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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
Linus Torvalds1da177e2005-04-16 15:20:36 -0700198/*
Kent Overstreetd74c6d52013-02-06 12:23:11 -0800199 * drivers should _never_ use the all version - the bio may have been split
200 * before it got to the driver and the driver won't own all of it
201 */
202#define bio_for_each_segment_all(bvl, bio, i) \
Kent Overstreetf619d252013-08-07 14:30:33 -0700203 for (i = 0, bvl = (bio)->bi_io_vec; i < (bio)->bi_vcnt; i++, bvl++)
Kent Overstreetd74c6d52013-02-06 12:23:11 -0800204
Kent Overstreet4550dd62013-08-07 14:26:21 -0700205static inline void bvec_iter_advance(struct bio_vec *bv, struct bvec_iter *iter,
206 unsigned bytes)
207{
208 WARN_ONCE(bytes > iter->bi_size,
209 "Attempted to advance past end of bvec iter\n");
210
211 while (bytes) {
212 unsigned len = min(bytes, bvec_iter_len(bv, *iter));
213
214 bytes -= len;
215 iter->bi_size -= len;
216 iter->bi_bvec_done += len;
217
218 if (iter->bi_bvec_done == __bvec_iter_bvec(bv, *iter)->bv_len) {
219 iter->bi_bvec_done = 0;
220 iter->bi_idx++;
221 }
222 }
223}
224
225#define for_each_bvec(bvl, bio_vec, iter, start) \
Martin K. Petersenb7aa84d2014-04-08 22:43:43 -0400226 for (iter = (start); \
227 (iter).bi_size && \
228 ((bvl = bvec_iter_bvec((bio_vec), (iter))), 1); \
Kent Overstreet4550dd62013-08-07 14:26:21 -0700229 bvec_iter_advance((bio_vec), &(iter), (bvl).bv_len))
230
231
232static inline void bio_advance_iter(struct bio *bio, struct bvec_iter *iter,
233 unsigned bytes)
234{
235 iter->bi_sector += bytes >> 9;
236
237 if (bio->bi_rw & BIO_NO_ADVANCE_ITER_MASK)
238 iter->bi_size -= bytes;
239 else
240 bvec_iter_advance(bio->bi_io_vec, iter, bytes);
241}
242
Kent Overstreet79886132013-11-23 17:19:00 -0800243#define __bio_for_each_segment(bvl, bio, iter, start) \
244 for (iter = (start); \
Kent Overstreet4550dd62013-08-07 14:26:21 -0700245 (iter).bi_size && \
246 ((bvl = bio_iter_iovec((bio), (iter))), 1); \
247 bio_advance_iter((bio), &(iter), (bvl).bv_len))
Kent Overstreet79886132013-11-23 17:19:00 -0800248
249#define bio_for_each_segment(bvl, bio, iter) \
250 __bio_for_each_segment(bvl, bio, iter, (bio)->bi_iter)
251
Kent Overstreet4550dd62013-08-07 14:26:21 -0700252#define bio_iter_last(bvec, iter) ((iter).bi_size == (bvec).bv_len)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700253
Kent Overstreet458b76e2013-09-24 16:26:05 -0700254static inline unsigned bio_segments(struct bio *bio)
255{
256 unsigned segs = 0;
257 struct bio_vec bv;
258 struct bvec_iter iter;
259
Kent Overstreet8423ae32014-02-10 17:45:50 -0800260 /*
261 * We special case discard/write same, because they interpret bi_size
262 * differently:
263 */
264
265 if (bio->bi_rw & REQ_DISCARD)
266 return 1;
267
268 if (bio->bi_rw & REQ_WRITE_SAME)
269 return 1;
270
Kent Overstreet458b76e2013-09-24 16:26:05 -0700271 bio_for_each_segment(bv, bio, iter)
272 segs++;
273
274 return segs;
275}
276
Linus Torvalds1da177e2005-04-16 15:20:36 -0700277/*
278 * get a reference to a bio, so it won't disappear. the intended use is
279 * something like:
280 *
281 * bio_get(bio);
282 * submit_bio(rw, bio);
283 * if (bio->bi_flags ...)
284 * do_something
285 * bio_put(bio);
286 *
287 * without the bio_get(), it could potentially complete I/O before submit_bio
288 * returns. and then bio would be freed memory when if (bio->bi_flags ...)
