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path: root/drivers/tty/tty_io.c
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Diffstat (limited to 'drivers/tty/tty_io.c')
-rw-r--r--drivers/tty/tty_io.c1235
1 files changed, 788 insertions, 447 deletions
diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c
index c05c5af5aa0..34110719fe0 100644
--- a/drivers/tty/tty_io.c
+++ b/drivers/tty/tty_io.c
@@ -1,6 +1,4 @@
/*
- * linux/drivers/char/tty_io.c
- *
* Copyright (C) 1991, 1992 Linus Torvalds
*/
@@ -90,16 +88,15 @@
#include <linux/proc_fs.h>
#include <linux/init.h>
#include <linux/module.h>
-#include <linux/smp_lock.h>
#include <linux/device.h>
#include <linux/wait.h>
#include <linux/bitops.h>
#include <linux/delay.h>
#include <linux/seq_file.h>
#include <linux/serial.h>
+#include <linux/ratelimit.h>
#include <linux/uaccess.h>
-#include <asm/system.h>
#include <linux/kbd_kern.h>
#include <linux/vt_kern.h>
@@ -184,10 +181,12 @@ struct tty_struct *alloc_tty_struct(void)
void free_tty_struct(struct tty_struct *tty)
{
+ if (!tty)
+ return;
if (tty->dev)
put_device(tty->dev);
kfree(tty->write_buf);
- tty_buffer_free_all(tty);
+ tty->magic = 0xDEADDEAD;
kfree(tty);
}
@@ -196,8 +195,7 @@ static inline struct tty_struct *file_tty(struct file *file)
return ((struct tty_file_private *)file->private_data)->tty;
}
-/* Associate a new file with the tty structure */
-int tty_add_file(struct tty_struct *tty, struct file *file)
+int tty_alloc_file(struct file *file)
{
struct tty_file_private *priv;
@@ -205,27 +203,47 @@ int tty_add_file(struct tty_struct *tty, struct file *file)
if (!priv)
return -ENOMEM;
+ file->private_data = priv;
+
+ return 0;
+}
+
+/* Associate a new file with the tty structure */
+void tty_add_file(struct tty_struct *tty, struct file *file)
+{
+ struct tty_file_private *priv = file->private_data;
+
priv->tty = tty;
priv->file = file;
- file->private_data = priv;
spin_lock(&tty_files_lock);
list_add(&priv->list, &tty->tty_files);
spin_unlock(&tty_files_lock);
+}
- return 0;
+/**
+ * tty_free_file - free file->private_data
+ *
+ * This shall be used only for fail path handling when tty_add_file was not
+ * called yet.
+ */
+void tty_free_file(struct file *file)
+{
+ struct tty_file_private *priv = file->private_data;
+
+ file->private_data = NULL;
+ kfree(priv);
}
/* Delete file from its tty */
-void tty_del_file(struct file *file)
+static void tty_del_file(struct file *file)
{
struct tty_file_private *priv = file->private_data;
spin_lock(&tty_files_lock);
list_del(&priv->list);
spin_unlock(&tty_files_lock);
- file->private_data = NULL;
- kfree(priv);
+ tty_free_file(file);
}
@@ -515,10 +533,64 @@ void tty_wakeup(struct tty_struct *tty)
EXPORT_SYMBOL_GPL(tty_wakeup);
/**
+ * tty_signal_session_leader - sends SIGHUP to session leader
+ * @tty controlling tty
+ * @exit_session if non-zero, signal all foreground group processes
+ *
+ * Send SIGHUP and SIGCONT to the session leader and its process group.
+ * Optionally, signal all processes in the foreground process group.
+ *
+ * Returns the number of processes in the session with this tty
+ * as their controlling terminal. This value is used to drop
+ * tty references for those processes.
+ */
+static int tty_signal_session_leader(struct tty_struct *tty, int exit_session)
+{
+ struct task_struct *p;
+ int refs = 0;
+ struct pid *tty_pgrp = NULL;
+
+ read_lock(&tasklist_lock);
+ if (tty->session) {
+ do_each_pid_task(tty->session, PIDTYPE_SID, p) {
+ spin_lock_irq(&p->sighand->siglock);
+ if (p->signal->tty == tty) {
+ p->signal->tty = NULL;
+ /* We defer the dereferences outside fo
+ the tasklist lock */
+ refs++;
+ }
+ if (!p->signal->leader) {
+ spin_unlock_irq(&p->sighand->siglock);
+ continue;
+ }
+ __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(&tty->ctrl_lock);
+ tty_pgrp = get_pid(tty->pgrp);
+ if (tty->pgrp)
+ p->signal->tty_old_pgrp = get_pid(tty->pgrp);
+ spin_unlock(&tty->ctrl_lock);
+ spin_unlock_irq(&p->sighand->siglock);
+ } while_each_pid_task(tty->session, PIDTYPE_SID, p);
+ }
+ read_unlock(&tasklist_lock);
+
+ if (tty_pgrp) {
+ if (exit_session)
+ kill_pgrp(tty_pgrp, SIGHUP, exit_session);
+ put_pid(tty_pgrp);
+ }
+
+ return refs;
+}
+
+/**
* __tty_hangup - actual handler for hangup events
* @work: tty device
*
- * This can be called by the "eventd" kernel thread. That is process
+ * This can be called by a "kworker" kernel thread. That is process
* synchronous but doesn't hold any locks, so we need to make sure we
* have the appropriate locks for what we're doing.
*
@@ -531,20 +603,18 @@ EXPORT_SYMBOL_GPL(tty_wakeup);
* BTM
* redirect lock for undoing redirection
* file list lock for manipulating list of ttys
- * tty_ldisc_lock from called functions
- * termios_mutex resetting termios data
+ * tty_ldiscs_lock from called functions
+ * termios_rwsem resetting termios data
* tasklist_lock to walk task list for hangup event
* ->siglock to protect ->signal/->sighand
*/
-void __tty_hangup(struct tty_struct *tty)
+static void __tty_hangup(struct tty_struct *tty, int exit_session)
{
struct file *cons_filp = NULL;
struct file *filp, *f = NULL;
- struct task_struct *p;
struct tty_file_private *priv;
int closecount = 0, n;
- unsigned long flags;
- int refs = 0;
+ int refs;
if (!tty)
return;
@@ -557,7 +627,15 @@ void __tty_hangup(struct tty_struct *tty)
}
spin_unlock(&redirect_lock);
- tty_lock();
+ tty_lock(tty);
+
+ if (test_bit(TTY_HUPPED, &tty->flags)) {
+ tty_unlock(tty);
+ return;
+ }
+
+ /* some functions below drop BTM, so we need this bit */
+ set_bit(TTY_HUPPING, &tty->flags);
/* inuse_filps is protected by the single tty lock,
this really needs to change if we want to flush the
@@ -578,49 +656,26 @@ void __tty_hangup(struct tty_struct *tty)
}
spin_unlock(&tty_files_lock);
- tty_ldisc_hangup(tty);
+ refs = tty_signal_session_leader(tty, exit_session);
+ /* Account for the p->signal references we killed */
+ while (refs--)
+ tty_kref_put(tty);
- read_lock(&tasklist_lock);
- if (tty->session) {
- do_each_pid_task(tty->session, PIDTYPE_SID, p) {
- spin_lock_irq(&p->sighand->siglock);
- if (p->signal->tty == tty) {
- p->signal->tty = NULL;
- /* We defer the dereferences outside fo
- the tasklist lock */
- refs++;
- }
- if (!p->signal->leader) {
- spin_unlock_irq(&p->sighand->siglock);
- continue;
- }
- __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);
+ /*
+ * it drops BTM and thus races with reopen
+ * we protect the race by TTY_HUPPING
+ */
+ tty_ldisc_hangup(tty);
- spin_lock_irqsave(&tty->ctrl_lock, flags);
+ spin_lock_irq(&tty->ctrl_lock);
clear_bit(TTY_THROTTLED, &tty->flags);
- clear_bit(TTY_PUSH, &tty->flags);
clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
put_pid(tty->session);
put_pid(tty->pgrp);
tty->session = NULL;
tty->pgrp = NULL;
tty->ctrl_status = 0;
- set_bit(TTY_HUPPED, &tty->flags);
- spin_unlock_irqrestore(&tty->ctrl_lock, flags);
-
- /* Account for the p->signal references we killed */
- while (refs--)
- tty_kref_put(tty);
+ spin_unlock_irq(&tty->ctrl_lock);
/*
* If one of the devices matches a console pointer, we
@@ -641,9 +696,9 @@ void __tty_hangup(struct tty_struct *tty)
* can't yet guarantee all that.
*/
set_bit(TTY_HUPPED, &tty->flags);
- tty_ldisc_enable(tty);
+ clear_bit(TTY_HUPPING, &tty->flags);
- tty_unlock();
+ tty_unlock(tty);
if (f)
fput(f);
@@ -654,7 +709,7 @@ static void do_tty_hangup(struct work_struct *work)
struct tty_struct *tty =
container_of(work, struct tty_struct, hangup_work);
- __tty_hangup(tty);
+ __tty_hangup(tty, 0);
}
/**
@@ -692,7 +747,7 @@ void tty_vhangup(struct tty_struct *tty)
printk(KERN_DEBUG "%s vhangup...\n", tty_name(tty, buf));
#endif
- __tty_hangup(tty);
+ __tty_hangup(tty, 0);
}
EXPORT_SYMBOL(tty_vhangup);
@@ -716,6 +771,27 @@ void tty_vhangup_self(void)
}
/**
+ * tty_vhangup_session - hangup session leader exit
+ * @tty: tty to hangup
+ *
+ * The session leader is exiting and hanging up its controlling terminal.
+ * Every process in the foreground process group is signalled SIGHUP.
+ *
+ * We do this synchronously so that when the syscall returns the process
+ * is complete. That guarantee is necessary for security reasons.
+ */
+
+static void tty_vhangup_session(struct tty_struct *tty)
+{
+#ifdef TTY_DEBUG_HANGUP
+ char buf[64];
+
+ printk(KERN_DEBUG "%s vhangup session...\n", tty_name(tty, buf));
+#endif
+ __tty_hangup(tty, 1);
+}
+
+/**
* tty_hung_up_p - was tty hung up
* @filp: file pointer of tty
*
@@ -766,19 +842,25 @@ static void session_clear_tty(struct pid *session)
void disassociate_ctty(int on_exit)
{
struct tty_struct *tty;
- struct pid *tty_pgrp = NULL;
if (!current->signal->leader)
return;
tty = get_current_tty();
if (tty) {
- tty_pgrp = get_pid(tty->pgrp);
- if (on_exit) {
- if (tty->driver->type != TTY_DRIVER_TYPE_PTY)
- tty_vhangup(tty);
+ if (on_exit && tty->driver->type != TTY_DRIVER_TYPE_PTY) {
+ tty_vhangup_session(tty);
+ } else {
+ struct pid *tty_pgrp = tty_get_pgrp(tty);
+ if (tty_pgrp) {
+ kill_pgrp(tty_pgrp, SIGHUP, on_exit);
+ if (!on_exit)
+ kill_pgrp(tty_pgrp, SIGCONT, on_exit);
+ put_pid(tty_pgrp);
+ }
}
tty_kref_put(tty);
+
} else if (on_exit) {
struct pid *old_pgrp;
spin_lock_irq(&current->sighand->siglock);
@@ -792,19 +874,12 @@ void disassociate_ctty(int on_exit)
}
return;
}
- if (tty_pgrp) {
- kill_pgrp(tty_pgrp, SIGHUP, on_exit);
- if (!on_exit)
- kill_pgrp(tty_pgrp, SIGCONT, on_exit);
- put_pid(tty_pgrp);
- }
spin_lock_irq(&current->sighand->siglock);
put_pid(current->signal->tty_old_pgrp);
current->signal->tty_old_pgrp = NULL;
- spin_unlock_irq(&current->sighand->siglock);
- tty = get_current_tty();
+ tty = tty_kref_get(current->signal->tty);
if (tty) {
unsigned long flags;
spin_lock_irqsave(&tty->ctrl_lock, flags);
@@ -821,6 +896,7 @@ void disassociate_ctty(int on_exit)
#endif
}
+ spin_unlock_irq(&current->sighand->siglock);
/* Now clear signal->tty under the lock */
read_lock(&tasklist_lock);
session_clear_tty(task_session(current));
@@ -833,10 +909,11 @@ void disassociate_ctty(int on_exit)
*/
void no_tty(void)
{
+ /* FIXME: Review locking here. The tty_lock never covered any race
+ between a new association and proc_clear_tty but possible we need
+ to protect against this anyway */
struct task_struct *tsk = current;
- tty_lock();
disassociate_ctty(0);
- tty_unlock();
proc_clear_tty(tsk);
}
@@ -916,6 +993,14 @@ void start_tty(struct tty_struct *tty)
EXPORT_SYMBOL(start_tty);
+/* We limit tty time update visibility to every 8 seconds or so. */
+static void tty_update_time(struct timespec *time)
+{
+ unsigned long sec = get_seconds() & ~7;
+ if ((long)(sec - time->tv_sec) > 0)
+ time->tv_sec = sec;
+}
+
/**
* tty_read - read method for tty device files
* @file: pointer to tty file
@@ -935,7 +1020,7 @@ static ssize_t tty_read(struct file *file, char __user *buf, size_t count,
loff_t *ppos)
{
int i;
- struct inode *inode = file->f_path.dentry->d_inode;
+ struct inode *inode = file_inode(file);
struct tty_struct *tty = file_tty(file);
struct tty_ldisc *ld;
@@ -952,18 +1037,22 @@ static ssize_t tty_read(struct file *file, char __user *buf, size_t count,
else
i = -EIO;
tty_ldisc_deref(ld);
+
if (i > 0)
- inode->i_atime = current_fs_time(inode->i_sb);
+ tty_update_time(&inode->i_atime);
+
return i;
}
void tty_write_unlock(struct tty_struct *tty)
+ __releases(&tty->atomic_write_lock)
{
mutex_unlock(&tty->atomic_write_lock);
wake_up_interruptible_poll(&tty->write_wait, POLLOUT);
}
int tty_write_lock(struct tty_struct *tty, int ndelay)
+ __acquires(&tty->atomic_write_lock)
{
if (!mutex_trylock(&tty->atomic_write_lock)) {
if (ndelay)
@@ -1053,8 +1142,7 @@ static inline ssize_t do_tty_write(
cond_resched();
}
if (written) {
- struct inode *inode = file->f_path.dentry->d_inode;
- inode->i_mtime = current_fs_time(inode->i_sb);
+ tty_update_time(&file_inode(file)->i_mtime);
ret = written;
}
out:
@@ -1078,12 +1166,12 @@ void tty_write_message(struct tty_struct *tty, char *msg)
{
if (tty) {
mutex_lock(&tty->atomic_write_lock);
- tty_lock();
+ tty_lock(tty);
if (tty->ops->write && !test_bit(TTY_CLOSING, &tty->flags)) {
- tty_unlock();
+ tty_unlock(tty);
tty->ops->write(tty, msg, strlen(msg));
} else
- tty_unlock();
+ tty_unlock(tty);
tty_write_unlock(tty);
}
return;
@@ -1109,12 +1197,11 @@ void tty_write_message(struct tty_struct *tty, char *msg)
static ssize_t tty_write(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
- struct inode *inode = file->f_path.dentry->d_inode;
struct tty_struct *tty = file_tty(file);
struct tty_ldisc *ld;
ssize_t ret;
- if (tty_paranoia_check(tty, inode, "tty_write"))
+ if (tty_paranoia_check(tty, file_inode(file), "tty_write"))
return -EIO;
if (!tty || !tty->ops->write ||
(test_bit(TTY_IO_ERROR, &tty->flags)))
@@ -1138,10 +1225,8 @@ ssize_t redirected_tty_write(struct file *file, const char __user *buf,
struct file *p = NULL;
spin_lock(&redirect_lock);
- if (redirect) {
- get_file(redirect);
- p = redirect;
- }
+ if (redirect)
+ p = get_file(redirect);
spin_unlock(&redirect_lock);
if (p) {
@@ -1186,9 +1271,13 @@ static void pty_line_name(struct tty_driver *driver, int index, char *p)
*
* Locking: None
*/
-static void tty_line_name(struct tty_driver *driver, int index, char *p)
+static ssize_t tty_line_name(struct tty_driver *driver, int index, char *p)
{
- sprintf(p, "%s%d", driver->name, index + driver->name_base);
+ if (driver->flags & TTY_DRIVER_UNNUMBERED_NODE)
+ return sprintf(p, "%s", driver->name);
+ else
+ return sprintf(p, "%s%d", driver->name,
+ index + driver->name_base);
}
/**
@@ -1205,13 +1294,10 @@ static void tty_line_name(struct tty_driver *driver, int index, char *p)
static struct tty_struct *tty_driver_lookup_tty(struct tty_driver *driver,
struct inode *inode, int idx)
{
- struct tty_struct *tty;
-
if (driver->ops->lookup)
return driver->ops->lookup(driver, inode, idx);
- tty = driver->ttys[idx];
- return tty;
+ return driver->ttys[idx];
}
/**
@@ -1227,25 +1313,36 @@ int tty_init_termios(struct tty_struct *tty)
struct ktermios *tp;
int idx = tty->index;
- tp = tty->driver->termios[idx];
- if (tp == NULL) {
- tp = kzalloc(sizeof(struct ktermios[2]), GFP_KERNEL);
- if (tp == NULL)
- return -ENOMEM;
- memcpy(tp, &tty->driver->init_termios,
- sizeof(struct ktermios));
- tty->driver->termios[idx] = tp;
+ if (tty->driver->flags & TTY_DRIVER_RESET_TERMIOS)
+ tty->termios = tty->driver->init_termios;
+ else {
+ /* Check for lazy saved data */
+ tp = tty->driver->termios[idx];
+ if (tp != NULL)
+ tty->termios = *tp;
+ else
+ tty->termios = tty->driver->init_termios;
}
- tty->termios = tp;
- tty->termios_locked = tp + 1;
-
/* Compatibility until drivers always set this */
- tty->termios->c_ispeed = tty_termios_input_baud_rate(tty->termios);
- tty->termios->c_ospeed = tty_termios_baud_rate(tty->termios);
+ tty->termios.c_ispeed = tty_termios_input_baud_rate(&tty->termios);
+ tty->termios.c_ospeed = tty_termios_baud_rate(&tty->termios);
return 0;
}
EXPORT_SYMBOL_GPL(tty_init_termios);
+int tty_standard_install(struct tty_driver *driver, struct tty_struct *tty)
+{
+ int ret = tty_init_termios(tty);
+ if (ret)
+ return ret;
+
+ tty_driver_kref_get(driver);
+ tty->count++;
+ driver->ttys[tty->index] = tty;
