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path: root/drivers/tty/n_gsm.c
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Diffstat (limited to 'drivers/tty/n_gsm.c')
-rw-r--r--drivers/tty/n_gsm.c367
1 files changed, 231 insertions, 136 deletions
diff --git a/drivers/tty/n_gsm.c b/drivers/tty/n_gsm.c
index fc7bbba585c..2ebe47b78a3 100644
--- a/drivers/tty/n_gsm.c
+++ b/drivers/tty/n_gsm.c
@@ -108,7 +108,7 @@ struct gsm_mux_net {
*/
struct gsm_msg {
- struct gsm_msg *next;
+ struct list_head list;
u8 addr; /* DLCI address + flags */
u8 ctrl; /* Control byte + flags */
unsigned int len; /* Length of data block (can be zero) */
@@ -134,7 +134,6 @@ struct gsm_dlci {
#define DLCI_OPENING 1 /* Sending SABM not seen UA */
#define DLCI_OPEN 2 /* SABM/UA complete */
#define DLCI_CLOSING 3 /* Sending DISC not seen UA/DM */
- struct kref ref; /* freed from port or mux close */
struct mutex mutex;
/* Link layer */
@@ -195,6 +194,7 @@ struct gsm_control {
struct gsm_mux {
struct tty_struct *tty; /* The tty our ldisc is bound to */
spinlock_t lock;
+ struct mutex mutex;
unsigned int num;
struct kref ref;
@@ -245,8 +245,7 @@ struct gsm_mux {
unsigned int tx_bytes; /* TX data outstanding */
#define TX_THRESH_HI 8192
#define TX_THRESH_LO 2048
- struct gsm_msg *tx_head; /* Pending data packets */
- struct gsm_msg *tx_tail;
+ struct list_head tx_list; /* Pending data packets */
/* Control messages */
struct timer_list t2_timer; /* Retransmit timer for commands */
@@ -489,7 +488,7 @@ static void gsm_print_packet(const char *hdr, int addr, int cr,
default:
if (!(control & 0x01)) {
pr_cont("I N(S)%d N(R)%d",
- (control & 0x0E) >> 1, (control & 0xE) >> 5);
+ (control & 0x0E) >> 1, (control & 0xE0) >> 5);
} else switch (control & 0x0F) {
case RR:
pr_cont("RR(%d)", (control & 0xE0) >> 5);
@@ -663,7 +662,7 @@ static struct gsm_msg *gsm_data_alloc(struct gsm_mux *gsm, u8 addr, int len,
m->len = len;
m->addr = addr;
m->ctrl = ctrl;
- m->next = NULL;
+ INIT_LIST_HEAD(&m->list);
return m;
}
@@ -673,22 +672,21 @@ static struct gsm_msg *gsm_data_alloc(struct gsm_mux *gsm, u8 addr, int len,
*
* The tty device has called us to indicate that room has appeared in
* the transmit queue. Ram more data into the pipe if we have any
+ * If we have been flow-stopped by a CMD_FCOFF, then we can only
+ * send messages on DLCI0 until CMD_FCON
*
* FIXME: lock against link layer control transmissions
*/
static void gsm_data_kick(struct gsm_mux *gsm)
{
- struct gsm_msg *msg = gsm->tx_head;
+ struct gsm_msg *msg, *nmsg;
int len;
int skip_sof = 0;
- /* FIXME: We need to apply this solely to data messages */
- if (gsm->constipated)
- return;
-
- while (gsm->tx_head != NULL) {
- msg = gsm->tx_head;
+ list_for_each_entry_safe(msg, nmsg, &gsm->tx_list, list) {
+ if (gsm->constipated && msg->addr)
+ continue;
if (gsm->encoding != 0) {
gsm->txframe[0] = GSM1_SOF;
len = gsm_stuff_frame(msg->data,
@@ -711,14 +709,13 @@ static void gsm_data_kick(struct gsm_mux *gsm)
len - skip_sof) < 0)
break;
/* FIXME: Can eliminate one SOF in many more cases */
- gsm->tx_head = msg->next;
- if (gsm->tx_head == NULL)
- gsm->tx_tail = NULL;
gsm->tx_bytes -= msg->len;
- kfree(msg);
/* For a burst of frames skip the extra SOF within the
burst */
skip_sof = 1;
+
+ list_del(&msg->list);
+ kfree(msg);
}
}
@@ -768,11 +765,7 @@ static void __gsm_data_queue(struct gsm_dlci *dlci, struct gsm_msg *msg)
msg->data = dp;
/* Add to the actual output queue */
- if (gsm->tx_tail)
- gsm->tx_tail->next = msg;
- else
- gsm->tx_head = msg;
- gsm->tx_tail = msg;
+ list_add_tail(&msg->list, &gsm->tx_list);
gsm->tx_bytes += msg->len;
gsm_data_kick(gsm);
}
@@ -815,7 +808,7 @@ static int gsm_dlci_data_output(struct gsm_mux *gsm, struct gsm_dlci *dlci)
int h = dlci->adaption - 1;
total_size = 0;
- while(1) {
+ while (1) {
len = kfifo_len(dlci->fifo);
if (len == 0)
return total_size;
@@ -835,8 +828,8 @@ static int gsm_dlci_data_output(struct gsm_mux *gsm, struct gsm_dlci *dlci)
switch (dlci->adaption) {
case 1: /* Unstructured */
break;
- case 2: /* Unstructed with modem bits. Always one byte as we never
- send inline break data */
+ case 2: /* Unstructed with modem bits.
+ Always one byte as we never send inline break data */
*dp++ = gsm_encode_modem(dlci);
break;
}
@@ -875,7 +868,7 @@ static int gsm_dlci_data_output_framed(struct gsm_mux *gsm,
/* dlci->skb is locked by tx_lock */
if (dlci->skb == NULL) {
- dlci->skb = skb_dequeue(&dlci->skb_list);
+ dlci->skb = skb_dequeue_tail(&dlci->skb_list);
if (dlci->skb == NULL)
return 0;
first = 1;
@@ -886,7 +879,7 @@ static int gsm_dlci_data_output_framed(struct gsm_mux *gsm,
if (len > gsm->mtu) {
if (dlci->adaption == 3) {
/* Over long frame, bin it */
- kfree_skb(dlci->skb);
+ dev_kfree_skb_any(dlci->skb);
dlci->skb = NULL;
return 0;
}
@@ -899,8 +892,11 @@ static int gsm_dlci_data_output_framed(struct gsm_mux *gsm,
/* FIXME: need a timer or something to kick this so it can't
get stuck with no work outstanding and no buffer free */
- if (msg == NULL)
+ if (msg == NULL) {
+ skb_queue_tail(&dlci->skb_list, dlci->skb);
+ dlci->skb = NULL;
return -ENOMEM;
+ }
dp = msg->data;
if (dlci->adaption == 4) { /* Interruptible framed (Packetised Data) */
@@ -912,7 +908,7 @@ static int gsm_dlci_data_output_framed(struct gsm_mux *gsm,
skb_pull(dlci->skb, len);
__gsm_data_queue(dlci, msg);
if (last) {
- kfree_skb(dlci->skb);
+ dev_kfree_skb_any(dlci->skb);
dlci->skb = NULL;
}
return size;
@@ -971,15 +967,21 @@ static void gsm_dlci_data_sweep(struct gsm_mux *gsm)
static void gsm_dlci_data_kick(struct gsm_dlci *dlci)
{
unsigned long flags;
+ int sweep;
+
+ if (dlci->constipated)
+ return;
spin_lock_irqsave(&dlci->gsm->tx_lock, flags);
/* If we have nothing running then we need to fire up */
+ sweep = (dlci->gsm->tx_bytes < TX_THRESH_LO);
if (dlci->gsm->tx_bytes == 0) {
if (dlci->net)
gsm_dlci_data_output_framed(dlci->gsm, dlci);
else
gsm_dlci_data_output(dlci->gsm, dlci);
- } else if (dlci->gsm->tx_bytes < TX_THRESH_LO)
+ }
+ if (sweep)
gsm_dlci_data_sweep(dlci->gsm);
spin_unlock_irqrestore(&dlci->gsm->tx_lock, flags);
}
@@ -1027,6 +1029,7 @@ static void gsm_process_modem(struct tty_struct *tty, struct gsm_dlci *dlci,
{
int mlines = 0;
u8 brk = 0;
+ int fc;
/* The modem status command can either contain one octet (v.24 signals)
or two octets (v.24 signals + break signals). The length field will
@@ -1038,19 +1041,21 @@ static void gsm_process_modem(struct tty_struct *tty, struct gsm_dlci *dlci,
else {
brk = modem & 0x7f;
modem = (modem >> 7) & 0x7f;
- };
+ }
/* Flow control/ready to communicate */
- if (modem & MDM_FC) {
+ fc = (modem & MDM_FC) || !(modem & MDM_RTR);
+ if (fc && !dlci->constipated) {
/* Need to throttle our output on this device */
dlci->constipated = 1;
- }
- if (modem & MDM_RTC) {
- mlines |= TIOCM_DSR | TIOCM_DTR;
+ } else if (!fc && dlci->constipated) {
dlci->constipated = 0;
gsm_dlci_data_kick(dlci);
}
+
/* Map modem bits */
+ if (modem & MDM_RTC)
+ mlines |= TIOCM_DSR | TIOCM_DTR;
if (modem & MDM_RTR)
mlines |= TIOCM_RTS | TIOCM_CTS;
if (modem & MDM_IC)
@@ -1061,11 +1066,11 @@ static void gsm_process_modem(struct tty_struct *tty, struct gsm_dlci *dlci,
/* Carrier drop -> hangup */
if (tty) {
if ((mlines & TIOCM_CD) == 0 && (dlci->modem_rx & TIOCM_CD))
- if (!(tty->termios->c_cflag & CLOCAL))
+ if (!(tty->termios.c_cflag & CLOCAL))
tty_hangup(tty);
- if (brk & 0x01)
- tty_insert_flip_char(tty, 0, TTY_BREAK);
}
+ if (brk & 0x01)
+ tty_insert_flip_char(&dlci->port, 0, TTY_BREAK);
dlci->modem_rx = mlines;
}
@@ -1085,6 +1090,7 @@ static void gsm_control_modem(struct gsm_mux *gsm, u8 *data, int clen)
{
unsigned int addr = 0;
unsigned int modem = 0;
+ unsigned int brk = 0;
struct gsm_dlci *dlci;
int len = clen;
u8 *dp = data;
@@ -1111,6 +1117,16 @@ static void gsm_control_modem(struct gsm_mux *gsm, u8 *data, int clen)
if (len == 0)
return;
}
+ len--;
+ if (len > 0) {
+ while (gsm_read_ea(&brk, *dp++) == 0) {
+ len--;
+ if (len == 0)
+ return;
+ }
+ modem <<= 7;
+ modem |= (brk & 0x7f);
+ }
tty = tty_port_tty_get(&dlci->port);
gsm_process_modem(tty, dlci, modem, clen);
if (tty) {
@@ -1133,8 +1149,8 @@ static void gsm_control_modem(struct gsm_mux *gsm, u8 *data, int clen)
static void gsm_control_rls(struct gsm_mux *gsm, u8 *data, int clen)
{
- struct tty_struct *tty;
- unsigned int addr = 0 ;
+ struct tty_port *port;
+ unsigned int addr = 0;
u8 bits;
int len = clen;
u8 *dp = data;
@@ -1156,19 +1172,18 @@ static void gsm_control_rls(struct gsm_mux *gsm, u8 *data, int clen)
bits = *dp;
if ((bits & 1) == 0)
return;
- /* See if we have an uplink tty */
- tty = tty_port_tty_get(&gsm->dlci[addr]->port);
- if (tty) {
- if (bits & 2)
- tty_insert_flip_char(tty, 0, TTY_OVERRUN);
- if (bits & 4)
- tty_insert_flip_char(tty, 0, TTY_PARITY);
- if (bits & 8)
- tty_insert_flip_char(tty, 0, TTY_FRAME);
- tty_flip_buffer_push(tty);
- tty_kref_put(tty);
- }
+ port = &gsm->dlci[addr]->port;
+
+ if (bits & 2)
+ tty_insert_flip_char(port, 0, TTY_OVERRUN);
+ if (bits & 4)
+ tty_insert_flip_char(port, 0, TTY_PARITY);
+ if (bits & 8)
+ tty_insert_flip_char(port, 0, TTY_FRAME);
+
+ tty_flip_buffer_push(port);
+
gsm_control_reply(gsm, CMD_RLS, data, clen);
}
@@ -1190,6 +1205,8 @@ static void gsm_control_message(struct gsm_mux *gsm, unsigned int command,
u8 *data, int clen)
{
u8 buf[1];
+ unsigned long flags;
+
switch (command) {
case CMD_CLD: {
struct gsm_dlci *dlci = gsm->dlci[0];
@@ -1206,16 +1223,18 @@ static void gsm_control_message(struct gsm_mux *gsm, unsigned int command,
gsm_control_reply(gsm, CMD_TEST, data, clen);
break;
case CMD_FCON:
- /* Modem wants us to STFU */
- gsm->constipated = 1;
- gsm_control_reply(gsm, CMD_FCON, NULL, 0);
- break;
