1 /* SPDX-License-Identifier: GPL-2.0 */
3 * Copyright (C) 2001 Jens Axboe <axboe@suse.de>
8 #include <linux/highmem.h>
9 #include <linux/mempool.h>
10 #include <linux/ioprio.h>
13 /* struct bio, bio_vec and BIO_* flags are defined in blk_types.h */
14 #include <linux/blk_types.h>
19 #define BIO_BUG_ON BUG_ON
24 #define BIO_MAX_PAGES 256
26 #define bio_prio(bio) (bio)->bi_ioprio
27 #define bio_set_prio(bio, prio) ((bio)->bi_ioprio = prio)
29 #define bio_iter_iovec(bio, iter) \
30 bvec_iter_bvec((bio)->bi_io_vec, (iter))
32 #define bio_iter_page(bio, iter) \
33 bvec_iter_page((bio)->bi_io_vec, (iter))
34 #define bio_iter_len(bio, iter) \
35 bvec_iter_len((bio)->bi_io_vec, (iter))
36 #define bio_iter_offset(bio, iter) \
37 bvec_iter_offset((bio)->bi_io_vec, (iter))
39 #define bio_page(bio) bio_iter_page((bio), (bio)->bi_iter)
40 #define bio_offset(bio) bio_iter_offset((bio), (bio)->bi_iter)
41 #define bio_iovec(bio) bio_iter_iovec((bio), (bio)->bi_iter)
43 #define bio_multiple_segments(bio) \
44 ((bio)->bi_iter.bi_size != bio_iovec(bio).bv_len)
46 #define bvec_iter_sectors(iter) ((iter).bi_size >> 9)
47 #define bvec_iter_end_sector(iter) ((iter).bi_sector + bvec_iter_sectors((iter)))
49 #define bio_sectors(bio) bvec_iter_sectors((bio)->bi_iter)
50 #define bio_end_sector(bio) bvec_iter_end_sector((bio)->bi_iter)
53 * Return the data direction, READ or WRITE.
55 #define bio_data_dir(bio) \
56 (op_is_write(bio_op(bio)) ? WRITE : READ)
59 * Check whether this bio carries any data or not. A NULL bio is allowed.
61 static inline bool bio_has_data(struct bio
*bio
)
64 bio
->bi_iter
.bi_size
&&
65 bio_op(bio
) != REQ_OP_DISCARD
&&
66 bio_op(bio
) != REQ_OP_SECURE_ERASE
&&
67 bio_op(bio
) != REQ_OP_WRITE_ZEROES
)
73 static inline bool bio_no_advance_iter(struct bio
*bio
)
75 return bio_op(bio
) == REQ_OP_DISCARD
||
76 bio_op(bio
) == REQ_OP_SECURE_ERASE
||
77 bio_op(bio
) == REQ_OP_WRITE_SAME
||
78 bio_op(bio
) == REQ_OP_WRITE_ZEROES
;
81 static inline bool bio_mergeable(struct bio
*bio
)
83 if (bio
->bi_opf
& REQ_NOMERGE_FLAGS
)
89 static inline unsigned int bio_cur_bytes(struct bio
*bio
)
91 if (bio_has_data(bio
))
92 return bio_iovec(bio
).bv_len
;
93 else /* dataless requests such as discard */
94 return bio
->bi_iter
.bi_size
;
97 static inline void *bio_data(struct bio
*bio
)
99 if (bio_has_data(bio
))
100 return page_address(bio_page(bio
)) + bio_offset(bio
);
106 * bio_full - check if the bio is full
108 * @len: length of one segment to be added
110 * Return true if @bio is full and one segment with @len bytes can't be
111 * added to the bio, otherwise return false
113 static inline bool bio_full(struct bio
*bio
, unsigned len
)
115 if (bio
->bi_vcnt
>= bio
->bi_max_vecs
)
118 if (bio
->bi_iter
.bi_size
> UINT_MAX
- len
)
124 static inline bool bio_next_segment(const struct bio
*bio
,
125 struct bvec_iter_all
*iter
)
127 if (iter
->idx
>= bio
->bi_vcnt
