Hi Luiz
On Wed, Jun 3, 2020 at 5:15 PM Luiz Augusto von Dentz
<luiz.dentz@xxxxxxxxx> wrote:
>
> Hi Alain, Marcel,
>
> On Wed, Jun 3, 2020 at 7:56 AM Alain Michaud <alainm@xxxxxxxxxxxx> wrote:
> >
> > This change adds support for reporting the BT_PKT_STATUS to the socket
> > CMSG data to allow the implementation of a packet loss correction on
> > erronous data received on the SCO socket.
> >
> > The patch was partially developed by Marcel Holtmann and validated by
> > Hsin-yu Chao
> >
> > Signed-off-by: Alain Michaud <alainm@xxxxxxxxxxxx>
> >
> > ---
> >
> > include/net/bluetooth/bluetooth.h | 8 +++++++
> > include/net/bluetooth/sco.h | 3 +++
> > net/bluetooth/af_bluetooth.c | 3 +++
> > net/bluetooth/hci_core.c | 1 +
> > net/bluetooth/sco.c | 35 +++++++++++++++++++++++++++++++
> > 5 files changed, 50 insertions(+)
> >
> > diff --git a/include/net/bluetooth/bluetooth.h b/include/net/bluetooth/bluetooth.h
> > index 3fa7b1e3c5d9..85e6c5754448 100644
> > --- a/include/net/bluetooth/bluetooth.h
> > +++ b/include/net/bluetooth/bluetooth.h
> > @@ -147,6 +147,8 @@ struct bt_voice {
> > #define BT_MODE_LE_FLOWCTL 0x03
> > #define BT_MODE_EXT_FLOWCTL 0x04
> >
> > +#define BT_PKT_STATUS 16
> > +
> > __printf(1, 2)
> > void bt_info(const char *fmt, ...);
> > __printf(1, 2)
> > @@ -275,6 +277,7 @@ struct bt_sock {
> > struct sock *parent;
> > unsigned long flags;
> > void (*skb_msg_name)(struct sk_buff *, void *, int *);
> > + void (*skb_put_cmsg)(struct sk_buff *, struct msghdr *, struct sock *);
> > };
> >
> > enum {
> > @@ -324,6 +327,10 @@ struct l2cap_ctrl {
> > struct l2cap_chan *chan;
> > };
> >
> > +struct sco_ctrl {
> > + u8 pkt_status;
> > +};
> > +
> > struct hci_dev;
> >
> > typedef void (*hci_req_complete_t)(struct hci_dev *hdev, u8 status, u16 opcode);
> > @@ -350,6 +357,7 @@ struct bt_skb_cb {
> > u8 incoming:1;
> > union {
> > struct l2cap_ctrl l2cap;
> > + struct sco_ctrl sco;
> > struct hci_ctrl hci;
> > };
> > };
> > diff --git a/include/net/bluetooth/sco.h b/include/net/bluetooth/sco.h
> > index f40ddb4264fc..7f0d7bdc53f6 100644
> > --- a/include/net/bluetooth/sco.h
> > +++ b/include/net/bluetooth/sco.h
> > @@ -46,4 +46,7 @@ struct sco_conninfo {
> > __u8 dev_class[3];
> > };
> >
> > +/* CMSG flags */
> > +#define SCO_CMSG_PKT_STATUS 0x0001
> > +
>
> I wonder if we can make this generic since ISO also has similar status
> of received packets so I was hoping I could reuse the same flag to
> indicate we want packet status to be transmitted with cmsg. Maybe have
> it as BT_CMSG_PKT_STATUS?
I think CMSG flags will be different based on the socket types. I
agree it's possible some will be shared between SCO and ISO, but I
would hesitate to make this generic to BT since it doesn't apply to
all BT sockets. This also isn't exposed to external components
either, it's sort of a SCO internal implementation detail more than
anything. ISO could have something similar and likely other flags...
>
> > #endif /* __SCO_H */
> > diff --git a/net/bluetooth/af_bluetooth.c b/net/bluetooth/af_bluetooth.c
> > index 3fd124927d4d..d0abea8d08cc 100644
> > --- a/net/bluetooth/af_bluetooth.c
> > +++ b/net/bluetooth/af_bluetooth.c
> > @@ -286,6 +286,9 @@ int bt_sock_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
> > if (msg->msg_name && bt_sk(sk)->skb_msg_name)
> > bt_sk(sk)->skb_msg_name(skb, msg->msg_name,
> > &msg->msg_namelen);
> > +
> > + if (bt_sk(sk)->skb_put_cmsg)
> > + bt_sk(sk)->skb_put_cmsg(skb, msg, sk);
> > }
> >
> > skb_free_datagram(sk, skb);
> > diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c
> > index 51d399273276..7b5e46198d99 100644
> > --- a/net/bluetooth/hci_core.c
> > +++ b/net/bluetooth/hci_core.c
> > @@ -4549,6 +4549,7 @@ static void hci_scodata_packet(struct hci_dev *hdev, struct sk_buff *skb)
> >
> > if (conn) {
> > /* Send to upper protocol */
> > + bt_cb(skb)->sco.pkt_status = flags & 0x03;
> > sco_recv_scodata(conn, skb);
> > return;
> > } else {
> > diff --git a/net/bluetooth/sco.c b/net/bluetooth/sco.c
> > index c8c3d38cdc7b..f6b54853e547 100644
> > --- a/net/bluetooth/sco.c
> > +++ b/net/bluetooth/sco.c
> > @@ -66,6 +66,7 @@ struct sco_pinfo {
> > bdaddr_t dst;
> > __u32 flags;
> > __u16 setting;
> > + __u32 cmsg_mask;
> > struct sco_conn *conn;
> > };
> >
> > @@ -449,6 +450,15 @@ static void sco_sock_close(struct sock *sk)
> > sco_sock_kill(sk);
> > }
> >
> > +static void sco_skb_put_cmsg(struct sk_buff *skb, struct msghdr *msg,
> > + struct sock *sk)
> > +{
> > + if (sco_pi(sk)->cmsg_mask & SCO_CMSG_PKT_STATUS)
> > + put_cmsg(msg, SOL_BLUETOOTH, BT_PKT_STATUS,
> > + sizeof(bt_cb(skb)->sco.pkt_status),
> > + &bt_cb(skb)->sco.pkt_status);
> > +}
> > +
> > static void sco_sock_init(struct sock *sk, struct sock *parent)
> > {
> > BT_DBG("sk %p", sk);
> > @@ -457,6 +467,8 @@ static void sco_sock_init(struct sock *sk, struct sock *parent)
> > sk->sk_type = parent->sk_type;
> > bt_sk(sk)->flags = bt_sk(parent)->flags;
> > security_sk_clone(parent, sk);
> > + } else {
> > + bt_sk(sk)->skb_put_cmsg = sco_skb_put_cmsg;
> > }
> > }
> >
> > @@ -846,6 +858,18 @@ static int sco_sock_setsockopt(struct socket *sock, int level, int optname,
> > sco_pi(sk)->setting = voice.setting;
> > break;
> >
> > + case BT_PKT_STATUS:
> > + if (get_user(opt, (u32 __user *)optval)) {
> > + err = -EFAULT;
> > + break;
> > + }
> > +
> > + if (opt)
> > + sco_pi(sk)->cmsg_mask |= SCO_CMSG_PKT_STATUS;
> > + else
> > + sco_pi(sk)->cmsg_mask &= ~SCO_CMSG_PKT_STATUS;
> > + break;
> > +
> > default:
> > err = -ENOPROTOOPT;
> > break;
> > @@ -923,6 +947,7 @@ static int sco_sock_getsockopt(struct socket *sock, int level, int optname,
> > int len, err = 0;
> > struct bt_voice voice;
> > u32 phys;
> > + u32 pkt_status;
> >
> > BT_DBG("sk %p", sk);
> >
> > @@ -969,6 +994,16 @@ static int sco_sock_getsockopt(struct socket *sock, int level, int optname,
> > err = -EFAULT;
> > break;
> >
> > + case BT_PKT_STATUS:
> > + if (sco_pi(sk)->cmsg_mask & SCO_CMSG_PKT_STATUS)
> > + pkt_status = 1;
> > + else
> > + pkt_status = 0;
> > +
> > + if (put_user(pkt_status, (u32 __user *)optval))
> > + err = -EFAULT;
> > + break;
> > +
> > default:
> > err = -ENOPROTOOPT;
> > break;
> > --
> > 2.27.0.rc2.251.g90737beb825-goog
> >
>
>
> --
> Luiz Augusto von Dentz
