* implement CONFIG_VT and generalize console device interface.
* -- Marko Kohtala <Marko.Kohtala@hut.fi>, March 97
*
- * Rewrote init_dev and release_dev to eliminate races.
+ * Rewrote tty_init_dev and tty_release_dev to eliminate races.
* -- Bill Hawes <whawes@star.net>, June 97
*
* Added devfs support.
DEFINE_MUTEX(tty_mutex);
EXPORT_SYMBOL(tty_mutex);
-#ifdef CONFIG_UNIX98_PTYS
-extern struct tty_driver *ptm_driver; /* Unix98 pty masters; for /dev/ptmx */
-static int ptmx_open(struct inode *, struct file *);
-#endif
-
-static void initialize_tty_struct(struct tty_struct *tty);
-
static ssize_t tty_read(struct file *, char __user *, size_t, loff_t *);
static ssize_t tty_write(struct file *, const char __user *, size_t, loff_t *);
ssize_t redirected_tty_write(struct file *, const char __user *,
* Locking: none
*/
-static struct tty_struct *alloc_tty_struct(void)
+struct tty_struct *alloc_tty_struct(void)
{
return kzalloc(sizeof(struct tty_struct), GFP_KERNEL);
}
* Locking: none. Must be called after tty is definitely unused
*/
-static inline void free_tty_struct(struct tty_struct *tty)
+void free_tty_struct(struct tty_struct *tty)
{
kfree(tty->write_buf);
tty_buffer_free_all(tty);
if (device < base || device >= base + p->num)
continue;
*index = device - base;
- return p;
+ return tty_driver_kref_get(p);
}
return NULL;
}
if (tty_line >= 0 && tty_line <= p->num && p->ops &&
p->ops->poll_init && !p->ops->poll_init(p, tty_line, str)) {
- res = p;
+ res = tty_driver_kref_get(p);
*line = tty_line;
break;
}
.fasync = tty_fasync,
};
-#ifdef CONFIG_UNIX98_PTYS
-static const struct file_operations ptmx_fops = {
- .llseek = no_llseek,
- .read = tty_read,
- .write = tty_write,
- .poll = tty_poll,
- .unlocked_ioctl = tty_ioctl,
- .compat_ioctl = tty_compat_ioctl,
- .open = ptmx_open,
- .release = tty_release,
- .fasync = tty_fasync,
-};
-#endif
-
static const struct file_operations console_fops = {
.llseek = no_llseek,
.read = tty_read,
EXPORT_SYMBOL(tty_vhangup);
/**
+ * tty_vhangup_self - process vhangup for own ctty
+ *
+ * Perform a vhangup on the current controlling tty
+ */
+
+void tty_vhangup_self(void)
+{
+ struct tty_struct *tty;
+
+ tty = get_current_tty();
+ if (tty) {
+ tty_vhangup(tty);
+ tty_kref_put(tty);
+ }
+}
+
+/**
* tty_hung_up_p - was tty hung up
* @filp: file pointer of tty
*
struct pid *tty_pgrp = NULL;
- mutex_lock(&tty_mutex);
tty = get_current_tty();
if (tty) {
tty_pgrp = get_pid(tty->pgrp);
lock_kernel();
- mutex_unlock(&tty_mutex);
- /* XXX: here we race, there is nothing protecting tty */
if (on_exit && tty->driver->type != TTY_DRIVER_TYPE_PTY)
tty_vhangup(tty);
unlock_kernel();
+ tty_kref_put(tty);
} else if (on_exit) {
struct pid *old_pgrp;
spin_lock_irq(¤t->sighand->siglock);
kill_pgrp(old_pgrp, SIGCONT, on_exit);
put_pid(old_pgrp);
}
- mutex_unlock(&tty_mutex);
return;
}
if (tty_pgrp) {
current->signal->tty_old_pgrp = NULL;
spin_unlock_irq(¤t->sighand->siglock);
- mutex_lock(&tty_mutex);
- /* It is possible that do_tty_hangup has free'd this tty */
tty = get_current_tty();
if (tty) {
unsigned long flags;
tty->session = NULL;
tty->pgrp = NULL;
spin_unlock_irqrestore(&tty->ctrl_lock, flags);
+ tty_kref_put(tty);
} else {
#ifdef TTY_DEBUG_HANGUP
printk(KERN_DEBUG "error attempted to write to tty [0x%p]"
" = NULL", tty);
#endif
}
- mutex_unlock(&tty_mutex);
/* Now clear signal->tty under the lock */
read_lock(&tasklist_lock);
return ret;
}
+/**
+ * tty_write_message - write a message to a certain tty, not just the console.