)
130 bvec_advance(&bio
->bi_io_vec
[iter
->idx
], iter
);
135 * drivers should _never_ use the all version - the bio may have been split
136 * before it got to the driver and the driver won't own all of it
138 #define bio_for_each_segment_all(bvl, bio, iter) \
139 for (bvl = bvec_init_iter_all(&iter); bio_next_segment((bio), &iter); )
141 static inline void bio_advance_iter(struct bio
*bio
, struct bvec_iter
*iter
,
144 iter
->bi_sector
+= bytes
>> 9;
146 if (bio_no_advance_iter(bio
))
147 iter
->bi_size
-= bytes
;
149 bvec_iter_advance(bio
->bi_io_vec
, iter
, bytes
);
150 /* TODO: It is reasonable to complete bio with error here. */
153 #define __bio_for_each_segment(bvl, bio, iter, start) \
154 for (iter = (start); \
156 ((bvl = bio_iter_iovec((bio), (iter))), 1); \
157 bio_advance_iter((bio), &(iter), (bvl).bv_len))
159 #define bio_for_each_segment(bvl, bio, iter) \
160 __bio_for_each_segment(bvl, bio, iter, (bio)->bi_iter)
162 #define __bio_for_each_bvec(bvl, bio, iter, start) \
163 for (iter = (start); \
165 ((bvl = mp_bvec_iter_bvec((bio)->bi_io_vec, (iter))), 1); \
166 bio_advance_iter((bio), &(iter), (bvl).bv_len))
168 /* iterate over multi-page bvec */
169 #define bio_for_each_bvec(bvl, bio, iter) \
170 __bio_for_each_bvec(bvl, bio, iter, (bio)->bi_iter)
172 #define bio_iter_last(bvec, iter) ((iter).bi_size == (bvec).bv_len)
174 static inline unsigned bio_segments(struct bio
*bio
)
178 struct bvec_iter iter
;
181 * We special case discard/write same/write zeroes, because they
182 * interpret bi_size differently:
185 switch (bio_op(bio
)) {
187 case REQ_OP_SECURE_ERASE
:
188 case REQ_OP_WRITE_ZEROES
:
190 case REQ_OP_WRITE_SAME
:
196 bio_for_each_segment(bv
, bio
, iter
)
203 * get a reference to a bio, so it won't disappear. the intended use is
207 * submit_bio(rw, bio);
208 * if (bio->bi_flags ...)
212 * without the bio_get(), it could potentially complete I/O before submit_bio
213 * returns. and then bio would be freed memory when if (bio->bi_flags ...)
216 static inline void bio_get(struct bio
*bio
)
218 bio
->bi_flags
|= (1 << BIO_REFFED
);
219 smp_mb__before_atomic();
220 atomic_inc(&bio
->__bi_cnt
);
223 static inline void bio_cnt_set(struct bio
*bio
, unsigned int count
)
226 bio
->bi_flags
|= (1 << BIO_REFFED
);
229 atomic_set(&bio
->__bi_cnt
, count
);
232 static inline bool bio_flagged(struct bio
*bio
, unsigned int bit
)
234 return (bio
->bi_flags
& (1U << bit
)) != 0;
237 static inline void bio_set_flag(struct bio
*bio
, unsigned int bit
)
239 bio
->bi_flags
|= (1U << bit
);
242 static inline void bio_clear_flag(struct bio
*bio
, unsigned int bit
)
244 bio
->bi_flags
&= ~(1U << bit
);
247 static inline void bio_get_first_bvec(struct bio
*bio
, struct bio_vec
*bv
)
249 *bv
= bio_iovec(bio
);
252 static inline void bio_get_last_bvec(struct bio
*bio
, struct bio_vec
*bv
)
254 struct bvec_iter iter
= bio
->bi_iter
;
