From daea440215ae86bf9fdfe82420710ae749eb73c7 Mon Sep 17 00:00:00 2001 From: Jiri Slaby Date: Mon, 2 Apr 2012 13:54:30 +0200 Subject: [PATCH] TTY: hvsi, use tty from tty_port Now, we switch to the refcounted model and do not need hp->lock to protect hp->tty anymore. Signed-off-by: Jiri Slaby Cc: linuxppc-dev@lists.ozlabs.org Signed-off-by: Greg Kroah-Hartman --- drivers/tty/hvc/hvsi.c | 35 +++++++++++++++++++++-------------- 1 file changed, 21 insertions(+), 14 deletions(-) diff --git a/drivers/tty/hvc/hvsi.c b/drivers/tty/hvc/hvsi.c index 68b729b8d1eb..6f5bc49c441f 100644 --- a/drivers/tty/hvc/hvsi.c +++ b/drivers/tty/hvc/hvsi.c @@ -76,7 +76,6 @@ struct hvsi_struct { wait_queue_head_t stateq; /* woken when HVSI state changes */ spinlock_t lock; int index; - struct tty_struct *tty; uint8_t throttle_buf[128]; uint8_t outbuf[N_OUTBUF]; /* to implement write_room and chars_in_buffer */ /* inbuf is for packet reassembly. leave a little room for leftovers. */ @@ -492,14 +491,17 @@ static irqreturn_t hvsi_interrupt(int irq, void *arg) { struct hvsi_struct *hp = (struct hvsi_struct *)arg; struct hvsi_struct *handshake; + struct tty_struct *tty; unsigned long flags; int again = 1; pr_debug("%s\n", __func__); + tty = tty_port_tty_get(&hp->port); + while (again) { spin_lock_irqsave(&hp->lock, flags); - again = hvsi_load_chunk(hp, hp->tty, &handshake); + again = hvsi_load_chunk(hp, tty, &handshake); spin_unlock_irqrestore(&hp->lock, flags); if (handshake) { @@ -509,15 +511,16 @@ static irqreturn_t hvsi_interrupt(int irq, void *arg) } spin_lock_irqsave(&hp->lock, flags); - if (hp->tty && hp->n_throttle - && (!test_bit(TTY_THROTTLED, &hp->tty->flags))) { - /* we weren't hung up and we weren't throttled, so we can deliver the - * rest now */ - hvsi_send_overflow(hp, hp->tty); - tty_flip_buffer_push(hp->tty); + if (tty && hp->n_throttle && !test_bit(TTY_THROTTLED, &tty->flags)) { + /* we weren't hung up and we weren't throttled, so we can + * deliver the rest now */ + hvsi_send_overflow(hp, tty); + tty_flip_buffer_push(tty); } spin_unlock_irqrestore(&hp->lock, flags); + tty_kref_put(tty); + return IRQ_HANDLED; } @@ -724,8 +727,8 @@ static int hvsi_open(struct tty_struct *tty, struct file *filp) if (hp->state == HVSI_FSP_DIED) return -EIO; + tty_port_tty_set(&hp->port, tty); spin_lock_irqsave(&hp->lock, flags); - hp->tty = tty; hp->port.count++; atomic_set(&hp->seqno, 0); h_vio_signal(hp->vtermno, VIO_IRQ_ENABLE); @@ -784,7 +787,7 @@ static void hvsi_close(struct tty_struct *tty, struct file *filp) spin_lock_irqsave(&hp->lock, flags); if (--hp->port.count == 0) { - hp->tty = NULL; + tty_port_tty_set(&hp->port, NULL); hp->inbuf_end = hp->inbuf; /* discard remaining partial packets */ /* only close down connection if it is not the console */ @@ -830,12 +833,11 @@ static void hvsi_hangup(struct tty_struct *tty) pr_debug("%s\n", __func__); - spin_lock_irqsave(&hp->lock, flags); + tty_port_tty_set(&hp->port, NULL); + spin_lock_irqsave(&hp->lock, flags); hp->port.count = 0; hp->n_outbuf = 0; - hp->tty = NULL; - spin_unlock_irqrestore(&hp->lock, flags); } @@ -863,6 +865,7 @@ static void hvsi_write_worker(struct work_struct *work) { struct hvsi_struct *hp = container_of(work, struct hvsi_struct, writer.work); + struct tty_struct *tty; unsigned long flags; #ifdef DEBUG static long start_j = 0; @@ -896,7 +899,11 @@ static void hvsi_write_worker(struct work_struct *work) start_j = 0; #endif /* DEBUG */ wake_up_all(&hp->emptyq); - tty_wakeup(hp->tty); + tty = tty_port_tty_get(&hp->port); + if (tty) { + tty_wakeup(tty); + tty_kref_put(tty); + } } out: