Commit 13ce2daa authored by Maciej Fijalkowski's avatar Maciej Fijalkowski Committed by Alexei Starovoitov
Browse files

xsk: add new netlink attribute dedicated for ZC max frags 



Introduce new netlink attribute NETDEV_A_DEV_XDP_ZC_MAX_SEGS that will
carry maximum fragments that underlying ZC driver is able to handle on
TX side. It is going to be included in netlink response only when driver
supports ZC. Any value higher than 1 implies multi-buffer ZC support on
underlying device.

Signed-off-by: default avatarMaciej Fijalkowski <maciej.fijalkowski@intel.com>
Link: https://lore.kernel.org/r/20230719132421.584801-11-maciej.fijalkowski@intel.com


Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
parent 07428da9

Documentation/netlink/specs/netdev.yaml

+6 −0
Original line number Diff line number Diff line
@@ -62,6 +62,12 @@ attribute-sets: 
        type: u64

        enum: xdp-act

        enum-as-flags: true

      -

        name: xdp_zc_max_segs

        doc: max fragment count supported by ZC driver

        type: u32

        checks:

          min: 1



operations:

  list:

include/linux/netdevice.h

+1 −0
Original line number Diff line number Diff line
@@ -2250,6 +2250,7 @@ struct net_device { 
#define GRO_MAX_SIZE		(8 * 65535u)

	unsigned int		gro_max_size;

	unsigned int		gro_ipv4_max_size;

	unsigned int		xdp_zc_max_segs;

	rx_handler_func_t __rcu	*rx_handler;

	void __rcu		*rx_handler_data;

include/uapi/linux/netdev.h

+1 −0
Original line number Diff line number Diff line
@@ -41,6 +41,7 @@ enum { 
	NETDEV_A_DEV_IFINDEX = 1,

	NETDEV_A_DEV_PAD,

	NETDEV_A_DEV_XDP_FEATURES,

	NETDEV_A_DEV_XDP_ZC_MAX_SEGS,



	__NETDEV_A_DEV_MAX,

	NETDEV_A_DEV_MAX = (__NETDEV_A_DEV_MAX - 1)

net/core/dev.c

+1 −0
Original line number Diff line number Diff line
@@ -10613,6 +10613,7 @@ struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name, 
	dev_net_set(dev, &init_net);



	dev->gso_max_size = GSO_LEGACY_MAX_SIZE;

	dev->xdp_zc_max_segs = 1;

	dev->gso_max_segs = GSO_MAX_SEGS;

	dev->gro_max_size = GRO_LEGACY_MAX_SIZE;

	dev->gso_ipv4_max_size = GSO_LEGACY_MAX_SIZE;

net/core/netdev-genl.c

+8 −0
Original line number Diff line number Diff line
@@ -25,6 +25,14 @@ netdev_nl_dev_fill(struct net_device *netdev, struct sk_buff *rsp, 
		return -EINVAL;

	}



	if (netdev->xdp_features & NETDEV_XDP_ACT_XSK_ZEROCOPY) {

		if (nla_put_u32(rsp, NETDEV_A_DEV_XDP_ZC_MAX_SEGS,

				netdev->xdp_zc_max_segs)) {

			genlmsg_cancel(rsp, hdr);

			return -EINVAL;

		}

	}



	genlmsg_end(rsp, hdr);



	return 0;