From 8977d929e49021d9a6e031310aab01fa72f849c2 Mon Sep 17 00:00:00 2001 From: Paul Fulghum Date: Fri, 10 Feb 2006 01:51:14 -0800 Subject: [PATCH] tty buffering stall fix Prevent stalled processing of received data when a driver allocates tty buffer space but does not immediately follow the allocation with more data and a call to schedule receive tty processing. (example: hvc_console) This bug was introduced by the first locking patch for the new tty buffering. Signed-off-by: Paul Fulghum Cc: Alan Cox Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/kbd_kern.h | 4 +++- include/linux/tty.h | 2 ++ include/linux/tty_flip.h | 4 +++- 3 files changed, 8 insertions(+), 2 deletions(-) (limited to 'include/linux') diff --git a/include/linux/kbd_kern.h b/include/linux/kbd_kern.h index 3aed37314ab..e87c32a5c86 100644 --- a/include/linux/kbd_kern.h +++ b/include/linux/kbd_kern.h @@ -153,8 +153,10 @@ static inline void con_schedule_flip(struct tty_struct *t) { unsigned long flags; spin_lock_irqsave(&t->buf.lock, flags); - if (t->buf.tail != NULL) + if (t->buf.tail != NULL) { t->buf.tail->active = 0; + t->buf.tail->commit = t->buf.tail->used; + } spin_unlock_irqrestore(&t->buf.lock, flags); schedule_work(&t->buf.work); } diff --git a/include/linux/tty.h b/include/linux/tty.h index a7bd3b4558d..f45cd74e6f2 100644 --- a/include/linux/tty.h +++ b/include/linux/tty.h @@ -58,6 +58,8 @@ struct tty_buffer { int used; int size; int active; + int commit; + int read; /* Data points here */ unsigned long data[0]; }; diff --git a/include/linux/tty_flip.h b/include/linux/tty_flip.h index 82961eb1988..222faf97d5f 100644 --- a/include/linux/tty_flip.h +++ b/include/linux/tty_flip.h @@ -29,8 +29,10 @@ _INLINE_ void tty_schedule_flip(struct tty_struct *tty) { unsigned long flags; spin_lock_irqsave(&tty->buf.lock, flags); - if (tty->buf.tail != NULL) + if (tty->buf.tail != NULL) { tty->buf.tail->active = 0; + tty->buf.tail->commit = tty->buf.tail->used; + } spin_unlock_irqrestore(&tty->buf.lock, flags); schedule_delayed_work(&tty->buf.work, 1); } -- cgit v1.2.3-70-g09d2