[linux-block.git] / include / linux / blk_types.h

/* SPDX-License-Identifier: GPL-2.0 */
/*
 * 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.
 * Alpha cannot write a byte atomically, so we need to use 32-bit value.
 */
#if defined(CONFIG_ALPHA) && !defined(__alpha_bwx__)
typedef u32 __bitwise blk_status_t;
#else
typedef u8 __bitwise blk_status_t;
#endif
#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)

/*
 * BLK_STS_DEV_RESOURCE is returned from the driver to the block layer if
 * device related resources are unavailable, but the driver can guarantee
 * that the queue will be rerun in the future once resources become
 * available again. This is typically the case for device specific
 * resources that are consumed for IO. If the driver fails allocating these
 * resources, we know that inflight (or pending) IO will free these
 * resource upon completion.
 *
 * This is different from BLK_STS_RESOURCE in that it explicitly references
 * a device specific resource. For resources of wider scope, allocation
 * failure can happen without having pending IO. This means that we can't
 * rely on request completions freeing these resources, as IO may not be in
 * flight. Examples of that are kernel memory allocations, DMA mappings, or
 * any other system wide resources.
 */
#define BLK_STS_DEV_RESOURCE	((__force blk_status_t)13)

/**
 * blk_path_error - returns true if error may be path related
 * @error: status the request was completed with
 *
 * Description:
 *     This classifies block error status into non-retryable errors and ones
 *     that may be successful if retried on a failover path.
 *
 * Return:
 *     %false - retrying failover path will not help
 *     %true  - may succeed if retried
 */
static inline bool blk_path_error(blk_status_t error)
{
	switch (error) {
	case BLK_STS_NOTSUPP:
	case BLK_STS_NOSPC:
	case BLK_STS_TARGET:
	case BLK_STS_NEXUS:
	case BLK_STS_MEDIUM:
	case BLK_STS_PROTECTION:
		return false;
	}

	/* Anything else could be a path failure, so should be retried */
	return true;
}

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 gendisk		*bi_disk;
	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;
	blk_status_t		bi_status;
	u8			bi_partno;

	/* 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;

	struct bvec_iter	bi_iter;

	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

typedef __u32 __bitwise blk_mq_req_flags_t;

/*
 * 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 */
	__REQ_NOWAIT,           /* Don't wait if request will block */

	/* command specific flags for REQ_OP_WRITE_ZEROES: */
	__REQ_NOUNMAP,		/* do not free blocks when zeroing */

	/* for driver use */
	__REQ_DRV,

	__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_NOWAIT		(1ULL << __REQ_NOWAIT)

#define REQ_NOUNMAP		(1ULL << __REQ_NOUNMAP)

#define REQ_DRV			(1ULL << __REQ_DRV)

#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 {
	u64 mean;
	u64 min;
	u64 max;
	u32 nr_samples;
	u64 batch;
};

#endif /* __LINUX_BLK_TYPES_H */
Commit	Line	Data
b2441318	1	/* SPDX-License-Identifier: GPL-2.0 */
7cc01581 TH	2	/*
	3	* Block data types and constants. Directly include this file only to
	4	* break include dependency loop.
	5	*/
	6	#ifndef __LINUX_BLK_TYPES_H
	7	#define __LINUX_BLK_TYPES_H
	8
7cc01581	9	#include <linux/types.h>
0781e79e	10	#include <linux/bvec.h>
7cc01581 TH	11
	12	struct bio_set;
	13	struct bio;
	14	struct bio_integrity_payload;
	15	struct page;
	16	struct block_device;
852c788f TH	17	struct io_context;
852c788f TH	18	struct cgroup_subsys_state;
4246a0b6	19	typedef void (bio_end_io_t) (struct bio *);
7cc01581	20
2a842aca CH	21	/*
2a842aca CH	22	* Block error status values. See block/blk-core:blk_errors for the details.
6e2fb221	23	* Alpha cannot write a byte atomically, so we need to use 32-bit value.
2a842aca	24	*/
6e2fb221 MP	25	#if defined(CONFIG_ALPHA) && !defined(__alpha_bwx__)
	26	typedef u32 __bitwise blk_status_t;
	27	#else
2a842aca	28	typedef u8 __bitwise blk_status_t;
6e2fb221	29	#endif
2a842aca CH	30	#define BLK_STS_OK 0
	31	#define BLK_STS_NOTSUPP ((__force blk_status_t)1)
	32	#define BLK_STS_TIMEOUT ((__force blk_status_t)2)
	33	#define BLK_STS_NOSPC ((__force blk_status_t)3)
	34	#define BLK_STS_TRANSPORT ((__force blk_status_t)4)
	35	#define BLK_STS_TARGET ((__force blk_status_t)5)
	36	#define BLK_STS_NEXUS ((__force blk_status_t)6)
	37	#define BLK_STS_MEDIUM ((__force blk_status_t)7)
	38	#define BLK_STS_PROTECTION ((__force blk_status_t)8)
	39	#define BLK_STS_RESOURCE ((__force blk_status_t)9)
	40	#define BLK_STS_IOERR ((__force blk_status_t)10)
	41
4e4cbee9 CH	42	/* hack for device mapper, don't use elsewhere: */
	43	#define BLK_STS_DM_REQUEUE ((__force blk_status_t)11)
	44
03a07c92 GR	45	#define BLK_STS_AGAIN ((__force blk_status_t)12)
03a07c92 GR	46
86ff7c2a ML	47	/*
	48	* BLK_STS_DEV_RESOURCE is returned from the driver to the block layer if
	49	* device related resources are unavailable, but the driver can guarantee
	50	* that the queue will be rerun in the future once resources become
	51	* available again. This is typically the case for device specific
	52	* resources that are consumed for IO. If the driver fails allocating these
	53	* resources, we know that inflight (or pending) IO will free these
	54	* resource upon completion.
	55	*
	56	* This is different from BLK_STS_RESOURCE in that it explicitly references
	57	* a device specific resource. For resources of wider scope, allocation
	58	* failure can happen without having pending IO. This means that we can't
	59	* rely on request completions freeing these resources, as IO may not be in
	60	* flight. Examples of that are kernel memory allocations, DMA mappings, or
	61	* any other system wide resources.
	62	*/
	63	#define BLK_STS_DEV_RESOURCE ((__force blk_status_t)13)
	64
9111e568 KB	65	/**
	66	* blk_path_error - returns true if error may be path related
	67	* @error: status the request was completed with
	68	*
	69	* Description:
	70	* This classifies block error status into non-retryable errors and ones
	71	* that may be successful if retried on a failover path.
	72	*
	73	* Return:
	74	* %false - retrying failover path will not help
	75	* %true - may succeed if retried
	76	*/
	77	static inline bool blk_path_error(blk_status_t error)
	78	{
	79	switch (error) {
	80	case BLK_STS_NOTSUPP:
	81	case BLK_STS_NOSPC:
	82	case BLK_STS_TARGET:
	83	case BLK_STS_NEXUS:
	84	case BLK_STS_MEDIUM:
	85	case BLK_STS_PROTECTION:
	86	return false;
	87	}
	88
	89	/* Anything else could be a path failure, so should be retried */
	90	return true;
	91	}
	92
b9147dd1 SL	93	struct blk_issue_stat {
	94	u64 stat;
	95	};
	96
7cc01581 TH	97	/*
	98	* main unit of I/O for the block layer and lower layers (ie drivers and
	99	* stacking drivers)
	100	*/
	101	struct bio {
7cc01581	102	struct bio bi_next; / request queue link */
74d46992	103	struct gendisk *bi_disk;
1eff9d32 JA	104	unsigned int bi_opf; /* bottom bits req flags,
	105	* top bits REQ_OP. Use
	106	* accessors.
4e1b2d52	107	*/
dbde775c	108	unsigned short bi_flags; /* status, etc and bvec pool number */
43b62ce3	109	unsigned short bi_ioprio;
cb6934f8	110	unsigned short bi_write_hint;
111be883 SL	111	blk_status_t bi_status;
111be883 SL	112	u8 bi_partno;
7cc01581 TH	113
	114	/* Number of segments in this BIO after
	115	* physical address coalescing is performed.
	116	*/
	117	unsigned int bi_phys_segments;
	118
7cc01581 TH	119	/*
	120	* To keep track of the max segment size, we account for the
	121	* sizes of the first and last mergeable segments in this bio.
	122	*/
	123	unsigned int bi_seg_front_size;
	124	unsigned int bi_seg_back_size;
	125
111be883	126	struct bvec_iter bi_iter;
196d38bc	127
111be883	128	atomic_t __bi_remaining;
7cc01581 TH	129	bio_end_io_t *bi_end_io;
	130
	131	void *bi_private;
852c788f TH	132	#ifdef CONFIG_BLK_CGROUP
	133	/*
	134	* Optional ioc and css associated with this bio. Put on bio
	135	* release. Read comment on top of bio_associate_current().
	136	*/
	137	struct io_context *bi_ioc;
	138	struct cgroup_subsys_state *bi_css;
9e234eea SL	139	#ifdef CONFIG_BLK_DEV_THROTTLING_LOW
9e234eea SL	140	void *bi_cg_private;
b9147dd1	141	struct blk_issue_stat bi_issue_stat;
9e234eea	142	#endif
852c788f	143	#endif
180b2f95	144	union {
7cc01581	145	#if defined(CONFIG_BLK_DEV_INTEGRITY)
180b2f95	146	struct bio_integrity_payload bi_integrity; / data integrity */
7cc01581	147	#endif
180b2f95	148	};
7cc01581	149
4f024f37 KO	150	unsigned short bi_vcnt; /* how many bio_vec's */
4f024f37 KO	151
f44b48c7 KO	152	/*
	153	* Everything starting with bi_max_vecs will be preserved by bio_reset()
	154	*/
	155
4f024f37	156	unsigned short bi_max_vecs; /* max bvl_vecs we can hold */
f44b48c7	157
dac56212	158	atomic_t __bi_cnt; /* pin count */
f44b48c7 KO	159
	160	struct bio_vec bi_io_vec; / the actual vec list */
	161
395c72a7 KO	162	struct bio_set *bi_pool;
395c72a7 KO	163
7cc01581 TH	164	/*
	165	* We can inline a number of vecs at the end of the bio, to avoid
	166	* double allocations for a small number of bio_vecs. This member
	167	* MUST obviously be kept at the very end of the bio.
	168	*/
	169	struct bio_vec bi_inline_vecs[0];
	170	};
	171
f44b48c7 KO	172	#define BIO_RESET_BYTES offsetof(struct bio, bi_max_vecs)
f44b48c7 KO	173
7cc01581 TH	174	/*
	175	* bio flags
	176	*/
b2dbe0a6 JA	177	#define BIO_SEG_VALID 1 /* bi_phys_segments valid */
	178	#define BIO_CLONED 2 /* doesn't own data */
	179	#define BIO_BOUNCED 3 /* bio is a bounce bio */
	180	#define BIO_USER_MAPPED 4 /* contains user pages */
	181	#define BIO_NULL_MAPPED 5 /* contains invalid user pages */
	182	#define BIO_QUIET 6 /* Make BIO Quiet */
a3ad0a9d JK	183	#define BIO_CHAIN 7 /* chained bio, ->bi_remaining in effect */
a3ad0a9d JK	184	#define BIO_REFFED 8 /* bio has elevated ->bi_cnt */
8d2bbd4c CH	185	#define BIO_THROTTLED 9 /* This bio has already been subjected to
8d2bbd4c CH	186	* throttling rules. Don't do it again. */
fbbaf700 N	187	#define BIO_TRACE_COMPLETION 10 /* bio_endio() should trace the final completion
fbbaf700 N	188	* of this bio. */
dbde775c	189	/* See BVEC_POOL_OFFSET below before adding new flags */
f44b48c7	190
7cc01581	191	/*
ed996a52 CH	192	* We support 6 different bvec pools, the last one is magic in that it
ed996a52 CH	193	* is backed by a mempool.
7cc01581	194	*/
