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; |
Tejun Heo | 852c788 | 2012-03-05 13:15:27 -0800 | [diff] [blame] | 17 | struct io_context; |
| 18 | struct cgroup_subsys_state; |
Tejun Heo | 7cc0158 | 2010-08-03 13:14:58 +0200 | [diff] [blame] | 19 | typedef void (bio_end_io_t) (struct bio *, int); |
| 20 | typedef void (bio_destructor_t) (struct bio *); |
| 21 | |
| 22 | /* |
| 23 | * was unsigned short, but we might as well be ready for > 64kB I/O pages |
| 24 | */ |
| 25 | struct bio_vec { |
| 26 | struct page *bv_page; |
| 27 | unsigned int bv_len; |
| 28 | unsigned int bv_offset; |
| 29 | }; |
| 30 | |
| 31 | /* |
| 32 | * main unit of I/O for the block layer and lower layers (ie drivers and |
| 33 | * stacking drivers) |
| 34 | */ |
| 35 | struct bio { |
| 36 | sector_t bi_sector; /* device address in 512 byte |
| 37 | sectors */ |
| 38 | struct bio *bi_next; /* request queue link */ |
| 39 | struct block_device *bi_bdev; |
| 40 | unsigned long bi_flags; /* status, command, etc */ |
| 41 | unsigned long bi_rw; /* bottom bits READ/WRITE, |
| 42 | * top bits priority |
| 43 | */ |
| 44 | |
| 45 | unsigned short bi_vcnt; /* how many bio_vec's */ |
| 46 | unsigned short bi_idx; /* current index into bvl_vec */ |
| 47 | |
| 48 | /* Number of segments in this BIO after |
| 49 | * physical address coalescing is performed. |
| 50 | */ |
| 51 | unsigned int bi_phys_segments; |
| 52 | |
| 53 | unsigned int bi_size; /* residual I/O count */ |
| 54 | |
| 55 | /* |
| 56 | * To keep track of the max segment size, we account for the |
| 57 | * sizes of the first and last mergeable segments in this bio. |
| 58 | */ |
| 59 | unsigned int bi_seg_front_size; |
| 60 | unsigned int bi_seg_back_size; |
| 61 | |
Tejun Heo | 7cc0158 | 2010-08-03 13:14:58 +0200 | [diff] [blame] | 62 | bio_end_io_t *bi_end_io; |
| 63 | |
| 64 | void *bi_private; |
Tejun Heo | 852c788 | 2012-03-05 13:15:27 -0800 | [diff] [blame] | 65 | #ifdef CONFIG_BLK_CGROUP |
| 66 | /* |
| 67 | * Optional ioc and css associated with this bio. Put on bio |
| 68 | * release. Read comment on top of bio_associate_current(). |
| 69 | */ |
| 70 | struct io_context *bi_ioc; |
| 71 | struct cgroup_subsys_state *bi_css; |
| 72 | #endif |
Tejun Heo | 7cc0158 | 2010-08-03 13:14:58 +0200 | [diff] [blame] | 73 | #if defined(CONFIG_BLK_DEV_INTEGRITY) |
| 74 | struct bio_integrity_payload *bi_integrity; /* data integrity */ |
| 75 | #endif |
| 76 | |
Kent Overstreet | f44b48c | 2012-09-06 15:34:58 -0700 | [diff] [blame^] | 77 | /* |
| 78 | * Everything starting with bi_max_vecs will be preserved by bio_reset() |
| 79 | */ |
| 80 | |
| 81 | unsigned int bi_max_vecs; /* max bvl_vecs we can hold */ |
| 82 | |
| 83 | atomic_t bi_cnt; /* pin count */ |
| 84 | |
| 85 | struct bio_vec *bi_io_vec; /* the actual vec list */ |
| 86 | |
Kent Overstreet | 395c72a | 2012-09-06 15:34:55 -0700 | [diff] [blame] | 87 | /* If bi_pool is non NULL, bi_destructor is not called */ |
| 88 | struct bio_set *bi_pool; |
| 89 | |
