1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3 * Block data types and constants. Directly include this file only to
4 * break include dependency loop.
5 */
6 #ifndef __LINUX_BLK_TYPES_H
7 #define __LINUX_BLK_TYPES_H
8
9 #include <linux/types.h>
10 #include <linux/bvec.h>
11 #include <linux/device.h>
12 #include <linux/ktime.h>
13 #include <linux/rw_hint.h>
14 #include <linux/android_kabi.h>
15
16 struct bio_set;
17 struct bio;
18 struct bio_integrity_payload;
19 struct page;
20 struct io_context;
21 struct cgroup_subsys_state;
22 typedef void (bio_end_io_t) (struct bio *);
23 struct bio_crypt_ctx;
24
25 /*
26 * The basic unit of block I/O is a sector. It is used in a number of contexts
27 * in Linux (blk, bio, genhd). The size of one sector is 512 = 2**9
28 * bytes. Variables of type sector_t represent an offset or size that is a
29 * multiple of 512 bytes. Hence these two constants.
30 */
31 #ifndef SECTOR_SHIFT
32 #define SECTOR_SHIFT 9
33 #endif
34 #ifndef SECTOR_SIZE
35 #define SECTOR_SIZE (1 << SECTOR_SHIFT)
36 #endif
37
38 #define PAGE_SECTORS_SHIFT (PAGE_SHIFT - SECTOR_SHIFT)
39 #define PAGE_SECTORS (1 << PAGE_SECTORS_SHIFT)
40 #define SECTOR_MASK (PAGE_SECTORS - 1)
41
42 struct block_device {
43 sector_t bd_start_sect;
44 sector_t bd_nr_sectors;
45 struct gendisk * bd_disk;
46 struct request_queue * bd_queue;
47 struct disk_stats __percpu *bd_stats;
48 unsigned long bd_stamp;
49 bool bd_read_only; /* read-only policy */
50 u8 bd_partno;
51 bool bd_write_holder;
52 bool bd_has_submit_bio;
53 dev_t bd_dev;
54 atomic_t bd_openers;
55 spinlock_t bd_size_lock; /* for bd_inode->i_size updates */
56 struct inode * bd_inode; /* will die */
57 void * bd_claiming;
58 void * bd_holder;
59 const struct blk_holder_ops *bd_holder_ops;
60 struct mutex bd_holder_lock;
61 /* The counter of freeze processes */
62 int bd_fsfreeze_count;
63 int bd_holders;
64 struct kobject *bd_holder_dir;
65
66 /* Mutex for freeze */
67 struct mutex bd_fsfreeze_mutex;
68 struct super_block *bd_fsfreeze_sb;
69
70 struct partition_meta_info *bd_meta_info;
71 #ifdef CONFIG_FAIL_MAKE_REQUEST
72 bool bd_make_it_fail;
73 #endif
74 bool bd_ro_warned;
75 /*
76 * keep this out-of-line as it's both big and not needed in the fast
77 * path
78 */
79 struct device bd_device;
80 } __randomize_layout;
81
82 #define bdev_whole(_bdev) \
83 ((_bdev)->bd_disk->part0)
84
85 #define dev_to_bdev(device) \
86 container_of((device), struct block_device, bd_device)
87
88 #define bdev_kobj(_bdev) \
89 (&((_bdev)->bd_device.kobj))
90
91 /*
92 * Block error status values. See block/blk-core:blk_errors for the details.
93 * Alpha cannot write a byte atomically, so we need to use 32-bit value.
94 */
95 #if defined(CONFIG_ALPHA) && !defined(__alpha_bwx__)
96 typedef u32 __bitwise blk_status_t;
97 typedef u32 blk_short_t;
98 #else
99 typedef u8 __bitwise blk_status_t;
100 typedef u16 blk_short_t;
101 #endif
102 #define BLK_STS_OK 0
103 #define BLK_STS_NOTSUPP ((__force blk_status_t)1)
104 #define BLK_STS_TIMEOUT ((__force blk_status_t)2)
105 #define BLK_STS_NOSPC ((__force blk_status_t)3)
106 #define BLK_STS_TRANSPORT ((__force blk_status_t)4)
107 #define BLK_STS_TARGET ((__force blk_status_t)5)
108 #define BLK_STS_RESV_CONFLICT ((__force blk_status_t)6)
109 #define BLK_STS_MEDIUM ((__force blk_status_t)7)
110 #define BLK_STS_PROTECTION ((__force blk_status_t)8)
111 #define BLK_STS_RESOURCE ((__force blk_status_t)9)
112 #define BLK_STS_IOERR ((__force blk_status_t)10)
113
114 /* hack for device mapper, don't use elsewhere: */
115 #define BLK_STS_DM_REQUEUE ((__force blk_status_t)11)
116
117 /*
118 * BLK_STS_AGAIN should only be returned if RQF_NOWAIT is set
119 * and the bio would block (cf bio_wouldblock_error())
120 */
121 #define BLK_STS_AGAIN ((__force blk_status_t)12)
122
123 /*
124 * BLK_STS_DEV_RESOURCE is returned from the driver to the block layer if
125 * device related resources are unavailable, but the driver can guarantee
126 * that the queue will be rerun in the future once resources become
127 * available again. This is typically the case for device specific
128 * resources that are consumed for IO. If the driver fails allocating these
129 * resources, we know that inflight (or pending) IO will free these
130 * resource upon completion.
131 *
132 * This is different from BLK_STS_RESOURCE in that it explicitly references
133 * a device specific resource. For resources of wider scope, allocation
134 * failure can happen without having pending IO. This means that we can't
135 * rely on request completions freeing these resources, as IO may not be in
136 * flight. Examples of that are kernel memory allocations, DMA mappings, or
137 * any other system wide resources.
138 */
139 #define BLK_STS_DEV_RESOURCE ((__force blk_status_t)13)
140
141 /*
142 * BLK_STS_ZONE_RESOURCE is returned from the driver to the block layer if zone
143 * related resources are unavailable, but the driver can guarantee the queue
144 * will be rerun in the future once the resources become available again.
145 *
146 * This is different from BLK_STS_DEV_RESOURCE in that it explicitly references
147 * a zone specific resource and IO to a different zone on the same device could
148 * still be served. Examples of that are zones that are write-locked, but a read
149 * to the same zone could be served.
150 */
151 #define BLK_STS_ZONE_RESOURCE ((__force blk_status_t)14)
152
153 /*
154 * BLK_STS_ZONE_OPEN_RESOURCE is returned from the driver in the completion
155 * path if the device returns a status indicating that too many zone resources
156 * are currently open. The same command should be successful if resubmitted
157 * after the number of open zones decreases below the device's limits, which is
158 * reported in the request_queue's max_open_zones.
159 */
160 #define BLK_STS_ZONE_OPEN_RESOURCE ((__force blk_status_t)15)
161
162 /*
163 * BLK_STS_ZONE_ACTIVE_RESOURCE is returned from the driver in the completion
164 * path if the device returns a status indicating that too many zone resources
165 * are currently active. The same command should be successful if resubmitted
166 * after the number of active zones decreases below the device's limits, which
167 * is reported in the request_queue's max_active_zones.
168 */
169 #define BLK_STS_ZONE_ACTIVE_RESOURCE ((__force blk_status_t)16)
170
171 /*
172 * BLK_STS_OFFLINE is returned from the driver when the target device is offline
173 * or is being taken offline. This could help differentiate the case where a
174 * device is intentionally being shut down from a real I/O error.
175 */
176 #define BLK_STS_OFFLINE ((__force blk_status_t)17)
177
178 /*
179 * BLK_STS_DURATION_LIMIT is returned from the driver when the target device
180 * aborted the command because it exceeded one of its Command Duration Limits.
181 */
182 #define BLK_STS_DURATION_LIMIT ((__force blk_status_t)18)
183
184 /**
185 * blk_path_error - returns true if error may be path related
186 * @error: status the request was completed with
187 *
188 * Description:
189 * This classifies block error status into non-retryable errors and ones
190 * that may be successful if retried on a failover path.
191 *
192 * Return:
193 * %false - retrying failover path will not help
194 * %true - may succeed if retried
195 */
blk_path_error(blk_status_t error)196 static inline bool blk_path_error(blk_status_t error)
197 {
198 switch (error) {
199 case BLK_STS_NOTSUPP:
200 case BLK_STS_NOSPC:
201 case BLK_STS_TARGET:
202 case BLK_STS_RESV_CONFLICT:
203 case BLK_STS_MEDIUM:
204 case BLK_STS_PROTECTION:
205 return false;
206 }
207
208 /* Anything else could be a path failure, so should be retried */
209 return true;
210 }
211
212 /*
213 * From most significant bit:
214 * 1 bit: reserved for other usage, see below
215 * 12 bits: original size of bio
216 * 51 bits: issue time of bio
217 */
218 #define BIO_ISSUE_RES_BITS 1
219 #define BIO_ISSUE_SIZE_BITS 12
220 #define BIO_ISSUE_RES_SHIFT (64 - BIO_ISSUE_RES_BITS)
221 #define BIO_ISSUE_SIZE_SHIFT (BIO_ISSUE_RES_SHIFT - BIO_ISSUE_SIZE_BITS)
222 #define BIO_ISSUE_TIME_MASK ((1ULL << BIO_ISSUE_SIZE_SHIFT) - 1)
223 #define BIO_ISSUE_SIZE_MASK \
224 (((1ULL << BIO_ISSUE_SIZE_BITS) - 1) << BIO_ISSUE_SIZE_SHIFT)
225 #define BIO_ISSUE_RES_MASK (~((1ULL << BIO_ISSUE_RES_SHIFT) - 1))
226
227 /* Reserved bit for blk-throtl */
228 #define BIO_ISSUE_THROTL_SKIP_LATENCY (1ULL << 63)
229
230 struct bio_issue {
231 u64 value;
232 };
233
__bio_issue_time(u64 time)234 static inline u64 __bio_issue_time(u64 time)
235 {
236 return time & BIO_ISSUE_TIME_MASK;
237 }
238
bio_issue_time(struct bio_issue * issue)239 static inline u64 bio_issue_time(struct bio_issue *issue)
240 {
241 return __bio_issue_time(issue->value);
242 }
243
bio_issue_size(struct bio_issue * issue)244 static inline sector_t bio_issue_size(struct bio_issue *issue)
245 {
246 return ((issue->value & BIO_ISSUE_SIZE_MASK) >> BIO_ISSUE_SIZE_SHIFT);
247 }
248
bio_issue_init(struct bio_issue * issue,sector_t size)249 static inline void bio_issue_init(struct bio_issue *issue,
250 sector_t size)
251 {
252 size &= (1ULL << BIO_ISSUE_SIZE_BITS) - 1;
253 issue->value = ((issue->value & BIO_ISSUE_RES_MASK) |
254 (ktime_get_ns() & BIO_ISSUE_TIME_MASK) |
255 ((u64)size << BIO_ISSUE_SIZE_SHIFT));
256 }
257
258 typedef __u32 __bitwise blk_opf_t;
259
260 typedef unsigned int blk_qc_t;
261 #define BLK_QC_T_NONE -1U
262
263 /*
264 * main unit of I/O for the block layer and lower layers (ie drivers and
265 * stacking drivers)
266 */
267 struct bio {
268 struct bio *bi_next; /* request queue link */
269 struct block_device *bi_bdev;
270 blk_opf_t bi_opf; /* bottom bits REQ_OP, top bits
271 * req_flags.
272 */
273 unsigned short bi_flags; /* BIO_* below */
274 unsigned short bi_ioprio;
275 enum rw_hint bi_write_hint;
276 blk_status_t bi_status;
277 atomic_t __bi_remaining;
278
279 struct bvec_iter bi_iter;
280
281 blk_qc_t bi_cookie;
282 bio_end_io_t *bi_end_io;
283 void *bi_private;
284 #ifdef CONFIG_BLK_CGROUP
285 /*
286 * Represents the association of the css and request_queue for the bio.
287 * If a bio goes direct to device, it will not have a blkg as it will
288 * not have a request_queue associated with it. The reference is put
289 * on release of the bio.
290 */
291 struct blkcg_gq *bi_blkg;
292 struct bio_issue bi_issue;
293 #ifdef CONFIG_BLK_CGROUP_IOCOST
294 u64 bi_iocost_cost;
295 #endif
296 #endif
297
298 #ifdef CONFIG_BLK_INLINE_ENCRYPTION
299 struct bio_crypt_ctx *bi_crypt_context;
300 #if IS_ENABLED(CONFIG_DM_DEFAULT_KEY)
301 bool bi_skip_dm_default_key;
302 #endif
303 #endif
304
305 union {
306 #if defined(CONFIG_BLK_DEV_INTEGRITY)
307 struct bio_integrity_payload *bi_integrity; /* data integrity */
308 #endif
309 };
310
311 unsigned short bi_vcnt; /* how many bio_vec's */
312
313 /*
314 * Everything starting with bi_max_vecs will be preserved by bio_reset()
315 */
316
317 unsigned short bi_max_vecs; /* max bvl_vecs we can hold */
318
319 atomic_t __bi_cnt; /* pin count */
320
321 struct bio_vec *bi_io_vec; /* the actual vec list */
322
323 struct bio_set *bi_pool;
324
325 ANDROID_OEM_DATA(1);
326 ANDROID_KABI_RESERVE(1);
327 ANDROID_KABI_RESERVE(2);
328
329 /*
330 * We can inline a number of vecs at the end of the bio, to avoid
331 * double allocations for a small number of bio_vecs. This member
332 * MUST obviously be kept at the very end of the bio.
333 */
334 struct bio_vec bi_inline_vecs[];
335 };
336
337 #define BIO_RESET_BYTES offsetof(struct bio, bi_max_vecs)
338 #define BIO_MAX_SECTORS (UINT_MAX >> SECTOR_SHIFT)
339
340 /*
341 * bio flags
342 */
343 enum {
344 BIO_PAGE_PINNED, /* Unpin pages in bio_release_pages() */
345 BIO_CLONED, /* doesn't own data */
346 BIO_BOUNCED, /* bio is a bounce bio */
347 BIO_QUIET, /* Make BIO Quiet */
348 BIO_CHAIN, /* chained bio, ->bi_remaining in effect */
349 BIO_REFFED, /* bio has elevated ->bi_cnt */
350 BIO_BPS_THROTTLED, /* This bio has already been subjected to
351 * throttling rules. Don't do it again. */
352 BIO_TRACE_COMPLETION, /* bio_endio() should trace the final completion
353 * of this bio. */
354 BIO_CGROUP_ACCT, /* has been accounted to a cgroup */
355 BIO_QOS_THROTTLED, /* bio went through rq_qos throttle path */
356 BIO_QOS_MERGED, /* but went through rq_qos merge path */
357 BIO_REMAPPED,
358 BIO_ZONE_WRITE_LOCKED, /* Owns a zoned device zone write lock */
359 BIO_FLAG_LAST
360 };
361
362 typedef __u32 __bitwise blk_mq_req_flags_t;
363
364 #define REQ_OP_BITS 8
365 #define REQ_OP_MASK (__force blk_opf_t)((1 << REQ_OP_BITS) - 1)
366 #define REQ_FLAG_BITS 24
367
368 /**
369 * enum req_op - Operations common to the bio and request structures.
370 * We use 8 bits for encoding the operation, and the remaining 24 for flags.
371 *
372 * The least significant bit of the operation number indicates the data
373 * transfer direction:
374 *
375 * - if the least significant bit is set transfers are TO the device
376 * - if the least significant bit is not set transfers are FROM the device
377 *
378 * If a operation does not transfer data the least significant bit has no
379 * meaning.
380 */
381 enum req_op {
382 /* read sectors from the device */
383 REQ_OP_READ = (__force blk_opf_t)0,
384 /* write sectors to the device */
385 REQ_OP_WRITE = (__force blk_opf_t)1,
386 /* flush the volatile write cache */
387 REQ_OP_FLUSH = (__force blk_opf_t)2,
388 /* discard sectors */
389 REQ_OP_DISCARD = (__force blk_opf_t)3,
390 /* securely erase sectors */
391 REQ_OP_SECURE_ERASE = (__force blk_opf_t)5,
392 /* write the zero filled sector many times */
393 REQ_OP_WRITE_ZEROES = (__force blk_opf_t)9,
394 /* Open a zone */
395 REQ_OP_ZONE_OPEN = (__force blk_opf_t)10,
396 /* Close a zone */
397 REQ_OP_ZONE_CLOSE = (__force blk_opf_t)11,
398 /* Transition a zone to full */
399 REQ_OP_ZONE_FINISH = (__force blk_opf_t)12,
400 /* write data at the current zone write pointer */
401 REQ_OP_ZONE_APPEND = (__force blk_opf_t)13,
402 /* reset a zone write pointer */
403 REQ_OP_ZONE_RESET = (__force blk_opf_t)15,
404 /* reset all the zone present on the device */
405 REQ_OP_ZONE_RESET_ALL = (__force blk_opf_t)17,
406
407 /* Driver private requests */
408 REQ_OP_DRV_IN = (__force blk_opf_t)34,
409 REQ_OP_DRV_OUT = (__force blk_opf_t)35,
410
411 REQ_OP_LAST = (__force blk_opf_t)36,
412 };
413
414 enum req_flag_bits {
415 __REQ_FAILFAST_DEV = /* no driver retries of device errors */
416 REQ_OP_BITS,
417 __REQ_FAILFAST_TRANSPORT, /* no driver retries of transport errors */
418 __REQ_FAILFAST_DRIVER, /* no driver retries of driver errors */
419 __REQ_SYNC, /* request is sync (sync write or read) */
420 __REQ_META, /* metadata io request */
421 __REQ_PRIO, /* boost priority in cfq */
422 __REQ_NOMERGE, /* don't touch this for merging */
423 __REQ_IDLE, /* anticipate more IO after this one */
424 __REQ_INTEGRITY, /* I/O includes block integrity payload */
425 __REQ_FUA, /* forced unit access */
426 __REQ_PREFLUSH, /* request for cache flush */
427 __REQ_RAHEAD, /* read ahead, can fail anytime */
428 __REQ_BACKGROUND, /* background IO */
429 __REQ_NOWAIT, /* Don't wait if request will block */
430 __REQ_POLLED, /* caller polls for completion using bio_poll */
431 __REQ_ALLOC_CACHE, /* allocate IO from cache if available */
432 __REQ_SWAP, /* swap I/O */
433 __REQ_DRV, /* for driver use */
434 __REQ_FS_PRIVATE, /* for file system (submitter) use */
435
436 /*
437 * Command specific flags, keep last:
438 */
439 /* for REQ_OP_WRITE_ZEROES: */
440 __REQ_NOUNMAP, /* do not free blocks when zeroing */
441
442 __REQ_NR_BITS, /* stops here */
443 };
444
445 #define REQ_FAILFAST_DEV \
446 (__force blk_opf_t)(1ULL << __REQ_FAILFAST_DEV)
447 #define REQ_FAILFAST_TRANSPORT \
448 (__force blk_opf_t)(1ULL << __REQ_FAILFAST_TRANSPORT)
449 #define REQ_FAILFAST_DRIVER \
450 (__force blk_opf_t)(1ULL << __REQ_FAILFAST_DRIVER)
451 #define REQ_SYNC (__force blk_opf_t)(1ULL << __REQ_SYNC)
452 #define REQ_META (__force blk_opf_t)(1ULL << __REQ_META)
453 #define REQ_PRIO (__force blk_opf_t)(1ULL << __REQ_PRIO)
454 #define REQ_NOMERGE (__force blk_opf_t)(1ULL << __REQ_NOMERGE)
455 #define REQ_IDLE (__force blk_opf_t)(1ULL << __REQ_IDLE)
