[SCSI] virtio-scsi: Add vdrv->scan for post VIRTIO_CONFIG_S_DRIVER_OK…

… LUN scanning This patch changes virtio-scsi to use a new virtio_driver->scan() callback so that scsi_scan_host() can be properly invoked once virtio_dev_probe() has set add_status(dev, VIRTIO_CONFIG_S_DRIVER_OK) to signal active virtio-ring operation, instead of from within virtscsi_probe(). This fixes a bug where SCSI LUN scanning for both virtio-scsi-raw and virtio-scsi/tcm_vhost setups was happening before VIRTIO_CONFIG_S_DRIVER_OK had been set, causing VIRTIO_SCSI_S_BAD_TARGET to occur. This fixes a bug with virtio-scsi/tcm_vhost where LUN scan was not detecting LUNs. Tested with virtio-scsi-raw + virtio-scsi/tcm_vhost w/ IBLOCK on 3.5-rc2 code. Signed-off-by: Nicholas Bellinger <[email protected]> Acked-by: Paolo Bonzini <[email protected]> Signed-off-by: James Bottomley <[email protected]>
jadonk · Jul 20, 2012 · 59057fb · 59057fb
1 parent 0b1017a
commit 59057fb
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Showing 3 changed files with 17 additions and 4 deletions.
diff --git a/drivers/scsi/virtio_scsi.c b/drivers/scsi/virtio_scsi.c
@@ -571,6 +571,13 @@ static struct virtio_scsi_target_state *virtscsi_alloc_tgt(
 	return tgt;
 }
 
+static void virtscsi_scan(struct virtio_device *vdev)
+{
+	struct Scsi_Host *shost = (struct Scsi_Host *)vdev->priv;
+
+	scsi_scan_host(shost);
+}
+
 static void virtscsi_remove_vqs(struct virtio_device *vdev)
 {
 	struct Scsi_Host *sh = virtio_scsi_host(vdev);
@@ -677,9 +684,10 @@ static int __devinit virtscsi_probe(struct virtio_device *vdev)
 	err = scsi_add_host(shost, &vdev->dev);
 	if (err)
 		goto scsi_add_host_failed;
-
-	scsi_scan_host(shost);
-
+	/*
+	 * scsi_scan_host() happens in virtscsi_scan() via virtio_driver->scan()
+	 * after VIRTIO_CONFIG_S_DRIVER_OK has been set..
+	 */
 	return 0;
 
 scsi_add_host_failed:
@@ -735,6 +743,7 @@ static struct virtio_driver virtio_scsi_driver = {
 	.driver.owner = THIS_MODULE,
 	.id_table = id_table,
 	.probe = virtscsi_probe,
+	.scan = virtscsi_scan,
 #ifdef CONFIG_PM
 	.freeze = virtscsi_freeze,
 	.restore = virtscsi_restore,

diff --git a/drivers/virtio/virtio.c b/drivers/virtio/virtio.c
@@ -141,8 +141,11 @@ static int virtio_dev_probe(struct device *_d)
 	err = drv->probe(dev);
 	if (err)
 		add_status(dev, VIRTIO_CONFIG_S_FAILED);
-	else
+	else {
 		add_status(dev, VIRTIO_CONFIG_S_DRIVER_OK);
+		if (drv->scan)
+			drv->scan(dev);
+	}
 
 	return err;
 }

diff --git a/include/linux/virtio.h b/include/linux/virtio.h
@@ -92,6 +92,7 @@ struct virtio_driver {
 	const unsigned int *feature_table;
 	unsigned int feature_table_size;
 	int (*probe)(struct virtio_device *dev);
+	void (*scan)(struct virtio_device *dev);
 	void (*remove)(struct virtio_device *dev);
 	void (*config_changed)(struct virtio_device *dev);
 #ifdef CONFIG_PM