Commit Graph

65 Commits

Author SHA1 Message Date
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
Alex Williamson
e593c0211b vfio/pci: Split out VGA setup
This could be setup later by device specific code, such as IGD
initialization.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-03-10 20:50:41 -07:00
Alex Williamson
e2e5ee9c56 vfio/pci: Fixup PCI option ROMs
Devices like Intel graphics are known to not only have bad checksums,
but also the wrong device ID.  This is not so surprising given that
the video BIOS is typically part of the system firmware image rather
that embedded into the device and needs to support any IGD device
installed into the system.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-03-10 20:50:39 -07:00
Alex Williamson
2d82f8a3cd vfio/pci: Convert all MemoryRegion to dynamic alloc and consistent functions
Match common vfio code with setup, exit, and finalize functions for
BAR, quirk, and VGA management.  VGA is also changed to dynamic
allocation to match the other MemoryRegions.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-03-10 20:50:38 -07:00
Alex Williamson
db0da029a1 vfio: Generalize region support
Both platform and PCI vfio drivers create a "slow", I/O memory region
with one or more mmap memory regions overlayed when supported by the
device. Generalize this to a set of common helpers in the core that
pulls the region info from vfio, fills the region data, configures
slow mapping, and adds helpers for comleting the mmap, enable/disable,
and teardown.  This can be immediately used by the PCI MSI-X code,
which needs to mmap around the MSI-X vector table.

This also changes VFIORegion.mem to be dynamically allocated because
otherwise we don't know how the caller has allocated VFIORegion and
therefore don't know whether to unreference it to destroy the
MemoryRegion or not.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-03-10 20:03:16 -07:00
Alex Williamson
469002263a vfio: Wrap VFIO_DEVICE_GET_REGION_INFO
In preparation for supporting capability chains on regions, wrap
ioctl(VFIO_DEVICE_GET_REGION_INFO) so we don't duplicate the code for
each caller.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-03-10 09:39:07 -07:00
Alex Williamson
7df9381b7a vfio: Add sysfsdev property for pci & platform
vfio-pci currently requires a host= parameter, which comes in the
form of a PCI address in [domain:]<bus:slot.function> notation.  We
expect to find a matching entry in sysfs for that under
/sys/bus/pci/devices/.  vfio-platform takes a similar approach, but
defines the host= parameter to be a string, which can be matched
directly under /sys/bus/platform/devices/.  On the PCI side, we have
some interest in using vfio to expose vGPU devices.  These are not
actual discrete PCI devices, so they don't have a compatible host PCI
bus address or a device link where QEMU wants to look for it.  There's
also really no requirement that vfio can only be used to expose
physical devices, a new vfio bus and iommu driver could expose a
completely emulated device.  To fit within the vfio framework, it
would need a kernel struct device and associated IOMMU group, but
those are easy constraints to manage.

To support such devices, which would include vGPUs, that honor the
VFIO PCI programming API, but are not necessarily backed by a unique
PCI address, add support for specifying any device in sysfs.  The
vfio API already has support for probing the device type to ensure
compatibility with either vfio-pci or vfio-platform.

With this, a vfio-pci device could either be specified as:

-device vfio-pci,host=02:00.0

or

-device vfio-pci,sysfsdev=/sys/devices/pci0000:00/0000:00:1c.0/0000:02:00.0

or even

-device vfio-pci,sysfsdev=/sys/bus/pci/devices/0000:02:00.0

When vGPU support comes along, this might look something more like:

-device vfio-pci,sysfsdev=/sys/devices/virtual/intel-vgpu/vgpu0@0000:00:02.0

NB - This is only a made up example path

The same change is made for vfio-platform, specifying sysfsdev has
precedence over the old host option.

Tested-by: Eric Auger <eric.auger@linaro.org>
Reviewed-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-03-10 09:39:07 -07:00
Wei Yang
b58b17f744 vfio/pci: use PCI_MSIX_FLAGS on retrieving the MSIX entries
Even PCI_CAP_FLAGS has the same value as PCI_MSIX_FLAGS, the later one is
the more proper on retrieving MSIX entries.

This patch uses PCI_MSIX_FLAGS to retrieve the MSIX entries.

Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-02-19 09:42:32 -07:00
Wei Yang
3fc1c182c1 vfio/pci: replace 1 with PCI_CAP_LIST_NEXT to make code self-explain
Use the macro PCI_CAP_LIST_NEXT instead of 1, so that the code would be
more self-explain.

This patch makes this change and also fixs one typo in comment.

Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-02-19 09:42:29 -07:00
Chen Fan
88caf177ac vfio: make the 4 bytes aligned for capability size
this function search the capability from the end, the last
size should 0x100 - pos, not 0xff - pos.

Signed-off-by: Chen Fan <chen.fan.fnst@cn.fujitsu.com>
Reviewed-by: Marcel Apfelbaum <marcel@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-02-19 09:42:28 -07:00
Peter Maydell
c6eacb1ac0 hw/vfio: Clean up includes
Clean up includes so that osdep.h is included first and headers
which it implies are not included manually.

This commit was created with scripts/clean-includes.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1453832250-766-22-git-send-email-peter.maydell@linaro.org
2016-01-29 15:07:24 +00:00
Alex Williamson
95239e1625 vfio/pci: Lazy PBA emulation
The PCI spec recommends devices use additional alignment for MSI-X
data structures to allow software to map them to separate processor
pages.  One advantage of doing this is that we can emulate those data
structures without a significant performance impact to the operation
of the device.  Some devices fail to implement that suggestion and
assigned device performance suffers.

One such case of this is a Mellanox MT27500 series, ConnectX-3 VF,
where the MSI-X vector table and PBA are aligned on separate 4K
pages.  If PBA emulation is enabled, performance suffers.  It's not
clear how much value we get from PBA emulation, but the solution here
is to only lazily enable the emulated PBA when a masked MSI-X vector
fires.  We then attempt to more aggresively disable the PBA memory
region any time a vector is unmasked.  The expectation is then that
a typical VM will run entirely with PBA emulation disabled, and only
when used is that emulation re-enabled.

Reported-by: Shyam Kaushik <shyam.kaushik@gmail.com>
Tested-by: Shyam Kaushik <shyam.kaushik@gmail.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-01-19 11:33:42 -07:00
Markus Armbruster
bdd81addf4 vfio: Use g_new() & friends where that makes obvious sense
g_new(T, n) is neater than g_malloc(sizeof(T) * n).  It's also safer,
for two reasons.  One, it catches multiplication overflowing size_t.
Two, it returns T * rather than void *, which lets the compiler catch
more type errors.

This commit only touches allocations with size arguments of the form
sizeof(T).  Same Coccinelle semantic patch as in commit b45c03f.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-11-10 12:11:08 -07:00
Alex Williamson
0282abf078 vfio/pci: Hide device PCIe capability on non-express buses for PCIe VMs
When we have a PCIe VM, such as Q35, guests start to care more about
valid configurations of devices relative to the VM view of the PCI
topology.  Windows will error with a Code 10 for an assigned device if
a PCIe capability is found for a device on a conventional bus.  We
also have the possibility of IOMMUs, like VT-d, where the where the
guest may be acutely aware of valid express capabilities on physical
hardware.

Some devices, like tg3 are adversely affected by this due to driver
dependencies on the PCIe capability.  The only solution for such
devices is to attach them to an express capable bus in the VM.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-11-10 12:11:08 -07:00
Pavel Fedin
dc9f06ca81 kvm: Pass PCI device pointer to MSI routing functions
In-kernel ITS emulation on ARM64 will require to supply requester IDs.
These IDs can now be retrieved from the device pointer using new
pci_requester_id() function.

This patch adds pci_dev pointer to KVM GSI routing functions and makes
callers passing it.

x86 architecture does not use requester IDs, but hw/i386/kvm/pci-assign.c
also made passing PCI device pointer instead of NULL for consistency with
the rest of the code.

Signed-off-by: Pavel Fedin <p.fedin@samsung.com>
Message-Id: <ce081423ba2394a4efc30f30708fca07656bc500.1444916432.git.p.fedin@samsung.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-10-19 10:13:07 +02:00
Alex Williamson
89dcccc593 vfio/pci: Add emulated PCI IDs
Specifying an emulated PCI vendor/device ID can be useful for testing
various quirk paths, even though the behavior and functionality of
the device with bogus IDs is fully unsupportable.  We need to use a
uint32_t for the vendor/device IDs, even though the registers
themselves are only 16-bit in order to be able to determine whether
the value is valid and user set.

The same support is added for subsystem vendor/device ID, though these
have the possibility of being useful and supported for more than a
testing tool.  An emulated platform might want to impose their own
subsystem IDs or at least hide the physical subsystem ID.  Windows
guests will often reinstall drivers due to a change in subsystem IDs,
something that VM users may want to avoid.  Of course careful
attention would be required to ensure that guest drivers do not rely
on the subsystem ID as a basis for device driver quirks.

