/* __unmap_underlying_blocks - just a helper function to unmap set of blocks described by @bh  */
static void __unmap_underlying_blocks(struct inode *inode, struct buffer_head *bh)
/* __unmap_underlying_blocks - just a helper function to unmap set of blocks described by @bh  */
static void __unmap_underlying_blocks(struct inode *inode, struct buffer_head *bh)
{
	struct block_device *bdev = inode->i_sb->s_bdev;
	int blocks, i;
	blocks = bh->b_size >> inode->i_blkbits;
	for (i = 0; i < blocks; i++)
		unmap_underlying_metadata(bdev, bh->b_blocknr + i);
}