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;
53 unsigned int bi_opf; /* bottom bits req flags,
54 * top bits REQ_OP. Use
57 unsigned short bi_flags; /* status, etc and bvec pool number */
58 unsigned short bi_ioprio;
59 unsigned short bi_write_hint;
60 blk_status_t bi_status;
63 /* Number of segments in this BIO after
64 * physical address coalescing is performed.
66 unsigned int bi_phys_segments;
69 * To keep track of the max segment size, we account for the
70 * sizes of the first and last mergeable segments in this bio.
72 unsigned int bi_seg_front_size;
73 unsigned int bi_seg_back_size;
75 struct bvec_iter bi_iter;
77 atomic_t __bi_remaining;
78 bio_end_io_t *bi_end_io;
81 #ifdef CONFIG_BLK_CGROUP
83 * Optional ioc and css associated with this bio. Put on bio
84 * release. Read comment on top of bio_associate_current().
86 struct io_context *bi_ioc;
87 struct cgroup_subsys_state *bi_css;
88 #ifdef CONFIG_BLK_DEV_THROTTLING_LOW
90 struct blk_issue_stat bi_issue_stat;
94 #if defined(CONFIG_BLK_DEV_INTEGRITY)
95 struct bio_integrity_payload *bi_integrity; /* data integrity */
99 unsigned short bi_vcnt; /* how many bio_vec's */
102 * Everything starting with bi_max_vecs will be preserved by bio_reset()
105 unsigned short bi_max_vecs; /* max bvl_vecs we can hold */
107 atomic_t __bi_cnt; /* pin count */
109 struct bio_vec *bi_io_vec; /* the actual vec list */
111 struct bio_set *bi_pool;
114 * We can inline a number of vecs at the end of the bio, to avoid
115 * double allocations for a small number of bio_vecs. This member
116 * MUST obviously be kept at the very end of the bio.
118 struct bio_vec bi_inline_vecs[0];
121 #define BIO_RESET_BYTES offsetof(struct bio, bi_max_vecs)
126 #define BIO_SEG_VALID 1 /* bi_phys_segments valid */
127 #define BIO_CLONED 2 /* doesn't own data */
128 #define BIO_BOUNCED 3 /* bio is a bounce bio */
129 #define BIO_USER_MAPPED 4 /* contains user pages */
130 #define BIO_NULL_MAPPED 5 /* contains invalid user pages */
131 #define BIO_QUIET 6 /* Make BIO Quiet */
132 #define BIO_CHAIN 7 /* chained bio, ->bi_remaining in effect */
133 #define BIO_REFFED 8 /* bio has elevated ->bi_cnt */
134 #define BIO_THROTTLED 9 /* This bio has already been subjected to
135 * throttling rules. Don't do it again. */
136 #define BIO_TRACE_COMPLETION 10 /* bio_endio() should trace the final completion
138 /* See BVEC_POOL_OFFSET below before adding new flags */
141 * We support 6 different bvec pools, the last one is magic in that it
142 * is backed by a mempool.
144 #define BVEC_POOL_NR 6
145 #define BVEC_POOL_MAX (BVEC_POOL_NR - 1)
148 * Top 3 bits of bio flags indicate the pool the bvecs came from. We add
149 * 1 to the actual index so that 0 indicates that there are no bvecs to be
152 #define BVEC_POOL_BITS (3)
153 #define BVEC_POOL_OFFSET (16 - BVEC_POOL_BITS)
154 #define BVEC_POOL_IDX(bio) ((bio)->bi_flags >> BVEC_POOL_OFFSET)
155 #if (1<< BVEC_POOL_BITS) < (BVEC_POOL_NR+1)
156 # error "BVEC_POOL_BITS is too small"
160 * Flags starting here get preserved by bio_reset() - this includes
161 * only BVEC_POOL_IDX()
163 #define BIO_RESET_BITS BVEC_POOL_OFFSET
165 typedef __u32 __bitwise blk_mq_req_flags_t;
168 * Operations and flags common to the bio and request structures.
169 * We use 8 bits for encoding the operation, and the remaining 24 for flags.
