Bluetooth: Ensure that HCI sysfs add/del is preempt safe

[mirror_ubuntu-bionic-kernel.git] / include / net / bluetooth / hci_core.h

/* 
   BlueZ - Bluetooth protocol stack for Linux
   Copyright (C) 2000-2001 Qualcomm Incorporated

   Written 2000,2001 by Maxim Krasnyansky <maxk@qualcomm.com>

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License version 2 as
   published by the Free Software Foundation;

   THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
   OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
   FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS.
   IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) AND AUTHOR(S) BE LIABLE FOR ANY
   CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES 
   WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 
   ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 
   OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

   ALL LIABILITY, INCLUDING LIABILITY FOR INFRINGEMENT OF ANY PATENTS, 
   COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS, RELATING TO USE OF THIS 
   SOFTWARE IS DISCLAIMED.
*/

#ifndef __HCI_CORE_H
#define __HCI_CORE_H

#include <net/bluetooth/hci.h>

/* HCI upper protocols */
#define HCI_PROTO_L2CAP	0
#define HCI_PROTO_SCO	1

/* HCI Core structures */
struct inquiry_data {
	bdaddr_t	bdaddr;
	__u8		pscan_rep_mode;
	__u8		pscan_period_mode;
	__u8		pscan_mode;
	__u8		dev_class[3];
	__le16		clock_offset;
	__s8		rssi;
	__u8		ssp_mode;
};

struct inquiry_entry {
	struct inquiry_entry 	*next;
	__u32			timestamp;
	struct inquiry_data	data;
};

struct inquiry_cache {
	spinlock_t 		lock;
	__u32			timestamp;
	struct inquiry_entry 	*list;
};

struct hci_conn_hash {
	struct list_head list;
	spinlock_t       lock;
	unsigned int     acl_num;
	unsigned int     sco_num;
};

struct hci_dev {
	struct list_head list;
	spinlock_t	lock;
	atomic_t	refcnt;

	char		name[8];
	unsigned long	flags;
	__u16		id;
	__u8		type;
	bdaddr_t	bdaddr;
	__u8		dev_name[248];
	__u8		dev_class[3];
	__u8		features[8];
	__u8		commands[64];
	__u8		ssp_mode;
	__u8		hci_ver;
	__u16		hci_rev;
	__u16		manufacturer;
	__u16		voice_setting;

	__u16		pkt_type;
	__u16		esco_type;
	__u16		link_policy;
	__u16		link_mode;

	__u32		idle_timeout;
	__u16		sniff_min_interval;
	__u16		sniff_max_interval;

	unsigned long	quirks;

	atomic_t	cmd_cnt;
	unsigned int	acl_cnt;
	unsigned int	sco_cnt;

	unsigned int	acl_mtu;
	unsigned int	sco_mtu;
	unsigned int	acl_pkts;
	unsigned int	sco_pkts;

	unsigned long	cmd_last_tx;
	unsigned long	acl_last_tx;
	unsigned long	sco_last_tx;

	struct tasklet_struct	cmd_task;
	struct tasklet_struct	rx_task;
	struct tasklet_struct	tx_task;

	struct sk_buff_head	rx_q;
	struct sk_buff_head	raw_q;
	struct sk_buff_head	cmd_q;

	struct sk_buff		*sent_cmd;
	struct sk_buff		*reassembly[3];

	struct semaphore	req_lock;
	wait_queue_head_t	req_wait_q;
	__u32			req_status;
	__u32			req_result;

	struct inquiry_cache	inq_cache;
	struct hci_conn_hash	conn_hash;

	struct hci_dev_stats	stat;

	struct sk_buff_head	driver_init;

	void			*driver_data;
	void			*core_data;

	atomic_t 		promisc;

	struct device		*parent;
	struct device		dev;

	struct module 		*owner;

	int (*open)(struct hci_dev *hdev);
	int (*close)(struct hci_dev *hdev);
	int (*flush)(struct hci_dev *hdev);
	int (*send)(struct sk_buff *skb);
	void (*destruct)(struct hci_dev *hdev);
	void (*notify)(struct hci_dev *hdev, unsigned int evt);
	int (*ioctl)(struct hci_dev *hdev, unsigned int cmd, unsigned long arg);
};

struct hci_conn {
	struct list_head list;

	atomic_t	 refcnt;
	spinlock_t	 lock;

	bdaddr_t	 dst;
	__u16		 handle;
	__u16		 state;
	__u8             mode;
	__u8		 type;
	__u8		 out;
	__u8		 attempt;
	__u8		 dev_class[3];
	__u8             features[8];
	__u8             ssp_mode;
	__u16            interval;
	__u16            pkt_type;
	__u16            link_policy;
	__u32		 link_mode;
	__u8             auth_type;
	__u8             sec_level;
	__u8             power_save;
	unsigned long	 pend;

	unsigned int	 sent;

	struct sk_buff_head data_q;

	struct timer_list disc_timer;
	struct timer_list idle_timer;

	struct work_struct work_add;
	struct work_struct work_del;

	struct device	dev;

	struct hci_dev	*hdev;
	void		*l2cap_data;
	void		*sco_data;
	void		*priv;

	struct hci_conn	*link;
};

extern struct hci_proto *hci_proto[];
extern struct list_head hci_dev_list;
extern struct list_head hci_cb_list;
extern rwlock_t hci_dev_list_lock;
extern rwlock_t hci_cb_list_lock;

/* ----- Inquiry cache ----- */
#define INQUIRY_CACHE_AGE_MAX   (HZ*30)   // 30 seconds
#define INQUIRY_ENTRY_AGE_MAX   (HZ*60)   // 60 seconds

#define inquiry_cache_lock(c)		spin_lock(&c->lock)
#define inquiry_cache_unlock(c)		spin_unlock(&c->lock)
#define inquiry_cache_lock_bh(c)	spin_lock_bh(&c->lock)
#define inquiry_cache_unlock_bh(c)	spin_unlock_bh(&c->lock)

static inline void inquiry_cache_init(struct hci_dev *hdev)
{
	struct inquiry_cache *c = &hdev->inq_cache;
	spin_lock_init(&c->lock);
	c->list = NULL;
}

static inline int inquiry_cache_empty(struct hci_dev *hdev)
{
	struct inquiry_cache *c = &hdev->inq_cache;
	return (c->list == NULL);
}

static inline long inquiry_cache_age(struct hci_dev *hdev)
{
	struct inquiry_cache *c = &hdev->inq_cache;
	return jiffies - c->timestamp;
}

static inline long inquiry_entry_age(struct inquiry_entry *e)
{
	return jiffies - e->timestamp;
}

struct inquiry_entry *hci_inquiry_cache_lookup(struct hci_dev *hdev, bdaddr_t *bdaddr);
void hci_inquiry_cache_update(struct hci_dev *hdev, struct inquiry_data *data);

/* ----- HCI Connections ----- */
enum {
	HCI_CONN_AUTH_PEND,
	HCI_CONN_ENCRYPT_PEND,
	HCI_CONN_RSWITCH_PEND,
	HCI_CONN_MODE_CHANGE_PEND,
};

static inline void hci_conn_hash_init(struct hci_dev *hdev)
{
	struct hci_conn_hash *h = &hdev->conn_hash;
	INIT_LIST_HEAD(&h->list);
	spin_lock_init(&h->lock);
	h->acl_num = 0;
	h->sco_num = 0;
}

static inline void hci_conn_hash_add(struct hci_dev *hdev, struct hci_conn *c)
{
	struct hci_conn_hash *h = &hdev->conn_hash;
	list_add(&c->list, &h->list);
	if (c->type == ACL_LINK)
		h->acl_num++;
	else
		h->sco_num++;
}

static inline void hci_conn_hash_del(struct hci_dev *hdev, struct hci_conn *c)
{
	struct hci_conn_hash *h = &hdev->conn_hash;
	list_del(&c->list);
	if (c->type == ACL_LINK)
		h->acl_num--;
	else
		h->sco_num--;
}