All of these options are added using the standard experimental option
prefix and should not be considered stable.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-09-23 13:04:49 -06:00
Alex Williamson
ff635e3775 vfio/pci: Cache vendor and device ID
Simplify access to commonly referenced PCI vendor and device ID by
caching it on the VFIOPCIDevice struct.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-09-23 13:04:49 -06:00
Alex Williamson
c9c5000991 vfio/pci: Move AMD device specific reset to quirks
This is just another quirk, for reset rather than affecting memory
regions.  Move it to our new quirks file.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-09-23 13:04:49 -06:00
Alex Williamson
c00d61d8fa vfio/pci: Split quirks to a separate file
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-09-23 13:04:45 -06:00
Alex Williamson
78f33d2bfd vfio/pci: Extract PCI structures to a separate header
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-09-23 13:04:44 -06:00
Alex Williamson
5e15d79b86 vfio: Change polarity of our no-mmap option
The default should be to allow mmap and new drivers shouldn't need to
expose an option or set it to other than the allocation default in
their initfn.  Take advantage of the experimental flag to change this
option to the correct polarity.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-09-23 13:04:44 -06:00
Alex Williamson
46746dbaa8 vfio/pci: Make interrupt bypass runtime configurable
Tracing is more effective when we can completely disable all KVM
bypass paths.  Make these runtime rather than build-time configurable.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-09-23 13:04:44 -06:00
Alex Williamson
0de70dc7ba vfio/pci: Rename MSI/X functions for easier tracing
This allows vfio_msi* tracing.  The MSI/X interrupt tracing is also
pulled out of #ifdef DEBUG_VFIO to avoid a recompile for tracing this
path.  A few cycles to read the message is hardly anything if we're
already in QEMU.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-09-23 13:04:43 -06:00
Alex Williamson
870cb6f104 vfio/pci: Rename INTx functions for easier tracing
Rename functions and tracing callbacks so that we can trace vfio_intx*
to see all the INTx related activities.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-09-23 13:04:43 -06:00
Alex Williamson
b5bd049fa9 vfio/pci: Cleanup vfio_early_setup_msix() error path
With the addition of the Chelsio quirk we have an error path out of
vfio_early_setup_msix() that doesn't free the allocated VFIOMSIXInfo
struct.  This doesn't introduce a leak as it still gets freed in the
vfio_put_device() path, but it's complicated and sloppy to rely on
that.  Restructure to free the allocated data on error and only link
it into the vdev on success.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Reported-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
2015-09-23 13:04:43 -06:00
Alex Williamson
d451008e0f vfio/pci: Cleanup RTL8168 quirk and tracing
There's quite a bit of cleanup that can be done to the RTL8168 quirk,
as well as the tracing to prevent a spew of uninteresting accesses
for anything else the driver might choose to use the window registers
for besides the MSI-X table.  There should be no functional change,
but it's now possible to get compact and useful traces by enabling
vfio_rtl8168_quirk*, ex:

vfio_rtl8168_quirk_write 0000:04:00.0 [address]: 0x1f000
vfio_rtl8168_quirk_read 0000:04:00.0 [address]: 0x8001f000
vfio_rtl8168_quirk_read 0000:04:00.0 [data]: 0xfee0100c
vfio_rtl8168_quirk_write 0000:04:00.0 [address]: 0x1f004
vfio_rtl8168_quirk_read 0000:04:00.0 [address]: 0x8001f004
vfio_rtl8168_quirk_read 0000:04:00.0 [data]: 0x0
vfio_rtl8168_quirk_write 0000:04:00.0 [address]: 0x1f008
vfio_rtl8168_quirk_read 0000:04:00.0 [address]: 0x8001f008
vfio_rtl8168_quirk_read 0000:04:00.0 [data]: 0x49b1
vfio_rtl8168_quirk_write 0000:04:00.0 [address]: 0x1f00c
vfio_rtl8168_quirk_read 0000:04:00.0 [address]: 0x8001f00c
vfio_rtl8168_quirk_read 0000:04:00.0 [data]: 0x0

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-09-23 13:04:42 -06:00
Veres Lajos
67cc32ebfd typofixes - v4
Signed-off-by: Veres Lajos <vlajos@gmail.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2015-09-11 10:45:43 +03:00
Daniel P. Berrange
d7646f241c maint: remove unused include for dirent.h
A number of files were including dirent.h but not using any
of the functions it provides

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2015-09-11 10:21:38 +03:00
Alex Williamson
759b484c5d vfio/pci: Fix bootindex
bootindex was incorrectly changed to a device Property during the
platform code split, resulting in it no longer working.  Remove it.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Cc: qemu-stable@nongnu.org # v2.3+
2015-07-22 14:56:01 -06:00
Alex Williamson
69970fcef9 vfio/pci: Fix RTL8168 NIC quirks
The RTL8168 quirk correctly describes using bit 31 as a signal to
mark a latch/completion, but the code mistakenly uses bit 28.  This
causes the Realtek driver to spin on this register for quite a while,
20k cycles on Windows 7 v7.092 driver.  Then it gets frustrated and
tries to set the bit itself and spins for another 20k cycles.  For
some this still results in a working driver, for others not.  About
the only thing the code really does in its current form is protect
the guest from sneaking in writes to the real hardware MSI-X table.
The fix is obviously to use bit 31 as we document that we should.

The other problem doesn't seem to affect current drivers as nobody
seems to use these window registers for writes to the MSI-X table, but
we need to use the stored data when a write is triggered, not the
value of the current write, which only provides the offset.

Note that only the Windows drivers from Realtek seem to use these
registers, the Microsoft drivers provided with Windows 8.1 do not
access them, nor do Linux in-kernel drivers.

Link: https://bugs.launchpad.net/qemu/+bug/1384892
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Cc: qemu-stable@nongnu.org # v2.1+
2015-07-22 14:56:01 -06:00
Gabriel Laupre
4330296996 vfio/pci : Add pba_offset PCI quirk for Chelsio T5 devices
Fix pba_offset initialization value for Chelsio T5 Virtual Function
device. The T5 hardware has a bug in it where it reports a Pending Interrupt
Bit Array Offset of 0x8000 for its SR-IOV Virtual Functions instead
of the 0x1000 that the hardware actually uses internally. As the hardware
doesn't return the correct pba_offset value, add a quirk to instead
return a hardcoded value of 0x1000 when a Chelsio T5 VF device is
detected.

This bug has been fixed in the Chelsio's next chip series T6 but there are
no plans to respin the T5 ASIC for this bug. It is just documented in the
T5 Errata and left it at that.

Signed-off-by: Gabriel Laupre <glaupre@chelsio.com>
Reviewed-by: Bandan Das <bsd@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-07-06 12:15:15 -06:00
Eric Auger
1c9b71a731 kvm: rename kvm_irqchip_[add,remove]_irqfd_notifier with gsi suffix
Anticipating for the introduction of new add/remove functions taking
a qemu_irq parameter, let's rename existing ones with a gsi suffix.

Signed-off-by: Eric Auger <eric.auger@linaro.org>
Tested-by: Vikram Sethi <vikrams@codeaurora.org>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-07-06 12:15:13 -06:00
Peter Crosthwaite
f7ceed190d vfio: cpu: Use "real" page size API
This is system level code, and should only depend on the host page
size, not the target page size.

Note that HOST_PAGE_SIZE is misleadingly lead and is really aligning
to both host and target page size. Hence it's replacement with
REAL_HOST_PAGE_SIZE.

Signed-off-by: Peter Crosthwaite <crosthwaite.peter@gmail.com>
Tested-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-07-06 12:15:12 -06:00
Paolo Bonzini
7d489dcdf5 vfio: fix return type of pread
size_t is an unsigned type, thus the error case is never reached in
the below call to pread.  If bytes is negative, it will be seen as
a very high positive value.

Spotted by Coverity.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-07-06 12:15:12 -06:00
Alex Williamson
5655f931ab vfio-pci: Reset workaround for AMD Bonaire and Hawaii GPUs
Somehow these GPUs manage not to respond to a PCI bus reset, removing
our primary mechanism for resetting graphics cards.  The result is
that these devices typically work well for a single VM boot.  If the
VM is rebooted or restarted, the guest driver is not able to init the
card from the dirty state, resulting in a blue screen for Windows
guests.

The workaround is to use a device specific reset.  This is not 100%
reliable though since it depends on the incoming state of the device,
but it substantially improves the usability of these devices in a VM.

Credit to Alex Deucher <alexander.deucher@amd.com> for his guidance.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-04-28 11:14:02 -06:00
Alex Williamson
c6d231e2fd vfio-pci: Fix error path sign
This is an impossible error path due to the fact that we're reading a
kernel provided, rather than user provided link, which will certainly
always fit in PATH_MAX.  Currently it returns a fixed 26 char path
plus %d group number, which typically maxes out at double digits.
However, the caller of the initfn certainly expects a less-than zero
return value on error, not just a non-zero value.  Therefore we
should correct the sign here.

