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path: root/drivers/char/tty_io.c
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Diffstat (limited to 'drivers/char/tty_io.c')
-rw-r--r--drivers/char/tty_io.c378
1 files changed, 210 insertions, 168 deletions
diff --git a/drivers/char/tty_io.c b/drivers/char/tty_io.c
index 98b65a230994..49c1a2267a55 100644
--- a/drivers/char/tty_io.c
+++ b/drivers/char/tty_io.c
@@ -78,6 +78,7 @@
#include <linux/tty_flip.h>
#include <linux/devpts_fs.h>
#include <linux/file.h>
+#include <linux/fdtable.h>
#include <linux/console.h>
#include <linux/timer.h>
#include <linux/ctype.h>
@@ -91,7 +92,6 @@
#include <linux/module.h>
#include <linux/smp_lock.h>
#include <linux/device.h>
-#include <linux/idr.h>
#include <linux/wait.h>
#include <linux/bitops.h>
#include <linux/delay.h>
@@ -137,9 +137,6 @@ EXPORT_SYMBOL(tty_mutex);
#ifdef CONFIG_UNIX98_PTYS
extern struct tty_driver *ptm_driver; /* Unix98 pty masters; for /dev/ptmx */
-extern int pty_limit; /* Config limit on Unix98 ptys */
-static DEFINE_IDR(allocated_ptys);
-static DEFINE_MUTEX(allocated_ptys_lock);
static int ptmx_open(struct inode *, struct file *);
#endif
@@ -152,8 +149,7 @@ ssize_t redirected_tty_write(struct file *, const char __user *,
static unsigned int tty_poll(struct file *, poll_table *);
static int tty_open(struct inode *, struct file *);
static int tty_release(struct inode *, struct file *);
-int tty_ioctl(struct inode *inode, struct file *file,
- unsigned int cmd, unsigned long arg);
+long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
#ifdef CONFIG_COMPAT
static long tty_compat_ioctl(struct file *file, unsigned int cmd,
unsigned long arg);
@@ -1109,8 +1105,8 @@ restart:
a reference to the old ldisc. If we ended up flipping back
to the existing ldisc we have two references to it */
- if (tty->ldisc.num != o_ldisc.num && tty->driver->set_ldisc)
- tty->driver->set_ldisc(tty);
+ if (tty->ldisc.num != o_ldisc.num && tty->ops->set_ldisc)
+ tty->ops->set_ldisc(tty);
tty_ldisc_put(o_ldisc.num);
@@ -1182,9 +1178,8 @@ struct tty_driver *tty_find_polling_driver(char *name, int *line)
if (*str == '\0')
str = NULL;
- if (tty_line >= 0 && tty_line <= p->num && p->poll_init &&
- !p->poll_init(p, tty_line, str)) {
-
+ if (tty_line >= 0 && tty_line <= p->num && p->ops &&
+ p->ops->poll_init && !p->ops->poll_init(p, tty_line, str)) {
res = p;
*line = tty_line;
break;
@@ -1205,26 +1200,37 @@ EXPORT_SYMBOL_GPL(tty_find_polling_driver);
* not in the foreground, send a SIGTTOU. If the signal is blocked or
* ignored, go ahead and perform the operation. (POSIX 7.2)
*
- * Locking: none
+ * Locking: ctrl_lock
*/
int tty_check_change(struct tty_struct *tty)
{
+ unsigned long flags;
+ int ret = 0;
+
if (current->signal->tty != tty)
return 0;
+
+ spin_lock_irqsave(&tty->ctrl_lock, flags);
+
if (!tty->pgrp) {
printk(KERN_WARNING "tty_check_change: tty->pgrp == NULL!\n");
- return 0;
+ goto out;
}
if (task_pgrp(current) == tty->pgrp)
- return 0;
+ goto out;
if (is_ignored(SIGTTOU))
- return 0;
- if (is_current_pgrp_orphaned())
- return -EIO;
+ goto out;
+ if (is_current_pgrp_orphaned()) {
+ ret = -EIO;
+ goto out;
+ }
kill_pgrp(task_pgrp(current), SIGTTOU, 1);
set_thread_flag(TIF_SIGPENDING);
- return -ERESTARTSYS;
+ ret = -ERESTARTSYS;
+out:
+ spin_unlock_irqrestore(&tty->ctrl_lock, flags);
+ return ret;
}
EXPORT_SYMBOL(tty_check_change);
@@ -1247,8 +1253,8 @@ static unsigned int hung_up_tty_poll(struct file *filp, poll_table *wait)
return POLLIN | POLLOUT | POLLERR | POLLHUP | POLLRDNORM | POLLWRNORM;
}
-static int hung_up_tty_ioctl(struct inode *inode, struct file *file,
- unsigned int cmd, unsigned long arg)
+static long hung_up_tty_ioctl(struct file *file, unsigned int cmd,
+ unsigned long arg)
{
return cmd == TIOCSPGRP ? -ENOTTY : -EIO;
}
@@ -1264,7 +1270,7 @@ static const struct file_operations tty_fops = {
.read = tty_read,
.write = tty_write,
.poll = tty_poll,
- .ioctl = tty_ioctl,
+ .unlocked_ioctl = tty_ioctl,
.compat_ioctl = tty_compat_ioctl,
.open = tty_open,
.release = tty_release,
@@ -1277,7 +1283,7 @@ static const struct file_operations ptmx_fops = {
.read = tty_read,
.write = tty_write,
.poll = tty_poll,
- .ioctl = tty_ioctl,
+ .unlocked_ioctl = tty_ioctl,
.compat_ioctl = tty_compat_ioctl,
.open = ptmx_open,
.release = tty_release,
@@ -1290,7 +1296,7 @@ static const struct file_operations console_fops = {
.read = tty_read,
.write = redirected_tty_write,
.poll = tty_poll,
- .ioctl = tty_ioctl,
+ .unlocked_ioctl = tty_ioctl,
.compat_ioctl = tty_compat_ioctl,
.open = tty_open,
.release = tty_release,
@@ -1302,7 +1308,7 @@ static const struct file_operations hung_up_tty_fops = {
.read = hung_up_tty_read,
.write = hung_up_tty_write,
.poll = hung_up_tty_poll,
- .ioctl = hung_up_tty_ioctl,
+ .unlocked_ioctl = hung_up_tty_ioctl,
.compat_ioctl = hung_up_tty_compat_ioctl,
.release = tty_release,
};
@@ -1404,6 +1410,7 @@ static void do_tty_hangup(struct work_struct *work)
struct task_struct *p;
struct tty_ldisc *ld;
int closecount = 0, n;
+ unsigned long flags;
if (!tty)
return;
@@ -1441,8 +1448,7 @@ static void do_tty_hangup(struct work_struct *work)
/* We may have no line discipline at this point */
if (ld->flush_buffer)
ld->flush_buffer(tty);
- if (tty->driver->flush_buffer)
- tty->driver->flush_buffer(tty);
+ tty_driver_flush_buffer(tty);
if ((test_bit(TTY_DO_WRITE_WAKEUP, &tty->flags)) &&
ld->write_wakeup)
ld->write_wakeup(tty);
@@ -1480,19 +1486,24 @@ static void do_tty_hangup(struct work_struct *work)
__group_send_sig_info(SIGHUP, SEND_SIG_PRIV, p);
__group_send_sig_info(SIGCONT, SEND_SIG_PRIV, p);
put_pid(p->signal->tty_old_pgrp); /* A noop */
+ spin_lock_irqsave(&tty->ctrl_lock, flags);
if (tty->pgrp)
p->signal->tty_old_pgrp = get_pid(tty->pgrp);
+ spin_unlock_irqrestore(&tty->ctrl_lock, flags);
spin_unlock_irq(&p->sighand->siglock);
} while_each_pid_task(tty->session, PIDTYPE_SID, p);
}
read_unlock(&tasklist_lock);
+ spin_lock_irqsave(&tty->ctrl_lock, flags);
tty->flags = 0;
put_pid(tty->session);
put_pid(tty->pgrp);
tty->session = NULL;
tty->pgrp = NULL;
tty->ctrl_status = 0;
+ spin_unlock_irqrestore(&tty->ctrl_lock, flags);
+
/*
* If one of the devices matches a console pointer, we
* cannot just call hangup() because that will cause
@@ -1500,11 +1511,11 @@ static void do_tty_hangup(struct work_struct *work)
* So we just call close() the right number of times.
