SUNRPC: split SUNPRC PipeFS pipe data and inode creation

Generally, pipe data is used only for pipes, and thus allocating space for it
on every RPC inode allocation is redundant. This patch splits private SUNRPC
PipeFS pipe data and inode, makes pipe data allocated only for pipe inodes.
This patch is also is a next step towards to 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>

include/linux/sunrpc/rpc_pipe_fs.h

@@ -21,9 +21,7 @@ struct rpc_pipe_ops {
 	void (*destroy_msg)(struct rpc_pipe_msg *);
 };
 
-struct rpc_inode {
-	struct inode vfs_inode;
-	void *private;
+struct rpc_pipe {
 	struct list_head pipe;
 	struct list_head in_upcall;
 	struct list_head in_downcall;
@@ -38,6 +36,12 @@ struct rpc_inode {
 	spinlock_t lock;
 };
 
+struct rpc_inode {
+	struct inode vfs_inode;
+	void *private;
+	struct rpc_pipe *pipe;
+};
+
 static inline struct rpc_inode *
 RPC_I(struct inode *inode)
 {

net/sunrpc/auth_gss/auth_gss.c

@@ -112,7 +112,7 @@ gss_put_ctx(struct gss_cl_ctx *ctx)
 /* gss_cred_set_ctx:
  * called by gss_upcall_callback and gss_create_upcall in order
  * to set the gss context. The actual exchange of an old context
- * and a new one is protected by the rpci->lock.
+ * and a new one is protected by the rpci->pipe->lock.
  */
 static void
 gss_cred_set_ctx(struct rpc_cred *cred, struct gss_cl_ctx *ctx)
@@ -297,7 +297,7 @@ static struct gss_upcall_msg *
 __gss_find_upcall(struct rpc_inode *rpci, uid_t uid)
 {
 	struct gss_upcall_msg *pos;
-	list_for_each_entry(pos, &rpci->in_downcall, list) {
+	list_for_each_entry(pos, &rpci->pipe->in_downcall, list) {
 		if (pos->uid != uid)
 			continue;
 		atomic_inc(&pos->count);
@@ -318,14 +318,14 @@ gss_add_msg(struct gss_upcall_msg *gss_msg)
 	struct rpc_inode *rpci = gss_msg->inode;
 	struct gss_upcall_msg *old;
 
-	spin_lock(&rpci->lock);
+	spin_lock(&rpci->pipe->lock);
 	old = __gss_find_upcall(rpci, gss_msg->uid);
 	if (old == NULL) {
 		atomic_inc(&gss_msg->count);
-		list_add(&gss_msg->list, &rpci->in_downcall);
+		list_add(&gss_msg->list, &rpci->pipe->in_downcall);
 	} else
 		gss_msg = old;
-	spin_unlock(&rpci->lock);
+	spin_unlock(&rpci->pipe->lock);
 	return gss_msg;
 }
 
@@ -345,10 +345,10 @@ gss_unhash_msg(struct gss_upcall_msg *gss_msg)
 
 	if (list_empty(&gss_msg->list))
 		return;
-	spin_lock(&rpci->lock);
+	spin_lock(&rpci->pipe->lock);
 	if (!list_empty(&gss_msg->list))
 		__gss_unhash_msg(gss_msg);
-	spin_unlock(&rpci->lock);
+	spin_unlock(&rpci->pipe->lock);
 }
 
 static void
@@ -377,9 +377,9 @@ gss_upcall_callback(struct rpc_task *task)
 	struct gss_upcall_msg *gss_msg = gss_cred->gc_upcall;
 	struct rpc_inode *rpci = gss_msg->inode;
 
