leases: when unlocking, skip locking-related steps

In generic_setlease(), we don't need to allocate a new struct file_lock
or check for readers or writers when called with F_UNLCK.

Signed-off-by: David M. Richter <richterd@citi.umich.edu>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

diff --git a/fs/locks.c b/fs/locks.c
index b9f3a0bed3006810d5e87ddf61db6a55d46d3ce6..da1d0ddb4abdd8040dbbbe1681328b204e63a9c2 100644 (file)
--- a/fs/locks.c
+++ b/fs/locks.c
@@ -1367,18 +1367,20 @@ int generic_setlease(struct file *filp, long arg, struct file_lock **flp)
 
        lease = *flp;
 
-       error = -EAGAIN;
-       if ((arg == F_RDLCK) && (atomic_read(&inode->i_writecount) > 0))
-               goto out;
-       if ((arg == F_WRLCK)
-           && ((atomic_read(&dentry->d_count) > 1)
-               || (atomic_read(&inode->i_count) > 1)))
-               goto out;
+       if (arg != F_UNLCK) {
+               error = -EAGAIN;
+               if ((arg == F_RDLCK) && (atomic_read(&inode->i_writecount) > 0))
+                       goto out;
+               if ((arg == F_WRLCK)
+                   && ((atomic_read(&dentry->d_count) > 1)
+                       || (atomic_read(&inode->i_count) > 1)))
+                       goto out;
 
-       error = -ENOMEM;
-       new_fl = locks_alloc_lock();
-       if (new_fl == NULL)
-               goto out;
+               error = -ENOMEM;
+               new_fl = locks_alloc_lock();
+               if (new_fl == NULL)
+                       goto out;
+       }
 
        /*
         * At this point, we know that if there is an exclusive