Commit Graph

117 Commits

Author SHA1 Message Date
Alexey Kardashevskiy ec76f40070 vfio-pci: Add missing break to enable VFIO_PCI_ERR_IRQ_INDEX
This adds a missing break statement to VFIO_DEVICE_SET_IRQS handler
without which vfio_pci_set_err_trigger() would never be called.

While we are here, add another "break" to VFIO_PCI_REQ_IRQ_INDEX case
so if we add more indexes later, we won't miss it.

Fixes: 6140a8f562 ("vfio-pci: Add device request interface")
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-03-12 09:51:38 -06:00
Alex Williamson 6140a8f562 vfio-pci: Add device request interface
Userspace can opt to receive a device request notification,
indicating that the device should be released.  This is setup
the same way as the error IRQ and also supports eventfd signaling.
Future support may forcefully remove the device from the user if
the request is ignored.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-02-10 12:38:14 -07:00
Alex Williamson cac80d6e38 vfio-pci: Generalize setup of simple eventfds
We want another single vector IRQ index to support signaling of
the device request to userspace.  Generalize the error reporting
IRQ index to avoid code duplication.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-02-10 12:37:57 -07:00
Alex Williamson 13060b64b8 vfio: Add and use device request op for vfio bus drivers
When a request is made to unbind a device from a vfio bus driver,
we need to wait for the device to become unused, ie. for userspace
to release the device.  However, we have a long standing TODO in
the code to do something proactive to make that happen.  To enable
this, we add a request callback on the vfio bus driver struct,
which is intended to signal the user through the vfio device
interface to release the device.  Instead of passively waiting for
the device to become unused, we can now pester the user to give
it up.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-02-10 12:37:47 -07:00
Alex Williamson 4a68810dbb vfio: Tie IOMMU group reference to vfio group
Move the iommu_group reference from the device to the vfio_group.
This ensures that the iommu_group persists as long as the vfio_group
remains.  This can be important if all of the device from an
iommu_group are removed, but we still have an outstanding vfio_group
reference; we can still walk the empty list of devices.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-02-06 15:05:06 -07:00
Alex Williamson 60720a0fc6 vfio: Add device tracking during unbind
There's a small window between the vfio bus driver calling
vfio_del_group_dev() and the device being completely unbound where
the vfio group appears to be non-viable.  This creates a race for
users like QEMU/KVM where the kvm-vfio module tries to get an
external reference to the group in order to match and release an
existing reference, while the device is potentially being removed
from the vfio bus driver.  If the group is momentarily non-viable,
kvm-vfio may not be able to release the group reference until VM
shutdown, making the group unusable until that point.

Bridge the gap between device removal from the group and completion
of the driver unbind by tracking it in a list.  The device is added
to the list before the bus driver reference is released and removed
using the existing unbind notifier.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-02-06 15:05:06 -07:00
Alex Williamson c5e6688752 vfio/type1: Add conditional rescheduling
IOMMU operations can be expensive and it's not very difficult for a
user to give us a lot of work to do for a map or unmap operation.
Killing a large VM will vfio assigned devices can result in soft
lockups and IOMMU tracing shows that we can easily spend 80% of our
time with need-resched set.  A sprinkling of conf_resched() calls
after map and unmap calls has a very tiny affect on performance
while resulting in traces with <1% of calls overflowing into needs-
resched.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-02-06 14:19:12 -07:00
Alex Williamson babbf17609 vfio/type1: Chunk contiguous reserved/invalid page mappings
We currently map invalid and reserved pages, such as often occur from
mapping MMIO regions of a VM through the IOMMU, using single pages.
There's really no reason we can't instead follow the methodology we
use for normal pages and find the largest possible physically
contiguous chunk for mapping.  The only difference is that we don't
do locked memory accounting for these since they're not back by RAM.

In most applications this will be a very minor improvement, but when
graphics and GPGPU devices are in play, MMIO BARs become non-trivial.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-02-06 10:59:16 -07:00
Alex Williamson 6fe1010d6d vfio/type1: DMA unmap chunking
When unmapping DMA entries we try to rely on the IOMMU API behavior
that allows the IOMMU to unmap a larger area than requested, up to
the size of the original mapping.  This works great when the IOMMU
supports superpages *and* they're in use.  Otherwise, each PAGE_SIZE
increment is unmapped separately, resulting in poor performance.

