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1 | /* | |
2 | * Block data types and constants. Directly include this file only to | |
3 | * break include dependency loop. | |
4 | */ | |
5 | #ifndef __LINUX_BLK_TYPES_H | |
6 | #define __LINUX_BLK_TYPES_H | |
7 | ||
8 | #include <linux/types.h> | |
9 | #include <linux/bvec.h> | |
10 | ||
11 | struct bio_set; | |
12 | struct bio; | |
13 | struct bio_integrity_payload; | |
14 | struct page; | |
15 | struct block_device; | |
16 | struct io_context; | |
17 | struct cgroup_subsys_state; | |
18 | typedef void (bio_end_io_t) (struct bio *); | |
19 | ||
20 | #ifdef CONFIG_BLOCK | |
21 | /* | |
22 | * main unit of I/O for the block layer and lower layers (ie drivers and | |
23 | * stacking drivers) | |
24 | */ | |
25 | struct bio { | |
26 | struct bio *bi_next; /* request queue link */ | |
27 | struct block_device *bi_bdev; | |
28 | int bi_error; | |
29 | unsigned int bi_opf; /* bottom bits req flags, | |
30 | * top bits REQ_OP. Use | |
31 | * accessors. | |
32 | */ | |
33 | unsigned short bi_flags; /* status, command, etc */ | |
34 | unsigned short bi_ioprio; | |
35 | ||
36 | struct bvec_iter bi_iter; | |
37 | ||
38 | /* Number of segments in this BIO after | |
39 | * physical address coalescing is performed. | |
40 | */ | |
41 | unsigned int bi_phys_segments; | |
42 | ||
43 | /* | |
44 | * To keep track of the max segment size, we account for the | |
45 | * sizes of the first and last mergeable segments in this bio. | |
46 | */ | |
47 | unsigned int bi_seg_front_size; | |
48 | unsigned int bi_seg_back_size; | |
49 | ||
50 | atomic_t __bi_remaining; | |
51 | ||
52 | bio_end_io_t *bi_end_io; | |
53 | ||
54 | void *bi_private; | |
55 | #ifdef CONFIG_BLK_CGROUP | |
56 | /* | |
57 | * Optional ioc and css associated with this bio. Put on bio | |
58 | * release. Read comment on top of bio_associate_current(). | |
59 | */ | |
60 | struct io_context *bi_ioc; | |
61 | struct cgroup_subsys_state *bi_css; | |
62 | #endif | |
63 | union { | |
64 | #if defined(CONFIG_BLK_DEV_INTEGRITY) | |
65 | struct bio_integrity_payload *bi_integrity; /* data integrity */ | |
66 | #endif | |
67 | }; | |
68 | ||
69 | unsigned short bi_vcnt; /* how many bio_vec's */ | |
70 | ||
71 | /* | |
72 | * Everything starting with bi_max_vecs will be preserved by bio_reset() | |
73 | */ | |
74 | ||
75 | unsigned short bi_max_vecs; /* max bvl_vecs we can hold */ | |
76 | ||
77 | atomic_t __bi_cnt; /* pin count */ | |
78 | ||
79 | struct bio_vec *bi_io_vec; /* the actual vec list */ | |
80 | ||
81 | struct bio_set *bi_pool; | |
82 | ||
83 | /* | |
84 | * We can inline a number of vecs at the end of the bio, to avoid | |
85 | * double allocations for a small number of bio_vecs. This member | |
86 | * MUST obviously be kept at the very end of the bio. | |
87 | */ | |
88 | struct bio_vec bi_inline_vecs[0]; | |
89 | }; | |
90 | ||
91 | #define BIO_OP_SHIFT (8 * FIELD_SIZEOF(struct bio, bi_opf) - REQ_OP_BITS) | |
92 | #define bio_flags(bio) ((bio)->bi_opf & ((1 << BIO_OP_SHIFT) - 1)) | |
93 | #define bio_op(bio) ((bio)->bi_opf >> BIO_OP_SHIFT) | |
94 | ||
95 | #define bio_set_op_attrs(bio, op, op_flags) do { \ | |
96 | if (__builtin_constant_p(op)) \ | |
97 | BUILD_BUG_ON((op) + 0U >= (1U << REQ_OP_BITS)); \ | |
98 | else \ | |
99 | WARN_ON_ONCE((op) + 0U >= (1U << REQ_OP_BITS)); \ | |
100 | if (__builtin_constant_p(op_flags)) \ | |
101 | BUILD_BUG_ON((op_flags) + 0U >= (1U << BIO_OP_SHIFT)); \ | |
102 | else \ | |
103 | WARN_ON_ONCE((op_flags) + 0U >= (1U << BIO_OP_SHIFT)); \ | |
104 | (bio)->bi_opf = bio_flags(bio); \ | |
105 | (bio)->bi_opf |= (((op) + 0U) << BIO_OP_SHIFT); \ | |
106 | (bio)->bi_opf |= (op_flags); \ | |
107 | } while (0) | |
108 | ||
109 | #define BIO_RESET_BYTES offsetof(struct bio, bi_max_vecs) | |
110 | ||
111 | /* | |
112 | * bio flags | |
113 | */ | |
114 | #define BIO_SEG_VALID 1 /* bi_phys_segments valid */ | |
115 | #define BIO_CLONED 2 /* doesn't own data */ | |
116 | #define BIO_BOUNCED 3 /* bio is a bounce bio */ | |
117 | #define BIO_USER_MAPPED 4 /* contains user pages */ | |
118 | #define BIO_NULL_MAPPED 5 /* contains invalid user pages */ | |
119 | #define BIO_QUIET 6 /* Make BIO Quiet */ | |
120 | #define BIO_CHAIN 7 /* chained bio, ->bi_remaining in effect */ | |
121 | #define BIO_REFFED 8 /* bio has elevated ->bi_cnt */ | |
122 | ||
123 | /* | |
124 | * Flags starting here get preserved by bio_reset() - this includes | |
125 | * BVEC_POOL_IDX() | |
126 | */ | |
127 | #define BIO_RESET_BITS 10 | |
128 | ||
129 | /* | |
130 | * We support 6 different bvec pools, the last one is magic in that it | |
131 | * is backed by a mempool. | |
132 | */ | |
133 | #define BVEC_POOL_NR 6 | |
134 | #define BVEC_POOL_MAX (BVEC_POOL_NR - 1) | |
135 | ||
136 | /* | |
137 | * Top 4 bits of bio flags indicate the pool the bvecs came from. We add | |
138 | * 1 to the actual index so that 0 indicates that there are no bvecs to be | |
139 | * freed. | |
140 | */ | |
141 | #define BVEC_POOL_BITS (4) | |
142 | #define BVEC_POOL_OFFSET (16 - BVEC_POOL_BITS) | |
143 | #define BVEC_POOL_IDX(bio) ((bio)->bi_flags >> BVEC_POOL_OFFSET) | |
144 | ||
145 | #endif /* CONFIG_BLOCK */ | |
146 | ||
147 | /* | |
148 | * Request flags. For use in the cmd_flags field of struct request, and in | |
149 | * bi_opf of struct bio. Note that some flags are only valid in either one. | |
150 | */ | |
151 | enum rq_flag_bits { | |
152 | /* common flags */ | |
153 | __REQ_FAILFAST_DEV, /* no driver retries of device errors */ | |
154 | __REQ_FAILFAST_TRANSPORT, /* no driver retries of transport errors */ | |
