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
44 #define BIO_MAX_SIZE (BIO_MAX_PAGES << PAGE_CACHE_SHIFT)
45 #define BIO_MAX_SECTORS (BIO_MAX_SIZE >> 9)
48 * upper 16 bits of bi_rw define the io priority of this bio
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))
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); \
61 * various member access, note that bio_data should of course not be used
62 * on highmem page vectors
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)
71 static inline unsigned int bio_cur_bytes(struct bio
*bio
)
74 return bio_iovec(bio
)->bv_len
;
75 else /* dataless requests such as discard */
79 static inline void *bio_data(struct bio
*bio
)
82 return page_address(bio_page(bio
)) + bio_offset(bio
);
87 static inline int bio_has_allocated_vec(struct bio
*bio
)
89 return bio
->bi_io_vec
&& bio
->bi_io_vec
!= bio
->bi_inline_vecs
;
95 #define bio_to_phys(bio) (page_to_phys(bio_page((bio))) + (unsigned long) bio_offset((bio)))
96 #define bvec_to_phys(bv) (page_to_phys((bv)->bv_page) + (unsigned long) (bv)->bv_offset)
99 * queues that have highmem support enabled may still need to revert to
100 * PIO transfers occasionally and thus map high pages temporarily. For
101 * permanent PIO fall back, user is probably better off disabling highmem
102 * I/O completely on that queue (see ide-dma for example)
104 #define __bio_kmap_atomic(bio, idx, kmtype) \
105 (kmap_atomic(bio_iovec_idx((bio), (idx))->bv_page) + \
106 bio_iovec_idx((bio), (idx))->bv_offset)
108 #define __bio_kunmap_atomic(addr, kmtype) kunmap_atomic(addr)
114 #define __BVEC_END(bio) bio_iovec_idx((bio), (bio)->bi_vcnt - 1)
115 #define __BVEC_START(bio) bio_iovec_idx((bio), (bio)->bi_idx)
117 /* Default implementation of BIOVEC_PHYS_MERGEABLE */
118 #define __BIOVEC_PHYS_MERGEABLE(vec1, vec2) \
119 ((bvec_to_phys((vec1)) + (vec1)->bv_len) == bvec_to_phys((vec2)))
122 * allow arch override, for eg virtualized architectures (put in asm/io.h)
124 #ifndef BIOVEC_PHYS_MERGEABLE
125 #define BIOVEC_PHYS_MERGEABLE(vec1, vec2) \
126 __BIOVEC_PHYS_MERGEABLE(vec1, vec2)
129 #define __BIO_SEG_BOUNDARY(addr1, addr2, mask) \
130 (((addr1) | (mask)) == (((addr2) - 1) | (mask)))
131 #define BIOVEC_SEG_BOUNDARY(q, b1, b2) \
132 __BIO_SEG_BOUNDARY(bvec_to_phys((b1)), bvec_to_phys((b2)) + (b2)->bv_len, queue_segment_boundary((q)))
133 #define BIO_SEG_BOUNDARY(q, b1, b2) \
134 BIOVEC_SEG_BOUNDARY((q), __BVEC_END((b1)), __BVEC_START((b2)))
136 #define bio_io_error(bio) bio_endio((bio), -EIO)
139 * drivers should not use the __ version unless they _really_ want to
140 * run through the entire bio and not just pending pieces
142 #define __bio_for_each_segment(bvl, bio, i, start_idx) \
143 for (bvl = bio_iovec_idx((bio), (start_idx)), i = (start_idx); \
144 i < (bio)->bi_vcnt; \
147 #define bio_for_each_segment(bvl, bio, i) \
148 __bio_for_each_segment(bvl, bio, i, (bio)->bi_idx)
151 * get a reference to a bio, so it won't disappear. the intended use is
155 * submit_bio(rw, bio);
156 * if (bio->bi_flags ...)
160 * without the bio_get(), it could potentially complete I/O before submit_bio
161 * returns. and then bio would be freed memory when if (bio->bi_flags ...)
164 #define bio_get(bio) atomic_inc(&(bio)->bi_cnt)
166 #if defined(CONFIG_BLK_DEV_INTEGRITY)
168 * bio integrity payload
170 struct bio_integrity_payload
{
171 struct bio
*bip_bio
; /* parent bio */
173 sector_t bip_sector
; /* virtual start sector */
175 void *bip_buf
; /* generated integrity data */
176 bio_end_io_t
*bip_end_io
; /* saved I/O completion fn */
178 unsigned int bip_size
;
180 unsigned short bip_slab
; /* slab the bip came from */
181 unsigned short bip_vcnt
; /* # of integrity bio_vecs */
182 unsigned short bip_idx
; /* current bip_vec index */
184 struct work_struct bip_work
; /* I/O completion */
185 struct bio_vec bip_vec
[0]; /* embedded bvec array */
187 #endif /* CONFIG_BLK_DEV_INTEGRITY */
190 * A bio_pair is used when we need to split a bio.
