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Release 4.12 include/linux/blk_types.h

Directory: include/linux
/*
 * 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; }

Contributors

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Christoph Hellwig26100.00%2100.00%
Total26100.00%2100.00%


static inline bool op_is_write(unsigned int op) { return (op & 1); }

Contributors

PersonTokensPropCommitsCommitProp
Christoph Hellwig18100.00%1100.00%
Total18100.00%1100.00%

/* * 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); }

Contributors

PersonTokensPropCommitsCommitProp
Christoph Hellwig20100.00%1100.00%
Total20100.00%1100.00%

/* * 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)); }

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Christoph Hellwig2990.62%266.67%
Jens Axboe39.38%133.33%
Total32100.00%3100.00%

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; }

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Jens Axboe15100.00%1100.00%
Total15100.00%1100.00%


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; }

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Jens Axboe40100.00%2100.00%
Total40100.00%2100.00%


static inline unsigned int blk_qc_t_to_queue_num(blk_qc_t cookie) { return (cookie & ~BLK_QC_T_INTERNAL) >> BLK_QC_T_SHIFT; }

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Jens Axboe21100.00%2100.00%
Total21100.00%2100.00%


static inline unsigned int blk_qc_t_to_tag(blk_qc_t cookie) { return cookie & ((1u << BLK_QC_T_SHIFT) - 1); }

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Jens Axboe24100.00%2100.00%
Total24100.00%2100.00%


static inline bool blk_qc_t_is_internal(blk_qc_t cookie) { return (cookie & BLK_QC_T_INTERNAL) != 0; }

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Jens Axboe19100.00%1100.00%
Total19100.00%1100.00%

struct blk_rq_stat { s64 mean; u64 min; u64 max; s32 nr_samples; s32 nr_batch; u64 batch; }; #endif /* __LINUX_BLK_TYPES_H */

Overall Contributors

PersonTokensPropCommitsCommitProp
Christoph Hellwig24531.45%1430.43%
Tejun Heo21727.86%36.52%
Jens Axboe19625.16%1226.09%
Kent Overstreet344.36%48.70%
Neil Brown324.11%24.35%
Shaohua Li212.70%24.35%
Martin K. Petersen141.80%24.35%
Michael Christie60.77%36.52%
Matthew Wilcox50.64%12.17%
Chaitanya Kulkarni40.51%12.17%
Ming Lei30.39%12.17%
Jan Kara20.26%12.17%
Total779100.00%46100.00%
Directory: include/linux
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