Tejun Heo | 7cc0158 | 2010-08-03 13:14:58 +0200 | [diff] [blame] | 90 | bio_destructor_t *bi_destructor; /* destructor */ |
| 91 | |
| 92 | /* |
| 93 | * We can inline a number of vecs at the end of the bio, to avoid |
| 94 | * double allocations for a small number of bio_vecs. This member |
| 95 | * MUST obviously be kept at the very end of the bio. |
| 96 | */ |
| 97 | struct bio_vec bi_inline_vecs[0]; |
| 98 | }; |
| 99 | |
Kent Overstreet | f44b48c | 2012-09-06 15:34:58 -0700 | [diff] [blame^] | 100 | #define BIO_RESET_BYTES offsetof(struct bio, bi_max_vecs) |
| 101 | |
Tejun Heo | 7cc0158 | 2010-08-03 13:14:58 +0200 | [diff] [blame] | 102 | /* |
| 103 | * bio flags |
| 104 | */ |
| 105 | #define BIO_UPTODATE 0 /* ok after I/O completion */ |
| 106 | #define BIO_RW_BLOCK 1 /* RW_AHEAD set, and read/write would block */ |
| 107 | #define BIO_EOF 2 /* out-out-bounds error */ |
| 108 | #define BIO_SEG_VALID 3 /* bi_phys_segments valid */ |
| 109 | #define BIO_CLONED 4 /* doesn't own data */ |
| 110 | #define BIO_BOUNCED 5 /* bio is a bounce bio */ |
| 111 | #define BIO_USER_MAPPED 6 /* contains user pages */ |
| 112 | #define BIO_EOPNOTSUPP 7 /* not supported */ |
Tao Ma | 9562ad9 | 2011-10-24 16:11:30 +0200 | [diff] [blame] | 113 | #define BIO_NULL_MAPPED 8 /* contains invalid user pages */ |
| 114 | #define BIO_FS_INTEGRITY 9 /* fs owns integrity data, not block layer */ |
| 115 | #define BIO_QUIET 10 /* Make BIO Quiet */ |
| 116 | #define BIO_MAPPED_INTEGRITY 11/* integrity metadata has been remapped */ |
Kent Overstreet | f44b48c | 2012-09-06 15:34:58 -0700 | [diff] [blame^] | 117 | |
| 118 | /* |
| 119 | * Flags starting here get preserved by bio_reset() - this includes |
| 120 | * BIO_POOL_IDX() |
| 121 | */ |
| 122 | #define BIO_RESET_BITS 12 |
| 123 | |
Tejun Heo | 7cc0158 | 2010-08-03 13:14:58 +0200 | [diff] [blame] | 124 | #define bio_flagged(bio, flag) ((bio)->bi_flags & (1 << (flag))) |
| 125 | |
| 126 | /* |
| 127 | * top 4 bits of bio flags indicate the pool this bio came from |
| 128 | */ |
| 129 | #define BIO_POOL_BITS (4) |
| 130 | #define BIO_POOL_NONE ((1UL << BIO_POOL_BITS) - 1) |
| 131 | #define BIO_POOL_OFFSET (BITS_PER_LONG - BIO_POOL_BITS) |
| 132 | #define BIO_POOL_MASK (1UL << BIO_POOL_OFFSET) |
| 133 | #define BIO_POOL_IDX(bio) ((bio)->bi_flags >> BIO_POOL_OFFSET) |
| 134 | |
Jens Axboe | de75d60 | 2010-08-10 12:14:27 -0400 | [diff] [blame] | 135 | #endif /* CONFIG_BLOCK */ |
| 136 | |
Tejun Heo | 7cc0158 | 2010-08-03 13:14:58 +0200 | [diff] [blame] | 137 | /* |
| 138 | * Request flags. For use in the cmd_flags field of struct request, and in |
| 139 | * bi_rw of struct bio. Note that some flags are only valid in either one. |
| 140 | */ |
| 141 | enum rq_flag_bits { |
| 142 | /* common flags */ |
| 143 | __REQ_WRITE, /* not set, read. set, write */ |
| 144 | __REQ_FAILFAST_DEV, /* no driver retries of device errors */ |
| 145 | __REQ_FAILFAST_TRANSPORT, /* no driver retries of transport errors */ |
| 146 | __REQ_FAILFAST_DRIVER, /* no driver retries of driver errors */ |
| 147 | |
Tejun Heo | 7cc0158 | 2010-08-03 13:14:58 +0200 | [diff] [blame] | 148 | __REQ_SYNC, /* request is sync (sync write or read) */ |
| 149 | __REQ_META, /* metadata io request */ |
Christoph Hellwig | 65299a3 | 2011-08-23 14:50:29 +0200 | [diff] [blame] | 150 | __REQ_PRIO, /* boost priority in cfq */ |
Tejun Heo | 7cc0158 | 2010-08-03 13:14:58 +0200 | [diff] [blame] | 151 | __REQ_DISCARD, /* request to discard sectors */ |
Matthew Wilcox | 8e4bf84 | 2011-08-11 10:36:03 +0200 | [diff] [blame] | 152 | __REQ_SECURE, /* secure discard (used with __REQ_DISCARD) */ |
| 153 | |
Tejun Heo | 7cc0158 | 2010-08-03 13:14:58 +0200 | [diff] [blame] | 154 | __REQ_NOIDLE, /* don't anticipate more IO after this one */ |
Matthew Wilcox | 8e4bf84 | 2011-08-11 10:36:03 +0200 | [diff] [blame] | 155 | __REQ_FUA, /* forced unit access */ |
| 156 | __REQ_FLUSH, /* request for cache flush */ |
Tejun Heo | 7cc0158 | 2010-08-03 13:14:58 +0200 | [diff] [blame] | 157 | |
| 158 | /* bio only flags */ |
Tejun Heo | 7cc0158 | 2010-08-03 13:14:58 +0200 | [diff] [blame] | 159 | __REQ_RAHEAD, /* read ahead, can fail anytime */ |
Vivek Goyal | e43473b | 2010-09-15 17:06:35 -0400 | [diff] [blame] | 160 | __REQ_THROTTLED, /* This bio has already been subjected to |
| 161 | * throttling rules. Don't do it again. */ |
Tejun Heo | 7cc0158 | 2010-08-03 13:14:58 +0200 | [diff] [blame] | 162 | |
| 163 | /* request only flags */ |
| 164 | __REQ_SORTED, /* elevator knows about this request */ |
| 165 | __REQ_SOFTBARRIER, /* may not be passed by ioscheduler */ |
Tejun Heo | 7cc0158 | 2010-08-03 13:14:58 +0200 | [diff] [blame] | 166 | __REQ_NOMERGE, /* don't touch this for merging */ |
| 167 | __REQ_STARTED, /* drive already may have started this one */ |
| 168 | __REQ_DONTPREP, /* don't call prep for this one */ |
| 169 | __REQ_QUEUED, /* uses queueing */ |
| 170 | __REQ_ELVPRIV, /* elevator private data attached */ |
| 171 | __REQ_FAILED, /* set if the request failed */ |
| 172 | __REQ_QUIET, /* don't worry about errors */ |
| 173 | __REQ_PREEMPT, /* set for "ide_preempt" requests */ |
Tejun Heo | 7cc0158 | 2010-08-03 13:14:58 +0200 | [diff] [blame] | 174 | __REQ_ALLOCED, /* request came from our alloc pool */ |
| 175 | __REQ_COPY_USER, /* contains copies of user pages */ |
Tejun Heo | 414b4ff | 2011-01-25 12:43:49 +0100 | [diff] [blame] | 176 | __REQ_FLUSH_SEQ, /* request for flush sequence */ |
Tejun Heo | 7cc0158 | 2010-08-03 13:14:58 +0200 | [diff] [blame] | 177 | __REQ_IO_STAT, /* account I/O stat */ |
| 178 | __REQ_MIXED_MERGE, /* merge of different types, fail separately */ |
Mel Gorman | 18022c5 | 2012-07-31 16:44:51 -0700 | [diff] [blame] | 179 | __REQ_KERNEL, /* direct IO to kernel pages */ |
Tejun Heo | 7cc0158 | 2010-08-03 13:14:58 +0200 | [diff] [blame] | 180 | __REQ_NR_BITS, /* stops here */ |
| 181 | }; |
| 182 | |
| 183 | #define REQ_WRITE (1 << __REQ_WRITE) |
| 184 | #define REQ_FAILFAST_DEV (1 << __REQ_FAILFAST_DEV) |
