Merge tag 'for-linus' of git://github.com/rustyrussell/linux

[cascardo/linux.git] / drivers / char / virtio_console.c

diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c
index 8e3c46d..b58b561 100644 (file)
--- a/drivers/char/virtio_console.c
+++ b/drivers/char/virtio_console.c
@@ -392,7 +392,7 @@ static int add_inbuf(struct virtqueue *vq, struct port_buffer *buf)
 
        sg_init_one(sg, buf->buf, buf->size);
 
-       ret = virtqueue_add_buf(vq, sg, 0, 1, buf);
+       ret = virtqueue_add_buf(vq, sg, 0, 1, buf, GFP_ATOMIC);
        virtqueue_kick(vq);
        return ret;
 }
@@ -457,7 +457,7 @@ static ssize_t __send_control_msg(struct ports_device *portdev, u32 port_id,
        vq = portdev->c_ovq;
 
        sg_init_one(sg, &cpkt, sizeof(cpkt));
-       if (virtqueue_add_buf(vq, sg, 1, 0, &cpkt) >= 0) {
+       if (virtqueue_add_buf(vq, sg, 1, 0, &cpkt, GFP_ATOMIC) >= 0) {
                virtqueue_kick(vq);
                while (!virtqueue_get_buf(vq, &len))
                        cpu_relax();
@@ -506,7 +506,7 @@ static ssize_t send_buf(struct port *port, void *in_buf, size_t in_count,
        reclaim_consumed_buffers(port);
 
        sg_init_one(sg, in_buf, in_count);
-       ret = virtqueue_add_buf(out_vq, sg, 1, 0, in_buf);
+       ret = virtqueue_add_buf(out_vq, sg, 1, 0, in_buf, GFP_ATOMIC);
 
        /* Tell Host to go! */
        virtqueue_kick(out_vq);
@@ -1271,6 +1271,20 @@ static void remove_port(struct kref *kref)
        kfree(port);
 }
 
+static void remove_port_data(struct port *port)
+{
+       struct port_buffer *buf;
+
+       /* Remove unused data this port might have received. */
+       discard_port_data(port);
+
+       reclaim_consumed_buffers(port);
+
+       /* Remove buffers we queued up for the Host to send us data in. */
+       while ((buf = virtqueue_detach_unused_buf(port->in_vq)))
+               free_buf(buf);
+}
+
 /*
  * Port got unplugged.  Remove port from portdev's list and drop the
  * kref reference.  If no userspace has this port opened, it will
@@ -1278,8 +1292,6 @@ static void remove_port(struct kref *kref)
  */
 static void unplug_port(struct port *port)
 {
-       struct port_buffer *buf;
-
        spin_lock_irq(&port->portdev->ports_lock);
        list_del(&port->list);
        spin_unlock_irq(&port->portdev->ports_lock);
@@ -1300,14 +1312,7 @@ static void unplug_port(struct port *port)
                hvc_remove(port->cons.hvc);
        }
 
-       /* Remove unused data this port might have received. */
-       discard_port_data(port);
-
-       reclaim_consumed_buffers(port);
-
-       /* Remove buffers we queued up for the Host to send us data in. */
-       while ((buf = virtqueue_detach_unused_buf(port->in_vq)))
-               free_buf(buf);
+       remove_port_data(port);
 
        /*
         * We should just assume the device itself has gone off --
@@ -1659,6 +1664,28 @@ static const struct file_operations portdev_fops = {
        .owner = THIS_MODULE,
 };
 
+static void remove_vqs(struct ports_device *portdev)
+{
+       portdev->vdev->config->del_vqs(portdev->vdev);
+       kfree(portdev->in_vqs);
+       kfree(portdev->out_vqs);
+}
+
+static void remove_controlq_data(struct ports_device *portdev)
+{
+       struct port_buffer *buf;
+       unsigned int len;
+
+       if (!use_multiport(portdev))
+               return;
+
+       while ((buf = virtqueue_get_buf(portdev->c_ivq, &len)))
+               free_buf(buf);
+
+       while ((buf = virtqueue_detach_unused_buf(portdev->c_ivq)))
+               free_buf(buf);
+}
+
 /*
  * Once we're further in boot, we get probed like any other virtio
  * device.
@@ -1764,9 +1791,7 @@ free_vqs:
        /* The host might want to notify mgmt sw about device add failure */
        __send_control_msg(portdev, VIRTIO_CONSOLE_BAD_ID,
                           VIRTIO_CONSOLE_DEVICE_READY, 0);
-       vdev->config->del_vqs(vdev);
-       kfree(portdev->in_vqs);
-       kfree(portdev->out_vqs);
+       remove_vqs(portdev);
 free_chrdev:
        unregister_chrdev(portdev->chr_major, "virtio-portsdev");
 free:
@@ -1804,21 +1829,8 @@ static void virtcons_remove(struct virtio_device *vdev)
         * have to just stop using the port, as the vqs are going
         * away.
         */
-       if (use_multiport(portdev)) {
-               struct port_buffer *buf;
-               unsigned int len;
-
-               while ((buf = virtqueue_get_buf(portdev->c_ivq, &len)))
-                       free_buf(buf);
-
-               while ((buf = virtqueue_detach_unused_buf(portdev->c_ivq)))
-                       free_buf(buf);
-       }
-
-       vdev->config->del_vqs(vdev);
-       kfree(portdev->in_vqs);
-       kfree(portdev->out_vqs);
-
+       remove_controlq_data(portdev);
+       remove_vqs(portdev);
        kfree(portdev);
 }
 
@@ -1832,6 +1844,68 @@ static unsigned int features[] = {
        VIRTIO_CONSOLE_F_MULTIPORT,
 };
 
+#ifdef CONFIG_PM
+static int virtcons_freeze(struct virtio_device *vdev)
+{
+       struct ports_device *portdev;
+       struct port *port;
+
+       portdev = vdev->priv;
+
+       vdev->config->reset(vdev);
+
+       virtqueue_disable_cb(portdev->c_ivq);
+       cancel_work_sync(&portdev->control_work);
+       /*
+        * Once more: if control_work_handler() was running, it would
+        * enable the cb as the last step.
+        */
+       virtqueue_disable_cb(portdev->c_ivq);
+       remove_controlq_data(portdev);
+
+       list_for_each_entry(port, &portdev->ports, list) {
+               virtqueue_disable_cb(port->in_vq);
+               virtqueue_disable_cb(port->out_vq);
+               /*
+                * We'll ask the host later if the new invocation has
+                * the port opened or closed.
+                */
+               port->host_connected = false;
+               remove_port_data(port);
+       }
+       remove_vqs(portdev);
+
+       return 0;
+}
+
+static int virtcons_restore(struct virtio_device *vdev)
+{
+       struct ports_device *portdev;
+       struct port *port;
+       int ret;
+
+       portdev = vdev->priv;
+
+       ret = init_vqs(portdev);
+       if (ret)
+               return ret;
+
+       if (use_multiport(portdev))
+               fill_queue(portdev->c_ivq, &portdev->cvq_lock);
+
+       list_for_each_entry(port, &portdev->ports, list) {
+               port->in_vq = portdev->in_vqs[port->id];
+               port->out_vq = portdev->out_vqs[port->id];
+
+               fill_queue(port->in_vq, &port->inbuf_lock);
+
+               /* Get port open/close status on the host */
+               send_control_msg(port, VIRTIO_CONSOLE_PORT_READY, 1);
+       }
+       return 0;
+}
+#endif
+
 static struct virtio_driver virtio_console = {
        .feature_table = features,
        .feature_table_size = ARRAY_SIZE(features),
@@ -1841,6 +1915,10 @@ static struct virtio_driver virtio_console = {
        .probe =        virtcons_probe,
        .remove =       virtcons_remove,
        .config_changed = config_intr,
+#ifdef CONFIG_PM
+       .freeze =       virtcons_freeze,
+       .restore =      virtcons_restore,
+#endif
 };
 
 static int __init init(void)