| /* |
| * 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 <linux/types.h> |
| #include <linux/bvec.h> |
| |
| 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 *); |
| |
| struct blk_issue_stat { |
| u64 stat; |
| }; |
| |
| /* |
| * 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; |
| int bi_error; |
| unsigned int bi_opf; /* bottom bits req flags, |
| * top bits REQ_OP. Use |
| * accessors. |
| */ |
| unsigned short bi_flags; /* status, etc and bvec pool number */ |
| unsigned short bi_ioprio; |
| |
| 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; |
| #ifdef CONFIG_BLK_DEV_THROTTLING_LOW |
| void *bi_cg_private; |
| struct blk_issue_stat bi_issue_stat; |
| #endif |
| #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_SEG_VALID 1 /* bi_phys_segments valid */ |
| #define BIO_CLONED 2 /* doesn't own data */ |
| #define BIO_BOUNCED 3 /* bio is a bounce bio */ |
| #define BIO_USER_MAPPED 4 /* contains user pages */ |
| #define BIO_NULL_MAPPED 5 /* contains invalid user pages */ |
| #define BIO_QUIET 6 /* Make BIO Quiet */ |
| #define BIO_CHAIN 7 /* chained bio, ->bi_remaining in effect */ |
| #define BIO_REFFED 8 /* bio has elevated ->bi_cnt */ |
| #define BIO_THROTTLED 9 /* This bio has already been subjected to |
| * throttling rules. Don't do it again. */ |
| #define BIO_TRACE_COMPLETION 10 /* bio_endio() should trace the final completion |
| * of this bio. */ |
| /* See BVEC_POOL_OFFSET below before adding new flags */ |
| |
| /* |
| * We support 6 different bvec pools, the last one is magic in that it |
| * is backed by a mempool. |
| */ |
| #define BVEC_POOL_NR 6 |
| #define BVEC_POOL_MAX (BVEC_POOL_NR - 1) |
| |
| /* |
| * Top 3 bits of bio flags indicate the pool the bvecs came from. We add |
| * 1 to the actual index so that 0 indicates that there are no bvecs to be |
| * freed. |
| */ |
| #define BVEC_POOL_BITS (3) |
| #define BVEC_POOL_OFFSET (16 - BVEC_POOL_BITS) |
| #define BVEC_POOL_IDX(bio) ((bio)->bi_flags >> BVEC_POOL_OFFSET) |
| #if (1<< BVEC_POOL_BITS) < (BVEC_POOL_NR+1) |
| # error "BVEC_POOL_BITS is too small" |
| #endif |
| |
| /* |
| * Flags starting here get preserved by bio_reset() - this includes |
| * only BVEC_POOL_IDX() |
| */ |
| #define BIO_RESET_BITS BVEC_POOL_OFFSET |
| |
| /* |
| * Operations and flags common to the bio and request structures. |
| * We use 8 bits for encoding the operation, and the remaining 24 for flags. |
| * |
| * The least significant bit of the operation number indicates the data |
| * transfer direction: |
| * |
| * - if the least significant bit is set transfers are TO the device |
| * - if the least significant bit is not set transfers are FROM the device |
| * |
| * If a operation does not transfer data the least significant bit has no |
| * meaning. |
| */ |
| #define REQ_OP_BITS 8 |
| #define REQ_OP_MASK ((1 << REQ_OP_BITS) - 1) |
| #define REQ_FLAG_BITS 24 |
| |
| enum req_opf { |
| /* read sectors from the device */ |
| REQ_OP_READ = 0, |
| /* write sectors to the device */ |
| REQ_OP_WRITE = 1, |
| /* flush the volatile write cache */ |
| REQ_OP_FLUSH = 2, |
| /* discard sectors */ |
| REQ_OP_DISCARD = 3, |
| /* get zone information */ |
| REQ_OP_ZONE_REPORT = 4, |
| /* securely erase sectors */ |
| REQ_OP_SECURE_ERASE = 5, |
| /* seset a zone write pointer */ |
| REQ_OP_ZONE_RESET = 6, |
| /* write the same sector many times */ |
| REQ_OP_WRITE_SAME = 7, |
| /* write the zero filled sector many times */ |
| REQ_OP_WRITE_ZEROES = 9, |
| |
| /* SCSI passthrough using struct scsi_request */ |
