From nobody Sat Nov 23 13:39:13 2024 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 DC14619ADBF for ; Thu, 10 Oct 2024 05:48:10 +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=1728539290; cv=none; b=NGzq/1bdHouThztHoc1qGRd80DBlGVpupu8MNcmeqTSoIZ5GqdtheVoiK4VM9YO7A8iqsE5CPH2oRXxPw48urCPVk1wD2atLHYaBrKdEhP66QyxY60cF/eftPUUn2tD89x3ZsmEMYPidd1O7I3bb78e182MHJqhb2KDGXgpnhtY= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728539290; c=relaxed/simple; bh=geYo1LdaKbKJddp+fZP2ZjVF6smiw/+2ce+tHOgdWd0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=uNryqIcmGalQs3+nUt6NQ+jk87pcHjYH6kFen4I6uwi4lNF654k7s0qJ6jSrbyzpx4Q1E7GUGMpCNvg34FeQ5N4M7iG5E6toN+Y0qUcp/MAdUJ8YwJjnsrcporWTnVi7geC26lM+atobkYl00VwULmtprIInI4U3l/BNj04l/vQ= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=lJxuNUaR; 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="lJxuNUaR" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 40D35C4CEC5; Thu, 10 Oct 2024 05:48:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1728539290; bh=geYo1LdaKbKJddp+fZP2ZjVF6smiw/+2ce+tHOgdWd0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=lJxuNUaR3NQyopZzanHmNWVBmnyZi4qtKRZhAAIEdJdNKm2I9FeFOGKXAqWcuZ5sF WlN1tFSH0FYTNZQ48uh47WBNzkrpp4qJ8mgrgVgHS8ENYl8F16kcb+H7Wn98MiJh+A mNQbWEbTtIT6cKNi935Ittq2mXPn2hbKsZ8IsQu4UtwD1FXeUV1uPCpqcu29YUr16o 5BQyr+ffvqOLVfyYpL8a87zSKfZ+pcT5NcAj5GPBkijuNDgyASW+/dWoWAzh/BIJcr 4OAOEs/nnZUBVYMtzF3jK+n8lI6wAEd0DJwzzBDmJRtMf1GWJDK7dRU0gudUaM5zFK DJ4XgoP3IMqrQ== From: Geliang Tang To: mptcp@lists.linux.dev Cc: Geliang Tang Subject: [PATCH mptcp-next v3 02/15] mptcp: add addr parameter for get_addr Date: Thu, 10 Oct 2024 13:47:47 +0800 Message-ID: X-Mailer: git-send-email 2.43.0 In-Reply-To: References: Precedence: bulk X-Mailing-List: mptcp@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: Geliang Tang The netlink messages are sent both in mptcp_pm_nl_get_addr() and mptcp_userspace_pm_get_addr(), this makes the code somewhat repetitive. This is because the netlink PM and userspace PM use different locks to protect the address entry that needs to be sent via the netlink message. The former uses pernet->lock, and the latter uses msk->pm.lock. The current get_addr() flow looks like this: lock(); entry =3D get_entry(); send_nlmsg(entry); unlock(); After holding the lock, get the entry from the list, send the entry, and finally release the lock. This patch changes the process by getting the entry while holding the lock, then making a copy of the entry so that the lock can be released. Finally, the copy of the entry is sent without locking: lock(); entry =3D get_entry(); *copy =3D *entry; unlock(); send_nlmsg(copy); This way we can reuse this send_nlmsg() code between the netlink PM and userspace PM. Signed-off-by: Geliang Tang --- net/mptcp/pm_netlink.c | 33 ++++++++++++++++++--------------- net/mptcp/pm_userspace.c | 24 +++++++++++++----------- net/mptcp/protocol.h | 3 ++- 3 files changed, 33 insertions(+), 27 deletions(-) diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c index c65d0ac4acc2..76c4520f7cb5 100644 --- a/net/mptcp/pm_netlink.c +++ b/net/mptcp/pm_netlink.c @@ -1792,13 +1792,14 @@ int mptcp_nl_fill_addr(struct sk_buff *skb, return -EMSGSIZE; } =20 -static int mptcp_pm_nl_get_addr(u8 id, struct genl_info *info) +static int mptcp_pm_nl_get_addr(u8 id, struct mptcp_pm_addr_entry *addr, + struct genl_info *info) { struct pm_nl_pernet *pernet =3D genl_info_pm_nl(info); struct mptcp_pm_addr_entry *entry; struct sk_buff *msg; + int ret =3D -EINVAL; void *reply; - int ret; =20 msg =3D nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); if (!msg) @@ -1814,34 +1815,36 @@ static int mptcp_pm_nl_get_addr(u8 id, struct genl_= info *info) =20 spin_lock_bh(&pernet->lock); entry =3D __lookup_addr_by_id(pernet, id); - if (!entry) { + if (entry) { + *addr =3D *entry; + ret =3D 0; + } + spin_unlock_bh(&pernet->lock); + + if (ret) { GENL_SET_ERR_MSG(info, "address not found"); - ret =3D -EINVAL; - goto unlock_fail; + goto fail; } =20 - ret =3D mptcp_nl_fill_addr(msg, entry); + ret =3D mptcp_nl_fill_addr(msg, addr); if (ret) - goto unlock_fail; + goto fail; =20 genlmsg_end(msg, reply); ret =3D genlmsg_reply(msg, info); - spin_unlock_bh(&pernet->lock); return ret; =20 -unlock_fail: - spin_unlock_bh(&pernet->lock); - fail: nlmsg_free(msg); return ret; } =20 -static int mptcp_pm_get_addr(u8 id, struct genl_info *info) +static int mptcp_pm_get_addr(u8 id, struct mptcp_pm_addr_entry *addr, + struct genl_info *info) { if (info->attrs[MPTCP_PM_ATTR_TOKEN]) - return mptcp_userspace_pm_get_addr(id, info); - return mptcp_pm_nl_get_addr(id, info); + return mptcp_userspace_pm_get_addr(id, addr, info); + return mptcp_pm_nl_get_addr(id, addr, info); } =20 int mptcp_pm_nl_get_addr_doit(struct sk_buff *skb, struct genl_info *info) @@ -1854,7 +1857,7 @@ int mptcp_pm_nl_get_addr_doit(struct sk_buff *skb, st= ruct genl_info *info) if (ret < 0) return ret; =20 - ret =3D mptcp_pm_get_addr(addr.addr.id, info); + ret =3D mptcp_pm_get_addr(addr.addr.id, &addr, info); return ret; } =20 diff --git a/net/mptcp/pm_userspace.c b/net/mptcp/pm_userspace.c index da617d8bcc09..5c9f740bd9ac 100644 --- a/net/mptcp/pm_userspace.c +++ b/net/mptcp/pm_userspace.c @@ -629,7 +629,8 @@ int mptcp_userspace_pm_dump_addr(struct sk_buff *msg, return ret; } =20 -int mptcp_userspace_pm_get_addr(u8 id, struct genl_info *info) +int mptcp_userspace_pm_get_addr(u8 id, struct mptcp_pm_addr_entry *addr, + struct genl_info *info) { struct mptcp_pm_addr_entry *entry; struct mptcp_sock *msk; @@ -661,26 +662,27 @@ int mptcp_userspace_pm_get_addr(u8 id, struct genl_in= fo *info) lock_sock(sk); spin_lock_bh(&msk->pm.lock); entry =3D mptcp_userspace_pm_lookup_addr_by_id(msk, id); - if (!entry) { + if (entry) { + *addr =3D *entry; + ret =3D 0; + } + spin_unlock_bh(&msk->pm.lock); + release_sock(sk); + + if (ret) { GENL_SET_ERR_MSG(info, "address not found"); - ret =3D -EINVAL; - goto unlock_fail; + goto fail; } =20 - ret =3D mptcp_nl_fill_addr(msg, entry); + ret =3D mptcp_nl_fill_addr(msg, addr); if (ret) - goto unlock_fail; + goto fail; =20 genlmsg_end(msg, reply); ret =3D genlmsg_reply(msg, info); - spin_unlock_bh(&msk->pm.lock); - release_sock(sk); sock_put(sk); return ret; =20 -unlock_fail: - spin_unlock_bh(&msk->pm.lock); - release_sock(sk); fail: nlmsg_free(msg); out: diff --git a/net/mptcp/protocol.h b/net/mptcp/protocol.h index 73ef3087555c..e5319876c5f6 100644 --- a/net/mptcp/protocol.h +++ b/net/mptcp/protocol.h @@ -1125,7 +1125,8 @@ bool mptcp_pm_nl_is_backup(struct mptcp_sock *msk, st= ruct mptcp_addr_info *skc); bool mptcp_userspace_pm_is_backup(struct mptcp_sock *msk, struct mptcp_add= r_info *skc); int mptcp_userspace_pm_dump_addr(struct sk_buff *msg, struct netlink_callback *cb); -int mptcp_userspace_pm_get_addr(u8 id, struct genl_info *info); +int mptcp_userspace_pm_get_addr(u8 id, struct mptcp_pm_addr_entry *addr, + struct genl_info *info); =20 static inline u8 subflow_get_local_id(const struct mptcp_subflow_context *= subflow) { --=20 2.43.0