From 5f378455c5da7403c2300f3470c0b491b9da9bd6 Mon Sep 17 00:00:00 2001
From: Amit Shah <amit.shah@redhat.com>
Date: Thu, 22 Dec 2011 16:58:30 +0530
Subject: [PATCH] --- yaml --- r: 284250 b: refs/heads/master c:
 f8fb5bc23a50a5398aa31a4e8c6dbbef53d2dec6 h: refs/heads/master v: v3

---
 [refs]                           |  2 +-
 trunk/drivers/block/virtio_blk.c | 44 ++++++++++++++++++++++++++++++++
 2 files changed, 45 insertions(+), 1 deletion(-)

diff --git a/[refs] b/[refs]
index 2bd41a9b3b8e..ff9944e53280 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 6abd6e5a4404056e28be04958a57d0286883161a
+refs/heads/master: f8fb5bc23a50a5398aa31a4e8c6dbbef53d2dec6
diff --git a/trunk/drivers/block/virtio_blk.c b/trunk/drivers/block/virtio_blk.c
index e8af52355bf5..ffd5ca919295 100644
--- a/trunk/drivers/block/virtio_blk.c
+++ b/trunk/drivers/block/virtio_blk.c
@@ -588,6 +588,46 @@ static void __devexit virtblk_remove(struct virtio_device *vdev)
 	ida_simple_remove(&vd_index_ida, index);
 }
 
+#ifdef CONFIG_PM
+static int virtblk_freeze(struct virtio_device *vdev)
+{
+	struct virtio_blk *vblk = vdev->priv;
+
+	/* Ensure we don't receive any more interrupts */
+	vdev->config->reset(vdev);
+
+	/* Prevent config work handler from accessing the device. */
+	mutex_lock(&vblk->config_lock);
+	vblk->config_enable = false;
+	mutex_unlock(&vblk->config_lock);
+
+	flush_work(&vblk->config_work);
+
+	spin_lock_irq(vblk->disk->queue->queue_lock);
+	blk_stop_queue(vblk->disk->queue);
+	spin_unlock_irq(vblk->disk->queue->queue_lock);
+	blk_sync_queue(vblk->disk->queue);
+
+	vdev->config->del_vqs(vdev);
+	return 0;
+}
+
+static int virtblk_restore(struct virtio_device *vdev)
+{
+	struct virtio_blk *vblk = vdev->priv;
+	int ret;
+
+	vblk->config_enable = true;
+	ret = init_vq(vdev->priv);
+	if (!ret) {
+		spin_lock_irq(vblk->disk->queue->queue_lock);
+		blk_start_queue(vblk->disk->queue);
+		spin_unlock_irq(vblk->disk->queue->queue_lock);
+	}
+	return ret;
+}
+#endif
+
 static const struct virtio_device_id id_table[] = {
 	{ VIRTIO_ID_BLOCK, VIRTIO_DEV_ANY_ID },
 	{ 0 },
@@ -613,6 +653,10 @@ static struct virtio_driver __refdata virtio_blk = {
 	.probe			= virtblk_probe,
 	.remove			= __devexit_p(virtblk_remove),
 	.config_changed		= virtblk_config_changed,
+#ifdef CONFIG_PM
+	.freeze			= virtblk_freeze,
+	.restore		= virtblk_restore,
+#endif
 };
 
 static int __init init(void)