Re: [PATCH v2 7/7] PCI: Set NumVFs before computing how many buses VFs require

[Wei Yang <weiyang@linux.vnet.ibm.com>]

On Thu, Oct 29, 2015 at 05:23:36PM -0500, Bjorn Helgaas wrote:
>From: Alexander Duyck <aduyck@mirantis.com>
>
>VF bus numbers depend on the First VF Offset and VF Stride, and per
>sections 3.3.9 and 3.3.10 of the SR-IOV spec r1.1, these depend on the
>NumVF value.
>
>Wait until after we set NumVFs to compute and validate the bus number of
>the last VF.
>
>[bhelgaas: changelog, add spec reference, split to separate patch for
>reviewability]
>Signed-off-by: Alexander Duyck <aduyck@mirantis.com>
>Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
>---
> drivers/pci/iov.c |   18 ++++++++++--------
> 1 file changed, 10 insertions(+), 8 deletions(-)
>
>diff --git a/drivers/pci/iov.c b/drivers/pci/iov.c
>index bd1c4fa..9d29712 100644
>--- a/drivers/pci/iov.c
>+++ b/drivers/pci/iov.c
>@@ -274,13 +274,6 @@ static int sriov_enable(struct pci_dev *dev, int nr_virtfn)
> 		return -ENOMEM;
> 	}
>
>-	bus = pci_iov_virtfn_bus(dev, nr_virtfn - 1);
>-	if (bus > dev->bus->busn_res.end) {
>-		dev_err(&dev->dev, "can't enable %d VFs (bus %02x out of range of %pR)\n",
>-			nr_virtfn, bus, &dev->bus->busn_res);
>-		return -ENOMEM;
>-	}
>-
> 	if (pci_enable_resources(dev, bars)) {
> 		dev_err(&dev->dev, "SR-IOV: IOV BARS not allocated\n");
> 		return -ENOMEM;
>@@ -304,6 +297,15 @@ static int sriov_enable(struct pci_dev *dev, int nr_virtfn)
> 	}
>
> 	pci_iov_set_numvfs(dev, nr_virtfn);

How about move it up?

>+
>+	bus = pci_iov_virtfn_bus(dev, nr_virtfn - 1);
>+	if (bus > dev->bus->busn_res.end) {
>+		dev_err(&dev->dev, "can't enable %d VFs (bus %02x out of range of %pR)\n",
>+			nr_virtfn, bus, &dev->bus->busn_res);
>+		rc = -ENOMEM;
>+		goto err_bus;
>+	}
>+
> 	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);
>@@ -342,7 +344,7 @@ err_pcibios:
> 	pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl);
> 	ssleep(1);
> 	pci_cfg_access_unlock(dev);
>-
>+err_bus:
> 	if (iov->link != dev->devfn)
> 		sysfs_remove_link(&dev->dev.kobj, "dep_link");
>

-- 
Richard Yang
Help you, Help me