| Message ID | 1304495717.20660.67.camel@localhost.localdomain |
|---|---|
| State | RFC, archived |
| Delegated to: | David Miller |
| Headers | show |
On Wed, 2011-05-04 at 16:13 -0700, Sridhar Samudrala wrote: > On Wed, 2011-05-04 at 00:55 -0700, Shirley Ma wrote: > > Signed-off-by: Shirley Ma <xma@us.ibm.com> > > --- > > > > include/linux/netdevice.h | 10 ++++++++++ > > 1 files changed, 10 insertions(+), 0 deletions(-) > > > > diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h > > index 0249fe7..0808f1e 100644 > > --- a/include/linux/netdevice.h > > +++ b/include/linux/netdevice.h > > @@ -1067,6 +1067,16 @@ struct net_device { > > #define NETIF_F_RXHASH (1 << 28) /* Receive hashing offload */ > > #define NETIF_F_RXCSUM (1 << 29) /* Receive checksumming offload */ > > > > +/* > > + * Bit 31 is for device to map userspace buffers -- zerocopy > > + * Device can set this flag when it supports HIGHDMA. > > + * Device can't recycle this kind of skb buffers. > > + * There are 256 bytes copied, the rest of buffers are mapped. > > + * The userspace callback should only be called when last reference to this skb > > + * is gone. > > + */ > > +#define NETIF_F_ZEROCOPY (1 << 31) > > + > Should we make this TX_ZEROCOPY as we may need a seperate flag for > RX_ZEROCOPY in future? > > Same with socket flag. We might be able to use the same flag for both TX and RX. If RX zero-copy requires only HIGHDMA feature only. If not, then we might need different feature bit. Same for sock flag. > Thanks > Sridhar > > -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 0249fe7..0808f1e 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -1067,6 +1067,16 @@ struct net_device { #define NETIF_F_RXHASH (1 << 28) /* Receive hashing offload */ #define NETIF_F_RXCSUM (1 << 29) /* Receive checksumming offload */ +/* + * Bit 31 is for device to map userspace buffers -- zerocopy + * Device can set this flag when it supports HIGHDMA. + * Device can't recycle this kind of skb buffers. + * There are 256 bytes copied, the rest of buffers are mapped. + * The userspace callback should only be called when last reference to this skb + * is gone. + */ +#define NETIF_F_ZEROCOPY (1 << 31) + /* Segmentation offload features */ #define NETIF_F_GSO_SHIFT 16 #define NETIF_F_GSO_MASK 0x00ff0000
Signed-off-by: Shirley Ma <xma@us.ibm.com> --- include/linux/netdevice.h | 10 ++++++++++ 1 files changed, 10 insertions(+), 0 deletions(-) -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html