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/*
* 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 *);
#ifdef CONFIG_BLOCK
/*
* 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, command, etc */
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;
#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_OP_SHIFT (8 * FIELD_SIZEOF(struct bio, bi_opf) - REQ_OP_BITS)
#define bio_flags(bio) ((bio)->bi_opf & ((1 << BIO_OP_SHIFT) - 1))
#define bio_op(bio) ((bio)->bi_opf >> BIO_OP_SHIFT)
#define bio_set_op_attrs(bio, op, op_flags) do { \
if (__builtin_constant_p(op)) \
BUILD_BUG_ON((op) + 0U >= (1U << REQ_OP_BITS)); \
else \
WARN_ON_ONCE((op) + 0U >= (1U << REQ_OP_BITS)); \
if (__builtin_constant_p(op_flags)) \
BUILD_BUG_ON((op_flags) + 0U >= (1U << BIO_OP_SHIFT)); \
else \
WARN_ON_ONCE((op_flags) + 0U >= (1U << BIO_OP_SHIFT)); \
(bio)->bi_opf = bio_flags(bio); \
(bio)->bi_opf |= (((op) + 0U) << BIO_OP_SHIFT); \
(bio)->bi_opf |= (op_flags); \
} while (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 */
/*
* Flags starting here get preserved by bio_reset() - this includes
* BVEC_POOL_IDX()
*/
#define BIO_RESET_BITS 10
/*
* 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 4 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 (4)
#define BVEC_POOL_OFFSET (16 - BVEC_POOL_BITS)
#define BVEC_POOL_IDX(bio) ((bio)->bi_flags >> BVEC_POOL_OFFSET)
#endif /* CONFIG_BLOCK */
/*
* Request flags. For use in the cmd_flags field of struct request, and in
* bi_opf of struct bio. Note that some flags are only valid in either one.
*/
enum rq_flag_bits {
/* common flags */
__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_NOMERGE, /* don't touch this for merging */
__REQ_NOIDLE, /* don't 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 */
/* bio only flags */
__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_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_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_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_FAILFAST_MASK | REQ_SYNC | REQ_META | REQ_PRIO | REQ_NOIDLE | \
REQ_PREFLUSH | REQ_FUA | REQ_INTEGRITY | REQ_NOMERGE | REQ_RAHEAD)
#define REQ_CLONE_MASK REQ_COMMON_MASK
/* This mask is used for both bio and request merge checking */
#define REQ_NOMERGE_FLAGS \
(REQ_NOMERGE | REQ_STARTED | REQ_SOFTBARRIER | REQ_PREFLUSH | REQ_FUA | REQ_FLUSH_SEQ)
#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_PREFLUSH (1ULL << __REQ_PREFLUSH)
#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_PM (1ULL << __REQ_PM)
#define REQ_HASHED (1ULL << __REQ_HASHED)
#define REQ_MQ_INFLIGHT (1ULL << __REQ_MQ_INFLIGHT)
enum req_op {
REQ_OP_READ,
REQ_OP_WRITE,
REQ_OP_DISCARD, /* request to discard sectors */
REQ_OP_SECURE_ERASE, /* request to securely erase sectors */
REQ_OP_WRITE_SAME, /* write same block many times */
REQ_OP_FLUSH, /* request for cache flush */
REQ_OP_ZONE_REPORT, /* Get zone information */
REQ_OP_ZONE_RESET, /* Reset a zone write pointer */
};
#define REQ_OP_BITS 3
typedef unsigned int blk_qc_t;
#define BLK_QC_T_NONE -1U
#define BLK_QC_T_SHIFT 16
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)
{
return tag | (queue_num << BLK_QC_T_SHIFT);
}
static inline unsigned int blk_qc_t_to_queue_num(blk_qc_t cookie)
{
return cookie >> 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);
}
#endif /* __LINUX_BLK_TYPES_H */
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