[PATCHv5 0/2] loop: enable different logical blocksizes

Hannes Reinecke
2017-02-10T08:43:49Z

Currently the loop driver just simulates 512-byte blocks. When
creating bootable images for virtual machines it might be required
to use a different physical blocksize (eg 4k for S/390 DASD), as
the some bootloaders (like lilo or zipl for S/390) need to know
the physical block addresses of the kernel and initrd.

With this patchset the loop driver will export the logical and
physical blocksize and the current LOOP_SET_STATUS64 ioctl is
extended to set the logical blocksize by re-using the existing
'init' fields, which are currently unused.

As usual, comments and reviews are welcome.

Changes to v1:
- Move LO_FLAGS_BLOCKSIZE definition
- Reshuffle patches
Changes to v2:
- Include reviews from Ming Lei
Changes to v3:
- Include reviews from Christoph
- Merge patches
Changes to v4:
- Add LO_INFO_BLOCKSIZE definition

Hannes Reinecke (2):
loop: Remove unused 'bdev' argument from loop_set_capacity
loop: support 4k physical blocksize

drivers/block/loop.c | 40 +++++++++++++++++++++++++++++++++-------
drivers/block/loop.h | 1 +
include/uapi/linux/loop.h | 3 +++
3 files changed, 37 insertions(+), 7 deletions(-)

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1.8.5.6