+ * @tty: the destination tty_struct
+ * @msg: the message to write
+ *
+ * This is used for messages that need to be redirected to a specific tty.
+ * We don't put it into the syslog queue right now maybe in the future if
+ * really needed.
+ *
+ * We must still hold the BKL and test the CLOSING flag for the moment.
+ */
+
+void tty_write_message(struct tty_struct *tty, char *msg)
+{
+ lock_kernel();
+ if (tty) {
+ mutex_lock(&tty->atomic_write_lock);
+ if (tty->ops->write && !test_bit(TTY_CLOSING, &tty->flags))
+ tty->ops->write(tty, msg, strlen(msg));
+ tty_write_unlock(tty);
+ }
+ unlock_kernel();
+ return;
+}
+
/**
* tty_write - write method for tty device file
}
/**
- * pty_line_name - generate name for a tty
+ * tty_line_name - generate name for a tty
* @driver: the tty driver in use
* @index: the minor number
* @p: output buffer of at least 7 bytes
}
/**
- * init_dev - initialise a tty device
+ * tty_driver_lookup_tty() - find an existing tty, if any
+ * @driver: the driver for the tty
+ * @idx: the minor number
+ *
+ * Return the tty, if found or ERR_PTR() otherwise.
+ *
+ * Locking: tty_mutex must be held. If tty is found, the mutex must
+ * be held until the 'fast-open' is also done. Will change once we
+ * have refcounting in the driver and per driver locking
+ */
+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;
+}
+
+/**
+ * tty_init_termios - helper for termios setup
+ * @tty: the tty to set up
+ *
+ * Initialise the termios structures for this tty. Thus runs under
+ * the tty_mutex currently so we can be relaxed about ordering.
+ */
+
+int tty_init_termios(struct tty_struct *tty)
+{
+ struct ktermios *tp, *ltp;
+ int idx = tty->index;
+
+ tp = tty->driver->termios[idx];
+ ltp = tty->driver->termios_locked[idx];
+ if (tp == NULL) {
+ WARN_ON(ltp != NULL);
+ tp = kmalloc(sizeof(struct ktermios), GFP_KERNEL);
+ ltp = kzalloc(sizeof(struct ktermios), GFP_KERNEL);
+ if (tp == NULL || ltp == NULL) {
+ kfree(tp);
+ kfree(ltp);
+ return -ENOMEM;
+ }
+ memcpy(tp, &tty->driver->init_termios,
+ sizeof(struct ktermios));
+ tty->driver->termios[idx] = tp;
+ tty->driver->termios_locked[idx] = ltp;
+ }
+ tty->termios = tp;
+ tty->termios_locked = ltp;
+
+ /* 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);
+ return 0;
+}
+
+/**
+ * tty_driver_install_tty() - install a tty entry in the driver
+ * @driver: the driver for the tty
+ * @tty: the tty
+ *
+ * Install a tty object into the driver tables. The tty->index field
+ * will be set by the time this is called. This method is responsible
+ * for ensuring any need additional structures are allocated and
+ * configured.
+ *
+ * Locking: tty_mutex for now
+ */
+static int tty_driver_install_tty(struct tty_driver *driver,
+ struct tty_struct *tty)
+{
+ int idx = tty->index;
+
+ if (driver->ops->install)
+ return driver->ops->install(driver, tty);
+
+ if (tty_init_termios(tty) == 0) {
+ tty_driver_kref_get(driver);
+ tty->count++;
+ driver->ttys[idx] = tty;
+ return 0;
+ }
+ return -ENOMEM;
+}
+
+/**
+ * tty_driver_remove_tty() - remove a tty from the driver tables
+ * @driver: the driver for the tty
+ * @idx: the minor number
+ *
+ * Remvoe a tty object from the driver tables. The tty->index field
+ * will be set by the time this is called.
+ *
+ * Locking: tty_mutex for now
+ */
+static void tty_driver_remove_tty(struct tty_driver *driver,
+ struct tty_struct *tty)
+{
+ if (driver->ops->remove)
+ driver->ops->remove(driver, tty);
+ else
+ driver->ttys[tty->index] = NULL;
+}
+
+/*
+ * tty_reopen() - fast re-open of an open tty
+ * @tty - the tty to open
+ *
+ * Return 0 on success, -errno on error.
+ *
+ * Locking: tty_mutex must be held from the time the tty was found
+ * till this open completes.
