lib/nvme: add NVMe character device

NVMe character device implementation. This patch adds implementation
of IO producer using CUSE library. It allows to create nvme device
nodes in linux kernel for controller as well as for namespace and
process ioctl requests as usual from linux environment.

Both devices (controller and namespaces) are exposed as character
devices.

To compile NVMe CUSE module use "./configure --with-nvme-cuse".

Names for created CUSE devices can be retrieved using
spdk_nvme_cuse_get_ctrlr_name() and spdk_nvme_cuse_get_ns_name().


Signed-off-by: Jim Harris <james.r.harris@intel.com>
Signed-off-by: Tomasz Kulasek <tomaszx.kulasek@intel.com>
Signed-off-by: Tomasz Zawadzki <tomasz.zawadzki@intel.com>
Signed-off-by: Maciej Szwed <maciej.szwed@intel.com>
Change-Id: I0fc9a9a1ef3c9c2b3112d07c2b4b1f8d49665ee1
Reviewed-on: https://review.gerrithub.io/c/spdk/spdk/+/466917
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>

CONFIG

@@ -94,6 +94,9 @@ CONFIG_FIO_SOURCE_DIR=/usr/src/fio
 CONFIG_RDMA=n
 CONFIG_RDMA_SEND_WITH_INVAL=n
 
+# Enable NVMe Character Devices.
+CONFIG_NVME_CUSE=n
+
 # Enable FC support for the NVMf target.
 # Requires FC low level driver (from FC vendor)
 CONFIG_FC=n

configure

@@ -94,6 +94,8 @@ function usage()
 	echo "                           be searched."
 	echo " fuse                      Build FUSE components for mounting a blobfs filesystem."
 	echo "                           No path required."
+	echo " nvme-cuse                 Build NVMe driver with support for CUSE-based character devices."
+	echo "                           No path required."
 	echo ""
 	echo "Environment variables:"
 	echo ""
@@ -363,6 +365,12 @@ for i in "$@"; do
 		--without-fuse)
 			CONFIG[FUSE]=n
 			;;
+		--with-nvme-cuse)
+			CONFIG[NVME_CUSE]=y
+			;;
+		--without-nvme-cuse)
+			CONFIG[NVME_CUSE]=n
+			;;
 		--)
 			break
 			;;
@@ -611,6 +619,15 @@ if [[ "${CONFIG[VPP]}" = "y" ]]; then
 	fi
 fi
 
+if [[ "${CONFIG[NVME_CUSE]}" = "y" ]]; then
+	if ! echo -e '#define FUSE_USE_VERSION 31\n#include <fuse3/cuse_lowlevel.h>\n#include <fuse3/fuse_lowlevel.h>\n#include <fuse3/fuse_opt.h>\nint main(void) { return 0; }\n' \
+		| ${BUILD_CMD[@]} -lfuse3 -D_FILE_OFFSET_BITS=64 - 2>/dev/null; then
+		echo --with-cuse requires libfuse3.
+		echo Please install then re-run this script.
+		exit 1
+	fi
+fi
+
 if [[ "${CONFIG[RBD]}" = "y" ]]; then
 	if ! echo -e '#include <rbd/librbd.h>\n#include <rados/librados.h>\n' \
 		'int main(void) { return 0; }\n' \

include/spdk/nvme.h

@@ -2584,6 +2584,25 @@ struct spdk_nvme_rdma_hooks {
  */
 void spdk_nvme_rdma_init_hooks(struct spdk_nvme_rdma_hooks *hooks);
 
+/**
+ * Get name of cuse device associated with NVMe controller.
+ *
+ * \param ctrlr Opaque handle to NVMe controller.
+ *
+ * \return Pointer to the name of device.
+ */
+char *spdk_nvme_cuse_get_ctrlr_name(struct spdk_nvme_ctrlr *ctrlr);
+
+/**
+ * Get name of cuse device associated with NVMe namespace.
+ *
+ * \param ctrlr Opaque handle to NVMe controller.
+ * \param nsid Namespace id.
+ *
+ * \return Pointer to the name of device.
+ */
+char *spdk_nvme_cuse_get_ns_name(struct spdk_nvme_ctrlr *ctrlr, uint32_t nsid);
+
 #ifdef __cplusplus
 }
 #endif

