rte_virtio: remove vtpci_internal

Now that legacy PCI support has
been dropped, we can safely assume
there's only one backend type
per device. So the vtpci_internal
- containing process-local data -
can be removed.

Change-Id: I15d87a280b74318c7a44ee60ce3408756d1f5a69
Signed-off-by: Dariusz Stojaczyk <dariuszx.stojaczyk@intel.com>
Reviewed-on: https://review.gerrithub.io/385423
Reviewed-by: Daniel Verkamp <daniel.verkamp@intel.com>
Tested-by: SPDK Automated Test System <sys_sgsw@intel.com>
Reviewed-by: Jim Harris <james.r.harris@intel.com>

lib/bdev/virtio/rte_virtio/virtio_dev.c

@@ -287,11 +287,8 @@ virtio_dev_init(struct virtio_dev *dev, uint64_t req_features)
 void
 virtio_dev_free(struct virtio_dev *dev)
 {
-	uint32_t vdev_id = dev->id;
-
 	virtio_free_queues(dev);
 	vtpci_ops(dev)->free_vdev(dev);
-	vtpci_deinit(vdev_id);
 	pthread_mutex_destroy(&dev->mutex);
 	free(dev);
 }

lib/bdev/virtio/rte_virtio/virtio_dev.h

@@ -98,6 +98,9 @@ struct virtio_dev {
 	/** Mutex for asynchronous virtqueue-changing operations. */
 	pthread_mutex_t	mutex;
 
+	/** Backend-specific callbacks. */
+	const struct virtio_pci_ops *backend_ops;
+
 	/** Context for the backend ops */
 	void		*ctx;
 

lib/bdev/virtio/rte_virtio/virtio_pci.c

@@ -43,6 +43,7 @@
 struct virtio_driver g_virtio_driver = {
 	.init_ctrlrs = TAILQ_HEAD_INITIALIZER(g_virtio_driver.init_ctrlrs),
 	.attached_ctrlrs = TAILQ_HEAD_INITIALIZER(g_virtio_driver.attached_ctrlrs),
+	.ctrlr_counter = 0,
 };
 
 /*
@@ -519,27 +520,17 @@ struct virtio_dev *
 	struct virtio_dev *vdev;
 	unsigned vdev_num;
 
-	for (vdev_num = 0; vdev_num < VIRTIO_MAX_DEVICES; vdev_num++) {
-		if (g_virtio_driver.internal[vdev_num].vtpci_ops == NULL) {
-			break;
-		}
-	}
-
-	if (vdev_num == VIRTIO_MAX_DEVICES) {
-		SPDK_ERRLOG("Max vhost device limit reached (%u).\n", VIRTIO_MAX_DEVICES);
-		return NULL;
-	}
-
 	vdev = calloc(1, sizeof(*vdev));
 	if (vdev == NULL) {
 		SPDK_ERRLOG("virtio device calloc failed\n");
 		return NULL;
 	}
 
+	vdev_num = __sync_add_and_fetch(&g_virtio_driver.ctrlr_counter, 1);
 	vdev->id = vdev_num;
 	pthread_mutex_init(&vdev->mutex, NULL);
+	vdev->backend_ops = ops;
 	vdev->ctx = ctx;
-	g_virtio_driver.internal[vdev_num].vtpci_ops = ops;
 
 	return vdev;
 }
@@ -558,13 +549,7 @@ vtpci_enumerate_pci(void)
 const struct virtio_pci_ops *
 vtpci_ops(struct virtio_dev *dev)
 {
-	return g_virtio_driver.internal[dev->id].vtpci_ops;
+	return dev->backend_ops;
-}
-
-void
-vtpci_deinit(uint32_t id)
-{
-	g_virtio_driver.internal[id].vtpci_ops = NULL;
 }
 
 void

lib/bdev/virtio/rte_virtio/virtio_pci.h

@@ -45,8 +45,6 @@
 
 struct virtqueue;
 
-#define VIRTIO_MAX_DEVICES 128
-
 /* Extra status define for readability */
 #define VIRTIO_CONFIG_S_RESET 0
 
@@ -104,19 +102,12 @@ struct virtio_hw {
 	struct virtio_scsi_config *dev_cfg;
 };
 
-/*
- * While virtio_hw is stored in shared memory, this structure stores
- * some infos that may vary in the multiple process model locally.
- * For example, the vtpci_ops pointer.
- */
-struct vtpci_internal {
-	const struct virtio_pci_ops *vtpci_ops;
-};
-
 struct virtio_driver {
-	struct vtpci_internal internal[VIRTIO_MAX_DEVICES];
 	TAILQ_HEAD(, virtio_dev) init_ctrlrs;
 	TAILQ_HEAD(, virtio_dev) attached_ctrlrs;
+
+	/* Increment-only virtio_dev counter */
+	unsigned ctrlr_counter;
 };
 
 extern struct virtio_driver g_virtio_driver;
@@ -145,8 +136,6 @@ void vtpci_read_dev_config(struct virtio_dev *, size_t, void *, int);
 
 const struct virtio_pci_ops *vtpci_ops(struct virtio_dev *dev);
 
-void vtpci_deinit(uint32_t id);
-
 void vtpci_dump_json_config(struct virtio_dev *hw, struct spdk_json_write_ctx *w);
 
 extern const struct virtio_pci_ops virtio_user_ops;