289 * runs
290 */
Jens Axboedac56212015-04-17 16:23:59 -0600291static inline void bio_get(struct bio *bio)
292{
293 bio->bi_flags |= (1 << BIO_REFFED);
294 smp_mb__before_atomic();
295 atomic_inc(&bio->__bi_cnt);
296}
297
298static inline void bio_cnt_set(struct bio *bio, unsigned int count)
299{
300 if (count != 1) {
301 bio->bi_flags |= (1 << BIO_REFFED);
302 smp_mb__before_atomic();
303 }
304 atomic_set(&bio->__bi_cnt, count);
305}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700306
Jens Axboeb7c44ed2015-07-24 12:37:59 -0600307static inline bool bio_flagged(struct bio *bio, unsigned int bit)
308{
Jens Axboe2c68f6d2015-07-28 13:14:32 -0600309 return (bio->bi_flags & (1U << bit)) != 0;
Jens Axboeb7c44ed2015-07-24 12:37:59 -0600310}
311
312static inline void bio_set_flag(struct bio *bio, unsigned int bit)
313{
Jens Axboe2c68f6d2015-07-28 13:14:32 -0600314 bio->bi_flags |= (1U << bit);
Jens Axboeb7c44ed2015-07-24 12:37:59 -0600315}
316
317static inline void bio_clear_flag(struct bio *bio, unsigned int bit)
318{
Jens Axboe2c68f6d2015-07-28 13:14:32 -0600319 bio->bi_flags &= ~(1U << bit);
Jens Axboeb7c44ed2015-07-24 12:37:59 -0600320}
321
Martin K. Petersenc6115292014-09-26 19:20:08 -0400322enum bip_flags {
323 BIP_BLOCK_INTEGRITY = 1 << 0, /* block layer owns integrity data */
324 BIP_MAPPED_INTEGRITY = 1 << 1, /* ref tag has been remapped */
325 BIP_CTRL_NOCHECK = 1 << 2, /* disable HBA integrity checking */
326 BIP_DISK_NOCHECK = 1 << 3, /* disable disk integrity checking */
327 BIP_IP_CHECKSUM = 1 << 4, /* IP checksum */
328};
329
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200330#if defined(CONFIG_BLK_DEV_INTEGRITY)
Martin K. Petersen180b2f92014-09-26 19:19:56 -0400331
332static inline struct bio_integrity_payload *bio_integrity(struct bio *bio)
333{
334 if (bio->bi_rw & REQ_INTEGRITY)
335 return bio->bi_integrity;
336
337 return NULL;
338}
339
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200340/*
341 * bio integrity payload
342 */
343struct bio_integrity_payload {
344 struct bio *bip_bio; /* parent bio */
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200345
Kent Overstreetd57a5f72013-11-23 17:20:16 -0800346 struct bvec_iter bip_iter;
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200347
Kent Overstreetd57a5f72013-11-23 17:20:16 -0800348 bio_end_io_t *bip_end_io; /* saved I/O completion fn */
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200349
Martin K. Petersen7878cba2009-06-26 15:37:49 +0200350 unsigned short bip_slab; /* slab the bip came from */
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200351 unsigned short bip_vcnt; /* # of integrity bio_vecs */
Gu Zhengcbcd10542014-07-01 10:36:47 -0600352 unsigned short bip_max_vcnt; /* integrity bio_vec slots */
Martin K. Petersenb1f0138852014-09-26 19:20:04 -0400353 unsigned short bip_flags; /* control flags */
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200354
355 struct work_struct bip_work; /* I/O completion */
Kent Overstreet6fda9812012-10-12 13:18:27 -0700356
357 struct bio_vec *bip_vec;
358 struct bio_vec bip_inline_vecs[0];/* embedded bvec array */
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200359};
Martin K. Petersen18593082014-09-26 19:20:01 -0400360
Martin K. Petersenc6115292014-09-26 19:20:08 -0400361static inline bool bio_integrity_flagged(struct bio *bio, enum bip_flags flag)
362{
363 struct bio_integrity_payload *bip = bio_integrity(bio);
364
365 if (bip)
366 return bip->bip_flags & flag;
367
368 return false;
369}
Martin K. Petersenb1f0138852014-09-26 19:20:04 -0400370
Martin K. Petersen18593082014-09-26 19:20:01 -0400371static inline sector_t bip_get_seed(struct bio_integrity_payload *bip)
372{
373 return bip->bip_iter.bi_sector;
374}
375
376static inline void bip_set_seed(struct bio_integrity_payload *bip,
377 sector_t seed)
378{
379 bip->bip_iter.bi_sector = seed;
380}
381
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200382#endif /* CONFIG_BLK_DEV_INTEGRITY */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700383
Kent Overstreet6678d832013-08-07 11:14:32 -0700384extern void bio_trim(struct bio *bio, int offset, int size);
Kent Overstreet20d01892013-11-23 18:21:01 -0800385extern struct bio *bio_split(struct bio *bio, int sectors,
386 gfp_t gfp, struct bio_set *bs);
387
388/**
389 * bio_next_split - get next @sectors from a bio, splitting if necessary
390 * @bio: bio to split
391 * @sectors: number of sectors to split from the front of @bio
392 * @gfp: gfp mask
393 * @bs: bio set to allocate from
394 *
395 * Returns a bio representing the next @sectors of @bio - if the bio is smaller
396 * than @sectors, returns the original bio unchanged.