+ */
+static int tty_reopen(struct tty_struct *tty)
+{
+ struct tty_driver *driver = tty->driver;
+
+ if (test_bit(TTY_CLOSING, &tty->flags))
+ return -EIO;
+
+ if (driver->type == TTY_DRIVER_TYPE_PTY &&
+ driver->subtype == PTY_TYPE_MASTER) {
+ /*
+ * special case for PTY masters: only one open permitted,
+ * and the slave side open count is incremented as well.
+ */
+ if (tty->count)
+ return -EIO;
+
+ tty->link->count++;
+ }
+ tty->count++;
+ tty->driver = driver; /* N.B. why do this every time?? */
+
+ WARN_ON(!test_bit(TTY_LDISC, &tty->flags));
+
+ return 0;
+}
+
+/**
+ * tty_init_dev - initialise a tty device
* @driver: tty driver we are opening a device on
* @idx: device index
- * @tty: returned tty structure
+ * @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
* relaxed for the (most common) case of reopening a tty.
*/
-static int init_dev(struct tty_driver *driver, int idx,
- struct tty_struct **ret_tty)
+struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx,
+ int first_ok)
{
- struct tty_struct *tty, *o_tty;
- struct ktermios *tp, **tp_loc, *o_tp, **o_tp_loc;
- struct ktermios *ltp, **ltp_loc, *o_ltp, **o_ltp_loc;
- int retval = 0;
+ struct tty_struct *tty;
+ int retval;
- /* check whether we're reopening an existing tty */
- if (driver->flags & TTY_DRIVER_DEVPTS_MEM) {
- tty = devpts_get_tty(idx);
- /*
- * If we don't have a tty here on a slave open, it's because
- * the master already started the close process and there's
- * no relation between devpts file and tty anymore.
- */
- if (!tty && driver->subtype == PTY_TYPE_SLAVE) {
- retval = -EIO;
- goto end_init;
- }
- /*
- * It's safe from now on because init_dev() is called with
- * tty_mutex held and release_dev() won't change tty->count
- * or tty->flags without having to grab tty_mutex
- */
- if (tty && driver->subtype == PTY_TYPE_MASTER)
- tty = tty->link;
- } else {
- tty = driver->ttys[idx];
- }
- if (tty) goto fast_track;
+ /* 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.
* and locked termios may be retained.)
*/
- if (!try_module_get(driver->owner)) {
- retval = -ENODEV;
- goto end_init;
- }
-
- o_tty = NULL;
- tp = o_tp = NULL;
- ltp = o_ltp = NULL;
+ if (!try_module_get(driver->owner))
+ return ERR_PTR(-ENODEV);
tty = alloc_tty_struct();
if (!tty)
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);
-
- if (driver->flags & TTY_DRIVER_DEVPTS_MEM) {
- tp_loc = &tty->termios;
- ltp_loc = &tty->termios_locked;
- } else {
- tp_loc = &driver->termios[idx];
- ltp_loc = &driver->termios_locked[idx];
- }
-
- if (!*tp_loc) {
- tp = kmalloc(sizeof(struct ktermios), GFP_KERNEL);
- if (!tp)
- goto free_mem_out;
- *tp = driver->init_termios;
- }
+ initialize_tty_struct(tty, driver, idx);
- if (!*ltp_loc) {
- ltp = kzalloc(sizeof(struct ktermios), GFP_KERNEL);
- if (!ltp)
- goto free_mem_out;
- }
-
- if (driver->type == TTY_DRIVER_TYPE_PTY) {
- o_tty = alloc_tty_struct();
- if (!o_tty)
- 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);
-
- if (driver->flags & TTY_DRIVER_DEVPTS_MEM) {
- o_tp_loc = &o_tty->termios;
- o_ltp_loc = &o_tty->termios_locked;
- } else {
- o_tp_loc = &driver->other->termios[idx];
- o_ltp_loc = &driver->other->termios_locked[idx];
- }
-
- if (!*o_tp_loc) {
- o_tp = kmalloc(sizeof(struct ktermios), GFP_KERNEL);
- if (!o_tp)
- goto free_mem_out;
- *o_tp = driver->other->init_termios;
- }
-
- if (!*o_ltp_loc) {
- o_ltp = kzalloc(sizeof(struct ktermios), GFP_KERNEL);
- if (!o_ltp)
- goto free_mem_out;
- }
-
- /*
- * Everything allocated ... set up the o_tty structure.
