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-rw-r--r--drivers/tty/Makefile2
-rw-r--r--drivers/tty/n_tty.c12
-rw-r--r--drivers/tty/serial/altera_uart.c1
-rw-r--r--drivers/tty/serial/amba-pl011.c11
-rw-r--r--drivers/tty/serial/imx.c15
-rw-r--r--drivers/tty/serial/mpc52xx_uart.c10
-rw-r--r--drivers/tty/serial/omap-serial.c34
-rw-r--r--drivers/tty/serial/serial_core.c6
-rw-r--r--drivers/tty/serial/xilinx_uartps.c30
-rw-r--r--drivers/tty/tty_ldsem.c453
-rw-r--r--drivers/tty/vt/vt.c117
11 files changed, 525 insertions, 166 deletions
diff --git a/drivers/tty/Makefile b/drivers/tty/Makefile
index 6b78399bc7c9..58ad1c05b7f8 100644
--- a/drivers/tty/Makefile
+++ b/drivers/tty/Makefile
@@ -1,5 +1,5 @@
obj-$(CONFIG_TTY) += tty_io.o n_tty.o tty_ioctl.o tty_ldisc.o \
- tty_buffer.o tty_port.o tty_mutex.o
+ tty_buffer.o tty_port.o tty_mutex.o tty_ldsem.o
obj-$(CONFIG_LEGACY_PTYS) += pty.o
obj-$(CONFIG_UNIX98_PTYS) += pty.o
obj-$(CONFIG_AUDIT) += tty_audit.o
diff --git a/drivers/tty/n_tty.c b/drivers/tty/n_tty.c
index 6c7fe90ad72d..cdcdb0ea061a 100644
--- a/drivers/tty/n_tty.c
+++ b/drivers/tty/n_tty.c
@@ -647,8 +647,7 @@ static void process_echoes(struct tty_struct *tty)
if (no_space_left)
break;
} else {
- if (O_OPOST(tty) &&
- !(test_bit(TTY_HW_COOK_OUT, &tty->flags))) {
+ if (O_OPOST(tty)) {
int retval = do_output_char(c, tty, space);
if (retval < 0)
break;
@@ -1516,12 +1515,7 @@ static void n_tty_set_termios(struct tty_struct *tty, struct ktermios *old)
wake_up_interruptible(&tty->read_wait);
ldata->icanon = (L_ICANON(tty) != 0);
- if (test_bit(TTY_HW_COOK_IN, &tty->flags)) {
- ldata->raw = 1;
- ldata->real_raw = 1;
- n_tty_set_room(tty);
- return;
- }
+
if (I_ISTRIP(tty) || I_IUCLC(tty) || I_IGNCR(tty) ||
I_ICRNL(tty) || I_INLCR(tty) || L_ICANON(tty) ||
I_IXON(tty) || L_ISIG(tty) || L_ECHO(tty) ||
@@ -2045,7 +2039,7 @@ static ssize_t n_tty_write(struct tty_struct *tty, struct file *file,
retval = -EIO;
break;
}
- if (O_OPOST(tty) && !(test_bit(TTY_HW_COOK_OUT, &tty->flags))) {
+ if (O_OPOST(tty)) {
while (nr > 0) {
ssize_t num = process_output_block(tty, b, nr);
if (num < 0) {
diff --git a/drivers/tty/serial/altera_uart.c b/drivers/tty/serial/altera_uart.c
index 13471dd95793..1d46966e2a65 100644
--- a/drivers/tty/serial/altera_uart.c
+++ b/drivers/tty/serial/altera_uart.c
@@ -604,7 +604,6 @@ static int altera_uart_remove(struct platform_device *pdev)
if (port) {
uart_remove_one_port(&altera_uart_driver, port);
- platform_set_drvdata(pdev, NULL);
port->mapbase = 0;
}
diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c
index e2774f9ecd59..ad41319d1d9b 100644
--- a/drivers/tty/serial/amba-pl011.c
+++ b/drivers/tty/serial/amba-pl011.c
@@ -79,13 +79,12 @@ struct vendor_data {
bool dma_threshold;
bool cts_event_workaround;
- unsigned int (*get_fifosize)(unsigned int periphid);
+ unsigned int (*get_fifosize)(struct amba_device *dev);
};
-static unsigned int get_fifosize_arm(unsigned int periphid)
+static unsigned int get_fifosize_arm(struct amba_device *dev)
{
- unsigned int rev = (periphid >> 20) & 0xf;
- return rev < 3 ? 16 : 32;
+ return amba_rev(dev) < 3 ? 16 : 32;
}
static struct vendor_data vendor_arm = {
@@ -98,7 +97,7 @@ static struct vendor_data vendor_arm = {
.get_fifosize = get_fifosize_arm,
};
-static unsigned int get_fifosize_st(unsigned int periphid)
+static unsigned int get_fifosize_st(struct amba_device *dev)
{
return 64;
}
@@ -2157,7 +2156,7 @@ static int pl011_probe(struct amba_device *dev, const struct amba_id *id)
uap->lcrh_rx = vendor->lcrh_rx;
uap->lcrh_tx = vendor->lcrh_tx;
uap->old_cr = 0;
- uap->fifosize = vendor->get_fifosize(dev->periphid);
+ uap->fifosize = vendor->get_fifosize(dev);
uap->port.dev = &dev->dev;
uap->port.mapbase = dev->res.start;
uap->port.membase = base;
diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c
index 147c9e193595..72bc1dbcd055 100644
--- a/drivers/tty/serial/imx.c
+++ b/drivers/tty/serial/imx.c
@@ -449,6 +449,13 @@ static void imx_start_tx(struct uart_port *port)
temp &= ~(UCR1_RRDYEN);
writel(temp, sport->port.membase + UCR1);
}
+ /* Clear any pending ORE flag before enabling interrupt */
+ temp = readl(sport->port.membase + USR2);
+ writel(temp | USR2_ORE, sport->port.membase + USR2);
+
+ temp = readl(sport->port.membase + UCR4);
+ temp |= UCR4_OREN;
+ writel(temp, sport->port.membase + UCR4);
temp = readl(sport->port.membase + UCR1);
writel(temp | UCR1_TXMPTYEN, sport->port.membase + UCR1);
@@ -582,6 +589,7 @@ static irqreturn_t imx_int(int irq, void *dev_id)
{
struct imx_port *sport = dev_id;
unsigned int sts;
+ unsigned int sts2;
sts = readl(sport->port.membase + USR1);
@@ -598,6 +606,13 @@ static irqreturn_t imx_int(int irq, void *dev_id)
if (sts & USR1_AWAKE)
writel(USR1_AWAKE, sport->port.membase + USR1);
+ sts2 = readl(sport->port.membase + USR2);
+ if (sts2 & USR2_ORE) {
+ dev_err(sport->port.dev, "Rx FIFO overrun\n");
+ sport->port.icount.overrun++;
+ writel(sts2 | USR2_ORE, sport->port.membase + USR2);
+ }
+
return IRQ_HANDLED;
}
diff --git a/drivers/tty/serial/mpc52xx_uart.c b/drivers/tty/serial/mpc52xx_uart.c
index f51b280f3bf2..510fa986cf9e 100644
--- a/drivers/tty/serial/mpc52xx_uart.c
+++ b/drivers/tty/serial/mpc52xx_uart.c
@@ -84,16 +84,6 @@ static void mpc52xx_uart_of_enumerate(void);
static irqreturn_t mpc52xx_uart_int(int irq, void *dev_id);
static irqreturn_t mpc5xxx_uart_process_int(struct uart_port *port);
-
-/* Simple macro to test if a port is console or not. This one is taken
- * for serial_core.c and maybe should be moved to serial_core.h ? */
-#ifdef CONFIG_SERIAL_CORE_CONSOLE
-#define uart_console(port) \
- ((port)->cons && (port)->cons->index == (port)->line)
-#else
-#define uart_console(port) (0)
-#endif
-
/* ======================================================================== */
/* PSC fifo operations for isolating differences between 52xx and 512x */
/* ======================================================================== */
diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-serial.c
index f0b9f6b52b32..393a8eb98d72 100644
--- a/drivers/tty/serial/omap-serial.c
+++ b/drivers/tty/serial/omap-serial.c
@@ -161,6 +161,7 @@ struct uart_omap_port {
u32 calc_latency;
struct work_struct qos_work;
struct pinctrl *pins;
+ bool is_suspending;
};
#define to_uart_omap_port(p) ((container_of((p), struct uart_omap_port, port)))
@@ -1289,6 +1290,22 @@ static struct uart_driver serial_omap_reg = {
};
#ifdef CONFIG_PM_SLEEP
+static int serial_omap_prepare(struct device *dev)
+{
+ struct uart_omap_port *up = dev_get_drvdata(dev);
+
+ up->is_suspending = true;
+
+ return 0;
+}
+
+static void serial_omap_complete(struct device *dev)
+{
+ struct uart_omap_port *up = dev_get_drvdata(dev);
+
+ up->is_suspending = false;
+}
+
static int serial_omap_suspend(struct device *dev)
{
struct uart_omap_port *up = dev_get_drvdata(dev);
@@ -1307,7 +1324,10 @@ static int serial_omap_resume(struct device *dev)
return 0;
}
-#endif
+#else
+#define serial_omap_prepare NULL
+#define serial_omap_prepare NULL
+#endif /* CONFIG_PM_SLEEP */
static void omap_serial_fill_features_erratas(struct uart_omap_port *up)
{
@@ -1593,6 +1613,16 @@ static int serial_omap_runtime_suspend(struct device *dev)
struct uart_omap_port *up = dev_get_drvdata(dev);
struct omap_uart_port_info *pdata = dev->platform_data;
+ /*
+ * When using 'no_console_suspend', the console UART must not be
+ * suspended. Since driver suspend is managed by runtime suspend,
+ * preventing runtime suspend (by returning error) will keep device
+ * active during suspend.
+ */
+ if (up->is_suspending && !console_suspend_enabled &&
+ uart_console(&up->port))
+ return -EBUSY;
+
if (!up)
return -EINVAL;
@@ -1643,6 +1673,8 @@ static const struct dev_pm_ops serial_omap_dev_pm_ops = {
SET_SYSTEM_SLEEP_PM_OPS(serial_omap_suspend, serial_omap_resume)
SET_RUNTIME_PM_OPS(serial_omap_runtime_suspend,
serial_omap_runtime_resume, NULL)
+ .prepare = serial_omap_prepare,
+ .complete = serial_omap_complete,
};
#if defined(CONFIG_OF)
diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c
index f87dbfd32770..28cdd2829139 100644
--- a/drivers/tty/serial/serial_core.c
+++ b/drivers/tty/serial/serial_core.c
@@ -50,12 +50,6 @@ static struct lock_class_key port_lock_key;
#define HIGH_BITS_OFFSET ((sizeof(long)-sizeof(int))*8)
-#ifdef CONFIG_SERIAL_CORE_CONSOLE
-#define uart_console(port) ((port)->cons && (port)->cons->index == (port)->line)
-#else
-#define uart_console(port) (0)
-#endif
-
static void uart_change_speed(struct tty_struct *tty, struct uart_state *state,
struct ktermios *old_termios);
static void uart_wait_until_sent(struct tty_struct *tty, int timeout);
diff --git a/drivers/tty/serial/xilinx_uartps.c b/drivers/tty/serial/xilinx_uartps.c
index 4e5c77834c50..b5f655d10098 100644
--- a/drivers/tty/serial/xilinx_uartps.c
+++ b/drivers/tty/serial/xilinx_uartps.c
@@ -1006,34 +1006,6 @@ static int xuartps_remove(struct platform_device *pdev)
return rc;
}
-/**
- * xuartps_suspend - suspend event
- * @pdev: Pointer to the platform device structure
- * @state: State of the device
- *
- * Returns 0
- **/
-static int xuartps_suspend(struct platform_device *pdev, pm_message_t state)
-{
- /* Call the API provided in serial_core.c file which handles
- * the suspend.
- */
- uart_suspend_port(&xuartps_uart_driver, &xuartps_port[pdev->id]);
- return 0;
-}
-
-/**
- * xuartps_resume - Resume after a previous suspend
- * @pdev: Pointer to the platform device structure
- *
- * Returns 0
- **/
-static int xuartps_resume(struct platform_device *pdev)
-{
- uart_resume_port(&xuartps_uart_driver, &xuartps_port[pdev->id]);
- return 0;
-}
-
/* Match table for of_platform binding */
static struct of_device_id xuartps_of_match[] = {
{ .compatible = "xlnx,xuartps", },
@@ -1044,8 +1016,6 @@ MODULE_DEVICE_TABLE(of, xuartps_of_match);
static struct platform_driver xuartps_platform_driver = {
.probe = xuartps_probe, /* Probe method */
.remove = xuartps_remove, /* Detach method */
- .suspend = xuartps_suspend, /* Suspend */
- .resume = xuartps_resume, /* Resume after a suspend */
.driver = {
.owner = THIS_MODULE,
.name = XUARTPS_NAME, /* Driver name */
diff --git a/drivers/tty/tty_ldsem.c b/drivers/tty/tty_ldsem.c
new file mode 100644
index 000000000000..22fad8ad5ac2
--- /dev/null
+++ b/drivers/tty/tty_ldsem.c
@@ -0,0 +1,453 @@
+/*
+ * Ldisc rw semaphore
+ *
+ * The ldisc semaphore is semantically a rw_semaphore but which enforces
+ * an alternate policy, namely:
+ * 1) Supports lock wait timeouts
+ * 2) Write waiter has priority
+ * 3) Downgrading is not supported
+ *
+ * Implementation notes:
+ * 1) Upper half of semaphore count is a wait count (differs from rwsem
+ * in that rwsem normalizes the upper half to the wait bias)
+ * 2) Lacks overflow checking
+ *
+ * The generic counting was copied and modified from include/asm-generic/rwsem.h
+ * by Paul Mackerras <paulus@samba.org>.
+ *
+ * The scheduling policy was copied and modified from lib/rwsem.c
+ * Written by David Howells (dhowells@redhat.com).
+ *
+ * This implementation incorporates the write lock stealing work of
+ * Michel Lespinasse <walken@google.com>.
+ *
+ * Copyright (C) 2013 Peter Hurley <peter@hurleysoftware.com>
+ *
+ * This file may be redistributed under the terms of the GNU General Public
+ * License v2.
+ */
+
+#include <linux/list.h>
+#include <linux/spinlock.h>
+#include <linux/atomic.h>
+#include <linux/tty.h>
+#include <linux/sched.h>
+
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+# define __acq(l, s, t, r, c, n, i) \
+ lock_acquire(&(l)->dep_map, s, t, r, c, n, i)
+# define __rel(l, n, i) \
+ lock_release(&(l)->dep_map, n, i)
+# ifdef CONFIG_PROVE_LOCKING
+# define lockdep_acquire(l, s, t, i) __acq(l, s, t, 0, 2, NULL, i)
+# define lockdep_acquire_nest(l, s, t, n, i) __acq(l, s, t, 0, 2, n, i)
+# define lockdep_acquire_read(l, s, t, i) __acq(l, s, t, 1, 2, NULL, i)
+# define lockdep_release(l, n, i) __rel(l, n, i)
+# else
+# define lockdep_acquire(l, s, t, i) __acq(l, s, t, 0, 1, NULL, i)
+# define lockdep_acquire_nest(l, s, t, n, i) __acq(l, s, t, 0, 1, n, i)
+# define lockdep_acquire_read(l, s, t, i) __acq(l, s, t, 1, 1, NULL, i)
+# define lockdep_release(l, n, i) __rel(l, n, i)
+# endif
+#else
+# define lockdep_acquire(l, s, t, i) do { } while (0)
+# define lockdep_acquire_nest(l, s, t, n, i) do { } while (0)
+# define lockdep_acquire_read(l, s, t, i) do { } while (0)
+# define lockdep_release(l, n, i) do { } while (0)
+#endif
+
+#ifdef CONFIG_LOCK_STAT
+# define lock_stat(_lock, stat) lock_##stat(&(_lock)->dep_map, _RET_IP_)
+#else
+# define lock_stat(_lock, stat) do { } while (0)
+#endif
+
+
+#if BITS_PER_LONG == 64
+# define LDSEM_ACTIVE_MASK 0xffffffffL
+#else
+# define LDSEM_ACTIVE_MASK 0x0000ffffL
+#endif
+
+#define LDSEM_UNLOCKED 0L
+#define LDSEM_ACTIVE_BIAS 1L
+#define LDSEM_WAIT_BIAS (-LDSEM_ACTIVE_MASK-1)
+#define LDSEM_READ_BIAS LDSEM_ACTIVE_BIAS
+#define LDSEM_WRITE_BIAS (LDSEM_WAIT_BIAS + LDSEM_ACTIVE_BIAS)
+
+struct ldsem_waiter {
+ struct list_head list;
+ struct task_struct *task;
+};
+
+static inline long ldsem_atomic_update(long delta, struct ld_semaphore *sem)
+{
+ return atomic_long_add_return(delta, (atomic_long_t *)&sem->count);
+}
+
+static inline int ldsem_cmpxchg(long *old, long new, struct ld_semaphore *sem)
+{
+ long tmp = *old;
+ *old = atomic_long_cmpxchg(&sem->count, *old, new);
+ return *old == tmp;
+}
+
+/*
+ * Initialize an ldsem:
+ */
+void __init_ldsem(struct ld_semaphore *sem, const char *name,
+ struct lock_class_key *key)
+{
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+ /*
+ * Make sure we are not reinitializing a held semaphore:
+ */
+ debug_check_no_locks_freed((void *)sem, sizeof(*sem));
+ lockdep_init_map(&sem->dep_map, name, key, 0);
+#endif
+ sem->count = LDSEM_UNLOCKED;
+ sem->wait_readers = 0;
+ raw_spin_lock_init(&sem->wait_lock);
+ INIT_LIST_HEAD(&sem->read_wait);
+ INIT_LIST_HEAD(&sem->write_wait);
+}
+
+static void __ldsem_wake_readers(struct ld_semaphore *sem)
+{
+ struct ldsem_waiter *waiter, *next;
+ struct task_struct *tsk;
+ long adjust, count;
+
+ /* Try to grant read locks to all readers on the read wait list.
