xdp: add reporting of offload mode

Extend the XDP_ATTACHED_* values to include offloaded mode.
Let drivers report whether program is installed in the driver
or the HW by changing the prog_attached field from bool to
u8 (type of the netlink attribute).

Exploit the fact that the value of XDP_ATTACHED_DRV is 1,
therefore since all drivers currently assign the mode with
double negation:
       mode = !!xdp_prog;
no drivers have to be modified.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index a838591aad28616d851d52b67436cc4c167d5ea2..68f5d899d1e6cc54f1c55d26c1d390ae22401417 100644 (file)
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -809,7 +809,8 @@ enum xdp_netdev_command {
        XDP_SETUP_PROG,
        XDP_SETUP_PROG_HW,
        /* Check if a bpf program is set on the device.  The callee should
-        * return true if a program is currently attached and running.
+        * set @prog_attached to one of XDP_ATTACHED_* values, note that "true"
+        * is equivalent to XDP_ATTACHED_DRV.
         */
        XDP_QUERY_PROG,
 };
@@ -827,7 +828,7 @@ struct netdev_xdp {
                };
                /* XDP_QUERY_PROG */
                struct {
-                       bool prog_attached;
+                       u8 prog_attached;
                        u32 prog_id;
                };
        };
@@ -3307,7 +3308,7 @@ struct sk_buff *dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev,
 typedef int (*xdp_op_t)(struct net_device *dev, struct netdev_xdp *xdp);
 int dev_change_xdp_fd(struct net_device *dev, struct netlink_ext_ack *extack,
                      int fd, u32 flags);
-bool __dev_xdp_attached(struct net_device *dev, xdp_op_t xdp_op, u32 *prog_id);
+u8 __dev_xdp_attached(struct net_device *dev, xdp_op_t xdp_op, u32 *prog_id);
 
 int __dev_forward_skb(struct net_device *dev, struct sk_buff *skb);
 int dev_forward_skb(struct net_device *dev, struct sk_buff *skb);

diff --git a/include/uapi/linux/if_link.h b/include/uapi/linux/if_link.h
index ce777ec88e1eccaf37dcf807804cb340c8c2b72d..8d062c58d5cbc9e629a190a87926066ceb778488 100644 (file)
--- a/include/uapi/linux/if_link.h
+++ b/include/uapi/linux/if_link.h
@@ -903,6 +903,7 @@ enum {
        XDP_ATTACHED_NONE = 0,
        XDP_ATTACHED_DRV,
        XDP_ATTACHED_SKB,
+       XDP_ATTACHED_HW,
 };
 
 enum {

diff --git a/net/core/dev.c b/net/core/dev.c
index cd885e9e336378845239464407f842a67b9f9308..a91572aa73d58c9a11febb1810f6bec0158b63df 100644 (file)
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -6934,8 +6934,7 @@ int dev_change_proto_down(struct net_device *dev, bool proto_down)
 }
 EXPORT_SYMBOL(dev_change_proto_down);
 
-bool __dev_xdp_attached(struct net_device *dev, xdp_op_t xdp_op,
-                       u32 *prog_id)
+u8 __dev_xdp_attached(struct net_device *dev, xdp_op_t xdp_op, u32 *prog_id)
 {
        struct netdev_xdp xdp;
 

diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index a5bedd03a63ed094ab65091779a91acd9cea37c4..9a1bd510c8122c7512e1a014066ef68c14e4e34c 100644 (file)
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -1265,10 +1265,10 @@ static u8 rtnl_xdp_attached_mode(struct net_device *dev, u32 *prog_id)
                *prog_id = generic_xdp_prog->aux->id;
                return XDP_ATTACHED_SKB;
        }
-       if (ops->ndo_xdp && __dev_xdp_attached(dev, ops->ndo_xdp, prog_id))
-               return XDP_ATTACHED_DRV;
+       if (!ops->ndo_xdp)
+               return XDP_ATTACHED_NONE;
 
-       return XDP_ATTACHED_NONE;
+       return __dev_xdp_attached(dev, ops->ndo_xdp, prog_id);
 }
 
 static int rtnl_xdp_fill(struct sk_buff *skb, struct net_device *dev)