ed996a52 CH	195	#define BVEC_POOL_NR 6
	196	#define BVEC_POOL_MAX (BVEC_POOL_NR - 1)
	197
	198	/*
dbde775c	199	* Top 3 bits of bio flags indicate the pool the bvecs came from. We add
ed996a52 CH	200	* 1 to the actual index so that 0 indicates that there are no bvecs to be
	201	* freed.
	202	*/
dbde775c	203	#define BVEC_POOL_BITS (3)
c0acf12a	204	#define BVEC_POOL_OFFSET (16 - BVEC_POOL_BITS)
ed996a52	205	#define BVEC_POOL_IDX(bio) ((bio)->bi_flags >> BVEC_POOL_OFFSET)
dbde775c N	206	#if (1<< BVEC_POOL_BITS) < (BVEC_POOL_NR+1)
	207	# error "BVEC_POOL_BITS is too small"
	208	#endif
	209
	210	/*
	211	* Flags starting here get preserved by bio_reset() - this includes
	212	* only BVEC_POOL_IDX()
	213	*/
	214	#define BIO_RESET_BITS BVEC_POOL_OFFSET
7cc01581	215
9a95e4ef BVA	216	typedef __u32 __bitwise blk_mq_req_flags_t;
9a95e4ef BVA	217
7cc01581	218	/*
ef295ecf CH	219	* Operations and flags common to the bio and request structures.
ef295ecf CH	220	* We use 8 bits for encoding the operation, and the remaining 24 for flags.
87374179 CH	221	*
	222	* The least significant bit of the operation number indicates the data
	223	* transfer direction:
	224	*
	225	* - if the least significant bit is set transfers are TO the device
	226	* - if the least significant bit is not set transfers are FROM the device
	227	*
	228	* If a operation does not transfer data the least significant bit has no
	229	* meaning.
7cc01581	230	*/
ef295ecf CH	231	#define REQ_OP_BITS 8
	232	#define REQ_OP_MASK ((1 << REQ_OP_BITS) - 1)
	233	#define REQ_FLAG_BITS 24
	234
	235	enum req_opf {
87374179 CH	236	/* read sectors from the device */
	237	REQ_OP_READ = 0,
	238	/* write sectors to the device */
	239	REQ_OP_WRITE = 1,
	240	/* flush the volatile write cache */
	241	REQ_OP_FLUSH = 2,
	242	/* discard sectors */
	243	REQ_OP_DISCARD = 3,
	244	/* get zone information */
	245	REQ_OP_ZONE_REPORT = 4,
	246	/* securely erase sectors */
	247	REQ_OP_SECURE_ERASE = 5,
	248	/* seset a zone write pointer */
	249	REQ_OP_ZONE_RESET = 6,
	250	/* write the same sector many times */
	251	REQ_OP_WRITE_SAME = 7,
a6f0788e	252	/* write the zero filled sector many times */
1d62ac13	253	REQ_OP_WRITE_ZEROES = 9,
ef295ecf	254
aebf526b CH	255	/* SCSI passthrough using struct scsi_request */
	256	REQ_OP_SCSI_IN = 32,
	257	REQ_OP_SCSI_OUT = 33,
	258	/* Driver private requests */
	259	REQ_OP_DRV_IN = 34,
	260	REQ_OP_DRV_OUT = 35,
	261
ef295ecf CH	262	REQ_OP_LAST,
	263	};
	264
	265	enum req_flag_bits {
	266	__REQ_FAILFAST_DEV = /* no driver retries of device errors */
	267	REQ_OP_BITS,
7cc01581 TH	268	__REQ_FAILFAST_TRANSPORT, /* no driver retries of transport errors */
7cc01581 TH	269	__REQ_FAILFAST_DRIVER, /* no driver retries of driver errors */
7cc01581 TH	270	__REQ_SYNC, /* request is sync (sync write or read) */
7cc01581 TH	271	__REQ_META, /* metadata io request */
65299a3b	272	__REQ_PRIO, /* boost priority in cfq */
bd1c1c21	273	__REQ_NOMERGE, /* don't touch this for merging */
a2b80967	274	__REQ_IDLE, /* anticipate more IO after this one */
180b2f95	275	__REQ_INTEGRITY, /* I/O includes block integrity payload */
8e4bf844	276	__REQ_FUA, /* forced unit access */
28a8f0d3	277	__REQ_PREFLUSH, /* request for cache flush */
188bd2b1	278	__REQ_RAHEAD, /* read ahead, can fail anytime */
1d796d6a	279	__REQ_BACKGROUND, /* background IO */
8977f563	280	__REQ_NOWAIT, /* Don't wait if request will block */
d928be9f CH	281
	282	/* command specific flags for REQ_OP_WRITE_ZEROES: */
	283	__REQ_NOUNMAP, /* do not free blocks when zeroing */
	284
96222bcc CH	285	/* for driver use */
	286	__REQ_DRV,
	287
7cc01581 TH	288	__REQ_NR_BITS, /* stops here */
	289	};
	290
