Commit | Line | Data |
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1da177e4 LT |
1 | /* |
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 | |
12 | ||
13 | * 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> | |
22e2c507 | 25 | #include <linux/ioprio.h> |
1da177e4 | 26 | |
02a5e0ac DH |
27 | #ifdef CONFIG_BLOCK |
28 | ||
1da177e4 LT |
29 | #include <asm/io.h> |
30 | ||
1da177e4 LT |
31 | #define BIO_DEBUG |
32 | ||
33 | #ifdef BIO_DEBUG | |
34 | #define BIO_BUG_ON BUG_ON | |
35 | #else | |
36 | #define BIO_BUG_ON | |
37 | #endif | |
38 | ||
d84a8477 | 39 | #define BIO_MAX_PAGES 256 |
1da177e4 LT |
40 | #define BIO_MAX_SIZE (BIO_MAX_PAGES << PAGE_CACHE_SHIFT) |
41 | #define BIO_MAX_SECTORS (BIO_MAX_SIZE >> 9) | |
42 | ||
43 | /* | |
44 | * was unsigned short, but we might as well be ready for > 64kB I/O pages | |
45 | */ | |
46 | struct bio_vec { | |
47 | struct page *bv_page; | |
48 | unsigned int bv_len; | |
49 | unsigned int bv_offset; | |
50 | }; | |
51 | ||
52 | struct bio_set; | |
53 | struct bio; | |
7ba1ba12 | 54 | struct bio_integrity_payload; |
6712ecf8 | 55 | typedef void (bio_end_io_t) (struct bio *, int); |
1da177e4 LT |
56 | typedef void (bio_destructor_t) (struct bio *); |
57 | ||
58 | /* | |
59 | * main unit of I/O for the block layer and lower layers (ie drivers and | |
60 | * stacking drivers) | |
61 | */ | |
62 | struct bio { | |
2c2345c2 RG |
63 | sector_t bi_sector; /* device address in 512 byte |
64 | sectors */ | |
1da177e4 LT |
65 | struct bio *bi_next; /* request queue link */ |
66 | struct block_device *bi_bdev; | |
67 | unsigned long bi_flags; /* status, command, etc */ | |
68 | unsigned long bi_rw; /* bottom bits READ/WRITE, | |
69 | * top bits priority | |
70 | */ | |
71 | ||
72 | unsigned short bi_vcnt; /* how many bio_vec's */ | |
73 | unsigned short bi_idx; /* current index into bvl_vec */ | |
74 | ||
75 | /* Number of segments in this BIO after | |
76 | * physical address coalescing is performed. | |
77 | */ | |
5b99c2ff | 78 | unsigned int bi_phys_segments; |
1da177e4 | 79 | |
1da177e4 LT |
80 | unsigned int bi_size; /* residual I/O count */ |
81 | ||
86771427 FT |
82 | /* |
83 | * To keep track of the max segment size, we account for the | |
84 | * sizes of the first and last mergeable segments in this bio. | |
85 | */ | |
86 | unsigned int bi_seg_front_size; | |
87 | unsigned int bi_seg_back_size; | |
88 | ||
1da177e4 LT |
89 | unsigned int bi_max_vecs; /* max bvl_vecs we can hold */ |
90 | ||
c7c22e4d JA |
91 | unsigned int bi_comp_cpu; /* completion CPU */ |
92 | ||
ba744d5e RK |
93 | atomic_t bi_cnt; /* pin count */ |
94 | ||
1da177e4 LT |
95 | struct bio_vec *bi_io_vec; /* the actual vec list */ |
96 | ||
97 | bio_end_io_t *bi_end_io; | |
1da177e4 LT |
98 | |
99 | void *bi_private; | |
7ba1ba12 MP |
100 | #if defined(CONFIG_BLK_DEV_INTEGRITY) |
101 | struct bio_integrity_payload *bi_integrity; /* data integrity */ | |
102 | #endif | |
1da177e4 LT |
103 | |
104 | bio_destructor_t *bi_destructor; /* destructor */ | |
392ddc32 JA |
105 | |
106 | /* | |
107 | * We can inline a number of vecs at the end of the bio, to avoid | |
108 | * double allocations for a small number of bio_vecs. This member | |
109 | * MUST obviously be kept at the very end of the bio. | |
110 | */ | |
111 | struct bio_vec bi_inline_vecs[0]; | |
1da177e4 LT |
112 | }; |
113 | ||
114 | /* | |
115 | * bio flags | |
116 | */ | |
