[Cluster-devel] [RESEND dlm/next 03/16] fs: dlm: handle -EBUSY as first for lock validation

[Alexander Aring]

In case of lock args validation we should at first check on -EBUSY then
on -EINVAL. The -EINVAL conditions checks against lkb state variables
which are not stable in case something is in -EBUSY lkb condition state
e.g. lkb->lkb_grmode. This patch checks at first if -EBUSY condition is
not met, then it's will check on -EINVAL condition.

Cc: stable at vger.kernel.org
Signed-off-by: Alexander Aring <aahringo at redhat.com>
---
 fs/dlm/lock.c | 18 +++++++++---------
 1 file changed, 9 insertions(+), 9 deletions(-)

diff --git a/fs/dlm/lock.c b/fs/dlm/lock.c
index dac7eb75dba9..c23413da40f5 100644
--- a/fs/dlm/lock.c
+++ b/fs/dlm/lock.c
@@ -2864,17 +2864,9 @@ static int set_unlock_args(uint32_t flags, void *astarg, struct dlm_args *args)
 static int validate_lock_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
 			      struct dlm_args *args)
 {
-	int rv = -EINVAL;
+	int rv = -EBUSY;
 
 	if (args->flags & DLM_LKF_CONVERT) {
-		if (lkb->lkb_flags & DLM_IFL_MSTCPY)
-			goto out;
-
-		if (args->flags & DLM_LKF_QUECVT &&
-		    !__quecvt_compat_matrix[lkb->lkb_grmode+1][args->mode+1])
-			goto out;
-
-		rv = -EBUSY;
 		if (lkb->lkb_status != DLM_LKSTS_GRANTED)
 			goto out;
 
@@ -2884,6 +2876,14 @@ static int validate_lock_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
 
 		if (is_overlap(lkb))
 			goto out;
+
+		rv = -EINVAL;
+		if (lkb->lkb_flags & DLM_IFL_MSTCPY)
+			goto out;
+
+		if (args->flags & DLM_LKF_QUECVT &&
+		    !__quecvt_compat_matrix[lkb->lkb_grmode+1][args->mode+1])
+			goto out;
 	}
 
 	lkb->lkb_exflags = args->flags;
-- 
2.31.1