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authorLinus Torvalds <torvalds@linux-foundation.org>2011-07-25 23:09:27 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2011-07-25 23:09:27 -0700
commitd5ef642355bdd9b383ff5c18cbc6102a06eecbaf (patch)
treefcf78d33c1790c6c24efbfd0c3695f7874f053d7 /drivers/tty/n_gsm.c
parentf549953c15deab4c54708b39af86d4edecc6cddc (diff)
parentdef90f4239f094f3846c108c1c41a4cd55c33e8e (diff)
Merge branch 'tty-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty-2.6
* 'tty-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty-2.6: (26 commits) amba pl011: workaround for uart registers lockup n_gsm: fix the wrong FCS handling pch_uart: add missing comment about OKI ML7223 pch_uart: Add MSI support tty: fix "IRQ45: nobody cared" PTI feature to allow user to name and mark masterchannel request. 0 for o PTI Makefile bug. tty: serial: samsung.c remove legacy PM code. SERIAL: SC26xx: Fix link error. serial: mrst_max3110: initialize waitqueue earlier mrst_max3110: Change max missing message priority. tty: s5pv210: Add delay loop on fifo reset function for UART tty/serial: Fix XSCALE serial ports, e.g. ce4100 serial: bfin_5xx: fix off-by-one with resource size drivers/tty: use printk_ratelimited() instead of printk_ratelimit() tty: n_gsm: Added refcount usage to gsm_mux and gsm_dlci structs tty: n_gsm: Add raw-ip support tty: n_gsm: expose gsmtty device nodes at ldisc open time pch_phub: Fix register miss-setting issue serial: 8250, increase PASS_LIMIT ...
Diffstat (limited to 'drivers/tty/n_gsm.c')
-rw-r--r--drivers/tty/n_gsm.c401
1 files changed, 372 insertions, 29 deletions
diff --git a/drivers/tty/n_gsm.c b/drivers/tty/n_gsm.c
index 19b4ae052af8..8a50e4eebf18 100644
--- a/drivers/tty/n_gsm.c
+++ b/drivers/tty/n_gsm.c
@@ -58,6 +58,10 @@
#include <linux/serial.h>
#include <linux/kfifo.h>
#include <linux/skbuff.h>
+#include <net/arp.h>
+#include <linux/ip.h>
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h>
#include <linux/gsmmux.h>
static int debug;
@@ -77,8 +81,24 @@ module_param(debug, int, 0600);
* Semi-arbitrary buffer size limits. 0710 is normally run with 32-64 byte
* limits so this is plenty
*/
-#define MAX_MRU 512
-#define MAX_MTU 512
+#define MAX_MRU 1500
+#define MAX_MTU 1500
+#define GSM_NET_TX_TIMEOUT (HZ*10)
+
+/**
+ * struct gsm_mux_net - network interface
+ * @struct gsm_dlci* dlci
+ * @struct net_device_stats stats;
+ *
+ * Created when net interface is initialized.
+ **/
+struct gsm_mux_net {
+ struct kref ref;
+ struct gsm_dlci *dlci;
+ struct net_device_stats stats;
+};
+
+#define STATS(net) (((struct gsm_mux_net *)netdev_priv(net))->stats)
/*
* Each block of data we have queued to go out is in the form of
@@ -113,6 +133,8 @@ 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 */
spinlock_t lock; /* Protects the internal state */
@@ -123,6 +145,7 @@ struct gsm_dlci {
struct kfifo *fifo; /* Queue fifo for the DLCI */
struct kfifo _fifo; /* For new fifo API porting only */
int adaption; /* Adaption layer in use */
+ int prev_adaption;
u32 modem_rx; /* Our incoming virtual modem lines */
u32 modem_tx; /* Our outgoing modem lines */
int dead; /* Refuse re-open */
@@ -134,6 +157,8 @@ struct gsm_dlci {
struct sk_buff_head skb_list; /* Queued frames */
/* Data handling callback */
void (*data)(struct gsm_dlci *dlci, u8 *data, int len);
+ void (*prev_data)(struct gsm_dlci *dlci, u8 *data, int len);
+ struct net_device *net; /* network interface, if created */
};
/* DLCI 0, 62/63 are special or reseved see gsmtty_open */
@@ -169,6 +194,8 @@ struct gsm_control {
struct gsm_mux {
struct tty_struct *tty; /* The tty our ldisc is bound to */
spinlock_t lock;
+ unsigned int num;
+ struct kref ref;
