PCI: Do any VF BAR updates before enabling the BARs

Previously we enabled VFs and enable their memory space before calling
pcibios_sriov_enable().  But pcibios_sriov_enable() may update the VF BARs:
for example, on PPC PowerNV we may change them to manage the association of
VFs to PEs.

Because 64-bit BARs cannot be updated atomically, it's unsafe to update
them while they're enabled.  The half-updated state may conflict with other
devices in the system.

Call pcibios_sriov_enable() before enabling the VFs so any BAR updates
happen while the VF BARs are disabled.

[bhelgaas: changelog]
Tested-by: Carol Soto <clsoto@us.ibm.com>
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
This commit is contained in:
Gavin Shan 2016-10-26 12:15:35 +11:00 committed by Bjorn Helgaas
parent 1600f62534
commit f40ec3c748

View File

@ -306,13 +306,6 @@ static int sriov_enable(struct pci_dev *dev, int nr_virtfn)
return rc; return rc;
} }
pci_iov_set_numvfs(dev, nr_virtfn);
iov->ctrl |= PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE;
pci_cfg_access_lock(dev);
pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
msleep(100);
pci_cfg_access_unlock(dev);
iov->initial_VFs = initial; iov->initial_VFs = initial;
if (nr_virtfn < initial) if (nr_virtfn < initial)
initial = nr_virtfn; initial = nr_virtfn;
@ -323,6 +316,13 @@ static int sriov_enable(struct pci_dev *dev, int nr_virtfn)
goto err_pcibios; goto err_pcibios;
} }
pci_iov_set_numvfs(dev, nr_virtfn);
iov->ctrl |= PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE;
pci_cfg_access_lock(dev);
pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
msleep(100);
pci_cfg_access_unlock(dev);
for (i = 0; i < initial; i++) { for (i = 0; i < initial; i++) {
rc = pci_iov_add_virtfn(dev, i, 0); rc = pci_iov_add_virtfn(dev, i, 0);
if (rc) if (rc)