Hi Ying,
On Wed, May 22, 2024 at 7:11 AM Ying Hsu <yinghsu@xxxxxxxxxxxx> wrote:
>
> When HCI raw sockets are opened, the Bluetooth kernel module doesn't
> track CIS/BIS connections. User-space applications have to identify
> ISO data by maintaining connection information and look up the mapping
> for each ACL data packet received. Besides, btsnoop log catpured in
> kernel would couldn't tell ISO data from ACL data in this case.
>
> By differentiating ISO data from ACL data earlier in btusb, we can
> eliminate unnecessary lookups and improve btsnoop log clarity.
> This patch enables vendor-specific differentiation between ISO and
> ACL data packets.
>
> Signed-off-by: Ying Hsu <yinghsu@xxxxxxxxxxxx>
> ---
> Tested LE unicast recording on a ChromeOS device with Intel AX211
>
> drivers/bluetooth/btusb.c | 14 ++++++++++++++
> 1 file changed, 14 insertions(+)
>
> diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c
> index 79aefdb3324d..543961b6c671 100644
> --- a/drivers/bluetooth/btusb.c
> +++ b/drivers/bluetooth/btusb.c
> @@ -889,6 +889,8 @@ struct btusb_data {
> int (*recv_acl)(struct hci_dev *hdev, struct sk_buff *skb);
> int (*recv_bulk)(struct btusb_data *data, void *buffer, int count);
>
> + int (*is_iso_data_pkt)(struct sk_buff *skb);
I'd had this sort of callback in hdev itself so the stack can consult
the driver about packet types at any stage, see bellow.
> +
> int (*setup_on_usb)(struct hci_dev *hdev);
>
> int oob_wake_irq; /* irq for out-of-band wake-on-bt */
> @@ -1229,6 +1231,8 @@ static int btusb_recv_bulk(struct btusb_data *data, void *buffer, int count)
>
> if (!hci_skb_expect(skb)) {
> /* Complete frame */
> + if (data->is_iso_data_pkt && data->is_iso_data_pkt(skb))
> + hci_skb_pkt_type(skb) = HCI_ISODATA_PKT;
Id keep a single point in the stack doing the reclassification of the
packets, which should probably be in hci_recv_frame, Id suggesting
doing something like:
diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c
index b3ee9ff17624..505ef0b58f8c 100644
--- a/net/bluetooth/hci_core.c
+++ b/net/bluetooth/hci_core.c
@@ -2941,6 +2941,14 @@ int hci_reset_dev(struct hci_dev *hdev)
}
EXPORT_SYMBOL(hci_reset_dev);
+static u8 hci_pkt_type(struct hic_dev *dev, struct sk_buff *skb)
+{
+ if (hdev->pkt_type)
+ return hdev->pkt_type(dev, skb);
+
+ return hci_skb_pkt_type(skb);
+}
+
/* Receive frame from HCI drivers */
int hci_recv_frame(struct hci_dev *hdev, struct sk_buff *skb)
{
@@ -2950,6 +2958,10 @@ int hci_recv_frame(struct hci_dev *hdev, struct
sk_buff *skb)
return -ENXIO;
}
+ /* Check if the driver agree with packet type classification */
+ if (hci_skb_pkt_type(skb) != hci_pkt_type(skb))
+ hci_skb_pkt_type(skb) = hci_pkt_type(skb);
+
switch (hci_skb_pkt_type(skb)) {
case HCI_EVENT_PKT:
break;
> btusb_recv_acl(data, skb);
> skb = NULL;
> }
> @@ -2539,6 +2543,13 @@ static int btusb_recv_bulk_intel(struct btusb_data *data, void *buffer,
> return btusb_recv_bulk(data, buffer, count);
> }
>
> +static int btusb_is_iso_data_pkt_intel(struct sk_buff *skb)
> +{
> + __u16 handle = (__le16_to_cpu(hci_acl_hdr(skb)->handle) & 0xfff);
> +
> + return (handle >= 0x900);
> +}
> +
> static int btusb_send_frame_intel(struct hci_dev *hdev, struct sk_buff *skb)
> {
> struct urb *urb;
> @@ -4361,6 +4372,9 @@ static int btusb_probe(struct usb_interface *intf,
> /* Override the rx handlers */
> data->recv_event = btintel_recv_event;
> data->recv_bulk = btusb_recv_bulk_intel;
> +
> + /* Override for ISO data packet*/
> + data->is_iso_data_pkt = btusb_is_iso_data_pkt_intel;
> } else if (id->driver_info & BTUSB_REALTEK) {
> /* Allocate extra space for Realtek device */
> priv_size += sizeof(struct btrealtek_data);
> --
> 2.45.1.288.g0e0cd299f1-goog
>
--
Luiz Augusto von Dentz
