Re: [PATCH net-next 4/5] nfp: add .ndo_get_devlink
From: Michal Kubecek <hidden>
Date: 2019-02-22 10:04:53
On Thu, Feb 21, 2019 at 09:46:19AM -0800, Jakub Kicinski wrote:
quoted hunk ↗ jump to hunk
Support getting devlink instance from a new NDO. Signed-off-by: Jakub Kicinski <redacted> --- drivers/net/ethernet/netronome/nfp/nfp_app.h | 2 ++ drivers/net/ethernet/netronome/nfp/nfp_devlink.c | 11 +++++++++++ drivers/net/ethernet/netronome/nfp/nfp_net_common.c | 1 + drivers/net/ethernet/netronome/nfp/nfp_net_repr.c | 1 + 4 files changed, 15 insertions(+)diff --git a/drivers/net/ethernet/netronome/nfp/nfp_app.h b/drivers/net/ethernet/netronome/nfp/nfp_app.h index d578d856a009..f8d422713705 100644 --- a/drivers/net/ethernet/netronome/nfp/nfp_app.h +++ b/drivers/net/ethernet/netronome/nfp/nfp_app.h@@ -433,4 +433,6 @@ int nfp_app_nic_vnic_alloc(struct nfp_app *app, struct nfp_net *nn, int nfp_app_nic_vnic_init_phy_port(struct nfp_pf *pf, struct nfp_app *app, struct nfp_net *nn, unsigned int id); +struct devlink *nfp_devlink_get_devlink(struct net_device *netdev); + #endifdiff --git a/drivers/net/ethernet/netronome/nfp/nfp_devlink.c b/drivers/net/ethernet/netronome/nfp/nfp_devlink.c index db2da99f6aa7..e9eca99cf493 100644 --- a/drivers/net/ethernet/netronome/nfp/nfp_devlink.c +++ b/drivers/net/ethernet/netronome/nfp/nfp_devlink.c@@ -376,3 +376,14 @@ void nfp_devlink_port_unregister(struct nfp_port *port) { devlink_port_unregister(&port->dl_port); } + +struct devlink *nfp_devlink_get_devlink(struct net_device *netdev) +{ + struct nfp_app *app; + + app = nfp_app_from_netdev(netdev); + if (!app) + return NULL; + + return priv_to_devlink(app->pf); +}
AFAICS this would return a pointer to zero initialized struct devlink
when built with CONFIG_DEVLINK=n. Then devlink_compat_running_version()
would execute
if (!dev->netdev_ops->ndo_get_devlink)
return;
devlink = dev->netdev_ops->ndo_get_devlink(dev);
if (!devlink || !devlink->ops->info_get)
return;
with non-null devlink but null devlink->ops so that it dereferences null
pointer (and so does devlink_compat_flash_update()).
Maybe it would be safer not to call ndo_get_devlink directly and have
an inline wrapper like
#if IS_ENABLED(CONFIG_NET_DEVLINK)
static inline struct devlink *dev_get_devlink(struct net_device *dev)
{
if (dev->netdev_ops->ndo_get_devlink)
return dev->netdev_ops->ndo_get_devlink();
else
retrurn NULL;
}
#else
static inline struct devlink *dev_get_devlink(struct net_device *dev)
{
return NULL;
}
#endif
so that one can simply call the wrapper and check return value for NULL.
Michal