linux-toradex.git/virt, branch tegra-next

Merge remote-tracking branch 'origin/dev/k3.3-rc1-iommu' into android-tegra-nv-3.1

2012-02-01T10:33:06+00:00

Change-Id: I9001bb291779f107bbcb593d48f9f0f734074d0e

iommu/core: split mapping to page sizes as supported by the hardware

2012-01-23T09:11:36+00:00

When mapping a memory region, split it to page sizes as supported
by the iommu hardware. Always prefer bigger pages, when possible,
in order to reduce the TLB pressure.

The logic to do that is now added to the IOMMU core, so neither the iommu
drivers themselves nor users of the IOMMU API have to duplicate it.

This allows a more lenient granularity of mappings; traditionally the
IOMMU API took 'order' (of a page) as a mapping size, and directly let
the low level iommu drivers handle the mapping, but now that the IOMMU
core can split arbitrary memory regions into pages, we can remove this
limitation, so users don't have to split those regions by themselves.

Currently the supported page sizes are advertised once and they then
remain static. That works well for OMAP and MSM but it would probably
not fly well with intel's hardware, where the page size capabilities
seem to have the potential to be different between several DMA
remapping devices.

register_iommu() currently sets a default pgsize behavior, so we can convert
the IOMMU drivers in subsequent patches. After all the drivers
are converted, the temporary default settings will be removed.

Mainline users of the IOMMU API (kvm and omap-iovmm) are adopted
to deal with bytes instead of page order.

Many thanks to Joerg Roedel  for significant review!

Signed-off-by: Ohad Ben-Cohen 
Cc: David Brown 
Cc: David Woodhouse 
Cc: Joerg Roedel 
Cc: Stepan Moskovchenko 
Cc: KyongHo Cho 
Cc: Hiroshi DOYU 
Cc: Laurent Pinchart 
Cc: kvm@vger.kernel.org
Signed-off-by: Joerg Roedel

iommu/core: Convert iommu_found to iommu_present

2012-01-23T09:11:35+00:00

With per-bus iommu_ops the iommu_found function needs to
work on a bus_type too. This patch adds a bus_type parameter
to that function and converts all call-places.
The function is also renamed to iommu_present because the
function now checks if an iommu is present for a given bus
and does not check for a global iommu anymore.

Signed-off-by: Joerg Roedel

iommu/core: Add bus_type parameter to iommu_domain_alloc

2012-01-23T09:11:35+00:00

This is necessary to store a pointer to the bus-specific
iommu_ops in the iommu-domain structure. It will be used
later to call into bus-specific iommu-ops.

Signed-off-by: Joerg Roedel 

Conflicts:

	drivers/iommu/iommu.c

Change-Id: Iddbd561739552b663a4be293f1992314eb0f775a

KVM: Device assignment permission checks

2012-01-18T15:31:54+00:00

(cherry picked from commit 3d27e23b17010c668db311140b17bbbb70c78fb9)

Only allow KVM device assignment to attach to devices which:

 - Are not bridges
 - Have BAR resources (assume others are special devices)
 - The user has permissions to use

Assigning a bridge is a configuration error, it's not supported, and
typically doesn't result in the behavior the user is expecting anyway.
Devices without BAR resources are typically chipset components that
also don't have host drivers.  We don't want users to hold such devices
captive or cause system problems by fencing them off into an iommu
domain.  We determine "permission to use" by testing whether the user
has access to the PCI sysfs resource files.  By default a normal user
will not have access to these files, so it provides a good indication
that an administration agent has granted the user access to the device.

[Yang Bai: add missing #include]
[avi: fix comment style]

Signed-off-by: Alex Williamson 
Signed-off-by: Yang Bai 
Signed-off-by: Marcelo Tosatti 
Signed-off-by: Greg Kroah-Hartman

KVM: Remove ability to assign a device without iommu support

2012-01-18T15:31:53+00:00

(cherry picked from commit 423873736b78f549fbfa2f715f2e4de7e6c5e1e9)

This option has no users and it exposes a security hole that we
can allow devices to be assigned without iommu protection.  Make
KVM_DEV_ASSIGN_ENABLE_IOMMU a mandatory option.

Signed-off-by: Alex Williamson 
Signed-off-by: Marcelo Tosatti 
Signed-off-by: Greg Kroah-Hartman

KVM: IOMMU: Disable device assignment without interrupt remapping

2011-07-24T08:50:42+00:00

IOMMU interrupt remapping support provides a further layer of
isolation for device assignment by preventing arbitrary interrupt
block DMA writes by a malicious guest from reaching the host.  By
default, we should require that the platform provides interrupt
remapping support, with an opt-in mechanism for existing behavior.

Both AMD IOMMU and Intel VT-d2 hardware support interrupt
remapping, however we currently only have software support on
the Intel side.  Users wishing to re-enable device assignment
when interrupt remapping is not supported on the platform can
use the "allow_unsafe_assigned_interrupts=1" module option.

[avi: break long lines]

Signed-off-by: Alex Williamson 
Signed-off-by: Marcelo Tosatti 
Signed-off-by: Avi Kivity

KVM: MMU: mmio page fault support

2011-07-24T08:50:40+00:00

The idea is from Avi:

| We could cache the result of a miss in an spte by using a reserved bit, and
| checking the page fault error code (or seeing if we get an ept violation or
| ept misconfiguration), so if we get repeated mmio on a page, we don't need to
| search the slot list/tree.
| (https://lkml.org/lkml/2011/2/22/221)

When the page fault is caused by mmio, we cache the info in the shadow page
table, and also set the reserved bits in the shadow page table, so if the mmio
is caused again, we can quickly identify it and emulate it directly

Searching mmio gfn in memslots is heavy since we need to walk all memeslots, it
can be reduced by this feature, and also avoid walking guest page table for
soft mmu.

[jan: fix operator precedence issue]

Signed-off-by: Xiao Guangrong 
Signed-off-by: Jan Kiszka 
Signed-off-by: Avi Kivity

KVM: MMU: filter out the mmio pfn from the fault pfn

2011-07-24T08:50:34+00:00

If the page fault is caused by mmio, the gfn can not be found in memslots, and
'bad_pfn' is returned on gfn_to_hva path, so we can use 'bad_pfn' to identify
the mmio page fault.
And, to clarify the meaning of mmio pfn, we return fault page instead of bad
page when the gfn is not allowd to prefetch

Signed-off-by: Xiao Guangrong 
Signed-off-by: Avi Kivity

KVM: introduce kvm_read_guest_cached

2011-07-12T10:17:01+00:00

Introduce kvm_read_guest_cached() function in addition to write one we
already have.

[ by glauber: export function signature in kvm header ]

Signed-off-by: Gleb Natapov 
Signed-off-by: Glauber Costa 
Acked-by: Rik van Riel 
Tested-by: Eric Munson 
Signed-off-by: Avi Kivity