blob: 5a4d39b4686be4fb1f78c06442f29d4d955297d7 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
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
Tejun Heo7cc01582010-08-03 13:14:58 +020012 *
Linus Torvalds1da177e2005-04-16 15:20:36 -070013 * 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>
Jens Axboe22e2c502005-06-27 10:55:12 +020025#include <linux/ioprio.h>
Paul Gortmaker187f1882011-11-23 20:12:59 -050026#include <linux/bug.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070027
David Howells02a5e0a2007-08-11 22:34:32 +020028#ifdef CONFIG_BLOCK
29
Linus Torvalds1da177e2005-04-16 15:20:36 -070030#include <asm/io.h>
31
Tejun Heo7cc01582010-08-03 13:14:58 +020032/* struct bio, bio_vec and BIO_* flags are defined in blk_types.h */
33#include <linux/blk_types.h>
34
Linus Torvalds1da177e2005-04-16 15:20:36 -070035#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
Alexey Dobriyand84a8472006-06-25 05:49:32 -070043#define BIO_MAX_PAGES 256
Linus Torvalds1da177e2005-04-16 15:20:36 -070044#define BIO_MAX_SIZE (BIO_MAX_PAGES << PAGE_CACHE_SHIFT)
45#define BIO_MAX_SECTORS (BIO_MAX_SIZE >> 9)
46
47/*
Jens Axboe22e2c502005-06-27 10:55:12 +020048 * 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/*
Linus Torvalds1da177e2005-04-16 15:20:36 -070061 * various member access, note that bio_data should of course not be used
62 * on highmem page vectors
63 */
Kent Overstreet4550dd62013-08-07 14:26:21 -070064#define __bvec_iter_bvec(bvec, iter) (&(bvec)[(iter).bi_idx])
Kent Overstreeta4ad39b12013-08-07 14:24:32 -070065
Kent Overstreet4550dd62013-08-07 14:26:21 -070066#define bvec_iter_page(bvec, iter) \
67 (__bvec_iter_bvec((bvec), (iter))->bv_page)
68
69#define bvec_iter_len(bvec, iter) \
70 min((iter).bi_size, \
71 __bvec_iter_bvec((bvec), (iter))->bv_len - (iter).bi_bvec_done)
72
73#define bvec_iter_offset(bvec, iter) \
74 (__bvec_iter_bvec((bvec), (iter))->bv_offset + (iter).bi_bvec_done)
75
76#define bvec_iter_bvec(bvec, iter) \
77((struct bio_vec) { \
78 .bv_page = bvec_iter_page((bvec), (iter)), \
79 .bv_len = bvec_iter_len((bvec), (iter)), \
80 .bv_offset = bvec_iter_offset((bvec), (iter)), \
81})
82
83#define bio_iter_iovec(bio, iter) \
84 bvec_iter_bvec((bio)->bi_io_vec, (iter))
85
86#define bio_iter_page(bio, iter) \
87 bvec_iter_page((bio)->bi_io_vec, (iter))
88#define bio_iter_len(bio, iter) \
89 bvec_iter_len((bio)->bi_io_vec, (iter))
90#define bio_iter_offset(bio, iter) \
91 bvec_iter_offset((bio)->bi_io_vec, (iter))
92
93#define bio_page(bio) bio_iter_page((bio), (bio)->bi_iter)
94#define bio_offset(bio) bio_iter_offset((bio), (bio)->bi_iter)
95#define bio_iovec(bio) bio_iter_iovec((bio), (bio)->bi_iter)
Kent Overstreet79886132013-11-23 17:19:00 -080096
Kent Overstreet458b76e2013-09-24 16:26:05 -070097#define bio_multiple_segments(bio) \
98 ((bio)->bi_iter.bi_size != bio_iovec(bio).bv_len)
Kent Overstreet4f024f32013-10-11 15:44:27 -070099#define bio_sectors(bio) ((bio)->bi_iter.bi_size >> 9)
100#define bio_end_sector(bio) ((bio)->bi_iter.bi_sector + bio_sectors((bio)))
Jens Axboebf2de6f2007-09-27 13:01:25 +0200101
Kent Overstreet458b76e2013-09-24 16:26:05 -0700102/*
103 * Check whether this bio carries any data or not. A NULL bio is allowed.
