All of the Device Mapper “DM” changes have been merged to mainline for the in-development Linux 6.15 kernel.
One of the notable DM changes this cycle is adding support for inline crypto passthrough to dm-stripe, the striped target for Device Mapper to provide RAID-0 like functionality across storage devices. With inline crypto support, it allows making use of hardware encryption of the underlying storage device(s) where capable. A lot of ARM hardware in particular supporting inline encryption hardware and being quite helpful for performance.
The dm-crypt code for Linux 6.15 has switched to using the common CRC32 library. In making use of the common CRC32 library function, it’s easier to take advantage of architecture-specific optimizations and easier to use crc32() than going through the crypto API itself due to higher overhead there.
The DM changes for Linux 6.15 also bring documentation improvements, DM cache now supports shrinking the origin device, and the dm-delay target adds support for zoned storage devices. More details on the many Device Mapper updates for Linux 6.15 via this pull request that was merged overnight to the mainline kernel codebase.
