btrfs: abtract out range locking in clone ioctl()

The range locking in btrfs_ioctl_clone is trivially broken out into it's own
function. This reduces the complexity of btrfs_ioctl_clone() by a small bit
and makes that locking code available to future functions in
fs/btrfs/ioctl.c

Signed-off-by: Mark Fasheh <mfasheh@suse.de>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>

1 files changed, 21 insertions, 15 deletions

diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 556b3d5b18da..76c7657a7f53 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -2470,6 +2470,26 @@ out:
         return ret;
 }
 
+static inline void lock_extent_range(struct inode *inode, u64 off, u64 len)
+{
+        /* do any pending delalloc/csum calc on src, one way or
+           another, and lock file content */
+        while (1) {
+                struct btrfs_ordered_extent *ordered;
+                lock_extent(&BTRFS_I(inode)->io_tree, off, off + len - 1);
+                ordered = btrfs_lookup_first_ordered_extent(inode,
+                                                            off + len - 1);
+                if (!ordered &&
+                    !test_range_bit(&BTRFS_I(inode)->io_tree, off,
+                                    off + len - 1, EXTENT_DELALLOC, 0, NULL))
+                        break;
+                unlock_extent(&BTRFS_I(inode)->io_tree, off, off + len - 1);
+                if (ordered)
+                        btrfs_put_ordered_extent(ordered);
+                btrfs_wait_ordered_range(inode, off, len);
+        }
+}
+
 static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd,
                                        u64 off, u64 olen, u64 destoff)
 {
@@ -2598,21 +2618,7 @@ static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd,
         truncate_inode_pages_range(&inode->i_data, destoff,
                                    PAGE_CACHE_ALIGN(destoff + len) - 1);
 
-        /* do any pending delalloc/csum calc on src, one way or
-           another, and lock file content */
-        while (1) {
-                struct btrfs_ordered_extent *ordered;
-                lock_extent(&BTRFS_I(src)->io_tree, off, off + len - 1);
-                ordered = btrfs_lookup_first_ordered_extent(src, off + len - 1);
-                if (!ordered &&
-                    !test_range_bit(&BTRFS_I(src)->io_tree, off, off + len - 1,
-                                    EXTENT_DELALLOC, 0, NULL))
-                        break;
-                unlock_extent(&BTRFS_I(src)->io_tree, off, off + len - 1);
-                if (ordered)
-                        btrfs_put_ordered_extent(ordered);
-                btrfs_wait_ordered_range(src, off, len);
-        }
+        lock_extent_range(src, off, len);
 
         /* clone data */
         key.objectid = btrfs_ino(src);