask, nr_iovecs, fs_bio_set);
230 }
231
232 static inline struct bio *bio_clone(struct bio *bio, gfp_t gfp_mask)
233 {
234 return bio_clone_bioset(bio, gfp_mask, fs_bio_set);
235 }
236
237 static inline struct bio *bio_kmalloc(gfp_t gfp_mask, unsigned int nr_iovecs)
238 {
239 return bio_alloc_bioset(gfp_mask, nr_iovecs, NULL);
240 }
241
242 static inline struct bio *bio_clone_kmalloc(struct bio *bio, gfp_t gfp_mask)
243 {
244 return bio_clone_bioset(bio, gfp_mask, NULL);
245
246 }
247
248 extern void bio_endio(struct bio *, int);
249 struct request_queue;
250 extern int bio_phys_segments(struct request_queue *, struct bio *);
251
252 extern void bio_advance(struct bio *, unsigned);
253
254 extern void bio_init(struct bio *);
255 extern void bio_reset(struct bio *);
256
257 extern int bio_add_page(struct bio *, struct page *, unsigned int,unsigned int);
258 extern int bio_add_pc_page(struct request_queue *, struct bio *, struct page *,
259 unsigned int, unsigned int);
260 extern int bio_get_nr_vecs(struct block_device *);
261 extern sector_t bio_sector_offset(struct bio *, unsigned short, unsigned int);
262 extern struct bio *bio_map_user(struct request_queue *, struct block_device *,
263 unsigned long, unsigned int, int, gfp_t);
264 struct sg_iovec;
265 struct rq_map_data;
266 extern struct bio *bio_map_user_iov(struct request_queue *,
267 struct block_device *,
268 struct sg_iovec *, int, int, gfp_t);
269 extern void bio_unmap_user(struct bio *);
270 extern struct bio *bio_map_kern(struct request_queue *, void *, unsigned int,
271 gfp_t);
272 extern struct bio *bio_copy_kern(struct request_queue *, void *, unsigned int,
273 gfp_t, int);
274 extern void bio_set_pages_dirty(struct bio *bio);
275 extern void bio_check_pages_dirty(struct bio *bio);
276
277 #ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
278 # error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform"
279 #endif
280 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
281 extern void bio_flush_dcache_pages(struct bio *bi);
282 #else
283 static inline void bio_flush_dcache_pages(struct bio *bi)
284 {
285 }
286 #endif
287
288 extern struct bio *bio_copy_user(struct request_queue *, struct rq_map_data *,
289 unsigned long, unsigned int, int, gfp_t);
290 extern struct bio *bio_copy_user_iov(struct request_queue *,
291 struct rq_map_data *, struct sg_iovec *,
292 int, int, gfp_t);
293 extern int bio_uncopy_user(struct bio *);
294 void zero_fill_bio(struct bio *bio);
295 extern struct bio_vec *bvec_alloc(gfp_t, int, unsigned long *, mempool_t *);
296 extern void bvec_free(mempool_t *, struct bio_vec *, unsigned int);
297 extern unsigned int bvec_nr_vecs(unsigned short idx);
298
299 #ifdef CONFIG_BLK_CGROUP
300 int bio_associate_current(struct bio *bio);
301 void bio_disassociate_task(struct bio *bio);
302 #else /* CONFIG_BLK_CGROUP */
303 static inline int bio_associate_current(struct bio *bio) { return -ENOENT; }
304 static inline void bio_disassociate_task(struct bio *bio) { }
305 #endif /* CONFIG_BLK_CGROUP */
306
307 #ifdef CONFIG_HIGHMEM
308 /*
309 * remember never ever reenable interrupts between a bvec_kmap_irq and
310 * bvec_kunmap_irq!
311 */
312 static inline char *bvec_kmap_irq(struct bio_vec *bvec, unsigned long *flags)
313 {
314 unsigned long addr;
315
316 /*
317 * might not be a highmem page, but the preempt/irq count
318 * balancing is a lot nicer this way
319 */
320 local_irq_save(*flags);
321 addr = (unsigned long) kmap_atomic(bvec->bv_page);
322
323 BUG_ON(addr & ~PAGE_MASK);
324
325 return (char *) addr + bvec->bv_offset;
326 }
327
328 static inline void bvec_kunmap_irq(char *buffer, unsigned long *flags)
329 {
330 unsigned long ptr = (unsigned long) buffer & PAGE_MASK;
331
332 kunmap_atomic((void *) ptr);
333 local_irq_restore(*flags);
334 }
335
336 #else
337 static inline char *bvec_kmap_irq(struct bio_vec *bvec, unsigned long *flags)
338 {
339 return page_address(bvec->bv_page) + bvec->bv_offset;
340 }
341
342 static inline void bvec_kunmap_irq(char *buffer, unsigned long *flags)
343 {
344 *flags = 0;
345 }
346 #endif
347
348 static inline char *__bio_kmap_irq(struct bio *bio, unsigned short idx,
349 unsigned long *flags)
350 {
351 return bvec_kmap_irq(bio_iovec_idx(bio, idx), flags);
352 }
353 #define __bio_kunmap_irq(buf, flags) bvec_kunmap_irq(buf, flags)
354
355 #define bio_kmap_irq(bio, flags) \
356 __bio_kmap_irq((bio), (bio)->bi_idx, (flags))
357 #define bio_kunmap_irq(buf,flags) __bio_kunmap_irq(buf, flags)
358
359 /*
360 * Check whether this bio carries any data or not. A NULL bio is allowed.
