Commit 1f20593b authored by Ben Walker's avatar Ben Walker Committed by Darek Stojaczyk
Browse files

nbd: Wait for kernel module to become ready on start up 



The ioctl NBD_SET_SOCK can return EBUSY if the kernel module
hasn't loaded entirely yet. Wait for it to become ready.

Change-Id: If3c6d0d8bb678ef8cab0efc1c5e800e95e19133e
Signed-off-by: default avatarBen Walker <benjamin.walker@intel.com>
Reviewed-on: https://review.gerrithub.io/433939


Chandler-Test-Pool: SPDK Automated Test System <sys_sgsw@intel.com>
Tested-by: default avatarSPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: default avatarDarek Stojaczyk <dariusz.stojaczyk@intel.com>
Reviewed-by: default avatarJim Harris <james.r.harris@intel.com>
parent bb005da5

lib/nbd/nbd.c

+43 −8
Original line number Diff line number Diff line
@@ -841,6 +841,7 @@ struct spdk_nbd_start_ctx { 
	struct spdk_nbd_disk	*nbd;

	spdk_nbd_start_cb	cb_fn;

	void			*cb_arg;

	struct spdk_poller	*poller;

};



static void
@@ -896,6 +897,47 @@ err: 
	free(ctx);

}



static int

spdk_nbd_enable_kernel(void *arg)

{

	struct spdk_nbd_start_ctx *ctx = arg;

	int rc;



	rc = ioctl(ctx->nbd->dev_fd, NBD_SET_SOCK, ctx->nbd->kernel_sp_fd);

	if (rc == -1) {

		if (errno == EBUSY) {

			if (ctx->poller == NULL) {

				ctx->poller = spdk_poller_register(spdk_nbd_enable_kernel, ctx, 20000);

			}

			/* If the kernel is busy, check back later */

			return 0;

		}





		SPDK_ERRLOG("ioctl(NBD_SET_SOCK) failed: %s\n", spdk_strerror(errno));

		if (ctx->poller) {

			spdk_poller_unregister(&ctx->poller);

		}



		spdk_nbd_stop(ctx->nbd);



		if (ctx->cb_fn) {

			ctx->cb_fn(ctx->cb_arg, NULL, -errno);

		}



		free(ctx);

		return 1;

	}



	if (ctx->poller) {

		spdk_poller_unregister(&ctx->poller);

	}



	spdk_nbd_start_complete(ctx);



	return 1;

}



void

spdk_nbd_start(const char *bdev_name, const char *nbd_path,

	       spdk_nbd_start_cb cb_fn, void *cb_arg)
@@ -999,14 +1041,7 @@ spdk_nbd_start(const char *bdev_name, const char *nbd_path, 
	SPDK_INFOLOG(SPDK_LOG_NBD, "Enabling kernel access to bdev %s via %s\n",

		     spdk_bdev_get_name(bdev), nbd_path);



	rc = ioctl(nbd->dev_fd, NBD_SET_SOCK, nbd->kernel_sp_fd);

	if (rc == -1) {

		SPDK_ERRLOG("ioctl(NBD_SET_SOCK) failed: %s\n", spdk_strerror(errno));

		rc = -errno;

		goto err;

	}



	spdk_nbd_start_complete(ctx);

	spdk_nbd_enable_kernel(ctx);

	return;



err: