kernel.git/drivers/pci/iov.c, branch linux-4.3.y

PCI: Set SR-IOV NumVFs to zero after enumeration

2016-02-19T22:28:27Z

commit ea9a8854161d9580cfabe011c0ae296ecc0e1d4f upstream. The enumeration path should leave NumVFs set to zero. But after 4449f079722c ("PCI: Calculate maximum number of buses required for VFs"), we call virtfn_max_buses() in the enumeration path, which changes NumVFs. This NumVFs change is visible via lspci and sysfs until a driver enables SR-IOV. Iterate from TotalVFs down to zero so NumVFs is zero when we're finished computing the maximum number of buses. Validate offset and stride in the loop, so we can test it at every possible NumVFs setting. Rename virtfn_max_buses() to compute_max_vf_buses() to hint that it does have a side effect of updating iov->max_VF_buses. [bhelgaas: changelog, rename, allow numVF==1 && stride==0, rework loop, reverse sense of error path] Fixes: 4449f079722c ("PCI: Calculate maximum number of buses required for VFs") Based-on-patch-by: Ethan Zhao Signed-off-by: Alexander Duyck Signed-off-by: Bjorn Helgaas Signed-off-by: Greg Kroah-Hartman

PCI: Add pcibios_iov_resource_alignment() interface

2015-03-31T02:02:36Z

Per the SR-IOV spec r1.1, sec 3.3.14, the required alignment of a PF's IOV BAR is the size of an individual VF BAR, and the size consumed is the individual VF BAR size times NumVFs. The PowerNV platform has additional alignment requirements to help support its Partitionable Endpoint device isolation feature (see Documentation/powerpc/pci_iov_resource_on_powernv.txt). Add a pcibios_iov_resource_alignment() interface to allow platforms to request additional alignment. [bhelgaas: changelog, adapt to reworked pci_sriov_resource_alignment(), drop "align" parameter] Signed-off-by: Wei Yang Acked-by: Bjorn Helgaas Signed-off-by: Benjamin Herrenschmidt

PCI: Add pcibios_sriov_enable() and pcibios_sriov_disable()

2015-03-31T02:02:36Z

VFs are dynamically created when a driver enables them. On some platforms, like PowerNV, special resources are necessary to enable VFs. Add platform hooks for enabling and disabling VFs. Signed-off-by: Wei Yang Acked-by: Bjorn Helgaas Signed-off-by: Benjamin Herrenschmidt

PCI: Export pci_iov_virtfn_bus() and pci_iov_virtfn_devfn()

2015-03-31T02:02:36Z

On PowerNV, some resource reservation is needed for SR-IOV VFs that don't exist at the bootup stage. To do the match between resources and VFs, the code need to get the VF's BDF in advance. Rename virtfn_bus() and virtfn_devfn() to pci_iov_virtfn_bus() and pci_iov_virtfn_devfn() and export them. [bhelgaas: changelog, make "busnr" int] Signed-off-by: Wei Yang Acked-by: Bjorn Helgaas Signed-off-by: Benjamin Herrenschmidt

PCI: Calculate maximum number of buses required for VFs

2015-03-31T02:02:36Z

An SR-IOV device can change its First VF Offset and VF Stride based on the values of ARI Capable Hierarchy and NumVFs. The number of buses required for all VFs is determined by NumVFs, First VF Offset, and VF Stride (see SR-IOV spec r1.1, sec 2.1.2). Previously pci_iov_bus_range() computed how many buses would be required by TotalVFs, but this was based on a single NumVFs value and may not have been the maximum for all NumVFs configurations. Iterate over all valid NumVFs and calculate the maximum number of bus numbers that could ever be required for VFs of this device. [bhelgaas: changelog, compute busnr of NumVFs, not TotalVFs, remove kerenl-doc comment marker] Signed-off-by: Wei Yang Acked-by: Bjorn Helgaas Signed-off-by: Benjamin Herrenschmidt

PCI: Refresh First VF Offset and VF Stride when updating NumVFs

2015-03-31T02:02:36Z

The First VF Offset and VF Stride fields depend on the NumVFs setting, so refresh the cached fields in struct pci_sriov when updating NumVFs. See the SR-IOV spec r1.1, sec 3.3.9 and 3.3.10. [bhelgaas: changelog, remove kernel-doc comment marker] Signed-off-by: Wei Yang Acked-by: Bjorn Helgaas Signed-off-by: Benjamin Herrenschmidt

PCI: Index IOV resources in the conventional style

2015-03-31T02:02:36Z

Most of PCI uses "res = &dev->resource[i]", not "res = dev->resource + i". Use that style in iov.c also. No functional change. Signed-off-by: Bjorn Helgaas Acked-by: Wei Yang Signed-off-by: Benjamin Herrenschmidt

PCI: Keep individual VF BAR size in struct pci_sriov

2015-03-31T02:02:35Z

Currently we don't store the individual VF BAR size. We calculate it when needed by dividing the PF's IOV resource size (which contains space for *all* the VFs) by total_VFs or by reading the BAR in the SR-IOV capability again. Keep the individual VF BAR size in struct pci_sriov.barsz[], add pci_iov_resource_size() to retrieve it, and use that instead of doing the division or reading the SR-IOV capability BAR. [bhelgaas: rename to "barsz[]", simplify barsz[] index computation, remove SR-IOV capability BAR sizing] Signed-off-by: Wei Yang Acked-by: Bjorn Helgaas Signed-off-by: Benjamin Herrenschmidt

PCI: Print PF SR-IOV resource that contains all VF(n) BAR space

2015-03-31T02:02:35Z

When we size VF BAR0, VF BAR1, etc., from the SR-IOV Capability of a PF, we learn the alignment requirement and amount of space consumed by a single VF. But when VFs are enabled, *each* of the NumVFs consumes that amount of space, so the total size of the PF resource is "VF BAR size * NumVFs". Add a printk of the total space consumed by the VFs corresponding to what we already do for normal non-IOV BARs. No functional change; new message only. [bhelgaas: split out into its own patch] Signed-off-by: Wei Yang Acked-by: Bjorn Helgaas Signed-off-by: Benjamin Herrenschmidt

PCI: Print more info in sriov_enable() error message

2015-03-31T02:02:35Z

If we don't have space for all the bus numbers required to enable VFs, print the largest bus number required and the range available. No functional change; improved error message only. Signed-off-by: Bjorn Helgaas Acked-by: Wei Yang Signed-off-by: Benjamin Herrenschmidt