diff options
Diffstat (limited to 'drivers/tty/pty.c')
| -rw-r--r-- | drivers/tty/pty.c | 227 |
1 files changed, 89 insertions, 138 deletions
diff --git a/drivers/tty/pty.c b/drivers/tty/pty.c index 00099a8439d2..6120d827a797 100644 --- a/drivers/tty/pty.c +++ b/drivers/tty/pty.c @@ -29,6 +29,7 @@ #include <linux/file.h> #include <linux/ioctl.h> #include <linux/compat.h> +#include "tty.h" #undef TTY_DEBUG_HANGUP #ifdef TTY_DEBUG_HANGUP @@ -45,7 +46,6 @@ static DEFINE_MUTEX(devpts_mutex); static void pty_close(struct tty_struct *tty, struct file *filp) { - BUG_ON(!tty); if (tty->driver->subtype == PTY_TYPE_MASTER) WARN_ON(tty->count > 1); else { @@ -57,9 +57,8 @@ static void pty_close(struct tty_struct *tty, struct file *filp) set_bit(TTY_IO_ERROR, &tty->flags); wake_up_interruptible(&tty->read_wait); wake_up_interruptible(&tty->write_wait); - spin_lock_irq(&tty->ctrl_lock); - tty->packet = 0; - spin_unlock_irq(&tty->ctrl_lock); + scoped_guard(spinlock_irq, &tty->ctrl.lock) + tty->ctrl.packet = false; /* Review - krefs on tty_link ?? */ if (!tty->link) return; @@ -70,10 +69,9 @@ static void pty_close(struct tty_struct *tty, struct file *filp) set_bit(TTY_OTHER_CLOSED, &tty->flags); #ifdef CONFIG_UNIX98_PTYS if (tty->driver == ptm_driver) { - mutex_lock(&devpts_mutex); + guard(mutex)(&devpts_mutex); if (tty->link->driver_data) devpts_pty_kill(tty->link->driver_data); - mutex_unlock(&devpts_mutex); } #endif tty_vhangup(tty->link); @@ -100,7 +98,7 @@ static void pty_unthrottle(struct tty_struct *tty) * pty_write - write to a pty * @tty: the tty we write from * @buf: kernel buffer of data - * @count: bytes to write + * @c: bytes to write * * Our "hardware" write method. Data is coming from the ldisc which * may be in a non sleeping state. We simply throw this at the other @@ -108,24 +106,14 @@ static void pty_unthrottle(struct tty_struct *tty) * the other side of the pty/tty pair. */ -static int pty_write(struct tty_struct *tty, const unsigned char *buf, int c) +static ssize_t pty_write(struct tty_struct *tty, const u8 *buf, size_t c) { struct tty_struct *to = tty->link; - unsigned long flags; - if (tty->stopped) + if (tty->flow.stopped || !c) return 0; - if (c > 0) { - spin_lock_irqsave(&to->port->lock, flags); - /* Stuff the data into the input queue of the other end */ - c = tty_insert_flip_string(to->port, buf, c); - /* And shovel */ - if (c) - tty_flip_buffer_push(to->port); - spin_unlock_irqrestore(&to->port->lock, flags); - } - return c; + return tty_insert_flip_string_and_push_buffer(to->port, buf, c); } /** @@ -136,30 +124,18 @@ static int pty_write(struct tty_struct *tty, const unsigned char *buf, int c) * the other device. */ -static int pty_write_room(struct tty_struct *tty) +static unsigned int pty_write_room(struct tty_struct *tty) { - if (tty->stopped) + if (tty->flow.stopped) return 0; return tty_buffer_space_avail(tty->link->port); } -/** - * pty_chars_in_buffer - characters currently in our tx queue - * @tty: our tty - * - * Report how much we have in the transmit queue. As everything is - * instantly at the other end this is easy to implement. - */ - -static int pty_chars_in_buffer(struct tty_struct *tty) -{ - return 0; -} - /* Set the lock flag on a pty */ static int pty_set_lock(struct tty_struct *tty, int __user *arg) { int val; + if (get_user(val, arg)) return -EFAULT; if (val) @@ -172,27 +148,30 @@ static int pty_set_lock(struct