| 1 | /* SPDX-License-Identifier: GPL-2.0 */ | 
|---|
| 2 | /* | 
|---|
| 3 | * Copyright (C) 2001 Jens Axboe <axboe@suse.de> | 
|---|
| 4 | */ | 
|---|
| 5 | #ifndef __LINUX_BIO_H | 
|---|
| 6 | #define __LINUX_BIO_H | 
|---|
| 7 |  | 
|---|
| 8 | #include <linux/mempool.h> | 
|---|
| 9 | /* struct bio, bio_vec and BIO_* flags are defined in blk_types.h */ | 
|---|
| 10 | #include <linux/blk_types.h> | 
|---|
| 11 | #include <linux/uio.h> | 
|---|
| 12 |  | 
|---|
| 13 | #define BIO_MAX_VECS		256U | 
|---|
| 14 | #define BIO_MAX_INLINE_VECS	UIO_MAXIOV | 
|---|
| 15 |  | 
|---|
| 16 | struct queue_limits; | 
|---|
| 17 |  | 
|---|
| 18 | static inline unsigned int bio_max_segs(unsigned int nr_segs) | 
|---|
| 19 | { | 
|---|
| 20 | return min(nr_segs, BIO_MAX_VECS); | 
|---|
| 21 | } | 
|---|
| 22 |  | 
|---|
| 23 | #define bio_iter_iovec(bio, iter)				\ | 
|---|
| 24 | bvec_iter_bvec((bio)->bi_io_vec, (iter)) | 
|---|
| 25 |  | 
|---|
| 26 | #define bio_iter_page(bio, iter)				\ | 
|---|
| 27 | bvec_iter_page((bio)->bi_io_vec, (iter)) | 
|---|
| 28 | #define bio_iter_len(bio, iter)					\ | 
|---|
| 29 | bvec_iter_len((bio)->bi_io_vec, (iter)) | 
|---|
| 30 | #define bio_iter_offset(bio, iter)				\ | 
|---|
| 31 | bvec_iter_offset((bio)->bi_io_vec, (iter)) | 
|---|
| 32 |  | 
|---|
| 33 | #define bio_page(bio)		bio_iter_page((bio), (bio)->bi_iter) | 
|---|
| 34 | #define bio_offset(bio)		bio_iter_offset((bio), (bio)->bi_iter) | 
|---|
| 35 | #define bio_iovec(bio)		bio_iter_iovec((bio), (bio)->bi_iter) | 
|---|
| 36 |  | 
|---|
| 37 | #define bvec_iter_sectors(iter)	((iter).bi_size >> 9) | 
|---|
| 38 | #define bvec_iter_end_sector(iter) ((iter).bi_sector + bvec_iter_sectors((iter))) | 
|---|
| 39 |  | 
|---|
| 40 | #define bio_sectors(bio)	bvec_iter_sectors((bio)->bi_iter) | 
|---|
| 41 | #define bio_end_sector(bio)	bvec_iter_end_sector((bio)->bi_iter) | 
|---|
| 42 |  | 
|---|
| 43 | /* | 
|---|
| 44 | * Return the data direction, READ or WRITE. | 
|---|
| 45 | */ | 
|---|
| 46 | #define bio_data_dir(bio) \ | 
|---|
| 47 | (op_is_write(bio_op(bio)) ? WRITE : READ) | 
|---|
| 48 |  | 
|---|
| 49 | /* | 
|---|
| 50 | * Check whether this bio carries any data or not. A NULL bio is allowed. | 
|---|
| 51 | */ | 
|---|
| 52 | static inline bool bio_has_data(struct bio *bio) | 
|---|
| 53 | { | 
|---|
| 54 | if (bio && | 
|---|
| 55 | bio->bi_iter.bi_size && | 
|---|
| 56 | bio_op(bio) != REQ_OP_DISCARD && | 
|---|
| 57 | bio_op(bio) != REQ_OP_SECURE_ERASE && | 
|---|
| 58 | bio_op(bio) != REQ_OP_WRITE_ZEROES) | 
|---|
| 59 | return true; | 
|---|
| 60 |  | 
|---|
| 61 | return false; | 
|---|
| 62 | } | 
|---|
| 63 |  | 
|---|
| 64 | static inline bool bio_no_advance_iter(const struct bio *bio) | 
|---|
| 65 | { | 
|---|
| 66 | return bio_op(bio) == REQ_OP_DISCARD || | 
|---|
| 67 | bio_op(bio) == REQ_OP_SECURE_ERASE || | 
|---|
| 68 | bio_op(bio) == REQ_OP_WRITE_ZEROES; | 
|---|
| 69 | } | 
|---|
| 70 |  | 
|---|
| 71 | static inline void *bio_data(struct bio *bio) | 
|---|
| 72 | { | 
|---|
| 73 | if (bio_has_data(bio)) | 
|---|
| 74 | return page_address(bio_page(bio)) + bio_offset(bio); | 
|---|
| 75 |  | 
|---|
| 76 | return NULL; | 
|---|
| 77 | } | 
|---|
| 78 |  | 
|---|
| 79 | static inline bool bio_next_segment(const struct bio *bio, | 
|---|
| 80 | struct bvec_iter_all *iter) | 
|---|
| 81 | { | 
|---|
| 82 | if (iter->idx >= bio->bi_vcnt) | 
|---|
| 83 | return false; | 
|---|
| 84 |  | 
|---|
| 85 | bvec_advance(bvec: &bio->bi_io_vec[iter->idx], iter_all: iter); | 
|---|
| 86 | return true; | 
|---|
| 87 | } | 
|---|
| 88 |  | 
|---|
| 89 | /* | 
|---|
| 90 | * drivers should _never_ use the all version - the bio may have been split | 
|---|
| 91 | * before it got to the driver and the driver won't own all of it | 
|---|
| 92 | */ | 
|---|
| 93 | #define bio_for_each_segment_all(bvl, bio, iter) \ | 
|---|
| 94 | for (bvl = bvec_init_iter_all(&iter); bio_next_segment((bio), &iter); ) | 
|---|
| 95 |  | 
|---|
| 96 | static inline void bio_advance_iter(const struct bio *bio, | 
|---|
| 97 | struct bvec_iter *iter, unsigned int bytes) | 
|---|
| 98 | { | 
|---|
| 99 | iter->bi_sector += bytes >> 9; | 
|---|
| 100 |  | 
|---|
| 101 | if (bio_no_advance_iter(bio)) | 
|---|
| 102 | iter->bi_size -= bytes; | 
|---|
| 103 | else | 
|---|
| 104 | bvec_iter_advance(bv: bio->bi_io_vec, iter, bytes); | 
|---|
| 105 | /* TODO: It is reasonable to complete bio with error here. */ | 
|---|
| 106 | } | 
|---|
| 107 |  | 
|---|
| 108 | /* @bytes should be less or equal to bvec[i->bi_idx].bv_len */ | 
|---|
| 109 | static inline void bio_advance_iter_single(const struct bio *bio, | 
|---|
| 110 | struct bvec_iter *iter, | 
|---|
| 111 | unsigned int bytes) | 
|---|
| 112 | { | 
|---|
| 113 | iter->bi_sector += bytes >> 9; | 
|---|
| 114 |  | 
|---|
| 115 | if (bio_no_advance_iter(bio)) | 
|---|
| 116 | iter->bi_size -= bytes; | 
|---|
| 117 | else | 
|---|
| 118 | bvec_iter_advance_single(bv: bio->bi_io_vec, iter, bytes); | 
|---|
| 119 | } | 
|---|
| 120 |  | 
|---|
| 121 | void __bio_advance(struct bio *, unsigned bytes); | 
|---|
| 122 |  | 
|---|
| 123 | /** | 
|---|
| 124 | * bio_advance - increment/complete a bio by some number of bytes | 
|---|
| 125 | * @bio:	bio to advance | 
|---|
| 126 | * @nbytes:	number of bytes to complete | 
|---|
| 127 | * | 
|---|
| 128 | * This updates bi_sector, bi_size and bi_idx; if the number of bytes to | 
|---|
| 129 | * complete doesn't align with a bvec boundary, then bv_len and bv_offset will | 
|---|
| 130 | * be updated on the last bvec as well. | 
|---|
| 131 | * | 
|---|
| 132 | * @bio will then represent the remaining, uncompleted portion of the io. | 
|---|
| 133 | */ | 
|---|
| 134 | static inline void bio_advance(struct bio *bio, unsigned int nbytes) | 
|---|
| 135 | { | 
|---|
| 136 | if (nbytes == bio->bi_iter.bi_size) { | 
|---|
| 137 | bio->bi_iter.bi_size = 0; | 
|---|
| 138 | return; | 
|---|
| 139 | } | 
|---|
| 140 | __bio_advance(bio, bytes: nbytes); | 
|---|
| 141 | } | 
|---|
| 142 |  | 
|---|
| 143 | #define __bio_for_each_segment(bvl, bio, iter, start)			\ | 
|---|
| 144 | for (iter = (start);						\ | 
|---|
| 145 | (iter).bi_size &&						\ | 
|---|
| 146 | ((bvl = bio_iter_iovec((bio), (iter))), 1);		\ | 
|---|
| 147 | bio_advance_iter_single((bio), &(iter), (bvl).bv_len)) | 
|---|
| 148 |  | 
|---|
| 149 | #define bio_for_each_segment(bvl, bio, iter)				\ | 
|---|
| 150 | __bio_for_each_segment(bvl, bio, iter, (bio)->bi_iter) | 
|---|
| 151 |  | 
|---|
| 152 | #define __bio_for_each_bvec(bvl, bio, iter, start)		\ | 
|---|
| 153 | for (iter = (start);						\ | 
|---|
| 154 | (iter).bi_size &&						\ | 
|---|
| 155 | ((bvl = mp_bvec_iter_bvec((bio)->bi_io_vec, (iter))), 1); \ | 
|---|
| 156 | bio_advance_iter_single((bio), &(iter), (bvl).bv_len)) | 
|---|
| 157 |  | 
|---|
| 158 | /* iterate over multi-page bvec */ | 
|---|
| 159 | #define bio_for_each_bvec(bvl, bio, iter)			\ | 
|---|
| 160 | __bio_for_each_bvec(bvl, bio, iter, (bio)->bi_iter) | 
|---|
| 161 |  | 
|---|
| 162 | /* | 
|---|
| 163 | * Iterate over all multi-page bvecs. Drivers shouldn't use this version for the | 
|---|
| 164 | * same reasons as bio_for_each_segment_all(). | 
|---|
| 165 | */ | 
|---|
| 166 | #define bio_for_each_bvec_all(bvl, bio, i)		\ | 
|---|
| 167 | for (i = 0, bvl = bio_first_bvec_all(bio);	\ | 
|---|
| 168 | i < (bio)->bi_vcnt; i++, bvl++) | 
|---|
| 169 |  | 
|---|
| 170 | #define bio_iter_last(bvec, iter) ((iter).bi_size == (bvec).bv_len) | 
|---|
| 171 |  | 
|---|
| 172 | static inline unsigned bio_segments(struct bio *bio) | 
|---|
| 173 | { | 
|---|
| 174 | unsigned segs = 0; | 
|---|
| 175 | struct bio_vec bv; | 
|---|
| 176 | struct bvec_iter iter; | 
|---|
| 177 |  | 
|---|
| 178 | /* | 
|---|
| 179 | * We special case discard/write same/write zeroes, because they | 
|---|
| 180 | * interpret bi_size differently: | 
|---|
| 181 | */ | 
|---|
| 182 |  | 
|---|
| 183 | switch (bio_op(bio)) { | 
|---|
| 184 | case REQ_OP_DISCARD: | 
|---|
| 185 | case REQ_OP_SECURE_ERASE: | 
|---|
| 186 | case REQ_OP_WRITE_ZEROES: | 
|---|
| 187 | return 0; | 
|---|
| 188 | default: | 
|---|
| 189 | break; | 
|---|
| 190 | } | 
|---|
| 191 |  | 
|---|
| 192 | bio_for_each_segment(bv, bio, iter) | 
|---|
| 193 | segs++; | 
|---|
| 194 |  | 
|---|
| 195 | return segs; | 
|---|
| 196 | } | 
|---|
| 197 |  | 
|---|
| 198 | /* | 
|---|
| 199 | * get a reference to a bio, so it won't disappear. the intended use is | 
|---|
| 200 | * something like: | 
|---|
| 201 | * | 
|---|
| 202 | * bio_get(bio); | 
|---|
| 203 | * submit_bio(rw, bio); | 
|---|
| 204 | * if (bio->bi_flags ...) | 
|---|
| 205 | *	do_something | 
|---|
| 206 | * bio_put(bio); | 
|---|
| 207 | * | 
|---|
| 208 | * without the bio_get(), it could potentially complete I/O before submit_bio | 
|---|
| 209 | * returns. and then bio would be freed memory when if (bio->bi_flags ...) | 
|---|
| 210 | * runs | 
|---|
| 211 | */ | 
|---|
| 212 | static inline void bio_get(struct bio *bio) | 
|---|
| 213 | { | 
|---|
| 214 | bio->bi_flags |= (1 << BIO_REFFED); | 
|---|
| 215 | smp_mb__before_atomic(); | 
|---|
| 216 | atomic_inc(v: &bio->__bi_cnt); | 
|---|
| 217 | } | 
|---|
| 218 |  | 
|---|
| 219 | static inline void bio_cnt_set(struct bio *bio, unsigned int count) | 
|---|
| 220 | { | 
|---|
| 221 | if (count != 1) { | 
|---|
| 222 | bio->bi_flags |= (1 << BIO_REFFED); | 
|---|
| 223 | smp_mb(); | 
|---|
| 224 | } | 
|---|
| 225 | atomic_set(v: &bio->__bi_cnt, i: count); | 
|---|
| 226 | } | 
|---|
| 227 |  | 
|---|
| 228 | static inline bool bio_flagged(struct bio *bio, unsigned int bit) | 
|---|
| 229 | { | 
|---|
| 230 | return bio->bi_flags & (1U << bit); | 
|---|
| 231 | } | 
|---|
| 232 |  | 
|---|
| 233 | static inline void bio_set_flag(struct bio *bio, unsigned int bit) | 
|---|
| 234 | { | 
|---|
| 235 | bio->bi_flags |= (1U << bit); | 
|---|
| 236 | } | 
|---|
| 237 |  | 
|---|
| 238 | static inline void bio_clear_flag(struct bio *bio, unsigned int bit) | 
|---|
| 239 | { | 
|---|
| 240 | bio->bi_flags &= ~(1U << bit); | 
|---|
| 241 | } | 
|---|
| 242 |  | 
|---|
| 243 | static inline struct bio_vec *bio_first_bvec_all(struct bio *bio) | 
|---|
| 244 | { | 
|---|
| 245 | WARN_ON_ONCE(bio_flagged(bio, BIO_CLONED)); | 
|---|
| 246 | return bio->bi_io_vec; | 
|---|
| 247 | } | 
|---|
| 248 |  | 
|---|
| 249 | static inline struct page *bio_first_page_all(struct bio *bio) | 
|---|
| 250 | { | 
|---|
| 251 | return bio_first_bvec_all(bio)->bv_page; | 
|---|
| 252 | } | 
|---|
| 253 |  | 
|---|
| 254 | static inline struct folio *bio_first_folio_all(struct bio *bio) | 
|---|
| 255 | { | 
|---|
| 256 | return page_folio(bio_first_page_all(bio)); | 
|---|
| 257 | } | 
|---|
| 258 |  | 
|---|
| 259 | static inline struct bio_vec *bio_last_bvec_all(struct bio *bio) | 
|---|
| 260 | { | 
|---|
| 261 | WARN_ON_ONCE(bio_flagged(bio, BIO_CLONED)); | 
|---|
| 262 | return &bio->bi_io_vec[bio->bi_vcnt - 1]; | 
|---|
| 263 | } | 
|---|
| 264 |  | 
|---|
| 265 | /** | 
|---|
| 266 | * struct folio_iter - State for iterating all folios in a bio. | 
|---|
| 267 | * @folio: The current folio we're iterating.  NULL after the last folio. | 
|---|
| 268 | * @offset: The byte offset within the current folio. | 
|---|
| 269 | * @length: The number of bytes in this iteration (will not cross folio | 
|---|
| 270 | *	boundary). | 
|---|
| 271 | */ | 
|---|
| 272 | struct folio_iter { | 
|---|
| 273 | struct folio *folio; | 
|---|
| 274 | size_t offset; | 
|---|
| 275 | size_t length; | 
|---|
| 276 | /* private: for use by the iterator */ | 
|---|
| 277 | struct folio *_next; | 
|---|
| 278 | size_t _seg_count; | 
|---|
| 279 | int _i; | 
|---|
| 280 | }; | 
|---|
| 281 |  | 
|---|
| 282 | static inline void bio_first_folio(struct folio_iter *fi, struct bio *bio, | 
|---|
| 283 | int i) | 
|---|
| 284 | { | 
|---|
| 285 | struct bio_vec *bvec = bio_first_bvec_all(bio) + i; | 
|---|
| 286 |  | 
|---|
| 287 | if (unlikely(i >= bio->bi_vcnt)) { | 
|---|
| 288 | fi->folio = NULL; | 
|---|
| 289 | return; | 
|---|
| 290 | } | 
|---|
| 291 |  | 
|---|
| 292 | fi->folio = page_folio(bvec->bv_page); | 
|---|
| 293 | fi->offset = bvec->bv_offset + | 
|---|
| 294 | PAGE_SIZE * folio_page_idx(folio: fi->folio, page: bvec->bv_page); | 
|---|
| 295 | fi->_seg_count = bvec->bv_len; | 
|---|
| 296 | fi->length = min(folio_size(fi->folio) - fi->offset, fi->_seg_count); | 
|---|
| 297 | fi->_next = folio_next(folio: fi->folio); | 
|---|
| 298 | fi->_i = i; | 
|---|
| 299 | } | 
|---|
| 300 |  | 
|---|
| 301 | static inline void bio_next_folio(struct folio_iter *fi, struct bio *bio) | 
|---|
| 302 | { | 
|---|
| 303 | fi->_seg_count -= fi->length; | 
|---|
| 304 | if (fi->_seg_count) { | 
|---|
| 305 | fi->folio = fi->_next; | 
|---|
| 306 | fi->offset = 0; | 
|---|
| 307 | fi->length = min(folio_size(fi->folio), fi->_seg_count); | 
|---|
| 308 | fi->_next = folio_next(folio: fi->folio); | 
|---|
| 309 | } else { | 
|---|
| 310 | bio_first_folio(fi, bio, i: fi->_i + 1); | 
|---|
| 311 | } | 
|---|
| 312 | } | 
|---|
| 313 |  | 
|---|
| 314 | /** | 
|---|
| 315 | * bio_for_each_folio_all - Iterate over each folio in a bio. | 
|---|
| 316 | * @fi: struct folio_iter which is updated for each folio. | 
|---|
| 317 | * @bio: struct bio to iterate over. | 
|---|
| 318 | */ | 
|---|
| 319 | #define bio_for_each_folio_all(fi, bio)				\ | 
|---|
| 320 | for (bio_first_folio(&fi, bio, 0); fi.folio; bio_next_folio(&fi, bio)) | 
|---|
| 321 |  | 
|---|
| 322 | void bio_trim(struct bio *bio, sector_t offset, sector_t size); | 
|---|
| 323 | extern struct bio *bio_split(struct bio *bio, int sectors, | 
|---|
| 324 | gfp_t gfp, struct bio_set *bs); | 
|---|
| 325 | int bio_split_io_at(struct bio *bio, const struct queue_limits *lim, | 
|---|
| 326 | unsigned *segs, unsigned max_bytes, unsigned len_align); | 
|---|
| 327 |  | 
|---|
| 328 | /** | 
|---|
| 329 | * bio_next_split - get next @sectors from a bio, splitting if necessary | 
|---|
| 330 | * @bio:	bio to split | 
|---|
| 331 | * @sectors:	number of sectors to split from the front of @bio | 
|---|
| 332 | * @gfp:	gfp mask | 
|---|
| 333 | * @bs:		bio set to allocate from | 
|---|
| 334 | * | 
|---|
| 335 | * Return: a bio representing the next @sectors of @bio - if the bio is smaller | 
|---|
| 336 | * than @sectors, returns the original bio unchanged. | 
|---|
| 337 | */ | 
|---|
| 338 | static inline struct bio *bio_next_split(struct bio *bio, int sectors, | 
|---|
| 339 | gfp_t gfp, struct bio_set *bs) | 
|---|
| 340 | { | 
|---|
| 341 | if (sectors >= bio_sectors(bio)) | 
|---|
| 342 | return bio; | 
|---|
| 343 |  | 
|---|
| 344 | return bio_split(bio, sectors, gfp, bs); | 
|---|
| 345 | } | 
|---|
| 346 |  | 
|---|
| 347 | enum { | 
|---|
| 348 | BIOSET_NEED_BVECS = BIT(0), | 
|---|
| 349 | BIOSET_NEED_RESCUER = BIT(1), | 
|---|
| 350 | BIOSET_PERCPU_CACHE = BIT(2), | 
|---|
| 351 | }; | 
|---|
| 352 | extern int bioset_init(struct bio_set *, unsigned int, unsigned int, int flags); | 
|---|
| 353 | extern void bioset_exit(struct bio_set *); | 
|---|
| 354 | extern int biovec_init_pool(mempool_t *pool, int pool_entries); | 
|---|
| 355 |  | 
|---|
| 356 | struct bio *bio_alloc_bioset(struct block_device *bdev, unsigned short nr_vecs, | 
|---|
| 357 | blk_opf_t opf, gfp_t gfp_mask, | 
|---|
| 358 | struct bio_set *bs); | 
|---|
| 359 | struct bio *bio_kmalloc(unsigned short nr_vecs, gfp_t gfp_mask); | 
|---|
| 360 | extern void bio_put(struct bio *); | 
|---|
| 361 |  | 
|---|
| 362 | struct bio *bio_alloc_clone(struct block_device *bdev, struct bio *bio_src, | 
|---|
| 363 | gfp_t gfp, struct bio_set *bs); | 
|---|
| 364 | int bio_init_clone(struct block_device *bdev, struct bio *bio, | 
|---|
| 365 | struct bio *bio_src, gfp_t gfp); | 
|---|
| 366 |  | 
|---|
| 367 | extern struct bio_set fs_bio_set; | 
|---|
| 368 |  | 
|---|
| 369 | static inline struct bio *bio_alloc(struct block_device *bdev, | 
|---|
| 370 | unsigned short nr_vecs, blk_opf_t opf, gfp_t gfp_mask) | 
|---|
| 371 | { | 
|---|
| 372 | return bio_alloc_bioset(bdev, nr_vecs, opf, gfp_mask, bs: &fs_bio_set); | 
|---|
| 373 | } | 
|---|
| 374 |  | 
|---|
| 375 | void submit_bio(struct bio *bio); | 
|---|
| 376 |  | 
|---|
| 377 | extern void bio_endio(struct bio *); | 
|---|
| 378 |  | 
|---|
| 379 | static inline void bio_io_error(struct bio *bio) | 
|---|
| 380 | { | 
|---|
| 381 | bio->bi_status = BLK_STS_IOERR; | 
|---|
| 382 | bio_endio(bio); | 
|---|
| 383 | } | 
|---|
| 384 |  | 
|---|
| 385 | static inline void bio_wouldblock_error(struct bio *bio) | 
|---|
| 386 | { | 
|---|
| 387 | bio_set_flag(bio, bit: BIO_QUIET); | 
|---|
| 388 | bio->bi_status = BLK_STS_AGAIN; | 
|---|
| 389 | bio_endio(bio); | 
|---|
| 390 | } | 
|---|
| 391 |  | 
|---|
| 392 | /* | 
|---|
| 393 | * Calculate number of bvec segments that should be allocated to fit data | 
|---|
| 394 | * pointed by @iter. If @iter is backed by bvec it's going to be reused | 
|---|
| 395 | * instead of allocating a new one. | 
|---|
| 396 | */ | 
|---|
| 397 | static inline int bio_iov_vecs_to_alloc(struct iov_iter *iter, int max_segs) | 
|---|
| 398 | { | 
|---|
| 399 | if (iov_iter_is_bvec(i: iter)) | 
|---|
| 400 | return 0; | 
|---|
| 401 | return iov_iter_npages(i: iter, maxpages: max_segs); | 
|---|
| 402 | } | 
|---|
| 403 |  | 
|---|
| 404 | struct request_queue; | 
|---|
| 405 |  | 
|---|
| 406 | void bio_init(struct bio *bio, struct block_device *bdev, struct bio_vec *table, | 
|---|
| 407 | unsigned short max_vecs, blk_opf_t opf); | 
|---|
| 408 | static inline void bio_init_inline(struct bio *bio, struct block_device *bdev, | 
|---|
| 409 | unsigned short max_vecs, blk_opf_t opf) | 
|---|
| 410 | { | 
|---|
| 411 | bio_init(bio, bdev, table: bio_inline_vecs(bio), max_vecs, opf); | 
|---|
| 412 | } | 
|---|
| 413 | extern void bio_uninit(struct bio *); | 
|---|
| 414 | void bio_reset(struct bio *bio, struct block_device *bdev, blk_opf_t opf); | 
|---|
| 415 | void bio_chain(struct bio *, struct bio *); | 
|---|
| 416 |  | 
|---|
| 417 | int __must_check bio_add_page(struct bio *bio, struct page *page, unsigned len, | 
|---|
| 418 | unsigned off); | 
|---|
| 419 | bool __must_check bio_add_folio(struct bio *bio, struct folio *folio, | 
|---|
| 420 | size_t len, size_t off); | 
|---|
| 421 | void __bio_add_page(struct bio *bio, struct page *page, | 
|---|
| 422 | unsigned int len, unsigned int off); | 
|---|
| 423 | void bio_add_folio_nofail(struct bio *bio, struct folio *folio, size_t len, | 
|---|
| 424 | size_t off); | 
|---|
| 425 | void bio_add_virt_nofail(struct bio *bio, void *vaddr, unsigned len); | 
|---|
| 426 |  | 
|---|
| 427 | /** | 
|---|
| 428 | * bio_add_max_vecs - number of bio_vecs needed to add data to a bio | 
|---|
| 429 | * @kaddr: kernel virtual address to add | 
|---|
| 430 | * @len: length in bytes to add | 
|---|
| 431 | * | 
|---|
| 432 | * Calculate how many bio_vecs need to be allocated to add the kernel virtual | 
|---|
| 433 | * address range in [@kaddr:@len] in the worse case. | 
|---|
| 434 | */ | 
|---|
| 435 | static inline unsigned int bio_add_max_vecs(void *kaddr, unsigned int len) | 
|---|
| 436 | { | 
|---|
| 437 | if (is_vmalloc_addr(x: kaddr)) | 
|---|
| 438 | return DIV_ROUND_UP(offset_in_page(kaddr) + len, PAGE_SIZE); | 
|---|
| 439 | return 1; | 
|---|
| 440 | } | 
|---|
| 441 |  | 
|---|
| 442 | unsigned int bio_add_vmalloc_chunk(struct bio *bio, void *vaddr, unsigned len); | 
|---|
| 443 | bool bio_add_vmalloc(struct bio *bio, void *vaddr, unsigned int len); | 
|---|
| 444 |  | 
|---|
| 445 | int submit_bio_wait(struct bio *bio); | 
|---|
| 446 | int bdev_rw_virt(struct block_device *bdev, sector_t sector, void *data, | 
|---|
| 447 | size_t len, enum req_op op); | 
|---|
| 448 |  | 
|---|
| 449 | int bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter, | 
|---|
| 450 | unsigned len_align_mask); | 
|---|
| 451 |  | 
|---|
| 452 | void bio_iov_bvec_set(struct bio *bio, const struct iov_iter *iter); | 
|---|
| 453 | void __bio_release_pages(struct bio *bio, bool mark_dirty); | 
|---|
| 454 | extern void bio_set_pages_dirty(struct bio *bio); | 
|---|
| 455 | extern void bio_check_pages_dirty(struct bio *bio); | 
|---|
| 456 |  | 
|---|
| 457 | extern void bio_copy_data_iter(struct bio *dst, struct bvec_iter *dst_iter, | 
|---|
| 458 | struct bio *src, struct bvec_iter *src_iter); | 
|---|
| 459 | extern void bio_copy_data(struct bio *dst, struct bio *src); | 
|---|
| 460 | extern void bio_free_pages(struct bio *bio); | 
|---|
| 461 | void guard_bio_eod(struct bio *bio); | 
|---|
| 462 | void zero_fill_bio_iter(struct bio *bio, struct bvec_iter iter); | 
|---|
| 463 |  | 
|---|
| 464 | static inline void zero_fill_bio(struct bio *bio) | 
|---|
| 465 | { | 
|---|
| 466 | zero_fill_bio_iter(bio, iter: bio->bi_iter); | 
|---|
| 467 | } | 
|---|
| 468 |  | 
|---|
| 469 | static inline void bio_release_pages(struct bio *bio, bool mark_dirty) | 
|---|
| 470 | { | 
|---|
| 471 | if (bio_flagged(bio, bit: BIO_PAGE_PINNED)) | 
|---|
| 472 | __bio_release_pages(bio, mark_dirty); | 
|---|
| 473 | } | 
|---|
| 474 |  | 
|---|
| 475 | #define bio_dev(bio) \ | 
|---|
| 476 | disk_devt((bio)->bi_bdev->bd_disk) | 
|---|
| 477 |  | 
|---|
| 478 | #ifdef CONFIG_BLK_CGROUP | 
|---|
| 479 | void bio_associate_blkg(struct bio *bio); | 
|---|
| 480 | void bio_associate_blkg_from_css(struct bio *bio, | 
|---|
| 481 | struct cgroup_subsys_state *css); | 
|---|
| 482 | void bio_clone_blkg_association(struct bio *dst, struct bio *src); | 
|---|
| 483 | void blkcg_punt_bio_submit(struct bio *bio); | 
|---|
| 484 | #else	/* CONFIG_BLK_CGROUP */ | 
|---|
| 485 | static inline void bio_associate_blkg(struct bio *bio) { } | 
|---|
| 486 | static inline void bio_associate_blkg_from_css(struct bio *bio, | 
|---|
| 487 | struct cgroup_subsys_state *css) | 
|---|
| 488 | { } | 
|---|
| 489 | static inline void bio_clone_blkg_association(struct bio *dst, | 
|---|
| 490 | struct bio *src) { } | 
|---|
| 491 | static inline void blkcg_punt_bio_submit(struct bio *bio) | 
|---|
| 492 | { | 
|---|
| 493 | submit_bio(bio); | 
|---|
| 494 | } | 
|---|
| 495 | #endif	/* CONFIG_BLK_CGROUP */ | 
|---|
| 496 |  | 
|---|
| 497 | static inline void bio_set_dev(struct bio *bio, struct block_device *bdev) | 
|---|
| 498 | { | 
|---|
| 499 | bio_clear_flag(bio, bit: BIO_REMAPPED); | 
|---|
| 500 | if (bio->bi_bdev != bdev) | 
|---|
| 501 | bio_clear_flag(bio, bit: BIO_BPS_THROTTLED); | 
|---|
| 502 | bio->bi_bdev = bdev; | 
|---|
| 503 | bio_associate_blkg(bio); | 
|---|
| 504 | } | 
|---|
| 505 |  | 
|---|
| 506 | /* | 
|---|
| 507 | * BIO list management for use by remapping drivers (e.g. DM or MD) and loop. | 
|---|
| 508 | * | 
|---|
| 509 | * A bio_list anchors a singly-linked list of bios chained through the bi_next | 
|---|
| 510 | * member of the bio.  The bio_list also caches the last list member to allow | 
|---|
| 511 | * fast access to the tail. | 
|---|
| 512 | */ | 
|---|
| 513 | struct bio_list { | 
|---|
| 514 | struct bio *head; | 
|---|
| 515 | struct bio *tail; | 
|---|
| 516 | }; | 
|---|
| 517 |  | 
|---|
| 518 | static inline int bio_list_empty(const struct bio_list *bl) | 
|---|
| 519 | { | 
|---|
| 520 | return bl->head == NULL; | 
|---|
| 521 | } | 
|---|
| 522 |  | 
|---|
| 523 | static inline void bio_list_init(struct bio_list *bl) | 
|---|
| 524 | { | 
|---|
| 525 | bl->head = bl->tail = NULL; | 
|---|
| 526 | } | 
|---|
| 527 |  | 
|---|
| 528 | #define BIO_EMPTY_LIST	{ NULL, NULL } | 
|---|
| 529 |  | 
|---|
| 530 | #define bio_list_for_each(bio, bl) \ | 
|---|
| 531 | for (bio = (bl)->head; bio; bio = bio->bi_next) | 
|---|
| 532 |  | 
|---|
| 533 | static inline unsigned bio_list_size(const struct bio_list *bl) | 
|---|
| 534 | { | 
|---|
| 535 | unsigned sz = 0; | 
|---|
| 536 | struct bio *bio; | 
|---|
| 537 |  | 
|---|
| 538 | bio_list_for_each(bio, bl) | 
|---|
| 539 | sz++; | 
|---|
| 540 |  | 
|---|
| 541 | return sz; | 
|---|
| 542 | } | 
|---|
| 543 |  | 
|---|
| 544 | static inline void bio_list_add(struct bio_list *bl, struct bio *bio) | 
|---|
| 545 | { | 
|---|
| 546 | bio->bi_next = NULL; | 
|---|
| 547 |  | 
|---|
| 548 | if (bl->tail) | 
|---|
| 549 | bl->tail->bi_next = bio; | 
|---|
| 550 | else | 
|---|
| 551 | bl->head = bio; | 
|---|
| 552 |  | 
|---|
| 553 | bl->tail = bio; | 
|---|
| 554 | } | 
|---|
| 555 |  | 
|---|
| 556 | static inline void bio_list_add_head(struct bio_list *bl, struct bio *bio) | 
|---|
| 557 | { | 
|---|
| 558 | bio->bi_next = bl->head; | 
|---|
| 559 |  | 
|---|
| 560 | bl->head = bio; | 
|---|
| 561 |  | 
|---|
| 562 | if (!bl->tail) | 
|---|
| 563 | bl->tail = bio; | 
|---|
| 564 | } | 
|---|
| 565 |  | 
|---|
| 566 | static inline void bio_list_merge(struct bio_list *bl, struct bio_list *bl2) | 
|---|
| 567 | { | 
|---|
| 568 | if (!bl2->head) | 
|---|
| 569 | return; | 
|---|
| 570 |  | 
|---|
| 571 | if (bl->tail) | 
|---|
| 572 | bl->tail->bi_next = bl2->head; | 
|---|
| 573 | else | 
|---|
| 574 | bl->head = bl2->head; | 
|---|
| 575 |  | 
|---|
| 576 | bl->tail = bl2->tail; | 
|---|
| 577 | } | 
|---|
| 578 |  | 
|---|
| 579 | static inline void bio_list_merge_init(struct bio_list *bl, | 
|---|
| 580 | struct bio_list *bl2) | 
|---|
| 581 | { | 
|---|
| 582 | bio_list_merge(bl, bl2); | 
|---|
| 583 | bio_list_init(bl: bl2); | 
|---|
| 584 | } | 
|---|
| 585 |  | 
|---|
| 586 | static inline void bio_list_merge_head(struct bio_list *bl, | 
|---|
| 587 | struct bio_list *bl2) | 
|---|
| 588 | { | 
|---|
| 589 | if (!bl2->head) | 
|---|
| 590 | return; | 
|---|
| 591 |  | 
|---|
| 592 | if (bl->head) | 
|---|
| 593 | bl2->tail->bi_next = bl->head; | 
|---|
| 594 | else | 
|---|
| 595 | bl->tail = bl2->tail; | 
|---|
| 596 |  | 
|---|
| 597 | bl->head = bl2->head; | 
|---|
| 598 | } | 
|---|
| 599 |  | 
|---|
| 600 | static inline struct bio *bio_list_peek(struct bio_list *bl) | 
|---|
| 601 | { | 
|---|
| 602 | return bl->head; | 
|---|
| 603 | } | 
|---|
| 604 |  | 
|---|
| 605 | static inline struct bio *bio_list_pop(struct bio_list *bl) | 
|---|
| 606 | { | 
|---|
| 607 | struct bio *bio = bl->head; | 
|---|
| 608 |  | 
|---|
| 609 | if (bio) { | 
|---|
| 610 | bl->head = bl->head->bi_next; | 
|---|
| 611 | if (!bl->head) | 
|---|
| 612 | bl->tail = NULL; | 
|---|
| 613 |  | 
|---|
| 614 | bio->bi_next = NULL; | 
|---|
| 615 | } | 
|---|
| 616 |  | 
|---|
| 617 | return bio; | 
|---|
| 618 | } | 
|---|
| 619 |  | 
|---|
| 620 | static inline struct bio *bio_list_get(struct bio_list *bl) | 
|---|
| 621 | { | 
|---|
| 622 | struct bio *bio = bl->head; | 
|---|
| 623 |  | 
|---|
| 624 | bl->head = bl->tail = NULL; | 
|---|
| 625 |  | 
|---|
| 626 | return bio; | 
|---|
| 627 | } | 
|---|
| 628 |  | 
|---|
| 629 | /* | 
|---|
| 630 | * Increment chain count for the bio. Make sure the CHAIN flag update | 
|---|
| 631 | * is visible before the raised count. | 
|---|
| 632 | */ | 
|---|
| 633 | static inline void bio_inc_remaining(struct bio *bio) | 
|---|
| 634 | { | 
|---|
| 635 | bio_set_flag(bio, bit: BIO_CHAIN); | 
|---|
| 636 | smp_mb__before_atomic(); | 
|---|
