Commit Graph

60 Commits

Author SHA1 Message Date
Alex Williamson d24cdbfd28 vfio-pci: Avoid deadlock on remove
If an attempt is made to unbind a device from vfio-pci while that
device is in use, the request is blocked until the device becomes
unused.  Unfortunately, that unbind path still grabs the device_lock,
which certain things like __pci_reset_function() also want to take.
This means we need to try to acquire the locks ourselves and use the
pre-locked version, __pci_reset_function_locked().

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2013-07-24 16:36:41 -06:00
Alex Williamson c64019302b vfio: Ignore sprurious notifies
Remove debugging WARN_ON if we get a spurious notify for a group that
no longer exists.  No reports of anyone hitting this, but it would
likely be a race and not a bug if they did.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2013-07-24 16:36:40 -06:00
Alex Williamson de9c7602ca vfio: Don't overreact to DEL_DEVICE
BUS_NOTIFY_DEL_DEVICE triggers IOMMU drivers to remove devices from
their iommu group, but there's really nothing we can do about it at
this point.  If the device is in use, then the vfio sub-driver will
block the device_del from completing until it's released.  If the
device is not in use or not owned by a vfio sub-driver, then we
really don't care that it's being removed.

The current code can be triggered just by unloading an sr-iov driver
(ex. igb) while the VFs are attached to vfio-pci because it makes an
incorrect assumption about the ordering of driver remove callbacks
vs the DEL_DEVICE notification.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2013-07-24 16:36:00 -06:00
Linus Torvalds 15a49b9a90 vfio Updates for v3.11
Largely hugepage support for vfio/type1 iommu and surrounding cleanups and fixes.
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Merge tag 'vfio-v3.11' of git://github.com/awilliam/linux-vfio

Pull vfio updates from Alex Williamson:
 "Largely hugepage support for vfio/type1 iommu and surrounding cleanups
  and fixes"

* tag 'vfio-v3.11' of git://github.com/awilliam/linux-vfio:
  vfio/type1: Fix leak on error path
  vfio: Limit group opens
  vfio/type1: Fix missed frees and zero sized removes
  vfio: fix documentation
  vfio: Provide module option to disable vfio_iommu_type1 hugepage support
  vfio: hugepage support for vfio_iommu_type1
  vfio: Convert type1 iommu to use rbtree
2013-07-10 14:50:08 -07:00
Linus Torvalds 65b97fb730 Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc
Pull powerpc updates from Ben Herrenschmidt:
 "This is the powerpc changes for the 3.11 merge window.  In addition to
  the usual bug fixes and small updates, the main highlights are:

   - Support for transparent huge pages by Aneesh Kumar for 64-bit
     server processors.  This allows the use of 16M pages as transparent
     huge pages on kernels compiled with a 64K base page size.

   - Base VFIO support for KVM on power by Alexey Kardashevskiy

   - Wiring up of our nvram to the pstore infrastructure, including
     putting compressed oopses in there by Aruna Balakrishnaiah

   - Move, rework and improve our "EEH" (basically PCI error handling
     and recovery) infrastructure.  It is no longer specific to pseries
     but is now usable by the new "powernv" platform as well (no
     hypervisor) by Gavin Shan.

   - I fixed some bugs in our math-emu instruction decoding and made it
     usable to emulate some optional FP instructions on processors with
     hard FP that lack them (such as fsqrt on Freescale embedded
     processors).

   - Support for Power8 "Event Based Branch" facility by Michael
     Ellerman.  This facility allows what is basically "userspace
     interrupts" for performance monitor events.

   - A bunch of Transactional Memory vs.  Signals bug fixes and HW
     breakpoint/watchpoint fixes by Michael Neuling.

  And more ...  I appologize in advance if I've failed to highlight
  something that somebody deemed worth it."

* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (156 commits)
  pstore: Add hsize argument in write_buf call of pstore_ftrace_call
  powerpc/fsl: add MPIC timer wakeup support
  powerpc/mpic: create mpic subsystem object
  powerpc/mpic: add global timer support
  powerpc/mpic: add irq_set_wake support
  powerpc/85xx: enable coreint for all the 64bit boards
  powerpc/8xx: Erroneous double irq_eoi() on CPM IRQ in MPC8xx
  powerpc/fsl: Enable CONFIG_E1000E in mpc85xx_smp_defconfig
  powerpc/mpic: Add get_version API both for internal and external use
  powerpc: Handle both new style and old style reserve maps
  powerpc/hw_brk: Fix off by one error when validating DAWR region end
  powerpc/pseries: Support compression of oops text via pstore
  powerpc/pseries: Re-organise the oops compression code
  pstore: Pass header size in the pstore write callback
  powerpc/powernv: Fix iommu initialization again
  powerpc/pseries: Inform the hypervisor we are using EBB regs
  powerpc/perf: Add power8 EBB support
  powerpc/perf: Core EBB support for 64-bit book3s
  powerpc/perf: Drop MMCRA from thread_struct
  powerpc/perf: Don't enable if we have zero events
  ...
2013-07-04 10:29:23 -07:00
Alex Williamson 8d38ef1948 vfio/type1: Fix leak on error path
We also don't handle unpinning zero pages as an error on other exits
so we can fix that inconsistency by rolling in the next conditional
return.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2013-07-01 08:28:58 -06:00
Al Viro a47df1518e vfio: remap_pfn_range() sets all those flags...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-06-29 12:46:41 +04:00
Alex Williamson 6d6768c61b vfio: Limit group opens
vfio_group_fops_open attempts to limit concurrent sessions by
disallowing opens once group->container is set.  This really doesn't
do what we want and allow for inconsistent behavior, for instance a
group can be opened twice, then a container set giving the user two
file descriptors to the group.  But then it won't allow more to be
opened.  There's not much reason to have the group opened multiple
times since most access is through devices or the container, so
complete what the original code intended and only allow a single
instance.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2013-06-25 16:06:54 -06:00
Alex Williamson f5bfdbf252 vfio/type1: Fix missed frees and zero sized removes
With hugepage support we can only properly aligned and sized ranges.
We only guarantee that we can unmap the same ranges mapped and not
arbitrary sub-ranges.  This means we might not free anything or might
free more than requested.  The vfio unmap interface started storing
the unmapped size to return to userspace to handle this.  This patch
fixes a few places where we don't properly handle those cases, moves
a memory allocation to a place where failure is an option and checks
our loops to make sure we don't get into an infinite loop trying to
remove an overlap.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2013-06-25 16:01:44 -06:00
Alex Williamson 5c6c2b21ec vfio: Provide module option to disable vfio_iommu_type1 hugepage support
Add a module option to vfio_iommu_type1 to disable IOMMU hugepage
support.  This causes iommu_map to only be called with single page
mappings, disabling the IOMMU driver's ability to use hugepages.
This option can be enabled by loading vfio_iommu_type1 with
disable_hugepages=1 or dynamically through sysfs.  If enabled
dynamically, only new mappings are restricted.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2013-06-21 09:38:11 -06:00
Alex Williamson 166fd7d94a vfio: hugepage support for vfio_iommu_type1
We currently send all mappings to the iommu in PAGE_SIZE chunks,
which prevents the iommu from enabling support for larger page sizes.
We still need to pin pages, which means we step through them in
PAGE_SIZE chunks, but we can batch up contiguous physical memory
chunks to allow the iommu the opportunity to use larger pages.  The
approach here is a bit different that the one currently used for
legacy KVM device assignment.  Rather than looking at the vma page
size and using that as the maximum size to pass to the iommu, we
instead simply look at whether the next page is physically
contiguous.  This means we might ask the iommu to map a 4MB region,
while legacy KVM might limit itself to a maximum of 2MB.

Splitting our mapping path also allows us to be smarter about locked
memory because we can more easily unwind if the user attempts to
exceed the limit.  Therefore, rather than assuming that a mapping
will result in locked memory, we test each page as it is pinned to
determine whether it locks RAM vs an mmap'd MMIO region.  This should
result in better locking granularity and less locked page fudge
factors in userspace.

The unmap path uses the same algorithm as legacy KVM.  We don't want
to track the pfn for each mapping ourselves, but we need the pfn in
order to unpin pages.  We therefore ask the iommu for the iova to
physical address translation, ask it to unpin a page, and see how many
pages were actually unpinned.  iommus supporting large pages will
often return something bigger than a page here, which we know will be
physically contiguous and we can unpin a batch of pfns.  iommus not
supporting large mappings won't see an improvement in batching here as
they only unmap a page at a time.