361 */
362 static inline bool bio_has_data(struct bio *bio)
363 {
364 if (bio && bio->bi_vcnt)
365 return true;
366
367 return false;
368 }
369
370 static inline bool bio_is_rw(struct bio *bio)
371 {
372 if (!bio_has_data(bio))
373 return false;
374
375 if (bio->bi_rw & REQ_WRITE_SAME)
376 return false;
377
378 return true;
379 }
380
381 static inline bool bio_mergeable(struct bio *bio)
382 {
383 if (bio->bi_rw & REQ_NOMERGE_FLAGS)
384 return false;
385
386 return true;
387 }
388
389 /*
390 * BIO list management for use by remapping drivers (e.g. DM or MD) and loop.
391 *
392 * A bio_list anchors a singly-linked list of bios chained through the bi_next
393 * member of the bio. The bio_list also caches the last list member to allow
394 * fast access to the tail.
395 */
396 struct bio_list {
397 struct bio *head;
398 struct bio *tail;
399 };
400
401 static inline int bio_list_empty(const struct bio_list *bl)
402 {
403 return bl->head == NULL;
404 }
405
406 static inline void bio_list_init(struct bio_list *bl)
407 {
408 bl->head = bl->tail = NULL;
409 }
410
411 #define bio_list_for_each(bio, bl) \
412 for (bio = (bl)->head; bio; bio = bio->bi_next)
413
414 static inline unsigned bio_list_size(const struct bio_list *bl)
415 {
416 unsigned sz = 0;
417 struct bio *bio;
418
419 bio_list_for_each(bio, bl)
420 sz++;
421
422 return sz;
423 }
424
425 static inline void bio_list_add(struct bio_list *bl, struct bio *bio)
426 {
427 bio->bi_next = NULL;
428
429 if (bl->tail)
430 bl->tail->bi_next = bio;
431 else
432 bl->head = bio;
433
434 bl->tail = bio;
435 }
436
437 static inline void bio_list_add_head(struct bio_list *bl, struct bio *bio)
438 {
439 bio->bi_next = bl->head;
440
441 bl->head = bio;
442
443 if (!bl->tail)
444 bl->tail = bio;
445 }
446
447 static inline void bio_list_merge(struct bio_list *bl, struct bio_list *bl2)
448 {
449 if (!bl2->head)
450 return;
451
452 if (bl->tail)
453 bl->tail->bi_next = bl2->head;
454 else
455 bl->head = bl2->head;
456
457 bl->tail = bl2->tail;
458 }
459
460 static inline void bio_list_merge_head(struct bio_list *bl,
461 struct bio_list *bl2)
462 {
463 if (!bl2->head)
464 return;
465
466 if (bl->head)
467 bl2->tail->bi_next = bl->head;
468 else
469 bl->tail = bl2->tail;
470
471 bl->head = bl2->head;
472 }
473
474 static inline struct bio *bio_list_peek(struct bio_list *bl)
475 {
476 return bl->head;
477 }
478
479 static inline struct bio *bio_list_pop(struct bio_list *bl)
480 {
481 struct bio *bio = bl->head;
482
483 if (bio) {
484 bl->head = bl->head->bi_next;
485 if (!bl->head)
486 bl->tail = NULL;
487
488 bio->bi_next = NULL;
489 }
490
491 return bio;
492 }
493
494 static inline struct bio *bio_list_get(struct bio_list *bl)
495 {
496 struct bio *bio = bl->head;
497
498 bl->head = bl->tail = NULL;
499
500 return bio;
501 }
502
503 /*
504 * bio_set is used to allow other portions of the IO system to
505 * allocate their own private memory pools for bio and iovec structures.
506 * These memory pools in turn all allocate from the bio_slab
507 * and the bvec_slabs[].
508 */
509 #define BIO_POOL_SIZE 2
510 #define BIOVEC_NR_POOLS 6
511 #define BIOVEC_MAX_IDX (BIOVEC_NR_POOLS - 1)
512
513 struct bio_set {
514 struct kmem_cache *bio_slab;
515 unsigned int front_pad;
516
517 mempool_t *bio_pool;
518 mempool_t *bvec_pool;
519 #if defined(CONFIG_BLK_DEV_INTEGRITY)
520 mempool_t *bio_integrity_pool;
521 mempool_t *bvec_integrity_pool;
522 #endif
523
524 /*
525 * Deadlock avoidance for stacking block drivers: see comments in
526 * bio_alloc_bioset() for details
527 */
528 spinlock_t rescue_lock;
529 struct bio_list rescue_list;
530 struct work_struct rescue_work;
531 struct workqueue_struct *rescue_workqueue;
532 };
533
534 struct biovec_slab {
535 int nr_vecs;
536 char *name;
537 struct kmem_cache *slab;
538 };
539
540 /*
541 * a small number of entries is fine, not going to be performance critical.
542 * basically we just need to survive
543 */
544 #define BIO_SPLIT_ENTRIES 2
545
546 #if defined(CONFIG_BLK_DEV_INTEGRITY)
547
548 #define bip_vec_idx(bip, idx) (&(bip->bip_vec[(idx)]))
549 #define bip_vec(bip) bip_vec_idx(bip, 0)
550
551 #define __bip_for_each_vec(bvl, bip, i, start_idx) \
552 for (bvl = bip_vec_idx((bip), (start_idx)), i = (start_idx); \
553 i < (bip)->bip_vcnt; \
554 bvl++, i++)
555
556 #define bip_for_each_vec(bvl, bip, i) \
557 __bip_for_each_vec(bvl, bip, i, (bip)->bip_idx)
558
559 #define bio_for_each_integrity_vec(_bvl, _bio, _iter) \
560 for_each_bio(_bio) \
561 bip_for_each_vec(_bvl, _bio->bi_integrity, _iter)
562
563 #define bio_integrity(bio) (bio->bi_integrity != NULL)
564
565 extern struct bio_integrity_payload *bio_integrity_alloc(struct bio *, gfp_t, unsigned int);
566 extern void bio_integrity_free(struct bio *);
567 extern int bio_integrity_add_page(struct bio *, struct page *, unsigned int, unsigned int);
568 extern int bio_integrity_enabled(struct bio *bio);
569 extern int bio_integrity_set_tag(struct bio *, void *, unsigned int);
570 extern int bio_integrity_get_tag(struct bio *, void *, unsigned int);
571 extern int bio_integrity_prep(struct bio *);
572 extern void bio_integrity_endio(struct bio *, int);
573 extern void bio_integrity_advance(struct bio *, unsigned int);
574 extern void bio_integrity_trim(struct bio *, unsigned int, unsigned int);
575 extern void bio_integrity_split(struct bio *, struct bio_pair *, int);
576 extern int bio_integrity_clone(struct bio *, struct bio *, gfp_t);
577 extern int bioset_integrity_create(struct bio_set *, int);
578 extern void bioset_integrity_free(struct bio_set *);
579 extern void bio_integrity_init(void);
580
581 #else /* CONFIG_BLK_DEV_INTEGRITY */
582
583 static inline int bio_integrity(struct bio *bio)
584 {
585 return 0;
586 }
587
588 static inline int bio_integrity_enabled(struct bio *bio)
589 {
590 return 0;
591 }
592
593 static inline int bioset_integrity_create(struct bio_set *bs, int pool_size)
594 {
595 return 0;
596 }
597
598 static inline void bioset_integrity_free (struct bio_set *bs)
599 {
600 return;
601 }
602
603 static inline int bio_integrity_prep(struct bio *bio)
604 {
605 return 0;
606 }
607
608 static inline void bio_integrity_free(struct bio *bio)
609 {
610 return;
611 }
612
613 static inline int bio_integrity_clone(struct bio *bio, struct bio *bio_src,
614 gfp_t gfp_mask)
615 {
616 return 0;
617 }
618
619 static inline void bio_integrity_split(struct bio *bio, struct bio_pair *bp,
620 int sectors)
621 {
622 return;
623 }
624
625 static inline void bio_integrity_advance(struct bio *bio,
626 unsigned int bytes_done)
627 {
628 return;
629 }
630
631 static inline void bio_integrity_trim(struct bio *bio, unsigned int offset,
632 unsigned int sectors)
633 {
634 return;
635 }
636
637 static inline void bio_integrity_init(void)
638 {
639 return;
640 }
641
642 #endif /* CONFIG_BLK_DEV_INTEGRITY */
643
644 #endif /* CONFIG_BLOCK */
645 #endif /* __LINUX_BIO_H */