Tejun Heo | 7cc0158 | 2010-08-03 13:14:58 +0200 | [diff] [blame] | 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 | #ifdef CONFIG_BLOCK |
| 9 | |
| 10 | #include <linux/types.h> |
| 11 | |
| 12 | struct bio_set; |
| 13 | struct bio; |
| 14 | struct bio_integrity_payload; |
| 15 | struct page; |
| 16 | struct block_device; |
| 17 | typedef void (bio_end_io_t) (struct bio *, int); |
| 18 | typedef void (bio_destructor_t) (struct bio *); |
| 19 | |
| 20 | /* |
| 21 | * was unsigned short, but we might as well be ready for > 64kB I/O pages |
| 22 | */ |
| 23 | struct bio_vec { |
| 24 | struct page *bv_page; |
| 25 | unsigned int bv_len; |
| 26 | unsigned int bv_offset; |
| 27 | }; |
| 28 | |
| 29 | /* |
| 30 | * main unit of I/O for the block layer and lower layers (ie drivers and |
| 31 | * stacking drivers) |
| 32 | */ |
| 33 | struct bio { |
| 34 | sector_t bi_sector; /* device address in 512 byte |
| 35 | sectors */ |
| 36 | struct bio *bi_next; /* request queue link */ |
| 37 | struct block_device *bi_bdev; |
| 38 | unsigned long bi_flags; /* status, command, etc */ |
| 39 | unsigned long bi_rw; /* bottom bits READ/WRITE, |
| 40 | * top bits priority |
| 41 | */ |
| 42 | |
| 43 | unsigned short bi_vcnt; /* how many bio_vec's */ |
| 44 | unsigned short bi_idx; /* current index into bvl_vec */ |
| 45 | |
| 46 | /* Number of segments in this BIO after |
| 47 | * physical address coalescing is performed. |
| 48 | */ |
| 49 | unsigned int bi_phys_segments; |
| 50 | |
| 51 | unsigned int bi_size; /* residual I/O count */ |
| 52 | |
| 53 | /* |
| 54 | * To keep track of the max segment size, we account for the |
| 55 | * sizes of the first and last mergeable segments in this bio. |
| 56 | */ |
| 57 | unsigned int bi_seg_front_size; |
| 58 | unsigned int bi_seg_back_size; |
| 59 | |
| 60 | unsigned int bi_max_vecs; /* max bvl_vecs we can hold */ |
| 61 | |
| 62 | unsigned int bi_comp_cpu; /* completion CPU */ |
| 63 | |
| 64 | atomic_t bi_cnt; /* pin count */ |
| 65 | |
| 66 | struct bio_vec *bi_io_vec; /* the actual vec list */ |
| 67 | |
| 68 | bio_end_io_t *bi_end_io; |
| 69 | |
| 70 | void *bi_private; |
| 71 | #if defined(CONFIG_BLK_DEV_INTEGRITY) |
| 72 | struct bio_integrity_payload *bi_integrity; /* data integrity */ |
| 73 | #endif |
| 74 | |
| 75 | bio_destructor_t *bi_destructor; /* destructor */ |
| 76 | |
| 77 | /* |
| 78 | * We can inline a number of vecs at the end of the bio, to avoid |
| 79 | * double allocations for a small number of bio_vecs. This member |
| 80 | * MUST obviously be kept at the very end of the bio. |
| 81 | */ |
| 82 | struct bio_vec bi_inline_vecs[0]; |
| 83 | }; |
| 84 | |
| 85 | /* |
| 86 | * bio flags |
| 87 | */ |
| 88 | #define BIO_UPTODATE 0 /* ok after I/O completion */ |
| 89 | #define BIO_RW_BLOCK 1 /* RW_AHEAD set, and read/write would block */ |
| 90 | #define BIO_EOF 2 /* out-out-bounds error */ |
| 91 | #define BIO_SEG_VALID 3 /* bi_phys_segments valid */ |
| 92 | #define BIO_CLONED 4 /* doesn't own data */ |
| 93 | #define BIO_BOUNCED 5 /* bio is a bounce bio */ |
| 94 | #define BIO_USER_MAPPED 6 /* contains user pages */ |
| 95 | #define BIO_EOPNOTSUPP 7 /* not supported */ |
| 96 | #define BIO_CPU_AFFINE 8 /* complete bio on same CPU as submitted */ |
| 97 | #define BIO_NULL_MAPPED 9 /* contains invalid user pages */ |