397 */
398static inline struct bio *bio_next_split(struct bio *bio, int sectors,
399 gfp_t gfp, struct bio_set *bs)
400{
401 if (sectors >= bio_sectors(bio))
402 return bio;
403
404 return bio_split(bio, sectors, gfp, bs);
405}
406
Jens Axboebb799ca2008-12-10 15:35:05 +0100407extern struct bio_set *bioset_create(unsigned int, unsigned int);
Junichi Nomurad8f429e2014-10-03 17:27:12 -0400408extern struct bio_set *bioset_create_nobvec(unsigned int, unsigned int);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700409extern void bioset_free(struct bio_set *);
Fabian Fredericka6c39cb4f2014-04-22 15:09:05 -0600410extern mempool_t *biovec_create_pool(int pool_entries);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700411
Al Virodd0fc662005-10-07 07:46:04 +0100412extern struct bio *bio_alloc_bioset(gfp_t, int, struct bio_set *);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700413extern void bio_put(struct bio *);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700414
Kent Overstreet59d276f2013-11-23 18:19:27 -0800415extern void __bio_clone_fast(struct bio *, struct bio *);
416extern struct bio *bio_clone_fast(struct bio *, gfp_t, struct bio_set *);
Kent Overstreetbf800ef2012-09-06 15:35:02 -0700417extern struct bio *bio_clone_bioset(struct bio *, gfp_t, struct bio_set *bs);
418
Kent Overstreet3f86a822012-09-06 15:35:01 -0700419extern struct bio_set *fs_bio_set;
420
421static inline struct bio *bio_alloc(gfp_t gfp_mask, unsigned int nr_iovecs)
422{
423 return bio_alloc_bioset(gfp_mask, nr_iovecs, fs_bio_set);
424}
425
Kent Overstreetbf800ef2012-09-06 15:35:02 -0700426static inline struct bio *bio_clone(struct bio *bio, gfp_t gfp_mask)
427{
428 return bio_clone_bioset(bio, gfp_mask, fs_bio_set);
429}
430
Kent Overstreet3f86a822012-09-06 15:35:01 -0700431static inline struct bio *bio_kmalloc(gfp_t gfp_mask, unsigned int nr_iovecs)
432{
433 return bio_alloc_bioset(gfp_mask, nr_iovecs, NULL);
434}
435
Kent Overstreetbf800ef2012-09-06 15:35:02 -0700436static inline struct bio *bio_clone_kmalloc(struct bio *bio, gfp_t gfp_mask)
437{
438 return bio_clone_bioset(bio, gfp_mask, NULL);
439
440}
441
Christoph Hellwig4246a0b2015-07-20 15:29:37 +0200442extern void bio_endio(struct bio *);
443
444static inline void bio_io_error(struct bio *bio)
445{
446 bio->bi_error = -EIO;
447 bio_endio(bio);
448}
449
Linus Torvalds1da177e2005-04-16 15:20:36 -0700450struct request_queue;
451extern int bio_phys_segments(struct request_queue *, struct bio *);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700452
Kent Overstreet9e882242012-09-10 14:41:12 -0700453extern int submit_bio_wait(int rw, struct bio *bio);
Kent Overstreet054bdf62012-09-28 13:17:55 -0700454extern void bio_advance(struct bio *, unsigned);
455
Linus Torvalds1da177e2005-04-16 15:20:36 -0700456extern void bio_init(struct bio *);
Kent Overstreetf44b48c2012-09-06 15:34:58 -0700457extern void bio_reset(struct bio *);
Kent Overstreet196d38b2013-11-23 18:34:15 -0800458void bio_chain(struct bio *, struct bio *);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700459
460extern int bio_add_page(struct bio *, struct page *, unsigned int,unsigned int);
Mike Christie6e68af62005-11-11 05:30:27 -0600461extern int bio_add_pc_page(struct request_queue *, struct bio *, struct page *,
462 unsigned int, unsigned int);
FUJITA Tomonori152e2832008-08-28 16:17:06 +0900463struct rq_map_data;
