bio, fs: separate out bio_types.h and define READ/WRITE constants in terms of BIO_RW_* flags

linux/fs.h hard coded READ/WRITE constants which should match BIO_RW_*
flags.  This is fragile and caused breakage during BIO_RW_* flag
rearrangement.  The hardcoding is to avoid include dependency hell.

Create linux/bio_types.h which contatins definitions for bio data
structures and flags and include it from bio.h and fs.h, and make fs.h
define all READ/WRITE related constants in terms of BIO_RW_* flags.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
This commit is contained in:
Tejun Heo 2010-08-03 13:14:58 +02:00 committed by Jens Axboe
parent aca27ba961
commit 7cc015811e
3 changed files with 204 additions and 187 deletions

View file

@ -9,7 +9,7 @@
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
*
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
@ -28,6 +28,9 @@
#include <asm/io.h>
/* struct bio, bio_vec and BIO_* flags are defined in blk_types.h */
#include <linux/blk_types.h>
#define BIO_DEBUG
#ifdef BIO_DEBUG
@ -40,184 +43,6 @@
#define BIO_MAX_SIZE (BIO_MAX_PAGES << PAGE_CACHE_SHIFT)
#define BIO_MAX_SECTORS (BIO_MAX_SIZE >> 9)
/*
* was unsigned short, but we might as well be ready for > 64kB I/O pages
*/
struct bio_vec {
struct page *bv_page;
unsigned int bv_len;
unsigned int bv_offset;
};
struct bio_set;
struct bio;
struct bio_integrity_payload;
typedef void (bio_end_io_t) (struct bio *, int);
typedef void (bio_destructor_t) (struct bio *);
/*
* main unit of I/O for the block layer and lower layers (ie drivers and
* stacking drivers)
*/
struct bio {
sector_t bi_sector; /* device address in 512 byte
sectors */
struct bio *bi_next; /* request queue link */
struct block_device *bi_bdev;
unsigned long bi_flags; /* status, command, etc */
unsigned long bi_rw; /* bottom bits READ/WRITE,
* top bits priority
*/
unsigned short bi_vcnt; /* how many bio_vec's */
unsigned short bi_idx; /* current index into bvl_vec */
/* Number of segments in this BIO after
* physical address coalescing is performed.
*/
unsigned int bi_phys_segments;
unsigned int bi_size; /* residual I/O count */
/*
* 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;
unsigned int bi_max_vecs; /* max bvl_vecs we can hold */
unsigned int bi_comp_cpu; /* completion CPU */
atomic_t bi_cnt; /* pin count */
struct bio_vec *bi_io_vec; /* the actual vec list */
bio_end_io_t *bi_end_io;
void *bi_private;
#if defined(CONFIG_BLK_DEV_INTEGRITY)
struct bio_integrity_payload *bi_integrity; /* data integrity */
#endif
bio_destructor_t *bi_destructor; /* destructor */
/*
* 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];
};
/*
* bio flags
*/
#define BIO_UPTODATE 0 /* ok after I/O completion */
#define BIO_RW_BLOCK 1 /* RW_AHEAD set, and read/write would block */
#define BIO_EOF 2 /* out-out-bounds error */
#define BIO_SEG_VALID 3 /* bi_phys_segments valid */
#define BIO_CLONED 4 /* doesn't own data */
#define BIO_BOUNCED 5 /* bio is a bounce bio */
#define BIO_USER_MAPPED 6 /* contains user pages */
#define BIO_EOPNOTSUPP 7 /* not supported */
#define BIO_CPU_AFFINE 8 /* complete bio on same CPU as submitted */
#define BIO_NULL_MAPPED 9 /* contains invalid user pages */
#define BIO_FS_INTEGRITY 10 /* fs owns integrity data, not block layer */
#define BIO_QUIET 11 /* Make BIO Quiet */
