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-rw-r--r--include/linux/bio.h125
1 files changed, 78 insertions, 47 deletions
diff --git a/include/linux/bio.h b/include/linux/bio.h
index 7fc5606e6ea5..4d379c8250ae 100644
--- a/include/linux/bio.h
+++ b/include/linux/bio.h
@@ -138,55 +138,83 @@ struct bio {
#define BIO_POOL_IDX(bio) ((bio)->bi_flags >> BIO_POOL_OFFSET)
/*
- * bio bi_rw flags
- *
- * bit 0 -- data direction
- * If not set, bio is a read from device. If set, it's a write to device.
- * bit 1 -- fail fast device errors
- * bit 2 -- fail fast transport errors
- * bit 3 -- fail fast driver errors
- * bit 4 -- rw-ahead when set
- * bit 5 -- barrier
- * Insert a serialization point in the IO queue, forcing previously
- * submitted IO to be completed before this one is issued.
- * bit 6 -- synchronous I/O hint.
- * bit 7 -- Unplug the device immediately after submitting this bio.
- * bit 8 -- metadata request
- * Used for tracing to differentiate metadata and data IO. May also
- * get some preferential treatment in the IO scheduler
- * bit 9 -- discard sectors
- * Informs the lower level device that this range of sectors is no longer
- * used by the file system and may thus be freed by the device. Used
- * for flash based storage.
- * Don't want driver retries for any fast fail whatever the reason.
- * bit 10 -- Tell the IO scheduler not to wait for more requests after this
- one has been submitted, even if it is a SYNC request.
+ * 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 bio_rw_flags {
- BIO_RW,
- BIO_RW_FAILFAST_DEV,
- BIO_RW_FAILFAST_TRANSPORT,
- BIO_RW_FAILFAST_DRIVER,
- /* above flags must match REQ_* */
- BIO_RW_AHEAD,
- BIO_RW_BARRIER,
- BIO_RW_SYNCIO,
- BIO_RW_UNPLUG,
- BIO_RW_META,
- BIO_RW_DISCARD,
- BIO_RW_NOIDLE,
+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_IO_STAT, /* account I/O stat */
+ __REQ_MIXED_MERGE, /* merge of different types, fail separately */
+ __REQ_NR_BITS, /* stops here */
};
-/*
- * First four bits must match between bio->bi_rw and rq->cmd_flags, make
- * that explicit here.
- */
-#define BIO_RW_RQ_MASK 0xf
-
-static inline bool bio_rw_flagged(struct bio *bio, enum bio_rw_flags flag)
-{
- return (bio->bi_rw & (1 << flag)) != 0;
-}
+#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_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
@@ -211,7 +239,10 @@ static inline bool bio_rw_flagged(struct bio *bio, enum bio_rw_flags flag)
#define bio_offset(bio) bio_iovec((bio))->bv_offset
#define bio_segments(bio) ((bio)->bi_vcnt - (bio)->bi_idx)
#define bio_sectors(bio) ((bio)->bi_size >> 9)
-#define bio_empty_barrier(bio) (bio_rw_flagged(bio, BIO_RW_BARRIER) && !bio_has_data(bio) && !bio_rw_flagged(bio, BIO_RW_DISCARD))
+#define bio_empty_barrier(bio) \
+ ((bio->bi_rw & REQ_HARDBARRIER) && \
+ !bio_has_data(bio) && \
+ !(bio->bi_rw & REQ_DISCARD))
static inline unsigned int bio_cur_bytes(struct bio *bio)
{