| 98 | #define BIO_FS_INTEGRITY 10 /* fs owns integrity data, not block layer */ |
| 99 | #define BIO_QUIET 11 /* Make BIO Quiet */ |
Martin K. Petersen | 495d2b3 | 2010-10-15 15:49:20 +0200 | [diff] [blame] | 100 | #define BIO_MAPPED_INTEGRITY 12/* integrity metadata has been remapped */ |
Tejun Heo | 7cc0158 | 2010-08-03 13:14:58 +0200 | [diff] [blame] | 101 | #define bio_flagged(bio, flag) ((bio)->bi_flags & (1 << (flag))) |
| 102 | |
| 103 | /* |
| 104 | * top 4 bits of bio flags indicate the pool this bio came from |
| 105 | */ |
| 106 | #define BIO_POOL_BITS (4) |
| 107 | #define BIO_POOL_NONE ((1UL << BIO_POOL_BITS) - 1) |
| 108 | #define BIO_POOL_OFFSET (BITS_PER_LONG - BIO_POOL_BITS) |
| 109 | #define BIO_POOL_MASK (1UL << BIO_POOL_OFFSET) |
| 110 | #define BIO_POOL_IDX(bio) ((bio)->bi_flags >> BIO_POOL_OFFSET) |
| 111 | |
Jens Axboe | de75d60 | 2010-08-10 12:14:27 -0400 | [diff] [blame] | 112 | #endif /* CONFIG_BLOCK */ |
| 113 | |
Tejun Heo | 7cc0158 | 2010-08-03 13:14:58 +0200 | [diff] [blame] | 114 | /* |
| 115 | * Request flags. For use in the cmd_flags field of struct request, and in |
| 116 | * bi_rw of struct bio. Note that some flags are only valid in either one. |
| 117 | */ |
| 118 | enum rq_flag_bits { |
| 119 | /* common flags */ |
| 120 | __REQ_WRITE, /* not set, read. set, write */ |
| 121 | __REQ_FAILFAST_DEV, /* no driver retries of device errors */ |
| 122 | __REQ_FAILFAST_TRANSPORT, /* no driver retries of transport errors */ |
| 123 | __REQ_FAILFAST_DRIVER, /* no driver retries of driver errors */ |
| 124 | |
Tejun Heo | 7cc0158 | 2010-08-03 13:14:58 +0200 | [diff] [blame] | 125 | __REQ_SYNC, /* request is sync (sync write or read) */ |
| 126 | __REQ_META, /* metadata io request */ |
| 127 | __REQ_DISCARD, /* request to discard sectors */ |
| 128 | __REQ_NOIDLE, /* don't anticipate more IO after this one */ |
| 129 | |
| 130 | /* bio only flags */ |
| 131 | __REQ_UNPLUG, /* unplug the immediately after submission */ |
| 132 | __REQ_RAHEAD, /* read ahead, can fail anytime */ |
Vivek Goyal | e43473b | 2010-09-15 17:06:35 -0400 | [diff] [blame] | 133 | __REQ_THROTTLED, /* This bio has already been subjected to |
| 134 | * throttling rules. Don't do it again. */ |
Tejun Heo | 7cc0158 | 2010-08-03 13:14:58 +0200 | [diff] [blame] | 135 | |
| 136 | /* request only flags */ |
| 137 | __REQ_SORTED, /* elevator knows about this request */ |
| 138 | __REQ_SOFTBARRIER, /* may not be passed by ioscheduler */ |
| 139 | __REQ_FUA, /* forced unit access */ |
| 140 | __REQ_NOMERGE, /* don't touch this for merging */ |
| 141 | __REQ_STARTED, /* drive already may have started this one */ |
| 142 | __REQ_DONTPREP, /* don't call prep for this one */ |
| 143 | __REQ_QUEUED, /* uses queueing */ |
| 144 | __REQ_ELVPRIV, /* elevator private data attached */ |
| 145 | __REQ_FAILED, /* set if the request failed */ |
| 146 | __REQ_QUIET, /* don't worry about errors */ |
| 147 | __REQ_PREEMPT, /* set for "ide_preempt" requests */ |
Tejun Heo | 7cc0158 | 2010-08-03 13:14:58 +0200 | [diff] [blame] | 148 | __REQ_ALLOCED, /* request came from our alloc pool */ |
| 149 | __REQ_COPY_USER, /* contains copies of user pages */ |
Tejun Heo | 7cc0158 | 2010-08-03 13:14:58 +0200 | [diff] [blame] | 150 | __REQ_FLUSH, /* request for cache flush */ |
Tejun Heo | 414b4ff | 2011-01-25 12:43:49 +0100 | [diff] [blame^] | 151 | __REQ_FLUSH_SEQ, /* request for flush sequence */ |
Tejun Heo | 7cc0158 | 2010-08-03 13:14:58 +0200 | [diff] [blame] | 152 | __REQ_IO_STAT, /* account I/O stat */ |
| 153 | __REQ_MIXED_MERGE, /* merge of different types, fail separately */ |
Adrian Hunter | 8d57a98 | 2010-08-11 14:17:49 -0700 | [diff] [blame] | 154 | __REQ_SECURE, /* secure discard (used with __REQ_DISCARD) */ |
Tejun Heo | 7cc0158 | 2010-08-03 13:14:58 +0200 | [diff] [blame] | 155 | __REQ_NR_BITS, /* stops here */ |
| 156 | }; |
| 157 | |
| 158 | #define REQ_WRITE (1 << __REQ_WRITE) |
| 159 | #define REQ_FAILFAST_DEV (1 << __REQ_FAILFAST_DEV) |
| 160 | #define REQ_FAILFAST_TRANSPORT (1 << __REQ_FAILFAST_TRANSPORT) |
| 161 | #define REQ_FAILFAST_DRIVER (1 << __REQ_FAILFAST_DRIVER) |
Tejun Heo | 7cc0158 | 2010-08-03 13:14:58 +0200 | [diff] [blame] | 162 | #define REQ_SYNC (1 << __REQ_SYNC) |
| 163 | #define REQ_META (1 << __REQ_META) |
| 164 | #define REQ_DISCARD (1 << __REQ_DISCARD) |
| 165 | #define REQ_NOIDLE (1 << __REQ_NOIDLE) |
| 166 | |
| 167 | #define REQ_FAILFAST_MASK \ |
| 168 | (REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT | REQ_FAILFAST_DRIVER) |
| 169 | #define REQ_COMMON_MASK \ |
Christoph Hellwig | 02e031c | 2010-11-10 14:54:09 +0100 | [diff] [blame] | 170 | (REQ_WRITE | REQ_FAILFAST_MASK | REQ_SYNC | REQ_META | REQ_DISCARD | \ |
| 171 | REQ_NOIDLE | REQ_FLUSH | REQ_FUA) |
Tejun Heo | 3a2edd0 | 2010-09-03 11:56:18 +0200 | [diff] [blame] | 172 | #define REQ_CLONE_MASK REQ_COMMON_MASK |
Tejun Heo | 7cc0158 | 2010-08-03 13:14:58 +0200 | [diff] [blame] | 173 | |
| 174 | #define REQ_UNPLUG (1 << __REQ_UNPLUG) |
| 175 | #define REQ_RAHEAD (1 << __REQ_RAHEAD) |
Vivek Goyal | e43473b | 2010-09-15 17:06:35 -0400 | [diff] [blame] | 176 | #define REQ_THROTTLED (1 << __REQ_THROTTLED) |
Tejun Heo | 7cc0158 | 2010-08-03 13:14:58 +0200 | [diff] [blame] | 177 | |
| 178 | #define REQ_SORTED (1 << __REQ_SORTED) |
| 179 | #define REQ_SOFTBARRIER (1 << __REQ_SOFTBARRIER) |
| 180 | #define REQ_FUA (1 << __REQ_FUA) |
| 181 | #define REQ_NOMERGE (1 << __REQ_NOMERGE) |
| 182 | #define REQ_STARTED (1 << __REQ_STARTED) |
| 183 | #define REQ_DONTPREP (1 << __REQ_DONTPREP) |
| 184 | #define REQ_QUEUED (1 << __REQ_QUEUED) |
| 185 | #define REQ_ELVPRIV (1 << __REQ_ELVPRIV) |
| 186 | #define REQ_FAILED (1 << __REQ_FAILED) |
| 187 | #define REQ_QUIET (1 << __REQ_QUIET) |
| 188 | #define REQ_PREEMPT (1 << __REQ_PREEMPT) |
Tejun Heo | 7cc0158 | 2010-08-03 13:14:58 +0200 | [diff] [blame] | 189 | #define REQ_ALLOCED (1 << __REQ_ALLOCED) |
| 190 | #define REQ_COPY_USER (1 << __REQ_COPY_USER) |
Tejun Heo | 7cc0158 | 2010-08-03 13:14:58 +0200 | [diff] [blame] | 191 | #define REQ_FLUSH (1 << __REQ_FLUSH) |
Tejun Heo | 414b4ff | 2011-01-25 12:43:49 +0100 | [diff] [blame^] | 192 | #define REQ_FLUSH_SEQ (1 << __REQ_FLUSH_SEQ) |
Tejun Heo | 7cc0158 | 2010-08-03 13:14:58 +0200 | [diff] [blame] | 193 | #define REQ_IO_STAT (1 << __REQ_IO_STAT) |
| 194 | #define REQ_MIXED_MERGE (1 << __REQ_MIXED_MERGE) |
Adrian Hunter | 8d57a98 | 2010-08-11 14:17:49 -0700 | [diff] [blame] | 195 | #define REQ_SECURE (1 << __REQ_SECURE) |
Tejun Heo | 7cc0158 | 2010-08-03 13:14:58 +0200 | [diff] [blame] | 196 | |
Tejun Heo | 7cc0158 | 2010-08-03 13:14:58 +0200 | [diff] [blame] | 197 | #endif /* __LINUX_BLK_TYPES_H */ |