[PATCH 4/4] block: add IOC_PR_READ_RESERVATION ioctl

[Hannes Reinecke]

On 11/26/25 17:36, Stefan Hajnoczi wrote:
> Add a Persistent Reservations ioctl to read the current reservation.
> This calls the pr_ops->read_reservation() function that was previously
> added in commit c787f1baa503 ("block: Add PR callouts for read keys and
> reservation") but was only used by the in-kernel SCSI target so far.
> 
> The IOC_PR_READ_RESERVATION ioctl is necessary so that userspace
> applications that rely on Persistent Reservations ioctls have a way of
> inspecting the current state. Cluster managers and validation tests need
> this functionality.
> 
> Signed-off-by: Stefan Hajnoczi <stefanha at redhat.com>
> ---
>   include/uapi/linux/pr.h |  7 +++++++
>   block/ioctl.c           | 28 ++++++++++++++++++++++++++++
>   2 files changed, 35 insertions(+)
> 
Reviewed-by: Hannes Reinecke <hare at suse.de>

Cheers,

Hannes
-- 
Dr. Hannes Reinecke                  Kernel Storage Architect
hare at suse.de                                +49 911 74053 688
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