[Bluetooth] Add hci_recv_fragment() helper function
Most drivers must handle fragmented HCI data packets and events. This
patch adds a generic function for their reassembly to the Bluetooth
core layer and thus allows to shrink the complexity of the drivers.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c
index aa4b56a..9c71cff 100644
--- a/net/bluetooth/hci_core.c
+++ b/net/bluetooth/hci_core.c
@@ -826,7 +826,7 @@
int hci_register_dev(struct hci_dev *hdev)
{
struct list_head *head = &hci_dev_list, *p;
- int id = 0;
+ int i, id = 0;
BT_DBG("%p name %s type %d owner %p", hdev, hdev->name, hdev->type, hdev->owner);
@@ -865,6 +865,9 @@
skb_queue_head_init(&hdev->cmd_q);
skb_queue_head_init(&hdev->raw_q);
+ for (i = 0; i < 3; i++)
+ hdev->reassembly[i] = NULL;
+
init_waitqueue_head(&hdev->req_wait_q);
init_MUTEX(&hdev->req_lock);
@@ -889,6 +892,8 @@
/* Unregister HCI device */
int hci_unregister_dev(struct hci_dev *hdev)
{
+ int i;
+
BT_DBG("%p name %s type %d", hdev, hdev->name, hdev->type);
hci_unregister_sysfs(hdev);
@@ -899,9 +904,13 @@
hci_dev_do_close(hdev);
+ for (i = 0; i < 3; i++)
+ kfree_skb(hdev->reassembly[i]);
+
hci_notify(hdev, HCI_DEV_UNREG);
__hci_dev_put(hdev);
+
return 0;
}
EXPORT_SYMBOL(hci_unregister_dev);
@@ -922,6 +931,90 @@
}
EXPORT_SYMBOL(hci_resume_dev);
+/* Receive packet type fragment */
+#define __reassembly(hdev, type) ((hdev)->reassembly[(type) - 2])
+
+int hci_recv_fragment(struct hci_dev *hdev, int type, void *data, int count)
+{
+ if (type < HCI_ACLDATA_PKT || type > HCI_EVENT_PKT)
+ return -EILSEQ;
+
+ while (count) {
+ struct sk_buff *skb = __reassembly(hdev, type);
+ struct { int expect; } *scb;
+ int len = 0;
+
+ if (!skb) {
+ /* Start of the frame */
+
+ switch (type) {
+ case HCI_EVENT_PKT:
+ if (count >= HCI_EVENT_HDR_SIZE) {
+ struct hci_event_hdr *h = data;
+ len = HCI_EVENT_HDR_SIZE + h->plen;
+ } else
+ return -EILSEQ;
+ break;
+
+ case HCI_ACLDATA_PKT:
+ if (count >= HCI_ACL_HDR_SIZE) {
+ struct hci_acl_hdr *h = data;
+ len = HCI_ACL_HDR_SIZE + __le16_to_cpu(h->dlen);
+ } else
+ return -EILSEQ;
+ break;
+
+ case HCI_SCODATA_PKT:
+ if (count >= HCI_SCO_HDR_SIZE) {
+ struct hci_sco_hdr *h = data;
+ len = HCI_SCO_HDR_SIZE + h->dlen;
+ } else
+ return -EILSEQ;
+ break;
+ }
+
+ skb = bt_skb_alloc(len, GFP_ATOMIC);
+ if (!skb) {
+ BT_ERR("%s no memory for packet", hdev->name);
+ return -ENOMEM;
+ }
+
+ skb->dev = (void *) hdev;
+ bt_cb(skb)->pkt_type = type;
+
+ __reassembly(hdev, type) = skb;
+
+ scb = (void *) skb->cb;
+ scb->expect = len;
+ } else {
+ /* Continuation */
+
+ scb = (void *) skb->cb;
+ len = scb->expect;
+ }
+
+ len = min(len, count);
+
+ memcpy(skb_put(skb, len), data, len);
+
+ scb->expect -= len;
+
+ if (scb->expect == 0) {
+ /* Complete frame */
+
+ __reassembly(hdev, type) = NULL;
+
+ bt_cb(skb)->pkt_type = type;
+ hci_recv_frame(skb);
+ }
+
+ count -= len; data += len;
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL(hci_recv_fragment);
+
/* ---- Interface to upper protocols ---- */
/* Register/Unregister protocols.
@@ -1029,7 +1122,7 @@
skb = bt_skb_alloc(len, GFP_ATOMIC);
if (!skb) {
- BT_ERR("%s Can't allocate memory for HCI command", hdev->name);
+ BT_ERR("%s no memory for command", hdev->name);
return -ENOMEM;
}