Merge branch 'for-linus' of git://github.com/chrismason/linux

[pandora-kernel.git] / fs / btrfs / ioctl.c

diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 970977a..3351b1b 100644 (file)
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -2220,6 +2220,12 @@ static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd,
            !IS_ALIGNED(destoff, bs))
                goto out_unlock;
 
+       if (destoff > inode->i_size) {
+               ret = btrfs_cont_expand(inode, inode->i_size, destoff);
+               if (ret)
+                       goto out_unlock;
+       }
+
        /* do any pending delalloc/csum calc on src, one way or
           another, and lock file content */
        while (1) {
@@ -2325,14 +2331,21 @@ static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd,
 
                        if (type == BTRFS_FILE_EXTENT_REG ||
                            type == BTRFS_FILE_EXTENT_PREALLOC) {
+                               /*
+                                *    a  | --- range to clone ---|  b
+                                * | ------------- extent ------------- |
+                                */
+
+                               /* substract range b */
+                               if (key.offset + datal > off + len)
+                                       datal = off + len - key.offset;
+
+                               /* substract range a */
                                if (off > key.offset) {
                                        datao += off - key.offset;
                                        datal -= off - key.offset;
                                }
 
-                               if (key.offset + datal > off + len)
-                                       datal = off + len - key.offset;
-
                                ret = btrfs_drop_extents(trans, inode,
                                                         new_key.offset,
                                                         new_key.offset + datal,