Commit 3113a29e authored by Jason J. Herne's avatar Jason J. Herne Committed by Alexander Gordeev
Browse files

docs: Update s390 vfio-ap doc for ap_config sysfs attribute 



A new sysfs attribute, ap_config, for the vfio_ap driver is
documented.

Signed-off-by: default avatar"Jason J. Herne" <jjherne@linux.ibm.com>
Reviewed-by: default avatarTony Krowiak <akrowiak@linux.ibm.com>
Link: https://lore.kernel.org/r/20240415152555.13152-6-jjherne@linux.ibm.com


Signed-off-by: default avatarAlexander Gordeev <agordeev@linux.ibm.com>
parent 8fb456bc

Documentation/arch/s390/vfio-ap.rst

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Original line number Diff line number Diff line
@@ -380,6 +380,36 @@ matrix device. 
    control_domains:

      A read-only file for displaying the control domain numbers assigned to the

      vfio_ap mediated device.

    ap_config:

      A read/write file that, when written to, allows all three of the

      vfio_ap mediated device's ap matrix masks to be replaced in one shot.

      Three masks are given, one for adapters, one for domains, and one for

      control domains. If the given state cannot be set then no changes are

      made to the vfio-ap mediated device.



      The format of the data written to ap_config is as follows:

      {amask},{dmask},{cmask}\n



      \n is a newline character.



      amask, dmask, and cmask are masks identifying which adapters, domains,

      and control domains should be assigned to the mediated device.



      The format of a mask is as follows:

      0xNN..NN



      Where NN..NN is 64 hexadecimal characters representing a 256-bit value.

      The leftmost (highest order) bit represents adapter/domain 0.



      For an example set of masks that represent your mdev's current

      configuration, simply cat ap_config.



      Setting an adapter or domain number greater than the maximum allowed for

      the system will result in an error.



      This attribute is intended to be used by automation. End users would be

      better served using the respective assign/unassign attributes for

      adapters, domains, and control domains.



* functions: