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