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>
14 struct bio_integrity_payload
;
18 struct cgroup_subsys_state
;
19 typedef void (bio_end_io_t
) (struct bio
*);
22 * Block error status values. See block/blk-core:blk_errors for the details.
24 typedef u8 __bitwise blk_status_t
;
26 #define BLK_STS_NOTSUPP ((__force blk_status_t)1)
27 #define BLK_STS_TIMEOUT ((__force blk_status_t)2)
28 #define BLK_STS_NOSPC ((__force blk_status_t)3)
29 #define BLK_STS_TRANSPORT ((__force blk_status_t)4)
30 #define BLK_STS_TARGET ((__force blk_status_t)5)
31 #define BLK_STS_NEXUS ((__force blk_status_t)6)
32 #define BLK_STS_MEDIUM ((__force blk_status_t)7)
33 #define BLK_STS_PROTECTION ((__force blk_status_t)8)
34 #define BLK_STS_RESOURCE ((__force blk_status_t)9)
35 #define BLK_STS_IOERR ((__force blk_status_t)10)
37 /* hack for device mapper, don't use elsewhere: */
38 #define BLK_STS_DM_REQUEUE ((__force blk_status_t)11)
40 #define BLK_STS_AGAIN ((__force blk_status_t)12)
42 struct blk_issue_stat
{
47 * main unit of I/O for the block layer and lower layers (ie drivers and
51 struct bio
*bi_next
; /* request queue link */
52 struct gendisk
*bi_disk
;
54 blk_status_t bi_status
;
55 unsigned int bi_opf
; /* bottom bits req flags,
56 * top bits REQ_OP. Use
59 unsigned short bi_flags
; /* status, etc and bvec pool number */
60 unsigned short bi_ioprio
;
61 unsigned short bi_write_hint
;
63 struct bvec_iter bi_iter
;
65 /* Number of segments in this BIO after
66 * physical address coalescing is performed.
68 unsigned int bi_phys_segments
;
71 * To keep track of the max segment size, we account for the
72 * sizes of the first and last mergeable segments in this bio.
74 unsigned int bi_seg_front_size
;
75 unsigned int bi_seg_back_size
;
77 atomic_t __bi_remaining
;
79 bio_end_io_t
*bi_end_io
;
82 #ifdef CONFIG_BLK_CGROUP
84 * Optional ioc and css associated with this bio. Put on bio
85 * release. Read comment on top of bio_associate_current().
87 struct io_context
*bi_ioc
;
88 struct cgroup_subsys_state
*bi_css
;
89 #ifdef CONFIG_BLK_DEV_THROTTLING_LOW
91 struct blk_issue_stat bi_issue_stat
;
95 #if defined(CONFIG_BLK_DEV_INTEGRITY)
96 struct bio_integrity_payload
*bi_integrity
; /* data integrity */
100 unsigned short bi_vcnt
; /* how many bio_vec's */
103 * Everything starting with bi_max_vecs will be preserved by bio_reset()
106 unsigned short bi_max_vecs
; /* max bvl_vecs we can hold */
108 atomic_t __bi_cnt
; /* pin count */
110 struct bio_vec
*bi_io_vec
; /* the actual vec list */
112 struct bio_set
*bi_pool
;
115 * We can inline a number of vecs at the end of the bio, to avoid
116 * double allocations for a small number of bio_vecs. This member
117 * MUST obviously be kept at the very end of the bio.
