btrfs: use GFP_KERNEL in btrfs_defrag_file

We can safely use GFP_KERNEL, the function is called from two contexts:

- ioctl handler, called directly, no locks taken
- cleaner thread, running all queued defrag work, outside of any locks

Signed-off-by: David Sterba <dsterba@suse.com>

fs/btrfs/ioctl.c

@@ -1277,7 +1277,7 @@ int btrfs_defrag_file(struct inode *inode, struct file *file,
 	 * context
 	 */
 	if (!file) {
-		ra = kzalloc(sizeof(*ra), GFP_NOFS);
+		ra = kzalloc(sizeof(*ra), GFP_KERNEL);
 		if (!ra)
 			return -ENOMEM;
 		file_ra_state_init(ra, inode->i_mapping);
@@ -1285,8 +1285,7 @@ int btrfs_defrag_file(struct inode *inode, struct file *file,
 		ra = &file->f_ra;
 	}
 
-	pages = kmalloc_array(max_cluster, sizeof(struct page *),
-			GFP_NOFS);
+	pages = kmalloc_array(max_cluster, sizeof(struct page *), GFP_KERNEL);
 	if (!pages) {
 		ret = -ENOMEM;
 		goto out_ra;