[PATCH 2/5] nfsd4: return nfserr_symlink on v4 OPEN of non-regular file

["J. Bruce Fields" <bfields@redhat.com>]

Without this, an attempt to open a device special file without first
stat'ing it will fail.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
---
 fs/nfsd/nfsfh.c |   11 +++++++++++
 1 files changed, 11 insertions(+), 0 deletions(-)

diff --git a/fs/nfsd/nfsfh.c b/fs/nfsd/nfsfh.c
index 90c6aa6..cc8eb8d 100644
--- a/fs/nfsd/nfsfh.c
+++ b/fs/nfsd/nfsfh.c
@@ -69,6 +69,17 @@ nfsd_mode_check(struct svc_rqst *rqstp, umode_t mode, int type)
 			return nfserr_notdir;
 		else if ((mode & S_IFMT) == S_IFDIR)
 			return nfserr_isdir;
+		/*
+		 * err_symlink is our catch-all error in the v4 case; this
+		 * looks odd, but:
+		 *	- the comment next to ERR_SYMLINK in file is
+		 *	  "should be file/directory"
+		 *	- we happen to know this will cause the linux v4
+		 *	  client to do the right thing on attempts to open
+		 *	  something other than a regular file:
+		 */
+		else if (rqstp->rq_vers == 4)
+			return nfserr_symlink;
 		else
 			return nfserr_inval;
 	}
-- 
1.7.4.1