| 185 | #define REQ_FAILFAST_TRANSPORT (1 << __REQ_FAILFAST_TRANSPORT) |
| 186 | #define REQ_FAILFAST_DRIVER (1 << __REQ_FAILFAST_DRIVER) |
Tejun Heo | 7cc0158 | 2010-08-03 13:14:58 +0200 | [diff] [blame] | 187 | #define REQ_SYNC (1 << __REQ_SYNC) |
| 188 | #define REQ_META (1 << __REQ_META) |
Christoph Hellwig | 65299a3 | 2011-08-23 14:50:29 +0200 | [diff] [blame] | 189 | #define REQ_PRIO (1 << __REQ_PRIO) |
Tejun Heo | 7cc0158 | 2010-08-03 13:14:58 +0200 | [diff] [blame] | 190 | #define REQ_DISCARD (1 << __REQ_DISCARD) |
| 191 | #define REQ_NOIDLE (1 << __REQ_NOIDLE) |
| 192 | |
| 193 | #define REQ_FAILFAST_MASK \ |
| 194 | (REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT | REQ_FAILFAST_DRIVER) |
| 195 | #define REQ_COMMON_MASK \ |
Christoph Hellwig | 65299a3 | 2011-08-23 14:50:29 +0200 | [diff] [blame] | 196 | (REQ_WRITE | REQ_FAILFAST_MASK | REQ_SYNC | REQ_META | REQ_PRIO | \ |
| 197 | REQ_DISCARD | REQ_NOIDLE | REQ_FLUSH | REQ_FUA | REQ_SECURE) |
Tejun Heo | 3a2edd0 | 2010-09-03 11:56:18 +0200 | [diff] [blame] | 198 | #define REQ_CLONE_MASK REQ_COMMON_MASK |
Tejun Heo | 7cc0158 | 2010-08-03 13:14:58 +0200 | [diff] [blame] | 199 | |
Tejun Heo | 7cc0158 | 2010-08-03 13:14:58 +0200 | [diff] [blame] | 200 | #define REQ_RAHEAD (1 << __REQ_RAHEAD) |
Vivek Goyal | e43473b | 2010-09-15 17:06:35 -0400 | [diff] [blame] | 201 | #define REQ_THROTTLED (1 << __REQ_THROTTLED) |
Tejun Heo | 7cc0158 | 2010-08-03 13:14:58 +0200 | [diff] [blame] | 202 | |
| 203 | #define REQ_SORTED (1 << __REQ_SORTED) |
| 204 | #define REQ_SOFTBARRIER (1 << __REQ_SOFTBARRIER) |
| 205 | #define REQ_FUA (1 << __REQ_FUA) |
| 206 | #define REQ_NOMERGE (1 << __REQ_NOMERGE) |
| 207 | #define REQ_STARTED (1 << __REQ_STARTED) |
| 208 | #define REQ_DONTPREP (1 << __REQ_DONTPREP) |
| 209 | #define REQ_QUEUED (1 << __REQ_QUEUED) |
| 210 | #define REQ_ELVPRIV (1 << __REQ_ELVPRIV) |
| 211 | #define REQ_FAILED (1 << __REQ_FAILED) |
| 212 | #define REQ_QUIET (1 << __REQ_QUIET) |
| 213 | #define REQ_PREEMPT (1 << __REQ_PREEMPT) |
Tejun Heo | 7cc0158 | 2010-08-03 13:14:58 +0200 | [diff] [blame] | 214 | #define REQ_ALLOCED (1 << __REQ_ALLOCED) |
| 215 | #define REQ_COPY_USER (1 << __REQ_COPY_USER) |
Tejun Heo | 7cc0158 | 2010-08-03 13:14:58 +0200 | [diff] [blame] | 216 | #define REQ_FLUSH (1 << __REQ_FLUSH) |
Tejun Heo | 414b4ff | 2011-01-25 12:43:49 +0100 | [diff] [blame] | 217 | #define REQ_FLUSH_SEQ (1 << __REQ_FLUSH_SEQ) |
Tejun Heo | 7cc0158 | 2010-08-03 13:14:58 +0200 | [diff] [blame] | 218 | #define REQ_IO_STAT (1 << __REQ_IO_STAT) |
| 219 | #define REQ_MIXED_MERGE (1 << __REQ_MIXED_MERGE) |
Adrian Hunter | 8d57a98 | 2010-08-11 14:17:49 -0700 | [diff] [blame] | 220 | #define REQ_SECURE (1 << __REQ_SECURE) |
Mel Gorman | 18022c5 | 2012-07-31 16:44:51 -0700 | [diff] [blame] | 221 | #define REQ_KERNEL (1 << __REQ_KERNEL) |
Tejun Heo | 7cc0158 | 2010-08-03 13:14:58 +0200 | [diff] [blame] | 222 | |
Tejun Heo | 7cc0158 | 2010-08-03 13:14:58 +0200 | [diff] [blame] | 223 | #endif /* __LINUX_BLK_TYPES_H */ |