linux-toradex.git/drivers/vfio, branch v4.6-rc2

Merge tag 'vfio-v4.6-rc1' of git://github.com/awilliam/linux-vfio

2016-03-17T20:05:09+00:00

Pull VFIO updates from Alex Williamson:
 "Various enablers for assignment of Intel graphics devices and future
  support of vGPU devices (Alex Williamson).  This includes

   - Handling the vfio type1 interface as an API rather than a specific
     implementation, allowing multiple type1 providers.

   - Capability chains, similar to PCI device capabilities, that allow
     extending ioctls.  Extensions here include device specific regions
     and sparse mmap descriptions.  The former is used to expose non-PCI
     regions for IGD, including the OpRegion (particularly the Video
     BIOS Table), and read only PCI config access to the host and LPC
     bridge as drivers often depend on identifying those devices.

     Sparse mmaps here are used to describe the MSIx vector table, which
     vfio has always protected from mmap, but never had an API to
     explicitly define that protection.  In future vGPU support this is
     expected to allow the description of PCI BARs that may mix direct
     access and emulated access within a single region.

   - The ability to expose the shadow ROM as an option ROM as IGD use
     cases may rely on the ROM even though the physical device does not
     make use of a PCI option ROM BAR"

* tag 'vfio-v4.6-rc1' of git://github.com/awilliam/linux-vfio:
  vfio/pci: return -EFAULT if copy_to_user fails
  vfio/pci: Expose shadow ROM as PCI option ROM
  vfio/pci: Intel IGD host and LCP bridge config space access
  vfio/pci: Intel IGD OpRegion support
  vfio/pci: Enable virtual register in PCI config space
  vfio/pci: Add infrastructure for additional device specific regions
  vfio: Define device specific region type capability
  vfio/pci: Include sparse mmap capability for MSI-X table regions
  vfio: Define sparse mmap capability for regions
  vfio: Add capability chain helpers
  vfio: Define capability chains
  vfio: If an IOMMU backend fails, keep looking
  vfio/pci: Fix unsigned comparison overflow

vfio: fix ioctl error handling

2016-02-28T14:38:52+00:00

Calling return copy_to_user(...) in an ioctl will not
do the right thing if there's a pagefault:
copy_to_user returns the number of bytes not copied
in this case.

Fix up vfio to do
	return copy_to_user(...)) ?
		-EFAULT : 0;

everywhere.

Cc: stable@vger.kernel.org
Signed-off-by: Michael S. Tsirkin 
Signed-off-by: Alex Williamson

vfio/pci: return -EFAULT if copy_to_user fails

2016-02-26T04:48:42+00:00

The copy_to_user() function returns the number of bytes that were not
copied but we want to return -EFAULT on error here.

Fixes: 188ad9d6cbbc ('vfio/pci: Include sparse mmap capability for MSI-X table regions')
Signed-off-by: Dan Carpenter 
Signed-off-by: Alex Williamson

vfio/pci: Expose shadow ROM as PCI option ROM

2016-02-22T23:10:09+00:00

Integrated graphics may have their ROM shadowed at 0xc0000 rather than
implement a PCI option ROM.  Make this ROM appear to the user using
the ROM BAR.

Signed-off-by: Alex Williamson

vfio/pci: Intel IGD host and LCP bridge config space access

2016-02-22T23:10:09+00:00

Provide read-only access to PCI config space of the PCI host bridge
and LPC bridge through device specific regions.  This may be used to
configure a VM with matching register contents to satisfy driver
requirements.  Providing this through the vfio file descriptor removes
an additional userspace requirement for access through pci-sysfs and
removes the CAP_SYS_ADMIN requirement that doesn't appear to apply to
the specific devices we're accessing.

Signed-off-by: Alex Williamson

vfio/pci: Intel IGD OpRegion support

2016-02-22T23:10:09+00:00

This is the first consumer of vfio device specific resource support,
providing read-only access to the OpRegion for Intel graphics devices.

Signed-off-by: Alex Williamson

vfio/pci: Enable virtual register in PCI config space

2016-02-22T23:10:09+00:00

Typically config space for a device is mapped out into capability
specific handlers and unassigned space.  The latter allows direct
read/write access to config space.  Sometimes we know about registers
living in this void space and would like an easy way to virtualize
them, similar to how BAR registers are managed.  To do this, create
one more pseudo (fake) PCI capability to be handled as purely virtual
space.  Reads and writes are serviced entirely from virtual config
space.

Signed-off-by: Alex Williamson

vfio/pci: Add infrastructure for additional device specific regions

2016-02-22T23:10:09+00:00

Add support for additional regions with indexes started after the
already defined fixed regions.  Device specific code can register
these regions with the new vfio_pci_register_dev_region() function.
The ops structure per region currently only includes read/write
access and a release function, allowing automatic cleanup when the
device is closed.  mmap support is only missing here because it's
not needed by the first user queued for this support.

Signed-off-by: Alex Williamson

vfio/pci: Include sparse mmap capability for MSI-X table regions

2016-02-22T23:10:09+00:00

vfio-pci has never allowed the user to directly mmap the MSI-X vector
table, but we've always relied on implicit knowledge of the user that
they cannot do this.  Now that we have capability chains that we can
expose in the region info ioctl and a sparse mmap capability that
represents the sub-areas within the region that can be mmap'd, we can
make the mmap constraints more explicit.

Signed-off-by: Alex Williamson

vfio: Add capability chain helpers

2016-02-22T23:10:08+00:00

Allow sub-modules to easily reallocate a buffer for managing
capability chains for info ioctls.

Signed-off-by: Alex Williamson