diff options
Diffstat (limited to 'drivers/char/tty_io.c')
| -rw-r--r-- | drivers/char/tty_io.c | 378 |
1 files changed, 210 insertions, 168 deletions
diff --git a/drivers/char/tty_io.c b/drivers/char/tty_io.c index 98b65a230994..49c1a2267a55 100644 --- a/drivers/char/tty_io.c +++ b/drivers/char/tty_io.c @@ -78,6 +78,7 @@ #include <linux/tty_flip.h> #include <linux/devpts_fs.h> #include <linux/file.h> +#include <linux/fdtable.h> #include <linux/console.h> #include <linux/timer.h> #include <linux/ctype.h> @@ -91,7 +92,6 @@ #include <linux/module.h> #include <linux/smp_lock.h> #include <linux/device.h> -#include <linux/idr.h> #include <linux/wait.h> #include <linux/bitops.h> #include <linux/delay.h> @@ -137,9 +137,6 @@ EXPORT_SYMBOL(tty_mutex); #ifdef CONFIG_UNIX98_PTYS extern struct tty_driver *ptm_driver; /* Unix98 pty masters; for /dev/ptmx */ -extern int pty_limit; /* Config limit on Unix98 ptys */ -static DEFINE_IDR(allocated_ptys); -static DEFINE_MUTEX(allocated_ptys_lock); static int ptmx_open(struct inode *, struct file *); #endif @@ -152,8 +149,7 @@ ssize_t redirected_tty_write(struct file *, const char __user *, static unsigned int tty_poll(struct file *, poll_table *); static int tty_open(struct inode *, struct file *); static int tty_release(struct inode *, struct file *); -int tty_ioctl(struct inode *inode, struct file *file, - unsigned int cmd, unsigned long arg); +long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg); #ifdef CONFIG_COMPAT static long tty_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg); @@ -1109,8 +1105,8 @@ restart: a reference to the old ldisc. If we ended up flipping back to the existing ldisc we have two references to it */ - if (tty->ldisc.num != o_ldisc.num && tty->driver->set_ldisc) - tty->driver->set_ldisc(tty); + if (tty->ldisc.num != o_ldisc.num && tty->ops->set_ldisc) + tty->ops->set_ldisc(tty); tty_ldisc_put(o_ldisc.num); @@ -1182,9 +1178,8 @@ struct tty_driver *tty_find_polling_driver(char *name, int *line) if (*str == '\0') str = NULL; - if (tty_line >= 0 && tty_line <= p->num && p->poll_init && - !p->poll_init(p, tty_line, str)) { - + if (tty_line >= 0 && tty_line <= p->num && p->ops && + p->ops->poll_init && !p->ops->poll_init(p, tty_line, str)) { res = p; *line = tty_line; break; @@ -1205,26 +1200,37 @@ EXPORT_SYMBOL_GPL(tty_find_polling_driver); * not in the foreground, send a SIGTTOU. If the signal is blocked or * ignored, go ahead and perform the operation. (POSIX 7.2) * - * Locking: none + * Locking: ctrl_lock */ int tty_check_change(struct tty_struct *tty) { + unsigned long flags; + int ret = 0; + if (current->signal->tty != tty) return 0; + + spin_lock_irqsave(&tty->ctrl_lock, flags); + if (!tty->pgrp) { printk(KERN_WARNING "tty_check_change: tty->pgrp == NULL!\n"); - return 0; + goto out; } if (task_pgrp(current) == tty->pgrp) - return 0; + goto out; if (is_ignored(SIGTTOU)) - return 0; - if (is_current_pgrp_orphaned()) - return -EIO; + goto out; + if (is_current_pgrp_orphaned()) { + ret = -EIO; + goto out; + } kill_pgrp(task_pgrp(current), SIGTTOU, 1); set_thread_flag(TIF_SIGPENDING); - return -ERESTARTSYS; + ret = -ERESTARTSYS; +out: + spin_unlock_irqrestore(&tty->ctrl_lock, flags); + return ret; } EXPORT_SYMBOL(tty_check_change); @@ -1247,8 +1253,8 @@ static unsigned int hung_up_tty_poll(struct file *filp, poll_table *wait) return POLLIN | POLLOUT | POLLERR | POLLHUP | POLLRDNORM | POLLWRNORM; } -static int hung_up_tty_ioctl(struct