4 * Copyright (C) 2001 Jens Axboe <axboe@suse.de>
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.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
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-
23 #include <linux/highmem.h>
24 #include <linux/mempool.h>
25 #include <linux/ioprio.h>
26 #include <linux/bug.h>
32 /* struct bio, bio_vec and BIO_* flags are defined in blk_types.h */
33 #include <linux/blk_types.h>
38 #define BIO_BUG_ON BUG_ON
43 #define BIO_MAX_PAGES 256
45 #define bio_prio(bio) (bio)->bi_ioprio
46 #define bio_set_prio(bio, prio) ((bio)->bi_ioprio = prio)
48 #define bio_iter_iovec(bio, iter) \
49 bvec_iter_bvec((bio)->bi_io_vec, (iter))
51 #define bio_iter_page(bio, iter) \
52 bvec_iter_page((bio)->bi_io_vec, (iter))
53 #define bio_iter_len(bio, iter) \
54 bvec_iter_len((bio)->bi_io_vec, (iter))
55 #define bio_iter_offset(bio, iter) \
56 bvec_iter_offset((bio)->bi_io_vec, (iter))
58 #define bio_page(bio) bio_iter_page((bio), (bio)->bi_iter)
59 #define bio_offset(bio) bio_iter_offset((bio), (bio)->bi_iter)
60 #define bio_iovec(bio) bio_iter_iovec((bio), (bio)->bi_iter)
62 #define bio_multiple_segments(bio) \
63 ((bio)->bi_iter.bi_size != bio_iovec(bio).bv_len)
64 #define bio_sectors(bio) ((bio)->bi_iter.bi_size >> 9)
65 #define bio_end_sector(bio) ((bio)->bi_iter.bi_sector + bio_sectors((bio)))
68 * Check whether this bio carries any data or not. A NULL bio is allowed.
70 static inline bool bio_has_data(struct bio
*bio
)
73 bio
->bi_iter
.bi_size
&&
74 bio_op(bio
) != REQ_OP_DISCARD
)
80 static inline bool bio_no_advance_iter(struct bio
*bio
)
82 return bio_op(bio
) == REQ_OP_DISCARD
|| bio_op(bio
) == REQ_OP_WRITE_SAME
;
85 static inline bool bio_is_rw(struct bio
*bio
)
87 if (!bio_has_data(bio
))
90 if (bio_no_advance_iter(bio
))
96 static inline bool bio_mergeable(struct bio
*bio
)
98 if (bio
->bi_rw
& REQ_NOMERGE_FLAGS
)
104 static inline unsigned int bio_cur_bytes(struct bio
*bio
)
106 if (bio_has_data(bio
))
107 return bio_iovec(bio
).bv_len
;
108 else /* dataless requests such as discard */
109 return bio
->bi_iter
.bi_size
;
112 static inline void *bio_data(struct bio
*bio
)
114 if (bio_has_data(bio
))
115 return page_address(bio_page(bio
)) + bio_offset(bio
);
123 #define bio_to_phys(bio) (page_to_phys(bio_page((bio))) + (unsigned long) bio_offset((bio)))
124 #define bvec_to_phys(bv) (page_to_phys((bv)->bv_page) + (unsigned long) (bv)->bv_offset)
127 * queues that have highmem support enabled may still need to revert to
128 * PIO transfers occasionally and thus map high pages temporarily. For
129 * permanent PIO fall back, user is probably better off disabling highmem
130 * I/O completely on that queue (see ide-dma for example)
132 #define __bio_kmap_atomic(bio, iter) \
133 (kmap_atomic(bio_iter_iovec((bio), (iter)).bv_page) + \