static inline struct hci_conn *hci_conn_hash_lookup_handle(struct hci_dev *hdev,
					__u16 handle)
{
	struct hci_conn_hash *h = &hdev->conn_hash;
	struct list_head *p;
	struct hci_conn  *c;

	list_for_each(p, &h->list) {
		c = list_entry(p, struct hci_conn, list);
		if (c->handle == handle)
			return c;
	}
	return NULL;
}

static inline struct hci_conn *hci_conn_hash_lookup_ba(struct hci_dev *hdev,
					__u8 type, bdaddr_t *ba)
{
	struct hci_conn_hash *h = &hdev->conn_hash;
	struct list_head *p;
	struct hci_conn  *c;

	list_for_each(p, &h->list) {
		c = list_entry(p, struct hci_conn, list);
		if (c->type == type && !bacmp(&c->dst, ba))
			return c;
	}
	return NULL;
}

static inline struct hci_conn *hci_conn_hash_lookup_state(struct hci_dev *hdev,
					__u8 type, __u16 state)
{
	struct hci_conn_hash *h = &hdev->conn_hash;
	struct list_head *p;
	struct hci_conn  *c;

	list_for_each(p, &h->list) {
		c = list_entry(p, struct hci_conn, list);
		if (c->type == type && c->state == state)
			return c;
	}
	return NULL;
}

void hci_acl_connect(struct hci_conn *conn);
void hci_acl_disconn(struct hci_conn *conn, __u8 reason);
void hci_add_sco(struct hci_conn *conn, __u16 handle);
void hci_setup_sync(struct hci_conn *conn, __u16 handle);

struct hci_conn *hci_conn_add(struct hci_dev *hdev, int type, bdaddr_t *dst);
int hci_conn_del(struct hci_conn *conn);
void hci_conn_hash_flush(struct hci_dev *hdev);
void hci_conn_check_pending(struct hci_dev *hdev);

struct hci_conn *hci_connect(struct hci_dev *hdev, int type, bdaddr_t *dst, __u8 sec_level, __u8 auth_type);
int hci_conn_check_link_mode(struct hci_conn *conn);
int hci_conn_security(struct hci_conn *conn, __u8 sec_level, __u8 auth_type);
int hci_conn_change_link_key(struct hci_conn *conn);
int hci_conn_switch_role(struct hci_conn *conn, __u8 role);

void hci_conn_enter_active_mode(struct hci_conn *conn);
void hci_conn_enter_sniff_mode(struct hci_conn *conn);

static inline void hci_conn_hold(struct hci_conn *conn)
{
	atomic_inc(&conn->refcnt);
	del_timer(&conn->disc_timer);
}

static inline void hci_conn_put(struct hci_conn *conn)
{
	if (atomic_dec_and_test(&conn->refcnt)) {
		unsigned long timeo;
		if (conn->type == ACL_LINK) {
			del_timer(&conn->idle_timer);
			if (conn->state == BT_CONNECTED) {
				timeo = msecs_to_jiffies(HCI_DISCONN_TIMEOUT);
				if (!conn->out)
					timeo *= 5;
			} else
				timeo = msecs_to_jiffies(10);
		} else
			timeo = msecs_to_jiffies(10);
		mod_timer(&conn->disc_timer, jiffies + timeo);
	}
}

/* ----- HCI tasks ----- */
static inline void hci_sched_cmd(struct hci_dev *hdev)
{
	tasklet_schedule(&hdev->cmd_task);
}

static inline void hci_sched_rx(struct hci_dev *hdev)
{
	tasklet_schedule(&hdev->rx_task);
}

static inline void hci_sched_tx(struct hci_dev *hdev)
{
	tasklet_schedule(&hdev->tx_task);
}

