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Diffstat (limited to 'c_src/include/linux/blk_types.h')
| -rw-r--r-- | c_src/include/linux/blk_types.h | 247 |
1 files changed, 247 insertions, 0 deletions
diff --git a/c_src/include/linux/blk_types.h b/c_src/include/linux/blk_types.h new file mode 100644 index 00000000..80560ab6 --- /dev/null +++ b/c_src/include/linux/blk_types.h @@ -0,0 +1,247 @@ +/* + * 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/atomic.h> +#include <linux/types.h> +#include <linux/bvec.h> +#include <linux/kobject.h> + +struct bio_set; +struct bio; +typedef void (bio_end_io_t) (struct bio *); + +#define BDEVNAME_SIZE 32 + +struct request_queue { + struct backing_dev_info *backing_dev_info; +}; + +struct gendisk { + struct backing_dev_info *bdi; + struct backing_dev_info __bdi; +}; + +struct hd_struct { + struct kobject kobj; +}; + +struct block_device { + struct kobject kobj; + dev_t bd_dev; + char name[BDEVNAME_SIZE]; + struct inode *bd_inode; + struct request_queue queue; + void *bd_holder; + struct gendisk * bd_disk; + struct gendisk __bd_disk; + int bd_fd; +}; + +#define bdev_kobj(_bdev) (&((_bdev)->kobj)) + +/* + * 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) + +#define BIO_INLINE_VECS 4 + +/* + * 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, command, etc */ + unsigned short bi_ioprio; + + struct bvec_iter bi_iter; + + atomic_t __bi_remaining; + + bio_end_io_t *bi_end_io; + void *bi_private; + + 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 */ + +/* + * 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) + +/* + * 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 = 8, + + /* 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_NR_BITS, /* stops here */ +}; + +#define REQ_SYNC (1ULL << __REQ_SYNC) +#define REQ_META (1ULL << __REQ_META) +#define REQ_PRIO (1ULL << __REQ_PRIO) + +#define REQ_NOMERGE_FLAGS (REQ_PREFLUSH | REQ_FUA) + +#define bio_op(bio) \ + ((bio)->bi_opf & REQ_OP_MASK) + +static inline void bio_set_op_attrs(struct bio *bio, unsigned op, + unsigned op_flags) +{ + bio->bi_opf = op | op_flags; +} + +#define REQ_RAHEAD (1ULL << __REQ_RAHEAD) +#define REQ_THROTTLED (1ULL << __REQ_THROTTLED) + +#define REQ_FUA (1ULL << __REQ_FUA) +#define REQ_PREFLUSH (1ULL << __REQ_PREFLUSH) + +#define RW_MASK REQ_OP_WRITE + +#define READ REQ_OP_READ +#define WRITE REQ_OP_WRITE + +#define READ_SYNC REQ_SYNC +#define WRITE_SYNC (REQ_SYNC) +#define WRITE_ODIRECT REQ_SYNC +#define WRITE_FLUSH (REQ_SYNC | REQ_PREFLUSH) +#define WRITE_FUA (REQ_SYNC | REQ_FUA) +#define WRITE_FLUSH_FUA (REQ_SYNC | REQ_PREFLUSH | REQ_FUA) + +#endif /* __LINUX_BLK_TYPES_H */ |