Add decription of the allow_discard option added in commit
84597a44a9.
Signed-off-by: Milan Broz <gmazyland@gmail.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
ARC4 is no longer considered secure, so it shouldn't be used, even as
just an example.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Metadata runs are supposed to be aligned on 4k boundary (so that they work
efficiently with disks with 4k sectors). However, there was a programming
bug that makes them aligned on 128k boundary instead. The unused space is
wasted.
Fix this bug by providing a proper 4k alignment. In order to keep
existing volumes working, we introduce a new flag SB_FLAG_FIXED_PADDING
- when the flag is clear, we calculate the padding the old way. In order
to make sure that the old version cannot mount the volume created by the
new version, we increase superblock version to 4.
Also in order to not break with old integritysetup, we fix alignment
only if the parameter "fix_padding" is present when formatting the
device.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
The DM support describes lots of aspects related to mapped
disk partitions from the userspace PoV.
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Randy Dunlap