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?
> #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
