System headers should be included with <...>, our own headers with
"...". Offenders tracked down with an ugly, brittle and probably
buggy Perl script. Previous iteration was commit a9c94277f0.
Delete inclusions of "string.h" and "strings.h" instead of fixing them
to <string.h> and <strings.h>, because we always include these via
osdep.h.
Put the cleaned up system header includes first.
While there, separate #include from file comment with exactly one
blank line.
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180201111846.21846-2-armbru@redhat.com>
The default css 0xfe is currently restricted to virtual subchannel
devices. The hope when the decision was made was, that non-virtual
subchannel devices will come around when guest can exploit multiple
channel subsystems. Since the guests generally don't do, the pain
of the partitioned (cssid) namespace outweighs the gain.
Let us remove the corresponding restrictions (virtual devices
can be put only in 0xfe and non-virtual devices in any css except
the 0xfe -- while s390-squash-mcss then remaps everything to cssid 0).
At the same time, change our schema for generating css bus ids to put
both virtual and non-virtual devices into the default css (spilling over
into other css images, if needed). The intention is to deprecate
s390-squash-mcss. With this change devices without a specified devno
won't end up hidden to guests not supporting multiple channel subsystems,
unless this can not be avoided (default css full).
Let us also advertise the changes to the management software (so it can
tell are cssids unrestricted or restricted).
The adverse effect of getting rid of the restriction on migration should
not be too severe. Vfio-ccw devices are not live-migratable yet, and for
virtual devices using the extra freedom would only make sense with the
aforementioned guest support in place.
The auto-generated bus ids are affected by both changes. We hope to not
encounter any auto-generated bus ids in production as Libvirt is always
explicit about the bus id. Since 8ed179c937 ("s390x/css: catch section
mismatch on load", 2017-05-18) the worst that can happen because the same
device ended up having a different bus id is a cleanly failed migration.
I find it hard to reason about the impact of changed auto-generated bus
ids on migration for command line users as I don't know which rules is
such an user supposed to follow.
Another pain-point is down- or upgrade of QEMU for command line users.
The old way and the new way of doing vfio-ccw are mutually incompatible.
Libvirt is only going to support the new way, so for libvirt users, the
possible problems at QEMU downgrade are the following. If a domain
contains virtual devices placed into a css different than 0xfe the domain
will refuse to start with a QEMU not having this patch. Putting devices
into a css different that 0xfe however won't make much sense in the near
future (guest support). Libvirt will refuse to do vfio-ccw with a QEMU
not having this patch. This is business as usual.
Signed-off-by: Halil Pasic <pasic@linux.vnet.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
Message-Id: <20171206144438.28908-2-pasic@linux.vnet.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Simplify the error handling of the SSCH and RSCH handler avoiding
arbitrary and cryptic error codes being used to tell how the instruction
is supposed to end. Let the code detecting the condition tell how it's
to be handled in a less ambiguous way. It's best to handle SSCH and RSCH
in one go as the emulation of the two shares a lot of code.
For passthrough this change isn't pure refactoring, but changes the way
kernel reported EFAULT is handled. After clarifying the kernel interface
we decided that EFAULT shall be mapped to unit exception. Same goes for
unexpected error codes and absence of required ORB flags.
Signed-off-by: Halil Pasic <pasic@linux.vnet.ibm.com>
Message-Id: <20171017140453.51099-4-pasic@linux.vnet.ibm.com>
Tested-by: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
[CH: cosmetic changes]
Reviewed-by: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Implement a basic infrastructure of handling channel I/O instruction
interception for passed through subchannels:
1. Branch the code path of instruction interception handling by
SubChannel type.
2. For a passed-through subchannel, issue the ORB to kernel to do ccw
translation and perform an I/O operation.
3. Assign different condition code based on the I/O result, or
trigger a program check.
Signed-off-by: Xiao Feng Ren <renxiaof@linux.vnet.ibm.com>
Signed-off-by: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
Message-Id: <20170517004813.58227-12-bjsdjshi@linux.vnet.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
In order to support subchannels pass-through, we introduce a s390
subchannel device called "s390-ccw" to hold the real subchannel info.
The s390-ccw devices inherit from the abstract CcwDevice which connect
to the existing virtual-css-bus.
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
Message-Id: <20170517004813.58227-7-bjsdjshi@linux.vnet.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Markus Armbruster
Halil Pasic
Xiao Feng Ren
Dong Jia Shi