SUNRPC: replace inode lock with pipe lock for RPC PipeFS operations

Currenly, inode i_lock is used to provide concurrent access to SUNPRC PipeFS
pipes. It looks redundant, since now other use of inode is present in most of
these places and thus can be easely replaced, which will allow to remove most
of inode references from PipeFS code. This is a first step towards to removing
PipeFS inode references from kernel code other than PipeFS itself.

Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

1 files changed, 19 insertions, 19 deletions

diff --git a/net/sunrpc/rpc_pipe.c b/net/sunrpc/rpc_pipe.c
index 9a88113..16d9b9a 100644
--- a/net/sunrpc/rpc_pipe.c
+++ b/net/sunrpc/rpc_pipe.c
@@ -83,12 +83,11 @@ rpc_timeout_upcall_queue(struct work_struct *work)
 	LIST_HEAD(free_list);
 	struct rpc_inode *rpci =
 		container_of(work, struct rpc_inode, queue_timeout.work);
-	struct inode *inode = &rpci->vfs_inode;
 	void (*destroy_msg)(struct rpc_pipe_msg *);
 
-	spin_lock(&inode->i_lock);
+	spin_lock(&rpci->lock);
 	if (rpci->ops == NULL) {
-		spin_unlock(&inode->i_lock);
+		spin_unlock(&rpci->lock);
 		return;
 	}
 	destroy_msg = rpci->ops->destroy_msg;
@@ -96,7 +95,7 @@ rpc_timeout_upcall_queue(struct work_struct *work)
 		list_splice_init(&rpci->pipe, &free_list);
 		rpci->pipelen = 0;
 	}
-	spin_unlock(&inode->i_lock);
+	spin_unlock(&rpci->lock);
 	rpc_purge_list(rpci, &free_list, destroy_msg, -ETIMEDOUT);
 }
 
@@ -136,7 +135,7 @@ rpc_queue_upcall(struct inode *inode, struct rpc_pipe_msg *msg)
 	struct rpc_inode *rpci = RPC_I(inode);
 	int res = -EPIPE;
 
-	spin_lock(&inode->i_lock);
+	spin_lock(&rpci->lock);
 	if (rpci->ops == NULL)
 		goto out;
 	if (rpci->nreaders) {
@@ -153,7 +152,7 @@ rpc_queue_upcall(struct inode *inode, struct rpc_pipe_msg *msg)
 		res = 0;
 	}
 out:
-	spin_unlock(&inode->i_lock);
+	spin_unlock(&rpci->lock);
 	wake_up(&rpci->waitq);
 	return res;
 }
@@ -176,14 +175,14 @@ rpc_close_pipes(struct inode *inode)
 	ops = rpci->ops;
 	if (ops != NULL) {
 		LIST_HEAD(free_list);
-		spin_lock(&inode->i_lock);
+		spin_lock(&rpci->lock);
 		need_release = rpci->nreaders != 0 || rpci->nwriters != 0;
 		rpci->nreaders = 0;
 		list_splice_init(&rpci->in_upcall, &free_list);
 		list_splice_init(&rpci->pipe, &free_list);
 		rpci->pipelen = 0;
 		rpci->ops = NULL;
-		spin_unlock(&inode->i_lock);
+		spin_unlock(&rpci->lock);
 		rpc_purge_list(rpci, &free_list, ops->destroy_msg, -EPIPE);
 		rpci->nwriters = 0;
 		if (need_release && ops->release_pipe)
@@ -255,10 +254,10 @@ rpc_pipe_release(struct inode *inode, struct file *filp)
 		goto out;
 	msg = filp->private_data;
 	if (msg != NULL) {
-		spin_lock(&inode->i_lock);
+		spin_lock(&rpci->lock);
 		msg->errno = -EAGAIN;
 		list_del_init(&msg->list);
-		spin_unlock(&inode->i_lock);
+		spin_unlock(&rpci->lock);
 		rpci->ops->destroy_msg(msg);
 	}
 	if (filp->f_mode & FMODE_WRITE)
@@ -267,10 +266,10 @@ rpc_pipe_release(struct inode *inode, struct file *filp)
 		rpci->nreaders --;
 		if (rpci->nreaders == 0) {
 			LIST_HEAD(free_list);
-			spin_lock(&inode->i_lock);
+			spin_lock(&rpci->lock);
 			list_splice_init(&rpci->pipe, &free_list);
 			rpci->pipelen = 0;
-			spin_unlock(&inode->i_lock);
+			spin_unlock(&rpci->lock);
 			rpc_purge_list(rpci, &free_list,
 					rpci->ops->destroy_msg, -EAGAIN);
 		}
@@ -298,7 +297,7 @@ rpc_pipe_read(struct file *filp, char __user *buf, size_t len, loff_t *offset)
 	}
 	msg = filp->private_data;
 	if (msg == NULL) {
-		spin_lock(&inode->i_lock);
+		spin_lock(&rpci->lock);
 		if (!list_empty(&rpci->pipe)) {
 			msg = list_entry(rpci->pipe.next,
 					struct rpc_pipe_msg,
@@ -308,7 +307,7 @@ rpc_pipe_read(struct file *filp, char __user *buf, size_t len, loff_t *offset)
 			filp->private_data = msg;
 			msg->copied = 0;
 		}
-		spin_unlock(&inode->i_lock);
+		spin_unlock(&rpci->lock);
 		if (msg == NULL)
 			goto out_unlock;
 	}
@@ -316,9 +315,9 @@ rpc_pipe_read(struct file *filp, char __user *buf, size_t len, loff_t *offset)
 	res = rpci->ops->upcall(filp, msg, buf, len);
 	if (res < 0 || msg->len == msg->copied) {
 		filp->private_data = NULL;
-		spin_lock(&inode->i_lock);
+		spin_lock(&rpci->lock);
 		list_del_init(&msg->list);
-		spin_unlock(&inode->i_lock);
+		spin_unlock(&rpci->lock);
 		rpci->ops->destroy_msg(msg);
 	}
 out_unlock:
@@ -367,9 +366,9 @@ rpc_pipe_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 
 	switch (cmd) {
 	case FIONREAD:
-		spin_lock(&inode->i_lock);
+		spin_lock(&rpci->lock);
 		if (rpci->ops == NULL) {
-			spin_unlock(&inode->i_lock);
+			spin_unlock(&rpci->lock);
 			return -EPIPE;
 		}
 		len = rpci->pipelen;
@@ -378,7 +377,7 @@ rpc_pipe_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 			msg = filp->private_data;
 			len += msg->len - msg->copied;
 		}
-		spin_unlock(&inode->i_lock);
+		spin_unlock(&rpci->lock);
 		return put_user(len, (int __user *)arg);
 	default:
 		return -EINVAL;
@@ -1153,6 +1152,7 @@ init_once(void *foo)
 	INIT_DELAYED_WORK(&rpci->queue_timeout,
 			    rpc_timeout_upcall_queue);
 	rpci->ops = NULL;
+	spin_lock_init(&rpci->lock);
 }
 
 int register_rpc_pipefs(void)