117 | #define BIO_UPTODATE 0 /* ok after I/O completion */ | |
118 | #define BIO_RW_BLOCK 1 /* RW_AHEAD set, and read/write would block */ | |
119 | #define BIO_EOF 2 /* out-out-bounds error */ | |
5df97b91 | 120 | #define BIO_SEG_VALID 3 /* bi_phys_segments valid */ |
1da177e4 LT |
121 | #define BIO_CLONED 4 /* doesn't own data */ |
122 | #define BIO_BOUNCED 5 /* bio is a bounce bio */ | |
123 | #define BIO_USER_MAPPED 6 /* contains user pages */ | |
124 | #define BIO_EOPNOTSUPP 7 /* not supported */ | |
c7c22e4d | 125 | #define BIO_CPU_AFFINE 8 /* complete bio on same CPU as submitted */ |
81882766 | 126 | #define BIO_NULL_MAPPED 9 /* contains invalid user pages */ |
74aa8c2c | 127 | #define BIO_FS_INTEGRITY 10 /* fs owns integrity data, not block layer */ |
08bafc03 | 128 | #define BIO_QUIET 11 /* Make BIO Quiet */ |
1da177e4 LT |
129 | #define bio_flagged(bio, flag) ((bio)->bi_flags & (1 << (flag))) |
130 | ||
131 | /* | |
132 | * top 4 bits of bio flags indicate the pool this bio came from | |
133 | */ | |
134 | #define BIO_POOL_BITS (4) | |
451a9ebf | 135 | #define BIO_POOL_NONE ((1UL << BIO_POOL_BITS) - 1) |
1da177e4 LT |
136 | #define BIO_POOL_OFFSET (BITS_PER_LONG - BIO_POOL_BITS) |
137 | #define BIO_POOL_MASK (1UL << BIO_POOL_OFFSET) | |
138 | #define BIO_POOL_IDX(bio) ((bio)->bi_flags >> BIO_POOL_OFFSET) | |
139 | ||
140 | /* | |
141 | * bio bi_rw flags | |
142 | * | |
af563942 JA |
143 | * bit 0 -- data direction |
144 | * If not set, bio is a read from device. If set, it's a write to device. | |
1da177e4 LT |
145 | * bit 1 -- rw-ahead when set |
146 | * bit 2 -- barrier | |
af563942 | 147 | * Insert a serialization point in the IO queue, forcing previously |
16642eb6 | 148 | * submitted IO to be completed before this one is issued. |
aeb6fafb JA |
149 | * bit 3 -- synchronous I/O hint. |
150 | * bit 4 -- Unplug the device immediately after submitting this bio. | |
151 | * bit 5 -- metadata request | |
af563942 JA |
152 | * Used for tracing to differentiate metadata and data IO. May also |
153 | * get some preferential treatment in the IO scheduler | |
aeb6fafb | 154 | * bit 6 -- discard sectors |
af563942 JA |
155 | * Informs the lower level device that this range of sectors is no longer |
156 | * used by the file system and may thus be freed by the device. Used | |
157 | * for flash based storage. | |
aeb6fafb JA |
158 | * bit 7 -- fail fast device errors |
159 | * bit 8 -- fail fast transport errors | |
160 | * bit 9 -- fail fast driver errors | |
6000a368 | 161 | * Don't want driver retries for any fast fail whatever the reason. |
aeb6fafb JA |
162 | * bit 10 -- Tell the IO scheduler not to wait for more requests after this |
163 | one has been submitted, even if it is a SYNC request. | |
1da177e4 | 164 | */ |
d628eaef DW |
165 | #define BIO_RW 0 /* Must match RW in req flags (blkdev.h) */ |
166 | #define BIO_RW_AHEAD 1 /* Must match FAILFAST in req flags */ | |
1da177e4 | 167 | #define BIO_RW_BARRIER 2 |
213d9417 JA |
168 | #define BIO_RW_SYNCIO 3 |
169 | #define BIO_RW_UNPLUG 4 | |
170 | #define BIO_RW_META 5 | |
171 | #define BIO_RW_DISCARD 6 | |
172 | #define BIO_RW_FAILFAST_DEV 7 | |
173 | #define BIO_RW_FAILFAST_TRANSPORT 8 | |
174 | #define BIO_RW_FAILFAST_DRIVER 9 | |
aeb6fafb | 175 | #define BIO_RW_NOIDLE 10 |
213d9417 | 176 | |
1dfa17f4 JA |
177 | #define bio_rw_flagged(bio, flag) ((bio)->bi_rw & (1 << (flag))) |
178 | ||
179 | /* | |
180 | * Old defines, these should eventually be replaced by direct usage of | |
181 | * bio_rw_flagged() | |
182 | */ | |
183 | #define bio_barrier(bio) bio_rw_flagged(bio, BIO_RW_BARRIER) | |
184 | #define bio_sync(bio) bio_rw_flagged(bio, BIO_RW_SYNCIO) | |
185 | #define bio_unplug(bio) bio_rw_flagged(bio, BIO_RW_UNPLUG) | |
186 | #define bio_failfast_dev(bio) bio_rw_flagged(bio, BIO_RW_FAILFAST_DEV) | |
187 | #define bio_failfast_transport(bio) \ | |
188 | bio_rw_flagged(bio, BIO_RW_FAILFAST_TRANSPORT) | |
189 | #define bio_failfast_driver(bio) \ | |
190 | bio_rw_flagged(bio, BIO_RW_FAILFAST_DRIVER) | |
191 | #define bio_rw_ahead(bio) bio_rw_flagged(bio, BIO_RW_AHEAD) | |
192 | #define bio_rw_meta(bio) bio_rw_flagged(bio, BIO_RW_META) | |
193 | #define bio_discard(bio) bio_rw_flagged(bio, BIO_RW_DISCARD) | |
aeb6fafb | 194 | #define bio_noidle(bio) bio_rw_flagged(bio, BIO_RW_NOIDLE) |
1dfa17f4 | 195 | |
22e2c507 JA |
196 | /* |
197 | * upper 16 bits of bi_rw define the io priority of this bio | |
198 | */ | |
199 | #define BIO_PRIO_SHIFT (8 * sizeof(unsigned long) - IOPRIO_BITS) | |
200 | #define bio_prio(bio) ((bio)->bi_rw >> BIO_PRIO_SHIFT) | |
201 | #define bio_prio_valid(bio) ioprio_valid(bio_prio(bio)) | |
202 | ||
203 | #define bio_set_prio(bio, prio) do { \ | |
204 | WARN_ON(prio >= (1 << IOPRIO_BITS)); \ | |
205 | (bio)->bi_rw &= ((1UL << BIO_PRIO_SHIFT) - 1); \ | |
206 | (bio)->bi_rw |= ((unsigned long) (prio) << BIO_PRIO_SHIFT); \ | |
207 | } while (0) | |
208 | ||
1da177e4 LT |
209 | /* |
210 | * various member access, note that bio_data should of course not be used | |
211 | * on highmem page vectors | |
212 | */ | |
213 | #define bio_iovec_idx(bio, idx) (&((bio)->bi_io_vec[(idx)])) | |
214 | #define bio_iovec(bio) bio_iovec_idx((bio), (bio)->bi_idx) | |
215 | #define bio_page(bio) bio_iovec((bio))->bv_page | |
216 | #define bio_offset(bio) bio_iovec((bio))->bv_offset | |
217 | #define bio_segments(bio) ((bio)->bi_vcnt - (bio)->bi_idx) | |
218 | #define bio_sectors(bio) ((bio)->bi_size >> 9) | |
e17fc0a1 | 219 | #define bio_empty_barrier(bio) (bio_barrier(bio) && !bio_has_data(bio) && !bio_discard(bio)) |
bf2de6f5 | 220 | |
2e46e8b2 | 221 | static inline unsigned int bio_cur_bytes(struct bio *bio) |
bf2de6f5 JA |
222 | { |
223 | if (bio->bi_vcnt) | |
2e46e8b2 | 224 | return bio_iovec(bio)->bv_len; |
fb2dce86 | 225 | else /* dataless requests such as discard */ |
2e46e8b2 | 226 | return bio->bi_size; |
bf2de6f5 JA |
227 | } |
228 | ||
229 | static inline void *bio_data(struct bio *bio) | |
230 | { | |
231 | if (bio->bi_vcnt) | |
232 | return page_address(bio_page(bio)) + bio_offset(bio); | |
233 | ||
234 | return NULL; | |
235 | } | |
1da177e4 | 236 | |
392ddc32 JA |
237 | static inline int bio_has_allocated_vec(struct bio *bio) |
238 | { | |
239 | return bio->bi_io_vec && bio->bi_io_vec != bio->bi_inline_vecs; | |
240 | } | |
241 | ||
1da177e4 LT |
242 | /* |
243 | * will die | |
244 | */ | |
245 | #define bio_to_phys(bio) (page_to_phys(bio_page((bio))) + (unsigned long) bio_offset((bio))) | |
246 | #define bvec_to_phys(bv) (page_to_phys((bv)->bv_page) + (unsigned long) (bv)->bv_offset) | |
247 | ||
248 | /* | |
249 | * queues that have highmem support enabled may still need to revert to | |
250 | * PIO transfers occasionally and thus map high pages temporarily. For | |
251 | * permanent PIO fall back, user is probably better off disabling highmem | |
252 | * I/O completely on that queue (see ide-dma for example) | |
