diff options
Diffstat (limited to 'drivers/char')
| -rw-r--r-- | drivers/char/agp/parisc-agp.c | 2 | ||||
| -rw-r--r-- | drivers/char/n_tty.c | 1 | ||||
| -rw-r--r-- | drivers/char/pty.c | 4 | ||||
| -rw-r--r-- | drivers/char/sysrq.c | 8 | ||||
| -rw-r--r-- | drivers/char/tty_buffer.c | 13 | ||||
| -rw-r--r-- | drivers/char/tty_ldisc.c | 162 | ||||
| -rw-r--r-- | drivers/char/vr41xx_giu.c | 0 |
7 files changed, 82 insertions, 108 deletions
diff --git a/drivers/char/agp/parisc-agp.c b/drivers/char/agp/parisc-agp.c index f4bb43fb801..e077701ae3d 100644 --- a/drivers/char/agp/parisc-agp.c +++ b/drivers/char/agp/parisc-agp.c @@ -225,7 +225,7 @@ static const struct agp_bridge_driver parisc_agp_driver = { .configure = parisc_agp_configure, .fetch_size = parisc_agp_fetch_size, .tlb_flush = parisc_agp_tlbflush, - .mask_memory = parisc_agp_mask_memory, + .mask_memory = parisc_agp_page_mask_memory, .masks = parisc_agp_masks, .agp_enable = parisc_agp_enable, .cache_flush = global_cache_flush, diff --git a/drivers/char/n_tty.c b/drivers/char/n_tty.c index ff47907ff1b..973be2f4419 100644 --- a/drivers/char/n_tty.c +++ b/drivers/char/n_tty.c @@ -1583,6 +1583,7 @@ static int n_tty_open(struct tty_struct *tty) static inline int input_available_p(struct tty_struct *tty, int amt) { + tty_flush_to_ldisc(tty); if (tty->icanon) { if (tty->canon_data) return 1; diff --git a/drivers/char/pty.c b/drivers/char/pty.c index 3850a68f265..d083c73d784 100644 --- a/drivers/char/pty.c +++ b/drivers/char/pty.c @@ -52,7 +52,6 @@ static void pty_close(struct tty_struct *tty, struct file *filp) return; tty->link->packet = 0; set_bit(TTY_OTHER_CLOSED, &tty->link->flags); - tty_flip_buffer_push(tty->link); wake_up_interruptible(&tty->link->read_wait); wake_up_interruptible(&tty->link->write_wait); if (tty->driver->subtype == PTY_TYPE_MASTER) { @@ -145,6 +144,8 @@ static int pty_write(struct tty_struct *tty, const unsigned char *buf, static int pty_write_room(struct tty_struct *tty) { + if (tty->stopped) + return 0; return pty_space(tty->link); } @@ -208,7 +209,6 @@ static int pty_open(struct tty_struct *tty, struct file *filp) clear_bit(TTY_OTHER_CLOSED, &tty->link->flags); set_bit(TTY_THROTTLED, &tty->flags); retval = 0; - tty->low_latency = 1; out: return retval; } diff --git a/drivers/char/sysrq.c b/drivers/char/sysrq.c index 0db35857e4d..5d7a02f63e1 100644 --- a/drivers/char/sysrq.c +++ b/drivers/char/sysrq.c @@ -35,7 +35,6 @@ #include <linux/spinlock.h> #include <linux/vt_kern.h> #include <linux/workqueue.h> -#include <linux/kexec.h> #include <linux/hrtimer.h> #include <linux/oom.h> @@ -124,9 +123,12 @@ static struct sysrq_key_op sysrq_unraw_op = { static void sysrq_handle_crash(int key, struct tty_struct *tty) { char *killer = NULL; + + panic_on_oops = 1; /* force panic */ + wmb(); *killer = 1; } -static struct sysrq_key_op sysrq_crashdump_op = { +static struct sysrq_key_op sysrq_crash_op = { .handler = sysrq_handle_crash, .help_msg = "Crash", .action_msg = "Trigger a crash", @@ -401,7 +403,7 @@ static struct sysrq_key_op *sysrq_key_table[36] = { */ NULL, /* a */ &sysrq_reboot_op, /* b */ - &sysrq_crashdump_op, /* c & ibm_emac driver debug */ + &sysrq_crash_op, /* c & ibm_emac driver debug */ &sysrq_showlocks_op, /* d */ &sysrq_term_op, /* e */ &sysrq_moom_op, /* f */ diff --git a/drivers/char/tty_buffer.c b/drivers/char/tty_buffer.c index 810ee25d66a..3108991c5c8 100644 --- a/drivers/char/tty_buffer.c +++ b/drivers/char/tty_buffer.c @@ -462,6 +462,19 @@ static void flush_to_ldisc(struct work_struct *work) } /** + * tty_flush_to_ldisc + * @tty: tty to push + * + * Push the terminal flip buffers to the line discipline. + * + * Must not be called from IRQ context. + */ +void tty_flush_to_ldisc(struct tty_struct *tty) +{ + flush_to_ldisc(&tty->buf.work.work); +} + +/** * tty_flip_buffer_push - terminal * @tty: tty to push * diff --git a/drivers/char/tty_ldisc.c b/drivers/char/tty_ldisc.c index acd76b767d4..e48af9f7921 100644 --- a/drivers/char/tty_ldisc.c +++ b/drivers/char/tty_ldisc.c @@ -48,6 +48,41 @@ static DECLARE_WAIT_QUEUE_HEAD(tty_ldisc_wait); /* Line disc dispatch table */ static struct tty_ldisc_ops *tty_ldiscs[NR_LDISCS]; +static inline struct tty_ldisc *get_ldisc(struct tty_ldisc *ld) +{ + if (ld) + atomic_inc(&ld->users); + return ld; +} + +static void put_ldisc(struct tty_ldisc *ld) +{ + unsigned long flags; + + if (WARN_ON_ONCE(!ld)) + return; + + /* + * If this is the last user, free the ldisc, and + * release the ldisc ops. + * + * We really want an "atomic_dec_and_lock_irqsave()", + * but we don't have it, so this does it by hand. + */ + local_irq_save(flags); + if (atomic_dec_and_lock(&ld->users, &tty_ldisc_lock)) { + struct tty_ldisc_ops *ldo = ld->ops; + + ldo->refcount--; + module_put(ldo->owner); + spin_unlock_irqrestore(&tty_ldisc_lock, flags); + + kfree(ld); + return; + } + local_irq_restore(flags); +} + /** * tty_register_ldisc - install a line discipline * @disc: ldisc number @@ -142,7 +177,7 @@ static struct tty_ldisc *tty_ldisc_try_get(int disc) /* lock it */ ldops->refcount++; ld->ops = ldops; - ld->refcount = 0; + atomic_set(&ld->users, 1); err = 0; } } @@ -181,35 +216,6 @@ static struct tty_ldisc *tty_ldisc_get(int disc) return ld; } -/** - * tty_ldisc_put - drop ldisc reference - * @ld: ldisc - * - * Drop a reference to a line discipline. Manage refcounts and - * module usage counts. Free the ldisc once the recount hits zero. - * - * Locking: - * takes tty_ldisc_lock to guard against ldisc races - */ - -static void tty_ldisc_put(struct tty_ldisc *ld) -{ - unsigned long flags; - int disc = ld->ops->num; - struct tty_ldisc_ops *ldo; - - BUG_ON(disc < N_TTY || disc >= NR_LDISCS); - - spin_lock_irqsave(&tty_ldisc_lock, flags); - ldo = tty_ldiscs[disc]; - BUG_ON(ldo->refcount == 0); - ldo->refcount--; - module_put(ldo->owner); - spin_unlock_irqrestore(&tty_ldisc_lock, flags); - WARN_ON(ld->refcount); - kfree(ld); -} - static void *tty_ldiscs_seq_start(struct seq_file *m, loff_t *pos) { return (*pos < NR_LDISCS) ? pos : NULL; @@ -234,7 +240,7 @@ static int tty_ldiscs_seq_show(struct seq_file *m, void *v) if (IS_ERR(ld)) return 0; seq_printf(m, "%-10s %2d\n", ld->ops->name ? ld->ops->name : "???", i); - tty_ldisc_put(ld); + put_ldisc(ld); return 0; } @@ -288,20 +294,17 @@ static void tty_ldisc_assign(struct tty_struct *tty, struct tty_ldisc *ld) * Locking: takes tty_ldisc_lock */ -static int tty_ldisc_try(struct tty_struct *tty) +static struct tty_ldisc *tty_ldisc_try(struct tty_struct *tty) { unsigned long flags; struct tty_ldisc *ld; - int ret = 0; spin_lock_irqsave(&tty_ldisc_lock, flags); - ld = tty->ldisc; - if (test_bit(TTY_LDISC, &tty->flags)) { - ld->refcount++; - ret = 1; - } + ld = NULL; + if (test_bit(TTY_LDISC, &tty->flags)) + ld = get_ldisc(tty->ldisc); spin_unlock_irqrestore(&tty_ldisc_lock, flags); - return ret; + return ld; } /** @@ -322,10 +325,11 @@ static int tty_ldisc_try(struct tty_struct *tty) struct tty_ldisc *tty_ldisc_ref_wait(struct tty_struct *tty) { + struct tty_ldisc *ld; + /* wait_event is a macro */ - wait_event(tty_ldisc_wait, tty_ldisc_try(tty)); - WARN_ON(tty->ldisc->refcount == 0); - return tty->ldisc; + wait_event(tty_ldisc_wait, (ld = tty_ldisc_try(tty)) != NULL); + return ld; } EXPORT_SYMBOL_GPL(tty_ldisc_ref_wait); @@ -342,9 +346,7 @@ EXPORT_SYMBOL_GPL(tty_ldisc_ref_wait); struct tty_ldisc *tty_ldisc_ref(struct tty_struct *tty) { - if (tty_ldisc_try(tty)) - return tty->ldisc; - return NULL; + return tty_ldisc_try(tty); } EXPORT_SYMBOL_GPL(tty_ldisc_ref); @@ -360,21 +362,15 @@ EXPORT_SYMBOL_GPL(tty_ldisc_ref); void tty_ldisc_deref(struct tty_ldisc *ld) { - unsigned long flags; - - BUG_ON(ld == NULL); - - spin_lock_irqsave(&tty_ldisc_lock, flags); - if (ld->refcount == 0) - printk(KERN_ERR "tty_ldisc_deref: no references.