- case CMD_FCOFF:
/* Modem can accept data again */
gsm->constipated = 0;
- gsm_control_reply(gsm, CMD_FCOFF, NULL, 0);
+ gsm_control_reply(gsm, CMD_FCON, NULL, 0);
/* Kick the link in case it is idling */
+ spin_lock_irqsave(&gsm->tx_lock, flags);
gsm_data_kick(gsm);
+ spin_unlock_irqrestore(&gsm->tx_lock, flags);
+ break;
+ case CMD_FCOFF:
+ /* Modem wants us to STFU */
+ gsm->constipated = 1;
+ gsm_control_reply(gsm, CMD_FCOFF, NULL, 0);
break;
case CMD_MSC:
/* Out of band modem line change indicator for a DLCI */
@@ -1411,11 +1430,7 @@ static void gsm_dlci_close(struct gsm_dlci *dlci)
pr_debug("DLCI %d goes closed.\n", dlci->addr);
dlci->state = DLCI_CLOSED;
if (dlci->addr != 0) {
- struct tty_struct *tty = tty_port_tty_get(&dlci->port);
- if (tty) {
- tty_hangup(tty);
- tty_kref_put(tty);
- }
+ tty_port_tty_hangup(&dlci->port, false);
kfifo_reset(dlci->fifo);
} else
dlci->gsm->dead = 1;
@@ -1537,36 +1552,37 @@ static void gsm_dlci_data(struct gsm_dlci *dlci, u8 *data, int clen)
{
/* krefs .. */
struct tty_port *port = &dlci->port;
- struct tty_struct *tty = tty_port_tty_get(port);
+ struct tty_struct *tty;
unsigned int modem = 0;
int len = clen;
if (debug & 16)
- pr_debug("%d bytes for tty %p\n", len, tty);
- if (tty) {
- switch (dlci->adaption) {
- /* Unsupported types */
- /* Packetised interruptible data */
- case 4:
- break;
- /* Packetised uininterruptible voice/data */
- case 3:
- break;
- /* Asynchronous serial with line state in each frame */
- case 2:
- while (gsm_read_ea(&modem, *data++) == 0) {
- len--;
- if (len == 0)
- return;
- }
+ pr_debug("%d bytes for tty\n", len);
+ switch (dlci->adaption) {
+ /* Unsupported types */
+ /* Packetised interruptible data */
+ case 4:
+ break;
+ /* Packetised uininterruptible voice/data */
+ case 3:
+ break;
+ /* Asynchronous serial with line state in each frame */
+ case 2:
+ while (gsm_read_ea(&modem, *data++) == 0) {
+ len--;
+ if (len == 0)
+ return;
+ }
+ tty = tty_port_tty_get(port);
+ if (tty) {
gsm_process_modem(tty, dlci, modem, clen);
- /* Line state will go via DLCI 0 controls only */
- case 1:
- default:
- tty_insert_flip_string(tty, data, len);
- tty_flip_buffer_push(tty);
+ tty_kref_put(tty);
}
- tty_kref_put(tty);
+ /* Line state will go via DLCI 0 controls only */
+ case 1:
+ default:
+ tty_insert_flip_string(port, data, len);
+ tty_flip_buffer_push(port);
}
}
@@ -1626,7 +1642,6 @@ static struct gsm_dlci *gsm_dlci_alloc(struct gsm_mux *gsm, int addr)
if (dlci == NULL)
return NULL;
spin_lock_init(&dlci->lock);
- kref_init(&dlci->ref);
mutex_init(&dlci->mutex);
dlci->fifo = &dlci->_fifo;
if (kfifo_alloc(&dlci->_fifo, 4096, GFP_KERNEL) < 0) {
@@ -1660,28 +1675,30 @@ static struct gsm_dlci *gsm_dlci_alloc(struct gsm_mux *gsm, int addr)
*
* Can sleep.
