From edc766541e03d457ce61cda5f4e8e201a6d2a738 Mon Sep 17 00:00:00 2001
From: zhangxiaoyu <zhangxiaoyu58@huawei.com>
Date: Tue, 1 Aug 2023 09:36:57 +0800
Subject: [PATCH] fix compile error

Signed-off-by: zhangxiaoyu <zhangxiaoyu58@huawei.com>
---
 meson.build                     |    2 +-
 src/lxc/af_unix.c               |   66 +
 src/lxc/af_unix.h               |    2 +
 src/lxc/attach.c                |   27 +-
 src/lxc/attach_options.h        |    3 +
 src/lxc/cgroups/cgfsng.c        |    3 +
 src/lxc/cgroups/cgroup.h        |    5 +
 src/lxc/cgroups/isulad_cgfsng.c | 2784 ++++++++++++++++++++-----------
 src/lxc/commands.c              |    4 +-
 src/lxc/conf.c                  |  197 ++-
 src/lxc/conf.h                  |    4 +
 src/lxc/confile.c               |   35 +-
 src/lxc/exec_commands.c         |   23 +-
 src/lxc/exec_commands.h         |    4 +-
 src/lxc/execute.c               |   15 +
 src/lxc/isulad_utils.c          |    6 +-
 src/lxc/isulad_utils.h          |    8 +-
 src/lxc/lsm/lsm.c               |   28 +
 src/lxc/lsm/lsm.h               |    5 +
 src/lxc/lsm/selinux.c           |    2 +-
 src/lxc/lxc.h                   |   11 +
 src/lxc/lxccontainer.c          |    4 +
 src/lxc/mainloop.c              |    2 +-
 src/lxc/mainloop.h              |    2 +-
 src/lxc/seccomp.c               |   52 +
 src/lxc/start.c                 |   56 +-
 src/lxc/sync.c                  |    6 +
 src/lxc/sync.h                  |   13 +-
 src/lxc/terminal.c              |  373 ++++-
 src/lxc/tools/lxc_ls.c          |    2 +-
 src/lxc/utils.c                 |    3 +
 src/tests/aa.c                  |    4 +
 src/tests/capabilities.c        |   12 +
 src/tests/mount_injection.c     |    4 +
 src/tests/proc_pid.c            |    4 +
 src/tests/rootfs_options.c      |    4 +
 src/tests/sys_mixed.c           |    4 +
 src/tests/sysctls.c             |    4 +
 38 files changed, 2700 insertions(+), 1083 deletions(-)

diff --git a/meson.build b/meson.build
index fda8045..05bcbb2 100644
--- a/meson.build
+++ b/meson.build
@@ -231,7 +231,7 @@ possible_link_flags = [
 ]
 
 if want_isulad
-    possible_cc_flags += ['-D_FORTIFY_SOURCE=2']
+    possible_cc_flags += ['-D_FORTIFY_SOURCE=2', '-O2']
     yajldep = dependency('yajl', version : '>=2')
     srcconf.set('HAVE_ISULAD', yajldep.found())
     liblxc_dependencies += yajldep
diff --git a/src/lxc/af_unix.c b/src/lxc/af_unix.c
index 6db1864..e0a4892 100644
--- a/src/lxc/af_unix.c
+++ b/src/lxc/af_unix.c
@@ -175,10 +175,18 @@ int __lxc_abstract_unix_send_two_fds(int fd, int fd_first, int fd_second,
 	return lxc_abstract_unix_send_fds(fd, fd_send, 2, data, size);
 }
 
+#ifdef HAVE_ISULAD
+static ssize_t lxc_abstract_unix_recv_fds_iov(int fd,
+					      struct unix_fds *ret_fds,
+					      struct iovec *ret_iov,
+					      size_t size_ret_iov,
+						  unsigned int timeout)
+#else
 static ssize_t lxc_abstract_unix_recv_fds_iov(int fd,
 					      struct unix_fds *ret_fds,
 					      struct iovec *ret_iov,
 					      size_t size_ret_iov)
+#endif
 {
 	__do_free char *cmsgbuf = NULL;
 	ssize_t ret;
@@ -209,6 +217,22 @@ static ssize_t lxc_abstract_unix_recv_fds_iov(int fd,
 	msg.msg_iov	= ret_iov;
 	msg.msg_iovlen	= size_ret_iov;
 
+#ifdef HAVE_ISULAD
+	struct timeval out;
+	if (timeout > 0) {
+		memset(&out, 0, sizeof(out));
+		out.tv_sec = timeout / 1000000;
+		out.tv_usec = timeout % 1000000;
+		ret = setsockopt(fd, SOL_SOCKET, SO_RCVTIMEO,
+		                 (const void *)&out, sizeof(out));
+		if (ret < 0) {
+			ERROR("Failed to set %u timeout on containter "
+			      "state socket", timeout);
+			return -1;
+		}
+	}
+#endif
+
 again:
 	ret = recvmsg(fd, &msg, MSG_CMSG_CLOEXEC);
 	if (ret < 0) {
@@ -329,7 +353,11 @@ ssize_t lxc_abstract_unix_recv_fds(int fd, struct unix_fds *ret_fds,
 	};
 	ssize_t ret;
 
+#ifdef HAVE_ISULAD
+	ret = lxc_abstract_unix_recv_fds_iov(fd, ret_fds, &iov, 1, 0);
+#else
 	ret = lxc_abstract_unix_recv_fds_iov(fd, ret_fds, &iov, 1);
+#endif
 	if (ret < 0)
 		return ret;
 
@@ -351,7 +379,11 @@ ssize_t lxc_abstract_unix_recv_one_fd(int fd, int *ret_fd, void *ret_data,
 		.fd_count_max = 1,
 	};
 
+#ifdef HAVE_ISULAD
+	ret = lxc_abstract_unix_recv_fds_iov(fd, fds, &iov, 1, 0);
+#else
 	ret = lxc_abstract_unix_recv_fds_iov(fd, fds, &iov, 1);
+#endif
 	if (ret < 0)
 		return ret;
 
@@ -381,7 +413,11 @@ ssize_t __lxc_abstract_unix_recv_two_fds(int fd, int *fd_first, int *fd_second,
 		.fd_count_max = 2,
 	};
 
+#ifdef HAVE_ISULAD
+	ret = lxc_abstract_unix_recv_fds_iov(fd, fds, &iov, 1, 0);
+#else
 	ret = lxc_abstract_unix_recv_fds_iov(fd, fds, &iov, 1);
+#endif
 	if (ret < 0)
 		return ret;
 
@@ -551,6 +587,36 @@ int lxc_socket_set_timeout(int fd, int rcv_timeout, int snd_timeout)
 }
 
 #ifdef HAVE_ISULAD
+ssize_t lxc_abstract_unix_recv_one_fd_timeout(int fd, int *ret_fd, void *ret_data,
+				      size_t size_ret_data, unsigned int timeout)
+{
+	call_cleaner(put_unix_fds) struct unix_fds *fds = NULL;
+	char buf[1] = {};
+	struct iovec iov = {
+		.iov_base	= ret_data ? ret_data : buf,
+		.iov_len	= ret_data ? size_ret_data : sizeof(buf),
+	};
+	ssize_t ret;
+
+	fds = &(struct unix_fds){
+		.fd_count_max = 1,
+	};
+
+	ret = lxc_abstract_unix_recv_fds_iov(fd, fds, &iov, 1, timeout);
+	if (ret < 0)
+		return ret;
+
+	if (ret == 0)
+		return ret_errno(ENODATA);
+
+	if (fds->fd_count_ret != fds->fd_count_max)
+		*ret_fd = -EBADF;
+	else
+		*ret_fd = move_fd(fds->fd[0]);
+
+	return ret;
+}
+
 int lxc_named_unix_open(const char *path, int type, int flags)
 {
 	__do_close int fd = -EBADF;
diff --git a/src/lxc/af_unix.h b/src/lxc/af_unix.h
index 605afc2..de5731f 100644
--- a/src/lxc/af_unix.h
+++ b/src/lxc/af_unix.h
@@ -169,6 +169,8 @@ static inline void put_unix_fds(struct unix_fds *fds)
 define_cleanup_function(struct unix_fds *, put_unix_fds);
 
 #ifdef HAVE_ISULAD
+__hidden extern ssize_t lxc_abstract_unix_recv_one_fd_timeout(int fd, int *ret_fd, void *ret_data,
+				     			 							  size_t size_ret_data, unsigned int timeout);
 __hidden extern int lxc_named_unix_open(const char *path, int type, int flags);
 __hidden extern int lxc_named_unix_connect(const char *path);
 #endif
diff --git a/src/lxc/attach.c b/src/lxc/attach.c
index 1a89001..066eb5c 100644
--- a/src/lxc/attach.c
+++ b/src/lxc/attach.c
@@ -1203,10 +1203,10 @@ __noreturn static void do_attach(struct attach_payload *ap)
 	sigset_t mask;
 
 	/*isulad: record errpipe fd*/
-	msg_fd = init_ctx->container->lxc_conf->errpipe[1];
-	init_ctx->container->lxc_conf->errpipe[1] = -1;
+	msg_fd = ctx->container->lxc_conf->errpipe[1];
+	ctx->container->lxc_conf->errpipe[1] = -1;
 	/*isulad: set system umask */
-	umask(init_ctx->container->lxc_conf->umask);
+	umask(ctx->container->lxc_conf->umask);
 
 	/*isulad: restore default signal handlers and unblock all signals*/
 	for (int i = 1; i < NSIG; i++)
@@ -1528,7 +1528,11 @@ __noreturn static void do_attach(struct attach_payload *ap)
 	put_attach_payload(ap);
 
 	/* We're done, so we can now do whatever the user intended us to do. */
+#ifdef HAVE_ISULAD
+	_exit(attach_function(attach_function_args, msg_fd));
+#else
 	_exit(attach_function(attach_function_args));
+#endif
 
 on_error:
 	ERROR("Failed to attach to container");
@@ -1668,7 +1672,7 @@ out:
 }
 
 static int attach_signal_handler(int fd, uint32_t events, void *data,
-			  struct lxc_epoll_descr *descr)
+			  struct lxc_async_descr *descr)
 {
 	int ret;
 	siginfo_t info;
@@ -1703,7 +1707,7 @@ static int isulad_setup_signal_fd(sigset_t *oldmask)
 	if (ret < 0)
 		return -EBADF;
 
-	for (int sig = 0; sig < (sizeof(signals) / sizeof(signals[0])); sig++) {
+	for (size_t sig = 0; sig < (sizeof(signals) / sizeof(signals[0])); sig++) {
 		ret = sigdelset(&mask, signals[sig]);
 		if (ret < 0)
 			return -EBADF;
@@ -1753,7 +1757,7 @@ int lxc_attach(struct lxc_container *container, lxc_attach_exec_t exec_function,
 
 	int isulad_sigfd;
 	sigset_t isulad_oldmask;
-	struct lxc_epoll_descr isulad_descr = {0};
+	struct lxc_async_descr isulad_descr = {0};
 #endif
 
 	if (!container)
@@ -1786,9 +1790,9 @@ int lxc_attach(struct lxc_container *container, lxc_attach_exec_t exec_function,
 
 #ifdef HAVE_ISULAD
 	// always switch uid and gid for attach
-	if (options->uid == -1)
+	if (options->uid == (uid_t)-1)
 		options->uid = conf->init_uid;
-	if (options->gid == -1)
+	if (options->gid == (gid_t)-1)
 		options->gid = conf->init_gid;
 #endif
 
@@ -2111,7 +2115,11 @@ int lxc_attach(struct lxc_container *container, lxc_attach_exec_t exec_function,
 		goto on_error;
 
 	/* Setup resource limits */
+#ifdef HAVE_ISULAD
+	ret = setup_resource_limits(conf, pid, -1);
+#else
 	ret = setup_resource_limits(conf, pid);
+#endif
 	if (ret < 0)
 		goto on_error;
 
@@ -2228,7 +2236,8 @@ int lxc_attach(struct lxc_container *container, lxc_attach_exec_t exec_function,
 		goto close_mainloop;
 	}
 	if (options->attach_flags & LXC_ATTACH_TERMINAL) {
-		ret = lxc_mainloop_add_handler(&descr, isulad_sigfd, attach_signal_handler, &tmp_pid);
+		ret = lxc_mainloop_add_handler(&descr, isulad_sigfd, attach_signal_handler, default_cleanup_handler, &tmp_pid,
+									   "attach_signal_handler");
 		if (ret < 0) {
 			ERROR("Failed to add signal handler for %d to mainloop", tmp_pid);
 			goto close_mainloop;
diff --git a/src/lxc/attach_options.h b/src/lxc/attach_options.h
index a4052fb..fe8bf6d 100644
--- a/src/lxc/attach_options.h
+++ b/src/lxc/attach_options.h
@@ -4,6 +4,9 @@
 #define __LXC_ATTACH_OPTIONS_H
 
 #include <sys/types.h>
+#ifdef HAVE_ISULAD
+#include <stdbool.h>
+#endif
 
 #ifdef  __cplusplus
 extern "C" {
diff --git a/src/lxc/cgroups/cgfsng.c b/src/lxc/cgroups/cgfsng.c
index cecc9bc..4e4ae0c 100644
--- a/src/lxc/cgroups/cgfsng.c
+++ b/src/lxc/cgroups/cgfsng.c
@@ -3634,6 +3634,9 @@ static int __initialize_cgroups(struct cgroup_ops *ops, bool relative,
 			controller_list = unified_controllers(dfd, "cgroup.controllers");
 			if (!controller_list) {
 				TRACE("No controllers are enabled for delegation in the unified hierarchy");
+#ifdef HAVE_ISULAD
+				ops->no_controller = true;
+#endif
 				controller_list = list_new();
 				if (!controller_list)
 					return syserror_set(-ENOMEM, "Failed to create empty controller list");
diff --git a/src/lxc/cgroups/cgroup.h b/src/lxc/cgroups/cgroup.h
index ebfd3a1..d9159f4 100644
--- a/src/lxc/cgroups/cgroup.h
+++ b/src/lxc/cgroups/cgroup.h
@@ -208,6 +208,11 @@ struct cgroup_ops {
 	char *container_limit_cgroup;
 	char *monitor_cgroup;
 
+#ifdef HAVE_ISULAD
+	int errfd;
+	bool no_controller;
+#endif
+
 	/* @hierarchies
 	 * - A NULL-terminated array of struct hierarchy, one per legacy
 	 *   hierarchy. No duplicates. First sufficient, writeable mounted
diff --git a/src/lxc/cgroups/isulad_cgfsng.c b/src/lxc/cgroups/isulad_cgfsng.c
index 38ad677..1160af5 100644
--- a/src/lxc/cgroups/isulad_cgfsng.c
+++ b/src/lxc/cgroups/isulad_cgfsng.c
@@ -34,6 +34,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <sys/epoll.h>
 #include <sys/types.h>
 #include <unistd.h>
 
@@ -43,41 +44,55 @@
 #include "cgroup2_devices.h"
 #include "cgroup_utils.h"
 #include "commands.h"
+#include "commands_utils.h"
 #include "conf.h"
 #include "config.h"
 #include "log.h"
 #include "macro.h"
 #include "mainloop.h"
 #include "memory_utils.h"
+#include "open_utils.h"
 #include "storage/storage.h"
 #include "utils.h"
 
-#ifndef HAVE_STRLCPY
+#if !HAVE_STRLCPY
 #include "include/strlcpy.h"
 #endif
 
-#ifndef HAVE_STRLCAT
+#if !HAVE_STRLCAT
 #include "include/strlcat.h"
 #endif
 
+#if HAVE_LIBSYSTEMD
+#include <systemd/sd-bus.h>
+#include <systemd/sd-event.h>
+#endif
+
 lxc_log_define(isulad_cgfsng, cgroup);
 
-/* Given a pointer to a null-terminated array of pointers, realloc to add one
+/*
+ * Given a pointer to a null-terminated array of pointers, realloc to add one
  * entry, and point the new entry to NULL. Do not fail. Return the index to the
  * second-to-last entry - that is, the one which is now available for use
  * (keeping the list null-terminated).
  */
-static int append_null_to_list(void ***list)
+static int cg_list_add(void ***list)
 {
-	int newentry = 0;
+	int idx = 0;
+	void **p;
 
 	if (*list)
-		for (; (*list)[newentry]; newentry++)
+		for (; (*list)[idx]; idx++)
 			;
 
-	*list = must_realloc(*list, (newentry + 2) * sizeof(void **));
-	(*list)[newentry + 1] = NULL;
-	return newentry;
+	p = realloc(*list, (idx + 2) * sizeof(void **));
+	if (!p)
+		return ret_errno(ENOMEM);
+
+	p[idx + 1] = NULL;
+	*list = p;
+
+	return idx;
 }
 
 /* Given a null-terminated array of strings, check whether @entry is one of the
@@ -95,63 +110,10 @@ static bool string_in_list(char **list, const char *entry)
 	return false;
 }
 
-/* Return a copy of @entry prepending "name=", i.e.  turn "systemd" into
- * "name=systemd". Do not fail.
- */
-static char *cg_legacy_must_prefix_named(char *entry)
-{
-	size_t len;
-	char *prefixed;
-
-	len = strlen(entry);
-	prefixed = must_realloc(NULL, len + 6);
-
-	memcpy(prefixed, "name=", STRLITERALLEN("name="));
-	memcpy(prefixed + STRLITERALLEN("name="), entry, len);
-	prefixed[len + 5] = '\0';
-
-	return prefixed;
-}
-
-/* Append an entry to the clist. Do not fail. @clist must be NULL the first time
- * we are called.
- *
- * We also handle named subsystems here. Any controller which is not a kernel
- * subsystem, we prefix "name=". Any which is both a kernel and named subsystem,
- * we refuse to use because we're not sure which we have here.
- * (TODO: We could work around this in some cases by just remounting to be
- * unambiguous, or by comparing mountpoint contents with current cgroup.)
- *
- * The last entry will always be NULL.
- */
-static void must_append_controller(char **klist, char **nlist, char ***clist,
-				   char *entry)
-{
-	int newentry;
-	char *copy;
-
-	if (string_in_list(klist, entry) && string_in_list(nlist, entry)) {
-		ERROR("Refusing to use ambiguous controller \"%s\"", entry);
-		ERROR("It is both a named and kernel subsystem");
-		return;
-	}
-
-	newentry = append_null_to_list((void ***)clist);
-
-	if (strncmp(entry, "name=", 5) == 0)
-		copy = must_copy_string(entry);
-	else if (string_in_list(klist, entry))
-		copy = must_copy_string(entry);
-	else
-		copy = cg_legacy_must_prefix_named(entry);
-
-	(*clist)[newentry] = copy;
-}
-
 /* Given a handler's cgroup data, return the struct hierarchy for the controller
  * @c, or NULL if there is none.
  */
-struct hierarchy *get_hierarchy(struct cgroup_ops *ops, const char *controller)
+static struct hierarchy *get_hierarchy(const struct cgroup_ops *ops, const char *controller)
 {
 	if (!ops->hierarchies)
 		return log_trace_errno(NULL, errno, "There are no useable cgroup controllers");
@@ -159,15 +121,28 @@ struct hierarchy *get_hierarchy(struct cgroup_ops *ops, const char *controller)
 	for (int i = 0; ops->hierarchies[i]; i++) {
 		if (!controller) {
 			/* This is the empty unified hierarchy. */
-			if (ops->hierarchies[i]->controllers &&
-			    !ops->hierarchies[i]->controllers[0])
+			if (ops->hierarchies[i]->controllers && !ops->hierarchies[i]->controllers[0])
 				return ops->hierarchies[i];
+
 			continue;
-		} else if (pure_unified_layout(ops) &&
-			   strcmp(controller, "devices") == 0) {
-			if (ops->unified->bpf_device_controller)
-				return ops->unified;
-			break;
+		}
+
+		/*
+		 * Handle controllers with significant implementation changes
+		 * from cgroup to cgroup2.
+		 */
+		if (pure_unified_layout(ops)) {
+			if (strequal(controller, "devices")) {
+				if (device_utility_controller(ops->unified))
+					return ops->unified;
+
+				break;
+			} else if (strequal(controller, "freezer")) {
+				if (freezer_utility_controller(ops->unified))
+					return ops->unified;
+
+				break;
+			}
 		}
 
 		if (string_in_list(ops->hierarchies[i]->controllers, controller))
@@ -182,6 +157,38 @@ struct hierarchy *get_hierarchy(struct cgroup_ops *ops, const char *controller)
 	return ret_set_errno(NULL, ENOENT);
 }
 
+int prepare_cgroup_fd(const struct cgroup_ops *ops, struct cgroup_fd *fd, bool limit)
+{
+	int dfd;
+	const struct hierarchy *h;
+
+	h = get_hierarchy(ops, fd->controller);
+	if (!h)
+		return ret_errno(ENOENT);
+
+	/*
+	 * The client requested that the controller must be in a specific
+	 * cgroup version.
+	 */
+	if (fd->type != 0 && (cgroupfs_type_magic_t)fd->type != h->fs_type)
+		return ret_errno(EINVAL);
+
+	if (limit)
+		dfd = h->dfd_con;
+	else
+		dfd = h->dfd_lim;
+	if (dfd < 0)
+		return ret_errno(EBADF);
+
+	fd->layout = ops->cgroup_layout;
+	fd->type = h->fs_type;
+	if (fd->type == UNIFIED_HIERARCHY)
+		fd->utilities = h->utilities;
+	fd->fd = dfd;
+
+	return 0;
+}
+
 #define BATCH_SIZE 50
 static void batch_realloc(char **mem, size_t oldlen, size_t newlen)
 {
@@ -223,44 +230,24 @@ static char *read_file(const char *fnam)
 
 static inline bool is_unified_hierarchy(const struct hierarchy *h)
 {
-	return h->version == CGROUP2_SUPER_MAGIC;
-}
-
-/* Given two null-terminated lists of strings, return true if any string is in
- * both.
- */
-static bool controller_lists_intersect(char **l1, char **l2)
-{
-	if (!l1 || !l2)
-		return false;
-
-	for (int i = 0; l1[i]; i++)
-		if (string_in_list(l2, l1[i]))
-			return true;
-
-	return false;
+	return h->fs_type == UNIFIED_HIERARCHY;
 }
 
-/* For a null-terminated list of controllers @clist, return true if any of those
- * controllers is already listed the null-terminated list of hierarchies @hlist.
- * Realistically, if one is present, all must be present.
- */
-static bool controller_list_is_dup(struct hierarchy **hlist, char **clist)
+static char *trim(char *s)
 {
-	if (!hlist)
-		return false;
+	size_t len;
 
-	for (int i = 0; hlist[i]; i++)
-		if (controller_lists_intersect(hlist[i]->controllers, clist))
-			return true;
+	len = strlen(s);
+	while ((len > 1) && (s[len - 1] == '\n'))
+		s[--len] = '\0';
 
-	return false;
+	return s;
 }
 
 /* Return true if the controller @entry is found in the null-terminated list of
  * hierarchies @hlist.
  */
-static bool controller_found(struct hierarchy **hlist, char *entry)
+static bool controller_available(struct hierarchy **hlist, char *entry)
 {
 	if (!hlist)
 		return false;
@@ -272,10 +259,7 @@ static bool controller_found(struct hierarchy **hlist, char *entry)
 	return false;
 }
 
-/* Return true if all of the controllers which we require have been found.  The
- * required list is  freezer and anything in lxc.cgroup.use.
- */
-static bool all_controllers_found(struct cgroup_ops *ops)
+static bool controllers_available(struct cgroup_ops *ops)
 {
 	struct hierarchy **hlist;
 
@@ -284,335 +268,139 @@ static bool all_controllers_found(struct cgroup_ops *ops)
 
 	hlist = ops->hierarchies;
 	for (char **cur = ops->cgroup_use; cur && *cur; cur++)
-		if (!controller_found(hlist, *cur))
-			return log_error(false, "No %s controller mountpoint found", *cur);
+		if (!controller_available(hlist, *cur))
+			return log_error(false, "The %s controller found", *cur);
 
 	return true;
 }
 
-/* Get the controllers from a mountinfo line There are other ways we could get
- * this info. For lxcfs, field 3 is /cgroup/controller-list. For cgroupfs, we
- * could parse the mount options. But we simply assume that the mountpoint must
- * be /sys/fs/cgroup/controller-list
- */
-static char **cg_hybrid_get_controllers(char **klist, char **nlist, char *line,
-					int type)
+static char **list_new(void)
 {
-	/* The fourth field is /sys/fs/cgroup/comma-delimited-controller-list
-	 * for legacy hierarchies.
-	 */
-	__do_free_string_list char **aret = NULL;
-	int i;
-	char *p2, *tok;
-	char *p = line, *sep = ",";
-
-	for (i = 0; i < 4; i++) {
-		p = strchr(p, ' ');
-		if (!p)
-			return NULL;
-		p++;
-	}
-
-	/* Note, if we change how mountinfo works, then our caller will need to
-	 * verify /sys/fs/cgroup/ in this field.
-	 */
-	if (strncmp(p, DEFAULT_CGROUP_MOUNTPOINT "/", 15) != 0)
-		return log_warn(NULL, "Found hierarchy not under " DEFAULT_CGROUP_MOUNTPOINT ": \"%s\"", p);
-
-	p += 15;
-	p2 = strchr(p, ' ');
-	if (!p2)
-		return log_error(NULL, "Corrupt mountinfo");
-	*p2 = '\0';
-
-	if (type == CGROUP_SUPER_MAGIC) {
-		__do_free char *dup = NULL;
-
-		/* strdup() here for v1 hierarchies. Otherwise
-		 * lxc_iterate_parts() will destroy mountpoints such as
-		 * "/sys/fs/cgroup/cpu,cpuacct".
-		 */
-		dup = must_copy_string(p);
-		if (!dup)
-			return NULL;
-
-		lxc_iterate_parts (tok, dup, sep)
-			must_append_controller(klist, nlist, &aret, tok);
-	}
-	*p2 = ' ';
-
-	return move_ptr(aret);
-}
+	__do_free_string_list char **list = NULL;
+	int idx;
 
-static char **cg_unified_make_empty_controller(void)
-{
-	__do_free_string_list char **aret = NULL;
-	int newentry;
+	idx = cg_list_add((void ***)&list);
+	if (idx < 0)
+		return NULL;
 
-	newentry = append_null_to_list((void ***)&aret);
-	aret[newentry] = NULL;
-	return move_ptr(aret);
+	list[idx] = NULL;
+	return move_ptr(list);
 }
 
-static char **cg_unified_get_controllers(const char *file)
+static int list_add_string(char ***list, char *entry)
 {
-	__do_free char *buf = NULL;
-	__do_free_string_list char **aret = NULL;
-	char *sep = " \t\n";
-	char *tok;
-
-	buf = read_file(file);
-	if (!buf)
-		return NULL;
+	__do_free char *dup = NULL;
+	int idx;
 
-	lxc_iterate_parts(tok, buf, sep) {
-		int newentry;
-		char *copy;
+	dup = strdup(entry);
+	if (!dup)
+		return ret_errno(ENOMEM);
 
-		newentry = append_null_to_list((void ***)&aret);
-		copy = must_copy_string(tok);
-		aret[newentry] = copy;
-	}
+	idx = cg_list_add((void ***)list);
+	if (idx < 0)
+		return idx;
 
-	return move_ptr(aret);
+	(*list)[idx] = move_ptr(dup);
+	return 0;
 }
 
-static struct hierarchy *add_hierarchy(struct hierarchy ***h, char **clist, char *mountpoint,
-				       char *container_base_path, int type)
+static char **list_add_controllers(char *controllers)
 {
-	struct hierarchy *new;
-	int newentry;
+	__do_free_string_list char **list = NULL;
+	char *it;
 
-	new = zalloc(sizeof(*new));
-	new->controllers = clist;
-	new->at_mnt = mountpoint;
-	new->at_base = container_base_path;
-	new->fs_type = type;
-	new->dfd_con = -EBADF;
-	new->dfd_mon = -EBADF;
-
-	newentry = append_null_to_list((void ***)h);
-	(*h)[newentry] = new;
-	return new;
-}
-
-/* Get a copy of the mountpoint from @line, which is a line from
- * /proc/self/mountinfo.
- */
-static char *cg_hybrid_get_mountpoint(char *line)
-{
-	char *p = line, *sret = NULL;
-	size_t len;
-	char *p2;
+	lxc_iterate_parts(it, controllers, ", \t\n") {
+		int ret;
 
-	for (int i = 0; i < 4; i++) {
-		p = strchr(p, ' ');
-		if (!p)
+		ret = list_add_string(&list, it);
+		if (ret < 0)
 			return NULL;
-		p++;
 	}
 
-	if (strncmp(p, DEFAULT_CGROUP_MOUNTPOINT "/", 15) != 0)
-		return NULL;
-
-	p2 = strchr(p + 15, ' ');
-	if (!p2)
-		return NULL;
-	*p2 = '\0';
-
-	len = strlen(p);
-	sret = must_realloc(NULL, len + 1);
-	memcpy(sret, p, len);
-	sret[len] = '\0';
-
-	return sret;
+	return move_ptr(list);
 }
 
-/* Given a multi-line string, return a null-terminated copy of the current line. */
-static char *copy_to_eol(char *p)
+static char **unified_controllers(int dfd, const char *file)
 {
-	char *p2, *sret;
-	size_t len;
+	__do_free char *buf = NULL;
 
-	p2 = strchr(p, '\n');
-	if (!p2)
+	buf = read_file_at(dfd, file, PROTECT_OPEN, 0);
+	if (!buf)
 		return NULL;
 
-	len = p2 - p;
-	sret = must_realloc(NULL, len + 1);
-	memcpy(sret, p, len);
-	sret[len] = '\0';
-
-	return sret;
+	return list_add_controllers(buf);
 }
 
-/* cgline: pointer to character after the first ':' in a line in a \n-terminated
- * /proc/self/cgroup file. Check whether controller c is present.
- */
-static bool controller_in_clist(char *cgline, char *c)
+static bool skip_hierarchy(const struct cgroup_ops *ops, char **controllers)
 {
-	__do_free char *tmp = NULL;
-	char *tok, *eol;
-	size_t len;
-
-	eol = strchr(cgline, ':');
-	if (!eol)
+	if (!ops->cgroup_use)
 		return false;
 
-	len = eol - cgline;
-	tmp = must_realloc(NULL, len + 1);
-	memcpy(tmp, cgline, len);
-	tmp[len] = '\0';
-
-	lxc_iterate_parts(tok, tmp, ",")
-		if (strcmp(tok, c) == 0)
-			return true;
-
-	return false;
-}
-
-/* @basecginfo is a copy of /proc/$$/cgroup. Return the current cgroup for
- * @controller.
- */
-static char *cg_hybrid_get_current_cgroup(char *basecginfo, char *controller,
-					  int type)
-{
-	char *p = basecginfo;
-
-	for (;;) {
-		bool is_cgv2_base_cgroup = false;
-
-		/* cgroup v2 entry in "/proc/<pid>/cgroup": "0::/some/path" */
-		if ((type == CGROUP2_SUPER_MAGIC) && (*p == '0'))
-			is_cgv2_base_cgroup = true;
+	for (char **cur_ctrl = controllers; cur_ctrl && *cur_ctrl; cur_ctrl++) {
+		bool found = false;
 
-		p = strchr(p, ':');
-		if (!p)
-			return NULL;
-		p++;
+		for (char **cur_use = ops->cgroup_use; cur_use && *cur_use; cur_use++) {
+			if (!strequal(*cur_use, *cur_ctrl))
+				continue;
 
-		if (is_cgv2_base_cgroup || (controller && controller_in_clist(p, controller))) {
-			p = strchr(p, ':');
-			if (!p)
-				return NULL;
-			p++;
-			return copy_to_eol(p);
+			found = true;
+			break;
 		}
 
-		p = strchr(p, '\n');
-		if (!p)
-			return NULL;
-		p++;
-	}
-}
-
-static void must_append_string(char ***list, char *entry)
-{
-	int newentry;
-	char *copy;
-
-	newentry = append_null_to_list((void ***)list);
-	copy = must_copy_string(entry);
-	(*list)[newentry] = copy;
-}
-
-static int get_existing_subsystems(char ***klist, char ***nlist)
-{
-	__do_free char *line = NULL;
-	__do_fclose FILE *f = NULL;
-	size_t len = 0;
-
-	f = fopen("/proc/self/cgroup", "re");
-	if (!f)
-		return -1;
-
-	while (getline(&line, &len, f) != -1) {
-		char *p, *p2, *tok;
-		p = strchr(line, ':');
-		if (!p)
-			continue;
-		p++;
-		p2 = strchr(p, ':');
-		if (!p2)
-			continue;
-		*p2 = '\0';
-
-		/* If the kernel has cgroup v2 support, then /proc/self/cgroup
-		 * contains an entry of the form:
-		 *
-		 *	0::/some/path
-		 *
-		 * In this case we use "cgroup2" as controller name.
-		 */
-		if ((p2 - p) == 0) {
-			must_append_string(klist, "cgroup2");
+		if (found)
 			continue;
-		}
 
-		lxc_iterate_parts(tok, p, ",") {
-			if (strncmp(tok, "name=", 5) == 0)
-				must_append_string(nlist, tok);
-			else
-				must_append_string(klist, tok);
-		}
+		return true;
 	}
 
-	return 0;
+	return false;
 }
 
-static char *trim(char *s)
+static int cgroup_hierarchy_add(struct cgroup_ops *ops, int dfd_mnt, char *mnt,
+				int dfd_base, char *base_cgroup,
+				char **controllers, cgroupfs_type_magic_t fs_type)
 {
-	size_t len;
-
-	len = strlen(s);
-	while ((len > 1) && (s[len - 1] == '\n'))
-		s[--len] = '\0';
+	__do_free struct hierarchy *new = NULL;
+	int idx;
 
-	return s;
-}
+	if (abspath(base_cgroup))
+		return syserror_set(-EINVAL, "Container base path must be relative to controller mount");
 
-static void lxc_cgfsng_print_hierarchies(struct cgroup_ops *ops)
-{
-	int i;
-	struct hierarchy **it;
+	new = zalloc(sizeof(*new));
+	if (!new)
+		return ret_errno(ENOMEM);
 
-	if (!ops->hierarchies) {
-		TRACE("  No hierarchies found");
-		return;
-	}
+	new->dfd_con		= -EBADF;
+	new->dfd_lim		= -EBADF;
+	new->dfd_mon		= -EBADF;
 
-	TRACE("  Hierarchies:");
-	for (i = 0, it = ops->hierarchies; it && *it; it++, i++) {
-		int j;
-		char **cit;
+	new->fs_type		= fs_type;
+	new->controllers	= controllers;
+	new->at_mnt		= mnt;
+	new->at_base		= base_cgroup;
 
-		TRACE("  %d: base_cgroup: %s", i, (*it)->at_base ? (*it)->at_base : "(null)");
-		TRACE("      at_mnt:  %s", (*it)->at_mnt ? (*it)->at_mnt : "(null)");
-		TRACE("      controllers:");
-		for (j = 0, cit = (*it)->controllers; cit && *cit; cit++, j++)
-			TRACE("      %d: %s", j, *cit);
-	}
-}
+	new->dfd_mnt		= dfd_mnt;
+	new->dfd_base		= dfd_base;
 
-static void lxc_cgfsng_print_basecg_debuginfo(char *basecginfo, char **klist,
-					      char **nlist)
-{
-	int k;
-	char **it;
+	TRACE("Adding cgroup hierarchy mounted at %s and base cgroup %s",
+	      mnt, maybe_empty(base_cgroup));
+	for (char *const *it = new->controllers; it && *it; it++)
+		TRACE("The hierarchy contains the %s controller", *it);
 
-	TRACE("basecginfo is:");
-	TRACE("%s", basecginfo);
+	idx = cg_list_add((void ***)&ops->hierarchies);
+	if (idx < 0)
+		return ret_errno(idx);
 
-	for (k = 0, it = klist; it && *it; it++, k++)
-		TRACE("kernel subsystem %d: %s", k, *it);
+	if (fs_type == UNIFIED_HIERARCHY)
+		ops->unified = new;
+	(ops->hierarchies)[idx] = move_ptr(new);
 
-	for (k = 0, it = nlist; it && *it; it++, k++)
-		TRACE("named subsystem %d: %s", k, *it);
+	return 0;
 }
 
 struct generic_userns_exec_data {
 	struct hierarchy **hierarchies;
-	const char *container_cgroup;
+	const char *path_prune;
 	struct lxc_conf *conf;
 	uid_t origuid; /* target uid in parent namespace */
 	char *path;
@@ -655,7 +443,7 @@ static int isulad_cgroup_tree_remove_wrapper(void *data)
 	gid_t nsgid = (arg->conf->root_nsgid_map != NULL) ? 0 : arg->conf->init_gid;
 	int ret;
 
-	if (!lxc_setgroups(0, NULL) && errno != EPERM)
+	if (!lxc_drop_groups() && errno != EPERM)
 		return log_error_errno(-1, errno, "Failed to setgroups(0, NULL)");
 
 	ret = setresgid(nsgid, nsgid, nsgid);
@@ -668,7 +456,7 @@ static int isulad_cgroup_tree_remove_wrapper(void *data)
 		return log_error_errno(-1, errno, "Failed to setresuid(%d, %d, %d)",
 				       (int)nsuid, (int)nsuid, (int)nsuid);
 
-	return isulad_cgroup_tree_remove(arg->hierarchies, arg->container_cgroup);
+	return isulad_cgroup_tree_remove(arg->hierarchies, arg->path_prune);
 }
 
 __cgfsng_ops static bool isulad_cgfsng_payload_destroy(struct cgroup_ops *ops,
@@ -707,10 +495,10 @@ __cgfsng_ops static bool isulad_cgfsng_payload_destroy(struct cgroup_ops *ops,
 		WARN("Failed to detach bpf program from cgroup");
 #endif
 
-	if (handler->conf && !lxc_list_empty(&handler->conf->id_map)) {
+	if (!list_empty(&handler->conf->id_map) && !handler->am_root) {
 		struct generic_userns_exec_data wrap = {
 			.conf			= handler->conf,
-			.container_cgroup	= ops->container_cgroup,
+			.path_prune		= ops->container_limit_cgroup,
 			.hierarchies		= ops->hierarchies,
 			.origuid		= 0,
 		};
@@ -733,58 +521,408 @@ __cgfsng_ops static void isulad_cgfsng_monitor_destroy(struct cgroup_ops *ops,
 	return;
 }
 
-__cgfsng_ops static inline bool isulad_cgfsng_monitor_create(struct cgroup_ops *ops,
-						      struct lxc_handler *handler)
+#define SYSTEMD_SCOPE_FAILED 2
+#define SYSTEMD_SCOPE_UNSUPP 1
+#define SYSTEMD_SCOPE_SUCCESS 0
+
+#if HAVE_LIBSYSTEMD
+struct sd_callback_data {
+	char *scope_name;
+	bool job_complete;
+};
+
+static int systemd_jobremoved_callback(sd_bus_message *m, void *userdata, sd_bus_error *error)
 {
-	return true;
+	char *path, *unit, *result;
+	struct sd_callback_data *sd_data = userdata;
+	uint32_t id;
+	int r;
+
+	r = sd_bus_message_read(m, "uoss", &id, &path, &unit, &result);
+	if (r < 0)
+		return log_error(-1, "bad message received in callback: %s", strerror(-r));
+
+	if (sd_data->scope_name && strcmp(unit, sd_data->scope_name) != 0)
+		return log_trace(-1, "unit was '%s' not '%s'", unit, sd_data->scope_name);
+	if (strcmp(result, "done") == 0) {
+		sd_data->job_complete = true;
+		return log_info(1, "job is done");
+	}
+	return log_debug(0, "result was '%s', not 'done'", result);
 }
 
-static bool isulad_copy_parent_file(char *path, char *file)
+#define DESTINATION "org.freedesktop.systemd1"
+#define PATH "/org/freedesktop/systemd1"
+#define INTERFACE "org.freedesktop.systemd1.Manager"
+#define MEMBER "StartTransientUnit"
+static bool start_scope(sd_bus *bus, struct sd_callback_data *data, struct sd_event *event)
 {
-	int ret;
-	int len = 0;
-	char *value = NULL;
-	char *current = NULL;
-	char *fpath = NULL;
-	char *lastslash = NULL;
-	char oldv;
-
-	fpath = must_make_path(path, file, NULL);
-	current = read_file(fpath);
-
-	if (current == NULL) {
-		SYSERROR("Failed to read file \"%s\"", fpath);
-		free(fpath);
-		return false;
+	__attribute__((__cleanup__(sd_bus_error_free))) sd_bus_error error = SD_BUS_ERROR_NULL;;
+	__attribute__((__cleanup__(sd_bus_message_unrefp))) sd_bus_message *reply = NULL;
+	__attribute__((__cleanup__(sd_bus_message_unrefp))) sd_bus_message *m = NULL;
+	char *path = NULL;
+	int r;
+
+	r = sd_bus_message_new_method_call(bus, &m,
+		DESTINATION, PATH, INTERFACE, MEMBER);
+	if (r < 0)
+		return log_error(false, "Failed creating sdbus message");
+
+	r = sd_bus_message_append(m, "ss", data->scope_name, "fail");
+	if (r < 0)
+		return log_error(false, "Failed setting systemd scope name");
+
+	r = sd_bus_message_open_container(m, 'a', "(sv)");
+	if (r < 0)
+		return log_error(false, "Failed allocating sdbus msg properties");
+
+	r = sd_bus_message_append(m, "(sv)(sv)(sv)",
+		"PIDs", "au", 1, getpid(),
+		"Delegate", "b", 1,
+		"CollectMode", "s", "inactive-or-failed");
+	if (r < 0)
+		return log_error(false, "Failed setting properties on sdbus message");
+
+	r = sd_bus_message_close_container(m);
+	if (r < 0)
+		return log_error(false, "Failed closing sdbus message properties");
+
+	r = sd_bus_message_append(m, "a(sa(sv))", 0);
+	if (r < 0)
+		return log_error(false, "Failed appending aux boilerplate\n");
+
+	r = sd_bus_call(NULL, m, 0, &error, &reply);
+	if (r < 0)
+		return log_error(false,  "Failed sending sdbus message: %s", error.message);
+
+	/* Parse the response message */
+	r = sd_bus_message_read(reply, "o", &path);
+	if (r < 0)
+		return log_error(false, "Failed to parse response message: %s", strerror(-r));
+
+	/* Now spin up a mini-event-loop to wait for the "job completed" message */
+	int tries = 0;
+
+	while (!data->job_complete) {
+		r = sd_event_run(event, 1000 * 1000);
+		if (r < 0) {
+			log_debug(stderr, "Error waiting for JobRemoved: %s\n", strerror(-r));
+			continue;
+		}
+		if (data->job_complete || tries == 5)
+			break;
+		if (r > 0) {
+			log_trace(stderr, "Debug: we processed an event (%d), but not the one we wanted\n", r);
+			continue;
+		}
+		if (r == 0) // timeout
+			tries++;
 	}
-
-	if (strcmp(current, "\n") != 0) {
-		free(fpath);
-		free(current);
-		return true;
+	if (!data->job_complete) {
+		return log_error(false, "Error: %s job was never removed", data->scope_name);
 	}
+	return true;
+}
 
-	free(fpath);
-	free(current);
+static bool string_pure_unified_system(char *contents)
+{
+	char *p;
+	bool first_line_read = false;
 
-	lastslash = strrchr(path, '/');
-	if (lastslash == NULL) {
-		ERROR("Failed to detect \"/\" in \"%s\"", path);
-		return false;
+	lxc_iterate_parts(p, contents, "\n") {
+		if (first_line_read) // if >1 line, this is not pure unified
+			return false;
+		first_line_read = true;
+
+		if (strlen(p) > 3 && strncmp(p, "0:", 2) == 0)
+			return true;
 	}
-	oldv = *lastslash;
-	*lastslash = '\0';
-	fpath = must_make_path(path, file, NULL);
-	*lastslash = oldv;
-	len = lxc_read_from_file(fpath, NULL, 0);
-	if (len <= 0)
-		goto on_error;
 