171 * The least significant bit of the operation number indicates the data
172 * transfer direction:
174 * - if the least significant bit is set transfers are TO the device
175 * - if the least significant bit is not set transfers are FROM the device
177 * If a operation does not transfer data the least significant bit has no
180 #define REQ_OP_BITS 8
181 #define REQ_OP_MASK ((1 << REQ_OP_BITS) - 1)
182 #define REQ_FLAG_BITS 24
185 /* read sectors from the device */
187 /* write sectors to the device */
189 /* flush the volatile write cache */
191 /* discard sectors */
193 /* get zone information */
194 REQ_OP_ZONE_REPORT = 4,
195 /* securely erase sectors */
196 REQ_OP_SECURE_ERASE = 5,
197 /* seset a zone write pointer */
198 REQ_OP_ZONE_RESET = 6,
199 /* write the same sector many times */
200 REQ_OP_WRITE_SAME = 7,
201 /* write the zero filled sector many times */
202 REQ_OP_WRITE_ZEROES = 9,
204 /* SCSI passthrough using struct scsi_request */
206 REQ_OP_SCSI_OUT = 33,
207 /* Driver private requests */
215 __REQ_FAILFAST_DEV = /* no driver retries of device errors */
217 __REQ_FAILFAST_TRANSPORT, /* no driver retries of transport errors */
218 __REQ_FAILFAST_DRIVER, /* no driver retries of driver errors */
219 __REQ_SYNC, /* request is sync (sync write or read) */
220 __REQ_META, /* metadata io request */
221 __REQ_PRIO, /* boost priority in cfq */
222 __REQ_NOMERGE, /* don't touch this for merging */
223 __REQ_IDLE, /* anticipate more IO after this one */
224 __REQ_INTEGRITY, /* I/O includes block integrity payload */
225 __REQ_FUA, /* forced unit access */
226 __REQ_PREFLUSH, /* request for cache flush */
227 __REQ_RAHEAD, /* read ahead, can fail anytime */
228 __REQ_BACKGROUND, /* background IO */
229 __REQ_NOWAIT, /* Don't wait if request will block */
231 /* command specific flags for REQ_OP_WRITE_ZEROES: */
232 __REQ_NOUNMAP, /* do not free blocks when zeroing */
237 __REQ_NR_BITS, /* stops here */
240 #define REQ_FAILFAST_DEV (1ULL << __REQ_FAILFAST_DEV)
241 #define REQ_FAILFAST_TRANSPORT (1ULL << __REQ_FAILFAST_TRANSPORT)
242 #define REQ_FAILFAST_DRIVER (1ULL << __REQ_FAILFAST_DRIVER)
243 #define REQ_SYNC (1ULL << __REQ_SYNC)
244 #define REQ_META (1ULL << __REQ_META)
245 #define REQ_PRIO (1ULL << __REQ_PRIO)
246 #define REQ_NOMERGE (1ULL << __REQ_NOMERGE)
247 #define REQ_IDLE (1ULL << __REQ_IDLE)
248 #define REQ_INTEGRITY (1ULL << __REQ_INTEGRITY)
249 #define REQ_FUA (1ULL << __REQ_FUA)
250 #define REQ_PREFLUSH (1ULL << __REQ_PREFLUSH)
251 #define REQ_RAHEAD (1ULL << __REQ_RAHEAD)
252 #define REQ_BACKGROUND (1ULL << __REQ_BACKGROUND)
253 #define REQ_NOWAIT (1ULL << __REQ_NOWAIT)
255 #define REQ_NOUNMAP (1ULL << __REQ_NOUNMAP)
257 #define REQ_DRV (1ULL << __REQ_DRV)
259 #define REQ_FAILFAST_MASK \
260 (REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT | REQ_FAILFAST_DRIVER)
262 #define REQ_NOMERGE_FLAGS \
263 (REQ_NOMERGE | REQ_PREFLUSH | REQ_FUA)
265 #define bio_op(bio) \
266 ((bio)->bi_opf & REQ_OP_MASK)
267 #define req_op(req) \
268 ((req)->cmd_flags & REQ_OP_MASK)
270 /* obsolete, don't use in new code */
271 static inline void bio_set_op_attrs(struct bio *bio, unsigned op,
274 bio->bi_opf = op | op_flags;
277 static inline bool op_is_write(unsigned int op)
283 * Check if the bio or request is one that needs special treatment in the
284 * flush state machine.
286 static inline bool op_is_flush(unsigned int op)
288 return op & (REQ_FUA | REQ_PREFLUSH);
292 * Reads are always treated as synchronous, as are requests with the FUA or
293 * PREFLUSH flag. Other operations may be marked as synchronous using the
296 static inline bool op_is_sync(unsigned int op)
298 return (op & REQ_OP_MASK) == REQ_OP_READ ||
299 (op & (REQ_SYNC | REQ_FUA | REQ_PREFLUSH));
302 typedef unsigned int blk_qc_t;
303 #define BLK_QC_T_NONE -1U
304 #define BLK_QC_T_SHIFT 16
305 #define BLK_QC_T_INTERNAL (1U << 31)
307 static inline bool blk_qc_t_valid(blk_qc_t cookie)
309 return cookie != BLK_QC_T_NONE;
312 static inline blk_qc_t blk_tag_to_qc_t(unsigned int tag, unsigned int queue_num,
315 blk_qc_t ret = tag | (queue_num << BLK_QC_T_SHIFT);
318 ret |= BLK_QC_T_INTERNAL;
323 static inline unsigned int blk_qc_t_to_queue_num(blk_qc_t cookie)
325 return (cookie & ~BLK_QC_T_INTERNAL) >> BLK_QC_T_SHIFT;
328 static inline unsigned int blk_qc_t_to_tag(blk_qc_t cookie)
330 return cookie & ((1u << BLK_QC_T_SHIFT) - 1);
333 static inline bool blk_qc_t_is_internal(blk_qc_t cookie)
335 return (cookie & BLK_QC_T_INTERNAL) != 0;
346 #endif /* __LINUX_BLK_TYPES_H */