[patch 1/9] lockd: dont return EAGAIN for a permanent error

[Miklos Szeredi]

From: Miklos Szeredi <mszeredi@xxxxxxx>

Fix nlm_fopen() to return NLM_FAILED (or NLM_LCK_DENIED_NOLOCKS)
instead of NLM_LCK_DENIED.  The latter means the lock request failed
because of a conflicting lock (i.e. a temporary error), which is wrong
in this case.

Also fix the client to return ENOLCK instead of EAGAIN if a blocking
lock request returns with NLM_LOCK_DENIED.

Signed-off-by: Miklos Szeredi <mszeredi@xxxxxxx>
CC: Trond Myklebust <trond.myklebust@xxxxxxxxxx>
CC: "J. Bruce Fields" <bfields@xxxxxxxxxxxx>
---
 fs/lockd/clntproc.c |   10 +++++++++-
 fs/nfsd/lockd.c     |   13 +++++++++----
 2 files changed, 18 insertions(+), 5 deletions(-)

Index: linux-2.6/fs/lockd/clntproc.c
===================================================================
--- linux-2.6.orig/fs/lockd/clntproc.c	2008-05-15 17:54:30.000000000 +0200
+++ linux-2.6/fs/lockd/clntproc.c	2008-05-15 17:59:41.000000000 +0200
@@ -580,7 +580,15 @@ again:
 	}
 	if (status < 0)
 		goto out_unlock;
-	status = nlm_stat_to_errno(resp->status);
+	/*
+	 * EAGAIN doesn't make sense for sleeping locks, and in some
+	 * cases NLM_LCK_DENIED is returned for a permanent error.  So
+	 * turn it into an ENOLCK.
+	 */
+	if (resp->status == nlm_lck_denied && (fl_flags & FL_SLEEP))
+		status = -ENOLCK;
+	else
+		status = nlm_stat_to_errno(resp->status);
 out_unblock:
 	nlmclnt_finish_block(block);
 out:
Index: linux-2.6/fs/nfsd/lockd.c
===================================================================
--- linux-2.6.orig/fs/nfsd/lockd.c	2008-05-15 17:54:30.000000000 +0200
+++ linux-2.6/fs/nfsd/lockd.c	2008-05-15 17:57:45.000000000 +0200
@@ -19,6 +19,13 @@
 
 #define NFSDDBG_FACILITY		NFSDDBG_LOCKD
 
+#ifdef CONFIG_LOCKD_V4
+#define nlm_stale_fh	nlm4_stale_fh
+#define nlm_failed	nlm4_failed
+#else
+#define nlm_stale_fh	nlm_lck_denied_nolocks
+#define nlm_failed	nlm_lck_denied_nolocks
+#endif
 /*
  * Note: we hold the dentry use count while the file is open.
  */
@@ -47,12 +54,10 @@ nlm_fopen(struct svc_rqst *rqstp, struct
 		return 0;
 	case nfserr_dropit:
 		return nlm_drop_reply;
-#ifdef CONFIG_LOCKD_V4
 	case nfserr_stale:
-		return nlm4_stale_fh;
-#endif
+		return nlm_stale_fh;
 	default:
-		return nlm_lck_denied;
+		return nlm_failed;
 	}
 }
 

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