/* * Block data types and constants. Directly include this file only to * break include dependency loop. */ #ifndef __LINUX_BLK_TYPES_H #define __LINUX_BLK_TYPES_H #include struct bio_set; struct bio; struct bio_integrity_payload; struct page; struct block_device; struct io_context; struct cgroup_subsys_state; typedef void (bio_end_io_t) (struct bio *, int); typedef void (bio_destructor_t) (struct bio *); /* * was unsigned short, but we might as well be ready for > 64kB I/O pages */ struct bio_vec { struct page *bv_page; unsigned int bv_len; unsigned int bv_offset; }; #ifdef CONFIG_BLOCK struct bvec_iter { sector_t bi_sector; /* device address in 512 byte sectors */ unsigned int bi_size; /* residual I/O count */ unsigned int bi_idx; /* current index into bvl_vec */ unsigned int bi_bvec_done; /* number of bytes completed in current bvec */ }; /* * main unit of I/O for the block layer and lower layers (ie drivers and * stacking drivers) */ struct bio { struct bio *bi_next; /* request queue link */ struct block_device *bi_bdev; unsigned long bi_flags; /* status, command, etc */ unsigned long bi_rw; /* bottom bits READ/WRITE, * top bits priority */ struct bvec_iter bi_iter; /* Number of segments in this BIO after * physical address coalescing is performed. */ unsigned int bi_phys_segments; /* * To keep track of the max segment size, we account for the * sizes of the first and last mergeable segments in this bio. */ unsigned int bi_seg_front_size; unsigned int bi_seg_back_size; atomic_t bi_remaining; bio_end_io_t *bi_end_io; void *bi_private; #ifdef CONFIG_BLK_CGROUP /* * Optional ioc and css associated with this bio. Put on bio * release. Read comment on top of bio_associate_current(). */ struct io_context *bi_ioc; struct cgroup_subsys_state *bi_css; #endif union { #if defined(CONFIG_BLK_DEV_INTEGRITY) struct bio_integrity_payload *bi_integrity; /* data integrity */ #endif }; unsigned short bi_vcnt; /* how many bio_vec's */ /* * Everything starting with bi_max_vecs will be preserved by bio_reset() */ unsigned short bi_max_vecs; /* max bvl_vecs we can hold */ atomic_t bi_cnt; /* pin count */ struct bio_vec *bi_io_vec; /* the actual vec list */ struct bio_set *bi_pool; /* * We can inline a number of vecs at the end of the bio, to avoid * double allocations for a small number of bio_vecs. This member * MUST obviously be kept at the very end of the bio. */ struct bio_vec bi_inline_vecs[0]; }; #define BIO_RESET_BYTES offsetof(struct bio, bi_max_vecs) /* * bio flags */ #define BIO_UPTODATE 0 /* ok after I/O completion */ #define BIO_RW_BLOCK 1 /* RW_AHEAD set, and read/write would block */ #define BIO_EOF 2 /* out-out-bounds error */ #define BIO_SEG_VALID 3 /* bi_phys_segments valid */ #define BIO_CLONED 4 /* doesn't own data */ #define BIO_BOUNCED 5 /* bio is a bounce bio */ #define BIO_USER_MAPPED 6 /* contains user pages */ #define BIO_EOPNOTSUPP 7 /* not supported */ #define BIO_NULL_MAPPED 8 /* contains invalid user pages */ #define BIO_QUIET 9 /* Make BIO Quiet */ #define BIO_SNAP_STABLE 10 /* bio data must be snapshotted during write */ /* * Flags starting here get preserved by bio_reset() - this includes * BIO_POOL_IDX() */ #define BIO_RESET_BITS 13 #define BIO_OWNS_VEC 13 /* bio_free() should free bvec */ #define bio_flagged(bio, flag) ((bio)->bi_flags & (1 << (flag))) /* * top 4 bits of bio flags indicate the pool this bio came from */ #define BIO_POOL_BITS (4) #define BIO_POOL_NONE ((1UL << BIO_POOL_BITS) - 1) #define BIO_POOL_OFFSET (BITS_PER_LONG - BIO_POOL_BITS) #define BIO_POOL_MASK (1UL << BIO_POOL_OFFSET) #define BIO_POOL_IDX(bio) ((bio)->bi_flags >> BIO_POOL_OFFSET) #endif /* CONFIG_BLOCK */ /* * Request flags. For use in the cmd_flags field of struct request, and in * bi_rw of struct bio. Note that some flags are only valid in either one. */ enum rq_flag_bits { /* common flags */ __REQ_WRITE, /* not set, read. set, write */ __REQ_FAILFAST_DEV, /* no driver retries of device