119 struct bio_vec bi_inline_vecs
[0];
122 #define BIO_RESET_BYTES offsetof(struct bio, bi_max_vecs)
127 #define BIO_SEG_VALID 1 /* bi_phys_segments valid */
128 #define BIO_CLONED 2 /* doesn't own data */
129 #define BIO_BOUNCED 3 /* bio is a bounce bio */
130 #define BIO_USER_MAPPED 4 /* contains user pages */
131 #define BIO_NULL_MAPPED 5 /* contains invalid user pages */
132 #define BIO_QUIET 6 /* Make BIO Quiet */
133 #define BIO_CHAIN 7 /* chained bio, ->bi_remaining in effect */
134 #define BIO_REFFED 8 /* bio has elevated ->bi_cnt */
135 #define BIO_THROTTLED 9 /* This bio has already been subjected to
136 * throttling rules. Don't do it again. */
137 #define BIO_TRACE_COMPLETION 10 /* bio_endio() should trace the final completion
139 /* See BVEC_POOL_OFFSET below before adding new flags */
142 * We support 6 different bvec pools, the last one is magic in that it
143 * is backed by a mempool.
145 #define BVEC_POOL_NR 6
146 #define BVEC_POOL_MAX (BVEC_POOL_NR - 1)
149 * Top 3 bits of bio flags indicate the pool the bvecs came from. We add
150 * 1 to the actual index so that 0 indicates that there are no bvecs to be
153 #define BVEC_POOL_BITS (3)
154 #define BVEC_POOL_OFFSET (16 - BVEC_POOL_BITS)
155 #define BVEC_POOL_IDX(bio) ((bio)->bi_flags >> BVEC_POOL_OFFSET)
156 #if (1<< BVEC_POOL_BITS) < (BVEC_POOL_NR+1)
157 # error "BVEC_POOL_BITS is too small"
161 * Flags starting here get preserved by bio_reset() - this includes
162 * only BVEC_POOL_IDX()
164 #define BIO_RESET_BITS BVEC_POOL_OFFSET
167 * Operations and flags common to the bio and request structures.
168 * We use 8 bits for encoding the operation, and the remaining 24 for flags.
170 * The least significant bit of the operation number indicates the data
171 * transfer direction:
173 * - if the least significant bit is set transfers are TO the device
174 * - if the least significant bit is not set transfers are FROM the device
176 * If a operation does not transfer data the least significant bit has no
179 #define REQ_OP_BITS 8
180 #define REQ_OP_MASK ((1 << REQ_OP_BITS) - 1)
181 #define REQ_FLAG_BITS 24
184 /* read sectors from the device */
186 /* write sectors to the device */
188 /* flush the volatile write cache */
190 /* discard sectors */
192 /* get zone information */
193 REQ_OP_ZONE_REPORT
= 4,
194 /* securely erase sectors */
195 REQ_OP_SECURE_ERASE
= 5,
196 /* seset a zone write pointer */
197 REQ_OP_ZONE_RESET
= 6,
198 /* write the same sector many times */
199 REQ_OP_WRITE_SAME
= 7,
200 /* write the zero filled sector many times */
201 REQ_OP_WRITE_ZEROES
= 9,
203 /* SCSI passthrough using struct scsi_request */
205 REQ_OP_SCSI_OUT
= 33,
206 /* Driver private requests */
214 __REQ_FAILFAST_DEV
= /* no driver retries of device errors */
216 __REQ_FAILFAST_TRANSPORT
, /* no driver retries of transport errors */
217 __REQ_FAILFAST_DRIVER
, /* no driver retries of driver errors */
218 __REQ_SYNC
, /* request is sync (sync write or read) */
219 __REQ_META
, /* metadata io request */
220 __REQ_PRIO
, /* boost priority in cfq */
221 __REQ_NOMERGE
, /* don't touch this for merging */