- */
- if (!(driver->other->flags & TTY_DRIVER_DEVPTS_MEM))
- driver->other->ttys[idx] = o_tty;
- if (!*o_tp_loc)
- *o_tp_loc = o_tp;
- if (!*o_ltp_loc)
- *o_ltp_loc = o_ltp;
- o_tty->termios = *o_tp_loc;
- o_tty->termios_locked = *o_ltp_loc;
- driver->other->refcount++;
- if (driver->subtype == PTY_TYPE_MASTER)
- o_tty->count++;
-
- /* Establish the links in both directions */
- tty->link = o_tty;
- o_tty->link = tty;
+ retval = tty_driver_install_tty(driver, tty);
+ if (retval < 0) {
+ free_tty_struct(tty);
+ module_put(driver->owner);
+ return ERR_PTR(retval);
}
/*
- * All structures have been allocated, so now we install them.
- * Failures after this point use release_tty to clean up, so
- * there's no need to null out the local pointers.
- */
- if (!(driver->flags & TTY_DRIVER_DEVPTS_MEM))
- driver->ttys[idx] = tty;
-
- if (!*tp_loc)
- *tp_loc = tp;
- if (!*ltp_loc)
- *ltp_loc = ltp;
- tty->termios = *tp_loc;
- tty->termios_locked = *ltp_loc;
- /* 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);
- driver->refcount++;
- tty->count++;
-
- /*
* Structures all installed ... call the ldisc open routines.
* If we fail here just call release_tty to clean up. No need
* to decrement the use counts, as release_tty doesn't care.
*/
- retval = tty_ldisc_setup(tty, o_tty);
-
+ retval = tty_ldisc_setup(tty, tty->link);
if (retval)
goto release_mem_out;
- goto success;
-
- /*
- * This fast open can be used if the tty is already open.
- * No memory is allocated, and the only failures are from
- * attempting to open a closing tty or attempting multiple
- * opens on a pty master.
- */
-fast_track:
- if (test_bit(TTY_CLOSING, &tty->flags)) {
- retval = -EIO;
- goto end_init;
- }
- if (driver->type == TTY_DRIVER_TYPE_PTY &&
- driver->subtype == PTY_TYPE_MASTER) {
- /*
- * special case for PTY masters: only one open permitted,
- * and the slave side open count is incremented as well.
- */
- if (tty->count) {
- retval = -EIO;
- goto end_init;
- }
- tty->link->count++;
- }
- tty->count++;
- tty->driver = driver; /* N.B. why do this every time?? */
-
- /* FIXME */
- if (!test_bit(TTY_LDISC, &tty->flags))
- printk(KERN_ERR "init_dev but no ldisc\n");
-success:
- *ret_tty = tty;
-
- /* All paths come through here to release the mutex */
-end_init:
- return retval;
-
- /* Release locally allocated memory ... nothing placed in slots */
-free_mem_out:
- kfree(o_tp);
- if (o_tty)
- free_tty_struct(o_tty);
- kfree(ltp);
- kfree(tp);
- free_tty_struct(tty);
+ return tty;
fail_no_mem:
module_put(driver->owner);
- retval = -ENOMEM;
- goto end_init;
+ return ERR_PTR(-ENOMEM);
/* call the tty release_tty routine to clean out this slot */
release_mem_out:
if (printk_ratelimit())
- printk(KERN_INFO "init_dev: ldisc open failed, "
+ printk(KERN_INFO "tty_init_dev: ldisc open failed, "
"clearing slot %d\n", idx);
release_tty(tty, idx);
- goto end_init;
+ return ERR_PTR(retval);
}
+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);
+
+ tp = tty->termios_locked;
+ tty->driver->termios_locked[idx] = NULL;
+ kfree(tp);
+ }
+}
+EXPORT_SYMBOL(tty_free_termios);
+
+void tty_shutdown(struct tty_struct *tty)
+{
+ tty_driver_remove_tty(tty->driver, tty);
+ tty_free_termios(tty);
+}
+EXPORT_SYMBOL(tty_shutdown);
+
/**
* release_one_tty - release tty structure memory
* @kref: kref of tty we are obliterating
static void release_one_tty(struct kref *kref)
{
struct tty_struct *tty = container_of(kref, struct tty_struct, kref);
- int devpts = tty->driver->flags & TTY_DRIVER_DEVPTS_MEM;
- struct ktermios *tp;
- int idx = tty->index;
-
- if (!devpts)
- tty->driver->ttys[idx] = NULL;
-
- if (tty->driver->flags & TTY_DRIVER_RESET_TERMIOS) {
- /* FIXME: Locking on ->termios array */
- tp = tty->termios;
- if (!devpts)
- tty->driver->termios[idx] = NULL;
- kfree(tp);
-
- tp = tty->termios_locked;
- if (!devpts)
- tty->driver->termios_locked[idx] = NULL;
- kfree(tp);
- }
-
+ struct tty_driver *driver = tty->driver;
+ if (tty->ops->shutdown)
+ tty->ops->shutdown(tty);
+ else
+ tty_shutdown(tty);
tty->magic = 0;
- /* FIXME: locking on tty->driver->refcount */
- tty->driver->refcount--;
+ tty_driver_kref_put(driver);
+ module_put(driver->owner);
file_list_lock();
list_del_init(&tty->tty_files);
* of ttys that the driver keeps.