+ * Note the 'active part' of the count is incremented by
+ * the number of readers before waking any processes up.
+ */
+ adjust = sem->wait_readers * (LDSEM_ACTIVE_BIAS - LDSEM_WAIT_BIAS);
+ count = ldsem_atomic_update(adjust, sem);
+ do {
+ if (count > 0)
+ break;
+ if (ldsem_cmpxchg(&count, count - adjust, sem))
+ return;
+ } while (1);
+
+ list_for_each_entry_safe(waiter, next, &sem->read_wait, list) {
+ tsk = waiter->task;
+ smp_mb();
+ waiter->task = NULL;
+ wake_up_process(tsk);
+ put_task_struct(tsk);
+ }
+ INIT_LIST_HEAD(&sem->read_wait);
+ sem->wait_readers = 0;
+}
+
+static inline int writer_trylock(struct ld_semaphore *sem)
+{
+ /* only wake this writer if the active part of the count can be
+ * transitioned from 0 -> 1
+ */
+ long count = ldsem_atomic_update(LDSEM_ACTIVE_BIAS, sem);
+ do {
+ if ((count & LDSEM_ACTIVE_MASK) == LDSEM_ACTIVE_BIAS)
+ return 1;
+ if (ldsem_cmpxchg(&count, count - LDSEM_ACTIVE_BIAS, sem))
+ return 0;
+ } while (1);
+}
+
+static void __ldsem_wake_writer(struct ld_semaphore *sem)
+{
+ struct ldsem_waiter *waiter;
+
+ waiter = list_entry(sem->write_wait.next, struct ldsem_waiter, list);
+ wake_up_process(waiter->task);
+}
+
+/*
+ * handle the lock release when processes blocked on it that can now run
+ * - if we come here from up_xxxx(), then:
+ * - the 'active part' of count (&0x0000ffff) reached 0 (but may have changed)
+ * - the 'waiting part' of count (&0xffff0000) is -ve (and will still be so)
+ * - the spinlock must be held by the caller
+ * - woken process blocks are discarded from the list after having task zeroed
+ */
+static void __ldsem_wake(struct ld_semaphore *sem)
+{
+ if (!list_empty(&sem->write_wait))
+ __ldsem_wake_writer(sem);
+ else if (!list_empty(&sem->read_wait))
+ __ldsem_wake_readers(sem);
+}
+
+static void ldsem_wake(struct ld_semaphore *sem)
+{
+ unsigned long flags;
+
+ raw_spin_lock_irqsave(&sem->wait_lock, flags);
+ __ldsem_wake(sem);
+ raw_spin_unlock_irqrestore(&sem->wait_lock, flags);
+}
+
+/*
+ * wait for the read lock to be granted
+ */
+static struct ld_semaphore __sched *
+down_read_failed(struct ld_semaphore *sem, long count, long timeout)
+{
+ struct ldsem_waiter waiter;
+ struct task_struct *tsk = current;
+ long adjust = -LDSEM_ACTIVE_BIAS + LDSEM_WAIT_BIAS;
+
+ /* set up my own style of waitqueue */
+ raw_spin_lock_irq(&sem->wait_lock);
+
+ /* Try to reverse the lock attempt but if the count has changed
+ * so that reversing fails, check if there are are no waiters,
+ * and early-out if not */
+ do {
+ if (ldsem_cmpxchg(&count, count + adjust, sem))
+ break;
+ if (count > 0) {
+ raw_spin_unlock_irq(&sem->wait_lock);
+ return sem;
+ }
+ } while (1);
+
+ list_add_tail(&waiter.list, &sem->read_wait);
+ sem->wait_readers++;
+
+ waiter.task = tsk;
+ get_task_struct(tsk);
+
+ /* if there are no active locks, wake the new lock owner(s) */
+ if ((count & LDSEM_ACTIVE_MASK) == 0)
+ __ldsem_wake(sem);
+
+ raw_spin_unlock_irq(&sem->wait_lock);
+
+ /* wait to be given the lock */
+ for (;;) {
+ set_task_state(tsk, TASK_UNINTERRUPTIBLE);
+
+ if (!waiter.task)
+ break;
+ if (!timeout)
+ break;
+ timeout = schedule_timeout(timeout);
+ }
+
+ __set_task_state(tsk, TASK_RUNNING);
+
+ if (!timeout) {
+ /* lock timed out but check if this task was just
+ * granted lock ownership - if so, pretend there
+ * was no timeout; otherwise, cleanup lock wait */
+ raw_spin_lock_irq(&sem->wait_lock);
+ if (waiter.task) {
+ ldsem_atomic_update(-LDSEM_WAIT_BIAS, sem);
+ list_del(&waiter.list);
+ raw_spin_unlock_irq(&sem->wait_lock);
+ put_task_struct(waiter.task);
+ return NULL;
+ }
+ raw_spin_unlock_irq(&sem->wait_lock);
+ }
+
+ return sem;
+}
+
+/*
+ * wait for the write lock to be granted
+ */
+static struct ld_semaphore __sched *
+down_write_failed(struct ld_semaphore *sem, long count, long timeout)
+{
+ struct ldsem_waiter waiter;
+ struct task_struct *tsk = current;
+ long adjust = -LDSEM_ACTIVE_BIAS;
+ int locked = 0;
+
+ /* set up my own style of waitqueue */
+ raw_spin_lock_irq(&sem->wait_lock);
+
+ /* Try to reverse the lock attempt but if the count has changed
+ * so that reversing fails, check if the lock is now owned,
+ * and early-out if so */
+ do {
+ if (ldsem_cmpxchg(&count, count + adjust, sem))
+ break;
+ if ((count & LDSEM_ACTIVE_MASK) == LDSEM_ACTIVE_BIAS) {
+ raw_spin_unlock_irq(&sem->wait_lock);
+ return sem;
+ }
+ } while (1);
+
+ list_add_tail(&waiter.list, &sem->write_wait);
+
+ waiter.task = tsk;
+
+ set_task_state(tsk, TASK_UNINTERRUPTIBLE);
+ for (;;) {
+ if (!timeout)
+ break;
+ raw_spin_unlock_irq(&sem->wait_lock);
+ timeout = schedule_timeout(timeout);
+ raw_spin_lock_irq(&sem->wait_lock);
+ set_task_state(tsk, TASK_UNINTERRUPTIBLE);
+ if ((locked = writer_trylock(sem)))
+ break;
+ }
+
+ if (!locked)
+ ldsem_atomic_update(-LDSEM_WAIT_BIAS, sem);
+ list_del(&waiter.list);
+ raw_spin_unlock_irq(&sem->wait_lock);
+
+ __set_task_state(tsk, TASK_RUNNING);
+
+ /* lock wait may have timed out */
+ if (!locked)
+ return NULL;
+ return sem;
+}
+
+
+
+static inline int __ldsem_down_read_nested(struct ld_semaphore *sem,
+ int subclass, long timeout)
+{
+ long count;
+
+ lockdep_acquire_read(sem, subclass, 0, _RET_IP_);
+
+ count = ldsem_atomic_update(LDSEM_READ_BIAS, sem);
+ if (count <= 0) {
+ lock_stat(sem, contended);
+ if (!down_read_failed(sem, count, timeout)) {
+ lockdep_release(sem, 1, _RET_IP_);
+ return 0;
+ }
+ }
+ lock_stat(sem, acquired);
+ return 1;
+}
+
+static inline int __ldsem_down_write_nested(struct ld_semaphore *sem,
+ int subclass, long timeout)
+{
+ long count;
+
+ lockdep_acquire(sem, subclass, 0, _RET_IP_);
+
+ count = ldsem_atomic_update(LDSEM_WRITE_BIAS, sem);
+ if ((count & LDSEM_ACTIVE_MASK) != LDSEM_ACTIVE_BIAS) {
+ lock_stat(sem, contended);
+ if (!down_write_failed(sem, count, timeout)) {
+ lockdep_release(sem, 1, _RET_IP_);
+ return 0;
+ }
+ }
+ lock_stat(sem, acquired);
+ return 1;
+}
+
+
+/*
+ * lock for reading -- returns 1 if successful, 0 if timed out
+ */
+int __sched ldsem_down_read(struct ld_semaphore *sem, long timeout)
+{
+ might_sleep();
+ return __ldsem_down_read_nested(sem, 0, timeout);
+}
+
+/*
+ * trylock for reading -- returns 1 if successful, 0 if contention
