1 /* SPDX-License-Identifier: GPL-2.0 */
3 * Block data types and constants. Directly include this file only to
4 * break include dependency loop.
6 #ifndef __LINUX_BLK_TYPES_H
7 #define __LINUX_BLK_TYPES_H
9 #include <linux/types.h>
10 #include <linux/bvec.h>
11 #include <linux/ktime.h>
15 struct bio_integrity_payload
;
19 struct cgroup_subsys_state
;
20 typedef void (bio_end_io_t
) (struct bio
*);
23 * Block error status values. See block/blk-core:blk_errors for the details.
24 * Alpha cannot write a byte atomically, so we need to use 32-bit value.
26 #if defined(CONFIG_ALPHA) && !defined(__alpha_bwx__)
27 typedef u32 __bitwise blk_status_t
;
29 typedef u8 __bitwise blk_status_t
;
32 #define BLK_STS_NOTSUPP ((__force blk_status_t)1)
33 #define BLK_STS_TIMEOUT ((__force blk_status_t)2)
34 #define BLK_STS_NOSPC ((__force blk_status_t)3)
35 #define BLK_STS_TRANSPORT ((__force blk_status_t)4)
36 #define BLK_STS_TARGET ((__force blk_status_t)5)
37 #define BLK_STS_NEXUS ((__force blk_status_t)6)
38 #define BLK_STS_MEDIUM ((__force blk_status_t)7)
39 #define BLK_STS_PROTECTION ((__force blk_status_t)8)
40 #define BLK_STS_RESOURCE ((__force blk_status_t)9)
41 #define BLK_STS_IOERR ((__force blk_status_t)10)
43 /* hack for device mapper, don't use elsewhere: */
44 #define BLK_STS_DM_REQUEUE ((__force blk_status_t)11)
46 #define BLK_STS_AGAIN ((__force blk_status_t)12)
49 * BLK_STS_DEV_RESOURCE is returned from the driver to the block layer if
50 * device related resources are unavailable, but the driver can guarantee
51 * that the queue will be rerun in the future once resources become
52 * available again. This is typically the case for device specific
53 * resources that are consumed for IO. If the driver fails allocating these
54 * resources, we know that inflight (or pending) IO will free these
55 * resource upon completion.
57 * This is different from BLK_STS_RESOURCE in that it explicitly references
58 * a device specific resource. For resources of wider scope, allocation
59 * failure can happen without having pending IO. This means that we can't
60 * rely on request completions freeing these resources, as IO may not be in
61 * flight. Examples of that are kernel memory allocations, DMA mappings, or
62 * any other system wide resources.
64 #define BLK_STS_DEV_RESOURCE ((__force blk_status_t)13)
67 * blk_path_error - returns true if error may be path related
68 * @error: status the request was completed with
71 * This classifies block error status into non-retryable errors and ones
72 * that may be successful if retried on a failover path.
75 * %false - retrying failover path will not help
76 * %true - may succeed if retried
78 static inline bool blk_path_error(blk_status_t error
)
86 case BLK_STS_PROTECTION
:
90 /* Anything else could be a path failure, so should be retried */
95 * From most significant bit:
96 * 1 bit: reserved for other usage, see below
97 * 12 bits: original size of bio
98 * 51 bits: issue time of bio
100 #define BIO_ISSUE_RES_BITS 1
101 #define BIO_ISSUE_SIZE_BITS 12
102 #define BIO_ISSUE_RES_SHIFT (64 - BIO_ISSUE_RES_BITS)
103 #define BIO_ISSUE_SIZE_SHIFT (BIO_ISSUE_RES_SHIFT - BIO_ISSUE_SIZE_BITS)
104 #define BIO_ISSUE_TIME_MASK ((1ULL << BIO_ISSUE_SIZE_SHIFT) - 1)
105 #define BIO_ISSUE_SIZE_MASK \
106 (((1ULL << BIO_ISSUE_SIZE_BITS) - 1) << BIO_ISSUE_SIZE_SHIFT)
107 #define BIO_ISSUE_RES_MASK (~((1ULL << BIO_ISSUE_RES_SHIFT) - 1))
109 /* Reserved bit for blk-throtl */
110 #define BIO_ISSUE_THROTL_SKIP_LATENCY (1ULL << 63)
116 static inline u64
__bio_issue_time(u64 time
)
118 return time
& BIO_ISSUE_TIME_MASK
;
121 static inline u64
bio_issue_time(struct bio_issue
*issue
)
123 return __bio_issue_time(issue
->value
);
126 static inline sector_t
bio_issue_size(struct bio_issue
*issue
)
128 return ((issue
->value
& BIO_ISSUE_SIZE_MASK
) >> BIO_ISSUE_SIZE_SHIFT
);
131 static inline void bio_issue_init(struct bio_issue
*issue
,
134 size
&= (1ULL << BIO_ISSUE_SIZE_BITS
) - 1;
135 issue
->value
= ((issue
->value
& BIO_ISSUE_RES_MASK
) |
136 (ktime_get_ns() & BIO_ISSUE_TIME_MASK
) |
137 ((u64
)size
<< BIO_ISSUE_SIZE_SHIFT
));
141 * main unit of I/O for the block layer and lower layers (ie drivers and
145 struct bio
*bi_next
; /* request queue link */
146 struct gendisk
*bi_disk
;
147 unsigned int bi_opf
; /* bottom bits req flags,
148 * top bits REQ_OP. Use
151 unsigned short bi_flags
; /* status, etc and bvec pool number */
152 unsigned short bi_ioprio
;
153 unsigned short bi_write_hint
;
154 blk_status_t bi_status
;
157 /* Number of segments in this BIO after
158 * physical address coalescing is performed.
160 unsigned int bi_phys_segments
;
163 * To keep track of the max segment size, we account for the
164 * sizes of the first and last mergeable segments in this bio.
166 unsigned int bi_seg_front_size
;
167 unsigned int bi_seg_back_size
;
169 struct bvec_iter bi_iter
;
171 atomic_t __bi_remaining
;
172 bio_end_io_t
*bi_end_io
;
175 #ifdef CONFIG_BLK_CGROUP
177 * Optional ioc and css associated with this bio. Put on bio
178 * release. Read comment on top of bio_associate_current().
180 struct io_context
*bi_ioc
;
181 struct cgroup_subsys_state
*bi_css
;
182 struct blkcg_gq
*bi_blkg
;
183 struct bio_issue bi_issue
;
186 #if defined(CONFIG_BLK_DEV_INTEGRITY)
187 struct bio_integrity_payload
*bi_integrity
; /* data integrity */
191 unsigned short bi_vcnt
; /* how many bio_vec's */
194 * Everything starting with bi_max_vecs will be preserved by bio_reset()
197 unsigned short bi_max_vecs
; /* max bvl_vecs we can hold */
199 atomic_t __bi_cnt
; /* pin count */
201 struct bio_vec
*bi_io_vec
; /* the actual vec list */
203 struct bio_set
*bi_pool
;
206 * We can inline a number of vecs at the end of the bio, to avoid
207 * double allocations for a small number of bio_vecs. This member
208 * MUST obviously be kept at the very end of the bio.
210 struct bio_vec bi_inline_vecs
[0];
213 #define BIO_RESET_BYTES offsetof(struct bio, bi_max_vecs)
218 #define BIO_SEG_VALID 1 /* bi_phys_segments valid */
219 #define BIO_CLONED 2 /* doesn't own data */
220 #define BIO_BOUNCED 3 /* bio is a bounce bio */
221 #define BIO_USER_MAPPED 4 /* contains user pages */
222 #define BIO_NULL_MAPPED 5 /* contains invalid user pages */
223 #define BIO_QUIET 6 /* Make BIO Quiet */
224 #define BIO_CHAIN 7 /* chained bio, ->bi_remaining in effect */
225 #define BIO_REFFED 8 /* bio has elevated ->bi_cnt */
226 #define BIO_THROTTLED 9 /* This bio has already been subjected to
227 * throttling rules. Don't do it again. */
228 #define BIO_TRACE_COMPLETION 10 /* bio_endio() should trace the final completion
230 #define BIO_QUEUE_ENTERED 11 /* can use blk_queue_enter_live() */
232 /* See BVEC_POOL_OFFSET below before adding new flags */
235 * We support 6 different bvec pools, the last one is magic in that it
236 * is backed by a mempool.