/* Events on the GSM channel */
wait_queue_head_t event;
@@ -250,6 +277,8 @@ struct gsm_mux {
static struct gsm_mux *gsm_mux[MAX_MUX]; /* GSM muxes */
static spinlock_t gsm_mux_lock;
+static struct tty_driver *gsm_tty_driver;
+
/*
* This section of the driver logic implements the GSM encodings
* both the basic and the 'advanced'. Reliable transport is not
@@ -878,8 +907,10 @@ static int gsm_dlci_data_output_framed(struct gsm_mux *gsm,
memcpy(dp, dlci->skb->data, len);
skb_pull(dlci->skb, len);
__gsm_data_queue(dlci, msg);
- if (last)
+ if (last) {
+ kfree_skb(dlci->skb);
dlci->skb = NULL;
+ }
return size;
}
@@ -912,7 +943,7 @@ static void gsm_dlci_data_sweep(struct gsm_mux *gsm)
i++;
continue;
}
- if (dlci->adaption < 3)
+ if (dlci->adaption < 3 && !dlci->net)
len = gsm_dlci_data_output(gsm, dlci);
else
len = gsm_dlci_data_output_framed(gsm, dlci);
@@ -939,9 +970,12 @@ static void gsm_dlci_data_kick(struct gsm_dlci *dlci)
spin_lock_irqsave(&dlci->gsm->tx_lock, flags);
/* If we have nothing running then we need to fire up */
- if (dlci->gsm->tx_bytes == 0)
- gsm_dlci_data_output(dlci->gsm, dlci);
- else if (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)
gsm_dlci_data_sweep(dlci->gsm);
spin_unlock_irqrestore(&dlci->gsm->tx_lock, flags);
}
@@ -1588,6 +1622,8 @@ 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) {
kfree(dlci);
@@ -1613,26 +1649,52 @@ static struct gsm_dlci *gsm_dlci_alloc(struct gsm_mux *gsm, int addr)
}
/**
- * gsm_dlci_free - release DLCI
+ * gsm_dlci_free - free DLCI
+ * @dlci: DLCI to free
+ *
+ * Free up a DLCI.
+ *
+ * Can sleep.
+ */
+static void gsm_dlci_free(struct kref *ref)
+{
+ struct gsm_dlci *dlci = container_of(ref, struct gsm_dlci, ref);
+
+ 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);
+ kfree(dlci);
+}
+
+static inline void dlci_get(struct gsm_dlci *dlci)
+{
+ kref_get(&dlci->ref);
+}
+
+static inline void dlci_put(struct gsm_dlci *dlci)
+{
+ kref_put(&dlci->ref, gsm_dlci_free);
+}
+
+/**
+ * gsm_dlci_release - release DLCI
* @dlci: DLCI to destroy
*
- * Free up a DLCI. Currently to keep the lifetime rules sane we only
- * clean up DLCI objects when the MUX closes rather than as the port
- * is closed down on both the tty and mux levels.
+ * Release a DLCI. Actual free is deferred until either
+ * mux is closed or tty is closed - whichever is last.
*
* Can sleep.
*/
-static void gsm_dlci_free(struct gsm_dlci *dlci)
+static void gsm_dlci_release(struct gsm_dlci *dlci)
{
struct tty_struct *tty = tty_port_tty_get(&dlci->port);
if (tty) {
tty_vhangup(tty);
tty_kref_put(tty);
}
- del_timer_sync(&dlci->t1);
- dlci->gsm->dlci[dlci->addr] = NULL;
- kfifo_free(dlci->fifo);
- kfree(dlci);
+ dlci_put(dlci);
}
/*
@@ -1823,10 +1885,6 @@ static void gsm0_receive(struct gsm_mux *gsm, unsigned char c)
break;
case GSM_FCS: /* FCS follows the packet */
gsm->received_fcs = c;
- if (c == GSM0_SOF) {
- gsm->state = GSM_SEARCH;
- break;
- }
gsm_queue(gsm);
gsm->state = GSM_SSOF;
break;
@@ -1970,7 +2028,7 @@ void gsm_cleanup_mux(struct gsm_mux *gsm)
/* Free up any link layer users */
for (i = 0; i < NUM_DLCI; i++)
if (gsm->dlci[i])
- gsm_dlci_free(gsm->dlci[i]);
+ gsm_dlci_release(gsm->dlci[i]);
/* Now wipe the queues */
for (txq = gsm->tx_head; txq != NULL; txq = gsm->tx_head) {
gsm->tx_head = txq->next;
@@ -2010,6 +2068,7 @@ int gsm_activate_mux(struct gsm_mux *gsm)
spin_lock(&gsm_mux_lock);
for (i = 0; i < MAX_MUX; i++) {
if (gsm_mux[i] == NULL) {
+ gsm->num = i;
gsm_mux[i] = gsm;
break;
}
@@ -2030,8 +2089,7 @@ EXPORT_SYMBOL_GPL(gsm_activate_mux);
* gsm_free_mux - free up a mux
* @mux: mux to free
*
- * Dispose of allocated resources for a dead mux. No refcounting
- * at present so the mux must be truly dead.