+ */
+int ldsem_down_read_trylock(struct ld_semaphore *sem)
+{
+ long count = sem->count;
+
+ while (count >= 0) {
+ if (ldsem_cmpxchg(&count, count + LDSEM_READ_BIAS, sem)) {
+ lockdep_acquire_read(sem, 0, 1, _RET_IP_);
+ lock_stat(sem, acquired);
+ return 1;
+ }
+ }
+ return 0;
+}
+
+/*
+ * lock for writing -- returns 1 if successful, 0 if timed out
+ */
+int __sched ldsem_down_write(struct ld_semaphore *sem, long timeout)
+{
+ might_sleep();
+ return __ldsem_down_write_nested(sem, 0, timeout);
+}
+
+/*
+ * trylock for writing -- returns 1 if successful, 0 if contention
+ */
+int ldsem_down_write_trylock(struct ld_semaphore *sem)
+{
+ long count = sem->count;
+
+ while ((count & LDSEM_ACTIVE_MASK) == 0) {
+ if (ldsem_cmpxchg(&count, count + LDSEM_WRITE_BIAS, sem)) {
+ lockdep_acquire(sem, 0, 1, _RET_IP_);
+ lock_stat(sem, acquired);
+ return 1;
+ }
+ }
+ return 0;
+}
+
+/*
+ * release a read lock
+ */
+void ldsem_up_read(struct ld_semaphore *sem)
+{
+ long count;
+
+ lockdep_release(sem, 1, _RET_IP_);
+
+ count = ldsem_atomic_update(-LDSEM_READ_BIAS, sem);
+ if (count < 0 && (count & LDSEM_ACTIVE_MASK) == 0)
+ ldsem_wake(sem);
+}
+
+/*
+ * release a write lock
+ */
+void ldsem_up_write(struct ld_semaphore *sem)
+{
+ long count;
+
+ lockdep_release(sem, 1, _RET_IP_);
+
+ count = ldsem_atomic_update(-LDSEM_WRITE_BIAS, sem);
+ if (count < 0)
+ ldsem_wake(sem);
+}
+
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+
+int ldsem_down_read_nested(struct ld_semaphore *sem, int subclass, long timeout)
+{
+ might_sleep();
+ return __ldsem_down_read_nested(sem, subclass, timeout);
+}
+
+int ldsem_down_write_nested(struct ld_semaphore *sem, int subclass,
+ long timeout)
+{
+ might_sleep();
+ return __ldsem_down_write_nested(sem, subclass, timeout);
+}
+
+#endif
diff --git a/drivers/tty/vt/vt.c b/drivers/tty/vt/vt.c
index 740202d8a5c4..c677829baa8b 100644
--- a/drivers/tty/vt/vt.c
+++ b/drivers/tty/vt/vt.c
@@ -3086,17 +3086,6 @@ err:
};
-static int bind_con_driver(const struct consw *csw, int first, int last,
- int deflt)
-{
- int ret;
-
- console_lock();
- ret = do_bind_con_driver(csw, first, last, deflt);
- console_unlock();
- return ret;
-}
-
#ifdef CONFIG_VT_HW_CONSOLE_BINDING
static int con_is_graphics(const struct consw *csw, int first, int last)
{
@@ -3114,34 +3103,6 @@ static int con_is_graphics(const struct consw *csw, int first, int last)
return retval;
}
-/**
- * unbind_con_driver - unbind a console driver
- * @csw: pointer to console driver to unregister
- * @first: first in range of consoles that @csw should be unbound from
- * @last: last in range of consoles that @csw should be unbound from
- * @deflt: should next bound console driver be default after @csw is unbound?
- *
- * To unbind a driver from all possible consoles, pass 0 as @first and
- * %MAX_NR_CONSOLES as @last.
- *
- * @deflt controls whether the console that ends up replacing @csw should be
- * the default console.
- *
- * RETURNS:
- * -ENODEV if @csw isn't a registered console driver or can't be unregistered
- * or 0 on success.