222 __REQ_IDLE
, /* anticipate more IO after this one */
223 __REQ_INTEGRITY
, /* I/O includes block integrity payload */
224 __REQ_FUA
, /* forced unit access */
225 __REQ_PREFLUSH
, /* request for cache flush */
226 __REQ_RAHEAD
, /* read ahead, can fail anytime */
227 __REQ_BACKGROUND
, /* background IO */
229 /* command specific flags for REQ_OP_WRITE_ZEROES: */
230 __REQ_NOUNMAP
, /* do not free blocks when zeroing */
232 __REQ_NOWAIT
, /* Don't wait if request will block */
233 __REQ_NR_BITS
, /* stops here */
236 #define REQ_FAILFAST_DEV (1ULL << __REQ_FAILFAST_DEV)
237 #define REQ_FAILFAST_TRANSPORT (1ULL << __REQ_FAILFAST_TRANSPORT)
238 #define REQ_FAILFAST_DRIVER (1ULL << __REQ_FAILFAST_DRIVER)
239 #define REQ_SYNC (1ULL << __REQ_SYNC)
240 #define REQ_META (1ULL << __REQ_META)
241 #define REQ_PRIO (1ULL << __REQ_PRIO)
242 #define REQ_NOMERGE (1ULL << __REQ_NOMERGE)
243 #define REQ_IDLE (1ULL << __REQ_IDLE)
244 #define REQ_INTEGRITY (1ULL << __REQ_INTEGRITY)
245 #define REQ_FUA (1ULL << __REQ_FUA)
246 #define REQ_PREFLUSH (1ULL << __REQ_PREFLUSH)
247 #define REQ_RAHEAD (1ULL << __REQ_RAHEAD)
248 #define REQ_BACKGROUND (1ULL << __REQ_BACKGROUND)
250 #define REQ_NOUNMAP (1ULL << __REQ_NOUNMAP)
251 #define REQ_NOWAIT (1ULL << __REQ_NOWAIT)
253 #define REQ_FAILFAST_MASK \
254 (REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT | REQ_FAILFAST_DRIVER)
256 #define REQ_NOMERGE_FLAGS \
257 (REQ_NOMERGE | REQ_PREFLUSH | REQ_FUA)
259 #define bio_op(bio) \
260 ((bio)->bi_opf & REQ_OP_MASK)
261 #define req_op(req) \
262 ((req)->cmd_flags & REQ_OP_MASK)
264 /* obsolete, don't use in new code */
265 static inline void bio_set_op_attrs(struct bio
*bio
, unsigned op
,
268 bio
->bi_opf
= op
| op_flags
;
271 static inline bool op_is_write(unsigned int op
)
277 * Check if the bio or request is one that needs special treatment in the
278 * flush state machine.
280 static inline bool op_is_flush(unsigned int op
)
282 return op
& (REQ_FUA
| REQ_PREFLUSH
);
286 * Reads are always treated as synchronous, as are requests with the FUA or
287 * PREFLUSH flag. Other operations may be marked as synchronous using the
290 static inline bool op_is_sync(unsigned int op
)
292 return (op
& REQ_OP_MASK
) == REQ_OP_READ
||
293 (op
& (REQ_SYNC
| REQ_FUA
| REQ_PREFLUSH
));
296 typedef unsigned int blk_qc_t
;
297 #define BLK_QC_T_NONE -1U
298 #define BLK_QC_T_SHIFT 16
299 #define BLK_QC_T_INTERNAL (1U << 31)
301 static inline bool blk_qc_t_valid(blk_qc_t cookie
)
303 return cookie
!= BLK_QC_T_NONE
;
306 static inline blk_qc_t
blk_tag_to_qc_t(unsigned int tag
, unsigned int queue_num
,
309 blk_qc_t ret
= tag
| (queue_num
<< BLK_QC_T_SHIFT
);
312 ret
|= BLK_QC_T_INTERNAL
;
317 static inline unsigned int blk_qc_t_to_queue_num(blk_qc_t cookie
)
319 return (cookie
& ~BLK_QC_T_INTERNAL
) >> BLK_QC_T_SHIFT
;
322 static inline unsigned int blk_qc_t_to_tag(blk_qc_t cookie
)
324 return cookie
& ((1u << BLK_QC_T_SHIFT
) - 1);
327 static inline bool blk_qc_t_is_internal(blk_qc_t cookie
)
329 return (cookie
& BLK_QC_T_INTERNAL
) != 0;
341 #endif /* __LINUX_BLK_TYPES_H */