+ * Dispose of allocated resources for a dead mux
*/
void gsm_free_mux(struct gsm_mux *gsm)
{
@@ -2042,6 +2100,28 @@ void gsm_free_mux(struct gsm_mux *gsm)
EXPORT_SYMBOL_GPL(gsm_free_mux);
/**
+ * gsm_free_muxr - free up a mux
+ * @mux: mux to free
+ *
+ * Dispose of allocated resources for a dead mux
+ */
+static void gsm_free_muxr(struct kref *ref)
+{
+ struct gsm_mux *gsm = container_of(ref, struct gsm_mux, ref);
+ gsm_free_mux(gsm);
+}
+
+static inline void mux_get(struct gsm_mux *gsm)
+{
+ kref_get(&gsm->ref);
+}
+
+static inline void mux_put(struct gsm_mux *gsm)
+{
+ kref_put(&gsm->ref, gsm_free_muxr);
+}
+
+/**
* gsm_alloc_mux - allocate a mux
*
* Creates a new mux ready for activation.
@@ -2064,12 +2144,12 @@ struct gsm_mux *gsm_alloc_mux(void)
return NULL;
}
spin_lock_init(&gsm->lock);
+ kref_init(&gsm->ref);
gsm->t1 = T1;
gsm->t2 = T2;
gsm->n2 = N2;
gsm->ftype = UIH;
- gsm->initiator = 0;
gsm->adaption = 1;
gsm->encoding = 1;
gsm->mru = 64; /* Default to encoding 1 so these should be 64 */
@@ -2115,13 +2195,20 @@ static int gsmld_output(struct gsm_mux *gsm, u8 *data, int len)
static int gsmld_attach_gsm(struct tty_struct *tty, struct gsm_mux *gsm)
{
- int ret;
+ int ret, i;
+ int base = gsm->num << 6; /* Base for this MUX */
gsm->tty = tty_kref_get(tty);
gsm->output = gsmld_output;
ret = gsm_activate_mux(gsm);
if (ret != 0)
tty_kref_put(gsm->tty);
+ else {
+ /* Don't register device 0 - this is the control channel and not
+ a usable tty interface */
+ for (i = 1; i < NUM_DLCI; i++)
+ tty_register_device(gsm_tty_driver, base + i, NULL);
+ }
return ret;
}
@@ -2136,7 +2223,12 @@ static int gsmld_attach_gsm(struct tty_struct *tty, struct gsm_mux *gsm)
static void gsmld_detach_gsm(struct tty_struct *tty, struct gsm_mux *gsm)
{
+ int i;
+ int base = gsm->num << 6; /* Base for this MUX */
+
WARN_ON(tty != gsm->tty);
+ for (i = 1; i < NUM_DLCI; i++)
+ tty_unregister_device(gsm_tty_driver, base + i);
gsm_cleanup_mux(gsm);
tty_kref_put(gsm->tty);
gsm->tty = NULL;
@@ -2224,7 +2316,7 @@ static void gsmld_close(struct tty_struct *tty)
gsmld_flush_buffer(tty);
/* Do other clean up here */
- gsm_free_mux(gsm);
+ mux_put(gsm);
}
/**
@@ -2476,6 +2568,220 @@ static int gsmld_ioctl(struct tty_struct *tty, struct file *file,
}
}
+/*
+ * Network interface
+ *
+ */
+
+static int gsm_mux_net_open(struct net_device *net)
+{
+ pr_debug("%s called\n", __func__);
+ netif_start_queue(net);
+ return 0;
+}
+
+static int gsm_mux_net_close(struct net_device *net)
+{
+ netif_stop_queue(net);
+ return 0;
+}
+
+static struct net_device_stats *gsm_mux_net_get_stats(struct net_device *net)
+{
+ return &((struct gsm_mux_net *)netdev_priv(net))->stats;
+}
+static void dlci_net_free(struct gsm_dlci *dlci)
+{
+ if (!dlci->net) {
+ WARN_ON(1);
+ return;
+ }
+ dlci->adaption = dlci->prev_adaption;
+ dlci->data = dlci->prev_data;
+ free_netdev(dlci->net);
+ dlci->net = NULL;
+}
+static void net_free(struct kref *ref)
+{
+ struct gsm_mux_net *mux_net;
+ struct gsm_dlci *dlci;
+
+ mux_net = container_of(ref, struct gsm_mux_net, ref);
+ dlci = mux_net->dlci;
+
