On 26/06/2020 10:03, Christoph Hellwig wrote:

-	size = bdev->bd_block_size;
-	if (!size)
-		size = 1024;
-

Why is this correct? block_size() only returns 'bdev->bd_block_size' but I cannot 
see where it's made sure bd_block_size is not 0. At least no calls to set_blocksize()