Instead we can use the IOVA-to-physical-address translation provided
by the IOMMU API and unmap using the largest contiguous physical
memory chunk available, which is also how vfio/type1 would have
mapped the region.  For a synthetic 1TB guest VM mapping and shutdown
test on Intel VT-d (2M IOMMU pagesize support), this achieves about
a 30% overall improvement mapping standard 4K pages, regardless of
IOMMU superpage enabling, and about a 40% improvement mapping 2M
hugetlbfs pages when IOMMU superpages are not available.  Hugetlbfs
with IOMMU superpages enabled is effectively unchanged.

Unfortunately the same algorithm does not work well on IOMMUs with
fine-grained superpages, like AMD-Vi, costing about 25% extra since
the IOMMU will automatically unmap any power-of-two contiguous
mapping we've provided it.  We add a routine and a domain flag to
detect this feature, leaving AMD-Vi unaffected by this unmap
optimization.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2015-02-06 10:58:56 -07:00
Wei Yang 7c2e211f3c vfio-pci: Fix the check on pci device type in vfio_pci_probe()
Current vfio-pci just supports normal pci device, so vfio_pci_probe() will
return if the pci device is not a normal device. While current code makes a
mistake. PCI_HEADER_TYPE is the offset in configuration space of the device
type, but we use this value to mask the type value.

This patch fixs this by do the check directly on the pci_dev->hdr_type.

Signed-off-by: Wei Yang <weiyang@linux.vnet.ibm.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Cc: stable@vger.kernel.org # v3.6+
2015-01-07 10:29:11 -07:00
Linus Torvalds cc669743a3 Merge tag 'vfio-v3.19-rc1' of git://github.com/awilliam/linux-vfio
Pull VFIO updates from Alex Williamson:
 - s390 support (Frank Blaschka)
 - Enable iommu-type1 for ARM SMMU (Will Deacon)

* tag 'vfio-v3.19-rc1' of git://github.com/awilliam/linux-vfio:
  drivers/vfio: allow type-1 IOMMU instantiation on top of an ARM SMMU
  vfio: make vfio run on s390
2014-12-17 10:44:22 -08:00
Jiang Liu 83a18912b0 PCI/MSI: Rename write_msi_msg() to pci_write_msi_msg()
Rename write_msi_msg() to pci_write_msi_msg() to mark it as PCI
specific.

Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Yingjoe Chen <yingjoe.chen@mediatek.com>
Cc: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-11-23 13:01:45 +01:00
Will Deacon 5e9f36c59a drivers/vfio: allow type-1 IOMMU instantiation on top of an ARM SMMU
The ARM SMMU driver is compatible with the notion of a type-1 IOMMU in
VFIO.

This patch allows VFIO_IOMMU_TYPE1 to be selected if ARM_SMMU=y.

Signed-off-by: Will Deacon <will.deacon@arm.com>
[aw: update for existing S390 patch]
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2014-11-14 09:10:59 -07:00
Frank Blaschka 1d53a3a7d3 vfio: make vfio run on s390
add Kconfig switch to hide INTx
add Kconfig switch to let vfio announce PCI BARs are not mapable

Signed-off-by: Frank Blaschka <frank.blaschka@de.ibm.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2014-11-07 09:52:22 -07:00
Linus Torvalds 23971bdfff Merge tag 'iommu-updates-v3.18' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu
Pull IOMMU updates from Joerg Roedel:
 "This pull-request includes:

   - change in the IOMMU-API to convert the former iommu_domain_capable
     function to just iommu_capable

   - various fixes in handling RMRR ranges for the VT-d driver (one fix
     requires a device driver core change which was acked by Greg KH)

   - the AMD IOMMU driver now assigns and deassigns complete alias
     groups to fix issues with devices using the wrong PCI request-id

   - MMU-401 support for the ARM SMMU driver

   - multi-master IOMMU group support for the ARM SMMU driver

   - various other small fixes all over the place"

