diff options
| -rw-r--r-- | drivers/tty/tty_buffer.c | 16 | ||||
| -rw-r--r-- | include/linux/tty.h | 1 |
2 files changed, 15 insertions, 2 deletions
diff --git a/drivers/tty/tty_buffer.c b/drivers/tty/tty_buffer.c index 8ebd9f88a6f6..f1d30f6945af 100644 --- a/drivers/tty/tty_buffer.c +++ b/drivers/tty/tty_buffer.c @@ -255,11 +255,16 @@ static int __tty_buffer_request_room(struct tty_port *port, size_t size, if (change || left < size) { /* This is the slow path - looking for new buffers to use */ if ((n = tty_buffer_alloc(port, size)) != NULL) { + unsigned long iflags; + n->flags = flags; buf->tail = n; + + spin_lock_irqsave(&buf->flush_lock, iflags); b->commit = b->used; - smp_mb(); b->next = n; + spin_unlock_irqrestore(&buf->flush_lock, iflags); + } else if (change) size = 0; else @@ -443,6 +448,7 @@ static void flush_to_ldisc(struct work_struct *work) mutex_lock(&buf->lock); while (1) { + unsigned long flags; struct tty_buffer *head = buf->head; int count; @@ -450,14 +456,19 @@ static void flush_to_ldisc(struct work_struct *work) if (atomic_read(&buf->priority)) break; + spin_lock_irqsave(&buf->flush_lock, flags); count = head->commit - head->read; if (!count) { - if (head->next == NULL) + if (head->next == NULL) { + spin_unlock_irqrestore(&buf->flush_lock, flags); break; + } buf->head = head->next; + spin_unlock_irqrestore(&buf->flush_lock, flags); tty_buffer_free(port, head); continue; } + spin_unlock_irqrestore(&buf->flush_lock, flags); count = receive_buf(tty, head, count); if (!count) @@ -512,6 +523,7 @@ void tty_buffer_init(struct tty_port *port) struct tty_bufhead *buf = &port->buf; mutex_init(&buf->lock); + spin_lock_init(&buf->flush_lock); tty_buffer_reset(&buf->sentinel, 0); buf->head = &buf->sentinel; buf->tail = &buf->sentinel; diff --git a/include/linux/tty.h b/include/linux/tty.h index 1c3316a47d7e..036cccd80d9f 100644 --- a/include/linux/tty.h +++ b/include/linux/tty.h @@ -61,6 +61,7 @@ struct tty_bufhead { struct tty_buffer *head; /* Queue head */ struct work_struct work; struct mutex lock; + spinlock_t flush_lock; atomic_t priority; struct tty_buffer sentinel; struct llist_head free; /* Free queue head */ |