Commit 46bce34c authored by Dariusz Stojaczyk's avatar Dariusz Stojaczyk Committed by Jim Harris
Browse files

bdev/virtio: ensure thread safety for adding/removing devices 



Also, device removal is now always deferred to simplify
the locking.

Change-Id: I6b994531630b64860da728a93a0f2d613d8aa5ba
Signed-off-by: default avatarDariusz Stojaczyk <dariuszx.stojaczyk@intel.com>
Reviewed-on: https://review.gerrithub.io/405181


Tested-by: default avatarSPDK Automated Test System <sys_sgsw@intel.com>
Reviewed-by: default avatarShuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>
Reviewed-by: default avatarDaniel Verkamp <daniel.verkamp@intel.com>
parent 20acc18b

lib/bdev/virtio/bdev_virtio_scsi.c

+36 −14
Original line number Diff line number Diff line
@@ -184,6 +184,8 @@ struct bdev_virtio_io_channel { 
TAILQ_HEAD(, virtio_scsi_dev) g_virtio_scsi_devs =

	TAILQ_HEAD_INITIALIZER(g_virtio_scsi_devs);



pthread_mutex_t g_virtio_scsi_mutex = PTHREAD_MUTEX_INITIALIZER;



/** Module finish in progress */

static bool g_bdev_virtio_finish = false;
@@ -293,7 +295,9 @@ virtio_scsi_dev_init(struct virtio_scsi_dev *svdev, uint16_t max_queues) 
				bdev_virtio_scsi_ch_destroy_cb,

				sizeof(struct bdev_virtio_io_channel));



	pthread_mutex_lock(&g_virtio_scsi_mutex);

	TAILQ_INSERT_TAIL(&g_virtio_scsi_devs, svdev, tailq);

	pthread_mutex_unlock(&g_virtio_scsi_mutex);

	return 0;

}
@@ -1687,13 +1691,16 @@ bdev_virtio_initial_scan_complete(void *ctx __attribute__((unused)), 
{

	struct virtio_scsi_dev *svdev;



	pthread_mutex_lock(&g_virtio_scsi_mutex);

	TAILQ_FOREACH(svdev, &g_virtio_scsi_devs, tailq) {

		if (svdev->scan_ctx) {

			/* another device is still being scanned */

			pthread_mutex_unlock(&g_virtio_scsi_mutex);

			return;

		}

	}



	pthread_mutex_unlock(&g_virtio_scsi_mutex);

	spdk_bdev_module_init_done(&virtio_scsi_if);

}
@@ -1704,52 +1711,48 @@ bdev_virtio_initialize(void) 
	int rc;



	rc = bdev_virtio_process_config();

	pthread_mutex_lock(&g_virtio_scsi_mutex);



	if (rc != 0) {

		goto out;

		goto err_unlock;

	}



	if (TAILQ_EMPTY(&g_virtio_scsi_devs)) {

		spdk_bdev_module_init_done(&virtio_scsi_if);

		return 0;

		goto out_unlock;

	}



	/* Initialize all created devices and scan available targets */

	TAILQ_FOREACH(svdev, &g_virtio_scsi_devs, tailq) {

		rc = virtio_scsi_dev_scan(svdev, bdev_virtio_initial_scan_complete, NULL);

		if (rc != 0) {

			goto out;

			goto err_unlock;

		}

	}



	pthread_mutex_unlock(&g_virtio_scsi_mutex);

	return 0;



out:

err_unlock:

	/* Remove any created devices */

	TAILQ_FOREACH_SAFE(svdev, &g_virtio_scsi_devs, tailq, next_svdev) {

		virtio_scsi_dev_remove(svdev, NULL, NULL);

	}



out_unlock:

	pthread_mutex_unlock(&g_virtio_scsi_mutex);

	spdk_bdev_module_init_done(&virtio_scsi_if);

	return rc;

}



static void

virtio_scsi_dev_unregister_cb(void *io_device)

_virtio_scsi_dev_unregister_cb(void *io_device)