253 | */ | |
254 | #define __bio_kmap_atomic(bio, idx, kmtype) \ | |
255 | (kmap_atomic(bio_iovec_idx((bio), (idx))->bv_page, kmtype) + \ | |
256 | bio_iovec_idx((bio), (idx))->bv_offset) | |
257 | ||
258 | #define __bio_kunmap_atomic(addr, kmtype) kunmap_atomic(addr, kmtype) | |
259 | ||
260 | /* | |
261 | * merge helpers etc | |
262 | */ | |
263 | ||
264 | #define __BVEC_END(bio) bio_iovec_idx((bio), (bio)->bi_vcnt - 1) | |
265 | #define __BVEC_START(bio) bio_iovec_idx((bio), (bio)->bi_idx) | |
266 | ||
f92131c3 JF |
267 | /* Default implementation of BIOVEC_PHYS_MERGEABLE */ |
268 | #define __BIOVEC_PHYS_MERGEABLE(vec1, vec2) \ | |
269 | ((bvec_to_phys((vec1)) + (vec1)->bv_len) == bvec_to_phys((vec2))) | |
270 | ||
1da177e4 LT |
271 | /* |
272 | * allow arch override, for eg virtualized architectures (put in asm/io.h) | |
273 | */ | |
274 | #ifndef BIOVEC_PHYS_MERGEABLE | |
275 | #define BIOVEC_PHYS_MERGEABLE(vec1, vec2) \ | |
f92131c3 | 276 | __BIOVEC_PHYS_MERGEABLE(vec1, vec2) |
1da177e4 LT |
277 | #endif |
278 | ||
1da177e4 LT |
279 | #define __BIO_SEG_BOUNDARY(addr1, addr2, mask) \ |
280 | (((addr1) | (mask)) == (((addr2) - 1) | (mask))) | |
281 | #define BIOVEC_SEG_BOUNDARY(q, b1, b2) \ | |
ae03bf63 | 282 | __BIO_SEG_BOUNDARY(bvec_to_phys((b1)), bvec_to_phys((b2)) + (b2)->bv_len, queue_segment_boundary((q))) |
1da177e4 LT |
283 | #define BIO_SEG_BOUNDARY(q, b1, b2) \ |
284 | BIOVEC_SEG_BOUNDARY((q), __BVEC_END((b1)), __BVEC_START((b2))) | |
285 | ||
6712ecf8 | 286 | #define bio_io_error(bio) bio_endio((bio), -EIO) |
1da177e4 LT |
287 | |
288 | /* | |
289 | * drivers should not use the __ version unless they _really_ want to | |
290 | * run through the entire bio and not just pending pieces | |
291 | */ | |
292 | #define __bio_for_each_segment(bvl, bio, i, start_idx) \ | |
293 | for (bvl = bio_iovec_idx((bio), (start_idx)), i = (start_idx); \ | |
294 | i < (bio)->bi_vcnt; \ | |
295 | bvl++, i++) | |
296 | ||
297 | #define bio_for_each_segment(bvl, bio, i) \ | |
298 | __bio_for_each_segment(bvl, bio, i, (bio)->bi_idx) | |
299 | ||
300 | /* | |
301 | * get a reference to a bio, so it won't disappear. the intended use is | |
302 | * something like: | |
303 | * | |
304 | * bio_get(bio); | |
305 | * submit_bio(rw, bio); | |
306 | * if (bio->bi_flags ...) | |
307 | * do_something | |
308 | * bio_put(bio); | |
309 | * | |
310 | * without the bio_get(), it could potentially complete I/O before submit_bio | |
311 | * returns. and then bio would be freed memory when if (bio->bi_flags ...) | |
312 | * runs | |
313 | */ | |
314 | #define bio_get(bio) atomic_inc(&(bio)->bi_cnt) | |
315 | ||
7ba1ba12 MP |
316 | #if defined(CONFIG_BLK_DEV_INTEGRITY) |
317 | /* | |
318 | * bio integrity payload | |
319 | */ | |
320 | struct bio_integrity_payload { | |
321 | struct bio *bip_bio; /* parent bio */ | |
7ba1ba12 MP |
322 | |
323 | sector_t bip_sector; /* virtual start sector */ | |
324 | ||
325 | void *bip_buf; /* generated integrity data */ | |
326 | bio_end_io_t *bip_end_io; /* saved I/O completion fn */ | |
327 | ||
7ba1ba12 MP |
328 | unsigned int bip_size; |
329 | ||
7878cba9 | 330 | unsigned short bip_slab; /* slab the bip came from */ |
7ba1ba12 MP |
331 | unsigned short bip_vcnt; /* # of integrity bio_vecs */ |
332 | unsigned short bip_idx; /* current bip_vec index */ | |
333 | ||
334 | struct work_struct bip_work; /* I/O completion */ | |
