Commit 4e3c60ed authored by David S. Miller's avatar David S. Miller
Browse files

Merge branch 'generic-xdp-followups' 



Daniel Borkmann says:

====================
Two generic xdp related follow-ups

Two follow-ups for the generic XDP API, would be great if
both could still be considered, since the XDP API is not
frozen yet. For details please see individual patches.

v1 -> v2:
  - Implemented feedback from Jakub Kicinski (reusing
    attribute on dump), thanks!
  - Rest as is.
====================

Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parents 0a5539f6 d67b9cd2

include/linux/netdevice.h

+6 −2
Original line number Diff line number Diff line
@@ -3296,11 +3296,15 @@ int dev_get_phys_port_id(struct net_device *dev, 
int dev_get_phys_port_name(struct net_device *dev,

			   char *name, size_t len);

int dev_change_proto_down(struct net_device *dev, bool proto_down);

int dev_change_xdp_fd(struct net_device *dev, struct netlink_ext_ack *extack,

		      int fd, u32 flags);

struct sk_buff *validate_xmit_skb_list(struct sk_buff *skb, struct net_device *dev);

struct sk_buff *dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev,

				    struct netdev_queue *txq, int *ret);



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);



int __dev_forward_skb(struct net_device *dev, struct sk_buff *skb);

int dev_forward_skb(struct net_device *dev, struct sk_buff *skb);

bool is_skb_forwardable(const struct net_device *dev,

include/uapi/linux/if_link.h

+11 −2
Original line number Diff line number Diff line
@@ -888,9 +888,18 @@ enum { 
/* XDP section */



#define XDP_FLAGS_UPDATE_IF_NOEXIST	(1U << 0)

#define XDP_FLAGS_SKB_MODE		(2U << 0)

#define XDP_FLAGS_SKB_MODE		(1U << 1)

#define XDP_FLAGS_DRV_MODE		(1U << 2)

#define XDP_FLAGS_MASK			(XDP_FLAGS_UPDATE_IF_NOEXIST | \

					 XDP_FLAGS_SKB_MODE)

					 XDP_FLAGS_SKB_MODE | \

					 XDP_FLAGS_DRV_MODE)



/* These are stored into IFLA_XDP_ATTACHED on dump. */

enum {

	XDP_ATTACHED_NONE = 0,

	XDP_ATTACHED_DRV,

	XDP_ATTACHED_SKB,

};



enum {

	IFLA_XDP_UNSPEC,

net/core/dev.c

+38 −19
Original line number Diff line number Diff line
@@ -6852,6 +6852,32 @@ 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)

{

	struct netdev_xdp xdp;



	memset(&xdp, 0, sizeof(xdp));

	xdp.command = XDP_QUERY_PROG;



	/* Query must always succeed. */

	WARN_ON(xdp_op(dev, &xdp) < 0);

	return xdp.prog_attached;

}



static int dev_xdp_install(struct net_device *dev, xdp_op_t xdp_op,

			   struct netlink_ext_ack *extack,

			   struct bpf_prog *prog)

{

	struct netdev_xdp xdp;



	memset(&xdp, 0, sizeof(xdp));

	xdp.command = XDP_SETUP_PROG;

	xdp.extack = extack;

	xdp.prog = prog;



	return xdp_op(dev, &xdp);

}



/**

 *	dev_change_xdp_fd - set or clear a bpf program for a device rx path

 *	@dev: device
@@ -6864,41 +6890,34 @@ EXPORT_SYMBOL(dev_change_proto_down); 
int dev_change_xdp_fd(struct net_device *dev, struct netlink_ext_ack *extack,

		      int fd, u32 flags)

{

	int (*xdp_op)(struct net_device *dev, struct netdev_xdp *xdp);

	const struct net_device_ops *ops = dev->netdev_ops;

	struct bpf_prog *prog = NULL;

	struct netdev_xdp xdp;

	xdp_op_t xdp_op, xdp_chk;

	int err;



	ASSERT_RTNL();



	xdp_op = ops->ndo_xdp;

	xdp_op = xdp_chk = ops->ndo_xdp;

	if (!xdp_op && (flags & XDP_FLAGS_DRV_MODE))

		return -EOPNOTSUPP;

	if (!xdp_op || (flags & XDP_FLAGS_SKB_MODE))

		xdp_op = generic_xdp_install;

	if (xdp_op == xdp_chk)

		xdp_chk = generic_xdp_install;



	if (fd >= 0) {

		if (flags & XDP_FLAGS_UPDATE_IF_NOEXIST) {

			memset(&xdp, 0, sizeof(xdp));

			xdp.command = XDP_QUERY_PROG;



			err = xdp_op(dev, &xdp);

			if (err < 0)

				return err;

			if (xdp.prog_attached)

		if (xdp_chk && __dev_xdp_attached(dev, xdp_chk))

			return -EEXIST;

		if ((flags & XDP_FLAGS_UPDATE_IF_NOEXIST) &&

		    __dev_xdp_attached(dev, xdp_op))

			return -EBUSY;