- */
-int unbind_con_driver(const struct consw *csw, int first, int last, int deflt)
-{
- int retval;
-
- console_lock();
- retval = do_unbind_con_driver(csw, first, last, deflt);
- console_unlock();
- return retval;
-}
-EXPORT_SYMBOL(unbind_con_driver);
-
/* unlocked version of unbind_con_driver() */
int do_unbind_con_driver(const struct consw *csw, int first, int last, int deflt)
{
@@ -3262,8 +3223,11 @@ static int vt_bind(struct con_driver *con)
if (first == 0 && last == MAX_NR_CONSOLES -1)
deflt = 1;
- if (first != -1)
- bind_con_driver(csw, first, last, deflt);
+ if (first != -1) {
+ console_lock();
+ do_bind_con_driver(csw, first, last, deflt);
+ console_unlock();
+ }
first = -1;
last = -1;
@@ -3301,8 +3265,11 @@ static int vt_unbind(struct con_driver *con)
if (first == 0 && last == MAX_NR_CONSOLES -1)
deflt = 1;
- if (first != -1)
- unbind_con_driver(csw, first, last, deflt);
+ if (first != -1) {
+ console_lock();
+ do_unbind_con_driver(csw, first, last, deflt);
+ console_unlock();
+ }
first = -1;
last = -1;
@@ -3574,29 +3541,9 @@ err:
return retval;
}
-/**
- * register_con_driver - register console driver to console layer
- * @csw: console driver
- * @first: the first console to take over, minimum value is 0
- * @last: the last console to take over, maximum value is MAX_NR_CONSOLES -1
- *
- * DESCRIPTION: This function registers a console driver which can later
- * bind to a range of consoles specified by @first and @last. It will
- * also initialize the console driver by calling con_startup().
- */
-int register_con_driver(const struct consw *csw, int first, int last)
-{
- int retval;
-
- console_lock();
- retval = do_register_con_driver(csw, first, last);
- console_unlock();
- return retval;
-}
-EXPORT_SYMBOL(register_con_driver);
/**
- * unregister_con_driver - unregister console driver from console layer
+ * do_unregister_con_driver - unregister console driver from console layer
* @csw: console driver
*
* DESCRIPTION: All drivers that registers to the console layer must
@@ -3606,17 +3553,6 @@ EXPORT_SYMBOL(register_con_driver);
*
* The driver must unbind first prior to unregistration.
*/
-int unregister_con_driver(const struct consw *csw)
-{
- int retval;
-
- console_lock();
- retval = do_unregister_con_driver(csw);
- console_unlock();
- return retval;
-}
-EXPORT_SYMBOL(unregister_con_driver);
-
int do_unregister_con_driver(const struct consw *csw)
{
int i, retval = -ENODEV;
@@ -3654,7 +3590,7 @@ EXPORT_SYMBOL_GPL(do_unregister_con_driver);
* when a driver wants to take over some existing consoles
* and become default driver for newly opened ones.
*
- * take_over_console is basically a register followed by unbind
+ * do_take_over_console is basically a register followed by unbind
*/
int do_take_over_console(const struct consw *csw, int first, int last, int deflt)
{
@@ -3675,30 +3611,6 @@ int do_take_over_console(const struct consw *csw, int first, int last, int deflt
}
EXPORT_SYMBOL_GPL(do_take_over_console);
-/*
- * If we support more console drivers, this function is used
- * when a driver wants to take over some existing consoles
- * and become default driver for newly opened ones.
- *
- * take_over_console is basically a register followed by unbind
- */
-int take_over_console(const struct consw *csw, int first, int last, int deflt)
-{
- int err;
-
- err = register_con_driver(csw, first, last);
- /*
- * If we get an busy error we still want to bind the console driver
- * and return success, as we may have unbound the console driver
- * but not unregistered it.
- */
- if (err == -EBUSY)
- err = 0;
- if (!err)
- bind_con_driver(csw, first, last, deflt);
-
- return err;
-}
/*
* give_up_console is a wrapper to unregister_con_driver. It will only
@@ -3706,7 +3618,9 @@ int take_over_console(const struct consw *csw, int first, int last, int deflt)
*/
void give_up_console(const struct consw *csw)
{
- unregister_con_driver(csw);
+ console_lock();
+ do_unregister_con_driver(csw);
+ console_unlock();
}
static int __init vtconsole_class_init(void)
@@ -4262,6 +4176,5 @@ EXPORT_SYMBOL(console_blanked);
EXPORT_SYMBOL(vc_cons);
EXPORT_SYMBOL(global_cursor_default);
#ifndef VT_SINGLE_DRIVER
-EXPORT_SYMBOL(take_over_console);
EXPORT_SYMBOL(give_up_console);
#endif
generated by cgit v1.2.3 (git 2.0.4) at 2024-10-05 01:24:16 +0000