James Bottomley f1970ba2005-06-20 14:06:52 +0200464extern struct bio *bio_map_user_iov(struct request_queue *,
Kent Overstreet26e49cf2015-01-18 16:16:31 +0100465 const struct iov_iter *, gfp_t);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700466extern void bio_unmap_user(struct bio *);
Mike Christie df46b9a2005-06-20 14:04:44 +0200467extern struct bio *bio_map_kern(struct request_queue *, void *, unsigned int,
Al Viro27496a82005-10-21 03:20:48 -0400468 gfp_t);
FUJITA Tomonori68154e92008-04-25 12:47:50 +0200469extern struct bio *bio_copy_kern(struct request_queue *, void *, unsigned int,
470 gfp_t, int);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700471extern void bio_set_pages_dirty(struct bio *bio);
472extern void bio_check_pages_dirty(struct bio *bio);
Ilya Loginov2d4dc892009-11-26 09:16:19 +0100473
Gu Zheng394ffa52014-11-24 11:05:22 +0800474void generic_start_io_acct(int rw, unsigned long sectors,
475 struct hd_struct *part);
476void generic_end_io_acct(int rw, struct hd_struct *part,
477 unsigned long start_time);
478
Ilya Loginov2d4dc892009-11-26 09:16:19 +0100479#ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
480# error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform"
481#endif
482#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
483extern void bio_flush_dcache_pages(struct bio *bi);
484#else
485static inline void bio_flush_dcache_pages(struct bio *bi)
486{
487}
488#endif
489
Kent Overstreet16ac3d62012-09-10 13:57:51 -0700490extern void bio_copy_data(struct bio *dst, struct bio *src);
Kent Overstreeta0787602012-09-10 14:03:28 -0700491extern int bio_alloc_pages(struct bio *bio, gfp_t gfp);
Kent Overstreet16ac3d62012-09-10 13:57:51 -0700492
FUJITA Tomonori152e2832008-08-28 16:17:06 +0900493extern struct bio *bio_copy_user_iov(struct request_queue *,
Al Viro86d564c2014-02-08 20:42:52 -0500494 struct rq_map_data *,
Kent Overstreet26e49cf2015-01-18 16:16:31 +0100495 const struct iov_iter *,
496 gfp_t);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700497extern int bio_uncopy_user(struct bio *);
498void zero_fill_bio(struct bio *bio);
Kent Overstreet9f060e22012-10-12 15:29:33 -0700499extern struct bio_vec *bvec_alloc(gfp_t, int, unsigned long *, mempool_t *);
500extern void bvec_free(mempool_t *, struct bio_vec *, unsigned int);
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200501extern unsigned int bvec_nr_vecs(unsigned short idx);
Martin K. Petersen51d654e2008-06-17 18:59:56 +0200502
Tejun Heo852c7882012-03-05 13:15:27 -0800503#ifdef CONFIG_BLK_CGROUP
Tejun Heo1d933cf2015-05-22 17:13:24 -0400504int bio_associate_blkcg(struct bio *bio, struct cgroup_subsys_state *blkcg_css);
Tejun Heo852c7882012-03-05 13:15:27 -0800505int bio_associate_current(struct bio *bio);
506void bio_disassociate_task(struct bio *bio);
507#else /* CONFIG_BLK_CGROUP */
Tejun Heo1d933cf2015-05-22 17:13:24 -0400508static inline int bio_associate_blkcg(struct bio *bio,
509 struct cgroup_subsys_state *blkcg_css) { return 0; }
Tejun Heo852c7882012-03-05 13:15:27 -0800510static inline int bio_associate_current(struct bio *bio) { return -ENOENT; }
511static inline void bio_disassociate_task(struct bio *bio) { }
512#endif /* CONFIG_BLK_CGROUP */
513
Linus Torvalds1da177e2005-04-16 15:20:36 -0700514#ifdef CONFIG_HIGHMEM
515/*
Alberto Bertogli20b636b2009-02-02 12:41:07 +0100516 * remember never ever reenable interrupts between a bvec_kmap_irq and
517 * bvec_kunmap_irq!
