Re: [SR-IOV driver example 2/3] PF driver: integrate with SR-IOV core

Greg KH
2008-11-26T17:01:28Z

On Wed, Nov 26, 2008 at 10:21:56PM +0800, Yu Zhao wrote:
> This patch integrates the IGB driver with the SR-IOV core. It shows how
> the SR-IOV API is used to support the capability. Obviously people does
> not need to put much effort to integrate the PF driver with SR-IOV core.
> All SR-IOV standard stuff are handled by SR-IOV core and PF driver only
> concerns the device specific resource allocation and deallocation once it
> gets the necessary information (i.e. number of Virtual Functions) from
> the callback function.
>
> ---
> drivers/net/igb/igb_main.c | 30 ++++++++++++++++++++++++++++++
> 1 files changed, 30 insertions(+), 0 deletions(-)
>
> diff --git a/drivers/net/igb/igb_main.c b/drivers/net/igb/igb_main.c
> index bc063d4..b8c7dc6 100644
> --- a/drivers/net/igb/igb_main.c
> +++ b/drivers/net/igb/igb_main.c
> @@ -139,6 +139,7 @@ void igb_set_mc_list_pools(struct igb_adapter *, struct e1000_hw *, int, u16);
> static int igb_vmm_control(struct igb_adapter *, bool);
> static int igb_set_vf_mac(struct net_device *, int, u8*);
> static void igb_mbox_handler(struct igb_adapter *);
> +static int igb_virtual(struct pci_dev *, int);
> #endif
>
> static int igb_suspend(struct pci_dev *, pm_message_t);
> @@ -184,6 +185,9 @@ static struct pci_driver igb_driver = {
> #endif
> .shutdown = igb_shutdown,
> .err_handler = &igb_err_handler,
> +#ifdef CONFIG_PCI_IOV
> + .virtual = igb_virtual
> +#endif

#ifdef should not be needed, right?

> };
>
> static int global_quad_port_a; /* global quad port a indication */
> @@ -5107,6 +5111,32 @@ void igb_set_mc_list_pools(struct igb_adapter *adapter,
> reg_data |= (1 << 25);
> wr32(E1000_VMOLR(pool), reg_data);
> }
> +
> +static int
> +igb_virtual(struct pci_dev *pdev, int nr_virtfn)
> +{
> + unsigned char my_mac_addr[6] = {0x00, 0xDE, 0xAD, 0xBE, 0xEF, 0xFF};
> + struct net_device *netdev = pci_get_drvdata(pdev);
> + struct igb_adapter *adapter = netdev_priv(netdev);
> + int i;
> +
> + if (nr_virtfn > 7)
> + return -EINVAL;

Why the check for 7? Is that the max virtual functions for this card?
Shouldn't that be a define somewhere so it's easier to fix in future
versions of this hardware? :)

> +
> + if (nr_virtfn) {
> + for (i = 0; i < nr_virtfn; i++) {
> + printk(KERN_INFO "SR-IOV: VF %d is enabled\n", i);

Use dev_info() please, that shows the exact pci device and driver that
emitted the message.

> + my_mac_addr[5] = (unsigned char)i;
> + igb_set_vf_mac(netdev, i, my_mac_addr);
> + igb_set_vf_vmolr(adapter, i);
> + }
> + } else
> + printk(KERN_INFO "SR-IOV is disabled\n");

Is that really true? (oh, use dev_info as well.) What happens if you
had called this with "5" and then later with "0", you never destroyed
those existing virtual functions, yet the code does:

> + adapter->vfs_allocated_count = nr_virtfn;

Which makes the driver think they are not present. What happens when
the driver later goes to shut down? Are those resources freed up
properly?

thanks,

greg k-h