| REQ_OP_SCSI_IN = 32, |
| REQ_OP_SCSI_OUT = 33, |
| /* Driver private requests */ |
| REQ_OP_DRV_IN = 34, |
| REQ_OP_DRV_OUT = 35, |
| |
| REQ_OP_LAST, |
| }; |
| |
| enum req_flag_bits { |
| __REQ_FAILFAST_DEV = /* no driver retries of device errors */ |
| REQ_OP_BITS, |
| __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_NOMERGE, /* don't touch this for merging */ |
| __REQ_IDLE, /* anticipate more IO after this one */ |
| __REQ_INTEGRITY, /* I/O includes block integrity payload */ |
| __REQ_FUA, /* forced unit access */ |
| __REQ_PREFLUSH, /* request for cache flush */ |
| __REQ_RAHEAD, /* read ahead, can fail anytime */ |
| __REQ_BACKGROUND, /* background IO */ |
| |
| /* command specific flags for REQ_OP_WRITE_ZEROES: */ |
| __REQ_NOUNMAP, /* do not free blocks when zeroing */ |
| |
| __REQ_NR_BITS, /* stops here */ |
| }; |
| |
| #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_NOMERGE (1ULL << __REQ_NOMERGE) |
| #define REQ_IDLE (1ULL << __REQ_IDLE) |
| #define REQ_INTEGRITY (1ULL << __REQ_INTEGRITY) |
| #define REQ_FUA (1ULL << __REQ_FUA) |
| #define REQ_PREFLUSH (1ULL << __REQ_PREFLUSH) |
| #define REQ_RAHEAD (1ULL << __REQ_RAHEAD) |
| #define REQ_BACKGROUND (1ULL << __REQ_BACKGROUND) |
| |
| #define REQ_NOUNMAP (1ULL << __REQ_NOUNMAP) |
| |
| #define REQ_FAILFAST_MASK \ |
| (REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT | REQ_FAILFAST_DRIVER) |
| |
| #define REQ_NOMERGE_FLAGS \ |
| (REQ_NOMERGE | REQ_PREFLUSH | REQ_FUA) |
| |
| #define bio_op(bio) \ |
| ((bio)->bi_opf & REQ_OP_MASK) |
| #define req_op(req) \ |
| ((req)->cmd_flags & REQ_OP_MASK) |
| |
| /* obsolete, don't use in new code */ |
| static inline void bio_set_op_attrs(struct bio *bio, unsigned op, |
| unsigned op_flags) |
| { |
| bio->bi_opf = op | op_flags; |
| } |
| |
| static inline bool op_is_write(unsigned int op) |
| { |
| return (op & 1); |
| } |
| |
| /* |
| * Check if the bio or request is one that needs special treatment in the |
| * flush state machine. |
| */ |
| static inline bool op_is_flush(unsigned int op) |
| { |
| return op & (REQ_FUA | REQ_PREFLUSH); |
| } |
| |
| /* |
| * Reads are always treated as synchronous, as are requests with the FUA or |
| * PREFLUSH flag. Other operations may be marked as synchronous using the |
| * REQ_SYNC flag. |
| */ |
| static inline bool op_is_sync(unsigned int op) |
| { |
| return (op & REQ_OP_MASK) == REQ_OP_READ || |
| (op & (REQ_SYNC | REQ_FUA | REQ_PREFLUSH)); |
| } |
| |
| typedef unsigned int blk_qc_t; |
| #define BLK_QC_T_NONE -1U |
| #define BLK_QC_T_SHIFT 16 |
| #define BLK_QC_T_INTERNAL (1U << 31) |
| |
| static inline bool blk_qc_t_valid(blk_qc_t cookie) |
| { |
| return cookie != BLK_QC_T_NONE; |
| } |
| |
| static inline blk_qc_t blk_tag_to_qc_t(unsigned int tag, unsigned int queue_num, |
| bool internal) |
| { |
| blk_qc_t ret = tag | (queue_num << BLK_QC_T_SHIFT); |
| |
| if (internal) |
| ret |= BLK_QC_T_INTERNAL; |
| |
| return ret; |
| } |
| |
| static inline unsigned int blk_qc_t_to_queue_num(blk_qc_t cookie) |
| { |
| return (cookie & ~BLK_QC_T_INTERNAL) >> BLK_QC_T_SHIFT; |
| } |
| |
| static inline unsigned int blk_qc_t_to_tag(blk_qc_t cookie) |
| { |
| return cookie & ((1u << BLK_QC_T_SHIFT) - 1); |
| } |
| |
| static inline bool blk_qc_t_is_internal(blk_qc_t cookie) |
| { |
| return (cookie & BLK_QC_T_INTERNAL) != 0; |
| } |
| |
| struct blk_rq_stat { |
| s64 mean; |
| u64 min; |
| u64 max; |
| s32 nr_samples; |
| s32 nr_batch; |
| u64 batch; |
| }; |
| |
| #endif /* __LINUX_BLK_TYPES_H */ |