kernel-fxtec-pro1x/include/net/bluetooth/rfcomm.h
Dean Jenkins 08c30aca9e Bluetooth: Remove RFCOMM session refcnt
Previous commits have improved the handling of the RFCOMM session
timer and the RFCOMM session pointers such that freed RFCOMM
session structures should no longer be erroneously accessed. The
RFCOMM session refcnt now has no purpose and will be deleted by
this commit.

Note that the RFCOMM session is now deleted as soon as the
RFCOMM control channel link is no longer required. This makes the
lifetime of the RFCOMM session deterministic and absolute.
Previously with the refcnt, there was uncertainty about when
the session structure would be deleted because the relative
refcnt prevented the session structure from being deleted at will.

It was noted that the refcnt could malfunction under very heavy
real-time processor loading in embedded SMP environments. This
could cause premature RFCOMM session deletion or double session
deletion that could result in kernel crashes. Removal of the
refcnt prevents this issue.

There are 4 connection / disconnection RFCOMM session scenarios:
host initiated control link ---> host disconnected control link
host initiated ctrl link ---> remote device disconnected ctrl link
remote device initiated ctrl link ---> host disconnected ctrl link
remote device initiated ctrl link ---> remote device disc'ed ctrl link

The control channel connection procedures are independent of the
disconnection procedures. Strangely, the RFCOMM session refcnt was
applying special treatment so erroneously combining connection and
disconnection events. This commit fixes this issue by removing
some session code that used the "initiator" member of the session
structure that was intended for use with the data channels.

Signed-off-by: Dean Jenkins <Dean_Jenkins@mentor.com>
Acked-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
2013-03-08 10:40:24 -03:00

366 lines
8.8 KiB
C

/*
RFCOMM implementation for Linux Bluetooth stack (BlueZ)
Copyright (C) 2002 Maxim Krasnyansky <maxk@qualcomm.com>
Copyright (C) 2002 Marcel Holtmann <marcel@holtmann.org>
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 __RFCOMM_H
#define __RFCOMM_H
#define RFCOMM_PSM 3
#define RFCOMM_CONN_TIMEOUT (HZ * 30)
#define RFCOMM_DISC_TIMEOUT (HZ * 20)
#define RFCOMM_AUTH_TIMEOUT (HZ * 25)
#define RFCOMM_IDLE_TIMEOUT (HZ * 2)
#define RFCOMM_DEFAULT_MTU 127
#define RFCOMM_DEFAULT_CREDITS 7
#define RFCOMM_MAX_L2CAP_MTU 1013
#define RFCOMM_MAX_CREDITS 40
#define RFCOMM_SKB_HEAD_RESERVE 8
#define RFCOMM_SKB_TAIL_RESERVE 2
#define RFCOMM_SKB_RESERVE (RFCOMM_SKB_HEAD_RESERVE + RFCOMM_SKB_TAIL_RESERVE)
#define RFCOMM_SABM 0x2f
#define RFCOMM_DISC 0x43
#define RFCOMM_UA 0x63
#define RFCOMM_DM 0x0f
#define RFCOMM_UIH 0xef
#define RFCOMM_TEST 0x08
#define RFCOMM_FCON 0x28
#define RFCOMM_FCOFF 0x18
#define RFCOMM_MSC 0x38
#define RFCOMM_RPN 0x24
#define RFCOMM_RLS 0x14
#define RFCOMM_PN 0x20
#define RFCOMM_NSC 0x04
#define RFCOMM_V24_FC 0x02
#define RFCOMM_V24_RTC 0x04
#define RFCOMM_V24_RTR 0x08
#define RFCOMM_V24_IC 0x40
#define RFCOMM_V24_DV 0x80
#define RFCOMM_RPN_BR_2400 0x0
#define RFCOMM_RPN_BR_4800 0x1
#define RFCOMM_RPN_BR_7200 0x2
#define RFCOMM_RPN_BR_9600 0x3
#define RFCOMM_RPN_BR_19200 0x4
#define RFCOMM_RPN_BR_38400 0x5
#define RFCOMM_RPN_BR_57600 0x6
#define RFCOMM_RPN_BR_115200 0x7
#define RFCOMM_RPN_BR_230400 0x8
#define RFCOMM_RPN_DATA_5 0x0
#define RFCOMM_RPN_DATA_6 0x1
#define RFCOMM_RPN_DATA_7 0x2
#define RFCOMM_RPN_DATA_8 0x3
#define RFCOMM_RPN_STOP_1 0
#define RFCOMM_RPN_STOP_15 1
#define RFCOMM_RPN_PARITY_NONE 0x0
#define RFCOMM_RPN_PARITY_ODD 0x1
#define RFCOMM_RPN_PARITY_EVEN 0x3
#define RFCOMM_RPN_PARITY_MARK 0x5
#define RFCOMM_RPN_PARITY_SPACE 0x7
#define RFCOMM_RPN_FLOW_NONE 0x00
#define RFCOMM_RPN_XON_CHAR 0x11
#define RFCOMM_RPN_XOFF_CHAR 0x13
#define RFCOMM_RPN_PM_BITRATE 0x0001
#define RFCOMM_RPN_PM_DATA 0x0002
#define RFCOMM_RPN_PM_STOP 0x0004
#define RFCOMM_RPN_PM_PARITY 0x0008
#define RFCOMM_RPN_PM_PARITY_TYPE 0x0010
#define RFCOMM_RPN_PM_XON 0x0020
#define RFCOMM_RPN_PM_XOFF 0x0040
#define RFCOMM_RPN_PM_FLOW 0x3F00
#define RFCOMM_RPN_PM_ALL 0x3F7F
struct rfcomm_hdr {
u8 addr;
u8 ctrl;
u8 len; /* Actual size can be 2 bytes */
} __packed;
struct rfcomm_cmd {
u8 addr;
u8 ctrl;
u8 len;
u8 fcs;
} __packed;
struct rfcomm_mcc {
u8 type;
u8 len;
} __packed;
struct rfcomm_pn {
u8 dlci;
u8 flow_ctrl;
u8 priority;
u8 ack_timer;
__le16 mtu;
u8 max_retrans;
u8 credits;
} __packed;
struct rfcomm_rpn {
u8 dlci;
u8 bit_rate;
u8 line_settings;
u8 flow_ctrl;
u8 xon_char;
u8 xoff_char;
__le16 param_mask;
} __packed;
struct rfcomm_rls {
u8 dlci;
u8 status;
} __packed;
struct rfcomm_msc {
u8 dlci;
u8 v24_sig;
} __packed;
/* ---- Core structures, flags etc ---- */
struct rfcomm_session {
struct list_head list;
struct socket *sock;
struct timer_list timer;
unsigned long state;
unsigned long flags;
int initiator;
/* Default DLC parameters */
int cfc;
uint mtu;
struct list_head dlcs;
};
struct rfcomm_dlc {
struct list_head list;
struct rfcomm_session *session;
struct sk_buff_head tx_queue;
struct timer_list timer;
spinlock_t lock;
unsigned long state;
unsigned long flags;
atomic_t refcnt;
u8 dlci;
u8 addr;
u8 priority;
u8 v24_sig;
u8 remote_v24_sig;
u8 mscex;
u8 out;
u8 sec_level;
u8 role_switch;
u32 defer_setup;
uint mtu;
uint cfc;
uint rx_credits;
uint tx_credits;
void *owner;
void (*data_ready)(struct rfcomm_dlc *d, struct sk_buff *skb);
void (*state_change)(struct rfcomm_dlc *d, int err);
void (*modem_status)(struct rfcomm_dlc *d, u8 v24_sig);
};
/* DLC and session flags */
#define RFCOMM_RX_THROTTLED 0
#define RFCOMM_TX_THROTTLED 1
#define RFCOMM_TIMED_OUT 2
#define RFCOMM_MSC_PENDING 3
