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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) | |
135 | #define BIO_POOL_OFFSET (BITS_PER_LONG - BIO_POOL_BITS) | |
136 | #define BIO_POOL_MASK (1UL << BIO_POOL_OFFSET) | |
137 | #define BIO_POOL_IDX(bio) ((bio)->bi_flags >> BIO_POOL_OFFSET) | |
138 | ||
139 | /* | |
140 | * bio bi_rw flags | |
141 | * | |
af563942 JA |
142 | * bit 0 -- data direction |
143 | * If not set, bio is a read from device. If set, it's a write to device. | |
1da177e4 LT |
144 | * bit 1 -- rw-ahead when set |
145 | * bit 2 -- barrier | |
af563942 JA |
146 | * Insert a serialization point in the IO queue, forcing previously |
147 | * submitted IO to be completed before this oen is issued. | |
6000a368 | 148 | * bit 3 -- synchronous I/O hint: the block layer will unplug immediately |
af563942 JA |
149 | * Note that this does NOT indicate that the IO itself is sync, just |
150 | * that the block layer will not postpone issue of this IO by plugging. | |
6000a368 | 151 | * bit 4 -- 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 | |
6000a368 | 154 | * bit 5 -- 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. | |
6000a368 MC |
158 | * bit 6 -- fail fast device errors |
159 | * bit 7 -- fail fast transport errors | |
160 | * bit 8 -- fail fast driver errors | |
161 | * Don't want driver retries for any fast fail whatever the reason. | |
1da177e4 | 162 | */ |
d628eaef DW |
163 | #define BIO_RW 0 /* Must match RW in req flags (blkdev.h) */ |
164 | #define BIO_RW_AHEAD 1 /* Must match FAILFAST in req flags */ | |
1da177e4 | 165 | #define BIO_RW_BARRIER 2 |
6000a368 MC |
166 | #define BIO_RW_SYNC 3 |
167 | #define BIO_RW_META 4 | |
168 | #define BIO_RW_DISCARD 5 | |
169 | #define BIO_RW_FAILFAST_DEV 6 | |
170 | #define BIO_RW_FAILFAST_TRANSPORT 7 | |
171 | #define BIO_RW_FAILFAST_DRIVER 8 | |
1da177e4 | 172 | |
22e2c507 JA |
173 | /* |
174 | * upper 16 bits of bi_rw define the io priority of this bio | |
175 | */ | |
176 | #define BIO_PRIO_SHIFT (8 * sizeof(unsigned long) - IOPRIO_BITS) | |
177 | #define bio_prio(bio) ((bio)->bi_rw >> BIO_PRIO_SHIFT) | |
178 | #define bio_prio_valid(bio) ioprio_valid(bio_prio(bio)) | |
179 | ||
180 | #define bio_set_prio(bio, prio) do { \ | |
181 | WARN_ON(prio >= (1 << IOPRIO_BITS)); \ | |
182 | (bio)->bi_rw &= ((1UL << BIO_PRIO_SHIFT) - 1); \ | |
183 | (bio)->bi_rw |= ((unsigned long) (prio) << BIO_PRIO_SHIFT); \ | |
184 | } while (0) | |
185 | ||
1da177e4 LT |
186 | /* |
187 | * various member access, note that bio_data should of course not be used | |
188 | * on highmem page vectors | |
189 | */ | |
190 | #define bio_iovec_idx(bio, idx) (&((bio)->bi_io_vec[(idx)])) | |
191 | #define bio_iovec(bio) bio_iovec_idx((bio), (bio)->bi_idx) | |
192 | #define bio_page(bio) bio_iovec((bio))->bv_page | |
193 | #define bio_offset(bio) bio_iovec((bio))->bv_offset | |
194 | #define bio_segments(bio) ((bio)->bi_vcnt - (bio)->bi_idx) | |
195 | #define bio_sectors(bio) ((bio)->bi_size >> 9) | |
1da177e4 LT |
196 | #define bio_barrier(bio) ((bio)->bi_rw & (1 << BIO_RW_BARRIER)) |
197 | #define bio_sync(bio) ((bio)->bi_rw & (1 << BIO_RW_SYNC)) | |
6000a368 MC |
198 | #define bio_failfast_dev(bio) ((bio)->bi_rw & (1 << BIO_RW_FAILFAST_DEV)) |
199 | #define bio_failfast_transport(bio) \ | |
200 | ((bio)->bi_rw & (1 << BIO_RW_FAILFAST_TRANSPORT)) | |
201 | #define bio_failfast_driver(bio) ((bio)->bi_rw & (1 << BIO_RW_FAILFAST_DRIVER)) | |
1da177e4 | 202 | #define bio_rw_ahead(bio) ((bio)->bi_rw & (1 << BIO_RW_AHEAD)) |
5404bc7a | 203 | #define bio_rw_meta(bio) ((bio)->bi_rw & (1 << BIO_RW_META)) |
fb2dce86 | 204 | #define bio_discard(bio) ((bio)->bi_rw & (1 << BIO_RW_DISCARD)) |
e17fc0a1 | 205 | #define bio_empty_barrier(bio) (bio_barrier(bio) && !bio_has_data(bio) && !bio_discard(bio)) |
bf2de6f5 JA |
206 | |
207 | static inline unsigned int bio_cur_sectors(struct bio *bio) | |
208 | { | |
209 | if (bio->bi_vcnt) | |
210 | return bio_iovec(bio)->bv_len >> 9; | |
fb2dce86 DW |
211 | else /* dataless requests such as discard */ |
212 | return bio->bi_size >> 9; | |
bf2de6f5 JA |
213 | } |
214 | ||
215 | static inline void *bio_data(struct bio *bio) | |
216 | { | |
217 | if (bio->bi_vcnt) | |
218 | return page_address(bio_page(bio)) + bio_offset(bio); | |
219 | ||
220 | return NULL; | |
221 | } | |
1da177e4 | 222 | |
392ddc32 JA |
223 | static inline int bio_has_allocated_vec(struct bio *bio) |
224 | { | |
225 | return bio->bi_io_vec && bio->bi_io_vec != bio->bi_inline_vecs; | |
226 | } | |
227 | ||
1da177e4 LT |
228 | /* |
229 | * will die | |
230 | */ | |
231 | #define bio_to_phys(bio) (page_to_phys(bio_page((bio))) + (unsigned long) bio_offset((bio))) | |
232 | #define bvec_to_phys(bv) (page_to_phys((bv)->bv_page) + (unsigned long) (bv)->bv_offset) | |
233 | ||
234 | /* | |
235 | * queues that have highmem support enabled may still need to revert to | |
236 | * PIO transfers occasionally and thus map high pages temporarily. For | |
237 | * permanent PIO fall back, user is probably better off disabling highmem | |
238 | * I/O completely on that queue (see ide-dma for example) | |
239 | */ | |
240 | #define __bio_kmap_atomic(bio, idx, kmtype) \ | |
241 | (kmap_atomic(bio_iovec_idx((bio), (idx))->bv_page, kmtype) + \ | |
242 | bio_iovec_idx((bio), (idx))->bv_offset) | |
243 | ||
244 | #define __bio_kunmap_atomic(addr, kmtype) kunmap_atomic(addr, kmtype) | |
245 | ||
246 | /* | |
247 | * merge helpers etc | |
248 | */ | |
249 | ||
250 | #define __BVEC_END(bio) bio_iovec_idx((bio), (bio)->bi_vcnt - 1) | |
251 | #define __BVEC_START(bio) bio_iovec_idx((bio), (bio)->bi_idx) | |
252 | ||
f92131c3 JF |
253 | /* Default implementation of BIOVEC_PHYS_MERGEABLE */ |
254 | #define __BIOVEC_PHYS_MERGEABLE(vec1, vec2) \ | |
255 | ((bvec_to_phys((vec1)) + (vec1)->bv_len) == bvec_to_phys((vec2))) | |
256 | ||
1da177e4 LT |
257 | /* |
258 | * allow arch override, for eg virtualized architectures (put in asm/io.h) | |
259 | */ | |
260 | #ifndef BIOVEC_PHYS_MERGEABLE | |
261 | #define BIOVEC_PHYS_MERGEABLE(vec1, vec2) \ | |
f92131c3 | 262 | __BIOVEC_PHYS_MERGEABLE(vec1, vec2) |
1da177e4 LT |
263 | #endif |
264 | ||
1da177e4 LT |
265 | #define __BIO_SEG_BOUNDARY(addr1, addr2, mask) \ |
266 | (((addr1) | (mask)) == (((addr2) - 1) | (mask))) | |
267 | #define BIOVEC_SEG_BOUNDARY(q, b1, b2) \ | |