lib/nvme/Makefile

@@ -37,6 +37,8 @@ include $(SPDK_ROOT_DIR)/mk/spdk.common.mk
 C_SRCS = nvme_ctrlr_cmd.c nvme_ctrlr.c nvme_fabric.c nvme_ns_cmd.c nvme_ns.c nvme_pcie.c nvme_qpair.c nvme.c nvme_quirks.c nvme_transport.c nvme_uevent.c nvme_ctrlr_ocssd_cmd.c \
 	nvme_ns_ocssd_cmd.c nvme_tcp.c nvme_opal.c nvme_io_msg.c
 C_SRCS-$(CONFIG_RDMA) += nvme_rdma.c
+C_SRCS-$(CONFIG_NVME_CUSE) += nvme_cuse.c
+
 LIBNAME = nvme
 LOCAL_SYS_LIBS = -luuid
 ifeq ($(CONFIG_RDMA),y)
@@ -58,4 +60,9 @@ endif
 endif
 endif
 
+ifeq ($(CONFIG_NVME_CUSE),y)
+# fuse requires to set _FILE_OFFSET_BITS to 64 bits even for 64 bit machines
+CFLAGS += -D_FILE_OFFSET_BITS=64
+endif
+
 include $(SPDK_ROOT_DIR)/mk/spdk.lib.mk

lib/nvme/nvme_cuse.c

@@ -0,0 +1,349 @@
+/*-
+ *   BSD LICENSE
+ *
+ *   Copyright (c) Intel Corporation.
+ *   All rights reserved.
+ *
+ *   Redistribution and use in source and binary forms, with or without
+ *   modification, are permitted provided that the following conditions
+ *   are met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in
+ *       the documentation and/or other materials provided with the
+ *       distribution.
+ *     * Neither the name of Intel Corporation nor the names of its
+ *       contributors may be used to endorse or promote products derived
+ *       from this software without specific prior written permission.
+ *
+ *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#define FUSE_USE_VERSION 31
+
+#include <fuse3/cuse_lowlevel.h>
+
+#include <linux/nvme_ioctl.h>
+#include <linux/fs.h>
+
+#include "nvme_internal.h"
+#include "nvme_io_msg.h"
+#include "nvme_cuse.h"
+
+struct cuse_device {
+	char				dev_name[128];
+
+	struct spdk_nvme_ctrlr		*ctrlr;		/**< NVMe controller */
+	uint32_t			nsid;		/**< NVMe name space id, or 0 */
+
+	uint32_t			idx;
+	pthread_t			tid;
+	struct fuse_session		*session;
+
+	struct cuse_device		*ctrlr_device;
+	TAILQ_HEAD(, cuse_device)	ns_devices;
+
+	TAILQ_ENTRY(cuse_device)	tailq;
+};
+
+static TAILQ_HEAD(, cuse_device) g_ctrlr_ctx_head = TAILQ_HEAD_INITIALIZER(g_ctrlr_ctx_head);
+static int g_controllers_found = 0;
+
+static void
+cuse_ctrlr_ioctl(fuse_req_t req, int cmd, void *arg,
+		 struct fuse_file_info *fi, unsigned flags,
+		 const void *in_buf, size_t in_bufsz, size_t out_bufsz)
+{
+	if (flags & FUSE_IOCTL_COMPAT) {
+		fuse_reply_err(req, ENOSYS);
+		return;
+	}
+
+	SPDK_ERRLOG("Unsupported IOCTL 0x%X.\n", cmd);
+	fuse_reply_err(req, EINVAL);
+}
+
+static void
+cuse_ns_ioctl(fuse_req_t req, int cmd, void *arg,
+	      struct fuse_file_info *fi, unsigned flags,
+	      const void *in_buf, size_t in_bufsz, size_t out_bufsz)
+{
+	if (flags & FUSE_IOCTL_COMPAT) {
+		fuse_reply_err(req, ENOSYS);
+		return;
+	}
+
+	SPDK_ERRLOG("Unsupported IOCTL 0x%X.\n", cmd);
+	fuse_reply_err(req, EINVAL);
+}
+
+/*****************************************************************************
+ * CUSE threads initialization.
+ */
+
+static void cuse_open(fuse_req_t req, struct fuse_file_info *fi)
+{
+	fuse_reply_open(req, fi);
+}
+
+static const struct cuse_lowlevel_ops cuse_ctrlr_clop = {
+	.open		= cuse_open,
+	.ioctl		= cuse_ctrlr_ioctl,
+};
+
+static const struct cuse_lowlevel_ops cuse_ns_clop = {
+	.open		= cuse_open,
+	.ioctl		= cuse_ns_ioctl,
+};
+
+static void *
+cuse_thread(void *arg)
+{
+	struct cuse_device *cuse_device = arg;
+	char *cuse_argv[] = { "cuse", "-f" };
+	int cuse_argc = SPDK_COUNTOF(cuse_argv);
+	char devname_arg[128 + 8];
+	const char *dev_info_argv[] = { devname_arg };
+	struct cuse_info ci;
+	int multithreaded;
+
+	spdk_unaffinitize_thread();
+
+	snprintf(devname_arg, sizeof(devname_arg), "DEVNAME=%s", cuse_device->dev_name);
+
+	memset(&ci, 0, sizeof(ci));
+	ci.dev_info_argc = 1;
+	ci.dev_info_argv = dev_info_argv;
+	ci.flags = CUSE_UNRESTRICTED_IOCTL;
+
+	if (cuse_device->nsid) {
+		cuse_device->session = cuse_lowlevel_setup(cuse_argc, cuse_argv, &ci, &cuse_ns_clop,
+				       &multithreaded, cuse_device);
+	} else {
+		cuse_device->session = cuse_lowlevel_setup(cuse_argc, cuse_argv, &ci, &cuse_ctrlr_clop,
+				       &multithreaded, cuse_device);
+	}
+	if (!cuse_device->session) {
+		SPDK_ERRLOG("Cannot create cuse session\n");
+		goto end;
+	}
+
+	SPDK_NOTICELOG("fuse session for device %s created\n", cuse_device->dev_name);
+	fuse_session_loop(cuse_device->session);
+
+end:
+	cuse_lowlevel_teardown(cuse_device->session);
+	pthread_exit(NULL);
+}
+
+/*****************************************************************************
+ * CUSE devices management
+ */
+
+static int
+cuse_nvme_ns_start(struct cuse_device *ctrlr_device, uint32_t nsid)
+{
+	struct cuse_device *ns_device;
+
+	ns_device = (struct cuse_device *)calloc(1, sizeof(struct cuse_device));
+	if (!ns_device) {
+		SPDK_ERRLOG("Cannot allocate momeory for ns_device.");
+		return -ENOMEM;
+	}
+
+	ns_device->ctrlr = ctrlr_device->ctrlr;
+	ns_device->ctrlr_device = ctrlr_device;
+	ns_device->idx = nsid;
+	ns_device->nsid = nsid;
+	snprintf(ns_device->dev_name, sizeof(ns_device->dev_name), "spdk/nvme%dn%d",
+		 ctrlr_device->idx, ns_device->idx);
+
+	if (pthread_create(&ns_device->tid, NULL, cuse_thread, ns_device)) {
+		SPDK_ERRLOG("pthread_create failed\n");
+		free(ns_device);
+		return -1;
+	}
+
+	TAILQ_INSERT_TAIL(&ctrlr_device->ns_devices, ns_device, tailq);
+	return 0;
+}
+
+static void
+cuse_nvme_ctrlr_stop(struct cuse_device *ctrlr_device)
+{
+	struct cuse_device *ns_device, *tmp;
+
+	TAILQ_FOREACH_SAFE(ns_device, &ctrlr_device->ns_devices, tailq, tmp) {
+		fuse_session_exit(ns_device->session);
+		pthread_kill(ns_device->tid, SIGHUP);
+		pthread_join(ns_device->tid, NULL);
+		TAILQ_REMOVE(&ctrlr_device->ns_devices, ns_device, tailq);
+		free(ns_device);
+	}
+
+	fuse_session_exit(ctrlr_device->session);
+	pthread_kill(ctrlr_device->tid, SIGHUP);
+	pthread_join(ctrlr_device->tid, NULL);
+	TAILQ_REMOVE(&g_ctrlr_ctx_head, ctrlr_device, tailq);
+	free(ctrlr_device);
+}
+
+static int
+nvme_cuse_start(struct spdk_nvme_ctrlr *ctrlr)
+{
+	uint32_t i, nsid;
+	struct cuse_device *ctrlr_device;
+
+	SPDK_NOTICELOG("Creating cuse device for controller\n");
+
+	ctrlr_device = (struct cuse_device *)calloc(1, sizeof(struct cuse_device));
+	if (!ctrlr_device) {
+		SPDK_ERRLOG("Cannot allocate memory for ctrlr_device.");
+		return -ENOMEM;
+	}
+
+	TAILQ_INIT(&ctrlr_device->ns_devices);
+	ctrlr_device->ctrlr = ctrlr;
+	ctrlr_device->idx = g_controllers_found++;
+	snprintf(ctrlr_device->dev_name, sizeof(ctrlr_device->dev_name),
+		 "spdk/nvme%d", ctrlr_device->idx);
+
+	if (pthread_create(&ctrlr_device->tid, NULL, cuse_thread, ctrlr_device)) {
+		SPDK_ERRLOG("pthread_create failed\n");
+		free(ctrlr_device);
+		return -1;
+	}
+	TAILQ_INSERT_TAIL(&g_ctrlr_ctx_head, ctrlr_device, tailq);
+
+	/* Start all active namespaces */
+	for (i = 0; i < spdk_nvme_ctrlr_get_num_ns(ctrlr); i++) {
+		nsid = i + 1;
+		if (!spdk_nvme_ctrlr_is_active_ns(ctrlr, nsid)) {
+			continue;
+		}
+
+		if (cuse_nvme_ns_start(ctrlr_device, nsid) < 0) {
+			SPDK_ERRLOG("Cannot start CUSE namespace device.");
+			cuse_nvme_ctrlr_stop(ctrlr_device);
+			return -1;
+		}
+	}
+
+	return 0;
+}
+
+static void
+nvme_cuse_stop(struct spdk_nvme_ctrlr *ctrlr)
+{
+	struct cuse_device *ctrlr_device;
+
+	TAILQ_FOREACH(ctrlr_device, &g_ctrlr_ctx_head, tailq) {
+		if (ctrlr_device->ctrlr == ctrlr) {
+			break;
+		}
+	}
+
+	if (!ctrlr_device) {
+		SPDK_ERRLOG("Cannot find associated CUSE device\n");
+		return;
+	}
+
+	cuse_nvme_ctrlr_stop(ctrlr_device);
+}
+
+static struct nvme_io_msg_producer cuse_nvme_io_msg_producer = {
+	.name = "cuse",
+};
+
+int
+nvme_cuse_register(struct spdk_nvme_ctrlr *ctrlr)
+{
+	int rc;
+
+	rc = nvme_io_msg_ctrlr_start(ctrlr, &cuse_nvme_io_msg_producer);
+	if (rc) {
+		return rc;
+	}
+
+	rc = nvme_cuse_start(ctrlr);
+	if (rc) {
+		nvme_io_msg_ctrlr_stop(ctrlr, &cuse_nvme_io_msg_producer, false);
+	}
+
+	return rc;
+}
+
+void
+nvme_cuse_unregister(struct spdk_nvme_ctrlr *ctrlr)
+{
+	nvme_cuse_stop(ctrlr);
+
+	nvme_io_msg_ctrlr_stop(ctrlr, &cuse_nvme_io_msg_producer, false);
+}
+
+char *
+spdk_nvme_cuse_get_ctrlr_name(struct spdk_nvme_ctrlr *ctrlr)
+{
+	struct cuse_device *ctrlr_device;
+
+	if (TAILQ_EMPTY(&g_ctrlr_ctx_head)) {
+		return NULL;
+	}
+
+	TAILQ_FOREACH(ctrlr_device, &g_ctrlr_ctx_head, tailq) {
+		if (ctrlr_device->ctrlr == ctrlr) {
+			break;
+		}
+	}
+
+	if (!ctrlr_device) {
+		return NULL;
+	}
+
+	return ctrlr_device->dev_name;
+}
+
+char *
+spdk_nvme_cuse_get_ns_name(struct spdk_nvme_ctrlr *ctrlr, uint32_t nsid)
+{
+	struct cuse_device *ns_device;
+	struct cuse_device *ctrlr_device;
+
+	if (TAILQ_EMPTY(&g_ctrlr_ctx_head)) {
+		return NULL;
+	}
+
+	TAILQ_FOREACH(ctrlr_device, &g_ctrlr_ctx_head, tailq) {
+		if (ctrlr_device->ctrlr == ctrlr) {
+			break;
+		}
+	}
+
+	if (!ctrlr_device) {
+		return NULL;
+	}
+
+	TAILQ_FOREACH(ns_device, &ctrlr_device->ns_devices, tailq) {
+		if (ns_device->nsid == nsid) {
+			break;
+		}
+	}
+
+	if (!ns_device) {
+		return NULL;
+	}
+
+	return ns_device->dev_name;
+}

lib/nvme/nvme_cuse.h

@@ -0,0 +1,42 @@
+/*-
+ *   BSD LICENSE
+ *
+ *   Copyright (c) Intel Corporation.
+ *   All rights reserved.
+ *
+ *   Redistribution and use in source and binary forms, with or without
+ *   modification, are permitted provided that the following conditions
+ *   are met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in
+ *       the documentation and/or other materials provided with the
+ *       distribution.
+ *     * Neither the name of Intel Corporation nor the names of its
+ *       contributors may be used to endorse or promote products derived
+ *       from this software without specific prior written permission.
+ *
+ *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef __NVME_CUSE_H__
+#define __NVME_CUSE_H__
+
+#include "spdk/nvme.h"
+
+int nvme_cuse_register(struct spdk_nvme_ctrlr *ctrlr);
+void nvme_cuse_unregister(struct spdk_nvme_ctrlr *ctrlr);
+
+#endif /* __NVME_CUSE_H__ */

mk/spdk.common.mk

@@ -225,6 +225,10 @@ ifeq ($(CONFIG_LOG_BACKTRACE),y)
 SYS_LIBS += -lunwind
 endif
 
+ifeq ($(CONFIG_NVME_CUSE),y)
+SYS_LIBS += -lfuse3
+endif
+
 MAKEFLAGS += --no-print-directory
 
 C_SRCS += $(C_SRCS-y)

scripts/pkgdep.sh

@@ -73,6 +73,8 @@ if [ -s /etc/redhat-release ]; then
 	fi
 	# Additional dependencies for ISA-L used in compression
 	yum install -y autoconf automake libtool help2man
+	# Additional dependencies for FUSE and CUSE
+	yum install -y fuse3-devel
 elif [ -f /etc/debian_version ]; then
 	# Includes Ubuntu, Debian
 	apt-get install -y gcc g++ make libcunit1-dev libaio-dev libssl-dev \
@@ -93,6 +95,8 @@ elif [ -f /etc/debian_version ]; then
 		"Note: Some SPDK CLI dependencies could not be installed."
 	# Additional dependencies for ISA-L used in compression
 	apt-get install -y autoconf automake libtool help2man
+	# Additional dependencies for FUSE and CUSE
+	apt-get install -y libfuse3-dev
 	# Additional dependecies for nvmf performance test script
 	apt-get install -y python3-paramiko
 elif [ -f /etc/SuSE-release ] || [ -f /etc/SUSE-brand ]; then
@@ -111,6 +115,8 @@ elif [ -f /etc/SuSE-release ] || [ -f /etc/SUSE-brand ]; then
 	zypper install -y doxygen mscgen graphviz
 	# Additional dependencies for ISA-L used in compression
 	zypper install -y autoconf automake libtool help2man
+	# Additional dependencies for FUSE and CUSE
+	zypper install -y fuse3-devel
 elif [ $(uname -s) = "FreeBSD" ] ; then
 	pkg install -y gmake cunit openssl git devel/astyle bash py27-pycodestyle \
 		python misc/e2fsprogs-libuuid sysutils/sg3_utils nasm
@@ -140,6 +146,9 @@ elif [ -f /etc/arch-release ]; then
 	# Additional dependencies for ISA-L used in compression
 	pacman -Sy --needed --noconfirm autoconf automake libtool help2man
 
+	# Additional dependencies for FUSE and CUSE
+	pacman -Sy --needed --noconfirm fuse3
+
 	#fakeroot needed to instal via makepkg
 	pacman -Sy --needed --noconfirm fakeroot
 	su - $SUDO_USER -c "pushd /tmp;