Reported-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-04-28 11:14:02 -06:00
Alex Williamson
07ceaf9880 vfio-pci: Further fix BAR size overflow
In an analysis by Laszlo, the resulting type of our calculation for
the end of the MSI-X table, and thus the start of memory after the
table, is uint32_t.  We're therefore not correctly preventing the
corner case overflow that we intended to fix here where a BAR >=4G
could place the MSI-X table to end exactly at the 4G boundary.  The
MSI-X table offset is defined by the hardware spec to 32bits, so we
simply use a cast rather than changing data structure types.  This
scenario is purely theoretically, typically the MSI-X table is located
at the front of the BAR.

Reported-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-04-28 11:14:02 -06:00
Peter Maydell
3b64349539 memory: Replace io_mem_read/write with memory_region_dispatch_read/write
Rather than retaining io_mem_read/write as simple wrappers around
the memory_region_dispatch_read/write functions, make the latter
public and change all the callers to use them, since we need to
touch all the callsites anyway to add MemTxAttrs and MemTxResult
support. Delete io_mem_read and io_mem_write entirely.

(All the callers currently pass MEMTXATTRS_UNSPECIFIED
and convert the return value back to bool or ignore it.)

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
2015-04-26 16:49:23 +01:00
Alex Williamson
47cbe50cc8 vfio-pci: Enable device request notification support
Linux v4.0-rc1 vfio-pci introduced a new virtual interrupt to allow
the kernel to request a device from the user.  When signaled, QEMU
will by default attmempt to hot-unplug the device.  This is a one-
shot attempt with the expectation that the kernel will continue to
poll for the device if it is not returned.  Returning the device when
requested is the expected standard model of cooperative usage, but we
also add an option option to disable this feature.  Initially this
opt-out is set as an experimental option because we really should
honor kernel requests for the device.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-03-02 11:38:55 -07:00
Samuel Pitoiset
6ee47c9008 vfio: allow to disable MMAP per device with -x-mmap=off option
Disabling MMAP support uses the slower read/write accesses but allows to
trace all MMIO accesses, which is not good for performance, but very
useful for reverse engineering PCI drivers. This option allows to
disable MMAP per device without a compile-time change.

Signed-off-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-03-02 11:38:55 -07:00
Alexey Kardashevskiy
bc5baffa35 vfio: Fix debug message compile error
This fixes a compiler error which occurs if DEBUG_VFIO is defined.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-02-10 10:25:44 -07:00
Paolo Bonzini
ba5e6bfa1a vfio: unmap and free BAR data in instance_finalize
In the case of VFIO, the unrealize callback is too early to munmap the
BARs.  The munmap must be delayed until memory accesses are complete.
To do this, split vfio_unmap_bars in two.  The removal step, now called
vfio_unregister_bars, remains in vfio_exitfn.  The reclamation step
is vfio_unmap_bars and is moved to the instance_finalize callback.

Similarly, quirk MemoryRegions have to be removed during
vfio_unregister_bars, but freeing the data structure must be delayed
to vfio_unmap_bars.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-02-10 10:25:44 -07:00
Paolo Bonzini
77a10d04d0 vfio: free dynamically-allocated data in instance_finalize
In order to enable out-of-BQL address space lookup, destruction of
devices needs to be split in two phases.

Unrealize is the first phase; once it complete no new accesses will
be started, but there may still be pending memory accesses can still
be completed.

The second part is freeing the device, which only happens once all memory
accesses are complete.  At this point the reference count has dropped to
zero, an RCU grace period must have completed (because the RCU-protected
FlatViews hold a reference to the device via memory_region_ref).  This is
when instance_finalize is called.

Freeing data belongs in an instance_finalize callback, because the
dynamically allocated memory can still be used after unrealize by the
pending memory accesses.

This starts the process by creating an instance_finalize callback and
freeing most of the dynamically-allocated data in instance_finalize.
Because instance_finalize is also called on error paths or also when
the device is actually not realized, the common code needs some changes
to be ready for this.  The error path in vfio_initfn can be simplified too.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-02-10 10:25:44 -07:00
Paolo Bonzini
217e9fdcad vfio: cleanup vfio_get_device error path, remove vfio_populate_device callback
Now that vfio_put_base_device is called unconditionally at instance_finalize
time, it can be called twice if vfio_populate_device fails.  This works
but it is slightly harder to follow.

Change vfio_get_device to not touch the vbasedev struct until it will
definitely succeed, moving the vfio_populate_device call back to vfio-pci.
This way, vfio_put_base_device will only be called once.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-02-10 10:25:44 -07:00