Series comparison

-[PATCH mptcp-next v1 0/5] BPF path manager, part 5
+[PATCH mptcp-next v1 0/9] BPF path manager, part 5
 From: Geliang Tang <tanggeliang@kylinos.cn>
+Implement address_announced/address_removed/subflow_established/
+subflow_closed interfaces.
 Depends on:
+ - BPF path manager, part 4, v5
+Based-on: <cover.1740019794.git.tanggeliang@kylinos.cn>
- - BPF path manager, part 4, v4
+Geliang Tang (9):
-Based-on: <cover.1738919954.git.tanggeliang@kylinos.cn>
+  mptcp: pm: in-kernel: add address_removed/subflow_closed
   mptcp: pm: in-kernel: address_announced interface
   mptcp: pm: in-kernel: address_removed interface
   mptcp: pm: in-kernel: subflow_established interface
   mptcp: pm: in-kernel: subflow_closed interface
   mptcp: pm: userspace: address_announced interface
   mptcp: pm: userspace: address_removed interface
   mptcp: pm: userspace: subflow_established interface
   mptcp: pm: userspace: subflow_closed interface
- - add mptcp_address bpf_iter, v5
+ net/mptcp/pm_netlink.c   | 115 ++++++++++++++------
-Based-on: <cover.1738924354.git.tanggeliang@kylinos.cn>
+ net/mptcp/pm_userspace.c | 220 +++++++++++++++++++++++----------------
+files changed, 215 insertions(+), 120 deletions(-)
 Geliang Tang (5):
   bpf: Add mptcp path manager struct_ops
   bpf: Register mptcp struct_ops kfunc set
   selftests/bpf: Add mptcp userspace pm subtest
   selftests/bpf: Implement mptcp pm helpers in BPF
   selftests/bpf: Add mptcp bpf path manager subtest
  net/mptcp/bpf.c                               | 372 +++++++++++++++++-
  .../testing/selftests/bpf/prog_tests/mptcp.c  | 211 ++++++++++
  tools/testing/selftests/bpf/progs/mptcp_bpf.h | 185 +++++++++
  .../bpf/progs/mptcp_bpf_userspace_pm.c        | 275 +++++++++++++
 files changed, 1042 insertions(+), 1 deletion(-)
  create mode 100644 tools/testing/selftests/bpf/progs/mptcp_bpf_userspace_pm.c
 --
 .43.0

-[PATCH mptcp-next v1 3/5] selftests/bpf: Add mptcp userspace pm subtest
+[PATCH mptcp-next v1 1/9] mptcp: pm: in-kernel: add address_removed/subflow_closed
 From: Geliang Tang <tanggeliang@kylinos.cn>
-To verify that the behavior of BPF path manager is the same as that of
+This patch defines the code in the loop of traversing all msks in
-userspace pm in the kernel, a userspace pm self-test has been added.
+mptcp_nl_remove_subflow_and_signal_addr() as two new helpers,
-BPF path manager in the next commit will also use this test.
+mptcp_pm_nl_address_removed() and mptcp_pm_nl_subflow_closed(),
 used for signaling a RM_ADDR and closing a subflow respectively.
 Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
 ---
- .../testing/selftests/bpf/prog_tests/mptcp.c  | 160 ++++++++++++++++++
+ net/mptcp/pm_netlink.c | 60 +++++++++++++++++++++++++++---------------
-file changed, 160 insertions(+)
+file changed, 39 insertions(+), 21 deletions(-)
-diff --git a/tools/testing/selftests/bpf/prog_tests/mptcp.c b/tools/testing/selftests/bpf/prog_tests/mptcp.c
+diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c
 index XXXXXXX..XXXXXXX 100644
---- a/tools/testing/selftests/bpf/prog_tests/mptcp.c
+--- a/net/mptcp/pm_netlink.c
-+++ b/tools/testing/selftests/bpf/prog_tests/mptcp.c
++++ b/net/mptcp/pm_netlink.c
-@@ -XXX,XX +XXX,XX @@ enum mptcp_pm_type {
+@@ -XXX,XX +XXX,XX @@ static void __mark_subflow_endp_available(struct mptcp_sock *msk, u8 id)
-     __MPTCP_PM_TYPE_MAX = __MPTCP_PM_TYPE_NR - 1,
+         msk->pm.local_addr_used--;
- };
+ }
-+enum mptcp_pm_family {
++static int mptcp_pm_nl_address_removed(struct mptcp_sock *msk,
-+    IPV4 = 0,
++                       const struct mptcp_pm_addr_entry *local)
-+    IPV4MAPPED,
++{
-+    IPV6,
++    bool remove_subflow;
 +};
 +
- static const unsigned int total_bytes = 10 * 1024 * 1024;
++    remove_subflow = mptcp_lookup_subflow_by_saddr(&msk->conn_list, &local->addr);
- static int duration;
++    mptcp_pm_remove_anno_addr(msk, &local->addr, remove_subflow &&
++                  !(local->flags & MPTCP_PM_ADDR_FLAG_IMPLICIT));
-@@ -XXX,XX +XXX,XX @@ static void test_iters_address(void)
++    return 0;
      close(cgroup_fd);
  }
 +static int userspace_pm_add_addr(__u32 token, char *addr, __u8 id)
 +{
 +    return SYS_NOFAIL("ip netns exec %s %s ann %s id %u token %u",
 +              NS_TEST, PM_CTL, addr, id, token);
 +}
 +
-+static int userspace_pm_rm_addr(__u32 token, __u8 id)
++static int mptcp_pm_nl_subflow_closed(struct mptcp_sock *msk,
 +                      const struct mptcp_pm_addr_entry *local)
 +{
-+    return SYS_NOFAIL("ip netns exec %s %s rem id %u token %u",
++    struct mptcp_rm_list list = { .nr = 1 };
-+              NS_TEST, PM_CTL, id, token);
++    bool remove_subflow;
 +
 +    list.ids[0] = mptcp_endp_get_local_id(msk, &local->addr);
 +    remove_subflow = mptcp_lookup_subflow_by_saddr(&msk->conn_list, &local->addr);
 +    if (remove_subflow) {
 +        spin_lock_bh(&msk->pm.lock);
 +        mptcp_pm_nl_rm_subflow_received(msk, &list);
 +        spin_unlock_bh(&msk->pm.lock);
 +    }
 +
 +    if (local->flags & MPTCP_PM_ADDR_FLAG_SUBFLOW) {
 +        spin_lock_bh(&msk->pm.lock);
 +        __mark_subflow_endp_available(msk, list.ids[0]);
 +        spin_unlock_bh(&msk->pm.lock);
 +    }
 +
 +    if (msk->mpc_endpoint_id == local->addr.id)
 +        msk->mpc_endpoint_id = 0;
 +
 +    return 0;
 +}
 +
-+static int userspace_pm_rm_subflow(__u32 token, char *addr, __u8 id)
+ static int mptcp_nl_remove_subflow_and_signal_addr(struct net *net,
-+{
+                            const struct mptcp_pm_addr_entry *entry)
 +    bool ipv6 = strstr(addr, ":");
 +    char line[1024], *str;
 +    __u32 sport, dport;
 +
 +    if (userspace_pm_get_events_line("type:10", line))
 +        return -1;
 +
 +    str = strstr(line, "sport");
 +    if (!str || sscanf(str, "sport:%u,dport:%u,", &sport, &dport) != 2) {
 +        log_err("rm_subflow error, str=%s\n", str);
 +        return -1;
 +    }
 +
 +    str = ipv6 ? (strstr(addr, ".") ? "::ffff:"ADDR_1 : ADDR6_1) : ADDR_1;
 +    return SYS_NOFAIL("ip netns exec %s %s dsf lip %s lport %u rip %s rport %u token %u",
 +              NS_TEST, PM_CTL, addr, sport, str, dport, token);
 +}
 +
 +static int userspace_pm_set_flags(__u32 token, char *addr, char *flags)
 +{
 +    bool ipv6 = strstr(addr, ":");
 +    char line[1024], *str;
 +    __u32 sport, dport;
 +
 +    if (userspace_pm_get_events_line("type:10", line))
 +        return -1;
 +
 +    str = strstr(line, "sport");
 +    if (!str || sscanf(str, "sport:%u,dport:%u,", &sport, &dport) != 2) {
 +        log_err("set_flags error, str=%s\n", str);
 +        return -1;
 +    }
 +
 +    str = ipv6 ? (strstr(addr, ".") ? "::ffff:"ADDR_1 : ADDR6_1) : ADDR_1;
 +    return SYS_NOFAIL("ip netns exec %s %s set %s port %u rip %s rport %u flags %s token %u",
 +              NS_TEST, PM_CTL, addr, sport, str, dport, flags, token);
 +}
 +
 +static void run_userspace_pm(enum mptcp_pm_family family)
 +{
 +    bool ipv4mapped = (family == IPV4MAPPED);
 +    bool ipv6 = (family == IPV6 || ipv4mapped);
 +    int server_fd, client_fd, accept_fd;
 +    __u32 token;
 +    char *addr;
 +    int err;
 +
 +    addr = ipv6 ? (ipv4mapped ? "::ffff:"ADDR_1 : ADDR6_1) : ADDR_1;
 +    server_fd = start_mptcp_server(ipv6 ? AF_INET6 : AF_INET, addr, PORT_1, 0);
 +    if (!ASSERT_OK_FD(server_fd, "start_mptcp_server"))
 +        return;
 +
 +    client_fd = connect_to_fd(server_fd, 0);
 +    if (!ASSERT_OK_FD(client_fd, "connect_to_fd"))
 +        goto close_server;
 +
 +    accept_fd = accept(server_fd, NULL, NULL);
 +    if (!ASSERT_OK_FD(accept_fd, "accept"))
 +        goto close_client;
 +
 +    token = userspace_pm_get_token(client_fd);
 +    if (!token)
 +        goto close_client;
 +    recv_byte(accept_fd);
 +    usleep(200000); /* 0.2s */
 +
 +    addr = ipv6 ? (ipv4mapped ? "::ffff:"ADDR_2 : ADDR6_2) : ADDR_2;
 +    err = userspace_pm_add_subflow(token, addr, 100);
 +    if (!ASSERT_OK(err, "userspace_pm_add_subflow 100"))
 +        goto close_accept;
 +
 +    send_byte(accept_fd);
 +    recv_byte(client_fd);
 +
 +    err = userspace_pm_set_flags(token, addr, "backup");
 +    if (!ASSERT_OK(err, "userspace_pm_set_flags backup"))
 +        goto close_accept;
 +
 +    send_byte(client_fd);
 +    recv_byte(accept_fd);
 +
 +    err = userspace_pm_set_flags(token, addr, "nobackup");
 +    if (!ASSERT_OK(err, "userspace_pm_set_flags nobackup"))
 +        goto close_accept;
 +
 +    send_byte(accept_fd);
 +    recv_byte(client_fd);
 +
 +    err = userspace_pm_rm_subflow(token, addr, 100);
 +    if (!ASSERT_OK(err, "userspace_pm_rm_subflow 100"))
 +        goto close_accept;
 +
 +    send_byte(client_fd);
 +    recv_byte(accept_fd);
 +
 +    addr = ipv6 ? (ipv4mapped ? "::ffff:"ADDR_3 : ADDR6_3) : ADDR_3;
 +    err = userspace_pm_add_addr(token, addr, 200);
 +    if (!ASSERT_OK(err, "userspace_pm_add_addr 200"))
 +        goto close_accept;
 +
 +    send_byte(accept_fd);
 +    recv_byte(client_fd);
 +
 +    err = userspace_pm_rm_addr(token, 200);
 +    if (!ASSERT_OK(err, "userspace_pm_rm_addr 200"))
 +        goto close_accept;
 +
 +    send_byte(client_fd);
 +    recv_byte(accept_fd);
 +
 +close_accept:
 +    close(accept_fd);
 +close_client:
 +    close(client_fd);
 +close_server:
 +    close(server_fd);
 +}
 +
 +static void test_userspace_pm(void)
 +{
 +    struct netns_obj *netns;
 +    int err;
 +
 +    netns = netns_new(NS_TEST, true);
 +    if (!ASSERT_OK_PTR(netns, "netns_new"))
 +        return;
 +
 +    err = userspace_pm_init(MPTCP_PM_TYPE_USERSPACE);
 +    if (!ASSERT_OK(err, "userspace_pm_init: userspace pm"))
 +        goto fail;
 +
 +    run_userspace_pm(IPV4MAPPED);
 +
 +    userspace_pm_cleanup();
 +fail:
 +    netns_free(netns);
 +}
 +
  static struct netns_obj *sched_init(char *flags, char *sched)
  {
-     struct netns_obj *netns;
+     const struct mptcp_addr_info *addr = &entry->addr;
-@@ -XXX,XX +XXX,XX @@ void test_mptcp(void)
+-    struct mptcp_rm_list list = { .nr = 1 };
-         test_iters_subflow();
+     long s_slot = 0, s_num = 0;
-     if (test__start_subtest("iters_address"))
+     struct mptcp_sock *msk;
-         test_iters_address();
-+    if (test__start_subtest("userspace_pm"))
+@@ -XXX,XX +XXX,XX @@ static int mptcp_nl_remove_subflow_and_signal_addr(struct net *net,
-+        test_userspace_pm();
-     if (test__start_subtest("default"))
+     while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) {
-         test_default();
+         struct sock *sk = (struct sock *)msk;
-     if (test__start_subtest("first"))
+-        bool remove_subflow;
          if (mptcp_pm_is_userspace(msk))
              goto next;
          lock_sock(sk);
 -        remove_subflow = mptcp_lookup_subflow_by_saddr(&msk->conn_list, addr);
 -        mptcp_pm_remove_anno_addr(msk, addr, remove_subflow &&
 -                      !(entry->flags & MPTCP_PM_ADDR_FLAG_IMPLICIT));
 -
 -        list.ids[0] = mptcp_endp_get_local_id(msk, addr);
 -        if (remove_subflow) {
 -            spin_lock_bh(&msk->pm.lock);
 -            mptcp_pm_nl_rm_subflow_received(msk, &list);
 -            spin_unlock_bh(&msk->pm.lock);
 -        }
 -
 -        if (entry->flags & MPTCP_PM_ADDR_FLAG_SUBFLOW) {
 -            spin_lock_bh(&msk->pm.lock);
 -            __mark_subflow_endp_available(msk, list.ids[0]);
 -            spin_unlock_bh(&msk->pm.lock);
 -        }
 -
 -        if (msk->mpc_endpoint_id == entry->addr.id)
 -            msk->mpc_endpoint_id = 0;
 +        mptcp_pm_nl_address_removed(msk, entry);
 +        mptcp_pm_nl_subflow_closed(msk, entry);
          release_sock(sk);
  next:
 --
 .43.0

-New patch
+[PATCH mptcp-next v1 2/9] mptcp: pm: in-kernel: address_announced interface
+From: Geliang Tang <tanggeliang@kylinos.cn>
+Extract address_announced() interface of the in-kernel netlink PM from
+the helper mptcp_nl_add_subflow_or_signal_addr(), only leave the code
+for traversing all msk in the helper.
+This interface is invoked under holding the msk socket lock.
+Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
+---
+ net/mptcp/pm_netlink.c | 34 +++++++++++++++++++++++++---------
+file changed, 25 insertions(+), 9 deletions(-)
+diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c
+index XXXXXXX..XXXXXXX 100644
+--- a/net/mptcp/pm_netlink.c
++++ b/net/mptcp/pm_netlink.c
+@@ -XXX,XX +XXX,XX @@ static struct pm_nl_pernet *genl_info_pm_nl(struct genl_info *info)
+     return pm_nl_get_pernet(genl_info_net(info));
+ }
++static int mptcp_pm_nl_address_announced(struct mptcp_sock *msk,
++                     struct mptcp_pm_param *param)
++{
++    struct mptcp_addr_info *addr = &param->addr;
++    struct mptcp_addr_info mpc_addr;
++
++    /* if the endp linked to the init sf is re-added with a != ID */
++    mptcp_local_address((struct sock_common *)msk, &mpc_addr);
++
++    spin_lock_bh(&msk->pm.lock);
++    if (mptcp_addresses_equal(addr, &mpc_addr, addr->port))
++        msk->mpc_endpoint_id = addr->id;
++
++    mptcp_pm_create_subflow_or_signal_addr(msk);
++    spin_unlock_bh(&msk->pm.lock);
++
++    return 0;
++}
++
+ static int mptcp_nl_add_subflow_or_signal_addr(struct net *net,
+                            struct mptcp_addr_info *addr)
+ {
+@@ -XXX,XX +XXX,XX @@ static int mptcp_nl_add_subflow_or_signal_addr(struct net *net,
+     while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) {
+         struct sock *sk = (struct sock *)msk;
+-        struct mptcp_addr_info mpc_addr;
++        struct mptcp_pm_param param;
+         if (!READ_ONCE(msk->fully_established) ||
+             mptcp_pm_is_userspace(msk))
+             goto next;
+-        /* if the endp linked to the init sf is re-added with a != ID */
+-        mptcp_local_address((struct sock_common *)msk, &mpc_addr);
+-
+         lock_sock(sk);
+-        spin_lock_bh(&msk->pm.lock);
+-        if (mptcp_addresses_equal(addr, &mpc_addr, addr->port))
+-            msk->mpc_endpoint_id = addr->id;
+-        mptcp_pm_create_subflow_or_signal_addr(msk);
+-        spin_unlock_bh(&msk->pm.lock);
++        mptcp_pm_param_set_contexts(&param, NULL, addr);
++        msk->pm.ops && msk->pm.ops->address_announced ?
++            msk->pm.ops->address_announced(msk, &param) :
++            mptcp_pm_nl_address_announced(msk, &param);
+         release_sock(sk);
+ next:
+@@ -XXX,XX +XXX,XX @@ static struct pernet_operations mptcp_pm_pernet_ops = {
+ };
+ static struct mptcp_pm_ops mptcp_netlink_pm = {
++    .address_announced    = mptcp_pm_nl_address_announced,
+     .get_local_id        = mptcp_pm_nl_get_local_id,
+     .get_priority        = mptcp_pm_nl_get_priority,
+     .type            = MPTCP_PM_TYPE_KERNEL,
+--
+.43.0

-New patch
+[PATCH mptcp-next v1 3/9] mptcp: pm: in-kernel: address_removed interface
+From: Geliang Tang <tanggeliang@kylinos.cn>
+Update the 2nd parameter of mptcp_pm_nl_address_removed(), and define it
+as the address_removed() interface of the in-kernel netlink PM.
+This interface is invoked under holding the msk socket lock.
+Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
+---
+ net/mptcp/pm_netlink.c | 10 ++++++++--
+file changed, 8 insertions(+), 2 deletions(-)
+diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c
+index XXXXXXX..XXXXXXX 100644
+--- a/net/mptcp/pm_netlink.c
++++ b/net/mptcp/pm_netlink.c
+@@ -XXX,XX +XXX,XX @@ static void __mark_subflow_endp_available(struct mptcp_sock *msk, u8 id)
+ }
+ static int mptcp_pm_nl_address_removed(struct mptcp_sock *msk,
+-                       const struct mptcp_pm_addr_entry *local)
++                       struct mptcp_pm_param *param)
+ {
++    struct mptcp_pm_addr_entry *local = &param->entry;
+     bool remove_subflow;
+     remove_subflow = mptcp_lookup_subflow_by_saddr(&msk->conn_list, &local->addr);
+@@ -XXX,XX +XXX,XX @@ static int mptcp_nl_remove_subflow_and_signal_addr(struct net *net,
+     while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) {
+         struct sock *sk = (struct sock *)msk;
++        struct mptcp_pm_param param;
+         if (mptcp_pm_is_userspace(msk))
+             goto next;
+         lock_sock(sk);
+-        mptcp_pm_nl_address_removed(msk, entry);
++        mptcp_pm_param_set_contexts(&param, entry, NULL);
++        msk->pm.ops && msk->pm.ops->address_removed ?
++            msk->pm.ops->address_removed(msk, &param) :
++            mptcp_pm_nl_address_removed(msk, &param);
+         mptcp_pm_nl_subflow_closed(msk, entry);
+         release_sock(sk);
+@@ -XXX,XX +XXX,XX @@ static struct pernet_operations mptcp_pm_pernet_ops = {
+ static struct mptcp_pm_ops mptcp_netlink_pm = {
+     .address_announced    = mptcp_pm_nl_address_announced,
++    .address_removed    = mptcp_pm_nl_address_removed,
+     .get_local_id        = mptcp_pm_nl_get_local_id,
+     .get_priority        = mptcp_pm_nl_get_priority,
+     .type            = MPTCP_PM_TYPE_KERNEL,
+--
+.43.0

-New patch
+[PATCH mptcp-next v1 4/9] mptcp: pm: in-kernel: subflow_established interface
+From: Geliang Tang <tanggeliang@kylinos.cn>
+Update mptcp_pm_nl_subflow_established() to match the parameters and
+return value of subflow_established() interface and define it as the
+interface of the in-kernel netlink PM.
+This interface is invoked under holding the msk socket lock.
+Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
+---
+ net/mptcp/pm_netlink.c | 11 +++++++++--
+file changed, 9 insertions(+), 2 deletions(-)
+diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c
+index XXXXXXX..XXXXXXX 100644
+--- a/net/mptcp/pm_netlink.c
++++ b/net/mptcp/pm_netlink.c
+@@ -XXX,XX +XXX,XX @@ static void mptcp_pm_nl_fully_established(struct mptcp_sock *msk)
+     mptcp_pm_create_subflow_or_signal_addr(msk);
+ }
+-static void mptcp_pm_nl_subflow_established(struct mptcp_sock *msk)
++static int mptcp_pm_nl_subflow_established(struct mptcp_sock *msk,
++                       struct mptcp_pm_param *param)
+ {
+     mptcp_pm_create_subflow_or_signal_addr(msk);
++
++    return 0;
+ }
+ /* Fill all the local addresses into the array addrs[],
+@@ -XXX,XX +XXX,XX @@ static void mptcp_pm_nl_rm_subflow_received(struct mptcp_sock *msk,
+ void mptcp_pm_nl_work(struct mptcp_sock *msk)
+ {
+     struct mptcp_pm_data *pm = &msk->pm;
++    struct mptcp_pm_param param;
+     msk_owned_by_me(msk);
+@@ -XXX,XX +XXX,XX @@ void mptcp_pm_nl_work(struct mptcp_sock *msk)
+     }
+     if (pm->status & BIT(MPTCP_PM_SUBFLOW_ESTABLISHED)) {
+         pm->status &= ~BIT(MPTCP_PM_SUBFLOW_ESTABLISHED);
+-        mptcp_pm_nl_subflow_established(msk);
++        msk->pm.ops && msk->pm.ops->subflow_established ?
++            msk->pm.ops->subflow_established(msk, &param) :
++            mptcp_pm_nl_subflow_established(msk, &param);
+     }
+     spin_unlock_bh(&msk->pm.lock);
+@@ -XXX,XX +XXX,XX @@ static struct pernet_operations mptcp_pm_pernet_ops = {
+ static struct mptcp_pm_ops mptcp_netlink_pm = {
+     .address_announced    = mptcp_pm_nl_address_announced,
+     .address_removed    = mptcp_pm_nl_address_removed,
++    .subflow_established    = mptcp_pm_nl_subflow_established,
+     .get_local_id        = mptcp_pm_nl_get_local_id,
+     .get_priority        = mptcp_pm_nl_get_priority,
+     .type            = MPTCP_PM_TYPE_KERNEL,
+--
+.43.0

-New patch
+[PATCH mptcp-next v1 5/9] mptcp: pm: in-kernel: subflow_closed interface
+From: Geliang Tang <tanggeliang@kylinos.cn>
+Update the 2nd parameter of mptcp_pm_nl_subflow_closed(), and define it
+as the subflow_closed() interface of the in-kernel netlink PM.
+This interface is invoked under holding the msk socket lock.
+Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
+---
+ net/mptcp/pm_netlink.c | 8 ++++++--
+file changed, 6 insertions(+), 2 deletions(-)
+diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c
+index XXXXXXX..XXXXXXX 100644
+--- a/net/mptcp/pm_netlink.c
++++ b/net/mptcp/pm_netlink.c
+@@ -XXX,XX +XXX,XX @@ static int mptcp_pm_nl_address_removed(struct mptcp_sock *msk,
+ }
+ static int mptcp_pm_nl_subflow_closed(struct mptcp_sock *msk,
+-                      const struct mptcp_pm_addr_entry *local)
++                      struct mptcp_pm_param *param)
+ {
++    struct mptcp_pm_addr_entry *local = &param->entry;
+     struct mptcp_rm_list list = { .nr = 1 };
+     bool remove_subflow;
+@@ -XXX,XX +XXX,XX @@ static int mptcp_nl_remove_subflow_and_signal_addr(struct net *net,
+         msk->pm.ops && msk->pm.ops->address_removed ?
+             msk->pm.ops->address_removed(msk, &param) :
+             mptcp_pm_nl_address_removed(msk, &param);
+-        mptcp_pm_nl_subflow_closed(msk, entry);
++        msk->pm.ops && msk->pm.ops->subflow_closed ?
++            msk->pm.ops->subflow_closed(msk, &param) :
++            mptcp_pm_nl_subflow_closed(msk, &param);
+         release_sock(sk);
+ next:
+@@ -XXX,XX +XXX,XX @@ static struct mptcp_pm_ops mptcp_netlink_pm = {
+     .address_announced    = mptcp_pm_nl_address_announced,
+     .address_removed    = mptcp_pm_nl_address_removed,
+     .subflow_established    = mptcp_pm_nl_subflow_established,
++    .subflow_closed        = mptcp_pm_nl_subflow_closed,
+     .get_local_id        = mptcp_pm_nl_get_local_id,
+     .get_priority        = mptcp_pm_nl_get_priority,
+     .type            = MPTCP_PM_TYPE_KERNEL,
+--
+.43.0

-[PATCH mptcp-next v1 5/5] selftests/bpf: Add mptcp bpf path manager subtest
+[PATCH mptcp-next v1 6/9] mptcp: pm: userspace: address_announced interface
 From: Geliang Tang <tanggeliang@kylinos.cn>
-This patch adds an mptcp bpf userspace pm example program, implements
+Extract address_announced() interface of the userspace PM from the handler
-address_announce, address_remove, subflow_create, subflow_destroy,
+of netlink command MPTCP_PM_CMD_ANNOUNCE mptcp_pm_nl_announce_doit(), only
-get_local_id, is_backup, and set_flags interfaces using almost the
+leave the code for obtaining msk through "info" and parsing address entry
-same logic as the userspace pm in kernel.
+in the handler.
 This interface is invoked under holding the msk socket lock.
 Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
 ---
- .../testing/selftests/bpf/prog_tests/mptcp.c  |  51 ++++
+ net/mptcp/pm_userspace.c | 49 ++++++++++++++++++++++++++--------------
- tools/testing/selftests/bpf/progs/mptcp_bpf.h |  75 +++++
+file changed, 32 insertions(+), 17 deletions(-)
  .../bpf/progs/mptcp_bpf_userspace_pm.c        | 275 ++++++++++++++++++
 files changed, 401 insertions(+)
  create mode 100644 tools/testing/selftests/bpf/progs/mptcp_bpf_userspace_pm.c
-diff --git a/tools/testing/selftests/bpf/prog_tests/mptcp.c b/tools/testing/selftests/bpf/prog_tests/mptcp.c
+diff --git a/net/mptcp/pm_userspace.c b/net/mptcp/pm_userspace.c
 index XXXXXXX..XXXXXXX 100644
---- a/tools/testing/selftests/bpf/prog_tests/mptcp.c
+--- a/net/mptcp/pm_userspace.c
-+++ b/tools/testing/selftests/bpf/prog_tests/mptcp.c
++++ b/net/mptcp/pm_userspace.c
-@@ -XXX,XX +XXX,XX @@
+@@ -XXX,XX +XXX,XX @@ static struct mptcp_sock *mptcp_userspace_pm_get_sock(const struct genl_info *in
- #include "mptcpify.skel.h"
+     return msk;
  #include "mptcp_subflow.skel.h"
  #include "mptcp_bpf_iters.skel.h"
 +#include "mptcp_bpf_userspace_pm.skel.h"
  #include "mptcp_bpf_first.skel.h"
  #include "mptcp_bpf_bkup.skel.h"
  #include "mptcp_bpf_rr.skel.h"
@@ -XXX,XX +XXX,XX @@
  enum mptcp_pm_type {
      MPTCP_PM_TYPE_KERNEL = 0,
      MPTCP_PM_TYPE_USERSPACE,
 +    MPTCP_PM_TYPE_BPF_USERSPACE,
      __MPTCP_PM_TYPE_NR,
      __MPTCP_PM_TYPE_MAX = __MPTCP_PM_TYPE_NR - 1,
@@ -XXX,XX +XXX,XX @@ static void test_userspace_pm(void)
      netns_free(netns);
  }
-+static void test_bpf_path_manager(void)
++static int mptcp_userspace_pm_address_announced(struct mptcp_sock *msk,
 +                        struct mptcp_pm_param *param)
 +{
-+    struct mptcp_bpf_userspace_pm *skel;
++    struct mptcp_pm_addr_entry *local = &param->entry;
 +    struct netns_obj *netns;
 +    int err;
 +
 +    skel = mptcp_bpf_userspace_pm__open();
 +    if (!ASSERT_OK_PTR(skel, "open: userspace_pm"))
 +        return;
 +
 +    err = bpf_program__set_flags(skel->progs.mptcp_userspace_pm_address_announced,
 +                     BPF_F_SLEEPABLE);
 +    err = err ?: bpf_program__set_flags(skel->progs.mptcp_userspace_pm_address_removed,
 +                        BPF_F_SLEEPABLE);
 +    err = err ?: bpf_program__set_flags(skel->progs.mptcp_userspace_pm_subflow_established,
 +                        BPF_F_SLEEPABLE);
 +    err = err ?: bpf_program__set_flags(skel->progs.mptcp_userspace_pm_subflow_closed,
 +                        BPF_F_SLEEPABLE);
 +    err = err ?: bpf_program__set_flags(skel->progs.mptcp_userspace_pm_set_priority,
 +                        BPF_F_SLEEPABLE);
 +    if (!ASSERT_OK(err, "set sleepable flags"))
 +        goto skel_destroy;
 +
 +    if (!ASSERT_OK(mptcp_bpf_userspace_pm__load(skel), "load: userspace_pm"))
 +        goto skel_destroy;
 +
 +    err = mptcp_bpf_userspace_pm__attach(skel);
 +    if (!ASSERT_OK(err, "attach: userspace_pm"))
 +        goto skel_destroy;
 +
 +    netns = netns_new(NS_TEST, true);
 +    if (!ASSERT_OK_PTR(netns, "netns_new"))
 +        goto skel_destroy;
 +
 +    err = userspace_pm_init(MPTCP_PM_TYPE_BPF_USERSPACE);
 +    if (!ASSERT_OK(err, "userspace_pm_init: bpf pm"))
 +        goto close_netns;
 +
 +    run_userspace_pm(skel->kconfig->CONFIG_MPTCP_IPV6 ? IPV6 : IPV4);
 +
 +    userspace_pm_cleanup();
 +close_netns:
 +    netns_free(netns);
 +skel_destroy:
 +    mptcp_bpf_userspace_pm__destroy(skel);
 +}
 +
  static struct netns_obj *sched_init(char *flags, char *sched)
  {
      struct netns_obj *netns;
@@ -XXX,XX +XXX,XX @@ void test_mptcp(void)
          test_iters_address();
      if (test__start_subtest("userspace_pm"))
          test_userspace_pm();
 +    if (test__start_subtest("bpf_path_manager"))
 +        test_bpf_path_manager();
      if (test__start_subtest("default"))
          test_default();
      if (test__start_subtest("first"))
 diff --git a/tools/testing/selftests/bpf/progs/mptcp_bpf.h b/tools/testing/selftests/bpf/progs/mptcp_bpf.h
 index XXXXXXX..XXXXXXX 100644
 --- a/tools/testing/selftests/bpf/progs/mptcp_bpf.h
 +++ b/tools/testing/selftests/bpf/progs/mptcp_bpf.h
@@ -XXX,XX +XXX,XX @@ static inline int list_is_head(const struct list_head *list,
  #define    ENOMEM        12    /* Out of Memory */
  #define    EINVAL        22    /* Invalid argument */
 +/* mptcp helpers from include/net/mptcp.h */
 +#define U8_MAX        ((u8)~0U)
 +
 +/* max value of mptcp_addr_info.id */
 +#define MPTCP_PM_MAX_ADDR_ID        U8_MAX
 +
 +/* mptcp macros from include/uapi/linux/mptcp.h */
 +#define MPTCP_PM_ADDR_FLAG_SIGNAL            (1 << 0)
 +#define MPTCP_PM_ADDR_FLAG_SUBFLOW            (1 << 1)
 +#define MPTCP_PM_ADDR_FLAG_BACKUP            (1 << 2)
 +#define MPTCP_PM_ADDR_FLAG_FULLMESH            (1 << 3)
 +#define MPTCP_PM_ADDR_FLAG_IMPLICIT            (1 << 4)
 +
 +/* address families macros from include/linux/socket.h */
 +#define AF_UNSPEC    0
 +#define AF_INET        2
 +#define AF_INET6    10
 +
 +/* shutdown macros from include/net/sock.h */
 +#define RCV_SHUTDOWN    1
 +#define SEND_SHUTDOWN    2
 +
 +/* GFP macros from include/linux/gfp_types.h */
 +#define __AC(X,Y)    (X##Y)
 +#define _AC(X,Y)    __AC(X,Y)
 +#define _UL(x)        (_AC(x, UL))
 +#define UL(x)        (_UL(x))
 +#define BIT(nr)        (UL(1) << (nr))
 +
 +#define ___GFP_HIGH        BIT(___GFP_HIGH_BIT)
 +#define __GFP_HIGH        ((gfp_t)___GFP_HIGH)
 +#define ___GFP_KSWAPD_RECLAIM    BIT(___GFP_KSWAPD_RECLAIM_BIT)
 +#define __GFP_KSWAPD_RECLAIM    ((gfp_t)___GFP_KSWAPD_RECLAIM) /* kswapd can wake */
 +#define GFP_ATOMIC        (__GFP_HIGH|__GFP_KSWAPD_RECLAIM)
 +
  static __always_inline struct sock *
  mptcp_subflow_tcp_sock(const struct mptcp_subflow_context *subflow)
  {
@@ -XXX,XX +XXX,XX @@ extern void bpf_spin_unlock_bh(spinlock_t *lock) __ksym;
  extern bool bpf_ipv4_is_private_10(__be32 addr) __ksym;
 +extern struct mptcp_pm_addr_entry *
 +bpf_sock_kmalloc_entry(struct sock *sk, int size, gfp_t priority) __ksym;
 +extern void
 +bpf_sock_kfree_entry(struct sock *sk, struct mptcp_pm_addr_entry *entry,
 +             int size) __ksym;
 +
 +extern bool mptcp_pm_alloc_anno_list(struct mptcp_sock *msk,
 +                     const struct mptcp_addr_info *addr) __ksym;
 +extern int mptcp_pm_announce_addr(struct mptcp_sock *msk,
 +                  const struct mptcp_addr_info *addr,
 +                  bool echo) __ksym;
 +extern void mptcp_pm_nl_addr_send_ack(struct mptcp_sock *msk) __ksym;
 +
 +extern void bpf_bitmap_zero(unsigned long *dst, unsigned int nbits) __ksym;
 +extern void bpf_set_bit(unsigned long nr, unsigned long *addr) __ksym;
 +extern u8 bpf_find_next_zero_bit(const unsigned long *addr,
 +                 unsigned long size, unsigned long offset) __ksym;
 +
 +extern int mptcp_pm_remove_addr(struct mptcp_sock *msk,
 +                const struct mptcp_rm_list *rm_list) __ksym;
 +extern void mptcp_pm_remove_addr_entry(struct mptcp_sock *msk,
 +                       struct mptcp_pm_addr_entry *entry) __ksym;
 +
 +extern int bpf_mptcp_subflow_connect(struct sock *sk,
 +                     const struct mptcp_pm_addr_entry *entry,
 +                     const struct mptcp_addr_info *remote) __ksym;
 +
 +extern void
 +mptcp_subflow_shutdown(struct sock *sk, struct sock *ssk, int how) __ksym;
 +extern void mptcp_close_ssk(struct sock *sk, struct sock *ssk,
 +                struct mptcp_subflow_context *subflow) __ksym;
 +extern struct net *bpf_sock_net(const struct sock *sk) __ksym;
 +extern void BPF_MPTCP_INC_STATS(struct net *net,
 +                enum linux_mptcp_mib_field field) __ksym;
 +
 +extern int mptcp_pm_nl_mp_prio_send_ack(struct mptcp_sock *msk,
 +                    struct mptcp_addr_info *addr,
 +                    struct mptcp_addr_info *rem,
 +                    u8 bkup) __ksym;
 +
  extern void mptcp_subflow_set_scheduled(struct mptcp_subflow_context *subflow,
                      bool scheduled) __ksym;
 diff --git a/tools/testing/selftests/bpf/progs/mptcp_bpf_userspace_pm.c b/tools/testing/selftests/bpf/progs/mptcp_bpf_userspace_pm.c
 new file mode 100644
 index XXXXXXX..XXXXXXX
 --- /dev/null
 +++ b/tools/testing/selftests/bpf/progs/mptcp_bpf_userspace_pm.c
@@ -XXX,XX +XXX,XX @@
 +// SPDX-License-Identifier: GPL-2.0
 +/* Copyright (c) 2025, Kylin Software */
 +
 +#include "mptcp_bpf.h"
 +
 +char _license[] SEC("license") = "GPL";
 +
 +extern bool CONFIG_MPTCP_IPV6 __kconfig __weak;
 +
 +extern void bpf_list_add_tail_rcu(struct list_head *new,
 +                  struct list_head *head) __ksym;
 +extern void bpf_list_del_rcu(struct list_head *entry) __ksym;
 +
 +SEC("struct_ops")
 +void BPF_PROG(mptcp_userspace_pm_init, struct mptcp_sock *msk)
 +{
 +    bpf_printk("BPF userspace PM (%s)",
 +           CONFIG_MPTCP_IPV6 ? "IPv6" : "IPv4");
 +}
 +
 +SEC("struct_ops")
 +void BPF_PROG(mptcp_userspace_pm_release, struct mptcp_sock *msk)
 +{
 +}
 +
 +static struct mptcp_pm_addr_entry *
 +mptcp_userspace_pm_lookup_addr(struct mptcp_sock *msk,
 +                   const struct mptcp_addr_info *addr)
 +{
 +    struct mptcp_pm_addr_entry *entry;
 +
 +    bpf_for_each(mptcp_userspace_pm_addr, entry, (struct sock *)msk) {
 +        if (mptcp_addresses_equal(&entry->addr, addr, false))
 +            return entry;
 +    }
 +    return NULL;
 +}
 +
 +static int mptcp_userspace_pm_append_new_local_addr(struct mptcp_sock *msk,
 +                            struct mptcp_pm_addr_entry *entry,
 +                            bool needs_id)
 +{
 +    struct sock *sk = (struct sock *)msk;
 +    unsigned long id_bitmap[4] = { 0 };
 +    struct mptcp_pm_addr_entry *e;
 +    bool addr_match = false;
 +    bool id_match = false;
 +    int ret = -EINVAL;
 +
 +    bpf_bitmap_zero(id_bitmap, MPTCP_PM_MAX_ADDR_ID + 1);
 +
 +    bpf_spin_lock_bh(&msk->pm.lock);
 +    bpf_for_each(mptcp_userspace_pm_addr, e, sk) {
 +        addr_match = mptcp_addresses_equal(&e->addr, &entry->addr, true);
 +        if (addr_match && entry->addr.id == 0 && needs_id)
 +            entry->addr.id = e->addr.id;
 +        id_match = (e->addr.id == entry->addr.id);
 +        if (addr_match || id_match)
 +            break;
 +        bpf_set_bit(e->addr.id, id_bitmap);
 +    }
 +
 +    if (!addr_match && !id_match) {
 +        /* Memory for the entry is allocated from the
 +         * sock option buffer.
 +         */
 +        e = bpf_sock_kmalloc_entry(sk, sizeof(*e), GFP_ATOMIC);
 +        if (!e) {
 +            ret = -ENOMEM;
 +            goto append_err;
 +        }
 +
 +        mptcp_pm_copy_entry(e, entry);
 +        if (!e->addr.id && needs_id)
 +            e->addr.id = bpf_find_next_zero_bit(id_bitmap,
 +                                MPTCP_PM_MAX_ADDR_ID + 1,
 +                                1);
 +        bpf_list_add_tail_rcu(&e->list, &msk->pm.userspace_pm_local_addr_list);
 +        msk->pm.local_addr_used++;
 +        ret = e->addr.id;
 +    } else if (addr_match && id_match) {
 +        ret = entry->addr.id;
 +    }
 +
 +append_err:
 +    bpf_spin_unlock_bh(&msk->pm.lock);
 +    return ret;
 +}
 +
 +SEC("struct_ops")
 +int BPF_PROG(mptcp_userspace_pm_address_announced, struct mptcp_sock *msk,
 +         struct mptcp_pm_addr_entry *local)
 +{
 +    int err;
 +
 +    err = mptcp_userspace_pm_append_new_local_addr(msk, local, false);
 +    if (err < 0)
 +        return err;
 +
-+    bpf_spin_lock_bh(&msk->pm.lock);
++    spin_lock_bh(&msk->pm.lock);
 +
 +    if (mptcp_pm_alloc_anno_list(msk, &local->addr)) {
 +        msk->pm.add_addr_signaled++;
 +        mptcp_pm_announce_addr(msk, &local->addr, false);
 +        mptcp_pm_nl_addr_send_ack(msk);
 +    }
 +
-+    bpf_spin_unlock_bh(&msk->pm.lock);
++    spin_unlock_bh(&msk->pm.lock);
 +
 +    return 0;
 +}
 +
-+static struct mptcp_pm_addr_entry *
+ int mptcp_pm_nl_announce_doit(struct sk_buff *skb, struct genl_info *info)
-+mptcp_userspace_pm_lookup_addr_by_id(struct mptcp_sock *msk, unsigned int id)
+ {
-+{
+     struct mptcp_pm_addr_entry addr_val;
-+    struct mptcp_pm_addr_entry *entry;
++    struct mptcp_pm_param param;
-+
+     struct mptcp_sock *msk;
-+    bpf_for_each(mptcp_userspace_pm_addr, entry, (struct sock *)msk) {
+     struct nlattr *addr;
-+        if (entry->addr.id == id)
+     int err = -EINVAL;
-+            return entry;
+@@ -XXX,XX +XXX,XX @@ int mptcp_pm_nl_announce_doit(struct sk_buff *skb, struct genl_info *info)
-+    }
+         goto announce_err;
-+    return NULL;
+     }
-+}
-+
+-    err = mptcp_userspace_pm_append_new_local_addr(msk, &addr_val, false);
-+SEC("struct_ops")
+-    if (err < 0) {
-+int BPF_PROG(mptcp_userspace_pm_address_removed, struct mptcp_sock *msk, u8 id)
+-        NL_SET_ERR_MSG_ATTR(info->extack, addr,
-+{
+-                    "did not match address and id");
-+    struct mptcp_pm_addr_entry *entry;
+-        goto announce_err;
-+
+-    }
-+    bpf_spin_lock_bh(&msk->pm.lock);
+-
-+    entry = mptcp_userspace_pm_lookup_addr_by_id(msk, id);
+     lock_sock(sk);
-+    if (!entry) {
+-    spin_lock_bh(&msk->pm.lock);
-+        bpf_spin_unlock_bh(&msk->pm.lock);
+-
-+        return -EINVAL;
+-    if (mptcp_pm_alloc_anno_list(msk, &addr_val.addr)) {
-+    }
+-        msk->pm.add_addr_signaled++;
-+
+-        mptcp_pm_announce_addr(msk, &addr_val.addr, false);
-+    bpf_list_del_rcu(&entry->list);
+-        mptcp_pm_nl_addr_send_ack(msk);
-+    bpf_spin_unlock_bh(&msk->pm.lock);
+-    }
-+
+-
-+    mptcp_pm_remove_addr_entry(msk, entry);
+-    spin_unlock_bh(&msk->pm.lock);
-+
++    mptcp_pm_param_set_contexts(&param, &addr_val, NULL);
-+    bpf_sock_kfree_entry((struct sock *)msk, entry, sizeof(*entry));
++    err = msk->pm.ops && msk->pm.ops->address_announced ?
-+
++          msk->pm.ops->address_announced(msk, &param) :
-+    return 0;
++          mptcp_userspace_pm_address_announced(msk, &param);
-+}
+     release_sock(sk);
 +
 +static int mptcp_userspace_pm_delete_local_addr(struct mptcp_sock *msk,
 +                        struct mptcp_pm_addr_entry *addr)
 +{
 +    struct sock *sk = (struct sock *)msk;
 +    struct mptcp_pm_addr_entry *entry;
 +
 +    entry = mptcp_userspace_pm_lookup_addr(msk, &addr->addr);
 +    if (!entry)
 +        return -EINVAL;
 +
 +    bpf_list_del_rcu(&entry->list);
 +    bpf_sock_kfree_entry(sk, entry, sizeof(*entry));
 +    msk->pm.local_addr_used--;
 +    return 0;
 +}
 +
 +SEC("struct_ops")
 +int BPF_PROG(mptcp_userspace_pm_subflow_established, struct mptcp_sock *msk,
 +         struct mptcp_pm_addr_entry *local, struct mptcp_addr_info *remote)
 +{
 +    struct sock *sk = (struct sock *)msk;
 +    int err;
 +
 +    err = mptcp_userspace_pm_append_new_local_addr(msk, local, false);
 +    if (err < 0)
 +        return err;
 +
 +    err = bpf_mptcp_subflow_connect(sk, local, remote);
 +    bpf_spin_lock_bh(&msk->pm.lock);
 +    if (err)
-+        mptcp_userspace_pm_delete_local_addr(msk, local);
++        NL_SET_ERR_MSG_ATTR(info->extack, addr,
-+    else
++                    "did not match address and id");
-+        msk->pm.subflows++;
-+    bpf_spin_unlock_bh(&msk->pm.lock);
+-    err = 0;
-+
+  announce_err:
-+    return err;
+     sock_put(sk);
-+}
+     return err;
-+
+@@ -XXX,XX +XXX,XX @@ int mptcp_userspace_pm_get_addr(u8 id, struct mptcp_pm_addr_entry *addr,
-+SEC("struct_ops")
+ }
-+int BPF_PROG(mptcp_userspace_pm_subflow_closed, struct mptcp_sock *msk,
-+         struct mptcp_pm_addr_entry *local, struct mptcp_addr_info *remote)
+ static struct mptcp_pm_ops mptcp_userspace_pm = {
-+{
++    .address_announced    = mptcp_userspace_pm_address_announced,
-+    struct sock *ssk, *sk = (struct sock *)msk;
+     .get_local_id        = mptcp_userspace_pm_get_local_id,
-+    struct mptcp_subflow_context *subflow;
+     .get_priority        = mptcp_userspace_pm_get_priority,
-+
+     .type            = MPTCP_PM_TYPE_USERSPACE,
 +    ssk = mptcp_pm_find_ssk(msk, &local->addr, remote);
 +    if (!ssk)
 +        return -ESRCH;
 +
 +    subflow = bpf_mptcp_subflow_ctx(ssk);
 +    if (!subflow)
 +        return -EINVAL;
 +
 +    bpf_spin_lock_bh(&msk->pm.lock);
 +    mptcp_userspace_pm_delete_local_addr(msk, local);
 +    bpf_spin_unlock_bh(&msk->pm.lock);
 +    mptcp_subflow_shutdown(sk, ssk, RCV_SHUTDOWN | SEND_SHUTDOWN);
 +    mptcp_close_ssk(sk, ssk, subflow);
 +    BPF_MPTCP_INC_STATS(bpf_sock_net(sk), MPTCP_MIB_RMSUBFLOW);
 +
 +    return 0;
 +}
 +
 +SEC("struct_ops")
 +int BPF_PROG(mptcp_userspace_pm_get_local_id, struct mptcp_sock *msk,
 +         struct mptcp_pm_addr_entry *skc)
 +{
 +    struct mptcp_pm_addr_entry *entry;
 +
 +    bpf_spin_lock_bh(&msk->pm.lock);
 +    entry = mptcp_userspace_pm_lookup_addr(msk, &skc->addr);
 +    bpf_spin_unlock_bh(&msk->pm.lock);
 +    if (entry)
 +        return entry->addr.id;
 +
 +    return mptcp_userspace_pm_append_new_local_addr(msk, skc, true);
 +}
 +
 +SEC("struct_ops")
 +bool BPF_PROG(mptcp_userspace_pm_get_priority, struct mptcp_sock *msk,
 +          struct mptcp_addr_info *skc)
 +{
 +    struct mptcp_pm_addr_entry *entry;
 +    bool backup;
 +
 +    bpf_spin_lock_bh(&msk->pm.lock);
 +    entry = mptcp_userspace_pm_lookup_addr(msk, skc);
 +    backup = entry && !!(entry->flags & MPTCP_PM_ADDR_FLAG_BACKUP);
 +    bpf_spin_unlock_bh(&msk->pm.lock);
 +
 +    return backup;
 +}
 +
 +SEC("struct_ops")
 +int BPF_PROG(mptcp_userspace_pm_set_priority, struct mptcp_sock *msk,
 +         struct mptcp_pm_addr_entry *local, struct mptcp_addr_info *remote)
 +{
 +    struct mptcp_pm_addr_entry *entry;
 +    u8 bkup = 0;
 +
 +    if (local->flags & MPTCP_PM_ADDR_FLAG_BACKUP)
 +        bkup = 1;
 +
 +    bpf_spin_lock_bh(&msk->pm.lock);
 +    entry = mptcp_userspace_pm_lookup_addr(msk, &local->addr);
 +    if (entry) {
 +        if (bkup)
 +            entry->flags |= MPTCP_PM_ADDR_FLAG_BACKUP;
 +        else
 +            entry->flags &= ~MPTCP_PM_ADDR_FLAG_BACKUP;
 +    }
 +    bpf_spin_unlock_bh(&msk->pm.lock);
 +
 +    return mptcp_pm_nl_mp_prio_send_ack(msk, &local->addr, remote, bkup);
 +}
 +
 +SEC(".struct_ops.link")
 +struct mptcp_pm_ops userspace_pm = {
 +    .address_announced    = (void *)mptcp_userspace_pm_address_announced,
 +    .address_removed    = (void *)mptcp_userspace_pm_address_removed,
 +    .subflow_established    = (void *)mptcp_userspace_pm_subflow_established,
 +    .subflow_closed        = (void *)mptcp_userspace_pm_subflow_closed,
 +    .get_local_id        = (void *)mptcp_userspace_pm_get_local_id,
 +    .get_priority        = (void *)mptcp_userspace_pm_get_priority,
 +    .set_priority        = (void *)mptcp_userspace_pm_set_priority,
 +    .init            = (void *)mptcp_userspace_pm_init,
 +    .release        = (void *)mptcp_userspace_pm_release,
 +    .type            = MPTCP_PM_TYPE_BPF_USERSPACE,
 +};
 --
 .43.0

