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iommu/vt-d: Update to use PCI DMA aliases

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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>
This commit is contained in:
Alex Williamson
2014-07-03 09:51:43 -06:00
committed by Joerg Roedel
parent e17f9ff413
commit 579305f75d
2 changed files with 148 additions and 141 deletions
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55
drivers/iommu/intel_irq_remapping.c
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@@ -369,29 +369,52 @@ static int set_hpet_sid(struct irte *irte, u8 id)
return 0;
}
struct set_msi_sid_data {
struct pci_dev *pdev;
u16 alias;
};
static int set_msi_sid_cb(struct pci_dev *pdev, u16 alias, void *opaque)
{
struct set_msi_sid_data *data = opaque;
data->pdev = pdev;
data->alias = alias;
return 0;
}
static int set_msi_sid(struct irte *irte, struct pci_dev *dev)
{
struct pci_dev *bridge;
struct set_msi_sid_data data;
if (!irte || !dev)
return -1;
/* PCIe device or Root Complex integrated PCI device */
if (pci_is_pcie(dev) || !dev->bus->parent) {
set_irte_sid(irte, SVT_VERIFY_SID_SQ, SQ_ALL_16,
(dev->bus->number << 8) | dev->devfn);
return 0;
}
pci_for_each_dma_alias(dev, set_msi_sid_cb, &data);
bridge = pci_find_upstream_pcie_bridge(dev);
if (bridge) {
if (pci_is_pcie(bridge))/* this is a PCIe-to-PCI/PCIX bridge */
set_irte_sid(irte, SVT_VERIFY_BUS, SQ_ALL_16,
(bridge->bus->number << 8) | dev->bus->number);
else /* this is a legacy PCI bridge */
set_irte_sid(irte, SVT_VERIFY_SID_SQ, SQ_ALL_16,
(bridge->bus->number << 8) | bridge->devfn);
}
/*
* DMA alias provides us with a PCI device and alias. The only case
* where the it will return an alias on a different bus than the
* device is the case of a PCIe-to-PCI bridge, where the alias is for
* the subordinate bus. In this case we can only verify the bus.
*
* If the alias device is on a different bus than our source device
* then we have a topology based alias, use it.
*
* Otherwise, the alias is for a device DMA quirk and we cannot
* assume that MSI uses the same requester ID. Therefore use the
* original device.
*/
if (PCI_BUS_NUM(data.alias) != data.pdev->bus->number)
set_irte_sid(irte, SVT_VERIFY_BUS, SQ_ALL_16,
PCI_DEVID(PCI_BUS_NUM(data.alias),
dev->bus->number));
else if (data.pdev->bus->number != dev->bus->number)
set_irte_sid(irte, SVT_VERIFY_SID_SQ, SQ_ALL_16, data.alias);
else
set_irte_sid(irte, SVT_VERIFY_SID_SQ, SQ_ALL_16,
PCI_DEVID(dev->bus->number, dev->devfn));
return 0;
}