*/
if (cons_filp) {
- if (tty->driver->close)
+ if (tty->ops->close)
for (n = 0; n < closecount; n++)
- tty->driver->close(tty, cons_filp);
- } else if (tty->driver->hangup)
- (tty->driver->hangup)(tty);
+ tty->ops->close(tty, cons_filp);
+ } else if (tty->ops->hangup)
+ (tty->ops->hangup)(tty);
/*
* We don't want to have driver/ldisc interactions beyond
* the ones we did here. The driver layer expects no
@@ -1626,16 +1637,17 @@ void disassociate_ctty(int on_exit)
struct tty_struct *tty;
struct pid *tty_pgrp = NULL;
- lock_kernel();
mutex_lock(&tty_mutex);
tty = get_current_tty();
if (tty) {
tty_pgrp = get_pid(tty->pgrp);
mutex_unlock(&tty_mutex);
+ lock_kernel();
/* XXX: here we race, there is nothing protecting tty */
if (on_exit && tty->driver->type != TTY_DRIVER_TYPE_PTY)
tty_vhangup(tty);
+ unlock_kernel();
} else if (on_exit) {
struct pid *old_pgrp;
spin_lock_irq(&current->sighand->siglock);
@@ -1648,7 +1660,6 @@ void disassociate_ctty(int on_exit)
put_pid(old_pgrp);
}
mutex_unlock(&tty_mutex);
- unlock_kernel();
return;
}
if (tty_pgrp) {
@@ -1667,10 +1678,13 @@ void disassociate_ctty(int on_exit)
/* It is possible that do_tty_hangup has free'd this tty */
tty = get_current_tty();
if (tty) {
+ unsigned long flags;
+ spin_lock_irqsave(&tty->ctrl_lock, flags);
put_pid(tty->session);
put_pid(tty->pgrp);
tty->session = NULL;
tty->pgrp = NULL;
+ spin_unlock_irqrestore(&tty->ctrl_lock, flags);
} else {
#ifdef TTY_DEBUG_HANGUP
printk(KERN_DEBUG "error attempted to write to tty [0x%p]"
@@ -1683,7 +1697,6 @@ void disassociate_ctty(int on_exit)
read_lock(&tasklist_lock);
session_clear_tty(task_session(current));
read_unlock(&tasklist_lock);
- unlock_kernel();
}
/**
@@ -1693,8 +1706,10 @@ void disassociate_ctty(int on_exit)
void no_tty(void)
{
struct task_struct *tsk = current;
+ lock_kernel();
if (tsk->signal->leader)
disassociate_ctty(0);
+ unlock_kernel();
proc_clear_tty(tsk);
}
@@ -1714,21 +1729,26 @@ void no_tty(void)
* but not always.
*
* Locking:
- * Broken. Relies on BKL which is unsafe here.
+ * Uses the tty control lock internally
*/
void stop_tty(struct tty_struct *tty)
{
- if (tty->stopped)
+ unsigned long flags;
+ spin_lock_irqsave(&tty->ctrl_lock, flags);
+ if (tty->stopped) {
+ spin_unlock_irqrestore(&tty->ctrl_lock, flags);
return;
+ }
tty->stopped = 1;
if (tty->link && tty->link->packet) {
tty->ctrl_status &= ~TIOCPKT_START;
tty->ctrl_status |= TIOCPKT_STOP;
wake_up_interruptible(&tty->link->read_wait);
}
- if (tty->driver->stop)
- (tty->driver->stop)(tty);
+ spin_unlock_irqrestore(&tty->ctrl_lock, flags);
+ if (tty->ops->stop)
+ (tty->ops->stop)(tty);
}
EXPORT_SYMBOL(stop_tty);
@@ -1743,21 +1763,26 @@ EXPORT_SYMBOL(stop_tty);
* driver start method is invoked and the line discipline woken.
*
* Locking:
- * Broken. Relies on BKL which is unsafe here.
+ * ctrl_lock
*/
void start_tty(struct tty_struct *tty)
{
- if (!tty->stopped || tty->flow_stopped)
+ unsigned long flags;
+ spin_lock_irqsave(&tty->ctrl_lock, flags);
+ if (!tty->stopped || tty->flow_stopped) {
+ spin_unlock_irqrestore(&tty->ctrl_lock, flags);
return;
+ }
tty->stopped = 0;
if (tty->link && tty->link->packet) {
tty->ctrl_status &= ~TIOCPKT_STOP;
tty->ctrl_status |= TIOCPKT_START;
wake_up_interruptible(&tty->link->read_wait);
}
- if (tty->driver->start)
- (tty->driver->start)(tty);
+ spin_unlock_irqrestore(&tty->ctrl_lock, flags);
+ if (tty->ops->start)
+ (tty->ops->start)(tty);
/* If we have a running line discipline it may need kicking */
tty_wakeup(tty);
}
@@ -1775,10 +1800,8 @@ EXPORT_SYMBOL(start_tty);
* for hung up devices before calling the line discipline method.
*
* Locking:
- * Locks the line discipline internally while needed
- * For historical reasons the line discipline read method is
- * invoked under the BKL. This will go away in time so do not rely on it
- * in new code. Multiple read calls may be outstanding in parallel.
+ * Locks the line discipline internally while needed. Multiple
+ * read calls may be outstanding in parallel.
*/
static ssize_t tty_read(struct file *file, char __user *buf, size_t count,
@@ -1799,13 +1822,11 @@ static ssize_t tty_read(struct file *file, char __user *buf, size_t count,
/* We want to wait for the line discipline to sort out in this
situation */
ld = tty_ldisc_ref_wait(tty);
- lock_kernel();
if (ld->read)
i = (ld->read)(tty, file, buf, count);
else
i = -EIO;
tty_ldisc_deref(ld);
- unlock_kernel();
if (i > 0)
inode->i_atime = current_fs_time(inode->i_sb);
return i;
@@ -1893,9 +1914,7 @@ static inline ssize_t do_tty_write(
ret = -EFAULT;
if (copy_from_user(tty->write_buf, buf, size))
break;
- lock_kernel();
ret = write(tty, file, tty->write_buf, size);
- unlock_kernel();
if (ret <= 0)
break;
written += ret;
@@ -1948,10 +1967,13 @@ static ssize_t tty_write(struct file *file, const char __user *buf,
tty = (struct tty_struct *)file->private_data;
if (tty_paranoia_check(tty, inode, "tty_write"))
return -EIO;
- if (!tty || !tty->driver->write ||
+ if (!tty || !tty->ops->write ||
(test_bit(TTY_IO_ERROR, &tty->flags)))
return -EIO;
-
+ /* Short term debug to catch buggy drivers */
+ if (tty->ops->write_room == NULL)
+ printk(KERN_ERR "tty driver %s lacks a write_room method.\n",
+ tty->driver->name);
ld = tty_ldisc_ref_wait(tty);
if (!ld->write)
ret = -EIO;
@@ -2098,6 +2120,7 @@ static int init_dev(struct tty_driver *driver, int idx,
goto fail_no_mem;
initialize_tty_struct(tty);
tty->driver = driver;
+ tty->ops = driver->ops;
tty->index = idx;
tty_line_name(driver, idx, tty->name);
@@ -2128,6 +2151,7 @@ static int init_dev(struct tty_driver *driver, int idx,
goto free_mem_out;
initialize_tty_struct(o_tty);
o_tty->driver = driver->other;
+ o_tty->ops = driver->ops;
o_tty->index = idx;
tty_line_name(driver->other, idx, o_tty->name);
@@ -2432,8 +2456,8 @@ static void release_dev(struct file *filp)
}
}
#endif
- if (tty->driver->close)
- tty->driver->close(tty, filp);
+ if (tty->ops->close)
+ tty->ops->close(tty, filp);
/*
* Sanity check: if tty->count is going to zero, there shouldn't be
@@ -2612,15 +2636,9 @@ static void release_dev(struct file *filp)
*/
release_tty(tty, idx);
-#ifdef CONFIG_UNIX98_PTYS
/* Make this pty number available for reallocation */
- if (devpts) {
- mutex_lock(&allocated_ptys_lock);
- idr_remove(&allocated_ptys, idx);
- mutex_unlock(&allocated_ptys_lock);
- }
-#endif
-
+ if (devpts)
+ devpts_kill_index(idx);
}
/**
@@ -2716,8 +2734,8 @@ got_driver:
printk(KERN_DEBUG "opening %s...", tty->name);
#endif
if (!retval) {
- if (tty->driver->open)
- retval = tty->driver->open(tty, filp);
+ if (tty->ops->open)
+ retval = tty->ops->open(tty, filp);
else
retval = -ENODEV;
}
@@ -2755,7 +2773,6 @@ got_driver:
__proc_set_tty(current, tty);
spin_unlock_irq(&current->sighand->siglock);
mutex_unlock(&tty_mutex);
- tty_audit_opening();
return 0;
}
@@ -2777,29 +2794,13 @@ static int ptmx_open(struct inode *inode, struct file *filp)
struct tty_struct *tty;
int retval;
int index;
- int idr_ret;
nonseekable_open(inode, filp);
/* find a device that is not in use. */
- mutex_lock(&allocated_ptys_lock);
- if (!idr_pre_get(&allocated_ptys, GFP_KERNEL)) {
- mutex_unlock(&allocated_ptys_lock);
- return -ENOMEM;
- }
- idr_ret = idr_get_new(&allocated_ptys, NULL, &index);
- if (idr_ret < 0) {
- mutex_unlock(&allocated_ptys_lock);
- if (idr_ret == -EAGAIN)
