Commit Graph

108 Commits

Author SHA1 Message Date
Alex Williamson
db32d0f438 vfio/pci: Add option to disable GeForce quirks
These quirks are necessary for GeForce, but not for Quadro/GRID/Tesla
assignment.  Leaving them enabled is fully functional and provides the
most compatibility, but due to the unique NVIDIA MSI ACK behavior[1],
it also introduces latency in re-triggering the MSI interrupt.  This
overhead is typically negligible, but has been shown to adversely
affect some (very) high interrupt rate applications.  This adds the
vfio-pci device option "x-no-geforce-quirks=" which can be set to
"on" to disable this additional overhead.

A follow-on optimization for GeForce might be to make use of an
ioeventfd to allow KVM to trigger an irqfd in the kernel vfio-pci
driver, avoiding the bounce through userspace to handle this device
write.

[1] Background: the NVIDIA driver has been observed to issue a write
to the MMIO mirror of PCI config space in BAR0 in order to allow the
MSI interrupt for the device to retrigger.  Older reports indicated a
write of 0xff to the (read-only) MSI capability ID register, while
more recently a write of 0x0 is observed at config space offset 0x704,
non-architected, extended config space of the device (BAR0 offset
0x88704).  Virtualization of this range is only required for GeForce.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2018-02-06 11:08:27 -07:00
Alex Williamson
89d5202edc vfio/pci: Allow relocating MSI-X MMIO
Recently proposed vfio-pci kernel changes (v4.16) remove the
restriction preventing userspace from mmap'ing PCI BARs in areas
overlapping the MSI-X vector table.  This change is primarily intended
to benefit host platforms which make use of system page sizes larger
than the PCI spec recommendation for alignment of MSI-X data
structures (ie. not x86_64).  In the case of POWER systems, the SPAPR
spec requires the VM to program MSI-X using hypercalls, rendering the
MSI-X vector table unused in the VM view of the device.  However,
ARM64 platforms also support 64KB pages and rely on QEMU emulation of
MSI-X.  Regardless of the kernel driver allowing mmaps overlapping
the MSI-X vector table, emulation of the MSI-X vector table also
prevents direct mapping of device MMIO spaces overlapping this page.
Thanks to the fact that PCI devices have a standard self discovery
mechanism, we can try to resolve this by relocating the MSI-X data
structures, either by creating a new PCI BAR or extending an existing
BAR and updating the MSI-X capability for the new location.  There's
even a very slim chance that this could benefit devices which do not
adhere to the PCI spec alignment guidelines on x86_64 systems.

This new x-msix-relocation option accepts the following choices:

  off: Disable MSI-X relocation, use native device config (default)
  auto: Use a known good combination for the platform/device (none yet)
  bar0..bar5: Specify the target BAR for MSI-X data structures

If compatible, the target BAR will either be created or extended and
the new portion will be used for MSI-X emulation.

The first obvious user question with this option is how to determine
whether a given platform and device might benefit from this option.
In most cases, the answer is that it won't, especially on x86_64.
Devices often dedicate an entire BAR to MSI-X and therefore no
performance sensitive registers overlap the MSI-X area.  Take for
example:

# lspci -vvvs 0a:00.0
0a:00.0 Ethernet controller: Intel Corporation I350 Gigabit Network Connection
	...
	Region 0: Memory at db680000 (32-bit, non-prefetchable) [size=512K]
	Region 3: Memory at db7f8000 (32-bit, non-prefetchable) [size=16K]
	...
	Capabilities: [70] MSI-X: Enable+ Count=10 Masked-
		Vector table: BAR=3 offset=00000000
		PBA: BAR=3 offset=00002000

This device uses the 16K bar3 for MSI-X with the vector table at
offset zero and the pending bits arrary at offset 8K, fully honoring
the PCI spec alignment guidance.  The data sheet specifically refers
to this as an MSI-X BAR.  This device would not see a benefit from
MSI-X relocation regardless of the platform, regardless of the page
size.

However, here's another example:

# lspci -vvvs 02:00.0
02:00.0 Serial Attached SCSI controller: xxxxxxxx
	...
	Region 0: I/O ports at c000 [size=256]
	Region 1: Memory at ef640000 (64-bit, non-prefetchable) [size=64K]
	Region 3: Memory at ef600000 (64-bit, non-prefetchable) [size=256K]
	...
	Capabilities: [c0] MSI-X: Enable+ Count=16 Masked-
		Vector table: BAR=1 offset=0000e000
		PBA: BAR=1 offset=0000f000

Here the MSI-X data structures are placed on separate 4K pages at the
end of a 64KB BAR.  If our host page size is 4K, we're likely fine,
but at 64KB page size, MSI-X emulation at that location prevents the
entire BAR from being directly mapped into the VM address space.
Overlapping performance sensitive registers then starts to be a very
likely scenario on such a platform.  At this point, the user could
enable tracing on vfio_region_read and vfio_region_write to determine
more conclusively if device accesses are being trapped through QEMU.

Upon finding a device and platform in need of MSI-X relocation, the
next problem is how to choose target PCI BAR to host the MSI-X data
structures.  A few key rules to keep in mind for this selection
include:

 * There are only 6 BAR slots, bar0..bar5
 * 64-bit BARs occupy two BAR slots, 'lspci -vvv' lists the first slot
 * PCI BARs are always a power of 2 in size, extending == doubling
 * The maximum size of a 32-bit BAR is 2GB
 * MSI-X data structures must reside in an MMIO BAR

Using these rules, we can evaluate each BAR of the second example
device above as follows:

 bar0: I/O port BAR, incompatible with MSI-X tables
 bar1: BAR could be extended, incurring another 64KB of MMIO
 bar2: Unavailable, bar1 is 64-bit, this register is used by bar1
 bar3: BAR could be extended, incurring another 256KB of MMIO
 bar4: Unavailable, bar3 is 64bit, this register is used by bar3
 bar5: Available, empty BAR, minimum additional MMIO

A secondary optimization we might wish to make in relocating MSI-X
is to minimize the additional MMIO required for the device, therefore
we might test the available choices in order of preference as bar5,
bar1, and finally bar3.  The original proposal for this feature
included an 'auto' option which would choose bar5 in this case, but
various drivers have been found that make assumptions about the
properties of the "first" BAR or the size of BARs such that there
appears to be no foolproof automatic selection available, requiring
known good combinations to be sourced from users.  This patch is
pre-enabled for an 'auto' selection making use of a validated lookup
table, but no entries are yet identified.

Tested-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2018-02-06 11:08:26 -07:00
Alex Williamson
04f336b05f vfio/pci: Emulate BARs
The kernel provides similar emulation of PCI BAR register access to
QEMU, so up until now we've used that for things like BAR sizing and
storing the BAR address.  However, if we intend to resize BARs or add
BARs that don't exist on the physical device, we need to switch to the
pure QEMU emulation of the BAR.

Tested-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2018-02-06 11:08:25 -07:00
Alex Williamson
3a286732d1 vfio/pci: Add base BAR MemoryRegion
Add one more layer to our stack of MemoryRegions, this base region
allows us to register BARs independently of the vfio region or to
extend the size of BARs which do map to a region.  This will be
useful when we want hypervisor defined BARs or sections of BARs,
for purposes such as relocating MSI-X emulation.  We therefore call
msix_init() based on this new base MemoryRegion, while the quirks,
which only modify regions still operate on those sub-MemoryRegions.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2018-02-06 11:08:25 -07:00
David Gibson
fd56e0612b pci: Eliminate redundant PCIDevice::bus pointer
The bus pointer in PCIDevice is basically redundant with QOM information.
It's always initialized to the qdev_get_parent_bus(), the only difference
is the type.

Therefore this patch eliminates the field, instead creating a pci_get_bus()
helper to do the type mangling to derive it conveniently from the QOM
Device object underneath.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: Marcel Apfelbaum <marcel@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
2017-12-05 19:13:45 +02:00
Eduardo Habkost
a5fa336f11 pci: Add interface names to hybrid PCI devices
The following devices support both PCI Express and Conventional
PCI, by including special code to handle the QEMU_PCI_CAP_EXPRESS
flag and/or conditional pcie_endpoint_cap_init() calls:

* vfio-pci (is_express=1, but legacy PCI handled by
  vfio_populate_device())
* vmxnet3 (is_express=0, but PCIe handled by vmxnet3_realize())
* pvscsi (is_express=0, but PCIe handled by pvscsi_realize())
* virtio-pci (is_express=0, but PCIe handled by
  virtio_pci_dc_realize(), and additional legacy PCI code at
  virtio_pci_realize())
* base-xhci (is_express=1, but pcie_endpoint_cap_init() call
  is conditional on pci_bus_is_express(dev->bus)
  * Note that xhci does not clear QEMU_PCI_CAP_EXPRESS like the
    other hybrid devices