| 637 | atomic_inc(v: &bio->__bi_remaining); | 
|---|
| 638 | } | 
|---|
| 639 |  | 
|---|
| 640 | /* | 
|---|
| 641 | * bio_set is used to allow other portions of the IO system to | 
|---|
| 642 | * allocate their own private memory pools for bio and iovec structures. | 
|---|
| 643 | * These memory pools in turn all allocate from the bio_slab | 
|---|
| 644 | * and the bvec_slabs[]. | 
|---|
| 645 | */ | 
|---|
| 646 | #define BIO_POOL_SIZE 2 | 
|---|
| 647 |  | 
|---|
| 648 | struct bio_set { | 
|---|
| 649 | struct kmem_cache *bio_slab; | 
|---|
| 650 | unsigned int front_pad; | 
|---|
| 651 |  | 
|---|
| 652 | /* | 
|---|
| 653 | * per-cpu bio alloc cache | 
|---|
| 654 | */ | 
|---|
| 655 | struct bio_alloc_cache __percpu *cache; | 
|---|
| 656 |  | 
|---|
| 657 | mempool_t bio_pool; | 
|---|
| 658 | mempool_t bvec_pool; | 
|---|
| 659 |  | 
|---|
| 660 | unsigned int back_pad; | 
|---|
| 661 | /* | 
|---|
| 662 | * Deadlock avoidance for stacking block drivers: see comments in | 
|---|
| 663 | * bio_alloc_bioset() for details | 
|---|
| 664 | */ | 
|---|
| 665 | spinlock_t		rescue_lock; | 
|---|
| 666 | struct bio_list		rescue_list; | 
|---|
| 667 | struct work_struct	rescue_work; | 
|---|
| 668 | struct workqueue_struct	*rescue_workqueue; | 
|---|
| 669 |  | 
|---|
| 670 | /* | 
|---|
| 671 | * Hot un-plug notifier for the per-cpu cache, if used | 
|---|
| 672 | */ | 
|---|
| 673 | struct hlist_node cpuhp_dead; | 
|---|
| 674 | }; | 
|---|
| 675 |  | 
|---|
| 676 | static inline bool bioset_initialized(struct bio_set *bs) | 
|---|
| 677 | { | 
|---|
| 678 | return bs->bio_slab != NULL; | 
|---|
| 679 | } | 
|---|
| 680 |  | 
|---|
| 681 | /* | 
|---|
| 682 | * Mark a bio as polled. Note that for async polled IO, the caller must | 
|---|
| 683 | * expect -EWOULDBLOCK if we cannot allocate a request (or other resources). | 
|---|
| 684 | * We cannot block waiting for requests on polled IO, as those completions | 
|---|
| 685 | * must be found by the caller. This is different than IRQ driven IO, where | 
|---|
| 686 | * it's safe to wait for IO to complete. | 
|---|
| 687 | */ | 
|---|
| 688 | static inline void bio_set_polled(struct bio *bio, struct kiocb *kiocb) | 
|---|
| 689 | { | 
|---|
| 690 | bio->bi_opf |= REQ_POLLED; | 
|---|
| 691 | if (kiocb->ki_flags & IOCB_NOWAIT) | 
|---|
| 692 | bio->bi_opf |= REQ_NOWAIT; | 
|---|
| 693 | } | 
|---|
| 694 |  | 
|---|
| 695 | static inline void bio_clear_polled(struct bio *bio) | 
|---|
| 696 | { | 
|---|
| 697 | bio->bi_opf &= ~REQ_POLLED; | 
|---|
| 698 | } | 
|---|
| 699 |  | 
|---|
| 700 | /** | 
|---|
| 701 | * bio_is_zone_append - is this a zone append bio? | 
|---|
| 702 | * @bio:	bio to check | 
|---|
| 703 | * | 
|---|
| 704 | * Check if @bio is a zone append operation.  Core block layer code and end_io | 
|---|
| 705 | * handlers must use this instead of an open coded REQ_OP_ZONE_APPEND check | 
|---|
| 706 | * because the block layer can rewrite REQ_OP_ZONE_APPEND to REQ_OP_WRITE if | 
|---|
| 707 | * it is not natively supported. | 
|---|
| 708 | */ | 
|---|
| 709 | static inline bool bio_is_zone_append(struct bio *bio) | 
|---|
| 710 | { | 
|---|
| 711 | if (!IS_ENABLED(CONFIG_BLK_DEV_ZONED)) | 
|---|
| 712 | return false; | 
|---|
| 713 | return bio_op(bio) == REQ_OP_ZONE_APPEND || | 
|---|
| 714 | bio_flagged(bio, bit: BIO_EMULATES_ZONE_APPEND); | 
|---|
| 715 | } | 
|---|
| 716 |  | 
|---|
| 717 | struct bio *blk_next_bio(struct bio *bio, struct block_device *bdev, | 
|---|
| 718 | unsigned int nr_pages, blk_opf_t opf, gfp_t gfp); | 
|---|
| 719 | struct bio *bio_chain_and_submit(struct bio *prev, struct bio *new); | 
|---|
| 720 |  | 
|---|
| 721 | struct bio *blk_alloc_discard_bio(struct block_device *bdev, | 
|---|
| 722 | sector_t *sector, sector_t *nr_sects, gfp_t gfp_mask); | 
|---|
| 723 |  | 
|---|
| 724 | #endif /* __LINUX_BIO_H */ | 
|---|
| 725 |  | 
|---|