vhost: add vhost_worker pointer to vhost_virtqueue

This patchset allows userspace to map vqs to different workers. This
patch adds a worker pointer to the vq so in later patches in this set
we can queue/flush specific vqs and their workers.

Signed-off-by: Mike Christie <michael.christie@oracle.com>
Message-Id: <20230626232307.97930-4-michael.christie@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
index dfd96cf6a152254a10890c593b2d893328557a4b..db88464c1691c5f994d773457bfa09339612f731 100644 (file)
--- a/drivers/vhost/vhost.c
+++ b/drivers/vhost/vhost.c
@@ -333,6 +333,7 @@ static void vhost_vq_reset(struct vhost_dev *dev,
        vq->busyloop_timeout = 0;
        vq->umem = NULL;
        vq->iotlb = NULL;
+       vq->worker = NULL;
        vhost_vring_call_reset(&vq->call_ctx);
        __vhost_vq_meta_reset(vq);
 }
@@ -545,7 +546,7 @@ static void vhost_worker_free(struct vhost_dev *dev)
        dev->worker = NULL;
 }
 
-static int vhost_worker_create(struct vhost_dev *dev)
+static struct vhost_worker *vhost_worker_create(struct vhost_dev *dev)
 {
        struct vhost_worker *worker;
        struct vhost_task *vtsk;
@@ -553,7 +554,7 @@ static int vhost_worker_create(struct vhost_dev *dev)
 
        worker = kzalloc(sizeof(*worker), GFP_KERNEL_ACCOUNT);
        if (!worker)
-               return -ENOMEM;
+               return NULL;
 
        snprintf(name, sizeof(name), "vhost-%d", current->pid);
 
@@ -572,17 +573,18 @@ static int vhost_worker_create(struct vhost_dev *dev)
        dev->worker = worker;
 
        vhost_task_start(vtsk);
-       return 0;
+       return worker;
 
 free_worker:
        kfree(worker);
-       return -ENOMEM;
+       return NULL;
 }
 
 /* Caller should have device mutex */
 long vhost_dev_set_owner(struct vhost_dev *dev)
 {
-       int err;
+       struct vhost_worker *worker;
+       int err, i;
 
        /* Is there an owner already? */
        if (vhost_dev_has_owner(dev)) {
@@ -603,9 +605,14 @@ long vhost_dev_set_owner(struct vhost_dev *dev)
                 * below since we don't have to worry about vsock queueing
                 * while we free the worker.
                 */
-               err = vhost_worker_create(dev);
-               if (err)
+               worker = vhost_worker_create(dev);
+               if (!worker) {
+                       err = -ENOMEM;
                        goto err_worker;
+               }
+
+               for (i = 0; i < dev->nvqs; i++)
+                       dev->vqs[i]->worker = worker;
        }
 
        return 0;

diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h
index cb872cc4157a7487f7464d8b00058b13e1d8a0e2..206617edb2a9429d5843e645015b366a2fa6d2b4 100644 (file)
--- a/drivers/vhost/vhost.h
+++ b/drivers/vhost/vhost.h
@@ -74,6 +74,7 @@ struct vhost_vring_call {
 /* The virtqueue structure describes a queue attached to a device. */
 struct vhost_virtqueue {
        struct vhost_dev *dev;
+       struct vhost_worker *worker;
 
        /* The actual ring of buffers. */
        struct mutex mutex;