{

	struct virtio_scsi_dev *svdev = io_device;

	struct virtio_dev *vdev = &svdev->vdev;

	struct spdk_thread *thread;

	bool finish_module;

	bdev_virtio_remove_cb remove_cb;

	void *remove_ctx;



	thread = virtio_dev_queue_get_thread(vdev, VIRTIO_SCSI_CONTROLQ);

	if (thread != spdk_get_thread()) {

		spdk_thread_send_msg(thread, virtio_scsi_dev_unregister_cb, io_device);

		return;

	}



	/* bdevs built on top of this vdev mustn't be destroyed with outstanding I/O. */

	assert(spdk_ring_count(svdev->ctrlq_ring) == 0);

	spdk_ring_free(svdev->ctrlq_ring);

	spdk_poller_unregister(&svdev->mgmt_poller);
@@ -1760,7 +1763,10 @@ virtio_scsi_dev_unregister_cb(void *io_device) 
	virtio_dev_stop(vdev);

	virtio_dev_destruct(vdev);



	pthread_mutex_lock(&g_virtio_scsi_mutex);

	TAILQ_REMOVE(&g_virtio_scsi_devs, svdev, tailq);

	pthread_mutex_unlock(&g_virtio_scsi_mutex);



	remove_cb = svdev->remove_cb;

	remove_ctx = svdev->remove_ctx;

	spdk_dma_free(svdev->eventq_ios);
@@ -1777,6 +1783,16 @@ virtio_scsi_dev_unregister_cb(void *io_device) 
	}

}



static void

virtio_scsi_dev_unregister_cb(void *io_device)

{

	struct virtio_scsi_dev *svdev = io_device;

	struct spdk_thread *thread;



	thread = virtio_dev_queue_get_thread(&svdev->vdev, VIRTIO_SCSI_CONTROLQ);

	spdk_thread_send_msg(thread, _virtio_scsi_dev_unregister_cb, io_device);

}



static void

virtio_scsi_dev_remove(struct virtio_scsi_dev *svdev,

		       bdev_virtio_remove_cb cb_fn, void *cb_arg)
@@ -1819,7 +1835,9 @@ bdev_virtio_finish(void) 


	g_bdev_virtio_finish = true;



	pthread_mutex_lock(&g_virtio_scsi_mutex);

	if (TAILQ_EMPTY(&g_virtio_scsi_devs)) {

		pthread_mutex_unlock(&g_virtio_scsi_mutex);

		spdk_bdev_module_finish_done();

		return;

	}
@@ -1828,6 +1846,7 @@ bdev_virtio_finish(void) 
	TAILQ_FOREACH_SAFE(svdev, &g_virtio_scsi_devs, tailq, next) {

		virtio_scsi_dev_remove(svdev, NULL, NULL);

	}

	pthread_mutex_unlock(&g_virtio_scsi_mutex);

}



int
@@ -1896,6 +1915,7 @@ bdev_virtio_scsi_dev_remove(const char *name, bdev_virtio_remove_cb cb_fn, void 
{

	struct virtio_scsi_dev *svdev;



	pthread_mutex_lock(&g_virtio_scsi_mutex);

	TAILQ_FOREACH(svdev, &g_virtio_scsi_devs, tailq) {

		if (strcmp(svdev->vdev.name, name) == 0) {

			break;
@@ -1903,12 +1923,14 @@ bdev_virtio_scsi_dev_remove(const char *name, bdev_virtio_remove_cb cb_fn, void 
	}



	if (svdev == NULL) {

		pthread_mutex_unlock(&g_virtio_scsi_mutex);

		SPDK_ERRLOG("Cannot find Virtio-SCSI device named '%s'\n", name);

		cb_fn(cb_arg, -ENODEV);

		return;

	}



	virtio_scsi_dev_remove(svdev, cb_fn, cb_arg);

	pthread_mutex_unlock(&g_virtio_scsi_mutex);

}



SPDK_LOG_REGISTER_COMPONENT("virtio", SPDK_LOG_VIRTIO)