Cc: Dmitry Fleytman <dmitry@daynix.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Alex Williamson <alex.williamson@redhat.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Marcel Apfelbaum <marcel@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-10-15 05:54:42 +03:00
Alex Williamson
dfbee78db8 vfio/pci: Add NVIDIA GPUDirect Cliques support
NVIDIA has defined a specification for creating GPUDirect "cliques",
where devices with the same clique ID support direct peer-to-peer DMA.
When running on bare-metal, tools like NVIDIA's p2pBandwidthLatencyTest
(part of cuda-samples) determine which GPUs can support peer-to-peer
based on chipset and topology.  When running in a VM, these tools have
no visibility to the physical hardware support or topology.  This
option allows the user to specify hints via a vendor defined
capability.  For instance:

  <qemu:commandline>
    <qemu:arg value='-set'/>
    <qemu:arg value='device.hostdev0.x-nv-gpudirect-clique=0'/>
    <qemu:arg value='-set'/>
    <qemu:arg value='device.hostdev1.x-nv-gpudirect-clique=1'/>
    <qemu:arg value='-set'/>
    <qemu:arg value='device.hostdev2.x-nv-gpudirect-clique=1'/>
  </qemu:commandline>

This enables two cliques.  The first is a singleton clique with ID 0,
for the first hostdev defined in the XML (note that since cliques
define peer-to-peer sets, singleton clique offer no benefit).  The
subsequent two hostdevs are both added to clique ID 1, indicating
peer-to-peer is possible between these devices.

QEMU only provides validation that the clique ID is valid and applied
to an NVIDIA graphics device, any validation that the resulting
cliques are functional and valid is the user's responsibility.  The
NVIDIA specification allows a 4-bit clique ID, thus valid values are
0-15.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2017-10-03 12:57:36 -06:00
Alex Williamson
e3f79f3bd4 vfio/pci: Add virtual capabilities quirk infrastructure
If the hypervisor needs to add purely virtual capabilties, give us a
hook through quirks to do that.  Note that we determine the maximum
size for a capability based on the physical device, if we insert a
virtual capability, that can change.  Therefore if maximum size is
smaller after added virt capabilities, use that.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2017-10-03 12:57:36 -06:00
Alex Williamson
5b31c8229d vfio/pci: Do not unwind on error
If vfio_add_std_cap() errors then going to out prepends irrelevant
errors for capabilities we haven't attempted to add as we unwind our
recursive stack.  Just return error.

Fixes: 7ef165b9a8 ("vfio/pci: Pass an error object to vfio_add_capabilities")
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2017-10-03 12:57:35 -06:00
Philippe Mathieu-Daudé
96d2c2c574 vfio/pci: fix use of freed memory
hw/vfio/pci.c:308:29: warning: Use of memory after it is freed
        qemu_set_fd_handler(*pfd, NULL, NULL, vdev);
                            ^~~~

Reported-by: Clang Static Analyzer
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2017-07-26 11:38:18 -06:00
Alex Williamson
47985727e3 vfio/pci: Fixup v0 PCIe capabilities
Intel 82599 VFs report a PCIe capability version of 0, which is
invalid.  The earliest version of the PCIe spec used version 1.  This
causes Windows to fail startup on the device and it will be disabled
with error code 10.  Our choices are either to drop the PCIe cap on
such devices, which has the side effect of likely preventing the guest
from discovering any extended capabilities, or performing a fixup to
update the capability to the earliest valid version.  This implements
the latter.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2017-07-10 10:39:43 -06:00
Alex Williamson
7da624e26a vfio: Test realized when using VFIOGroup.device_list iterator
VFIOGroup.device_list is effectively our reference tracking mechanism
such that we can teardown a group when all of the device references
are removed.  However, we also use this list from our machine reset
handler for processing resets that affect multiple devices.  Generally
device removals are fully processed (exitfn + finalize) when this
reset handler is invoked, however if the removal is triggered via
another reset handler (piix4_reset->acpi_pcihp_reset) then the device
exitfn may run, but not finalize.  In this case we hit asserts when
we start trying to access PCI helpers since much of the PCI state of
the device is released.  To resolve this, add a pointer to the Object
DeviceState in our common base-device and skip non-realized devices
as we iterate.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2017-07-10 10:39:43 -06:00
Mao Zhongyi
2784127857 pci: Replace pci_add_capability2() with pci_add_capability()
After the patch 'Make errp the last parameter of pci_add_capability()',
pci_add_capability() and pci_add_capability2() now do exactly the same.
So drop the wrapper pci_add_capability() of pci_add_capability2(), then
replace the pci_add_capability2() with pci_add_capability() everywhere.

