From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B2F93C10DCE for ; Wed, 18 Mar 2020 11:13:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 87F5D20771 for ; Wed, 18 Mar 2020 11:13:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727758AbgCRLN5 convert rfc822-to-8bit (ORCPT ); Wed, 18 Mar 2020 07:13:57 -0400 Received: from coyote.holtmann.net ([212.227.132.17]:43213 "EHLO mail.holtmann.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727113AbgCRLN4 (ORCPT ); Wed, 18 Mar 2020 07:13:56 -0400 Received: from marcel-macbook.fritz.box (p4FEFC5A7.dip0.t-ipconnect.de [79.239.197.167]) by mail.holtmann.org (Postfix) with ESMTPSA id BC512CECF3; Wed, 18 Mar 2020 12:23:25 +0100 (CET) Content-Type: text/plain; charset=us-ascii Mime-Version: 1.0 (Mac OS X Mail 13.0 \(3608.60.0.2.5\)) Subject: Re: [PATCH 1/2] Bluetooth: L2CAP: Use DEFER_SETUP to group ECRED connections From: Marcel Holtmann In-Reply-To: <20200312222454.5079-2-luiz.dentz@gmail.com> Date: Wed, 18 Mar 2020 12:13:55 +0100 Cc: linux-bluetooth@vger.kernel.org Content-Transfer-Encoding: 8BIT Message-Id: References: <20200312222454.5079-1-luiz.dentz@gmail.com> <20200312222454.5079-2-luiz.dentz@gmail.com> To: Luiz Augusto von Dentz X-Mailer: Apple Mail (2.3608.60.0.2.5) Sender: linux-bluetooth-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-bluetooth@vger.kernel.org Hi Luiz, > This uses the DEFER_SETUP flag to group channels with > L2CAP_CREDIT_BASED_CONNECTION_REQ. > > Signed-off-by: Luiz Augusto von Dentz > --- > include/net/bluetooth/l2cap.h | 5 ++ > net/bluetooth/l2cap_core.c | 130 +++++++++++++++++++++++++++++++--- > net/bluetooth/l2cap_sock.c | 13 ++-- > 3 files changed, 133 insertions(+), 15 deletions(-) > > diff --git a/include/net/bluetooth/l2cap.h b/include/net/bluetooth/l2cap.h > index 537aaead259f..dada14d0622c 100644 > --- a/include/net/bluetooth/l2cap.h > +++ b/include/net/bluetooth/l2cap.h > @@ -47,6 +47,7 @@ > #define L2CAP_DEFAULT_ACC_LAT 0xFFFFFFFF > #define L2CAP_BREDR_MAX_PAYLOAD 1019 /* 3-DH5 packet */ > #define L2CAP_LE_MIN_MTU 23 > +#define L2CAP_ECRED_CONN_SCID_MAX 5 > > #define L2CAP_DISC_TIMEOUT msecs_to_jiffies(100) > #define L2CAP_DISC_REJ_TIMEOUT msecs_to_jiffies(5000) > @@ -660,6 +661,7 @@ struct l2cap_ops { > void (*suspend) (struct l2cap_chan *chan); > void (*set_shutdown) (struct l2cap_chan *chan); > long (*get_sndtimeo) (struct l2cap_chan *chan); > + struct pid *(*get_peer_pid) (struct l2cap_chan *chan); I would move this support into a separate patch. I think that can be applied independently. > struct sk_buff *(*alloc_skb) (struct l2cap_chan *chan, > unsigned long hdr_len, > unsigned long len, int nb); > @@ -983,6 +985,9 @@ void l2cap_chan_set_defaults(struct l2cap_chan *chan); > int l2cap_ertm_init(struct l2cap_chan *chan); > void l2cap_chan_add(struct l2cap_conn *conn, struct l2cap_chan *chan); > void __l2cap_chan_add(struct l2cap_conn *conn, struct l2cap_chan *chan); > +typedef void (*l2cap_chan_func_t)(struct l2cap_chan *chan, void *data); > +void l2cap_chan_list(struct l2cap_conn *conn, l2cap_chan_func_t func, > + void *data); > void l2cap_chan_del(struct l2cap_chan *chan, int err); > void l2cap_send_conn_req(struct l2cap_chan *chan); > void l2cap_move_start(struct l2cap_chan *chan); > diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c > index 5e6e35ab44dd..20c1d5f9c238 100644 > --- a/net/bluetooth/l2cap_core.c > +++ b/net/bluetooth/l2cap_core.c > @@ -678,6 +678,29 @@ void l2cap_chan_del(struct l2cap_chan *chan, int err) > } > EXPORT_SYMBOL_GPL(l2cap_chan_del); > > +static void __l2cap_chan_list(struct l2cap_conn *conn, l2cap_chan_func_t func, > + void *data) > +{ > + struct l2cap_chan *chan; > + > + list_for_each_entry(chan, &conn->chan_l, list) { > + func(chan, data); > + } > +} > + > +void l2cap_chan_list(struct l2cap_conn *conn, l2cap_chan_func_t func, > + void *data) > +{ > + if (!conn) > + return; > + > + mutex_lock(&conn->chan_lock); > + __l2cap_chan_list(conn, func, data); > + mutex_unlock(&conn->chan_lock); > +} > + > +EXPORT_SYMBOL_GPL(l2cap_chan_list); > + > static void l2cap_conn_update_id_addr(struct work_struct *work) > { > struct l2cap_conn *conn = container_of(work, struct l2cap_conn, > @@ -1356,29 +1379,77 @@ static void l2cap_le_connect(struct l2cap_chan *chan) > sizeof(req), &req); > } > > -static void l2cap_ecred_connect(struct l2cap_chan *chan) > -{ > - struct l2cap_conn *conn = chan->conn; > +struct l2cap_ecred_conn_data { > struct { > struct l2cap_ecred_conn_req req; > - __le16 scid; > + __le16 scid[5]; > } __packed pdu; > + struct l2cap_chan *chan; > + struct pid *pid; > + int count; > +}; > + > +static void l2cap_ecred_defer_connect(struct l2cap_chan *chan, void *data) > +{ > + struct l2cap_ecred_conn_data *conn = data; > + struct pid *pid; > + > + if (chan == conn->chan) > + return; > + > + if (!test_and_clear_bit(FLAG_DEFER_SETUP, &chan->flags)) > + return; > + > + pid = chan->ops->get_peer_pid(chan); > + > + /* Only add deferred channels with the same PID/PSM */ > + if (conn->pid != pid || chan->psm != conn->chan->psm || chan->ident || > + chan->mode != L2CAP_MODE_EXT_FLOWCTL || chan->state != BT_CONNECT) > + return; > + > + if (test_and_set_bit(FLAG_ECRED_CONN_REQ_SENT, &chan->flags)) > + return; > + > + /* Set the same ident so we can match on the rsp */ > + chan->ident = conn->chan->ident; > + > + /* Include all channels deferred */ > + conn->pdu.scid[conn->count] = cpu_to_le16(chan->scid); > + > + conn->count++; > +} > + > +static void l2cap_ecred_connect(struct l2cap_chan *chan) > +{ > + struct l2cap_conn *conn = chan->conn; > + struct l2cap_ecred_conn_data data; > + > + if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) > + return; > > if (test_and_set_bit(FLAG_ECRED_CONN_REQ_SENT, &chan->flags)) > return; > > l2cap_ecred_init(chan, 0); > > - pdu.req.psm = chan->psm; > - pdu.req.mtu = cpu_to_le16(chan->imtu); > - pdu.req.mps = cpu_to_le16(chan->mps); > - pdu.req.credits = cpu_to_le16(chan->rx_credits); > - pdu.scid = cpu_to_le16(chan->scid); > + data.pdu.req.psm = chan->psm; > + data.pdu.req.mtu = cpu_to_le16(chan->imtu); > + data.pdu.req.mps = cpu_to_le16(chan->mps); > + data.pdu.req.credits = cpu_to_le16(chan->rx_credits); > + data.pdu.scid[0] = cpu_to_le16(chan->scid); > > chan->ident = l2cap_get_ident(conn); > + data.pid = chan->ops->get_peer_pid(chan); > + > + data.count = 1; > + data.chan = chan; > + data.pid = chan->ops->get_peer_pid(chan); > + > + __l2cap_chan_list(conn, l2cap_ecred_defer_connect, &data); > > l2cap_send_cmd(conn, chan->ident, L2CAP_ECRED_CONN_REQ, > - sizeof(pdu), &pdu); > + sizeof(data.pdu.req) + data.count * sizeof(__le16), > + &data.pdu); > } > > static void l2cap_le_start(struct l2cap_chan *chan) > @@ -7694,6 +7765,29 @@ static bool is_valid_psm(u16 psm, u8 dst_type) { > return ((psm & 0x0101) == 0x0001); > } > > +struct l2cap_chan_data { > + struct l2cap_chan *chan; > + struct pid *pid; > + int count; > +}; > + > +static void l2cap_chan_by_pid(struct l2cap_chan *chan, void *data) > +{ > + struct l2cap_chan_data *d = data; > + > + if (chan == d->chan) > + return; > + > + /* Only count deferred channels with the same PID/PSM */ > + if (d->pid != chan->ops->get_peer_pid(chan) || > + !test_bit(FLAG_DEFER_SETUP, &chan->flags) || > + chan->psm != d->chan->psm || chan->ident || > + chan->state != BT_CONNECT) > + return; > + > + d->count++; > +} > + > int l2cap_chan_connect(struct l2cap_chan *chan, __le16 psm, u16 cid, > bdaddr_t *dst, u8 dst_type) > { > @@ -7813,6 +7907,22 @@ int l2cap_chan_connect(struct l2cap_chan *chan, __le16 psm, u16 cid, > goto done; > } > > + if (chan->mode == L2CAP_MODE_EXT_FLOWCTL) { > + struct l2cap_chan_data data; > + > + data.chan = chan; > + data.pid = chan->ops->get_peer_pid(chan); > + data.count = 0; > + > + l2cap_chan_list(conn, l2cap_chan_by_pid, &data); > + /* Check if there isn't too many channels being connected */ > + if (!(data.count < L2CAP_ECRED_CONN_SCID_MAX - 1)) { > + hci_conn_drop(hcon); > + err = -EPROTO; > + goto done; > + } > + } > + > mutex_lock(&conn->chan_lock); > l2cap_chan_lock(chan); > > diff --git a/net/bluetooth/l2cap_sock.c b/net/bluetooth/l2cap_sock.c > index 40fb10b591bd..e43a90e05972 100644 > --- a/net/bluetooth/l2cap_sock.c > +++ b/net/bluetooth/l2cap_sock.c > @@ -549,11 +549,6 @@ static int l2cap_sock_getsockopt(struct socket *sock, int level, int optname, > break; > > case BT_DEFER_SETUP: > - if (sk->sk_state != BT_BOUND && sk->sk_state != BT_LISTEN) { > - err = -EINVAL; > - break; > - } > - I removing this really a good idea. I think it is not really so bad to force at least BT_BOUND so that a local controller has been at least somehow selected. Just doing setsockopt(DEFER_SETUP) and then connect() seems weird. Let us force the application to at least bind the local controller for this specific usage. They can still bind with BDADDR_ANY, but that gives us a bit cleaner state handling. > if (put_user(test_bit(BT_SK_DEFER_SETUP, &bt_sk(sk)->flags), > (u32 __user *) optval)) > err = -EFAULT; > @@ -1504,6 +1499,13 @@ static long l2cap_sock_get_sndtimeo_cb(struct l2cap_chan *chan) > return sk->sk_sndtimeo; > } > > +static struct pid *l2cap_sock_get_peer_pid_cb(struct l2cap_chan *chan) > +{ > + struct sock *sk = chan->data; > + > + return sk->sk_peer_pid; > +} > + > static void l2cap_sock_suspend_cb(struct l2cap_chan *chan) > { > struct sock *sk = chan->data; > @@ -1525,6 +1527,7 @@ static const struct l2cap_ops l2cap_chan_ops = { > .suspend = l2cap_sock_suspend_cb, > .set_shutdown = l2cap_sock_set_shutdown_cb, > .get_sndtimeo = l2cap_sock_get_sndtimeo_cb, > + .get_peer_pid = l2cap_sock_get_peer_pid_cb, > .alloc_skb = l2cap_sock_alloc_skb_cb, > }; Regards Marcel