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authorDavid S. Miller <davem@davemloft.net>2013-09-03 21:45:31 -0400
committerDavid S. Miller <davem@davemloft.net>2013-09-03 21:45:31 -0400
commite7abfe40928f4f8c1aa908477c36c13843bd1a57 (patch)
tree968d10a574b9de702b1c79345ae44afd5c404462 /net/bluetooth/rfcomm/tty.c
parentb1b72076b90d631637497b35e36bc64254df199d (diff)
parent0d8165e9fca119b804de2cf35674e07c36c9704f (diff)
Merge branch 'for-davem' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless-next
John W. Linville says: ==================== Please accept this batch of updates intended for the 3.12 stream. For the mac80211 bits, Johannes says this: "This time I have various improvements all over the place: IBSS, mesh, testmode, AP client powersave handling, one of the rare rfkill patches and some code cleanup." Also for mac80211: "And I also have some more changes for -next, just a few small fixes and improvements, nothing really stands out." And for iwlwifi: "This time I have some powersave work (notably uAPSD support), CQM offloads, support for a new firmware API and various code cleanups." Regarding the Bluetooth bits, Gustavo says: "Patches to 3.12, here we have: * implementation of a proper tty_port for RFCOMM devices, this fixes some issues people were seeing lately in the kernel. * Add voice_setting option for SCO, it is used for SCO Codec selection * bugfixes, small improvements and clean ups" For the NFC bits, Samuel says: "With this one we have: - A few pn533 improvements and minor fixes. Testing our pn533 driver against Google's NCI stack triggered a few issues that we fixed now. We also added Tx fragmentation support to this driver. - More NFC secure element handling. We added a GET_SE netlink command for getting all the discovered secure elements, and we defined 2 additional secure element netlink event (transaction and connectivity). We also fixed a couple of typos and copy-paste bugs from the secure element handling code. - Firmware download support for the pn544 driver. This chipset can enter a special mode where it's waiting for firmware blobs to replace the already flashed one. We now support that mode." With repect to the ath tree, Kalle says: "New features in ath10k are rx/tx checsumming in hw and survey scan implemented by Michal. Also he made fixes to different areas of the driver, most notable being fixing the case when using two streams and reducing the number of interface combinations to avoid firmware crashes. Bartosz did a clean related to how we handle SoC power save in PCI layer. For ath6kl Mohammed and Vasanth sent each a patch to fix two infrequent crashes." I also pulled the wireless tree into wireless-next to support a request from Johannes. On top of all that, there are the usual sort of driver updates. The mwifiex, brcmfmac, brcmsmac, ath9k, and rt2x00 drivers all get some attention, as does the bcma bus and a few other random bits here and there. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/bluetooth/rfcomm/tty.c')
-rw-r--r--net/bluetooth/rfcomm/tty.c271
1 files changed, 126 insertions, 145 deletions
diff --git a/net/bluetooth/rfcomm/tty.c b/net/bluetooth/rfcomm/tty.c
index b6e44ad6cca6..6d126faf145f 100644
--- a/net/bluetooth/rfcomm/tty.c
+++ b/net/bluetooth/rfcomm/tty.c
@@ -58,7 +58,6 @@ struct rfcomm_dev {
uint modem_status;
struct rfcomm_dlc *dlc;
- wait_queue_head_t wait;
struct device *tty_dev;
@@ -76,13 +75,6 @@ static void rfcomm_dev_modem_status(struct rfcomm_dlc *dlc, u8 v24_sig);
/* ---- Device functions ---- */
-/*
- * The reason this isn't actually a race, as you no doubt have a little voice
- * screaming at you in your head, is that the refcount should never actually
- * reach zero unless the device has already been taken off the list, in
- * rfcomm_dev_del(). And if that's not true, we'll hit the BUG() in
- * rfcomm_dev_destruct() anyway.
- */
static void rfcomm_dev_destruct(struct tty_port *port)
{
struct rfcomm_dev *dev = container_of(port, struct rfcomm_dev, port);
@@ -90,10 +82,9 @@ static void rfcomm_dev_destruct(struct tty_port *port)
BT_DBG("dev %p dlc %p", dev, dlc);
- /* Refcount should only hit zero when called from rfcomm_dev_del()
- which will have taken us off the list. Everything else are
- refcounting bugs. */
- BUG_ON(!list_empty(&dev->list));
+ spin_lock(&rfcomm_dev_lock);
+ list_del(&dev->list);
+ spin_unlock(&rfcomm_dev_lock);
rfcomm_dlc_lock(dlc);
/* Detach DLC if it's owned by this dev */
@@ -112,8 +103,39 @@ static void rfcomm_dev_destruct(struct tty_port *port)
module_put(THIS_MODULE);
}
+/* device-specific initialization: open the dlc */
+static int rfcomm_dev_activate(struct tty_port *port, struct tty_struct *tty)
+{
+ struct rfcomm_dev *dev = container_of(port, struct rfcomm_dev, port);
+
+ return rfcomm_dlc_open(dev->dlc, &dev->src, &dev->dst, dev->channel);
+}
+
+/* we block the open until the dlc->state becomes BT_CONNECTED */
+static int rfcomm_dev_carrier_raised(struct tty_port *port)
+{
+ struct rfcomm_dev *dev = container_of(port, struct rfcomm_dev, port);
+
+ return (dev->dlc->state == BT_CONNECTED);
+}
+
+/* device-specific cleanup: close the dlc */
+static void rfcomm_dev_shutdown(struct tty_port *port)
+{
+ struct rfcomm_dev *dev = container_of(port, struct rfcomm_dev, port);
+
+ if (dev->tty_dev->parent)
+ device_move(dev->tty_dev, NULL, DPM_ORDER_DEV_LAST);
+
+ /* close the dlc */
+ rfcomm_dlc_close(dev->dlc, 0);
+}
+
static const struct tty_port_operations rfcomm_port_ops = {
.destruct = rfcomm_dev_destruct,
+ .activate = rfcomm_dev_activate,
+ .shutdown = rfcomm_dev_shutdown,
+ .carrier_raised = rfcomm_dev_carrier_raised,
};
static struct rfcomm_dev *__rfcomm_dev_get(int id)
@@ -236,7 +258,6 @@ static int rfcomm_dev_add(struct rfcomm_dev_req *req, struct rfcomm_dlc *dlc)
tty_port_init(&dev->port);
dev->port.ops = &rfcomm_port_ops;
- init_waitqueue_head(&dev->wait);
skb_queue_head_init(&dev->pending);
@@ -282,7 +303,9 @@ out:
dev->id, NULL);
if (IS_ERR(dev->tty_dev)) {
err = PTR_ERR(dev->tty_dev);
+ spin_lock(&rfcomm_dev_lock);
list_del(&dev->list);
+ spin_unlock(&rfcomm_dev_lock);
goto free;
}
@@ -301,27 +324,6 @@ free:
return err;
}
-static void rfcomm_dev_del(struct rfcomm_dev *dev)
-{
- unsigned long flags;
- BT_DBG("dev %p", dev);
-
- BUG_ON(test_and_set_bit(RFCOMM_TTY_RELEASED, &dev->flags));
-
- spin_lock_irqsave(&dev->port.lock, flags);
- if (dev->port.count > 0) {
- spin_unlock_irqrestore(&dev->port.lock, flags);
- return;
- }
- spin_unlock_irqrestore(&dev->port.lock, flags);
-
- spin_lock(&rfcomm_dev_lock);
- list_del_init(&dev->list);
- spin_unlock(&rfcomm_dev_lock);
-
- tty_port_put(&dev->port);
-}
-
/* ---- Send buffer ---- */
static inline unsigned int rfcomm_room(struct rfcomm_dlc *dlc)
{
@@ -333,10 +335,9 @@ static inline unsigned int rfcomm_room(struct rfcomm_dlc *dlc)
static void rfcomm_wfree(struct sk_buff *skb)
{
struct rfcomm_dev *dev = (void *) skb->sk;
- struct tty_struct *tty = dev->port.tty;
atomic_sub(skb->truesize, &dev->wmem_alloc);
- if (test_bit(RFCOMM_TTY_ATTACHED, &dev->flags) && tty)
- tty_wakeup(tty);
+ if (test_bit(RFCOMM_TTY_ATTACHED, &dev->flags))
+ tty_port_tty_wakeup(&dev->port);
tty_port_put(&dev->port);
}
@@ -410,6 +411,7 @@ static int rfcomm_release_dev(void __user *arg)
{
struct rfcomm_dev_req req;
struct rfcomm_dev *dev;
+ struct tty_struct *tty;
if (copy_from_user(&req, arg, sizeof(req)))
return -EFAULT;
@@ -429,11 +431,15 @@ static int rfcomm_release_dev(void __user *arg)
rfcomm_dlc_close(dev->dlc, 0);
/* Shut down TTY synchronously before freeing rfcomm_dev */
- if (dev->port.tty)
- tty_vhangup(dev->port.tty);
+ tty = tty_port_tty_get(&dev->port);
+ if (tty) {
+ tty_vhangup(tty);
+ tty_kref_put(tty);
+ }
+
+ if (!test_and_set_bit(RFCOMM_TTY_RELEASED, &dev->flags))
+ tty_port_put(&dev->port);
- if (!test_bit(RFCOMM_RELEASE_ONHUP, &dev->flags))
- rfcomm_dev_del(dev);
tty_port_put(&dev->port);
return 0;
}
@@ -563,16 +569,21 @@ static void rfcomm_dev_data_ready(struct rfcomm_dlc *dlc, struct sk_buff *skb)
static void rfcomm_dev_state_change(struct rfcomm_dlc *dlc, int err)
{
struct rfcomm_dev *dev = dlc->owner;
+ struct tty_struct *tty;
if (!dev)
return;
BT_DBG("dlc %p dev %p err %d", dlc, dev, err);
dev->err = err;
- wake_up_interruptible(&dev->wait);
+ if (dlc->state == BT_CONNECTED) {
+ device_move(dev->tty_dev, rfcomm_get_device(dev),
+ DPM_ORDER_DEV_AFTER_PARENT);
- if (dlc->state == BT_CLOSED) {
- if (!dev->port.tty) {
+ wake_up_interruptible(&dev->port.open_wait);
+ } else if (dlc->state == BT_CLOSED) {
+ tty = tty_port_tty_get(&dev->port);
+ if (!tty) {
if (test_bit(RFCOMM_RELEASE_ONHUP, &dev->flags)) {
/* Drop DLC lock here to avoid deadlock
* 1. rfcomm_dev_get will take rfcomm_dev_lock
@@ -580,6 +591,9 @@ static void rfcomm_dev_state_change(struct rfcomm_dlc *dlc, int err)
* rfcomm_dev_lock -> dlc lock
* 2. tty_port_put will deadlock if it's
* the last reference
+ *
+ * FIXME: when we release the lock anything
+ * could happen to dev, even its destruction
*/
rfcomm_dlc_unlock(dlc);
if (rfcomm_dev_get(dev->id) == NULL) {
@@ -587,12 +601,17 @@ static void rfcomm_dev_state_change(struct rfcomm_dlc *dlc, int err)
return;
}
- rfcomm_dev_del(dev);
+ if (!test_and_set_bit(RFCOMM_TTY_RELEASED,
+ &dev->flags))
+ tty_port_put(&dev->port);
+
tty_port_put(&dev->port);
rfcomm_dlc_lock(dlc);
}
- } else
- tty_hangup(dev->port.tty);
+ } else {
+ tty_hangup(tty);
+ tty_kref_put(tty);
+ }
}
}
@@ -604,10 +623,8 @@ static void rfcomm_dev_modem_status(struct rfcomm_dlc *dlc, u8 v24_sig)
BT_DBG("dlc %p dev %p v24_sig 0x%02x", dlc, dev, v24_sig);
- if ((dev->modem_status & TIOCM_CD) && !(v24_sig & RFCOMM_V24_DV)) {
- if (dev->port.tty && !C_CLOCAL(dev->port.tty))
- tty_hangup(dev->port.tty);
- }
+ if ((dev->modem_status & TIOCM_CD) && !(v24_sig & RFCOMM_V24_DV))
+ tty_port_tty_hangup(&dev->port, true);
dev->modem_status =
((v24_sig & RFCOMM_V24_RTC) ? (TIOCM_DSR | TIOCM_DTR) : 0) |
@@ -638,124 +655,92 @@ static void rfcomm_tty_copy_pending(struct rfcomm_dev *dev)
tty_flip_buffer_push(&dev->port);
}
-static int rfcomm_tty_open(struct tty_struct *tty, struct file *filp)
+/* do the reverse of install, clearing the tty fields and releasing the
+ * reference to tty_port
+ */
+static void rfcomm_tty_cleanup(struct tty_struct *tty)
{
- DECLARE_WAITQUEUE(wait, current);
- struct rfcomm_dev *dev;
- struct rfcomm_dlc *dlc;
- unsigned long flags;
- int err, id;
+ struct rfcomm_dev *dev = tty->driver_data;
- id = tty->index;
+ clear_bit(RFCOMM_TTY_ATTACHED, &dev->flags);
- BT_DBG("tty %p id %d", tty, id);
+ rfcomm_dlc_lock(dev->dlc);
+ tty->driver_data = NULL;
+ rfcomm_dlc_unlock(dev->dlc);
- /* We don't leak this refcount. For reasons which are not entirely
- clear, the TTY layer will call our ->close() method even if the
- open fails. We decrease the refcount there, and decreasing it
- here too would cause breakage. */
- dev = rfcomm_dev_get(id);
- if (!dev)
- return -ENODEV;
+ /*
+ * purge the dlc->tx_queue to avoid circular dependencies
+ * between dev and dlc
+ */
+ skb_queue_purge(&dev->dlc->tx_queue);
- BT_DBG("dev %p dst %pMR channel %d opened %d", dev, &dev->dst,
- dev->channel, dev->port.count);
+ tty_port_put(&dev->port);
+}
- spin_lock_irqsave(&dev->port.lock, flags);
- if (++dev->port.count > 1) {
- spin_unlock_irqrestore(&dev->port.lock, flags);
- return 0;
- }
- spin_unlock_irqrestore(&dev->port.lock, flags);
+/* we acquire the tty_port reference since it's here the tty is first used
+ * by setting the termios. We also populate the driver_data field and install
+ * the tty port
+ */
+static int rfcomm_tty_install(struct tty_driver *driver, struct tty_struct *tty)
+{
+ struct rfcomm_dev *dev;
+ struct rfcomm_dlc *dlc;
+ int err;
+
+ dev = rfcomm_dev_get(tty->index);
+ if (!dev)
+ return -ENODEV;
dlc = dev->dlc;
/* Attach TTY and open DLC */
-
rfcomm_dlc_lock(dlc);
tty->driver_data = dev;
- dev->port.tty = tty;
rfcomm_dlc_unlock(dlc);
set_bit(RFCOMM_TTY_ATTACHED, &dev->flags);
- err = rfcomm_dlc_open(dlc, &dev->src, &dev->dst, dev->channel);
- if (err < 0)
- return err;
-
- /* Wait for DLC to connect */
- add_wait_queue(&dev->wait, &wait);
- while (1) {
- set_current_state(TASK_INTERRUPTIBLE);
+ /* install the tty_port */
+ err = tty_port_install(&dev->port, driver, tty);
+ if (err)
+ rfcomm_tty_cleanup(tty);
- if (dlc->state == BT_CLOSED) {
- err = -dev->err;
- break;
- }
+ return err;
+}
- if (dlc->state == BT_CONNECTED)
- break;
+static int rfcomm_tty_open(struct tty_struct *tty, struct file *filp)
+{
+ struct rfcomm_dev *dev = tty->driver_data;
+ int err;
- if (signal_pending(current)) {
- err = -EINTR;
- break;
- }
+ BT_DBG("tty %p id %d", tty, tty->index);
- tty_unlock(tty);
- schedule();
- tty_lock(tty);
- }
- set_current_state(TASK_RUNNING);