Linus Torvalds1da177e2005-04-16 15:20:36 -0700518 */
Alberto Bertogli4f570f92009-11-02 11:40:16 +0100519static inline char *bvec_kmap_irq(struct bio_vec *bvec, unsigned long *flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700520{
521 unsigned long addr;
522
523 /*
524 * might not be a highmem page, but the preempt/irq count
525 * balancing is a lot nicer this way
526 */
527 local_irq_save(*flags);
Cong Wange8e3c3d2011-11-25 23:14:27 +0800528 addr = (unsigned long) kmap_atomic(bvec->bv_page);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700529
530 BUG_ON(addr & ~PAGE_MASK);
531
532 return (char *) addr + bvec->bv_offset;
533}
534
Alberto Bertogli4f570f92009-11-02 11:40:16 +0100535static inline void bvec_kunmap_irq(char *buffer, unsigned long *flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700536{
537 unsigned long ptr = (unsigned long) buffer & PAGE_MASK;
538
Cong Wange8e3c3d2011-11-25 23:14:27 +0800539 kunmap_atomic((void *) ptr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700540 local_irq_restore(*flags);
541}
542
543#else
Geert Uytterhoeven11a691b2010-10-21 10:32:29 +0200544static inline char *bvec_kmap_irq(struct bio_vec *bvec, unsigned long *flags)
545{
546 return page_address(bvec->bv_page) + bvec->bv_offset;
547}
548
549static inline void bvec_kunmap_irq(char *buffer, unsigned long *flags)
550{
551 *flags = 0;
552}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700553#endif
554
Kent Overstreetf619d252013-08-07 14:30:33 -0700555static inline char *__bio_kmap_irq(struct bio *bio, struct bvec_iter iter,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700556 unsigned long *flags)
557{
Kent Overstreetf619d252013-08-07 14:30:33 -0700558 return bvec_kmap_irq(&bio_iter_iovec(bio, iter), flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700559}
560#define __bio_kunmap_irq(buf, flags) bvec_kunmap_irq(buf, flags)
561
562#define bio_kmap_irq(bio, flags) \
Kent Overstreetf619d252013-08-07 14:30:33 -0700563 __bio_kmap_irq((bio), (bio)->bi_iter, (flags))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700564#define bio_kunmap_irq(buf,flags) __bio_kunmap_irq(buf, flags)
565
Jens Axboe7a67f632008-08-08 11:17:12 +0200566/*
Akinobu Mitae6863072009-04-17 08:41:21 +0200567 * BIO list management for use by remapping drivers (e.g. DM or MD) and loop.
Christoph Hellwig8f3d8ba2009-04-07 19:55:13 +0200568 *
569 * A bio_list anchors a singly-linked list of bios chained through the bi_next
570 * member of the bio. The bio_list also caches the last list member to allow
571 * fast access to the tail.
