From 3113a29e25fe072d6eb0abccd695d7cc72ac9b6f Mon Sep 17 00:00:00 2001 From: "Jason J. Herne" Date: Mon, 15 Apr 2024 11:25:55 -0400 Subject: 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: "Jason J. Herne" Reviewed-by: Tony Krowiak Link: https://lore.kernel.org/r/20240415152555.13152-6-jjherne@linux.ibm.com Signed-off-by: Alexander Gordeev --- Documentation/arch/s390/vfio-ap.rst | 30 ++++++++++++++++++++++++++++++ 1 file changed, 30 insertions(+) diff --git a/Documentation/arch/s390/vfio-ap.rst b/Documentation/arch/s390/vfio-ap.rst index cf8533f2a8b6..ea744cbc8687 100644 --- a/Documentation/arch/s390/vfio-ap.rst +++ b/Documentation/arch/s390/vfio-ap.rst @@ -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: -- cgit v1.2.3