Merge tag 'rpmsg-v4.16' of git://github.com/andersson/remoteproc
[linux-2.6-block.git] / include / linux / blk_types.h
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b2441318 1/* SPDX-License-Identifier: GPL-2.0 */
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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
7cc01581 9#include <linux/types.h>
0781e79e 10#include <linux/bvec.h>
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11
12struct bio_set;
13struct bio;
14struct bio_integrity_payload;
15struct page;
16struct block_device;
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17struct io_context;
18struct cgroup_subsys_state;
4246a0b6 19typedef void (bio_end_io_t) (struct bio *);
7cc01581 20
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21/*
22 * Block error status values. See block/blk-core:blk_errors for the details.
23 */
24typedef u8 __bitwise blk_status_t;
25#define BLK_STS_OK 0
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)
36
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37/* hack for device mapper, don't use elsewhere: */
38#define BLK_STS_DM_REQUEUE ((__force blk_status_t)11)
39
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40#define BLK_STS_AGAIN ((__force blk_status_t)12)
41
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42/*
43 * BLK_STS_DEV_RESOURCE is returned from the driver to the block layer if
44 * device related resources are unavailable, but the driver can guarantee
45 * that the queue will be rerun in the future once resources become
46 * available again. This is typically the case for device specific
47 * resources that are consumed for IO. If the driver fails allocating these
48 * resources, we know that inflight (or pending) IO will free these
49 * resource upon completion.
50 *
51 * This is different from BLK_STS_RESOURCE in that it explicitly references
52 * a device specific resource. For resources of wider scope, allocation
53 * failure can happen without having pending IO. This means that we can't
54 * rely on request completions freeing these resources, as IO may not be in
55 * flight. Examples of that are kernel memory allocations, DMA mappings, or
56 * any other system wide resources.
57 */
58#define BLK_STS_DEV_RESOURCE ((__force blk_status_t)13)
59
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60/**
61 * blk_path_error - returns true if error may be path related
62 * @error: status the request was completed with
63 *
64 * Description:
65 * This classifies block error status into non-retryable errors and ones
66 * that may be successful if retried on a failover path.
67 *
68 * Return:
69 * %false - retrying failover path will not help
70 * %true - may succeed if retried
71 */
72static inline bool blk_path_error(blk_status_t error)
73{
74 switch (error) {
75 case BLK_STS_NOTSUPP:
76 case BLK_STS_NOSPC:
77 case BLK_STS_TARGET:
78 case BLK_STS_NEXUS:
79 case BLK_STS_MEDIUM:
80 case BLK_STS_PROTECTION:
81 return false;
82 }
83
84 /* Anything else could be a path failure, so should be retried */
85 return true;
86}
87
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88struct blk_issue_stat {
89 u64 stat;
90};
91
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92/*
93 * main unit of I/O for the block layer and lower layers (ie drivers and
94 * stacking drivers)
95 */
96struct bio {
7cc01581 97 struct bio *bi_next; /* request queue link */
74d46992 98 struct gendisk *bi_disk;
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99 unsigned int bi_opf; /* bottom bits req flags,
100 * top bits REQ_OP. Use
101 * accessors.
4e1b2d52 102 */
dbde775c 103 unsigned short bi_flags; /* status, etc and bvec pool number */
43b62ce3 104 unsigned short bi_ioprio;
cb6934f8 105 unsigned short bi_write_hint;
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106 blk_status_t bi_status;
107 u8 bi_partno;
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108
109 /* Number of segments in this BIO after
110 * physical address coalescing is performed.
111 */
112 unsigned int bi_phys_segments;
113
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114 /*
115 * To keep track of the max segment size, we account for the
116 * sizes of the first and last mergeable segments in this bio.
117 */
118 unsigned int bi_seg_front_size;
119 unsigned int bi_seg_back_size;
120
111be883 121 struct bvec_iter bi_iter;
196d38bc 122
111be883 123 atomic_t __bi_remaining;
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124 bio_end_io_t *bi_end_io;
125
126 void *bi_private;
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127#ifdef CONFIG_BLK_CGROUP
128 /*
129 * Optional ioc and css associated with this bio. Put on bio
130 * release. Read comment on top of bio_associate_current().
131 */
132 struct io_context *bi_ioc;
133 struct cgroup_subsys_state *bi_css;
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134#ifdef CONFIG_BLK_DEV_THROTTLING_LOW
135 void *bi_cg_private;
b9147dd1 136 struct blk_issue_stat bi_issue_stat;
9e234eea 137#endif
852c788f 138#endif
180b2f95 139 union {
7cc01581 140#if defined(CONFIG_BLK_DEV_INTEGRITY)
180b2f95 141 struct bio_integrity_payload *bi_integrity; /* data integrity */
7cc01581 142#endif
180b2f95 143 };
7cc01581 144
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145 unsigned short bi_vcnt; /* how many bio_vec's */
146
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147 /*
148 * Everything starting with bi_max_vecs will be preserved by bio_reset()
149 */
150
4f024f37 151 unsigned short bi_max_vecs; /* max bvl_vecs we can hold */
f44b48c7 152
dac56212 153 atomic_t __bi_cnt; /* pin count */
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154
155 struct bio_vec *bi_io_vec; /* the actual vec list */
156
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157 struct bio_set *bi_pool;
158
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159 /*
160 * We can inline a number of vecs at the end of the bio, to avoid
161 * double allocations for a small number of bio_vecs. This member
162 * MUST obviously be kept at the very end of the bio.
163 */
164 struct bio_vec bi_inline_vecs[0];
165};
166
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167#define BIO_RESET_BYTES offsetof(struct bio, bi_max_vecs)
168
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169/*
170 * bio flags
171 */
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172#define BIO_SEG_VALID 1 /* bi_phys_segments valid */
173#define BIO_CLONED 2 /* doesn't own data */
174#define BIO_BOUNCED 3 /* bio is a bounce bio */
175#define BIO_USER_MAPPED 4 /* contains user pages */
176#define BIO_NULL_MAPPED 5 /* contains invalid user pages */
177#define BIO_QUIET 6 /* Make BIO Quiet */
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178#define BIO_CHAIN 7 /* chained bio, ->bi_remaining in effect */
179#define BIO_REFFED 8 /* bio has elevated ->bi_cnt */
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180#define BIO_THROTTLED 9 /* This bio has already been subjected to
181 * throttling rules. Don't do it again. */
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182#define BIO_TRACE_COMPLETION 10 /* bio_endio() should trace the final completion
183 * of this bio. */
dbde775c 184/* See BVEC_POOL_OFFSET below before adding new flags */
f44b48c7 185
7cc01581 186/*
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187 * We support 6 different bvec pools, the last one is magic in that it
188 * is backed by a mempool.
7cc01581 189 */
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190#define BVEC_POOL_NR 6
191#define BVEC_POOL_MAX (BVEC_POOL_NR - 1)
192
193/*
dbde775c 194 * Top 3 bits of bio flags indicate the pool the bvecs came from. We add
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195 * 1 to the actual index so that 0 indicates that there are no bvecs to be
196 * freed.
197 */
dbde775c 198#define BVEC_POOL_BITS (3)
c0acf12a 199#define BVEC_POOL_OFFSET (16 - BVEC_POOL_BITS)
ed996a52 200#define BVEC_POOL_IDX(bio) ((bio)->bi_flags >> BVEC_POOL_OFFSET)
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201#if (1<< BVEC_POOL_BITS) < (BVEC_POOL_NR+1)
202# error "BVEC_POOL_BITS is too small"
203#endif
204
205/*
206 * Flags starting here get preserved by bio_reset() - this includes
207 * only BVEC_POOL_IDX()
208 */
209#define BIO_RESET_BITS BVEC_POOL_OFFSET
7cc01581 210
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211typedef __u32 __bitwise blk_mq_req_flags_t;
212
7cc01581 213/*
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214 * Operations and flags common to the bio and request structures.
215 * We use 8 bits for encoding the operation, and the remaining 24 for flags.
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216 *
217 * The least significant bit of the operation number indicates the data
218 * transfer direction:
219 *
220 * - if the least significant bit is set transfers are TO the device
221 * - if the least significant bit is not set transfers are FROM the device
222 *
223 * If a operation does not transfer data the least significant bit has no
224 * meaning.
7cc01581 225 */
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226#define REQ_OP_BITS 8
227#define REQ_OP_MASK ((1 << REQ_OP_BITS) - 1)
228#define REQ_FLAG_BITS 24
229
230enum req_opf {
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231 /* read sectors from the device */
232 REQ_OP_READ = 0,
233 /* write sectors to the device */
234 REQ_OP_WRITE = 1,
235 /* flush the volatile write cache */
236 REQ_OP_FLUSH = 2,
237 /* discard sectors */
238 REQ_OP_DISCARD = 3,
239 /* get zone information */
240 REQ_OP_ZONE_REPORT = 4,
241 /* securely erase sectors */
242 REQ_OP_SECURE_ERASE = 5,
243 /* seset a zone write pointer */
244 REQ_OP_ZONE_RESET = 6,
245 /* write the same sector many times */
246 REQ_OP_WRITE_SAME = 7,
a6f0788e 247 /* write the zero filled sector many times */
1d62ac13 248 REQ_OP_WRITE_ZEROES = 9,
ef295ecf 249
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250 /* SCSI passthrough using struct scsi_request */
251 REQ_OP_SCSI_IN = 32,
252 REQ_OP_SCSI_OUT = 33,
253 /* Driver private requests */
254 REQ_OP_DRV_IN = 34,
255 REQ_OP_DRV_OUT = 35,
256
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257 REQ_OP_LAST,
258};
259
260enum req_flag_bits {
261 __REQ_FAILFAST_DEV = /* no driver retries of device errors */
262 REQ_OP_BITS,
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263 __REQ_FAILFAST_TRANSPORT, /* no driver retries of transport errors */
264 __REQ_FAILFAST_DRIVER, /* no driver retries of driver errors */
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265 __REQ_SYNC, /* request is sync (sync write or read) */
266 __REQ_META, /* metadata io request */
65299a3b 267 __REQ_PRIO, /* boost priority in cfq */
bd1c1c21 268 __REQ_NOMERGE, /* don't touch this for merging */
a2b80967 269 __REQ_IDLE, /* anticipate more IO after this one */
180b2f95 270 __REQ_INTEGRITY, /* I/O includes block integrity payload */
8e4bf844 271 __REQ_FUA, /* forced unit access */
28a8f0d3 272 __REQ_PREFLUSH, /* request for cache flush */
188bd2b1 273 __REQ_RAHEAD, /* read ahead, can fail anytime */
1d796d6a 274 __REQ_BACKGROUND, /* background IO */
8977f563 275 __REQ_NOWAIT, /* Don't wait if request will block */
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276
277 /* command specific flags for REQ_OP_WRITE_ZEROES: */
278 __REQ_NOUNMAP, /* do not free blocks when zeroing */
279
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280 /* for driver use */
281 __REQ_DRV,
282
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283 __REQ_NR_BITS, /* stops here */
284};
285
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286#define REQ_FAILFAST_DEV (1ULL << __REQ_FAILFAST_DEV)
287#define REQ_FAILFAST_TRANSPORT (1ULL << __REQ_FAILFAST_TRANSPORT)
288#define REQ_FAILFAST_DRIVER (1ULL << __REQ_FAILFAST_DRIVER)
289#define REQ_SYNC (1ULL << __REQ_SYNC)
290#define REQ_META (1ULL << __REQ_META)
291#define REQ_PRIO (1ULL << __REQ_PRIO)
ef295ecf 292#define REQ_NOMERGE (1ULL << __REQ_NOMERGE)
a2b80967 293#define REQ_IDLE (1ULL << __REQ_IDLE)
180b2f95 294#define REQ_INTEGRITY (1ULL << __REQ_INTEGRITY)
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295#define REQ_FUA (1ULL << __REQ_FUA)
296#define REQ_PREFLUSH (1ULL << __REQ_PREFLUSH)
297#define REQ_RAHEAD (1ULL << __REQ_RAHEAD)
1d796d6a 298#define REQ_BACKGROUND (1ULL << __REQ_BACKGROUND)
8977f563 299#define REQ_NOWAIT (1ULL << __REQ_NOWAIT)
7cc01581 300
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301#define REQ_NOUNMAP (1ULL << __REQ_NOUNMAP)
302
96222bcc 303#define REQ_DRV (1ULL << __REQ_DRV)
d928be9f 304
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305#define REQ_FAILFAST_MASK \
306 (REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT | REQ_FAILFAST_DRIVER)
7cc01581 307
e2a60da7 308#define REQ_NOMERGE_FLAGS \
e8064021 309 (REQ_NOMERGE | REQ_PREFLUSH | REQ_FUA)
e2a60da7 310
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311#define bio_op(bio) \
312 ((bio)->bi_opf & REQ_OP_MASK)
313#define req_op(req) \
314 ((req)->cmd_flags & REQ_OP_MASK)
7cc01581 315
ef295ecf 316/* obsolete, don't use in new code */
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317static inline void bio_set_op_attrs(struct bio *bio, unsigned op,
318 unsigned op_flags)
319{
320 bio->bi_opf = op | op_flags;
321}
c11f0c0b 322
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323static inline bool op_is_write(unsigned int op)
324{
325 return (op & 1);
326}
327
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328/*
329 * Check if the bio or request is one that needs special treatment in the
330 * flush state machine.
331 */
332static inline bool op_is_flush(unsigned int op)
333{
334 return op & (REQ_FUA | REQ_PREFLUSH);
335}
336
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337/*
338 * Reads are always treated as synchronous, as are requests with the FUA or
339 * PREFLUSH flag. Other operations may be marked as synchronous using the
340 * REQ_SYNC flag.
341 */
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342static inline bool op_is_sync(unsigned int op)
343{
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344 return (op & REQ_OP_MASK) == REQ_OP_READ ||
345 (op & (REQ_SYNC | REQ_FUA | REQ_PREFLUSH));
ef295ecf 346}
c11f0c0b 347
dece1635 348typedef unsigned int blk_qc_t;
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349#define BLK_QC_T_NONE -1U
350#define BLK_QC_T_SHIFT 16
351#define BLK_QC_T_INTERNAL (1U << 31)
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352
353static inline bool blk_qc_t_valid(blk_qc_t cookie)
354{
355 return cookie != BLK_QC_T_NONE;
356}
357
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358static inline blk_qc_t blk_tag_to_qc_t(unsigned int tag, unsigned int queue_num,
359 bool internal)
dece1635 360{
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361 blk_qc_t ret = tag | (queue_num << BLK_QC_T_SHIFT);
362
363 if (internal)
364 ret |= BLK_QC_T_INTERNAL;
365
366 return ret;
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367}
368
369static inline unsigned int blk_qc_t_to_queue_num(blk_qc_t cookie)
370{
fd2d3326 371 return (cookie & ~BLK_QC_T_INTERNAL) >> BLK_QC_T_SHIFT;
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372}
373
374static inline unsigned int blk_qc_t_to_tag(blk_qc_t cookie)
375{
e3a7a3bf 376 return cookie & ((1u << BLK_QC_T_SHIFT) - 1);
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377}
378
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379static inline bool blk_qc_t_is_internal(blk_qc_t cookie)
380{
381 return (cookie & BLK_QC_T_INTERNAL) != 0;
382}
383
cf43e6be 384struct blk_rq_stat {
eca8b53a 385 u64 mean;
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386 u64 min;
387 u64 max;
eca8b53a 388 u32 nr_samples;
cf43e6be 389 u64 batch;
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390};
391
7cc01581 392#endif /* __LINUX_BLK_TYPES_H */