Re: [PATCH V14 10/21] PCI: Add pcibios_sriov_enable() and pcibios_sriov_disable()

[Gavin Shan <gwshan@linux.vnet.ibm.com>]

On Fri, Mar 20, 2015 at 11:06:26AM +0800, Wei Yang wrote:
>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 <weiyang@linux.vnet.ibm.com>
>---
> drivers/pci/iov.c |   19 +++++++++++++++++++
> 1 file changed, 19 insertions(+)
>
>diff --git a/drivers/pci/iov.c b/drivers/pci/iov.c
>index 5643a10..64c4692 100644
>--- a/drivers/pci/iov.c
>+++ b/drivers/pci/iov.c
>@@ -220,6 +220,11 @@ static void virtfn_remove(struct pci_dev *dev, int id, int reset)
> 	pci_dev_put(dev);
> }
> 
>+int __weak pcibios_sriov_enable(struct pci_dev *pdev, u16 num_vfs)
>+{
>+       return 0;
>+}
>+
> static int sriov_enable(struct pci_dev *dev, int nr_virtfn)
> {
> 	int rc;
>@@ -231,6 +236,7 @@ static int sriov_enable(struct pci_dev *dev, int nr_virtfn)
> 	struct pci_sriov *iov = dev->sriov;
> 	int bars = 0;
> 	int bus;
>+	int retval;
> 
> 	if (!nr_virtfn)
> 		return 0;
>@@ -307,6 +313,12 @@ static int sriov_enable(struct pci_dev *dev, int nr_virtfn)
> 	if (nr_virtfn < initial)
> 		initial = nr_virtfn;
> 
>+	if ((retval = pcibios_sriov_enable(dev, initial))) {
>+		dev_err(&dev->dev, "failure %d from pcibios_sriov_enable()\n",
>+			retval);
>+		return retval;
>+	}
>+
> 	for (i = 0; i < initial; i++) {
> 		rc = virtfn_add(dev, i, 0);
> 		if (rc)
>@@ -335,6 +347,11 @@ failed:
> 	return rc;
> }
> 
>+int __weak pcibios_sriov_disable(struct pci_dev *pdev)
>+{
>+       return 0;
>+}
>+

Since you will have to v15, I would suggest to drop the return
value for this function. It seems there isn't a reason to have "int"
return value here.

Thanks,
Gavin

> static void sriov_disable(struct pci_dev *dev)
> {
> 	int i;
>@@ -346,6 +363,8 @@ static void sriov_disable(struct pci_dev *dev)
> 	for (i = 0; i < iov->num_VFs; i++)
> 		virtfn_remove(dev, i, 0);
> 
>+	pcibios_sriov_disable(dev);
>+
> 	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);
>-- 
>1.7.9.5
>
>_______________________________________________
>Linuxppc-dev mailing list
>Linuxppc-dev@lists.ozlabs.org
>https://lists.ozlabs.org/listinfo/linuxppc-dev