On Tue, Apr 24, 2018 at 2:51 PM, Bjorn Helgaas <helgaas@xxxxxxxxxx> wrote: > On Sat, Apr 21, 2018 at 05:22:27PM -0700, Alexander Duyck wrote: >> On Sat, Apr 21, 2018 at 1:34 PM, Bjorn Helgaas <helgaas@xxxxxxxxxx> wrote: > >> > For example, I'm not sure what you mean by "devices where the PF is >> > not capable of managing VF resources." >> > >> > It *sounds* like you're saying the hardware works differently on some >> > devices, but I don't think that's what you mean. I think you're >> > saying something about which drivers are used for the PF and the VF. >> >> That is sort of what I am saying. >> >> So for example with ixgbe there is functionality which is controlled >> in the MMIO space of the PF that affects the functionality of the VFs >> that are generated on the device. The PF has to rearrange the >> resources such as queues and interrupts on the device before it can >> enable SR-IOV, and it could alter those later to limit what the VF is >> capable of doing. >> >> The model I am dealing with via this patch set has a PF that is not >> much different than the VFs other than the fact that it has some >> extended configuration space bits in place for SR-IOV, ARI, ACS, and >> whatever other bits are needed in order to support spawning isolated >> VFs. > > OK, thanks for the explanation, I think I understand what's going on > now, correct me if I'm mistaken. I added a hint about "PF" for Randy, > too. > > These are on pci/virtualization for v4.18. I reviewed them and all of the changes to patches 1 & 2 both below, and in the tree look good to me. Thanks for taking care of all this. - Alex > commit 8effc395c209 > Author: Alexander Duyck <alexander.h.duyck@xxxxxxxxx> > Date: Sat Apr 21 15:23:09 2018 -0500 > > PCI/IOV: Add pci_sriov_configure_simple() > > SR-IOV (Single Root I/O Virtualization) is an optional PCIe capability (see > PCIe r4.0, sec 9). A PCIe Function with the SR-IOV capability is referred > to as a PF (Physical Function). If SR-IOV is enabled on the PF, several > VFs (Virtual Functions) may be created. The VFs can be individually > assigned to virtual machines, which allows them to share a single hardware > device while being isolated from each other. > > Some SR-IOV devices have resources such as queues and interrupts that must > be set up in the PF before enabling the VFs, so they require a PF driver to > do that. > > Other SR-IOV devices don't require any PF setup before enabling VFs. Add a > pci_sriov_configure_simple() interface so PF drivers for such devices can > use it without repeating the VF-enabling code. > > Tested-by: Mark Rustad <mark.d.rustad@xxxxxxxxx> > Signed-off-by: Alexander Duyck <alexander.h.duyck@xxxxxxxxx> > [bhelgaas: changelog, comment] > Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> > Reviewed-by: Greg Rose <gvrose8192@xxxxxxxxx> > Reviewed-by: Christoph Hellwig <hch@xxxxxx>:wq > > commit a8ccf8a66663 > Author: Alexander Duyck <alexander.h.duyck@xxxxxxxxx> > Date: Tue Apr 24 16:47:16 2018 -0500 > > PCI/IOV: Add pci-pf-stub driver for PFs that only enable VFs > > Some SR-IOV PF devices provide no functionality other than acting as a > means of enabling VFs. For these devices, we want to enable the VFs and > assign them to guest virtual machines, but there's no need to have a driver > for the PF itself. > > Add a new pci-pf-stub driver to claim those PF devices and provide the > generic VF enable functionality. An administrator can use the sysfs > "sriov_numvfs" file to enable VFs, then assign them to guests. > > For now I only have one example ID provided by Amazon in terms of devices > that require this functionality. The general idea is that in the future we > will see other devices added as vendors come up with devices where the PF > is more or less just a lightweight shim used to allocate VFs. > > Signed-off-by: Alexander Duyck <alexander.h.duyck@xxxxxxxxx> > [bhelgaas: changelog] > Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> > Reviewed-by: Greg Rose <gvrose8192@xxxxxxxxx> > Reviewed-by: Christoph Hellwig <hch@xxxxxx> > > commit 115ddc491922 > Author: Alexander Duyck <alexander.h.duyck@xxxxxxxxx> > Date: Tue Apr 24 16:47:22 2018 -0500 > > net: ena: Use pci_sriov_configure_simple() to enable VFs > > Instead of implementing our own version of a SR-IOV configuration stub in > the ena driver, use the existing pci_sriov_configure_simple() function. > > Signed-off-by: Alexander Duyck <alexander.h.duyck@xxxxxxxxx> > Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> > Reviewed-by: Greg Rose <gvrose8192@xxxxxxxxx> > Reviewed-by: Christoph Hellwig <hch@xxxxxx> > > commit 74d986abc20b > Author: Alexander Duyck <alexander.h.duyck@xxxxxxxxx> > Date: Tue Apr 24 16:47:27 2018 -0500 > > nvme-pci: Use pci_sriov_configure_simple() to enable VFs > > Instead of implementing our own version of a SR-IOV configuration stub in > the nvme driver, use the existing pci_sriov_configure_simple() function. > > Signed-off-by: Alexander Duyck <alexander.h.duyck@xxxxxxxxx> > Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> > Reviewed-by: Christoph Hellwig <hch@xxxxxx>
