Extend Single User Mode (SUM) support in sed-opal.

This patch series extends support for TCG Storage Opal SSC Single User
Mode (SUM) in the sed-opal kernel interface. SUM addresses few
shortcomins described in the chapter 2 of the OPAL2 sepecification
extension (see below). It better isolates Admin authority from User
stored data by taking the Lock/Unlock/Enable/Disable privileges from
Admin when managing Locking Ranges configured for SUM.

This permission split necessitates separate ioctl calls for operations
that previously could be performed atomically under a single authority.
The series refactors existing code and introduces new ioctls to support
this model:

- IOC_OPAL_REACTIVATE_LSP: Switch an active OPAL2 device to/from SUM
- IOC_OPAL_LR_SET_START_LEN: Set locking range boundaries only
- IOC_OPAL_ENABLE_DISABLE_LR: Set lock enable states only
- IOC_OPAL_GET_SUM_STATUS: Query SUM configuration status

References:
- TCG Storage Opal SSC Feature Set: Single User Mode specification
- cryptsetup code using the extended sed-opal interface:
  https://gitlab.com/cryptsetup/cryptsetup/-/merge_requests...

Ondrej Kozina (6):
  sed-opal: add IOC_OPAL_REACTIVATE_LSP.
  sed-opal: refactor (split) IOC_OPAL_LR_SETUP internals.
  sed-opal: add IOC_OPAL_LR_SET_START_LEN ioctl.
  sed-opal: add IOC_OPAL_ENABLE_DISABLE_LR.
  sed-opal: increase column attribute type size to 64 bits.
  sed-opal: add IOC_OPAL_GET_SUM_STATUS ioctl.

 block/opal_proto.h            |   4 +
 block/sed-opal.c              | 367 +++++++++++++++++++++++++++++++---
 include/linux/sed-opal.h      |   4 +
 include/uapi/linux/sed-opal.h |  25 +++
 4 files changed, 371 insertions(+), 29 deletions(-)

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2.52.0