tty_struct *tty, int __user *arg) static int pty_get_lock(struct tty_struct *tty, int __user *arg) { int locked = test_bit(TTY_PTY_LOCK, &tty->flags); + return put_user(locked, arg); } /* Set the packet mode on a pty */ static int pty_set_pktmode(struct tty_struct *tty, int __user *arg) { - int pktmode; + int want_pktmode; - if (get_user(pktmode, arg)) + if (get_user(want_pktmode, arg)) return -EFAULT; - spin_lock_irq(&tty->ctrl_lock); - if (pktmode) { - if (!tty->packet) { - tty->link->ctrl_status = 0; - smp_mb(); - tty->packet = 1; - } - } else - tty->packet = 0; - spin_unlock_irq(&tty->ctrl_lock); + guard(spinlock_irq)(&tty->ctrl.lock); + if (!want_pktmode) { + tty->ctrl.packet = false; + return 0; + } + + if (tty->ctrl.packet) + return 0; + + tty->link->ctrl.pktstatus = 0; + smp_mb(); + tty->ctrl.packet = true; return 0; } @@ -200,7 +179,8 @@ static int pty_set_pktmode(struct tty_struct *tty, int __user *arg) /* Get the packet mode of a pty */ static int pty_get_pktmode(struct tty_struct *tty, int __user *arg) { - int pktmode = tty->packet; + int pktmode = tty->ctrl.packet; + return put_user(pktmode, arg); } @@ -229,11 +209,10 @@ static void pty_flush_buffer(struct tty_struct *tty) return; tty_buffer_flush(to, NULL); - if (to->packet) { - spin_lock_irq(&tty->ctrl_lock); - tty->ctrl_status |= TIOCPKT_FLUSHWRITE; + if (to->ctrl.packet) { + guard(spinlock_irq)(&tty->ctrl.lock); + tty->ctrl.pktstatus |= TIOCPKT_FLUSHWRITE; wake_up_interruptible(&to->read_wait); - spin_unlock_irq(&tty->ctrl_lock); } } @@ -260,10 +239,10 @@ out: } static void pty_set_termios(struct tty_struct *tty, - struct ktermios *old_termios) + const struct ktermios *old_termios) { /* See if packet mode change of state. */ - if (tty->link && tty->link->packet) { + if (tty->link && tty->link->ctrl.packet) { int extproc = (old_termios->c_lflag & EXTPROC) | L_EXTPROC(tty); int old_flow = ((old_termios->c_iflag & IXON) && (old_termios->c_cc[VSTOP] == '\023') && @@ -272,17 +251,17 @@ static void pty_set_termios(struct tty_struct *tty, STOP_CHAR(tty) == '\023' && START_CHAR(tty) == '\021'); if ((old_flow != new_flow) || extproc) { - spin_lock_irq(&tty->ctrl_lock); - if (old_flow != new_flow) { - tty->ctrl_status &= ~(TIOCPKT_DOSTOP | TIOCPKT_NOSTOP); - if (new_flow) - tty->ctrl_status |= TIOCPKT_DOSTOP; - else - tty->ctrl_status |= TIOCPKT_NOSTOP; + scoped_guard(spinlock_irq, &tty->ctrl.lock) { + if (old_flow != new_flow) { + tty->ctrl.pktstatus &= ~(TIOCPKT_DOSTOP | TIOCPKT_NOSTOP); + if (new_flow) + tty->ctrl.pktstatus |= TIOCPKT_DOSTOP; + else + tty->ctrl.pktstatus |= TIOCPKT_NOSTOP; + } + if (extproc) + tty->ctrl.pktstatus |= TIOCPKT_IOCTL; } - if (extproc) - tty->ctrl_status |= TIOCPKT_IOCTL; - spin_unlock_irq(&tty->ctrl_lock); wake_up_interruptible(&tty->link->read_wait); } } @@ -292,7 +271,7 @@ static void pty_set_termios(struct tty_struct *tty, } /** - * pty_do_resize - resize event + * pty_resize - resize event * @tty: tty being resized * @ws: window size being set. * @@ -306,9 +285,9 @@ static int pty_resize(struct tty_struct *tty, struct winsize *ws) struct tty_struct *pty = tty->link; /* For a PTY we need to lock the tty side */ - mutex_lock(&tty->winsize_mutex); + guard(mutex)(&tty->winsize_mutex); if (!memcmp(ws, &tty->winsize, sizeof(*ws))) - goto done; + return 0; /* Signal the foreground process group of both ptys */ pgrp = tty_get_pgrp(tty); @@ -324,8 +303,7 @@ static int pty_resize(struct tty_struct *tty, struct winsize *ws) tty->winsize = *ws; pty->winsize = *ws; /* Never used so will go away soon */ -done: - mutex_unlock(&tty->winsize_mutex); + return 0; } @@ -341,28 +319,26 @@ done: */ static void pty_start(struct tty_struct *tty) { - unsigned long flags; + if (!tty->link || !tty->link->ctrl.packet) + return; - if (tty->link && tty->link->packet) { - spin_lock_irqsave(&tty->ctrl_lock, flags); - tty->ctrl_status &= ~TIOCPKT_STOP; - tty->ctrl_status |= TIOCPKT_START; - spin_unlock_irqrestore(&tty->ctrl_lock, flags); - wake_up_interruptible_poll(&tty->link->read_wait, EPOLLIN); + scoped_guard(spinlock_irqsave, &tty->ctrl.lock) { + tty->ctrl.pktstatus &= ~TIOCPKT_STOP; + tty->ctrl.pktstatus |= TIOCPKT_START; } + wake_up_interruptible_poll(&tty->link->read_wait, EPOLLIN); } static void pty_stop(struct tty_struct *tty) { - unsigned long flags; + if (!tty->link || !tty->link->ctrl.packet) + return; - if (tty->link && tty->link->packet) { - spin_lock_irqsave(&tty->ctrl_lock, flags); - tty->ctrl_status &= ~TIOCPKT_START; - tty->ctrl_status |= TIOCPKT_STOP; - spin_unlock_irqrestore(&tty->ctrl_lock, flags); - wake_up_interruptible_poll(&tty->link->read_wait, EPOLLIN); + scoped_guard(spinlock_irqsave, &tty->ctrl.lock) { + tty->ctrl.pktstatus &= ~TIOCPKT_START; + tty->ctrl.pktstatus |= TIOCPKT_STOP; } + wake_up_interruptible_poll(&tty->link->read_wait, EPOLLIN); } /** @@ -464,6 +440,7 @@ static int pty_install(struct tty_driver *driver, struct tty_struct *tty) static void pty_remove(struct tty_driver *driver, struct tty_struct *tty) { struct tty_struct *pair = tty->link; + driver->ttys[tty->index] = NULL; if (pair) pair->driver->ttys[pair->index] = NULL; @@ -521,7 +498,6 @@ static const struct tty_operations master_pty_ops_bsd = { .write = pty_write, .write_room = pty_write_room, .flush_buffer = pty_flush_buffer, - .chars_in_buffer = pty_chars_in_buffer, .unthrottle = pty_unthrottle, .ioctl = pty_bsd_ioctl, .compat_ioctl = pty_bsd_compat_ioctl, @@ -537,7 +513,6 @@ static const struct tty_operations slave_pty_ops_bsd = { .write = pty_write, .write_room = pty_write_room, .flush_buffer = pty_flush_buffer, - .chars_in_buffer = pty_chars_in_buffer, .unthrottle = pty_unthrottle, .set_termios = pty_set_termios, .cleanup = pty_cleanup, @@ -610,6 +585,23 @@ static inline void legacy_pty_init(void) { } #ifdef CONFIG_UNIX98_PTYS static struct cdev ptmx_cdev; +static struct file *ptm_open_peer_file(struct file *master, + struct tty_struct *tty, int flags) +{ + struct path path; + struct file *file; + + /* Compute the slave's path */ + path.mnt = devpts_mntget(master, tty->driver_data); + if (IS_ERR(path.mnt)) + return ERR_CAST(path.mnt); + path.dentry = tty->link->driver_data; + + file = dentry_open(&path, flags, current_cred()); + mntput(path.mnt); + return file; +} + /** * ptm_open_peer - open the peer of a pty * @master: the open struct file of the ptmx device node @@ -622,42 +614,10 @@ static struct cdev ptmx_cdev; */ int ptm_open_peer(struct file *master, struct tty_struct *tty, int flags) { - int fd = -1; - struct file *filp; - int retval = -EINVAL; - struct path path; - if (tty->driver != ptm_driver) return -EIO; - fd = get_unused_fd_flags(flags); - if (fd < 0) { - retval = fd; - goto err; - } - - /* Compute the slave's path */ - path.mnt = devpts_mntget(master, tty->driver_data); - if (IS_ERR(path.mnt)) { - retval = PTR_ERR(path.mnt); - goto err_put; - } - path.dentry = tty->link->driver_data; - - filp = dentry_open(&path, flags, current_cred()); - mntput(path.mnt); - if (IS_ERR(filp)) { - retval = PTR_ERR(filp); - goto err_put; - } - - fd_install(fd, filp); - return fd; - -err_put: - put_unused_fd(fd); -err: - return retval; + return FD_ADD(flags, ptm_open_peer_file(master, tty, flags)); } static int pty_unix98_ioctl(struct tty_struct *tty, @@ -699,6 +659,7 @@ static long pty_unix98_compat_ioctl(struct tty_struct *tty, /** * ptm_unix98_lookup - find a pty master * @driver: ptm driver + * @file: unused * @idx: tty index * * Look up a pty master device. Called under the tty_mutex for now. @@ -715,6 +676,7 @@ static struct tty_struct *ptm_unix98_lookup(struct tty_driver *driver, /** * pts_unix98_lookup - find a pty slave * @driver: pts driver + * @file: file pointer to tty * @idx: tty index * * Look up a pty master device. Called under the tty_mutex for now. @@ -724,15 +686,9 @@ static struct tty_struct *ptm_unix98_lookup(struct tty_driver *driver, static struct tty_struct *pts_unix98_lookup(struct tty_driver *driver, struct file *file, int idx) { - struct tty_struct *tty; - - mutex_lock(&devpts_mutex); - tty = devpts_get_priv(file->f_path.dentry); - mutex_unlock(&devpts_mutex); + guard(mutex)(&devpts_mutex); /* Master must be open before slave */ - if (!tty) - return ERR_PTR(-EIO); - return tty; + return devpts_get_priv(file->f_path.dentry) ? : ERR_PTR(-EIO); } static int pty_unix98_install(struct tty_driver *driver, struct tty_struct *tty) @@ -770,7 +726,6 @@ static const struct tty_operations ptm_unix98_ops = { .write = pty_write, .write_room = pty_write_room, .flush_buffer = pty_flush_buffer, - .chars_in_buffer = pty_chars_in_buffer, .unthrottle = pty_unthrottle, .ioctl = pty_unix98_ioctl, .compat_ioctl = pty_unix98_compat_ioctl, @@ -788,7 +743,6 @@ static const struct tty_operations pty_unix98_ops = { .write = pty_write, .write_room = pty_write_room, .flush_buffer = pty_flush_buffer, - .chars_in_buffer = pty_chars_in_buffer, .unthrottle = pty_unthrottle, .set_termios = pty_set_termios, .start = pty_start, @@ -819,7 +773,7 @@ static int ptmx_open(struct inode *inode, struct file *filp) nonseekable_open(inode, filp); /* We refuse fsnotify events on ptmx, since it's a shared resource */ - filp->f_mode |= FMODE_NONOTIFY; + file_set_fsnotify_mode(filp, FMODE_NONOTIFY); retval = tty_alloc_file(filp); if (retval) @@ -832,20 +786,17 @@ static int ptmx_open(struct inode *inode, struct file *filp) } /* find a device that is not in use. */ - mutex_lock(&devpts_mutex); - index = devpts_new_index(fsi); - mutex_unlock(&devpts_mutex); + scoped_guard(mutex, &devpts_mutex) + index = devpts_new_index(fsi); retval = index; if (index < 0) goto out_put_fsi; - mutex_lock(&tty_mutex); - tty = tty_init_dev(ptm_driver, index); - /* The tty returned here is locked so we can safely - drop the mutex */ - mutex_unlock(&tty_mutex); + /* The tty returned here is locked so we can safely drop the mutex */ + scoped_guard(mutex, &tty_mutex) + tty = tty_init_dev(ptm_driver, index); retval = PTR_ERR(tty); if (IS_ERR(tty)) @@ -952,7 +903,7 @@ static void __init unix98_pty_init(void) 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"); - device_create(tty_class, NULL, MKDEV(TTYAUX_MAJOR, 2), NULL, "ptmx"); + device_create(&tty_class, NULL, MKDEV(TTYAUX_MAJOR, 2), NULL, "ptmx"); } #else |