Re: [PATCH v2 5/5] s390: doc: Update doc

From: Anthony Krowiak
Date: Mon Mar 11 2024 - 14:21:10 EST



On 3/6/24 9:08 AM, Jason J. Herne wrote:
fix me

Signed-off-by: Jason J. Herne <jjherne@xxxxxxxxxxxxx>
---
Documentation/arch/s390/vfio-ap.rst | 27 +++++++++++++++++++++++++++
1 file changed, 27 insertions(+)

diff --git a/Documentation/arch/s390/vfio-ap.rst b/Documentation/arch/s390/vfio-ap.rst
index 929ee1c1c940..af5ef60355a2 100644
--- a/Documentation/arch/s390/vfio-ap.rst
+++ b/Documentation/arch/s390/vfio-ap.rst
@@ -380,6 +380,33 @@ 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 the entire vfio_ap mediated
+ device's ap configuration 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.


Same comment I made in patch 4/5:

I won't reject giving an r-b for the above, but could be more informative; maybe more along the lines of how this is described in all documentation:


Where NN..NN is 64 hexadecimal characters comprising a bitmap containing 256 bits. Each bit, from left

to right, corresponds to a number from 0 to 255. If a bit is set, the

corresponding adapter, domain or control domain is assigned to the vfio_ap mdev.

You could also mention that setting an adapter or domain number greater than the maximum allowed for

for the system will result in an error.


+
+ For an example set of masks that represent your mdev's current
+ configuration, simply cat ap_config.
+
+ 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: