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2020-06-03vfio-ccw: Introduce a new CRW regionFarhan Ali1-0/+20
This region provides a mechanism to pass a Channel Report Word that affect vfio-ccw devices, and needs to be passed to the guest for its awareness and/or processing. The base driver (see crw_collect_info()) provides space for two CRWs, as a subchannel event may have two CRWs chained together (one for the ssid, one for the subchannel). As vfio-ccw will deal with everything at the subchannel level, provide space for a single CRW to be transferred in one shot. 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: <20200505122745.53208-7-farman@linux.ibm.com> [CH: added padding to ccw_crw_region] Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2020-06-02vfio-ccw: Introduce a new schib regionFarhan Ali1-1/+17
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>
2020-06-02vfio-ccw: document possible errorsCornelia Huck1-2/+54
Interacting with the I/O and the async regions can yield a number of errors, which had been undocumented so far. These are part of the api, so remedy that. Signed-off-by: Cornelia Huck <cohuck@redhat.com> Reviewed-by: Eric Farman <farman@linux.ibm.com> Message-Id: <20200407111605.1795-1-cohuck@redhat.com>
2020-06-02vfio-ccw: Enable transparent CCW IPL from DASDJared Rossi1-0/+6
Remove the explicit prefetch check when using vfio-ccw devices. This check does not trigger in practice as all Linux channel programs are intended to use prefetch. It is expected that all ORBs issued by Linux will request prefetch. Although non-prefetching ORBs are not rejected, they will prefetch nonetheless. A warning is issued up to once per 5 seconds when a forced prefetch occurs. A non-prefetch ORB does not necessarily result in an error, however frequent encounters with non-prefetch ORBs indicate that channel programs are being executed in a way that is inconsistent with what the guest is requesting. While there is currently no known case of an error caused by forced prefetch, it is possible in theory that forced prefetch could result in an error if applied to a channel program that is dependent on non-prefetch. Signed-off-by: Jared Rossi <jrossi@linux.ibm.com> Reviewed-by: Eric Farman <farman@linux.ibm.com> Message-Id: <20200506212440.31323-2-jrossi@linux.ibm.com> Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-07-23Merge tag 'vfio-ccw-20190717-2' of ↵Heiko Carstens1-3/+28
https://git.kernel.org/pub/scm/linux/kernel/git/kvms390/vfio-ccw into fixes Fixes in vfio-ccw for older and newer issues.
2019-07-17Documentation: fix vfio-ccw docCornelia Huck1-8/+8
*Really* mark the literal block as such. Fixes: 127e62174041 ("vfio-ccw: Update documentation for csch/hsch") Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-07-15docs: driver-api: add a series of orphaned documentsMauro Carvalho Chehab1-3/+3
There are lots of documents under Documentation/*.txt and a few other orphan documents elsehwere that belong to the driver-API book. Move them to their right place. Reviewed-by: Cornelia Huck <cohuck@redhat.com> # vfio-related parts Acked-by: Logan Gunthorpe <logang@deltatee.com> # switchtec Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
2019-07-15vfio-ccw: Update documentation for csch/hschFarhan Ali1-3/+28
We now support CLEAR SUBCHANNEL and HALT SUBCHANNEL via ccw_cmd_region. Fixes: d5afd5d135c8 ("vfio-ccw: add handling for async channel instructions") Signed-off-by: Farhan Ali <alifm@linux.ibm.com> Message-Id: <7d977612c3f3152ffb950d77ae11b4b25c1e20c4.1562854091.git.alifm@linux.ibm.com> [CH: properly mark region as literal block] Reviewed-by: Cornelia Huck <cohuck@redhat.com> Reviewed-by: Eric Farman <farman@linux.ibm.com> Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-06-11docs: s390: convert docs to ReST and rename to *.rstMauro Carvalho Chehab1-0/+326
Convert all text files with s390 documentation to ReST format. Tried to preserve as much as possible the original document format. Still, some of the files required some work in order for it to be visible on both plain text and after converted to html. The conversion is actually: - add blank lines and identation in order to identify paragraphs; - fix tables markups; - add some lists markups; - mark literal blocks; - adjust title markups. At its new index.rst, let's add a :orphan: while this is not linked to the main index.rst file, in order to avoid build warnings. Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>