#define RFCOMM_SEC_PENDING 4
#define RFCOMM_AUTH_PENDING 5
#define RFCOMM_AUTH_ACCEPT 6
#define RFCOMM_AUTH_REJECT 7
#define RFCOMM_DEFER_SETUP 8
#define RFCOMM_ENC_DROP 9
/* Scheduling flags and events */
#define RFCOMM_SCHED_WAKEUP 31
/* MSC exchange flags */
#define RFCOMM_MSCEX_TX 1
#define RFCOMM_MSCEX_RX 2
#define RFCOMM_MSCEX_OK (RFCOMM_MSCEX_TX + RFCOMM_MSCEX_RX)
/* CFC states */
#define RFCOMM_CFC_UNKNOWN -1
#define RFCOMM_CFC_DISABLED 0
#define RFCOMM_CFC_ENABLED RFCOMM_MAX_CREDITS
/* ---- RFCOMM SEND RPN ---- */
int rfcomm_send_rpn(struct rfcomm_session *s, int cr, u8 dlci,
u8 bit_rate, u8 data_bits, u8 stop_bits,
u8 parity, u8 flow_ctrl_settings,
u8 xon_char, u8 xoff_char, u16 param_mask);
/* ---- RFCOMM DLCs (channels) ---- */
struct rfcomm_dlc *rfcomm_dlc_alloc(gfp_t prio);
void rfcomm_dlc_free(struct rfcomm_dlc *d);
int rfcomm_dlc_open(struct rfcomm_dlc *d, bdaddr_t *src, bdaddr_t *dst,
u8 channel);
int rfcomm_dlc_close(struct rfcomm_dlc *d, int reason);
int rfcomm_dlc_send(struct rfcomm_dlc *d, struct sk_buff *skb);
int rfcomm_dlc_set_modem_status(struct rfcomm_dlc *d, u8 v24_sig);
int rfcomm_dlc_get_modem_status(struct rfcomm_dlc *d, u8 *v24_sig);
void rfcomm_dlc_accept(struct rfcomm_dlc *d);
#define rfcomm_dlc_lock(d) spin_lock(&d->lock)
#define rfcomm_dlc_unlock(d) spin_unlock(&d->lock)
static inline void rfcomm_dlc_hold(struct rfcomm_dlc *d)
{
atomic_inc(&d->refcnt);
}
static inline void rfcomm_dlc_put(struct rfcomm_dlc *d)
{
if (atomic_dec_and_test(&d->refcnt))
rfcomm_dlc_free(d);
}
extern void __rfcomm_dlc_throttle(struct rfcomm_dlc *d);
extern void __rfcomm_dlc_unthrottle(struct rfcomm_dlc *d);
static inline void rfcomm_dlc_throttle(struct rfcomm_dlc *d)
{
if (!test_and_set_bit(RFCOMM_RX_THROTTLED, &d->flags))
__rfcomm_dlc_throttle(d);
}
static inline void rfcomm_dlc_unthrottle(struct rfcomm_dlc *d)
{
if (test_and_clear_bit(RFCOMM_RX_THROTTLED, &d->flags))
__rfcomm_dlc_unthrottle(d);
}
/* ---- RFCOMM sessions ---- */
void rfcomm_session_getaddr(struct rfcomm_session *s, bdaddr_t *src,
bdaddr_t *dst);
/* ---- RFCOMM sockets ---- */
struct sockaddr_rc {
sa_family_t rc_family;
bdaddr_t rc_bdaddr;
u8 rc_channel;
};
#define RFCOMM_CONNINFO 0x02
struct rfcomm_conninfo {
__u16 hci_handle;
__u8 dev_class[3];
};
#define RFCOMM_LM 0x03
#define RFCOMM_LM_MASTER 0x0001
#define RFCOMM_LM_AUTH 0x0002
#define RFCOMM_LM_ENCRYPT 0x0004
#define RFCOMM_LM_TRUSTED 0x0008
#define RFCOMM_LM_RELIABLE 0x0010
#define RFCOMM_LM_SECURE 0x0020
#define rfcomm_pi(sk) ((struct rfcomm_pinfo *) sk)
struct rfcomm_pinfo {
struct bt_sock bt;
struct rfcomm_dlc *dlc;
u8 channel;
u8 sec_level;
u8 role_switch;
};
int rfcomm_init_sockets(void);
void rfcomm_cleanup_sockets(void);
int rfcomm_connect_ind(struct rfcomm_session *s, u8 channel,
struct rfcomm_dlc **d);
/* ---- RFCOMM TTY ---- */
#define RFCOMM_MAX_DEV 256
#define RFCOMMCREATEDEV _IOW('R', 200, int)
#define RFCOMMRELEASEDEV _IOW('R', 201, int)
#define RFCOMMGETDEVLIST _IOR('R', 210, int)
#define RFCOMMGETDEVINFO _IOR('R', 211, int)
#define RFCOMMSTEALDLC _IOW('R', 220, int)
#define RFCOMM_REUSE_DLC 0
#define RFCOMM_RELEASE_ONHUP 1
#define RFCOMM_HANGUP_NOW 2
#define RFCOMM_TTY_ATTACHED 3
#define RFCOMM_TTY_RELEASED 4
struct rfcomm_dev_req {
s16 dev_id;
u32 flags;
bdaddr_t src;
bdaddr_t dst;
u8 channel;
};
struct rfcomm_dev_info {
s16 id;
u32 flags;
u16 state;
bdaddr_t src;
bdaddr_t dst;
u8 channel;
};
struct rfcomm_dev_list_req {
u16 dev_num;
struct rfcomm_dev_info dev_info[0];
};
int rfcomm_dev_ioctl(struct sock *sk, unsigned int cmd, void __user *arg);
#ifdef CONFIG_BT_RFCOMM_TTY
int rfcomm_init_ttys(void);
void rfcomm_cleanup_ttys(void);
#else
static inline int rfcomm_init_ttys(void)
{
return 0;
}
static inline void rfcomm_cleanup_ttys(void)
{
}
#endif
#endif /* __RFCOMM_H */