Cc: pbonzini@redhat.com
Cc: rth@twiddle.net
Cc: ehabkost@redhat.com
Cc: mst@redhat.com
Cc: dmitry@daynix.com
Cc: jasowang@redhat.com
Cc: marcel@redhat.com
Cc: alex.williamson@redhat.com
Cc: armbru@redhat.com
Suggested-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Mao Zhongyi <maozy.fnst@cn.fujitsu.com>
Reviewed-by: Marcel Apfelbaum <marcel@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-07-03 22:29:49 +03:00
Mao Zhongyi
9a7c2a5970 pci: Make errp the last parameter of pci_add_capability()
Add Error argument for pci_add_capability() to leverage the errp
to pass info on errors. This way is helpful for its callers to
make a better error handling when moving to 'realize'.

Cc: pbonzini@redhat.com
Cc: rth@twiddle.net
Cc: ehabkost@redhat.com
Cc: mst@redhat.com
Cc: jasowang@redhat.com
Cc: marcel@redhat.com
Cc: alex.williamson@redhat.com
Cc: armbru@redhat.com
Signed-off-by: Mao Zhongyi <maozy.fnst@cn.fujitsu.com>
Reviewed-by: Marcel Apfelbaum <marcel@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-07-03 22:29:49 +03:00
Mao Zhongyi
9a815774bb pci: Fix the wrong assertion.
pci_add_capability returns a strictly positive value on success,
correct asserts.

Cc: dmitry@daynix.com
Cc: jasowang@redhat.com
Cc: kraxel@redhat.com
Cc: alex.williamson@redhat.com
Cc: armbru@redhat.com
Cc: marcel@redhat.com
Signed-off-by: Mao Zhongyi <maozy.fnst@cn.fujitsu.com>
Reviewed-by: Marcel Apfelbaum <marcel@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-07-03 22:29:49 +03:00
Dong Jia Shi
6e4e6f0d40 vfio/pci: Fix incorrect error message
When the "No host device provided" error occurs, the hint message
that starts with "Use -vfio-pci," makes no sense, since "-vfio-pci"
is not a valid command line parameter.

Correct this by replacing "-vfio-pci" with "-device vfio-pci".

Signed-off-by: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2017-05-03 14:52:35 -06:00
Alex Williamson
d0d1cd70d1 vfio/pci: Improve extended capability comments, skip masked caps
Since commit 4bb571d857 ("pci/pcie: don't assume cap id 0 is
reserved") removes the internal use of extended capability ID 0, the
comment here becomes invalid.  However, peeling back the onion, the
code is still correct and we still can't seed the capability chain
with ID 0, unless we want to muck with using the version number to
force the header to be non-zero, which is much uglier to deal with.
The comment also now covers some of the subtleties of using cap ID 0,
such as transparently indicating absence of capabilities if none are
added.  This doesn't detract from the correctness of the referenced
commit as vfio in the kernel also uses capability ID zero to mask
capabilties.  In fact, we should skip zero capabilities precisely
because the kernel might also expose such a capability at the head
position and re-introduce the problem.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Tested-by: Peter Xu <peterx@redhat.com>
Reported-by: Jintack Lim <jintack@cs.columbia.edu>
Tested-by: Jintack Lim <jintack@cs.columbia.edu>
2017-02-22 13:19:58 -07:00
Alex Williamson
35c7cb4caf vfio/pci: Report errors from qdev_unplug() via device request
Currently we ignore this error, report it with error_reportf_err()

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
2017-02-22 13:19:58 -07:00
Cao jin
ee640c625e pci: Convert msix_init() to Error and fix callers
msix_init() reports errors with error_report(), which is wrong when
it's used in realize().  The same issue was fixed for msi_init() in
commit 1108b2f. In order to make the API change as small as possible,
leave the return value check to later patch.

For some devices(like e1000e, vmxnet3, nvme) who won't fail because of
msix_init's failure, suppress the error report by passing NULL error
object.

Bonus: add comment for msix_init.

