mptcp: sysctl: map pm_type to path_manager

This patch adds a new proc_handler "proc_pm_type" for "pm_type" to
map old path manager sysctl "pm_type" to the newly added "path_manager".

	path_manager		   pm_type

	MPTCP_PM_TYPE_KERNEL    -> "kernel"
	MPTCP_PM_TYPE_USERSPACE -> "userspace"

It is important to add this to keep a compatibility with the now
deprecated pm_type sysctl knob.

Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250313-net-next-mptcp-pm-ops-intro-v1-10-f4e4a88efc50@kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

diff --git a/net/mptcp/ctrl.c b/net/mptcp/ctrl.c
index cb0811e636ff2f4bb981d2688eb8d07946fc1744..4d8b31f32eb50347d10db792f084e43c93f687c6 100644 (file)
--- a/net/mptcp/ctrl.c
+++ b/net/mptcp/ctrl.c
@@ -230,6 +230,29 @@ static int proc_path_manager(const struct ctl_table *ctl, int write,
        return ret;
 }
 
+static int proc_pm_type(const struct ctl_table *ctl, int write,
+                       void *buffer, size_t *lenp, loff_t *ppos)
+{
+       struct mptcp_pernet *pernet = container_of(ctl->data,
+                                                  struct mptcp_pernet,
+                                                  pm_type);
+       int ret;
+
+       ret = proc_dou8vec_minmax(ctl, write, buffer, lenp, ppos);
+       if (write && ret == 0) {
+               u8 pm_type = READ_ONCE(*(u8 *)ctl->data);
+               char *pm_name = "";
+
+               if (pm_type == MPTCP_PM_TYPE_KERNEL)
+                       pm_name = "kernel";
+               else if (pm_type == MPTCP_PM_TYPE_USERSPACE)
+                       pm_name = "userspace";
+               mptcp_set_path_manager(pernet->path_manager, pm_name);
+       }
+
+       return ret;
+}
+
 static struct ctl_table mptcp_sysctl_table[] = {
        {
                .procname = "enabled",
@@ -274,7 +297,7 @@ static struct ctl_table mptcp_sysctl_table[] = {
                .procname = "pm_type",
                .maxlen = sizeof(u8),
                .mode = 0644,
-               .proc_handler = proc_dou8vec_minmax,
+               .proc_handler = proc_pm_type,
                .extra1       = SYSCTL_ZERO,
                .extra2       = &mptcp_pm_type_max
        },