134 bio_iter_iovec((bio), (iter)).bv_offset)
136 #define __bio_kunmap_atomic(addr) kunmap_atomic(addr)
142 /* Default implementation of BIOVEC_PHYS_MERGEABLE */
143 #define __BIOVEC_PHYS_MERGEABLE(vec1, vec2) \
144 ((bvec_to_phys((vec1)) + (vec1)->bv_len) == bvec_to_phys((vec2)))
147 * allow arch override, for eg virtualized architectures (put in asm/io.h)
149 #ifndef BIOVEC_PHYS_MERGEABLE
150 #define BIOVEC_PHYS_MERGEABLE(vec1, vec2) \
151 __BIOVEC_PHYS_MERGEABLE(vec1, vec2)
154 #define __BIO_SEG_BOUNDARY(addr1, addr2, mask) \
155 (((addr1) | (mask)) == (((addr2) - 1) | (mask)))
156 #define BIOVEC_SEG_BOUNDARY(q, b1, b2) \
157 __BIO_SEG_BOUNDARY(bvec_to_phys((b1)), bvec_to_phys((b2)) + (b2)->bv_len, queue_segment_boundary((q)))
160 * drivers should _never_ use the all version - the bio may have been split
161 * before it got to the driver and the driver won't own all of it
163 #define bio_for_each_segment_all(bvl, bio, i) \
164 for (i = 0, bvl = (bio)->bi_io_vec; i < (bio)->bi_vcnt; i++, bvl++)
166 static inline void bio_advance_iter(struct bio
*bio
, struct bvec_iter
*iter
,
169 iter
->bi_sector
+= bytes
>> 9;
171 if (bio_no_advance_iter(bio
))
172 iter
->bi_size
-= bytes
;
174 bvec_iter_advance(bio
->bi_io_vec
, iter
, bytes
);
177 #define __bio_for_each_segment(bvl, bio, iter, start) \
178 for (iter = (start); \
180 ((bvl = bio_iter_iovec((bio), (iter))), 1); \
181 bio_advance_iter((bio), &(iter), (bvl).bv_len))
183 #define bio_for_each_segment(bvl, bio, iter) \
184 __bio_for_each_segment(bvl, bio, iter, (bio)->bi_iter)
186 #define bio_iter_last(bvec, iter) ((iter).bi_size == (bvec).bv_len)
188 static inline unsigned bio_segments(struct bio
*bio
)
192 struct bvec_iter iter
;
195 * We special case discard/write same, because they interpret bi_size
199 if (bio_op(bio
) == REQ_OP_DISCARD
)
202 if (bio_op(bio
) == REQ_OP_WRITE_SAME
)
205 bio_for_each_segment(bv
, bio
, iter
)
212 * get a reference to a bio, so it won't disappear. the intended use is
216 * submit_bio(rw, bio);
217 * if (bio->bi_flags ...)
221 * without the bio_get(), it could potentially complete I/O before submit_bio
222 * returns. and then bio would be freed memory when if (bio->bi_flags ...)
225 static inline void bio_get(struct bio
*bio
)
227 bio
->bi_flags
|= (1 << BIO_REFFED
);
228 smp_mb__before_atomic();
229 atomic_inc(&bio
->__bi_cnt
);
232 static inline void bio_cnt_set(struct bio
*bio
, unsigned int count
)
235 bio
->bi_flags
|= (1 << BIO_REFFED
);
236 smp_mb__before_atomic();
238 atomic_set(&bio
->__bi_cnt
, count
);
241 static inline bool bio_flagged(struct bio
*bio
, unsigned int bit
)
243 return (bio
->bi_flags
& (1U << bit
)) != 0;
246 static inline void bio_set_flag(struct bio
*bio
, unsigned int bit
)
248 bio
->bi_flags
|= (1U << bit
);
251 static inline void bio_clear_flag(struct bio
*bio
, unsigned int bit
)
253 bio
->bi_flags
&= ~(1U << bit
);
256 static inline void bio_get_first_bvec(struct bio
*bio
, struct bio_vec
*bv
)
258 *bv
= bio_iovec(bio
);
261 static inline void bio_get_last_bvec(struct bio
*bio
, struct bio_vec
*bv
)
263 struct bvec_iter iter
= bio
->bi_iter
;
266 if (unlikely(!bio_multiple_segments(bio
))) {
267 *bv
= bio_iovec(bio
);
271 bio_advance_iter(bio
, &iter
, iter
.bi_size
);
273 if (!iter
.bi_bvec_done
)
274 idx
= iter
.bi_idx
- 1;
275 else /* in the middle of bvec */
278 *bv
= bio
->bi_io_vec
[idx
];
281 * iter.bi_bvec_done records actual length of the last bvec
282 * if this bio ends in the middle of one io vector
284 if (iter
.bi_bvec_done
)
285 bv
->bv_len
= iter
.bi_bvec_done
;
289 BIP_BLOCK_INTEGRITY
= 1 << 0, /* block layer owns integrity data */
290 BIP_MAPPED_INTEGRITY
= 1 << 1, /* ref tag has been remapped */
291 BIP_CTRL_NOCHECK
= 1 << 2, /* disable HBA integrity checking */
292 BIP_DISK_NOCHECK
= 1 << 3, /* disable disk integrity checking */
293 BIP_IP_CHECKSUM
= 1 << 4, /* IP checksum */
297 * bio integrity payload
299 struct bio_integrity_payload
{
300 struct bio
*bip_bio
; /* parent bio */
302 struct bvec_iter bip_iter
;
304 bio_end_io_t
*bip_end_io
; /* saved I/O completion fn */
306 unsigned short bip_slab
; /* slab the bip came from */
307 unsigned short bip_vcnt
; /* # of integrity bio_vecs */
308 unsigned short bip_max_vcnt
; /* integrity bio_vec slots */
309 unsigned short bip_flags
; /* control flags */
311 struct work_struct bip_work
; /* I/O completion */
313 struct bio_vec
*bip_vec
;
314 struct bio_vec bip_inline_vecs
[0];/* embedded bvec array */
317 #if defined(CONFIG_BLK_DEV_INTEGRITY)
319 static inline struct bio_integrity_payload
*bio_integrity(struct bio
*bio
)
321 if (bio
->bi_rw
& REQ_INTEGRITY
)
322 return bio
->bi_integrity
;
327 static inline bool bio_integrity_flagged(struct bio
*bio
, enum bip_flags flag
)
329 struct bio_integrity_payload
*bip
= bio_integrity(bio
);
332 return bip
->bip_flags
& flag
;
337 static inline sector_t
bip_get_seed(struct bio_integrity_payload
*bip
)
339 return bip
->bip_iter
.bi_sector
;
342 static inline void bip_set_seed(struct bio_integrity_payload
*bip
,
345 bip
->bip_iter
.bi_sector
= seed
;
348 #endif /* CONFIG_BLK_DEV_INTEGRITY */
350 extern void bio_trim(struct bio
*bio
, int offset
, int size
);
351 extern struct bio
*bio_split(struct bio
*bio
, int sectors
,
352 gfp_t gfp
, struct bio_set
*bs
);
355 * bio_next_split - get next @sectors from a bio, splitting if necessary
357 * @sectors: number of sectors to split from the front of @bio
359 * @bs: bio set to allocate from
361 * Returns a bio representing the next @sectors of @bio - if the bio is smaller
362 * than @sectors, returns the original bio unchanged.
364 static inline struct bio
*bio_next_split(struct bio
*bio
, int sectors
,
365 gfp_t gfp
, struct bio_set
*bs
)
367 if (sectors
>= bio_sectors(bio
))
370 return bio_split(bio
, sectors
, gfp
, bs
);
373 extern struct bio_set
*bioset_create(unsigned int, unsigned int);
374 extern struct bio_set
*bioset_create_nobvec(unsigned int, unsigned int);
375 extern void bioset_free(struct bio_set
*);
376 extern mempool_t
*biovec_create_pool(int pool_entries
);
378 extern struct bio
*bio_alloc_bioset(gfp_t
, int, struct bio_set
*);
379 extern void bio_put(struct bio
*);
381 extern void __bio_clone_fast(struct bio
*, struct bio
*);
382 extern struct bio
*bio_clone_fast(struct bio
*, gfp_t
, struct bio_set
*);
383 extern struct bio
*bio_clone_bioset(struct bio
*, gfp_t
, struct bio_set
*bs
);
385 extern struct bio_set
*fs_bio_set
;
387 static inline struct bio
*bio_alloc(gfp_t gfp_mask
, unsigned int nr_iovecs
)
389 return bio_alloc_bioset(gfp_mask
, nr_iovecs
, fs_bio_set
);
392 static inline struct bio
*bio_clone(struct bio
*bio
, gfp_t gfp_mask
)
394 return bio_clone_bioset(bio
, gfp_mask
, fs_bio_set
);
397 static inline struct bio
*bio_kmalloc(gfp_t gfp_mask
, unsigned int nr_iovecs
)
399 return bio_alloc_bioset(gfp_mask
, nr_iovecs
, NULL
);
402 static inline struct bio
*bio_clone_kmalloc(struct bio
*bio
, gfp_t gfp_mask
)
404 return bio_clone_bioset(bio
, gfp_mask
, NULL
);
408 extern void bio_endio(struct bio
*);
410 static inline void bio_io_error(struct bio
*bio
)
412 bio
->bi_error
= -EIO
;
416 struct request_queue
;
417 extern int bio_phys_segments(struct request_queue
*, struct bio
*);
419 extern int submit_bio_wait(struct bio
*bio
);
420 extern void bio_advance(struct bio
*, unsigned);
422 extern void bio_init(struct bio
*);
423 extern void bio_reset(struct bio
*);
424 void bio_chain(struct bio
*, struct bio
*);
426 extern int bio_add_page(struct bio
*, struct page
*, unsigned int,unsigned int);
427 extern int bio_add_pc_page(struct request_queue
*, struct bio
*, struct page
*,
428 unsigned int, unsigned int);
430 extern struct bio
*bio_map_user_iov(struct request_queue
*,
431 const struct iov_iter
*, gfp_t
);
432 extern void bio_unmap_user(struct bio
*);
433 extern struct bio
*bio_map_kern(struct request_queue
*, void *, unsigned int,
435 extern struct bio
*bio_copy_kern(struct request_queue
*, void *, unsigned int,
437 extern void bio_set_pages_dirty(struct bio
*bio
);
438 extern void bio_check_pages_dirty(struct bio
*bio
);
440 void generic_start_io_acct(int rw
, unsigned long sectors
,
441 struct hd_struct
*part
);
442 void generic_end_io_acct(int rw
, struct hd_struct
*part
,
443 unsigned long start_time
);
445 #ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
446 # error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform"
448 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
449 extern void bio_flush_dcache_pages(struct bio
*bi
);
451 static inline void bio_flush_dcache_pages(struct bio
*bi
)
456 extern void bio_copy_data(struct bio
*dst
, struct bio
*src
);
457 extern int bio_alloc_pages(struct bio
*bio
, gfp_t gfp
);
459 extern struct bio
*bio_copy_user_iov(struct request_queue
*,
460 struct rq_map_data
*,
461 const struct iov_iter
*,
463 extern int bio_uncopy_user(struct bio
*);
464 void zero_fill_bio(struct bio
*bio
);
465 extern struct bio_vec
*bvec_alloc(gfp_t
, int, unsigned long *, mempool_t
*);
466 extern void bvec_free(mempool_t
*, struct bio_vec
*, unsigned int);
467 extern unsigned int bvec_nr_vecs(unsigned short idx
);
469 #ifdef CONFIG_BLK_CGROUP
470 int bio_associate_blkcg(struct bio
*bio
, struct cgroup_subsys_state
*blkcg_css
);
471 int bio_associate_current(struct bio
*bio
);
472 void bio_disassociate_task(struct bio
*bio
);
473 #else /* CONFIG_BLK_CGROUP */
474 static inline int bio_associate_blkcg(struct bio
*bio
,
475 struct cgroup_subsys_state
*blkcg_css
) { return 0; }
476 static inline int bio_associate_current(struct bio
*bio
) { return -ENOENT
; }
477 static inline void bio_disassociate_task(struct bio
*bio
) { }
478 #endif /* CONFIG_BLK_CGROUP */
480 #ifdef CONFIG_HIGHMEM
482 * remember never ever reenable interrupts between a bvec_kmap_irq and
485 static inline char *bvec_kmap_irq(struct bio_vec
*bvec
, unsigned long *flags
)
490 * might not be a highmem page, but the preempt/irq count
491 * balancing is a lot nicer this way
493 local_irq_save(*flags
);
494 addr
= (unsigned long) kmap_atomic(bvec
->bv_page
);
496 BUG_ON(addr
& ~PAGE_MASK
);
498 return (char *) addr
+ bvec
->bv_offset
;
501 static inline void bvec_kunmap_irq(char *buffer
, unsigned long *flags
)
503 unsigned long ptr
= (unsigned long) buffer
& PAGE_MASK
;
505 kunmap_atomic((void *) ptr
);
506 local_irq_restore(*flags
);
510 static inline char *bvec_kmap_irq(struct bio_vec
*bvec
, unsigned long *flags
)
512 return page_address(bvec
->bv_page
) + bvec
->bv_offset
;
515 static inline void bvec_kunmap_irq(char *buffer
, unsigned long *flags
)
521 static inline char *__bio_kmap_irq(struct bio
*bio
, struct bvec_iter iter
,
522 unsigned long *flags
)
524 return bvec_kmap_irq(&bio_iter_iovec(bio
, iter
), flags
);
526 #define __bio_kunmap_irq(buf, flags) bvec_kunmap_irq(buf, flags)
528 #define bio_kmap_irq(bio, flags) \
529 __bio_kmap_irq((bio), (bio)->bi_iter, (flags))
530 #define bio_kunmap_irq(buf,flags) __bio_kunmap_irq(buf, flags)
533 * BIO list management for use by remapping drivers (e.g. DM or MD) and loop.
535 * A bio_list anchors a singly-linked list of bios chained through the bi_next
536 * member of the bio. The bio_list also caches the last list member to allow
537 * fast access to the tail.
544 static inline int bio_list_empty(const struct bio_list
*bl
)
546 return bl
->head
== NULL
;
549 static inline void bio_list_init(struct bio_list
*bl
)
551 bl
->head
= bl
->tail
= NULL
;
554 #define BIO_EMPTY_LIST { NULL, NULL }
556 #define bio_list_for_each(bio, bl) \
557 for (bio = (bl)->head; bio; bio = bio->bi_next)
559 static inline unsigned bio_list_size(const struct bio_list
*bl
)
564 bio_list_for_each(bio
, bl
)
570 static inline void bio_list_add(struct bio_list
*bl
, struct bio
*bio
)
575 bl
->tail
->bi_next
= bio
;
582 static inline void bio_list_add_head(struct bio_list
*bl
, struct bio
*bio
)
584 bio
->bi_next
= bl
->head
;
592 static inline void bio_list_merge(struct bio_list
*bl
, struct bio_list
*bl2
)
598 bl
->tail
->bi_next
= bl2
->head
;
600 bl
->head
= bl2
->head
;
602 bl
->tail
= bl2
->tail
;
605 static inline void bio_list_merge_head(struct bio_list
*bl
,
606 struct bio_list
*bl2
)
612 bl2
->tail
->bi_next
= bl
->head
;
614 bl
->tail
= bl2
->tail
;
616 bl
->head
= bl2
->head
;
619 static inline struct bio
*bio_list_peek(struct bio_list
*bl
)
624 static inline struct bio
*bio_list_pop(struct bio_list
*bl
)
626 struct bio
*bio
= bl
->head
;
629 bl
->head
= bl
->head
->bi_next
;
639 static inline struct bio
*bio_list_get(struct bio_list
*bl
)
641 struct bio
*bio
= bl
->head
;
643 bl
->head
= bl
->tail
= NULL
;
649 * Increment chain count for the bio. Make sure the CHAIN flag update
650 * is visible before the raised count.
652 static inline void bio_inc_remaining(struct bio
*bio
)
654 bio_set_flag(bio
, BIO_CHAIN
);
655 smp_mb__before_atomic();
656 atomic_inc(&bio
->__bi_remaining
);
660 * bio_set is used to allow other portions of the IO system to
661 * allocate their own private memory pools for bio and iovec structures.
662 * These memory pools in turn all allocate from the bio_slab
663 * and the bvec_slabs[].
665 #define BIO_POOL_SIZE 2
668 struct kmem_cache
*bio_slab
;
669 unsigned int front_pad
;
672 mempool_t
*bvec_pool
;
673 #if defined(CONFIG_BLK_DEV_INTEGRITY)
674 mempool_t
*bio_integrity_pool
;
675 mempool_t
*bvec_integrity_pool
;
679 * Deadlock avoidance for stacking block drivers: see comments in
680 * bio_alloc_bioset() for details
682 spinlock_t rescue_lock
;
683 struct bio_list rescue_list
;
684 struct work_struct rescue_work
;
685 struct workqueue_struct
*rescue_workqueue
;
691 struct kmem_cache
*slab
;
695 * a small number of entries is fine, not going to be performance critical.
696 * basically we just need to survive
698 #define BIO_SPLIT_ENTRIES 2
700 #if defined(CONFIG_BLK_DEV_INTEGRITY)
702 #define bip_for_each_vec(bvl, bip, iter) \
703 for_each_bvec(bvl, (bip)->bip_vec, iter, (bip)->bip_iter)
705 #define bio_for_each_integrity_vec(_bvl, _bio, _iter) \
707 bip_for_each_vec(_bvl, _bio->bi_integrity, _iter)
709 extern struct bio_integrity_payload
*bio_integrity_alloc(struct bio
*, gfp_t
, unsigned int);
710 extern void bio_integrity_free(struct bio
*);
711 extern int bio_integrity_add_page(struct bio
*, struct page
*, unsigned int, unsigned int);
712 extern bool bio_integrity_enabled(struct bio
*bio
);
713 extern int bio_integrity_prep(struct bio
*);
714 extern void bio_integrity_endio(struct bio
*);
715 extern void bio_integrity_advance(struct bio
*, unsigned int);
716 extern void bio_integrity_trim(struct bio
*, unsigned int, unsigned int);
717 extern int bio_integrity_clone(struct bio
*, struct bio
*, gfp_t
);
718 extern int bioset_integrity_create(struct bio_set
*, int);
719 extern void bioset_integrity_free(struct bio_set
*);
720 extern void bio_integrity_init(void);
722 #else /* CONFIG_BLK_DEV_INTEGRITY */
724 static inline void *bio_integrity(struct bio
*bio
)
729 static inline bool bio_integrity_enabled(struct bio
*bio
)
734 static inline int bioset_integrity_create(struct bio_set
*bs
, int pool_size
)
739 static inline void bioset_integrity_free (struct bio_set
*bs
)
744 static inline int bio_integrity_prep(struct bio
*bio
)
749 static inline void bio_integrity_free(struct bio
*bio
)
754 static inline int bio_integrity_clone(struct bio
*bio
, struct bio
*bio_src
,
760 static inline void bio_integrity_advance(struct bio
*bio
,
761 unsigned int bytes_done
)
766 static inline void bio_integrity_trim(struct bio
*bio
, unsigned int offset
,
767 unsigned int sectors
)
772 static inline void bio_integrity_init(void)
777 static inline bool bio_integrity_flagged(struct bio
*bio
, enum bip_flags flag
)
782 static inline void *bio_integrity_alloc(struct bio
* bio
, gfp_t gfp
,
785 return ERR_PTR(-EINVAL
);
788 static inline int bio_integrity_add_page(struct bio
*bio
, struct page
*page
,
789 unsigned int len
, unsigned int offset
)
794 #endif /* CONFIG_BLK_DEV_INTEGRITY */
796 #endif /* CONFIG_BLOCK */
797 #endif /* __LINUX_BIO_H */
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