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 12struct bio_set; 13struct bio; 14struct bio_integrity_payload; 15struct page; 16struct block_device; 17typedef void (bio_end_io_t) (struct bio *, int); 18typedef 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 */ 23struct 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 */ 33struct 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 */ 100#define bio_flagged(bio, flag) ((bio)->bi_flags & (1 << (flag))) 101 102/* 103 * top 4 bits of bio flags indicate the pool this bio came from 104 */ 105#define BIO_POOL_BITS (4) 106#define BIO_POOL_NONE ((1UL << BIO_POOL_BITS) - 1) 107#define BIO_POOL_OFFSET (BITS_PER_LONG - BIO_POOL_BITS) 108#define BIO_POOL_MASK (1UL << BIO_POOL_OFFSET) 109#define BIO_POOL_IDX(bio) ((bio)->bi_flags >> BIO_POOL_OFFSET) 110 111#endif /* CONFIG_BLOCK */ 112 113/* 114 * Request flags. For use in the cmd_flags field of struct request, and in 115 * bi_rw of struct bio. Note that some flags are only valid in either one. 116 */ 117enum rq_flag_bits { 118 /* common flags */ 119 __REQ_WRITE, /* not set, read. set, write */ 120 __REQ_FAILFAST_DEV, /* no driver retries of device errors */ 121 __REQ_FAILFAST_TRANSPORT, /* no driver retries of transport errors */ 122 __REQ_FAILFAST_DRIVER, /* no driver retries of driver errors */ 123 124 __REQ_HARDBARRIER, /* may not be passed by drive either */ 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 */ 133 134 /* request only flags */ 135 __REQ_SORTED, /* elevator knows about this request */ 136 __REQ_SOFTBARRIER, /* may not be passed by ioscheduler */ 137 __REQ_FUA, /* forced unit access */ 138 __REQ_NOMERGE, /* don't touch this for merging */ 139 __REQ_STARTED, /* drive already may have started this one */ 140 __REQ_DONTPREP, /* don't call prep for this one */ 141 __REQ_QUEUED, /* uses queueing */ 142 __REQ_ELVPRIV, /* elevator private data attached */ 143 __REQ_FAILED, /* set if the request failed */ 144 __REQ_QUIET, /* don't worry about errors */ 145 __REQ_PREEMPT, /* set for "ide_preempt" requests */ 146 __REQ_ORDERED_COLOR, /* is before or after barrier */ 147 __REQ_ALLOCED, /* request came from our alloc pool */ 148 __REQ_COPY_USER, /* contains copies of user pages */ 149 __REQ_INTEGRITY, /* integrity metadata has been remapped */ 150 __REQ_FLUSH, /* request for cache flush */ 151 __REQ_IO_STAT, /* account I/O stat */ 152 __REQ_MIXED_MERGE, /* merge of different types, fail separately */ 153 __REQ_SECURE, /* secure discard (used with __REQ_DISCARD) */ 154 __REQ_NR_BITS, /* stops here */ 155}; 156 157#define REQ_WRITE (1 << __REQ_WRITE) 158#define REQ_FAILFAST_DEV (1 << __REQ_FAILFAST_DEV) 159#define REQ_FAILFAST_TRANSPORT (1 << __REQ_FAILFAST_TRANSPORT) 160#define REQ_FAILFAST_DRIVER (1 << __REQ_FAILFAST_DRIVER) 161#define REQ_HARDBARRIER (1 << __REQ_HARDBARRIER) 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 \ 170 (REQ_WRITE | REQ_FAILFAST_MASK | REQ_HARDBARRIER | REQ_SYNC | \ 171 REQ_META| REQ_DISCARD | REQ_NOIDLE) 172 173#define REQ_UNPLUG (1 << __REQ_UNPLUG) 174#define REQ_RAHEAD (1 << __REQ_RAHEAD) 175 176#define REQ_SORTED (1 << __REQ_SORTED) 177#define REQ_SOFTBARRIER (1 << __REQ_SOFTBARRIER) 178#define REQ_FUA (1 << __REQ_FUA) 179#define REQ_NOMERGE (1 << __REQ_NOMERGE) 180#define REQ_STARTED (1 << __REQ_STARTED) 181#define REQ_DONTPREP (1 << __REQ_DONTPREP) 182#define REQ_QUEUED (1 << __REQ_QUEUED) 183#define REQ_ELVPRIV (1 << __REQ_ELVPRIV) 184#define REQ_FAILED (1 << __REQ_FAILED) 185#define REQ_QUIET (1 << __REQ_QUIET) 186#define REQ_PREEMPT (1 << __REQ_PREEMPT) 187#define REQ_ORDERED_COLOR (1 << __REQ_ORDERED_COLOR) 188#define REQ_ALLOCED (1 << __REQ_ALLOCED) 189#define REQ_COPY_USER (1 << __REQ_COPY_USER) 190#define REQ_INTEGRITY (1 << __REQ_INTEGRITY) 191#define REQ_FLUSH (1 << __REQ_FLUSH) 192#define REQ_IO_STAT (1 << __REQ_IO_STAT) 193#define REQ_MIXED_MERGE (1 << __REQ_MIXED_MERGE) 194#define REQ_SECURE (1 << __REQ_SECURE) 195 196#endif /* __LINUX_BLK_TYPES_H */ 197