Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost
Pull virtio fixes from Michael Tsirkin:
"A couple of bug fixes"
* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
vhost: vsock: kick send_pkt worker once device is started
virtio-blk: handle block_device_operations callbacks after hot unplug
diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c
index 93468b7..9d21bf0 100644
--- a/drivers/block/virtio_blk.c
+++ b/drivers/block/virtio_blk.c
@@ -33,6 +33,15 @@
} ____cacheline_aligned_in_smp;
struct virtio_blk {
+ /*
+ * This mutex must be held by anything that may run after
+ * virtblk_remove() sets vblk->vdev to NULL.
+ *
+ * blk-mq, virtqueue processing, and sysfs attribute code paths are
+ * shut down before vblk->vdev is set to NULL and therefore do not need
+ * to hold this mutex.
+ */
+ struct mutex vdev_mutex;
struct virtio_device *vdev;
/* The disk structure for the kernel. */
@@ -44,6 +53,13 @@
/* Process context for config space updates */
struct work_struct config_work;
+ /*
+ * Tracks references from block_device_operations open/release and
+ * virtio_driver probe/remove so this object can be freed once no
+ * longer in use.
+ */
+ refcount_t refs;
+
/* What host tells us, plus 2 for header & tailer. */
unsigned int sg_elems;
@@ -295,10 +311,55 @@
return err;
}
+static void virtblk_get(struct virtio_blk *vblk)
+{
+ refcount_inc(&vblk->refs);
+}
+
+static void virtblk_put(struct virtio_blk *vblk)
+{
+ if (refcount_dec_and_test(&vblk->refs)) {
+ ida_simple_remove(&vd_index_ida, vblk->index);
+ mutex_destroy(&vblk->vdev_mutex);
+ kfree(vblk);
+ }
+}
+
+static int virtblk_open(struct block_device *bd, fmode_t mode)
+{
+ struct virtio_blk *vblk = bd->bd_disk->private_data;
+ int ret = 0;
+
+ mutex_lock(&vblk->vdev_mutex);
+
+ if (vblk->vdev)
+ virtblk_get(vblk);
+ else
+ ret = -ENXIO;
+
+ mutex_unlock(&vblk->vdev_mutex);
+ return ret;
+}
+
+static void virtblk_release(struct gendisk *disk, fmode_t mode)
+{
+ struct virtio_blk *vblk = disk->private_data;
+
+ virtblk_put(vblk);
+}
+
/* We provide getgeo only to please some old bootloader/partitioning tools */
static int virtblk_getgeo(struct block_device *bd, struct hd_geometry *geo)
{
struct virtio_blk *vblk = bd->bd_disk->private_data;
+ int ret = 0;
+
+ mutex_lock(&vblk->vdev_mutex);
+
+ if (!vblk->vdev) {
+ ret = -ENXIO;
+ goto out;
+ }
/* see if the host passed in geometry config */
if (virtio_has_feature(vblk->vdev, VIRTIO_BLK_F_GEOMETRY)) {
@@ -314,11 +375,15 @@
geo->sectors = 1 << 5;
geo->cylinders = get_capacity(bd->bd_disk) >> 11;
}
- return 0;
+out:
+ mutex_unlock(&vblk->vdev_mutex);
+ return ret;
}
static const struct block_device_operations virtblk_fops = {
.owner = THIS_MODULE,
+ .open = virtblk_open,
+ .release = virtblk_release,
.getgeo = virtblk_getgeo,
};
@@ -655,6 +720,10 @@
goto out_free_index;
}
+ /* This reference is dropped in virtblk_remove(). */
+ refcount_set(&vblk->refs, 1);
+ mutex_init(&vblk->vdev_mutex);
+
vblk->vdev = vdev;
vblk->sg_elems = sg_elems;
@@ -820,8 +889,6 @@
static void virtblk_remove(struct virtio_device *vdev)
{
struct virtio_blk *vblk = vdev->priv;
- int index = vblk->index;
- int refc;
/* Make sure no work handler is accessing the device. */
flush_work(&vblk->config_work);
@@ -831,18 +898,21 @@
blk_mq_free_tag_set(&vblk->tag_set);
+ mutex_lock(&vblk->vdev_mutex);
+
/* Stop all the virtqueues. */
vdev->config->reset(vdev);
- refc = kref_read(&disk_to_dev(vblk->disk)->kobj.kref);
+ /* Virtqueues are stopped, nothing can use vblk->vdev anymore. */
+ vblk->vdev = NULL;
+
put_disk(vblk->disk);
vdev->config->del_vqs(vdev);
kfree(vblk->vqs);
- kfree(vblk);
- /* Only free device id if we don't have any users */
- if (refc == 1)
- ida_simple_remove(&vd_index_ida, index);
+ mutex_unlock(&vblk->vdev_mutex);
+
+ virtblk_put(vblk);
}
#ifdef CONFIG_PM_SLEEP
diff --git a/drivers/vhost/vsock.c b/drivers/vhost/vsock.c
index e36aaf9..0716a9c 100644
--- a/drivers/vhost/vsock.c
+++ b/drivers/vhost/vsock.c
@@ -543,6 +543,11 @@
mutex_unlock(&vq->mutex);
}
+ /* Some packets may have been queued before the device was started,
+ * let's kick the send worker to send them.
+ */
+ vhost_work_queue(&vsock->dev, &vsock->send_pkt_work);
+
mutex_unlock(&vsock->dev.mutex);
return 0;
