diff options
| -rw-r--r-- | drivers/char/virtio_console.c | 25 |
1 files changed, 25 insertions, 0 deletions
diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c index c84486b3e43..c4ca4369423 100644 --- a/drivers/char/virtio_console.c +++ b/drivers/char/virtio_console.c @@ -196,6 +196,9 @@ struct port { /* The 'name' of the port that we expose via sysfs properties */ char *name; + /* We can notify apps of host connect / disconnect events via SIGIO */ + struct fasync_struct *async_queue; + /* The 'id' to identify the port with the Host */ u32 id; @@ -815,6 +818,14 @@ out: return ret; } +static int port_fops_fasync(int fd, struct file *filp, int mode) +{ + struct port *port; + + port = filp->private_data; + return fasync_helper(fd, filp, mode, &port->async_queue); +} + /* * The file operations that we support: programs in the guest can open * a console device, read from it, write to it, poll for data and @@ -828,6 +839,7 @@ static const struct file_operations port_fops = { .write = port_fops_write, .poll = port_fops_poll, .release = port_fops_release, + .fasync = port_fops_fasync, }; /* @@ -1086,6 +1098,12 @@ static unsigned int fill_queue(struct virtqueue *vq, spinlock_t *lock) return nr_added_bufs; } +static void send_sigio_to_port(struct port *port) +{ + if (port->async_queue && port->guest_connected) + kill_fasync(&port->async_queue, SIGIO, POLL_OUT); +} + static int add_port(struct ports_device *portdev, u32 id) { char debugfs_name[16]; @@ -1108,6 +1126,7 @@ static int add_port(struct ports_device *portdev, u32 id) port->name = NULL; port->inbuf = NULL; port->cons.hvc = NULL; + port->async_queue = NULL; port->cons.ws.ws_row = port->cons.ws.ws_col = 0; @@ -1362,6 +1381,12 @@ static void handle_control_message(struct ports_device *portdev, spin_lock_irq(&port->outvq_lock); reclaim_consumed_buffers(port); spin_unlock_irq(&port->outvq_lock); + + /* + * If the guest is connected, it'll be interested in + * knowing the host connection state changed. + */ + send_sigio_to_port(port); break; case VIRTIO_CONSOLE_PORT_NAME: /* |