CC: Jiri Pirko <jiri@resnulli.us>
CC: Gerd Hoffmann <kraxel@redhat.com>
CC: Dmitry Fleytman <dmitry@daynix.com>
CC: Jason Wang <jasowang@redhat.com>
CC: Michael S. Tsirkin <mst@redhat.com>
CC: Hannes Reinecke <hare@suse.de>
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: Alex Williamson <alex.williamson@redhat.com>
CC: Markus Armbruster <armbru@redhat.com>
CC: Marcel Apfelbaum <marcel@redhat.com>
Signed-off-by: Cao jin <caoj.fnst@cn.fujitsu.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-02-01 03:37:18 +02:00
Cao jin
8907379204 vfio: remove a duplicated word in comments
Signed-off-by: Cao jin <caoj.fnst@cn.fujitsu.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2017-01-24 23:26:53 +03:00
Yongji Xie
95251725e3 vfio: Add support for mmapping sub-page MMIO BARs
Now the kernel commit 05f0c03fbac1 ("vfio-pci: Allow to mmap
sub-page MMIO BARs if the mmio page is exclusive") allows VFIO
to mmap sub-page BARs. This is the corresponding QEMU patch.
With those patches applied, we could passthrough sub-page BARs
to guest, which can help to improve IO performance for some devices.

In this patch, we expand MemoryRegions of these sub-page
MMIO BARs to PAGE_SIZE in vfio_pci_write_config(), so that
the BARs could be passed to KVM ioctl KVM_SET_USER_MEMORY_REGION
with a valid size. The expanding size will be recovered when
the base address of sub-page BAR is changed and not page aligned
any more in guest. And we also set the priority of these BARs'
memory regions to zero in case of overlap with BARs which share
the same page with sub-page BARs in guest.

Signed-off-by: Yongji Xie <xyjxie@linux.vnet.ibm.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-10-31 09:53:04 -06:00
Ido Yariv
a52a4c4717 vfio/pci: fix out-of-sync BAR information on reset
When a PCI device is reset, pci_do_device_reset resets all BAR addresses
in the relevant PCIDevice's config buffer.

The VFIO configuration space stays untouched, so the guest OS may choose
to skip restoring the BAR addresses as they would seem intact. The PCI
device may be left non-operational.
One example of such a scenario is when the guest exits S3.

Fix this by resetting the BAR addresses in the VFIO configuration space
as well.

Signed-off-by: Ido Yariv <ido@wizery.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-10-31 09:53:04 -06:00
Cao jin
893bfc3cc8 vfio: fix duplicate function call
When vfio device is reset(encounter FLR, or bus reset), if need to do
bus reset(vfio_pci_hot_reset_one is called), vfio_pci_pre_reset &
vfio_pci_post_reset will be called twice.

Signed-off-by: Cao jin <caoj.fnst@cn.fujitsu.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-10-17 10:58:03 -06:00
Eric Auger
4a94626850 vfio/pci: Handle host oversight
In case the end-user calls qemu with -vfio-pci option without passing
either sysfsdev or host property value, the device is interpreted as
0000:00:00.0. Let's create a specific error message to guide the end-user.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-10-17 10:58:02 -06:00
Eric Auger
e04cff9d97 vfio/pci: Remove vfio_populate_device returned value
The returned value (either -errno or -1) is not used anymore by the caller,
vfio_realize, since the error now is stored in the error object. So let's
remove it.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-10-17 10:58:02 -06:00
Eric Auger
ec3bcf424e vfio/pci: Remove vfio_msix_early_setup returned value
The returned value is not used anymore by the caller, vfio_realize,
since the error now is stored in the error object. So let's remove it.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-10-17 10:58:01 -06:00
Eric Auger
1a22aca1d0 vfio/pci: Conversion to realize
This patch converts VFIO PCI to realize function.

Also original initfn errors now are propagated using QEMU
error objects. All errors are formatted with the same pattern:
"vfio: %s: the error description"

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-10-17 10:58:01 -06:00
Eric Auger
59f7d6743c vfio: Pass an error object to vfio_get_device
Pass an error object to prepare for migration to VFIO-PCI realize.

In vfio platform vfio_base_device_init we currently just report the
error. Subsequent patches will propagate the error up to the realize
function.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-10-17 10:58:00 -06:00
Eric Auger
1b808d5be0 vfio: Pass an error object to vfio_get_group
Pass an error object to prepare for migration to VFIO-PCI realize.

For the time being let's just simply report the error in
vfio platform's vfio_base_device_init(). A subsequent patch will
duly propagate the error up to vfio_platform_realize.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-10-17 10:57:59 -06:00
Eric Auger
7237011d05 vfio/pci: Pass an error object to vfio_pci_igd_opregion_init
Pass an error object to prepare for migration to VFIO-PCI realize.

In vfio_probe_igd_bar4_quirk, simply report the error.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-10-17 10:57:59 -06:00
Eric Auger
7ef165b9a8 vfio/pci: Pass an error object to vfio_add_capabilities
Pass an error object to prepare for migration to VFIO-PCI realize.
The error is cascaded downto vfio_add_std_cap and then vfio_msi(x)_setup,
vfio_setup_pcie_cap.

vfio_add_ext_cap does not return anything else than 0 so let's transform
it into a void function.

Also use pci_add_capability2 which takes an error object.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-10-17 10:57:58 -06:00
Eric Auger
7dfb34247e vfio/pci: Pass an error object to vfio_intx_enable
Pass an error object to prepare for migration to VFIO-PCI realize.

The error object is propagated down to vfio_intx_enable_kvm().

The three other callers, vfio_intx_enable_kvm(), vfio_msi_disable_common()
and vfio_pci_post_reset() do not propagate the error and simply call
error_reportf_err() with the ERR_PREFIX formatting.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-10-17 10:57:58 -06:00
Eric Auger
008d0e2d7b vfio/pci: Pass an error object to vfio_msix_early_setup
Pass an error object to prepare for migration to VFIO-PCI realize.
The returned value will be removed later on.

We now format an error in case of reading failure for
- the MSIX flags
- the MSIX table,
- the MSIX PBA.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-10-17 10:57:58 -06:00
Eric Auger
2312d907dd vfio/pci: Pass an error object to vfio_populate_device
Pass an error object to prepare for migration to VFIO-PCI realize.
The returned value will be removed later on.

The case where error recovery cannot be enabled is not converted into
an error object but directly reported through error_report, as before.
Populating an error instead would cause the future realize function to
fail, which is not wanted.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-10-17 10:57:57 -06:00
Eric Auger
cde4279baa vfio/pci: Pass an error object to vfio_populate_vga
Pass an error object to prepare for the same operation in
vfio_populate_device. Eventually this contributes to the migration
to VFIO-PCI realize.

We now report an error on vfio_get_region_info failure.

vfio_probe_igd_bar4_quirk is not involved in the migration to realize
and simply calls error_reportf_err.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-10-17 10:57:57 -06:00
Eric Auger
426ec9049e vfio/pci: Use local error object in vfio_initfn
To prepare for migration to realize, let's use a local error
object in vfio_initfn. Also let's use the same error prefix for all
error messages.

On top of the 1-1 conversion, we start using a common error prefix for
all error messages. We also introduce a similar warning prefix which will
be used later on.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-10-17 10:57:56 -06:00
David Gibson
6d17a018d0 vfio/pci: Fix regression in MSI routing configuration
d1f6af6 "kvm-irqchip: simplify kvm_irqchip_add_msi_route" was a cleanup
of kvmchip routing configuration, that was mostly intended for x86.
However, it also contains a subtle change in behaviour which breaks EEH[1]
error recovery on certain VFIO passthrough devices on spapr guests.  So far
it's only been seen on a BCM5719 NIC on a POWER8 server, but there may be
other hardware with the same problem.  It's also possible there could be
circumstances where it causes a bug on x86 as well, though I don't know of
any obvious candidates.

Prior to d1f6af6, both vfio_msix_vector_do_use() and
vfio_add_kvm_msi_virq() used msg == NULL as a special flag to mark this
as the "dummy" vector used to make the host hardware state sync with the
guest expected hardware state in terms of MSI configuration.

Specifically that flag caused vfio_add_kvm_msi_virq() to become a no-op,
meaning the dummy irq would always be delivered via qemu. d1f6af6 changed
vfio_add_kvm_msi_virq() so it takes a vector number instead of the msg
parameter, and determines the correct message itself.  The test for !msg
was removed, and not replaced with anything there or in the caller.

With an spapr guest which has a VFIO device, if an EEH error occurs on the
host hardware, then the device will be isolated then reset.  This is a
combination of host and guest action, mediated by some EEH related
hypercalls.  I haven't fully traced the mechanics, but somehow installing
the kvm irqchip route for the dummy irq on the BCM5719 means that after EEH
reset and recovery, at least some irqs are no longer delivered to the
guest.

In particular, the guest never gets the link up event, and so the NIC is
effectively dead.

[1] EEH (Enhanced Error Handling) is an IBM POWER server specific PCI-*
    error reporting and recovery mechanism.  The concept is somewhat
    similar to PCI-E AER, but the details are different.

Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1373802

Cc: Alex Williamson <alex.williamson@redhat.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Gavin Shan <gwshan@au1.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Cc: qemu-stable@nongnu.org
Fixes: d1f6af6a17 ("kvm-irqchip: simplify kvm_irqchip_add_msi_route")
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-09-15 10:41:36 -06:00
Peter Xu
3f1fea0fb5 kvm-irqchip: do explicit commit when update irq
In the past, we are doing gsi route commit for each irqchip route
update. This is not efficient if we are updating lots of routes in the
same time. This patch removes the committing phase in
kvm_irqchip_update_msi_route(). Instead, we do explicit commit after all
routes updated.

Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-07-21 20:44:19 +03:00
Peter Xu
d1f6af6a17 kvm-irqchip: simplify kvm_irqchip_add_msi_route
Changing the original MSIMessage parameter in kvm_irqchip_add_msi_route
into the vector number. Vector index provides more information than the
MSIMessage, we can retrieve the MSIMessage using the vector easily. This
will avoid fetching MSIMessage every time before adding MSI routes.

Meanwhile, the vector info will be used in the coming patches to further
enable gsi route update notifications.

Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-07-21 20:44:18 +03:00
Alex Williamson
383a7af7ec vfio/pci: Hide ARI capability
QEMU supports ARI on downstream ports and assigned devices may support
ARI in their extended capabilities.  The endpoint ARI capability
specifies the next function, such that the OS doesn't need to walk
each possible function, however this next function is relative to the
host, not the guest.  This leads to device discovery issues when we
combine separate functions into virtual multi-function packages in a
guest.  For example, SR-IOV VFs are not enumerated by simply probing
the function address space, therefore the ARI next-function field is
zero.  When we combine multiple VFs together as a multi-function
device in the guest, the guest OS identifies ARI is enabled, relies on
this next-function field, and stops looking for additional function
after the first is found.

Long term we should expose the ARI capability to the guest to enable
configurations with more than 8 functions per slot, but this requires
additional QEMU PCI infrastructure to manage the next-function field
for multiple, otherwise independent devices.  In the short term,
hiding this capability allows equivalent functionality to what we
currently have on non-express chipsets.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Marcel Apfelbaum <marcel@redhat.com>
2016-07-18 10:55:17 -06:00
Cao jin
1108b2f8a9 pci: Convert msi_init() to Error and fix callers to check it
msi_init() reports errors with error_report(), which is wrong
when it's used in realize().

Fix by converting it to Error.

Fix its callers to handle failure instead of ignoring it.

For those callers who don't handle the failure, it might happen:
when user want msi on, but he doesn't get what he want because of
msi_init fails silently.

cc: Gerd Hoffmann <kraxel@redhat.com>
cc: John Snow <jsnow@redhat.com>
cc: Dmitry Fleytman <dmitry@daynix.com>
cc: Jason Wang <jasowang@redhat.com>
cc: Michael S. Tsirkin <mst@redhat.com>
cc: Hannes Reinecke <hare@suse.de>
cc: Paolo Bonzini <pbonzini@redhat.com>
cc: Alex Williamson <alex.williamson@redhat.com>
cc: Markus Armbruster <armbru@redhat.com>
cc: Marcel Apfelbaum <marcel@redhat.com>

Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Cao jin <caoj.fnst@cn.fujitsu.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
2016-07-05 13:14:41 +03:00
Alex Williamson
e37dac06dc vfio/pci: Hide SR-IOV capability
The kernel currently exposes the SR-IOV capability as read-only
through vfio-pci.  This is sufficient to protect the host kernel, but
has the potential to confuse guests without further virtualization.
In particular, OVMF tries to size the VF BARs and comes up with absurd
results, ending with an assert.  There's not much point in adding
virtualization to a read-only capability, so we simply hide it for
now.  If the kernel ever enables SR-IOV virtualization, we should
easily be able to test it through VF BAR sizing or explicit flags.

Testing whether we should parse extended capabilities is also pulled
into the function to keep these assumptions in one place.

Tested-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-06-30 13:00:23 -06:00
Chen Fan
325ae8d548 vfio: add pcie extended capability support
For vfio pcie device, we could expose the extended capability on
PCIE bus. due to add a new pcie capability at the tail of the chain,
in order to avoid config space overwritten, we introduce a copy config
for parsing extended caps. and rebuild the pcie extended config space.

Signed-off-by: Chen Fan <chen.fan.fnst@cn.fujitsu.com>
Tested-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-06-30 13:00:23 -06:00
Paolo Bonzini
02d0e09503 os-posix: include sys/mman.h
qemu/osdep.h checks whether MAP_ANONYMOUS is defined, but this check
is bogus without a previous inclusion of sys/mman.h.  Include it in
sysemu/os-posix.h and remove it from everywhere else.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-06-16 18:39:03 +02:00
Alex Williamson
6ced0bba70 vfio/pci: Add a separate option for IGD OpRegion support
The IGD OpRegion is enabled automatically when running in legacy mode,
but it can sometimes be useful in universal passthrough mode as well.
Without an OpRegion, output spigots don't work, and even though Intel
doesn't officially support physical outputs in UPT mode, it's a
useful feature.  Note that if an OpRegion is enabled but a monitor is
not connected, some graphics features will be disabled in the guest
versus a headless system without an OpRegion, where they would work.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Gerd Hoffmann <kraxel@redhat.com>
Tested-by: Gerd Hoffmann <kraxel@redhat.com>
2016-05-26 11:12:03 -06:00
Alex Williamson
c4c45e943e vfio/pci: Intel graphics legacy mode assignment
Enable quirks to support SandyBridge and newer IGD devices as primary
VM graphics.  This requires new vfio-pci device specific regions added
in kernel v4.6 to expose the IGD OpRegion, the shadow ROM, and config
space access to the PCI host bridge and LPC/ISA bridge.  VM firmware
support, SeaBIOS only so far, is also required for reserving memory
regions for IGD specific use.  In order to enable this mode, IGD must
be assigned to the VM at PCI bus address 00:02.0, it must have a ROM,
it must be able to enable VGA, it must have or be able to create on
its own an LPC/ISA bridge of the proper type at PCI bus address
00:1f.0 (sorry, not compatible with Q35 yet), and it must have the
above noted vfio-pci kernel features and BIOS.  The intention is that
to enable this mode, a user simply needs to assign 00:02.0 from the
host to 00:02.0 in the VM:

  -device vfio-pci,host=0000:00:02.0,bus=pci.0,addr=02.0

and everything either happens automatically or it doesn't.  In the
case that it doesn't, we leave error reports, but assume the device
will operate in universal passthrough mode (UPT), which doesn't
require any of this, but has a much more narrow window of supported
devices, supported use cases, and supported guest drivers.

When using IGD in this mode, the VM firmware is required to reserve
some VM RAM for the OpRegion (on the order or several 4k pages) and
stolen memory for the GTT (up to 8MB for the latest GPUs).  An
additional option, x-igd-gms allows the user to specify some amount
of additional memory (value is number of 32MB chunks up to 512MB) that
is pre-allocated for graphics use.  TBH, I don't know of anything that
requires this or makes use of this memory, which is why we don't
allocate any by default, but the specification suggests this is not
actually a valid combination, so the option exists as a workaround.
Please report if it's actually necessary in some environment.

See code comments for further discussion about the actual operation
of the quirks necessary to assign these devices.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Gerd Hoffmann <kraxel@redhat.com>
Tested-by: Gerd Hoffmann <kraxel@redhat.com>
2016-05-26 11:12:01 -06:00
Alex Williamson
581406e0e3 vfio/pci: Setup BAR quirks after capabilities probing
Capability probing modifies wmask, which quirks may be interested in
changing themselves.  Apply our BAR quirks after the capability scan
to make this possible.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Gerd Hoffmann <kraxel@redhat.com>
Tested-by: Gerd Hoffmann <kraxel@redhat.com>
2016-05-26 11:12:00 -06:00
Alex Williamson
182bca4592 vfio/pci: Consolidate VGA setup
Combine VGA discovery and registration.  Quirks can have dependencies
on BARs, so the quirks push out until after we've scanned the BARs.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Gerd Hoffmann <kraxel@redhat.com>
Tested-by: Gerd Hoffmann <kraxel@redhat.com>
2016-05-26 11:11:58 -06:00
Alex Williamson
4225f2b670 vfio/pci: Fix return of vfio_populate_vga()
This function returns success if either we setup the VGA region or
the host vfio doesn't return enough regions to support the VGA index.
This latter case doesn't make any sense.  If we're asked to populate
VGA, fail if it doesn't exist and let the caller decide if that's
important.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Gerd Hoffmann <kraxel@redhat.com>
Tested-by: Gerd Hoffmann <kraxel@redhat.com>
2016-05-26 11:11:56 -06:00
Neo Jia
062ed5d8d6 vfio/pci: replace fixed string limit by g_strdup_printf
A trivial change to remove string limit by using g_strdup_printf

Tested-by: Neo Jia <cjia@nvidia.com>
Signed-off-by: Neo Jia <cjia@nvidia.com>
Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-03-10 20:50:43 -07:00