SUNRPC: Add a field to track the number of kernel users of an rpc_pipe

This allows us to correctly deduce when we need to remove the pipe.

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

2 files changed, 9 insertions, 4 deletions

diff --git a/include/linux/sunrpc/rpc_pipe_fs.h b/include/linux/sunrpc/rpc_pipe_fs.h
index 430cea104817..51b977a4ca20 100644
--- a/include/linux/sunrpc/rpc_pipe_fs.h
+++ b/include/linux/sunrpc/rpc_pipe_fs.h
@@ -27,6 +27,7 @@ struct rpc_inode {
         int pipelen;
         int nreaders;
         int nwriters;
+        int nkern_readwriters;
         wait_queue_head_t waitq;
 #define RPC_PIPE_WAIT_FOR_OPEN  1
         int flags;
diff --git a/net/sunrpc/rpc_pipe.c b/net/sunrpc/rpc_pipe.c
index e5fd796e897e..e787b6a43eee 100644
--- a/net/sunrpc/rpc_pipe.c
+++ b/net/sunrpc/rpc_pipe.c
@@ -737,6 +737,7 @@ rpc_mkpipe(struct dentry *parent, const char *name, void *private, struct rpc_pi
                         dput (dentry);
                         dentry = ERR_PTR(-EBUSY);
                 }
+                rpci->nkern_readwriters++;
                 goto out;
         }
         inode = rpc_get_inode(dir->i_sb, S_IFIFO | S_IRUSR | S_IWUSR);
@@ -749,6 +750,7 @@ rpc_mkpipe(struct dentry *parent, const char *name, void *private, struct rpc_pi
         rpci->private = private;
         rpci->flags = flags;
         rpci->ops = ops;
+        rpci->nkern_readwriters = 1;
         inode_dir_notify(dir, DN_CREATE);
         dget(dentry);
 out:
@@ -773,10 +775,12 @@ rpc_unlink(struct dentry *dentry)
         parent = dget_parent(dentry);
         dir = parent->d_inode;
         mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
-        rpc_close_pipes(dentry->d_inode);
-        error = simple_unlink(dir, dentry);
-        if (!error)
-                d_delete(dentry);
+        if (--RPC_I(dentry->d_inode)->nkern_readwriters == 0) {
+                rpc_close_pipes(dentry->d_inode);
+                error = simple_unlink(dir, dentry);
+                if (!error)
+                        d_delete(dentry);
+        }
         dput(dentry);
         mutex_unlock(&dir->i_mutex);
         dput(parent);