#define bio_flagged(bio, flag) ((bio)->bi_flags & (1 << (flag)))
/*
* top 4 bits of bio flags indicate the pool this bio came from
*/
#define BIO_POOL_BITS (4)
#define BIO_POOL_NONE ((1UL << BIO_POOL_BITS) - 1)
#define BIO_POOL_OFFSET (BITS_PER_LONG - BIO_POOL_BITS)
#define BIO_POOL_MASK (1UL << BIO_POOL_OFFSET)
#define BIO_POOL_IDX(bio) ((bio)->bi_flags >> BIO_POOL_OFFSET)
/*
* Request flags. For use in the cmd_flags field of struct request, and in
* bi_rw of struct bio. Note that some flags are only valid in either one.
*/
enum rq_flag_bits {
/* common flags */
__REQ_WRITE, /* not set, read. set, write */
__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_HARDBARRIER, /* may not be passed by drive either */
__REQ_SYNC, /* request is sync (sync write or read) */
__REQ_META, /* metadata io request */
__REQ_DISCARD, /* request to discard sectors */
__REQ_NOIDLE, /* don't anticipate more IO after this one */
/* bio only flags */
__REQ_UNPLUG, /* unplug the immediately after submission */
__REQ_RAHEAD, /* read ahead, can fail anytime */
/* request only flags */
__REQ_SORTED, /* elevator knows about this request */
__REQ_SOFTBARRIER, /* may not be passed by ioscheduler */
__REQ_FUA, /* forced unit access */
__REQ_NOMERGE, /* don't touch this for merging */
__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 */
__REQ_ORDERED_COLOR, /* is before or after barrier */
__REQ_ALLOCED, /* request came from our alloc pool */
__REQ_COPY_USER, /* contains copies of user pages */
__REQ_INTEGRITY, /* integrity metadata has been remapped */
__REQ_FLUSH, /* request for cache flush */
__REQ_IO_STAT, /* account I/O stat */
__REQ_MIXED_MERGE, /* merge of different types, fail separately */
__REQ_NR_BITS, /* stops here */
};
#define REQ_WRITE (1 << __REQ_WRITE)
#define REQ_FAILFAST_DEV (1 << __REQ_FAILFAST_DEV)
#define REQ_FAILFAST_TRANSPORT (1 << __REQ_FAILFAST_TRANSPORT)
#define REQ_FAILFAST_DRIVER (1 << __REQ_FAILFAST_DRIVER)
#define REQ_HARDBARRIER (1 << __REQ_HARDBARRIER)
#define REQ_SYNC (1 << __REQ_SYNC)
#define REQ_META (1 << __REQ_META)
#define REQ_DISCARD (1 << __REQ_DISCARD)
#define REQ_NOIDLE (1 << __REQ_NOIDLE)
#define REQ_FAILFAST_MASK \
(REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT | REQ_FAILFAST_DRIVER)
#define REQ_COMMON_MASK \
(REQ_WRITE | REQ_FAILFAST_MASK | REQ_HARDBARRIER | REQ_SYNC | \
REQ_META| REQ_DISCARD | REQ_NOIDLE)
#define REQ_UNPLUG (1 << __REQ_UNPLUG)
#define REQ_RAHEAD (1 << __REQ_RAHEAD)
#define REQ_SORTED (1 << __REQ_SORTED)
#define REQ_SOFTBARRIER (1 << __REQ_SOFTBARRIER)
#define REQ_FUA (1 << __REQ_FUA)
#define REQ_NOMERGE (1 << __REQ_NOMERGE)
#define REQ_STARTED (1 << __REQ_STARTED)
#define REQ_DONTPREP (1 << __REQ_DONTPREP)
#define REQ_QUEUED (1 << __REQ_QUEUED)
#define REQ_ELVPRIV (1 << __REQ_ELVPRIV)
#define REQ_FAILED (1 << __REQ_FAILED)
#define REQ_QUIET (1 << __REQ_QUIET)
#define REQ_PREEMPT (1 << __REQ_PREEMPT)
#define REQ_ORDERED_COLOR (1 << __REQ_ORDERED_COLOR)
#define REQ_ALLOCED (1 << __REQ_ALLOCED)
#define REQ_COPY_USER (1 << __REQ_COPY_USER)
#define REQ_INTEGRITY (1 << __REQ_INTEGRITY)
#define REQ_FLUSH (1 << __REQ_FLUSH)
#define REQ_IO_STAT (1 << __REQ_IO_STAT)
#define REQ_MIXED_MERGE (1 << __REQ_MIXED_MERGE)
/*
* upper 16 bits of bi_rw define the io priority of this bio
*/

193
include/linux/blk_types.h Normal file
View file

@ -0,0 +1,193 @@
/*
* 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
#ifdef CONFIG_BLOCK
#include <linux/types.h>
struct bio_set;
struct bio;
struct bio_integrity_payload;
struct page;
struct block_device;
typedef void (bio_end_io_t) (struct bio *, int);
typedef void (bio_destructor_t) (struct bio *);
/*
* was unsigned short, but we might as well be ready for > 64kB I/O pages
*/
struct bio_vec {
struct page *bv_page;
unsigned int bv_len;
unsigned int bv_offset;
};
/*
* main unit of I/O for the block layer and lower layers (ie drivers and
* stacking drivers)
*/
struct bio {
sector_t bi_sector; /* device address in 512 byte
sectors */
struct bio *bi_next; /* request queue link */
struct block_device *bi_bdev;
unsigned long bi_flags; /* status, command, etc */
unsigned long bi_rw; /* bottom bits READ/WRITE,
* top bits priority
*/
unsigned short bi_vcnt; /* how many bio_vec's */
unsigned short bi_idx; /* current index into bvl_vec */
/* Number of segments in this BIO after
* physical address coalescing is performed.
*/
unsigned int bi_phys_segments;
unsigned int bi_size; /* residual I/O count */
/*
* 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;
unsigned int bi_max_vecs; /* max bvl_vecs we can hold */
unsigned int bi_comp_cpu; /* completion CPU */
atomic_t bi_cnt; /* pin count */
struct bio_vec *bi_io_vec; /* the actual vec list */
bio_end_io_t *bi_end_io;
void *bi_private;
#if defined(CONFIG_BLK_DEV_INTEGRITY)
struct bio_integrity_payload *bi_integrity; /* data integrity */
#endif
bio_destructor_t *bi_destructor; /* destructor */
/*
* 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];
};
/*
* bio flags
*/
#define BIO_UPTODATE 0 /* ok after I/O completion */
#define BIO_RW_BLOCK 1 /* RW_AHEAD set, and read/write would block */
#define BIO_EOF 2 /* out-out-bounds error */
#define BIO_SEG_VALID 3 /* bi_phys_segments valid */
#define BIO_CLONED 4 /* doesn't own data */
#define BIO_BOUNCED 5 /* bio is a bounce bio */
#define BIO_USER_MAPPED 6 /* contains user pages */
#define BIO_EOPNOTSUPP 7 /* not supported */
#define BIO_CPU_AFFINE 8 /* complete bio on same CPU as submitted */
#define BIO_NULL_MAPPED 9 /* contains invalid user pages */
#define BIO_FS_INTEGRITY 10 /* fs owns integrity data, not block layer */
#define BIO_QUIET 11 /* Make BIO Quiet */
#define bio_flagged(bio, flag) ((bio)->bi_flags & (1 << (flag)))
/*
* top 4 bits of bio flags indicate the pool this bio came from
*/
#define BIO_POOL_BITS (4)
#define BIO_POOL_NONE ((1UL << BIO_POOL_BITS) - 1)
#define BIO_POOL_OFFSET (BITS_PER_LONG - BIO_POOL_BITS)
#define BIO_POOL_MASK (1UL << BIO_POOL_OFFSET)
#define BIO_POOL_IDX(bio) ((bio)->bi_flags >> BIO_POOL_OFFSET)
/*
* Request flags. For use in the cmd_flags field of struct request, and in
* bi_rw of struct bio. Note that some flags are only valid in either one.
*/
enum rq_flag_bits {
/* common flags */
__REQ_WRITE, /* not set, read. set, write */
__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_HARDBARRIER, /* may not be passed by drive either */
__REQ_SYNC, /* request is sync (sync write or read) */
__REQ_META, /* metadata io request */
__REQ_DISCARD, /* request to discard sectors */
__REQ_NOIDLE, /* don't anticipate more IO after this one */
/* bio only flags */
__REQ_UNPLUG, /* unplug the immediately after submission */
__REQ_RAHEAD, /* read ahead, can fail anytime */
/* request only flags */
__REQ_SORTED, /* elevator knows about this request */
__REQ_SOFTBARRIER, /* may not be passed by ioscheduler */
__REQ_FUA, /* forced unit access */
__REQ_NOMERGE, /* don't touch this for merging */
__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 */
__REQ_ORDERED_COLOR, /* is before or after barrier */
__REQ_ALLOCED, /* request came from our alloc pool */
__REQ_COPY_USER, /* contains copies of user pages */
__REQ_INTEGRITY, /* integrity metadata has been remapped */
__REQ_FLUSH, /* request for cache flush */
__REQ_IO_STAT, /* account I/O stat */
__REQ_MIXED_MERGE, /* merge of different types, fail separately */
__REQ_NR_BITS, /* stops here */
};
#define REQ_WRITE (1 << __REQ_WRITE)
#define REQ_FAILFAST_DEV (1 << __REQ_FAILFAST_DEV)
#define REQ_FAILFAST_TRANSPORT (1 << __REQ_FAILFAST_TRANSPORT)
#define REQ_FAILFAST_DRIVER (1 << __REQ_FAILFAST_DRIVER)
#define REQ_HARDBARRIER (1 << __REQ_HARDBARRIER)
#define REQ_SYNC (1 << __REQ_SYNC)
#define REQ_META (1 << __REQ_META)
#define REQ_DISCARD (1 << __REQ_DISCARD)
#define REQ_NOIDLE (1 << __REQ_NOIDLE)
#define REQ_FAILFAST_MASK \
(REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT | REQ_FAILFAST_DRIVER)
#define REQ_COMMON_MASK \
(REQ_WRITE | REQ_FAILFAST_MASK | REQ_HARDBARRIER | REQ_SYNC | \
REQ_META| REQ_DISCARD | REQ_NOIDLE)
#define REQ_UNPLUG (1 << __REQ_UNPLUG)
#define REQ_RAHEAD (1 << __REQ_RAHEAD)
#define REQ_SORTED (1 << __REQ_SORTED)
#define REQ_SOFTBARRIER (1 << __REQ_SOFTBARRIER)
#define REQ_FUA (1 << __REQ_FUA)
#define REQ_NOMERGE (1 << __REQ_NOMERGE)
#define REQ_STARTED (1 << __REQ_STARTED)
#define REQ_DONTPREP (1 << __REQ_DONTPREP)
#define REQ_QUEUED (1 << __REQ_QUEUED)
#define REQ_ELVPRIV (1 << __REQ_ELVPRIV)
#define REQ_FAILED (1 << __REQ_FAILED)
#define REQ_QUIET (1 << __REQ_QUIET)
#define REQ_PREEMPT (1 << __REQ_PREEMPT)
#define REQ_ORDERED_COLOR (1 << __REQ_ORDERED_COLOR)
#define REQ_ALLOCED (1 << __REQ_ALLOCED)
#define REQ_COPY_USER (1 << __REQ_COPY_USER)
#define REQ_INTEGRITY (1 << __REQ_INTEGRITY)
#define REQ_FLUSH (1 << __REQ_FLUSH)
#define REQ_IO_STAT (1 << __REQ_IO_STAT)
#define REQ_MIXED_MERGE (1 << __REQ_MIXED_MERGE)
#endif /* CONFIG_BLOCK */
#endif /* __LINUX_BLK_TYPES_H */