572 */
573struct bio_list {
574 struct bio *head;
575 struct bio *tail;
576};
577
578static inline int bio_list_empty(const struct bio_list *bl)
579{
580 return bl->head == NULL;
581}
582
583static inline void bio_list_init(struct bio_list *bl)
584{
585 bl->head = bl->tail = NULL;
586}
587
Jens Axboe320ae512013-10-24 09:20:05 +0100588#define BIO_EMPTY_LIST { NULL, NULL }
589
Christoph Hellwig8f3d8ba2009-04-07 19:55:13 +0200590#define bio_list_for_each(bio, bl) \
591 for (bio = (bl)->head; bio; bio = bio->bi_next)
592
593static inline unsigned bio_list_size(const struct bio_list *bl)
594{
595 unsigned sz = 0;
596 struct bio *bio;
597
598 bio_list_for_each(bio, bl)
599 sz++;
600
601 return sz;
602}
603
604static inline void bio_list_add(struct bio_list *bl, struct bio *bio)
605{
606 bio->bi_next = NULL;
607
608 if (bl->tail)
609 bl->tail->bi_next = bio;
610 else
611 bl->head = bio;
612
613 bl->tail = bio;
614}
615
616static inline void bio_list_add_head(struct bio_list *bl, struct bio *bio)
617{
618 bio->bi_next = bl->head;
619
620 bl->head = bio;
621
622 if (!bl->tail)
623 bl->tail = bio;
624}
625
626static inline void bio_list_merge(struct bio_list *bl, struct bio_list *bl2)
627{
628 if (!bl2->head)
629 return;
630
631 if (bl->tail)
632 bl->tail->bi_next = bl2->head;
633 else
634 bl->head = bl2->head;
635
636 bl->tail = bl2->tail;
637}
638
639static inline void bio_list_merge_head(struct bio_list *bl,
640 struct bio_list *bl2)
641{
642 if (!bl2->head)
643 return;
644
645 if (bl->head)
646 bl2->tail->bi_next = bl->head;
647 else
648 bl->tail = bl2->tail;
649
650 bl->head = bl2->head;
651}
652
Geert Uytterhoeven13685a12009-06-10 04:38:40 +0000653static inline struct bio *bio_list_peek(struct bio_list *bl)
654{
655 return bl->head;
656}
657
Christoph Hellwig8f3d8ba2009-04-07 19:55:13 +0200658static inline struct bio *bio_list_pop(struct bio_list *bl)
659{
660 struct bio *bio = bl->head;
661
662 if (bio) {
663 bl->head = bl->head->bi_next;
664 if (!bl->head)
665 bl->tail = NULL;
666
667 bio->bi_next = NULL;
668 }
669
670 return bio;
671}
672
673static inline struct bio *bio_list_get(struct bio_list *bl)
674{
675 struct bio *bio = bl->head;
676
677 bl->head = bl->tail = NULL;
678
679 return bio;
680}
681
Kent Overstreet57fb2332012-08-24 04:56:11 -0700682/*
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[].
687 */
688#define BIO_POOL_SIZE 2
689#define BIOVEC_NR_POOLS 6
690#define BIOVEC_MAX_IDX (BIOVEC_NR_POOLS - 1)
691
692struct bio_set {
693 struct kmem_cache *bio_slab;
694 unsigned int front_pad;
695
696 mempool_t *bio_pool;
Kent Overstreet9f060e22012-10-12 15:29:33 -0700697 mempool_t *bvec_pool;
Kent Overstreet57fb2332012-08-24 04:56:11 -0700698#if defined(CONFIG_BLK_DEV_INTEGRITY)
699 mempool_t *bio_integrity_pool;
Kent Overstreet9f060e22012-10-12 15:29:33 -0700700 mempool_t *bvec_integrity_pool;
Kent Overstreet57fb2332012-08-24 04:56:11 -0700701#endif
Kent Overstreetdf2cb6d2012-09-10 14:33:46 -0700702
703 /*
704 * Deadlock avoidance for stacking block drivers: see comments in
705 * bio_alloc_bioset() for details
706 */
707 spinlock_t rescue_lock;
708 struct bio_list rescue_list;
709 struct work_struct rescue_work;
710 struct workqueue_struct *rescue_workqueue;
Kent Overstreet57fb2332012-08-24 04:56:11 -0700711};
712
713struct biovec_slab {
714 int nr_vecs;
715 char *name;
716 struct kmem_cache *slab;
717};
718
719/*
720 * a small number of entries is fine, not going to be performance critical.
