blob: 6b918177002d696adedf1ce813a1367ce013a4af [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
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
Martin K. Petersenc6115292014-09-26 19:20:08 -0400307enum bip_flags {
308 BIP_BLOCK_INTEGRITY = 1 << 0, /* block layer owns integrity data */
309 BIP_MAPPED_INTEGRITY = 1 << 1, /* ref tag has been remapped */
310 BIP_CTRL_NOCHECK = 1 << 2, /* disable HBA integrity checking */
311 BIP_DISK_NOCHECK = 1 << 3, /* disable disk integrity checking */
312 BIP_IP_CHECKSUM = 1 << 4, /* IP checksum */
313};
314
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200315#if defined(CONFIG_BLK_DEV_INTEGRITY)
Martin K. Petersen180b2f92014-09-26 19:19:56 -0400316
317static inline struct bio_integrity_payload *bio_integrity(struct bio *bio)
318{
319 if (bio->bi_rw & REQ_INTEGRITY)
320 return bio->bi_integrity;
321
322 return NULL;
323}
324
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200325/*
326 * bio integrity payload
327 */
328struct bio_integrity_payload {
329 struct bio *bip_bio; /* parent bio */
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200330
Kent Overstreetd57a5f72013-11-23 17:20:16 -0800331 struct bvec_iter bip_iter;
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200332
Kent Overstreetd57a5f72013-11-23 17:20:16 -0800333 bio_end_io_t *bip_end_io; /* saved I/O completion fn */
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200334
Martin K. Petersen7878cba2009-06-26 15:37:49 +0200335 unsigned short bip_slab; /* slab the bip came from */
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200336 unsigned short bip_vcnt; /* # of integrity bio_vecs */
Gu Zhengcbcd10542014-07-01 10:36:47 -0600337 unsigned short bip_max_vcnt; /* integrity bio_vec slots */
Martin K. Petersenb1f0138852014-09-26 19:20:04 -0400338 unsigned short bip_flags; /* control flags */
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200339
340 struct work_struct bip_work; /* I/O completion */
Kent Overstreet6fda9812012-10-12 13:18:27 -0700341
342 struct bio_vec *bip_vec;
343 struct bio_vec bip_inline_vecs[0];/* embedded bvec array */
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200344};
Martin K. Petersen18593082014-09-26 19:20:01 -0400345
Martin K. Petersenc6115292014-09-26 19:20:08 -0400346static inline bool bio_integrity_flagged(struct bio *bio, enum bip_flags flag)
347{
348 struct bio_integrity_payload *bip = bio_integrity(bio);
349
350 if (bip)
351 return bip->bip_flags & flag;
352
353 return false;
354}
Martin K. Petersenb1f0138852014-09-26 19:20:04 -0400355
Martin K. Petersen18593082014-09-26 19:20:01 -0400356static inline sector_t bip_get_seed(struct bio_integrity_payload *bip)
357{
358 return bip->bip_iter.bi_sector;
359}
360
361static inline void bip_set_seed(struct bio_integrity_payload *bip,
362 sector_t seed)
363{
364 bip->bip_iter.bi_sector = seed;
365}
366
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200367#endif /* CONFIG_BLK_DEV_INTEGRITY */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700368
Kent Overstreet6678d832013-08-07 11:14:32 -0700369extern void bio_trim(struct bio *bio, int offset, int size);
Kent Overstreet20d01892013-11-23 18:21:01 -0800370extern struct bio *bio_split(struct bio *bio, int sectors,
371 gfp_t gfp, struct bio_set *bs);
372
373/**
374 * bio_next_split - get next @sectors from a bio, splitting if necessary
375 * @bio: bio to split
376 * @sectors: number of sectors to split from the front of @bio
377 * @gfp: gfp mask
378 * @bs: bio set to allocate from
379 *
380 * Returns a bio representing the next @sectors of @bio - if the bio is smaller
381 * than @sectors, returns the original bio unchanged.
382 */
383static inline struct bio *bio_next_split(struct bio *bio, int sectors,
384 gfp_t gfp, struct bio_set *bs)
385{
386 if (sectors >= bio_sectors(bio))
387 return bio;
388
389 return bio_split(bio, sectors, gfp, bs);
390}
391
Jens Axboebb799ca2008-12-10 15:35:05 +0100392extern struct bio_set *bioset_create(unsigned int, unsigned int);
Junichi Nomurad8f429e2014-10-03 17:27:12 -0400393extern struct bio_set *bioset_create_nobvec(unsigned int, unsigned int);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700394extern void bioset_free(struct bio_set *);
Fabian Fredericka6c39cb4f2014-04-22 15:09:05 -0600395extern mempool_t *biovec_create_pool(int pool_entries);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700396
Al Virodd0fc662005-10-07 07:46:04 +0100397extern struct bio *bio_alloc_bioset(gfp_t, int, struct bio_set *);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700398extern void bio_put(struct bio *);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700399
Kent Overstreet59d276f2013-11-23 18:19:27 -0800400extern void __bio_clone_fast(struct bio *, struct bio *);
401extern struct bio *bio_clone_fast(struct bio *, gfp_t, struct bio_set *);
Kent Overstreetbf800ef2012-09-06 15:35:02 -0700402extern struct bio *bio_clone_bioset(struct bio *, gfp_t, struct bio_set *bs);
403
Kent Overstreet3f86a822012-09-06 15:35:01 -0700404extern struct bio_set *fs_bio_set;
405
406static inline struct bio *bio_alloc(gfp_t gfp_mask, unsigned int nr_iovecs)
407{
408 return bio_alloc_bioset(gfp_mask, nr_iovecs, fs_bio_set);
409}
410
Kent Overstreetbf800ef2012-09-06 15:35:02 -0700411static inline struct bio *bio_clone(struct bio *bio, gfp_t gfp_mask)
412{
413 return bio_clone_bioset(bio, gfp_mask, fs_bio_set);
414}
415
Kent Overstreet3f86a822012-09-06 15:35:01 -0700416static inline struct bio *bio_kmalloc(gfp_t gfp_mask, unsigned int nr_iovecs)
417{
418 return bio_alloc_bioset(gfp_mask, nr_iovecs, NULL);
419}
420
Kent Overstreetbf800ef2012-09-06 15:35:02 -0700421static inline struct bio *bio_clone_kmalloc(struct bio *bio, gfp_t gfp_mask)
422{
423 return bio_clone_bioset(bio, gfp_mask, NULL);
424
425}
426
Christoph Hellwig4246a0b2015-07-20 15:29:37 +0200427extern void bio_endio(struct bio *);
428
429static inline void bio_io_error(struct bio *bio)
430{
431 bio->bi_error = -EIO;
432 bio_endio(bio);
433}
434
Linus Torvalds1da177e2005-04-16 15:20:36 -0700435struct request_queue;
436extern int bio_phys_segments(struct request_queue *, struct bio *);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700437
Kent Overstreet9e882242012-09-10 14:41:12 -0700438extern int submit_bio_wait(int rw, struct bio *bio);
Kent Overstreet054bdf62012-09-28 13:17:55 -0700439extern void bio_advance(struct bio *, unsigned);
440
Linus Torvalds1da177e2005-04-16 15:20:36 -0700441extern void bio_init(struct bio *);
Kent Overstreetf44b48c72012-09-06 15:34:58 -0700442extern void bio_reset(struct bio *);
Kent Overstreet196d38bc2013-11-23 18:34:15 -0800443void bio_chain(struct bio *, struct bio *);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700444
445extern int bio_add_page(struct bio *, struct page *, unsigned int,unsigned int);
Mike Christie6e68af62005-11-11 05:30:27 -0600446extern int bio_add_pc_page(struct request_queue *, struct bio *, struct page *,
447 unsigned int, unsigned int);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700448extern int bio_get_nr_vecs(struct block_device *);
FUJITA Tomonori152e2832008-08-28 16:17:06 +0900449struct rq_map_data;