View file

@ -8,6 +8,7 @@
#include <linux/limits.h>
#include <linux/ioctl.h>
#include <linux/blk_types.h>
/*
* It's silly to have NR_OPEN bigger than NR_FILE, but you can change
@ -117,7 +118,7 @@ struct inodes_stat_t {
* immediately wait on this read without caring about
* unplugging.
* READA Used for read-ahead operations. Lower priority, and the
* block layer could (in theory) choose to ignore this
* block layer could (in theory) choose to ignore this
* request if it runs into resource problems.
* WRITE A normal async write. Device will be plugged.
* SWRITE Like WRITE, but a special case for ll_rw_block() that
@ -144,13 +145,13 @@ struct inodes_stat_t {
* of this IO.
*
*/
#define RW_MASK 1
#define RWA_MASK 16
#define RW_MASK REQ_WRITE
#define RWA_MASK REQ_RAHEAD
#define READ 0
#define WRITE 1
#define READA 16 /* readahead - don't block if no resources */
#define SWRITE 17 /* for ll_rw_block(), wait for buffer lock */
#define WRITE RW_MASK
#define READA RWA_MASK
#define SWRITE (WRITE | READA)
#define READ_SYNC (READ | REQ_SYNC | REQ_UNPLUG)
#define READ_META (READ | REQ_META)
@ -2200,7 +2201,6 @@ static inline void insert_inode_hash(struct inode *inode) {
extern void file_move(struct file *f, struct list_head *list);
extern void file_kill(struct file *f);
#ifdef CONFIG_BLOCK
struct bio;
extern void submit_bio(int, struct bio *);
extern int bdev_read_only(struct block_device *);
#endif
@ -2267,7 +2267,6 @@ static inline int xip_truncate_page(struct address_space *mapping, loff_t from)
#endif
#ifdef CONFIG_BLOCK
struct bio;
typedef void (dio_submit_t)(int rw, struct bio *bio, struct inode *inode,
loff_t file_offset);
void dio_end_io(struct bio *bio, int error);