inode *inode, struct file *file, - unsigned int cmd, unsigned long arg) +static long hung_up_tty_ioctl(struct file *file, unsigned int cmd, + unsigned long arg) { return cmd == TIOCSPGRP ? -ENOTTY : -EIO; } @@ -1264,7 +1270,7 @@ static const struct file_operations tty_fops = { .read = tty_read, .write = tty_write, .poll = tty_poll, - .ioctl = tty_ioctl, + .unlocked_ioctl = tty_ioctl, .compat_ioctl = tty_compat_ioctl, .open = tty_open, .release = tty_release, @@ -1277,7 +1283,7 @@ static const struct file_operations ptmx_fops = { .read = tty_read, .write = tty_write, .poll = tty_poll, - .ioctl = tty_ioctl, + .unlocked_ioctl = tty_ioctl, .compat_ioctl = tty_compat_ioctl, .open = ptmx_open, .release = tty_release, @@ -1290,7 +1296,7 @@ static const struct file_operations console_fops = { .read = tty_read, .write = redirected_tty_write, .poll = tty_poll, - .ioctl = tty_ioctl, + .unlocked_ioctl = tty_ioctl, .compat_ioctl = tty_compat_ioctl, .open = tty_open, .release = tty_release, @@ -1302,7 +1308,7 @@ static const struct file_operations hung_up_tty_fops = { .read = hung_up_tty_read, .write = hung_up_tty_write, .poll = hung_up_tty_poll, - .ioctl = hung_up_tty_ioctl, + .unlocked_ioctl = hung_up_tty_ioctl, .compat_ioctl = hung_up_tty_compat_ioctl, .release = tty_release, }; @@ -1404,6 +1410,7 @@ static void do_tty_hangup(struct work_struct *work) struct task_struct *p; struct tty_ldisc *ld; int closecount = 0, n; + unsigned long flags; if (!tty) return; @@ -1441,8 +1448,7 @@ static void do_tty_hangup(struct work_struct *work) /* We may have no line discipline at this point */ if (ld->flush_buffer) ld->flush_buffer(tty); - if (tty->driver->flush_buffer) - tty->driver->flush_buffer(tty); + tty_driver_flush_buffer(tty); if ((test_bit(TTY_DO_WRITE_WAKEUP, &tty->flags)) && ld->write_wakeup) ld->write_wakeup(tty); @@ -1480,19 +1486,24 @@ static void do_tty_hangup(struct work_struct *work) __group_send_sig_info(SIGHUP, SEND_SIG_PRIV, p); __group_send_sig_info(SIGCONT, SEND_SIG_PRIV, p); put_pid(p->signal->tty_old_pgrp); /* A noop */ + spin_lock_irqsave(&tty->ctrl_lock, flags); if (tty->pgrp) p->signal->tty_old_pgrp = get_pid(tty->pgrp); + spin_unlock_irqrestore(&tty->ctrl_lock, flags); spin_unlock_irq(&p->sighand->siglock); } while_each_pid_task(tty->session, PIDTYPE_SID, p); } read_unlock(&tasklist_lock); + spin_lock_irqsave(&tty->ctrl_lock, flags); tty->flags = 0; put_pid(tty->session); put_pid(tty->pgrp); tty->session = NULL; tty->pgrp = NULL; tty->ctrl_status = 0; + spin_unlock_irqrestore(&tty->ctrl_lock, flags); + /* * If one of the devices matches a console pointer, we * cannot just call hangup() because that will cause @@ -1500,11 +1511,11 @@ static void do_tty_hangup(struct work_struct *work) * So we just call close() the right number of times. */ if (cons_filp) { - if (tty->driver->close) + if (tty->ops->close) for (n = 0; n < closecount; n++) - tty->driver->close(tty, cons_filp); - } else if (tty->driver->hangup) - (tty->driver->hangup)(tty); + tty->ops->close(tty, cons_filp); + } else if (tty->ops->hangup) + (tty->ops->hangup)(tty); /* * We don't want to have driver/ldisc interactions beyond * the ones we did here. The driver layer expects no @@ -1626,16 +1637,17 @@ void disassociate_ctty(int on_exit) struct tty_struct *tty; struct pid *tty_pgrp = NULL; - lock_kernel(); mutex_lock(&tty_mutex); tty = get_current_tty(); if (tty) { tty_pgrp = get_pid(tty->pgrp); mutex_unlock(&tty_mutex); + lock_kernel(); /* XXX: here we race, there is nothing protecting tty */ if (on_exit && tty->driver->type != TTY_DRIVER_TYPE_PTY) tty_vhangup(tty); + unlock_kernel(); } else if (on_exit) { struct pid *old_pgrp; spin_lock_irq(¤t->sighand->siglock); @@ -1648,7 +1660,6 @@ void disassociate_ctty(int on_exit) put_pid(old_pgrp); } mutex_unlock(&tty_mutex); - unlock_kernel(); return; } if (tty_pgrp) { @@ -1667,10 +1678,13 @@ void disassociate_ctty(int on_exit) /* It is possible that do_tty_hangup has free'd this tty */ tty = get_current_tty(); if (tty) { + unsigned long flags; + spin_lock_irqsave(&tty->ctrl_lock, flags); put_pid(tty->session); put_pid(tty->pgrp); tty->session = NULL; tty->pgrp = NULL; + spin_unlock_irqrestore(&tty->ctrl_lock, flags); } else { #ifdef TTY_DEBUG_HANGUP printk(KERN_DEBUG "error attempted to write to tty [0x%p]" @@ -1683,7 +1697,6 @@ void disassociate_ctty(int on_exit) read_lock(&tasklist_lock); session_clear_tty(task_session(current)); read_unlock(&tasklist_lock); - unlock_kernel(); } /** @@ -1693,8 +1706,10 @@ void disassociate_ctty(int on_exit) void no_tty(void) { struct task_struct *tsk = current; + lock_kernel(); if (tsk->signal->leader) disassociate_ctty(0); + unlock_kernel(); proc_clear_tty(tsk); } @@ -1714,21 +1729,26 @@ void no_tty(void) * but not always. * * Locking: - * Broken. Relies on BKL which is unsafe here. + * Uses the tty control lock internally */ void stop_tty(struct tty_struct *tty) { - if (tty->stopped) + unsigned long flags; + spin_lock_irqsave(&tty->ctrl_lock, flags); + if (tty->stopped) { + spin_unlock_irqrestore(&tty->ctrl_lock, flags); return; + } tty->stopped = 1; if (tty->link && tty->link->packet) { tty->ctrl_status &= ~TIOCPKT_START; tty->ctrl_status |= TIOCPKT_STOP; wake_up_interruptible(&tty->link->read_wait); } - if (tty->driver->stop) - (tty->driver->stop)(tty); + spin_unlock_irqrestore(&tty->ctrl_lock, flags); + if (tty->ops->stop) + (tty->ops->stop)(tty); } EXPORT_SYMBOL(stop_tty); @@ -1743,21 +1763,26 @@ EXPORT_SYMBOL(stop_tty); * driver start method is invoked and the line discipline woken. * * Locking: - * Broken. Relies on BKL which is unsafe here. + * ctrl_lock */ void start_tty(struct tty_struct *tty) { - if (!tty->stopped || tty->flow_stopped) + unsigned long flags; + spin_lock_irqsave(&tty->ctrl_lock, flags); + if (!tty->stopped || tty->flow_stopped) { + spin_unlock_irqrestore(&tty->ctrl_lock, flags); return; + } tty->stopped = 0; if (tty->link && tty->link->packet) { tty->ctrl_status &= ~TIOCPKT_STOP; tty->ctrl_status |= TIOCPKT_START; wake_up_interruptible(&tty->link->read_wait); } - if (tty->driver->start) - (tty->driver->start)(tty); + spin_unlock_irqrestore(&tty->ctrl_lock, flags); + if (tty->ops->start) + (tty->ops->start)(tty); /* If we have a running line discipline it may need kicking */ tty_wakeup(tty); } @@ -1775,10 +1800,8 @@ EXPORT_SYMBOL(start_tty); * for hung up devices before calling the line discipline method. * * Locking: - * Locks the line discipline internally while needed - * For historical reasons the line discipline read method is - * invoked under the BKL. This will go away in time so do not rely on it - * in new code. Multiple read calls may be outstanding in parallel. + * Locks the line discipline internally while needed. Multiple + * read calls may be outstanding in parallel. */ static ssize_t tty_read(struct file *file, char __user *buf, size_t count, @@ -1799,13 +1822,11 @@ static ssize_t tty_read(struct