+ if (dlci->net) {
+ unregister_netdev(dlci->net);
+ dlci_net_free(dlci);
+ }
+}
+
+static inline void muxnet_get(struct gsm_mux_net *mux_net)
+{
+ kref_get(&mux_net->ref);
+}
+
+static inline void muxnet_put(struct gsm_mux_net *mux_net)
+{
+ kref_put(&mux_net->ref, net_free);
+}
+
+static int gsm_mux_net_start_xmit(struct sk_buff *skb,
+ struct net_device *net)
+{
+ struct gsm_mux_net *mux_net = (struct gsm_mux_net *)netdev_priv(net);
+ struct gsm_dlci *dlci = mux_net->dlci;
+ muxnet_get(mux_net);
+
+ skb_queue_head(&dlci->skb_list, skb);
+ STATS(net).tx_packets++;
+ STATS(net).tx_bytes += skb->len;
+ gsm_dlci_data_kick(dlci);
+ /* And tell the kernel when the last transmit started. */
+ net->trans_start = jiffies;
+ muxnet_put(mux_net);
+ return NETDEV_TX_OK;
+}
+
+/* called when a packet did not ack after watchdogtimeout */
+static void gsm_mux_net_tx_timeout(struct net_device *net)
+{
+ /* Tell syslog we are hosed. */
+ dev_dbg(&net->dev, "Tx timed out.\n");
+
+ /* Update statistics */
+ STATS(net).tx_errors++;
+}
+
+static void gsm_mux_rx_netchar(struct gsm_dlci *dlci,
+ unsigned char *in_buf, int size)
+{
+ struct net_device *net = dlci->net;
+ struct sk_buff *skb;
+ struct gsm_mux_net *mux_net = (struct gsm_mux_net *)netdev_priv(net);
+ muxnet_get(mux_net);
+
+ /* Allocate an sk_buff */
+ skb = dev_alloc_skb(size + NET_IP_ALIGN);
+ if (!skb) {
+ /* We got no receive buffer. */
+ STATS(net).rx_dropped++;
+ muxnet_put(mux_net);
+ return;
+ }
+ skb_reserve(skb, NET_IP_ALIGN);
+ memcpy(skb_put(skb, size), in_buf, size);
+
+ skb->dev = net;
+ skb->protocol = __constant_htons(ETH_P_IP);
+
+ /* Ship it off to the kernel */
+ netif_rx(skb);
+
+ /* update out statistics */
+ STATS(net).rx_packets++;
+ STATS(net).rx_bytes += size;
+ muxnet_put(mux_net);
+ return;
+}
+
+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))
+ return -EINVAL;
+ net->mtu = new_mtu;
+ return 0;
+}
+
+static void gsm_mux_net_init(struct net_device *net)
+{
+ static const struct net_device_ops gsm_netdev_ops = {
+ .ndo_open = gsm_mux_net_open,
+ .ndo_stop = gsm_mux_net_close,
+ .ndo_start_xmit = gsm_mux_net_start_xmit,
+ .ndo_tx_timeout = gsm_mux_net_tx_timeout,
+ .ndo_get_stats = gsm_mux_net_get_stats,
+ .ndo_change_mtu = gsm_change_mtu,
+ };
+
+ net->netdev_ops = &gsm_netdev_ops;
+
+ /* fill in the other fields */
+ net->watchdog_timeo = GSM_NET_TX_TIMEOUT;
+ net->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
+ net->type = ARPHRD_NONE;
+ net->tx_queue_len = 10;
+}
+
+
+/* caller holds the dlci mutex */
+static void gsm_destroy_network(struct gsm_dlci *dlci)
+{
+ struct gsm_mux_net *mux_net;
+
+ pr_debug("destroy network interface");
+ if (!dlci->net)
+ return;
+ mux_net = (struct gsm_mux_net *)netdev_priv(dlci->net);
+ muxnet_put(mux_net);
+}
+
+
+/* caller holds the dlci mutex */
+static int gsm_create_network(struct gsm_dlci *dlci, struct gsm_netconfig *nc)
+{
+ char *netname;
+ int retval = 0;
+ struct net_device *net;
+ struct gsm_mux_net *mux_net;
+
+ if (!capable(CAP_NET_ADMIN))
+ return -EPERM;
+
+ /* Already in a non tty mode */