-[PATCH mptcp-next v1 1/5] bpf: Add mptcp path manager struct_ops
+[PATCH mptcp-next v1 7/9] mptcp: pm: userspace: address_removed interface
 From: Geliang Tang <tanggeliang@kylinos.cn>
-This patch implements a new struct bpf_struct_ops for MPTCP BPF path
+Extract address_removed() interface of the userspace PM from the handler
-manager: bpf_mptcp_pm_ops. Register and unregister the bpf path manager
+of netlink command MPTCP_PM_CMD_REMOVE mptcp_pm_nl_remove_doit(), only
-in .reg and .unreg.
+leave the code for parsing address id and obtaining msk through "info"
 in the handler.
-Add write access for some fields of struct mptcp_addr_info, struct
+This interface is invoked under holding the msk socket lock.
 mptcp_pm_addr_entry and struct mptcp_sock in .btf_struct_access.
 This MPTCP BPF path manager implementation is similar to BPF TCP CC. And
 net/ipv4/bpf_tcp_ca.c is a frame of reference for this patch.
 Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
 ---
- net/mptcp/bpf.c | 276 +++++++++++++++++++++++++++++++++++++++++++++++-
+ net/mptcp/pm_userspace.c | 74 ++++++++++++++++++++--------------------
-file changed, 275 insertions(+), 1 deletion(-)
+file changed, 37 insertions(+), 37 deletions(-)
-diff --git a/net/mptcp/bpf.c b/net/mptcp/bpf.c
+diff --git a/net/mptcp/pm_userspace.c b/net/mptcp/pm_userspace.c
 index XXXXXXX..XXXXXXX 100644
---- a/net/mptcp/bpf.c
+--- a/net/mptcp/pm_userspace.c
-+++ b/net/mptcp/bpf.c
++++ b/net/mptcp/pm_userspace.c
-@@ -XXX,XX +XXX,XX @@
+@@ -XXX,XX +XXX,XX @@ static int mptcp_userspace_pm_remove_id_zero_address(struct mptcp_sock *msk)
- #include "protocol.h"
+ {
+     struct mptcp_rm_list list = { .nr = 0 };
- #ifdef CONFIG_BPF_JIT
+     struct mptcp_subflow_context *subflow;
-+static struct bpf_struct_ops bpf_mptcp_pm_ops;
+-    struct sock *sk = (struct sock *)msk;
-+static u32 mptcp_sock_id,
+     bool has_id_0 = false;
-+       mptcp_entry_id;
+-    int err = -EINVAL;
 -    lock_sock(sk);
      mptcp_for_each_subflow(msk, subflow) {
          if (READ_ONCE(subflow->local_id) == 0) {
              has_id_0 = true;
@@ -XXX,XX +XXX,XX @@ static int mptcp_userspace_pm_remove_id_zero_address(struct mptcp_sock *msk)
          }
      }
      if (!has_id_0)
 -        goto remove_err;
 +        return -EINVAL;
      list.ids[list.nr++] = 0;
@@ -XXX,XX +XXX,XX @@ static int mptcp_userspace_pm_remove_id_zero_address(struct mptcp_sock *msk)
      mptcp_pm_remove_addr(msk, &list);
      spin_unlock_bh(&msk->pm.lock);
 -    err = 0;
 -
 -remove_err:
 -    release_sock(sk);
 -    return err;
 +    return 0;
  }
  void mptcp_pm_remove_addr_entry(struct mptcp_sock *msk,
@@ -XXX,XX +XXX,XX @@ void mptcp_pm_remove_addr_entry(struct mptcp_sock *msk,
      spin_unlock_bh(&msk->pm.lock);
  }
 +static int mptcp_userspace_pm_address_removed(struct mptcp_sock *msk,
 +                          struct mptcp_pm_param *param)
 +{
 +    struct mptcp_pm_addr_entry *entry;
 +    u8 id = param->addr.id;
 +
-+/* MPTCP BPF path manager */
++    if (id == 0)
 +        return mptcp_userspace_pm_remove_id_zero_address(msk);
 +
-+static const struct bpf_func_proto *
++    spin_lock_bh(&msk->pm.lock);
-+bpf_mptcp_pm_get_func_proto(enum bpf_func_id func_id,
++    entry = mptcp_userspace_pm_lookup_addr_by_id(msk, id);
-+                const struct bpf_prog *prog)
++    if (!entry) {
-+{
++        spin_unlock_bh(&msk->pm.lock);
-+    switch (func_id) {
++        return -EINVAL;
 +    case BPF_FUNC_sk_storage_get:
 +        return &bpf_sk_storage_get_proto;
 +    case BPF_FUNC_sk_storage_delete:
 +        return &bpf_sk_storage_delete_proto;
 +    default:
 +        return bpf_base_func_proto(func_id, prog);
 +    }
 +}
 +
 +static int bpf_mptcp_pm_btf_struct_access(struct bpf_verifier_log *log,
 +                      const struct bpf_reg_state *reg,
 +                      int off, int size)
 +{
 +    u32 id = reg->btf_id;
 +    size_t end;
 +
 +    if (id == mptcp_sock_id) {
 +        switch (off) {
 +        case offsetof(struct mptcp_sock, pm.add_addr_signaled):
 +            end = offsetofend(struct mptcp_sock, pm.add_addr_signaled);
 +            break;
 +        case offsetof(struct mptcp_sock, pm.local_addr_used):
 +            end = offsetofend(struct mptcp_sock, pm.local_addr_used);
 +            break;
 +        case offsetof(struct mptcp_sock, pm.subflows):
 +            end = offsetofend(struct mptcp_sock, pm.subflows);
 +            break;
 +        default:
 +            bpf_log(log, "no write support to mptcp_sock at off %d\n",
 +                off);
 +            return -EACCES;
 +        }
 +    } else if (id == mptcp_entry_id) {
 +        switch (off) {
 +        case offsetof(struct mptcp_pm_addr_entry, addr.id):
 +            end = offsetofend(struct mptcp_pm_addr_entry, addr.id);
 +            break;
 +        case offsetof(struct mptcp_pm_addr_entry, addr.family):
 +            end = offsetofend(struct mptcp_pm_addr_entry, addr.family);
 +            break;
 +        case offsetof(struct mptcp_pm_addr_entry, addr.port):
 +            end = offsetofend(struct mptcp_pm_addr_entry, addr.port);
 +            break;
 +#if IS_ENABLED(CONFIG_MPTCP_IPV6)
 +        case offsetof(struct mptcp_pm_addr_entry, addr.addr6.s6_addr32[0]):
 +            end = offsetofend(struct mptcp_pm_addr_entry, addr.addr6.s6_addr32[0]);
 +            break;
 +        case offsetof(struct mptcp_pm_addr_entry, addr.addr6.s6_addr32[1]):
 +            end = offsetofend(struct mptcp_pm_addr_entry, addr.addr6.s6_addr32[1]);
 +            break;
 +        case offsetof(struct mptcp_pm_addr_entry, addr.addr6.s6_addr32[2]):
 +            end = offsetofend(struct mptcp_pm_addr_entry, addr.addr6.s6_addr32[2]);
 +            break;
 +        case offsetof(struct mptcp_pm_addr_entry, addr.addr6.s6_addr32[3]):
 +            end = offsetofend(struct mptcp_pm_addr_entry, addr.addr6.s6_addr32[3]);
 +            break;
 +#else
 +        case offsetof(struct mptcp_pm_addr_entry, addr.addr.s_addr):
 +            end = offsetofend(struct mptcp_pm_addr_entry, addr.addr.s_addr);
 +            break;
 +#endif
 +        case offsetof(struct mptcp_pm_addr_entry, flags):
 +            end = offsetofend(struct mptcp_pm_addr_entry, flags);
 +            break;
 +        case offsetof(struct mptcp_pm_addr_entry, ifindex):
 +            end = offsetofend(struct mptcp_pm_addr_entry, ifindex);
 +            break;
 +        default:
 +            bpf_log(log, "no write support to mptcp_pm_addr_entry at off %d\n",
 +                off);
 +            return -EACCES;
 +        }
 +    } else {
 +        bpf_log(log, "only access to mptcp sock or addr or entry is supported\n");
 +        return -EACCES;
 +    }
 +
-+    if (off + size > end) {
++    list_del_rcu(&entry->list);
-+        bpf_log(log, "access beyond %s at off %u size %u ended at %zu",
++    spin_unlock_bh(&msk->pm.lock);
 +            id == mptcp_sock_id ? "mptcp_sock" :
 +            (id == mptcp_entry_id ? "mptcp_pm_addr_entry" : "mptcp_addr_info"),
 +            off, size, end);
 +        return -EACCES;
 +    }
 +
-+    return NOT_INIT;
++    mptcp_pm_remove_addr_entry(msk, entry);
 +}
 +
-+static const struct bpf_verifier_ops bpf_mptcp_pm_verifier_ops = {
++    sock_kfree_s((struct sock *)msk, entry, sizeof(*entry));
 +    .get_func_proto        = bpf_mptcp_pm_get_func_proto,
 +    .is_valid_access    = bpf_tracing_btf_ctx_access,
 +    .btf_struct_access    = bpf_mptcp_pm_btf_struct_access,
 +};
 +
 +static int bpf_mptcp_pm_reg(void *kdata, struct bpf_link *link)
 +{
 +    return mptcp_pm_register(kdata);
 +}
 +
 +static void bpf_mptcp_pm_unreg(void *kdata, struct bpf_link *link)
 +{
 +    mptcp_pm_unregister(kdata);
 +}
 +
 +static int bpf_mptcp_pm_check_member(const struct btf_type *t,
 +                     const struct btf_member *member,
 +                     const struct bpf_prog *prog)
 +{
 +    return 0;
 +}
 +
 +static int bpf_mptcp_pm_init_member(const struct btf_type *t,
 +                    const struct btf_member *member,
 +                    void *kdata, const void *udata)
 +{
 +    const struct mptcp_pm_ops *upm;
 +    struct mptcp_pm_ops *pm;
 +    u32 moff;
 +
 +    upm = (const struct mptcp_pm_ops *)udata;
 +    pm = (struct mptcp_pm_ops *)kdata;
 +
 +    moff = __btf_member_bit_offset(t, member) / 8;
 +    switch (moff) {
 +    case offsetof(struct mptcp_pm_ops, type):
 +        pm->type = upm->type;
 +        return 1;
 +    }
 +
 +    return 0;
 +}
 +
-+static int bpf_mptcp_pm_init(struct btf *btf)
+ int mptcp_pm_nl_remove_doit(struct sk_buff *skb, struct genl_info *info)
-+{
+ {
-+    s32 type_id;
+-    struct mptcp_pm_addr_entry *match;
-+
++    struct mptcp_addr_info addr;
-+    type_id = btf_find_by_name_kind(btf, "mptcp_sock",
++    struct mptcp_pm_param param;
-+                    BTF_KIND_STRUCT);
+     struct mptcp_sock *msk;
-+    if (type_id < 0)
+     struct nlattr *id;
-+        return -EINVAL;
+     int err = -EINVAL;
-+    mptcp_sock_id = type_id;
+     struct sock *sk;
-+
+-    u8 id_val;
-+    type_id = btf_find_by_name_kind(btf, "mptcp_pm_addr_entry",
-+                    BTF_KIND_STRUCT);
+     if (GENL_REQ_ATTR_CHECK(info, MPTCP_PM_ATTR_LOC_ID))
-+    if (type_id < 0)
+         return err;
-+        return -EINVAL;
-+    mptcp_entry_id = type_id;
+     id = info->attrs[MPTCP_PM_ATTR_LOC_ID];
-+
+-    id_val = nla_get_u8(id);
-+    return 0;
++    addr.id = nla_get_u8(id);
-+}
-+
+     msk = mptcp_userspace_pm_get_sock(info);
-+static int bpf_mptcp_pm_validate(void *kdata)
+     if (!msk)
-+{
+@@ -XXX,XX +XXX,XX @@ int mptcp_pm_nl_remove_doit(struct sk_buff *skb, struct genl_info *info)
-+    return mptcp_pm_validate(kdata);
-+}
+     sk = (struct sock *)msk;
-+
-+static int __bpf_mptcp_pm_address_created(struct mptcp_sock *msk)
+-    if (id_val == 0) {
-+{
+-        err = mptcp_userspace_pm_remove_id_zero_address(msk);
-+    return 0;
+-        goto out;
-+}
+-    }
-+
+-
-+static int __bpf_mptcp_pm_address_established(struct mptcp_sock *msk)
+     lock_sock(sk);
-+{
+-
-+    return 0;
+-    spin_lock_bh(&msk->pm.lock);
-+}
+-    match = mptcp_userspace_pm_lookup_addr_by_id(msk, id_val);
-+
+-    if (!match) {
-+static int __bpf_mptcp_pm_address_closed(struct mptcp_sock *msk)
+-        spin_unlock_bh(&msk->pm.lock);
-+{
+-        release_sock(sk);
-+    return 0;
+-        goto out;
-+}
+-    }
-+
+-
-+static int __bpf_mptcp_pm_address_announced(struct mptcp_sock *msk,
+-    list_del_rcu(&match->list);
-+                        struct mptcp_pm_addr_entry *addr)
+-    spin_unlock_bh(&msk->pm.lock);
-+{
+-
-+    return 0;
+-    mptcp_pm_remove_addr_entry(msk, match);
-+}
+-
-+
++    mptcp_pm_param_set_contexts(&param, NULL, &addr);
-+static int __bpf_mptcp_pm_address_removed(struct mptcp_sock *msk, u8 id)
++    err = msk->pm.ops && msk->pm.ops->address_removed ?
-+{
++          msk->pm.ops->address_removed(msk, &param) :
-+    return 0;
++          mptcp_userspace_pm_address_removed(msk, &param);
-+}
+     release_sock(sk);
-+
+-
-+static int __bpf_mptcp_pm_subflow_established(struct mptcp_sock *msk,
+-    sock_kfree_s(sk, match, sizeof(*match));
-+                          struct mptcp_pm_addr_entry *local,
+-
-+                          struct mptcp_addr_info *remote)
+-    err = 0;
-+{
+-out:
-+    return 0;
+     if (err)
-+}
+         NL_SET_ERR_MSG_ATTR_FMT(info->extack, id,
-+
+                     "address with id %u not found",
-+static int __bpf_mptcp_pm_subflow_closed(struct mptcp_sock *msk,
+-                    id_val);
-+                     struct mptcp_pm_addr_entry *local,
++                    addr.id);
-+                     struct mptcp_addr_info *remote)
-+{
+     sock_put(sk);
-+    return 0;
+     return err;
-+}
+@@ -XXX,XX +XXX,XX @@ int mptcp_userspace_pm_get_addr(u8 id, struct mptcp_pm_addr_entry *addr,
-+
-+static int __bpf_mptcp_pm_get_local_id(struct mptcp_sock *msk,
+ static struct mptcp_pm_ops mptcp_userspace_pm = {
-+                       struct mptcp_pm_addr_entry *skc)
+     .address_announced    = mptcp_userspace_pm_address_announced,
-+{
++    .address_removed    = mptcp_userspace_pm_address_removed,
-+    return 0;
+     .get_local_id        = mptcp_userspace_pm_get_local_id,
-+}
+     .get_priority        = mptcp_userspace_pm_get_priority,
-+
+     .type            = MPTCP_PM_TYPE_USERSPACE,
 +static bool __bpf_mptcp_pm_get_priority(struct mptcp_sock *msk,
 +                    struct mptcp_addr_info *skc)
 +{
 +    return 0;
 +}
 +
 +static int __bpf_mptcp_pm_set_priority(struct mptcp_sock *msk,
 +                       struct mptcp_pm_addr_entry *local,
 +                       struct mptcp_addr_info *remote)
 +{
 +    return 0;
 +}
 +
 +static int __bpf_mptcp_pm_address_listener_created(struct mptcp_sock *msk)
 +{
 +    return 0;
 +}
 +
 +static int __bpf_mptcp_pm_address_listener_closed(struct mptcp_sock *msk)
 +{
 +    return 0;
 +}
 +
 +static void __bpf_mptcp_pm_init(struct mptcp_sock *msk)
 +{
 +}
 +
 +static void __bpf_mptcp_pm_release(struct mptcp_sock *msk)
 +{
 +}
 +
 +static struct mptcp_pm_ops __bpf_mptcp_pm_ops = {
 +    .created        = __bpf_mptcp_pm_address_created,
 +    .established        = __bpf_mptcp_pm_address_established,
 +    .closed            = __bpf_mptcp_pm_address_closed,
 +    .address_announced    = __bpf_mptcp_pm_address_announced,
 +    .address_removed    = __bpf_mptcp_pm_address_removed,
 +    .subflow_established    = __bpf_mptcp_pm_subflow_established,
 +    .subflow_closed        = __bpf_mptcp_pm_subflow_closed,
 +    .get_local_id        = __bpf_mptcp_pm_get_local_id,
 +    .get_priority        = __bpf_mptcp_pm_get_priority,
 +    .set_priority        = __bpf_mptcp_pm_set_priority,
 +    .listener_created    = __bpf_mptcp_pm_address_listener_created,
 +    .listener_closed    = __bpf_mptcp_pm_address_listener_closed,
 +    .init            = __bpf_mptcp_pm_init,
 +    .release        = __bpf_mptcp_pm_release,
 +};
 +
 +static struct bpf_struct_ops bpf_mptcp_pm_ops = {
 +    .verifier_ops    = &bpf_mptcp_pm_verifier_ops,
 +    .reg        = bpf_mptcp_pm_reg,
 +    .unreg        = bpf_mptcp_pm_unreg,
 +    .check_member    = bpf_mptcp_pm_check_member,
 +    .init_member    = bpf_mptcp_pm_init_member,
 +    .init        = bpf_mptcp_pm_init,
 +    .validate    = bpf_mptcp_pm_validate,
 +    .name        = "mptcp_pm_ops",
 +    .cfi_stubs    = &__bpf_mptcp_pm_ops,
 +};
 +
  static struct bpf_struct_ops bpf_mptcp_sched_ops;
  static const struct btf_type *mptcp_sock_type, *mptcp_subflow_type __read_mostly;
 -static u32 mptcp_sock_id, mptcp_subflow_id;
 +static u32 mptcp_subflow_id;
  static const struct bpf_func_proto *
  bpf_mptcp_sched_get_func_proto(enum bpf_func_id func_id,
@@ -XXX,XX +XXX,XX @@ static int __init bpf_mptcp_kfunc_init(void)
      ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_STRUCT_OPS,
                             &bpf_mptcp_sched_kfunc_set);
  #ifdef CONFIG_BPF_JIT
 +    ret = ret ?: register_bpf_struct_ops(&bpf_mptcp_pm_ops, mptcp_pm_ops);
      ret = ret ?: register_bpf_struct_ops(&bpf_mptcp_sched_ops, mptcp_sched_ops);
  #endif
 --
 .43.0

