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>

1 files changed, 4 insertions, 179 deletions

diff --git a/include/linux/bio.h b/include/linux/bio.h
index f655b54c9ef3..5274103434ad 100644
--- a/include/linux/bio.h
+++ b/include/linux/bio.h
@@ -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
@@ -41,184 +44,6 @@
 #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
  */
 #define BIO_PRIO_SHIFT  (8 * sizeof(unsigned long) - IOPRIO_BITS)