Commit 6ad7969a authored by Breno Leitao's avatar Breno Leitao Committed by Jakub Kicinski
Browse files

netpoll: Extract IPv6 address retrieval function 



Extract the IPv6 address retrieval logic from netpoll_setup() into
a dedicated helper function netpoll_take_ipv6() to improve code
organization and readability.

The function handles obtaining the local IPv6 address from the
network device, including proper address type matching between
local and remote addresses (link-local vs global), and includes
appropriate error handling when IPv6 is not supported or no
suitable address is available.

Signed-off-by: default avatarBreno Leitao <leitao@debian.org>
Reviewed-by: default avatarSimon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250618-netpoll_ip_ref-v1-3-c2ac00fe558f@debian.org


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 3699f992

net/core/netpoll.c

+44 −32
Original line number Diff line number Diff line
@@ -598,6 +598,47 @@ static void netpoll_wait_carrier(struct netpoll *np, struct net_device *ndev, 
	}

}



/*

 * Take the IPv6 from ndev and populate local_ip structure in netpoll

 */

static int netpoll_take_ipv6(struct netpoll *np, struct net_device *ndev)

{

	char buf[MAC_ADDR_STR_LEN + 1];

	int err = -EDESTADDRREQ;

	struct inet6_dev *idev;



	if (!IS_ENABLED(CONFIG_IPV6)) {

		np_err(np, "IPv6 is not supported %s, aborting\n",

		       egress_dev(np, buf));

		return -EINVAL;

	}



	idev = __in6_dev_get(ndev);

	if (idev) {

		struct inet6_ifaddr *ifp;



		read_lock_bh(&idev->lock);

		list_for_each_entry(ifp, &idev->addr_list, if_list) {

			if (!!(ipv6_addr_type(&ifp->addr) & IPV6_ADDR_LINKLOCAL) !=

				!!(ipv6_addr_type(&np->remote_ip.in6) & IPV6_ADDR_LINKLOCAL))

				continue;

			/* Got the IP, let's return */

			np->local_ip.in6 = ifp->addr;

			err = 0;

			break;

		}

		read_unlock_bh(&idev->lock);

	}

	if (err) {

		np_err(np, "no IPv6 address for %s, aborting\n",

		       egress_dev(np, buf));

		return err;

	}



	np_info(np, "local IPv6 %pI6c\n", &np->local_ip.in6);

	return 0;

}



/*

 * Take the IPv4 from ndev and populate local_ip structure in netpoll

 */
@@ -675,41 +716,12 @@ int netpoll_setup(struct netpoll *np) 
			err = netpoll_take_ipv4(np, ndev);

			if (err)

				goto put;

			ip_overwritten = true;

		} else {

#if IS_ENABLED(CONFIG_IPV6)

			struct inet6_dev *idev;



			err = -EDESTADDRREQ;

			idev = __in6_dev_get(ndev);

			if (idev) {

				struct inet6_ifaddr *ifp;



				read_lock_bh(&idev->lock);

				list_for_each_entry(ifp, &idev->addr_list, if_list) {

					if (!!(ipv6_addr_type(&ifp->addr) & IPV6_ADDR_LINKLOCAL) !=

					    !!(ipv6_addr_type(&np->remote_ip.in6) & IPV6_ADDR_LINKLOCAL))

						continue;

					np->local_ip.in6 = ifp->addr;

					ip_overwritten = true;

					err = 0;

					break;

				}

				read_unlock_bh(&idev->lock);

			}

			if (err) {

				np_err(np, "no IPv6 address for %s, aborting\n",

				       egress_dev(np, buf));

				goto put;

			} else

				np_info(np, "local IPv6 %pI6c\n", &np->local_ip.in6);

#else

			np_err(np, "IPv6 is not supported %s, aborting\n",

			       egress_dev(np, buf));

			err = -EINVAL;

			err = netpoll_take_ipv6(np, ndev);

			if (err)

				goto put;

#endif

		}

		ip_overwritten = true;

	}



	err = __netpoll_setup(np, ndev);