-[PATCH mptcp-next v1 2/5] bpf: Register mptcp struct_ops kfunc set
+[PATCH mptcp-next v1 8/9] mptcp: pm: userspace: subflow_established interface
 From: Geliang Tang <tanggeliang@kylinos.cn>
-This patch exports mptcp path manager helpers into BPF, adds these
+Extract subflow_established() interface of the userspace PM from the
-kfunc names into struct_ops kfunc_set and register this set with
+handler of netlink command MPTCP_PM_CMD_SUBFLOW_CREATE
-BPF_PROG_TYPE_STRUCT_OPS type.
         mptcp_pm_nl_subflow_create_doit(),
 only leave the code for obtaining msk through "info", parsing local address
 entry and parsing remote address info in the handler.
 This interface is invoked under holding the msk socket lock.
 Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
 ---
- net/mptcp/bpf.c | 96 +++++++++++++++++++++++++++++++++++++++++++++++++
+ net/mptcp/pm_userspace.c | 54 +++++++++++++++++++++++++---------------
-file changed, 96 insertions(+)
+file changed, 34 insertions(+), 20 deletions(-)
-diff --git a/net/mptcp/bpf.c b/net/mptcp/bpf.c
+diff --git a/net/mptcp/pm_userspace.c b/net/mptcp/pm_userspace.c
 index XXXXXXX..XXXXXXX 100644
---- a/net/mptcp/bpf.c
+--- a/net/mptcp/pm_userspace.c
-+++ b/net/mptcp/bpf.c
++++ b/net/mptcp/pm_userspace.c
-@@ -XXX,XX +XXX,XX @@
+@@ -XXX,XX +XXX,XX @@ int mptcp_pm_nl_remove_doit(struct sk_buff *skb, struct genl_info *info)
- #include <linux/btf_ids.h>
+     return err;
  #include <net/bpf_sk_storage.h>
  #include "protocol.h"
 +#include "mib.h"
  #ifdef CONFIG_BPF_JIT
  static struct bpf_struct_ops bpf_mptcp_pm_ops;
@@ -XXX,XX +XXX,XX @@ bpf_mptcp_subflow_ctx(const struct sock *sk)
      return NULL;
  }
-+__bpf_kfunc static struct sock *
++static int mptcp_userspace_pm_subflow_established(struct mptcp_sock *msk,
-+bpf_mptcp_subflow_tcp_sock(const struct mptcp_subflow_context *subflow)
++                          struct mptcp_pm_param *param)
 +{
-+    if (!subflow)
++    struct mptcp_pm_addr_entry *entry = &param->entry;
-+        return NULL;
++    struct mptcp_addr_info *remote = &param->addr;
 +    struct sock *sk = (struct sock *)msk;
 +    struct mptcp_pm_local local;
 +    int err;
 +
-+    return mptcp_subflow_tcp_sock(subflow);
++    err = mptcp_userspace_pm_append_new_local_addr(msk, entry, false);
-+}
++    if (err < 0)
-+
++        return err;
  __bpf_kfunc static int
  bpf_iter_mptcp_subflow_new(struct bpf_iter_mptcp_subflow *it,
                 struct mptcp_sock *msk)
@@ -XXX,XX +XXX,XX @@ __bpf_kfunc static bool bpf_ipv4_is_private_10(__be32 addr)
      return ipv4_is_private_10(addr);
  }
 +__bpf_kfunc static void bpf_list_add_tail_rcu(struct list_head *new,
 +                          struct list_head *head)
 +{
 +    list_add_tail_rcu(new, head);
 +}
 +
 +__bpf_kfunc static void bpf_list_del_rcu(struct list_head *entry)
 +{
 +    list_del_rcu(entry);
 +}
 +
 +__bpf_kfunc static struct mptcp_pm_addr_entry *
 +bpf_sock_kmalloc_entry(struct sock *sk, int size, gfp_t priority)
 +{
 +    return sock_kmalloc(sk, size, priority);
 +}
 +
 +__bpf_kfunc static void
 +bpf_sock_kfree_entry(struct sock *sk, struct mptcp_pm_addr_entry *entry,
 +             int size)
 +{
 +    sock_kfree_s(sk, entry, size);
 +}
 +
 +__bpf_kfunc static void bpf_bitmap_zero(unsigned long *dst__ign, unsigned int nbits)
 +{
 +    bitmap_zero(dst__ign, nbits);
 +}
 +
 +__bpf_kfunc static void bpf_set_bit(unsigned long nr, unsigned long *addr__ign)
 +{
 +    __set_bit(nr, addr__ign);
 +}
 +
 +__bpf_kfunc static __u8 bpf_find_next_zero_bit(const unsigned long *addr__ign,
 +                           unsigned long size, unsigned long offset)
 +{
 +    return find_next_zero_bit(addr__ign, size, offset);
 +}
 +
 +__bpf_kfunc static int
 +bpf_mptcp_subflow_connect(struct sock *sk,
 +              const struct mptcp_pm_addr_entry *entry,
 +              const struct mptcp_addr_info *remote)
 +{
 +    struct mptcp_pm_local local;
 +
 +    local.addr = entry->addr;
 +    local.flags = entry->flags;
 +    local.ifindex = entry->ifindex;
 +
-+    return __mptcp_subflow_connect(sk, &local, remote);
++    err = __mptcp_subflow_connect(sk, &local, remote);
 +    spin_lock_bh(&msk->pm.lock);
 +    if (err)
 +        mptcp_userspace_pm_delete_local_addr(msk, entry);
 +    else
 +        msk->pm.subflows++;
 +    spin_unlock_bh(&msk->pm.lock);
 +
 +    return err;
 +}
 +
-+__bpf_kfunc static struct net *bpf_sock_net(const struct sock *sk)
+ int mptcp_pm_nl_subflow_create_doit(struct sk_buff *skb, struct genl_info *info)
 +{
 +    return sock_net(sk);
 +}
 +
 +__bpf_kfunc static void BPF_MPTCP_INC_STATS(struct net *net,
 +                        enum linux_mptcp_mib_field field)
 +{
 +    MPTCP_INC_STATS(net, field);
 +}
 +
  __bpf_kfunc static bool bpf_mptcp_subflow_queues_empty(struct sock *sk)
  {
-     return tcp_rtx_queue_empty(sk);
+     struct mptcp_pm_addr_entry entry = { 0 };
-@@ -XXX,XX +XXX,XX @@ __bpf_kfunc_end_defs();
+     struct mptcp_addr_info addr_r;
+     struct nlattr *raddr, *laddr;
- BTF_KFUNCS_START(bpf_mptcp_common_kfunc_ids)
+-    struct mptcp_pm_local local;
- BTF_ID_FLAGS(func, bpf_mptcp_subflow_ctx, KF_RET_NULL)
++    struct mptcp_pm_param param;
-+BTF_ID_FLAGS(func, bpf_mptcp_subflow_tcp_sock, KF_RET_NULL)
+     struct mptcp_sock *msk;
- BTF_ID_FLAGS(func, bpf_iter_mptcp_subflow_new, KF_ITER_NEW | KF_TRUSTED_ARGS)
+     int err = -EINVAL;
- BTF_ID_FLAGS(func, bpf_iter_mptcp_subflow_next, KF_ITER_NEXT | KF_RET_NULL)
+     struct sock *sk;
- BTF_ID_FLAGS(func, bpf_iter_mptcp_subflow_destroy, KF_ITER_DESTROY)
+@@ -XXX,XX +XXX,XX @@ int mptcp_pm_nl_subflow_create_doit(struct sk_buff *skb, struct genl_info *info)
-@@ -XXX,XX +XXX,XX @@ BTF_ID_FLAGS(func, bpf_iter_mptcp_userspace_pm_addr_destroy, KF_ITER_DESTROY)
+         goto create_err;
- BTF_ID_FLAGS(func, bpf_spin_lock_bh)
+     }
- BTF_ID_FLAGS(func, bpf_spin_unlock_bh)
- BTF_ID_FLAGS(func, bpf_ipv4_is_private_10)
+-    err = mptcp_userspace_pm_append_new_local_addr(msk, &entry, false);
-+BTF_ID_FLAGS(func, bpf_list_add_tail_rcu)
+-    if (err < 0) {
-+BTF_ID_FLAGS(func, bpf_list_del_rcu)
+-        NL_SET_ERR_MSG_ATTR(info->extack, laddr,
-+BTF_ID_FLAGS(func, bpf_sock_kmalloc_entry)
+-                    "did not match address and id");
-+BTF_ID_FLAGS(func, bpf_sock_kfree_entry)
+-        goto create_err;
-+BTF_ID_FLAGS(func, mptcp_pm_alloc_anno_list)
+-    }
-+BTF_ID_FLAGS(func, mptcp_pm_announce_addr)
+-
-+BTF_ID_FLAGS(func, mptcp_pm_nl_addr_send_ack, KF_SLEEPABLE)
+-    local.addr = entry.addr;
-+BTF_ID_FLAGS(func, bpf_bitmap_zero)
+-    local.flags = entry.flags;
-+BTF_ID_FLAGS(func, bpf_set_bit)
+-    local.ifindex = entry.ifindex;
-+BTF_ID_FLAGS(func, bpf_find_next_zero_bit)
+-
-+BTF_ID_FLAGS(func, mptcp_pm_remove_addr)
+     lock_sock(sk);
-+BTF_ID_FLAGS(func, mptcp_pm_remove_addr_entry, KF_SLEEPABLE)
+-    err = __mptcp_subflow_connect(sk, &local, &addr_r);
-+BTF_ID_FLAGS(func, bpf_mptcp_subflow_connect, KF_SLEEPABLE)
++    mptcp_pm_param_set_contexts(&param, &entry, &addr_r);
-+BTF_ID_FLAGS(func, mptcp_subflow_shutdown, KF_SLEEPABLE)
++    err = msk->pm.ops && msk->pm.ops->subflow_established ?
-+BTF_ID_FLAGS(func, mptcp_close_ssk, KF_SLEEPABLE)
++          msk->pm.ops->subflow_established(msk, &param) :
-+BTF_ID_FLAGS(func, bpf_sock_net)
++          mptcp_userspace_pm_subflow_established(msk, &param);
-+BTF_ID_FLAGS(func, BPF_MPTCP_INC_STATS)
+     release_sock(sk);
-+BTF_ID_FLAGS(func, mptcp_pm_nl_mp_prio_send_ack, KF_SLEEPABLE)
- BTF_ID_FLAGS(func, bpf_mptcp_sock_acquire, KF_ACQUIRE | KF_RET_NULL)
+     if (err)
- BTF_ID_FLAGS(func, bpf_mptcp_sock_release, KF_RELEASE)
+         GENL_SET_ERR_MSG_FMT(info, "connect error: %d", err);
- BTF_KFUNCS_END(bpf_mptcp_common_kfunc_ids)
-@@ -XXX,XX +XXX,XX @@ static int __init bpf_mptcp_kfunc_init(void)
+-    spin_lock_bh(&msk->pm.lock);
-     ret = register_btf_fmodret_id_set(&bpf_mptcp_fmodret_set);
+-    if (err)
-     ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_CGROUP_SOCKOPT,
+-        mptcp_userspace_pm_delete_local_addr(msk, &entry);
-                            &bpf_mptcp_common_kfunc_set);
+-    else
-+    ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_STRUCT_OPS,
+-        msk->pm.subflows++;
-+                           &bpf_mptcp_common_kfunc_set);
+-    spin_unlock_bh(&msk->pm.lock);
-     ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_STRUCT_OPS,
+-
-                            &bpf_mptcp_sched_kfunc_set);
+  create_err:
- #ifdef CONFIG_BPF_JIT
+     sock_put(sk);
      return err;
@@ -XXX,XX +XXX,XX @@ int mptcp_userspace_pm_get_addr(u8 id, struct mptcp_pm_addr_entry *addr,
  static struct mptcp_pm_ops mptcp_userspace_pm = {
      .address_announced    = mptcp_userspace_pm_address_announced,
      .address_removed    = mptcp_userspace_pm_address_removed,
 +    .subflow_established    = mptcp_userspace_pm_subflow_established,
      .get_local_id        = mptcp_userspace_pm_get_local_id,
      .get_priority        = mptcp_userspace_pm_get_priority,
      .type            = MPTCP_PM_TYPE_USERSPACE,
 --
 .43.0