721 * basically we just need to survive
722 */
723#define BIO_SPLIT_ENTRIES 2
724
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200725#if defined(CONFIG_BLK_DEV_INTEGRITY)
726
Kent Overstreetd57a5f72013-11-23 17:20:16 -0800727#define bip_for_each_vec(bvl, bip, iter) \
728 for_each_bvec(bvl, (bip)->bip_vec, iter, (bip)->bip_iter)
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200729
Martin K. Petersen13f05c82010-09-10 20:50:10 +0200730#define bio_for_each_integrity_vec(_bvl, _bio, _iter) \
731 for_each_bio(_bio) \
732 bip_for_each_vec(_bvl, _bio->bi_integrity, _iter)
733
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200734extern struct bio_integrity_payload *bio_integrity_alloc(struct bio *, gfp_t, unsigned int);
Kent Overstreet1e2a410f2012-09-06 15:34:56 -0700735extern void bio_integrity_free(struct bio *);
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200736extern int bio_integrity_add_page(struct bio *, struct page *, unsigned int, unsigned int);
Martin K. Petersene7258c12014-09-26 19:19:55 -0400737extern bool bio_integrity_enabled(struct bio *bio);
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200738extern int bio_integrity_prep(struct bio *);
Christoph Hellwig4246a0b2015-07-20 15:29:37 +0200739extern void bio_integrity_endio(struct bio *);
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200740extern void bio_integrity_advance(struct bio *, unsigned int);
741extern void bio_integrity_trim(struct bio *, unsigned int, unsigned int);
Kent Overstreet1e2a410f2012-09-06 15:34:56 -0700742extern int bio_integrity_clone(struct bio *, struct bio *, gfp_t);
Martin K. Petersen7878cba2009-06-26 15:37:49 +0200743extern int bioset_integrity_create(struct bio_set *, int);
744extern void bioset_integrity_free(struct bio_set *);
745extern void bio_integrity_init(void);
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200746
747#else /* CONFIG_BLK_DEV_INTEGRITY */
748
Martin K. Petersenc6115292014-09-26 19:20:08 -0400749static inline void *bio_integrity(struct bio *bio)
Martin K. Petersen6898e3b2012-01-13 08:15:33 +0100750{
Martin K. Petersenc6115292014-09-26 19:20:08 -0400751 return NULL;
Martin K. Petersen6898e3b2012-01-13 08:15:33 +0100752}
753
Martin K. Petersene7258c12014-09-26 19:19:55 -0400754static inline bool bio_integrity_enabled(struct bio *bio)
Martin K. Petersen6898e3b2012-01-13 08:15:33 +0100755{
Martin K. Petersene7258c12014-09-26 19:19:55 -0400756 return false;
Martin K. Petersen6898e3b2012-01-13 08:15:33 +0100757}
758
759static inline int bioset_integrity_create(struct bio_set *bs, int pool_size)
760{
761 return 0;
762}
763
764static inline void bioset_integrity_free (struct bio_set *bs)
765{
766 return;
767}
768
769static inline int bio_integrity_prep(struct bio *bio)
770{
771 return 0;
772}
773
Kent Overstreet1e2a410f2012-09-06 15:34:56 -0700774static inline void bio_integrity_free(struct bio *bio)
Martin K. Petersen6898e3b2012-01-13 08:15:33 +0100775{
776 return;
777}
778
Stephen Rothwell0c614e22011-11-16 09:21:48 +0100779static inline int bio_integrity_clone(struct bio *bio, struct bio *bio_src,
Kent Overstreet1e2a410f2012-09-06 15:34:56 -0700780 gfp_t gfp_mask)
Stephen Rothwell0c614e22011-11-16 09:21:48 +0100781{
782 return 0;
783}
Martin K. Petersen6898e3b2012-01-13 08:15:33 +0100784
Martin K. Petersen6898e3b2012-01-13 08:15:33 +0100785static inline void bio_integrity_advance(struct bio *bio,
786 unsigned int bytes_done)
787{
788 return;
789}
790
791static inline void bio_integrity_trim(struct bio *bio, unsigned int offset,
792 unsigned int sectors)
793{
794 return;
795}
796
797static inline void bio_integrity_init(void)
798{
799 return;
800}
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200801
Martin K. Petersenc6115292014-09-26 19:20:08 -0400802static inline bool bio_integrity_flagged(struct bio *bio, enum bip_flags flag)
803{
804 return false;
805}
806
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200807#endif /* CONFIG_BLK_DEV_INTEGRITY */
808
David Howells02a5e0a2007-08-11 22:34:32 +0200809#endif /* CONFIG_BLOCK */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700810#endif /* __LINUX_BIO_H */