file *file, char __user *buf, size_t count, /* We want to wait for the line discipline to sort out in this situation */ ld = tty_ldisc_ref_wait(tty); - lock_kernel(); if (ld->read) i = (ld->read)(tty, file, buf, count); else i = -EIO; tty_ldisc_deref(ld); - unlock_kernel(); if (i > 0) inode->i_atime = current_fs_time(inode->i_sb); return i; @@ -1893,9 +1914,7 @@ static inline ssize_t do_tty_write( ret = -EFAULT; if (copy_from_user(tty->write_buf, buf, size)) break; - lock_kernel(); ret = write(tty, file, tty->write_buf, size); - unlock_kernel(); if (ret <= 0) break; written += ret; @@ -1948,10 +1967,13 @@ static ssize_t tty_write(struct file *file, const char __user *buf, tty = (struct tty_struct *)file->private_data; if (tty_paranoia_check(tty, inode, "tty_write")) return -EIO; - if (!tty || !tty->driver->write || + if (!tty || !tty->ops->write || (test_bit(TTY_IO_ERROR, &tty->flags))) return -EIO; - + /* Short term debug to catch buggy drivers */ + if (tty->ops->write_room == NULL) + printk(KERN_ERR "tty driver %s lacks a write_room method.\n", + tty->driver->name); ld = tty_ldisc_ref_wait(tty); if (!ld->write) ret = -EIO; @@ -2098,6 +2120,7 @@ static int init_dev(struct tty_driver *driver, int idx, goto fail_no_mem; initialize_tty_struct(tty); tty->driver = driver; + tty->ops = driver->ops; tty->index = idx; tty_line_name(driver, idx, tty->name); @@ -2128,6 +2151,7 @@ static int init_dev(struct tty_driver *driver, int idx, goto free_mem_out; initialize_tty_struct(o_tty); o_tty->driver = driver->other; + o_tty->ops = driver->ops; o_tty->index = idx; tty_line_name(driver->other, idx, o_tty->name); @@ -2432,8 +2456,8 @@ static void release_dev(struct file *filp) } } #endif - if (tty->driver->close) - tty->driver->close(tty, filp); + if (tty->ops->close) + tty->ops->close(tty, filp); /* * Sanity check: if tty->count is going to zero, there shouldn't be @@ -2612,15 +2636,9 @@ static void release_dev(struct file *filp) */ release_tty(tty, idx); -#ifdef CONFIG_UNIX98_PTYS /* Make this pty number available for reallocation */ - if (devpts) { - mutex_lock(&allocated_ptys_lock); - idr_remove(&allocated_ptys, idx); - mutex_unlock(&allocated_ptys_lock); - } -#endif - + if (devpts) + devpts_kill_index(idx); } /** @@ -2716,8 +2734,8 @@ got_driver: printk(KERN_DEBUG "opening %s...", tty->name); #endif if (!retval) { - if (tty->driver->open) - retval = tty->driver->open(tty, filp); + if (tty->ops->open) + retval = tty->ops->open(tty, filp); else retval = -ENODEV; } @@ -2755,7 +2773,6 @@ got_driver: __proc_set_tty(current, tty); spin_unlock_irq(¤t->sighand->siglock); mutex_unlock(&tty_mutex); - tty_audit_opening(); return 0; } @@ -2777,29 +2794,13 @@ static int ptmx_open(struct inode *inode, struct file *filp) struct tty_struct *tty; int retval; int index; - int idr_ret; nonseekable_open(inode, filp); /* find a device that is not in use. */ - mutex_lock(&allocated_ptys_lock); - if (!idr_pre_get(&allocated_ptys, GFP_KERNEL)) { - mutex_unlock(&allocated_ptys_lock); - return -ENOMEM; - } - idr_ret = idr_get_new(&allocated_ptys, NULL, &index); - if (idr_ret < 0) { - mutex_unlock(&allocated_ptys_lock); - if (idr_ret == -EAGAIN) - return -ENOMEM; - return -EIO; - } - if (index >= pty_limit) { - idr_remove(&allocated_ptys, index); - mutex_unlock(&allocated_ptys_lock); - return -EIO; - } - mutex_unlock(&allocated_ptys_lock); + index = devpts_new_index(); + if (index < 0) + return index; mutex_lock(&tty_mutex); retval = init_dev(ptm_driver, index, &tty); @@ -2812,23 +2813,19 @@ static int ptmx_open(struct inode *inode, struct file *filp) filp->private_data = tty; file_move(filp, &tty->tty_files); - retval = -ENOMEM; - if (devpts_pty_new(tty->link)) + retval = devpts_pty_new(tty->link); + if (retval) goto out1; - check_tty_count(tty, "tty_open"); - retval = ptm_driver->open(tty, filp); - if (!retval) { - tty_audit_opening(); + check_tty_count(tty, "ptmx_open"); + retval = ptm_driver->ops->open(tty, filp); + if (!retval) return 0; - } out1: release_dev(filp); return retval; out: - mutex_lock(&allocated_ptys_lock); - idr_remove(&allocated_ptys, index); - mutex_unlock(&allocated_ptys_lock); + devpts_kill_index(index); return retval; } #endif @@ -2885,6 +2882,7 @@ static unsigned int tty_poll(struct file *filp, poll_table *wait) static int tty_fasync(int fd, struct file *filp, int on) { struct tty_struct *tty; + unsigned long flags; int retval; tty = (struct tty_struct *)filp->private_data; @@ -2900,6 +2898,7 @@ static int tty_fasync(int fd, struct file *filp, int on) struct pid *pid; if (!waitqueue_active(&tty->read_wait)) tty->minimum_to_wake = 1; + spin_lock_irqsave(&tty->ctrl_lock, flags); if (tty->pgrp) { pid = tty->pgrp; type = PIDTYPE_PGID; @@ -2907,6 +2906,7 @@ static int tty_fasync(int fd, struct file *filp, int on) pid = task_pid(current); type = PIDTYPE_PID; } + spin_unlock_irqrestore(&tty->ctrl_lock, flags); retval = __f_setown(filp, pid, type, 0); if (retval) return retval; @@ -2992,6 +2992,8 @@ static int tiocswinsz(struct tty_struct *tty, struct tty_struct *real_tty, struct winsize __user *arg) { struct winsize tmp_ws; + struct pid *pgrp, *rpgrp; + unsigned long flags; if (copy_from_user(&tmp_ws, arg, sizeof(*arg))) return -EFAULT; @@ -3009,10 +3011,21 @@ static int tiocswinsz(struct tty_struct *tty, struct tty_struct *real_tty, } } #endif - if (tty->pgrp) - kill_pgrp(tty->pgrp, SIGWINCH, 1); - if ((real_tty->pgrp != tty->pgrp) && real_tty->pgrp) - kill_pgrp(real_tty->pgrp, SIGWINCH, 1); + /* Get the PID values and reference them so we can + avoid holding the tty ctrl lock while sending signals */ + spin_lock_irqsave(&tty->ctrl_lock, flags); + pgrp = get_pid(tty->pgrp); + rpgrp = get_pid(real_tty->pgrp); + spin_unlock_irqrestore(&tty->ctrl_lock, flags); + + if (pgrp) + kill_pgrp(pgrp, SIGWINCH, 1); + if (rpgrp != pgrp && rpgrp) + kill_pgrp(rpgrp, SIGWINCH, 1); + + put_pid(pgrp); + put_pid(rpgrp); + tty->winsize = tmp_ws; real_tty->winsize = tmp_ws; done: @@ -3073,10 +3086,13 @@ static int fionbio(struct file *file, int __user *p) if (get_user(nonblock, p)) return -EFAULT; + /* file->f_flags is still BKL protected in the fs layer - vomit */ + lock_kernel(); if (nonblock) file->f_flags |= O_NONBLOCK; else file->f_flags &= ~O_NONBLOCK; + unlock_kernel(); return 0; } @@ -3134,6 +3150,27 @@ unlock: } /** + * tty_get_pgrp - return a ref counted pgrp pid + * @tty: tty to read + * + * Returns a refcounted instance of the pid struct for the process + * group controlling the tty. + */ + +struct pid *tty_get_pgrp(struct tty_struct *tty) +{ + unsigned long flags; + struct pid *pgrp; + + spin_lock_irqsave(&tty->ctrl_lock, flags); + pgrp = get_pid(tty->pgrp); + spin_unlock_irqrestore(&tty->ctrl_lock, flags); + + return pgrp; +} +EXPORT_SYMBOL_GPL(tty_get_pgrp); + +/** * tiocgpgrp - get process group * @tty: tty passed by user * @real_tty: tty side of the tty pased by the user if a pty else the tty @@ -3147,13 +3184,18 @@ unlock: static int tiocgpgrp(struct tty_struct *tty, struct tty_struct *real_tty, pid_t __user *p) { + struct pid *pid; + int ret; /* * (tty == real_tty) is a cheap way of * testing if the tty is NOT a master pty. */ if (tty == real_tty && current->signal->tty != real_tty) return -ENOTTY; - return put_user(pid_vnr(real_tty->pgrp), p); + pid = tty_get_pgrp(real_tty); + ret = put_user(pid_vnr(pid), p); + put_pid(pid); + return ret; } /** @@ -3165,7 +3207,7 @@ static int tiocgpgrp(struct tty_struct *tty, struct tty_struct *real_tty, pid_t * Set the process group of the tty to the session passed. Only * permitted where the tty session is our session. * - * Locking: None + * Locking: RCU, ctrl lock */ static int tiocspgrp(struct tty_struct *tty, struct tty_struct *real_tty, pid_t __user *p) @@ -3173,6 +3215,7 @@ static int tiocspgrp(struct tty_struct *tty, struct tty_struct *real_tty, pid_t struct pid *pgrp; pid_t pgrp_nr; int retval = tty_check_change(real_tty); + unsigned long flags; if (retval == -EIO) return -ENOTTY; @@ -3195,8 +3238,10 @@ static int tiocspgrp(struct tty_struct *tty, struct tty_struct *real_tty, pid_t if (session_of_pgrp(pgrp) != task_session(current)) goto out_unlock; retval = 0; + spin_lock_irqsave(&tty->ctrl_lock, flags); put_pid(real_tty->pgrp); real_tty->pgrp = get_pid(pgrp); + spin_unlock_irqrestore(&tty->ctrl_lock, flags); out_unlock: rcu_read_unlock(); return retval; @@ -3240,10 +3285,16 @@ static int tiocgsid(struct tty_struct *tty, struct tty_struct *real_tty, pid_t _ static int tiocsetd(struct tty_struct *tty, int __user *p) { int ldisc; + int ret; if (get_user(ldisc, p)) return -EFAULT; - return tty_set_ldisc(tty, ldisc); + + lock_kernel(); + ret = tty_set_ldisc(tty, ldisc); + unlock_kernel(); + + return ret; } /** @@ -3263,18 +3314,18 @@ static int send_break(struct tty_struct *tty, unsigned int duration) { if (tty_write_lock(tty, 0) < 0) return -EINTR; - tty->driver->break_ctl(tty, -1); + tty->ops->break_ctl(tty, -1); if (!signal_pending(current)) msleep_interruptible(duration); - tty->driver->break_ctl(tty, 0); + tty->ops->break_ctl(tty, 0); tty_write_unlock(tty); - if (signal_pending(current)) + if (!signal_pending(current)) return -EINTR; return 0; } /** - * tiocmget - get modem status + * tty_tiocmget - get modem status * @tty: tty device * @file: user file pointer * @p: pointer to result @@ -3289,8 +3340,8 @@ static int tty_tiocmget(struct tty_struct *tty, struct file *file, int __user *p { int retval = -EINVAL; - if (tty->driver->tiocmget) { - retval = tty->driver->tiocmget(tty, file); + if (tty->ops->tiocmget) { + retval = tty->ops->tiocmget(tty, file); if (retval >= 0) retval = put_user(retval, p); @@ -3299,7 +3350,7 @@ static int tty_tiocmget(struct tty_struct *tty, struct file *file, int __user *p } /** - * tiocmset - set modem status + * tty_tiocmset - set modem status * @tty: tty device * @file: user file pointer * @cmd: command - clear bits, set bits or set all @@ -3316,7 +3367,7 @@ static int tty_tiocmset(struct tty_struct *tty, struct file *file, unsigned int { int retval = -EINVAL; - if (tty->driver->tiocmset) { + if (tty->ops->tiocmset) { unsigned int set, clear, val; retval = get_user(val, p); @@ -3340,7 +3391,7 @@ static int tty_tiocmset(struct tty_struct *tty, struct file *file, unsigned int set &= TIOCM_DTR|TIOCM_RTS|TIOCM_OUT1|TIOCM_OUT2|TIOCM_LOOP; clear &= TIOCM_DTR|TIOCM_RTS|TIOCM_OUT1|TIOCM_OUT2|TIOCM_LOOP; - retval = tty->driver->tiocmset(tty, file, set, clear); + retval = tty->ops->tiocmset(tty, file, set, clear); } return retval; } @@ -3348,20 +3399,18 @@ static int tty_tiocmset(struct tty_struct *tty, struct file *file, unsigned int /* * Split this up, as gcc can choke on it otherwise.. */ -int tty_ioctl(struct inode *inode, struct file *file, - unsigned int cmd, unsigned long arg) +long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { struct tty_struct *tty, *real_tty; void __user *p = (void __user *)arg; int retval; struct tty_ldisc *ld; + struct inode *inode = file->f_dentry->d_inode; tty = (struct tty_struct *)file->private_data; if (tty_paranoia_check(tty, inode, "tty_ioctl")) return -EINVAL; - /* CHECKME: is this safe as one end closes ? */ - real_tty = tty; if (tty->driver->type == TTY_DRIVER_TYPE_PTY && tty->driver->subtype == PTY_TYPE_MASTER) @@ -3370,21 +3419,28 @@ int tty_ioctl(struct inode *inode, struct file *file, /* * Break handling by driver */ - if (!tty->driver->break_ctl) { + + retval = -EINVAL; + + if (!tty->ops->break_ctl) { switch (cmd) { case TIOCSBRK: case TIOCCBRK: - if (tty->driver->ioctl) - return tty->driver->ioctl(tty, file, cmd, arg); - return -EINVAL; + if (tty->ops->ioctl) + retval = tty->ops->ioctl(tty, file, cmd, arg); + if (retval != -EINVAL && retval != -ENOIOCTLCMD) + printk(KERN_WARNING "tty: driver %s needs updating to use break_ctl\n", tty->driver->name); + return retval; /* These two ioctl's always return success; even if */ /* the driver doesn't support them. */ case TCSBRK: case TCSBRKP: - if (!tty->driver->ioctl) + if (!tty->ops->ioctl) return 0; - retval = tty->driver->ioctl(tty, file, cmd, arg); + retval = tty->ops->ioctl(tty, file, cmd, arg); + if (retval != -EINVAL && retval != -ENOIOCTLCMD) + printk(KERN_WARNING "tty: driver %s needs updating to use break_ctl\n", tty->driver->name); if (retval == -ENOIOCTLCMD) retval = 0; return retval; @@ -3442,7 +3498,6 @@ int tty_ioctl(struct inode *inode, struct file *file, case TIOCGSID: return tiocgsid(tty, real_tty, p); case TIOCGETD: - /* FIXME: check this is ok */ return put_user(tty->ldisc.num, (int __user *)p); case TIOCSETD: return tiocsetd(tty, p); @@ -3454,11 +3509,13 @@ int tty_ioctl(struct inode *inode, struct file *file, * Break handling */ case TIOCSBRK: /* Turn break on, unconditionally */ - tty->driver->break_ctl(tty, -1); + if (tty->ops->break_ctl) + tty->ops->break_ctl(tty, -1); return 0; case TIOCCBRK: /* Turn break off, unconditionally */ - tty->driver->break_ctl(tty, 0); + if (tty->ops->break_ctl) + tty->ops->break_ctl(tty, 0); return 0; case TCSBRK: /* SVID version: non-zero arg --> no break */ /* non-zero arg means wait for all output data @@ -3487,8 +3544,8 @@ int tty_ioctl(struct inode *inode, struct file *file, } break; } - if (tty->driver->ioctl) { - retval = (tty->driver->ioctl)(tty, file, cmd, arg); + if (tty->ops->ioctl) { + retval = (tty->ops->ioctl)(tty, file, cmd, arg); if (retval != -ENOIOCTLCMD) return retval; } @@ -3515,8 +3572,8 @@ static long tty_compat_ioctl(struct file *file, unsigned int cmd, if (tty_paranoia_check(tty, inode, "tty_ioctl")) return -EINVAL; - if (tty->driver->compat_ioctl) { - retval = (tty->driver->compat_ioctl)(tty, file, cmd, arg); + if (tty->ops->compat_ioctl) { + retval = (tty->ops->compat_ioctl)(tty, file, cmd, arg); if (retval != -ENOIOCTLCMD) return retval; } @@ -3566,8 +3623,7 @@ void __do_SAK(struct tty_struct *tty) tty_ldisc_flush(tty); - if (tty->driver->flush_buffer) - tty->driver->flush_buffer(tty); + tty_driver_flush_buffer(tty); read_lock(&tasklist_lock); /* Kill the entire session */ @@ -3773,19 +3829,32 @@ static void initialize_tty_struct(struct tty_struct *tty) mutex_init(&tty->atomic_read_lock); mutex_init(&tty->atomic_write_lock); spin_lock_init(&tty->read_lock); + spin_lock_init(&tty->ctrl_lock); INIT_LIST_HEAD(&tty->tty_files); INIT_WORK(&tty->SAK_work, do_SAK_work); } -/* - * The default put_char routine if the driver did not define one. +/** + * tty_put_char - write one character to a tty + * @tty: tty + * @ch: character + * + * Write one byte to the tty using the provided put_char method + * if present. Returns the number of characters successfully output. + * + * Note: the specific put_char operation in the driver layer may go + * away soon. Don't call it directly, use this method */ -static void tty_default_put_char(struct tty_struct *tty, unsigned char ch) +int tty_put_char(struct tty_struct *tty, unsigned char ch) { - tty->driver->write(tty, &ch, 1); + if (tty->ops->put_char) + return tty->ops->put_char(tty, ch); + return tty->ops->write(tty, &ch, 1); } +EXPORT_SYMBOL_GPL(tty_put_char); + static struct class *tty_class; /** @@ -3868,37 +3937,8 @@ void put_tty_driver(struct tty_driver *driver) void tty_set_operations(struct tty_driver *driver, const struct tty_operations *op) { - driver->open = op->open; - driver->close = op->close; - driver->write = op->write; - driver->put_char = op->put_char; - driver->flush_chars = op->flush_chars; - driver->write_room = op->write_room; - driver->chars_in_buffer = op->chars_in_buffer; - driver->ioctl = op->ioctl; - driver->compat_ioctl = op->compat_ioctl; - driver->set_termios = op->set_termios; - driver->throttle = op->throttle; - driver->unthrottle = op->unthrottle; - driver->stop = op->stop; - driver->start = op->start; - driver->hangup = op->hangup; - driver->break_ctl = op->break_ctl; - driver->flush_buffer = op->flush_buffer; - driver->set_ldisc = op->set_ldisc; - driver->wait_until_sent = op->wait_until_sent; - driver->send_xchar = op->send_xchar; - driver->read_proc = op->read_proc; - driver->write_proc = op->write_proc; - driver->tiocmget = op->tiocmget; - driver->tiocmset = op->tiocmset; -#ifdef CONFIG_CONSOLE_POLL - driver->poll_init = op->poll_init; - driver->poll_get_char = op->poll_get_char; - driver->poll_put_char = op->poll_put_char; -#endif -} - + driver->ops = op; +}; EXPORT_SYMBOL(alloc_tty_driver); EXPORT_SYMBOL(put_tty_driver); @@ -3961,9 +4001,6 @@ int tty_register_driver(struct tty_driver *driver) return error; } - if (!driver->put_char) - driver->put_char = tty_default_put_char; - mutex_lock(&tty_mutex); list_add(&driver->tty_drivers, &tty_drivers); mutex_unlock(&tty_mutex); @@ -4039,14 +4076,19 @@ void proc_clear_tty(struct task_struct *p) } EXPORT_SYMBOL(proc_clear_tty); +/* Called under the sighand lock */ + static void __proc_set_tty(struct task_struct *tsk, struct tty_struct *tty) { if (tty) { - /* We should not have a session or pgrp to here but.... */ + unsigned long flags; + /* We should not have a session or pgrp to put here but.... */ + spin_lock_irqsave(&tty->ctrl_lock, flags); put_pid(tty->session); put_pid(tty->pgrp); - tty->session = get_pid(task_session(tsk)); tty->pgrp = get_pid(task_pgrp(tsk)); + spin_unlock_irqrestore(&tty->ctrl_lock, flags); + tty->session = get_pid(task_session(tsk)); } put_pid(tsk->signal->tty_old_pgrp); tsk->signal->tty = tty; |