James Bottomley f1970ba2005-06-20 14:06:52 +0200450extern struct bio *bio_map_user_iov(struct request_queue *,
Kent Overstreet26e49cf2015-01-18 16:16:31 +0100451 const struct iov_iter *, gfp_t);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700452extern void bio_unmap_user(struct bio *);
Mike Christie df46b9a2005-06-20 14:04:44 +0200453extern struct bio *bio_map_kern(struct request_queue *, void *, unsigned int,
Al Viro27496a82005-10-21 03:20:48 -0400454 gfp_t);
FUJITA Tomonori68154e92008-04-25 12:47:50 +0200455extern struct bio *bio_copy_kern(struct request_queue *, void *, unsigned int,
456 gfp_t, int);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700457extern void bio_set_pages_dirty(struct bio *bio);
458extern void bio_check_pages_dirty(struct bio *bio);
Ilya Loginov2d4dc892009-11-26 09:16:19 +0100459
Gu Zheng394ffa52014-11-24 11:05:22 +0800460void generic_start_io_acct(int rw, unsigned long sectors,
461 struct hd_struct *part);
462void generic_end_io_acct(int rw, struct hd_struct *part,
463 unsigned long start_time);
464
Ilya Loginov2d4dc892009-11-26 09:16:19 +0100465#ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
466# error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform"
467#endif
468#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
469extern void bio_flush_dcache_pages(struct bio *bi);
470#else
471static inline void bio_flush_dcache_pages(struct bio *bi)
472{
473}
474#endif
475
Kent Overstreet16ac3d62012-09-10 13:57:51 -0700476extern void bio_copy_data(struct bio *dst, struct bio *src);
Kent Overstreeta0787602012-09-10 14:03:28 -0700477extern int bio_alloc_pages(struct bio *bio, gfp_t gfp);
Kent Overstreet16ac3d62012-09-10 13:57:51 -0700478
FUJITA Tomonori152e2832008-08-28 16:17:06 +0900479extern struct bio *bio_copy_user_iov(struct request_queue *,
Al Viro86d564c2014-02-08 20:42:52 -0500480 struct rq_map_data *,
Kent Overstreet26e49cf2015-01-18 16:16:31 +0100481 const struct iov_iter *,
482 gfp_t);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700483extern int bio_uncopy_user(struct bio *);
484void zero_fill_bio(struct bio *bio);
Kent Overstreet9f060e22012-10-12 15:29:33 -0700485extern struct bio_vec *bvec_alloc(gfp_t, int, unsigned long *, mempool_t *);
486extern void bvec_free(mempool_t *, struct bio_vec *, unsigned int);
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200487extern unsigned int bvec_nr_vecs(unsigned short idx);
Martin K. Petersen51d654e2008-06-17 18:59:56 +0200488
Tejun Heo852c7882012-03-05 13:15:27 -0800489#ifdef CONFIG_BLK_CGROUP
Tejun Heo1d933cf2015-05-22 17:13:24 -0400490int bio_associate_blkcg(struct bio *bio, struct cgroup_subsys_state *blkcg_css);
Tejun Heo852c7882012-03-05 13:15:27 -0800491int bio_associate_current(struct bio *bio);
492void bio_disassociate_task(struct bio *bio);
493#else /* CONFIG_BLK_CGROUP */
Tejun Heo1d933cf2015-05-22 17:13:24 -0400494static inline int bio_associate_blkcg(struct bio *bio,
495 struct cgroup_subsys_state *blkcg_css) { return 0; }
Tejun Heo852c7882012-03-05 13:15:27 -0800496static inline int bio_associate_current(struct bio *bio) { return -ENOENT; }
497static inline void bio_disassociate_task(struct bio *bio) { }
498#endif /* CONFIG_BLK_CGROUP */
499
Linus Torvalds1da177e2005-04-16 15:20:36 -0700500#ifdef CONFIG_HIGHMEM
501/*
Alberto Bertogli20b636b2009-02-02 12:41:07 +0100502 * remember never ever reenable interrupts between a bvec_kmap_irq and
503 * bvec_kunmap_irq!
Linus Torvalds1da177e2005-04-16 15:20:36 -0700504 */
Alberto Bertogli4f570f92009-11-02 11:40:16 +0100505static inline char *bvec_kmap_irq(struct bio_vec *bvec, unsigned long *flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700506{
507 unsigned long addr;
508
509 /*
510 * might not be a highmem page, but the preempt/irq count
511 * balancing is a lot nicer this way
512 */
513 local_irq_save(*flags);
Cong Wange8e3c3d2011-11-25 23:14:27 +0800514 addr = (unsigned long) kmap_atomic(bvec->bv_page);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700515
516 BUG_ON(addr & ~PAGE_MASK);
517
518 return (char *) addr + bvec->bv_offset;
519}
520
Alberto Bertogli4f570f92009-11-02 11:40:16 +0100521static inline void bvec_kunmap_irq(char *buffer, unsigned long *flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700522{
523 unsigned long ptr = (unsigned long) buffer & PAGE_MASK;
524
Cong Wange8e3c3d2011-11-25 23:14:27 +0800525 kunmap_atomic((void *) ptr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700526 local_irq_restore(*flags);
527}
528
529#else
Geert Uytterhoeven11a691b2010-10-21 10:32:29 +0200530static inline char *bvec_kmap_irq(struct bio_vec *bvec, unsigned long *flags)
531{
532 return page_address(bvec->bv_page) + bvec->bv_offset;
533}
534
535static inline void bvec_kunmap_irq(char *buffer, unsigned long *flags)
536{
537 *flags = 0;
538}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700539#endif
540
Kent Overstreetf619d252013-08-07 14:30:33 -0700541static inline char *__bio_kmap_irq(struct bio *bio, struct bvec_iter iter,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700542 unsigned long *flags)
543{
Kent Overstreetf619d252013-08-07 14:30:33 -0700544 return bvec_kmap_irq(&bio_iter_iovec(bio, iter), flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700545}
546#define __bio_kunmap_irq(buf, flags) bvec_kunmap_irq(buf, flags)
547
548#define bio_kmap_irq(bio, flags) \
Kent Overstreetf619d252013-08-07 14:30:33 -0700549 __bio_kmap_irq((bio), (bio)->bi_iter, (flags))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700550#define bio_kunmap_irq(buf,flags) __bio_kunmap_irq(buf, flags)
551
Jens Axboe7a67f632008-08-08 11:17:12 +0200552/*
Akinobu Mitae6863072009-04-17 08:41:21 +0200553 * BIO list management for use by remapping drivers (e.g. DM or MD) and loop.
Christoph Hellwig8f3d8ba2009-04-07 19:55:13 +0200554 *
555 * A bio_list anchors a singly-linked list of bios chained through the bi_next
556 * member of the bio. The bio_list also caches the last list member to allow
557 * fast access to the tail.
558 */
559struct bio_list {
560 struct bio *head;
561 struct bio *tail;
562};
563
564static inline int bio_list_empty(const struct bio_list *bl)
565{
566 return bl->head == NULL;
567}
568
569static inline void bio_list_init(struct bio_list *bl)
570{
571 bl->head = bl->tail = NULL;
572}
573
Jens Axboe320ae512013-10-24 09:20:05 +0100574#define BIO_EMPTY_LIST { NULL, NULL }
575
Christoph Hellwig8f3d8ba2009-04-07 19:55:13 +0200576#define bio_list_for_each(bio, bl) \
577 for (bio = (bl)->head; bio; bio = bio->bi_next)
578
579static inline unsigned bio_list_size(const struct bio_list *bl)
580{
581 unsigned sz = 0;
582 struct bio *bio;
583
584 bio_list_for_each(bio, bl)
585 sz++;
586
587 return sz;
588}
589
590static inline void bio_list_add(struct bio_list *bl, struct bio *bio)
591{
592 bio->bi_next = NULL;
593
594 if (bl->tail)
595 bl->tail->bi_next = bio;
596 else
597 bl->head = bio;
598
599 bl->tail = bio;
600}
601
602static inline void bio_list_add_head(struct bio_list *bl, struct bio *bio)
603{
604 bio->bi_next = bl->head;
605
606 bl->head = bio;
607
608 if (!bl->tail)
609 bl->tail = bio;
610}
611
612static inline void bio_list_merge(struct bio_list *bl, struct bio_list *bl2)
613{
614 if (!bl2->head)
615 return;
616
617 if (bl->tail)
618 bl->tail->bi_next = bl2->head;
619 else
620 bl->head = bl2->head;
621
622 bl->tail = bl2->tail;
623}
624
625static inline void bio_list_merge_head(struct bio_list *bl,
626 struct bio_list *bl2)
627{
628 if (!bl2->head)
629 return;
630
631 if (bl->head)
632 bl2->tail->bi_next = bl->head;
633 else
634 bl->tail = bl2->tail;
635
636 bl->head = bl2->head;
637}
638
Geert Uytterhoeven13685a12009-06-10 04:38:40 +0000639static inline struct bio *bio_list_peek(struct bio_list *bl)
640{
641 return bl->head;
642}
643
Christoph Hellwig8f3d8ba2009-04-07 19:55:13 +0200644static inline struct bio *bio_list_pop(struct bio_list *bl)
645{
646 struct bio *bio = bl->head;
647
648 if (bio) {
649 bl->head = bl->head->bi_next;
650 if (!bl->head)
651 bl->tail = NULL;
652
653 bio->bi_next = NULL;
654 }
655
656 return bio;
657}
658
659static inline struct bio *bio_list_get(struct bio_list *bl)
660{
661 struct bio *bio = bl->head;
662
663 bl->head = bl->tail = NULL;
664
665 return bio;
666}
667
Kent Overstreet57fb2332012-08-24 04:56:11 -0700668/*
669 * bio_set is used to allow other portions of the IO system to
670 * allocate their own private memory pools for bio and iovec structures.
671 * These memory pools in turn all allocate from the bio_slab
672 * and the bvec_slabs[].
673 */
674#define BIO_POOL_SIZE 2
675#define BIOVEC_NR_POOLS 6
676#define BIOVEC_MAX_IDX (BIOVEC_NR_POOLS - 1)
677
678struct bio_set {
679 struct kmem_cache *bio_slab;
680 unsigned int front_pad;
681
682 mempool_t *bio_pool;
Kent Overstreet9f060e22012-10-12 15:29:33 -0700683 mempool_t *bvec_pool;
Kent Overstreet57fb2332012-08-24 04:56:11 -0700684#if defined(CONFIG_BLK_DEV_INTEGRITY)
685 mempool_t *bio_integrity_pool;
Kent Overstreet9f060e22012-10-12 15:29:33 -0700686 mempool_t *bvec_integrity_pool;
Kent Overstreet57fb2332012-08-24 04:56:11 -0700687#endif
Kent Overstreetdf2cb6d2012-09-10 14:33:46 -0700688
689 /*
690 * Deadlock avoidance for stacking block drivers: see comments in
691 * bio_alloc_bioset() for details
692 */
693 spinlock_t rescue_lock;
694 struct bio_list rescue_list;
695 struct work_struct rescue_work;
696 struct workqueue_struct *rescue_workqueue;
Kent Overstreet57fb2332012-08-24 04:56:11 -0700697};
698
699struct biovec_slab {
700 int nr_vecs;
701 char *name;
702 struct kmem_cache *slab;
703};
704
705/*
706 * a small number of entries is fine, not going to be performance critical.
