nfsd: clean up nfsd_mode_check()

Add some more comments, simplify logic, do & S_IFMT just once, name
"type" more helpfully.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>

diff --git a/fs/nfsd/nfsfh.c b/fs/nfsd/nfsfh.c
index 8cd49b9bf085dfa566e0042672e2d3680ca78518..c763de5c1157256e7d48a0f468b03d31c443551f 100644 (file)
--- a/fs/nfsd/nfsfh.c
+++ b/fs/nfsd/nfsfh.c
@@ -59,19 +59,25 @@ static int nfsd_acceptable(void *expv, struct dentry *dentry)
  * the write call).
  */
 static inline __be32
-nfsd_mode_check(struct svc_rqst *rqstp, umode_t mode, int type)
+nfsd_mode_check(struct svc_rqst *rqstp, umode_t mode, int requested)
 {
-       if (type > 0 && (mode & S_IFMT) != type) {
-               if (rqstp->rq_vers == 4 && (mode & S_IFMT) == S_IFLNK)
-                       return nfserr_symlink;
-               else if (type == S_IFDIR)
-                       return nfserr_notdir;
-               else if ((mode & S_IFMT) == S_IFDIR)
-                       return nfserr_isdir;
-               else
-                       return nfserr_inval;
-       }
-       return 0;
+       mode &= S_IFMT;
+
+       if (requested == 0) /* the caller doesn't care */
+               return nfs_ok;
+       if (mode == requested)
+               return nfs_ok;
+       /*
+        * v4 has an error more specific than err_notdir which we should
+        * return in preference to err_notdir:
+        */
+       if (rqstp->rq_vers == 4 && mode == S_IFLNK)
+               return nfserr_symlink;
+       if (requested == S_IFDIR)
+               return nfserr_notdir;
+       if (mode == S_IFDIR)
+               return nfserr_isdir;
+       return nfserr_inval;
 }
 
 static __be32 nfsd_setuser_and_check_port(struct svc_rqst *rqstp,