* FIXME: should we require tty_mutex is held here ??
*
- * FIXME: We want to defer the module put of the driver to the
- * destructor.
*/
static void release_tty(struct tty_struct *tty, int idx)
{
- struct tty_driver *driver = tty->driver;
-
/* This should always be true but check for the moment */
WARN_ON(tty->index != idx);
if (tty->link)
tty_kref_put(tty->link);
tty_kref_put(tty);
- module_put(driver->owner);
}
/*
* WSH 09/09/97: rewritten to avoid some nasty race conditions that could
* lead to double frees or releasing memory still in use.
*/
-static void release_dev(struct file *filp)
+void tty_release_dev(struct file *filp)
{
struct tty_struct *tty, *o_tty;
int pty_master, tty_closing, o_tty_closing, do_sleep;
int devpts;
int idx;
char buf[64];
+ struct inode *inode;
+ inode = filp->f_path.dentry->d_inode;
tty = (struct tty_struct *)filp->private_data;
- if (tty_paranoia_check(tty, filp->f_path.dentry->d_inode,
- "release_dev"))
+ if (tty_paranoia_check(tty, inode, "tty_release_dev"))
return;
- check_tty_count(tty, "release_dev");
+ check_tty_count(tty, "tty_release_dev");
tty_fasync(-1, filp, 0);
#ifdef TTY_PARANOIA_CHECK
if (idx < 0 || idx >= tty->driver->num) {
- printk(KERN_DEBUG "release_dev: bad idx when trying to "
+ printk(KERN_DEBUG "tty_release_dev: bad idx when trying to "
"free (%s)\n", tty->name);
return;
}
- if (!(tty->driver->flags & TTY_DRIVER_DEVPTS_MEM)) {
+ if (!devpts) {
if (tty != tty->driver->ttys[idx]) {
- printk(KERN_DEBUG "release_dev: driver.table[%d] not tty "
+ printk(KERN_DEBUG "tty_release_dev: driver.table[%d] not tty "
"for (%s)\n", idx, tty->name);
return;
}
if (tty->termios != tty->driver->termios[idx]) {
- printk(KERN_DEBUG "release_dev: driver.termios[%d] not termios "
+ printk(KERN_DEBUG "tty_release_dev: driver.termios[%d] not termios "
"for (%s)\n",
idx, tty->name);
return;
}
if (tty->termios_locked != tty->driver->termios_locked[idx]) {
- printk(KERN_DEBUG "release_dev: driver.termios_locked[%d] not "
+ printk(KERN_DEBUG "tty_release_dev: driver.termios_locked[%d] not "
"termios_locked for (%s)\n",
idx, tty->name);
return;
#endif
#ifdef TTY_DEBUG_HANGUP
- printk(KERN_DEBUG "release_dev of %s (tty count=%d)...",
+ printk(KERN_DEBUG "tty_release_dev of %s (tty count=%d)...",
tty_name(tty, buf), tty->count);
#endif
if (tty->driver->other &&
!(tty->driver->flags & TTY_DRIVER_DEVPTS_MEM)) {
if (o_tty != tty->driver->other->ttys[idx]) {
- printk(KERN_DEBUG "release_dev: other->table[%d] "
+ printk(KERN_DEBUG "tty_release_dev: other->table[%d] "
"not o_tty for (%s)\n",
idx, tty->name);
return;
}
if (o_tty->termios != tty->driver->other->termios[idx]) {
- printk(KERN_DEBUG "release_dev: other->termios[%d] "
+ printk(KERN_DEBUG "tty_release_dev: other->termios[%d] "
"not o_termios for (%s)\n",
idx, tty->name);
return;
}
if (o_tty->termios_locked !=
tty->driver->other->termios_locked[idx]) {
- printk(KERN_DEBUG "release_dev: other->termios_locked["
+ printk(KERN_DEBUG "tty_release_dev: other->termios_locked["
"%d] not o_termios_locked for (%s)\n",
idx, tty->name);
return;
}
if (o_tty->link != tty) {
- printk(KERN_DEBUG "release_dev: bad pty pointers\n");
+ printk(KERN_DEBUG "tty_release_dev: bad pty pointers\n");
return;
}
}
if (!do_sleep)
break;
- printk(KERN_WARNING "release_dev: %s: read/write wait queue "
+ printk(KERN_WARNING "tty_release_dev: %s: read/write wait queue "
"active!\n", tty_name(tty, buf));
mutex_unlock(&tty_mutex);
schedule();
*/
if (pty_master) {
if (--o_tty->count < 0) {
- printk(KERN_WARNING "release_dev: bad pty slave count "
+ printk(KERN_WARNING "tty_release_dev: bad pty slave count "
"(%d) for %s\n",
o_tty->count, tty_name(o_tty, buf));
o_tty->count = 0;
}
}
if (--tty->count < 0) {
- printk(KERN_WARNING "release_dev: bad tty->count (%d) for %s\n",
+ printk(KERN_WARNING "tty_release_dev: bad tty->count (%d) for %s\n",
tty->count, tty_name(tty, buf));
tty->count = 0;
}
/* Make this pty number available for reallocation */
if (devpts)
- devpts_kill_index(idx);
+ devpts_kill_index(inode, idx);
}
/**
- * tty_open - open a tty device
+ * __tty_open - open a tty device
* @inode: inode of device file
* @filp: file pointer to tty
*
* 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 init_dev work.
+ * Locking: tty_mutex protects tty, get_tty_driver and tty_init_dev work.
* tty->count should protect the rest.
* ->siglock protects ->signal/->sighand
*/
static int __tty_open(struct inode *inode, struct file *filp)
{
- struct tty_struct *tty;
+ struct tty_struct *tty = NULL;
int noctty, retval;
struct tty_driver *driver;
int index;
mutex_unlock(&tty_mutex);
return -ENXIO;
}
- driver = tty->driver;
+ 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 = console_driver;
+ driver = tty_driver_kref_get(console_driver);
index = fg_console;
noctty = 1;
goto got_driver;
}
#endif
if (device == MKDEV(TTYAUX_MAJOR, 1)) {
- driver = console_device(&index);
+ driver = tty_driver_kref_get(console_device(&index));
if (driver) {
/* Don't let /dev/console block */
filp->f_flags |= O_NONBLOCK;
return -ENODEV;
}
got_driver:
- retval = init_dev(driver, index, &tty);
+ if (!tty) {
+ /* check whether we're reopening an existing tty */
+ tty = tty_driver_lookup_tty(driver, inode, index);
+
+ if (IS_ERR(tty))
+ return PTR_ERR(tty);
+ }
+
+ if (tty) {
+ retval = tty_reopen(tty);
+ if (retval)
+ tty = ERR_PTR(retval);
+ } else
+ tty = tty_init_dev(driver, index, 0);
+
mutex_unlock(&tty_mutex);
- if (retval)
- return retval;
+ tty_driver_kref_put(driver);
+ if (IS_ERR(tty))
+ return PTR_ERR(tty);
filp->private_data = tty;
file_move(filp, &tty->tty_files);
printk(KERN_DEBUG "error %d in opening %s...", retval,
tty->name);
#endif
- release_dev(filp);
+ tty_release_dev(filp);
if (retval != -ERESTARTSYS)
return retval;
if (signal_pending(current))
-#ifdef CONFIG_UNIX98_PTYS
-/**
- * ptmx_open - open a unix 98 pty master
- * @inode: inode of device file
- * @filp: file pointer to tty
- *
- * Allocate a unix98 pty master device from the ptmx driver.
- *
- * Locking: tty_mutex protects theinit_dev work. tty->count should
- * protect the rest.