+ if (dlci->adaption > 2)
+ return -EBUSY;
+
+ if (nc->protocol != htons(ETH_P_IP))
+ return -EPROTONOSUPPORT;
+
+ if (nc->adaption != 3 && nc->adaption != 4)
+ return -EPROTONOSUPPORT;
+
+ pr_debug("create network interface");
+
+ netname = "gsm%d";
+ if (nc->if_name[0] != '\0')
+ netname = nc->if_name;
+ net = alloc_netdev(sizeof(struct gsm_mux_net),
+ netname,
+ gsm_mux_net_init);
+ if (!net) {
+ pr_err("alloc_netdev failed");
+ return -ENOMEM;
+ }
+ net->mtu = dlci->gsm->mtu;
+ mux_net = (struct gsm_mux_net *)netdev_priv(net);
+ mux_net->dlci = dlci;
+ kref_init(&mux_net->ref);
+ strncpy(nc->if_name, net->name, IFNAMSIZ); /* return net name */
+
+ /* reconfigure dlci for network */
+ dlci->prev_adaption = dlci->adaption;
+ dlci->prev_data = dlci->data;
+ dlci->adaption = nc->adaption;
+ dlci->data = gsm_mux_rx_netchar;
+ dlci->net = net;
+
+ pr_debug("register netdev");
+ retval = register_netdev(net);
+ if (retval) {
+ pr_err("network register fail %d\n", retval);
+ dlci_net_free(dlci);
+ return retval;
+ }
+ return net->ifindex; /* return network index */
+}
/* Line discipline for real tty */
struct tty_ldisc_ops tty_ldisc_packet = {
@@ -2579,6 +2885,9 @@ static int gsmtty_open(struct tty_struct *tty, struct file *filp)
port = &dlci->port;
port->count++;
tty->driver_data = dlci;
+ dlci_get(dlci);
+ dlci_get(dlci->gsm->dlci[0]);
+ mux_get(dlci->gsm);
tty_port_tty_set(port, tty);
dlci->modem_rx = 0;
@@ -2594,13 +2903,23 @@ static int gsmtty_open(struct tty_struct *tty, struct file *filp)
static void gsmtty_close(struct tty_struct *tty, struct file *filp)
{
struct gsm_dlci *dlci = tty->driver_data;
+ struct gsm_mux *gsm;
+
if (dlci == NULL)
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)
- return;
+ goto out;
gsm_dlci_begin_close(dlci);
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);
}
static void gsmtty_hangup(struct tty_struct *tty)
@@ -2677,7 +2996,32 @@ static int gsmtty_tiocmset(struct tty_struct *tty,
static int gsmtty_ioctl(struct tty_struct *tty,
unsigned int cmd, unsigned long arg)
{
- return -ENOIOCTLCMD;
+ struct gsm_dlci *dlci = tty->driver_data;
+ struct gsm_netconfig nc;
+ int index;
+
+ switch (cmd) {
+ case GSMIOC_ENABLE_NET:
+ if (copy_from_user(&nc, (void __user *)arg, sizeof(nc)))
+ return -EFAULT;
+ nc.if_name[IFNAMSIZ-1] = '\0';
+ /* return net interface index or error code */
+ mutex_lock(&dlci->mutex);
+ index = gsm_create_network(dlci, &nc);
+ mutex_unlock(&dlci->mutex);
+ if (copy_to_user((void __user *)arg, &nc, sizeof(nc)))
+ return -EFAULT;
+ return index;
+ case GSMIOC_DISABLE_NET:
+ if (!capable(CAP_NET_ADMIN))
+ return -EPERM;
+ mutex_lock(&dlci->mutex);
+ gsm_destroy_network(dlci);
+ mutex_unlock(&dlci->mutex);
+ return 0;
+ default:
+ return -ENOIOCTLCMD;
+ }
}
static void gsmtty_set_termios(struct tty_struct *tty, struct ktermios *old)
@@ -2726,7 +3070,6 @@ static int gsmtty_break_ctl(struct tty_struct *tty, int state)
return gsmtty_modem_update(dlci, encode);
}
-static struct tty_driver *gsm_tty_driver;
/* Virtual ttys for the demux */
static const struct tty_operations gsmtty_ops = {