Bluetooth: mgmt: Introduce mgmt_alloc_skb and mgmt_send_event_skb

This introduces mgmt_alloc_skb and mgmt_send_event_skb which are
convenient when building MGMT events that have variable length as the
likes of skb_put_data can be used to insert portion directly on the skb
instead of having to first build an intermediate buffer just to be
copied over the skb.

Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

diff --git a/include/net/bluetooth/bluetooth.h b/include/net/bluetooth/bluetooth.h
index 2f31e57..7790683 100644 (file)
--- a/include/net/bluetooth/bluetooth.h
+++ b/include/net/bluetooth/bluetooth.h
@@ -390,6 +390,11 @@ struct hci_ctrl {
        };
 };
 
+struct mgmt_ctrl {
+       struct hci_dev *hdev;
+       u16 opcode;
+};
+
 struct bt_skb_cb {
        u8 pkt_type;
        u8 force_active;
@@ -399,6 +404,7 @@ struct bt_skb_cb {
                struct l2cap_ctrl l2cap;
                struct sco_ctrl sco;
                struct hci_ctrl hci;
+               struct mgmt_ctrl mgmt;
        };
 };
 #define bt_cb(skb) ((struct bt_skb_cb *)((skb)->cb))

diff --git a/net/bluetooth/mgmt_util.c b/net/bluetooth/mgmt_util.c
index 83875f2..edee60b 100644 (file)
--- a/net/bluetooth/mgmt_util.c
+++ b/net/bluetooth/mgmt_util.c
@@ -56,40 +56,72 @@ static struct sk_buff *create_monitor_ctrl_event(__le16 index, u32 cookie,
        return skb;
 }
 
-int mgmt_send_event(u16 event, struct hci_dev *hdev, unsigned short channel,
-                   void *data, u16 data_len, int flag, struct sock *skip_sk)
+struct sk_buff *mgmt_alloc_skb(struct hci_dev *hdev, u16 opcode,
+                              unsigned int size)
 {
        struct sk_buff *skb;
-       struct mgmt_hdr *hdr;
 
-       skb = alloc_skb(sizeof(*hdr) + data_len, GFP_KERNEL);
+       skb = alloc_skb(sizeof(struct mgmt_hdr) + size, GFP_KERNEL);
        if (!skb)
-               return -ENOMEM;
+               return skb;
 
-       hdr = skb_put(skb, sizeof(*hdr));
-       hdr->opcode = cpu_to_le16(event);
-       if (hdev)
-               hdr->index = cpu_to_le16(hdev->id);
-       else
-               hdr->index = cpu_to_le16(MGMT_INDEX_NONE);
-       hdr->len = cpu_to_le16(data_len);
+       skb_reserve(skb, sizeof(struct mgmt_hdr));
+       bt_cb(skb)->mgmt.hdev = hdev;
+       bt_cb(skb)->mgmt.opcode = opcode;
 
-       if (data)
-               skb_put_data(skb, data, data_len);
+       return skb;
+}
+
+int mgmt_send_event_skb(unsigned short channel, struct sk_buff *skb, int flag,
+                       struct sock *skip_sk)
+{
+       struct hci_dev *hdev;
+       struct mgmt_hdr *hdr;
+       int len = skb->len;
+
+       if (!skb)
+               return -EINVAL;
+
+       hdev = bt_cb(skb)->mgmt.hdev;
 
        /* Time stamp */
        __net_timestamp(skb);
 
-       hci_send_to_channel(channel, skb, flag, skip_sk);
-
+       /* Send just the data, without headers, to the monitor */
        if (channel == HCI_CHANNEL_CONTROL)
-               hci_send_monitor_ctrl_event(hdev, event, data, data_len,
+               hci_send_monitor_ctrl_event(hdev, bt_cb(skb)->mgmt.opcode,
+                                           skb->data, skb->len,
                                            skb_get_ktime(skb), flag, skip_sk);
 
+       hdr = skb_push(skb, sizeof(*hdr));
+       hdr->opcode = cpu_to_le16(bt_cb(skb)->mgmt.opcode);
+       if (hdev)
+               hdr->index = cpu_to_le16(hdev->id);
+       else
+               hdr->index = cpu_to_le16(MGMT_INDEX_NONE);
+       hdr->len = cpu_to_le16(len);
+
+       hci_send_to_channel(channel, skb, flag, skip_sk);
+
        kfree_skb(skb);
        return 0;
 }
 
+int mgmt_send_event(u16 event, struct hci_dev *hdev, unsigned short channel,
+                   void *data, u16 data_len, int flag, struct sock *skip_sk)
+{
+       struct sk_buff *skb;
+
+       skb = mgmt_alloc_skb(hdev, event, data_len);
+       if (!skb)
+               return -ENOMEM;
+
+       if (data)
+               skb_put_data(skb, data, data_len);
+
+       return mgmt_send_event_skb(channel, skb, flag, skip_sk);
+}
+
 int mgmt_cmd_status(struct sock *sk, u16 index, u16 cmd, u8 status)
 {
        struct sk_buff *skb, *mskb;

diff --git a/net/bluetooth/mgmt_util.h b/net/bluetooth/mgmt_util.h
index 63b965e..98e4039 100644 (file)
--- a/net/bluetooth/mgmt_util.h
+++ b/net/bluetooth/mgmt_util.h
@@ -32,6 +32,10 @@ struct mgmt_pending_cmd {
        int (*cmd_complete)(struct mgmt_pending_cmd *cmd, u8 status);
 };
 
+struct sk_buff *mgmt_alloc_skb(struct hci_dev *hdev, u16 opcode,
+                              unsigned int size);
+int mgmt_send_event_skb(unsigned short channel, struct sk_buff *skb, int flag,
+                       struct sock *skip_sk);
 int mgmt_send_event(u16 event, struct hci_dev *hdev, unsigned short channel,
                    void *data, u16 data_len, int flag, struct sock *skip_sk);
 int mgmt_cmd_status(struct sock *sk, u16 index, u16 cmd, u8 status);