/* ----- HCI Devices ----- */
static inline void __hci_dev_put(struct hci_dev *d)
{
	if (atomic_dec_and_test(&d->refcnt))
		d->destruct(d);
}

static inline void hci_dev_put(struct hci_dev *d)
{ 
	__hci_dev_put(d);
	module_put(d->owner);
}

static inline struct hci_dev *__hci_dev_hold(struct hci_dev *d)
{
	atomic_inc(&d->refcnt);
	return d;
}

static inline struct hci_dev *hci_dev_hold(struct hci_dev *d)
{
	if (try_module_get(d->owner))
		return __hci_dev_hold(d);
	return NULL;
}

#define hci_dev_lock(d)		spin_lock(&d->lock)
#define hci_dev_unlock(d)	spin_unlock(&d->lock)
#define hci_dev_lock_bh(d)	spin_lock_bh(&d->lock)
#define hci_dev_unlock_bh(d)	spin_unlock_bh(&d->lock)

struct hci_dev *hci_dev_get(int index);
struct hci_dev *hci_get_route(bdaddr_t *src, bdaddr_t *dst);

struct hci_dev *hci_alloc_dev(void);
void hci_free_dev(struct hci_dev *hdev);
int hci_register_dev(struct hci_dev *hdev);
int hci_unregister_dev(struct hci_dev *hdev);
int hci_suspend_dev(struct hci_dev *hdev);
int hci_resume_dev(struct hci_dev *hdev);
int hci_dev_open(__u16 dev);
int hci_dev_close(__u16 dev);
int hci_dev_reset(__u16 dev);
int hci_dev_reset_stat(__u16 dev);
int hci_dev_cmd(unsigned int cmd, void __user *arg);
int hci_get_dev_list(void __user *arg);
int hci_get_dev_info(void __user *arg);
int hci_get_conn_list(void __user *arg);
int hci_get_conn_info(struct hci_dev *hdev, void __user *arg);
int hci_get_auth_info(struct hci_dev *hdev, void __user *arg);
int hci_inquiry(void __user *arg);

void hci_event_packet(struct hci_dev *hdev, struct sk_buff *skb);

/* Receive frame from HCI drivers */
static inline int hci_recv_frame(struct sk_buff *skb)
{
	struct hci_dev *hdev = (struct hci_dev *) skb->dev;
	if (!hdev || (!test_bit(HCI_UP, &hdev->flags) 
			&& !test_bit(HCI_INIT, &hdev->flags))) {
		kfree_skb(skb);
		return -ENXIO;
	}

	/* Incomming skb */
	bt_cb(skb)->incoming = 1;

	/* Time stamp */
	__net_timestamp(skb);

	/* Queue frame for rx task */
	skb_queue_tail(&hdev->rx_q, skb);
	hci_sched_rx(hdev);
	return 0;
}

int hci_recv_fragment(struct hci_dev *hdev, int type, void *data, int count);

int hci_register_sysfs(struct hci_dev *hdev);
void hci_unregister_sysfs(struct hci_dev *hdev);
void hci_conn_add_sysfs(struct hci_conn *conn);
void hci_conn_del_sysfs(struct hci_conn *conn);

#define SET_HCIDEV_DEV(hdev, pdev) ((hdev)->parent = (pdev))

/* ----- LMP capabilities ----- */
#define lmp_rswitch_capable(dev)   ((dev)->features[0] & LMP_RSWITCH)
#define lmp_encrypt_capable(dev)   ((dev)->features[0] & LMP_ENCRYPT)
#define lmp_sniff_capable(dev)     ((dev)->features[0] & LMP_SNIFF)
#define lmp_sniffsubr_capable(dev) ((dev)->features[5] & LMP_SNIFF_SUBR)
#define lmp_esco_capable(dev)      ((dev)->features[3] & LMP_ESCO)
#define lmp_ssp_capable(dev)       ((dev)->features[6] & LMP_SIMPLE_PAIR)

/* ----- HCI protocols ----- */
struct hci_proto {
	char		*name;
	unsigned int	id;
	unsigned long	flags;

	void		*priv;

	int (*connect_ind)	(struct hci_dev *hdev, bdaddr_t *bdaddr, __u8 type);
	int (*connect_cfm)	(struct hci_conn *conn, __u8 status);
	int (*disconn_ind)	(struct hci_conn *conn);
	int (*disconn_cfm)	(struct hci_conn *conn, __u8 reason);
	int (*recv_acldata)	(struct hci_conn *conn, struct sk_buff *skb, __u16 flags);
	int (*recv_scodata)	(struct hci_conn *conn, struct sk_buff *skb);
	int (*security_cfm)	(struct hci_conn *conn, __u8 status, __u8 encrypt);
};

static inline int hci_proto_connect_ind(struct hci_dev *hdev, bdaddr_t *bdaddr, __u8 type)
{
	register struct hci_proto *hp;
	int mask = 0;

	hp = hci_proto[HCI_PROTO_L2CAP];
	if (hp && hp->connect_ind)
		mask |= hp->connect_ind(hdev, bdaddr, type);

	hp = hci_proto[HCI_PROTO_SCO];
	if (hp && hp->connect_ind)
		mask |= hp->connect_ind(hdev, bdaddr, type);

	return mask;
}

static inline void hci_proto_connect_cfm(struct hci_conn *conn, __u8 status)
{
	register struct hci_proto *hp;

	hp = hci_proto[HCI_PROTO_L2CAP];
	if (hp && hp->connect_cfm)
		hp->connect_cfm(conn, status);

	hp = hci_proto[HCI_PROTO_SCO];
	if (hp && hp->connect_cfm)
		hp->connect_cfm(conn, status);
}

static inline int hci_proto_disconn_ind(struct hci_conn *conn)
{
	register struct hci_proto *hp;
	int reason = 0x13;

	hp = hci_proto[HCI_PROTO_L2CAP];
	if (hp && hp->disconn_ind)
		reason = hp->disconn_ind(conn);

	hp = hci_proto[HCI_PROTO_SCO];
	if (hp && hp->disconn_ind)
		reason = hp->disconn_ind(conn);

	return reason;
}

static inline void hci_proto_disconn_cfm(struct hci_conn *conn, __u8 reason)
{
	register struct hci_proto *hp;

	hp = hci_proto[HCI_PROTO_L2CAP];
	if (hp && hp->disconn_cfm)
		hp->disconn_cfm(conn, reason);

	hp = hci_proto[HCI_PROTO_SCO];
	if (hp && hp->disconn_cfm)
		hp->disconn_cfm(conn, reason);
}

static inline void hci_proto_auth_cfm(struct hci_conn *conn, __u8 status)
{
	register struct hci_proto *hp;
	__u8 encrypt;

	if (test_bit(HCI_CONN_ENCRYPT_PEND, &conn->pend))
		return;

	encrypt = (conn->link_mode & HCI_LM_ENCRYPT) ? 0x01 : 0x00;

	hp = hci_proto[HCI_PROTO_L2CAP];
	if (hp && hp->security_cfm)
		hp->security_cfm(conn, status, encrypt);

	hp = hci_proto[HCI_PROTO_SCO];
	if (hp && hp->security_cfm)
		hp->security_cfm(conn, status, encrypt);
}

static inline void hci_proto_encrypt_cfm(struct hci_conn *conn, __u8 status, __u8 encrypt)
{
	register struct hci_proto *hp;

	hp = hci_proto[HCI_PROTO_L2CAP];
	if (hp && hp->security_cfm)
		hp->security_cfm(conn, status, encrypt);

	hp = hci_proto[HCI_PROTO_SCO];
	if (hp && hp->security_cfm)
		hp->security_cfm(conn, status, encrypt);
}

int hci_register_proto(struct hci_proto *hproto);
int hci_unregister_proto(struct hci_proto *hproto);

/* ----- HCI callbacks ----- */
struct hci_cb {
	struct list_head list;

	char *name;

	void (*security_cfm)	(struct hci_conn *conn, __u8 status, __u8 encrypt);
	void (*key_change_cfm)	(struct hci_conn *conn, __u8 status);
	void (*role_switch_cfm)	(struct hci_conn *conn, __u8 status, __u8 role);
};

static inline void hci_auth_cfm(struct hci_conn *conn, __u8 status)
{
	struct list_head *p;
	__u8 encrypt;

	hci_proto_auth_cfm(conn, status);

	if (test_bit(HCI_CONN_ENCRYPT_PEND, &conn->pend))
		return;

	encrypt = (conn->link_mode & HCI_LM_ENCRYPT) ? 0x01 : 0x00;

	read_lock_bh(&hci_cb_list_lock);
	list_for_each(p, &hci_cb_list) {
		struct hci_cb *cb = list_entry(p, struct hci_cb, list);
		if (cb->security_cfm)
			cb->security_cfm(conn, status, encrypt);
	}
	read_unlock_bh(&hci_cb_list_lock);
}

static inline void hci_encrypt_cfm(struct hci_conn *conn, __u8 status, __u8 encrypt)
{
	struct list_head *p;

	if (conn->sec_level == BT_SECURITY_SDP)
		conn->sec_level = BT_SECURITY_LOW;

	hci_proto_encrypt_cfm(conn, status, encrypt);

	read_lock_bh(&hci_cb_list_lock);
	list_for_each(p, &hci_cb_list) {
		struct hci_cb *cb = list_entry(p, struct hci_cb, list);
		if (cb->security_cfm)
			cb->security_cfm(conn, status, encrypt);
	}
	read_unlock_bh(&hci_cb_list_lock);
}

static inline void hci_key_change_cfm(struct hci_conn *conn, __u8 status)
{
	struct list_head *p;

	read_lock_bh(&hci_cb_list_lock);
	list_for_each(p, &hci_cb_list) {
		struct hci_cb *cb = list_entry(p, struct hci_cb, list);
		if (cb->key_change_cfm)
			cb->key_change_cfm(conn, status);
	}
	read_unlock_bh(&hci_cb_list_lock);
}

static inline void hci_role_switch_cfm(struct hci_conn *conn, __u8 status, __u8 role)
{
	struct list_head *p;

	read_lock_bh(&hci_cb_list_lock);
	list_for_each(p, &hci_cb_list) {
		struct hci_cb *cb = list_entry(p, struct hci_cb, list);
		if (cb->role_switch_cfm)
			cb->role_switch_cfm(conn, status, role);
	}
	read_unlock_bh(&hci_cb_list_lock);
}

int hci_register_cb(struct hci_cb *hcb);
int hci_unregister_cb(struct hci_cb *hcb);

int hci_register_notifier(struct notifier_block *nb);
int hci_unregister_notifier(struct notifier_block *nb);

int hci_send_cmd(struct hci_dev *hdev, __u16 opcode, __u32 plen, void *param);
int hci_send_acl(struct hci_conn *conn, struct sk_buff *skb, __u16 flags);
int hci_send_sco(struct hci_conn *conn, struct sk_buff *skb);

void *hci_sent_cmd_data(struct hci_dev *hdev, __u16 opcode);

void hci_si_event(struct hci_dev *hdev, int type, int dlen, void *data);

/* ----- HCI Sockets ----- */
void hci_send_to_sock(struct hci_dev *hdev, struct sk_buff *skb);

/* HCI info for socket */
#define hci_pi(sk) ((struct hci_pinfo *) sk)

struct hci_pinfo {
	struct bt_sock    bt;
	struct hci_dev    *hdev;
	struct hci_filter filter;
	__u32             cmsg_mask;
};

/* HCI security filter */
#define HCI_SFLT_MAX_OGF  5

struct hci_sec_filter {
	__u32 type_mask;
	__u32 event_mask[2];
	__u32 ocf_mask[HCI_SFLT_MAX_OGF + 1][4];
};

/* ----- HCI requests ----- */
#define HCI_REQ_DONE	  0
#define HCI_REQ_PEND	  1
#define HCI_REQ_CANCELED  2

#define hci_req_lock(d)		down(&d->req_lock)
#define hci_req_unlock(d)	up(&d->req_lock)

void hci_req_complete(struct hci_dev *hdev, int result);

#endif /* __HCI_CORE_H */