\n"); - else - ld->refcount--; - if (ld->refcount == 0) - wake_up(&tty_ldisc_wait); - spin_unlock_irqrestore(&tty_ldisc_lock, flags); + put_ldisc(ld); } EXPORT_SYMBOL_GPL(tty_ldisc_deref); +static inline void tty_ldisc_put(struct tty_ldisc *ld) +{ + put_ldisc(ld); +} + /** * tty_ldisc_enable - allow ldisc use * @tty: terminal to activate ldisc on @@ -512,8 +508,9 @@ static void tty_ldisc_restore(struct tty_struct *tty, struct tty_ldisc *old) * be obtained while the delayed work queue halt ensures that no more * data is fed to the ldisc. * - * In order to wait for any existing references to complete see - * tty_ldisc_wait_idle. + * You need to do a 'flush_scheduled_work()' (outside the ldisc_mutex) + * in order to make sure any currently executing ldisc work is also + * flushed. */ static int tty_ldisc_halt(struct tty_struct *tty) @@ -523,31 +520,6 @@ static int tty_ldisc_halt(struct tty_struct *tty) } /** - * tty_ldisc_wait_idle - wait for the ldisc to become idle - * @tty: tty to wait for - * - * Wait for the line discipline to become idle. The discipline must - * have been halted for this to guarantee it remains idle. - * - * tty_ldisc_lock protects the ref counts currently. - */ - -static int tty_ldisc_wait_idle(struct tty_struct *tty) -{ - unsigned long flags; - spin_lock_irqsave(&tty_ldisc_lock, flags); - while (tty->ldisc->refcount) { - spin_unlock_irqrestore(&tty_ldisc_lock, flags); - if (wait_event_timeout(tty_ldisc_wait, - tty->ldisc->refcount == 0, 5 * HZ) == 0) - return -EBUSY; - spin_lock_irqsave(&tty_ldisc_lock, flags); - } - spin_unlock_irqrestore(&tty_ldisc_lock, flags); - return 0; -} - -/** * tty_set_ldisc - set line discipline * @tty: the terminal to set * @ldisc: the line discipline @@ -642,14 +614,6 @@ int tty_set_ldisc(struct tty_struct *tty, int ldisc) flush_scheduled_work(); - /* Let any existing reference holders finish */ - retval = tty_ldisc_wait_idle(tty); - if (retval < 0) { - clear_bit(TTY_LDISC_CHANGING, &tty->flags); - tty_ldisc_put(new_ldisc); - return retval; - } - mutex_lock(&tty->ldisc_mutex); if (test_bit(TTY_HUPPED, &tty->flags)) { /* We were raced by the hangup method. It will have stomped @@ -790,12 +754,14 @@ void tty_ldisc_hangup(struct tty_struct *tty) * N_TTY. */ if (tty->driver->flags & TTY_DRIVER_RESET_TERMIOS) { + /* Make sure the old ldisc is quiescent */ + tty_ldisc_halt(tty); + flush_scheduled_work(); + /* Avoid racing set_ldisc or tty_ldisc_release */ mutex_lock(&tty->ldisc_mutex); if (tty->ldisc) { /* Not yet closed */ /* Switch back to N_TTY */ - tty_ldisc_halt(tty); - tty_ldisc_wait_idle(tty); tty_ldisc_reinit(tty); /* At this point we have a closed ldisc and we want to reopen it. We could defer this to the next open but @@ -860,14 +826,6 @@ void tty_ldisc_release(struct tty_struct *tty, struct tty_struct *o_tty) tty_ldisc_halt(tty); flush_scheduled_work(); - /* - * Wait for any short term users (we know they are just driver - * side waiters as the file is closing so user count on the file - * side is zero. - */ - - tty_ldisc_wait_idle(tty); - mutex_lock(&tty->ldisc_mutex); /* * Now kill off the ldisc diff --git a/drivers/char/vr41xx_giu.c b/drivers/char/vr41xx_giu.c deleted file mode 100644 index e69de29bb2d..00000000000 --- a/drivers/char/vr41xx_giu.c +++ /dev/null |