- * allocated_ptys_lock handles the list of free pty numbers
- */
-
-static int __ptmx_open(struct inode *inode, struct file *filp)
-{
- struct tty_struct *tty;
- int retval;
- int index;
-
- nonseekable_open(inode, filp);
-
- /* find a device that is not in use. */
- index = devpts_new_index();
- if (index < 0)
- return index;
-
- mutex_lock(&tty_mutex);
- retval = init_dev(ptm_driver, index, &tty);
- mutex_unlock(&tty_mutex);
-
- if (retval)
- goto out;
-
- set_bit(TTY_PTY_LOCK, &tty->flags); /* LOCK THE SLAVE */
- filp->private_data = tty;
- file_move(filp, &tty->tty_files);
-
- retval = devpts_pty_new(tty->link);
- if (retval)
- goto out1;
-
- check_tty_count(tty, "ptmx_open");
- retval = ptm_driver->ops->open(tty, filp);
- if (!retval)
- return 0;
-out1:
- release_dev(filp);
- return retval;
-out:
- devpts_kill_index(index);
- return retval;
-}
-
-static int ptmx_open(struct inode *inode, struct file *filp)
-{
- int ret;
-
- lock_kernel();
- ret = __ptmx_open(inode, filp);
- unlock_kernel();
- return ret;
-}
-#endif
/**
* tty_release - vfs callback for close
* this tty. There may however be several such references.
*
* Locking:
- * Takes bkl. See release_dev
+ * Takes bkl. See tty_release_dev
*/
static int tty_release(struct inode *inode, struct file *filp)
{
lock_kernel();
- release_dev(filp);
+ tty_release_dev(filp);
unlock_kernel();
return 0;
}
/* For a PTY we need to lock the tty side */
mutex_lock(&real_tty->termios_mutex);
- if (!memcmp(ws, &tty->winsize, sizeof(*ws)))
+ if (!memcmp(ws, &real_tty->winsize, sizeof(*ws)))
goto done;
/* Get the PID values and reference them so we can
avoid holding the tty ctrl lock while sending signals */
case TIOCSTI:
return tiocsti(tty, p);
case TIOCGWINSZ:
- return tiocgwinsz(tty, p);
+ return tiocgwinsz(real_tty, p);
case TIOCSWINSZ:
return tiocswinsz(tty, real_tty, p);
case TIOCCONS:
* Locking: none - tty in question must not be exposed at this point
*/
-static void initialize_tty_struct(struct tty_struct *tty)
+void initialize_tty_struct(struct tty_struct *tty,
+ struct tty_driver *driver, int idx)
{
memset(tty, 0, sizeof(struct tty_struct));
kref_init(&tty->kref);
spin_lock_init(&tty->ctrl_lock);
INIT_LIST_HEAD(&tty->tty_files);
INIT_WORK(&tty->SAK_work, do_SAK_work);
+
+ tty->driver = driver;
+ tty->ops = driver->ops;
+ tty->index = idx;
+ tty_line_name(driver, idx, tty->name);
}
/**
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;
+struct class *tty_class;
/**
* tty_register_device - register a tty device
return device_create_drvdata(tty_class, device, dev, NULL, name);
}
+EXPORT_SYMBOL(tty_register_device);
/**
* tty_unregister_device - unregister a tty device
device_destroy(tty_class,
MKDEV(driver->major, driver->minor_start) + index);
}
-
-EXPORT_SYMBOL(tty_register_device);
EXPORT_SYMBOL(tty_unregister_device);
struct tty_driver *alloc_tty_driver(int lines)
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 */
}
return driver;
}
+EXPORT_SYMBOL(alloc_tty_driver);
-void put_tty_driver(struct tty_driver *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) {
+ /*
+ * Free the termios and termios_locked structures because
+ * we don't want to get memory leaks when modular tty
+ * drivers are removed from the kernel.
+ */
+ for (i = 0; i < driver->num; i++) {
+ tp = driver->termios[i];
+ if (tp) {
+ driver->termios[i] = NULL;
+ kfree(tp);
+ }
+ tp = driver->termios_locked[i];
+ if (tp) {
+ driver->termios_locked[i] = NULL;
+ kfree(tp);
+ }
+ 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 = driver->termios_locked = NULL;
+ kfree(p);
+ cdev_del(&driver->cdev);
+ }
kfree(driver);
}
+void tty_driver_kref_put(struct tty_driver *driver)
+{
+ kref_put(&driver->kref, destruct_tty_driver);
+}
+EXPORT_SYMBOL(tty_driver_kref_put);
+
void tty_set_operations(struct tty_driver *driver,
const struct tty_operations *op)
{
driver->ops = op;
};
+EXPORT_SYMBOL(tty_set_operations);
-EXPORT_SYMBOL(alloc_tty_driver);
+void put_tty_driver(struct tty_driver *d)
+{
+ tty_driver_kref_put(d);
+}
EXPORT_SYMBOL(put_tty_driver);
-EXPORT_SYMBOL(tty_set_operations);
/*
* Called by a tty driver to register itself.
