[RFC PATCH v2 07/10] drivers/vhost: assign workers to virtqueues

[Andrey Zhadchenko <andrey.zhadchenko@xxxxxxxxxxxxx>]

Add worker pointer to every virtqueue. Add routine to assing
workers to virtqueues and call it after any worker creation

Signed-off-by: Andrey Zhadchenko <andrey.zhadchenko@xxxxxxxxxxxxx>
---
 drivers/vhost/vhost.c | 14 ++++++++++++++
 drivers/vhost/vhost.h |  2 ++
 2 files changed, 16 insertions(+)

diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
index 09e3c4b1bd05..d80831d21fba 100644
--- a/drivers/vhost/vhost.c
+++ b/drivers/vhost/vhost.c
@@ -353,6 +353,7 @@ static void vhost_vq_reset(struct vhost_dev *dev,
 	vq->iotlb = NULL;
 	vhost_vring_call_reset(&vq->call_ctx);
 	__vhost_vq_meta_reset(vq);
+	vq->worker = NULL;
 }
 
 static void vhost_worker_reset(struct vhost_worker *w)
@@ -667,6 +668,17 @@ static int vhost_set_workers(struct vhost_dev *dev, int n)
 	return ret;
 }
 
+static void vhost_assign_workers(struct vhost_dev *dev)
+{
+	int i, j = 0;
+
+	for (i = 0; i < dev->nvqs; i++) {
+		dev->vqs[i]->worker = &dev->workers[j];
+		if (++j == dev->nworkers)
+			j = 0;
+	}
+}
+
 /* Caller should have device mutex */
 long vhost_dev_set_owner(struct vhost_dev *dev)
 {
@@ -689,6 +701,7 @@ long vhost_dev_set_owner(struct vhost_dev *dev)
 	if (err)
 		goto err_worker;
 
+	vhost_assign_workers(dev);
 	return 0;
 err_worker:
 	vhost_cleanup_workers(dev);
@@ -1907,6 +1920,7 @@ long vhost_dev_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *argp)
 		}
 
 		r = vhost_set_workers(d, n);
+		vhost_assign_workers(d);
 		break;
 	default:
 		r = -ENOIOCTLCMD;
diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h
index fc365b08fc38..b9a10c85b298 100644
--- a/drivers/vhost/vhost.h
+++ b/drivers/vhost/vhost.h
@@ -137,6 +137,8 @@ struct vhost_virtqueue {
 	bool user_be;
 #endif
 	u32 busyloop_timeout;
+
+	struct vhost_worker *worker;
 };
 
 struct vhost_msg_node {
-- 
2.31.1