268 | __BIO_SEG_BOUNDARY(bvec_to_phys((b1)), bvec_to_phys((b2)) + (b2)->bv_len, (q)->seg_boundary_mask) | |
269 | #define BIO_SEG_BOUNDARY(q, b1, b2) \ | |
270 | BIOVEC_SEG_BOUNDARY((q), __BVEC_END((b1)), __BVEC_START((b2))) | |
271 | ||
6712ecf8 | 272 | #define bio_io_error(bio) bio_endio((bio), -EIO) |
1da177e4 LT |
273 | |
274 | /* | |
275 | * drivers should not use the __ version unless they _really_ want to | |
276 | * run through the entire bio and not just pending pieces | |
277 | */ | |
278 | #define __bio_for_each_segment(bvl, bio, i, start_idx) \ | |
279 | for (bvl = bio_iovec_idx((bio), (start_idx)), i = (start_idx); \ | |
280 | i < (bio)->bi_vcnt; \ | |
281 | bvl++, i++) | |
282 | ||
283 | #define bio_for_each_segment(bvl, bio, i) \ | |
284 | __bio_for_each_segment(bvl, bio, i, (bio)->bi_idx) | |
285 | ||
286 | /* | |
287 | * get a reference to a bio, so it won't disappear. the intended use is | |
288 | * something like: | |
289 | * | |
290 | * bio_get(bio); | |
291 | * submit_bio(rw, bio); | |
292 | * if (bio->bi_flags ...) | |
293 | * do_something | |
294 | * bio_put(bio); | |
295 | * | |
296 | * without the bio_get(), it could potentially complete I/O before submit_bio | |
297 | * returns. and then bio would be freed memory when if (bio->bi_flags ...) | |
298 | * runs | |
299 | */ | |
300 | #define bio_get(bio) atomic_inc(&(bio)->bi_cnt) | |
301 | ||
7ba1ba12 MP |
302 | #if defined(CONFIG_BLK_DEV_INTEGRITY) |
303 | /* | |
304 | * bio integrity payload | |
305 | */ | |
306 | struct bio_integrity_payload { | |
307 | struct bio *bip_bio; /* parent bio */ | |
308 | struct bio_vec *bip_vec; /* integrity data vector */ | |
309 | ||
310 | sector_t bip_sector; /* virtual start sector */ | |
311 | ||
312 | void *bip_buf; /* generated integrity data */ | |
313 | bio_end_io_t *bip_end_io; /* saved I/O completion fn */ | |
314 | ||
7ba1ba12 MP |
315 | unsigned int bip_size; |
316 | ||
317 | unsigned short bip_pool; /* pool the ivec came from */ | |
318 | unsigned short bip_vcnt; /* # of integrity bio_vecs */ | |
319 | unsigned short bip_idx; /* current bip_vec index */ | |
320 | ||
321 | struct work_struct bip_work; /* I/O completion */ | |
322 | }; | |
323 | #endif /* CONFIG_BLK_DEV_INTEGRITY */ | |
1da177e4 LT |
324 | |
325 | /* | |
326 | * A bio_pair is used when we need to split a bio. | |
327 | * This can only happen for a bio that refers to just one | |
328 | * page of data, and in the unusual situation when the | |
329 | * page crosses a chunk/device boundary | |
330 | * | |
331 | * The address of the master bio is stored in bio1.bi_private | |
332 | * The address of the pool the pair was allocated from is stored | |
333 | * in bio2.bi_private | |
334 | */ | |
335 | struct bio_pair { | |
7ba1ba12 MP |
336 | struct bio bio1, bio2; |
337 | struct bio_vec bv1, bv2; | |
338 | #if defined(CONFIG_BLK_DEV_INTEGRITY) | |
339 | struct bio_integrity_payload bip1, bip2; | |
340 | struct bio_vec iv1, iv2; | |
341 | #endif | |
342 | atomic_t cnt; | |
343 | int error; | |
1da177e4 | 344 | }; |
6feef531 | 345 | extern struct bio_pair *bio_split(struct bio *bi, int first_sectors); |
1da177e4 LT |
346 | extern void bio_pair_release(struct bio_pair *dbio); |
347 | ||
bb799ca0 | 348 | extern struct bio_set *bioset_create(unsigned int, unsigned int); |
1da177e4 LT |
349 | extern void bioset_free(struct bio_set *); |
350 | ||
dd0fc66f | 351 | extern struct bio *bio_alloc(gfp_t, int); |
0a0d96b0 | 352 | extern struct bio *bio_kmalloc(gfp_t, int); |
dd0fc66f | 353 | extern struct bio *bio_alloc_bioset(gfp_t, int, struct bio_set *); |
1da177e4 | 354 | extern void bio_put(struct bio *); |
3676347a | 355 | extern void bio_free(struct bio *, struct bio_set *); |
1da177e4 | 356 | |
6712ecf8 | 357 | extern void bio_endio(struct bio *, int); |
1da177e4 LT |
358 | struct request_queue; |
359 | extern int bio_phys_segments(struct request_queue *, struct bio *); | |
1da177e4 LT |
360 | |
361 | extern void __bio_clone(struct bio *, struct bio *); | |
dd0fc66f | 362 | extern struct bio *bio_clone(struct bio *, gfp_t); |
1da177e4 LT |
363 | |
364 | extern void bio_init(struct bio *); | |
365 | ||
366 | extern int bio_add_page(struct bio *, struct page *, unsigned int,unsigned int); | |
6e68af66 MC |
367 | extern int bio_add_pc_page(struct request_queue *, struct bio *, struct page *, |
368 | unsigned int, unsigned int); | |
1da177e4 | 369 | extern int bio_get_nr_vecs(struct block_device *); |
ad3316bf | 370 | extern sector_t bio_sector_offset(struct bio *, unsigned short, unsigned int); |
1da177e4 | 371 | extern struct bio *bio_map_user(struct request_queue *, struct block_device *, |
a3bce90e | 372 | unsigned long, unsigned int, int, gfp_t); |
f1970baf | 373 | struct sg_iovec; |
152e283f | 374 | struct rq_map_data; |
f1970baf JB |
375 | extern struct bio *bio_map_user_iov(struct request_queue *, |
376 | struct block_device *, | |
a3bce90e | 377 | struct sg_iovec *, int, int, gfp_t); |
1da177e4 | 378 | extern void bio_unmap_user(struct bio *); |
df46b9a4 | 379 | extern struct bio *bio_map_kern(struct request_queue *, void *, unsigned int, |
27496a8c | 380 | gfp_t); |
68154e90 FT |
381 | extern struct bio *bio_copy_kern(struct request_queue *, void *, unsigned int, |
382 | gfp_t, int); | |
1da177e4 LT |
383 | extern void bio_set_pages_dirty(struct bio *bio); |
384 | extern void bio_check_pages_dirty(struct bio *bio); | |
152e283f FT |
385 | extern struct bio *bio_copy_user(struct request_queue *, struct rq_map_data *, |
386 | unsigned long, unsigned int, int, gfp_t); | |
387 | extern struct bio *bio_copy_user_iov(struct request_queue *, | |
388 | struct rq_map_data *, struct sg_iovec *, | |
a3bce90e | 389 | int, int, gfp_t); |
1da177e4 LT |
390 | extern int bio_uncopy_user(struct bio *); |
391 | void zero_fill_bio(struct bio *bio); | |
51d654e1 | 392 | extern struct bio_vec *bvec_alloc_bs(gfp_t, int, unsigned long *, struct bio_set *); |
bb799ca0 | 393 | extern void bvec_free_bs(struct bio_set *, struct bio_vec *, unsigned int); |
7ba1ba12 | 394 | extern unsigned int bvec_nr_vecs(unsigned short idx); |
51d654e1 | 395 | |
c7c22e4d JA |
396 | /* |
397 | * Allow queuer to specify a completion CPU for this bio | |
398 | */ | |
399 | static inline void bio_set_completion_cpu(struct bio *bio, unsigned int cpu) | |
400 | { | |
401 | bio->bi_comp_cpu = cpu; | |
402 | } | |
403 | ||
51d654e1 MP |
404 | /* |
405 | * bio_set is used to allow other portions of the IO system to | |
406 | * allocate their own private memory pools for bio and iovec structures. | |
407 | * These memory pools in turn all allocate from the bio_slab | |
408 | * and the bvec_slabs[]. | |
409 | */ | |
410 | #define BIO_POOL_SIZE 2 | |
411 | #define BIOVEC_NR_POOLS 6 | |
7ff9345f | 412 | #define BIOVEC_MAX_IDX (BIOVEC_NR_POOLS - 1) |
51d654e1 MP |
413 | |
414 | struct bio_set { | |
1b434498 | 415 | struct kmem_cache *bio_slab; |
bb799ca0 JA |
416 | unsigned int front_pad; |
417 | ||
51d654e1 | 418 | mempool_t *bio_pool; |
7ba1ba12 MP |
419 | #if defined(CONFIG_BLK_DEV_INTEGRITY) |
420 | mempool_t *bio_integrity_pool; | |
421 | #endif | |
7ff9345f | 422 | mempool_t *bvec_pool; |
51d654e1 MP |
423 | }; |
424 | ||
425 | struct biovec_slab { | |
426 | int nr_vecs; | |
427 | char *name; | |
428 | struct kmem_cache *slab; | |
429 | }; | |
430 | ||
431 | extern struct bio_set *fs_bio_set; | |
bb799ca0 | 432 | extern struct biovec_slab bvec_slabs[BIOVEC_NR_POOLS] __read_mostly; |
51d654e1 MP |
433 | |
434 | /* | |
435 | * a small number of entries is fine, not going to be performance critical. | |
436 | * basically we just need to survive | |
437 | */ | |
438 | #define BIO_SPLIT_ENTRIES 2 | |
1da177e4 LT |
439 | |
440 | #ifdef CONFIG_HIGHMEM | |
441 | /* | |
442 | * remember to add offset! and never ever reenable interrupts between a | |
443 | * bvec_kmap_irq and bvec_kunmap_irq!! | |
444 | * | |
445 | * This function MUST be inlined - it plays with the CPU interrupt flags. | |
1da177e4 | 446 | */ |
c2d08dad | 447 | static inline char *bvec_kmap_irq(struct bio_vec *bvec, unsigned long *flags) |
1da177e4 LT |
448 | { |
449 | unsigned long addr; | |
450 | ||
451 | /* | |
452 | * might not be a highmem page, but the preempt/irq count | |
453 | * balancing is a lot nicer this way | |
454 | */ | |
455 | local_irq_save(*flags); | |
456 | addr = (unsigned long) kmap_atomic(bvec->bv_page, KM_BIO_SRC_IRQ); | |
457 | ||
458 | BUG_ON(addr & ~PAGE_MASK); | |
459 | ||
460 | return (char *) addr + bvec->bv_offset; | |
461 | } | |
462 | ||
c2d08dad | 463 | static inline void bvec_kunmap_irq(char *buffer, unsigned long *flags) |
1da177e4 LT |
464 | { |
465 | unsigned long ptr = (unsigned long) buffer & PAGE_MASK; | |
466 | ||
467 | kunmap_atomic((void *) ptr, KM_BIO_SRC_IRQ); | |
468 | local_irq_restore(*flags); | |
469 | } | |
470 | ||
471 | #else | |
472 | #define bvec_kmap_irq(bvec, flags) (page_address((bvec)->bv_page) + (bvec)->bv_offset) | |
473 | #define bvec_kunmap_irq(buf, flags) do { *(flags) = 0; } while (0) | |
474 | #endif | |
475 | ||
c2d08dad | 476 | static inline char *__bio_kmap_irq(struct bio *bio, unsigned short idx, |
1da177e4 LT |
477 | unsigned long *flags) |
478 | { | |
479 | return bvec_kmap_irq(bio_iovec_idx(bio, idx), flags); | |
480 | } | |
481 | #define __bio_kunmap_irq(buf, flags) bvec_kunmap_irq(buf, flags) | |
482 | ||
483 | #define bio_kmap_irq(bio, flags) \ | |
484 | __bio_kmap_irq((bio), (bio)->bi_idx, (flags)) | |
485 | #define bio_kunmap_irq(buf,flags) __bio_kunmap_irq(buf, flags) | |
486 | ||
7a67f63b JA |
487 | /* |
488 | * Check whether this bio carries any data or not. A NULL bio is allowed. | |
489 | */ | |
490 | static inline int bio_has_data(struct bio *bio) | |
491 | { | |
492 | return bio && bio->bi_io_vec != NULL; | |
493 | } | |
494 | ||
7ba1ba12 MP |
495 | #if defined(CONFIG_BLK_DEV_INTEGRITY) |
496 | ||
497 | #define bip_vec_idx(bip, idx) (&(bip->bip_vec[(idx)])) | |
498 | #define bip_vec(bip) bip_vec_idx(bip, 0) | |
499 | ||
500 | #define __bip_for_each_vec(bvl, bip, i, start_idx) \ | |
501 | for (bvl = bip_vec_idx((bip), (start_idx)), i = (start_idx); \ | |
502 | i < (bip)->bip_vcnt; \ | |
503 | bvl++, i++) | |
504 | ||
505 | #define bip_for_each_vec(bvl, bip, i) \ | |
506 | __bip_for_each_vec(bvl, bip, i, (bip)->bip_idx) | |
507 | ||
8deaf721 | 508 | #define bio_integrity(bio) (bio->bi_integrity != NULL) |
7ba1ba12 MP |
509 | |
510 | extern struct bio_integrity_payload *bio_integrity_alloc_bioset(struct bio *, gfp_t, unsigned int, struct bio_set *); | |
511 | extern struct bio_integrity_payload *bio_integrity_alloc(struct bio *, gfp_t, unsigned int); | |
512 | extern void bio_integrity_free(struct bio *, struct bio_set *); | |
513 | extern int bio_integrity_add_page(struct bio *, struct page *, unsigned int, unsigned int); | |
514 | extern int bio_integrity_enabled(struct bio *bio); | |
515 | extern int bio_integrity_set_tag(struct bio *, void *, unsigned int); | |
516 | extern int bio_integrity_get_tag(struct bio *, void *, unsigned int); | |
517 | extern int bio_integrity_prep(struct bio *); | |
518 | extern void bio_integrity_endio(struct bio *, int); | |
519 | extern void bio_integrity_advance(struct bio *, unsigned int); | |
520 | extern void bio_integrity_trim(struct bio *, unsigned int, unsigned int); | |
521 | extern void bio_integrity_split(struct bio *, struct bio_pair *, int); | |
522 | extern int bio_integrity_clone(struct bio *, struct bio *, struct bio_set *); | |
523 | extern int bioset_integrity_create(struct bio_set *, int); | |
524 | extern void bioset_integrity_free(struct bio_set *); | |
525 | extern void bio_integrity_init_slab(void); | |
526 | ||
527 | #else /* CONFIG_BLK_DEV_INTEGRITY */ | |
528 | ||
529 | #define bio_integrity(a) (0) | |
530 | #define bioset_integrity_create(a, b) (0) | |
531 | #define bio_integrity_prep(a) (0) | |
532 | #define bio_integrity_enabled(a) (0) | |
533 | #define bio_integrity_clone(a, b, c) (0) | |
534 | #define bioset_integrity_free(a) do { } while (0) | |
535 | #define bio_integrity_free(a, b) do { } while (0) | |
536 | #define bio_integrity_endio(a, b) do { } while (0) | |
537 | #define bio_integrity_advance(a, b) do { } while (0) | |
538 | #define bio_integrity_trim(a, b, c) do { } while (0) | |
539 | #define bio_integrity_split(a, b, c) do { } while (0) | |
540 | #define bio_integrity_set_tag(a, b, c) do { } while (0) | |
541 | #define bio_integrity_get_tag(a, b, c) do { } while (0) | |
542 | #define bio_integrity_init_slab(a) do { } while (0) | |
543 | ||
544 | #endif /* CONFIG_BLK_DEV_INTEGRITY */ | |
545 | ||
02a5e0ac | 546 | #endif /* CONFIG_BLOCK */ |
1da177e4 | 547 | #endif /* __LINUX_BIO_H */ |