hci_core.c

Linux嵌入式平台蓝牙协议栈软件

{
	struct hci_dev_list_req *dl;
	struct hci_dev_req *dr;
	struct list_head *p;
	int n = 0, size, err;
	__u16 dev_num;

	if (get_user(dev_num, (__u16 __user *) arg))
		return -EFAULT;

	if (!dev_num || dev_num > (PAGE_SIZE * 2) / sizeof(*dr))
		return -EINVAL;

	size = sizeof(*dl) + dev_num * sizeof(*dr);

	if (!(dl = kmalloc(size, GFP_KERNEL)))
		return -ENOMEM;

	dr = dl->dev_req;

	read_lock_bh(&hci_dev_list_lock);
	list_for_each(p, &hci_dev_list) {
		struct hci_dev *hdev;
		hdev = list_entry(p, struct hci_dev, list);
		(dr + n)->dev_id  = hdev->id;
		(dr + n)->dev_opt = hdev->flags;
		if (++n >= dev_num)
			break;
	}
	read_unlock_bh(&hci_dev_list_lock);

	dl->dev_num = n;
	size = sizeof(*dl) + n * sizeof(*dr);

	err = copy_to_user(arg, dl, size);
	kfree(dl);

	return err ? -EFAULT : 0;
}

int hci_get_dev_info(void __user *arg)
{
	struct hci_dev *hdev;
	struct hci_dev_info di;
	int err = 0;

	if (copy_from_user(&di, arg, sizeof(di)))
		return -EFAULT;

	if (!(hdev = hci_dev_get(di.dev_id)))
		return -ENODEV;

	strcpy(di.name, hdev->name);
	di.bdaddr   = hdev->bdaddr;
	di.type     = hdev->type;
	di.flags    = hdev->flags;
	di.pkt_type = hdev->pkt_type;
	di.acl_mtu  = hdev->acl_mtu;
	di.acl_pkts = hdev->acl_pkts;
	di.sco_mtu  = hdev->sco_mtu;
	di.sco_pkts = hdev->sco_pkts;
	di.link_policy = hdev->link_policy;
	di.link_mode   = hdev->link_mode;

	memcpy(&di.stat, &hdev->stat, sizeof(di.stat));
	memcpy(&di.features, &hdev->features, sizeof(di.features));

	if (copy_to_user(arg, &di, sizeof(di)))
		err = -EFAULT;

	hci_dev_put(hdev);

	return err;
}

/* ---- Interface to HCI drivers ---- */

/* Alloc HCI device */
struct hci_dev *hci_alloc_dev(void)
{
	struct hci_dev *hdev;

	hdev = kmalloc(sizeof(struct hci_dev), GFP_KERNEL);
	if (!hdev)
		return NULL;

	memset(hdev, 0, sizeof(struct hci_dev));

	return hdev;
}
EXPORT_SYMBOL(hci_alloc_dev);

/* Free HCI device */
void hci_free_dev(struct hci_dev *hdev)
{
	/* will free via class release */
	class_device_put(&hdev->class_dev);
}
EXPORT_SYMBOL(hci_free_dev);

/* Register HCI device */
int hci_register_dev(struct hci_dev *hdev)
{
	struct list_head *head = &hci_dev_list, *p;
	int id = 0;

	BT_DBG("%p name %s type %d owner %p", hdev, hdev->name, hdev->type, hdev->owner);

	if (!hdev->open || !hdev->close || !hdev->destruct)
		return -EINVAL;

	write_lock_bh(&hci_dev_list_lock);

	/* Find first available device id */
	list_for_each(p, &hci_dev_list) {
		if (list_entry(p, struct hci_dev, list)->id != id)
			break;
		head = p; id++;
	}
	
	sprintf(hdev->name, "hci%d", id);
	hdev->id = id;
	list_add(&hdev->list, head);

	atomic_set(&hdev->refcnt, 1);
	spin_lock_init(&hdev->lock);

	hdev->flags = 0;
	hdev->pkt_type  = (HCI_DM1 | HCI_DH1 | HCI_HV1);
	hdev->link_mode = (HCI_LM_ACCEPT);

	tasklet_init(&hdev->cmd_task, hci_cmd_task,(unsigned long) hdev);
	tasklet_init(&hdev->rx_task, hci_rx_task, (unsigned long) hdev);
	tasklet_init(&hdev->tx_task, hci_tx_task, (unsigned long) hdev);

	skb_queue_head_init(&hdev->rx_q);
	skb_queue_head_init(&hdev->cmd_q);
	skb_queue_head_init(&hdev->raw_q);

	init_waitqueue_head(&hdev->req_wait_q);
	init_MUTEX(&hdev->req_lock);

	inquiry_cache_init(hdev);

	hci_conn_hash_init(hdev);

	memset(&hdev->stat, 0, sizeof(struct hci_dev_stats));

	atomic_set(&hdev->promisc, 0);

	write_unlock_bh(&hci_dev_list_lock);

	hci_register_sysfs(hdev);

	hci_notify(hdev, HCI_DEV_REG);

	return id;
}
EXPORT_SYMBOL(hci_register_dev);

/* Unregister HCI device */
int hci_unregister_dev(struct hci_dev *hdev)
{
	BT_DBG("%p name %s type %d", hdev, hdev->name, hdev->type);

	hci_unregister_sysfs(hdev);

	write_lock_bh(&hci_dev_list_lock);
	list_del(&hdev->list);
	write_unlock_bh(&hci_dev_list_lock);

	hci_dev_do_close(hdev);

	hci_notify(hdev, HCI_DEV_UNREG);

	__hci_dev_put(hdev);
	return 0;
}
EXPORT_SYMBOL(hci_unregister_dev);

/* Suspend HCI device */
int hci_suspend_dev(struct hci_dev *hdev)
{
	hci_notify(hdev, HCI_DEV_SUSPEND);
	return 0;
}
EXPORT_SYMBOL(hci_suspend_dev);

/* Resume HCI device */
int hci_resume_dev(struct hci_dev *hdev)
{
	hci_notify(hdev, HCI_DEV_RESUME);
	return 0;
}
EXPORT_SYMBOL(hci_resume_dev);

/* ---- Interface to upper protocols ---- */

/* Register/Unregister protocols.
 * hci_task_lock is used to ensure that no tasks are running. */
int hci_register_proto(struct hci_proto *hp)
{
	int err = 0;

	BT_DBG("%p name %s id %d", hp, hp->name, hp->id);

	if (hp->id >= HCI_MAX_PROTO)
		return -EINVAL;

	write_lock_bh(&hci_task_lock);

	if (!hci_proto[hp->id])
		hci_proto[hp->id] = hp;
	else
		err = -EEXIST;

	write_unlock_bh(&hci_task_lock);

	return err;
}
EXPORT_SYMBOL(hci_register_proto);

int hci_unregister_proto(struct hci_proto *hp)
{
	int err = 0;

	BT_DBG("%p name %s id %d", hp, hp->name, hp->id);

	if (hp->id >= HCI_MAX_PROTO)
		return -EINVAL;

	write_lock_bh(&hci_task_lock);

	if (hci_proto[hp->id])
		hci_proto[hp->id] = NULL;
	else
		err = -ENOENT;

	write_unlock_bh(&hci_task_lock);

	return err;
}
EXPORT_SYMBOL(hci_unregister_proto);

static int hci_send_frame(struct sk_buff *skb)
{
	struct hci_dev *hdev = (struct hci_dev *) skb->dev;

	if (!hdev) {
		kfree_skb(skb);
		return -ENODEV;
	}

	BT_DBG("%s type %d len %d", hdev->name, skb->pkt_type, skb->len);

	if (atomic_read(&hdev->promisc)) {
		/* Time stamp */
		do_gettimeofday(&skb->stamp);

		hci_send_to_sock(hdev, skb);
	}

	/* Get rid of skb owner, prior to sending to the driver. */
	skb_orphan(skb);

	return hdev->send(skb);
}

/* Send HCI command */
int hci_send_cmd(struct hci_dev *hdev, __u16 ogf, __u16 ocf, __u32 plen, void *param)
{
	int len = HCI_COMMAND_HDR_SIZE + plen;
	struct hci_command_hdr *hdr;
	struct sk_buff *skb;

	BT_DBG("%s ogf 0x%x ocf 0x%x plen %d", hdev->name, ogf, ocf, plen);

	skb = bt_skb_alloc(len, GFP_ATOMIC);
	if (!skb) {
		BT_ERR("%s Can't allocate memory for HCI command", hdev->name);
		return -ENOMEM;
	}

	hdr = (struct hci_command_hdr *) skb_put(skb, HCI_COMMAND_HDR_SIZE);
	hdr->opcode = __cpu_to_le16(hci_opcode_pack(ogf, ocf));
	hdr->plen   = plen;

	if (plen)
		memcpy(skb_put(skb, plen), param, plen);

	BT_DBG("skb len %d", skb->len);

	skb->pkt_type = HCI_COMMAND_PKT;
	skb->dev = (void *) hdev;
	skb_queue_tail(&hdev->cmd_q, skb);
	hci_sched_cmd(hdev);

	return 0;
}
EXPORT_SYMBOL(hci_send_cmd);

/* Get data from the previously sent command */
void *hci_sent_cmd_data(struct hci_dev *hdev, __u16 ogf, __u16 ocf)
{
	struct hci_command_hdr *hdr;

	if (!hdev->sent_cmd)
		return NULL;

	hdr = (void *) hdev->sent_cmd->data;

	if (hdr->opcode != __cpu_to_le16(hci_opcode_pack(ogf, ocf)))
		return NULL;

	BT_DBG("%s ogf 0x%x ocf 0x%x", hdev->name, ogf, ocf);

	return hdev->sent_cmd->data + HCI_COMMAND_HDR_SIZE;
}

/* Send ACL data */
static void hci_add_acl_hdr(struct sk_buff *skb, __u16 handle, __u16 flags)
{
	struct hci_acl_hdr *hdr;
	int len = skb->len;

	hdr = (struct hci_acl_hdr *) skb_push(skb, HCI_ACL_HDR_SIZE);
	hdr->handle = __cpu_to_le16(hci_handle_pack(handle, flags));
	hdr->dlen   = __cpu_to_le16(len);

	skb->h.raw = (void *) hdr;
}

int hci_send_acl(struct hci_conn *conn, struct sk_buff *skb, __u16 flags)
{
	struct hci_dev *hdev = conn->hdev;
	struct sk_buff *list;

	BT_DBG("%s conn %p flags 0x%x", hdev->name, conn, flags);

	skb->dev = (void *) hdev;
	skb->pkt_type = HCI_ACLDATA_PKT;
	hci_add_acl_hdr(skb, conn->handle, flags | ACL_START);

	if (!(list = skb_shinfo(skb)->frag_list)) {
		/* Non fragmented */
		BT_DBG("%s nonfrag skb %p len %d", hdev->name, skb, skb->len);

		skb_queue_tail(&conn->data_q, skb);
	} else {
		/* Fragmented */
		BT_DBG("%s frag %p len %d", hdev->name, skb, skb->len);

		skb_shinfo(skb)->frag_list = NULL;

		/* Queue all fragments atomically */
		spin_lock_bh(&conn->data_q.lock);

		__skb_queue_tail(&conn->data_q, skb);
		do {
			skb = list; list = list->next;
			
			skb->dev = (void *) hdev;
			skb->pkt_type = HCI_ACLDATA_PKT;
			hci_add_acl_hdr(skb, conn->handle, flags | ACL_CONT);

			BT_DBG("%s frag %p len %d", hdev->name, skb, skb->len);

			__skb_queue_tail(&conn->data_q, skb);
		} while (list);

		spin_unlock_bh(&conn->data_q.lock);
	}

	hci_sched_tx(hdev);
	return 0;
}
EXPORT_SYMBOL(hci_send_acl);

/* Send SCO data */
int hci_send_sco(struct hci_conn *conn, struct sk_buff *skb)
{
	struct hci_dev *hdev = conn->hdev;
	struct hci_sco_hdr hdr;

	BT_DBG("%s len %d", hdev->name, skb->len);

	if (skb->len > hdev->sco_mtu) {
		kfree_skb(skb);
		return -EINVAL;
	}

	hdr.handle = __cpu_to_le16(conn->handle);
	hdr.dlen   = skb->len;

	skb->h.raw = skb_push(skb, HCI_SCO_HDR_SIZE);
	memcpy(skb->h.raw, &hdr, HCI_SCO_HDR_SIZE);

	skb->dev = (void *) hdev;
	skb->pkt_type = HCI_SCODATA_PKT;
	skb_queue_tail(&conn->data_q, skb);
	hci_sched_tx(hdev);
	return 0;
}
EXPORT_SYMBOL(hci_send_sco);

/* ---- HCI TX task (outgoing data) ---- */

/* HCI Connection scheduler */
static inline struct hci_conn *hci_low_sent(struct hci_dev *hdev, __u8 type, int *quote)
{
	struct hci_conn_hash *h = &hdev->conn_hash;
	struct hci_conn  *conn = NULL;
	int num = 0, min = ~0;
	struct list_head *p;

	/* We don't have to lock device here. Connections are always 
	 * added and removed with TX task disabled. */
	list_for_each(p, &h->list) {
		struct hci_conn *c;
		c = list_entry(p, struct hci_conn, list);

		if (c->type != type || c->state != BT_CONNECTED
				|| skb_queue_empty(&c->data_q))
			continue;
		num++;

		if (c->sent < min) {
			min  = c->sent;
			conn = c;
		}
	}

	if (conn) {
		int cnt = (type == ACL_LINK ? hdev->acl_cnt : hdev->sco_cnt);
		int q = cnt / num;
		*quote = q ? q : 1;
	} else
		*quote = 0;

	BT_DBG("conn %p quote %d", conn, *quote);
	return conn;
}

static inline void hci_acl_tx_to(struct hci_dev *hdev)
{
	struct hci_conn_hash *h = &hdev->conn_hash;
	struct list_head *p;
	struct hci_conn  *c;

	BT_ERR("%s ACL tx timeout", hdev->name);

	/* Kill stalled connections */
	list_for_each(p, &h->list) {
		c = list_entry(p, struct hci_conn, list);
		if (c->type == ACL_LINK && c->sent) {
			BT_ERR("%s killing stalled ACL connection %s",
				hdev->name, batostr(&c->dst));
			hci_acl_disconn(c, 0x13);
		}
	}
}

static inline void hci_sched_acl(struct hci_dev *hdev)
{
	struct hci_conn *conn;
	struct sk_buff *skb;
	int quote;

	BT_DBG("%s", hdev->name);

	/* ACL tx timeout must be longer than maximum
	 * link supervision timeout (40.9 seconds) */
	if (!hdev->acl_cnt && (jiffies - hdev->acl_last_tx) > (HZ * 45))
		hci_acl_tx_to(hdev);

	while (hdev->acl_cnt && (conn = hci_low_sent(hdev, ACL_LINK, &quote))) {
		while (quote-- && (skb = skb_dequeue(&conn->data_q))) {
			BT_DBG("skb %p len %d", skb, skb->len);
			hci_send_frame(skb);
			hdev->acl_last_tx = jiffies;

			hdev->acl_cnt--;
			conn->sent++;
		}
	}
}

/* Schedule SCO */
static inline void hci_sched_sco(struct hci_dev *hdev)
{
	struct hci_conn *conn;
	struct sk_buff *skb;
	int quote;

	BT_DBG("%s", hdev->name);

	while (hdev->sco_cnt && (conn = hci_low_sent(hdev, SCO_LINK, &quote))) {
		while (quote-- && (skb = skb_dequeue(&conn->data_q))) {
			BT_DBG("skb %p len %d", skb, skb->len);
			hci_send_frame(skb);

			conn->sent++;
			if (conn->sent == ~0)
				conn->sent = 0;
		}
	}
}

static void hci_tx_task(unsigned long arg)
{
	struct hci_dev *hdev = (struct hci_dev *) arg;
	struct sk_buff *skb;

	read_lock(&hci_task_lock);

	BT_DBG("%s acl %d sco %d", hdev->name, hdev->acl_cnt, hdev->sco_cnt);

	/* Schedule queues and send stuff to HCI driver */

	hci_sched_acl(hdev);

	hci_sched_sco(hdev);

	/* Send next queued raw (unknown type) packet */
	while ((skb = skb_dequeue(&hdev->raw_q)))
		hci_send_frame(skb);

	read_unlock(&hci_task_lock);
}

/* ----- HCI RX task (incoming data proccessing) ----- */

/* ACL data packet */
static inline void hci_acldata_packet(struct hci_dev *hdev, struct sk_buff *skb)
{
	struct hci_acl_hdr *hdr = (void *) skb->data;
	struct hci_conn *conn;
	__u16 handle, flags;

	skb_pull(skb, HCI_ACL_HDR_SIZE);

	handle = __le16_to_cpu(hdr->handle);
	flags  = hci_flags(handle);
	handle = hci_handle(handle);

