blk_queue_physical_block_size(9) centos man page | unix.com

BLK_QUEUE_PHYSICAL_B(9) 					   Block Devices					   BLK_QUEUE_PHYSICAL_B(9)

NAME
       blk_queue_physical_block_size - set physical block size for the queue

SYNOPSIS
       void blk_queue_physical_block_size(struct request_queue * q, unsigned int size);

ARGUMENTS
       q
	   the request queue for the device

       size
	   the physical block size, in bytes

DESCRIPTION
       This should be set to the lowest possible sector size that the hardware can operate on without reverting to read-modify-write operations.

COPYRIGHT
Kernel Hackers Manual 3.10					     June 2014						   BLK_QUEUE_PHYSICAL_B(9)