A pwrite() call returns the number of bytes written (or -1 on error),
and vfio-ccw compares this number with the size of the region to
determine if an error had occurred or not.
If they are not equal, this is a failure and the errno is used to
determine exactly how things failed. An errno of zero is possible
(though unlikely) in this situation and would be translated to a
successful operation.
If they ARE equal, the ret_code field is read from the region to
determine how to proceed. While the kernel sets the ret_code field
as necessary, the region and thus this field is not "written back"
to the user. So the value can only be what it was initialized to,
which is zero.
So, let's convert an unexpected length with errno of zero to a
return code of -EFAULT, and explicitly set an expected length to
a return code of zero. This will be a little safer and clearer.
Suggested-by: Matthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: Eric Farman <farman@linux.ibm.com>
Message-Id: <20210303160739.2179378-1-farman@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Now that the vfio-ccw code has a notifier interface to request that
a device be unplugged, let's wire that together.
Signed-off-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20210104202057.48048-4-farman@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
vfio_get_dev_region_info() unconditionally allocates memory
for a passed-in vfio_region_info structure (and does not re-use
an already allocated structure). Therefore, we have to free
the structure we pass to that function in vfio_ccw_get_region()
for every region we successfully obtained information for.
Fixes: 8fadea24de ("vfio-ccw: support async command subregion")
Fixes: 46ea3841ed ("vfio-ccw: Add support for the schib region")
Fixes: f030532f2a ("vfio-ccw: Add support for the CRW region and IRQ")
Reported-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20200928101701.13540-1-cohuck@redhat.com>
VFIO is (except devices without a physical IOMMU or some mediated devices)
incompatible with discarding of RAM. The kernel will pin basically all VM
memory. Let's convert to ram_block_discard_disable(), which can now
fail, in contrast to qemu_balloon_inhibit().
Leave "x-balloon-allowed" named as it is for now.
Reviewed-by: Tony Krowiak <akrowiak@linux.ibm.com>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Cc: Cornelia Huck <cohuck@redhat.com>
Cc: Alex Williamson <alex.williamson@redhat.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Tony Krowiak <akrowiak@linux.ibm.com>
Cc: Halil Pasic <pasic@linux.ibm.com>
Cc: Pierre Morel <pmorel@linux.ibm.com>
Cc: Eric Farman <farman@linux.ibm.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20200626072248.78761-4-david@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
The crw region can be used to obtain information about
Channel Report Words (CRW) from vfio-ccw driver.
Currently only channel-path related CRWs are passed to
QEMU from vfio-ccw driver.
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: <20200505125757.98209-7-farman@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Make it easier to add new ones in the future.
Signed-off-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20200505125757.98209-5-farman@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
The schib region can be used to obtain the latest SCHIB from the host
passthrough subchannel. Since the guest SCHIB is virtualized,
we currently only update the path related information so that the
guest is aware of any path related changes when it issues the
'stsch' instruction.
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: <20200505125757.98209-4-farman@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
While we're at it, add a g_free() for the async_cmd_region that
is the last thing currently created. g_free() knows how to handle
NULL pointers, so this makes it easier to remember what cleanups
need to be performed when new regions are added.
Signed-off-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20200505125757.98209-3-farman@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
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.
Newer Linux kernel versions do not require to force the PFCH flag with
vfio-ccw devices anymore.
Signed-off-by: Jared Rossi <jrossi@linux.ibm.com>
Reviewed-by: Eric Farman <farman@linux.ibm.com>
Message-Id: <20200512181535.18630-2-jrossi@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Devices may have component devices and buses.
Device realization may fail. Realization is recursive: a device's
realize() method realizes its components, and device_set_realized()
realizes its buses (which should in turn realize the devices on that
bus, except bus_set_realized() doesn't implement that, yet).
When realization of a component or bus fails, we need to roll back:
unrealize everything we realized so far. If any of these unrealizes
failed, the device would be left in an inconsistent state. Must not
happen.
device_set_realized() lets it happen: it ignores errors in the roll
back code starting at label child_realize_fail.
Since realization is recursive, unrealization must be recursive, too.
But how could a partly failed unrealize be rolled back? We'd have to
re-realize, which can fail. This design is fundamentally broken.
device_set_realized() does not roll back at all. Instead, it keeps
unrealizing, ignoring further errors.
It can screw up even for a device with no buses: if the lone
dc->unrealize() fails, it still unregisters vmstate, and calls
listeners' unrealize() callback.
bus_set_realized() does not roll back either. Instead, it stops
unrealizing.
Fortunately, no unrealize method can fail, as we'll see below.
To fix the design error, drop parameter @errp from all the unrealize
methods.
Any unrealize method that uses @errp now needs an update. This leads
us to unrealize() methods that can fail. Merely passing it to another
unrealize method cannot cause failure, though. Here are the ones that
do other things with @errp:
* virtio_serial_device_unrealize()
Fails when qbus_set_hotplug_handler() fails, but still does all the
other work. On failure, the device would stay realized with its
resources completely gone. Oops. Can't happen, because
qbus_set_hotplug_handler() can't actually fail here. Pass
&error_abort to qbus_set_hotplug_handler() instead.
* hw/ppc/spapr_drc.c's unrealize()
Fails when object_property_del() fails, but all the other work is
already done. On failure, the device would stay realized with its
vmstate registration gone. Oops. Can't happen, because
object_property_del() can't actually fail here. Pass &error_abort
to object_property_del() instead.
* spapr_phb_unrealize()
Fails and bails out when remove_drcs() fails, but other work is
already done. On failure, the device would stay realized with some
of its resources gone. Oops. remove_drcs() fails only when
chassis_from_bus()'s object_property_get_uint() fails, and it can't
here. Pass &error_abort to remove_drcs() instead.
Therefore, no unrealize method can fail before this patch.
device_set_realized()'s recursive unrealization via bus uses
object_property_set_bool(). Can't drop @errp there, so pass
&error_abort.
We similarly unrealize with object_property_set_bool() elsewhere,
always ignoring errors. Pass &error_abort instead.
Several unrealize methods no longer handle errors from other unrealize
methods: virtio_9p_device_unrealize(),
virtio_input_device_unrealize(), scsi_qdev_unrealize(), ...
Much of the deleted error handling looks wrong anyway.
One unrealize methods no longer ignore such errors:
usb_ehci_pci_exit().
Several realize methods no longer ignore errors when rolling back:
v9fs_device_realize_common(), pci_qdev_unrealize(),
spapr_phb_realize(), usb_qdev_realize(), vfio_ccw_realize(),
virtio_device_realize().
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200505152926.18877-17-armbru@redhat.com>
In my "build everything" tree, changing hw/qdev-properties.h triggers
a recompile of some 2700 out of 6600 objects (not counting tests and
objects that don't depend on qemu/osdep.h).
Many places including hw/qdev-properties.h (directly or via hw/qdev.h)
actually need only hw/qdev-core.h. Include hw/qdev-core.h there
instead.
hw/qdev.h is actually pointless: all it does is include hw/qdev-core.h
and hw/qdev-properties.h, which in turn includes hw/qdev-core.h.
Replace the remaining uses of hw/qdev.h by hw/qdev-properties.h.
While there, delete a few superfluous inclusions of hw/qdev-core.h.
Touching hw/qdev-properties.h now recompiles some 1200 objects.
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Daniel P. Berrangé" <berrange@redhat.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Message-Id: <20190812052359.30071-22-armbru@redhat.com>
In my "build everything" tree, changing qemu/main-loop.h triggers a
recompile of some 5600 out of 6600 objects (not counting tests and
objects that don't depend on qemu/osdep.h). It includes block/aio.h,
which in turn includes qemu/event_notifier.h, qemu/notify.h,
qemu/processor.h, qemu/qsp.h, qemu/queue.h, qemu/thread-posix.h,
qemu/thread.h, qemu/timer.h, and a few more.
Include qemu/main-loop.h only where it's needed. Touching it now
recompiles only some 1700 objects. For block/aio.h and
qemu/event_notifier.h, these numbers drop from 5600 to 2800. For the
others, they shrink only slightly.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20190812052359.30071-21-armbru@redhat.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Coverity doesn't like that most callers of vfio_set_irq_signaling() check
the return value and doesn't understand the equivalence of testing the
error pointer instead. Test the return value consistently.
Reported-by: Coverity (CID 1402783)
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Message-Id: <156209642116.14915.9598593247782519613.stgit@gimli.home>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
A vfio-ccw device may provide an async command subregion for
issuing halt/clear subchannel requests. If it is present, use
it for sending halt/clear request to the device; if not, fall
back to emulation (as done today).
Reviewed-by: Farhan Ali <alifm@linux.ibm.com>
Message-Id: <20190613092542.2834-1-cohuck@redhat.com>
Reviewed-by: Eric Farman <farman@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Use the new helper.
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Eric Farman <farman@linux.ibm.com>
Message-Id: <20190617101036.4087-1-cohuck@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
It's recommended that VMStateDescription names are decoupled from QOM
type names as the latter may freely change without consideration of
migration compatibility.
Link: https://lists.gnu.org/archive/html/qemu-devel/2018-10/msg02175.html
CC: qemu-trivial@nongnu.org
Signed-off-by: Li Qiang <liq3ea@163.com>
Message-Id: <20190521151543.92274-3-liq3ea@163.com>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Add bootindex property and iplb data for vfio-ccw devices. This allows us to
forward boot information into the bios for vfio-ccw devices.
Refactor s390_get_ccw_device() to return device type. This prevents us from
having to use messy casting logic in several places.
Signed-off-by: Jason J. Herne <jjherne@linux.ibm.com>
Acked-by: Halil Pasic <pasic@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-Id: <1554388475-18329-2-git-send-email-jjherne@linux.ibm.com>
[thuth: fixed "typedef struct VFIOCCWDevice" build failure with clang]
Signed-off-by: Thomas Huth <thuth@redhat.com>
The GCC 9 compiler complains about many places in s390 code
that take the address of members of the 'struct SCHIB' which
is marked packed:
hw/vfio/ccw.c: In function ‘vfio_ccw_io_notifier_handler’:
hw/vfio/ccw.c:133:15: warning: taking address of packed member of ‘struct SCHIB’ may result in an unaligned pointer value \
[-Waddress-of-packed-member]
133 | SCSW *s = &sch->curr_status.scsw;
| ^~~~~~~~~~~~~~~~~~~~~~
hw/vfio/ccw.c:134:15: warning: taking address of packed member of ‘struct SCHIB’ may result in an unaligned pointer value \
[-Waddress-of-packed-member]
134 | PMCW *p = &sch->curr_status.pmcw;
| ^~~~~~~~~~~~~~~~~~~~~~
...snip many more...
Almost all of these are just done for convenience to avoid
typing out long variable/field names when referencing struct
members. We can get most of this convenience by taking the
address of the 'struct SCHIB' instead, avoiding triggering
the compiler warnings.
In a couple of places we copy via a local variable which is
a technique already applied elsewhere in s390 code for this
problem.
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20190329111104.17223-12-berrange@redhat.com>
Reviewed-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Halil Pasic <pasic@linux.ibm.com>
Reviewed-by: Farhan Ali <alifm@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Add two functions to print an error/warning report once depending
on a passed-in condition variable and flip it if printed. This is
useful if you want to print a message not once-globally, but e.g.
once-per-device.
Inspired by warn_once() in hw/vfio/ccw.c, which has been replaced
with warn_report_once_cond().
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20180830145902.27376-2-cohuck@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
[Function comments reworded]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
If a vfio assigned device makes use of a physical IOMMU, then memory
ballooning is necessarily inhibited due to the page pinning, lack of
page level granularity at the IOMMU, and sufficient notifiers to both
remove the page on balloon inflation and add it back on deflation.
However, not all devices are backed by a physical IOMMU. In the case
of mediated devices, if a vendor driver is well synchronized with the
guest driver, such that only pages actively used by the guest driver
are pinned by the host mdev vendor driver, then there should be no
overlap between pages available for the balloon driver and pages
actively in use by the device. Under these conditions, ballooning
should be safe.
vfio-ccw devices are always mediated devices and always operate under
the constraints above. Therefore we can consider all vfio-ccw devices
as balloon compatible.
The situation is far from straightforward with vfio-pci. These
devices can be physical devices with physical IOMMU backing or
mediated devices where it is unknown whether a physical IOMMU is in
use or whether the vendor driver is well synchronized to the working
set of the guest driver. The safest approach is therefore to assume
all vfio-pci devices are incompatible with ballooning, but allow user
opt-in should they have further insight into mediated devices.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
There is at least one guest (OS) such that although it does not rely on
the guarantees provided by ORB 1 word 9 bit (aka unlimited prefetch, aka
P bit) not being set, it fails to tell this to the machine.
Usually this ain't a big deal, as the original purpose of the P bit is to
allow for performance optimizations. vfio-ccw however can not provide the
guarantees required if the bit is not set.
It is not possible to implement support for the P bit not set without
transitioning to lower level protocols for vfio-ccw. So let's give the
user the opportunity to force setting the P bit, if the user knows this
is safe. For self modifying channel programs forcing the P bit is not
safe. If the P bit is forced for a self modifying channel program things
are expected to break in strange ways.
Let's also avoid warning multiple about P bit not set in the ORB in case
P bit is not told to be forced, and designate the affected vfio-ccw
device.
Signed-off-by: Halil Pasic <pasic@linux.ibm.com>
Suggested-by: Dong Jia Shi <bjsdjshi@linux.ibm.com>
Acked-by: Jason J. Herne <jjherne@linux.ibm.com>
Tested-by: Jason J. Herne <jjherne@linux.ibm.com>
Message-Id: <20180524175828.3143-2-pasic@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
No declaration of "hw/vfio/vfio-common.h" directly requires to include
the "exec/address-spaces.h" header. To simplify dependencies and
ease the upcoming cleanup of "exec/address-spaces.h", directly include
it in the source file where the declaration are used.
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20180528232719.4721-2-f4bug@amsat.org>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
A recent patch fixed leaks of the dynamically allocated vcdev->vdev.name
field in vfio_ccw_realize(), but we now have three freeing sites for it.
This is unfortunate and seems to indicate something is wrong with its
life cycle.
The root issue is that vcdev->vdev.name is set before vfio_get_device()
is called, which theoretically prevents to call vfio_put_device() to
do the freeing. Well actually, we could call it anyway because
vfio_put_base_device() is a nop if the device isn't attached, but this
would be confusing.
This patch hence moves all the logic of attaching the device, including
the "already attached" check, to a separate vfio_ccw_get_device() function,
counterpart of vfio_put_device(). While here, vfio_put_device() is renamed
to vfio_ccw_put_device() for consistency.
Signed-off-by: Greg Kurz <groug@kaod.org>
Message-Id: <152326891065.266543.9487977590811413472.stgit@bahia.lan>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
If the subchannel is already attached or if vfio_get_device() fails, the
code jumps to the 'out_device_err' label and doesn't free the string it
has just allocated.
The code should be reworked so that vcdev->vdev.name only gets set when
the device has been attached, and freed when it is about to be detached.
This could be achieved with the addition of a vfio_ccw_get_device()
function that would be the counterpart of vfio_put_device(). But this is
a more elaborate cleanup that should be done in a follow-up. For now,
let's just add calls to g_free() on the buggy error paths.
Signed-off-by: Greg Kurz <groug@kaod.org>
Message-Id: <152311222681.203086.8874800175539040298.stgit@bahia>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
The license text currently specifies "any version" of the GPL. It
is unlikely that GPL v1 was ever intended; change this to the
standard "or any later version" text.
Cc: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
Cc: Xiao Feng Ren <renxiaof@linux.vnet.ibm.com>
Cc: Pierre Morel <pmorel@linux.vnet.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
Acked-by: Pierre Morel <pmorel@linux.vnet.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
applied using ./scripts/clean-includes
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
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>
Commit 7da624e2 ("vfio: Test realized when using VFIOGroup.device_list
iterator") introduced a pointer to the Object DeviceState in the VFIO
common base-device and skipped non-realized devices as we iterate
VFIOGroup.device_list. While it missed to initialize the pointer for
the vfio-ccw case. Let's fix it.
Fixes: 7da624e2 ("vfio: Test realized when using VFIOGroup.device_list
iterator")
Cc: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Halil Pasic <pasic@linux.vnet.ibm.com>
Signed-off-by: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Message-Id: <20170718014926.44781-3-bjsdjshi@linux.vnet.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
When allocating memory for the vfio_irq_info parameter of the
VFIO_DEVICE_GET_IRQ_INFO ioctl, we used the wrong size. Let's
fix it by using the right size.
Reviewed-by: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
Signed-off-by: Jing Zhang <bjzhjing@linux.vnet.ibm.com>
Signed-off-by: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
Message-Id: <20170718014926.44781-2-bjsdjshi@linux.vnet.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Concurrent-sense data is currently not delivered. This patch stores
the concurrent-sense data to the subchannel if a unit check is pending
and the concurrent-sense bit is enabled. Then a TSCH can retreive the
right IRB data back to the guest.
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
Message-Id: <20170517004813.58227-13-bjsdjshi@linux.vnet.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Introduce a new callback on subchannel to handle ccw-request.
Realize the callback in vfio-ccw device. Besides, resort to
the event notifier handler to handling the ccw-request results.
1. Pread the I/O results via MMIO region.
2. Update the scsw info to guest.
3. Inject an I/O interrupt to notify guest the I/O result.
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Xiao Feng Ren <renxiaof@linux.vnet.ibm.com>
Signed-off-by: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
Message-Id: <20170517004813.58227-11-bjsdjshi@linux.vnet.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
vfio-ccw resorts to the eventfd mechanism to communicate with userspace.
We fetch the irqs info via the ioctl VFIO_DEVICE_GET_IRQ_INFO,
register a event notifier to get the eventfd fd which is sent
to kernel via the ioctl VFIO_DEVICE_SET_IRQS, then we can implement
read operation once kernel sends the signal.
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
Message-Id: <20170517004813.58227-10-bjsdjshi@linux.vnet.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
vfio-ccw provides an MMIO region for I/O operations. We fetch its
information via ioctls here, then we can use it performing I/O
instructions and retrieving I/O results later on.
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
Message-Id: <20170517004813.58227-9-bjsdjshi@linux.vnet.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
We use the IOMMU_TYPE1 of VFIO to realize the subchannels
passthrough, implement a vfio based subchannels passthrough
driver called "vfio-ccw".
Support qemu parameters in the style of:
"-device vfio-ccw,sysfsdev=$mdev_file_path,devno=xx.x.xxxx'
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Xiao Feng Ren <renxiaof@linux.vnet.ibm.com>
Signed-off-by: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
Message-Id: <20170517004813.58227-8-bjsdjshi@linux.vnet.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
