2020-05-25 21:49:14

by Alain Michaud

[permalink] [raw]
Subject: [PATCH v2] sco:Add support for BT_PKT_STATUS CMSG data

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 <[email protected]>

---

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 | 28 ++++++++++++++++++++++++++++
5 files changed, 43 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
+
#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..3d7b973e5b7b 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 +450,19 @@ 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)
+{
+ __u32 mask = sco_pi(sk)->cmsg_mask;
+
+ if (mask & SCO_CMSG_PKT_STATUS) {
+ int pkt_status = bt_cb(skb)->sco.pkt_status;
+
+ put_cmsg(msg, SOL_BLUETOOTH, BT_PKT_STATUS, sizeof(pkt_status),
+ &pkt_status);
+ }
+}
+
static void sco_sock_init(struct sock *sk, struct sock *parent)
{
BT_DBG("sk %p", sk);
@@ -457,6 +471,8 @@ 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 +862,18 @@ 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, (int __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;
--
2.27.0.rc0.183.gde8f92d652-goog


2020-05-28 08:27:09

by Marcel Holtmann

[permalink] [raw]
Subject: Re: [PATCH v2] sco:Add support for BT_PKT_STATUS CMSG data

Hi Alain,

> 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 <[email protected]>
>
> ---
>
> 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 | 28 ++++++++++++++++++++++++++++
> 5 files changed, 43 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
> +

we need to agree on if this is an int or u8 value. Otherwise this looks good.

Regards

Marcel

2020-05-28 13:29:57

by Alain Michaud

[permalink] [raw]
Subject: Re: [PATCH v2] sco:Add support for BT_PKT_STATUS CMSG data

On Thu, May 28, 2020 at 4:26 AM Marcel Holtmann <[email protected]> wrote:
>
> Hi Alain,
>
> > 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 <[email protected]>
> >
> > ---
> >
> > 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 | 28 ++++++++++++++++++++++++++++
> > 5 files changed, 43 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
> > +
>
> we need to agree on if this is an int or u8 value. Otherwise this looks good.
Since doing anything beyond a u8 value would require a core spec
change and likely a new definition for what the packet flags are, I
think it is likely safe to keep as u8. Do you have a different
perspective?
>
> Regards
>
> Marcel
>