		}



		prog = bpf_prog_get_type(fd, BPF_PROG_TYPE_XDP);

		if (IS_ERR(prog))

			return PTR_ERR(prog);

	}



	memset(&xdp, 0, sizeof(xdp));

	xdp.command = XDP_SETUP_PROG;

	xdp.extack = extack;

	xdp.prog = prog;



	err = xdp_op(dev, &xdp);

	err = dev_xdp_install(dev, xdp_op, extack, prog);

	if (err < 0 && prog)

		bpf_prog_put(prog);

net/core/rtnetlink.c

+23 −22
Original line number Diff line number Diff line
@@ -899,8 +899,7 @@ static size_t rtnl_port_size(const struct net_device *dev, 
static size_t rtnl_xdp_size(void)

{

	size_t xdp_size = nla_total_size(0) +	/* nest IFLA_XDP */

			  nla_total_size(1) +	/* XDP_ATTACHED */

			  nla_total_size(4);	/* XDP_FLAGS */

			  nla_total_size(1);	/* XDP_ATTACHED */



	return xdp_size;

}
@@ -1247,37 +1246,34 @@ static int rtnl_fill_link_ifmap(struct sk_buff *skb, struct net_device *dev) 
	return 0;

}



static u8 rtnl_xdp_attached_mode(struct net_device *dev)

{

	const struct net_device_ops *ops = dev->netdev_ops;



	ASSERT_RTNL();



	if (rcu_access_pointer(dev->xdp_prog))

		return XDP_ATTACHED_SKB;

	if (ops->ndo_xdp && __dev_xdp_attached(dev, ops->ndo_xdp))

		return XDP_ATTACHED_DRV;



	return XDP_ATTACHED_NONE;

}



static int rtnl_xdp_fill(struct sk_buff *skb, struct net_device *dev)

{

	struct nlattr *xdp;

	u32 xdp_flags = 0;

	u8 val = 0;

	int err;



	xdp = nla_nest_start(skb, IFLA_XDP);

	if (!xdp)

		return -EMSGSIZE;

	if (rcu_access_pointer(dev->xdp_prog)) {

		xdp_flags = XDP_FLAGS_SKB_MODE;

		val = 1;

	} else if (dev->netdev_ops->ndo_xdp) {

		struct netdev_xdp xdp_op = {};



		xdp_op.command = XDP_QUERY_PROG;

		err = dev->netdev_ops->ndo_xdp(dev, &xdp_op);

		if (err)

			goto err_cancel;

		val = xdp_op.prog_attached;

	}

	err = nla_put_u8(skb, IFLA_XDP_ATTACHED, val);

	if (err)

		goto err_cancel;



	if (xdp_flags) {

		err = nla_put_u32(skb, IFLA_XDP_FLAGS, xdp_flags);

	err = nla_put_u8(skb, IFLA_XDP_ATTACHED,

			 rtnl_xdp_attached_mode(dev));

	if (err)

		goto err_cancel;

	}



	nla_nest_end(skb, xdp);

	return 0;
@@ -2199,6 +2195,11 @@ static int do_setlink(const struct sk_buff *skb, 
				err = -EINVAL;

				goto errout;

			}

			if ((xdp_flags & XDP_FLAGS_SKB_MODE) &&

			    (xdp_flags & XDP_FLAGS_DRV_MODE)) {

				err = -EINVAL;

				goto errout;

			}

		}



		if (xdp[IFLA_XDP_FD]) {

samples/bpf/xdp1_user.c

+6 −2
Original line number Diff line number Diff line
@@ -62,13 +62,14 @@ static void usage(const char *prog) 
	fprintf(stderr,

		"usage: %s [OPTS] IFINDEX\n\n"

		"OPTS:\n"

		"    -S    use skb-mode\n",

		"    -S    use skb-mode\n"

		"    -N    enforce native mode\n",

		prog);

}



int main(int argc, char **argv)

{

	const char *optstr = "S";

	const char *optstr = "SN";

	char filename[256];

	int opt;
@@ -77,6 +78,9 @@ int main(int argc, char **argv) 
		case 'S':

			xdp_flags |= XDP_FLAGS_SKB_MODE;

			break;

		case 'N':

			xdp_flags |= XDP_FLAGS_DRV_MODE;

			break;

		default:

			usage(basename(argv[0]));

			return 1;

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