PCI: Update NumVFs register when disabling SR-IOV

Currently, we only update NumVFs register during sriov_enable().
This register should also be updated during sriov_disable() and when
sriov_enable() fails.  Otherwise, we will get the stale "Number of VFs"
info from lspci.

[bhelgaas: changelog]
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

diff --git a/drivers/pci/iov.c b/drivers/pci/iov.c
index de4034ee0efa87ad6ca279b8a280e59e69dd559f..e73bdae447cc3cdd01d0a215fa0d291513405b0d 100644 (file)
--- a/drivers/pci/iov.c
+++ b/drivers/pci/iov.c
@@ -286,7 +286,6 @@ static int sriov_enable(struct pci_dev *dev, int nr_virtfn)
            (!(iov->cap & PCI_SRIOV_CAP_VFM) && (nr_virtfn > initial)))
                return -EINVAL;
 
-       pci_write_config_word(dev, iov->pos + PCI_SRIOV_NUM_VF, nr_virtfn);
        pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_OFFSET, &offset);
        pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_STRIDE, &stride);
        if (!offset || (nr_virtfn > 1 && !stride))
@@ -334,6 +333,7 @@ static int sriov_enable(struct pci_dev *dev, int nr_virtfn)
                        return rc;
        }
 
+       pci_write_config_word(dev, iov->pos + PCI_SRIOV_NUM_VF, 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);
@@ -368,6 +368,7 @@ failed:
        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);
+       pci_write_config_word(dev, iov->pos + PCI_SRIOV_NUM_VF, 0);
        ssleep(1);
        pci_cfg_access_unlock(dev);
 
@@ -401,6 +402,7 @@ static void sriov_disable(struct pci_dev *dev)
                sysfs_remove_link(&dev->dev.kobj, "dep_link");
 
        iov->num_VFs = 0;
+       pci_write_config_word(dev, iov->pos + PCI_SRIOV_NUM_VF, 0);
 }
 
 static int sriov_init(struct pci_dev *dev, int pos)