sunrpc: remove the big kernel lock

The sunrpc cache_ioctl function does not need the big kernel lock
because it uses its own queue_lock already.

rpc_pipe_ioctl apparently should be using i_lock like the other
operations on the pipe file descriptor do.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>

2 files changed, 11 insertions, 30 deletions

diff --git a/net/sunrpc/cache.c b/net/sunrpc/cache.c
index 2b06410e584e..29b11e065015 100644
--- a/net/sunrpc/cache.c
+++ b/net/sunrpc/cache.c
@@ -28,7 +28,6 @@
 #include <linux/workqueue.h>
 #include <linux/mutex.h>
 #include <linux/pagemap.h>
-#include <linux/smp_lock.h>
 #include <asm/ioctls.h>
 #include <linux/sunrpc/types.h>
 #include <linux/sunrpc/cache.h>
@@ -1348,15 +1347,10 @@ static unsigned int cache_poll_procfs(struct file *filp, poll_table *wait)
 static long cache_ioctl_procfs(struct file *filp,
                                unsigned int cmd, unsigned long arg)
 {
-        long ret;
         struct inode *inode = filp->f_path.dentry->d_inode;
         struct cache_detail *cd = PDE(inode)->data;
 
-        lock_kernel();
-        ret = cache_ioctl(inode, filp, cmd, arg, cd);
-        unlock_kernel();
-
-        return ret;
+        return cache_ioctl(inode, filp, cmd, arg, cd);
 }
 
 static int cache_open_procfs(struct inode *inode, struct file *filp)
@@ -1555,13 +1549,8 @@ static long cache_ioctl_pipefs(struct file *filp,
 {
         struct inode *inode = filp->f_dentry->d_inode;
         struct cache_detail *cd = RPC_I(inode)->private;
-        long ret;
 
-        lock_kernel();
-        ret = cache_ioctl(inode, filp, cmd, arg, cd);
-        unlock_kernel();
-
-        return ret;
+        return cache_ioctl(inode, filp, cmd, arg, cd);
 }
 
 static int cache_open_pipefs(struct inode *inode, struct file *filp)
diff --git a/net/sunrpc/rpc_pipe.c b/net/sunrpc/rpc_pipe.c
index 95ccbcf45d3e..1e97d8610291 100644
--- a/net/sunrpc/rpc_pipe.c
+++ b/net/sunrpc/rpc_pipe.c
@@ -27,7 +27,6 @@
 #include <linux/workqueue.h>
 #include <linux/sunrpc/rpc_pipe_fs.h>
 #include <linux/sunrpc/cache.h>
-#include <linux/smp_lock.h>
 
 static struct vfsmount *rpc_mount __read_mostly;
 static int rpc_mount_count;
@@ -309,40 +308,33 @@ rpc_pipe_poll(struct file *filp, struct poll_table_struct *wait)
         return mask;
 }
 
-static int
-rpc_pipe_ioctl_unlocked(struct file *filp, unsigned int cmd, unsigned long arg)
+static long
+rpc_pipe_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 {
-        struct rpc_inode *rpci = RPC_I(filp->f_path.dentry->d_inode);
+        struct inode *inode = filp->f_path.dentry->d_inode;
+        struct rpc_inode *rpci = RPC_I(inode);
         int len;
 
         switch (cmd) {
         case FIONREAD:
-                if (rpci->ops == NULL)
+                spin_lock(&inode->i_lock);
+                if (rpci->ops == NULL) {
+                        spin_unlock(&inode->i_lock);
                         return -EPIPE;
+                }
                 len = rpci->pipelen;
                 if (filp->private_data) {
                         struct rpc_pipe_msg *msg;
                         msg = (struct rpc_pipe_msg *)filp->private_data;
                         len += msg->len - msg->copied;
                 }
+                spin_unlock(&inode->i_lock);
                 return put_user(len, (int __user *)arg);
         default:
                 return -EINVAL;
         }
 }
 
-static long
-rpc_pipe_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
-{
-        long ret;
-
-        lock_kernel();
-        ret = rpc_pipe_ioctl_unlocked(filp, cmd, arg);
-        unlock_kernel();
-
-        return ret;
-}
-
 static const struct file_operations rpc_pipe_fops = {
         .owner          = THIS_MODULE,
         .llseek         = no_llseek,