191 * This can only happen for a bio that refers to just one
192 * page of data, and in the unusual situation when the
193 * page crosses a chunk/device boundary
195 * The address of the master bio is stored in bio1.bi_private
196 * The address of the pool the pair was allocated from is stored
200 struct bio bio1
, bio2
;
201 struct bio_vec bv1
, bv2
;
202 #if defined(CONFIG_BLK_DEV_INTEGRITY)
203 struct bio_integrity_payload bip1
, bip2
;
204 struct bio_vec iv1
, iv2
;
209 extern struct bio_pair
*bio_split(struct bio
*bi
, int first_sectors
);
210 extern void bio_pair_release(struct bio_pair
*dbio
);
212 extern struct bio_set
*bioset_create(unsigned int, unsigned int);
213 extern void bioset_free(struct bio_set
*);
215 extern struct bio
*bio_alloc_bioset(gfp_t
, int, struct bio_set
*);
216 extern void bio_put(struct bio
*);
218 extern void __bio_clone(struct bio
*, struct bio
*);
219 extern struct bio
*bio_clone_bioset(struct bio
*, gfp_t
, struct bio_set
*bs
);
221 extern struct bio_set
*fs_bio_set
;
223 static inline struct bio
*bio_alloc(gfp_t gfp_mask
, unsigned int nr_iovecs
)
225 return bio_alloc_bioset(gfp_mask
, nr_iovecs
, fs_bio_set
);
228 static inline struct bio
*bio_clone(struct bio
*bio
, gfp_t gfp_mask
)
230 return bio_clone_bioset(bio
, gfp_mask
, fs_bio_set
);
233 static inline struct bio
*bio_kmalloc(gfp_t gfp_mask
, unsigned int nr_iovecs
)
235 return bio_alloc_bioset(gfp_mask
, nr_iovecs
, NULL
);
238 static inline struct bio
*bio_clone_kmalloc(struct bio
*bio
, gfp_t gfp_mask
)
240 return bio_clone_bioset(bio
, gfp_mask
, NULL
);
244 extern void bio_endio(struct bio
*, int);
245 struct request_queue
;
246 extern int bio_phys_segments(struct request_queue
*, struct bio
*);
248 extern void bio_init(struct bio
*);
249 extern void bio_reset(struct bio
*);
251 extern int bio_add_page(struct bio
*, struct page
*, unsigned int,unsigned int);
252 extern int bio_add_pc_page(struct request_queue
*, struct bio
*, struct page
*,
253 unsigned int, unsigned int);
254 extern int bio_get_nr_vecs(struct block_device
*);
255 extern sector_t
bio_sector_offset(struct bio
*, unsigned short, unsigned int);
256 extern struct bio
*bio_map_user(struct request_queue
*, struct block_device
*,
257 unsigned long, unsigned int, int, gfp_t
);
260 extern struct bio
*bio_map_user_iov(struct request_queue
*,
261 struct block_device
*,
262 struct sg_iovec
*, int, int, gfp_t
);
263 extern void bio_unmap_user(struct bio
*);
264 extern struct bio
*bio_map_kern(struct request_queue
*, void *, unsigned int,
266 extern struct bio
*bio_copy_kern(struct request_queue
*, void *, unsigned int,
268 extern void bio_set_pages_dirty(struct bio
*bio
);
269 extern void bio_check_pages_dirty(struct bio
*bio
);
271 #ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
272 # error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform"
274 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
275 extern void bio_flush_dcache_pages(struct bio
*bi
);
277 static inline void bio_flush_dcache_pages(struct bio
*bi
)
282 extern struct bio
*bio_copy_user(struct request_queue
*, struct rq_map_data
*,
283 unsigned long, unsigned int, int, gfp_t
);
284 extern struct bio
*bio_copy_user_iov(struct request_queue
*,
285 struct rq_map_data
*, struct sg_iovec
*,
287 extern int bio_uncopy_user(struct bio
*);
288 void zero_fill_bio(struct bio
*bio
);
289 extern struct bio_vec
*bvec_alloc_bs(gfp_t
, int, unsigned long *, struct bio_set
*);
290 extern void bvec_free_bs(struct bio_set
*, struct bio_vec
*, unsigned int);
291 extern unsigned int bvec_nr_vecs(unsigned short idx
);
293 #ifdef CONFIG_BLK_CGROUP
294 int bio_associate_current(struct bio
*bio
);
295 void bio_disassociate_task(struct bio
*bio
);
296 #else /* CONFIG_BLK_CGROUP */
297 static inline int bio_associate_current(struct bio
*bio
) { return -ENOENT
; }
298 static inline void bio_disassociate_task(struct bio
*bio
) { }
299 #endif /* CONFIG_BLK_CGROUP */
302 * bio_set is used to allow other portions of the IO system to
303 * allocate their own private memory pools for bio and iovec structures.
304 * These memory pools in turn all allocate from the bio_slab
305 * and the bvec_slabs[].
307 #define BIO_POOL_SIZE 2
308 #define BIOVEC_NR_POOLS 6
309 #define BIOVEC_MAX_IDX (BIOVEC_NR_POOLS - 1)
312 struct kmem_cache
*bio_slab
;
313 unsigned int front_pad
;
316 #if defined(CONFIG_BLK_DEV_INTEGRITY)
317 mempool_t
*bio_integrity_pool
;
319 mempool_t
*bvec_pool
;
325 struct kmem_cache
*slab
;
329 * a small number of entries is fine, not going to be performance critical.
330 * basically we just need to survive
332 #define BIO_SPLIT_ENTRIES 2
334 #ifdef CONFIG_HIGHMEM
336 * remember never ever reenable interrupts between a bvec_kmap_irq and
339 static inline char *bvec_kmap_irq(struct bio_vec
*bvec
, unsigned long *flags
)
344 * might not be a highmem page, but the preempt/irq count
345 * balancing is a lot nicer this way
347 local_irq_save(*flags
);
348 addr
= (unsigned long) kmap_atomic(bvec
->bv_page
);
350 BUG_ON(addr
& ~PAGE_MASK
);
352 return (char *) addr
+ bvec
->bv_offset
;
355 static inline void bvec_kunmap_irq(char *buffer
, unsigned long *flags
)
357 unsigned long ptr
= (unsigned long) buffer
& PAGE_MASK
;
359 kunmap_atomic((void *) ptr
);
360 local_irq_restore(*flags
);
364 static inline char *bvec_kmap_irq(struct bio_vec
*bvec
, unsigned long *flags
)
366 return page_address(bvec
->bv_page
) + bvec
->bv_offset
;
369 static inline void bvec_kunmap_irq(char *buffer
, unsigned long *flags
)
375 static inline char *__bio_kmap_irq(struct bio
*bio
, unsigned short idx
,
376 unsigned long *flags
)
378 return bvec_kmap_irq(bio_iovec_idx(bio
, idx
), flags
);
380 #define __bio_kunmap_irq(buf, flags) bvec_kunmap_irq(buf, flags)
382 #define bio_kmap_irq(bio, flags) \
383 __bio_kmap_irq((bio), (bio)->bi_idx, (flags))
384 #define bio_kunmap_irq(buf,flags) __bio_kunmap_irq(buf, flags)
387 * Check whether this bio carries any data or not. A NULL bio is allowed.
389 static inline bool bio_has_data(struct bio
*bio
)
391 if (bio
&& bio
->bi_vcnt
)
397 static inline bool bio_is_rw(struct bio
*bio
)
399 if (!bio_has_data(bio
))
402 if (bio
->bi_rw
& REQ_WRITE_SAME
)
408 static inline bool bio_mergeable(struct bio
*bio
)
410 if (bio
->bi_rw
& REQ_NOMERGE_FLAGS
)
417 * BIO list management for use by remapping drivers (e.g. DM or MD) and loop.
419 * A bio_list anchors a singly-linked list of bios chained through the bi_next
420 * member of the bio. The bio_list also caches the last list member to allow
421 * fast access to the tail.
