[libvirt] [PATCH 3/4 v2] interface: Add functions to get sriov PF/VF relationship of a net interface

[Stefan Berger]

On 08/12/2011 07:14 PM, Roopa Prabhu wrote:
> From: Roopa Prabhu<roprabhu at cisco.com>
>
> This patch adds the following functions to get PF/VF relationship of an SRIOV
> network interface:
> ifaceIsVirtualFunction: Function to check if a network interface is a SRIOV VF
> ifaceGetVirtualFunctionIndex: Function to get VF index if a network interface is a SRIOV VF
> ifaceGetPhysicalFunction: Function to get the PF net interface name of a SRIOV VF net interface
>
> Signed-off-by: Roopa Prabhu<roprabhu at cisco.com>
> Signed-off-by: Christian Benvenuti<benve at cisco.com>
> Signed-off-by: David Wang<dwang2 at cisco.com>
> ---
>   src/util/interface.c |  150 ++++++++++++++++++++++++++++++++++++++++++++++++++
>   src/util/interface.h |    9 +++
>   2 files changed, 159 insertions(+), 0 deletions(-)
>
>
> diff --git a/src/util/interface.c b/src/util/interface.c
> index 8b4522b..ec00606 100644
> --- a/src/util/interface.c
> +++ b/src/util/interface.c
> @@ -45,6 +45,8 @@
>   #include "virfile.h"
>   #include "memory.h"
>   #include "netlink.h"
> +#include "pci.h"
> +#include "logging.h"
>
>   #define VIR_FROM_THIS VIR_FROM_NET
>
> @@ -1196,3 +1198,151 @@ ifaceRestoreMacAddress(const char *linkdev,
>
>       return rc;
>   }
> +
> +#if __linux__
> +static int
> +ifaceSysfsFile(char **pf_sysfs_device_link, const char *ifname,
> +               const char *file)
> +{
> +
> +    if (virAsprintf(pf_sysfs_device_link, NET_SYSFS "%s/%s",
> +        ifname, file)<  0) {
> +        virReportOOMError();
> +        return -1;
> +    }
> +
> +    return 0;
> +}
> +
> +static int
> +ifaceSysfsDeviceFile(char **pf_sysfs_device_link, const char *ifname,
> +                     const char *file)
> +{
> +
> +    if (virAsprintf(pf_sysfs_device_link, NET_SYSFS "%s/device/%s",
> +        ifname, file)<  0) {
> +        virReportOOMError();
> +        return -1;
> +    }
> +
> +    return 0;
> +}
> +
> +/**
> + * ifaceIsVirtualFunction
> + *
> + * @ifname : name of the interface
> + *
> + * Checks if an interface is a SRIOV virtual function.
> + *
> + * Returns 1 if interface is SRIOV virtual function, 0 if not and -1 if error
> + *
> + */
> +int
> +ifaceIsVirtualFunction(const char *ifname)
> +{
> +    char *if_sysfs_device_link = NULL;
> +    int ret = -1;
> +
> +    if (ifaceSysfsFile(&if_sysfs_device_link, ifname, "device"))
> +        return ret;
> +
> +    ret = pciDeviceIsVirtualFunction(if_sysfs_device_link);
> +
> +    VIR_FREE(if_sysfs_device_link);
> +
> +    return ret;
> +}
> +
> +/**
> + * ifaceGetVirtualFunctionIndex
> + *
> + * @pfname : name of the physical function interface name
> + * @vfname : name of the virtual function interface name
> + * @vf_index : Pointer to int. Contains vf index of interface upon successful
> + *             return
> + *
> + * Returns 0 on success, -1 on failure
> + *
> + */
> +int
> +ifaceGetVirtualFunctionIndex(const char *pfname, const char *vfname,
> +                             int *vf_index)
> +{
> +    char *pf_sysfs_device_link = NULL, *vf_sysfs_device_link = NULL;
> +    int ret = -1;
> +
> +    if (ifaceSysfsFile(&pf_sysfs_device_link, pfname, "device"))
> +        return ret;
> +
> +    if (ifaceSysfsFile(&vf_sysfs_device_link, vfname, "device")) {
> +        VIR_FREE(pf_sysfs_device_link);
> +        return ret;
> +    }
> +
> +    ret = pciGetVirtualFunctionIndex(pf_sysfs_device_link,
> +                                     vf_sysfs_device_link,
> +                                     vf_index);
> +
> +    VIR_FREE(pf_sysfs_device_link);
> +    VIR_FREE(vf_sysfs_device_link);
> +
> +    return ret;
> +}
> +
> +/**
> + * ifaceGetPhysicalFunction
> + *
> + * @ifname : name of the physical function interface name
> + * @pfname : Contains sriov physical function for interface ifname
> + *           upon successful return
> + *
> + * Returns 0 on success, -1 on failure
> + *
> + */
> +int
> +ifaceGetPhysicalFunction(const char *ifname, char **pfname)
> +{
> +    char *physfn_sysfs_path = NULL;
> +    int ret = -1;
> +
> +    if (ifaceSysfsDeviceFile(&physfn_sysfs_path, ifname, "physfn"))
> +        return ret;
> +
> +    ret = pciDeviceNetName(physfn_sysfs_path, pfname);
> +
> +    VIR_FREE(physfn_sysfs_path);
> +
> +    return ret;
> +}
> +#else
> +
> +int
> +ifaceIsVirtualFunction(const char *ifname)
> +{
> +    ifaceError(VIR_ERR_INTERNAL_ERROR, "%s",
> +               _("ifaceIsVirtualFunction is not supported on non-linux "
> +               "platforms"));
> +    return -ENOSYS;
Since above functions are described to return -1 on error, also do this 
in these ones here.

    Stefan

> +}
> +
> +int
> +ifaceGetVirtualFunctionIndex(const char *pfname, const char *vfname,
> +                             int *vf_index)
> +{
> +    ifaceError(VIR_ERR_INTERNAL_ERROR, "%s",
> +               _("ifaceGetVirtualFunctionIndex is not supported on non-linux "
> +               "platforms"));
> +    return -ENOSYS;
> +}
> +
> +int
> +ifaceGetPhysicalFunction(const char *ifname, char **pfname)
> +{
> +    ifaceError(VIR_ERR_INTERNAL_ERROR, "%s",
> +               _("ifaceGetPhysicalFunction is not supported on non-linux "
> +               "platforms"));
> +    return -ENOSYS;
> +}
> +
> +#endif /* __linux__ */
> diff --git a/src/util/interface.h b/src/util/interface.h
> index 47c0eb0..bdd37e5 100644
> --- a/src/util/interface.h
> +++ b/src/util/interface.h
> @@ -27,6 +27,8 @@ struct nlattr;
>   # include "datatypes.h"
>   # include "network.h"
>
> +#define NET_SYSFS "/sys/class/net/"
> +
>   int ifaceGetFlags(const char *name, short *flags);
>   int ifaceIsUp(const char *name, bool *up);
>
> @@ -79,4 +81,11 @@ int ifaceReplaceMacAddress(const unsigned char *macaddress,
>   int ifaceRestoreMacAddress(const char *linkdev,
>                              const char *stateDir);
>
> +int ifaceIsVirtualFunction(const char *ifname);
> +
> +int ifaceGetVirtualFunctionIndex(const char *pfname, const char *vfname,
> +                                 int *vf_index);
> +
> +int ifaceGetPhysicalFunction(const char *ifname, char **pfname);
> +
>   #endif /* __VIR_INTERFACE_H__ */
>