- remove_wait_queue(&dev->wait, &wait);
+ BT_DBG("dev %p dst %pMR channel %d opened %d", dev, &dev->dst,
+ dev->channel, dev->port.count);
- if (err == 0)
- device_move(dev->tty_dev, rfcomm_get_device(dev),
- DPM_ORDER_DEV_AFTER_PARENT);
+ err = tty_port_open(&dev->port, tty, filp);
+ if (err)
+ return err;
+ /*
+ * FIXME: rfcomm should use proper flow control for
+ * received data. This hack will be unnecessary and can
+ * be removed when that's implemented
+ */
rfcomm_tty_copy_pending(dev);
rfcomm_dlc_unthrottle(dev->dlc);
- return err;
+ return 0;
}
static void rfcomm_tty_close(struct tty_struct *tty, struct file *filp)
{
struct rfcomm_dev *dev = (struct rfcomm_dev *) tty->driver_data;
- unsigned long flags;
-
- if (!dev)
- return;
BT_DBG("tty %p dev %p dlc %p opened %d", tty, dev, dev->dlc,
dev->port.count);
- spin_lock_irqsave(&dev->port.lock, flags);
- if (!--dev->port.count) {
- spin_unlock_irqrestore(&dev->port.lock, flags);
- if (dev->tty_dev->parent)
- device_move(dev->tty_dev, NULL, DPM_ORDER_DEV_LAST);
-
- /* Close DLC and dettach TTY */
- rfcomm_dlc_close(dev->dlc, 0);
-
- clear_bit(RFCOMM_TTY_ATTACHED, &dev->flags);
-
- rfcomm_dlc_lock(dev->dlc);
- tty->driver_data = NULL;
- dev->port.tty = NULL;
- rfcomm_dlc_unlock(dev->dlc);
-
- if (test_bit(RFCOMM_TTY_RELEASED, &dev->flags)) {
- spin_lock(&rfcomm_dev_lock);
- list_del_init(&dev->list);
- spin_unlock(&rfcomm_dev_lock);
-
- tty_port_put(&dev->port);
- }
- } else
- spin_unlock_irqrestore(&dev->port.lock, flags);
-
- tty_port_put(&dev->port);
+ tty_port_close(&dev->port, tty, filp);
}
static int rfcomm_tty_write(struct tty_struct *tty, const unsigned char *buf, int count)
@@ -1055,17 +1040,11 @@ static void rfcomm_tty_hangup(struct tty_struct *tty)
BT_DBG("tty %p dev %p", tty, dev);
- if (!dev)
- return;
-
- rfcomm_tty_flush_buffer(tty);
+ tty_port_hangup(&dev->port);
- if (test_bit(RFCOMM_RELEASE_ONHUP, &dev->flags)) {
- if (rfcomm_dev_get(dev->id) == NULL)
- return;
- rfcomm_dev_del(dev);
+ if (test_bit(RFCOMM_RELEASE_ONHUP, &dev->flags) &&
+ !test_and_set_bit(RFCOMM_TTY_RELEASED, &dev->flags))
tty_port_put(&dev->port);
- }
}
static int rfcomm_tty_tiocmget(struct tty_struct *tty)
@@ -1128,6 +1107,8 @@ static const struct tty_operations rfcomm_ops = {
.wait_until_sent = rfcomm_tty_wait_until_sent,
.tiocmget = rfcomm_tty_tiocmget,
.tiocmset = rfcomm_tty_tiocmset,
+ .install = rfcomm_tty_install,
+ .cleanup = rfcomm_tty_cleanup,
};
int __init rfcomm_init_ttys(void)
@@ -1146,7 +1127,7 @@ int __init rfcomm_init_ttys(void)
rfcomm_tty_driver->subtype = SERIAL_TYPE_NORMAL;
rfcomm_tty_driver->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV;
rfcomm_tty_driver->init_termios = tty_std_termios;
- rfcomm_tty_driver->init_termios.c_cflag = B9600 | CS8 | CREAD | HUPCL | CLOCAL;
+ rfcomm_tty_driver->init_termios.c_cflag = B9600 | CS8 | CREAD | HUPCL;
rfcomm_tty_driver->init_termios.c_lflag &= ~ICANON;
tty_set_operations(rfcomm_tty_driver, &rfcomm_ops);