Commit 1305b0c2 authored by Geliang Tang's avatar Geliang Tang Committed by Paolo Abeni
Browse files

mptcp: pm: define struct mptcp_pm_ops 



In order to allow users to develop their own BPF-based path manager,
this patch defines a struct ops "mptcp_pm_ops" for an MPTCP path
manager, which contains a set of interfaces. Currently only init()
and release() interfaces are included, subsequent patches will add
others step by step.

Add a set of functions to register, unregister, find and validate a
given path manager struct ops.

"list" is used to add this path manager to mptcp_pm_list list when
it is registered. "name" is used to identify this path manager.
mptcp_pm_find() uses "name" to find a path manager on the list.

mptcp_pm_unregister is not used in this set, but will be invoked in
.unreg of struct bpf_struct_ops. mptcp_pm_validate() will be invoked
in .validate of struct bpf_struct_ops. That's why they are exported.

Signed-off-by: default avatarGeliang Tang <tanggeliang@kylinos.cn>
Reviewed-by: default avatarMatthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: default avatarMatthieu Baerts (NGI0) <matttbe@kernel.org>
Reviewed-by: default avatarSimon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250313-net-next-mptcp-pm-ops-intro-v1-6-f4e4a88efc50@kernel.org


Signed-off-by: default avatarPaolo Abeni <pabeni@redhat.com>
parent eff5b157

include/net/mptcp.h

+12 −0
Original line number Diff line number Diff line
@@ -14,6 +14,7 @@ 


struct mptcp_info;

struct mptcp_sock;

struct mptcp_pm_addr_entry;

struct seq_file;



/* MPTCP sk_buff extension data */
@@ -121,6 +122,17 @@ struct mptcp_sched_ops { 
	void (*release)(struct mptcp_sock *msk);

} ____cacheline_aligned_in_smp;



#define MPTCP_PM_NAME_MAX	16



struct mptcp_pm_ops {

	char			name[MPTCP_PM_NAME_MAX];

	struct module		*owner;

	struct list_head	list;



	void (*init)(struct mptcp_sock *msk);

	void (*release)(struct mptcp_sock *msk);

} ____cacheline_aligned_in_smp;



#ifdef CONFIG_MPTCP

void mptcp_init(void);

net/mptcp/pm.c

+50 −0
Original line number Diff line number Diff line
@@ -5,6 +5,8 @@ 
 */

#define pr_fmt(fmt) "MPTCP: " fmt



#include <linux/rculist.h>

#include <linux/spinlock.h>

#include "protocol.h"

#include "mib.h"
@@ -18,6 +20,9 @@ struct mptcp_pm_add_entry { 
	struct mptcp_sock	*sock;

};



static DEFINE_SPINLOCK(mptcp_pm_list_lock);

static LIST_HEAD(mptcp_pm_list);



/* path manager helpers */



/* if sk is ipv4 or ipv6_only allows only same-family local and remote addresses,
@@ -1015,3 +1020,48 @@ void __init mptcp_pm_init(void) 
	mptcp_pm_kernel_register();

	mptcp_pm_nl_init();

}



/* Must be called with rcu read lock held */

struct mptcp_pm_ops *mptcp_pm_find(const char *name)

{

	struct mptcp_pm_ops *pm_ops;



	list_for_each_entry_rcu(pm_ops, &mptcp_pm_list, list) {

		if (!strcmp(pm_ops->name, name))

			return pm_ops;

	}



	return NULL;

}



int mptcp_pm_validate(struct mptcp_pm_ops *pm_ops)

{

	return 0;

}



int mptcp_pm_register(struct mptcp_pm_ops *pm_ops)

{

	int ret;



	ret = mptcp_pm_validate(pm_ops);

	if (ret)

		return ret;



	spin_lock(&mptcp_pm_list_lock);

	if (mptcp_pm_find(pm_ops->name)) {

		spin_unlock(&mptcp_pm_list_lock);

		return -EEXIST;

	}

	list_add_tail_rcu(&pm_ops->list, &mptcp_pm_list);

	spin_unlock(&mptcp_pm_list_lock);



	pr_debug("%s registered\n", pm_ops->name);

	return 0;

}



void mptcp_pm_unregister(struct mptcp_pm_ops *pm_ops)

{

	spin_lock(&mptcp_pm_list_lock);

	list_del_rcu(&pm_ops->list);

	spin_unlock(&mptcp_pm_list_lock);

}

net/mptcp/protocol.h

+5 −0
Original line number Diff line number Diff line
@@ -1050,6 +1050,11 @@ int mptcp_pm_remove_addr(struct mptcp_sock *msk, const struct mptcp_rm_list *rm_ 
void mptcp_pm_remove_addr_entry(struct mptcp_sock *msk,

				struct mptcp_pm_addr_entry *entry);



struct mptcp_pm_ops *mptcp_pm_find(const char *name);

int mptcp_pm_register(struct mptcp_pm_ops *pm_ops);

void mptcp_pm_unregister(struct mptcp_pm_ops *pm_ops);

int mptcp_pm_validate(struct mptcp_pm_ops *pm_ops);



void mptcp_userspace_pm_free_local_addr_list(struct mptcp_sock *msk);



void mptcp_event(enum mptcp_event_type type, const struct mptcp_sock *msk,