knfsd: nfsd: factor nfsd_lookup into 2 pieces

Factor nfsd_lookup into nfsd_lookup_dentry, which finds the right dentry and
export, and a second part which composes the filehandle (and which will later
check the security flavor on the new export).

No change in behavior.

Signed-off-by: "J. Bruce Fields" <bfields@citi.umich.edu>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 36 insertions, 19 deletions

diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
index 65043af232ee..627f460a4007 100644
--- a/fs/nfsd/vfs.c
+++ b/fs/nfsd/vfs.c
@@ -135,21 +135,10 @@ out:
         return err;
 }
 
-/*
- * Look up one component of a pathname.
- * N.B. After this call _both_ fhp and resfh need an fh_put
- *
- * If the lookup would cross a mountpoint, and the mounted filesystem
- * is exported to the client with NFSEXP_NOHIDE, then the lookup is
- * accepted as it stands and the mounted directory is
- * returned. Otherwise the covered directory is returned.
- * NOTE: this mountpoint crossing is not supported properly by all
- *   clients and is explicitly disallowed for NFSv3
- *      NeilBrown <neilb@cse.unsw.edu.au>
- */
 __be32
-nfsd_lookup(struct svc_rqst *rqstp, struct svc_fh *fhp, const char *name,
-                                        int len, struct svc_fh *resfh)
+nfsd_lookup_dentry(struct svc_rqst *rqstp, struct svc_fh *fhp,
+                   const char *name, int len,
+                   struct svc_export **exp_ret, struct dentry **dentry_ret)
 {
         struct svc_export       *exp;
         struct dentry           *dparent;
@@ -219,6 +208,38 @@ nfsd_lookup(struct svc_rqst *rqstp, struct svc_fh *fhp, const char *name,
                         }
                 }
         }
+        *dentry_ret = dentry;
+        *exp_ret = exp;
+        return 0;
+
+out_nfserr:
+        exp_put(exp);
+        return nfserrno(host_err);
+}
+
+/*
+ * Look up one component of a pathname.
+ * N.B. After this call _both_ fhp and resfh need an fh_put
+ *
+ * If the lookup would cross a mountpoint, and the mounted filesystem
+ * is exported to the client with NFSEXP_NOHIDE, then the lookup is
+ * accepted as it stands and the mounted directory is
+ * returned. Otherwise the covered directory is returned.
+ * NOTE: this mountpoint crossing is not supported properly by all
+ *   clients and is explicitly disallowed for NFSv3
+ *      NeilBrown <neilb@cse.unsw.edu.au>
+ */
+__be32
+nfsd_lookup(struct svc_rqst *rqstp, struct svc_fh *fhp, const char *name,
+                                        int len, struct svc_fh *resfh)
+{
+        struct svc_export       *exp;
+        struct dentry           *dentry;
+        __be32 err;
+
+        err = nfsd_lookup_dentry(rqstp, fhp, name, len, &exp, &dentry);
+        if (err)
+                return err;
         /*
          * Note: we compose the file handle now, but as the
          * dentry may be negative, it may need to be updated.
@@ -227,15 +248,11 @@ nfsd_lookup(struct svc_rqst *rqstp, struct svc_fh *fhp, const char *name,
         if (!err && !dentry->d_inode)
                 err = nfserr_noent;
         dput(dentry);
-out:
         exp_put(exp);
         return err;
-
-out_nfserr:
-        err = nfserrno(host_err);
-        goto out;
 }
 
+
 /*
  * Set various file attributes.
  * N.B. After this call fhp needs an fh_put