-	value = must_realloc(NULL, len + 1);
-	ret = lxc_read_from_file(fpath, value, len);
-	if (ret != len)
-		goto on_error;
-	free(fpath);
+	return false;
+}
+
+/*
+ * Only call get_current_unified_cgroup() when we are in a pure
+ * unified (v2-only) cgroup
+ */
+static char *get_current_unified_cgroup(void)
+{
+	__do_free char *buf = NULL;
+	__do_free_string_list char **list = NULL;
+	char *p;
+
+	buf = read_file_at(-EBADF, "/proc/self/cgroup", PROTECT_OPEN, 0);
+	if (!buf)
+		return NULL;
+
+	if (!string_pure_unified_system(buf))
+		return NULL;
+
+	// 0::/user.slice/user-1000.slice/session-136.scope
+	// Get past the "0::"
+	p = buf;
+	if (strnequal(p, "0::", STRLITERALLEN("0::")))
+		p += STRLITERALLEN("0::");
+
+	return strdup(p);
+}
+
+static bool pure_unified_system(void)
+{
+	__do_free char *buf = NULL;
+
+	buf = read_file_at(-EBADF, "/proc/self/cgroup", PROTECT_OPEN, 0);
+	if (!buf)
+		return false;
+
+	return string_pure_unified_system(buf);
+}
+
+#define MEMBER_JOIN "AttachProcessesToUnit"
+static bool enter_scope(char *scope_name, pid_t pid)
+{
+	__attribute__((__cleanup__(sd_bus_unrefp))) sd_bus *bus = NULL;
+	__attribute__((__cleanup__(sd_bus_error_free))) sd_bus_error error = SD_BUS_ERROR_NULL;;
+	__attribute__((__cleanup__(sd_bus_message_unrefp))) sd_bus_message *reply = NULL;
+	__attribute__((__cleanup__(sd_bus_message_unrefp))) sd_bus_message *m = NULL;
+	int r;
+
+	r = sd_bus_open_user(&bus);
+	if (r < 0)
+		return log_error(false, "Failed to connect to user bus: %s", strerror(-r));
+
+	r = sd_bus_message_new_method_call(bus, &m,
+		DESTINATION, PATH, INTERFACE, MEMBER_JOIN);
+	if (r < 0)
+		return log_error(false, "Failed creating sdbus message");
+
+	r = sd_bus_message_append(m, "ssau", scope_name, "/init", 1, pid);
+	if (r < 0)
+		return log_error(false, "Failed setting systemd scope name");
+
+
+	r = sd_bus_call(NULL, m, 0, &error, &reply);
+	if (r < 0)
+		return log_error(false,  "Failed sending sdbus message: %s", error.message);
+
+	return true;
+}
+
+static bool enable_controllers_delegation(int fd_dir, char *cg)
+{
+	__do_free char *rbuf = NULL;
+	__do_free char *wbuf = NULL;
+	__do_free_string_list char **cpulist = NULL;
+	char *controller;
+	size_t full_len = 0;
+	bool first = true;
+	int ret;
+
+	rbuf = read_file_at(fd_dir, "cgroup.controllers", PROTECT_OPEN, 0);
+	if (!rbuf)
+		return false;
+
+	lxc_iterate_parts(controller, rbuf, " ") {
+		full_len += strlen(controller) + 2;
+		wbuf = must_realloc(wbuf, full_len + 1);
+		if (first) {
+			wbuf[0] = '\0';
+			first = false;
+		} else {
+			(void)strlcat(wbuf, " ", full_len + 1);
+		}
+		strlcat(wbuf, "+", full_len + 1);
+		strlcat(wbuf, controller, full_len + 1);
+	}
+	if (!wbuf)
+		return log_debug(true, "No controllers to delegate!");
+
+	ret = lxc_writeat(fd_dir, "cgroup.subtree_control", wbuf, strlen(wbuf));
+	if (ret < 0)
+		return log_error_errno(false, errno, "Failed to write \"%s\" to %s/cgroup.subtree_control", wbuf, cg);
+
+	return true;
+}
+
+/*
+ * systemd places us in say .../lxc-1.scope.  We create lxc-1.scope/init,
+ * move ourselves to there, then enable controllers in lxc-1.scope
+ */
+static bool move_and_delegate_unified(char *parent_cgroup)
+{
+	__do_free char *buf = NULL;
+	__do_close int fd_parent = -EBADF;
+	int ret;
+
+	fd_parent = open_at(-EBADF, parent_cgroup, O_DIRECTORY, 0, 0);
+	if (fd_parent < 0)
+		return syserror_ret(false, "Failed opening cgroup dir \"%s\"", parent_cgroup);
+
+	ret = mkdirat(fd_parent, "init", 0755);
+	if (ret < 0 && errno != EEXIST)
+		return syserror_ret(false, "Failed to create \"%d/init\" cgroup", fd_parent);
+
+	buf = read_file_at(fd_parent, "cgroup.procs", PROTECT_OPEN, 0);
+	if (!buf)
+		return false;
+
+	ret = lxc_writeat(fd_parent, "init/cgroup.procs", buf, strlen(buf));
+	if (ret)
+		return syserror_ret(false, "Failed to escape to cgroup \"init/cgroup.procs\"");
+
+	/* enable controllers in parent_cgroup */
+	return enable_controllers_delegation(fd_parent, parent_cgroup);
+}
+
+static int unpriv_systemd_create_scope(struct cgroup_ops *ops, struct lxc_conf *conf)
+{
+	__do_free char *full_scope_name = NULL;
+	__do_free char *fs_cg_path = NULL;
+	sd_event *event = NULL;
+	__attribute__((__cleanup__(sd_bus_unrefp))) sd_bus *bus = NULL; // free the bus before the names it references, just to be sure
+	struct sd_callback_data sd_data;
+	int idx = 0;
+	size_t len;
+	int r;
+
+	if (geteuid() == 0)
+		return log_info(SYSTEMD_SCOPE_UNSUPP, "Running privileged, not using a systemd unit");
+	// Pure_unified_layout() can't be used as that info is not yet setup.  At
+	// the same time, we don't want to calculate current cgroups until after
+	// we optionally enter a new systemd user scope.  So let's just do a quick
+	// check for pure unified cgroup system: single line /proc/self/cgroup with
+	// only index '0:'
+	if (!pure_unified_system())
+		return log_info(SYSTEMD_SCOPE_UNSUPP, "Not in unified layout, not using a systemd unit");
+
+	r = sd_bus_open_user(&bus);
+	if (r < 0)
+		return log_error(SYSTEMD_SCOPE_FAILED, "Failed to connect to user bus: %s", strerror(-r));
+
+	r = sd_bus_call_method_async(bus, NULL, DESTINATION, PATH, INTERFACE, "Subscribe", NULL, NULL, NULL);
+	if (r < 0)
+		return log_error(SYSTEMD_SCOPE_FAILED, "Failed to subscribe to signals: %s", strerror(-r));
+
+	sd_data.job_complete = false;
+	sd_data.scope_name = NULL;
+	r = sd_bus_match_signal(bus,
+		NULL, // no slot
+		DESTINATION, PATH, INTERFACE, "JobRemoved",
+		systemd_jobremoved_callback, &sd_data);
+	if (r < 0)
+		return log_error(SYSTEMD_SCOPE_FAILED, "Failed to register systemd event loop signal handler: %s", strerror(-r));
+
+	// NEXT: create and attach event
+	r = sd_event_new(&event);
+	if (r < 0)
+		return log_error(SYSTEMD_SCOPE_FAILED, "Failed allocating new event: %s\n", strerror(-r));
+	r = sd_bus_attach_event(bus, event, SD_EVENT_PRIORITY_NORMAL);
+	if (r < 0) {
+		// bus won't clean up event since the attach failed
+		sd_event_unrefp(&event);
+		return log_error(SYSTEMD_SCOPE_FAILED, "Failed attaching event: %s\n", strerror(-r));
+	}
+
+	// "lxc-" + (conf->name) + "-NN" + ".scope" + '\0'
+	len = STRLITERALLEN("lxc-") + strlen(conf->name) + 3 + STRLITERALLEN(".scope") + 1;
+	full_scope_name = malloc(len);
+	if (!full_scope_name)
+		return syserror("Out of memory");
+
+	do {
+		r = strnprintf(full_scope_name, len, "lxc-%s-%d.scope", conf->name, idx);
+		if (r < 0)
+			return log_error_errno(-1, errno, "Failed to build scope name for \"%s\"", conf->name);
+		sd_data.scope_name = full_scope_name;
+		if (start_scope(bus, &sd_data, event)) {
+			conf->cgroup_meta.systemd_scope = get_current_unified_cgroup();
+			if (!conf->cgroup_meta.systemd_scope)
+				return log_trace(SYSTEMD_SCOPE_FAILED, "Out of memory");
+			fs_cg_path = must_make_path("/sys/fs/cgroup", conf->cgroup_meta.systemd_scope, NULL);
+			if (!move_and_delegate_unified(fs_cg_path))
+				return log_error(SYSTEMD_SCOPE_FAILED, "Failed delegating the controllers to our cgroup");
+			return log_trace(SYSTEMD_SCOPE_SUCCESS, "Created systemd scope %s", full_scope_name);
+		}
+		idx++;
+	} while (idx < 99);
+
+	return SYSTEMD_SCOPE_FAILED; // failed, let's try old-school after all
+}
+#else /* !HAVE_LIBSYSTEMD */
+static int unpriv_systemd_create_scope(struct cgroup_ops *ops, struct lxc_conf *conf)
+{
+	TRACE("unpriv_systemd_create_scope: no systemd support");
+	return SYSTEMD_SCOPE_UNSUPP; // not supported
+}
+#endif /* HAVE_LIBSYSTEMD */
+
+// Return a duplicate of cgroup path @cg without leading /, so
+// that caller can own+free it and be certain it's not abspath.
+static char *cgroup_relpath(char *cg)
+{
+	char *p;
+
+	if (!cg || strequal(cg, "/"))
+		return NULL;
+	p = strdup(deabs(cg));
+	if (!p)
+		return ERR_PTR(-ENOMEM);
+
+	return p;
+}
+
+__cgfsng_ops static inline bool isulad_cgfsng_monitor_create(struct cgroup_ops *ops,
+						      struct lxc_handler *handler)
+{
+	return true;
+}
+
+static bool isulad_copy_parent_file(char *path, char *file)
+{
+	int ret;
+	int len = 0;
+	char *value = NULL;
+	char *current = NULL;
+	char *fpath = NULL;
+	char *lastslash = NULL;
+	char oldv;
+
+	fpath = must_make_path(path, file, NULL);
+	current = read_file(fpath);
+
+	if (current == NULL) {
+		SYSERROR("Failed to read file \"%s\"", fpath);
+		free(fpath);
+		return false;
+	}
+
+	if (strcmp(current, "\n") != 0) {
+		free(fpath);
+		free(current);
+		return true;
+	}
+
+	free(fpath);
+	free(current);
+
+	lastslash = strrchr(path, '/');
+	if (lastslash == NULL) {
+		ERROR("Failed to detect \"/\" in \"%s\"", path);
+		return false;
+	}
+	oldv = *lastslash;
+	*lastslash = '\0';
+	fpath = must_make_path(path, file, NULL);
+	*lastslash = oldv;
+	len = lxc_read_from_file(fpath, NULL, 0);
+	if (len <= 0)
+		goto on_error;
+
+	value = must_realloc(NULL, len + 1);
+	ret = lxc_read_from_file(fpath, value, len);
+	if (ret != len)
+		goto on_error;
+	free(fpath);
 
 	fpath = must_make_path(path, file, NULL);
 	ret = lxc_write_to_file(fpath, value, len, false, 0666);
@@ -926,8 +1064,8 @@ static bool create_path_for_hierarchy(struct hierarchy *h, char *cgname, int err
 		return false;
 	}
 
-	h->cgfd_con = lxc_open_dirfd(path);
-	if (h->cgfd_con < 0)
+	h->dfd_con = lxc_open_dirfd(path);
+	if (h->dfd_con < 0)
 		return log_error_errno(false, errno, "Failed to open %s", path);
 
 	if (h->path_con == NULL) {
@@ -1071,7 +1209,7 @@ static int chown_cgroup_wrapper(void *data)
 	uid_t nsuid = (arg->conf->root_nsuid_map != NULL) ? 0 : arg->conf->init_uid;
 	gid_t nsgid = (arg->conf->root_nsgid_map != NULL) ? 0 : arg->conf->init_gid;
 
-	if (!lxc_setgroups(0, NULL) && errno != EPERM)
+	if (!lxc_drop_groups() && errno != EPERM)
 		return log_error_errno(-1, errno, "Failed to setgroups(0, NULL)");
 
 	ret = setresgid(nsgid, nsgid, nsgid);
@@ -1089,7 +1227,10 @@ static int chown_cgroup_wrapper(void *data)
 		destuid = 0;
 
 	for (int i = 0; arg->hierarchies[i]; i++) {
-		int dirfd = arg->hierarchies[i]->cgfd_con;
+		int dirfd = arg->hierarchies[i]->dfd_con;
+
+		if (dirfd < 0)
+			return syserror_set(-EBADF, "Invalid cgroup file descriptor");
 
 		(void)fchowmodat(dirfd, "", destuid, nsgid, 0775);
 
@@ -1101,15 +1242,15 @@ static int chown_cgroup_wrapper(void *data)
 		 * files (which systemd in wily insists on doing).
 		 */
 
-		if (arg->hierarchies[i]->fs_type == CGROUP_SUPER_MAGIC)
+		if (arg->hierarchies[i]->fs_type == LEGACY_HIERARCHY)
 			(void)fchowmodat(dirfd, "tasks", destuid, nsgid, 0664);
 
 		(void)fchowmodat(dirfd, "cgroup.procs", destuid, nsgid, 0664);
 
-		if (arg->hierarchies[i]->fs_type != CGROUP2_SUPER_MAGIC)
+		if (arg->hierarchies[i]->fs_type != UNIFIED_HIERARCHY)
 			continue;
 
-		for (char **p = arg->hierarchies[i]->cgroup2_chown; p && *p; p++)
+		for (char **p = arg->hierarchies[i]->delegate; p && *p; p++)
 			(void)fchowmodat(dirfd, *p, destuid, nsgid, 0664);
 	}
 
@@ -1133,7 +1274,7 @@ __cgfsng_ops static bool isulad_cgfsng_chown(struct cgroup_ops *ops,
 	if (!conf)
 		return ret_set_errno(false, EINVAL);
 
-	if (lxc_list_empty(&conf->id_map))
+	if (list_empty(&conf->id_map))
 		return true;
 
 	wrap.origuid = geteuid();
@@ -1147,7 +1288,7 @@ __cgfsng_ops static bool isulad_cgfsng_chown(struct cgroup_ops *ops,
 	return true;
 }
 
-__cgfsng_ops void isulad_cgfsng_payload_finalize(struct cgroup_ops *ops)
+__cgfsng_ops static void isulad_cgfsng_finalize(struct cgroup_ops *ops)
 {
 	if (!ops)
 		return;
@@ -1164,15 +1305,33 @@ __cgfsng_ops void isulad_cgfsng_payload_finalize(struct cgroup_ops *ops)
 
 	for (int i = 0; ops->hierarchies[i]; i++) {
 		struct hierarchy *h = ops->hierarchies[i];
-		/*
-		 * we don't keep the fds for non-unified hierarchies around
-		 * mainly because we don't make use of them anymore after the
-		 * core cgroup setup is done but also because there are quite a
-		 * lot of them.
-		 */
-		if (!is_unified_hierarchy(h))
-			close_prot_errno_disarm(h->cgfd_con);
+
+		/* Close all monitor cgroup file descriptors. */
+		close_prot_errno_disarm(h->dfd_mon);
 	}
+	/* Close the cgroup root file descriptor. */
+	close_prot_errno_disarm(ops->dfd_mnt);
+
+	/*
+	 * The checking for freezer support should obviously be done at cgroup
+	 * initialization time but that doesn't work reliable. The freezer
+	 * controller has been demoted (rightly so) to a simple file located in
+	 * each non-root cgroup. At the time when the container is created we
+	 * might still be located in /sys/fs/cgroup and so checking for
+	 * cgroup.freeze won't tell us anything because this file doesn't exist
+	 * in the root cgroup. We could then iterate through /sys/fs/cgroup and
+	 * find an already existing cgroup and then check within that cgroup
+	 * for the existence of cgroup.freeze but that will only work on
+	 * systemd based hosts. Other init systems might not manage cgroups and
+	 * so no cgroup will exist. So we defer until we have created cgroups
+	 * for our container which means we check here.
+	 */
+        if (pure_unified_layout(ops) &&
+            !faccessat(ops->unified->dfd_con, "cgroup.freeze", F_OK,
+                       AT_SYMLINK_NOFOLLOW)) {
+		TRACE("Unified hierarchy supports freezer");
+		ops->unified->utilities |= FREEZER_CONTROLLER;
+        }
 }
 
 /* cgroup-full:* is done, no need to create subdirs */
@@ -1235,6 +1394,118 @@ static int cg_legacy_mount_controllers(int type, struct hierarchy *h,
 	return 0;
 }
 
+/* __cgroupfs_mount
+ *
+ * Mount cgroup hierarchies directly without using bind-mounts. The main
+ * uses-cases are mounting cgroup hierarchies in cgroup namespaces and mounting
+ * cgroups for the LXC_AUTO_CGROUP_FULL option.
+ */
+static int __cgroupfs_mount(int cgroup_automount_type, struct hierarchy *h,
+			    struct lxc_rootfs *rootfs, int dfd_mnt_cgroupfs,
+			    const char *hierarchy_mnt)
+{
+	__do_close int fd_fs = -EBADF;
+	unsigned int flags = 0;
+	char *fstype;
+	int ret;
+
+	if (dfd_mnt_cgroupfs < 0)
+		return ret_errno(EINVAL);
+
+	flags |= MOUNT_ATTR_NOSUID;
+	flags |= MOUNT_ATTR_NOEXEC;
+	flags |= MOUNT_ATTR_NODEV;
+	flags |= MOUNT_ATTR_RELATIME;
+
+	if ((cgroup_automount_type == LXC_AUTO_CGROUP_RO) ||
+	    (cgroup_automount_type == LXC_AUTO_CGROUP_FULL_RO) ||
+	    (cgroup_automount_type == LXC_AUTO_CGROUP2_RO))
+		flags |= MOUNT_ATTR_RDONLY;
+
+	if (is_unified_hierarchy(h))
+		fstype = "cgroup2";
+	else
+		fstype = "cgroup";
+
+	if (can_use_mount_api()) {
+		fd_fs = fs_prepare(fstype, -EBADF, "", 0, 0);
+		if (fd_fs < 0)
+			return log_error_errno(-errno, errno, "Failed to prepare filesystem context for %s", fstype);
+
+		if (!is_unified_hierarchy(h)) {
+			for (const char **it = (const char **)h->controllers; it && *it; it++) {
+				if (strnequal(*it, "name=", STRLITERALLEN("name=")))
+					ret = fs_set_property(fd_fs, "name", *it + STRLITERALLEN("name="));
+				else
+					ret = fs_set_property(fd_fs, *it, "");
+				if (ret < 0)
+					return log_error_errno(-errno, errno, "Failed to add %s controller to cgroup filesystem context %d(dev)", *it, fd_fs);
+			}
+		}
+
+		ret = fs_attach(fd_fs, dfd_mnt_cgroupfs, hierarchy_mnt,
+				PROTECT_OPATH_DIRECTORY, PROTECT_LOOKUP_BENEATH,
+				flags);
+	} else {
+		__do_free char *controllers = NULL, *target = NULL;
+		unsigned int old_flags = 0;
+		const char *rootfs_mnt;
+
+		if (!is_unified_hierarchy(h)) {
+			controllers = lxc_string_join(",", (const char **)h->controllers, false);
+			if (!controllers)
+				return ret_errno(ENOMEM);
+		}
+
+		rootfs_mnt = get_rootfs_mnt(rootfs);
+		ret = mnt_attributes_old(flags, &old_flags);
+		if (ret)
+			return log_error_errno(-EINVAL, EINVAL, "Unsupported mount properties specified");
+
+		target = must_make_path(rootfs_mnt, DEFAULT_CGROUP_MOUNTPOINT, hierarchy_mnt, NULL);
+#ifdef HAVE_ISULAD
+		ret = safe_mount(NULL, target, fstype, old_flags, controllers, rootfs_mnt, NULL);
+#else
+		ret = safe_mount(NULL, target, fstype, old_flags, controllers, rootfs_mnt);
+#endif
+	}
+	if (ret < 0)
+		return log_error_errno(ret, errno, "Failed to mount %s filesystem onto %d(%s)",
+				       fstype, dfd_mnt_cgroupfs, maybe_empty(hierarchy_mnt));
+
+	DEBUG("Mounted cgroup filesystem %s onto %d(%s)",
+	      fstype, dfd_mnt_cgroupfs, maybe_empty(hierarchy_mnt));
+	return 0;
+}
+
+static inline int cgroupfs_mount(int cgroup_automount_type, struct hierarchy *h,
+				 struct lxc_rootfs *rootfs,
+				 int dfd_mnt_cgroupfs, const char *hierarchy_mnt)
+{
+	return __cgroupfs_mount(cgroup_automount_type, h, rootfs,
+				dfd_mnt_cgroupfs, hierarchy_mnt);
+}
+
+static inline int cgroupfs_bind_mount(int cgroup_automount_type, struct hierarchy *h,
+				      struct lxc_rootfs *rootfs,
+				      int dfd_mnt_cgroupfs,
+				      const char *hierarchy_mnt)
+{
+	switch (cgroup_automount_type) {
+	case LXC_AUTO_CGROUP_FULL_RO:
+		break;
+	case LXC_AUTO_CGROUP_FULL_RW:
+		break;
+	case LXC_AUTO_CGROUP_FULL_MIXED:
+		break;
+	default:
+		return 0;
+	}
+
+	return __cgroupfs_mount(cgroup_automount_type, h, rootfs,
+				dfd_mnt_cgroupfs, hierarchy_mnt);
+}
+
 /* __cg_mount_direct
  *
  * Mount cgroup hierarchies directly without using bind-mounts. The main
@@ -1289,139 +1560,300 @@ static inline int cg_mount_cgroup_full(int type, struct hierarchy *h,
 }
 
 __cgfsng_ops static bool isulad_cgfsng_mount(struct cgroup_ops *ops,
-                                      struct lxc_handler *handler,
-                                      const char *root, int type)
-{
-	int i, ret;
-	char *tmpfspath = NULL;
-	char *systemdpath = NULL;
-	char *unifiedpath = NULL;
-	bool has_cgns = false, retval = false, wants_force_mount = false;
+				      struct lxc_handler *handler, int cg_flags)
+{
+	__do_close int dfd_mnt_tmpfs = -EBADF, fd_fs = -EBADF;
+	__do_free char *cgroup_root = NULL;
+	int cgroup_automount_type;
+	bool in_cgroup_ns = false, wants_force_mount = false;
+	struct lxc_conf *conf = handler->conf;
+	struct lxc_rootfs *rootfs = &conf->rootfs;
+	const char *rootfs_mnt = get_rootfs_mnt(rootfs);
+	int ret;
+#ifdef HAVE_ISULAD
 	char **merged = NULL;
+	__do_free char *systemdpath = NULL;
+	__do_free char *unifiedpath = NULL;
+#endif
+
+	if (!ops)
+		return ret_set_errno(false, ENOENT);
 
-	if ((type & LXC_AUTO_CGROUP_MASK) == 0)
+	if (!ops->hierarchies)
 		return true;
 
-	if (type & LXC_AUTO_CGROUP_FORCE) {
-		type &= ~LXC_AUTO_CGROUP_FORCE;
+	if (!conf)
+		return ret_set_errno(false, EINVAL);
+
+	if ((cg_flags & LXC_AUTO_CGROUP_MASK) == 0)
+		return log_trace(true, "No cgroup mounts requested");
+
+	if (cg_flags & LXC_AUTO_CGROUP_FORCE) {
+		cg_flags &= ~LXC_AUTO_CGROUP_FORCE;
 		wants_force_mount = true;
 	}
 
+	switch (cg_flags) {
+	case LXC_AUTO_CGROUP_RO:
+		TRACE("Read-only cgroup mounts requested");
+		break;
+	case LXC_AUTO_CGROUP_RW:
+		TRACE("Read-write cgroup mounts requested");
+		break;
+	case LXC_AUTO_CGROUP_MIXED:
+		TRACE("Mixed cgroup mounts requested");
+		break;
+	case LXC_AUTO_CGROUP_FULL_RO:
+		TRACE("Full read-only cgroup mounts requested");
+		break;
+	case LXC_AUTO_CGROUP_FULL_RW:
+		TRACE("Full read-write cgroup mounts requested");
+		break;
+	case LXC_AUTO_CGROUP_FULL_MIXED:
+		TRACE("Full mixed cgroup mounts requested");
+		break;
+	case LXC_AUTO_CGROUP2_RW:
+		TRACE("Read-write cgroup2 mount requested");
+		break;
+	case LXC_AUTO_CGROUP2_RO:
+		TRACE("Read-only cgroup2 mount requested");
+		break;
+	default:
+		return log_error_errno(false, EINVAL, "Invalid cgroup mount options specified");
+	}
+	cgroup_automount_type = cg_flags;
+
 	if (!wants_force_mount) {
-		if (!lxc_list_empty(&handler->conf->keepcaps))
-			wants_force_mount = !in_caplist(CAP_SYS_ADMIN, &handler->conf->keepcaps);
-		else
-			wants_force_mount = in_caplist(CAP_SYS_ADMIN, &handler->conf->caps);
+		wants_force_mount = !lxc_wants_cap(CAP_SYS_ADMIN, conf);
+
+		/*
+		 * Most recent distro versions currently have init system that
+		 * do support cgroup2 but do not mount it by default unless
+		 * explicitly told so even if the host is cgroup2 only. That
+		 * means they often will fail to boot. Fix this by pre-mounting
+		 * cgroup2 by default. We will likely need to be doing this a
+		 * few years until all distros have switched over to cgroup2 at
+		 * which point we can safely assume that their init systems
+		 * will mount it themselves.
+		 */
+		if (pure_unified_layout(ops))
+			wants_force_mount = true;
 	}
 
-	has_cgns = cgns_supported();
-	if (has_cgns && !wants_force_mount)
-		return true;
+	if (cgns_supported() && container_uses_namespace(handler, CLONE_NEWCGROUP))
+		in_cgroup_ns = true;
 
-	if (type == LXC_AUTO_CGROUP_NOSPEC)
-		type = LXC_AUTO_CGROUP_MIXED;
-	else if (type == LXC_AUTO_CGROUP_FULL_NOSPEC)
-		type = LXC_AUTO_CGROUP_FULL_MIXED;
+	if (in_cgroup_ns && !wants_force_mount)
+		return log_trace(true, "Mounting cgroups not requested or needed");
 
-	/* Mount tmpfs */
-	tmpfspath = must_make_path(root, "/sys/fs/cgroup", NULL);
-	if (mkdir_p(tmpfspath, 0755) < 0) {
-		ERROR("Failed to create directory: %s", tmpfspath);
-		goto on_error;
+	/* This is really the codepath that we want. */
+	if (pure_unified_layout(ops) ||
+	    (cgroup_automount_type == LXC_AUTO_CGROUP2_RW) ||
+	    (cgroup_automount_type == LXC_AUTO_CGROUP2_RO)) {
+		__do_close int dfd_mnt_unified = -EBADF;
+
+		if (!ops->unified)
+			return log_error_errno(false, EINVAL, "No unified cgroup hierarchy mounted on the host");
+
+		dfd_mnt_unified = open_at(rootfs->dfd_mnt, DEFAULT_CGROUP_MOUNTPOINT_RELATIVE,
+					  PROTECT_OPATH_DIRECTORY, PROTECT_LOOKUP_BENEATH_XDEV, 0);
+		if (dfd_mnt_unified < 0)
+			return syserror_ret(false, "Failed to open %d(%s)",
+					    rootfs->dfd_mnt, DEFAULT_CGROUP_MOUNTPOINT_RELATIVE);
+		/*
+		 * If cgroup namespaces are supported but the container will
+		 * not have CAP_SYS_ADMIN after it has started we need to mount
+		 * the cgroups manually.
+		 *
+		 * Note that here we know that wants_force_mount is true.
+		 * Otherwise we would've returned early above.
+		 */
+		if (in_cgroup_ns) {
+			/*
+			 *  1. cgroup:rw:force    -> Mount the cgroup2 filesystem.
+			 *  2. cgroup:ro:force    -> Mount the cgroup2 filesystem read-only.
+			 *  3. cgroup:mixed:force -> See comment above how this
+			 *                           does not apply so
+			 *                           cgroup:mixed is equal to
+			 *                           cgroup:rw when cgroup
+			 *                           namespaces are supported.
+
+			 *  4. cgroup:rw    -> No-op; init system responsible for mounting.
+			 *  5. cgroup:ro    -> No-op; init system responsible for mounting.
+			 *  6. cgroup:mixed -> No-op; init system responsible for mounting.
+                         *
+			 *  7. cgroup-full:rw    -> Not supported.
+			 *  8. cgroup-full:ro    -> Not supported.
+			 *  9. cgroup-full:mixed -> Not supported.
+
+			 * 10. cgroup-full:rw:force    -> Not supported.
+			 * 11. cgroup-full:ro:force    -> Not supported.
+			 * 12. cgroup-full:mixed:force -> Not supported.
+			 *
+			 * 13. cgroup2		-> No-op; init system responsible for mounting.
+			 * 14. cgroup2:ro	-> No-op; init system responsible for mounting.
+			 * 15. cgroup2:force	-> Mount the cgroup2 filesystem read-write
+			 * 16. cgroup2:ro:force	-> Mount the cgroup2 filesystem read-only
+			 */
+			ret = cgroupfs_mount(cgroup_automount_type, ops->unified, rootfs, dfd_mnt_unified, "");
+			if (ret < 0)
+				return syserror_ret(false, "Failed to force mount cgroup filesystem in cgroup namespace");
+
+			return log_trace(true, "Force mounted cgroup filesystem in new cgroup namespace");
+		} else {
+			/*
+			 * Either no cgroup namespace supported (highly
+			 * unlikely unless we're dealing with a Frankenkernel.
+			 * Or the user requested to keep the cgroup namespace
+			 * of the host or another container.
+			 */
+			errno = EOPNOTSUPP;
+			if (wants_force_mount)
+				SYSWARN("Force-mounting the unified cgroup hierarchy without cgroup namespace support is currently not supported");
+			else
+				SYSWARN("Mounting the unified cgroup hierarchy without cgroup namespace support is currently not supported");
+		}
+
+		return syserror_ret(false, "Failed to mount cgroups");
 	}
 
-        if (ops->cgroup_layout == CGROUP_LAYOUT_UNIFIED) {
-                if (has_cgns && wants_force_mount) {
-                        /*
-                         * If cgroup namespaces are supported but the container
-                         * will not have CAP_SYS_ADMIN after it has started we
-                         * need to mount the cgroups manually.
-                         */
-                        return cg_mount_in_cgroup_namespace(type, ops->unified, tmpfspath) == 0;
-                }
+	/*
+	 * Mount a tmpfs over DEFAULT_CGROUP_MOUNTPOINT. Note that we're
+	 * relying on RESOLVE_BENEATH so we need to skip the leading "/" in the
+	 * DEFAULT_CGROUP_MOUNTPOINT define.
+	 */
+	if (can_use_mount_api()) {
+		fd_fs = fs_prepare("tmpfs", -EBADF, "", 0, 0);
+		if (fd_fs < 0)
+			return log_error_errno(false, errno, "Failed to create new filesystem context for tmpfs");
 
-                return cg_mount_cgroup_full(type, ops->unified, tmpfspath) == 0;
-        }
+		ret = fs_set_property(fd_fs, "mode", "0755");
+		if (ret < 0)
+			return log_error_errno(false, errno, "Failed to mount tmpfs onto %d(dev)", fd_fs);
+
+		ret = fs_set_property(fd_fs, "size", "10240k");
+		if (ret < 0)
+			return log_error_errno(false, errno, "Failed to mount tmpfs onto %d(dev)", fd_fs);
 
-	ret = safe_mount(NULL, tmpfspath, "tmpfs",
-	                 MS_NOSUID | MS_NODEV | MS_NOEXEC | MS_RELATIME,
-	                 "size=10240k,mode=755", root, handler->conf->lsm_se_mount_context);
+		ret = fs_attach(fd_fs, rootfs->dfd_mnt, DEFAULT_CGROUP_MOUNTPOINT_RELATIVE,
+				PROTECT_OPATH_DIRECTORY, PROTECT_LOOKUP_BENEATH_XDEV,
+				MOUNT_ATTR_NOSUID | MOUNT_ATTR_NODEV |
+				MOUNT_ATTR_NOEXEC | MOUNT_ATTR_RELATIME);
+	} else {
+		cgroup_root = must_make_path(rootfs_mnt, DEFAULT_CGROUP_MOUNTPOINT, NULL);
+		ret = safe_mount(NULL, cgroup_root, "tmpfs",
+				 MS_NOSUID | MS_NODEV | MS_NOEXEC | MS_RELATIME,
+				 "size=10240k,mode=755", rootfs_mnt, handler->conf->rootfs.lsm_se_mount_context);
+	}
 	if (ret < 0)
-		goto on_error;
+		return log_error_errno(false, errno, "Failed to mount tmpfs on %s",
+				       DEFAULT_CGROUP_MOUNTPOINT_RELATIVE);
 
-	for (i = 0; ops->hierarchies[i]; i++) {
-		char *controllerpath = NULL;
-		char *path2 = NULL;
-		struct hierarchy *h = ops->hierarchies[i];
-		char *controller = strrchr(h->at_mnt, '/');
+	dfd_mnt_tmpfs = open_at(rootfs->dfd_mnt, DEFAULT_CGROUP_MOUNTPOINT_RELATIVE,
+				PROTECT_OPATH_DIRECTORY, PROTECT_LOOKUP_BENEATH_XDEV, 0);
+	if (dfd_mnt_tmpfs < 0)
+		return syserror_ret(false, "Failed to open %d(%s)",
+				    rootfs->dfd_mnt, DEFAULT_CGROUP_MOUNTPOINT_RELATIVE);
 
-		if (!controller)
-			continue;
-		controller++;
+	for (int i = 0; ops->hierarchies[i]; i++) {
+		__do_free char *hierarchy_mnt = NULL, *path2 = NULL;
+		struct hierarchy *h = ops->hierarchies[i];
 
+#ifdef HAVE_ISULAD
 		// isulad: symlink subcgroup
-		if (strchr(controller, ',') != NULL) {
+		if (strchr(h->at_mnt, ',') != NULL) {
 			int pret;
-			pret = lxc_append_string(&merged, controller);
+			pret = lxc_append_string(&merged, h->at_mnt);
 			if (pret < 0)
-				goto on_error;
-		}
-
-		controllerpath = must_make_path(tmpfspath, controller, NULL);
-		if (dir_exists(controllerpath)) {
-			free(controllerpath);
-			continue;
+				return false;
 		}
+#endif
 
-		ret = mkdir(controllerpath, 0755);
+		ret = mkdirat(dfd_mnt_tmpfs, h->at_mnt, 0000);
+#ifdef HAVE_ISULAD
 		if (ret < 0) {
-			SYSERROR("Error creating cgroup path: %s", controllerpath);
-			free(controllerpath);
-			goto on_error;
+			lxc_free_array((void **)merged, free);
+			return syserror_ret(false, "Failed to create cgroup at_mnt %d(%s)", dfd_mnt_tmpfs, h->at_mnt);
 		}
+#else
+		if (ret < 0)
+			return syserror_ret(false, "Failed to create cgroup at_mnt %d(%s)", dfd_mnt_tmpfs, h->at_mnt);
+#endif
 
-		if (has_cgns && wants_force_mount) {
-			/* If cgroup namespaces are supported but the container
+		if (in_cgroup_ns && wants_force_mount) {
+			/*
+			 * If cgroup namespaces are supported but the container
 			 * will not have CAP_SYS_ADMIN after it has started we
 			 * need to mount the cgroups manually.
 			 */
-			ret = cg_mount_in_cgroup_namespace(type, h, controllerpath);
-			free(controllerpath);
+			ret = cgroupfs_mount(cgroup_automount_type, h, rootfs,
+					     dfd_mnt_tmpfs, h->at_mnt);
+#ifdef HAVE_ISULAD
+			if (ret < 0) {
+				lxc_free_array((void **)merged, free);
+				return false;
+			}
+#else
 			if (ret < 0)
-				goto on_error;
-
+				return false;
+#endif
 			continue;
 		}
 
-		ret = cg_mount_cgroup_full(type, h, controllerpath);
+		/* Here is where the ancient kernel section begins. */
+		ret = cgroupfs_bind_mount(cgroup_automount_type, h, rootfs,
+					  dfd_mnt_tmpfs, h->at_mnt);
+#ifdef HAVE_ISULAD
 		if (ret < 0) {
-			free(controllerpath);
-			goto on_error;
+			lxc_free_array((void **)merged, free);
+			return false;
 		}
+#else
+		if (ret < 0)
+			return false;
+#endif
 
-		if (!cg_mount_needs_subdirs(type)) {
-			free(controllerpath);
+		if (!cg_mount_needs_subdirs(cgroup_automount_type))
 			continue;
-		}
 
+		if (!cgroup_root)
+			cgroup_root = must_make_path(rootfs_mnt, DEFAULT_CGROUP_MOUNTPOINT, NULL);
+
+		hierarchy_mnt = must_make_path(cgroup_root, h->at_mnt, NULL);
+#ifdef HAVE_ISULAD
 		// isulad: ignore ops->container_cgroup so we will not see directory lxc after /sys/fs/cgroup/xxx in container,
-		// isulad: ignore h->at_base so we will not see subgroup of /sys/fs/cgroup/xxx/subgroup in container
-		path2 = must_make_path(controllerpath, NULL);
+		// isulad: ignore h->container_base_path so we will not see subgroup of /sys/fs/cgroup/xxx/subgroup in container
+		path2 = must_make_path(h->at_mnt, NULL);
+#else
+		path2 = must_make_path(hierarchy_mnt, h->at_base,
+				       ops->container_cgroup, NULL);
+#endif
 		ret = mkdir_p(path2, 0755);
-		if (ret < 0) {
-			free(controllerpath);
-			free(path2);
-			goto on_error;
+#ifdef HAVE_ISULAD
+		if (ret < 0 && (errno != EEXIST)) {
+			lxc_free_array((void **)merged, free);
+			return false;
 		}
+#else
+		if (ret < 0 && (errno != EEXIST))
+			return false;
+#endif
 
-		ret = cg_legacy_mount_controllers(type, h, controllerpath,
-		                                  path2, ops->container_cgroup);
-		free(controllerpath);
-		free(path2);
+		ret = cg_legacy_mount_controllers(cgroup_automount_type, h,
+						  hierarchy_mnt, path2,
+						  ops->container_cgroup);
+#ifdef HAVE_ISULAD
+		if (ret < 0) {
+			lxc_free_array((void **)merged, free);
+			return false;
+		}
+#else
 		if (ret < 0)
-			goto on_error;
+			return false;
+#endif
 	}
 
+#ifdef HAVE_ISULAD
 	// isulad: symlink subcgroup
 	if (merged) {
 		char **mc = NULL;
@@ -1431,13 +1863,14 @@ __cgfsng_ops static bool isulad_cgfsng_mount(struct cgroup_ops *ops,
 			lxc_iterate_parts(token, copy, ",") {
 				int mret;
 				char *link;
-				link = must_make_path(tmpfspath, token, NULL);
+				link = must_make_path(cgroup_root, token, NULL);
 				mret = symlink(*mc, link);
 				if (mret < 0 && errno != EEXIST) {
 					SYSERROR("Failed to create link %s for target %s", link, *mc);
 					free(copy);
 					free(link);
-					goto on_error;
+					lxc_free_array((void **)merged, free);
+					return false;
 				}
 				free(link);
 			}
@@ -1445,59 +1878,49 @@ __cgfsng_ops static bool isulad_cgfsng_mount(struct cgroup_ops *ops,
 		}
 	}
 
-
 	// isulad: remount /sys/fs/cgroup to readonly
-	if (type == LXC_AUTO_CGROUP_FULL_RO || type == LXC_AUTO_CGROUP_RO) {
-		ret = mount(tmpfspath, tmpfspath, "bind",
+	if (cg_flags == LXC_AUTO_CGROUP_FULL_RO || cg_flags == LXC_AUTO_CGROUP_RO) {
+		ret = mount(cgroup_root, cgroup_root, "bind",
 		            MS_NOSUID|MS_NODEV|MS_NOEXEC|MS_RELATIME|MS_RDONLY|MS_BIND|MS_REMOUNT, NULL);
 		if (ret < 0) {
 			SYSERROR("Failed to remount /sys/fs/cgroup.");
-			goto on_error;
+			lxc_free_array((void **)merged, free);
+			return false;
 		}
 	}
 
 	// isulad: remount /sys/fs/cgroup/systemd to readwrite for system container
 	if (handler->conf->systemd != NULL && strcmp(handler->conf->systemd, "true") == 0)
 	{
-		unifiedpath = must_make_path(root, "/sys/fs/cgroup/unified", NULL);
+		unifiedpath = must_make_path(get_rootfs_mnt(rootfs), "/sys/fs/cgroup/unified", NULL);
 		if (dir_exists(unifiedpath))
 		{
 			ret = umount2(unifiedpath, MNT_DETACH);
 			if (ret < 0)
 			{
 				SYSERROR("Failed to umount /sys/fs/cgroup/unified.");
-				goto on_error;
+				lxc_free_array((void **)merged, free);
+				return false;
 			}
 		}
 
-		systemdpath = must_make_path(root, "/sys/fs/cgroup/systemd", NULL);
+		systemdpath = must_make_path(get_rootfs_mnt(rootfs), "/sys/fs/cgroup/systemd", NULL);
 		ret = mount(systemdpath, systemdpath, "bind",
 					MS_NOSUID | MS_NODEV | MS_NOEXEC | MS_RELATIME | MS_BIND | MS_REMOUNT, NULL);
 		if (ret < 0)
 		{
 			SYSERROR("Failed to remount /sys/fs/cgroup/systemd.");
-			goto on_error;
+			lxc_free_array((void **)merged, free);
+			return false;
 		}
 	}
+#endif
 
-	retval = true;
-
-on_error:
-	free(tmpfspath);
-	if (systemdpath != NULL)
-	{
-		free(systemdpath);
-	}
-	if (unifiedpath != NULL)
-	{
-		free(unifiedpath);
-	}
-	lxc_free_array((void **)merged, free);
-	return retval;
+	return true;
 }
 
 /* Only root needs to escape to the cgroup of its init. */
-__cgfsng_ops static bool isulad_cgfsng_escape(const struct cgroup_ops *ops,
+__cgfsng_ops static bool isulad_cgfsng_criu_escape(const struct cgroup_ops *ops,
 				       struct lxc_conf *conf)
 {
 	if (!ops)
@@ -1528,7 +1951,7 @@ __cgfsng_ops static bool isulad_cgfsng_escape(const struct cgroup_ops *ops,
 	return true;
 }
 
-__cgfsng_ops static int isulad_cgfsng_num_hierarchies(struct cgroup_ops *ops)
+__cgfsng_ops static int isulad_cgfsng_criu_num_hierarchies(struct cgroup_ops *ops)
 {
 	int i = 0;
 
@@ -1544,7 +1967,7 @@ __cgfsng_ops static int isulad_cgfsng_num_hierarchies(struct cgroup_ops *ops)
 	return i;
 }
 
-__cgfsng_ops static bool isulad_cgfsng_get_hierarchies(struct cgroup_ops *ops, int n,
+__cgfsng_ops static bool isulad_cgfsng_criu_get_hierarchies(struct cgroup_ops *ops, int n,
 						char ***out)
 {
 	int i;
@@ -1578,7 +2001,7 @@ static bool cg_legacy_freeze(struct cgroup_ops *ops)
 }
 
 static int freezer_cgroup_events_cb(int fd, uint32_t events, void *cbdata,
-				    struct lxc_epoll_descr *descr)
+				    struct lxc_async_descr *descr)
 {
 	__do_close int duped_fd = -EBADF;
 	__do_free char *line = NULL;
@@ -1614,9 +2037,9 @@ static int freezer_cgroup_events_cb(int fd, uint32_t events, void *cbdata,
 static int cg_unified_freeze(struct cgroup_ops *ops, int timeout)
 {
 	__do_close int fd = -EBADF;
-	call_cleaner(lxc_mainloop_close) struct lxc_epoll_descr *descr_ptr = NULL;
+	call_cleaner(lxc_mainloop_close) struct lxc_async_descr *descr_ptr = NULL;
 	int ret;
-	struct lxc_epoll_descr descr;
+	struct lxc_async_descr descr;
 	struct hierarchy *h;
 
 	h = ops->unified;
@@ -1641,7 +2064,8 @@ static int cg_unified_freeze(struct cgroup_ops *ops, int timeout)
 		/* automatically cleaned up now */
 		descr_ptr = &descr;
 
-		ret = lxc_mainloop_add_handler(&descr, fd, freezer_cgroup_events_cb, INT_TO_PTR((int){1}));
+		ret = lxc_mainloop_add_handler(&descr, fd, freezer_cgroup_events_cb, default_cleanup_handler,
+									   INT_TO_PTR((int){1}), "freezer_cgroup_events");
 		if (ret < 0)
 			return log_error_errno(-1, errno, "Failed to add cgroup.events fd handler to mainloop");
 	}
@@ -1682,9 +2106,9 @@ static int cg_legacy_unfreeze(struct cgroup_ops *ops)
 static int cg_unified_unfreeze(struct cgroup_ops *ops, int timeout)
 {
 	__do_close int fd = -EBADF;
-	call_cleaner(lxc_mainloop_close)struct lxc_epoll_descr *descr_ptr = NULL;
+	call_cleaner(lxc_mainloop_close)struct lxc_async_descr *descr_ptr = NULL;
 	int ret;
-	struct lxc_epoll_descr descr;
+	struct lxc_async_descr descr;
 	struct hierarchy *h;
 
 	h = ops->unified;
@@ -1709,7 +2133,8 @@ static int cg_unified_unfreeze(struct cgroup_ops *ops, int timeout)
 		/* automatically cleaned up now */
 		descr_ptr = &descr;
 
-		ret = lxc_mainloop_add_handler(&descr, fd, freezer_cgroup_events_cb, INT_TO_PTR((int){0}));
+		ret = lxc_mainloop_add_handler(&descr, fd, freezer_cgroup_events_cb, default_cleanup_handler,
+									   INT_TO_PTR((int){0}), "freezer_cgroup_events");
 		if (ret < 0)
 			return log_error_errno(-1, errno, "Failed to add cgroup.events fd handler to mainloop");
 	}
@@ -1816,7 +2241,7 @@ static int cgroup_attach_leaf(const struct lxc_conf *conf, int unified_fd, pid_t
 		 * that a short write would cause a buffer overrun. So be on
 		 * the safe side.
 		 */
-		if (ret < STRLITERALLEN(".lxc-/cgroup.procs"))
+		if ((size_t)ret < STRLITERALLEN(".lxc-/cgroup.procs"))
 			return log_error_errno(-EINVAL, EINVAL, "Unexpected short write would cause buffer-overrun");
 
 		slash = &attach_cgroup[ret] - STRLITERALLEN("/cgroup.procs");
@@ -1848,7 +2273,7 @@ static int cgroup_attach_leaf(const struct lxc_conf *conf, int unified_fd, pid_t
 }
 
 static int cgroup_attach_create_leaf(const struct lxc_conf *conf,
-				     int unified_fd, int *sk_fd)
+				     int unified_fd, int *sk_fd, bool unprivileged)
 {
 	__do_close int sk = *sk_fd, target_fd0 = -EBADF, target_fd1 = -EBADF;
 	int target_fds[2];
@@ -1857,73 +2282,116 @@ static int cgroup_attach_create_leaf(const struct lxc_conf *conf,
 	/* Create leaf cgroup. */
 	ret = mkdirat(unified_fd, ".lxc", 0755);
 	if (ret < 0 && errno != EEXIST)
-		return log_error_errno(-1, errno, "Failed to create leaf cgroup \".lxc\"");
+		return syserror("Failed to create leaf cgroup \".lxc\"");
 
-	target_fd0 = openat(unified_fd, ".lxc/cgroup.procs", O_WRONLY | O_CLOEXEC | O_NOFOLLOW);
-	if (target_fd0 < 0)
-		return log_error_errno(-errno, errno, "Failed to open \".lxc/cgroup.procs\"");
-	target_fds[0] = target_fd0;
+	if (unprivileged) {
+		target_fd0 = open_at(unified_fd, ".lxc/cgroup.procs", PROTECT_OPEN_W, PROTECT_LOOKUP_BENEATH, 0);
+		if (target_fd0 < 0)
+			return syserror("Failed to open \".lxc/cgroup.procs\"");
+		target_fds[0] = target_fd0;
 
-	target_fd1 = openat(unified_fd, "cgroup.procs", O_WRONLY | O_CLOEXEC | O_NOFOLLOW);
-	if (target_fd1 < 0)
-		return log_error_errno(-errno, errno, "Failed to open \".lxc/cgroup.procs\"");
-	target_fds[1] = target_fd1;
+		target_fd1 = open_at(unified_fd, "cgroup.procs", PROTECT_OPEN_W, PROTECT_LOOKUP_BENEATH, 0);
+		if (target_fd1 < 0)
+			return syserror("Failed to open \".lxc/cgroup.procs\"");
+		target_fds[1] = target_fd1;
 
-	ret = lxc_abstract_unix_send_fds(sk, target_fds, 2, NULL, 0);
-	if (ret <= 0)
-		return log_error_errno(-errno, errno, "Failed to send \".lxc/cgroup.procs\" fds %d and %d",
-				       target_fd0, target_fd1);
+		ret = lxc_abstract_unix_send_fds(sk, target_fds, 2, NULL, 0);
+		if (ret <= 0)
+			return syserror("Failed to send \".lxc/cgroup.procs\" fds %d and %d",
+					target_fd0, target_fd1);
 
-	return log_debug(0, "Sent target cgroup fds %d and %d", target_fd0, target_fd1);
+		TRACE("Sent cgroup file descriptors %d and %d", target_fd0, target_fd1);
+	} else {
+		ret = lxc_abstract_unix_send_credential(sk, NULL, 0);
+		if (ret < 0)
+			return syserror("Failed to inform parent that we are done setting up mounts");
+
+		TRACE("Informed parent process that cgroup has been created");
+	}
+
+	return 0;
 }
 
 static int cgroup_attach_move_into_leaf(const struct lxc_conf *conf,
-					int *sk_fd, pid_t pid)
+					const char *lxcpath,
+					int unified_fd, int *sk_fd, pid_t pid,
+					bool unprivileged)
 {
 	__do_close int sk = *sk_fd, target_fd0 = -EBADF, target_fd1 = -EBADF;
-	int target_fds[2];
 	char pidstr[INTTYPE_TO_STRLEN(int64_t) + 1];
 	size_t pidstr_len;
+#if HAVE_LIBSYSTEMD
+	__do_free char *scope = NULL;
+#endif
 	ssize_t ret;
 
-	ret = lxc_abstract_unix_recv_fds(sk, target_fds, 2, NULL, 0);
-	if (ret <= 0)
-		return log_error_errno(-1, errno, "Failed to receive target cgroup fd");
-	target_fd0 = target_fds[0];
-	target_fd1 = target_fds[1];
+#if HAVE_LIBSYSTEMD
+	scope = lxc_cmd_get_systemd_scope(conf->name, lxcpath);
+	if (scope) {
+		TRACE("%s:%s is running under systemd-created scope '%s'.  Attaching...", lxcpath, conf->name, scope);
+		if (enter_scope(scope, pid))
+			TRACE("Successfully entered scope '%s'", scope);
+		else
+			ERROR("Failed entering scope '%s'", scope);
+	} else {
+		TRACE("%s:%s is not running under a systemd-created scope", lxcpath, conf->name);
+	}
+#endif
+	if (unprivileged) {
+		ret = lxc_abstract_unix_recv_two_fds(sk, &target_fd0, &target_fd1);
+		if (ret < 0)
+			return log_error_errno(-1, errno, "Failed to receive target cgroup fd");
+	} else {
+		ret = lxc_abstract_unix_rcv_credential(sk, NULL, 0);
+		if (ret < 0)
+			return syserror("Failed to receive notification from parent process");
+
+		TRACE("Child process informed us that cgroup has been created");
+
+		target_fd0 = open_at(unified_fd, ".lxc/cgroup.procs", PROTECT_OPEN_W, PROTECT_LOOKUP_BENEATH, 0);
+		if (target_fd0 < 0)
+			return syserror("Failed to open \".lxc/cgroup.procs\"");
+
+		target_fd1 = open_at(unified_fd, "cgroup.procs", PROTECT_OPEN_W, PROTECT_LOOKUP_BENEATH, 0);
+		if (target_fd1 < 0)
+			return syserror("Failed to open \".lxc/cgroup.procs\"");
+
+		TRACE("Opened target cgroup file descriptors %d and %d", target_fd0, target_fd1);
+	}
 
 	pidstr_len = sprintf(pidstr, INT64_FMT, (int64_t)pid);
 
 	ret = lxc_write_nointr(target_fd0, pidstr, pidstr_len);
-	if (ret > 0 && ret == pidstr_len)
+	if (ret > 0 && (size_t)ret == pidstr_len)
 		return log_debug(0, "Moved process into target cgroup via fd %d", target_fd0);
 
 	ret = lxc_write_nointr(target_fd1, pidstr, pidstr_len);
-	if (ret > 0 && ret == pidstr_len)
+	if (ret > 0 && (size_t)ret == pidstr_len)
 		return log_debug(0, "Moved process into target cgroup via fd %d", target_fd1);
 
-	return log_debug_errno(-1, errno, "Failed to move process into target cgroup via fd %d and %d",
-			       target_fd0, target_fd1);
+	return syserror("Failed to move process into target cgroup via fd %d and %d", target_fd0, target_fd1);
 }
 
 struct userns_exec_unified_attach_data {
 	const struct lxc_conf *conf;
+	const char *lxcpath;
 	int unified_fd;
 	int sk_pair[2];
 	pid_t pid;
+	bool unprivileged;
 };
 
 static int cgroup_unified_attach_child_wrapper(void *data)
 {
 	struct userns_exec_unified_attach_data *args = data;
 
-	if (!args->conf || args->unified_fd < 0 || args->pid <= 0 ||
-	    args->sk_pair[0] < 0 || args->sk_pair[1] < 0)
+	if (!args->conf || !args->lxcpath || args->unified_fd < 0 ||
+	    args->pid <= 0 || args->sk_pair[0] < 0 || args->sk_pair[1] < 0)
 		return ret_errno(EINVAL);
 
 	close_prot_errno_disarm(args->sk_pair[0]);
 	return cgroup_attach_create_leaf(args->conf, args->unified_fd,
-					 &args->sk_pair[1]);
+					 &args->sk_pair[1], args->unprivileged);
 }
 
 static int cgroup_unified_attach_parent_wrapper(void *data)
@@ -1935,44 +2403,10 @@ static int cgroup_unified_attach_parent_wrapper(void *data)
 		return ret_errno(EINVAL);
 
 	close_prot_errno_disarm(args->sk_pair[1]);
-	return cgroup_attach_move_into_leaf(args->conf, &args->sk_pair[0],
-					    args->pid);
-}
-
-int cgroup_attach(const struct lxc_conf *conf, const char *name,
-		  const char *lxcpath, pid_t pid)
-{
-	__do_close int unified_fd = -EBADF;
-	int ret;
-
-	if (!conf || !name || !lxcpath || pid <= 0)
-		return ret_errno(EINVAL);
-
-	unified_fd = lxc_cmd_get_cgroup2_fd(name, lxcpath);
-	if (unified_fd < 0)
-		return ret_errno(EBADF);
-
-	if (!lxc_list_empty(&conf->id_map)) {
-		struct userns_exec_unified_attach_data args = {
-			.conf		= conf,
-			.unified_fd	= unified_fd,
-			.pid		= pid,
-		};
-
-		ret = socketpair(PF_LOCAL, SOCK_STREAM | SOCK_CLOEXEC, 0, args.sk_pair);
-		if (ret < 0)
-			return -errno;
-
-		ret = userns_exec_minimal(conf,
-					  cgroup_unified_attach_parent_wrapper,
-					  &args,
-					  cgroup_unified_attach_child_wrapper,
-					  &args);
-	} else {
-		ret = cgroup_attach_leaf(conf, unified_fd, pid);
-	}
-
-	return ret;
+	return cgroup_attach_move_into_leaf(args->conf, args->lxcpath,
+					    args->unified_fd,
+					    &args->sk_pair[0], args->pid,
+					    args->unprivileged);
 }
 
 /* Technically, we're always at a delegation boundary here (This is especially
@@ -1999,7 +2433,8 @@ static int __cg_unified_attach(const struct hierarchy *h,
 	ret = cgroup_attach(conf, name, lxcpath, pid);
 	if (ret == 0)
 		return log_trace(0, "Attached to unified cgroup via command handler");
-	if (ret != -EBADF)
+	TRACE("__cg_unified_attach: cgroup_attach returned %d", ret);
+	if (!ERRNO_IS_NOT_SUPPORTED(ret) && ret != -ENOCGROUP2)
 		return log_error_errno(ret, errno, "Failed to attach to unified cgroup");
 
 	/* Fall back to retrieving the path for the unified cgroup. */
@@ -2007,18 +2442,21 @@ static int __cg_unified_attach(const struct hierarchy *h,
 	/* not running */
 	if (!cgroup)
 		return 0;
+	TRACE("lxc_cmd_get_cgroup_path returned %s", cgroup);
 
-	path = must_make_path(h->at_mnt, cgroup, NULL);
+	path = make_cgroup_path(h, cgroup, NULL);
 
 	unified_fd = open(path, O_PATH | O_DIRECTORY | O_CLOEXEC);
 	if (unified_fd < 0)
 		return ret_errno(EBADF);
 
-	if (!lxc_list_empty(&conf->id_map)) {
+	if (!list_empty(&conf->id_map)) {
 		struct userns_exec_unified_attach_data args = {
 			.conf		= conf,
 			.unified_fd	= unified_fd,
 			.pid		= pid,
+			.unprivileged	= am_guest_unpriv(),
+			.lxcpath	= lxcpath,
 		};
 
 		ret = socketpair(PF_LOCAL, SOCK_STREAM | SOCK_CLOEXEC, 0, args.sk_pair);
@@ -2152,32 +2590,26 @@ static int device_cgroup_parse_access(struct device_item *device, const char *va
 	return 0;
 }
 
-int device_cgroup_rule_parse(struct device_item *device, const char *key,
+static int device_cgroup_rule_parse(struct device_item *device, const char *key,
 				    const char *val)
 {
-	int count, ret;
+	size_t count;
+	int ret;
 	char temp[50];
 
-	if (strcmp("devices.allow", key) == 0)
-		device->allow = 1;
+	if (strequal("devices.allow", key))
+		device->allow = 1; /* allow the device */
 	else
-		device->allow = 0;
+		device->allow = 0; /* deny the device */
 
-	if (strcmp(val, "a") == 0) {
+	if (strequal(val, "a")) {
 		/* global rule */
 		device->type = 'a';
 		device->major = -1;
 		device->minor = -1;
-		device->global_rule = device->allow
-					  ? LXC_BPF_DEVICE_CGROUP_BLACKLIST
-					  : LXC_BPF_DEVICE_CGROUP_WHITELIST;
-		device->allow = -1;
 		return 0;
 	}
 
-	/* local rule */
-	device->global_rule = LXC_BPF_DEVICE_CGROUP_LOCAL_RULE;
-
 	switch (*val) {
 	case 'a':
 		__fallthrough;
@@ -2300,7 +2732,9 @@ static int device_cgroup_rule_parse_devpath(struct device_item *device,
 	char *p;
 	struct stat sb;
 
-	path = must_copy_string(devpath);
+	path = strdup(devpath);
+	if (!path)
+		return ret_errno(ENOMEM);
 
 	/*
 	 * Read path followed by mode. Ignore any trailing text.
@@ -2329,9 +2763,6 @@ static int device_cgroup_rule_parse_devpath(struct device_item *device,
 	if (device_cgroup_parse_access(device, mode) < 0)
 		return -1;
 
-	if (n_parts == 1)
-		return ret_set_errno(-1, EINVAL);
-
 	ret = stat(path, &sb);
 	if (ret < 0)
 		return ret_set_errno(-1, errno);
@@ -2351,7 +2782,6 @@ static int device_cgroup_rule_parse_devpath(struct device_item *device,
 	device->major = MAJOR(sb.st_rdev);
 	device->minor = MINOR(sb.st_rdev);
 	device->allow = 1;
-	device->global_rule = LXC_BPF_DEVICE_CGROUP_LOCAL_RULE;
 
 	return 0;
 }
@@ -2481,15 +2911,38 @@ retry:
 	return ret;
 }
 
+/*
+ * Return the list of cgroup_settings sorted according to the following rules
+ * 1. Put memory.limit_in_bytes before memory.memsw.limit_in_bytes
+ */
+static void sort_cgroup_settings(struct lxc_conf *conf)
+{
+	LIST_HEAD(memsw_list);
+	struct lxc_cgroup *cgroup, *ncgroup;
+
+	/* Iterate over the cgroup settings and copy them to the output list. */
+	list_for_each_entry_safe(cgroup, ncgroup, &conf->cgroup, head) {
+		if (!strequal(cgroup->subsystem, "memory.memsw.limit_in_bytes"))
+			continue;
+
+		/* Move the memsw entry from the cgroup settings list. */
+		list_move_tail(&cgroup->head, &memsw_list);
+	}
+
+	/*
+	 * Append all the memsw entries to the end of the cgroup settings list
+	 * to make sure they are applied after all memory limit settings.
+	 */
+	list_splice_tail(&memsw_list, &conf->cgroup);
+
+}
+
 __cgfsng_ops static bool isulad_cgfsng_setup_limits_legacy(struct cgroup_ops *ops,
 						    struct lxc_conf *conf,
 						    bool do_devices)
 {
-	__do_free struct lxc_list *sorted_cgroup_settings = NULL;
-	struct lxc_list *cgroup_settings = &conf->cgroup;
-	struct lxc_list *iterator, *next;
-	struct lxc_cgroup *cg;
-	bool ret = false;
+	struct list_head *cgroup_settings;
+	struct lxc_cgroup *cgroup;
 	char value[21 + 1] = { 0 };
 	long long int readvalue, setvalue;
 
@@ -2500,7 +2953,7 @@ __cgfsng_ops static bool isulad_cgfsng_setup_limits_legacy(struct cgroup_ops *op
 		return ret_set_errno(false, EINVAL);
 
 	cgroup_settings = &conf->cgroup;
-	if (lxc_list_empty(cgroup_settings))
+	if (list_empty(cgroup_settings))
 		return true;
 
 	if (!ops->hierarchies)
@@ -2509,75 +2962,63 @@ __cgfsng_ops static bool isulad_cgfsng_setup_limits_legacy(struct cgroup_ops *op
 	if (pure_unified_layout(ops))
 		return true;
 
-	sorted_cgroup_settings = sort_cgroup_settings(cgroup_settings);
-	if (!sorted_cgroup_settings)
-		return false;
-
-	lxc_list_for_each(iterator, sorted_cgroup_settings) {
-		cg = iterator->elem;
-
-		if (do_devices == !strncmp("devices", cg->subsystem, 7)) {
-			const char *cgvalue = cg->value;
-			if (strcmp(cg->subsystem, "files.limit") == 0) {
+	sort_cgroup_settings(conf);
+	list_for_each_entry(cgroup, cgroup_settings, head) {
+		if (do_devices == strnequal("devices", cgroup->subsystem, 7)) {
+			const char *cgvalue = cgroup->value;
+			if (strcmp(cgroup->subsystem, "files.limit") == 0) {
 				if (lxc_safe_long_long(cgvalue, &setvalue) != 0) {
 					SYSERROR("Invalid integer value %s", cgvalue);
-					goto out;
+					return false;
 				}
 				if (setvalue <= 0) {
 					cgvalue = "max";
 				}
 			}
-			if (isulad_cg_legacy_set_data(ops, cg->subsystem, cgvalue)) {
+			if (isulad_cg_legacy_set_data(ops, cgroup->subsystem, cgvalue)) {
 				if (do_devices && (errno == EACCES || errno == EPERM)) {
-					SYSWARN("Failed to set \"%s\" to \"%s\"", cg->subsystem, cgvalue);
+					SYSWARN("Failed to set \"%s\" to \"%s\"", cgroup->subsystem, cgvalue);
 					continue;
 				}
-				SYSERROR("Failed to set \"%s\" to \"%s\"", cg->subsystem, cgvalue);
-				goto out;
+				SYSERROR("Failed to set \"%s\" to \"%s\"", cgroup->subsystem, cgvalue);
+				return false;
 			}
-			DEBUG("Set controller \"%s\" set to \"%s\"", cg->subsystem, cgvalue);
+			DEBUG("Set controller \"%s\" set to \"%s\"", cgroup->subsystem, cgvalue);
 		}
 
 		// isulad: check cpu shares
-		if (strcmp(cg->subsystem, "cpu.shares") == 0) {
-			if (isulad_cg_legacy_get_data(ops, cg->subsystem, value, sizeof(value) - 1) < 0) {
-				SYSERROR("Error get %s", cg->subsystem);
-				goto out;
+		if (strcmp(cgroup->subsystem, "cpu.shares") == 0) {
+			if (isulad_cg_legacy_get_data(ops, cgroup->subsystem, value, sizeof(value) - 1) < 0) {
+				SYSERROR("Error get %s", cgroup->subsystem);
+				return false;
 			}
 			trim(value);
-			if (lxc_safe_long_long(cg->value, &setvalue) != 0) {
-				SYSERROR("Invalid value %s", cg->value);
-				goto out;
+			if (lxc_safe_long_long(cgroup->value, &setvalue) != 0) {
+				SYSERROR("Invalid value %s", cgroup->value);
+				return false;
 			}
 			if (lxc_safe_long_long(value, &readvalue) != 0) {
 				SYSERROR("Invalid value %s", value);
-				goto out;
+				return false;
 			}
 			if (setvalue > readvalue) {
 				ERROR("The maximum allowed cpu-shares is %s", value);
 				lxc_write_error_message(ops->errfd,
 				                        "%s:%d: setting cgroup config for ready process caused \"The maximum allowed cpu-shares is %s\".",
 				                        __FILE__, __LINE__, value);
-				goto out;
+				return false;
 			} else if (setvalue < readvalue) {
 				ERROR("The minimum allowed cpu-shares is %s", value);
 				lxc_write_error_message(ops->errfd,
 				                        "%s:%d: setting cgroup config for ready process caused \"The minimum allowed cpu-shares is %s\".",
 				                        __FILE__, __LINE__, value);
-				goto out;
+				return false;
 			}
 		}
 	}
 
-	ret = true;
 	INFO("Limits for the legacy cgroup hierarchies have been setup");
-out:
-	lxc_list_for_each_safe(iterator, sorted_cgroup_settings, next) {
-		lxc_list_del(iterator);
-		free(iterator);
-	}
-
-	return ret;
+	return true;
 }
 
 /*
@@ -2588,31 +3029,35 @@ static int bpf_device_cgroup_prepare(struct cgroup_ops *ops,
 				     struct lxc_conf *conf, const char *key,
 				     const char *val)
 {
-#ifdef HAVE_STRUCT_BPF_CGROUP_DEV_CTX
-	struct device_item device_item = {0};
+	struct device_item device_item = {};
 	int ret;
 
-	if (strcmp("devices.allow", key) == 0 && *val == '/')
+	if (strequal("devices.allow", key) && abspath(val))
 		ret = device_cgroup_rule_parse_devpath(&device_item, val);
 	else
 		ret = device_cgroup_rule_parse(&device_item, key, val);
 	if (ret < 0)
-		return log_error_errno(-1, EINVAL, "Failed to parse device string %s=%s", key, val);
+		return syserror_set(EINVAL, "Failed to parse device rule %s=%s", key, val);
 
-	ret = bpf_list_add_device(conf, &device_item);
+	/*
+	 * Note that bpf_list_add_device() returns 1 if it altered the device
+	 * list and 0 if it didn't; both return values indicate success.
+	 * Only a negative return value indicates an error.
+	 */
+	ret = bpf_list_add_device(&conf->bpf_devices, &device_item);
 	if (ret < 0)
 		return -1;
-#endif
+
 	return 0;
 }
-
 __cgfsng_ops static bool isulad_cgfsng_setup_limits(struct cgroup_ops *ops,
 					     struct lxc_handler *handler)
 {
 	__do_free char *path = NULL;
-	struct lxc_list *cgroup_settings, *iterator;
+	struct list_head *cgroup_settings;
 	struct hierarchy *h;
 	struct lxc_conf *conf;
+	struct lxc_cgroup *cg;
 
 	if (!ops)
 		return ret_set_errno(false, ENOENT);
@@ -2627,7 +3072,7 @@ __cgfsng_ops static bool isulad_cgfsng_setup_limits(struct cgroup_ops *ops,
 		return ret_set_errno(false, EINVAL);
 	conf = handler->conf;
 