5953316d JA	291	#define REQ_FAILFAST_DEV (1ULL << __REQ_FAILFAST_DEV)
	292	#define REQ_FAILFAST_TRANSPORT (1ULL << __REQ_FAILFAST_TRANSPORT)
	293	#define REQ_FAILFAST_DRIVER (1ULL << __REQ_FAILFAST_DRIVER)
	294	#define REQ_SYNC (1ULL << __REQ_SYNC)
	295	#define REQ_META (1ULL << __REQ_META)
	296	#define REQ_PRIO (1ULL << __REQ_PRIO)
ef295ecf	297	#define REQ_NOMERGE (1ULL << __REQ_NOMERGE)
a2b80967	298	#define REQ_IDLE (1ULL << __REQ_IDLE)
180b2f95	299	#define REQ_INTEGRITY (1ULL << __REQ_INTEGRITY)
ef295ecf CH	300	#define REQ_FUA (1ULL << __REQ_FUA)
	301	#define REQ_PREFLUSH (1ULL << __REQ_PREFLUSH)
	302	#define REQ_RAHEAD (1ULL << __REQ_RAHEAD)
1d796d6a	303	#define REQ_BACKGROUND (1ULL << __REQ_BACKGROUND)
8977f563	304	#define REQ_NOWAIT (1ULL << __REQ_NOWAIT)
7cc01581	305
d928be9f CH	306	#define REQ_NOUNMAP (1ULL << __REQ_NOUNMAP)
d928be9f CH	307
96222bcc	308	#define REQ_DRV (1ULL << __REQ_DRV)
d928be9f	309
7cc01581 TH	310	#define REQ_FAILFAST_MASK \
7cc01581 TH	311	(REQ_FAILFAST_DEV \| REQ_FAILFAST_TRANSPORT \| REQ_FAILFAST_DRIVER)
7cc01581	312
e2a60da7	313	#define REQ_NOMERGE_FLAGS \
e8064021	314	(REQ_NOMERGE \| REQ_PREFLUSH \| REQ_FUA)
e2a60da7	315
ef295ecf CH	316	#define bio_op(bio) \
	317	((bio)->bi_opf & REQ_OP_MASK)
	318	#define req_op(req) \
	319	((req)->cmd_flags & REQ_OP_MASK)
7cc01581	320
ef295ecf	321	/* obsolete, don't use in new code */
93c5bdf7 CH	322	static inline void bio_set_op_attrs(struct bio *bio, unsigned op,
	323	unsigned op_flags)
	324	{
	325	bio->bi_opf = op \| op_flags;
	326	}
c11f0c0b	327
87374179 CH	328	static inline bool op_is_write(unsigned int op)
	329	{
	330	return (op & 1);
	331	}
	332
f73f44eb CH	333	/*
	334	* Check if the bio or request is one that needs special treatment in the
	335	* flush state machine.
	336	*/
	337	static inline bool op_is_flush(unsigned int op)
	338	{
	339	return op & (REQ_FUA \| REQ_PREFLUSH);
	340	}
	341
b685d3d6 CH	342	/*
	343	* Reads are always treated as synchronous, as are requests with the FUA or
	344	* PREFLUSH flag. Other operations may be marked as synchronous using the
	345	* REQ_SYNC flag.
	346	*/
ef295ecf CH	347	static inline bool op_is_sync(unsigned int op)
ef295ecf CH	348	{
b685d3d6 CH	349	return (op & REQ_OP_MASK) == REQ_OP_READ \|\|
b685d3d6 CH	350	(op & (REQ_SYNC \| REQ_FUA \| REQ_PREFLUSH));
ef295ecf	351	}
c11f0c0b	352
dece1635	353	typedef unsigned int blk_qc_t;
fd2d3326 JA	354	#define BLK_QC_T_NONE -1U
	355	#define BLK_QC_T_SHIFT 16
	356	#define BLK_QC_T_INTERNAL (1U << 31)
dece1635 JA	357
	358	static inline bool blk_qc_t_valid(blk_qc_t cookie)
	359	{
	360	return cookie != BLK_QC_T_NONE;
	361	}
	362
fd2d3326 JA	363	static inline blk_qc_t blk_tag_to_qc_t(unsigned int tag, unsigned int queue_num,
fd2d3326 JA	364	bool internal)
dece1635	365	{
fd2d3326 JA	366	blk_qc_t ret = tag \| (queue_num << BLK_QC_T_SHIFT);
	367
	368	if (internal)
	369	ret \|= BLK_QC_T_INTERNAL;
	370
	371	return ret;
dece1635 JA	372	}
	373
	374	static inline unsigned int blk_qc_t_to_queue_num(blk_qc_t cookie)
	375	{
fd2d3326	376	return (cookie & ~BLK_QC_T_INTERNAL) >> BLK_QC_T_SHIFT;
dece1635 JA	377	}
	378
	379	static inline unsigned int blk_qc_t_to_tag(blk_qc_t cookie)
	380	{
e3a7a3bf	381	return cookie & ((1u << BLK_QC_T_SHIFT) - 1);
dece1635 JA	382	}
dece1635 JA	383
fd2d3326 JA	384	static inline bool blk_qc_t_is_internal(blk_qc_t cookie)
	385	{
	386	return (cookie & BLK_QC_T_INTERNAL) != 0;
	387	}
	388
cf43e6be	389	struct blk_rq_stat {
eca8b53a	390	u64 mean;
cf43e6be JA	391	u64 min;
cf43e6be JA	392	u64 max;
eca8b53a	393	u32 nr_samples;
cf43e6be	394	u64 batch;
cf43e6be JA	395	};
cf43e6be JA	396
7cc01581	397	#endif /* __LINUX_BLK_TYPES_H */