SUNRPC: Fix a 'Busy inodes' error in rpc_pipefs

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

4 files changed, 35 insertions, 14 deletions

diff --git a/include/linux/sunrpc/clnt.h b/include/linux/sunrpc/clnt.h
index e37c06128e51..8fe9f35eba31 100644
--- a/include/linux/sunrpc/clnt.h
+++ b/include/linux/sunrpc/clnt.h
@@ -60,6 +60,7 @@ struct rpc_clnt {
         int                     cl_nodelen;     /* nodename length */
         char                    cl_nodename[UNX_MAXNODENAME];
         char                    cl_pathname[30];/* Path in rpc_pipe_fs */
+        struct vfsmount *       cl_vfsmnt;
         struct dentry *         cl_dentry;      /* inode */
         struct rpc_clnt *       cl_parent;      /* Points to parent of clones */
         struct rpc_rtt          cl_rtt_default;
diff --git a/include/linux/sunrpc/rpc_pipe_fs.h b/include/linux/sunrpc/rpc_pipe_fs.h
index 63929349571f..2c2189cb30aa 100644
--- a/include/linux/sunrpc/rpc_pipe_fs.h
+++ b/include/linux/sunrpc/rpc_pipe_fs.h
@@ -45,6 +45,8 @@ extern struct dentry *rpc_mkdir(char *, struct rpc_clnt *);
 extern int rpc_rmdir(char *);
 extern struct dentry *rpc_mkpipe(char *, void *, struct rpc_pipe_ops *, int flags);
 extern int rpc_unlink(char *);
+extern struct vfsmount *rpc_get_mount(void);
+extern void rpc_put_mount(void);
 
 #endif
 #endif
diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c
index 0bb23e8e9d0c..9f775302d1df 100644
--- a/net/sunrpc/clnt.c
+++ b/net/sunrpc/clnt.c
@@ -70,8 +70,15 @@ rpc_setup_pipedir(struct rpc_clnt *clnt, char *dir_name)
         static uint32_t clntid;
         int error;
 
+        clnt->cl_vfsmnt = ERR_PTR(-ENOENT);
+        clnt->cl_dentry = ERR_PTR(-ENOENT);
         if (dir_name == NULL)
                 return 0;
+
+        clnt->cl_vfsmnt = rpc_get_mount();
+        if (IS_ERR(clnt->cl_vfsmnt))
+                return PTR_ERR(clnt->cl_vfsmnt);
+
         for (;;) {
                 snprintf(clnt->cl_pathname, sizeof(clnt->cl_pathname),
                                 "%s/clnt%x", dir_name,
@@ -84,6 +91,7 @@ rpc_setup_pipedir(struct rpc_clnt *clnt, char *dir_name)
                 if (error != -EEXIST) {
                         printk(KERN_INFO "RPC: Couldn't create pipefs entry %s, error %d\n",
                                         clnt->cl_pathname, error);
+                        rpc_put_mount();
                         return error;
                 }
         }
@@ -175,7 +183,11 @@ rpc_new_client(struct rpc_xprt *xprt, char *servname,
         return clnt;
 
 out_no_auth:
-        rpc_rmdir(clnt->cl_pathname);
+        if (!IS_ERR(clnt->cl_dentry)) {
+                rpc_rmdir(clnt->cl_pathname);
+                dput(clnt->cl_dentry);
+                rpc_put_mount();
+        }
 out_no_path:
         if (clnt->cl_server != clnt->cl_inline_name)
                 kfree(clnt->cl_server);
@@ -240,13 +252,15 @@ rpc_clone_client(struct rpc_clnt *clnt)
         new->cl_autobind = 0;
         new->cl_oneshot = 0;
         new->cl_dead = 0;
-        dget(new->cl_dentry);
+        if (!IS_ERR(new->cl_dentry)) {
+                dget(new->cl_dentry);
+                rpc_get_mount();
+        }
         rpc_init_rtt(&new->cl_rtt_default, clnt->cl_xprt->timeout.to_initval);
         if (new->cl_auth)
                 atomic_inc(&new->cl_auth->au_count);
         new->cl_pmap            = &new->cl_pmap_default;
         new->cl_metrics         = rpc_alloc_iostats(clnt);
-        rpc_init_wait_queue(&new->cl_pmap_default.pm_bindwait, "bindwait");
         return new;
 out_no_clnt:
         printk(KERN_INFO "RPC: out of memory in %s\n", __FUNCTION__);
@@ -318,8 +332,10 @@ rpc_destroy_client(struct rpc_clnt *clnt)
 out_free:
         rpc_free_iostats(clnt->cl_metrics);
         clnt->cl_metrics = NULL;
-        if (clnt->cl_dentry)
+        if (!IS_ERR(clnt->cl_dentry)) {
                 dput(clnt->cl_dentry);
+                rpc_put_mount();
+        }
         kfree(clnt);
         return 0;
 }
diff --git a/net/sunrpc/rpc_pipe.c b/net/sunrpc/rpc_pipe.c
index 72b22172f0af..391d2bfc71aa 100644
--- a/net/sunrpc/rpc_pipe.c
+++ b/net/sunrpc/rpc_pipe.c
@@ -435,14 +435,17 @@ static struct rpc_filelist authfiles[] = {
         },
 };
 
-static int
-rpc_get_mount(void)
+struct vfsmount *rpc_get_mount(void)
 {
-        return simple_pin_fs("rpc_pipefs", &rpc_mount, &rpc_mount_count);
+        int err;
+
+        err = simple_pin_fs("rpc_pipefs", &rpc_mount, &rpc_mount_count);
+        if (err != 0)
+                return ERR_PTR(err);
+        return rpc_mount;
 }
 
-static void
-rpc_put_mount(void)
+void rpc_put_mount(void)
 {
         simple_release_fs(&rpc_mount, &rpc_mount_count);
 }
@@ -452,12 +455,13 @@ rpc_lookup_parent(char *path, struct nameidata *nd)
 {
         if (path[0] == '\0')
                 return -ENOENT;
-        if (rpc_get_mount()) {
+        nd->mnt = rpc_get_mount();
+        if (IS_ERR(nd->mnt)) {
                 printk(KERN_WARNING "%s: %s failed to mount "
                                "pseudofilesystem \n", __FILE__, __FUNCTION__);
-                return -ENODEV;
+                return PTR_ERR(nd->mnt);
         }
-        nd->mnt = mntget(rpc_mount);
+        mntget(nd->mnt);
         nd->dentry = dget(rpc_mount->mnt_root);
         nd->last_type = LAST_ROOT;
         nd->flags = LOOKUP_PARENT;
@@ -594,7 +598,6 @@ __rpc_mkdir(struct inode *dir, struct dentry *dentry)
         d_instantiate(dentry, inode);
         dir->i_nlink++;
         inode_dir_notify(dir, DN_CREATE);
-        rpc_get_mount();
         return 0;
 out_err:
         printk(KERN_WARNING "%s: %s failed to allocate inode for dentry %s\n",
@@ -615,7 +618,6 @@ __rpc_rmdir(struct inode *dir, struct dentry *dentry)
         if (!error) {
                 inode_dir_notify(dir, DN_DELETE);
                 d_drop(dentry);
-                rpc_put_mount();
         }
         return 0;
 }