7878cba9 | 335 | struct bio_vec bip_vec[0]; /* embedded bvec array */ |
7ba1ba12 MP |
336 | }; |
337 | #endif /* CONFIG_BLK_DEV_INTEGRITY */ | |
1da177e4 LT |
338 | |
339 | /* | |
340 | * A bio_pair is used when we need to split a bio. | |
341 | * This can only happen for a bio that refers to just one | |
342 | * page of data, and in the unusual situation when the | |
343 | * page crosses a chunk/device boundary | |
344 | * | |
345 | * The address of the master bio is stored in bio1.bi_private | |
346 | * The address of the pool the pair was allocated from is stored | |
347 | * in bio2.bi_private | |
348 | */ | |
349 | struct bio_pair { | |
7ba1ba12 MP |
350 | struct bio bio1, bio2; |
351 | struct bio_vec bv1, bv2; | |
352 | #if defined(CONFIG_BLK_DEV_INTEGRITY) | |
353 | struct bio_integrity_payload bip1, bip2; | |
354 | struct bio_vec iv1, iv2; | |
355 | #endif | |
356 | atomic_t cnt; | |
357 | int error; | |
1da177e4 | 358 | }; |
6feef531 | 359 | extern struct bio_pair *bio_split(struct bio *bi, int first_sectors); |
1da177e4 LT |
360 | extern void bio_pair_release(struct bio_pair *dbio); |
361 | ||
bb799ca0 | 362 | extern struct bio_set *bioset_create(unsigned int, unsigned int); |
1da177e4 LT |
363 | extern void bioset_free(struct bio_set *); |
364 | ||
dd0fc66f | 365 | extern struct bio *bio_alloc(gfp_t, int); |
0a0d96b0 | 366 | extern struct bio *bio_kmalloc(gfp_t, int); |
dd0fc66f | 367 | extern struct bio *bio_alloc_bioset(gfp_t, int, struct bio_set *); |
1da177e4 | 368 | extern void bio_put(struct bio *); |
3676347a | 369 | extern void bio_free(struct bio *, struct bio_set *); |
1da177e4 | 370 | |
6712ecf8 | 371 | extern void bio_endio(struct bio *, int); |
1da177e4 LT |
372 | struct request_queue; |
373 | extern int bio_phys_segments(struct request_queue *, struct bio *); | |
1da177e4 LT |
374 | |
375 | extern void __bio_clone(struct bio *, struct bio *); | |
dd0fc66f | 376 | extern struct bio *bio_clone(struct bio *, gfp_t); |
1da177e4 LT |
377 | |
378 | extern void bio_init(struct bio *); | |
379 | ||
380 | extern int bio_add_page(struct bio *, struct page *, unsigned int,unsigned int); | |
6e68af66 MC |
381 | extern int bio_add_pc_page(struct request_queue *, struct bio *, struct page *, |
382 | unsigned int, unsigned int); | |
1da177e4 | 383 | extern int bio_get_nr_vecs(struct block_device *); |
ad3316bf | 384 | extern sector_t bio_sector_offset(struct bio *, unsigned short, unsigned int); |
1da177e4 | 385 | extern struct bio *bio_map_user(struct request_queue *, struct block_device *, |
a3bce90e | 386 | unsigned long, unsigned int, int, gfp_t); |
f1970baf | 387 | struct sg_iovec; |
152e283f | 388 | struct rq_map_data; |
f1970baf JB |
389 | extern struct bio *bio_map_user_iov(struct request_queue *, |
390 | struct block_device *, | |
a3bce90e | 391 | struct sg_iovec *, int, int, gfp_t); |
1da177e4 | 392 | extern void bio_unmap_user(struct bio *); |
df46b9a4 | 393 | extern struct bio *bio_map_kern(struct request_queue *, void *, unsigned int, |
27496a8c | 394 | gfp_t); |
68154e90 FT |
395 | extern struct bio *bio_copy_kern(struct request_queue *, void *, unsigned int, |
396 | gfp_t, int); | |
1da177e4 LT |
397 | extern void bio_set_pages_dirty(struct bio *bio); |
398 | extern void bio_check_pages_dirty(struct bio *bio); | |
152e283f FT |
399 | extern struct bio *bio_copy_user(struct request_queue *, struct rq_map_data *, |
400 | unsigned long, unsigned int, int, gfp_t); | |
