Re: [PATCH v7] block: sed-opal: Add ioctl to return device status

[Jens Axboe <axboe@kernel.dk>]

On 8/19/22 4:45 AM, Luca Boccassi wrote:
> On Tue, 16 Aug 2022 at 15:07, <luca.boccassi@gmail.com> wrote:
>>
>> From: "dougmill@linux.vnet.ibm.com" <dougmill@linux.vnet.ibm.com>
>>
>> Provide a mechanism to retrieve basic status information about
>> the device, including the "supported" flag indicating whether
>> SED-OPAL is supported. The information returned is from the various
>> feature descriptors received during the discovery0 step, and so
>> this ioctl does nothing more than perform the discovery0 step
>> and then save the information received. See "struct opal_status"
>> and OPAL_FL_* bits for the status information currently returned.
>>
>> This is necessary to be able to check whether a device is OPAL
>> enabled, set up, locked or unlocked from userspace programs
>> like systemd-cryptsetup and libcryptsetup. Right now we just
>> have to assume the user 'knows' or blindly attempt setup/lock/unlock
>> operations.
>>
>> Signed-off-by: Douglas Miller <dougmill@linux.vnet.ibm.com>
>> Tested-by: Luca Boccassi <bluca@debian.org>
>> Reviewed-by: Scott Bauer <sbauer@plzdonthack.me>
>> Acked-by: Christian Brauner (Microsoft) <brauner@kernel.org>
>> ---
>> v2: https://patchwork.kernel.org/project/linux-block/patch/612795b5.tj7FMS9wzchsMzrK%25dougmill@linux.vnet.ibm.com/
>> v3: resend on request, after rebasing and testing on my machine
>>     https://patchwork.kernel.org/project/linux-block/patch/20220125215248.6489-1-luca.boccassi@gmail.com/
>> v4: it's been more than 7 months and no alternative approach has appeared.
>>     we really need to be able to identify and query the status of a sed-opal
>>     device, so rebased and resending.
>> v5: as requested by reviewer, add __32 reserved to the UAPI ioctl struct to align to 64
>>     bits and to reserve space for future expansion
>> v6: as requested by reviewer, update commit message with use case
>> v7: as requested by reviewer, remove braces around single-line 'if'
>>     added received acked-by/reviewed-by tags
>>
>>  block/opal_proto.h            |  5 ++
>>  block/sed-opal.c              | 89 ++++++++++++++++++++++++++++++-----
>>  include/linux/sed-opal.h      |  1 +
>>  include/uapi/linux/sed-opal.h | 13 +++++
>>  4 files changed, 96 insertions(+), 12 deletions(-)
> 
> Hello Jens,
> 
> Is there anything else I can do for this patch? I've got two acks. We
> really need this interface in place to start working on supporting
> sed/opal in cryptsetup.

It's just bad timing, since we just left the merge window. I'll queue it
up when I open up the block bits for 6.1.

-- 
Jens Axboe