- return -ENOMEM;
- return -EIO;
- }
- if (index >= pty_limit) {
- idr_remove(&allocated_ptys, index);
- mutex_unlock(&allocated_ptys_lock);
- return -EIO;
- }
- mutex_unlock(&allocated_ptys_lock);
+ index = devpts_new_index();
+ if (index < 0)
+ return index;
mutex_lock(&tty_mutex);
retval = init_dev(ptm_driver, index, &tty);
@@ -2812,23 +2813,19 @@ static int ptmx_open(struct inode *inode, struct file *filp)
filp->private_data = tty;
file_move(filp, &tty->tty_files);
- retval = -ENOMEM;
- if (devpts_pty_new(tty->link))
+ retval = devpts_pty_new(tty->link);
+ if (retval)
goto out1;
- check_tty_count(tty, "tty_open");
- retval = ptm_driver->open(tty, filp);
- if (!retval) {
- tty_audit_opening();
+ check_tty_count(tty, "ptmx_open");
+ retval = ptm_driver->ops->open(tty, filp);
+ if (!retval)
return 0;
- }
out1:
release_dev(filp);
return retval;
out:
- mutex_lock(&allocated_ptys_lock);
- idr_remove(&allocated_ptys, index);
- mutex_unlock(&allocated_ptys_lock);
+ devpts_kill_index(index);
return retval;
}
#endif
@@ -2885,6 +2882,7 @@ static unsigned int tty_poll(struct file *filp, poll_table *wait)
static int tty_fasync(int fd, struct file *filp, int on)
{
struct tty_struct *tty;
+ unsigned long flags;
int retval;
tty = (struct tty_struct *)filp->private_data;
@@ -2900,6 +2898,7 @@ static int tty_fasync(int fd, struct file *filp, int on)
struct pid *pid;
if (!waitqueue_active(&tty->read_wait))
tty->minimum_to_wake = 1;
+ spin_lock_irqsave(&tty->ctrl_lock, flags);
if (tty->pgrp) {
pid = tty->pgrp;
type = PIDTYPE_PGID;
@@ -2907,6 +2906,7 @@ static int tty_fasync(int fd, struct file *filp, int on)
pid = task_pid(current);
type = PIDTYPE_PID;
}
+ spin_unlock_irqrestore(&tty->ctrl_lock, flags);
retval = __f_setown(filp, pid, type, 0);
if (retval)
return retval;
@@ -2992,6 +2992,8 @@ static int tiocswinsz(struct tty_struct *tty, struct tty_struct *real_tty,
struct winsize __user *arg)
{
struct winsize tmp_ws;
+ struct pid *pgrp, *rpgrp;
+ unsigned long flags;
if (copy_from_user(&tmp_ws, arg, sizeof(*arg)))
return -EFAULT;
@@ -3009,10 +3011,21 @@ static int tiocswinsz(struct tty_struct *tty, struct tty_struct *real_tty,
}
}
#endif
- if (tty->pgrp)
- kill_pgrp(tty->pgrp, SIGWINCH, 1);
- if ((real_tty->pgrp != tty->pgrp) && real_tty->pgrp)
- kill_pgrp(real_tty->pgrp, SIGWINCH, 1);
+ /* Get the PID values and reference them so we can
+ avoid holding the tty ctrl lock while sending signals */
+ spin_lock_irqsave(&tty->ctrl_lock, flags);
+ pgrp = get_pid(tty->pgrp);
+ rpgrp = get_pid(real_tty->pgrp);
+ spin_unlock_irqrestore(&tty->ctrl_lock, flags);
+
+ if (pgrp)
+ kill_pgrp(pgrp, SIGWINCH, 1);
+ if (rpgrp != pgrp && rpgrp)
+ kill_pgrp(rpgrp, SIGWINCH, 1);
+
+ put_pid(pgrp);
+ put_pid(rpgrp);
+
tty->winsize = tmp_ws;
real_tty->winsize = tmp_ws;
done:
@@ -3073,10 +3086,13 @@ static int fionbio(struct file *file, int __user *p)
if (get_user(nonblock, p))
return -EFAULT;
+ /* file->f_flags is still BKL protected in the fs layer - vomit */
+ lock_kernel();
if (nonblock)
file->f_flags |= O_NONBLOCK;
else
file->f_flags &= ~O_NONBLOCK;
+ unlock_kernel();
return 0;
}
@@ -3134,6 +3150,27 @@ unlock:
}
/**
+ * tty_get_pgrp - return a ref counted pgrp pid
+ * @tty: tty to read
+ *
+ * Returns a refcounted instance of the pid struct for the process
+ * group controlling the tty.
+ */
+
+struct pid *tty_get_pgrp(struct tty_struct *tty)
+{
+ unsigned long flags;
+ struct pid *pgrp;
+
+ spin_lock_irqsave(&tty->ctrl_lock, flags);
+ pgrp = get_pid(tty->pgrp);
+ spin_unlock_irqrestore(&tty->ctrl_lock, flags);
+
+ return pgrp;
+}
+EXPORT_SYMBOL_GPL(tty_get_pgrp);
+
+/**
* tiocgpgrp - get process group
* @tty: tty passed by user
* @real_tty: tty side of the tty pased by the user if a pty else the tty
@@ -3147,13 +3184,18 @@ unlock:
static int tiocgpgrp(struct tty_struct *tty, struct tty_struct *real_tty, pid_t __user *p)
{
+ struct pid *pid;
+ int ret;
/*
* (tty == real_tty) is a cheap way of
* testing if the tty is NOT a master pty.
*/
if (tty == real_tty && current->signal->tty != real_tty)
return -ENOTTY;
- return put_user(pid_vnr(real_tty->pgrp), p);
+ pid = tty_get_pgrp(real_tty);
+ ret = put_user(pid_vnr(pid), p);
+ put_pid(pid);
+ return ret;
}
/**
@@ -3165,7 +3207,7 @@ static int tiocgpgrp(struct tty_struct *tty, struct tty_struct *real_tty, pid_t
* Set the process group of the tty to the session passed. Only
* permitted where the tty session is our session.
*
- * Locking: None
+ * Locking: RCU, ctrl lock
*/
static int tiocspgrp(struct tty_struct *tty, struct tty_struct *real_tty, pid_t __user *p)
@@ -3173,6 +3215,7 @@ static int tiocspgrp(struct tty_struct *tty, struct tty_struct *real_tty, pid_t
struct pid *pgrp;
pid_t pgrp_nr;
int retval = tty_check_change(real_tty);
+ unsigned long flags;
if (retval == -EIO)
return -ENOTTY;
@@ -3195,8 +3238,10 @@ static int tiocspgrp(struct tty_struct *tty, struct tty_struct *real_tty, pid_t
if (session_of_pgrp(pgrp) != task_session(current))
goto out_unlock;
retval = 0;
+ spin_lock_irqsave(&tty->ctrl_lock, flags);
put_pid(real_tty->pgrp);
real_tty->pgrp = get_pid(pgrp);
+ spin_unlock_irqrestore(&tty->ctrl_lock, flags);
out_unlock:
rcu_read_unlock();
return retval;
@@ -3240,10 +3285,16 @@ static int tiocgsid(struct tty_struct *tty, struct tty_struct *real_tty, pid_t _
static int tiocsetd(struct tty_struct *tty, int __user *p)
{
int ldisc;
+ int ret;
if (get_user(ldisc, p))
return -EFAULT;
- return tty_set_ldisc(tty, ldisc);
+
+ lock_kernel();
+ ret = tty_set_ldisc(tty, ldisc);
+ unlock_kernel();
+
+ return ret;
}
/**
@@ -3263,18 +3314,18 @@ static int send_break(struct tty_struct *tty, unsigned int duration)
{
if (tty_write_lock(tty, 0) < 0)
return -EINTR;
- tty->driver->break_ctl(tty, -1);
+ tty->ops->break_ctl(tty, -1);
if (!signal_pending(current))
msleep_interruptible(duration);
- tty->driver->break_ctl(tty, 0);
+ tty->ops->break_ctl(tty, 0);
tty_write_unlock(tty);
- if (signal_pending(current))
+ if (!signal_pending(current))
return -EINTR;
return 0;
}
/**
- * tiocmget - get modem status
+ * tty_tiocmget - get modem status
* @tty: tty device
* @file: user file pointer
* @p: pointer to result
@@ -3289,8 +3340,8 @@ static int tty_tiocmget(struct tty_struct *tty, struct file *file, int __user *p
{
int retval = -EINVAL;
- if (tty->driver->tiocmget) {
- retval = tty->driver->tiocmget(tty, file);
+ if (tty->ops->tiocmget) {
+ retval = tty->ops->tiocmget(tty, file);
if (retval >= 0)
retval = put_user(retval, p);
@@ -3299,7 +3350,7 @@ static int tty_tiocmget(struct tty_struct *tty, struct file *file, int __user *p
}
/**
- * tiocmset - set modem status
+ * tty_tiocmset - set modem status
* @tty: tty device
* @file: user file pointer
* @cmd: command - clear bits, set bits or set all
@@ -3316,7 +3367,7 @@ static int tty_tiocmset(struct tty_struct *tty, struct file *file, unsigned int
{
int retval = -EINVAL;
- if (tty->driver->tiocmset) {
+ if (tty->ops->tiocmset) {
unsigned int set, clear, val;
retval = get_user(val, p);
@@ -3340,7 +3391,7 @@ static int tty_tiocmset(struct tty_struct *tty, struct file *file, unsigned int
set &= TIOCM_DTR|TIOCM_RTS|TIOCM_OUT1|TIOCM_OUT2|TIOCM_LOOP;
clear &= TIOCM_DTR|TIOCM_RTS|TIOCM_OUT1|TIOCM_OUT2|TIOCM_LOOP;
- retval = tty->driver->tiocmset(tty, file, set, clear);
+ retval = tty->ops->tiocmset(tty, file, set, clear);
}
return retval;
}
@@ -3348,20 +3399,18 @@ static int tty_tiocmset(struct tty_struct *tty, struct file *file, unsigned int
/*
* Split this up, as gcc can choke on it otherwise..
*/
-int tty_ioctl(struct inode *inode, struct file *file,
- unsigned int cmd, unsigned long arg)
+long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
struct tty_struct *tty, *real_tty;
void __user *p = (void __user *)arg;
int retval;
struct tty_ldisc *ld;
+ struct inode *inode = file->f_dentry->d_inode;
tty = (struct tty_struct *)file->private_data;
if (tty_paranoia_check(tty, inode, "tty_ioctl"))
return -EINVAL;
- /* CHECKME: is this safe as one end closes ? */
-
real_tty = tty;
if (tty->driver->type == TTY_DRIVER_TYPE_PTY &&
tty->driver->subtype == PTY_TYPE_MASTER)
@@ -3370,21 +3419,28 @@ int tty_ioctl(struct inode *inode, struct file *file,
/*
* Break handling by driver
*/
- if (!tty->driver->break_ctl) {
+
+ retval = -EINVAL;
+
+ if (!tty->ops->break_ctl) {
switch (cmd) {
case TIOCSBRK:
case TIOCCBRK:
- if (tty->driver->ioctl)
- return tty->driver->ioctl(tty, file, cmd, arg);
- return -EINVAL;
+ if (tty->ops->ioctl)
+ retval = tty->ops->ioctl(tty, file, cmd, arg);
+ if (retval != -EINVAL && retval != -ENOIOCTLCMD)
+ printk(KERN_WARNING "tty: driver %s needs updating to use break_ctl\n", tty->driver->name);
+ return retval;
/* These two ioctl's always return success; even if */
/* the driver doesn't support them. */
case TCSBRK:
case TCSBRKP:
- if (!tty->driver->ioctl)
+ if (!tty->ops->ioctl)
return 0;
- retval = tty->driver->ioctl(tty, file, cmd, arg);
+ retval = tty->ops->ioctl(tty, file, cmd, arg);
+ if (retval != -EINVAL && retval != -ENOIOCTLCMD)
+ printk(KERN_WARNING "tty: driver %s needs updating to use break_ctl\n", tty->driver->name);
if (retval == -ENOIOCTLCMD)
retval = 0;
return retval;
@@ -3442,7 +3498,6 @@ int tty_ioctl(struct inode *inode, struct file *file,
case TIOCGSID:
return tiocgsid(tty, real_tty, p);
case TIOCGETD:
- /* FIXME: check this is ok */
return put_user(tty->ldisc.num, (int __user *)p);
case TIOCSETD:
return tiocsetd(tty, p);
@@ -3454,11 +3509,13 @@ int tty_ioctl(struct inode *inode, struct file *file,
* Break handling
*/
case TIOCSBRK: /* Turn break on, unconditionally */
- tty->driver->break_ctl(tty, -1);
+ if (tty->ops->break_ctl)
+ tty->ops->break_ctl(tty, -1);
return 0;
case TIOCCBRK: /* Turn break off, unconditionally */
- tty->driver->break_ctl(tty, 0);
+ if (tty->ops->break_ctl)
+ tty->ops->break_ctl(tty, 0);
return 0;
case TCSBRK: /* SVID version: non-zero arg --> no break */
/* non-zero arg means wait for all output data
@@ -3487,8 +3544,8 @@ int tty_ioctl(struct inode *inode, struct file *file,
}
break;
}
- if (tty->driver->ioctl) {
- retval = (tty->driver->ioctl)(tty, file, cmd, arg);
+ if (tty->ops->ioctl) {
+ retval = (tty->ops->ioctl)(tty, file, cmd, arg);
if (retval != -ENOIOCTLCMD)
return retval;
}
@@ -3515,8 +3572,8 @@ static long tty_compat_ioctl(struct file *file, unsigned int cmd,
if (tty_paranoia_check(tty, inode, "tty_ioctl"))
return -EINVAL;
- if (tty->driver->compat_ioctl) {
- retval = (tty->driver->compat_ioctl)(tty, file, cmd, arg);
+ if (tty->ops->compat_ioctl) {
+ retval = (tty->ops->compat_ioctl)(tty, file, cmd, arg);
if (retval != -ENOIOCTLCMD)
return retval;
}
@@ -3566,8 +3623,7 @@ void __do_SAK(struct tty_struct *tty)
tty_ldisc_flush(tty);
- if (tty->driver->flush_buffer)
- tty->driver->flush_buffer(tty);
+ tty_driver_flush_buffer(tty);
read_lock(&tasklist_lock);
/* Kill the entire session */
@@ -3773,19 +3829,32 @@ static void initialize_tty_struct(struct tty_struct *tty)
mutex_init(&tty->atomic_read_lock);
mutex_init(&tty->atomic_write_lock);
spin_lock_init(&tty->read_lock);
+ spin_lock_init(&tty->ctrl_lock);
INIT_LIST_HEAD(&tty->tty_files);
INIT_WORK(&tty->SAK_work, do_SAK_work);
}
-/*
- * The default put_char routine if the driver did not define one.
+/**
+ * tty_put_char - write one character to a tty
+ * @tty: tty
+ * @ch: character
+ *
+ * Write one byte to the tty using the provided put_char method
+ * if present. Returns the number of characters successfully output.
+ *
+ * Note: the specific put_char operation in the driver layer may go
+ * away soon. Don't call it directly, use this method
*/
-static void tty_default_put_char(struct tty_struct *tty, unsigned char ch)
+int tty_put_char(struct tty_struct *tty, unsigned char ch)
{
- tty->driver->write(tty, &ch, 1);
+ if (tty->ops->put_char)
+ return tty->ops->put_char(tty, ch);
+ return tty->ops->write(tty, &ch, 1);
}
+EXPORT_SYMBOL_GPL(tty_put_char);
+
static struct class *tty_class;
/**
@@ -3868,37 +3937,8 @@ void put_tty_driver(struct tty_driver *driver)
void tty_set_operations(struct tty_driver *driver,
const struct tty_operations *op)
{
- driver->open = op->open;
- driver->close = op->close;
- driver->write = op->write;
- driver->put_char = op->put_char;
- driver->flush_chars = op->flush_chars;
- driver->write_room = op->write_room;
- driver->chars_in_buffer = op->chars_in_buffer;
- driver->ioctl = op->ioctl;
- driver->compat_ioctl = op->compat_ioctl;
- driver->set_termios = op->set_termios;
- driver->throttle = op->throttle;
- driver->unthrottle = op->unthrottle;
- driver->stop = op->stop;
- driver->start = op->start;
- driver->hangup = op->hangup;
- driver->break_ctl = op->break_ctl;
- driver->flush_buffer = op->flush_buffer;
- driver->set_ldisc = op->set_ldisc;
- driver->wait_until_sent = op->wait_until_sent;
- driver->send_xchar = op->send_xchar;
- driver->read_proc = op->read_proc;
- driver->write_proc = op->write_proc;
- driver->tiocmget = op->tiocmget;
- driver->tiocmset = op->tiocmset;
-#ifdef CONFIG_CONSOLE_POLL
- driver->poll_init = op->poll_init;
- driver->poll_get_char = op->poll_get_char;
- driver->poll_put_char = op->poll_put_char;
-#endif
-}
-
+ driver->ops = op;
+};
EXPORT_SYMBOL(alloc_tty_driver);
EXPORT_SYMBOL(put_tty_driver);
@@ -3961,9 +4001,6 @@ int tty_register_driver(struct tty_driver *driver)
return error;
}
- if (!driver->put_char)
- driver->put_char = tty_default_put_char;
-
mutex_lock(&tty_mutex);
list_add(&driver->tty_drivers, &tty_drivers);
mutex_unlock(&tty_mutex);
@@ -4039,14 +4076,19 @@ void proc_clear_tty(struct task_struct *p)
}
EXPORT_SYMBOL(proc_clear_tty);
+/* Called under the sighand lock */
+
static void __proc_set_tty(struct task_struct *tsk, struct tty_struct *tty)
{
if (tty) {
- /* We should not have a session or pgrp to here but.... */
+ unsigned long flags;
+ /* We should not have a session or pgrp to put here but.... */
+ spin_lock_irqsave(&tty->ctrl_lock, flags);
put_pid(tty->session);
put_pid(tty->pgrp);
- tty->session = get_pid(task_session(tsk));
tty->pgrp = get_pid(task_pgrp(tsk));
+ spin_unlock_irqrestore(&tty->ctrl_lock, flags);
+ tty->session = get_pid(task_session(tsk));
}
put_pid(tsk->signal->tty_old_pgrp);
tsk->signal->tty = tty;
generated by cgit v1.2.3 (git 2.0.4) at 2024-07-06 20:21:50 +0000