kernel/linux.git/net/mptcp/pm_userspace.c, branch v7.0.10

mptcp: pm: rename 'subflows' to 'extra_subflows'

2025-09-27T00:44:04+00:00

A few variables linked to the Path-Managers are confusing, and it would help current and future developers, to clarify them. One of them is 'subflows', which in fact represents the number of extra subflows: all the additional subflows created after the initial one, and not the total number of subflows. While at it, add an additional name for the corresponding variable in MPTCP INFO: mptcpi_extra_subflows. 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 Signed-off-by: Matthieu Baerts (NGI0) Link: https://patch.msgid.link/20250925-net-next-mptcp-c-flag-laminar-v1-5-ad126cc47c6b@kernel.org Signed-off-by: Jakub Kicinski

mptcp: pm: Defer freeing of MPTCP userspace path manager entries

2025-04-23T23:27:58+00:00

When path manager entries are deleted from the local address list, they are first unlinked from the address list using list_del_rcu(). The entries must not be freed until after the RCU grace period, but the existing code immediately frees the entry. Use kfree_rcu_mightsleep() and adjust sk_omem_alloc in open code instead of using the sock_kfree_s() helper. This code path is only called in a netlink handler, so the "might sleep" function is preferable to adding a rarely-used rcu_head member to struct mptcp_pm_addr_entry. Fixes: 88d097316371 ("mptcp: drop free_list for deleting entries") Cc: stable@vger.kernel.org Signed-off-by: Mat Martineau Reviewed-by: Matthieu Baerts (NGI0) Signed-off-by: Matthieu Baerts (NGI0) Link: https://patch.msgid.link/20250421-net-mptcp-pm-defer-freeing-v1-1-e731dc6e86b9@kernel.org Signed-off-by: Jakub Kicinski

mptcp: pm: register in-kernel and userspace PM

2025-03-20T09:14:48+00:00

This patch defines the original in-kernel netlink path manager as a new struct mptcp_pm_ops named "mptcp_pm_kernel", and register it in mptcp_pm_kernel_register(). And define the userspace path manager as a new struct mptcp_pm_ops named "mptcp_pm_userspace", and register it in mptcp_pm_init(). To ensure that there's always a valid path manager available, the default path manager "mptcp_pm_kernel" will be skipped in mptcp_pm_unregister(). Signed-off-by: Geliang Tang Reviewed-by: Matthieu Baerts (NGI0) Signed-off-by: Matthieu Baerts (NGI0) Reviewed-by: Simon Horman Link: https://patch.msgid.link/20250313-net-next-mptcp-pm-ops-intro-v1-7-f4e4a88efc50@kernel.org Signed-off-by: Paolo Abeni

mptcp: pm: avoid calling PM specific code from core

2025-03-10T20:35:49+00:00

When destroying an MPTCP socket, some userspace PM specific code was called from mptcp_destroy_common() in protocol.c. That feels wrong, and it is the only case. Instead, the core now calls mptcp_pm_destroy() from pm.c which is now in charge of cleaning the announced addresses list, and ask the different PMs to do extra cleaning if needed, e.g. the userspace PM, if used, will clean the local addresses list. While at it, the userspace PM specific helper has been prefixed with 'mptcp_userspace_pm_' like the other ones. No behavioural changes intended. Reviewed-by: Geliang Tang Signed-off-by: Matthieu Baerts (NGI0) Link: https://patch.msgid.link/20250307-net-next-mptcp-pm-reorg-v1-9-abef20ada03b@kernel.org Signed-off-by: Jakub Kicinski

mptcp: pm: remove '_nl' from mptcp_pm_nl_mp_prio_send_ack

2025-03-10T20:35:48+00:00

Currently, in-kernel PM specific helpers are prefixed with 'mptcp_pm_nl_'. But here 'mptcp_pm_nl_mp_prio_send_ack()' is not specific to this PM: it is used by both the in-kernel and userspace PMs. To avoid confusions, the '_nl' bit has been removed from the name. No behavioural changes intended. Reviewed-by: Geliang Tang Signed-off-by: Matthieu Baerts (NGI0) Link: https://patch.msgid.link/20250307-net-next-mptcp-pm-reorg-v1-3-abef20ada03b@kernel.org Signed-off-by: Jakub Kicinski

mptcp: pm: remove '_nl' from mptcp_pm_nl_addr_send_ack

2025-03-10T20:35:48+00:00

Currently, in-kernel PM specific helpers are prefixed with 'mptcp_pm_nl_'. But here 'mptcp_pm_nl_addr_send_ack()' is not specific to this PM: it is used by both the in-kernel and userspace PMs. To avoid confusions, the '_nl' bit has been removed from the name. No behavioural changes intended. Reviewed-by: Geliang Tang Signed-off-by: Matthieu Baerts (NGI0) Link: https://patch.msgid.link/20250307-net-next-mptcp-pm-reorg-v1-2-abef20ada03b@kernel.org Signed-off-by: Jakub Kicinski

mptcp: pm: use addr entry for get_local_id

2025-03-10T20:35:48+00:00

The following code in mptcp_userspace_pm_get_local_id() that assigns "skc" to "new_entry" is not allowed in BPF if we use the same code to implement the get_local_id() interface of a BFP path manager: memset(&new_entry, 0, sizeof(struct mptcp_pm_addr_entry)); new_entry.addr = *skc; new_entry.addr.id = 0; new_entry.flags = MPTCP_PM_ADDR_FLAG_IMPLICIT; To solve the issue, this patch moves this assignment to "new_entry" forward to mptcp_pm_get_local_id(), and then passing "new_entry" as a parameter to both mptcp_pm_nl_get_local_id() and mptcp_userspace_pm_get_local_id(). No behavioural changes intended. Signed-off-by: Geliang Tang Reviewed-by: Matthieu Baerts (NGI0) Signed-off-by: Matthieu Baerts (NGI0) Link: https://patch.msgid.link/20250307-net-next-mptcp-pm-reorg-v1-1-abef20ada03b@kernel.org Signed-off-by: Jakub Kicinski

mptcp: use sock_kmemdup for address entry

2025-03-04T01:16:34+00:00

Instead of using sock_kmalloc() to allocate an address entry "e" and then immediately duplicate the input "entry" to it, the newly added sock_kmemdup() helper can be used in mptcp_userspace_pm_append_new_local_addr() to simplify the code. More importantly, the code "*e = *entry;" that assigns "entry" to "e" is not easy to implemented in BPF if we use the same code to implement an append_new_local_addr() helper of a BFP path manager. This patch avoids this type of memory assignment operation. Signed-off-by: Geliang Tang Acked-by: Matthieu Baerts (NGI0) Link: https://patch.msgid.link/3e5a307aed213038a87e44ff93b5793229b16279.1740735165.git.tanggeliang@kylinos.cn Signed-off-by: Jakub Kicinski

mptcp: pm: drop inet6_sk after inet_sk

2025-02-25T02:23:43+00:00

In mptcp_event_add_subflow(), mptcp_event_pm_listener() and mptcp_nl_find_ssk(), 'issk' has already been got through inet_sk(). No need to use inet6_sk() to get 'ipv6_pinfo' again, just use issk->pinet6 instead. This patch also drops these 'ipv6_pinfo' variables. Signed-off-by: Geliang Tang Reviewed-by: Matthieu Baerts (NGI0) Signed-off-by: Matthieu Baerts (NGI0) Link: https://patch.msgid.link/20250221-net-next-mptcp-pm-misc-cleanup-3-v1-6-2b70ab1cee79@kernel.org Signed-off-by: Jakub Kicinski

mptcp: pm: drop match in userspace_pm_append_new_local_addr

2025-02-25T02:23:43+00:00

The variable 'match' in mptcp_userspace_pm_append_new_local_addr() is a redundant one, and this patch drops it. No need to define 'match' as 'struct mptcp_pm_addr_entry *' type. In this function, it's only used to check whether it's NULL. It can be defined as a Boolean one. Also other variables 'addr_match' and 'id_match' make 'match' a redundant one, which can be replaced by directly checking 'addr_match && id_match'. Signed-off-by: Geliang Tang Reviewed-by: Matthieu Baerts (NGI0) Signed-off-by: Matthieu Baerts (NGI0) Link: https://patch.msgid.link/20250221-net-next-mptcp-pm-misc-cleanup-3-v1-5-2b70ab1cee79@kernel.org Signed-off-by: Jakub Kicinski