428 static inline int bio_list_empty(const struct bio_list
*bl
)
430 return bl
->head
== NULL
;
433 static inline void bio_list_init(struct bio_list
*bl
)
435 bl
->head
= bl
->tail
= NULL
;
438 #define bio_list_for_each(bio, bl) \
439 for (bio = (bl)->head; bio; bio = bio->bi_next)
441 static inline unsigned bio_list_size(const struct bio_list
*bl
)
446 bio_list_for_each(bio
, bl
)
452 static inline void bio_list_add(struct bio_list
*bl
, struct bio
*bio
)
457 bl
->tail
->bi_next
= bio
;
464 static inline void bio_list_add_head(struct bio_list
*bl
, struct bio
*bio
)
466 bio
->bi_next
= bl
->head
;
474 static inline void bio_list_merge(struct bio_list
*bl
, struct bio_list
*bl2
)
480 bl
->tail
->bi_next
= bl2
->head
;
482 bl
->head
= bl2
->head
;
484 bl
->tail
= bl2
->tail
;
487 static inline void bio_list_merge_head(struct bio_list
*bl
,
488 struct bio_list
*bl2
)
494 bl2
->tail
->bi_next
= bl
->head
;
496 bl
->tail
= bl2
->tail
;
498 bl
->head
= bl2
->head
;
501 static inline struct bio
*bio_list_peek(struct bio_list
*bl
)
506 static inline struct bio
*bio_list_pop(struct bio_list
*bl
)
508 struct bio
*bio
= bl
->head
;
511 bl
->head
= bl
->head
->bi_next
;
521 static inline struct bio
*bio_list_get(struct bio_list
*bl
)
523 struct bio
*bio
= bl
->head
;
525 bl
->head
= bl
->tail
= NULL
;
530 #if defined(CONFIG_BLK_DEV_INTEGRITY)
532 #define bip_vec_idx(bip, idx) (&(bip->bip_vec[(idx)]))
533 #define bip_vec(bip) bip_vec_idx(bip, 0)
535 #define __bip_for_each_vec(bvl, bip, i, start_idx) \
536 for (bvl = bip_vec_idx((bip), (start_idx)), i = (start_idx); \
537 i < (bip)->bip_vcnt; \
540 #define bip_for_each_vec(bvl, bip, i) \
541 __bip_for_each_vec(bvl, bip, i, (bip)->bip_idx)
543 #define bio_for_each_integrity_vec(_bvl, _bio, _iter) \
545 bip_for_each_vec(_bvl, _bio->bi_integrity, _iter)
547 #define bio_integrity(bio) (bio->bi_integrity != NULL)
549 extern struct bio_integrity_payload
*bio_integrity_alloc(struct bio
*, gfp_t
, unsigned int);
550 extern void bio_integrity_free(struct bio
*);
551 extern int bio_integrity_add_page(struct bio
*, struct page
*, unsigned int, unsigned int);
552 extern int bio_integrity_enabled(struct bio
*bio
);
553 extern int bio_integrity_set_tag(struct bio
*, void *, unsigned int);
554 extern int bio_integrity_get_tag(struct bio
*, void *, unsigned int);
555 extern int bio_integrity_prep(struct bio
*);
556 extern void bio_integrity_endio(struct bio
*, int);
557 extern void bio_integrity_advance(struct bio
*, unsigned int);
558 extern void bio_integrity_trim(struct bio
*, unsigned int, unsigned int);
559 extern void bio_integrity_split(struct bio
*, struct bio_pair
*, int);
560 extern int bio_integrity_clone(struct bio
*, struct bio
*, gfp_t
);
561 extern int bioset_integrity_create(struct bio_set
*, int);
562 extern void bioset_integrity_free(struct bio_set
*);
563 extern void bio_integrity_init(void);
565 #else /* CONFIG_BLK_DEV_INTEGRITY */
567 static inline int bio_integrity(struct bio
*bio
)
572 static inline int bio_integrity_enabled(struct bio
*bio
)
577 static inline int bioset_integrity_create(struct bio_set
*bs
, int pool_size
)
582 static inline void bioset_integrity_free (struct bio_set
*bs
)
587 static inline int bio_integrity_prep(struct bio
*bio
)
592 static inline void bio_integrity_free(struct bio
*bio
)
597 static inline int bio_integrity_clone(struct bio
*bio
, struct bio
*bio_src
,
603 static inline void bio_integrity_split(struct bio
*bio
, struct bio_pair
*bp
,
609 static inline void bio_integrity_advance(struct bio
*bio
,
610 unsigned int bytes_done
)
615 static inline void bio_integrity_trim(struct bio
*bio
, unsigned int offset
,
616 unsigned int sectors
)
621 static inline void bio_integrity_init(void)
626 #endif /* CONFIG_BLK_DEV_INTEGRITY */
628 #endif /* CONFIG_BLOCK */
629 #endif /* __LINUX_BIO_H */