707 * basically we just need to survive
708 */
709#define BIO_SPLIT_ENTRIES 2
710
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200711#if defined(CONFIG_BLK_DEV_INTEGRITY)
712
Kent Overstreetd57a5f72013-11-23 17:20:16 -0800713#define bip_for_each_vec(bvl, bip, iter) \
714 for_each_bvec(bvl, (bip)->bip_vec, iter, (bip)->bip_iter)
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200715
Martin K. Petersen13f05c82010-09-10 20:50:10 +0200716#define bio_for_each_integrity_vec(_bvl, _bio, _iter) \
717 for_each_bio(_bio) \
718 bip_for_each_vec(_bvl, _bio->bi_integrity, _iter)
719
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200720extern struct bio_integrity_payload *bio_integrity_alloc(struct bio *, gfp_t, unsigned int);
Kent Overstreet1e2a410f2012-09-06 15:34:56 -0700721extern void bio_integrity_free(struct bio *);
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200722extern int bio_integrity_add_page(struct bio *, struct page *, unsigned int, unsigned int);
Martin K. Petersene7258c12014-09-26 19:19:55 -0400723extern bool bio_integrity_enabled(struct bio *bio);
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200724extern int bio_integrity_prep(struct bio *);
Christoph Hellwig4246a0b2015-07-20 15:29:37 +0200725extern void bio_integrity_endio(struct bio *);
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200726extern void bio_integrity_advance(struct bio *, unsigned int);
727extern void bio_integrity_trim(struct bio *, unsigned int, unsigned int);
Kent Overstreet1e2a410f2012-09-06 15:34:56 -0700728extern int bio_integrity_clone(struct bio *, struct bio *, gfp_t);
Martin K. Petersen7878cba2009-06-26 15:37:49 +0200729extern int bioset_integrity_create(struct bio_set *, int);
730extern void bioset_integrity_free(struct bio_set *);
731extern void bio_integrity_init(void);
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200732
733#else /* CONFIG_BLK_DEV_INTEGRITY */
734
Martin K. Petersenc6115292014-09-26 19:20:08 -0400735static inline void *bio_integrity(struct bio *bio)
Martin K. Petersen6898e3b2012-01-13 08:15:33 +0100736{
Martin K. Petersenc6115292014-09-26 19:20:08 -0400737 return NULL;
Martin K. Petersen6898e3b2012-01-13 08:15:33 +0100738}
739
Martin K. Petersene7258c12014-09-26 19:19:55 -0400740static inline bool bio_integrity_enabled(struct bio *bio)
Martin K. Petersen6898e3b2012-01-13 08:15:33 +0100741{
Martin K. Petersene7258c12014-09-26 19:19:55 -0400742 return false;
Martin K. Petersen6898e3b2012-01-13 08:15:33 +0100743}
744
745static inline int bioset_integrity_create(struct bio_set *bs, int pool_size)
746{
747 return 0;
748}
749
750static inline void bioset_integrity_free (struct bio_set *bs)
751{
752 return;
753}
754
755static inline int bio_integrity_prep(struct bio *bio)
756{
757 return 0;
758}
759
Kent Overstreet1e2a410f2012-09-06 15:34:56 -0700760static inline void bio_integrity_free(struct bio *bio)
Martin K. Petersen6898e3b2012-01-13 08:15:33 +0100761{
762 return;
763}
764
Stephen Rothwell0c614e22011-11-16 09:21:48 +0100765static inline int bio_integrity_clone(struct bio *bio, struct bio *bio_src,
Kent Overstreet1e2a410f2012-09-06 15:34:56 -0700766 gfp_t gfp_mask)
Stephen Rothwell0c614e22011-11-16 09:21:48 +0100767{
768 return 0;
769}
Martin K. Petersen6898e3b2012-01-13 08:15:33 +0100770
Martin K. Petersen6898e3b2012-01-13 08:15:33 +0100771static inline void bio_integrity_advance(struct bio *bio,
772 unsigned int bytes_done)
773{
774 return;
775}
776
777static inline void bio_integrity_trim(struct bio *bio, unsigned int offset,
778 unsigned int sectors)
779{
780 return;
781}
782
783static inline void bio_integrity_init(void)
784{
785 return;
786}
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200787
Martin K. Petersenc6115292014-09-26 19:20:08 -0400788static inline bool bio_integrity_flagged(struct bio *bio, enum bip_flags flag)
789{
790 return false;
791}
792
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +0200793#endif /* CONFIG_BLK_DEV_INTEGRITY */
794
David Howells02a5e0a2007-08-11 22:34:32 +0200795#endif /* CONFIG_BLOCK */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700796#endif /* __LINUX_BIO_H */