* tag 'iommu-updates-v3.18' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (41 commits)
  iommu/vt-d: Work around broken RMRR firmware entries
  iommu/vt-d: Store bus information in RMRR PCI device path
  iommu/vt-d: Only remove domain when device is removed
  driver core: Add BUS_NOTIFY_REMOVED_DEVICE event
  iommu/amd: Fix devid mapping for ivrs_ioapic override
  iommu/irq_remapping: Fix the regression of hpet irq remapping
  iommu: Fix bus notifier breakage
  iommu/amd: Split init_iommu_group() from iommu_init_device()
  iommu: Rework iommu_group_get_for_pci_dev()
  iommu: Make of_device_id array const
  amd_iommu: do not dereference a NULL pointer address.
  iommu/omap: Remove omap_iommu unused owner field
  iommu: Remove iommu_domain_has_cap() API function
  IB/usnic: Convert to use new iommu_capable() API function
  vfio: Convert to use new iommu_capable() API function
  kvm: iommu: Convert to use new iommu_capable() API function
  iommu/tegra: Convert to iommu_capable() API function
  iommu/msm: Convert to iommu_capable() API function
  iommu/vt-d: Convert to iommu_capable() API function
  iommu/fsl: Convert to iommu_capable() API function
  ...
2014-10-15 07:23:49 +02:00
Linus Torvalds 27a9716bc8 Merge tag 'vfio-v3.18-rc1' of git://github.com/awilliam/linux-vfio
Pull VFIO updates from Alex Williamson:
 - Nested IOMMU extension to type1 (Will Deacon)
 - Restore MSIx message before enabling (Gavin Shan)
 - Fix remove path locking (Alex Williamson)

* tag 'vfio-v3.18-rc1' of git://github.com/awilliam/linux-vfio:
  vfio-pci: Fix remove path locking
  drivers/vfio: Export vfio_spapr_iommu_eeh_ioctl() with GPL
  vfio/pci: Restore MSIx message prior to enabling
  PCI: Export MSI message relevant functions
  vfio/iommu_type1: add new VFIO_TYPE1_NESTING_IOMMU IOMMU type
  iommu: introduce domain attribute for nesting IOMMUs
2014-10-11 06:49:24 -04:00
Alex Williamson 93899a679f vfio-pci: Fix remove path locking
Locking both the remove() and release() path results in a deadlock
that should have been obvious.  To fix this we can get and hold the
vfio_device reference as we evaluate whether to do a bus/slot reset.
This will automatically block any remove() calls, allowing us to
remove the explict lock.  Fixes 61d792562b.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Cc: stable@vger.kernel.org	[3.17]
2014-09-29 17:18:39 -06:00
Gavin Shan 0f905ce2b5 drivers/vfio: Export vfio_spapr_iommu_eeh_ioctl() with GPL
The function should have been exported with EXPORT_SYMBOL_GPL()
as part of commit 92d18a6851 ("drivers/vfio: Fix EEH build error").

Suggested-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2014-09-29 10:31:51 -06:00
Gavin Shan b8f02af096 vfio/pci: Restore MSIx message prior to enabling
The MSIx vector table lives in device memory, which may be cleared as
part of a backdoor device reset. This is the case on the IBM IPR HBA
when the BIST is run on the device. When assigned to a QEMU guest,
the guest driver does a pci_save_state(), issues a BIST, then does a
pci_restore_state(). The BIST clears the MSIx vector table, but due
to the way interrupts are configured the pci_restore_state() does not
restore the vector table as expected. Eventually this results in an
EEH error on Power platforms when the device attempts to signal an
interrupt with the zero'd table entry.

Fix the problem by restoring the host cached MSI message prior to
enabling each vector.

Reported-by: Wen Xiong <wenxiong@linux.vnet.ibm.com>
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2014-09-29 10:16:24 -06:00
Will Deacon f5c9ecebaf vfio/iommu_type1: add new VFIO_TYPE1_NESTING_IOMMU IOMMU type
VFIO allows devices to be safely handed off to userspace by putting
them behind an IOMMU configured to ensure DMA and interrupt isolation.
This enables userspace KVM clients, such as kvmtool and qemu, to further
map the device into a virtual machine.

With IOMMUs such as the ARM SMMU, it is then possible to provide SMMU
translation services to the guest operating system, which are nested
with the existing translation installed by VFIO. However, enabling this
feature means that the IOMMU driver must be informed that the VFIO domain
is being created for the purposes of nested translation.

This patch adds a new IOMMU type (VFIO_TYPE1_NESTING_IOMMU) to the VFIO
type-1 driver. The new IOMMU type acts identically to the
VFIO_TYPE1v2_IOMMU type, but additionally sets the DOMAIN_ATTR_NESTING
attribute on its IOMMU domains.

Cc: Joerg Roedel <joro@8bytes.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2014-09-29 10:06:19 -06:00
Chen, Gong 846fc70986 PCI/AER: Rename PCI_ERR_UNC_TRAIN to PCI_ERR_UNC_UND
In PCIe r1.0, sec 5.10.2, bit 0 of the Uncorrectable Error Status, Mask,
and Severity Registers was for "Training Error." In PCIe r1.1, sec 7.10.2,
bit 0 was redefined to be "Undefined."

Rename PCI_ERR_UNC_TRAIN to PCI_ERR_UNC_UND to reflect this change.

No functional change.

[bhelgaas: changelog]
Signed-off-by: Chen, Gong <gong.chen@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2014-09-25 09:42:40 -06:00
Joerg Roedel eb165f0584 vfio: Convert to use new iommu_capable() API function
Cc: Alex Williamson <alex.williamson@redhat.com>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2014-09-25 15:47:45 +02:00
Alexey Kardashevskiy 9b936c960f drivers/vfio: Enable VFIO if EEH is not supported
The existing vfio_pci_open() fails upon error returned from
vfio_spapr_pci_eeh_open(), which breaks POWER7's P5IOC2 PHB
support which this patch brings back.

The patch fixes the issue by dropping the return value of
vfio_spapr_pci_eeh_open().

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2014-08-08 10:39:16 -06:00
Alexey Kardashevskiy 89a2edd62f drivers/vfio: Allow EEH to be built as module
This adds necessary declarations to the SPAPR VFIO EEH module,
otherwise multiple dynamic linker errors reported:

vfio_spapr_eeh: Unknown symbol eeh_pe_set_option (err 0)
vfio_spapr_eeh: Unknown symbol eeh_pe_configure (err 0)
vfio_spapr_eeh: Unknown symbol eeh_pe_reset (err 0)
vfio_spapr_eeh: Unknown symbol eeh_pe_get_state (err 0)
vfio_spapr_eeh: Unknown symbol eeh_iommu_group_to_pe (err 0)
vfio_spapr_eeh: Unknown symbol eeh_dev_open (err 0)
vfio_spapr_eeh: Unknown symbol eeh_pe_set_option (err 0)
vfio_spapr_eeh: Unknown symbol eeh_pe_configure (err 0)
vfio_spapr_eeh: Unknown symbol eeh_pe_reset (err 0)
vfio_spapr_eeh: Unknown symbol eeh_pe_get_state (err 0)
vfio_spapr_eeh: Unknown symbol eeh_iommu_group_to_pe (err 0)
vfio_spapr_eeh: Unknown symbol eeh_dev_open (err 0)

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2014-08-08 10:37:51 -06:00
Gavin Shan 92d18a6851 drivers/vfio: Fix EEH build error
The VFIO related components could be built as dynamic modules.
Unfortunately, CONFIG_EEH can't be configured to "m". The patch
fixes the build errors when configuring VFIO related components
as dynamic modules as follows:

  CC [M]  drivers/vfio/vfio_iommu_spapr_tce.o
In file included from drivers/vfio/vfio.c:33:0:
include/linux/vfio.h:101:43: warning: ‘struct pci_dev’ declared \
inside parameter list [enabled by default]
   :
  WRAP    arch/powerpc/boot/zImage.pseries
  WRAP    arch/powerpc/boot/zImage.maple
  WRAP    arch/powerpc/boot/zImage.pmac
  WRAP    arch/powerpc/boot/zImage.epapr
  MODPOST 1818 modules
ERROR: ".vfio_spapr_iommu_eeh_ioctl" [drivers/vfio/vfio_iommu_spapr_tce.ko]\
undefined!
ERROR: ".vfio_spapr_pci_eeh_open" [drivers/vfio/pci/vfio-pci.ko] undefined!
ERROR: ".vfio_spapr_pci_eeh_release" [drivers/vfio/pci/vfio-pci.ko] undefined!

Reported-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2014-08-08 10:36:20 -06:00