456 #define REQ_INTEGRITY (__force blk_opf_t)(1ULL << __REQ_INTEGRITY)
457 #define REQ_FUA (__force blk_opf_t)(1ULL << __REQ_FUA)
458 #define REQ_PREFLUSH (__force blk_opf_t)(1ULL << __REQ_PREFLUSH)
459 #define REQ_RAHEAD (__force blk_opf_t)(1ULL << __REQ_RAHEAD)
460 #define REQ_BACKGROUND (__force blk_opf_t)(1ULL << __REQ_BACKGROUND)
461 #define REQ_NOWAIT (__force blk_opf_t)(1ULL << __REQ_NOWAIT)
462 #define REQ_POLLED (__force blk_opf_t)(1ULL << __REQ_POLLED)
463 #define REQ_ALLOC_CACHE (__force blk_opf_t)(1ULL << __REQ_ALLOC_CACHE)
464 #define REQ_SWAP (__force blk_opf_t)(1ULL << __REQ_SWAP)
465 #define REQ_DRV (__force blk_opf_t)(1ULL << __REQ_DRV)
466 #define REQ_FS_PRIVATE (__force blk_opf_t)(1ULL << __REQ_FS_PRIVATE)
467
468 #define REQ_NOUNMAP (__force blk_opf_t)(1ULL << __REQ_NOUNMAP)
469
470 #define REQ_FAILFAST_MASK \
471 (REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT | REQ_FAILFAST_DRIVER)
472
473 #define REQ_NOMERGE_FLAGS \
474 (REQ_NOMERGE | REQ_PREFLUSH | REQ_FUA)
475
476 enum stat_group {
477 STAT_READ,
478 STAT_WRITE,
479 STAT_DISCARD,
480 STAT_FLUSH,
481
482 NR_STAT_GROUPS
483 };
484
bio_op(const struct bio * bio)485 static inline enum req_op bio_op(const struct bio *bio)
486 {
487 return bio->bi_opf & REQ_OP_MASK;
488 }
489
op_is_write(blk_opf_t op)490 static inline bool op_is_write(blk_opf_t op)
491 {
492 return !!(op & (__force blk_opf_t)1);
493 }
494
495 /*
496 * Check if the bio or request is one that needs special treatment in the
497 * flush state machine.
498 */
op_is_flush(blk_opf_t op)499 static inline bool op_is_flush(blk_opf_t op)
500 {
501 return op & (REQ_FUA | REQ_PREFLUSH);
502 }
503
504 /*
505 * Reads are always treated as synchronous, as are requests with the FUA or
506 * PREFLUSH flag. Other operations may be marked as synchronous using the
507 * REQ_SYNC flag.
508 */
op_is_sync(blk_opf_t op)509 static inline bool op_is_sync(blk_opf_t op)
510 {
511 return (op & REQ_OP_MASK) == REQ_OP_READ ||
512 (op & (REQ_SYNC | REQ_FUA | REQ_PREFLUSH));
513 }
514
op_is_discard(blk_opf_t op)515 static inline bool op_is_discard(blk_opf_t op)
516 {
517 return (op & REQ_OP_MASK) == REQ_OP_DISCARD;
518 }
519
520 /*
521 * Check if a bio or request operation is a zone management operation, with
522 * the exception of REQ_OP_ZONE_RESET_ALL which is treated as a special case
523 * due to its different handling in the block layer and device response in
524 * case of command failure.
525 */
op_is_zone_mgmt(enum req_op op)526 static inline bool op_is_zone_mgmt(enum req_op op)
527 {
528 switch (op & REQ_OP_MASK) {
529 case REQ_OP_ZONE_RESET:
530 case REQ_OP_ZONE_OPEN:
531 case REQ_OP_ZONE_CLOSE:
532 case REQ_OP_ZONE_FINISH:
533 return true;
534 default:
535 return false;
536 }
537 }
538
op_stat_group(enum req_op op)539 static inline int op_stat_group(enum req_op op)
540 {
541 if (op_is_discard(op))
542 return STAT_DISCARD;
543 return op_is_write(op);
544 }
545
546 struct blk_rq_stat {
547 u64 mean;
548 u64 min;
549 u64 max;
550 u32 nr_samples;
551 u64 batch;
552 };
553
554 #endif /* __LINUX_BLK_TYPES_H */
555