errors */ __REQ_FAILFAST_TRANSPORT, /* no driver retries of transport errors */ __REQ_FAILFAST_DRIVER, /* no driver retries of driver errors */ __REQ_SYNC, /* request is sync (sync write or read) */ __REQ_META, /* metadata io request */ __REQ_PRIO, /* boost priority in cfq */ __REQ_DISCARD, /* request to discard sectors */ __REQ_SECURE, /* secure discard (used with __REQ_DISCARD) */ __REQ_WRITE_SAME, /* write same block many times */ __REQ_NOIDLE, /* don't anticipate more IO after this one */ __REQ_INTEGRITY, /* I/O includes block integrity payload */ __REQ_FUA, /* forced unit access */ __REQ_FLUSH, /* request for cache flush */ /* bio only flags */ __REQ_RAHEAD, /* read ahead, can fail anytime */ __REQ_THROTTLED, /* This bio has already been subjected to * throttling rules. Don't do it again. */ /* request only flags */ __REQ_SORTED, /* elevator knows about this request */ __REQ_SOFTBARRIER, /* may not be passed by ioscheduler */ __REQ_NOMERGE, /* don't touch this for merging */ __REQ_STARTED, /* drive already may have started this one */ __REQ_DONTPREP, /* don't call prep for this one */ __REQ_QUEUED, /* uses queueing */ __REQ_ELVPRIV, /* elevator private data attached */ __REQ_FAILED, /* set if the request failed */ __REQ_QUIET, /* don't worry about errors */ __REQ_PREEMPT, /* set for "ide_preempt" requests and also for requests for which the SCSI "quiesce" state must be ignored. */ __REQ_ALLOCED, /* request came from our alloc pool */ __REQ_COPY_USER, /* contains copies of user pages */ __REQ_FLUSH_SEQ, /* request for flush sequence */ __REQ_IO_STAT, /* account I/O stat */ __REQ_MIXED_MERGE, /* merge of different types, fail separately */ __REQ_PM, /* runtime pm request */ __REQ_HASHED, /* on IO scheduler merge hash */ __REQ_MQ_INFLIGHT, /* track inflight for MQ */ __REQ_NR_BITS, /* stops here */ }; #define REQ_WRITE (1ULL << __REQ_WRITE) #define REQ_FAILFAST_DEV (1ULL << __REQ_FAILFAST_DEV) #define REQ_FAILFAST_TRANSPORT (1ULL << __REQ_FAILFAST_TRANSPORT) #define REQ_FAILFAST_DRIVER (1ULL << __REQ_FAILFAST_DRIVER) #define REQ_SYNC (1ULL << __REQ_SYNC) #define REQ_META (1ULL << __REQ_META) #define REQ_PRIO (1ULL << __REQ_PRIO) #define REQ_DISCARD (1ULL << __REQ_DISCARD) #define REQ_WRITE_SAME (1ULL << __REQ_WRITE_SAME) #define REQ_NOIDLE (1ULL << __REQ_NOIDLE) #define REQ_INTEGRITY (1ULL << __REQ_INTEGRITY) #define REQ_FAILFAST_MASK \ (REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT | REQ_FAILFAST_DRIVER) #define REQ_COMMON_MASK \ (REQ_WRITE | REQ_FAILFAST_MASK | REQ_SYNC | REQ_META | REQ_PRIO | \ REQ_DISCARD | REQ_WRITE_SAME | REQ_NOIDLE | REQ_FLUSH | REQ_FUA | \ REQ_SECURE | REQ_INTEGRITY) #define REQ_CLONE_MASK REQ_COMMON_MASK #define BIO_NO_ADVANCE_ITER_MASK (REQ_DISCARD|REQ_WRITE_SAME) /* This mask is used for both bio and request merge checking */ #define REQ_NOMERGE_FLAGS \ (REQ_NOMERGE | REQ_STARTED | REQ_SOFTBARRIER | REQ_FLUSH | REQ_FUA) #define REQ_RAHEAD (1ULL << __REQ_RAHEAD) #define REQ_THROTTLED (1ULL << __REQ_THROTTLED) #define REQ_SORTED (1ULL << __REQ_SORTED) #define REQ_SOFTBARRIER (1ULL << __REQ_SOFTBARRIER) #define REQ_FUA (1ULL << __REQ_FUA) #define REQ_NOMERGE (1ULL << __REQ_NOMERGE) #define REQ_STARTED (1ULL << __REQ_STARTED) #define REQ_DONTPREP (1ULL << __REQ_DONTPREP) #define REQ_QUEUED (1ULL << __REQ_QUEUED) #define REQ_ELVPRIV (1ULL << __REQ_ELVPRIV) #define REQ_FAILED (1ULL << __REQ_FAILED) #define REQ_QUIET (1ULL << __REQ_QUIET) #define REQ_PREEMPT (1ULL << __REQ_PREEMPT) #define REQ_ALLOCED (1ULL << __REQ_ALLOCED) #define REQ_COPY_USER (1ULL << __REQ_COPY_USER) #define REQ_FLUSH (1ULL << __REQ_FLUSH) #define REQ_FLUSH_SEQ (1ULL << __REQ_FLUSH_SEQ) #define REQ_IO_STAT (1ULL << __REQ_IO_STAT) #define REQ_MIXED_MERGE (1ULL << __REQ_MIXED_MERGE) #define REQ_SECURE (1ULL << __REQ_SECURE) #define REQ_PM (1ULL << __REQ_PM) #define REQ_HASHED (1ULL << __REQ_HASHED) #define REQ_MQ_INFLIGHT (1ULL << __REQ_MQ_INFLIGHT) #endif /* __LINUX_BLK_TYPES_H */