-	spin_lock(&rpci->lock);
+	spin_lock(&rpci->pipe->lock);
 	gss_handle_downcall_result(gss_cred, gss_msg);
-	spin_unlock(&rpci->lock);
+	spin_unlock(&rpci->pipe->lock);
 	task->tk_status = gss_msg->msg.errno;
 	gss_release_msg(gss_msg);
 }
@@ -524,7 +524,7 @@ gss_refresh_upcall(struct rpc_task *task)
 		goto out;
 	}
 	rpci = gss_msg->inode;
-	spin_lock(&rpci->lock);
+	spin_lock(&rpci->pipe->lock);
 	if (gss_cred->gc_upcall != NULL)
 		rpc_sleep_on(&gss_cred->gc_upcall->rpc_waitqueue, task, NULL);
 	else if (gss_msg->ctx == NULL && gss_msg->msg.errno >= 0) {
@@ -537,7 +537,7 @@ gss_refresh_upcall(struct rpc_task *task)
 		gss_handle_downcall_result(gss_cred, gss_msg);
 		err = gss_msg->msg.errno;
 	}
-	spin_unlock(&rpci->lock);
+	spin_unlock(&rpci->pipe->lock);
 	gss_release_msg(gss_msg);
 out:
 	dprintk("RPC: %5u gss_refresh_upcall for uid %u result %d\n",
@@ -575,11 +575,11 @@ gss_create_upcall(struct gss_auth *gss_auth, struct gss_cred *gss_cred)
 	rpci = gss_msg->inode;
 	for (;;) {
 		prepare_to_wait(&gss_msg->waitqueue, &wait, TASK_KILLABLE);
-		spin_lock(&rpci->lock);
+		spin_lock(&rpci->pipe->lock);
 		if (gss_msg->ctx != NULL || gss_msg->msg.errno < 0) {
 			break;
 		}
-		spin_unlock(&rpci->lock);
+		spin_unlock(&rpci->pipe->lock);
 		if (fatal_signal_pending(current)) {
 			err = -ERESTARTSYS;
 			goto out_intr;
@@ -590,7 +590,7 @@ gss_create_upcall(struct gss_auth *gss_auth, struct gss_cred *gss_cred)
 		gss_cred_set_ctx(cred, gss_msg->ctx);
 	else
 		err = gss_msg->msg.errno;
-	spin_unlock(&rpci->lock);
+	spin_unlock(&rpci->pipe->lock);
 out_intr:
 	finish_wait(&gss_msg->waitqueue, &wait);
 	gss_release_msg(gss_msg);
@@ -638,14 +638,14 @@ gss_pipe_downcall(struct file *filp, const char __user *src, size_t mlen)
 
 	err = -ENOENT;
 	/* Find a matching upcall */
-	spin_lock(&rpci->lock);
+	spin_lock(&rpci->pipe->lock);
 	gss_msg = __gss_find_upcall(rpci, uid);
 	if (gss_msg == NULL) {
-		spin_unlock(&rpci->lock);
+		spin_unlock(&rpci->pipe->lock);
 		goto err_put_ctx;
 	}
 	list_del_init(&gss_msg->list);
-	spin_unlock(&rpci->lock);
+	spin_unlock(&rpci->pipe->lock);
 
 	p = gss_fill_context(p, end, ctx, gss_msg->auth->mech);
 	if (IS_ERR(p)) {
@@ -673,9 +673,9 @@ gss_pipe_downcall(struct file *filp, const char __user *src, size_t mlen)
 	err = mlen;
 
 err_release_msg:
-	spin_lock(&rpci->lock);
+	spin_lock(&rpci->pipe->lock);
 	__gss_unhash_msg(gss_msg);
-	spin_unlock(&rpci->lock);
+	spin_unlock(&rpci->pipe->lock);
 	gss_release_msg(gss_msg);
 err_put_ctx:
 	gss_put_ctx(ctx);
@@ -725,19 +725,19 @@ gss_pipe_release(struct inode *inode)
 	struct gss_upcall_msg *gss_msg;
 
 restart:
-	spin_lock(&rpci->lock);
-	list_for_each_entry(gss_msg, &rpci->in_downcall, list) {
+	spin_lock(&rpci->pipe->lock);
+	list_for_each_entry(gss_msg, &rpci->pipe->in_downcall, list) {
 
 		if (!list_empty(&gss_msg->msg.list))
 			continue;
 		gss_msg->msg.errno = -EPIPE;
 		atomic_inc(&gss_msg->count);
 		__gss_unhash_msg(gss_msg);
-		spin_unlock(&rpci->lock);
+		spin_unlock(&rpci->pipe->lock);
 		gss_release_msg(gss_msg);
 		goto restart;
 	}
-	spin_unlock(&rpci->lock);
+	spin_unlock(&rpci->pipe->lock);
 
 	put_pipe_version();
 }