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10 commits

Author SHA1 Message Date
Bjorn Helgaas
ff9bee895c PCI: Move ATS declarations to linux/pci.h so they're all together
Move ATS declarations to linux/pci.h so they're all in one place.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Joerg Roedel <jroedel@suse.de>
2015-08-13 15:59:58 -05:00
Bjorn Helgaas
d544d75ac9 PCI: Embed ATS info directly into struct pci_dev
The pci_ats struct is small and will get smaller, so I don't think it's
worth allocating it separately from the pci_dev struct.

Embed the ATS fields directly into struct pci_dev.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Joerg Roedel <jroedel@suse.de>
2015-08-13 15:57:21 -05:00
Bjorn Helgaas
edc90fee91 PCI: Allocate ATS struct during enumeration
Previously, we allocated pci_ats structures when an IOMMU driver called
pci_enable_ats().  An SR-IOV VF shares the STU setting with its PF, so when
enabling ATS on the VF, we allocated a pci_ats struct for the PF if it
didn't already have one.  We held the sriov->lock to serialize threads
concurrently enabling ATS on several VFS so only one would allocate the PF
pci_ats.

Gregor reported a deadlock here:

  pci_enable_sriov
    sriov_enable
      virtfn_add
        mutex_lock(dev->sriov->lock)      # acquire sriov->lock
        pci_device_add
          device_add
            BUS_NOTIFY_ADD_DEVICE notifier chain
            iommu_bus_notifier
              amd_iommu_add_device        # iommu_ops.add_device
                init_iommu_group
                  iommu_group_get_for_dev
                    iommu_group_add_device
                      __iommu_attach_device
                        amd_iommu_attach_device  # iommu_ops.attach_device
                          attach_device
                            pci_enable_ats
                              mutex_lock(dev->sriov->lock) # deadlock

There's no reason to delay allocating the pci_ats struct, and if we
allocate it for each device at enumeration-time, there's no need for
locking in pci_enable_ats().

Allocate pci_ats struct during enumeration, when we initialize other
capabilities.

Note that this implementation requires ATS to be enabled on the PF first,
before on any of the VFs because the PF controls the STU for all the VFs.

Link: http://permalink.gmane.org/gmane.linux.kernel.iommu/9433
Reported-by: Gregor Dick <gdick@solarflare.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Joerg Roedel <jroedel@suse.de>
2015-08-13 15:57:21 -05:00
Stephen Hemminger
b340cacc1b PCI: Removed unused parts of Page Request Interface support
My philosophy is unused code is dead code.  And dead code is subject to bit
rot and is a likely source of bugs.  Use it or lose it.

This reverts parts of c320b976d7 ("PCI: Add implementation for PRI
capability"), removing these interfaces:

    pci_pri_enabled()
    pci_pri_stopped()
    pci_pri_status()

[bhelgaas: split to separate patch]
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: Joerg Roedel <joro@8bytes.org>
2014-01-10 14:00:47 -07:00
Bjorn Helgaas
f39d5b7291 PCI: Remove "extern" from function declarations
We had an inconsistent mix of using and omitting the "extern" keyword
on function declarations in header files.  This removes them all.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2013-04-17 10:21:17 -06:00
Joerg Roedel
466b3ddfbc PCI: Fix compile errors with PCI_ATS and !PCI_IOV
The ats and sroiv members of 'struct pci_dev' are required
for the ATS code already, even without IOV support compiled
in. So depend on ATS here. This is fine with PCI_IOV too
because it selects PCI_ATS. Also the prototypes for ATS
need to be available for PCI_ATS.

Reported-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2011-10-31 10:23:57 -07:00
Joerg Roedel
086ac11f64 PCI: Add support for PASID capability
Devices supporting Process Address Space Identifiers
(PASIDs) can use an IOMMU to access multiple IO address
spaces at the same time. A PCIe device indicates support for
this feature by implementing the PASID capability. This
patch adds support for the capability to the Linux kernel.

Reviewed-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2011-10-14 09:05:35 -07:00
Joerg Roedel
c320b976d7 PCI: Add implementation for PRI capability
Implement the necessary functions to handle PRI capabilities
on PCIe devices. With PRI devices behind an IOMMU can signal
page fault conditions to software and recover from such
faults.

Reviewed-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2011-10-14 09:05:34 -07:00
Joerg Roedel
db3c33c6d3 PCI: Move ATS implementation into own file
ATS does not depend on IOV support, so move the code into
its own file. This file will also include support for the
PRI and PASID capabilities later.
Also give ATS its own Kconfig variable to allow selecting it
without IOV support.

Reviewed-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2011-10-14 09:05:33 -07:00
Joerg Roedel
5cdede2408 PCI: Move ATS declarations in seperate header file
This patch moves the relevant declarations from the local
header file in drivers/pci to a more accessible locations so
that it can be used by the AMD IOMMU driver too.
The file is named pci-ats.h because support for the PCI PRI
capability will also be added there in a later patch-set.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2011-04-11 09:01:41 +02:00