401 | extern struct bio *bio_copy_user_iov(struct request_queue *, | |
402 | struct rq_map_data *, struct sg_iovec *, | |
a3bce90e | 403 | int, int, gfp_t); |
1da177e4 LT |
404 | extern int bio_uncopy_user(struct bio *); |
405 | void zero_fill_bio(struct bio *bio); | |
51d654e1 | 406 | extern struct bio_vec *bvec_alloc_bs(gfp_t, int, unsigned long *, struct bio_set *); |
bb799ca0 | 407 | extern void bvec_free_bs(struct bio_set *, struct bio_vec *, unsigned int); |
7ba1ba12 | 408 | extern unsigned int bvec_nr_vecs(unsigned short idx); |
51d654e1 | 409 | |
c7c22e4d JA |
410 | /* |
411 | * Allow queuer to specify a completion CPU for this bio | |
412 | */ | |
413 | static inline void bio_set_completion_cpu(struct bio *bio, unsigned int cpu) | |
414 | { | |
415 | bio->bi_comp_cpu = cpu; | |
416 | } | |
417 | ||
51d654e1 MP |
418 | /* |
419 | * bio_set is used to allow other portions of the IO system to | |
420 | * allocate their own private memory pools for bio and iovec structures. | |
421 | * These memory pools in turn all allocate from the bio_slab | |
422 | * and the bvec_slabs[]. | |
423 | */ | |
424 | #define BIO_POOL_SIZE 2 | |
425 | #define BIOVEC_NR_POOLS 6 | |
7ff9345f | 426 | #define BIOVEC_MAX_IDX (BIOVEC_NR_POOLS - 1) |
51d654e1 MP |
427 | |
428 | struct bio_set { | |
1b434498 | 429 | struct kmem_cache *bio_slab; |
bb799ca0 JA |
430 | unsigned int front_pad; |
431 | ||
51d654e1 | 432 | mempool_t *bio_pool; |
7878cba9 MP |
433 | #if defined(CONFIG_BLK_DEV_INTEGRITY) |
434 | mempool_t *bio_integrity_pool; | |
435 | #endif | |
7ff9345f | 436 | mempool_t *bvec_pool; |
51d654e1 MP |
437 | }; |
438 | ||
439 | struct biovec_slab { | |
440 | int nr_vecs; | |
441 | char *name; | |
442 | struct kmem_cache *slab; | |
443 | }; | |
444 | ||
445 | extern struct bio_set *fs_bio_set; | |
bb799ca0 | 446 | extern struct biovec_slab bvec_slabs[BIOVEC_NR_POOLS] __read_mostly; |
51d654e1 MP |
447 | |
448 | /* | |
449 | * a small number of entries is fine, not going to be performance critical. | |
450 | * basically we just need to survive | |
451 | */ | |
452 | #define BIO_SPLIT_ENTRIES 2 | |
1da177e4 LT |
453 | |
454 | #ifdef CONFIG_HIGHMEM | |
455 | /* | |
20b636bf AB |
456 | * remember never ever reenable interrupts between a bvec_kmap_irq and |
457 | * bvec_kunmap_irq! | |
1da177e4 LT |
458 | * |
459 | * This function MUST be inlined - it plays with the CPU interrupt flags. | |
1da177e4 | 460 | */ |
c52440a6 AB |
461 | static __always_inline char *bvec_kmap_irq(struct bio_vec *bvec, |
462 | unsigned long *flags) | |
1da177e4 LT |
463 | { |
464 | unsigned long addr; | |
465 | ||
466 | /* | |
467 | * might not be a highmem page, but the preempt/irq count | |
468 | * balancing is a lot nicer this way | |
469 | */ | |
470 | local_irq_save(*flags); | |
471 | addr = (unsigned long) kmap_atomic(bvec->bv_page, KM_BIO_SRC_IRQ); | |
472 | ||
473 | BUG_ON(addr & ~PAGE_MASK); | |
474 | ||
475 | return (char *) addr + bvec->bv_offset; | |
476 | } | |
477 | ||
c52440a6 AB |
478 | static __always_inline void bvec_kunmap_irq(char *buffer, |
479 | unsigned long *flags) | |
1da177e4 LT |
480 | { |
481 | unsigned long ptr = (unsigned long) buffer & PAGE_MASK; | |
482 | ||
483 | kunmap_atomic((void *) ptr, KM_BIO_SRC_IRQ); | |
484 | local_irq_restore(*flags); | |
485 | } | |
486 | ||
487 | #else | |
488 | #define bvec_kmap_irq(bvec, flags) (page_address((bvec)->bv_page) + (bvec)->bv_offset) | |