257 if (unlikely(!bio_multiple_segments(bio
))) {
258 *bv
= bio_iovec(bio
);
262 bio_advance_iter(bio
, &iter
, iter
.bi_size
);
264 if (!iter
.bi_bvec_done
)
265 idx
= iter
.bi_idx
- 1;
266 else /* in the middle of bvec */
269 *bv
= bio
->bi_io_vec
[idx
];
272 * iter.bi_bvec_done records actual length of the last bvec
273 * if this bio ends in the middle of one io vector
275 if (iter
.bi_bvec_done
)
276 bv
->bv_len
= iter
.bi_bvec_done
;
279 static inline struct bio_vec
*bio_first_bvec_all(struct bio
*bio
)
281 WARN_ON_ONCE(bio_flagged(bio
, BIO_CLONED
));
282 return bio
->bi_io_vec
;
285 static inline struct page
*bio_first_page_all(struct bio
*bio
)
287 return bio_first_bvec_all(bio
)->bv_page
;
290 static inline struct bio_vec
*bio_last_bvec_all(struct bio
*bio
)
292 WARN_ON_ONCE(bio_flagged(bio
, BIO_CLONED
));
293 return &bio
->bi_io_vec
[bio
->bi_vcnt
- 1];
297 BIP_BLOCK_INTEGRITY
= 1 << 0, /* block layer owns integrity data */
298 BIP_MAPPED_INTEGRITY
= 1 << 1, /* ref tag has been remapped */
299 BIP_CTRL_NOCHECK
= 1 << 2, /* disable HBA integrity checking */
300 BIP_DISK_NOCHECK
= 1 << 3, /* disable disk integrity checking */
301 BIP_IP_CHECKSUM
= 1 << 4, /* IP checksum */
305 * bio integrity payload
307 struct bio_integrity_payload
{
308 struct bio
*bip_bio
; /* parent bio */
310 struct bvec_iter bip_iter
;
312 unsigned short bip_slab
; /* slab the bip came from */
313 unsigned short bip_vcnt
; /* # of integrity bio_vecs */
314 unsigned short bip_max_vcnt
; /* integrity bio_vec slots */
315 unsigned short bip_flags
; /* control flags */
317 struct bvec_iter bio_iter
; /* for rewinding parent bio */
319 struct work_struct bip_work
; /* I/O completion */
321 struct bio_vec
*bip_vec
;
322 struct bio_vec bip_inline_vecs
[];/* embedded bvec array */
325 #if defined(CONFIG_BLK_DEV_INTEGRITY)
327 static inline struct bio_integrity_payload
*bio_integrity(struct bio
*bio
)
329 if (bio
->bi_opf
& REQ_INTEGRITY
)
330 return bio
->bi_integrity
;
335 static inline bool bio_integrity_flagged(struct bio
*bio
, enum bip_flags flag
)
337 struct bio_integrity_payload
*bip
= bio_integrity(bio
);
340 return bip
->bip_flags
& flag
;
345 static inline sector_t
bip_get_seed(struct bio_integrity_payload
*bip
)
347 return bip
->bip_iter
.bi_sector
;
350 static inline void bip_set_seed(struct bio_integrity_payload
*bip
,
353 bip
->bip_iter
.bi_sector
= seed
;
356 #endif /* CONFIG_BLK_DEV_INTEGRITY */
358 extern void bio_trim(struct bio
*bio
, int offset
, int size
);
359 extern struct bio
*bio_split(struct bio
*bio
, int sectors
,
360 gfp_t gfp
, struct bio_set
*bs
);
363 * bio_next_split - get next @sectors from a bio, splitting if necessary
365 * @sectors: number of sectors to split from the front of @bio
367 * @bs: bio set to allocate from
369 * Returns a bio representing the next @sectors of @bio - if the bio is smaller
370 * than @sectors, returns the original bio unchanged.