155 | __REQ_FAILFAST_DRIVER, /* no driver retries of driver errors */ | |
156 | ||
157 | __REQ_SYNC, /* request is sync (sync write or read) */ | |
158 | __REQ_META, /* metadata io request */ | |
159 | __REQ_PRIO, /* boost priority in cfq */ | |
160 | ||
161 | __REQ_NOIDLE, /* don't anticipate more IO after this one */ | |
162 | __REQ_INTEGRITY, /* I/O includes block integrity payload */ | |
163 | __REQ_FUA, /* forced unit access */ | |
164 | __REQ_PREFLUSH, /* request for cache flush */ | |
165 | ||
166 | /* bio only flags */ | |
167 | __REQ_RAHEAD, /* read ahead, can fail anytime */ | |
168 | __REQ_THROTTLED, /* This bio has already been subjected to | |
169 | * throttling rules. Don't do it again. */ | |
170 | ||
171 | /* request only flags */ | |
172 | __REQ_SORTED, /* elevator knows about this request */ | |
173 | __REQ_SOFTBARRIER, /* may not be passed by ioscheduler */ | |
174 | __REQ_NOMERGE, /* don't touch this for merging */ | |
175 | __REQ_STARTED, /* drive already may have started this one */ | |
176 | __REQ_DONTPREP, /* don't call prep for this one */ | |
177 | __REQ_QUEUED, /* uses queueing */ | |
178 | __REQ_ELVPRIV, /* elevator private data attached */ | |
179 | __REQ_FAILED, /* set if the request failed */ | |
180 | __REQ_QUIET, /* don't worry about errors */ | |
181 | __REQ_PREEMPT, /* set for "ide_preempt" requests and also | |
182 | for requests for which the SCSI "quiesce" | |
183 | state must be ignored. */ | |
184 | __REQ_ALLOCED, /* request came from our alloc pool */ | |
185 | __REQ_COPY_USER, /* contains copies of user pages */ | |
186 | __REQ_FLUSH_SEQ, /* request for flush sequence */ | |
187 | __REQ_IO_STAT, /* account I/O stat */ | |
188 | __REQ_MIXED_MERGE, /* merge of different types, fail separately */ | |
189 | __REQ_PM, /* runtime pm request */ | |
190 | __REQ_HASHED, /* on IO scheduler merge hash */ | |
191 | __REQ_MQ_INFLIGHT, /* track inflight for MQ */ | |
192 | __REQ_NR_BITS, /* stops here */ | |
193 | }; | |
194 | ||
195 | #define REQ_FAILFAST_DEV (1ULL << __REQ_FAILFAST_DEV) | |
196 | #define REQ_FAILFAST_TRANSPORT (1ULL << __REQ_FAILFAST_TRANSPORT) | |
197 | #define REQ_FAILFAST_DRIVER (1ULL << __REQ_FAILFAST_DRIVER) | |
198 | #define REQ_SYNC (1ULL << __REQ_SYNC) | |
199 | #define REQ_META (1ULL << __REQ_META) | |
200 | #define REQ_PRIO (1ULL << __REQ_PRIO) | |
201 | #define REQ_NOIDLE (1ULL << __REQ_NOIDLE) | |
202 | #define REQ_INTEGRITY (1ULL << __REQ_INTEGRITY) | |
203 | ||
204 | #define REQ_FAILFAST_MASK \ | |
205 | (REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT | REQ_FAILFAST_DRIVER) | |
206 | #define REQ_COMMON_MASK \ | |
207 | (REQ_FAILFAST_MASK | REQ_SYNC | REQ_META | REQ_PRIO | REQ_NOIDLE | \ | |
208 | REQ_PREFLUSH | REQ_FUA | REQ_INTEGRITY | REQ_NOMERGE) | |
