If the 'nr_ports' variable in the config space is updated to
a higher value, that means new ports have been hotplugged.
Introduce a new workqueue to handle such updates and create
new ports.
Signed-off-by: Amit Shah <amit.shah@xxxxxxxxxx>
---
drivers/char/virtio_console.c | 53 +++++++++++++++++++++++++++++++++++++++++
1 files changed, 53 insertions(+), 0 deletions(-)
diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c
index 4119c37..3458340 100644
--- a/drivers/char/virtio_console.c
+++ b/drivers/char/virtio_console.c
@@ -49,6 +49,7 @@ struct virtio_console_struct {
*/
struct work_struct rx_work;
struct work_struct tx_work;
+ struct work_struct config_work;
struct list_head port_head;
struct list_head unused_read_head;
@@ -869,6 +870,10 @@ static void tx_intr(struct virtqueue *vq)
static void config_intr(struct virtio_device *vdev)
{
+ if (use_multiport(&virtconsole)) {
+ /* Handle port hot-add */
+ schedule_work(&virtconsole.config_work);
+ }
/*
* We'll use this way of resizing only for legacy support. For
* newer userspace (VIRTIO_CONSOLE_F_MULTPORT+), use control
@@ -942,6 +947,53 @@ free_port:
return ret;
}
+/*
+ * The workhandler for config-space updates
+ *
+ * This is used when new ports are added
+ */
+static void virtio_console_config_work_handler(struct work_struct *work)
+{
+ struct virtio_console_struct *vcon;
+ struct virtio_console_config virtconconf;
+ struct virtio_device *vdev;
+ int err;
+
+ vcon = container_of(work, struct virtio_console_struct, config_work);
+
+ vdev = vcon->vdev;
+ vdev->config->get(vdev,
+ offsetof(struct virtio_console_config, nr_ports),
+ &virtconconf.nr_ports,
+ sizeof(virtconconf.nr_ports));
+
+ if (vcon->config.nr_ports == virtconconf.nr_ports) {
+ /*
+ * Port 0 got hot-added. Since we already did all the other
+ * initialisation for it, just ask the Host for the name
+ * if set
+ */
+ struct virtio_console_control cpkt;
+ struct virtio_console_port *port;
+
+ port = get_port_from_id(0);
+ cpkt.event = VIRTIO_CONSOLE_PORT_NAME;
+ send_buf(port, (char *)&cpkt, sizeof(cpkt),
+ VIRTIO_CONSOLE_ID_CONTROL, false);
+ return;
+ }
+ if (virtconconf.nr_ports < vcon->config.nr_ports)
+ return;
+
+ /* Hot-add ports */
+ while(virtconconf.nr_ports - vcon->config.nr_ports) {
+ err = virtconsole_add_port(vcon->config.nr_ports);
+ if (err)
+ break;
+ vcon->config.nr_ports++;
+ }
+}
+
/*D:370
* Once we're further in boot, we get probed like any other virtio device.
* At this stage we set up the output virtqueue.
@@ -1002,6 +1054,7 @@ static int __devinit virtcons_probe(struct virtio_device *vdev)
INIT_WORK(&virtconsole.rx_work, &virtio_console_rx_work_handler);
INIT_WORK(&virtconsole.tx_work, &virtio_console_tx_work_handler);
+ INIT_WORK(&virtconsole.config_work, &virtio_console_config_work_handler);
fill_receive_queue(&virtconsole);
alloc_write_bufs(&virtconsole);
--
1.6.2.5
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