Btrfs: truncate pages from clone ioctl target range

We need to truncate page cache pages for the clone ioctl target range or else we'll confuse ourselves to no end. If the old data was cached, we used to still see it (until remount). If the page was partially updated we used to get a mix of old and new data. Signed-off-by: Sage Weil <[email protected]> Signed-off-by: Chris Mason <[email protected]>
amrav · Aug 17, 2011 · f81c9cd · f81c9cd
1 parent 0e58885
commit f81c9cd
Showing 1 changed file with 4 additions and 0 deletions.
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
@@ -2244,6 +2244,10 @@ static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd,
 		btrfs_wait_ordered_range(src, off, len);
 	}
 
+	/* truncate page cache pages from target inode range */
+	truncate_inode_pages_range(&inode->i_data, off,
+				   ALIGN(off + len, PAGE_CACHE_SIZE) - 1);
+
 	/* clone data */
 	key.objectid = btrfs_ino(src);
 	key.type = BTRFS_EXTENT_DATA_KEY;