With this change, we also make a clarification to the API for mapping
and unmapping DMA.  We can only guarantee unmaps at the same
granularity as used for the original mapping.  In other words,
unmapping a subregion of a previous mapping is not guaranteed and may
result in a larger or smaller unmapping than requested.  The size
field in the unmapping structure is updated to reflect this.
Previously this was unmodified on mapping, always returning the the
requested unmap size.  This is now updated to return the actual unmap
size on success, allowing userspace to appropriately track mappings.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2013-06-21 09:38:02 -06:00
Alex Williamson cd9b22685e vfio: Convert type1 iommu to use rbtree
We need to keep track of all the DMA mappings of an iommu container so
that it can be automatically unmapped when the user releases the file
descriptor.  We currently do this using a simple list, where we merge
entries with contiguous iovas and virtual addresses.  Using a tree for
this is a bit more efficient and allows us to use common code instead
of inventing our own.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2013-06-21 09:37:50 -06:00
Alexey Kardashevskiy 5b25199eff powerpc/vfio: Enable on pSeries platform
The enables VFIO on the pSeries platform, enabling user space
programs to access PCI devices directly.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Cc: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-06-20 16:55:15 +10:00
Alexey Kardashevskiy 5ffd229c02 powerpc/vfio: Implement IOMMU driver for VFIO
VFIO implements platform independent stuff such as
a PCI driver, BAR access (via read/write on a file descriptor
or direct mapping when possible) and IRQ signaling.

The platform dependent part includes IOMMU initialization
and handling.  This implements an IOMMU driver for VFIO
which does mapping/unmapping pages for the guest IO and
provides information about DMA window (required by a POWER
guest).

Cc: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-06-20 16:55:14 +10:00
Alexey Kardashevskiy 9a6aa279d3 vfio: fix crash on rmmod
devtmpfs_delete_node() calls devnode() callback with mode==NULL but
vfio still tries to write there.

The patch fixes this.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2013-06-05 08:54:16 -06:00
Linus Torvalds 0b2e3b6bb4 vfio updates for v3.10
Changes include extension to support PCI AER notification to userspace, byte granularity of PCI config space and access to unarchitected PCI config space, better protection around IOMMU driver accesses, default file mode fix, and a few misc cleanups.
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Merge tag 'vfio-for-v3.10' of git://github.com/awilliam/linux-vfio

Pull vfio updates from Alex Williamson:
 "Changes include extension to support PCI AER notification to
  userspace, byte granularity of PCI config space and access to
  unarchitected PCI config space, better protection around IOMMU driver
  accesses, default file mode fix, and a few misc cleanups."

* tag 'vfio-for-v3.10' of git://github.com/awilliam/linux-vfio:
  vfio: Set container device mode
  vfio: Use down_reads to protect iommu disconnects
  vfio: Convert container->group_lock to rwsem
  PCI/VFIO: use pcie_flags_reg instead of access PCI-E Capabilities Register
  vfio-pci: Enable raw access to unassigned config space
  vfio-pci: Use byte granularity in config map
  vfio: make local function vfio_pci_intx_unmask_handler() static
  VFIO-AER: Vfio-pci driver changes for supporting AER
  VFIO: Wrapper for getting reference to vfio_device
2013-05-02 14:02:32 -07:00
Alex Williamson 664e9386bd vfio: Set container device mode
Minor 0 is the VFIO container device (/dev/vfio/vfio).  On it's own
the container does not provide a user with any privileged access.  It
only supports API version check and extension check ioctls.  Only by
attaching a VFIO group to the container does it gain any access.  Set
the mode of the container to allow access.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2013-04-30 15:42:28 -06:00
Linus Torvalds 96a3e8af5a PCI changes for the v3.10 merge window:
PCI device hotplug
     - Remove ACPI PCI subdrivers (Jiang Liu, Myron Stowe)
     - Make acpiphp builtin only, not modular (Jiang Liu)
     - Add acpiphp mutual exclusion (Jiang Liu)
 
   Power management
     - Skip "PME enabled/disabled" messages when not supported (Rafael Wysocki)
     - Fix fallback to PCI_D0 (Rafael Wysocki)
 
   Miscellaneous
     - Factor quirk_io_region (Yinghai Lu)
     - Cache MSI capability offsets & cleanup (Gavin Shan, Bjorn Helgaas)
     - Clean up EISA resource initialization and logging (Bjorn Helgaas)
     - Fix prototype warnings (Andy Shevchenko, Bjorn Helgaas)
     - MIPS: Initialize of_node before scanning bus (Gabor Juhos)
     - Fix pcibios_get_phb_of_node() declaration "weak" annotation (Gabor Juhos)
     - Add MSI INTX_DISABLE quirks for AR8161/AR8162/etc (Xiong Huang)
     - Fix aer_inject return values (Prarit Bhargava)
     - Remove PME/ACPI dependency (Andrew Murray)
     - Use shared PCI_BUS_NUM() and PCI_DEVID() (Shuah Khan)
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Merge tag 'pci-v3.10-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci

Pull PCI updates from Bjorn Helgaas:
 "PCI changes for the v3.10 merge window:

  PCI device hotplug
   - Remove ACPI PCI subdrivers (Jiang Liu, Myron Stowe)
   - Make acpiphp builtin only, not modular (Jiang Liu)
   - Add acpiphp mutual exclusion (Jiang Liu)

  Power management
   - Skip "PME enabled/disabled" messages when not supported (Rafael
     Wysocki)
   - Fix fallback to PCI_D0 (Rafael Wysocki)

  Miscellaneous
   - Factor quirk_io_region (Yinghai Lu)
   - Cache MSI capability offsets & cleanup (Gavin Shan, Bjorn Helgaas)
   - Clean up EISA resource initialization and logging (Bjorn Helgaas)
   - Fix prototype warnings (Andy Shevchenko, Bjorn Helgaas)
   - MIPS: Initialize of_node before scanning bus (Gabor Juhos)
   - Fix pcibios_get_phb_of_node() declaration "weak" annotation (Gabor
     Juhos)
   - Add MSI INTX_DISABLE quirks for AR8161/AR8162/etc (Xiong Huang)
   - Fix aer_inject return values (Prarit Bhargava)
   - Remove PME/ACPI dependency (Andrew Murray)
   - Use shared PCI_BUS_NUM() and PCI_DEVID() (Shuah Khan)"

* tag 'pci-v3.10-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (63 commits)
  vfio-pci: Use cached MSI/MSI-X capabilities
  vfio-pci: Use PCI_MSIX_TABLE_BIR, not PCI_MSIX_FLAGS_BIRMASK
  PCI: Remove "extern" from function declarations
  PCI: Use PCI_MSIX_TABLE_BIR, not PCI_MSIX_FLAGS_BIRMASK
  PCI: Drop msi_mask_reg() and remove drivers/pci/msi.h
  PCI: Use msix_table_size() directly, drop multi_msix_capable()
  PCI: Drop msix_table_offset_reg() and msix_pba_offset_reg() macros
  PCI: Drop is_64bit_address() and is_mask_bit_support() macros
  PCI: Drop msi_data_reg() macro
  PCI: Drop msi_lower_address_reg() and msi_upper_address_reg() macros
  PCI: Drop msi_control_reg() macro and use PCI_MSI_FLAGS directly
  PCI: Use cached MSI/MSI-X offsets from dev, not from msi_desc
  PCI: Clean up MSI/MSI-X capability #defines
  PCI: Use cached MSI-X cap while enabling MSI-X
  PCI: Use cached MSI cap while enabling MSI interrupts
  PCI: Remove MSI/MSI-X cap check in pci_msi_check_device()
  PCI: Cache MSI/MSI-X capability offsets in struct pci_dev
  PCI: Use u8, not int, for PM capability offset
  [SCSI] megaraid_sas: Use correct #define for MSI-X capability
  PCI: Remove "extern" from function declarations
  ...
2013-04-29 09:30:25 -07:00
Alex Williamson 0b43c08233 vfio: Use down_reads to protect iommu disconnects
If a group or device is released or a container is unset from a group
it can race against file ops on the container.  Protect these with
down_reads to allow concurrent users.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Reported-by: Michael S. Tsirkin <mst@redhat.com>
2013-04-29 08:41:36 -06:00
Alex Williamson 9587f44aa6 vfio: Convert container->group_lock to rwsem
All current users are writers, maintaining current mutual exclusion.
This lets us add read users next.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2013-04-25 16:12:38 -06:00
Bjorn Helgaas a9047f24df vfio-pci: Use cached MSI/MSI-X capabilities
We now cache the MSI/MSI-X capability offsets in the struct pci_dev,
so no need to find the capabilities again.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
2013-04-24 11:35:56 -06:00
Bjorn Helgaas 508d1aa602 vfio-pci: Use PCI_MSIX_TABLE_BIR, not PCI_MSIX_FLAGS_BIRMASK
PCI_MSIX_FLAGS_BIRMASK is mis-named because the BIR mask is in the
Table Offset register, not the flags ("Message Control" per spec)
register.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
2013-04-24 11:35:56 -06:00
Yijing Wang aa2cba51a0 PCI/VFIO: use pcie_flags_reg instead of access PCI-E Capabilities Register
Currently, we use pcie_flags_reg to cache PCI-E Capabilities Register,
because PCI-E Capabilities Register bits are almost read-only. This patch
use pcie_caps_reg() instead of another access PCI-E Capabilities Register.

Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2013-04-15 08:45:10 -06:00
Alex Williamson a7d1ea1c11 vfio-pci: Enable raw access to unassigned config space
Devices like be2net hide registers between the gaps in capabilities
and architected regions of PCI config space.  Our choices to support
such devices is to either build an ever growing and unmanageable white
list or rely on hardware isolation to protect us.  These registers are
really no different than MMIO or I/O port space registers, which we
don't attempt to regulate, so treat PCI config space in the same way.

Reported-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Tested-by: Gavin Shan <shangw@linux.vnet.ibm.com>
2013-04-01 09:04:12 -06:00
Alex Williamson 180b138107 vfio-pci: Use byte granularity in config map
The config map previously used a byte per dword to map regions of
config space to capabilities.  Modulo a bug where we round the length
of capabilities down instead of up, this theoretically works well and
saves space so long as devices don't try to hide registers in the gaps
between capabilities.  Unfortunately they do exactly that so we need
byte granularity on our config space map.  Increase the allocation of
the config map and split accesses at capability region boundaries.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Tested-by: Gavin Shan <shangw@linux.vnet.ibm.com>
2013-04-01 09:03:44 -06:00
Alex Williamson 904c680c7b vfio-pci: Fix possible integer overflow
The VFIO_DEVICE_SET_IRQS ioctl takes a start and count parameter, both
of which are unsigned.  We attempt to bounds check these, but fail to
account for the case where start is a very large number, allowing
start + count to wrap back into the valid range.  Bounds check both
start and start + count.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2013-03-26 11:33:16 -06:00
Wei Yongjun 0bced2f728 vfio: make local function vfio_pci_intx_unmask_handler() static
vfio_pci_intx_unmask_handler() was not declared. It should be static.

Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2013-03-25 11:15:44 -06:00
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
Vijay Mohan Pandarathil dad9f8972e VFIO-AER: Vfio-pci driver changes for supporting AER
- New VFIO_SET_IRQ ioctl option to pass the eventfd that is signaled when
  an error occurs in the vfio_pci_device

- Register pci_error_handler for the vfio_pci driver

- When the device encounters an error, the error handler registered by
  the vfio_pci driver gets invoked by the AER infrastructure

- In the error handler, signal the eventfd registered for the device.

- This results in the qemu eventfd handler getting invoked and
  appropriate action taken for the guest.

Signed-off-by: Vijay Mohan Pandarathil <vijaymohan.pandarathil@hp.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2013-03-11 09:31:22 -06:00
Vijay Mohan Pandarathil 44f507163d VFIO: Wrapper for getting reference to vfio_device
- Added vfio_device_get_from_dev() as wrapper to get
  reference to vfio_device from struct device.

- Added vfio_device_data() as a wrapper to get device_data from
  vfio_device.

Signed-off-by: Vijay Mohan Pandarathil <vijaymohan.pandarathil@hp.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2013-03-11 09:28:44 -06:00
Tejun Heo a1c36b166b vfio: convert to idr_alloc()
Convert to the much saner new idr interface.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-27 19:10:19 -08:00
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 2b489a45f6 vfio: whitelist pcieport
pcieport does nice things like manage AER and we know it doesn't do
DMA or expose any user accessible devices on the host.  It also keeps
the Memory, I/O, and Busmaster bits enabled, which is pretty handy
when trying to use anyting below it.  Devices owned by pcieport cannot
be given to users via vfio, but we can tolerate them not being owned
by vfio-pci.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2013-02-14 14:02:13 -07:00
Alex Williamson e014e9444a vfio: Protect vfio_dev_present against device_del
vfio_dev_present is meant to give us a wait_event callback so that we
can block removing a device from vfio until it becomes unused.  The
root of this check depends on being able to get the iommu group from
the device.  Unfortunately if the BUS_NOTIFY_DEL_DEVICE notifier has
fired then the device-group reference is no longer searchable and we
fail the lookup.

We don't need to go to such extents for this though.  We have a
reference to the device, from which we can acquire a reference to the
group.  We can then use the group reference to search for the device
and properly block removal.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2013-02-14 14:02:13 -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
Jiang Liu de2b3eeafb VFIO: use ACCESS_ONCE() to guard access to dev->driver
Comments from dev_driver_string(),
/* dev->driver can change to NULL underneath us because of unbinding,
 * so be careful about accessing it.
 */

So use ACCESS_ONCE() to guard access to dev->driver field.

Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2012-12-07 13:43:50 -07:00
Jiang Liu 9df7b25ab7 VFIO: unregister IOMMU notifier on error recovery path
On error recovery path in function vfio_create_group(), it should
unregister the IOMMU notifier for the new VFIO group. Otherwise it may
cause invalid memory access later when handling bus notifications.

Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2012-12-07 13:43:50 -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