*/
-static void gsm_dlci_free(struct kref *ref)
+static void gsm_dlci_free(struct tty_port *port)
{
- struct gsm_dlci *dlci = container_of(ref, struct gsm_dlci, ref);
+ struct gsm_dlci *dlci = container_of(port, struct gsm_dlci, port);
del_timer_sync(&dlci->t1);
dlci->gsm->dlci[dlci->addr] = NULL;
kfifo_free(dlci->fifo);
while ((dlci->skb = skb_dequeue(&dlci->skb_list)))
- kfree_skb(dlci->skb);
+ dev_kfree_skb(dlci->skb);
kfree(dlci);
}
static inline void dlci_get(struct gsm_dlci *dlci)
{
- kref_get(&dlci->ref);
+ tty_port_get(&dlci->port);
}
static inline void dlci_put(struct gsm_dlci *dlci)
{
- kref_put(&dlci->ref, gsm_dlci_free);
+ tty_port_put(&dlci->port);
}
+static void gsm_destroy_network(struct gsm_dlci *dlci);
+
/**
* gsm_dlci_release - release DLCI
* @dlci: DLCI to destroy
@@ -1695,9 +1712,16 @@ static void gsm_dlci_release(struct gsm_dlci *dlci)
{
struct tty_struct *tty = tty_port_tty_get(&dlci->port);
if (tty) {
+ mutex_lock(&dlci->mutex);
+ gsm_destroy_network(dlci);
+ mutex_unlock(&dlci->mutex);
+
tty_vhangup(tty);
+
+ tty_port_tty_set(&dlci->port, NULL);
tty_kref_put(tty);
}
+ dlci->state = DLCI_CLOSED;
dlci_put(dlci);
}
@@ -1725,10 +1749,11 @@ static void gsm_queue(struct gsm_mux *gsm)
if ((gsm->control & ~PF) == UI)
gsm->fcs = gsm_fcs_add_block(gsm->fcs, gsm->buf, gsm->len);
- if (gsm->encoding == 0){
- /* WARNING: gsm->received_fcs is used for gsm->encoding = 0 only.
- In this case it contain the last piece of data
- required to generate final CRC */
+ if (gsm->encoding == 0) {
+ /* WARNING: gsm->received_fcs is used for
+ gsm->encoding = 0 only.
+ In this case it contain the last piece of data
+ required to generate final CRC */
gsm->fcs = gsm_fcs_add(gsm->fcs, gsm->received_fcs);
}
if (gsm->fcs != GOOD_FCS) {
@@ -2003,11 +2028,11 @@ static void gsm_error(struct gsm_mux *gsm,
* and then shut down each device hanging up the channels as we go.
*/
-void gsm_cleanup_mux(struct gsm_mux *gsm)
+static void gsm_cleanup_mux(struct gsm_mux *gsm)
{
int i;
struct gsm_dlci *dlci = gsm->dlci[0];
- struct gsm_msg *txq;
+ struct gsm_msg *txq, *ntxq;
struct gsm_control *gc;
gsm->dead = 1;
@@ -2038,17 +2063,16 @@ void gsm_cleanup_mux(struct gsm_mux *gsm)
dlci->state == DLCI_CLOSED);
}
/* Free up any link layer users */
+ mutex_lock(&gsm->mutex);
for (i = 0; i < NUM_DLCI; i++)
if (gsm->dlci[i])
gsm_dlci_release(gsm->dlci[i]);
+ mutex_unlock(&gsm->mutex);
/* Now wipe the queues */
- for (txq = gsm->tx_head; txq != NULL; txq = gsm->tx_head) {
- gsm->tx_head = txq->next;
+ list_for_each_entry_safe(txq, ntxq, &gsm->tx_list, list)
kfree(txq);
- }
- gsm->tx_tail = NULL;
+ INIT_LIST_HEAD(&gsm->tx_list);
}
-EXPORT_SYMBOL_GPL(gsm_cleanup_mux);
/**
* gsm_activate_mux - generic GSM setup
@@ -2059,7 +2083,7 @@ EXPORT_SYMBOL_GPL(gsm_cleanup_mux);
* finally kick off connecting to DLCI 0 on the modem.
*/
-int gsm_activate_mux(struct gsm_mux *gsm)
+static int gsm_activate_mux(struct gsm_mux *gsm)
{
struct gsm_dlci *dlci;
int i = 0;
@@ -2095,7 +2119,6 @@ int gsm_activate_mux(struct gsm_mux *gsm)
gsm->dead = 0; /* Tty opens are now permissible */
return 0;
}
-EXPORT_SYMBOL_GPL(gsm_activate_mux);
/**
* gsm_free_mux - free up a mux
@@ -2103,13 +2126,12 @@ EXPORT_SYMBOL_GPL(gsm_activate_mux);
*
* Dispose of allocated resources for a dead mux
*/
-void gsm_free_mux(struct gsm_mux *gsm)
+static void gsm_free_mux(struct gsm_mux *gsm)
{
kfree(gsm->txframe);
kfree(gsm->buf);
kfree(gsm);
}
-EXPORT_SYMBOL_GPL(gsm_free_mux);
/**
* gsm_free_muxr - free up a mux
@@ -2139,7 +2161,7 @@ static inline void mux_put(struct gsm_mux *gsm)
* Creates a new mux ready for activation.