104 */
105static inline bool bio_has_data(struct bio *bio)
106{
107 if (bio &&
108 bio->bi_iter.bi_size &&
109 !(bio->bi_rw & REQ_DISCARD))
110 return true;
111
112 return false;
113}
114
115static inline bool bio_is_rw(struct bio *bio)
116{
117 if (!bio_has_data(bio))
118 return false;
119
120 if (bio->bi_rw & BIO_NO_ADVANCE_ITER_MASK)
121 return false;
122
123 return true;
124}
125
126static inline bool bio_mergeable(struct bio *bio)
127{
128 if (bio->bi_rw & REQ_NOMERGE_FLAGS)
129 return false;
130
131 return true;
132}
133
Tejun Heo2e46e8b2009-05-07 22:24:41 +0900134static inline unsigned int bio_cur_bytes(struct bio *bio)
Jens Axboebf2de6f2007-09-27 13:01:25 +0200135{
Kent Overstreet458b76e2013-09-24 16:26:05 -0700136 if (bio_has_data(bio))
Kent Overstreeta4ad39b12013-08-07 14:24:32 -0700137 return bio_iovec(bio).bv_len;
David Woodhousefb2dce82008-08-05 18:01:53 +0100138 else /* dataless requests such as discard */
Kent Overstreet4f024f32013-10-11 15:44:27 -0700139 return bio->bi_iter.bi_size;
Jens Axboebf2de6f2007-09-27 13:01:25 +0200140}
141
142static inline void *bio_data(struct bio *bio)
143{
Kent Overstreet458b76e2013-09-24 16:26:05 -0700144 if (bio_has_data(bio))
Jens Axboebf2de6f2007-09-27 13:01:25 +0200145 return page_address(bio_page(bio)) + bio_offset(bio);
146
147 return NULL;
148}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700149
150/*
151 * will die
152 */
153#define bio_to_phys(bio) (page_to_phys(bio_page((bio))) + (unsigned long) bio_offset((bio)))
154#define bvec_to_phys(bv) (page_to_phys((bv)->bv_page) + (unsigned long) (bv)->bv_offset)
155
156/*
157 * queues that have highmem support enabled may still need to revert to
158 * PIO transfers occasionally and thus map high pages temporarily. For
159 * permanent PIO fall back, user is probably better off disabling highmem
160 * I/O completely on that queue (see ide-dma for example)
161 */
Kent Overstreetf619d252013-08-07 14:30:33 -0700162#define __bio_kmap_atomic(bio, iter) \
163 (kmap_atomic(bio_iter_iovec((bio), (iter)).bv_page) + \
164 bio_iter_iovec((bio), (iter)).bv_offset)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700165
Kent Overstreetf619d252013-08-07 14:30:33 -0700166#define __bio_kunmap_atomic(addr) kunmap_atomic(addr)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700167
168/*
169 * merge helpers etc
170 */
171
Jeremy Fitzhardingef92131c2008-10-29 14:10:51 +0100172/* Default implementation of BIOVEC_PHYS_MERGEABLE */
173#define __BIOVEC_PHYS_MERGEABLE(vec1, vec2) \
174 ((bvec_to_phys((vec1)) + (vec1)->bv_len) == bvec_to_phys((vec2)))
175
Linus Torvalds1da177e2005-04-16 15:20:36 -0700176/*
177 * allow arch override, for eg virtualized architectures (put in asm/io.h)
178 */
179#ifndef BIOVEC_PHYS_MERGEABLE
180#define BIOVEC_PHYS_MERGEABLE(vec1, vec2) \
Jeremy Fitzhardingef92131c2008-10-29 14:10:51 +0100181 __BIOVEC_PHYS_MERGEABLE(vec1, vec2)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700182#endif
183
Linus Torvalds1da177e2005-04-16 15:20:36 -0700184#define __BIO_SEG_BOUNDARY(addr1, addr2, mask) \
185 (((addr1) | (mask)) == (((addr2) - 1) | (mask)))
186#define BIOVEC_SEG_BOUNDARY(q, b1, b2) \
Martin K. Petersenae03bf62009-05-22 17:17:50 -0400187 __BIO_SEG_BOUNDARY(bvec_to_phys((b1)), bvec_to_phys((b2)) + (b2)->bv_len, queue_segment_boundary((q)))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700188
NeilBrown6712ecf2007-09-27 12:47:43 +0200189#define bio_io_error(bio) bio_endio((bio), -EIO)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700190
191/*
Kent Overstreetd74c6d52013-02-06 12:23:11 -0800192 * drivers should _never_ use the all version - the bio may have been split
193 * before it got to the driver and the driver won't own all of it
194 */
195#define bio_for_each_segment_all(bvl, bio, i) \
Kent Overstreetf619d252013-08-07 14:30:33 -0700196 for (i = 0, bvl = (bio)->bi_io_vec; i < (bio)->bi_vcnt; i++, bvl++)
Kent Overstreetd74c6d52013-02-06 12:23:11 -0800197
Kent Overstreet4550dd62013-08-07 14:26:21 -0700198static inline void bvec_iter_advance(struct bio_vec *bv, struct bvec_iter *iter,
199 unsigned bytes)
200{
201 WARN_ONCE(bytes > iter->bi_size,
202 "Attempted to advance past end of bvec iter\n");
203
204 while (bytes) {
205 unsigned len = min(bytes, bvec_iter_len(bv, *iter));
206
207 bytes -= len;
208 iter->bi_size -= len;
209 iter->bi_bvec_done += len;
210
211 if (iter->bi_bvec_done == __bvec_iter_bvec(bv, *iter)->bv_len) {
212 iter->bi_bvec_done = 0;
213 iter->bi_idx++;
214 }
215 }
216}
217
218#define for_each_bvec(bvl, bio_vec, iter, start) \
219 for ((iter) = start; \
220 (bvl) = bvec_iter_bvec((bio_vec), (iter)), \
221 (iter).bi_size; \
222 bvec_iter_advance((bio_vec), &(iter), (bvl).bv_len))
223
224
225static inline void bio_advance_iter(struct bio *bio, struct bvec_iter *iter,
226 unsigned bytes)
227{
228 iter->bi_sector += bytes >> 9;
229
230 if (bio->bi_rw & BIO_NO_ADVANCE_ITER_MASK)
231 iter->bi_size -= bytes;
232 else
233 bvec_iter_advance(bio->bi_io_vec, iter, bytes);
234}
235
Kent Overstreet79886132013-11-23 17:19:00 -0800236#define __bio_for_each_segment(bvl, bio, iter, start) \
237 for (iter = (start); \
Kent Overstreet4550dd62013-08-07 14:26:21 -0700238 (iter).bi_size && \
239 ((bvl = bio_iter_iovec((bio), (iter))), 1); \
240 bio_advance_iter((bio), &(iter), (bvl).bv_len))
Kent Overstreet79886132013-11-23 17:19:00 -0800241
242#define bio_for_each_segment(bvl, bio, iter) \
243 __bio_for_each_segment(bvl, bio, iter, (bio)->bi_iter)
244
Kent Overstreet4550dd62013-08-07 14:26:21 -0700245#define bio_iter_last(bvec, iter) ((iter).bi_size == (bvec).bv_len)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700246
Kent Overstreet458b76e2013-09-24 16:26:05 -0700247static inline unsigned bio_segments(struct bio *bio)
248{
249 unsigned segs = 0;
250 struct bio_vec bv;
251 struct bvec_iter iter;
252
Kent Overstreet8423ae32014-02-10 17:45:50 -0800253 /*
254 * We special case discard/write same, because they interpret bi_size
255 * differently:
256 */
257
258 if (bio->bi_rw & REQ_DISCARD)
259 return 1;
260
261 if (bio->bi_rw & REQ_WRITE_SAME)
262 return 1;
263
Kent Overstreet458b76e2013-09-24 16:26:05 -0700264 bio_for_each_segment(bv, bio, iter)
265 segs++;
266
267 return segs;
268}
269
Linus Torvalds1da177e2005-04-16 15:20:36 -0700270/*
271 * get a reference to a bio, so it won't disappear. the intended use is
272 * something like:
273 *
274 * bio_get(bio);
275 * submit_bio(rw, bio);
276 * if (bio->bi_flags ...)
277 * do_something
278 * bio_put(bio);
279 *
280 * without the bio_get(), it could potentially complete I/O before submit_bio
281 * returns. and then bio would be freed memory when if (bio->bi_flags ...)
282 * runs
283 */
284#define bio_get(bio) atomic_inc(&(bio)->bi_cnt)
285
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200286#if defined(CONFIG_BLK_DEV_INTEGRITY)
287/*
288 * bio integrity payload
289 */
290struct bio_integrity_payload {
291 struct bio *bip_bio; /* parent bio */
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200292
Kent Overstreetd57a5f72013-11-23 17:20:16 -0800293 struct bvec_iter bip_iter;
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200294
Kent Overstreetd57a5f72013-11-23 17:20:16 -0800295 /* kill - should just use bip_vec */
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200296 void *bip_buf; /* generated integrity data */
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200297
Kent Overstreetd57a5f72013-11-23 17:20:16 -0800298 bio_end_io_t *bip_end_io; /* saved I/O completion fn */
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200299
Martin K. Petersen7878cba2009-06-26 15:37:49 +0200300 unsigned short bip_slab; /* slab the bip came from */
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200301 unsigned short bip_vcnt; /* # of integrity bio_vecs */
Kent Overstreet29ed7812012-09-04 09:54:22 -0700302 unsigned bip_owns_buf:1; /* should free bip_buf */
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200303
304 struct work_struct bip_work; /* I/O completion */
Kent Overstreet6fda9812012-10-12 13:18:27 -0700305
306 struct bio_vec *bip_vec;
307 struct bio_vec bip_inline_vecs[0];/* embedded bvec array */
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200308};
309#endif /* CONFIG_BLK_DEV_INTEGRITY */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700310
Kent Overstreet6678d832013-08-07 11:14:32 -0700311extern void bio_trim(struct bio *bio, int offset, int size);
Kent Overstreet20d01892013-11-23 18:21:01 -0800312extern struct bio *bio_split(struct bio *bio, int sectors,
313 gfp_t gfp, struct bio_set *bs);
314
315/**
316 * bio_next_split - get next @sectors from a bio, splitting if necessary
317 * @bio: bio to split
318 * @sectors: number of sectors to split from the front of @bio
319 * @gfp: gfp mask
320 * @bs: bio set to allocate from
321 *
322 * Returns a bio representing the next @sectors of @bio - if the bio is smaller
323 * than @sectors, returns the original bio unchanged.
324 */
325static inline struct bio *bio_next_split(struct bio *bio, int sectors,
326 gfp_t gfp, struct bio_set *bs)
327{
328 if (sectors >= bio_sectors(bio))
329 return bio;
330
331 return bio_split(bio, sectors, gfp, bs);
332}
333
Jens Axboebb799ca2008-12-10 15:35:05 +0100334extern struct bio_set *bioset_create(unsigned int, unsigned int);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700335extern void bioset_free(struct bio_set *);
Kent Overstreet9f060e22012-10-12 15:29:33 -0700336extern mempool_t *biovec_create_pool(struct bio_set *bs, int pool_entries);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700337
Al Virodd0fc662005-10-07 07:46:04 +0100338extern struct bio *bio_alloc_bioset(gfp_t, int, struct bio_set *);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700339extern void bio_put(struct bio *);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700340
Kent Overstreet59d276f2013-11-23 18:19:27 -0800341extern void __bio_clone_fast(struct bio *, struct bio *);
342extern struct bio *bio_clone_fast(struct bio *, gfp_t, struct bio_set *);
Kent Overstreetbf800ef2012-09-06 15:35:02 -0700343extern struct bio *bio_clone_bioset(struct bio *, gfp_t, struct bio_set *bs);
344
Kent Overstreet3f86a822012-09-06 15:35:01 -0700345extern struct bio_set *fs_bio_set;
Rashika Kheriac4540a72014-02-09 18:30:39 +0530346unsigned int bio_integrity_tag_size(struct bio *bio);
Kent Overstreet3f86a822012-09-06 15:35:01 -0700347
348static inline struct bio *bio_alloc(gfp_t gfp_mask, unsigned int nr_iovecs)
349{
350 return bio_alloc_bioset(gfp_mask, nr_iovecs, fs_bio_set);
351}
352
Kent Overstreetbf800ef2012-09-06 15:35:02 -0700353static inline struct bio *bio_clone(struct bio *bio, gfp_t gfp_mask)
354{
355 return bio_clone_bioset(bio, gfp_mask, fs_bio_set);
356}
357
Kent Overstreet3f86a822012-09-06 15:35:01 -0700358static inline struct bio *bio_kmalloc(gfp_t gfp_mask, unsigned int nr_iovecs)
359{
360 return bio_alloc_bioset(gfp_mask, nr_iovecs, NULL);
361}
362
Kent Overstreetbf800ef2012-09-06 15:35:02 -0700363static inline struct bio *bio_clone_kmalloc(struct bio *bio, gfp_t gfp_mask)
364{
365 return bio_clone_bioset(bio, gfp_mask, NULL);
366
367}
368
NeilBrown6712ecf2007-09-27 12:47:43 +0200369extern void bio_endio(struct bio *, int);
Kent Overstreet196d38b2013-11-23 18:34:15 -0800370extern void bio_endio_nodec(struct bio *, int);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700371struct request_queue;
372extern int bio_phys_segments(struct request_queue *, struct bio *);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700373
Kent Overstreet9e882242012-09-10 14:41:12 -0700374extern int submit_bio_wait(int rw, struct bio *bio);
Kent Overstreet054bdf62012-09-28 13:17:55 -0700375extern void bio_advance(struct bio *, unsigned);
376
Linus Torvalds1da177e2005-04-16 15:20:36 -0700377extern void bio_init(struct bio *);
Kent Overstreetf44b48c2012-09-06 15:34:58 -0700378extern void bio_reset(struct bio *);
Kent Overstreet196d38b2013-11-23 18:34:15 -0800379void bio_chain(struct bio *, struct bio *);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700380
381extern int bio_add_page(struct bio *, struct page *, unsigned int,unsigned int);
Mike Christie6e68af62005-11-11 05:30:27 -0600382extern int bio_add_pc_page(struct request_queue *, struct bio *, struct page *,
383 unsigned int, unsigned int);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700384extern int bio_get_nr_vecs(struct block_device *);
385extern struct bio *bio_map_user(struct request_queue *, struct block_device *,
FUJITA Tomonoria3bce902008-08-28 16:17:05 +0900386 unsigned long, unsigned int, int, gfp_t);
James Bottomley f1970ba2005-06-20 14:06:52 +0200387struct sg_iovec;
FUJITA Tomonori152e2832008-08-28 16:17:06 +0900388struct rq_map_data;
James Bottomley f1970ba2005-06-20 14:06:52 +0200389extern struct bio *bio_map_user_iov(struct request_queue *,
390 struct block_device *,
FUJITA Tomonoria3bce902008-08-28 16:17:05 +0900391 struct sg_iovec *, int, int, gfp_t);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700392extern void bio_unmap_user(struct bio *);
Mike Christie df46b9a2005-06-20 14:04:44 +0200393extern struct bio *bio_map_kern(struct request_queue *, void *, unsigned int,
Al Viro27496a82005-10-21 03:20:48 -0400394 gfp_t);
FUJITA Tomonori68154e92008-04-25 12:47:50 +0200395extern struct bio *bio_copy_kern(struct request_queue *, void *, unsigned int,
396 gfp_t, int);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700397extern void bio_set_pages_dirty(struct bio *bio);
398extern void bio_check_pages_dirty(struct bio *bio);
Ilya Loginov2d4dc892009-11-26 09:16:19 +0100399
400#ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
401# error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform"
402#endif
403#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
404extern void bio_flush_dcache_pages(struct bio *bi);
405#else
406static inline void bio_flush_dcache_pages(struct bio *bi)
407{
408}
409#endif
410
Kent Overstreet16ac3d62012-09-10 13:57:51 -0700411extern void bio_copy_data(struct bio *dst, struct bio *src);
Kent Overstreeta0787602012-09-10 14:03:28 -0700412extern int bio_alloc_pages(struct bio *bio, gfp_t gfp);
Kent Overstreet16ac3d62012-09-10 13:57:51 -0700413
FUJITA Tomonori152e2832008-08-28 16:17:06 +0900414extern struct bio *bio_copy_user(struct request_queue *, struct rq_map_data *,
415 unsigned long, unsigned int, int, gfp_t);
416extern struct bio *bio_copy_user_iov(struct request_queue *,
417 struct rq_map_data *, struct sg_iovec *,
FUJITA Tomonoria3bce902008-08-28 16:17:05 +0900418 int, int, gfp_t);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700419extern int bio_uncopy_user(struct bio *);
420void zero_fill_bio(struct bio *bio);
Kent Overstreet9f060e22012-10-12 15:29:33 -0700421extern struct bio_vec *bvec_alloc(gfp_t, int, unsigned long *, mempool_t *);
422extern void bvec_free(mempool_t *, struct bio_vec *, unsigned int);
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200423extern unsigned int bvec_nr_vecs(unsigned short idx);
Martin K. Petersen51d654e2008-06-17 18:59:56 +0200424
Tejun Heo852c7882012-03-05 13:15:27 -0800425#ifdef CONFIG_BLK_CGROUP
426int bio_associate_current(struct bio *bio);
427void bio_disassociate_task(struct bio *bio);
428#else /* CONFIG_BLK_CGROUP */
429static inline int bio_associate_current(struct bio *bio) { return -ENOENT; }
430static inline void bio_disassociate_task(struct bio *bio) { }
431#endif /* CONFIG_BLK_CGROUP */
432
Linus Torvalds1da177e2005-04-16 15:20:36 -0700433#ifdef CONFIG_HIGHMEM
434/*
Alberto Bertogli20b636b2009-02-02 12:41:07 +0100435 * remember never ever reenable interrupts between a bvec_kmap_irq and
436 * bvec_kunmap_irq!
Linus Torvalds1da177e2005-04-16 15:20:36 -0700437 */
Alberto Bertogli4f570f92009-11-02 11:40:16 +0100438static inline char *bvec_kmap_irq(struct bio_vec *bvec, unsigned long *flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700439{
440 unsigned long addr;
441
442 /*
443 * might not be a highmem page, but the preempt/irq count
444 * balancing is a lot nicer this way
445 */
446 local_irq_save(*flags);
Cong Wange8e3c3d2011-11-25 23:14:27 +0800447 addr = (unsigned long) kmap_atomic(bvec->bv_page);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700448
449 BUG_ON(addr & ~PAGE_MASK);
450
451 return (char *) addr + bvec->bv_offset;
452}
453
Alberto Bertogli4f570f92009-11-02 11:40:16 +0100454static inline void bvec_kunmap_irq(char *buffer, unsigned long *flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700455{
456 unsigned long ptr = (unsigned long) buffer & PAGE_MASK;
457
Cong Wange8e3c3d2011-11-25 23:14:27 +0800458 kunmap_atomic((void *) ptr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700459 local_irq_restore(*flags);
460}
461
462#else
Geert Uytterhoeven11a691b2010-10-21 10:32:29 +0200463static inline char *bvec_kmap_irq(struct bio_vec *bvec, unsigned long *flags)
464{
465 return page_address(bvec->bv_page) + bvec->bv_offset;
466}
467
468static inline void bvec_kunmap_irq(char *buffer, unsigned long *flags)
469{
470 *flags = 0;
471}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700472#endif
473
Kent Overstreetf619d252013-08-07 14:30:33 -0700474static inline char *__bio_kmap_irq(struct bio *bio, struct bvec_iter iter,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700475 unsigned long *flags)
476{
Kent Overstreetf619d252013-08-07 14:30:33 -0700477 return bvec_kmap_irq(&bio_iter_iovec(bio, iter), flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700478}
479#define __bio_kunmap_irq(buf, flags) bvec_kunmap_irq(buf, flags)
480
481#define bio_kmap_irq(bio, flags) \
Kent Overstreetf619d252013-08-07 14:30:33 -0700482 __bio_kmap_irq((bio), (bio)->bi_iter, (flags))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700483#define bio_kunmap_irq(buf,flags) __bio_kunmap_irq(buf, flags)
484
Jens Axboe7a67f632008-08-08 11:17:12 +0200485/*
Akinobu Mitae6863072009-04-17 08:41:21 +0200486 * BIO list management for use by remapping drivers (e.g. DM or MD) and loop.
Christoph Hellwig8f3d8ba2009-04-07 19:55:13 +0200487 *
488 * A bio_list anchors a singly-linked list of bios chained through the bi_next
489 * member of the bio. The bio_list also caches the last list member to allow
490 * fast access to the tail.