	BT_DBG("%s len %d handle 0x%x flags 0x%x", hdev->name, skb->len, handle, flags);

	hdev->stat.acl_rx++;

	hci_dev_lock(hdev);
	conn = hci_conn_hash_lookup_handle(hdev, handle);
	hci_dev_unlock(hdev);
	
	if (conn) {
		register struct hci_proto *hp;

		/* Send to upper protocol */
		if ((hp = hci_proto[HCI_PROTO_L2CAP]) && hp->recv_acldata) {
			hp->recv_acldata(conn, skb, flags);
			return;
		}
	} else {
		BT_ERR("%s ACL packet for unknown connection handle %d", 
			hdev->name, handle);
	}

	kfree_skb(skb);
}

/* SCO data packet */
static inline void hci_scodata_packet(struct hci_dev *hdev, struct sk_buff *skb)
{
	struct hci_sco_hdr *hdr = (void *) skb->data;
	struct hci_conn *conn;
	__u16 handle;

	skb_pull(skb, HCI_SCO_HDR_SIZE);

	handle = __le16_to_cpu(hdr->handle);

	BT_DBG("%s len %d handle 0x%x", hdev->name, skb->len, handle);

	hdev->stat.sco_rx++;

	hci_dev_lock(hdev);
	conn = hci_conn_hash_lookup_handle(hdev, handle);
	hci_dev_unlock(hdev);

	if (conn) {
		register struct hci_proto *hp;

		/* Send to upper protocol */
		if ((hp = hci_proto[HCI_PROTO_SCO]) && hp->recv_scodata) {
			hp->recv_scodata(conn, skb);
			return;
		}
	} else {
		BT_ERR("%s SCO packet for unknown connection handle %d", 
			hdev->name, handle);
	}

	kfree_skb(skb);
}

void hci_rx_task(unsigned long arg)
{
	struct hci_dev *hdev = (struct hci_dev *) arg;
	struct sk_buff *skb;

	BT_DBG("%s", hdev->name);

	read_lock(&hci_task_lock);

	while ((skb = skb_dequeue(&hdev->rx_q))) {
		if (atomic_read(&hdev->promisc)) {
			/* Send copy to the sockets */
			hci_send_to_sock(hdev, skb);
		}

		if (test_bit(HCI_RAW, &hdev->flags)) {
			kfree_skb(skb);
			continue;
		}

		if (test_bit(HCI_INIT, &hdev->flags)) {
			/* Don't process data packets in this states. */
			switch (skb->pkt_type) {
			case HCI_ACLDATA_PKT:
			case HCI_SCODATA_PKT:
				kfree_skb(skb);
				continue;
			};
		}

		/* Process frame */
		switch (skb->pkt_type) {
		case HCI_EVENT_PKT:
			hci_event_packet(hdev, skb);
			break;

		case HCI_ACLDATA_PKT:
			BT_DBG("%s ACL data packet", hdev->name);
			hci_acldata_packet(hdev, skb);
			break;

		case HCI_SCODATA_PKT:
			BT_DBG("%s SCO data packet", hdev->name);
			hci_scodata_packet(hdev, skb);
			break;

		default:
			kfree_skb(skb);
			break;
		}
	}

	read_unlock(&hci_task_lock);
}

static void hci_cmd_task(unsigned long arg)
{
	struct hci_dev *hdev = (struct hci_dev *) arg;
	struct sk_buff *skb;

	BT_DBG("%s cmd %d", hdev->name, atomic_read(&hdev->cmd_cnt));

	if (!atomic_read(&hdev->cmd_cnt) && (jiffies - hdev->cmd_last_tx) > HZ) {
		BT_ERR("%s command tx timeout", hdev->name);
		atomic_set(&hdev->cmd_cnt, 1);
	}

	/* Send queued commands */
	if (atomic_read(&hdev->cmd_cnt) && (skb = skb_dequeue(&hdev->cmd_q))) {
		if (hdev->sent_cmd)
			kfree_skb(hdev->sent_cmd);

		if ((hdev->sent_cmd = skb_clone(skb, GFP_ATOMIC))) {
			atomic_dec(&hdev->cmd_cnt);
			hci_send_frame(skb);
			hdev->cmd_last_tx = jiffies;
		} else {
			skb_queue_head(&hdev->cmd_q, skb);
			hci_sched_cmd(hdev);
		}
	}
}