/* * 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 *); /* * Block error status values.  See block/blk-core:blk_errors for the details. */typedef u8 __bitwise blk_status_t;#define	BLK_STS_OK 0#define BLK_STS_NOTSUPP		((__force blk_status_t)1)#define BLK_STS_TIMEOUT		((__force blk_status_t)2)#define BLK_STS_NOSPC		((__force blk_status_t)3)#define BLK_STS_TRANSPORT	((__force blk_status_t)4)#define BLK_STS_TARGET		((__force blk_status_t)5)#define BLK_STS_NEXUS		((__force blk_status_t)6)#define BLK_STS_MEDIUM		((__force blk_status_t)7)#define BLK_STS_PROTECTION	((__force blk_status_t)8)#define BLK_STS_RESOURCE	((__force blk_status_t)9)#define BLK_STS_IOERR		((__force blk_status_t)10) /* hack for device mapper, don't use elsewhere: */#define BLK_STS_DM_REQUEUE    ((__force blk_status_t)11) #define BLK_STS_AGAIN		((__force blk_status_t)12) 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;	blk_status_t		bi_status;	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;	unsigned short		bi_write_hint; 	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_NOWAIT,           /* Don't wait if request will block */	__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_NOWAIT		(1ULL << __REQ_NOWAIT) #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 */