-[PATCH mptcp-next v1 4/5] selftests/bpf: Implement mptcp pm helpers in BPF
+[PATCH mptcp-next v1 9/9] mptcp: pm: userspace: subflow_closed interface
 From: Geliang Tang <tanggeliang@kylinos.cn>
-This patch implements MPTCP path manager helpers mptcp_pm_copy_addr(),
+Extract subflow_closed() interface of the userspace PM from the handler of
-mptcp_pm_copy_entry(), ipv6_addr_equal(), mptcp_addresses_equal() and
+netlink command MPTCP_PM_CMD_SUBFLOW_DESTROY
-mptcp_pm_find_ssk() in BPF.
     mptcp_pm_nl_subflow_destroy_doit(),
 only leave the code for obtaining msk through "info", parsing local address
 entry and parsing remote address info in the handler.
 This interface is invoked under holding the msk socket lock.
 Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
 ---
- tools/testing/selftests/bpf/progs/mptcp_bpf.h | 110 ++++++++++++++++++
+ net/mptcp/pm_userspace.c | 45 ++++++++++++++++++++++++++--------------
-file changed, 110 insertions(+)
+file changed, 30 insertions(+), 15 deletions(-)
-diff --git a/tools/testing/selftests/bpf/progs/mptcp_bpf.h b/tools/testing/selftests/bpf/progs/mptcp_bpf.h
+diff --git a/net/mptcp/pm_userspace.c b/net/mptcp/pm_userspace.c
 index XXXXXXX..XXXXXXX 100644
---- a/tools/testing/selftests/bpf/progs/mptcp_bpf.h
+--- a/net/mptcp/pm_userspace.c
-+++ b/tools/testing/selftests/bpf/progs/mptcp_bpf.h
++++ b/net/mptcp/pm_userspace.c
-@@ -XXX,XX +XXX,XX @@
+@@ -XXX,XX +XXX,XX @@ static struct sock *mptcp_nl_find_ssk(struct mptcp_sock *msk,
- #define __MPTCP_BPF_H__
+     return NULL;
+ }
- #include "bpf_experimental.h"
-+#include "bpf_tracing_net.h"
++static int mptcp_userspace_pm_subflow_closed(struct mptcp_sock *msk,
++                         struct mptcp_pm_param *param)
- /* mptcp helpers from include/net/mptcp.h */
++{
- #define MPTCP_SUBFLOWS_MAX 8
++    struct mptcp_pm_addr_entry *local = &param->entry;
-@@ -XXX,XX +XXX,XX @@ static inline int list_is_head(const struct list_head *list,
++    struct mptcp_addr_info *remote = &param->addr;
- #define mptcp_for_each_subflow(__msk, __subflow)            \
++    struct sock *ssk, *sk = (struct sock *)msk;
      list_for_each_entry(__subflow, &((__msk)->conn_list), node)
 +/* errno macros from include/uapi/asm-generic/errno-base.h */
 +#define    ESRCH        3    /* No such process */
 +#define    ENOMEM        12    /* Out of Memory */
 +#define    EINVAL        22    /* Invalid argument */
 +
- static __always_inline struct sock *
++    ssk = mptcp_nl_find_ssk(msk, &local->addr, remote);
- mptcp_subflow_tcp_sock(const struct mptcp_subflow_context *subflow)
++    if (!ssk)
- {
++        return -ESRCH;
@@ -XXX,XX +XXX,XX @@ extern void mptcp_subflow_set_scheduled(struct mptcp_subflow_context *subflow,
  extern struct mptcp_subflow_context *
  bpf_mptcp_subflow_ctx_by_pos(const struct mptcp_sched_data *data, unsigned int pos) __ksym;
 +/* reimplemented BPF helpers */
 +static __always_inline void
 +mptcp_pm_copy_addr(struct mptcp_addr_info *dst,
 +           struct mptcp_addr_info *src)
 +{
 +    dst->id = src->id;
 +    dst->family = src->family;
 +    dst->port = src->port;
 +
-+    if (src->family == AF_INET) {
++    spin_lock_bh(&msk->pm.lock);
-+        dst->addr.s_addr = src->addr.s_addr;
++    mptcp_userspace_pm_delete_local_addr(msk, local);
-+    } else if (src->family == AF_INET6) {
++    spin_unlock_bh(&msk->pm.lock);
-+        dst->addr6.s6_addr32[0] = src->addr6.s6_addr32[0];
++    mptcp_subflow_shutdown(sk, ssk, RCV_SHUTDOWN | SEND_SHUTDOWN);
-+        dst->addr6.s6_addr32[1] = src->addr6.s6_addr32[1];
++    mptcp_close_ssk(sk, ssk, mptcp_subflow_ctx(ssk));
-+        dst->addr6.s6_addr32[2] = src->addr6.s6_addr32[2];
++    MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_RMSUBFLOW);
-+        dst->addr6.s6_addr32[3] = src->addr6.s6_addr32[3];
++
-+    }
++    return 0;
 +}
 +
-+static __always_inline void
+ int mptcp_pm_nl_subflow_destroy_doit(struct sk_buff *skb, struct genl_info *info)
-+mptcp_pm_copy_entry(struct mptcp_pm_addr_entry *dst,
+ {
-+            struct mptcp_pm_addr_entry *src)
+     struct mptcp_pm_addr_entry addr_l;
-+{
+     struct mptcp_addr_info addr_r;
-+    mptcp_pm_copy_addr(&dst->addr, &src->addr);
+     struct nlattr *raddr, *laddr;
-+
++    struct mptcp_pm_param param;
-+    dst->flags = src->flags;
+     struct mptcp_sock *msk;
-+    dst->ifindex = src->ifindex;
+-    struct sock *sk, *ssk;
-+}
+     int err = -EINVAL;
-+
++    struct sock *sk;
-+#define inet_sk(ptr) container_of(ptr, struct inet_sock, sk)
-+
+     if (GENL_REQ_ATTR_CHECK(info, MPTCP_PM_ATTR_ADDR) ||
-+#define ipv6_addr_equal(a, b)    ((a).s6_addr32[0] == (b).s6_addr32[0] &&    \
+         GENL_REQ_ATTR_CHECK(info, MPTCP_PM_ATTR_ADDR_REMOTE))
-+                 (a).s6_addr32[1] == (b).s6_addr32[1] &&    \
+@@ -XXX,XX +XXX,XX @@ int mptcp_pm_nl_subflow_destroy_doit(struct sk_buff *skb, struct genl_info *info
-+                 (a).s6_addr32[2] == (b).s6_addr32[2] &&    \
+     }
-+                 (a).s6_addr32[3] == (b).s6_addr32[3])
-+
+     lock_sock(sk);
-+static __always_inline bool
+-    ssk = mptcp_nl_find_ssk(msk, &addr_l.addr, &addr_r);
-+mptcp_addresses_equal(const struct mptcp_addr_info *a,
+-    if (!ssk) {
-+              const struct mptcp_addr_info *b, bool use_port)
+-        GENL_SET_ERR_MSG(info, "subflow not found");
-+{
+-        err = -ESRCH;
-+    bool addr_equals = false;
+-        goto release_sock;
-+
+-    }
-+    if (a->family == b->family) {
+-
-+        if (a->family == AF_INET)
+-    spin_lock_bh(&msk->pm.lock);
-+            addr_equals = a->addr.s_addr == b->addr.s_addr;
+-    mptcp_userspace_pm_delete_local_addr(msk, &addr_l);
-+        else
+-    spin_unlock_bh(&msk->pm.lock);
-+            addr_equals = ipv6_addr_equal(a->addr6, b->addr6);
+-    mptcp_subflow_shutdown(sk, ssk, RCV_SHUTDOWN | SEND_SHUTDOWN);
-+    }
+-    mptcp_close_ssk(sk, ssk, mptcp_subflow_ctx(ssk));
-+
+-    MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_RMSUBFLOW);
-+    if (!addr_equals)
+-release_sock:
-+        return false;
++    mptcp_pm_param_set_contexts(&param, &addr_l, &addr_r);
-+    if (!use_port)
++    err = msk->pm.ops && msk->pm.ops->subflow_closed ?
-+        return true;
++          msk->pm.ops->subflow_closed(msk, &param) :
-+
++          mptcp_userspace_pm_subflow_closed(msk, &param);
-+    return a->port == b->port;
+     release_sock(sk);
-+}
++    if (err)
-+
++        GENL_SET_ERR_MSG(info, "subflow not found");
-+static __always_inline struct sock *
-+mptcp_pm_find_ssk(struct mptcp_sock *msk,
+ destroy_err:
-+          const struct mptcp_addr_info *local,
+     sock_put(sk);
-+          const struct mptcp_addr_info *remote)
+@@ -XXX,XX +XXX,XX @@ static struct mptcp_pm_ops mptcp_userspace_pm = {
-+{
+     .address_announced    = mptcp_userspace_pm_address_announced,
-+    struct mptcp_subflow_context *subflow;
+     .address_removed    = mptcp_userspace_pm_address_removed,
-+
+     .subflow_established    = mptcp_userspace_pm_subflow_established,
-+    if (local->family != remote->family)
++    .subflow_closed        = mptcp_userspace_pm_subflow_closed,
-+        return NULL;
+     .get_local_id        = mptcp_userspace_pm_get_local_id,
-+
+     .get_priority        = mptcp_userspace_pm_get_priority,
-+    bpf_for_each(mptcp_subflow, subflow, msk) {
+     .type            = MPTCP_PM_TYPE_USERSPACE,
 +        const struct inet_sock *issk;
 +        struct sock *ssk;
 +
 +        ssk = bpf_mptcp_subflow_tcp_sock(subflow);
 +        if (!ssk)
 +            continue;
 +
 +        if (local->family != ssk->sk_family)
 +            continue;
 +
 +        issk = bpf_core_cast(inet_sk(ssk), struct inet_sock);
 +
 +        switch (ssk->sk_family) {
 +        case AF_INET:
 +            if (issk->inet_saddr != local->addr.s_addr ||
 +                issk->inet_daddr != remote->addr.s_addr)
 +                continue;
 +            break;
 +        case AF_INET6: {
 +            if (!ipv6_addr_equal(local->addr6, issk->pinet6->saddr) ||
 +                !ipv6_addr_equal(remote->addr6, ssk->sk_v6_daddr))
 +                continue;
 +            break;
 +        }
 +        default:
 +            continue;
 +        }
 +
 +        if (issk->inet_sport == local->port &&
 +            issk->inet_dport == remote->port)
 +            return ssk;
 +    }
 +
 +    return NULL;
 +}
 +
  #endif
 --
 .43.0

From: Geliang Tang <tanggeliang@kylinos.cn>

This patch implements a new struct bpf_struct_ops for MPTCP BPF path
manager: bpf_mptcp_pm_ops. Register and unregister the bpf path manager
in .reg and .unreg.

Add write access for some fields of struct mptcp_addr_info, struct
mptcp_pm_addr_entry and struct mptcp_sock in .btf_struct_access.

This MPTCP BPF path manager implementation is similar to BPF TCP CC. And
net/ipv4/bpf_tcp_ca.c is a frame of reference for this patch.

Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
---
 net/mptcp/bpf.c | 276 +++++++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 275 insertions(+), 1 deletion(-)

diff --git a/net/mptcp/bpf.c b/net/mptcp/bpf.c
index XXXXXXX..XXXXXXX 100644
--- a/net/mptcp/bpf.c
+++ b/net/mptcp/bpf.c
@@ -XXX,XX +XXX,XX @@
 #include "protocol.h"
 
 #ifdef CONFIG_BPF_JIT
+static struct bpf_struct_ops bpf_mptcp_pm_ops;
+static u32 mptcp_sock_id,
+	   mptcp_entry_id;
+
+/* MPTCP BPF path manager */
+
+static const struct bpf_func_proto *
+bpf_mptcp_pm_get_func_proto(enum bpf_func_id func_id,
+			    const struct bpf_prog *prog)
+{
+	switch (func_id) {
+	case BPF_FUNC_sk_storage_get:
+		return &bpf_sk_storage_get_proto;
+	case BPF_FUNC_sk_storage_delete:
+		return &bpf_sk_storage_delete_proto;
+	default:
+		return bpf_base_func_proto(func_id, prog);
+	}
+}
+
+static int bpf_mptcp_pm_btf_struct_access(struct bpf_verifier_log *log,
+					  const struct bpf_reg_state *reg,
+					  int off, int size)
+{
+	u32 id = reg->btf_id;
+	size_t end;
+
+	if (id == mptcp_sock_id) {
+		switch (off) {
+		case offsetof(struct mptcp_sock, pm.add_addr_signaled):
+			end = offsetofend(struct mptcp_sock, pm.add_addr_signaled);
+			break;
+		case offsetof(struct mptcp_sock, pm.local_addr_used):
+			end = offsetofend(struct mptcp_sock, pm.local_addr_used);
+			break;
+		case offsetof(struct mptcp_sock, pm.subflows):
+			end = offsetofend(struct mptcp_sock, pm.subflows);
+			break;
+		default:
+			bpf_log(log, "no write support to mptcp_sock at off %d\n",
+				off);
+			return -EACCES;
+		}
+	} else if (id == mptcp_entry_id) {
+		switch (off) {
+		case offsetof(struct mptcp_pm_addr_entry, addr.id):
+			end = offsetofend(struct mptcp_pm_addr_entry, addr.id);
+			break;
+		case offsetof(struct mptcp_pm_addr_entry, addr.family):
+			end = offsetofend(struct mptcp_pm_addr_entry, addr.family);
+			break;
+		case offsetof(struct mptcp_pm_addr_entry, addr.port):
+			end = offsetofend(struct mptcp_pm_addr_entry, addr.port);
+			break;
+#if IS_ENABLED(CONFIG_MPTCP_IPV6)
+		case offsetof(struct mptcp_pm_addr_entry, addr.addr6.s6_addr32[0]):
+			end = offsetofend(struct mptcp_pm_addr_entry, addr.addr6.s6_addr32[0]);
+			break;
+		case offsetof(struct mptcp_pm_addr_entry, addr.addr6.s6_addr32[1]):
+			end = offsetofend(struct mptcp_pm_addr_entry, addr.addr6.s6_addr32[1]);
+			break;
+		case offsetof(struct mptcp_pm_addr_entry, addr.addr6.s6_addr32[2]):
+			end = offsetofend(struct mptcp_pm_addr_entry, addr.addr6.s6_addr32[2]);
+			break;
+		case offsetof(struct mptcp_pm_addr_entry, addr.addr6.s6_addr32[3]):
+			end = offsetofend(struct mptcp_pm_addr_entry, addr.addr6.s6_addr32[3]);
+			break;
+#else
+		case offsetof(struct mptcp_pm_addr_entry, addr.addr.s_addr):
+			end = offsetofend(struct mptcp_pm_addr_entry, addr.addr.s_addr);
+			break;
+#endif
+		case offsetof(struct mptcp_pm_addr_entry, flags):
+			end = offsetofend(struct mptcp_pm_addr_entry, flags);
+			break;
+		case offsetof(struct mptcp_pm_addr_entry, ifindex):
+			end = offsetofend(struct mptcp_pm_addr_entry, ifindex);
+			break;
+		default:
+			bpf_log(log, "no write support to mptcp_pm_addr_entry at off %d\n",
+				off);
+			return -EACCES;
+		}
+	} else {
+		bpf_log(log, "only access to mptcp sock or addr or entry is supported\n");
+		return -EACCES;
+	}
+
+	if (off + size > end) {
+		bpf_log(log, "access beyond %s at off %u size %u ended at %zu",
+			id == mptcp_sock_id ? "mptcp_sock" :
+			(id == mptcp_entry_id ? "mptcp_pm_addr_entry" : "mptcp_addr_info"),
+			off, size, end);
+		return -EACCES;
+	}
+
+	return NOT_INIT;
+}
+
+static const struct bpf_verifier_ops bpf_mptcp_pm_verifier_ops = {
+	.get_func_proto		= bpf_mptcp_pm_get_func_proto,
+	.is_valid_access	= bpf_tracing_btf_ctx_access,
+	.btf_struct_access	= bpf_mptcp_pm_btf_struct_access,
+};
+
+static int bpf_mptcp_pm_reg(void *kdata, struct bpf_link *link)
+{
+	return mptcp_pm_register(kdata);
+}
+
+static void bpf_mptcp_pm_unreg(void *kdata, struct bpf_link *link)
+{
+	mptcp_pm_unregister(kdata);
+}
+
+static int bpf_mptcp_pm_check_member(const struct btf_type *t,
+				     const struct btf_member *member,
+				     const struct bpf_prog *prog)
+{
+	return 0;
+}
+
+static int bpf_mptcp_pm_init_member(const struct btf_type *t,
+				    const struct btf_member *member,
+				    void *kdata, const void *udata)
+{
+	const struct mptcp_pm_ops *upm;
+	struct mptcp_pm_ops *pm;
+	u32 moff;
+
+	upm = (const struct mptcp_pm_ops *)udata;
+	pm = (struct mptcp_pm_ops *)kdata;
+
+	moff = __btf_member_bit_offset(t, member) / 8;
+	switch (moff) {
+	case offsetof(struct mptcp_pm_ops, type):
+		pm->type = upm->type;
+		return 1;
+	}
+
+	return 0;
+}
+
+static int bpf_mptcp_pm_init(struct btf *btf)
+{
+	s32 type_id;
+
+	type_id = btf_find_by_name_kind(btf, "mptcp_sock",
+					BTF_KIND_STRUCT);
+	if (type_id < 0)
+		return -EINVAL;
+	mptcp_sock_id = type_id;
+
+	type_id = btf_find_by_name_kind(btf, "mptcp_pm_addr_entry",
+					BTF_KIND_STRUCT);
+	if (type_id < 0)
+		return -EINVAL;
+	mptcp_entry_id = type_id;
+
+	return 0;
+}
+
+static int bpf_mptcp_pm_validate(void *kdata)
+{
+	return mptcp_pm_validate(kdata);
+}
+
+static int __bpf_mptcp_pm_address_created(struct mptcp_sock *msk)
+{
+	return 0;
+}
+
+static int __bpf_mptcp_pm_address_established(struct mptcp_sock *msk)
+{
+	return 0;
+}
+
+static int __bpf_mptcp_pm_address_closed(struct mptcp_sock *msk)
+{
+	return 0;
+}
+
+static int __bpf_mptcp_pm_address_announced(struct mptcp_sock *msk,
+					    struct mptcp_pm_addr_entry *addr)
+{
+	return 0;
+}
+
+static int __bpf_mptcp_pm_address_removed(struct mptcp_sock *msk, u8 id)
+{
+	return 0;
+}
+
+static int __bpf_mptcp_pm_subflow_established(struct mptcp_sock *msk,
+					      struct mptcp_pm_addr_entry *local,
+					      struct mptcp_addr_info *remote)
+{
+	return 0;
+}
+
+static int __bpf_mptcp_pm_subflow_closed(struct mptcp_sock *msk,
+					 struct mptcp_pm_addr_entry *local,
+					 struct mptcp_addr_info *remote)
+{
+	return 0;
+}
+
+static int __bpf_mptcp_pm_get_local_id(struct mptcp_sock *msk,
+				       struct mptcp_pm_addr_entry *skc)
+{
+	return 0;
+}
+
+static bool __bpf_mptcp_pm_get_priority(struct mptcp_sock *msk,
+					struct mptcp_addr_info *skc)
+{
+	return 0;
+}
+
+static int __bpf_mptcp_pm_set_priority(struct mptcp_sock *msk,
+				       struct mptcp_pm_addr_entry *local,
+				       struct mptcp_addr_info *remote)
+{
+	return 0;
+}
+
+static int __bpf_mptcp_pm_address_listener_created(struct mptcp_sock *msk)
+{
+	return 0;
+}
+
+static int __bpf_mptcp_pm_address_listener_closed(struct mptcp_sock *msk)
+{
+	return 0;
+}
+
+static void __bpf_mptcp_pm_init(struct mptcp_sock *msk)
+{
+}
+
+static void __bpf_mptcp_pm_release(struct mptcp_sock *msk)
+{
+}
+
+static struct mptcp_pm_ops __bpf_mptcp_pm_ops = {
+	.created		= __bpf_mptcp_pm_address_created,
+	.established		= __bpf_mptcp_pm_address_established,
+	.closed			= __bpf_mptcp_pm_address_closed,
+	.address_announced	= __bpf_mptcp_pm_address_announced,
+	.address_removed	= __bpf_mptcp_pm_address_removed,
+	.subflow_established	= __bpf_mptcp_pm_subflow_established,
+	.subflow_closed		= __bpf_mptcp_pm_subflow_closed,
+	.get_local_id		= __bpf_mptcp_pm_get_local_id,
+	.get_priority		= __bpf_mptcp_pm_get_priority,
+	.set_priority		= __bpf_mptcp_pm_set_priority,
+	.listener_created	= __bpf_mptcp_pm_address_listener_created,
+	.listener_closed	= __bpf_mptcp_pm_address_listener_closed,
+	.init			= __bpf_mptcp_pm_init,
+	.release		= __bpf_mptcp_pm_release,
+};
+
+static struct bpf_struct_ops bpf_mptcp_pm_ops = {
+	.verifier_ops	= &bpf_mptcp_pm_verifier_ops,
+	.reg		= bpf_mptcp_pm_reg,
+	.unreg		= bpf_mptcp_pm_unreg,
+	.check_member	= bpf_mptcp_pm_check_member,
+	.init_member	= bpf_mptcp_pm_init_member,
+	.init		= bpf_mptcp_pm_init,
+	.validate	= bpf_mptcp_pm_validate,
+	.name		= "mptcp_pm_ops",
+	.cfi_stubs	= &__bpf_mptcp_pm_ops,
+};
+
 static struct bpf_struct_ops bpf_mptcp_sched_ops;
 static const struct btf_type *mptcp_sock_type, *mptcp_subflow_type __read_mostly;
-static u32 mptcp_sock_id, mptcp_subflow_id;
+static u32 mptcp_subflow_id;
 
 static const struct bpf_func_proto *
 bpf_mptcp_sched_get_func_proto(enum bpf_func_id func_id,
@@ -XXX,XX +XXX,XX @@ static int __init bpf_mptcp_kfunc_init(void)
 	ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_STRUCT_OPS,
 					       &bpf_mptcp_sched_kfunc_set);
 #ifdef CONFIG_BPF_JIT
+	ret = ret ?: register_bpf_struct_ops(&bpf_mptcp_pm_ops, mptcp_pm_ops);
 	ret = ret ?: register_bpf_struct_ops(&bpf_mptcp_sched_ops, mptcp_sched_ops);
 #endif
 
-- 
2.43.0

From: Geliang Tang <tanggeliang@kylinos.cn>

This patch exports mptcp path manager helpers into BPF, adds these
kfunc names into struct_ops kfunc_set and register this set with
BPF_PROG_TYPE_STRUCT_OPS type.

Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
---
 net/mptcp/bpf.c | 96 +++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 96 insertions(+)

diff --git a/net/mptcp/bpf.c b/net/mptcp/bpf.c
index XXXXXXX..XXXXXXX 100644
--- a/net/mptcp/bpf.c
+++ b/net/mptcp/bpf.c
@@ -XXX,XX +XXX,XX @@
 #include <linux/btf_ids.h>
 #include <net/bpf_sk_storage.h>
 #include "protocol.h"
+#include "mib.h"
 
 #ifdef CONFIG_BPF_JIT
 static struct bpf_struct_ops bpf_mptcp_pm_ops;
@@ -XXX,XX +XXX,XX @@ bpf_mptcp_subflow_ctx(const struct sock *sk)
 	return NULL;
 }
 
+__bpf_kfunc static struct sock *
+bpf_mptcp_subflow_tcp_sock(const struct mptcp_subflow_context *subflow)
+{
+	if (!subflow)
+		return NULL;
+
+	return mptcp_subflow_tcp_sock(subflow);
+}
+
 __bpf_kfunc static int
 bpf_iter_mptcp_subflow_new(struct bpf_iter_mptcp_subflow *it,
 			   struct mptcp_sock *msk)
@@ -XXX,XX +XXX,XX @@ __bpf_kfunc static bool bpf_ipv4_is_private_10(__be32 addr)
 	return ipv4_is_private_10(addr);
 }
 
+__bpf_kfunc static void bpf_list_add_tail_rcu(struct list_head *new,
+					      struct list_head *head)
+{
+	list_add_tail_rcu(new, head);
+}
+
+__bpf_kfunc static void bpf_list_del_rcu(struct list_head *entry)
+{
+	list_del_rcu(entry);
+}
+
+__bpf_kfunc static struct mptcp_pm_addr_entry *
+bpf_sock_kmalloc_entry(struct sock *sk, int size, gfp_t priority)
+{
+	return sock_kmalloc(sk, size, priority);
+}
+
+__bpf_kfunc static void
+bpf_sock_kfree_entry(struct sock *sk, struct mptcp_pm_addr_entry *entry,
+		     int size)
+{
+	sock_kfree_s(sk, entry, size);
+}
+
+__bpf_kfunc static void bpf_bitmap_zero(unsigned long *dst__ign, unsigned int nbits)
+{
+	bitmap_zero(dst__ign, nbits);
+}
+
+__bpf_kfunc static void bpf_set_bit(unsigned long nr, unsigned long *addr__ign)
+{
+	__set_bit(nr, addr__ign);
+}
+
+__bpf_kfunc static __u8 bpf_find_next_zero_bit(const unsigned long *addr__ign,
+					       unsigned long size, unsigned long offset)
+{
+	return find_next_zero_bit(addr__ign, size, offset);
+}
+
+__bpf_kfunc static int
+bpf_mptcp_subflow_connect(struct sock *sk,
+			  const struct mptcp_pm_addr_entry *entry,
+			  const struct mptcp_addr_info *remote)
+{
+	struct mptcp_pm_local local;
+
+	local.addr = entry->addr;
+	local.flags = entry->flags;
+	local.ifindex = entry->ifindex;
+
+	return __mptcp_subflow_connect(sk, &local, remote);
+}
+
+__bpf_kfunc static struct net *bpf_sock_net(const struct sock *sk)
+{
+	return sock_net(sk);
+}
+
+__bpf_kfunc static void BPF_MPTCP_INC_STATS(struct net *net,
+					    enum linux_mptcp_mib_field field)
+{
+	MPTCP_INC_STATS(net, field);
+}
+
 __bpf_kfunc static bool bpf_mptcp_subflow_queues_empty(struct sock *sk)
 {
 	return tcp_rtx_queue_empty(sk);
@@ -XXX,XX +XXX,XX @@ __bpf_kfunc_end_defs();
 
 BTF_KFUNCS_START(bpf_mptcp_common_kfunc_ids)
 BTF_ID_FLAGS(func, bpf_mptcp_subflow_ctx, KF_RET_NULL)
+BTF_ID_FLAGS(func, bpf_mptcp_subflow_tcp_sock, KF_RET_NULL)
 BTF_ID_FLAGS(func, bpf_iter_mptcp_subflow_new, KF_ITER_NEW | KF_TRUSTED_ARGS)
 BTF_ID_FLAGS(func, bpf_iter_mptcp_subflow_next, KF_ITER_NEXT | KF_RET_NULL)
 BTF_ID_FLAGS(func, bpf_iter_mptcp_subflow_destroy, KF_ITER_DESTROY)
@@ -XXX,XX +XXX,XX @@ BTF_ID_FLAGS(func, bpf_iter_mptcp_userspace_pm_addr_destroy, KF_ITER_DESTROY)
 BTF_ID_FLAGS(func, bpf_spin_lock_bh)
 BTF_ID_FLAGS(func, bpf_spin_unlock_bh)
 BTF_ID_FLAGS(func, bpf_ipv4_is_private_10)
+BTF_ID_FLAGS(func, bpf_list_add_tail_rcu)
+BTF_ID_FLAGS(func, bpf_list_del_rcu)
+BTF_ID_FLAGS(func, bpf_sock_kmalloc_entry)
+BTF_ID_FLAGS(func, bpf_sock_kfree_entry)
+BTF_ID_FLAGS(func, mptcp_pm_alloc_anno_list)
+BTF_ID_FLAGS(func, mptcp_pm_announce_addr)
+BTF_ID_FLAGS(func, mptcp_pm_nl_addr_send_ack, KF_SLEEPABLE)
+BTF_ID_FLAGS(func, bpf_bitmap_zero)
+BTF_ID_FLAGS(func, bpf_set_bit)
+BTF_ID_FLAGS(func, bpf_find_next_zero_bit)
+BTF_ID_FLAGS(func, mptcp_pm_remove_addr)
+BTF_ID_FLAGS(func, mptcp_pm_remove_addr_entry, KF_SLEEPABLE)
+BTF_ID_FLAGS(func, bpf_mptcp_subflow_connect, KF_SLEEPABLE)
+BTF_ID_FLAGS(func, mptcp_subflow_shutdown, KF_SLEEPABLE)
+BTF_ID_FLAGS(func, mptcp_close_ssk, KF_SLEEPABLE)
+BTF_ID_FLAGS(func, bpf_sock_net)
+BTF_ID_FLAGS(func, BPF_MPTCP_INC_STATS)
+BTF_ID_FLAGS(func, mptcp_pm_nl_mp_prio_send_ack, KF_SLEEPABLE)
 BTF_ID_FLAGS(func, bpf_mptcp_sock_acquire, KF_ACQUIRE | KF_RET_NULL)
 BTF_ID_FLAGS(func, bpf_mptcp_sock_release, KF_RELEASE)
 BTF_KFUNCS_END(bpf_mptcp_common_kfunc_ids)
@@ -XXX,XX +XXX,XX @@ static int __init bpf_mptcp_kfunc_init(void)
 	ret = register_btf_fmodret_id_set(&bpf_mptcp_fmodret_set);
 	ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_CGROUP_SOCKOPT,
 					       &bpf_mptcp_common_kfunc_set);
+	ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_STRUCT_OPS,
+					       &bpf_mptcp_common_kfunc_set);
 	ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_STRUCT_OPS,
 					       &bpf_mptcp_sched_kfunc_set);
 #ifdef CONFIG_BPF_JIT
-- 
2.43.0

From: Geliang Tang <tanggeliang@kylinos.cn>

To verify that the behavior of BPF path manager is the same as that of
userspace pm in the kernel, a userspace pm self-test has been added.
BPF path manager in the next commit will also use this test.

Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
---
 .../testing/selftests/bpf/prog_tests/mptcp.c  | 160 ++++++++++++++++++
 1 file changed, 160 insertions(+)

From: Geliang Tang <tanggeliang@kylinos.cn>

This patch implements MPTCP path manager helpers mptcp_pm_copy_addr(),
mptcp_pm_copy_entry(), ipv6_addr_equal(), mptcp_addresses_equal() and
mptcp_pm_find_ssk() in BPF.

Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
---
 tools/testing/selftests/bpf/progs/mptcp_bpf.h | 110 ++++++++++++++++++
 1 file changed, 110 insertions(+)

diff --git a/tools/testing/selftests/bpf/progs/mptcp_bpf.h b/tools/testing/selftests/bpf/progs/mptcp_bpf.h
index XXXXXXX..XXXXXXX 100644
--- a/tools/testing/selftests/bpf/progs/mptcp_bpf.h
+++ b/tools/testing/selftests/bpf/progs/mptcp_bpf.h
@@ -XXX,XX +XXX,XX @@
 #define __MPTCP_BPF_H__
 
 #include "bpf_experimental.h"
+#include "bpf_tracing_net.h"
 
 /* mptcp helpers from include/net/mptcp.h */
 #define MPTCP_SUBFLOWS_MAX 8
@@ -XXX,XX +XXX,XX @@ static inline int list_is_head(const struct list_head *list,
 #define mptcp_for_each_subflow(__msk, __subflow)			\
 	list_for_each_entry(__subflow, &((__msk)->conn_list), node)
 
+/* errno macros from include/uapi/asm-generic/errno-base.h */
+#define	ESRCH		3	/* No such process */
+#define	ENOMEM		12	/* Out of Memory */
+#define	EINVAL		22	/* Invalid argument */
+
 static __always_inline struct sock *
 mptcp_subflow_tcp_sock(const struct mptcp_subflow_context *subflow)
 {
@@ -XXX,XX +XXX,XX @@ extern void mptcp_subflow_set_scheduled(struct mptcp_subflow_context *subflow,
 extern struct mptcp_subflow_context *
 bpf_mptcp_subflow_ctx_by_pos(const struct mptcp_sched_data *data, unsigned int pos) __ksym;
 
+/* reimplemented BPF helpers */
+static __always_inline void
+mptcp_pm_copy_addr(struct mptcp_addr_info *dst,
+		   struct mptcp_addr_info *src)
+{
+	dst->id = src->id;
+	dst->family = src->family;
+	dst->port = src->port;
+
+	if (src->family == AF_INET) {
+		dst->addr.s_addr = src->addr.s_addr;
+	} else if (src->family == AF_INET6) {
+		dst->addr6.s6_addr32[0] = src->addr6.s6_addr32[0];
+		dst->addr6.s6_addr32[1] = src->addr6.s6_addr32[1];
+		dst->addr6.s6_addr32[2] = src->addr6.s6_addr32[2];
+		dst->addr6.s6_addr32[3] = src->addr6.s6_addr32[3];
+	}
+}
+
+static __always_inline void
+mptcp_pm_copy_entry(struct mptcp_pm_addr_entry *dst,
+		    struct mptcp_pm_addr_entry *src)
+{
+	mptcp_pm_copy_addr(&dst->addr, &src->addr);
+
+	dst->flags = src->flags;
+	dst->ifindex = src->ifindex;
+}
+
+#define inet_sk(ptr) container_of(ptr, struct inet_sock, sk)
+
+#define ipv6_addr_equal(a, b)	((a).s6_addr32[0] == (b).s6_addr32[0] &&	\
+				 (a).s6_addr32[1] == (b).s6_addr32[1] &&	\
+				 (a).s6_addr32[2] == (b).s6_addr32[2] &&	\
+				 (a).s6_addr32[3] == (b).s6_addr32[3])
+
+static __always_inline bool
+mptcp_addresses_equal(const struct mptcp_addr_info *a,
+		      const struct mptcp_addr_info *b, bool use_port)
+{
+	bool addr_equals = false;
+
+	if (a->family == b->family) {
+		if (a->family == AF_INET)
+			addr_equals = a->addr.s_addr == b->addr.s_addr;
+		else
+			addr_equals = ipv6_addr_equal(a->addr6, b->addr6);
+	}
+
+	if (!addr_equals)
+		return false;
+	if (!use_port)
+		return true;
+
+	return a->port == b->port;
+}
+
+static __always_inline struct sock *
+mptcp_pm_find_ssk(struct mptcp_sock *msk,
+		  const struct mptcp_addr_info *local,
+		  const struct mptcp_addr_info *remote)
+{
+	struct mptcp_subflow_context *subflow;
+
+	if (local->family != remote->family)
+		return NULL;
+
+	bpf_for_each(mptcp_subflow, subflow, msk) {
+		const struct inet_sock *issk;
+		struct sock *ssk;
+
+		ssk = bpf_mptcp_subflow_tcp_sock(subflow);
+		if (!ssk)
+			continue;
+
+		if (local->family != ssk->sk_family)
+			continue;
+
+		issk = bpf_core_cast(inet_sk(ssk), struct inet_sock);
+
+		switch (ssk->sk_family) {
+		case AF_INET:
+			if (issk->inet_saddr != local->addr.s_addr ||
+			    issk->inet_daddr != remote->addr.s_addr)
+				continue;
+			break;
+		case AF_INET6: {
+			if (!ipv6_addr_equal(local->addr6, issk->pinet6->saddr) ||
+			    !ipv6_addr_equal(remote->addr6, ssk->sk_v6_daddr))
+				continue;
+			break;
+		}
+		default:
+			continue;
+		}
+
+		if (issk->inet_sport == local->port &&
+		    issk->inet_dport == remote->port)
+			return ssk;
+	}
+
+	return NULL;
+}
+
 #endif
-- 
2.43.0

From: Geliang Tang <tanggeliang@kylinos.cn>

This patch adds an mptcp bpf userspace pm example program, implements
address_announce, address_remove, subflow_create, subflow_destroy,
get_local_id, is_backup, and set_flags interfaces using almost the
same logic as the userspace pm in kernel.

Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
---
 .../testing/selftests/bpf/prog_tests/mptcp.c  |  51 ++++
 tools/testing/selftests/bpf/progs/mptcp_bpf.h |  75 +++++
 .../bpf/progs/mptcp_bpf_userspace_pm.c        | 275 ++++++++++++++++++
 3 files changed, 401 insertions(+)
 create mode 100644 tools/testing/selftests/bpf/progs/mptcp_bpf_userspace_pm.c

diff --git a/tools/testing/selftests/bpf/prog_tests/mptcp.c b/tools/testing/selftests/bpf/prog_tests/mptcp.c
index XXXXXXX..XXXXXXX 100644
--- a/tools/testing/selftests/bpf/prog_tests/mptcp.c
+++ b/tools/testing/selftests/bpf/prog_tests/mptcp.c
@@ -XXX,XX +XXX,XX @@
 #include "mptcpify.skel.h"
 #include "mptcp_subflow.skel.h"
 #include "mptcp_bpf_iters.skel.h"
+#include "mptcp_bpf_userspace_pm.skel.h"
 #include "mptcp_bpf_first.skel.h"
 #include "mptcp_bpf_bkup.skel.h"
 #include "mptcp_bpf_rr.skel.h"
@@ -XXX,XX +XXX,XX @@
 enum mptcp_pm_type {
 	MPTCP_PM_TYPE_KERNEL = 0,
 	MPTCP_PM_TYPE_USERSPACE,
+	MPTCP_PM_TYPE_BPF_USERSPACE,
 
 	__MPTCP_PM_TYPE_NR,
 	__MPTCP_PM_TYPE_MAX = __MPTCP_PM_TYPE_NR - 1,
@@ -XXX,XX +XXX,XX @@ static void test_userspace_pm(void)
 	netns_free(netns);
 }
 
+static void test_bpf_path_manager(void)
+{
+	struct mptcp_bpf_userspace_pm *skel;
+	struct netns_obj *netns;
+	int err;
+
+	skel = mptcp_bpf_userspace_pm__open();
+	if (!ASSERT_OK_PTR(skel, "open: userspace_pm"))
+		return;
+
+	err = bpf_program__set_flags(skel->progs.mptcp_userspace_pm_address_announced,
+				     BPF_F_SLEEPABLE);
+	err = err ?: bpf_program__set_flags(skel->progs.mptcp_userspace_pm_address_removed,
+					    BPF_F_SLEEPABLE);
+	err = err ?: bpf_program__set_flags(skel->progs.mptcp_userspace_pm_subflow_established,
+					    BPF_F_SLEEPABLE);
+	err = err ?: bpf_program__set_flags(skel->progs.mptcp_userspace_pm_subflow_closed,
+					    BPF_F_SLEEPABLE);
+	err = err ?: bpf_program__set_flags(skel->progs.mptcp_userspace_pm_set_priority,
+					    BPF_F_SLEEPABLE);
+	if (!ASSERT_OK(err, "set sleepable flags"))
+		goto skel_destroy;
+
+	if (!ASSERT_OK(mptcp_bpf_userspace_pm__load(skel), "load: userspace_pm"))
+		goto skel_destroy;
+
+	err = mptcp_bpf_userspace_pm__attach(skel);
+	if (!ASSERT_OK(err, "attach: userspace_pm"))
+		goto skel_destroy;
+
+	netns = netns_new(NS_TEST, true);
+	if (!ASSERT_OK_PTR(netns, "netns_new"))
+		goto skel_destroy;
+
+	err = userspace_pm_init(MPTCP_PM_TYPE_BPF_USERSPACE);
+	if (!ASSERT_OK(err, "userspace_pm_init: bpf pm"))
+		goto close_netns;
+
+	run_userspace_pm(skel->kconfig->CONFIG_MPTCP_IPV6 ? IPV6 : IPV4);
+
+	userspace_pm_cleanup();
+close_netns:
+	netns_free(netns);
+skel_destroy:
+	mptcp_bpf_userspace_pm__destroy(skel);
+}
+
 static struct netns_obj *sched_init(char *flags, char *sched)
 {
 	struct netns_obj *netns;
@@ -XXX,XX +XXX,XX @@ void test_mptcp(void)
 		test_iters_address();
 	if (test__start_subtest("userspace_pm"))
 		test_userspace_pm();
+	if (test__start_subtest("bpf_path_manager"))
+		test_bpf_path_manager();
 	if (test__start_subtest("default"))
 		test_default();
 	if (test__start_subtest("first"))
diff --git a/tools/testing/selftests/bpf/progs/mptcp_bpf.h b/tools/testing/selftests/bpf/progs/mptcp_bpf.h
index XXXXXXX..XXXXXXX 100644
--- a/tools/testing/selftests/bpf/progs/mptcp_bpf.h
+++ b/tools/testing/selftests/bpf/progs/mptcp_bpf.h
@@ -XXX,XX +XXX,XX @@ static inline int list_is_head(const struct list_head *list,
 #define	ENOMEM		12	/* Out of Memory */
 #define	EINVAL		22	/* Invalid argument */
 
+/* mptcp helpers from include/net/mptcp.h */
+#define U8_MAX		((u8)~0U)
+
+/* max value of mptcp_addr_info.id */
+#define MPTCP_PM_MAX_ADDR_ID		U8_MAX
+
+/* mptcp macros from include/uapi/linux/mptcp.h */
+#define MPTCP_PM_ADDR_FLAG_SIGNAL			(1 << 0)
+#define MPTCP_PM_ADDR_FLAG_SUBFLOW			(1 << 1)
+#define MPTCP_PM_ADDR_FLAG_BACKUP			(1 << 2)
+#define MPTCP_PM_ADDR_FLAG_FULLMESH			(1 << 3)
+#define MPTCP_PM_ADDR_FLAG_IMPLICIT			(1 << 4)
+
+/* address families macros from include/linux/socket.h */
+#define AF_UNSPEC	0
+#define AF_INET		2
+#define AF_INET6	10
+
+/* shutdown macros from include/net/sock.h */
+#define RCV_SHUTDOWN	1
+#define SEND_SHUTDOWN	2
+
+/* GFP macros from include/linux/gfp_types.h */
+#define __AC(X,Y)	(X##Y)
+#define _AC(X,Y)	__AC(X,Y)
+#define _UL(x)		(_AC(x, UL))
+#define UL(x)		(_UL(x))
+#define BIT(nr)		(UL(1) << (nr))
+
+#define ___GFP_HIGH		BIT(___GFP_HIGH_BIT)
+#define __GFP_HIGH		((gfp_t)___GFP_HIGH)
+#define ___GFP_KSWAPD_RECLAIM	BIT(___GFP_KSWAPD_RECLAIM_BIT)
+#define __GFP_KSWAPD_RECLAIM	((gfp_t)___GFP_KSWAPD_RECLAIM) /* kswapd can wake */
+#define GFP_ATOMIC		(__GFP_HIGH|__GFP_KSWAPD_RECLAIM)
+
 static __always_inline struct sock *
 mptcp_subflow_tcp_sock(const struct mptcp_subflow_context *subflow)
 {
@@ -XXX,XX +XXX,XX @@ extern void bpf_spin_unlock_bh(spinlock_t *lock) __ksym;
 
 extern bool bpf_ipv4_is_private_10(__be32 addr) __ksym;
 
+extern struct mptcp_pm_addr_entry *
+bpf_sock_kmalloc_entry(struct sock *sk, int size, gfp_t priority) __ksym;
+extern void
+bpf_sock_kfree_entry(struct sock *sk, struct mptcp_pm_addr_entry *entry,
+		     int size) __ksym;
+
+extern bool mptcp_pm_alloc_anno_list(struct mptcp_sock *msk,
+				     const struct mptcp_addr_info *addr) __ksym;
+extern int mptcp_pm_announce_addr(struct mptcp_sock *msk,
+				  const struct mptcp_addr_info *addr,
+				  bool echo) __ksym;
+extern void mptcp_pm_nl_addr_send_ack(struct mptcp_sock *msk) __ksym;
+
+extern void bpf_bitmap_zero(unsigned long *dst, unsigned int nbits) __ksym;
+extern void bpf_set_bit(unsigned long nr, unsigned long *addr) __ksym;
+extern u8 bpf_find_next_zero_bit(const unsigned long *addr,
+				 unsigned long size, unsigned long offset) __ksym;
+
+extern int mptcp_pm_remove_addr(struct mptcp_sock *msk,
+				const struct mptcp_rm_list *rm_list) __ksym;
+extern void mptcp_pm_remove_addr_entry(struct mptcp_sock *msk,
+				       struct mptcp_pm_addr_entry *entry) __ksym;
+
+extern int bpf_mptcp_subflow_connect(struct sock *sk,
+				     const struct mptcp_pm_addr_entry *entry,
+				     const struct mptcp_addr_info *remote) __ksym;
+
+extern void
+mptcp_subflow_shutdown(struct sock *sk, struct sock *ssk, int how) __ksym;
+extern void mptcp_close_ssk(struct sock *sk, struct sock *ssk,
+			    struct mptcp_subflow_context *subflow) __ksym;
+extern struct net *bpf_sock_net(const struct sock *sk) __ksym;
+extern void BPF_MPTCP_INC_STATS(struct net *net,
+				enum linux_mptcp_mib_field field) __ksym;
+
+extern int mptcp_pm_nl_mp_prio_send_ack(struct mptcp_sock *msk,
+					struct mptcp_addr_info *addr,
+					struct mptcp_addr_info *rem,
+					u8 bkup) __ksym;
+
 extern void mptcp_subflow_set_scheduled(struct mptcp_subflow_context *subflow,
 					bool scheduled) __ksym;
 
diff --git a/tools/testing/selftests/bpf/progs/mptcp_bpf_userspace_pm.c b/tools/testing/selftests/bpf/progs/mptcp_bpf_userspace_pm.c
new file mode 100644
index XXXXXXX..XXXXXXX
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/mptcp_bpf_userspace_pm.c
@@ -XXX,XX +XXX,XX @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2025, Kylin Software */
+
+#include "mptcp_bpf.h"
+
+char _license[] SEC("license") = "GPL";
+
+extern bool CONFIG_MPTCP_IPV6 __kconfig __weak;
+
+extern void bpf_list_add_tail_rcu(struct list_head *new,
+				  struct list_head *head) __ksym;
+extern void bpf_list_del_rcu(struct list_head *entry) __ksym;
+
+SEC("struct_ops")
+void BPF_PROG(mptcp_userspace_pm_init, struct mptcp_sock *msk)
+{
+	bpf_printk("BPF userspace PM (%s)",
+		   CONFIG_MPTCP_IPV6 ? "IPv6" : "IPv4");
+}
+
+SEC("struct_ops")
+void BPF_PROG(mptcp_userspace_pm_release, struct mptcp_sock *msk)
+{
+}
+
+static struct mptcp_pm_addr_entry *
+mptcp_userspace_pm_lookup_addr(struct mptcp_sock *msk,
+			       const struct mptcp_addr_info *addr)
+{
+	struct mptcp_pm_addr_entry *entry;
+
+	bpf_for_each(mptcp_userspace_pm_addr, entry, (struct sock *)msk) {
+		if (mptcp_addresses_equal(&entry->addr, addr, false))
+			return entry;
+	}
+	return NULL;
+}
+
+static int mptcp_userspace_pm_append_new_local_addr(struct mptcp_sock *msk,
+						    struct mptcp_pm_addr_entry *entry,
+						    bool needs_id)
+{
+	struct sock *sk = (struct sock *)msk;
+	unsigned long id_bitmap[4] = { 0 };
+	struct mptcp_pm_addr_entry *e;
+	bool addr_match = false;
+	bool id_match = false;
+	int ret = -EINVAL;
+
+	bpf_bitmap_zero(id_bitmap, MPTCP_PM_MAX_ADDR_ID + 1);
+
+	bpf_spin_lock_bh(&msk->pm.lock);
+	bpf_for_each(mptcp_userspace_pm_addr, e, sk) {
+		addr_match = mptcp_addresses_equal(&e->addr, &entry->addr, true);
+		if (addr_match && entry->addr.id == 0 && needs_id)
+			entry->addr.id = e->addr.id;
+		id_match = (e->addr.id == entry->addr.id);
+		if (addr_match || id_match)
+			break;
+		bpf_set_bit(e->addr.id, id_bitmap);
+	}
+
+	if (!addr_match && !id_match) {
+		/* Memory for the entry is allocated from the
+		 * sock option buffer.
+		 */
+		e = bpf_sock_kmalloc_entry(sk, sizeof(*e), GFP_ATOMIC);
+		if (!e) {
+			ret = -ENOMEM;
+			goto append_err;
+		}
+
+		mptcp_pm_copy_entry(e, entry);
+		if (!e->addr.id && needs_id)
+			e->addr.id = bpf_find_next_zero_bit(id_bitmap,
+							    MPTCP_PM_MAX_ADDR_ID + 1,
+							    1);
+		bpf_list_add_tail_rcu(&e->list, &msk->pm.userspace_pm_local_addr_list);
+		msk->pm.local_addr_used++;
+		ret = e->addr.id;
+	} else if (addr_match && id_match) {
+		ret = entry->addr.id;
+	}
+
+append_err:
+	bpf_spin_unlock_bh(&msk->pm.lock);
+	return ret;
+}
+
+SEC("struct_ops")
+int BPF_PROG(mptcp_userspace_pm_address_announced, struct mptcp_sock *msk,
+	     struct mptcp_pm_addr_entry *local)
+{
+	int err;
+
+	err = mptcp_userspace_pm_append_new_local_addr(msk, local, false);
+	if (err < 0)
+		return err;
+
+	bpf_spin_lock_bh(&msk->pm.lock);
+
+	if (mptcp_pm_alloc_anno_list(msk, &local->addr)) {
+		msk->pm.add_addr_signaled++;
+		mptcp_pm_announce_addr(msk, &local->addr, false);
+		mptcp_pm_nl_addr_send_ack(msk);
+	}
+
+	bpf_spin_unlock_bh(&msk->pm.lock);
+
+	return 0;
+}
+
+static struct mptcp_pm_addr_entry *
+mptcp_userspace_pm_lookup_addr_by_id(struct mptcp_sock *msk, unsigned int id)
+{
+	struct mptcp_pm_addr_entry *entry;
+
+	bpf_for_each(mptcp_userspace_pm_addr, entry, (struct sock *)msk) {
+		if (entry->addr.id == id)
+			return entry;
+	}
+	return NULL;
+}
+
+SEC("struct_ops")
+int BPF_PROG(mptcp_userspace_pm_address_removed, struct mptcp_sock *msk, u8 id)
+{
+	struct mptcp_pm_addr_entry *entry;
+
+	bpf_spin_lock_bh(&msk->pm.lock);
+	entry = mptcp_userspace_pm_lookup_addr_by_id(msk, id);
+	if (!entry) {
+		bpf_spin_unlock_bh(&msk->pm.lock);
+		return -EINVAL;
+	}
+
+	bpf_list_del_rcu(&entry->list);
+	bpf_spin_unlock_bh(&msk->pm.lock);
+
+	mptcp_pm_remove_addr_entry(msk, entry);
+
+	bpf_sock_kfree_entry((struct sock *)msk, entry, sizeof(*entry));
+
+	return 0;
+}
+
+static int mptcp_userspace_pm_delete_local_addr(struct mptcp_sock *msk,
+						struct mptcp_pm_addr_entry *addr)
+{
+	struct sock *sk = (struct sock *)msk;
+	struct mptcp_pm_addr_entry *entry;
+
+	entry = mptcp_userspace_pm_lookup_addr(msk, &addr->addr);
+	if (!entry)
+		return -EINVAL;
+
+	bpf_list_del_rcu(&entry->list);
+	bpf_sock_kfree_entry(sk, entry, sizeof(*entry));
+	msk->pm.local_addr_used--;
+	return 0;
+}
+
+SEC("struct_ops")
+int BPF_PROG(mptcp_userspace_pm_subflow_established, struct mptcp_sock *msk,
+	     struct mptcp_pm_addr_entry *local, struct mptcp_addr_info *remote)
+{
+	struct sock *sk = (struct sock *)msk;
+	int err;
+
+	err = mptcp_userspace_pm_append_new_local_addr(msk, local, false);
+	if (err < 0)
+		return err;
+
+	err = bpf_mptcp_subflow_connect(sk, local, remote);
+	bpf_spin_lock_bh(&msk->pm.lock);
+	if (err)
+		mptcp_userspace_pm_delete_local_addr(msk, local);
+	else
+		msk->pm.subflows++;
+	bpf_spin_unlock_bh(&msk->pm.lock);
+
+	return err;
+}
+
+SEC("struct_ops")
+int BPF_PROG(mptcp_userspace_pm_subflow_closed, struct mptcp_sock *msk,
+	     struct mptcp_pm_addr_entry *local, struct mptcp_addr_info *remote)
+{
+	struct sock *ssk, *sk = (struct sock *)msk;
+	struct mptcp_subflow_context *subflow;
+
+	ssk = mptcp_pm_find_ssk(msk, &local->addr, remote);
+	if (!ssk)
+		return -ESRCH;
+
+	subflow = bpf_mptcp_subflow_ctx(ssk);
+	if (!subflow)
+		return -EINVAL;
+
+	bpf_spin_lock_bh(&msk->pm.lock);
+	mptcp_userspace_pm_delete_local_addr(msk, local);
+	bpf_spin_unlock_bh(&msk->pm.lock);
+	mptcp_subflow_shutdown(sk, ssk, RCV_SHUTDOWN | SEND_SHUTDOWN);
+	mptcp_close_ssk(sk, ssk, subflow);
+	BPF_MPTCP_INC_STATS(bpf_sock_net(sk), MPTCP_MIB_RMSUBFLOW);
+
+	return 0;
+}
+
+SEC("struct_ops")
+int BPF_PROG(mptcp_userspace_pm_get_local_id, struct mptcp_sock *msk,
+	     struct mptcp_pm_addr_entry *skc)
+{
+	struct mptcp_pm_addr_entry *entry;
+
+	bpf_spin_lock_bh(&msk->pm.lock);
+	entry = mptcp_userspace_pm_lookup_addr(msk, &skc->addr);
+	bpf_spin_unlock_bh(&msk->pm.lock);
+	if (entry)
+		return entry->addr.id;
+
+	return mptcp_userspace_pm_append_new_local_addr(msk, skc, true);
+}
+
+SEC("struct_ops")
+bool BPF_PROG(mptcp_userspace_pm_get_priority, struct mptcp_sock *msk,
+	      struct mptcp_addr_info *skc)
+{
+	struct mptcp_pm_addr_entry *entry;
+	bool backup;
+
+	bpf_spin_lock_bh(&msk->pm.lock);
+	entry = mptcp_userspace_pm_lookup_addr(msk, skc);
+	backup = entry && !!(entry->flags & MPTCP_PM_ADDR_FLAG_BACKUP);
+	bpf_spin_unlock_bh(&msk->pm.lock);
+
+	return backup;
+}
+
+SEC("struct_ops")
+int BPF_PROG(mptcp_userspace_pm_set_priority, struct mptcp_sock *msk,
+	     struct mptcp_pm_addr_entry *local, struct mptcp_addr_info *remote)
+{
+	struct mptcp_pm_addr_entry *entry;
+	u8 bkup = 0;
+
+	if (local->flags & MPTCP_PM_ADDR_FLAG_BACKUP)
+		bkup = 1;
+
+	bpf_spin_lock_bh(&msk->pm.lock);
+	entry = mptcp_userspace_pm_lookup_addr(msk, &local->addr);
+	if (entry) {
+		if (bkup)
+			entry->flags |= MPTCP_PM_ADDR_FLAG_BACKUP;
+		else
+			entry->flags &= ~MPTCP_PM_ADDR_FLAG_BACKUP;
+	}
+	bpf_spin_unlock_bh(&msk->pm.lock);
+
+	return mptcp_pm_nl_mp_prio_send_ack(msk, &local->addr, remote, bkup);
+}
+
+SEC(".struct_ops.link")
+struct mptcp_pm_ops userspace_pm = {
+	.address_announced	= (void *)mptcp_userspace_pm_address_announced,
+	.address_removed	= (void *)mptcp_userspace_pm_address_removed,
+	.subflow_established	= (void *)mptcp_userspace_pm_subflow_established,
+	.subflow_closed		= (void *)mptcp_userspace_pm_subflow_closed,
+	.get_local_id		= (void *)mptcp_userspace_pm_get_local_id,
+	.get_priority		= (void *)mptcp_userspace_pm_get_priority,
+	.set_priority		= (void *)mptcp_userspace_pm_set_priority,
+	.init			= (void *)mptcp_userspace_pm_init,
+	.release		= (void *)mptcp_userspace_pm_release,
+	.type			= MPTCP_PM_TYPE_BPF_USERSPACE,
+};
-- 
2.43.0

From: Geliang Tang <tanggeliang@kylinos.cn>

This patch defines the code in the loop of traversing all msks in
mptcp_nl_remove_subflow_and_signal_addr() as two new helpers,
mptcp_pm_nl_address_removed() and mptcp_pm_nl_subflow_closed(),
used for signaling a RM_ADDR and closing a subflow respectively.

Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
---
 net/mptcp/pm_netlink.c | 60 +++++++++++++++++++++++++++---------------
 1 file changed, 39 insertions(+), 21 deletions(-)

diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c
index XXXXXXX..XXXXXXX 100644
--- a/net/mptcp/pm_netlink.c
+++ b/net/mptcp/pm_netlink.c
@@ -XXX,XX +XXX,XX @@ static void __mark_subflow_endp_available(struct mptcp_sock *msk, u8 id)
 		msk->pm.local_addr_used--;
 }
 
+static int mptcp_pm_nl_address_removed(struct mptcp_sock *msk,
+				       const struct mptcp_pm_addr_entry *local)
+{
+	bool remove_subflow;
+
+	remove_subflow = mptcp_lookup_subflow_by_saddr(&msk->conn_list, &local->addr);
+	mptcp_pm_remove_anno_addr(msk, &local->addr, remove_subflow &&
+				  !(local->flags & MPTCP_PM_ADDR_FLAG_IMPLICIT));
+	return 0;
+}
+
+static int mptcp_pm_nl_subflow_closed(struct mptcp_sock *msk,
+				      const struct mptcp_pm_addr_entry *local)
+{
+	struct mptcp_rm_list list = { .nr = 1 };
+	bool remove_subflow;
+
+	list.ids[0] = mptcp_endp_get_local_id(msk, &local->addr);
+	remove_subflow = mptcp_lookup_subflow_by_saddr(&msk->conn_list, &local->addr);
+	if (remove_subflow) {
+		spin_lock_bh(&msk->pm.lock);
+		mptcp_pm_nl_rm_subflow_received(msk, &list);
+		spin_unlock_bh(&msk->pm.lock);
+	}
+
+	if (local->flags & MPTCP_PM_ADDR_FLAG_SUBFLOW) {
+		spin_lock_bh(&msk->pm.lock);
+		__mark_subflow_endp_available(msk, list.ids[0]);
+		spin_unlock_bh(&msk->pm.lock);
+	}
+
+	if (msk->mpc_endpoint_id == local->addr.id)
+		msk->mpc_endpoint_id = 0;
+
+	return 0;
+}
+
 static int mptcp_nl_remove_subflow_and_signal_addr(struct net *net,
 						   const struct mptcp_pm_addr_entry *entry)
 {
 	const struct mptcp_addr_info *addr = &entry->addr;
-	struct mptcp_rm_list list = { .nr = 1 };
 	long s_slot = 0, s_num = 0;
 	struct mptcp_sock *msk;
 
@@ -XXX,XX +XXX,XX @@ static int mptcp_nl_remove_subflow_and_signal_addr(struct net *net,
 
 	while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) {
 		struct sock *sk = (struct sock *)msk;
-		bool remove_subflow;
 
 		if (mptcp_pm_is_userspace(msk))
 			goto next;
 
 		lock_sock(sk);
-		remove_subflow = mptcp_lookup_subflow_by_saddr(&msk->conn_list, addr);
-		mptcp_pm_remove_anno_addr(msk, addr, remove_subflow &&
-					  !(entry->flags & MPTCP_PM_ADDR_FLAG_IMPLICIT));
-
-		list.ids[0] = mptcp_endp_get_local_id(msk, addr);
-		if (remove_subflow) {
-			spin_lock_bh(&msk->pm.lock);
-			mptcp_pm_nl_rm_subflow_received(msk, &list);
-			spin_unlock_bh(&msk->pm.lock);
-		}
-
-		if (entry->flags & MPTCP_PM_ADDR_FLAG_SUBFLOW) {
-			spin_lock_bh(&msk->pm.lock);
-			__mark_subflow_endp_available(msk, list.ids[0]);
-			spin_unlock_bh(&msk->pm.lock);
-		}
-
-		if (msk->mpc_endpoint_id == entry->addr.id)
-			msk->mpc_endpoint_id = 0;
+		mptcp_pm_nl_address_removed(msk, entry);
+		mptcp_pm_nl_subflow_closed(msk, entry);
 		release_sock(sk);
 
 next:
-- 
2.43.0

From: Geliang Tang <tanggeliang@kylinos.cn>

Extract address_announced() interface of the in-kernel netlink PM from
the helper mptcp_nl_add_subflow_or_signal_addr(), only leave the code
for traversing all msk in the helper.

This interface is invoked under holding the msk socket lock.

Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
---
 net/mptcp/pm_netlink.c | 34 +++++++++++++++++++++++++---------
 1 file changed, 25 insertions(+), 9 deletions(-)

diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c
index XXXXXXX..XXXXXXX 100644
--- a/net/mptcp/pm_netlink.c
+++ b/net/mptcp/pm_netlink.c
@@ -XXX,XX +XXX,XX @@ static struct pm_nl_pernet *genl_info_pm_nl(struct genl_info *info)
 	return pm_nl_get_pernet(genl_info_net(info));
 }
 
+static int mptcp_pm_nl_address_announced(struct mptcp_sock *msk,
+					 struct mptcp_pm_param *param)
+{
+	struct mptcp_addr_info *addr = &param->addr;
+	struct mptcp_addr_info mpc_addr;
+
+	/* if the endp linked to the init sf is re-added with a != ID */
+	mptcp_local_address((struct sock_common *)msk, &mpc_addr);
+
+	spin_lock_bh(&msk->pm.lock);
+	if (mptcp_addresses_equal(addr, &mpc_addr, addr->port))
+		msk->mpc_endpoint_id = addr->id;
+
+	mptcp_pm_create_subflow_or_signal_addr(msk);
+	spin_unlock_bh(&msk->pm.lock);
+
+	return 0;
+}
+
 static int mptcp_nl_add_subflow_or_signal_addr(struct net *net,
 					       struct mptcp_addr_info *addr)
 {
@@ -XXX,XX +XXX,XX @@ static int mptcp_nl_add_subflow_or_signal_addr(struct net *net,
 
 	while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) {
 		struct sock *sk = (struct sock *)msk;
-		struct mptcp_addr_info mpc_addr;
+		struct mptcp_pm_param param;
 
 		if (!READ_ONCE(msk->fully_established) ||
 		    mptcp_pm_is_userspace(msk))
 			goto next;
 
-		/* if the endp linked to the init sf is re-added with a != ID */
-		mptcp_local_address((struct sock_common *)msk, &mpc_addr);
-
 		lock_sock(sk);
-		spin_lock_bh(&msk->pm.lock);
-		if (mptcp_addresses_equal(addr, &mpc_addr, addr->port))
-			msk->mpc_endpoint_id = addr->id;
-		mptcp_pm_create_subflow_or_signal_addr(msk);
-		spin_unlock_bh(&msk->pm.lock);
+		mptcp_pm_param_set_contexts(&param, NULL, addr);
+		msk->pm.ops && msk->pm.ops->address_announced ?
+			msk->pm.ops->address_announced(msk, &param) :
+			mptcp_pm_nl_address_announced(msk, &param);
 		release_sock(sk);
 
 next:
@@ -XXX,XX +XXX,XX @@ static struct pernet_operations mptcp_pm_pernet_ops = {
 };
 
 static struct mptcp_pm_ops mptcp_netlink_pm = {
+	.address_announced	= mptcp_pm_nl_address_announced,
 	.get_local_id		= mptcp_pm_nl_get_local_id,
 	.get_priority		= mptcp_pm_nl_get_priority,
 	.type			= MPTCP_PM_TYPE_KERNEL,
-- 
2.43.0

From: Geliang Tang <tanggeliang@kylinos.cn>

Update the 2nd parameter of mptcp_pm_nl_address_removed(), and define it
as the address_removed() interface of the in-kernel netlink PM.

This interface is invoked under holding the msk socket lock.

Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
---
 net/mptcp/pm_netlink.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

From: Geliang Tang <tanggeliang@kylinos.cn>

Update mptcp_pm_nl_subflow_established() to match the parameters and
return value of subflow_established() interface and define it as the
interface of the in-kernel netlink PM.

This interface is invoked under holding the msk socket lock.

Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
---
 net/mptcp/pm_netlink.c | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c
index XXXXXXX..XXXXXXX 100644
--- a/net/mptcp/pm_netlink.c
+++ b/net/mptcp/pm_netlink.c
@@ -XXX,XX +XXX,XX @@ static void mptcp_pm_nl_fully_established(struct mptcp_sock *msk)
 	mptcp_pm_create_subflow_or_signal_addr(msk);
 }
 
-static void mptcp_pm_nl_subflow_established(struct mptcp_sock *msk)
+static int mptcp_pm_nl_subflow_established(struct mptcp_sock *msk,
+					   struct mptcp_pm_param *param)
 {
 	mptcp_pm_create_subflow_or_signal_addr(msk);
+
+	return 0;
 }
 
 /* Fill all the local addresses into the array addrs[],
@@ -XXX,XX +XXX,XX @@ static void mptcp_pm_nl_rm_subflow_received(struct mptcp_sock *msk,
 void mptcp_pm_nl_work(struct mptcp_sock *msk)
 {
 	struct mptcp_pm_data *pm = &msk->pm;
+	struct mptcp_pm_param param;
 
 	msk_owned_by_me(msk);
 
@@ -XXX,XX +XXX,XX @@ void mptcp_pm_nl_work(struct mptcp_sock *msk)
 	}
 	if (pm->status & BIT(MPTCP_PM_SUBFLOW_ESTABLISHED)) {
 		pm->status &= ~BIT(MPTCP_PM_SUBFLOW_ESTABLISHED);
-		mptcp_pm_nl_subflow_established(msk);
+		msk->pm.ops && msk->pm.ops->subflow_established ?
+			msk->pm.ops->subflow_established(msk, &param) :
+			mptcp_pm_nl_subflow_established(msk, &param);
 	}
 
 	spin_unlock_bh(&msk->pm.lock);
@@ -XXX,XX +XXX,XX @@ static struct pernet_operations mptcp_pm_pernet_ops = {
 static struct mptcp_pm_ops mptcp_netlink_pm = {
 	.address_announced	= mptcp_pm_nl_address_announced,
 	.address_removed	= mptcp_pm_nl_address_removed,
+	.subflow_established	= mptcp_pm_nl_subflow_established,
 	.get_local_id		= mptcp_pm_nl_get_local_id,
 	.get_priority		= mptcp_pm_nl_get_priority,
 	.type			= MPTCP_PM_TYPE_KERNEL,
-- 
2.43.0

From: Geliang Tang <tanggeliang@kylinos.cn>

Update the 2nd parameter of mptcp_pm_nl_subflow_closed(), and define it
as the subflow_closed() interface of the in-kernel netlink PM.

This interface is invoked under holding the msk socket lock.

Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
---
 net/mptcp/pm_netlink.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c
index XXXXXXX..XXXXXXX 100644
--- a/net/mptcp/pm_netlink.c
+++ b/net/mptcp/pm_netlink.c
@@ -XXX,XX +XXX,XX @@ static int mptcp_pm_nl_address_removed(struct mptcp_sock *msk,
 }
 
 static int mptcp_pm_nl_subflow_closed(struct mptcp_sock *msk,
-				      const struct mptcp_pm_addr_entry *local)
+				      struct mptcp_pm_param *param)
 {
+	struct mptcp_pm_addr_entry *local = &param->entry;
 	struct mptcp_rm_list list = { .nr = 1 };
 	bool remove_subflow;
 
@@ -XXX,XX +XXX,XX @@ static int mptcp_nl_remove_subflow_and_signal_addr(struct net *net,
 		msk->pm.ops && msk->pm.ops->address_removed ?
 			msk->pm.ops->address_removed(msk, &param) :
 			mptcp_pm_nl_address_removed(msk, &param);
-		mptcp_pm_nl_subflow_closed(msk, entry);
+		msk->pm.ops && msk->pm.ops->subflow_closed ?
+			msk->pm.ops->subflow_closed(msk, &param) :
+			mptcp_pm_nl_subflow_closed(msk, &param);
 		release_sock(sk);
 
 next:
@@ -XXX,XX +XXX,XX @@ static struct mptcp_pm_ops mptcp_netlink_pm = {
 	.address_announced	= mptcp_pm_nl_address_announced,
 	.address_removed	= mptcp_pm_nl_address_removed,
 	.subflow_established	= mptcp_pm_nl_subflow_established,
+	.subflow_closed		= mptcp_pm_nl_subflow_closed,
 	.get_local_id		= mptcp_pm_nl_get_local_id,
 	.get_priority		= mptcp_pm_nl_get_priority,
 	.type			= MPTCP_PM_TYPE_KERNEL,
-- 
2.43.0

From: Geliang Tang <tanggeliang@kylinos.cn>

Extract address_announced() interface of the userspace PM from the handler
of netlink command MPTCP_PM_CMD_ANNOUNCE mptcp_pm_nl_announce_doit(), only
leave the code for obtaining msk through "info" and parsing address entry
in the handler.

This interface is invoked under holding the msk socket lock.

Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
---
 net/mptcp/pm_userspace.c | 49 ++++++++++++++++++++++++++--------------
 1 file changed, 32 insertions(+), 17 deletions(-)

diff --git a/net/mptcp/pm_userspace.c b/net/mptcp/pm_userspace.c
index XXXXXXX..XXXXXXX 100644
--- a/net/mptcp/pm_userspace.c
+++ b/net/mptcp/pm_userspace.c
@@ -XXX,XX +XXX,XX @@ static struct mptcp_sock *mptcp_userspace_pm_get_sock(const struct genl_info *in
 	return msk;
 }
 
+static int mptcp_userspace_pm_address_announced(struct mptcp_sock *msk,
+						struct mptcp_pm_param *param)
+{
+	struct mptcp_pm_addr_entry *local = &param->entry;
+	int err;
+
+	err = mptcp_userspace_pm_append_new_local_addr(msk, local, false);
+	if (err < 0)
+		return err;
+
+	spin_lock_bh(&msk->pm.lock);
+
+	if (mptcp_pm_alloc_anno_list(msk, &local->addr)) {
+		msk->pm.add_addr_signaled++;
+		mptcp_pm_announce_addr(msk, &local->addr, false);
+		mptcp_pm_nl_addr_send_ack(msk);
+	}
+
+	spin_unlock_bh(&msk->pm.lock);
+
+	return 0;
+}
+
 int mptcp_pm_nl_announce_doit(struct sk_buff *skb, struct genl_info *info)
 {
 	struct mptcp_pm_addr_entry addr_val;
+	struct mptcp_pm_param param;
 	struct mptcp_sock *msk;
 	struct nlattr *addr;
 	int err = -EINVAL;
@@ -XXX,XX +XXX,XX @@ int mptcp_pm_nl_announce_doit(struct sk_buff *skb, struct genl_info *info)
 		goto announce_err;
 	}
 
-	err = mptcp_userspace_pm_append_new_local_addr(msk, &addr_val, false);
-	if (err < 0) {
-		NL_SET_ERR_MSG_ATTR(info->extack, addr,
-				    "did not match address and id");
-		goto announce_err;
-	}
-
 	lock_sock(sk);
-	spin_lock_bh(&msk->pm.lock);
-
-	if (mptcp_pm_alloc_anno_list(msk, &addr_val.addr)) {
-		msk->pm.add_addr_signaled++;
-		mptcp_pm_announce_addr(msk, &addr_val.addr, false);
-		mptcp_pm_nl_addr_send_ack(msk);
-	}
-
-	spin_unlock_bh(&msk->pm.lock);
+	mptcp_pm_param_set_contexts(&param, &addr_val, NULL);
+	err = msk->pm.ops && msk->pm.ops->address_announced ?
+	      msk->pm.ops->address_announced(msk, &param) :
+	      mptcp_userspace_pm_address_announced(msk, &param);
 	release_sock(sk);
+	if (err)
+		NL_SET_ERR_MSG_ATTR(info->extack, addr,
+				    "did not match address and id");
 
-	err = 0;
  announce_err:
 	sock_put(sk);
 	return err;
@@ -XXX,XX +XXX,XX @@ int mptcp_userspace_pm_get_addr(u8 id, struct mptcp_pm_addr_entry *addr,
 }
 
 static struct mptcp_pm_ops mptcp_userspace_pm = {
+	.address_announced	= mptcp_userspace_pm_address_announced,
 	.get_local_id		= mptcp_userspace_pm_get_local_id,
 	.get_priority		= mptcp_userspace_pm_get_priority,
 	.type			= MPTCP_PM_TYPE_USERSPACE,
-- 
2.43.0

From: Geliang Tang <tanggeliang@kylinos.cn>

Extract address_removed() interface of the userspace PM from the handler
of netlink command MPTCP_PM_CMD_REMOVE mptcp_pm_nl_remove_doit(), only
leave the code for parsing address id and obtaining msk through "info"
in the handler.

This interface is invoked under holding the msk socket lock.

Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
---
 net/mptcp/pm_userspace.c | 74 ++++++++++++++++++++--------------------
 1 file changed, 37 insertions(+), 37 deletions(-)

diff --git a/net/mptcp/pm_userspace.c b/net/mptcp/pm_userspace.c
index XXXXXXX..XXXXXXX 100644
--- a/net/mptcp/pm_userspace.c
+++ b/net/mptcp/pm_userspace.c
@@ -XXX,XX +XXX,XX @@ static int mptcp_userspace_pm_remove_id_zero_address(struct mptcp_sock *msk)
 {
 	struct mptcp_rm_list list = { .nr = 0 };
 	struct mptcp_subflow_context *subflow;
-	struct sock *sk = (struct sock *)msk;
 	bool has_id_0 = false;
-	int err = -EINVAL;
 
-	lock_sock(sk);
 	mptcp_for_each_subflow(msk, subflow) {
 		if (READ_ONCE(subflow->local_id) == 0) {
 			has_id_0 = true;
@@ -XXX,XX +XXX,XX @@ static int mptcp_userspace_pm_remove_id_zero_address(struct mptcp_sock *msk)
 		}
 	}
 	if (!has_id_0)
-		goto remove_err;
+		return -EINVAL;
 
 	list.ids[list.nr++] = 0;
 
@@ -XXX,XX +XXX,XX @@ static int mptcp_userspace_pm_remove_id_zero_address(struct mptcp_sock *msk)
 	mptcp_pm_remove_addr(msk, &list);
 	spin_unlock_bh(&msk->pm.lock);
 
-	err = 0;
-
-remove_err:
-	release_sock(sk);
-	return err;
+	return 0;
 }
 
 void mptcp_pm_remove_addr_entry(struct mptcp_sock *msk,
@@ -XXX,XX +XXX,XX @@ void mptcp_pm_remove_addr_entry(struct mptcp_sock *msk,
 	spin_unlock_bh(&msk->pm.lock);
 }
 
+static int mptcp_userspace_pm_address_removed(struct mptcp_sock *msk,
+					      struct mptcp_pm_param *param)
+{
+	struct mptcp_pm_addr_entry *entry;
+	u8 id = param->addr.id;
+
+	if (id == 0)
+		return mptcp_userspace_pm_remove_id_zero_address(msk);
+
+	spin_lock_bh(&msk->pm.lock);
+	entry = mptcp_userspace_pm_lookup_addr_by_id(msk, id);
+	if (!entry) {
+		spin_unlock_bh(&msk->pm.lock);
+		return -EINVAL;
+	}
+
+	list_del_rcu(&entry->list);
+	spin_unlock_bh(&msk->pm.lock);
+
+	mptcp_pm_remove_addr_entry(msk, entry);
+
+	sock_kfree_s((struct sock *)msk, entry, sizeof(*entry));
+
+	return 0;
+}
+
 int mptcp_pm_nl_remove_doit(struct sk_buff *skb, struct genl_info *info)
 {
-	struct mptcp_pm_addr_entry *match;
+	struct mptcp_addr_info addr;
+	struct mptcp_pm_param param;
 	struct mptcp_sock *msk;
 	struct nlattr *id;
 	int err = -EINVAL;
 	struct sock *sk;
-	u8 id_val;
 
 	if (GENL_REQ_ATTR_CHECK(info, MPTCP_PM_ATTR_LOC_ID))
 		return err;
 
 	id = info->attrs[MPTCP_PM_ATTR_LOC_ID];
-	id_val = nla_get_u8(id);
+	addr.id = nla_get_u8(id);
 
 	msk = mptcp_userspace_pm_get_sock(info);
 	if (!msk)
@@ -XXX,XX +XXX,XX @@ int mptcp_pm_nl_remove_doit(struct sk_buff *skb, struct genl_info *info)
 
 	sk = (struct sock *)msk;
 
-	if (id_val == 0) {
-		err = mptcp_userspace_pm_remove_id_zero_address(msk);
-		goto out;
-	}
-
 	lock_sock(sk);
-
-	spin_lock_bh(&msk->pm.lock);
-	match = mptcp_userspace_pm_lookup_addr_by_id(msk, id_val);
-	if (!match) {
-		spin_unlock_bh(&msk->pm.lock);
-		release_sock(sk);
-		goto out;
-	}
-
-	list_del_rcu(&match->list);
-	spin_unlock_bh(&msk->pm.lock);
-
-	mptcp_pm_remove_addr_entry(msk, match);
-
+	mptcp_pm_param_set_contexts(&param, NULL, &addr);
+	err = msk->pm.ops && msk->pm.ops->address_removed ?
+	      msk->pm.ops->address_removed(msk, &param) :
+	      mptcp_userspace_pm_address_removed(msk, &param);
 	release_sock(sk);
-
-	sock_kfree_s(sk, match, sizeof(*match));
-
-	err = 0;
-out:
 	if (err)
 		NL_SET_ERR_MSG_ATTR_FMT(info->extack, id,
 					"address with id %u not found",
-					id_val);
+					addr.id);
 
 	sock_put(sk);
 	return err;
@@ -XXX,XX +XXX,XX @@ int mptcp_userspace_pm_get_addr(u8 id, struct mptcp_pm_addr_entry *addr,
 
 static struct mptcp_pm_ops mptcp_userspace_pm = {
 	.address_announced	= mptcp_userspace_pm_address_announced,
+	.address_removed	= mptcp_userspace_pm_address_removed,
 	.get_local_id		= mptcp_userspace_pm_get_local_id,
 	.get_priority		= mptcp_userspace_pm_get_priority,
 	.type			= MPTCP_PM_TYPE_USERSPACE,
-- 
2.43.0

From: Geliang Tang <tanggeliang@kylinos.cn>

Extract subflow_established() interface of the userspace PM from the
handler of netlink command MPTCP_PM_CMD_SUBFLOW_CREATE

mptcp_pm_nl_subflow_create_doit(),

only leave the code for obtaining msk through "info", parsing local address
entry and parsing remote address info in the handler.

This interface is invoked under holding the msk socket lock.

Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
---
 net/mptcp/pm_userspace.c | 54 +++++++++++++++++++++++++---------------
 1 file changed, 34 insertions(+), 20 deletions(-)

diff --git a/net/mptcp/pm_userspace.c b/net/mptcp/pm_userspace.c
index XXXXXXX..XXXXXXX 100644
--- a/net/mptcp/pm_userspace.c
+++ b/net/mptcp/pm_userspace.c
@@ -XXX,XX +XXX,XX @@ int mptcp_pm_nl_remove_doit(struct sk_buff *skb, struct genl_info *info)
 	return err;
 }
 
+static int mptcp_userspace_pm_subflow_established(struct mptcp_sock *msk,
+						  struct mptcp_pm_param *param)
+{
+	struct mptcp_pm_addr_entry *entry = &param->entry;
+	struct mptcp_addr_info *remote = &param->addr;
+	struct sock *sk = (struct sock *)msk;
+	struct mptcp_pm_local local;
+	int err;
+
+	err = mptcp_userspace_pm_append_new_local_addr(msk, entry, false);
+	if (err < 0)
+		return err;
+
+	local.addr = entry->addr;
+	local.flags = entry->flags;
+	local.ifindex = entry->ifindex;
+
+	err = __mptcp_subflow_connect(sk, &local, remote);
+	spin_lock_bh(&msk->pm.lock);
+	if (err)
+		mptcp_userspace_pm_delete_local_addr(msk, entry);
+	else
+		msk->pm.subflows++;
+	spin_unlock_bh(&msk->pm.lock);
+
+	return err;
+}
+
 int mptcp_pm_nl_subflow_create_doit(struct sk_buff *skb, struct genl_info *info)
 {
 	struct mptcp_pm_addr_entry entry = { 0 };
 	struct mptcp_addr_info addr_r;
 	struct nlattr *raddr, *laddr;
-	struct mptcp_pm_local local;
+	struct mptcp_pm_param param;
 	struct mptcp_sock *msk;
 	int err = -EINVAL;
 	struct sock *sk;
@@ -XXX,XX +XXX,XX @@ int mptcp_pm_nl_subflow_create_doit(struct sk_buff *skb, struct genl_info *info)
 		goto create_err;
 	}
 
-	err = mptcp_userspace_pm_append_new_local_addr(msk, &entry, false);
-	if (err < 0) {
-		NL_SET_ERR_MSG_ATTR(info->extack, laddr,
-				    "did not match address and id");
-		goto create_err;
-	}
-
-	local.addr = entry.addr;
-	local.flags = entry.flags;
-	local.ifindex = entry.ifindex;
-
 	lock_sock(sk);
-	err = __mptcp_subflow_connect(sk, &local, &addr_r);
+	mptcp_pm_param_set_contexts(&param, &entry, &addr_r);
+	err = msk->pm.ops && msk->pm.ops->subflow_established ?
+	      msk->pm.ops->subflow_established(msk, &param) :
+	      mptcp_userspace_pm_subflow_established(msk, &param);
 	release_sock(sk);
 
 	if (err)
 		GENL_SET_ERR_MSG_FMT(info, "connect error: %d", err);
 
-	spin_lock_bh(&msk->pm.lock);
-	if (err)
-		mptcp_userspace_pm_delete_local_addr(msk, &entry);
-	else
-		msk->pm.subflows++;
-	spin_unlock_bh(&msk->pm.lock);
-
  create_err:
 	sock_put(sk);
 	return err;
@@ -XXX,XX +XXX,XX @@ int mptcp_userspace_pm_get_addr(u8 id, struct mptcp_pm_addr_entry *addr,
 static struct mptcp_pm_ops mptcp_userspace_pm = {
 	.address_announced	= mptcp_userspace_pm_address_announced,
 	.address_removed	= mptcp_userspace_pm_address_removed,
+	.subflow_established	= mptcp_userspace_pm_subflow_established,
 	.get_local_id		= mptcp_userspace_pm_get_local_id,
 	.get_priority		= mptcp_userspace_pm_get_priority,
 	.type			= MPTCP_PM_TYPE_USERSPACE,
-- 
2.43.0

From: Geliang Tang <tanggeliang@kylinos.cn>

Extract subflow_closed() interface of the userspace PM from the handler of
netlink command MPTCP_PM_CMD_SUBFLOW_DESTROY

mptcp_pm_nl_subflow_destroy_doit(),

only leave the code for obtaining msk through "info", parsing local address
entry and parsing remote address info in the handler.

This interface is invoked under holding the msk socket lock.

Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
---
 net/mptcp/pm_userspace.c | 45 ++++++++++++++++++++++++++--------------
 1 file changed, 30 insertions(+), 15 deletions(-)

diff --git a/net/mptcp/pm_userspace.c b/net/mptcp/pm_userspace.c
index XXXXXXX..XXXXXXX 100644
--- a/net/mptcp/pm_userspace.c
+++ b/net/mptcp/pm_userspace.c
@@ -XXX,XX +XXX,XX @@ static struct sock *mptcp_nl_find_ssk(struct mptcp_sock *msk,
 	return NULL;
 }
 
+static int mptcp_userspace_pm_subflow_closed(struct mptcp_sock *msk,
+					     struct mptcp_pm_param *param)
+{
+	struct mptcp_pm_addr_entry *local = &param->entry;
+	struct mptcp_addr_info *remote = &param->addr;
+	struct sock *ssk, *sk = (struct sock *)msk;
+
+	ssk = mptcp_nl_find_ssk(msk, &local->addr, remote);
+	if (!ssk)
+		return -ESRCH;
+
+	spin_lock_bh(&msk->pm.lock);
+	mptcp_userspace_pm_delete_local_addr(msk, local);
+	spin_unlock_bh(&msk->pm.lock);
+	mptcp_subflow_shutdown(sk, ssk, RCV_SHUTDOWN | SEND_SHUTDOWN);
+	mptcp_close_ssk(sk, ssk, mptcp_subflow_ctx(ssk));
+	MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_RMSUBFLOW);
+
+	return 0;
+}
+
 int mptcp_pm_nl_subflow_destroy_doit(struct sk_buff *skb, struct genl_info *info)
 {
 	struct mptcp_pm_addr_entry addr_l;
 	struct mptcp_addr_info addr_r;
 	struct nlattr *raddr, *laddr;
+	struct mptcp_pm_param param;
 	struct mptcp_sock *msk;
-	struct sock *sk, *ssk;
 	int err = -EINVAL;
+	struct sock *sk;
 
 	if (GENL_REQ_ATTR_CHECK(info, MPTCP_PM_ATTR_ADDR) ||
 	    GENL_REQ_ATTR_CHECK(info, MPTCP_PM_ATTR_ADDR_REMOTE))
@@ -XXX,XX +XXX,XX @@ int mptcp_pm_nl_subflow_destroy_doit(struct sk_buff *skb, struct genl_info *info
 	}
 
 	lock_sock(sk);
-	ssk = mptcp_nl_find_ssk(msk, &addr_l.addr, &addr_r);
-	if (!ssk) {
-		GENL_SET_ERR_MSG(info, "subflow not found");
-		err = -ESRCH;
-		goto release_sock;
-	}
-
-	spin_lock_bh(&msk->pm.lock);
-	mptcp_userspace_pm_delete_local_addr(msk, &addr_l);
-	spin_unlock_bh(&msk->pm.lock);
-	mptcp_subflow_shutdown(sk, ssk, RCV_SHUTDOWN | SEND_SHUTDOWN);
-	mptcp_close_ssk(sk, ssk, mptcp_subflow_ctx(ssk));
-	MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_RMSUBFLOW);
-release_sock:
+	mptcp_pm_param_set_contexts(&param, &addr_l, &addr_r);
+	err = msk->pm.ops && msk->pm.ops->subflow_closed ?
+	      msk->pm.ops->subflow_closed(msk, &param) :
+	      mptcp_userspace_pm_subflow_closed(msk, &param);
 	release_sock(sk);
+	if (err)
+		GENL_SET_ERR_MSG(info, "subflow not found");
 
 destroy_err:
 	sock_put(sk);
@@ -XXX,XX +XXX,XX @@ static struct mptcp_pm_ops mptcp_userspace_pm = {
 	.address_announced	= mptcp_userspace_pm_address_announced,
 	.address_removed	= mptcp_userspace_pm_address_removed,
 	.subflow_established	= mptcp_userspace_pm_subflow_established,
+	.subflow_closed		= mptcp_userspace_pm_subflow_closed,
 	.get_local_id		= mptcp_userspace_pm_get_local_id,
 	.get_priority		= mptcp_userspace_pm_get_priority,
 	.type			= MPTCP_PM_TYPE_USERSPACE,
-- 
2.43.0