Original messages could evoke reencryption is currently
in progress. That was inaccurate because code only
detected flag marking such device is in transition state
from metadata pov. We should not imply anything about
running processes. That's detected via reencryption locks.
Currently hard memory limit is 1 GiB. Soft limit is
1/4 of system memory.
Note that --hotzone-size cryptsetup parameter can only further
lower hard and soft memory limit on hotzone size and not bypass
it.
If device properly exposes optimal io size, let's align
reencryption hotzone to it. Otherwise device-mapper driver
complaints about misaligned tables and reencryption performance
is not optimal.
Commit 4c73da31 exposed another bug in minimal device size check.
During reencryption initialization wrong data offset value was used
and adjusted as if device was already undergoing reencryption. The
bug fixed by commit 4c73da31 hid this bug.
This is hotfix only and following functions needs more review:
- LUKS2_reencrypt_data_offset
- LUKS2_get_data_offset
- luks2_check_device_size
- LUKS2_get_data_size
- Remove all 'LUKS2_' name prefixes from internal routines
- Make all internal routines prefixed with 'reencrypt_' instead
- Drop few static routines by refactoring
- Rename all variables and routines containing 'pre' prefix to
contain 'hot' prefix instead (when referring to segments
undergoing reencryption)
- Rename all variables and routines containing 'after' prefix to
contain 'post' prefix instead
- Rename all routines prefixed with '_' to 'reencrypt_' instead
If we initialized encryption with data shift and only single
segment the resulting metadata were missing
CRYPT_REENCRYPT_MOVE_FIRST_SEGMENT flag and also segments json section was
invalid.
- make error messages propagated to users more comprehensible
- drop some error messages completely
- replace many error messages with debug logs only
Fixes#458.
LUKS2 and other device types allow stacking of dm devices
underneath public top level device.
The new type identifies clearly those private devices in respective
device stack so that they can be easily removed while removing
top level public device.
Switch LUKS2 reencryption device stack to use SUBDEV type immmediately
for hotzone and overlay devices. Other devices will follow in later
releases.
