block: Clean up special command handling logic
Remove special-casing of non-rw fs style requests (discard). The nomerge
flags are consolidated in blk_types.h, and rq_mergeable() and
bio_mergeable() have been modified to use them.
bio_is_rw() is used in place of bio_has_data() a few places. This is
done to to distinguish true reads and writes from other fs type requests
that carry a payload (e.g. write same).
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/include/linux/bio.h b/include/linux/bio.h
index 52b9cbc..e54305c 100644
--- a/include/linux/bio.h
+++ b/include/linux/bio.h
@@ -386,9 +386,28 @@
/*
* Check whether this bio carries any data or not. A NULL bio is allowed.
*/
-static inline int bio_has_data(struct bio *bio)
+static inline bool bio_has_data(struct bio *bio)
{
- return bio && bio->bi_io_vec != NULL;
+ if (bio && bio->bi_vcnt)
+ return true;
+
+ return false;
+}
+
+static inline bool bio_is_rw(struct bio *bio)
+{
+ if (!bio_has_data(bio))
+ return false;
+
+ return true;
+}
+
+static inline bool bio_mergeable(struct bio *bio)
+{
+ if (bio->bi_rw & REQ_NOMERGE_FLAGS)
+ return false;
+
+ return true;
}
/*
diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h
index 3eefbb2..1b22966 100644
--- a/include/linux/blk_types.h
+++ b/include/linux/blk_types.h
@@ -194,6 +194,10 @@
REQ_DISCARD | REQ_NOIDLE | REQ_FLUSH | REQ_FUA | REQ_SECURE)
#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_FLUSH | REQ_FUA)
+
#define REQ_RAHEAD (1 << __REQ_RAHEAD)
#define REQ_THROTTLED (1 << __REQ_THROTTLED)
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 4a2ab7c..3a6fea7 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -540,8 +540,7 @@
#define blk_account_rq(rq) \
(((rq)->cmd_flags & REQ_STARTED) && \
- ((rq)->cmd_type == REQ_TYPE_FS || \
- ((rq)->cmd_flags & REQ_DISCARD)))
+ ((rq)->cmd_type == REQ_TYPE_FS))
#define blk_pm_request(rq) \
((rq)->cmd_type == REQ_TYPE_PM_SUSPEND || \
@@ -595,17 +594,16 @@
rl->flags &= ~flag;
}
+static inline bool rq_mergeable(struct request *rq)
+{
+ if (rq->cmd_type != REQ_TYPE_FS)
+ return false;
-/*
- * mergeable request must not have _NOMERGE or _BARRIER bit set, nor may
- * it already be started by driver.
- */
-#define RQ_NOMERGE_FLAGS \
- (REQ_NOMERGE | REQ_STARTED | REQ_SOFTBARRIER | REQ_FLUSH | REQ_FUA | REQ_DISCARD)
-#define rq_mergeable(rq) \
- (!((rq)->cmd_flags & RQ_NOMERGE_FLAGS) && \
- (((rq)->cmd_flags & REQ_DISCARD) || \
- (rq)->cmd_type == REQ_TYPE_FS))
+ if (rq->cmd_flags & REQ_NOMERGE_FLAGS)
+ return false;
+
+ return true;
+}
/*
* q->prep_rq_fn return values