Commit Graph

18 Commits

Author SHA1 Message Date
Arnd Bergmann 25e9789ddd vfio: include <linux/slab.h> for kmalloc
The vfio drivers call kmalloc or kzalloc, but do not
include <linux/slab.h>, which causes build errors on
ARM.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Cc: kvm@vger.kernel.org
2013-03-15 12:58:20 -06:00
Kees Cook d65530fbc7 drivers/vfio: remove depends on CONFIG_EXPERIMENTAL
The CONFIG_EXPERIMENTAL config item has not carried much meaning for a
while now and is almost always enabled by default. As agreed during the
Linux kernel summit, remove it from any "depends on" lines in Kconfigs.

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2013-02-24 09:59:44 -07:00
Alex Williamson 84237a826b vfio-pci: Add support for VGA region access
PCI defines display class VGA regions at I/O port address 0x3b0, 0x3c0
and MMIO address 0xa0000.  As these are non-overlapping, we can ignore
the I/O port vs MMIO difference and expose them both in a single
region.  We make use of the VGA arbiter around each access to
configure chipset access as necessary.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2013-02-18 10:11:13 -07:00
Alex Williamson 2dd1194833 vfio-pci: Manage user power state transitions
We give the user access to change the power state of the device but
certain transitions result in an uninitialized state which the user
cannot resolve.  To fix this we need to mark the PowerState field of
the PMCSR register read-only and effect the requested change on behalf
of the user.  This has the added benefit that pdev->current_state
remains accurate while controlled by the user.

The primary example of this bug is a QEMU guest doing a reboot where
the device it put into D3 on shutdown and becomes unusable on the next
boot because the device did a soft reset on D3->D0 (NoSoftRst-).

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2013-02-18 10:10:33 -07:00
Alex Williamson 906ee99dd2 vfio-pci: Cleanup BAR access
We can actually handle MMIO and I/O port from the same access function
since PCI already does abstraction of this.  The ROM BAR only requires
a minor difference, so it gets included too.  vfio_pci_config_readwrite
gets renamed for consistency.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2013-02-14 14:02:12 -07:00
Alex Williamson 5b279a11d3 vfio-pci: Cleanup read/write functions
The read and write functions are nearly identical, combine them
and convert to a switch statement.  This also makes it easy to
narrow the scope of when we use the io/mem accessors in case new
regions are added.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2013-02-14 14:02:12 -07:00
Alex Williamson 5641ade41f vfio-pci: Enable PCIe extended capabilities on v1
Even PCIe 1.x had extended config space.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2013-02-14 10:45:31 -07:00
Alex Williamson ec1287e511 vfio-pci: Fix buffer overfill
A read from a range hidden from the user (ex. MSI-X vector table)
attempts to fill the user buffer up to the end of the excluded range
instead of up to the requested count.  Fix it.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Cc: stable@vger.kernel.org
2013-01-15 10:45:26 -07:00
Alex Williamson 9a92c5091a vfio-pci: Enable device before attempting reset
Devices making use of PM reset are getting incorrectly identified as
not supporting reset because pci_pm_reset() fails unless the device is
in D0 power state.  When first attached to vfio_pci devices are
typically in an unknown power state.  We can fix this by explicitly
setting the power state or simply calling pci_enable_device() before
attempting a pci_reset_function().  We need to enable the device
anyway, so move this up in our vfio_pci_enable() function, which also
simplifies the error path a bit.

Note that pci_disable_device() does not explicitly set the power
state, so there's no need to re-order vfio_pci_disable().

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2012-12-07 13:43:51 -07:00
Jiang Liu 05bf3aac93 VFIO: fix out of order labels for error recovery in vfio_pci_init()
The two labels for error recovery in function vfio_pci_init() is out of
order, so fix it.

Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2012-12-07 13:43:51 -07:00
Alex Williamson 2007722a60 vfio-pci: Re-order device reset
Move the device reset to the end of our disable path, the device
should already be stopped from pci_disable_device().  This also allows
us to manipulate the save/restore to avoid the save/reset/restore +
save/restore that we had before.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2012-12-07 13:43:50 -07:00
Fengguang Wu 3a1f7041dd vfio: simplify kmalloc+copy_from_user to memdup_user
Generated by: coccinelle/api/memdup_user.cocci

Acked-by: Julia Lawall <julia.lawall@lip6.fr>
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2012-12-07 13:43:49 -07:00
Alex Williamson 899649b7d4 vfio: Fix PCI INTx disable consistency
The virq_disabled flag tracks the userspace view of INTx masking
across interrupt mode changes, but we're not consistently applying
this to the interrupt and masking handler notion of the device.
Currently if the user sets DisINTx while in MSI or MSIX mode, then
returns to INTx mode (ex. rebooting a qemu guest), the hardware has
DisINTx+, but the management of INTx thinks it's enabled, making it
impossible to actually clear DisINTx.  Fix this by updating the
handler state when INTx is re-enabled.

Cc: stable@vger.kernel.org
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2012-10-10 09:10:32 -06:00
Alex Williamson 9dbdfd23b7 vfio: Move PCI INTx eventfd setting earlier
We need to be ready to recieve an interrupt as soon as we call
request_irq, so our eventfd context setting needs to be moved
earlier.  Without this, an interrupt from our device or one
sharing the interrupt line can pass a NULL into eventfd_signal
and oops.

Cc: stable@vger.kernel.org
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2012-10-10 09:10:32 -06:00
Alex Williamson 34002f54d2 vfio: Fix PCI mmap after b3b9c293
Our mmap path mistakely relied on vma->vm_pgoff to get set in
remap_pfn_range.  After b3b9c293, that path only applies to
copy-on-write mappings.  Set it in our own code.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2012-10-10 09:10:31 -06:00
Linus Torvalds 547b1e81af Fix staging driver use of VM_RESERVED
The VM_RESERVED flag was killed off in commit 314e51b985 ("mm: kill
vma flag VM_RESERVED and mm->reserved_vm counter"), and replaced by the
proper semantic flags (eg "don't core-dump" etc).  But there was a new
use of VM_RESERVED that got missed by the merge.

Fix the remaining use of VM_RESERVED in the vfio_pci driver, replacing
the VM_RESERVED flag with VM_DONTEXPAND | VM_DONTDUMP.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation,org>
2012-10-09 21:06:41 +09:00
Alex Williamson b68e7fa879 vfio: Fix virqfd release race
vfoi-pci supports a mechanism like KVM's irqfd for unmasking an
interrupt through an eventfd.  There are two ways to shutdown this
interface: 1) close the eventfd, 2) ioctl (such as disabling the
interrupt).  Both of these do the release through a workqueue,
which can result in a segfault if two jobs get queued for the same
virqfd.

Fix this by protecting the pointer to these virqfds by a spinlock.
The vfio pci device will therefore no longer have a reference to it
once the release job is queued under lock.  On the ioctl side, we
still flush the workqueue to ensure that any outstanding releases
are completed.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2012-09-21 10:48:28 -06:00
Alex Williamson 89e1f7d4c6 vfio: Add PCI device driver
Add PCI device support for VFIO.  PCI devices expose regions
for accessing config space, I/O port space, and MMIO areas
of the device.  PCI config access is virtualized in the kernel,
allowing us to ensure the integrity of the system, by preventing
various accesses while reducing duplicate support across various
userspace drivers.  I/O port supports read/write access while
MMIO also supports mmap of sufficiently sized regions.  Support
for INTx, MSI, and MSI-X interrupts are provided using eventfds to
userspace.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2012-07-31 08:16:24 -06:00