loop: support 4k physical blocksize
authorHannes Reinecke <hare@suse.de>
Thu, 8 Jun 2017 11:46:45 +0000 (13:46 +0200)
committerJens Axboe <axboe@fb.com>
Thu, 8 Jun 2017 14:40:00 +0000 (08:40 -0600)
commitf2c6df7dbf9a60e1cd9941f9fb376d4d9ad1e8dd
tree79a9c0d9627fa253955532d6925e9606e1643f72
parent51001b7da364a24ed2464f3c22179efdc6b3a960
loop: support 4k physical blocksize

When generating bootable VM images certain systems (most notably
s390x) require devices with 4k blocksize. This patch implements
a new flag 'LO_FLAGS_BLOCKSIZE' which will set the physical
blocksize to that of the underlying device, and allow to change
the logical blocksize for up to the physical blocksize.

Signed-off-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
drivers/block/loop.c
drivers/block/loop.h
include/uapi/linux/loop.h