+ return 0;
+}
+EXPORT_SYMBOL_GPL(tty_standard_install);
+
/**
* tty_driver_install_tty() - install a tty entry in the driver
* @driver: the driver for the tty
@@ -1261,21 +1358,8 @@ EXPORT_SYMBOL_GPL(tty_init_termios);
static int tty_driver_install_tty(struct tty_driver *driver,
struct tty_struct *tty)
{
- int idx = tty->index;
- int ret;
-
- if (driver->ops->install) {
- ret = driver->ops->install(driver, tty);
- return ret;
- }
-
- if (tty_init_termios(tty) == 0) {
- tty_driver_kref_get(driver);
- tty->count++;
- driver->ttys[idx] = tty;
- return 0;
- }
- return -ENOMEM;
+ return driver->ops->install ? driver->ops->install(driver, tty) :
+ tty_standard_install(driver, tty);
}
/**
@@ -1288,8 +1372,7 @@ static int tty_driver_install_tty(struct tty_driver *driver,
*
* Locking: tty_mutex for now
*/
-static void tty_driver_remove_tty(struct tty_driver *driver,
- struct tty_struct *tty)
+void tty_driver_remove_tty(struct tty_driver *driver, struct tty_struct *tty)
{
if (driver->ops->remove)
driver->ops->remove(driver, tty);
@@ -1310,7 +1393,8 @@ static int tty_reopen(struct tty_struct *tty)
{
struct tty_driver *driver = tty->driver;
- if (test_bit(TTY_CLOSING, &tty->flags))
+ if (test_bit(TTY_CLOSING, &tty->flags) ||
+ test_bit(TTY_HUPPING, &tty->flags))
return -EIO;
if (driver->type == TTY_DRIVER_TYPE_PTY &&
@@ -1325,11 +1409,8 @@ static int tty_reopen(struct tty_struct *tty)
tty->link->count++;
}
tty->count++;
- tty->driver = driver; /* N.B. why do this every time?? */
- mutex_lock(&tty->ldisc_mutex);
- WARN_ON(!test_bit(TTY_LDISC, &tty->flags));
- mutex_unlock(&tty->ldisc_mutex);
+ WARN_ON(!tty->ldisc);
return 0;
}
@@ -1339,7 +1420,6 @@ static int tty_reopen(struct tty_struct *tty)
* @driver: tty driver we are opening a device on
* @idx: device index
* @ret_tty: returned tty structure
- * @first_ok: ok to open a new device (used by ptmx)
*
* Prepare a tty device. This may not be a "new" clean device but
* could also be an active device. The pty drivers require special
@@ -1359,18 +1439,11 @@ static int tty_reopen(struct tty_struct *tty)
* relaxed for the (most common) case of reopening a tty.
*/
-struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx,
- int first_ok)
+struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx)
{
struct tty_struct *tty;
int retval;
- /* Check if pty master is being opened multiple times */
- if (driver->subtype == PTY_TYPE_MASTER &&
- (driver->flags & TTY_DRIVER_DEVPTS_MEM) && !first_ok) {
- return ERR_PTR(-EIO);
- }
-
/*
* First time open is complex, especially for PTY devices.
* This code guarantees that either everything succeeds and the
@@ -1383,16 +1456,25 @@ struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx,
return ERR_PTR(-ENODEV);
tty = alloc_tty_struct();
- if (!tty)
- goto fail_no_mem;
+ if (!tty) {
+ retval = -ENOMEM;
+ goto err_module_put;
+ }
initialize_tty_struct(tty, driver, idx);
+ tty_lock(tty);
retval = tty_driver_install_tty(driver, tty);
- if (retval < 0) {
- free_tty_struct(tty);
- module_put(driver->owner);
- return ERR_PTR(retval);
- }
+ if (retval < 0)
+ goto err_deinit_tty;
+
+ if (!tty->port)
+ tty->port = driver->ports[idx];
+
+ WARN_RATELIMIT(!tty->port,
+ "%s: %s driver does not set tty->port. This will crash the kernel later. Fix the driver!\n",
+ __func__, tty->driver->name);
+
+ tty->port->itty = tty;
/*
* Structures all installed ... call the ldisc open routines.
@@ -1401,17 +1483,22 @@ struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx,
*/
retval = tty_ldisc_setup(tty, tty->link);
if (retval)
- goto release_mem_out;
+ goto err_release_tty;
+ /* Return the tty locked so that it cannot vanish under the caller */
return tty;
-fail_no_mem:
+err_deinit_tty:
+ tty_unlock(tty);
+ deinitialize_tty_struct(tty);
+ free_tty_struct(tty);
+err_module_put:
module_put(driver->owner);
- return ERR_PTR(-ENOMEM);
+ return ERR_PTR(retval);
/* call the tty release_tty routine to clean out this slot */
-release_mem_out:
- if (printk_ratelimit())
- printk(KERN_INFO "tty_init_dev: ldisc open failed, "
+err_release_tty:
+ tty_unlock(tty);
+ printk_ratelimited(KERN_INFO "tty_init_dev: ldisc open failed, "
"clearing slot %d\n", idx);
release_tty(tty, idx);
return ERR_PTR(retval);
@@ -1421,22 +1508,36 @@ void tty_free_termios(struct tty_struct *tty)
{
struct ktermios *tp;
int idx = tty->index;
- /* Kill this flag and push into drivers for locking etc */
- if (tty->driver->flags & TTY_DRIVER_RESET_TERMIOS) {
- /* FIXME: Locking on ->termios array */
- tp = tty->termios;
- tty->driver->termios[idx] = NULL;
- kfree(tp);
+
+ /* If the port is going to reset then it has no termios to save */
+ if (tty->driver->flags & TTY_DRIVER_RESET_TERMIOS)
+ return;
+
+ /* Stash the termios data */
+ tp = tty->driver->termios[idx];
+ if (tp == NULL) {
+ tp = kmalloc(sizeof(struct ktermios), GFP_KERNEL);
+ if (tp == NULL) {
+ pr_warn("tty: no memory to save termios state.\n");
+ return;
+ }
+ tty->driver->termios[idx] = tp;
}
+ *tp = tty->termios;
}
EXPORT_SYMBOL(tty_free_termios);
-void tty_shutdown(struct tty_struct *tty)
+/**
+ * tty_flush_works - flush all works of a tty
+ * @tty: tty device to flush works for
+ *
+ * Sync flush all works belonging to @tty.
+ */
+static void tty_flush_works(struct tty_struct *tty)
{
- tty_driver_remove_tty(tty->driver, tty);
- tty_free_termios(tty);
+ flush_work(&tty->SAK_work);
+ flush_work(&tty->hangup_work);
}
-EXPORT_SYMBOL(tty_shutdown);
/**
* release_one_tty - release tty structure memory
@@ -1447,7 +1548,6 @@ EXPORT_SYMBOL(tty_shutdown);
* in use. It also gets called when setup of a device fails.
*
* Locking:
- * tty_mutex - sometimes only
* takes the file list lock internally when working on the list
* of ttys that the driver keeps.
*
@@ -1480,11 +1580,6 @@ static void queue_release_one_tty(struct kref *kref)
{
struct tty_struct *tty = container_of(kref, struct tty_struct, kref);
- if (tty->ops->shutdown)
- tty->ops->shutdown(tty);
- else
- tty_shutdown(tty);
-
/* The hangup queue is now free so we can reuse it rather than
waste a chunk of memory for each port */
INIT_WORK(&tty->hangup_work, release_one_tty);
@@ -1513,16 +1608,24 @@ EXPORT_SYMBOL(tty_kref_put);
* and decrement the refcount of the backing module.
*
* Locking:
- * tty_mutex - sometimes only
+ * tty_mutex
* takes the file list lock internally when working on the list
* of ttys that the driver keeps.
- * FIXME: should we require tty_mutex is held here ??
*
*/
static void release_tty(struct tty_struct *tty, int idx)
{
/* This should always be true but check for the moment */
WARN_ON(tty->index != idx);
+ WARN_ON(!mutex_is_locked(&tty_mutex));
+ if (tty->ops->shutdown)
+ tty->ops->shutdown(tty);
+ tty_free_termios(tty);
+ tty_driver_remove_tty(tty->driver, tty);
+ tty->port->itty = NULL;
+ if (tty->link)
+ tty->link->port->itty = NULL;
+ cancel_work_sync(&tty->port->buf.work);
if (tty->link)
tty_kref_put(tty->link);
@@ -1530,6 +1633,49 @@ static void release_tty(struct tty_struct *tty, int idx)
}
/**
+ * tty_release_checks - check a tty before real release
+ * @tty: tty to check
+ * @o_tty: link of @tty (if any)
+ * @idx: index of the tty
+ *
+ * Performs some paranoid checking before true release of the @tty.