491 */
492struct bio_list {
493 struct bio *head;
494 struct bio *tail;
495};
496
497static inline int bio_list_empty(const struct bio_list *bl)
498{
499 return bl->head == NULL;
500}
501
502static inline void bio_list_init(struct bio_list *bl)
503{
504 bl->head = bl->tail = NULL;
505}
506
Jens Axboe320ae512013-10-24 09:20:05 +0100507#define BIO_EMPTY_LIST { NULL, NULL }
508
Christoph Hellwig8f3d8ba2009-04-07 19:55:13 +0200509#define bio_list_for_each(bio, bl) \
510 for (bio = (bl)->head; bio; bio = bio->bi_next)
511
512static inline unsigned bio_list_size(const struct bio_list *bl)
513{
514 unsigned sz = 0;
515 struct bio *bio;
516
517 bio_list_for_each(bio, bl)
518 sz++;
519
520 return sz;
521}
522
523static inline void bio_list_add(struct bio_list *bl, struct bio *bio)
524{
525 bio->bi_next = NULL;
526
527 if (bl->tail)
528 bl->tail->bi_next = bio;
529 else
530 bl->head = bio;
531
532 bl->tail = bio;
533}
534
535static inline void bio_list_add_head(struct bio_list *bl, struct bio *bio)
536{
537 bio->bi_next = bl->head;
538
539 bl->head = bio;
540
541 if (!bl->tail)
542 bl->tail = bio;
543}
544
545static inline void bio_list_merge(struct bio_list *bl, struct bio_list *bl2)
546{
547 if (!bl2->head)
548 return;
549
550 if (bl->tail)
551 bl->tail->bi_next = bl2->head;
552 else
553 bl->head = bl2->head;
554
555 bl->tail = bl2->tail;
556}
557
558static inline void bio_list_merge_head(struct bio_list *bl,
559 struct bio_list *bl2)
560{
561 if (!bl2->head)
562 return;
563
564 if (bl->head)
565 bl2->tail->bi_next = bl->head;
566 else
567 bl->tail = bl2->tail;
568
569 bl->head = bl2->head;
570}
571
Geert Uytterhoeven13685a12009-06-10 04:38:40 +0000572static inline struct bio *bio_list_peek(struct bio_list *bl)
573{
574 return bl->head;
575}
576
Christoph Hellwig8f3d8ba2009-04-07 19:55:13 +0200577static inline struct bio *bio_list_pop(struct bio_list *bl)
578{
579 struct bio *bio = bl->head;
580
581 if (bio) {
582 bl->head = bl->head->bi_next;
583 if (!bl->head)
584 bl->tail = NULL;
585
586 bio->bi_next = NULL;
587 }
588
589 return bio;
590}
591
592static inline struct bio *bio_list_get(struct bio_list *bl)
593{
594 struct bio *bio = bl->head;
595
596 bl->head = bl->tail = NULL;
597
598 return bio;
599}
600
Kent Overstreet57fb2332012-08-24 04:56:11 -0700601/*
602 * bio_set is used to allow other portions of the IO system to
603 * allocate their own private memory pools for bio and iovec structures.
604 * These memory pools in turn all allocate from the bio_slab
605 * and the bvec_slabs[].
606 */
607#define BIO_POOL_SIZE 2
608#define BIOVEC_NR_POOLS 6
609#define BIOVEC_MAX_IDX (BIOVEC_NR_POOLS - 1)
610
611struct bio_set {
612 struct kmem_cache *bio_slab;
613 unsigned int front_pad;
614
615 mempool_t *bio_pool;
Kent Overstreet9f060e22012-10-12 15:29:33 -0700616 mempool_t *bvec_pool;
Kent Overstreet57fb2332012-08-24 04:56:11 -0700617#if defined(CONFIG_BLK_DEV_INTEGRITY)
618 mempool_t *bio_integrity_pool;
Kent Overstreet9f060e22012-10-12 15:29:33 -0700619 mempool_t *bvec_integrity_pool;
Kent Overstreet57fb2332012-08-24 04:56:11 -0700620#endif
Kent Overstreetdf2cb6d2012-09-10 14:33:46 -0700621
622 /*
623 * Deadlock avoidance for stacking block drivers: see comments in
624 * bio_alloc_bioset() for details
625 */
626 spinlock_t rescue_lock;
627 struct bio_list rescue_list;
628 struct work_struct rescue_work;
629 struct workqueue_struct *rescue_workqueue;
Kent Overstreet57fb2332012-08-24 04:56:11 -0700630};
631
632struct biovec_slab {
633 int nr_vecs;
634 char *name;
635 struct kmem_cache *slab;
636};
637
638/*
639 * a small number of entries is fine, not going to be performance critical.