209 | #define REQ_CLONE_MASK REQ_COMMON_MASK | |
210 | ||
211 | /* This mask is used for both bio and request merge checking */ | |
212 | #define REQ_NOMERGE_FLAGS \ | |
213 | (REQ_NOMERGE | REQ_STARTED | REQ_SOFTBARRIER | REQ_PREFLUSH | REQ_FUA | REQ_FLUSH_SEQ) | |
214 | ||
215 | #define REQ_RAHEAD (1ULL << __REQ_RAHEAD) | |
216 | #define REQ_THROTTLED (1ULL << __REQ_THROTTLED) | |
217 | ||
218 | #define REQ_SORTED (1ULL << __REQ_SORTED) | |
219 | #define REQ_SOFTBARRIER (1ULL << __REQ_SOFTBARRIER) | |
220 | #define REQ_FUA (1ULL << __REQ_FUA) | |
221 | #define REQ_NOMERGE (1ULL << __REQ_NOMERGE) | |
222 | #define REQ_STARTED (1ULL << __REQ_STARTED) | |
223 | #define REQ_DONTPREP (1ULL << __REQ_DONTPREP) | |
224 | #define REQ_QUEUED (1ULL << __REQ_QUEUED) | |
225 | #define REQ_ELVPRIV (1ULL << __REQ_ELVPRIV) | |
226 | #define REQ_FAILED (1ULL << __REQ_FAILED) | |
227 | #define REQ_QUIET (1ULL << __REQ_QUIET) | |
228 | #define REQ_PREEMPT (1ULL << __REQ_PREEMPT) | |
229 | #define REQ_ALLOCED (1ULL << __REQ_ALLOCED) | |
230 | #define REQ_COPY_USER (1ULL << __REQ_COPY_USER) | |
231 | #define REQ_PREFLUSH (1ULL << __REQ_PREFLUSH) | |
232 | #define REQ_FLUSH_SEQ (1ULL << __REQ_FLUSH_SEQ) | |
233 | #define REQ_IO_STAT (1ULL << __REQ_IO_STAT) | |
234 | #define REQ_MIXED_MERGE (1ULL << __REQ_MIXED_MERGE) | |
235 | #define REQ_PM (1ULL << __REQ_PM) | |
236 | #define REQ_HASHED (1ULL << __REQ_HASHED) | |
237 | #define REQ_MQ_INFLIGHT (1ULL << __REQ_MQ_INFLIGHT) | |
238 | ||
239 | enum req_op { | |
240 | REQ_OP_READ, | |
241 | REQ_OP_WRITE, | |
242 | REQ_OP_DISCARD, /* request to discard sectors */ | |
243 | REQ_OP_SECURE_ERASE, /* request to securely erase sectors */ | |
244 | REQ_OP_WRITE_SAME, /* write same block many times */ | |
245 | REQ_OP_FLUSH, /* request for cache flush */ | |
246 | REQ_OP_ZONE_REPORT, /* Get zone information */ | |
247 | REQ_OP_ZONE_RESET, /* Reset a zone write pointer */ | |
248 | }; | |
249 | ||
250 | #define REQ_OP_BITS 3 | |
251 | ||
252 | typedef unsigned int blk_qc_t; | |
253 | #define BLK_QC_T_NONE -1U | |
254 | #define BLK_QC_T_SHIFT 16 | |
255 | ||
256 | static inline bool blk_qc_t_valid(blk_qc_t cookie) | |
257 | { | |
258 | return cookie != BLK_QC_T_NONE; | |
259 | } | |
260 | ||
261 | static inline blk_qc_t blk_tag_to_qc_t(unsigned int tag, unsigned int queue_num) | |
262 | { | |
263 | return tag | (queue_num << BLK_QC_T_SHIFT); | |
264 | } | |
265 | ||
266 | static inline unsigned int blk_qc_t_to_queue_num(blk_qc_t cookie) | |
267 | { | |
268 | return cookie >> BLK_QC_T_SHIFT; | |
269 | } | |
270 | ||
271 | static inline unsigned int blk_qc_t_to_tag(blk_qc_t cookie) | |
272 | { | |
273 | return cookie & ((1u << BLK_QC_T_SHIFT) - 1); | |
274 | } | |
275 | ||
276 | #endif /* __LINUX_BLK_TYPES_H */ |