489 | #define bvec_kunmap_irq(buf, flags) do { *(flags) = 0; } while (0) | |
490 | #endif | |
491 | ||
c2d08dad | 492 | static inline char *__bio_kmap_irq(struct bio *bio, unsigned short idx, |
1da177e4 LT |
493 | unsigned long *flags) |
494 | { | |
495 | return bvec_kmap_irq(bio_iovec_idx(bio, idx), flags); | |
496 | } | |
497 | #define __bio_kunmap_irq(buf, flags) bvec_kunmap_irq(buf, flags) | |
498 | ||
499 | #define bio_kmap_irq(bio, flags) \ | |
500 | __bio_kmap_irq((bio), (bio)->bi_idx, (flags)) | |
501 | #define bio_kunmap_irq(buf,flags) __bio_kunmap_irq(buf, flags) | |
502 | ||
7a67f63b JA |
503 | /* |
504 | * Check whether this bio carries any data or not. A NULL bio is allowed. | |
505 | */ | |
506 | static inline int bio_has_data(struct bio *bio) | |
507 | { | |
508 | return bio && bio->bi_io_vec != NULL; | |
509 | } | |
510 | ||
8f3d8ba2 | 511 | /* |
e686307f | 512 | * BIO list management for use by remapping drivers (e.g. DM or MD) and loop. |
8f3d8ba2 CH |
513 | * |
514 | * A bio_list anchors a singly-linked list of bios chained through the bi_next | |
515 | * member of the bio. The bio_list also caches the last list member to allow | |
516 | * fast access to the tail. | |
517 | */ | |
518 | struct bio_list { | |
519 | struct bio *head; | |
520 | struct bio *tail; | |
521 | }; | |
522 | ||
523 | static inline int bio_list_empty(const struct bio_list *bl) | |
524 | { | |
525 | return bl->head == NULL; | |
526 | } | |
527 | ||
528 | static inline void bio_list_init(struct bio_list *bl) | |
529 | { | |
530 | bl->head = bl->tail = NULL; | |
531 | } | |
532 | ||
533 | #define bio_list_for_each(bio, bl) \ | |
534 | for (bio = (bl)->head; bio; bio = bio->bi_next) | |
535 | ||
536 | static inline unsigned bio_list_size(const struct bio_list *bl) | |
537 | { | |
538 | unsigned sz = 0; | |
539 | struct bio *bio; | |
540 | ||
541 | bio_list_for_each(bio, bl) | |
542 | sz++; | |
543 | ||
544 | return sz; | |
545 | } | |
546 | ||
547 | static inline void bio_list_add(struct bio_list *bl, struct bio *bio) | |
548 | { | |
549 | bio->bi_next = NULL; | |
550 | ||
551 | if (bl->tail) | |
552 | bl->tail->bi_next = bio; | |
553 | else | |
554 | bl->head = bio; | |
555 | ||
556 | bl->tail = bio; | |
557 | } | |
558 | ||
559 | static inline void bio_list_add_head(struct bio_list *bl, struct bio *bio) | |
560 | { | |
561 | bio->bi_next = bl->head; | |
562 | ||
563 | bl->head = bio; | |
564 | ||
565 | if (!bl->tail) | |
566 | bl->tail = bio; | |
567 | } | |
568 | ||
569 | static inline void bio_list_merge(struct bio_list *bl, struct bio_list *bl2) | |
570 | { | |
571 | if (!bl2->head) | |
572 | return; | |
573 | ||
574 | if (bl->tail) | |
575 | bl->tail->bi_next = bl2->head; | |
576 | else | |
577 | bl->head = bl2->head; | |
578 | ||
579 | bl->tail = bl2->tail; | |
580 | } | |
581 | ||
582 | static inline void bio_list_merge_head(struct bio_list *bl, | |
583 | struct bio_list *bl2) | |
584 | { | |
585 | if (!bl2->head) | |
586 | return; | |
587 | ||
588 | if (bl->head) | |
589 | bl2->tail->bi_next = bl->head; | |
590 | else | |
591 | bl->tail = bl2->tail; | |
592 | ||
593 | bl->head = bl2->head; | |
594 | } | |
595 | ||
13685a16 GU |
596 | static inline struct bio *bio_list_peek(struct bio_list *bl) |
597 | { | |
598 | return bl->head; | |
599 | } | |
600 | ||
8f3d8ba2 CH |
601 | static inline struct bio *bio_list_pop(struct bio_list *bl) |
602 | { | |
603 | struct bio *bio = bl->head; | |
604 | ||