dev_t dev;
void **p = NULL;
- if (driver->flags & TTY_DRIVER_INSTALLED)
- return 0;
-
if (!(driver->flags & TTY_DRIVER_DEVPTS_MEM) && driver->num) {
p = kzalloc(driver->num * 3 * sizeof(void *), GFP_KERNEL);
if (!p)
tty_register_device(driver, i, NULL);
}
proc_tty_register_driver(driver);
+ driver->flags |= TTY_DRIVER_INSTALLED;
return 0;
}
*/
int tty_unregister_driver(struct tty_driver *driver)
{
- int i;
- struct ktermios *tp;
- void *p;
-
+#if 0
+ /* FIXME */
if (driver->refcount)
return -EBUSY;
-
+#endif
unregister_chrdev_region(MKDEV(driver->major, driver->minor_start),
driver->num);
mutex_lock(&tty_mutex);
list_del(&driver->tty_drivers);
mutex_unlock(&tty_mutex);
-
- /*
- * Free the termios and termios_locked structures because
- * we don't want to get memory leaks when modular tty
- * drivers are removed from the kernel.
- */
- for (i = 0; i < driver->num; i++) {
- tp = driver->termios[i];
- if (tp) {
- driver->termios[i] = NULL;
- kfree(tp);
- }
- tp = driver->termios_locked[i];
- if (tp) {
- driver->termios_locked[i] = NULL;
- kfree(tp);
- }
- 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 = driver->termios_locked = NULL;
- kfree(p);
- cdev_del(&driver->cdev);
return 0;
}
+
EXPORT_SYMBOL(tty_unregister_driver);
dev_t tty_devnum(struct tty_struct *tty)
struct tty_struct *get_current_tty(void)
{
struct tty_struct *tty;
- WARN_ON_ONCE(!mutex_is_locked(&tty_mutex));
- tty = current->signal->tty;
- /*
- * session->tty can be changed/cleared from under us, make sure we
- * issue the load. The obtained pointer, when not NULL, is valid as
- * long as we hold tty_mutex.
- */
- barrier();
+ unsigned long flags;
+
+ spin_lock_irqsave(¤t->sighand->siglock, flags);
+ tty = tty_kref_get(current->signal->tty);
+ spin_unlock_irqrestore(¤t->sighand->siglock, flags);
return tty;
}
EXPORT_SYMBOL_GPL(get_current_tty);
+void tty_default_fops(struct file_operations *fops)
+{
+ *fops = tty_fops;
+}
+
/*
* Initialize the console device. This is called *early*, so
* we can't necessarily depend on lots of kernel help here.
/* 3/2004 jmc: why do these devices exist? */
static struct cdev tty_cdev, console_cdev;
-#ifdef CONFIG_UNIX98_PTYS
-static struct cdev ptmx_cdev;
-#endif
-#ifdef CONFIG_VT
-static struct cdev vc0_cdev;
-#endif
/*
* Ok, now we can initialize the rest of the tty devices and can count
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_drvdata(tty_class, NULL, MKDEV(TTYAUX_MAJOR, 0), NULL,
+ 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_drvdata(tty_class, NULL, MKDEV(TTYAUX_MAJOR, 1), NULL,
+ device_create(tty_class, NULL, MKDEV(TTYAUX_MAJOR, 1), NULL,
"console");
-#ifdef CONFIG_UNIX98_PTYS
- cdev_init(&ptmx_cdev, &ptmx_fops);
- if (cdev_add(&ptmx_cdev, MKDEV(TTYAUX_MAJOR, 2), 1) ||
- register_chrdev_region(MKDEV(TTYAUX_MAJOR, 2), 1, "/dev/ptmx") < 0)
- panic("Couldn't register /dev/ptmx driver\n");
- device_create_drvdata(tty_class, NULL, MKDEV(TTYAUX_MAJOR, 2), NULL, "ptmx");
-#endif
-
#ifdef CONFIG_VT
- cdev_init(&vc0_cdev, &console_fops);
- if (cdev_add(&vc0_cdev, MKDEV(TTY_MAJOR, 0), 1) ||
- register_chrdev_region(MKDEV(TTY_MAJOR, 0), 1, "/dev/vc/0") < 0)
- panic("Couldn't register /dev/tty0 driver\n");
- device_create_drvdata(tty_class, NULL, MKDEV(TTY_MAJOR, 0), NULL, "tty0");
-
- vty_init();
+ vty_init(&console_fops);
#endif
return 0;
}
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff