iommu/core: Create central IOMMU group lookup/creation interface

Currently each IOMMU driver that supports IOMMU groups has its own
code for discovering the base device used in grouping.  This code
is generally not specific to the IOMMU hardware, but to the bus of
the devices managed by the IOMMU.  We can therefore create a common
interface for supporting devices on different buses.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
iommu/amd: Update to use PCI DMA aliases

AMD-Vi already has a concept of an alias provided via the IVRS table.
Now that PCI-core also understands aliases, we need to incorporate
both aspects when programming the IOMMU.  IVRS is generally quite
reliable, so we continue to prefer it when an alias is present.  For
cases where we have an IVRS alias that does not match the PCI alias
or where PCI does not report an alias, report the mismatch to allow
us to collect more quirks and dynamically incorporate the alias into
the device alias quirks where possible.

This should allow AMD-Vi to work with devices like Marvell and Ricoh
with DMA function alias quirks unknown to the BIOS.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
iommu/amd: Use iommu_group_get_for_dev()

The common iommu_group_get_for_dev() allows us to greatly simplify
our group lookup for a new device.  Also, since we insert IVRS
aliases into the PCI DMA alias quirks, we should alway come up with
the same results as the existing code.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
iommu/vt-d: Use iommu_group_get_for_dev()

The IOMMU code now provides a common interface for finding or
creating an IOMMU group for a device on PCI buses.  Make use of it
and remove piles of code.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
iommu/vt-d: Update to use PCI DMA aliases

VT-d code currently makes use of pci_find_upstream_pcie_bridge() in
order to find the topology based alias of a device.  This function has
a few problems.  First, it doesn't check the entire alias path of the
device to the root bus, therefore if a PCIe device is masked upstream,
the wrong result is produced.  Also, it's known to get confused and
give up when it crosses a bridge from a conventional PCI bus to a PCIe
bus that lacks a PCIe capability.  The PCI-core provided DMA alias
support solves both of these problems and additionally adds support
for DMA function quirks allowing VT-d to work with devices like
Marvell and Ricoh with known broken requester IDs.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
iommu/fsl: Use iommu_group_get_for_dev() for IOMMU groups

Drop custom code and use IOMMU provided grouping support for PCI.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Acked-by: Varun Sethi <varun.sethi@freescale.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
iommu: Remove pci.h

The single helper here no longer has any users.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
iommu: Add sysfs support for IOMMUs

IOMMUs currently have no common representation to userspace, most
seem to have no representation at all aside from a few printks
on bootup.  There are however features of IOMMUs that are useful
to know about.  For instance the IOMMU might support superpages,
making use of processor large/huge pages more important in a device
assignment scenario.  It's also useful to create cross links between
devices and IOMMU hardware units, so that users might be able to
load balance their devices to avoid thrashing a single hardware unit.

This patch adds a device create and destroy interface as well as
device linking, making it very lightweight for an IOMMU driver to add
basic support.  IOMMU drivers can provide additional attributes
automatically by using an attribute_group.

The attributes exposed are expected to be relatively device specific,
the means to retrieve them certainly are, so there are currently no
common attributes for the new class created here.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
iommu/vt-d: Make use of IOMMU sysfs support

Register our DRHD IOMMUs, cross link devices, and provide a base set
of attributes for the IOMMU.  Note that IRQ remapping support parses
the DMAR table very early in boot, well before the iommu_class can
reasonably be setup, so our registration is split between
intel_iommu_init(), which occurs later, and alloc_iommu(), which
typically occurs much earlier, but may happen at any time later
with IOMMU hot-add support.

On a typical desktop system, this provides the following (pruned):

$ find /sys | grep dmar
/sys/devices/virtual/iommu/dmar0
/sys/devices/virtual/iommu/dmar0/devices
/sys/devices/virtual/iommu/dmar0/devices/0000:00:02.0
/sys/devices/virtual/iommu/dmar0/intel-iommu
/sys/devices/virtual/iommu/dmar0/intel-iommu/cap
/sys/devices/virtual/iommu/dmar0/intel-iommu/ecap
/sys/devices/virtual/iommu/dmar0/intel-iommu/address
/sys/devices/virtual/iommu/dmar0/intel-iommu/version
/sys/devices/virtual/iommu/dmar1
/sys/devices/virtual/iommu/dmar1/devices
/sys/devices/virtual/iommu/dmar1/devices/0000:00:00.0
/sys/devices/virtual/iommu/dmar1/devices/0000:00:01.0
/sys/devices/virtual/iommu/dmar1/devices/0000:00:16.0
/sys/devices/virtual/iommu/dmar1/devices/0000:00:1a.0
/sys/devices/virtual/iommu/dmar1/devices/0000:00:1b.0
/sys/devices/virtual/iommu/dmar1/devices/0000:00:1c.0
...
/sys/devices/virtual/iommu/dmar1/intel-iommu
/sys/devices/virtual/iommu/dmar1/intel-iommu/cap
/sys/devices/virtual/iommu/dmar1/intel-iommu/ecap
/sys/devices/virtual/iommu/dmar1/intel-iommu/address
/sys/devices/virtual/iommu/dmar1/intel-iommu/version
/sys/class/iommu/dmar0
/sys/class/iommu/dmar1

(devices also link back to the dmar units)

This makes address, version, capabilities, and extended capabilities
available, just like printed on boot.  I've tried not to duplicate
data that can be found in the DMAR table, with the exception of the
address, which provides an easy way to associate the sysfs device with
a DRHD entry in the DMAR.  It's tempting to add scopes and RMRR data
here, but the full DMAR table is already exposed under /sys/firmware/
and therefore already provides a way for userspace to learn such
details.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
iommu/amd: Add sysfs support

AMD-Vi support for IOMMU sysfs.  This allows us to associate devices
with a specific IOMMU device and examine the capabilities and features
of that IOMMU.  The AMD IOMMU is hosted on and actual PCI device, so
we make that device the parent for the IOMMU class device.  This
initial implementaiton exposes only the capability header and extended
features register for the IOMMU.

# find /sys | grep ivhd
/sys/devices/pci0000:00/0000:00:00.2/iommu/ivhd0
/sys/devices/pci0000:00/0000:00:00.2/iommu/ivhd0/devices
/sys/devices/pci0000:00/0000:00:00.2/iommu/ivhd0/devices/0000:00:00.0
/sys/devices/pci0000:00/0000:00:00.2/iommu/ivhd0/devices/0000:00:02.0
/sys/devices/pci0000:00/0000:00:00.2/iommu/ivhd0/devices/0000:00:04.0
/sys/devices/pci0000:00/0000:00:00.2/iommu/ivhd0/devices/0000:00:09.0
/sys/devices/pci0000:00/0000:00:00.2/iommu/ivhd0/devices/0000:00:11.0
/sys/devices/pci0000:00/0000:00:00.2/iommu/ivhd0/devices/0000:00:12.0
/sys/devices/pci0000:00/0000:00:00.2/iommu/ivhd0/devices/0000:00:12.2
/sys/devices/pci0000:00/0000:00:00.2/iommu/ivhd0/devices/0000:00:13.0
...
/sys/devices/pci0000:00/0000:00:00.2/iommu/ivhd0/power
/sys/devices/pci0000:00/0000:00:00.2/iommu/ivhd0/power/control
...
/sys/devices/pci0000:00/0000:00:00.2/iommu/ivhd0/device
/sys/devices/pci0000:00/0000:00:00.2/iommu/ivhd0/subsystem
/sys/devices/pci0000:00/0000:00:00.2/iommu/ivhd0/amd-iommu
/sys/devices/pci0000:00/0000:00:00.2/iommu/ivhd0/amd-iommu/cap
/sys/devices/pci0000:00/0000:00:00.2/iommu/ivhd0/amd-iommu/features
/sys/devices/pci0000:00/0000:00:00.2/iommu/ivhd0/uevent
/sys/class/iommu/ivhd0

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
iommu: Constify struct iommu_ops

This structure is read-only data and should never be modified.

Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
iommu: Fix compile error in iommu-sysfs.c

Add missing include of <linux/slab.h>.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
iommu: Fix IOMMU sysfs stubs

0-day kernel build testing reports:

   arch/x86/kvm/x86.o: In function `iommu_device_destroy':
>> (.text+0x7a0a): multiple definition of `iommu_device_destroy'
   arch/x86/kvm/../../../virt/kvm/vfio.o:vfio.c:(.text+0x490): first defined here
   arch/x86/kvm/x86.o: In function `iommu_device_link':
>> (.text+0x7a15): multiple definition of `iommu_device_link'
   arch/x86/kvm/../../../virt/kvm/vfio.o:vfio.c:(.text+0x49b): first defined here
   arch/x86/kvm/x86.o: In function `iommu_device_unlink':
>> (.text+0x7a25): multiple definition of `iommu_device_unlink'
   arch/x86/kvm/../../../virt/kvm/vfio.o:vfio.c:(.text+0x4ab): first defined here
   arch/x86/kvm/x86.o: In function `iommu_device_create':
>> (.text+0x79f8): multiple definition of `iommu_device_create'
   arch/x86/kvm/../../../virt/kvm/vfio.o:vfio.c:(.text+0x47e): first defined here

These are due to failing to define the stubs as static inline.  Fix.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Merge branch 'core' into x86/vt-d

Conflicts:
	drivers/iommu/intel-iommu.c
iommu/vt-d: Match segment number when searching for dev_iotlb capable devices

For virtual machine and static identity domains, there may be devices
from different PCI segments associated with the same domain.
So function iommu_support_dev_iotlb() should also match PCI segment
number (iommu unit) when searching for dev_iotlb capable devices.

Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
iommu/vt-d: Use correct domain id to flush virtual machine domains

For virtual machine domains, domain->id is a virtual id, and the real
domain id written into context entry is dynamically allocated.
So use the real domain id instead of domain->id when flushing iotlbs
for virtual machine domains.

Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
iommu/vt-d: Introduce helper functions to improve code readability

Introduce domain_type_is_vm() and domain_type_is_vm_or_si() to improve
code readability.

Also kill useless macro DOMAIN_FLAG_P2P_MULTIPLE_DEVICES.

Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
iommu/vt-d: Introduce helper functions to make code symmetric for readability

Introduce domain_attach_iommu()/domain_detach_iommu() and refine
iommu_attach_domain()/iommu_detach_domain() to make code symmetric
and improve readability.

Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
iommu/vt-d: Allocate dynamic domain id for virtual domains only

Check the same domain id is allocated for si_domain on each IOMMU,
otherwise the IOTLB flush for si_domain will fail.

Now the rules to allocate and manage domain id are:
1) For normal and static identity domains, domain id is allocated
   when creating domain structure. And this id will be written into
   context entry.
2) For virtual machine domain, a virtual id is allocated when creating
   domain. And when binding virtual machine domain to an iommu, a real
   domain id is allocated on demand and this domain id will be written
   into context entry. So domain->id for virtual machine domain may be
   different from the domain id written into context entry(used by
   hardware).

Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
iommu/vt-d: Fix possible invalid memory access caused by free_dmar_iommu()

Static identity and virtual machine domains may be cached in
iommu->domain_ids array after corresponding IOMMUs have been removed
from domain->iommu_bmp. So we should check domain->iommu_bmp before
decreasing domain->iommu_count in function free_dmar_iommu(), otherwise
it may cause free of inuse domain data structure.

Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>