372 static inline struct bio
*bio_next_split(struct bio
*bio
, int sectors
,
373 gfp_t gfp
, struct bio_set
*bs
)
375 if (sectors
>= bio_sectors(bio
))
378 return bio_split(bio
, sectors
, gfp
, bs
);
382 BIOSET_NEED_BVECS
= BIT(0),
383 BIOSET_NEED_RESCUER
= BIT(1),
385 extern int bioset_init(struct bio_set
*, unsigned int, unsigned int, int flags
);
386 extern void bioset_exit(struct bio_set
*);
387 extern int biovec_init_pool(mempool_t
*pool
, int pool_entries
);
388 extern int bioset_init_from_src(struct bio_set
*bs
, struct bio_set
*src
);
390 extern struct bio
*bio_alloc_bioset(gfp_t
, unsigned int, struct bio_set
*);
391 extern void bio_put(struct bio
*);
393 extern void __bio_clone_fast(struct bio
*, struct bio
*);
394 extern struct bio
*bio_clone_fast(struct bio
*, gfp_t
, struct bio_set
*);
396 extern struct bio_set fs_bio_set
;
398 static inline struct bio
*bio_alloc(gfp_t gfp_mask
, unsigned int nr_iovecs
)
400 return bio_alloc_bioset(gfp_mask
, nr_iovecs
, &fs_bio_set
);
403 static inline struct bio
*bio_kmalloc(gfp_t gfp_mask
, unsigned int nr_iovecs
)
405 return bio_alloc_bioset(gfp_mask
, nr_iovecs
, NULL
);
408 extern blk_qc_t
submit_bio(struct bio
*);
410 extern void bio_endio(struct bio
*);
412 static inline void bio_io_error(struct bio
*bio
)
414 bio
->bi_status
= BLK_STS_IOERR
;
418 static inline void bio_wouldblock_error(struct bio
*bio
)
420 bio
->bi_status
= BLK_STS_AGAIN
;
424 struct request_queue
;
426 extern int submit_bio_wait(struct bio
*bio
);
427 extern void bio_advance(struct bio
*, unsigned);
429 extern void bio_init(struct bio
*bio
, struct bio_vec
*table
,
430 unsigned short max_vecs
);
431 extern void bio_uninit(struct bio
*);
432 extern void bio_reset(struct bio
*);
433 void bio_chain(struct bio
*, struct bio
*);
435 extern int bio_add_page(struct bio
*, struct page
*, unsigned int,unsigned int);
436 extern int bio_add_pc_page(struct request_queue
*, struct bio
*, struct page
*,
437 unsigned int, unsigned int);
438 bool __bio_try_merge_page(struct bio
*bio
, struct page
*page
,
439 unsigned int len
, unsigned int off
, bool *same_page
);
440 void __bio_add_page(struct bio
*bio
, struct page
*page
,
441 unsigned int len
, unsigned int off
);
442 int bio_iov_iter_get_pages(struct bio
*bio
, struct iov_iter
*iter
);
443 void bio_release_pages(struct bio
*bio
, bool mark_dirty
);
444 extern void bio_set_pages_dirty(struct bio
*bio
);
445 extern void bio_check_pages_dirty(struct bio
*bio
);
447 void generic_start_io_acct(struct request_queue
*q
, int op
,
448 unsigned long sectors
, struct hd_struct
*part
);
449 void generic_end_io_acct(struct request_queue
*q
, int op
,
450 struct hd_struct
*part
,
451 unsigned long start_time
);
453 extern void bio_copy_data_iter(struct bio
*dst
, struct bvec_iter
*dst_iter
,
454 struct bio
*src
, struct bvec_iter
*src_iter
);
455 extern void bio_copy_data(struct bio
*dst
, struct bio
*src
);
456 extern void bio_list_copy_data(struct bio
*dst
, struct bio
*src
);
457 extern void bio_free_pages(struct bio
*bio
);
458 void zero_fill_bio_iter(struct bio
*bio
, struct bvec_iter iter
);
459 void bio_truncate(struct bio
*bio
, unsigned new_size
);
460 void guard_bio_eod(struct bio
*bio
);
462 static inline void zero_fill_bio(struct bio
*bio
)
464 zero_fill_bio_iter(bio
, bio
->bi_iter
);
467 extern struct bio_vec
*bvec_alloc(gfp_t
, int, unsigned long *, mempool_t
*);
468 extern void bvec_free(mempool_t
*, struct bio_vec
*, unsigned int);
469 extern unsigned int bvec_nr_vecs(unsigned short idx
);
470 extern const char *bio_devname(struct bio
*bio
, char *buffer
);
472 #define bio_set_dev(bio, bdev) \
474 if ((bio)->bi_disk != (bdev)->bd_disk) \
475 bio_clear_flag(bio, BIO_THROTTLED);\
476 (bio)->bi_disk = (bdev)->bd_disk; \
477 (bio)->bi_partno = (bdev)->bd_partno; \
478 bio_associate_blkg(bio); \
481 #define bio_copy_dev(dst, src) \
483 (dst)->bi_disk = (src)->bi_disk; \
484 (dst)->bi_partno = (src)->bi_partno; \
485 bio_clone_blkg_association(dst, src); \
488 #define bio_dev(bio) \
489 disk_devt((bio)->bi_disk)
491 #if defined(CONFIG_MEMCG) && defined(CONFIG_BLK_CGROUP)
492 void bio_associate_blkg_from_page(struct bio
*bio
, struct page
*page
);
494 static inline void bio_associate_blkg_from_page(struct bio
*bio
,
495 struct page
*page
) { }
498 #ifdef CONFIG_BLK_CGROUP
499 void bio_disassociate_blkg(struct bio
*bio
);
500 void bio_associate_blkg(struct bio
*bio
);
501 void bio_associate_blkg_from_css(struct bio
*bio
,
502 struct cgroup_subsys_state
*css
);
503 void bio_clone_blkg_association(struct bio
*dst
, struct bio
*src
);
504 #else /* CONFIG_BLK_CGROUP */
505 static inline void bio_disassociate_blkg(struct bio
*bio
) { }
506 static inline void bio_associate_blkg(struct bio
*bio
) { }
507 static inline void bio_associate_blkg_from_css(struct bio
*bio
,
508 struct cgroup_subsys_state
*css
)
510 static inline void bio_clone_blkg_association(struct bio
*dst
,
512 #endif /* CONFIG_BLK_CGROUP */
514 #ifdef CONFIG_HIGHMEM
516 * remember never ever reenable interrupts between a bvec_kmap_irq and
519 static inline char *bvec_kmap_irq(struct bio_vec
*bvec
, unsigned long *flags
)
524 * might not be a highmem page, but the preempt/irq count
525 * balancing is a lot nicer this way
527 local_irq_save(*flags
);
528 addr
= (unsigned long) kmap_atomic(bvec
->bv_page
);
530 BUG_ON(addr
& ~PAGE_MASK
);
532 return (char *) addr
+ bvec
->bv_offset
;
535 static inline void bvec_kunmap_irq(char *buffer
, unsigned long *flags
)
537 unsigned long ptr
= (unsigned long) buffer
& PAGE_MASK
;
539 kunmap_atomic((void *) ptr
);
540 local_irq_restore(*flags
);
544 static inline char *bvec_kmap_irq(struct bio_vec
*bvec
, unsigned long *flags
)
546 return page_address(bvec
->bv_page
) + bvec
->bv_offset
;
549 static inline void bvec_kunmap_irq(char *buffer
, unsigned long *flags
)
556 * BIO list management for use by remapping drivers (e.g. DM or MD) and loop.
558 * A bio_list anchors a singly-linked list of bios chained through the bi_next
559 * member of the bio. The bio_list also caches the last list member to allow
560 * fast access to the tail.
567 static inline int bio_list_empty(const struct bio_list
*bl
)
569 return bl
->head
== NULL
;
572 static inline void bio_list_init(struct bio_list
*bl
)
574 bl
->head
= bl
->tail
= NULL
;
577 #define BIO_EMPTY_LIST { NULL, NULL }
579 #define bio_list_for_each(bio, bl) \
580 for (bio = (bl)->head; bio; bio = bio->bi_next)
582 static inline unsigned bio_list_size(const struct bio_list
*bl
)
587 bio_list_for_each(bio
, bl
)
593 static inline void bio_list_add(struct bio_list
*bl
, struct bio
*bio
)
598 bl
->tail
->bi_next
= bio
;
605 static inline void bio_list_add_head(struct bio_list
*bl
, struct bio
*bio
)
607 bio
->bi_next
= bl
->head
;
615 static inline void bio_list_merge(struct bio_list
*bl
, struct bio_list
*bl2
)
621 bl
->tail
->bi_next
= bl2
->head
;
623 bl
->head
= bl2
->head
;
625 bl
->tail
= bl2
->tail
;
628 static inline void bio_list_merge_head(struct bio_list
*bl
,
629 struct bio_list
*bl2
)
635 bl2
->tail
->bi_next
= bl
->head
;
637 bl
->tail
= bl2
->tail
;
639 bl
->head
= bl2
->head
;
642 static inline struct bio
*bio_list_peek(struct bio_list
*bl
)
647 static inline struct bio
*bio_list_pop(struct bio_list
*bl
)
649 struct bio
*bio
= bl
->head
;
652 bl
->head
= bl
->head
->bi_next
;
662 static inline struct bio
*bio_list_get(struct bio_list
*bl
)
664 struct bio
*bio
= bl
->head
;
666 bl
->head
= bl
->tail
= NULL
;
672 * Increment chain count for the bio. Make sure the CHAIN flag update
673 * is visible before the raised count.
675 static inline void bio_inc_remaining(struct bio
*bio
)
677 bio_set_flag(bio
, BIO_CHAIN
);
678 smp_mb__before_atomic();
679 atomic_inc(&bio
->__bi_remaining
);
683 * bio_set is used to allow other portions of the IO system to
684 * allocate their own private memory pools for bio and iovec structures.
685 * These memory pools in turn all allocate from the bio_slab
686 * and the bvec_slabs[].
688 #define BIO_POOL_SIZE 2
691 struct kmem_cache
*bio_slab
;
692 unsigned int front_pad
;
696 #if defined(CONFIG_BLK_DEV_INTEGRITY)
697 mempool_t bio_integrity_pool
;
698 mempool_t bvec_integrity_pool
;
702 * Deadlock avoidance for stacking block drivers: see comments in
703 * bio_alloc_bioset() for details
705 spinlock_t rescue_lock
;
706 struct bio_list rescue_list
;
707 struct work_struct rescue_work
;
708 struct workqueue_struct
*rescue_workqueue
;
714 struct kmem_cache
*slab
;
717 static inline bool bioset_initialized(struct bio_set
*bs
)
719 return bs
->bio_slab
!= NULL
;
723 * a small number of entries is fine, not going to be performance critical.
724 * basically we just need to survive
726 #define BIO_SPLIT_ENTRIES 2
728 #if defined(CONFIG_BLK_DEV_INTEGRITY)
730 #define bip_for_each_vec(bvl, bip, iter) \
731 for_each_bvec(bvl, (bip)->bip_vec, iter, (bip)->bip_iter)
733 #define bio_for_each_integrity_vec(_bvl, _bio, _iter) \
735 bip_for_each_vec(_bvl, _bio->bi_integrity, _iter)
737 extern struct bio_integrity_payload
*bio_integrity_alloc(struct bio
*, gfp_t
, unsigned int);
738 extern int bio_integrity_add_page(struct bio
*, struct page
*, unsigned int, unsigned int);
739 extern bool bio_integrity_prep(struct bio
*);
740 extern void bio_integrity_advance(struct bio
*, unsigned int);
741 extern void bio_integrity_trim(struct bio
*);
742 extern int bio_integrity_clone(struct bio
*, struct bio
*, gfp_t
);
743 extern int bioset_integrity_create(struct bio_set
*, int);
744 extern void bioset_integrity_free(struct bio_set
*);
745 extern void bio_integrity_init(void);
747 #else /* CONFIG_BLK_DEV_INTEGRITY */
749 static inline void *bio_integrity(struct bio
*bio
)
754 static inline int bioset_integrity_create(struct bio_set
*bs
, int pool_size
)
759 static inline void bioset_integrity_free (struct bio_set
*bs
)
764 static inline bool bio_integrity_prep(struct bio
*bio
)
769 static inline int bio_integrity_clone(struct bio
*bio
, struct bio
*bio_src
,
775 static inline void bio_integrity_advance(struct bio
*bio
,
776 unsigned int bytes_done
)
781 static inline void bio_integrity_trim(struct bio
*bio
)
786 static inline void bio_integrity_init(void)
791 static inline bool bio_integrity_flagged(struct bio
*bio
, enum bip_flags flag
)
796 static inline void *bio_integrity_alloc(struct bio
* bio
, gfp_t gfp
,
799 return ERR_PTR(-EINVAL
);
802 static inline int bio_integrity_add_page(struct bio
*bio
, struct page
*page
,
803 unsigned int len
, unsigned int offset
)
808 #endif /* CONFIG_BLK_DEV_INTEGRITY */
811 * Mark a bio as polled. Note that for async polled IO, the caller must
812 * expect -EWOULDBLOCK if we cannot allocate a request (or other resources).
813 * We cannot block waiting for requests on polled IO, as those completions
814 * must be found by the caller. This is different than IRQ driven IO, where
815 * it's safe to wait for IO to complete.
817 static inline void bio_set_polled(struct bio
*bio
, struct kiocb
*kiocb
)
819 bio
->bi_opf
|= REQ_HIPRI
;
820 if (!is_sync_kiocb(kiocb
))
821 bio
->bi_opf
|= REQ_NOWAIT
;
824 #endif /* CONFIG_BLOCK */
825 #endif /* __LINUX_BIO_H */