iommu/vt-d: Add helper to set an IRTE to verify only the bus number

The current code uses set_irte_sid() with SVT_VERIFY_BUS and PCI_DEVID
to set the SID value. However, this is very confusing because, with
SVT_VERIFY_BUS, the SID value is not a PCI devfn address, but the start
and end bus numbers to match against.

According to the Intel Virtualization Technology for Directed I/O
Architecture Specification, Rev. 3.0, page 9-36:

  The most significant 8-bits of the SID field contains the Startbus#,
  and the least significant 8-bits of the SID field contains the Endbus#.
  Interrupt requests that reference this IRTE must have a requester-id
  whose bus# (most significant 8-bits of requester-id) has a value equal
  to or within the Startbus# to Endbus# range.

So to make this more clear, introduce a new set_irte_verify_bus() that
explicitly takes a start bus and end bus so that we can stop abusing
the PCI_DEVID macro.

This helper function will be called a second time in an subsequent patch.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
This commit is contained in:
Logan Gunthorpe 2019-02-13 10:54:45 -07:00 committed by Joerg Roedel
parent f096d6657a
commit 9ca8261173

View File

@ -294,6 +294,18 @@ static void set_irte_sid(struct irte *irte, unsigned int svt,
irte->sid = sid;
}
/*
* Set an IRTE to match only the bus number. Interrupt requests that reference
* this IRTE must have a requester-id whose bus number is between or equal
* to the start_bus and end_bus arguments.
*/
static void set_irte_verify_bus(struct irte *irte, unsigned int start_bus,
unsigned int end_bus)
{
set_irte_sid(irte, SVT_VERIFY_BUS, SQ_ALL_16,
(start_bus << 8) | end_bus);
}
static int set_ioapic_sid(struct irte *irte, int apic)
{
int i;
@ -391,9 +403,8 @@ static int set_msi_sid(struct irte *irte, struct pci_dev *dev)
* 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));
set_irte_verify_bus(irte, 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