mptcp: pm: in-kernel: rename 'add_addr_accept_max' to 'limit_add_addr_accepted'

A few variables linked to the in-kernel Path-Manager are confusing, and
it would help current and future developers, to clarify them.

One of them is 'add_addr_accept_max', which in fact represents the limit
of ADD_ADDR that can be accepted:  the limit set via 'ip mptcp limit
add_addr_accepted X' for example. It is not linked to the maximum number
of accepted ADD_ADDR.

While at it, add an additional name for the corresponding variable in
MPTCP INFO: mptcpi_limit_add_addr_accepted. Not to break the current
uAPI, the new name is added as a 'define' pointing to the former name.
This will then also help userspace devs.

No functional changes intended.

Reviewed-by: Geliang Tang <geliang@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20250925-net-next-mptcp-c-flag-laminar-v1-8-ad126cc47c6b@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/include/uapi/linux/mptcp.h b/include/uapi/linux/mptcp.h
index 69fc20db1c2f731d5f93cfee4e58a23119ff7a97..1c275ce96b524cf1525b80967f28b57a59c24a0f 100644 (file)
--- a/include/uapi/linux/mptcp.h
+++ b/include/uapi/linux/mptcp.h
@@ -50,6 +50,7 @@ struct mptcp_info {
        __u8    mptcpi_add_addr_signal_max;
        #define mptcpi_endp_signal_max mptcpi_add_addr_signal_max
        __u8    mptcpi_add_addr_accepted_max;
+       #define mptcpi_limit_add_addr_accepted mptcpi_add_addr_accepted_max
        __u32   mptcpi_flags;
        __u32   mptcpi_token;
        __u64   mptcpi_write_seq;

diff --git a/net/mptcp/pm.c b/net/mptcp/pm.c
index 1100ba8b1ce8243de46b161fb27272c360559bc3..e13bfec50ef8403e7a446f5e008683a718c7176f 100644 (file)
--- a/net/mptcp/pm.c
+++ b/net/mptcp/pm.c
@@ -1039,7 +1039,7 @@ void mptcp_pm_data_reset(struct mptcp_sock *msk)
                            subflows_allowed) ||
                           !!mptcp_pm_get_endp_signal_max(msk));
                WRITE_ONCE(pm->accept_addr,
-                          !!mptcp_pm_get_add_addr_accept_max(msk) &&
+                          !!mptcp_pm_get_limit_add_addr_accepted(msk) &&
                           subflows_allowed);
                WRITE_ONCE(pm->accept_subflow, subflows_allowed);
 

diff --git a/net/mptcp/pm_kernel.c b/net/mptcp/pm_kernel.c
index 740f0b20b941fc457831f3394c187159e9a244e8..92f7419485a82908f55563716b9c6e57f49b716b 100644 (file)
--- a/net/mptcp/pm_kernel.c
+++ b/net/mptcp/pm_kernel.c
@@ -21,7 +21,7 @@ struct pm_nl_pernet {
        unsigned int            addrs;
        unsigned int            stale_loss_cnt;
        unsigned int            endp_signal_max;
-       unsigned int            add_addr_accept_max;
+       unsigned int            limit_add_addr_accepted;
        unsigned int            local_addr_max;
        unsigned int            limit_extra_subflows;
        unsigned int            next_id;
@@ -54,13 +54,13 @@ unsigned int mptcp_pm_get_endp_signal_max(const struct mptcp_sock *msk)
 }
 EXPORT_SYMBOL_GPL(mptcp_pm_get_endp_signal_max);
 
-unsigned int mptcp_pm_get_add_addr_accept_max(const struct mptcp_sock *msk)
+unsigned int mptcp_pm_get_limit_add_addr_accepted(const struct mptcp_sock *msk)
 {
        struct pm_nl_pernet *pernet = pm_nl_get_pernet_from_msk(msk);
 
-       return READ_ONCE(pernet->add_addr_accept_max);
+       return READ_ONCE(pernet->limit_add_addr_accepted);
 }
-EXPORT_SYMBOL_GPL(mptcp_pm_get_add_addr_accept_max);
+EXPORT_SYMBOL_GPL(mptcp_pm_get_limit_add_addr_accepted);
 
 unsigned int mptcp_pm_get_limit_extra_subflows(const struct mptcp_sock *msk)
 {
@@ -547,16 +547,16 @@ static void mptcp_pm_nl_add_addr_received(struct mptcp_sock *msk)
        struct mptcp_pm_local locals[MPTCP_PM_ADDR_MAX];
        struct sock *sk = (struct sock *)msk;
        unsigned int limit_extra_subflows;
-       unsigned int add_addr_accept_max;
+       unsigned int limit_add_addr_accepted;
        struct mptcp_addr_info remote;
        bool sf_created = false;
        int i, nr;
 
-       add_addr_accept_max = mptcp_pm_get_add_addr_accept_max(msk);
+       limit_add_addr_accepted = mptcp_pm_get_limit_add_addr_accepted(msk);
        limit_extra_subflows = mptcp_pm_get_limit_extra_subflows(msk);
 
        pr_debug("accepted %d:%d remote family %d\n",
-                msk->pm.add_addr_accepted, add_addr_accept_max,
+                msk->pm.add_addr_accepted, limit_add_addr_accepted,
                 msk->pm.remote.family);
 
        remote = msk->pm.remote;
@@ -587,7 +587,7 @@ static void mptcp_pm_nl_add_addr_received(struct mptcp_sock *msk)
                /* add_addr_accepted is not decr for ID 0 */
                if (remote.id)
                        msk->pm.add_addr_accepted++;
-               if (msk->pm.add_addr_accepted >= add_addr_accept_max ||
+               if (msk->pm.add_addr_accepted >= limit_add_addr_accepted ||
                    msk->pm.extra_subflows >= limit_extra_subflows)
                        WRITE_ONCE(msk->pm.accept_addr, false);
        }
@@ -596,10 +596,13 @@ static void mptcp_pm_nl_add_addr_received(struct mptcp_sock *msk)
 void mptcp_pm_nl_rm_addr(struct mptcp_sock *msk, u8 rm_id)
 {
        if (rm_id && WARN_ON_ONCE(msk->pm.add_addr_accepted == 0)) {
+               unsigned int limit_add_addr_accepted =
+                       mptcp_pm_get_limit_add_addr_accepted(msk);
+
                /* Note: if the subflow has been closed before, this
                 * add_addr_accepted counter will not be decremented.
                 */
-               if (--msk->pm.add_addr_accepted < mptcp_pm_get_add_addr_accept_max(msk))
+               if (--msk->pm.add_addr_accepted < limit_add_addr_accepted)
                        WRITE_ONCE(msk->pm.accept_addr, true);
        }
 }
@@ -1282,7 +1285,7 @@ int mptcp_pm_nl_set_limits_doit(struct sk_buff *skb, struct genl_info *info)
        int ret;
 
        spin_lock_bh(&pernet->lock);
-       rcv_addrs = pernet->add_addr_accept_max;
+       rcv_addrs = pernet->limit_add_addr_accepted;
        ret = parse_limit(info, MPTCP_PM_ATTR_RCV_ADD_ADDRS, &rcv_addrs);
        if (ret)
                goto unlock;
@@ -1292,7 +1295,7 @@ int mptcp_pm_nl_set_limits_doit(struct sk_buff *skb, struct genl_info *info)
        if (ret)
                goto unlock;
 
-       WRITE_ONCE(pernet->add_addr_accept_max, rcv_addrs);
+       WRITE_ONCE(pernet->limit_add_addr_accepted, rcv_addrs);
        WRITE_ONCE(pernet->limit_extra_subflows, subflows);
 
 unlock:
@@ -1316,7 +1319,7 @@ int mptcp_pm_nl_get_limits_doit(struct sk_buff *skb, struct genl_info *info)
                goto fail;
 
        if (nla_put_u32(msg, MPTCP_PM_ATTR_RCV_ADD_ADDRS,
-                       READ_ONCE(pernet->add_addr_accept_max)))
+                       READ_ONCE(pernet->limit_add_addr_accepted)))
                goto fail;
 
        if (nla_put_u32(msg, MPTCP_PM_ATTR_SUBFLOWS,

diff --git a/net/mptcp/protocol.h b/net/mptcp/protocol.h
index 86c30cd6c1f2ceccba9d14ddac7e6334dd46e21b..114995e1352d02c3e0bcb29ccffcc1ac413be191 100644 (file)
--- a/net/mptcp/protocol.h
+++ b/net/mptcp/protocol.h
@@ -1181,7 +1181,7 @@ void __init mptcp_pm_nl_init(void);
 void mptcp_pm_worker(struct mptcp_sock *msk);
 void __mptcp_pm_kernel_worker(struct mptcp_sock *msk);
 unsigned int mptcp_pm_get_endp_signal_max(const struct mptcp_sock *msk);
-unsigned int mptcp_pm_get_add_addr_accept_max(const struct mptcp_sock *msk);
+unsigned int mptcp_pm_get_limit_add_addr_accepted(const struct mptcp_sock *msk);
 unsigned int mptcp_pm_get_limit_extra_subflows(const struct mptcp_sock *msk);
 unsigned int mptcp_pm_get_local_addr_max(const struct mptcp_sock *msk);
 
@@ -1203,7 +1203,7 @@ static inline bool mptcp_pm_add_addr_c_flag_case(struct mptcp_sock *msk)
 {
        return READ_ONCE(msk->pm.remote_deny_join_id0) &&
               msk->pm.local_addr_used == 0 &&
-              mptcp_pm_get_add_addr_accept_max(msk) == 0 &&
+              mptcp_pm_get_limit_add_addr_accepted(msk) == 0 &&
               msk->pm.extra_subflows < mptcp_pm_get_limit_extra_subflows(msk);
 }
 

diff --git a/net/mptcp/sockopt.c b/net/mptcp/sockopt.c
index 4688e0f25d15d9363b33bdcf3ad75c8295a810e3..5ab9909dbe799bed5c59d2b1b04cc0e88e960574 100644 (file)
--- a/net/mptcp/sockopt.c
+++ b/net/mptcp/sockopt.c
@@ -976,8 +976,8 @@ void mptcp_diag_fill_info(struct mptcp_sock *msk, struct mptcp_info *info)
                        mptcp_pm_get_limit_extra_subflows(msk);
                info->mptcpi_endp_signal_max =
                        mptcp_pm_get_endp_signal_max(msk);
-               info->mptcpi_add_addr_accepted_max =
-                       mptcp_pm_get_add_addr_accept_max(msk);
+               info->mptcpi_limit_add_addr_accepted =
+                       mptcp_pm_get_limit_add_addr_accepted(msk);
                info->mptcpi_local_addr_max =
                        mptcp_pm_get_local_addr_max(msk);
        }