From patchwork Wed Jan 8 08:38:10 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Geliang Tang X-Patchwork-Id: 13930288 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 0F2621A76BC for ; Wed, 8 Jan 2025 08:38:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736325509; cv=none; b=ANA38TLhZZJU08m+MOVRHLo/534p009sVMdfVTbQm6+653WDCfCJiKuEMayrk4oRSJ+Bh46m3I49SCPdspui7vG7sc89zW65dLEDX1WFOzmuSIHFd0GQ2GoD9bZWsMjtEhLuAzmgf9YU77dgIaQOgAsTzjqwPbqKzYqSC+Sew4g= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736325509; c=relaxed/simple; bh=ToG1MF7uW2QUuMDYIFMQfrYfVuMV41rdERJmIk7VGKQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=o72qx0TNEX9VZQnYD0Idq3EkW6P9sXtMcin0vbZpgEYi7Knq5MkJq/dx8t/KAjLz4DQv/o63M1f8lNTn/gPe0stxIlvhJPpv8imbB9X0FgLE//bDJ9u+WO6/Qe+o0Ls4Sza4SnbdFwk6LyW3B7RsiI/wokRdW5zeO7cyzIOjbso= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=dHCB9fgv; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="dHCB9fgv" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6309CC4CEE1; Wed, 8 Jan 2025 08:38:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1736325508; bh=ToG1MF7uW2QUuMDYIFMQfrYfVuMV41rdERJmIk7VGKQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=dHCB9fgvdvDFLXhJ+4vxhQdM+Z+At9VG2OYH34roVdGqqxYPgwJ8YqYEfhNvqe2RP r4SmS6ugedSLhPC3h72jpYZwIeRTe227zreWl5v/UR1+KOGsAP/OoPOfNPq2v32iJe WeLIIzZB2EVgwKGyZ+/TefhXSlVTH1/Ia6DJtA4iSDSW/S7rsT8AuEI1CgNtEPXb04 9wtb2PXfGAYvlO/fNTmuwV6M791phv2szPJ25/d1F5UXkCAhA3a6nx/PbCZ69EHB+f 8RH6So+oQ1rbG5qMDSI5mjBg40+0sMEQE6cQED6mY9HZZkjTMwO6g6yx6yjxkF+DVz gMfOppSjJbT4Q== From: Geliang Tang To: mptcp@lists.linux.dev Cc: Geliang Tang Subject: [PATCH mptcp-next v4 3/5] bpf: Add mptcp_userspace_pm_addr bpf_iter Date: Wed, 8 Jan 2025 16:38:10 +0800 Message-ID: <10551d58b505f20754a13302ce2340e220a3e7a5.1736325184.git.tanggeliang@kylinos.cn> X-Mailer: git-send-email 2.45.2 In-Reply-To: References: Precedence: bulk X-Mailing-List: mptcp@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Geliang Tang Just like the mptcp_subflow bpf_iter used to implement the MPTCP BPF packet scheduler, another bpf_iter is also needed, named mptcp_userspace_pm_addr, to traverse all address entries on userspace_pm_local_addr_list of an MPTCP socket for implementing the MPTCP BPF path manager. In kernel space, we walk this list like this: mptcp_for_each_userspace_pm_addr(msk, entry) kfunc(entry); With the mptcp_userspace_pm_addr bpf_iter, bpf_for_each() can be used to do the same thing in BPF program: bpf_for_each(mptcp_userspace_pm_addr, entry, msk) kfunc(entry); This bpf_iter should be invoked under holding the msk pm lock, so use lockdep_assert_held() to assert the lock is holding. Signed-off-by: Geliang Tang --- net/mptcp/bpf.c | 52 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 52 insertions(+) diff --git a/net/mptcp/bpf.c b/net/mptcp/bpf.c index 923895322b2c..c7f5d208f6cc 100644 --- a/net/mptcp/bpf.c +++ b/net/mptcp/bpf.c @@ -220,6 +220,15 @@ struct bpf_iter_mptcp_subflow_kern { struct list_head *pos; } __aligned(8); +struct bpf_iter_mptcp_userspace_pm_addr { + __u64 __opaque[2]; +} __aligned(8); + +struct bpf_iter_mptcp_userspace_pm_addr_kern { + struct mptcp_sock *msk; + struct list_head *pos; +} __aligned(8); + __bpf_kfunc_start_defs(); __bpf_kfunc static struct mptcp_subflow_context * @@ -273,6 +282,46 @@ bpf_iter_mptcp_subflow_destroy(struct bpf_iter_mptcp_subflow *it) { } +__bpf_kfunc static int +bpf_iter_mptcp_userspace_pm_addr_new(struct bpf_iter_mptcp_userspace_pm_addr *it, + struct mptcp_sock *msk) +{ + struct bpf_iter_mptcp_userspace_pm_addr_kern *kit = (void *)it; + + BUILD_BUG_ON(sizeof(struct bpf_iter_mptcp_userspace_pm_addr_kern) > + sizeof(struct bpf_iter_mptcp_userspace_pm_addr)); + BUILD_BUG_ON(__alignof__(struct bpf_iter_mptcp_userspace_pm_addr_kern) != + __alignof__(struct bpf_iter_mptcp_userspace_pm_addr)); + + kit->msk = msk; + if (!msk) + return -EINVAL; + + if (!spin_is_locked(&msk->pm.lock)) + return -EINVAL; + + kit->pos = &msk->pm.userspace_pm_local_addr_list; + return 0; +} + +__bpf_kfunc static struct mptcp_pm_addr_entry * +bpf_iter_mptcp_userspace_pm_addr_next(struct bpf_iter_mptcp_userspace_pm_addr *it) +{ + struct bpf_iter_mptcp_userspace_pm_addr_kern *kit = (void *)it; + + if (!kit->msk || list_is_last(kit->pos, + &kit->msk->pm.userspace_pm_local_addr_list)) + return NULL; + + kit->pos = kit->pos->next; + return list_entry(kit->pos, struct mptcp_pm_addr_entry, list); +} + +__bpf_kfunc static void +bpf_iter_mptcp_userspace_pm_addr_destroy(struct bpf_iter_mptcp_userspace_pm_addr *it) +{ +} + __bpf_kfunc static struct mptcp_sock *bpf_mptcp_sock_acquire(struct mptcp_sock *msk) { @@ -310,6 +359,9 @@ BTF_ID_FLAGS(func, bpf_mptcp_subflow_ctx, 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) +BTF_ID_FLAGS(func, bpf_iter_mptcp_userspace_pm_addr_new, KF_ITER_NEW | KF_TRUSTED_ARGS) +BTF_ID_FLAGS(func, bpf_iter_mptcp_userspace_pm_addr_next, KF_ITER_NEXT | KF_RET_NULL) +BTF_ID_FLAGS(func, bpf_iter_mptcp_userspace_pm_addr_destroy, KF_ITER_DESTROY) 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)