diff mbox

[7/9] rbd: kill rbd_is_lock_supported()

Message ID 1493112825-16403-8-git-send-email-idryomov@gmail.com (mailing list archive)
State New, archived
Headers show

Commit Message

Ilya Dryomov April 25, 2017, 9:33 a.m. UTC 
Currently the exclusive lock is acquired only if the mapping is
writable, i.e. an image HEAD mapped in rw mode.  This means that we
don't acquire the lock for executing a read from a snapshot or an image
HEAD mapped in ro mode, even if lock_on_read is set.  This is somewhat
weird and inconsistent with "no automatic exclusive lock transfers"
mode, where the lock is acquired unconditionally.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
---
 drivers/block/rbd.c | 14 +++-----------
 1 file changed, 3 insertions(+), 11 deletions(-)
diff mbox

Patch

diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c
index b859ce00ee1e..bcc43fb8a9b3 100644
--- a/drivers/block/rbd.c
+++ b/drivers/block/rbd.c
@@ -478,13 +478,6 @@  static int minor_to_rbd_dev_id(int minor)
 	return minor >> RBD_SINGLE_MAJOR_PART_SHIFT;
 }
 
-static bool rbd_is_lock_supported(struct rbd_device *rbd_dev)
-{
-	return (rbd_dev->header.features & RBD_FEATURE_EXCLUSIVE_LOCK) &&
-	       rbd_dev->spec->snap_id == CEPH_NOSNAP &&
-	       !rbd_dev->mapping.read_only;
-}
-
 static bool __rbd_is_lock_owner(struct rbd_device *rbd_dev)
 {
 	return rbd_dev->lock_state == RBD_LOCK_STATE_LOCKED ||
@@ -4052,10 +4045,6 @@  static void rbd_queue_workfn(struct work_struct *work)
 	if (op_type != OBJ_OP_READ) {
 		snapc = rbd_dev->header.snapc;
 		ceph_get_snap_context(snapc);
-		must_be_locked = rbd_is_lock_supported(rbd_dev);
-	} else {
-		must_be_locked = rbd_dev->opts->lock_on_read &&
-					rbd_is_lock_supported(rbd_dev);
 	}
 	up_read(&rbd_dev->header_rwsem);
 
@@ -4066,6 +4055,9 @@  static void rbd_queue_workfn(struct work_struct *work)
 		goto err_rq;
 	}
 
+	must_be_locked =
+	    (rbd_dev->header.features & RBD_FEATURE_EXCLUSIVE_LOCK) &&
+	    (op_type != OBJ_OP_READ || rbd_dev->opts->lock_on_read);
 	if (must_be_locked) {
 		down_read(&rbd_dev->lock_rwsem);
 		if (rbd_dev->lock_state != RBD_LOCK_STATE_LOCKED &&