+ * This is a no-op unless TTY_PARANOIA_CHECK is defined.
+ */
+static int tty_release_checks(struct tty_struct *tty, struct tty_struct *o_tty,
+ int idx)
+{
+#ifdef TTY_PARANOIA_CHECK
+ if (idx < 0 || idx >= tty->driver->num) {
+ printk(KERN_DEBUG "%s: bad idx when trying to free (%s)\n",
+ __func__, tty->name);
+ return -1;
+ }
+
+ /* not much to check for devpts */
+ if (tty->driver->flags & TTY_DRIVER_DEVPTS_MEM)
+ return 0;
+
+ if (tty != tty->driver->ttys[idx]) {
+ printk(KERN_DEBUG "%s: driver.table[%d] not tty for (%s)\n",
+ __func__, idx, tty->name);
+ return -1;
+ }
+ if (tty->driver->other) {
+ if (o_tty != tty->driver->other->ttys[idx]) {
+ printk(KERN_DEBUG "%s: other->table[%d] not o_tty for (%s)\n",
+ __func__, idx, tty->name);
+ return -1;
+ }
+ if (o_tty->link != tty) {
+ printk(KERN_DEBUG "%s: bad pty pointers\n", __func__);
+ return -1;
+ }
+ }
+#endif
+ return 0;
+}
+
+/**
* tty_release - vfs callback for close
* @inode: inode of tty
* @filp: file pointer for handle to tty
@@ -1553,81 +1699,37 @@ int tty_release(struct inode *inode, struct file *filp)
struct tty_struct *tty = file_tty(filp);
struct tty_struct *o_tty;
int pty_master, tty_closing, o_tty_closing, do_sleep;
- int devpts;
int idx;
char buf[64];
- if (tty_paranoia_check(tty, inode, "tty_release_dev"))
+ if (tty_paranoia_check(tty, inode, __func__))
return 0;
- tty_lock();
- check_tty_count(tty, "tty_release_dev");
+ tty_lock(tty);
+ check_tty_count(tty, __func__);
__tty_fasync(-1, filp, 0);
idx = tty->index;
pty_master = (tty->driver->type == TTY_DRIVER_TYPE_PTY &&
tty->driver->subtype == PTY_TYPE_MASTER);
- devpts = (tty->driver->flags & TTY_DRIVER_DEVPTS_MEM) != 0;
+ /* Review: parallel close */
o_tty = tty->link;
-#ifdef TTY_PARANOIA_CHECK
- if (idx < 0 || idx >= tty->driver->num) {
- printk(KERN_DEBUG "tty_release_dev: bad idx when trying to "
- "free (%s)\n", tty->name);
- tty_unlock();
+ if (tty_release_checks(tty, o_tty, idx)) {
+ tty_unlock(tty);
return 0;
}
- if (!devpts) {
- if (tty != tty->driver->ttys[idx]) {
- tty_unlock();
- printk(KERN_DEBUG "tty_release_dev: driver.table[%d] not tty "
- "for (%s)\n", idx, tty->name);
- return 0;
- }
- if (tty->termios != tty->driver->termios[idx]) {
- tty_unlock();
- printk(KERN_DEBUG "tty_release_dev: driver.termios[%d] not termios "
- "for (%s)\n",
- idx, tty->name);
- return 0;
- }
- }
-#endif
#ifdef TTY_DEBUG_HANGUP
- printk(KERN_DEBUG "tty_release_dev of %s (tty count=%d)...",
- tty_name(tty, buf), tty->count);
+ printk(KERN_DEBUG "%s: %s (tty count=%d)...\n", __func__,
+ tty_name(tty, buf), tty->count);
#endif
-#ifdef TTY_PARANOIA_CHECK
- if (tty->driver->other &&
- !(tty->driver->flags & TTY_DRIVER_DEVPTS_MEM)) {
- if (o_tty != tty->driver->other->ttys[idx]) {
- tty_unlock();
- printk(KERN_DEBUG "tty_release_dev: other->table[%d] "
- "not o_tty for (%s)\n",
- idx, tty->name);
- return 0 ;
- }
- if (o_tty->termios != tty->driver->other->termios[idx]) {
- tty_unlock();
- printk(KERN_DEBUG "tty_release_dev: other->termios[%d] "
- "not o_termios for (%s)\n",
- idx, tty->name);
- return 0;
- }
- if (o_tty->link != tty) {
- tty_unlock();
- printk(KERN_DEBUG "tty_release_dev: bad pty pointers\n");
- return 0;
- }
- }
-#endif
if (tty->ops->close)
tty->ops->close(tty, filp);
- tty_unlock();
+ tty_unlock(tty);
/*
* Sanity check: if tty->count is going to zero, there shouldn't be
* any waiters on tty->read_wait or tty->write_wait. We test the
@@ -1650,7 +1752,7 @@ int tty_release(struct inode *inode, struct file *filp)
opens on /dev/tty */
mutex_lock(&tty_mutex);
- tty_lock();
+ tty_lock_pair(tty, o_tty);
tty_closing = tty->count <= 1;
o_tty_closing = o_tty &&
(o_tty->count <= (pty_master ? 1 : 0));
@@ -1679,9 +1781,9 @@ int tty_release(struct inode *inode, struct file *filp)
if (!do_sleep)
break;
- printk(KERN_WARNING "tty_release_dev: %s: read/write wait queue "
- "active!\n", tty_name(tty, buf));
- tty_unlock();
+ printk(KERN_WARNING "%s: %s: read/write wait queue active!\n",
+ __func__, tty_name(tty, buf));
+ tty_unlock_pair(tty, o_tty);
mutex_unlock(&tty_mutex);
schedule();
}
@@ -1690,18 +1792,20 @@ int tty_release(struct inode *inode, struct file *filp)
* The closing flags are now consistent with the open counts on
* both sides, and we've completed the last operation that could
* block, so it's safe to proceed with closing.
+ *
+ * We must *not* drop the tty_mutex until we ensure that a further
+ * entry into tty_open can not pick up this tty.
*/
if (pty_master) {
if (--o_tty->count < 0) {
- printk(KERN_WARNING "tty_release_dev: bad pty slave count "
- "(%d) for %s\n",
- o_tty->count, tty_name(o_tty, buf));
+ printk(KERN_WARNING "%s: bad pty slave count (%d) for %s\n",
+ __func__, o_tty->count, tty_name(o_tty, buf));
o_tty->count = 0;
}
}
if (--tty->count < 0) {
- printk(KERN_WARNING "tty_release_dev: bad tty->count (%d) for %s\n",
- tty->count, tty_name(tty, buf));
+ printk(KERN_WARNING "%s: bad tty->count (%d) for %s\n",
+ __func__, tty->count, tty_name(tty, buf));
tty->count = 0;
}
@@ -1742,34 +1846,125 @@ int tty_release(struct inode *inode, struct file *filp)
}
mutex_unlock(&tty_mutex);
+ tty_unlock_pair(tty, o_tty);
+ /* At this point the TTY_CLOSING flag should ensure a dead tty
+ cannot be re-opened by a racing opener */
/* check whether both sides are closing ... */
- if (!tty_closing || (o_tty && !o_tty_closing)) {
- tty_unlock();
+ if (!tty_closing || (o_tty && !o_tty_closing))
return 0;
- }
#ifdef TTY_DEBUG_HANGUP
- printk(KERN_DEBUG "freeing tty structure...");
+ printk(KERN_DEBUG "%s: %s: final close\n", __func__, tty_name(tty, buf));
#endif
/*
* Ask the line discipline code to release its structures
*/
tty_ldisc_release(tty, o_tty);
+
+ /* Wait for pending work before tty destruction commmences */
+ tty_flush_works(tty);
+ if (o_tty)
+ tty_flush_works(o_tty);
+
+#ifdef TTY_DEBUG_HANGUP
+ printk(KERN_DEBUG "%s: %s: freeing structure...\n", __func__, tty_name(tty, buf));
+#endif
/*
* The release_tty function takes care of the details of clearing
- * the slots and preserving the termios structure.
+ * the slots and preserving the termios structure. The tty_unlock_pair
+ * should be safe as we keep a kref while the tty is locked (so the
+ * unlock never unlocks a freed tty).
*/
+ mutex_lock(&tty_mutex);
release_tty(tty, idx);
+ mutex_unlock(&tty_mutex);
- /* Make this pty number available for reallocation */
- if (devpts)
- devpts_kill_index(inode, idx);
- tty_unlock();
return 0;
}
/**
+ * tty_open_current_tty - get tty of current task for open
+ * @device: device number
+ * @filp: file pointer to tty
+ * @return: tty of the current task iff @device is /dev/tty
+ *
+ * We cannot return driver and index like for the other nodes because
+ * devpts will not work then. It expects inodes to be from devpts FS.
+ *
+ * We need to move to returning a refcounted object from all the lookup
+ * paths including this one.
+ */
+static struct tty_struct *tty_open_current_tty(dev_t device, struct file *filp)
+{
+ struct tty_struct *tty;
+
+ if (device != MKDEV(TTYAUX_MAJOR, 0))
+ return NULL;
+
+ tty = get_current_tty();
+ if (!tty)
+ return ERR_PTR(-ENXIO);
+
+ filp->f_flags |= O_NONBLOCK; /* Don't let /dev/tty block */
+ /* noctty = 1; */
+ tty_kref_put(tty);
+ /* FIXME: we put a reference and return a TTY! */
+ /* This is only safe because the caller holds tty_mutex */
+ return tty;
+}
+
+/**
+ * tty_lookup_driver - lookup a tty driver for a given device file
+ * @device: device number
+ * @filp: file pointer to tty
+ * @noctty: set if the device should not become a controlling tty
+ * @index: index for the device in the @return driver
+ * @return: driver for this inode (with increased refcount)
+ *
+ * If @return is not erroneous, the caller is responsible to decrement the
+ * refcount by tty_driver_kref_put.
+ *
+ * Locking: tty_mutex protects get_tty_driver
+ */
+static struct tty_driver *tty_lookup_driver(dev_t device, struct file *filp,
+ int *noctty, int *index)
+{
+ struct tty_driver *driver;
+
+ switch (device) {
+#ifdef CONFIG_VT
+ case MKDEV(TTY_MAJOR, 0): {
+ extern struct tty_driver *console_driver;
+ driver = tty_driver_kref_get(console_driver);
+ *index = fg_console;
+ *noctty = 1;
+ break;
+ }
+#endif
+ case MKDEV(TTYAUX_MAJOR, 1): {
+ struct tty_driver *console_driver = console_device(index);
+ if (console_driver) {
+ driver = tty_driver_kref_get(console_driver);
+ if (driver) {
+ /* Don't let /dev/console block */
+ filp->f_flags |= O_NONBLOCK;
+ *noctty = 1;
+ break;
+ }
+ }
+ return ERR_PTR(-ENODEV);
+ }
+ default:
+ driver = get_tty_driver(device, index);
+ if (!driver)
+ return ERR_PTR(-ENODEV);
+ break;
+ }
+ return driver;
+}
+
+/**
* tty_open - open a tty device
* @inode: inode of device file
* @filp: file pointer to tty
@@ -1785,16 +1980,19 @@ int tty_release(struct inode *inode, struct file *filp)
* The termios state of a pty is reset on first open so that
* settings don't persist across reuse.
*
- * Locking: tty_mutex protects tty, get_tty_driver and tty_init_dev work.
+ * Locking: tty_mutex protects tty, tty_lookup_driver and tty_init_dev.
* tty->count should protect the rest.
* ->siglock protects ->signal/->sighand
+ *
+ * Note: the tty_unlock/lock cases without a ref are only safe due to
+ * tty_mutex
*/
static int tty_open(struct inode *inode, struct file *filp)
{
- struct tty_struct *tty = NULL;
+ struct tty_struct *tty;
int noctty, retval;
- struct tty_driver *driver;
+ struct tty_driver *driver = NULL;
int index;
dev_t device = inode->i_rdev;
unsigned saved_flags = filp->f_flags;
@@ -1802,104 +2000,66 @@ static int tty_open(struct inode *inode, struct file *filp)
nonseekable_open(inode, filp);
retry_open:
+ retval = tty_alloc_file(filp);
+ if (retval)
+ return -ENOMEM;
+
noctty = filp->f_flags & O_NOCTTY;
index = -1;
retval = 0;
mutex_lock(&tty_mutex);
- tty_lock();
-
- if (device == MKDEV(TTYAUX_MAJOR, 0)) {
- tty = get_current_tty();
- if (!tty) {
- tty_unlock();
- mutex_unlock(&tty_mutex);
- return -ENXIO;
- }
- driver = tty_driver_kref_get(tty->driver);
- index = tty->index;
- filp->f_flags |= O_NONBLOCK; /* Don't let /dev/tty block */
- /* noctty = 1; */
- /* FIXME: Should we take a driver reference ? */
- tty_kref_put(tty);
- goto got_driver;
- }
-#ifdef CONFIG_VT
- if (device == MKDEV(TTY_MAJOR, 0)) {
- extern struct tty_driver *console_driver;
- driver = tty_driver_kref_get(console_driver);
- index = fg_console;
- noctty = 1;
- goto got_driver;
- }
-#endif
- if (device == MKDEV(TTYAUX_MAJOR, 1)) {
- struct tty_driver *console_driver = console_device(&index);
- if (console_driver) {
- driver = tty_driver_kref_get(console_driver);
- if (driver) {
- /* Don't let /dev/console block */
- filp->f_flags |= O_NONBLOCK;
- noctty = 1;
- goto got_driver;
- }
+ /* This is protected by the tty_mutex */
+ tty = tty_open_current_tty(device, filp);
+ if (IS_ERR(tty)) {
+ retval = PTR_ERR(tty);
+ goto err_unlock;
+ } else if (!tty) {
+ driver = tty_lookup_driver(device, filp, &noctty, &index);
+ if (IS_ERR(driver)) {
+ retval = PTR_ERR(driver);
+ goto err_unlock;
}
- tty_unlock();
- mutex_unlock(&tty_mutex);
- return -ENODEV;
- }
- driver = get_tty_driver(device, &index);
- if (!driver) {
- tty_unlock();
- mutex_unlock(&tty_mutex);
- return -ENODEV;
- }
-got_driver:
- if (!tty) {
/* check whether we're reopening an existing tty */
tty = tty_driver_lookup_tty(driver, inode, index);
-
if (IS_ERR(tty)) {
- tty_unlock();
- mutex_unlock(&tty_mutex);
- return PTR_ERR(tty);
+ retval = PTR_ERR(tty);
+ goto err_unlock;
}
}
if (tty) {
+ tty_lock(tty);
retval = tty_reopen(tty);
- if (retval)
+ if (retval < 0) {
+ tty_unlock(tty);
tty = ERR_PTR(retval);
- } else
- tty = tty_init_dev(driver, index, 0);
+ }
+ } else /* Returns with the tty_lock held for now */
+ tty = tty_init_dev(driver, index);
mutex_unlock(&tty_mutex);
- tty_driver_kref_put(driver);
+ if (driver)
+ tty_driver_kref_put(driver);
if (IS_ERR(tty)) {
- tty_unlock();
- return PTR_ERR(tty);
+ retval = PTR_ERR(tty);
+ goto err_file;
}
- retval = tty_add_file(tty, filp);
- if (retval) {
- tty_unlock();
- return retval;
- }
+ tty_add_file(tty, filp);
- check_tty_count(tty, "tty_open");
+ check_tty_count(tty, __func__);
if (tty->driver->type == TTY_DRIVER_TYPE_PTY &&
tty->driver->subtype == PTY_TYPE_MASTER)
noctty = 1;
#ifdef TTY_DEBUG_HANGUP
- printk(KERN_DEBUG "opening %s...", tty->name);
+ printk(KERN_DEBUG "%s: opening %s...\n", __func__, tty->name);
#endif
- if (!retval) {
- if (tty->ops->open)
- retval = tty->ops->open(tty, filp);
- else
- retval = -ENODEV;
- }
+ if (tty->ops->open)
+ retval = tty->ops->open(tty, filp);
+ else
+ retval = -ENODEV;
filp->f_flags = saved_flags;
if (!retval && test_bit(TTY_EXCLUSIVE, &tty->flags) &&
@@ -1908,10 +2068,10 @@ got_driver:
if (retval) {
#ifdef TTY_DEBUG_HANGUP
- printk(KERN_DEBUG "error %d in opening %s...", retval,
- tty->name);
+ printk(KERN_DEBUG "%s: error %d in opening %s...\n", __func__,
+ retval, tty->name);
#endif
- tty_unlock(); /* need to call tty_release without BTM */
+ tty_unlock(tty); /* need to call tty_release without BTM */
tty_release(inode, filp);
if (retval != -ERESTARTSYS)
return retval;
@@ -1923,17 +2083,16 @@ got_driver:
/*
* Need to reset f_op in case a hangup happened.
*/
- tty_lock();
if (filp->f_op == &hung_up_tty_fops)
filp->f_op = &tty_fops;
- tty_unlock();
goto retry_open;
}
- tty_unlock();
+ clear_bit(TTY_HUPPED, &tty->flags);
+ tty_unlock(tty);
mutex_lock(&tty_mutex);
- tty_lock();
+ tty_lock(tty);
spin_lock_irq(&current->sighand->siglock);
if (!noctty &&
current->signal->leader &&
@@ -1941,9 +2100,17 @@ got_driver:
tty->session == NULL)
__proc_set_tty(current, tty);
spin_unlock_irq(&current->sighand->siglock);
- tty_unlock();
+ tty_unlock(tty);
mutex_unlock(&tty_mutex);
return 0;
+err_unlock:
+ mutex_unlock(&tty_mutex);
+ /* after locks to avoid deadlock */
+ if (!IS_ERR_OR_NULL(driver))
+ tty_driver_kref_put(driver);
+err_file:
+ tty_free_file(filp);
+ return retval;
}
@@ -1966,7 +2133,7 @@ static unsigned int tty_poll(struct file *filp, poll_table *wait)
struct tty_ldisc *ld;
int ret = 0;
- if (tty_paranoia_check(tty, filp->f_path.dentry->d_inode, "tty_poll"))
+ if (tty_paranoia_check(tty, file_inode(filp), "tty_poll"))
return 0;
ld = tty_ldisc_ref_wait(tty);
@@ -1979,21 +2146,28 @@ 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 = file_tty(filp);
+ struct tty_ldisc *ldisc;
unsigned long flags;
int retval = 0;
- if (tty_paranoia_check(tty, filp->f_path.dentry->d_inode, "tty_fasync"))
+ if (tty_paranoia_check(tty, file_inode(filp), "tty_fasync"))
goto out;
retval = fasync_helper(fd, filp, on, &tty->fasync);
if (retval <= 0)
goto out;
+ ldisc = tty_ldisc_ref(tty);
+ if (ldisc) {
+ if (ldisc->ops->fasync)
+ ldisc->ops->fasync(tty, on);
+ tty_ldisc_deref(ldisc);
+ }
+
if (on) {
enum pid_type type;
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;
@@ -2006,23 +2180,20 @@ static int __tty_fasync(int fd, struct file *filp, int on)
spin_unlock_irqrestore(&tty->ctrl_lock, flags);
retval = __f_setown(filp, pid, type, 0);
put_pid(pid);
- if (retval)
- goto out;
- } else {
- if (!tty->fasync && !waitqueue_active(&tty->read_wait))
- tty->minimum_to_wake = N_TTY_BUF_SIZE;
}
- retval = 0;
out:
return retval;
}
static int tty_fasync(int fd, struct file *filp, int on)
{
+ struct tty_struct *tty = file_tty(filp);
int retval;
- tty_lock();
+
+ tty_lock(tty);
retval = __tty_fasync(fd, filp, on);
- tty_unlock();
+ tty_unlock(tty);
+
return retval;
}
@@ -2037,7 +2208,7 @@ static int tty_fasync(int fd, struct file *filp, int on)
* FIXME: does not honour flow control ??
*
* Locking:
- * Called functions take tty_ldisc_lock
+ * Called functions take tty_ldiscs_lock
* current->signal->tty check is safe without locks
*
* FIXME: may race normal receive processing
@@ -2066,7 +2237,7 @@ static int tiocsti(struct tty_struct *tty, char __user *p)
*
* Copies the kernel idea of the window size into the user buffer.
*
- * Locking: tty->termios_mutex is taken to ensure the winsize data
+ * Locking: tty->winsize_mutex is taken to ensure the winsize data
* is consistent.
*/
@@ -2074,9 +2245,9 @@ static int tiocgwinsz(struct tty_struct *tty, struct winsize __user *arg)
{
int err;
- mutex_lock(&tty->termios_mutex);
+ mutex_lock(&tty->winsize_mutex);
err = copy_to_user(arg, &tty->winsize, sizeof(*arg));
- mutex_unlock(&tty->termios_mutex);
+ mutex_unlock(&tty->winsize_mutex);
return err ? -EFAULT: 0;
}
@@ -2097,7 +2268,7 @@ int tty_do_resize(struct tty_struct *tty, struct winsize *ws)
unsigned long flags;
/* Lock the tty */
- mutex_lock(&tty->termios_mutex);
+ mutex_lock(&tty->winsize_mutex);
if (!memcmp(ws, &tty->winsize, sizeof(*ws)))
goto done;
/* Get the PID values and reference them so we can
@@ -2112,9 +2283,10 @@ int tty_do_resize(struct tty_struct *tty, struct winsize *ws)
tty->winsize = *ws;
done:
- mutex_unlock(&tty->termios_mutex);
+ mutex_unlock(&tty->winsize_mutex);
return 0;
}
+EXPORT_SYMBOL(tty_do_resize);
/**
* tiocswinsz - implement window size set ioctl
@@ -2126,7 +2298,7 @@ done:
* actually has driver level meaning and triggers a VC resize.
*
* Locking:
- * Driver dependant. The default do_resize method takes the
+ * Driver dependent. The default do_resize method takes the
* tty termios mutex and ctrl_lock. The console takes its own lock
* then calls into the default method.
*/
@@ -2147,7 +2319,7 @@ static int tiocswinsz(struct tty_struct *tty, struct winsize __user *arg)
* tioccons - allow admin to move logical console
* @file: the file to become console
*
- * Allow the adminstrator to move the redirected console device
+ * Allow the administrator to move the redirected console device
*
* Locking: uses redirect_lock to guard the redirect information
*/
@@ -2171,8 +2343,7 @@ static int tioccons(struct file *file)
spin_unlock(&redirect_lock);
return -EBUSY;
}
- get_file(file);
- redirect = file;
+ redirect = get_file(file);
spin_unlock(&redirect_lock);
return 0;
}
@@ -2282,7 +2453,7 @@ 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
+ * @real_tty: tty side of the tty passed by the user if a pty else the tty
* @p: returned pid
*
* Obtain the process group of the tty. If there is no process group
@@ -2359,7 +2530,7 @@ out_unlock:
/**
* tiocgsid - get session id
* @tty: tty passed by user
- * @real_tty: tty side of the tty pased by the user if a pty else the tty
+ * @real_tty: tty side of the tty passed by the user if a pty else the tty
* @p: pointer to returned session id
*
* Obtain the session id of the tty. If there is no session
@@ -2456,12 +2627,12 @@ out:
* Locking: none (up to the driver)
*/
-static int tty_tiocmget(struct tty_struct *tty, struct file *file, int __user *p)
+static int tty_tiocmget(struct tty_struct *tty, int __user *p)
{
int retval = -EINVAL;
if (tty->ops->tiocmget) {
- retval = tty->ops->tiocmget(tty, file);
+ retval = tty->ops->tiocmget(tty);
if (retval >= 0)
retval = put_user(retval, p);
@@ -2472,7 +2643,6 @@ static int tty_tiocmget(struct tty_struct *tty, struct file *file, int __user *p
/**
* tty_tiocmset - set modem status
* @tty: tty device
- * @file: user file pointer
* @cmd: command - clear bits, set bits or set all
* @p: pointer to desired bits
*
@@ -2482,7 +2652,7 @@ static int tty_tiocmget(struct tty_struct *tty, struct file *file, int __user *p
* Locking: none (up to the driver)
*/
-static int tty_tiocmset(struct tty_struct *tty, struct file *file, unsigned int cmd,
+static int tty_tiocmset(struct tty_struct *tty, unsigned int cmd,
unsigned __user *p)
{
int retval;
@@ -2509,7 +2679,7 @@ 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;
- return tty->ops->tiocmset(tty, file, set, clear);
+ return tty->ops->tiocmset(tty, set, clear);
}
static int tty_tiocgicount(struct tty_struct *tty, void __user *arg)
@@ -2554,9 +2724,8 @@ long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
void __user *p = (void __user *)arg;
int retval;
struct tty_ldisc *ld;
- struct inode *inode = file->f_dentry->d_inode;
- if (tty_paranoia_check(tty, inode, "tty_ioctl"))
+ if (tty_paranoia_check(tty, file_inode(file), "tty_ioctl"))
return -EINVAL;
real_tty = tty_pair_get_tty(tty);
@@ -2601,6 +2770,11 @@ long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
case TIOCNXCL:
clear_bit(TTY_EXCLUSIVE, &tty->flags);
return 0;
+ case TIOCGEXCL:
+ {
+ int excl = test_bit(TTY_EXCLUSIVE, &tty->flags);
+ return put_user(excl, (int __user *)p);
+ }
case TIOCNOTTY:
if (current->signal->tty != tty)
return -ENOTTY;
@@ -2618,6 +2792,16 @@ long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
return put_user(tty->ldisc->ops->num, (int __user *)p);
case TIOCSETD:
return tiocsetd(tty, p);
+ case TIOCVHANGUP:
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+ tty_vhangup(tty);
+ return 0;
+ case TIOCGDEV:
+ {
+ unsigned int ret = new_encode_dev(tty_devnum(real_tty));
+ return put_user(ret, (unsigned int __user *)p);
+ }
/*
* Break handling
*/
@@ -2641,11 +2825,11 @@ long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
return send_break(tty, arg ? arg*100 : 250);
case TIOCMGET:
- return tty_tiocmget(tty, file, p);
+ return tty_tiocmget(tty, p);
case TIOCMSET:
case TIOCMBIC:
case TIOCMBIS:
- return tty_tiocmset(tty, file, cmd, p);
+ return tty_tiocmset(tty, cmd, p);
case TIOCGICOUNT:
retval = tty_tiocgicount(tty, p);
/* For the moment allow fall through to the old method */
@@ -2663,7 +2847,7 @@ long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
break;
}
if (tty->ops->ioctl) {
- retval = (tty->ops->ioctl)(tty, file, cmd, arg);
+ retval = (tty->ops->ioctl)(tty, cmd, arg);
if (retval != -ENOIOCTLCMD)
return retval;
}
@@ -2672,7 +2856,7 @@ long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
if (ld->ops->ioctl) {
retval = ld->ops->ioctl(tty, file, cmd, arg);
if (retval == -ENOIOCTLCMD)
- retval = -EINVAL;
+ retval = -ENOTTY;
}
tty_ldisc_deref(ld);
return retval;
@@ -2682,16 +2866,15 @@ long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
static long tty_compat_ioctl(struct file *file, unsigned int cmd,
unsigned long arg)
{
- struct inode *inode = file->f_dentry->d_inode;
struct tty_struct *tty = file_tty(file);
struct tty_ldisc *ld;
int retval = -ENOIOCTLCMD;
- if (tty_paranoia_check(tty, inode, "tty_ioctl"))
+ if (tty_paranoia_check(tty, file_inode(file), "tty_ioctl"))
return -EINVAL;
if (tty->ops->compat_ioctl) {
- retval = (tty->ops->compat_ioctl)(tty, file, cmd, arg);
+ retval = (tty->ops->compat_ioctl)(tty, cmd, arg);
if (retval != -ENOIOCTLCMD)
return retval;
}
@@ -2699,12 +2882,21 @@ static long tty_compat_ioctl(struct file *file, unsigned int cmd,
ld = tty_ldisc_ref_wait(tty);
if (ld->ops->compat_ioctl)
retval = ld->ops->compat_ioctl(tty, file, cmd, arg);
+ else
+ retval = n_tty_compat_ioctl_helper(tty, file, cmd, arg);
tty_ldisc_deref(ld);
return retval;
}
#endif
+static int this_tty(const void *t, struct file *file, unsigned fd)
+{
+ if (likely(file->f_op->read != tty_read))
+ return 0;
+ return file_tty(file) != t ? 0 : fd + 1;
+}
+
/*
* This implements the "Secure Attention Key" --- the idea is to
* prevent trojan horses by killing all processes associated with this
@@ -2732,8 +2924,6 @@ void __do_SAK(struct tty_struct *tty)
struct task_struct *g, *p;
struct pid *session;
int i;
- struct file *filp;
- struct fdtable *fdt;
if (!tty)
return;
@@ -2763,27 +2953,12 @@ void __do_SAK(struct tty_struct *tty)
continue;
}
task_lock(p);
- if (p->files) {
- /*
- * We don't take a ref to the file, so we must
- * hold ->file_lock instead.
- */
- spin_lock(&p->files->file_lock);
- fdt = files_fdtable(p->files);
- for (i = 0; i < fdt->max_fds; i++) {
- filp = fcheck_files(p->files, i);
- if (!filp)
- continue;
- if (filp->f_op->read == tty_read &&
- file_tty(filp) == tty) {
- printk(KERN_NOTICE "SAK: killed process %d"
- " (%s): fd#%d opened to the tty\n",
- task_pid_nr(p), p->comm, i);
- force_sig(SIGKILL, p);
- break;
- }
- }
- spin_unlock(&p->files->file_lock);
+ i = iterate_fd(p->files, 0, this_tty, tty);
+ if (i != 0) {
+ printk(KERN_NOTICE "SAK: killed process %d"
+ " (%s): fd#%d opened to the tty\n",
+ task_pid_nr(p), p->comm, i - 1);
+ force_sig(SIGKILL, p);
}
task_unlock(p);
} while_each_thread(g, p);
@@ -2813,9 +2988,9 @@ void do_SAK(struct tty_struct *tty)
EXPORT_SYMBOL(do_SAK);
-static int dev_match_devt(struct device *dev, void *data)
+static int dev_match_devt(struct device *dev, const void *data)
{
- dev_t *devt = data;
+ const dev_t *devt = data;
return dev->devt == *devt;
}
@@ -2846,19 +3021,15 @@ void initialize_tty_struct(struct tty_struct *tty,
tty_ldisc_init(tty);
tty->session = NULL;
tty->pgrp = NULL;
- tty->overrun_time = jiffies;
- tty->buf.head = tty->buf.tail = NULL;
- tty_buffer_init(tty);
- mutex_init(&tty->termios_mutex);
- mutex_init(&tty->ldisc_mutex);
+ mutex_init(&tty->legacy_mutex);
+ mutex_init(&tty->throttle_mutex);
+ init_rwsem(&tty->termios_rwsem);
+ mutex_init(&tty->winsize_mutex);
+ init_ldsem(&tty->ldisc_sem);
init_waitqueue_head(&tty->write_wait);
init_waitqueue_head(&tty->read_wait);
INIT_WORK(&tty->hangup_work, do_tty_hangup);
- mutex_init(&tty->atomic_read_lock);
mutex_init(&tty->atomic_write_lock);
- mutex_init(&tty->output_lock);
- mutex_init(&tty->echo_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);
@@ -2871,6 +3042,20 @@ void initialize_tty_struct(struct tty_struct *tty,
}
/**
+ * deinitialize_tty_struct
+ * @tty: tty to deinitialize
+ *
+ * This subroutine deinitializes a tty structure that has been newly
+ * allocated but tty_release cannot be called on that yet.
+ *
+ * Locking: none - tty in question must not be exposed at this point
+ */
+void deinitialize_tty_struct(struct tty_struct *tty)
+{
+ tty_ldisc_deinit(tty);
+}
+
+/**
* tty_put_char - write one character to a tty
* @tty: tty
* @ch: character
@@ -2892,6 +3077,15 @@ EXPORT_SYMBOL_GPL(tty_put_char);
struct class *tty_class;
+static int tty_cdev_add(struct tty_driver *driver, dev_t dev,
+ unsigned int index, unsigned int count)
+{
+ /* init here, since reused cdevs cause crashes */
+ cdev_init(&driver->cdevs[index], &tty_fops);
+ driver->cdevs[index].owner = driver->owner;
+ return cdev_add(&driver->cdevs[index], dev, count);
+}
+
/**
* tty_register_device - register a tty device
* @driver: the tty driver that describes the tty device
@@ -2914,8 +3108,46 @@ struct class *tty_class;
struct device *tty_register_device(struct tty_driver *driver, unsigned index,
struct device *device)
{
+ return tty_register_device_attr(driver, index, device, NULL, NULL);
+}
+EXPORT_SYMBOL(tty_register_device);
+
+static void tty_device_create_release(struct device *dev)
+{
+ pr_debug("device: '%s': %s\n", dev_name(dev), __func__);
+ kfree(dev);
+}
+
+/**
+ * tty_register_device_attr - register a tty device
+ * @driver: the tty driver that describes the tty device
+ * @index: the index in the tty driver for this tty device
+ * @device: a struct device that is associated with this tty device.
+ * This field is optional, if there is no known struct device
+ * for this tty device it can be set to NULL safely.
+ * @drvdata: Driver data to be set to device.
+ * @attr_grp: Attribute group to be set on device.
+ *
+ * Returns a pointer to the struct device for this tty device
+ * (or ERR_PTR(-EFOO) on error).
+ *
+ * This call is required to be made to register an individual tty device
+ * if the tty driver's flags have the TTY_DRIVER_DYNAMIC_DEV bit set. If
+ * that bit is not set, this function should not be called by a tty
+ * driver.
+ *
+ * Locking: ??
+ */
+struct device *tty_register_device_attr(struct tty_driver *driver,
+ unsigned index, struct device *device,
+ void *drvdata,
+ const struct attribute_group **attr_grp)
+{
char name[64];
- dev_t dev = MKDEV(driver->major, driver->minor_start) + index;
+ dev_t devt = MKDEV(driver->major, driver->minor_start) + index;
+ struct device *dev = NULL;
+ int retval = -ENODEV;
+ bool cdev = false;
if (index >= driver->num) {
printk(KERN_ERR "Attempt to register invalid tty line number "
@@ -2928,9 +3160,40 @@ struct device *tty_register_device(struct tty_driver *driver, unsigned index,
else
tty_line_name(driver, index, name);
- return device_create(tty_class, device, dev, NULL, name);
+ if (!(driver->flags & TTY_DRIVER_DYNAMIC_ALLOC)) {
+ retval = tty_cdev_add(driver, devt, index, 1);
+ if (retval)
+ goto error;
+ cdev = true;
+ }
+
+ dev = kzalloc(sizeof(*dev), GFP_KERNEL);
+ if (!dev) {
+ retval = -ENOMEM;
+ goto error;
+ }
+
+ dev->devt = devt;
+ dev->class = tty_class;
+ dev->parent = device;
+ dev->release = tty_device_create_release;
+ dev_set_name(dev, "%s", name);
+ dev->groups = attr_grp;
+ dev_set_drvdata(dev, drvdata);
+
+ retval = device_register(dev);
+ if (retval)
+ goto error;
+
+ return dev;
+
+error:
+ put_device(dev);
+ if (cdev)
+ cdev_del(&driver->cdevs[index]);
+ return ERR_PTR(retval);
}
-EXPORT_SYMBOL(tty_register_device);
+EXPORT_SYMBOL_GPL(tty_register_device_attr);
/**
* tty_unregister_device - unregister a tty device
@@ -2947,30 +3210,82 @@ void tty_unregister_device(struct tty_driver *driver, unsigned index)
{
device_destroy(tty_class,
MKDEV(driver->major, driver->minor_start) + index);
+ if (!(driver->flags & TTY_DRIVER_DYNAMIC_ALLOC))
+ cdev_del(&driver->cdevs[index]);
}
EXPORT_SYMBOL(tty_unregister_device);
-struct tty_driver *alloc_tty_driver(int lines)
+/**
+ * __tty_alloc_driver -- allocate tty driver
+ * @lines: count of lines this driver can handle at most
+ * @owner: module which is repsonsible for this driver
+ * @flags: some of TTY_DRIVER_* flags, will be set in driver->flags
+ *
+ * This should not be called directly, some of the provided macros should be
+ * used instead. Use IS_ERR and friends on @retval.
+ */
+struct tty_driver *__tty_alloc_driver(unsigned int lines, struct module *owner,
+ unsigned long flags)
{
struct tty_driver *driver;
+ unsigned int cdevs = 1;
+ int err;
+
+ if (!lines || (flags & TTY_DRIVER_UNNUMBERED_NODE && lines > 1))
+ return ERR_PTR(-EINVAL);
driver = kzalloc(sizeof(struct tty_driver), GFP_KERNEL);
- if (driver) {
- kref_init(&driver->kref);
- driver->magic = TTY_DRIVER_MAGIC;
- driver->num = lines;
- /* later we'll move allocation of tables here */
+ if (!driver)
+ return ERR_PTR(-ENOMEM);
+
+ kref_init(&driver->kref);
+ driver->magic = TTY_DRIVER_MAGIC;
+ driver->num = lines;
+ driver->owner = owner;
+ driver->flags = flags;
+
+ if (!(flags & TTY_DRIVER_DEVPTS_MEM)) {
+ driver->ttys = kcalloc(lines, sizeof(*driver->ttys),
+ GFP_KERNEL);
+ driver->termios = kcalloc(lines, sizeof(*driver->termios),
+ GFP_KERNEL);
+ if (!driver->ttys || !driver->termios) {
+ err = -ENOMEM;
+ goto err_free_all;
+ }
+ }
+
+ if (!(flags & TTY_DRIVER_DYNAMIC_ALLOC)) {
+ driver->ports = kcalloc(lines, sizeof(*driver->ports),
+ GFP_KERNEL);
+ if (!driver->ports) {
+ err = -ENOMEM;
+ goto err_free_all;
+ }
+ cdevs = lines;
}
+
+ driver->cdevs = kcalloc(cdevs, sizeof(*driver->cdevs), GFP_KERNEL);
+ if (!driver->cdevs) {
+ err = -ENOMEM;
+ goto err_free_all;
+ }
+
return driver;
+err_free_all:
+ kfree(driver->ports);
+ kfree(driver->ttys);
+ kfree(driver->termios);
+ kfree(driver);
+ return ERR_PTR(err);
}
-EXPORT_SYMBOL(alloc_tty_driver);
+EXPORT_SYMBOL(__tty_alloc_driver);
static void destruct_tty_driver(struct kref *kref)
{
struct tty_driver *driver = container_of(kref, struct tty_driver, kref);
int i;
struct ktermios *tp;
- void *p;
if (driver->flags & TTY_DRIVER_INSTALLED) {
/*
@@ -2987,13 +3302,14 @@ static void destruct_tty_driver(struct kref *kref)
if (!(driver->flags & TTY_DRIVER_DYNAMIC_DEV))
tty_unregister_device(driver, i);
}
- p = driver->ttys;
proc_tty_unregister_driver(driver);
- driver->ttys = NULL;
- driver->termios = NULL;
- kfree(p);
- cdev_del(&driver->cdev);
+ if (driver->flags & TTY_DRIVER_DYNAMIC_ALLOC)
+ cdev_del(&driver->cdevs[0]);
}
+ kfree(driver->cdevs);
+ kfree(driver->ports);
+ kfree(driver->termios);
+ kfree(driver->ttys);
kfree(driver);
}
@@ -3024,15 +3340,8 @@ int tty_register_driver(struct tty_driver *driver)
int error;
int i;
dev_t dev;
- void **p = NULL;
struct device *d;
- if (!(driver->flags & TTY_DRIVER_DEVPTS_MEM) && driver->num) {
- p = kzalloc(driver->num * 2 * sizeof(void *), GFP_KERNEL);
- if (!p)
- return -ENOMEM;
- }
-
if (!driver->major) {
error = alloc_chrdev_region(&dev, driver->minor_start,
driver->num, driver->name);
@@ -3044,28 +3353,13 @@ int tty_register_driver(struct tty_driver *driver)
dev = MKDEV(driver->major, driver->minor_start);
error = register_chrdev_region(dev, driver->num, driver->name);
}
- if (error < 0) {
- kfree(p);
- return error;
- }
+ if (error < 0)
+ goto err;
- if (p) {
- driver->ttys = (struct tty_struct **)p;
- driver->termios = (struct ktermios **)(p + driver->num);
- } else {
- driver->ttys = NULL;
- driver->termios = NULL;
- }
-
- cdev_init(&driver->cdev, &tty_fops);
- driver->cdev.owner = driver->owner;
- error = cdev_add(&driver->cdev, dev, driver->num);
- if (error) {
- unregister_chrdev_region(dev, driver->num);
- driver->ttys = NULL;
- driver->termios = NULL;
- kfree(p);
- return error;
+ if (driver->flags & TTY_DRIVER_DYNAMIC_ALLOC) {
+ error = tty_cdev_add(driver, dev, 0, driver->num);
+ if (error)
+ goto err_unreg_char;
}
mutex_lock(&tty_mutex);
@@ -3077,7 +3371,7 @@ int tty_register_driver(struct tty_driver *driver)
d = tty_register_device(driver, i, NULL);
if (IS_ERR(d)) {
error = PTR_ERR(d);
- goto err;
+ goto err_unreg_devs;
}
}
}
@@ -3085,7 +3379,7 @@ int tty_register_driver(struct tty_driver *driver)
driver->flags |= TTY_DRIVER_INSTALLED;
return 0;
-err:
+err_unreg_devs:
for (i--; i >= 0; i--)
tty_unregister_device(driver, i);
@@ -3093,13 +3387,11 @@ err:
list_del(&driver->tty_drivers);
mutex_unlock(&tty_mutex);
+err_unreg_char:
unregister_chrdev_region(dev, driver->num);
- driver->ttys = NULL;
- driver->termios = NULL;
- kfree(p);
+err:
return error;
}
-
EXPORT_SYMBOL(tty_register_driver);
/*
@@ -3210,7 +3502,7 @@ void __init console_init(void)
}
}
-static char *tty_devnode(struct device *dev, mode_t *mode)
+static char *tty_devnode(struct device *dev, umode_t *mode)
{
if (!mode)
return NULL;
@@ -3232,9 +3524,55 @@ static int __init tty_class_init(void)
postcore_initcall(tty_class_init);
/* 3/2004 jmc: why do these devices exist? */
-
static struct cdev tty_cdev, console_cdev;
+static ssize_t show_cons_active(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct console *cs[16];
+ int i = 0;
+ struct console *c;
+ ssize_t count = 0;
+
+ console_lock();
+ for_each_console(c) {
+ if (!c->device)
+ continue;
+ if (!c->write)
+ continue;
+ if ((c->flags & CON_ENABLED) == 0)
+ continue;
+ cs[i++] = c;
+ if (i >= ARRAY_SIZE(cs))
+ break;
+ }
+ while (i--) {
+ int index = cs[i]->index;
+ struct tty_driver *drv = cs[i]->device(cs[i], &index);
+
+ /* don't resolve tty0 as some programs depend on it */
+ if (drv && (cs[i]->index > 0 || drv->major != TTY_MAJOR))
+ count += tty_line_name(drv, index, buf + count);
+ else
+ count += sprintf(buf + count, "%s%d",
+ cs[i]->name, cs[i]->index);
+
+ count += sprintf(buf + count, "%c", i ? ' ':'\n');
+ }
+ console_unlock();
+
+ return count;
+}
+static DEVICE_ATTR(active, S_IRUGO, show_cons_active, NULL);
+
+static struct device *consdev;
+
+void console_sysfs_notify(void)
+{
+ if (consdev)
+ sysfs_notify(&consdev->kobj, NULL, "active");
+}
+
/*
* Ok, now we can initialize the rest of the tty devices and can count
* on memory allocations, interrupts etc..
@@ -3245,15 +3583,18 @@ int __init tty_init(void)
if (cdev_add(&tty_cdev, MKDEV(TTYAUX_MAJOR, 0), 1) ||
register_chrdev_region(MKDEV(TTYAUX_MAJOR, 0), 1, "/dev/tty") < 0)
panic("Couldn't register /dev/tty driver\n");
- device_create(tty_class, NULL, MKDEV(TTYAUX_MAJOR, 0), NULL,
- "tty");
+ device_create(tty_class, NULL, MKDEV(TTYAUX_MAJOR, 0), NULL, "tty");
cdev_init(&console_cdev, &console_fops);
if (cdev_add(&console_cdev, MKDEV(TTYAUX_MAJOR, 1), 1) ||
register_chrdev_region(MKDEV(TTYAUX_MAJOR, 1), 1, "/dev/console") < 0)
panic("Couldn't register /dev/console driver\n");
- device_create(tty_class, NULL, MKDEV(TTYAUX_MAJOR, 1), NULL,
+ consdev = device_create(tty_class, NULL, MKDEV(TTYAUX_MAJOR, 1), NULL,
"console");
+ if (IS_ERR(consdev))
+ consdev = NULL;
+ else
+ WARN_ON(device_create_file(consdev, &dev_attr_active) < 0);
#ifdef CONFIG_VT
vty_init(&console_fops);
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2025-11-05 01:43:52 +0000