*/
-struct gsm_mux *gsm_alloc_mux(void)
+static struct gsm_mux *gsm_alloc_mux(void)
{
struct gsm_mux *gsm = kzalloc(sizeof(struct gsm_mux), GFP_KERNEL);
if (gsm == NULL)
@@ -2156,7 +2178,9 @@ struct gsm_mux *gsm_alloc_mux(void)
return NULL;
}
spin_lock_init(&gsm->lock);
+ mutex_init(&gsm->mutex);
kref_init(&gsm->ref);
+ INIT_LIST_HEAD(&gsm->tx_list);
gsm->t1 = T1;
gsm->t2 = T2;
@@ -2170,7 +2194,6 @@ struct gsm_mux *gsm_alloc_mux(void)
return gsm;
}
-EXPORT_SYMBOL_GPL(gsm_alloc_mux);
/**
* gsmld_output - write to link
@@ -2254,14 +2277,15 @@ static void gsmld_receive_buf(struct tty_struct *tty, const unsigned char *cp,
char *f;
int i;
char buf[64];
- char flags;
+ char flags = TTY_NORMAL;
if (debug & 4)
print_hex_dump_bytes("gsmld_receive: ", DUMP_PREFIX_OFFSET,
cp, count);
for (i = count, dp = cp, f = fp; i; i--, dp++) {
- flags = *f++;
+ if (f)
+ flags = *f++;
switch (flags) {
case TTY_NORMAL:
gsm->receive(gsm, *dp);
@@ -2273,7 +2297,7 @@ static void gsmld_receive_buf(struct tty_struct *tty, const unsigned char *cp,
gsm->error(gsm, *dp, flags);
break;
default:
- WARN_ONCE("%s: unknown flag %d\n",
+ WARN_ONCE(1, "%s: unknown flag %d\n",
tty_name(tty, buf), flags);
break;
}
@@ -2377,12 +2401,12 @@ static void gsmld_write_wakeup(struct tty_struct *tty)
/* Queue poll */
clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
+ spin_lock_irqsave(&gsm->tx_lock, flags);
gsm_data_kick(gsm);
if (gsm->tx_bytes < TX_THRESH_LO) {
- spin_lock_irqsave(&gsm->tx_lock, flags);
gsm_dlci_data_sweep(gsm);
- spin_unlock_irqrestore(&gsm->tx_lock, flags);
}
+ spin_unlock_irqrestore(&gsm->tx_lock, flags);
}
/**
@@ -2696,7 +2720,7 @@ static void gsm_mux_rx_netchar(struct gsm_dlci *dlci,
return;
}
-int gsm_change_mtu(struct net_device *net, int new_mtu)
+static int gsm_change_mtu(struct net_device *net, int new_mtu)
{
struct gsm_mux_net *mux_net = (struct gsm_mux_net *)netdev_priv(net);
if ((new_mtu < 8) || (new_mtu > mux_net->dlci->gsm->mtu))
@@ -2866,16 +2890,17 @@ static void gsm_dtr_rts(struct tty_port *port, int onoff)
static const struct tty_port_operations gsm_port_ops = {
.carrier_raised = gsm_carrier_raised,
.dtr_rts = gsm_dtr_rts,
+ .destruct = gsm_dlci_free,
};
-
-static int gsmtty_open(struct tty_struct *tty, struct file *filp)
+static int gsmtty_install(struct tty_driver *driver, struct tty_struct *tty)
{
struct gsm_mux *gsm;
struct gsm_dlci *dlci;
- struct tty_port *port;
unsigned int line = tty->index;
unsigned int mux = line >> 6;
+ bool alloc = false;
+ int ret;
line = line & 0x3F;
@@ -2889,17 +2914,47 @@ static int gsmtty_open(struct tty_struct *tty, struct file *filp)
gsm = gsm_mux[mux];
if (gsm->dead)
return -EL2HLT;
+ /* If DLCI 0 is not yet fully open return an error.