640 * basically we just need to survive
641 */
642#define BIO_SPLIT_ENTRIES 2
643
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200644#if defined(CONFIG_BLK_DEV_INTEGRITY)
645
Kent Overstreetd57a5f72013-11-23 17:20:16 -0800646
647
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200648#define bip_vec_idx(bip, idx) (&(bip->bip_vec[(idx)]))
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200649
Kent Overstreetd57a5f72013-11-23 17:20:16 -0800650#define bip_for_each_vec(bvl, bip, iter) \
651 for_each_bvec(bvl, (bip)->bip_vec, iter, (bip)->bip_iter)
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200652
Martin K. Petersen13f05c82010-09-10 20:50:10 +0200653#define bio_for_each_integrity_vec(_bvl, _bio, _iter) \
654 for_each_bio(_bio) \
655 bip_for_each_vec(_bvl, _bio->bi_integrity, _iter)
656
Alberto Bertogli8deaf722008-10-02 12:46:53 +0200657#define bio_integrity(bio) (bio->bi_integrity != NULL)
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200658
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200659extern struct bio_integrity_payload *bio_integrity_alloc(struct bio *, gfp_t, unsigned int);
Kent Overstreet1e2a410f2012-09-06 15:34:56 -0700660extern void bio_integrity_free(struct bio *);
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200661extern int bio_integrity_add_page(struct bio *, struct page *, unsigned int, unsigned int);
662extern int bio_integrity_enabled(struct bio *bio);
663extern int bio_integrity_set_tag(struct bio *, void *, unsigned int);
664extern int bio_integrity_get_tag(struct bio *, void *, unsigned int);
665extern int bio_integrity_prep(struct bio *);
666extern void bio_integrity_endio(struct bio *, int);
667extern void bio_integrity_advance(struct bio *, unsigned int);
668extern void bio_integrity_trim(struct bio *, unsigned int, unsigned int);
Kent Overstreet1e2a410f2012-09-06 15:34:56 -0700669extern int bio_integrity_clone(struct bio *, struct bio *, gfp_t);
Martin K. Petersen7878cba2009-06-26 15:37:49 +0200670extern int bioset_integrity_create(struct bio_set *, int);
671extern void bioset_integrity_free(struct bio_set *);
672extern void bio_integrity_init(void);
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200673
674#else /* CONFIG_BLK_DEV_INTEGRITY */
675
Martin K. Petersen6898e3b2012-01-13 08:15:33 +0100676static inline int bio_integrity(struct bio *bio)
677{
678 return 0;
679}
680
681static inline int bio_integrity_enabled(struct bio *bio)
682{
683 return 0;
684}
685
686static inline int bioset_integrity_create(struct bio_set *bs, int pool_size)
687{
688 return 0;
689}
690
691static inline void bioset_integrity_free (struct bio_set *bs)
692{
693 return;
694}
695
696static inline int bio_integrity_prep(struct bio *bio)
697{
698 return 0;
699}
700
Kent Overstreet1e2a410f2012-09-06 15:34:56 -0700701static inline void bio_integrity_free(struct bio *bio)
Martin K. Petersen6898e3b2012-01-13 08:15:33 +0100702{
703 return;
704}
705
Stephen Rothwell0c614e22011-11-16 09:21:48 +0100706static inline int bio_integrity_clone(struct bio *bio, struct bio *bio_src,
Kent Overstreet1e2a410f2012-09-06 15:34:56 -0700707 gfp_t gfp_mask)
Stephen Rothwell0c614e22011-11-16 09:21:48 +0100708{
709 return 0;
710}
Martin K. Petersen6898e3b2012-01-13 08:15:33 +0100711
Martin K. Petersen6898e3b2012-01-13 08:15:33 +0100712static inline void bio_integrity_advance(struct bio *bio,
713 unsigned int bytes_done)
714{
715 return;
716}
717
718static inline void bio_integrity_trim(struct bio *bio, unsigned int offset,
719 unsigned int sectors)
720{
721 return;
722}
723
724static inline void bio_integrity_init(void)
725{
726 return;
727}
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200728
729#endif /* CONFIG_BLK_DEV_INTEGRITY */
730
David Howells02a5e0a2007-08-11 22:34:32 +0200731#endif /* CONFIG_BLOCK */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700732#endif /* __LINUX_BIO_H */