605 | if (bio) { | |
606 | bl->head = bl->head->bi_next; | |
607 | if (!bl->head) | |
608 | bl->tail = NULL; | |
609 | ||
610 | bio->bi_next = NULL; | |
611 | } | |
612 | ||
613 | return bio; | |
614 | } | |
615 | ||
616 | static inline struct bio *bio_list_get(struct bio_list *bl) | |
617 | { | |
618 | struct bio *bio = bl->head; | |
619 | ||
620 | bl->head = bl->tail = NULL; | |
621 | ||
622 | return bio; | |
623 | } | |
624 | ||
7ba1ba12 MP |
625 | #if defined(CONFIG_BLK_DEV_INTEGRITY) |
626 | ||
627 | #define bip_vec_idx(bip, idx) (&(bip->bip_vec[(idx)])) | |
628 | #define bip_vec(bip) bip_vec_idx(bip, 0) | |
629 | ||
630 | #define __bip_for_each_vec(bvl, bip, i, start_idx) \ | |
631 | for (bvl = bip_vec_idx((bip), (start_idx)), i = (start_idx); \ | |
632 | i < (bip)->bip_vcnt; \ | |
633 | bvl++, i++) | |
634 | ||
635 | #define bip_for_each_vec(bvl, bip, i) \ | |
636 | __bip_for_each_vec(bvl, bip, i, (bip)->bip_idx) | |
637 | ||
8deaf721 | 638 | #define bio_integrity(bio) (bio->bi_integrity != NULL) |
7ba1ba12 | 639 | |
7878cba9 | 640 | extern struct bio_integrity_payload *bio_integrity_alloc_bioset(struct bio *, gfp_t, unsigned int, struct bio_set *); |
7ba1ba12 | 641 | extern struct bio_integrity_payload *bio_integrity_alloc(struct bio *, gfp_t, unsigned int); |
7878cba9 | 642 | extern void bio_integrity_free(struct bio *, struct bio_set *); |
7ba1ba12 MP |
643 | extern int bio_integrity_add_page(struct bio *, struct page *, unsigned int, unsigned int); |
644 | extern int bio_integrity_enabled(struct bio *bio); | |
645 | extern int bio_integrity_set_tag(struct bio *, void *, unsigned int); | |
646 | extern int bio_integrity_get_tag(struct bio *, void *, unsigned int); | |
647 | extern int bio_integrity_prep(struct bio *); | |
648 | extern void bio_integrity_endio(struct bio *, int); | |
649 | extern void bio_integrity_advance(struct bio *, unsigned int); | |
650 | extern void bio_integrity_trim(struct bio *, unsigned int, unsigned int); | |
651 | extern void bio_integrity_split(struct bio *, struct bio_pair *, int); | |
7878cba9 MP |
652 | extern int bio_integrity_clone(struct bio *, struct bio *, gfp_t, struct bio_set *); |
653 | extern int bioset_integrity_create(struct bio_set *, int); | |
654 | extern void bioset_integrity_free(struct bio_set *); | |
655 | extern void bio_integrity_init(void); | |
7ba1ba12 MP |
656 | |
657 | #else /* CONFIG_BLK_DEV_INTEGRITY */ | |
658 | ||
659 | #define bio_integrity(a) (0) | |
7878cba9 | 660 | #define bioset_integrity_create(a, b) (0) |
7ba1ba12 MP |
661 | #define bio_integrity_prep(a) (0) |
662 | #define bio_integrity_enabled(a) (0) | |
7878cba9 MP |
663 | #define bio_integrity_clone(a, b, c, d) (0) |
664 | #define bioset_integrity_free(a) do { } while (0) | |
665 | #define bio_integrity_free(a, b) do { } while (0) | |
7ba1ba12 MP |
666 | #define bio_integrity_endio(a, b) do { } while (0) |
667 | #define bio_integrity_advance(a, b) do { } while (0) | |
668 | #define bio_integrity_trim(a, b, c) do { } while (0) | |
669 | #define bio_integrity_split(a, b, c) do { } while (0) | |
670 | #define bio_integrity_set_tag(a, b, c) do { } while (0) | |
671 | #define bio_integrity_get_tag(a, b, c) do { } while (0) | |
7878cba9 | 672 | #define bio_integrity_init(a) do { } while (0) |
7ba1ba12 MP |
673 | |
674 | #endif /* CONFIG_BLK_DEV_INTEGRITY */ | |
675 | ||
02a5e0ac | 676 | #endif /* CONFIG_BLOCK */ |
1da177e4 | 677 | #endif /* __LINUX_BIO_H */ |