Re: [PATCHv3 2/8] RDMA/rxe: Support more rdma links in init_net

[Zhu Yanjun <yanjun.zhu@linux.dev>]

在 2023/2/14 14:06, Zhu Yanjun 写道:
> From: Zhu Yanjun <yanjun.zhu@linux.dev>
> 
> In init_net, when several rdma links are created with the command "rdma
> link add", newlink will check whether the udp port 4791 is listening or
> not.
> If not, creating a sock listening on udp port 4791. If yes, increasing the
> reference count of the sock.
> 
> Signed-off-by: Zhu Yanjun <yanjun.zhu@linux.dev>

Add netdev@vger.kernel.org.

Zhu Yanjun

> ---
>   drivers/infiniband/sw/rxe/rxe.c     | 12 ++++++-
>   drivers/infiniband/sw/rxe/rxe_net.c | 55 +++++++++++++++++++++--------
>   drivers/infiniband/sw/rxe/rxe_net.h |  1 +
>   3 files changed, 52 insertions(+), 16 deletions(-)
> 
> diff --git a/drivers/infiniband/sw/rxe/rxe.c b/drivers/infiniband/sw/rxe/rxe.c
> index 64644cb0bb38..0ce6adb43cfc 100644
> --- a/drivers/infiniband/sw/rxe/rxe.c
> +++ b/drivers/infiniband/sw/rxe/rxe.c
> @@ -8,6 +8,7 @@
>   #include <net/addrconf.h>
>   #include "rxe.h"
>   #include "rxe_loc.h"
> +#include "rxe_net.h"
>   
>   MODULE_AUTHOR("Bob Pearson, Frank Zago, John Groves, Kamal Heib");
>   MODULE_DESCRIPTION("Soft RDMA transport");
> @@ -205,14 +206,23 @@ static int rxe_newlink(const char *ibdev_name, struct net_device *ndev)
>   	return err;
>   }
>   
> -static struct rdma_link_ops rxe_link_ops = {
> +struct rdma_link_ops rxe_link_ops = {
>   	.type = "rxe",
>   	.newlink = rxe_newlink,
>   };
>   
>   static int __init rxe_module_init(void)
>   {
> +	int err;
> +
>   	rdma_link_register(&rxe_link_ops);
> +
> +	err = rxe_register_notifier();
> +	if (err) {
> +		pr_err("Failed to register netdev notifier\n");
> +		return -1;
> +	}
> +
>   	pr_info("loaded\n");
>   	return 0;
>   }
> diff --git a/drivers/infiniband/sw/rxe/rxe_net.c b/drivers/infiniband/sw/rxe/rxe_net.c
> index e02e1624bcf4..3ca92e062800 100644
> --- a/drivers/infiniband/sw/rxe/rxe_net.c
> +++ b/drivers/infiniband/sw/rxe/rxe_net.c
> @@ -623,13 +623,23 @@ static struct notifier_block rxe_net_notifier = {
>   
>   static int rxe_net_ipv4_init(void)
>   {
> -	recv_sockets.sk4 = rxe_setup_udp_tunnel(&init_net,
> -				htons(ROCE_V2_UDP_DPORT), false);
> -	if (IS_ERR(recv_sockets.sk4)) {
> -		recv_sockets.sk4 = NULL;
> +	struct sock *sk;
> +	struct socket *sock;
> +
> +	rcu_read_lock();
> +	sk = udp4_lib_lookup(&init_net, 0, 0, htonl(INADDR_ANY),
> +			     htons(ROCE_V2_UDP_DPORT), 0);
> +	rcu_read_unlock();
> +	if (sk)
> +		return 0;
> +
> +	sock = rxe_setup_udp_tunnel(&init_net, htons(ROCE_V2_UDP_DPORT), false);
> +	if (IS_ERR(sock)) {
>   		pr_err("Failed to create IPv4 UDP tunnel\n");
> +		recv_sockets.sk4 = NULL;
>   		return -1;
>   	}
> +	recv_sockets.sk4 = sock;
>   
>   	return 0;
>   }
> @@ -637,24 +647,46 @@ static int rxe_net_ipv4_init(void)
>   static int rxe_net_ipv6_init(void)
>   {
>   #if IS_ENABLED(CONFIG_IPV6)
> +	struct sock *sk;
> +	struct socket *sock;
> +
> +	rcu_read_lock();
> +	sk = udp6_lib_lookup(&init_net, NULL, 0, &in6addr_any,
> +			     htons(ROCE_V2_UDP_DPORT), 0);
> +	rcu_read_unlock();
> +	if (sk)
> +		return 0;
>   
> -	recv_sockets.sk6 = rxe_setup_udp_tunnel(&init_net,
> -						htons(ROCE_V2_UDP_DPORT), true);
> -	if (PTR_ERR(recv_sockets.sk6) == -EAFNOSUPPORT) {
> +	sock = rxe_setup_udp_tunnel(&init_net, htons(ROCE_V2_UDP_DPORT), true);
> +	if (PTR_ERR(sock) == -EAFNOSUPPORT) {
>   		recv_sockets.sk6 = NULL;
>   		pr_warn("IPv6 is not supported, can not create a UDPv6 socket\n");
>   		return 0;
>   	}
>   
> -	if (IS_ERR(recv_sockets.sk6)) {
> +	if (IS_ERR(sock)) {
>   		recv_sockets.sk6 = NULL;
>   		pr_err("Failed to create IPv6 UDP tunnel\n");
>   		return -1;
>   	}
> +	recv_sockets.sk6 = sock;
>   #endif
>   	return 0;
>   }
>   
> +int rxe_register_notifier(void)
> +{
> +	int err;
> +
> +	err = register_netdevice_notifier(&rxe_net_notifier);
> +	if (err) {
> +		pr_err("Failed to register netdev notifier\n");
> +		return -1;
> +	}
> +
> +	return 0;
> +}
> +
>   void rxe_net_exit(void)
>   {
>   	rxe_release_udp_tunnel(recv_sockets.sk6);
> @@ -666,19 +698,12 @@ int rxe_net_init(void)
>   {
>   	int err;
>   
> -	recv_sockets.sk6 = NULL;
> -
>   	err = rxe_net_ipv4_init();
>   	if (err)
>   		return err;
>   	err = rxe_net_ipv6_init();
>   	if (err)
>   		goto err_out;
> -	err = register_netdevice_notifier(&rxe_net_notifier);
> -	if (err) {
> -		pr_err("Failed to register netdev notifier\n");
> -		goto err_out;
> -	}
>   	return 0;
>   err_out:
>   	rxe_net_exit();
> diff --git a/drivers/infiniband/sw/rxe/rxe_net.h b/drivers/infiniband/sw/rxe/rxe_net.h
> index 45d80d00f86b..a222c3eeae12 100644
> --- a/drivers/infiniband/sw/rxe/rxe_net.h
> +++ b/drivers/infiniband/sw/rxe/rxe_net.h
> @@ -18,6 +18,7 @@ struct rxe_recv_sockets {
>   
>   int rxe_net_add(const char *ibdev_name, struct net_device *ndev);
>   
> +int rxe_register_notifier(void);
>   int rxe_net_init(void);
>   void rxe_net_exit(void);
>