+ This is ok from a locking
+ perspective as we don't have to worry about this
+ if DLCI0 is lost */
+ mutex_lock(&gsm->mutex);
+ if (gsm->dlci[0] && gsm->dlci[0]->state != DLCI_OPEN) {
+ mutex_unlock(&gsm->mutex);
+ return -EL2NSYNC;
+ }
dlci = gsm->dlci[line];
- if (dlci == NULL)
+ if (dlci == NULL) {
+ alloc = true;
dlci = gsm_dlci_alloc(gsm, line);
- if (dlci == NULL)
+ }
+ if (dlci == NULL) {
+ mutex_unlock(&gsm->mutex);
return -ENOMEM;
- port = &dlci->port;
- port->count++;
- tty->driver_data = dlci;
+ }
+ ret = tty_port_install(&dlci->port, driver, tty);
+ if (ret) {
+ if (alloc)
+ dlci_put(dlci);
+ mutex_unlock(&gsm->mutex);
+ return ret;
+ }
+
dlci_get(dlci);
- dlci_get(dlci->gsm->dlci[0]);
- mux_get(dlci->gsm);
+ dlci_get(gsm->dlci[0]);
+ mux_get(gsm);
+ tty->driver_data = dlci;
+ mutex_unlock(&gsm->mutex);
+
+ return 0;
+}
+
+static int gsmtty_open(struct tty_struct *tty, struct file *filp)
+{
+ struct gsm_dlci *dlci = tty->driver_data;
+ struct tty_port *port = &dlci->port;
+
+ port->count++;
tty_port_tty_set(port, tty);
dlci->modem_rx = 0;
@@ -2919,24 +2974,29 @@ static void gsmtty_close(struct tty_struct *tty, struct file *filp)
if (dlci == NULL)
return;
+ if (dlci->state == DLCI_CLOSED)
+ return;
mutex_lock(&dlci->mutex);
gsm_destroy_network(dlci);
mutex_unlock(&dlci->mutex);
gsm = dlci->gsm;
if (tty_port_close_start(&dlci->port, tty, filp) == 0)
- goto out;
+ return;
gsm_dlci_begin_close(dlci);
+ if (test_bit(ASYNCB_INITIALIZED, &dlci->port.flags)) {
+ if (C_HUPCL(tty))
+ tty_port_lower_dtr_rts(&dlci->port);
+ }
tty_port_close_end(&dlci->port, tty);
tty_port_tty_set(&dlci->port, NULL);
-out:
- dlci_put(dlci);
- dlci_put(gsm->dlci[0]);
- mux_put(gsm);
+ return;
}
static void gsmtty_hangup(struct tty_struct *tty)
{
struct gsm_dlci *dlci = tty->driver_data;
+ if (dlci->state == DLCI_CLOSED)
+ return;
tty_port_hangup(&dlci->port);
gsm_dlci_begin_close(dlci);
}
@@ -2944,9 +3004,12 @@ static void gsmtty_hangup(struct tty_struct *tty)
static int gsmtty_write(struct tty_struct *tty, const unsigned char *buf,
int len)
{
+ int sent;
struct gsm_dlci *dlci = tty->driver_data;
+ if (dlci->state == DLCI_CLOSED)
+ return -EINVAL;
/* Stuff the bytes into the fifo queue */
- int sent = kfifo_in_locked(dlci->fifo, buf, len, &dlci->lock);
+ sent = kfifo_in_locked(dlci->fifo, buf, len, &dlci->lock);
/* Need to kick the channel */
gsm_dlci_data_kick(dlci);
return sent;
@@ -2955,18 +3018,24 @@ static int gsmtty_write(struct tty_struct *tty, const unsigned char *buf,
static int gsmtty_write_room(struct tty_struct *tty)
{
struct gsm_dlci *dlci = tty->driver_data;
+ if (dlci->state == DLCI_CLOSED)
+ return -EINVAL;
return TX_SIZE - kfifo_len(dlci->fifo);
}
static int gsmtty_chars_in_buffer(struct tty_struct *tty)
{
struct gsm_dlci *dlci = tty->driver_data;
+ if (dlci->state == DLCI_CLOSED)
+ return -EINVAL;
return kfifo_len(dlci->fifo);
}
static void gsmtty_flush_buffer(struct tty_struct *tty)
{
struct gsm_dlci *dlci = tty->driver_data;
+ if (dlci->state == DLCI_CLOSED)
+ return;
/* Caution needed: If we implement reliable transport classes
then the data being transmitted can't simply be junked once
it has first hit the stack. Until then we can just blow it
@@ -2985,6 +3054,8 @@ static void gsmtty_wait_until_sent(struct tty_struct *tty, int timeout)
static int gsmtty_tiocmget(struct tty_struct *tty)
{
struct gsm_dlci *dlci = tty->driver_data;
+ if (dlci->state == DLCI_CLOSED)
+ return -EINVAL;
return dlci->modem_rx;
}
@@ -2994,6 +3065,8 @@ static int gsmtty_tiocmset(struct tty_struct *tty,
struct gsm_dlci *dlci = tty->driver_data;
unsigned int modem_tx = dlci->modem_tx;
+ if (dlci->state == DLCI_CLOSED)
+ return -EINVAL;
modem_tx &= ~clear;
modem_tx |= set;
@@ -3012,6 +3085,8 @@ static int gsmtty_ioctl(struct tty_struct *tty,
struct gsm_netconfig nc;
int index;
+ if (dlci->state == DLCI_CLOSED)
+ return -EINVAL;
switch (cmd) {
case GSMIOC_ENABLE_NET:
if (copy_from_user(&nc, (void __user *)arg, sizeof(nc)))
@@ -3038,18 +3113,23 @@ static int gsmtty_ioctl(struct tty_struct *tty,
static void gsmtty_set_termios(struct tty_struct *tty, struct ktermios *old)
{
+ struct gsm_dlci *dlci = tty->driver_data;
+ if (dlci->state == DLCI_CLOSED)
+ return;
/* For the moment its fixed. In actual fact the speed information
for the virtual channel can be propogated in both directions by
the RPN control message. This however rapidly gets nasty as we
then have to remap modem signals each way according to whether
our virtual cable is null modem etc .. */
- tty_termios_copy_hw(tty->termios, old);
+ tty_termios_copy_hw(&tty->termios, old);
}
static void gsmtty_throttle(struct tty_struct *tty)
{
struct gsm_dlci *dlci = tty->driver_data;
- if (tty->termios->c_cflag & CRTSCTS)
+ if (dlci->state == DLCI_CLOSED)
+ return;
+ if (tty->termios.c_cflag & CRTSCTS)
dlci->modem_tx &= ~TIOCM_DTR;
dlci->throttled = 1;
/* Send an MSC with DTR cleared */
@@ -3059,7 +3139,9 @@ static void gsmtty_throttle(struct tty_struct *tty)
static void gsmtty_unthrottle(struct tty_struct *tty)
{
struct gsm_dlci *dlci = tty->driver_data;
- if (tty->termios->c_cflag & CRTSCTS)
+ if (dlci->state == DLCI_CLOSED)
+ return;
+ if (tty->termios.c_cflag & CRTSCTS)
dlci->modem_tx |= TIOCM_DTR;
dlci->throttled = 0;
/* Send an MSC with DTR set */
@@ -3070,6 +3152,8 @@ static int gsmtty_break_ctl(struct tty_struct *tty, int state)
{
struct gsm_dlci *dlci = tty->driver_data;
int encode = 0; /* Off */
+ if (dlci->state == DLCI_CLOSED)
+ return -EINVAL;
if (state == -1) /* "On indefinitely" - we can't encode this
properly */
@@ -3082,9 +3166,20 @@ static int gsmtty_break_ctl(struct tty_struct *tty, int state)
return gsmtty_modem_update(dlci, encode);
}
+static void gsmtty_remove(struct tty_driver *driver, struct tty_struct *tty)
+{
+ struct gsm_dlci *dlci = tty->driver_data;
+ struct gsm_mux *gsm = dlci->gsm;
+
+ dlci_put(dlci);
+ dlci_put(gsm->dlci[0]);
+ mux_put(gsm);
+ driver->ttys[tty->index] = NULL;
+}
/* Virtual ttys for the demux */
static const struct tty_operations gsmtty_ops = {
+ .install = gsmtty_install,
.open = gsmtty_open,
.close = gsmtty_close,
.write = gsmtty_write,
@@ -3100,6 +3195,7 @@ static const struct tty_operations gsmtty_ops = {
.tiocmget = gsmtty_tiocmget,
.tiocmset = gsmtty_tiocmset,
.break_ctl = gsmtty_break_ctl,
+ .remove = gsmtty_remove,
};
@@ -3120,7 +3216,6 @@ static int __init gsm_init(void)
pr_err("gsm_init: tty allocation failed.\n");
return -EINVAL;
}
- gsm_tty_driver->owner = THIS_MODULE;
gsm_tty_driver->driver_name = "gsmtty";
gsm_tty_driver->name = "gsmtty";
gsm_tty_driver->major = 0; /* Dynamic */
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2025-11-09 15:37:06 +0000