ich777/linux_media
1
0
Fork 0
mirror of https://github.com/tbsdtv/linux_media.git synced 2025-07-23 04:33:26 +02:00
Code Issues Packages Projects Releases Wiki Activity

vfio-ccw: Introduce a new schib region

Browse Source 
The schib region can be used by userspace to get the subchannel-
information block (SCHIB) for the passthrough subchannel.
This can be useful to get information such as channel path
information via the SCHIB.PMCW fields.

Signed-off-by: Farhan Ali <alifm@linux.ibm.com>
Signed-off-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20200505122745.53208-5-farman@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
This commit is contained in:
Farhan Ali
2020-05-05 14:27:41 +02:00
committed by Cornelia Huck
parent 600279b526
commit 24c986748b
8 changed files with 140 additions and 4 deletions
Download Patch File Download Diff File Expand all files Collapse all files

18
Documentation/s390/vfio-ccw.rst
View File

@@ -282,6 +282,21 @@ for each access of the region. The following values may occur:
``-EBUSY``
The subchannel was status pending or busy while processing a halt request.
vfio-ccw schib region
---------------------
The vfio-ccw schib region is used to return Subchannel-Information
Block (SCHIB) data to userspace::
struct ccw_schib_region {
#define SCHIB_AREA_SIZE 52
__u8 schib_area[SCHIB_AREA_SIZE];
} __packed;
This region is exposed via region type VFIO_REGION_SUBTYPE_CCW_SCHIB.
Reading this region triggers a STORE SUBCHANNEL to be issued to the
associated hardware.
vfio-ccw operation details
--------------------------
@@ -385,7 +400,8 @@ through DASD/ECKD device online in a guest now and use it as a block
device.
The current code allows the guest to start channel programs via
START SUBCHANNEL, and to issue HALT SUBCHANNEL and CLEAR SUBCHANNEL.
START SUBCHANNEL, and to issue HALT SUBCHANNEL, CLEAR SUBCHANNEL,
and STORE SUBCHANNEL.
Currently all channel programs are prefetched, regardless of the
p-bit setting in the ORB. As a result, self modifying channel