238 #define BVEC_POOL_NR 6
239 #define BVEC_POOL_MAX (BVEC_POOL_NR - 1)
242 * Top 3 bits of bio flags indicate the pool the bvecs came from. We add
243 * 1 to the actual index so that 0 indicates that there are no bvecs to be
246 #define BVEC_POOL_BITS (3)
247 #define BVEC_POOL_OFFSET (16 - BVEC_POOL_BITS)
248 #define BVEC_POOL_IDX(bio) ((bio)->bi_flags >> BVEC_POOL_OFFSET)
249 #if (1<< BVEC_POOL_BITS) < (BVEC_POOL_NR+1)
250 # error "BVEC_POOL_BITS is too small"
254 * Flags starting here get preserved by bio_reset() - this includes
255 * only BVEC_POOL_IDX()
257 #define BIO_RESET_BITS BVEC_POOL_OFFSET
259 typedef __u32 __bitwise blk_mq_req_flags_t
;
262 * Operations and flags common to the bio and request structures.
263 * We use 8 bits for encoding the operation, and the remaining 24 for flags.
265 * The least significant bit of the operation number indicates the data
266 * transfer direction:
268 * - if the least significant bit is set transfers are TO the device
269 * - if the least significant bit is not set transfers are FROM the device
271 * If a operation does not transfer data the least significant bit has no
274 #define REQ_OP_BITS 8
275 #define REQ_OP_MASK ((1 << REQ_OP_BITS) - 1)
276 #define REQ_FLAG_BITS 24
279 /* read sectors from the device */
281 /* write sectors to the device */
283 /* flush the volatile write cache */
285 /* discard sectors */
287 /* get zone information */
288 REQ_OP_ZONE_REPORT
= 4,
289 /* securely erase sectors */
290 REQ_OP_SECURE_ERASE
= 5,
291 /* seset a zone write pointer */
292 REQ_OP_ZONE_RESET
= 6,
293 /* write the same sector many times */
294 REQ_OP_WRITE_SAME
= 7,
295 /* write the zero filled sector many times */
296 REQ_OP_WRITE_ZEROES
= 9,
298 /* SCSI passthrough using struct scsi_request */
300 REQ_OP_SCSI_OUT
= 33,
301 /* Driver private requests */
309 __REQ_FAILFAST_DEV
= /* no driver retries of device errors */
311 __REQ_FAILFAST_TRANSPORT
, /* no driver retries of transport errors */
312 __REQ_FAILFAST_DRIVER
, /* no driver retries of driver errors */
313 __REQ_SYNC
, /* request is sync (sync write or read) */
314 __REQ_META
, /* metadata io request */
315 __REQ_PRIO
, /* boost priority in cfq */
316 __REQ_NOMERGE
, /* don't touch this for merging */
317 __REQ_IDLE
, /* anticipate more IO after this one */
318 __REQ_INTEGRITY
, /* I/O includes block integrity payload */
319 __REQ_FUA
, /* forced unit access */
320 __REQ_PREFLUSH
, /* request for cache flush */
321 __REQ_RAHEAD
, /* read ahead, can fail anytime */
322 __REQ_BACKGROUND
, /* background IO */
323 __REQ_NOWAIT
, /* Don't wait if request will block */
325 /* command specific flags for REQ_OP_WRITE_ZEROES: */
326 __REQ_NOUNMAP
, /* do not free blocks when zeroing */
330 __REQ_SWAP
, /* swapping request. */
331 __REQ_NR_BITS
, /* stops here */
334 #define REQ_FAILFAST_DEV (1ULL << __REQ_FAILFAST_DEV)
335 #define REQ_FAILFAST_TRANSPORT (1ULL << __REQ_FAILFAST_TRANSPORT)
336 #define REQ_FAILFAST_DRIVER (1ULL << __REQ_FAILFAST_DRIVER)
337 #define REQ_SYNC (1ULL << __REQ_SYNC)
338 #define REQ_META (1ULL << __REQ_META)
339 #define REQ_PRIO (1ULL << __REQ_PRIO)
340 #define REQ_NOMERGE (1ULL << __REQ_NOMERGE)
341 #define REQ_IDLE (1ULL << __REQ_IDLE)
342 #define REQ_INTEGRITY (1ULL << __REQ_INTEGRITY)
343 #define REQ_FUA (1ULL << __REQ_FUA)
344 #define REQ_PREFLUSH (1ULL << __REQ_PREFLUSH)
345 #define REQ_RAHEAD (1ULL << __REQ_RAHEAD)
346 #define REQ_BACKGROUND (1ULL << __REQ_BACKGROUND)
347 #define REQ_NOWAIT (1ULL << __REQ_NOWAIT)
349 #define REQ_NOUNMAP (1ULL << __REQ_NOUNMAP)
351 #define REQ_DRV (1ULL << __REQ_DRV)
352 #define REQ_SWAP (1ULL << __REQ_SWAP)
354 #define REQ_FAILFAST_MASK \
355 (REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT | REQ_FAILFAST_DRIVER)
357 #define REQ_NOMERGE_FLAGS \
358 (REQ_NOMERGE | REQ_PREFLUSH | REQ_FUA)
368 #define bio_op(bio) \
369 ((bio)->bi_opf & REQ_OP_MASK)
370 #define req_op(req) \
371 ((req)->cmd_flags & REQ_OP_MASK)
373 /* obsolete, don't use in new code */
374 static inline void bio_set_op_attrs(struct bio
*bio
, unsigned op
,
377 bio
->bi_opf
= op
| op_flags
;
380 static inline bool op_is_write(unsigned int op
)
386 * Check if the bio or request is one that needs special treatment in the
387 * flush state machine.
389 static inline bool op_is_flush(unsigned int op
)
391 return op
& (REQ_FUA
| REQ_PREFLUSH
);
395 * Reads are always treated as synchronous, as are requests with the FUA or
396 * PREFLUSH flag. Other operations may be marked as synchronous using the
399 static inline bool op_is_sync(unsigned int op
)
401 return (op
& REQ_OP_MASK
) == REQ_OP_READ
||
402 (op
& (REQ_SYNC
| REQ_FUA
| REQ_PREFLUSH
));
405 static inline bool op_is_discard(unsigned int op
)
407 return (op
& REQ_OP_MASK
) == REQ_OP_DISCARD
;
410 static inline int op_stat_group(unsigned int op
)
412 if (op_is_discard(op
))
414 return op_is_write(op
);
417 typedef unsigned int blk_qc_t
;
418 #define BLK_QC_T_NONE -1U
419 #define BLK_QC_T_SHIFT 16
420 #define BLK_QC_T_INTERNAL (1U << 31)
422 static inline bool blk_qc_t_valid(blk_qc_t cookie
)
424 return cookie
!= BLK_QC_T_NONE
;
427 static inline blk_qc_t
blk_tag_to_qc_t(unsigned int tag
, unsigned int queue_num
,
430 blk_qc_t ret
= tag
| (queue_num
<< BLK_QC_T_SHIFT
);
433 ret
|= BLK_QC_T_INTERNAL
;
438 static inline unsigned int blk_qc_t_to_queue_num(blk_qc_t cookie
)
440 return (cookie
& ~BLK_QC_T_INTERNAL
) >> BLK_QC_T_SHIFT
;
443 static inline unsigned int blk_qc_t_to_tag(blk_qc_t cookie
)
445 return cookie
& ((1u << BLK_QC_T_SHIFT
) - 1);
448 static inline bool blk_qc_t_is_internal(blk_qc_t cookie
)
450 return (cookie
& BLK_QC_T_INTERNAL
) != 0;
461 #endif /* __LINUX_BLK_TYPES_H */