1 files changed, 26 insertions, 13 deletions

diff --git a/net/sunrpc/rpc_pipe.c b/net/sunrpc/rpc_pipe.c
index b67b2aecc4ff..ac9ee1590739 100644
--- a/net/sunrpc/rpc_pipe.c
+++ b/net/sunrpc/rpc_pipe.c
@@ -57,7 +57,7 @@ void rpc_pipefs_notifier_unregister(struct notifier_block *nb)
 }
 EXPORT_SYMBOL_GPL(rpc_pipefs_notifier_unregister);
 
-static void rpc_purge_list(struct rpc_pipe *pipe, struct list_head *head,
+static void rpc_purge_list(wait_queue_head_t *waitq, struct list_head *head,
                 void (*destroy_msg)(struct rpc_pipe_msg *), int err)
 {
         struct rpc_pipe_msg *msg;
@@ -70,7 +70,7 @@ static void rpc_purge_list(struct rpc_pipe *pipe, struct list_head *head,
                 msg->errno = err;
                 destroy_msg(msg);
         } while (!list_empty(head));
-        wake_up(&pipe->waitq);
+        wake_up(waitq);
 }
 
 static void
@@ -80,6 +80,7 @@ rpc_timeout_upcall_queue(struct work_struct *work)
         struct rpc_pipe *pipe =
                 container_of(work, struct rpc_pipe, queue_timeout.work);
         void (*destroy_msg)(struct rpc_pipe_msg *);
+        struct dentry *dentry;
 
         spin_lock(&pipe->lock);
         destroy_msg = pipe->ops->destroy_msg;
@@ -87,8 +88,13 @@ rpc_timeout_upcall_queue(struct work_struct *work)
                 list_splice_init(&pipe->pipe, &free_list);
                 pipe->pipelen = 0;
         }
+        dentry = dget(pipe->dentry);
         spin_unlock(&pipe->lock);
-        rpc_purge_list(pipe, &free_list, destroy_msg, -ETIMEDOUT);
+        if (dentry) {
+                rpc_purge_list(&RPC_I(dentry->d_inode)->waitq,
+                               &free_list, destroy_msg, -ETIMEDOUT);
+                dput(dentry);
+        }
 }
 
 ssize_t rpc_pipe_generic_upcall(struct file *filp, struct rpc_pipe_msg *msg,
@@ -125,6 +131,7 @@ int
 rpc_queue_upcall(struct rpc_pipe *pipe, struct rpc_pipe_msg *msg)
 {
         int res = -EPIPE;
+        struct dentry *dentry;
 
         spin_lock(&pipe->lock);
         if (pipe->nreaders) {
@@ -140,8 +147,12 @@ rpc_queue_upcall(struct rpc_pipe *pipe, struct rpc_pipe_msg *msg)
                 pipe->pipelen += msg->len;
                 res = 0;
         }
+        dentry = dget(pipe->dentry);
         spin_unlock(&pipe->lock);
-        wake_up(&pipe->waitq);
+        if (dentry) {
+                wake_up(&RPC_I(dentry->d_inode)->waitq);
+                dput(dentry);
+        }
         return res;
 }
 EXPORT_SYMBOL_GPL(rpc_queue_upcall);
@@ -168,7 +179,7 @@ rpc_close_pipes(struct inode *inode)
         pipe->pipelen = 0;
         pipe->dentry = NULL;
         spin_unlock(&pipe->lock);
-        rpc_purge_list(pipe, &free_list, pipe->ops->destroy_msg, -EPIPE);
+        rpc_purge_list(&RPC_I(inode)->waitq, &free_list, pipe->ops->destroy_msg, -EPIPE);
         pipe->nwriters = 0;
         if (need_release && pipe->ops->release_pipe)
                 pipe->ops->release_pipe(inode);
@@ -257,7 +268,7 @@ rpc_pipe_release(struct inode *inode, struct file *filp)
                         list_splice_init(&pipe->pipe, &free_list);
                         pipe->pipelen = 0;
                         spin_unlock(&pipe->lock);
-                        rpc_purge_list(pipe, &free_list,
+                        rpc_purge_list(&RPC_I(inode)->waitq, &free_list,
                                         pipe->ops->destroy_msg, -EAGAIN);
                 }
         }
@@ -330,16 +341,18 @@ rpc_pipe_write(struct file *filp, const char __user *buf, size_t len, loff_t *of
 static unsigned int
 rpc_pipe_poll(struct file *filp, struct poll_table_struct *wait)
 {
-        struct rpc_pipe *pipe = RPC_I(filp->f_path.dentry->d_inode)->pipe;
-        unsigned int mask = 0;
+        struct inode *inode = filp->f_path.dentry->d_inode;
+        struct rpc_inode *rpci = RPC_I(inode);
+        unsigned int mask = POLLOUT | POLLWRNORM;
 
-        poll_wait(filp, &pipe->waitq, wait);
+        poll_wait(filp, &rpci->waitq, wait);
 
-        mask = POLLOUT | POLLWRNORM;
-        if (pipe->dentry == NULL)
+        mutex_lock(&inode->i_mutex);
+        if (rpci->pipe == NULL)
                 mask |= POLLERR | POLLHUP;
-        if (filp->private_data || !list_empty(&pipe->pipe))
+        else if (filp->private_data || !list_empty(&rpci->pipe->pipe))
                 mask |= POLLIN | POLLRDNORM;
+        mutex_unlock(&inode->i_mutex);
         return mask;
 }
 
@@ -543,7 +556,6 @@ init_pipe(struct rpc_pipe *pipe)
         INIT_LIST_HEAD(&pipe->in_downcall);
         INIT_LIST_HEAD(&pipe->pipe);
         pipe->pipelen = 0;
-        init_waitqueue_head(&pipe->waitq);
         INIT_DELAYED_WORK(&pipe->queue_timeout,
                             rpc_timeout_upcall_queue);
         pipe->ops = NULL;
@@ -1165,6 +1177,7 @@ init_once(void *foo)
         inode_init_once(&rpci->vfs_inode);
         rpci->private = NULL;
         rpci->pipe = NULL;
+        init_waitqueue_head(&rpci->waitq);
 }
 
 int register_rpc_pipefs(void)