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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
Jens Axboe66cb45a2014-06-24 16:22:24 -0600189/*
190 * Check if adding a bio_vec after bprv with offset would create a gap in
191 * the SG list. Most drivers don't care about this, but some do.
192 */
193static inline bool bvec_gap_to_prev(struct bio_vec *bprv, unsigned int offset)
194{
195 return offset || ((bprv->bv_offset + bprv->bv_len) & (PAGE_SIZE - 1));
196}
197
NeilBrown6712ecf2007-09-27 12:47:43 +0200198#define bio_io_error(bio) bio_endio((bio), -EIO)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700199
200/*
Kent Overstreetd74c6d52013-02-06 12:23:11 -0800201 * drivers should _never_ use the all version - the bio may have been split
202 * before it got to the driver and the driver won't own all of it
203 */
204#define bio_for_each_segment_all(bvl, bio, i) \
Kent Overstreetf619d252013-08-07 14:30:33 -0700205 for (i = 0, bvl = (bio)->bi_io_vec; i < (bio)->bi_vcnt; i++, bvl++)
Kent Overstreetd74c6d52013-02-06 12:23:11 -0800206
Kent Overstreet4550dd62013-08-07 14:26:21 -0700207static inline void bvec_iter_advance(struct bio_vec *bv, struct bvec_iter *iter,
208 unsigned bytes)
209{
210 WARN_ONCE(bytes > iter->bi_size,
211 "Attempted to advance past end of bvec iter\n");
212
213 while (bytes) {
214 unsigned len = min(bytes, bvec_iter_len(bv, *iter));
215
216 bytes -= len;
217 iter->bi_size -= len;
218 iter->bi_bvec_done += len;
219
220 if (iter->bi_bvec_done == __bvec_iter_bvec(bv, *iter)->bv_len) {
221 iter->bi_bvec_done = 0;
222 iter->bi_idx++;
223 }
224 }
225}
226
227#define for_each_bvec(bvl, bio_vec, iter, start) \
Martin K. Petersenb7aa84d2014-04-08 22:43:43 -0400228 for (iter = (start); \
229 (iter).bi_size && \
230 ((bvl = bvec_iter_bvec((bio_vec), (iter))), 1); \
Kent Overstreet4550dd62013-08-07 14:26:21 -0700231 bvec_iter_advance((bio_vec), &(iter), (bvl).bv_len))
232
233
234static inline void bio_advance_iter(struct bio *bio, struct bvec_iter *iter,
235 unsigned bytes)
236{
237 iter->bi_sector += bytes >> 9;
238
239 if (bio->bi_rw & BIO_NO_ADVANCE_ITER_MASK)
240 iter->bi_size -= bytes;
241 else
242 bvec_iter_advance(bio->bi_io_vec, iter, bytes);
243}
244
Kent Overstreet79886132013-11-23 17:19:00 -0800245#define __bio_for_each_segment(bvl, bio, iter, start) \
246 for (iter = (start); \
Kent Overstreet4550dd62013-08-07 14:26:21 -0700247 (iter).bi_size && \
248 ((bvl = bio_iter_iovec((bio), (iter))), 1); \
249 bio_advance_iter((bio), &(iter), (bvl).bv_len))
Kent Overstreet79886132013-11-23 17:19:00 -0800250
251#define bio_for_each_segment(bvl, bio, iter) \
252 __bio_for_each_segment(bvl, bio, iter, (bio)->bi_iter)
253
Kent Overstreet4550dd62013-08-07 14:26:21 -0700254#define bio_iter_last(bvec, iter) ((iter).bi_size == (bvec).bv_len)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700255
Kent Overstreet458b76e2013-09-24 16:26:05 -0700256static inline unsigned bio_segments(struct bio *bio)
257{
258 unsigned segs = 0;
259 struct bio_vec bv;
260 struct bvec_iter iter;
261
Kent Overstreet8423ae32014-02-10 17:45:50 -0800262 /*
263 * We special case discard/write same, because they interpret bi_size
264 * differently:
265 */
266
267 if (bio->bi_rw & REQ_DISCARD)
268 return 1;
269
270 if (bio->bi_rw & REQ_WRITE_SAME)
271 return 1;
272
Kent Overstreet458b76e2013-09-24 16:26:05 -0700273 bio_for_each_segment(bv, bio, iter)
274 segs++;
275
276 return segs;
277}
278
Linus Torvalds1da177e2005-04-16 15:20:36 -0700279/*
280 * get a reference to a bio, so it won't disappear. the intended use is
281 * something like:
282 *
283 * bio_get(bio);
284 * submit_bio(rw, bio);
285 * if (bio->bi_flags ...)
286 * do_something
287 * bio_put(bio);
288 *
289 * without the bio_get(), it could potentially complete I/O before submit_bio
290 * returns. and then bio would be freed memory when if (bio->bi_flags ...)
291 * runs
292 */
293#define bio_get(bio) atomic_inc(&(bio)->bi_cnt)
294
Martin K. Petersenc6115292014-09-26 19:20:08 -0400295enum bip_flags {
296 BIP_BLOCK_INTEGRITY = 1 << 0, /* block layer owns integrity data */
297 BIP_MAPPED_INTEGRITY = 1 << 1, /* ref tag has been remapped */
298 BIP_CTRL_NOCHECK = 1 << 2, /* disable HBA integrity checking */
299 BIP_DISK_NOCHECK = 1 << 3, /* disable disk integrity checking */
300 BIP_IP_CHECKSUM = 1 << 4, /* IP checksum */
301};
302
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200303#if defined(CONFIG_BLK_DEV_INTEGRITY)
Martin K. Petersen180b2f92014-09-26 19:19:56 -0400304
305static inline struct bio_integrity_payload *bio_integrity(struct bio *bio)
306{
307 if (bio->bi_rw & REQ_INTEGRITY)
308 return bio->bi_integrity;
309
310 return NULL;
311}
312
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200313/*
314 * bio integrity payload
315 */
316struct bio_integrity_payload {
317 struct bio *bip_bio; /* parent bio */
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200318
Kent Overstreetd57a5f72013-11-23 17:20:16 -0800319 struct bvec_iter bip_iter;
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200320
Kent Overstreetd57a5f72013-11-23 17:20:16 -0800321 bio_end_io_t *bip_end_io; /* saved I/O completion fn */
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200322
Martin K. Petersen7878cba2009-06-26 15:37:49 +0200323 unsigned short bip_slab; /* slab the bip came from */
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200324 unsigned short bip_vcnt; /* # of integrity bio_vecs */
Gu Zhengcbcd10542014-07-01 10:36:47 -0600325 unsigned short bip_max_vcnt; /* integrity bio_vec slots */
Martin K. Petersenb1f0138852014-09-26 19:20:04 -0400326 unsigned short bip_flags; /* control flags */
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200327
328 struct work_struct bip_work; /* I/O completion */
Kent Overstreet6fda9812012-10-12 13:18:27 -0700329
330 struct bio_vec *bip_vec;
331 struct bio_vec bip_inline_vecs[0];/* embedded bvec array */
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200332};
Martin K. Petersen18593082014-09-26 19:20:01 -0400333
Martin K. Petersenc6115292014-09-26 19:20:08 -0400334static inline bool bio_integrity_flagged(struct bio *bio, enum bip_flags flag)
335{
336 struct bio_integrity_payload *bip = bio_integrity(bio);
337
338 if (bip)
339 return bip->bip_flags & flag;
340
341 return false;
342}
Martin K. Petersenb1f0138852014-09-26 19:20:04 -0400343
Martin K. Petersen18593082014-09-26 19:20:01 -0400344static inline sector_t bip_get_seed(struct bio_integrity_payload *bip)
345{
346 return bip->bip_iter.bi_sector;
347}
348
349static inline void bip_set_seed(struct bio_integrity_payload *bip,
350 sector_t seed)
351{
352 bip->bip_iter.bi_sector = seed;
353}
354
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200355#endif /* CONFIG_BLK_DEV_INTEGRITY */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700356
Kent Overstreet6678d832013-08-07 11:14:32 -0700357extern void bio_trim(struct bio *bio, int offset, int size);
Kent Overstreet20d01892013-11-23 18:21:01 -0800358extern struct bio *bio_split(struct bio *bio, int sectors,
359 gfp_t gfp, struct bio_set *bs);
360
361/**
362 * bio_next_split - get next @sectors from a bio, splitting if necessary
363 * @bio: bio to split
364 * @sectors: number of sectors to split from the front of @bio
365 * @gfp: gfp mask
366 * @bs: bio set to allocate from
367 *
368 * Returns a bio representing the next @sectors of @bio - if the bio is smaller
369 * than @sectors, returns the original bio unchanged.
370 */
371static inline struct bio *bio_next_split(struct bio *bio, int sectors,
372 gfp_t gfp, struct bio_set *bs)
373{
374 if (sectors >= bio_sectors(bio))
375 return bio;
376
377 return bio_split(bio, sectors, gfp, bs);
378}
379
Jens Axboebb799ca2008-12-10 15:35:05 +0100380extern struct bio_set *bioset_create(unsigned int, unsigned int);
Junichi Nomurad8f429e2014-10-03 17:27:12 -0400381extern struct bio_set *bioset_create_nobvec(unsigned int, unsigned int);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700382extern void bioset_free(struct bio_set *);
Fabian Fredericka6c39cb4f2014-04-22 15:09:05 -0600383extern mempool_t *biovec_create_pool(int pool_entries);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700384
Al Virodd0fc662005-10-07 07:46:04 +0100385extern struct bio *bio_alloc_bioset(gfp_t, int, struct bio_set *);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700386extern void bio_put(struct bio *);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700387
Kent Overstreet59d276f2013-11-23 18:19:27 -0800388extern void __bio_clone_fast(struct bio *, struct bio *);
389extern struct bio *bio_clone_fast(struct bio *, gfp_t, struct bio_set *);
Kent Overstreetbf800ef2012-09-06 15:35:02 -0700390extern struct bio *bio_clone_bioset(struct bio *, gfp_t, struct bio_set *bs);
391
Kent Overstreet3f86a822012-09-06 15:35:01 -0700392extern struct bio_set *fs_bio_set;
393
394static inline struct bio *bio_alloc(gfp_t gfp_mask, unsigned int nr_iovecs)
395{
396 return bio_alloc_bioset(gfp_mask, nr_iovecs, fs_bio_set);
397}
398
Kent Overstreetbf800ef2012-09-06 15:35:02 -0700399static inline struct bio *bio_clone(struct bio *bio, gfp_t gfp_mask)
400{
401 return bio_clone_bioset(bio, gfp_mask, fs_bio_set);
402}
403
Kent Overstreet3f86a822012-09-06 15:35:01 -0700404static inline struct bio *bio_kmalloc(gfp_t gfp_mask, unsigned int nr_iovecs)
405{
406 return bio_alloc_bioset(gfp_mask, nr_iovecs, NULL);
407}
408
Kent Overstreetbf800ef2012-09-06 15:35:02 -0700409static inline struct bio *bio_clone_kmalloc(struct bio *bio, gfp_t gfp_mask)
410{
411 return bio_clone_bioset(bio, gfp_mask, NULL);
412
413}
414
NeilBrown6712ecf2007-09-27 12:47:43 +0200415extern void bio_endio(struct bio *, int);
Kent Overstreet196d38b2013-11-23 18:34:15 -0800416extern void bio_endio_nodec(struct bio *, int);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700417struct request_queue;
418extern int bio_phys_segments(struct request_queue *, struct bio *);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700419
Kent Overstreet9e882242012-09-10 14:41:12 -0700420extern int submit_bio_wait(int rw, struct bio *bio);
Kent Overstreet054bdf62012-09-28 13:17:55 -0700421extern void bio_advance(struct bio *, unsigned);
422
Linus Torvalds1da177e2005-04-16 15:20:36 -0700423extern void bio_init(struct bio *);
Kent Overstreetf44b48c2012-09-06 15:34:58 -0700424extern void bio_reset(struct bio *);
Kent Overstreet196d38b2013-11-23 18:34:15 -0800425void bio_chain(struct bio *, struct bio *);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700426
427extern int bio_add_page(struct bio *, struct page *, unsigned int,unsigned int);
Mike Christie6e68af62005-11-11 05:30:27 -0600428extern int bio_add_pc_page(struct request_queue *, struct bio *, struct page *,
429 unsigned int, unsigned int);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700430extern int bio_get_nr_vecs(struct block_device *);
FUJITA Tomonori152e2832008-08-28 16:17:06 +0900431struct rq_map_data;
James Bottomley f1970ba2005-06-20 14:06:52 +0200432extern struct bio *bio_map_user_iov(struct request_queue *,
Kent Overstreet26e49cf2015-01-18 16:16:31 +0100433 const struct iov_iter *, gfp_t);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700434extern void bio_unmap_user(struct bio *);
Mike Christie df46b9a2005-06-20 14:04:44 +0200435extern struct bio *bio_map_kern(struct request_queue *, void *, unsigned int,
Al Viro27496a82005-10-21 03:20:48 -0400436 gfp_t);
FUJITA Tomonori68154e92008-04-25 12:47:50 +0200437extern struct bio *bio_copy_kern(struct request_queue *, void *, unsigned int,
438 gfp_t, int);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700439extern void bio_set_pages_dirty(struct bio *bio);
440extern void bio_check_pages_dirty(struct bio *bio);
Ilya Loginov2d4dc892009-11-26 09:16:19 +0100441
Gu Zheng394ffa52014-11-24 11:05:22 +0800442void generic_start_io_acct(int rw, unsigned long sectors,
443 struct hd_struct *part);
444void generic_end_io_acct(int rw, struct hd_struct *part,
445 unsigned long start_time);
446
Ilya Loginov2d4dc892009-11-26 09:16:19 +0100447#ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
448# error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform"
449#endif
450#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
451extern void bio_flush_dcache_pages(struct bio *bi);
452#else
453static inline void bio_flush_dcache_pages(struct bio *bi)
454{
455}
456#endif
457
Kent Overstreet16ac3d62012-09-10 13:57:51 -0700458extern void bio_copy_data(struct bio *dst, struct bio *src);
Kent Overstreeta0787602012-09-10 14:03:28 -0700459extern int bio_alloc_pages(struct bio *bio, gfp_t gfp);
Kent Overstreet16ac3d62012-09-10 13:57:51 -0700460
FUJITA Tomonori152e2832008-08-28 16:17:06 +0900461extern struct bio *bio_copy_user_iov(struct request_queue *,
Al Viro86d564c2014-02-08 20:42:52 -0500462 struct rq_map_data *,
Kent Overstreet26e49cf2015-01-18 16:16:31 +0100463 const struct iov_iter *,
464 gfp_t);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700465extern int bio_uncopy_user(struct bio *);
466void zero_fill_bio(struct bio *bio);
Kent Overstreet9f060e22012-10-12 15:29:33 -0700467extern struct bio_vec *bvec_alloc(gfp_t, int, unsigned long *, mempool_t *);
468extern void bvec_free(mempool_t *, struct bio_vec *, unsigned int);
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200469extern unsigned int bvec_nr_vecs(unsigned short idx);
Martin K. Petersen51d654e2008-06-17 18:59:56 +0200470
Tejun Heo852c7882012-03-05 13:15:27 -0800471#ifdef CONFIG_BLK_CGROUP
Tejun Heo94d61b22015-05-22 17:13:24 -0400472int bio_associate_blkcg(struct bio *bio, struct cgroup_subsys_state *blkcg_css);
Tejun Heo852c7882012-03-05 13:15:27 -0800473int bio_associate_current(struct bio *bio);
474void bio_disassociate_task(struct bio *bio);
475#else /* CONFIG_BLK_CGROUP */
Tejun Heo94d61b22015-05-22 17:13:24 -0400476static inline int bio_associate_blkcg(struct bio *bio,
477 struct cgroup_subsys_state *blkcg_css) { return 0; }
Tejun Heo852c7882012-03-05 13:15:27 -0800478static inline int bio_associate_current(struct bio *bio) { return -ENOENT; }
479static inline void bio_disassociate_task(struct bio *bio) { }
480#endif /* CONFIG_BLK_CGROUP */
481
Linus Torvalds1da177e2005-04-16 15:20:36 -0700482#ifdef CONFIG_HIGHMEM
483/*
Alberto Bertogli20b636b2009-02-02 12:41:07 +0100484 * remember never ever reenable interrupts between a bvec_kmap_irq and
485 * bvec_kunmap_irq!
Linus Torvalds1da177e2005-04-16 15:20:36 -0700486 */
Alberto Bertogli4f570f92009-11-02 11:40:16 +0100487static inline char *bvec_kmap_irq(struct bio_vec *bvec, unsigned long *flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700488{
489 unsigned long addr;
490
491 /*
492 * might not be a highmem page, but the preempt/irq count
493 * balancing is a lot nicer this way
494 */
495 local_irq_save(*flags);
Cong Wange8e3c3d2011-11-25 23:14:27 +0800496 addr = (unsigned long) kmap_atomic(bvec->bv_page);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700497
498 BUG_ON(addr & ~PAGE_MASK);
499
500 return (char *) addr + bvec->bv_offset;
501}
502
Alberto Bertogli4f570f92009-11-02 11:40:16 +0100503static inline void bvec_kunmap_irq(char *buffer, unsigned long *flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700504{
505 unsigned long ptr = (unsigned long) buffer & PAGE_MASK;
506
Cong Wange8e3c3d2011-11-25 23:14:27 +0800507 kunmap_atomic((void *) ptr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700508 local_irq_restore(*flags);
509}
510
511#else
Geert Uytterhoeven11a691b2010-10-21 10:32:29 +0200512static inline char *bvec_kmap_irq(struct bio_vec *bvec, unsigned long *flags)
513{
514 return page_address(bvec->bv_page) + bvec->bv_offset;
515}
516
517static inline void bvec_kunmap_irq(char *buffer, unsigned long *flags)
518{
519 *flags = 0;
520}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700521#endif
522
Kent Overstreetf619d252013-08-07 14:30:33 -0700523static inline char *__bio_kmap_irq(struct bio *bio, struct bvec_iter iter,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700524 unsigned long *flags)
525{
Kent Overstreetf619d252013-08-07 14:30:33 -0700526 return bvec_kmap_irq(&bio_iter_iovec(bio, iter), flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700527}
528#define __bio_kunmap_irq(buf, flags) bvec_kunmap_irq(buf, flags)
529
530#define bio_kmap_irq(bio, flags) \
Kent Overstreetf619d252013-08-07 14:30:33 -0700531 __bio_kmap_irq((bio), (bio)->bi_iter, (flags))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700532#define bio_kunmap_irq(buf,flags) __bio_kunmap_irq(buf, flags)
533
Jens Axboe7a67f632008-08-08 11:17:12 +0200534/*
Akinobu Mitae6863072009-04-17 08:41:21 +0200535 * BIO list management for use by remapping drivers (e.g. DM or MD) and loop.
Christoph Hellwig8f3d8ba2009-04-07 19:55:13 +0200536 *
537 * A bio_list anchors a singly-linked list of bios chained through the bi_next
538 * member of the bio. The bio_list also caches the last list member to allow
539 * fast access to the tail.
540 */
541struct bio_list {
542 struct bio *head;
543 struct bio *tail;
544};
545
546static inline int bio_list_empty(const struct bio_list *bl)
547{
548 return bl->head == NULL;
549}
550
551static inline void bio_list_init(struct bio_list *bl)
552{
553 bl->head = bl->tail = NULL;
554}
555
Jens Axboe320ae512013-10-24 09:20:05 +0100556#define BIO_EMPTY_LIST { NULL, NULL }
557
Christoph Hellwig8f3d8ba2009-04-07 19:55:13 +0200558#define bio_list_for_each(bio, bl) \
559 for (bio = (bl)->head; bio; bio = bio->bi_next)
560
561static inline unsigned bio_list_size(const struct bio_list *bl)
562{
563 unsigned sz = 0;
564 struct bio *bio;
565
566 bio_list_for_each(bio, bl)
567 sz++;
568
569 return sz;
570}
571
572static inline void bio_list_add(struct bio_list *bl, struct bio *bio)
573{
574 bio->bi_next = NULL;
575
576 if (bl->tail)
577 bl->tail->bi_next = bio;
578 else
579 bl->head = bio;
580
581 bl->tail = bio;
582}
583
584static inline void bio_list_add_head(struct bio_list *bl, struct bio *bio)
585{
586 bio->bi_next = bl->head;
587
588 bl->head = bio;
589
590 if (!bl->tail)
591 bl->tail = bio;
592}
593
594static inline void bio_list_merge(struct bio_list *bl, struct bio_list *bl2)
595{
596 if (!bl2->head)
597 return;
598
599 if (bl->tail)
600 bl->tail->bi_next = bl2->head;
601 else
602 bl->head = bl2->head;
603
604 bl->tail = bl2->tail;
605}
606
607static inline void bio_list_merge_head(struct bio_list *bl,
608 struct bio_list *bl2)
609{
610 if (!bl2->head)
611 return;
612
613 if (bl->head)
614 bl2->tail->bi_next = bl->head;
615 else
616 bl->tail = bl2->tail;
617
618 bl->head = bl2->head;
619}
620
Geert Uytterhoeven13685a12009-06-10 04:38:40 +0000621static inline struct bio *bio_list_peek(struct bio_list *bl)
622{
623 return bl->head;
624}
625
Christoph Hellwig8f3d8ba2009-04-07 19:55:13 +0200626static inline struct bio *bio_list_pop(struct bio_list *bl)
627{
628 struct bio *bio = bl->head;
629
630 if (bio) {
631 bl->head = bl->head->bi_next;
632 if (!bl->head)
633 bl->tail = NULL;
634
635 bio->bi_next = NULL;
636 }
637
638 return bio;
639}
640
641static inline struct bio *bio_list_get(struct bio_list *bl)
642{
643 struct bio *bio = bl->head;
644
645 bl->head = bl->tail = NULL;
646
647 return bio;
648}
649
Kent Overstreet57fb2332012-08-24 04:56:11 -0700650/*
651 * bio_set is used to allow other portions of the IO system to
652 * allocate their own private memory pools for bio and iovec structures.
653 * These memory pools in turn all allocate from the bio_slab
654 * and the bvec_slabs[].
655 */
656#define BIO_POOL_SIZE 2
657#define BIOVEC_NR_POOLS 6
658#define BIOVEC_MAX_IDX (BIOVEC_NR_POOLS - 1)
659
660struct bio_set {
661 struct kmem_cache *bio_slab;
662 unsigned int front_pad;
663
664 mempool_t *bio_pool;
Kent Overstreet9f060e22012-10-12 15:29:33 -0700665 mempool_t *bvec_pool;
Kent Overstreet57fb2332012-08-24 04:56:11 -0700666#if defined(CONFIG_BLK_DEV_INTEGRITY)
667 mempool_t *bio_integrity_pool;
Kent Overstreet9f060e22012-10-12 15:29:33 -0700668 mempool_t *bvec_integrity_pool;
Kent Overstreet57fb2332012-08-24 04:56:11 -0700669#endif
Kent Overstreetdf2cb6d2012-09-10 14:33:46 -0700670
671 /*
672 * Deadlock avoidance for stacking block drivers: see comments in
673 * bio_alloc_bioset() for details
674 */
675 spinlock_t rescue_lock;
676 struct bio_list rescue_list;
677 struct work_struct rescue_work;
678 struct workqueue_struct *rescue_workqueue;
Kent Overstreet57fb2332012-08-24 04:56:11 -0700679};
680
681struct biovec_slab {
682 int nr_vecs;
683 char *name;
684 struct kmem_cache *slab;
685};
686
687/*
688 * a small number of entries is fine, not going to be performance critical.
689 * basically we just need to survive
690 */
691#define BIO_SPLIT_ENTRIES 2
692
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200693#if defined(CONFIG_BLK_DEV_INTEGRITY)
694
Kent Overstreetd57a5f72013-11-23 17:20:16 -0800695#define bip_for_each_vec(bvl, bip, iter) \
696 for_each_bvec(bvl, (bip)->bip_vec, iter, (bip)->bip_iter)
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200697
Martin K. Petersen13f05c82010-09-10 20:50:10 +0200698#define bio_for_each_integrity_vec(_bvl, _bio, _iter) \
699 for_each_bio(_bio) \
700 bip_for_each_vec(_bvl, _bio->bi_integrity, _iter)
701
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200702extern struct bio_integrity_payload *bio_integrity_alloc(struct bio *, gfp_t, unsigned int);
Kent Overstreet1e2a410f2012-09-06 15:34:56 -0700703extern void bio_integrity_free(struct bio *);
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200704extern int bio_integrity_add_page(struct bio *, struct page *, unsigned int, unsigned int);
Martin K. Petersene7258c12014-09-26 19:19:55 -0400705extern bool bio_integrity_enabled(struct bio *bio);
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200706extern int bio_integrity_prep(struct bio *);
707extern void bio_integrity_endio(struct bio *, int);
708extern void bio_integrity_advance(struct bio *, unsigned int);
709extern void bio_integrity_trim(struct bio *, unsigned int, unsigned int);
Kent Overstreet1e2a410f2012-09-06 15:34:56 -0700710extern int bio_integrity_clone(struct bio *, struct bio *, gfp_t);
Martin K. Petersen7878cba2009-06-26 15:37:49 +0200711extern int bioset_integrity_create(struct bio_set *, int);
712extern void bioset_integrity_free(struct bio_set *);
713extern void bio_integrity_init(void);
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200714
715#else /* CONFIG_BLK_DEV_INTEGRITY */
716
Martin K. Petersenc6115292014-09-26 19:20:08 -0400717static inline void *bio_integrity(struct bio *bio)
Martin K. Petersen6898e3b2012-01-13 08:15:33 +0100718{
Martin K. Petersenc6115292014-09-26 19:20:08 -0400719 return NULL;
Martin K. Petersen6898e3b2012-01-13 08:15:33 +0100720}
721
Martin K. Petersene7258c12014-09-26 19:19:55 -0400722static inline bool bio_integrity_enabled(struct bio *bio)
Martin K. Petersen6898e3b2012-01-13 08:15:33 +0100723{
Martin K. Petersene7258c12014-09-26 19:19:55 -0400724 return false;
Martin K. Petersen6898e3b2012-01-13 08:15:33 +0100725}
726
727static inline int bioset_integrity_create(struct bio_set *bs, int pool_size)
728{
729 return 0;
730}
731
732static inline void bioset_integrity_free (struct bio_set *bs)
733{
734 return;
735}
736
737static inline int bio_integrity_prep(struct bio *bio)
738{
739 return 0;
740}
741
Kent Overstreet1e2a410f2012-09-06 15:34:56 -0700742static inline void bio_integrity_free(struct bio *bio)
Martin K. Petersen6898e3b2012-01-13 08:15:33 +0100743{
744 return;
745}
746
Stephen Rothwell0c614e22011-11-16 09:21:48 +0100747static inline int bio_integrity_clone(struct bio *bio, struct bio *bio_src,
Kent Overstreet1e2a410f2012-09-06 15:34:56 -0700748 gfp_t gfp_mask)
Stephen Rothwell0c614e22011-11-16 09:21:48 +0100749{
750 return 0;
751}
Martin K. Petersen6898e3b2012-01-13 08:15:33 +0100752
Martin K. Petersen6898e3b2012-01-13 08:15:33 +0100753static inline void bio_integrity_advance(struct bio *bio,
754 unsigned int bytes_done)
755{
756 return;
757}
758
759static inline void bio_integrity_trim(struct bio *bio, unsigned int offset,
760 unsigned int sectors)
761{
762 return;
763}
764
765static inline void bio_integrity_init(void)
766{
767 return;
768}
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200769
Martin K. Petersenc6115292014-09-26 19:20:08 -0400770static inline bool bio_integrity_flagged(struct bio *bio, enum bip_flags flag)
771{
772 return false;
773}
774
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200775#endif /* CONFIG_BLK_DEV_INTEGRITY */
776
David Howells02a5e0a2007-08-11 22:34:32 +0200777#endif /* CONFIG_BLOCK */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700778#endif /* __LINUX_BIO_H */