-	if (lxc_list_empty(&conf->cgroup2))
+	if (list_empty(&conf->cgroup2))
 		return true;
 	cgroup_settings = &conf->cgroup2;
 
@@ -2638,8 +3083,7 @@ __cgfsng_ops static bool isulad_cgfsng_setup_limits(struct cgroup_ops *ops,
 		return false;
 	h = ops->unified;
 
-	lxc_list_for_each (iterator, cgroup_settings) {
-		struct lxc_cgroup *cg = iterator->elem;
+	list_for_each_entry(cg, cgroup_settings, head) {
 		int ret;
 
 		if (strncmp("devices", cg->subsystem, 7) == 0) {
@@ -2786,7 +3230,7 @@ bool __cgfsng_delegate_controllers(struct cgroup_ops *ops, const char *cgroup)
 		(void)strlcat(add_controllers, "+", full_len + 1);
 		(void)strlcat(add_controllers, *it, full_len + 1);
 
-		if ((it + 1) && *(it + 1))
+		if (*(it + 1))
 			(void)strlcat(add_controllers, " ", full_len + 1);
 	}
 
@@ -2836,333 +3280,490 @@ __cgfsng_ops bool isulad_cgfsng_payload_delegate_controllers(struct cgroup_ops *
 	return __cgfsng_delegate_controllers(ops, ops->container_cgroup);
 }
 
-static bool cgroup_use_wants_controllers(const struct cgroup_ops *ops,
-				       char **controllers)
+static inline bool unified_cgroup(const char *line)
 {
-	if (!ops->cgroup_use)
-		return true;
+	return *line == '0';
+}
 
-	for (char **cur_ctrl = controllers; cur_ctrl && *cur_ctrl; cur_ctrl++) {
-		bool found = false;
+static inline char *current_unified_cgroup(bool relative, char *line)
+{
+	char *current_cgroup;
 
-		for (char **cur_use = ops->cgroup_use; cur_use && *cur_use; cur_use++) {
-			if (strcmp(*cur_use, *cur_ctrl) != 0)
-				continue;
+	line += STRLITERALLEN("0::");
 
-			found = true;
-			break;
-		}
+	if (!abspath(line))
+		return ERR_PTR(-EINVAL);
 
-		if (found)
-			continue;
+	/* remove init.scope */
+	if (!relative)
+		line = prune_init_scope(line);
 
-		return false;
-	}
+	/* create a relative path */
+	line = deabs(line);
 
-	return true;
+	current_cgroup = strdup(line);
+	if (!current_cgroup)
+		return ERR_PTR(-ENOMEM);
+
+	return current_cgroup;
 }
 
-static void cg_unified_delegate(char ***delegate)
+static inline const char *unprefix(const char *controllers)
 {
+	if (strnequal(controllers, "name=", STRLITERALLEN("name=")))
+		return controllers + STRLITERALLEN("name=");
+	return controllers;
+}
+
+static int __list_cgroup_delegate(char ***delegate)
+{
+	__do_free char **list = NULL;
 	__do_free char *buf = NULL;
-	char *standard[] = {"cgroup.subtree_control", "cgroup.threads", NULL};
+	char *standard[] = {
+		"cgroup.procs",
+		"cgroup.threads",
+		"cgroup.subtree_control",
+		"memory.oom.group",
+		NULL,
+	};
 	char *token;
-	int idx;
+	int ret;
 
-	buf = read_file("/sys/kernel/cgroup/delegate");
+	buf = read_file_at(-EBADF, "/sys/kernel/cgroup/delegate", PROTECT_OPEN, 0);
 	if (!buf) {
 		for (char **p = standard; p && *p; p++) {
-			idx = append_null_to_list((void ***)delegate);
-			(*delegate)[idx] = must_copy_string(*p);
+			ret = list_add_string(&list, *p);
+			if (ret < 0)
+				return ret;
 		}
-		SYSWARN("Failed to read /sys/kernel/cgroup/delegate");
-		return;
+
+		*delegate = move_ptr(list);
+		return syswarn_ret(0, "Failed to read /sys/kernel/cgroup/delegate");
 	}
 
-	lxc_iterate_parts (token, buf, " \t\n") {
+	lxc_iterate_parts(token, buf, " \t\n") {
 		/*
 		 * We always need to chown this for both cgroup and
 		 * cgroup2.
 		 */
-		if (strcmp(token, "cgroup.procs") == 0)
+		if (strequal(token, "cgroup.procs"))
 			continue;
 
-		idx = append_null_to_list((void ***)delegate);
-		(*delegate)[idx] = must_copy_string(token);
+		ret = list_add_string(&list, token);
+		if (ret < 0)
+			return ret;
 	}
+
+	*delegate = move_ptr(list);
+	return 0;
 }
 
-/* At startup, parse_hierarchies finds all the info we need about cgroup
- * mountpoints and current cgroups, and stores it in @d.
- */
-static int cg_hybrid_init(struct cgroup_ops *ops, bool relative, bool unprivileged)
+static bool unified_hierarchy_delegated(int dfd_base, char ***ret_files)
 {
-	__do_free char *basecginfo = NULL, *line = NULL;
-	__do_free_string_list char **klist = NULL, **nlist = NULL;
-	__do_fclose FILE *f = NULL;
+	__do_free_string_list char **list = NULL;
 	int ret;
-	size_t len = 0;
 
-	/* Root spawned containers escape the current cgroup, so use init's
-	 * cgroups as our base in that case.
-	 */
-	if (!relative && (geteuid() == 0))
-		basecginfo = read_file("/proc/1/cgroup");
-	else
-		basecginfo = read_file("/proc/self/cgroup");
-	if (!basecginfo)
-		return ret_set_errno(-1, ENOMEM);
-
-	ret = get_existing_subsystems(&klist, &nlist);
+	ret = __list_cgroup_delegate(&list);
 	if (ret < 0)
-		return log_error_errno(-1, errno, "Failed to retrieve available legacy cgroup controllers");
+		return syserror_ret(ret, "Failed to determine unified cgroup delegation requirements");
 
-	f = fopen("/proc/self/mountinfo", "re");
-	if (!f)
-		return log_error_errno(-1, errno, "Failed to open \"/proc/self/mountinfo\"");
+	for (char *const *s = list; s && *s; s++) {
+		if (!faccessat(dfd_base, *s, W_OK, 0) || errno == ENOENT)
+			continue;
 
-	lxc_cgfsng_print_basecg_debuginfo(basecginfo, klist, nlist);
+		return sysinfo_ret(false, "The %s file is not writable, skipping unified hierarchy", *s);
+	}
 
-	while (getline(&line, &len, f) != -1) {
-		__do_free char *base_cgroup = NULL, *mountpoint = NULL;
-		__do_free_string_list char **controller_list = NULL;
-		int type;
-		struct hierarchy *new;
+	*ret_files = move_ptr(list);
+	return true;
+}
 
-		type = get_cgroup_version(line);
-		if (type == 0)
-			continue;
+static bool legacy_hierarchy_delegated(int dfd_base)
+{
+	int ret;
 
-		if (type == CGROUP2_SUPER_MAGIC && ops->unified)
-			continue;
+	ret = faccessat(dfd_base, ".", W_OK, 0);
+	if (ret < 0 && errno != ENOENT)
+		return sysinfo_ret(false, "Legacy hierarchy not writable, skipping");
 
-		if (ops->cgroup_layout == CGROUP_LAYOUT_UNKNOWN) {
-			if (type == CGROUP2_SUPER_MAGIC)
-				ops->cgroup_layout = CGROUP_LAYOUT_UNIFIED;
-			else if (type == CGROUP_SUPER_MAGIC)
-				ops->cgroup_layout = CGROUP_LAYOUT_LEGACY;
-		} else if (ops->cgroup_layout == CGROUP_LAYOUT_UNIFIED) {
-			if (type == CGROUP_SUPER_MAGIC)
-				ops->cgroup_layout = CGROUP_LAYOUT_HYBRID;
-		} else if (ops->cgroup_layout == CGROUP_LAYOUT_LEGACY) {
-			if (type == CGROUP2_SUPER_MAGIC)
-				ops->cgroup_layout = CGROUP_LAYOUT_HYBRID;
-		}
+	return true;
+}
 
-		controller_list = cg_hybrid_get_controllers(klist, nlist, line, type);
-		if (!controller_list && type == CGROUP_SUPER_MAGIC)
-			continue;
+/**
+ * systemd guarantees that the order of co-mounted controllers is stable. On
+ * some systems the order of the controllers might be reversed though.
+ *
+ * For example, this is how the order is mismatched on CentOS 7:
+ *
+ *      [root@localhost ~]# cat /proc/self/cgroup
+ *      11:perf_event:/
+ *      10:pids:/
+ *      9:freezer:/
+ * >>>> 8:cpuacct,cpu:/
+ *      7:memory:/
+ *      6:blkio:/
+ *      5:devices:/
+ *      4:hugetlb:/
+ * >>>> 3:net_prio,net_cls:/
+ *      2:cpuset:/
+ *      1:name=systemd:/user.slice/user-0.slice/session-c1.scope
+ *
+ * whereas the mountpoint:
+ *
+ *      | |-/sys/fs/cgroup                    tmpfs         tmpfs      ro,nosuid,nodev,noexec,mode=755
+ *      | | |-/sys/fs/cgroup/systemd          cgroup        cgroup     rw,nosuid,nodev,noexec,relatime,xattr,release_agent=/usr/lib/systemd/systemd-cgroups-agent,name=systemd
+ *      | | |-/sys/fs/cgroup/cpuset           cgroup        cgroup     rw,nosuid,nodev,noexec,relatime,cpuset
+ * >>>> | | |-/sys/fs/cgroup/net_cls,net_prio cgroup        cgroup     rw,nosuid,nodev,noexec,relatime,net_prio,net_cls
+ *      | | |-/sys/fs/cgroup/hugetlb          cgroup        cgroup     rw,nosuid,nodev,noexec,relatime,hugetlb
+ *      | | |-/sys/fs/cgroup/devices          cgroup        cgroup     rw,nosuid,nodev,noexec,relatime,devices
+ *      | | |-/sys/fs/cgroup/blkio            cgroup        cgroup     rw,nosuid,nodev,noexec,relatime,blkio
+ *      | | |-/sys/fs/cgroup/memory           cgroup        cgroup     rw,nosuid,nodev,noexec,relatime,memory
+ * >>>> | | |-/sys/fs/cgroup/cpu,cpuacct      cgroup        cgroup     rw,nosuid,nodev,noexec,relatime,cpuacct,cpu
+ *      | | |-/sys/fs/cgroup/freezer          cgroup        cgroup     rw,nosuid,nodev,noexec,relatime,freezer
+ *      | | |-/sys/fs/cgroup/pids             cgroup        cgroup     rw,nosuid,nodev,noexec,relatime,pids
+ *      | | `-/sys/fs/cgroup/perf_event       cgroup        cgroup     rw,nosuid,nodev,noexec,relatime,perf_event
+ *
+ * Ensure that we always use the systemd-guaranteed stable order when checking
+ * for the mountpoint.
+ */
+#if HAVE_COMPILER_ATTR_NONNULL
+__attribute__((nonnull))
+#endif
+#if HAVE_COMPILER_ATTR_RETURNS_NONNULL
+__attribute__((returns_nonnull))
+#endif
+static const char *stable_order(const char *controllers)
+{
+	if (strequal(controllers, "cpuacct,cpu"))
+		return "cpu,cpuacct";
 
-		if (type == CGROUP_SUPER_MAGIC)
-			if (controller_list_is_dup(ops->hierarchies, controller_list)) {
-				TRACE("Skipping duplicating controller");
-				continue;
-			}
+	if (strequal(controllers, "net_prio,net_cls"))
+		return "net_cls,net_prio";
 
-		mountpoint = cg_hybrid_get_mountpoint(line);
-		if (!mountpoint) {
-			WARN("Failed parsing mountpoint from \"%s\"", line);
-			continue;
-		}
+	return unprefix(controllers);
+}
 
-		if (type == CGROUP_SUPER_MAGIC)
-			base_cgroup = cg_hybrid_get_current_cgroup(basecginfo, controller_list[0], CGROUP_SUPER_MAGIC);
-		else
-			base_cgroup = cg_hybrid_get_current_cgroup(basecginfo, NULL, CGROUP2_SUPER_MAGIC);
-		if (!base_cgroup) {
-			WARN("Failed to find current cgroup");
-			continue;
-		}
+#define CGFSNG_LAYOUT_LEGACY	BIT(0)
+#define CGFSNG_LAYOUT_UNIFIED	BIT(1)
 
-		trim(base_cgroup);
-		prune_init_scope(base_cgroup);
+static int __initialize_cgroups(struct cgroup_ops *ops, bool relative,
+				bool unprivileged, struct lxc_conf *conf)
+{
+	__do_free char *cgroup_info = NULL;
+	unsigned int layout_mask = 0;
+	int ret;
+	char *it;
 
-		/* isulad: do not test writeable, if we run isulad in docker without cgroup namespace.
-		 * the base_cgroup will be docker/XXX.., mountpoint+base_cgroup may be not exist */
+	ret = unpriv_systemd_create_scope(ops, conf);
+	if (ret < 0)
+		return ret_set_errno(false, ret);
+	else if (ret == 0)
+		TRACE("Entered an unpriv systemd scope");
 
-		/*
-		 * reason:base cgroup may be started with /system.slice when cg_hybrid_init
-		 *	read /proc/1/cgroup on host, and cgroup init will set all containers
-		 *	cgroup path under /sys/fs/cgroup/<controller>/system.slice/xxx/lxc
-		 *	directory, this is not consistent with docker. The default cgroup path
-		 *	should be under /sys/fs/cgroup/<controller>/lxc directory.
-		 */
+	/*
+	 * Root spawned containers escape the current cgroup, so use init's
+	 * cgroups as our base in that case.
+	 */
+	if (!relative && (geteuid() == 0))
+		cgroup_info = read_file_at(-EBADF, "/proc/1/cgroup", PROTECT_OPEN, 0);
+	else
+		cgroup_info = read_file_at(-EBADF, "/proc/self/cgroup", PROTECT_OPEN, 0);
+	if (!cgroup_info)
+		return ret_errno(ENOMEM);
+
+	lxc_iterate_parts(it, cgroup_info, "\n") {
+		__do_close int dfd_base = -EBADF, dfd_mnt = -EBADF;
+		__do_free char *controllers = NULL, *current_cgroup = NULL;
+		__do_free_string_list char **controller_list = NULL,
+					   **delegate = NULL;
+		char *line;
+		int dfd, type;
+
+		/* Handle the unified cgroup hierarchy. */
+		line = it;
+		if (unified_cgroup(line)) {
+			char *unified_mnt;
+
+			type = UNIFIED_HIERARCHY;
+			layout_mask |= CGFSNG_LAYOUT_UNIFIED;
+
+			if (conf->cgroup_meta.systemd_scope)
+				current_cgroup = cgroup_relpath(conf->cgroup_meta.systemd_scope);
+			if (IS_ERR_OR_NULL(current_cgroup))
+				current_cgroup = current_unified_cgroup(relative, line);
+			if (IS_ERR(current_cgroup))
+				return PTR_ERR(current_cgroup);
+
+			if (unified_cgroup_fd(ops->dfd_mnt)) {
+				dfd_mnt = dup_cloexec(ops->dfd_mnt);
+				unified_mnt = "";
+			} else {
+				dfd_mnt = open_at(ops->dfd_mnt,
+						  "unified",
+						  PROTECT_OPATH_DIRECTORY,
+						  PROTECT_LOOKUP_ABSOLUTE_XDEV, 0);
+				unified_mnt = "unified";
+			}
+			if (dfd_mnt < 0) {
+				if (errno != ENOENT)
+					return syserror("Failed to open %d/unified", ops->dfd_mnt);
 
-		if (strlen(base_cgroup) > 1 && base_cgroup[0] == '/') {
-			base_cgroup[1] = '\0';
-		}
+				SYSTRACE("Unified cgroup not mounted");
+				continue;
+			}
+
+			if (!fhas_fs_type(dfd_mnt, CGROUP2_SUPER_MAGIC)) {
+				SYSTRACE("Opened file descriptor %d is not a cgroup2 mountpoint", dfd_mnt);
+				continue;
+			}
 
-		if (type == CGROUP2_SUPER_MAGIC) {
-			char *cgv2_ctrl_path;
+			dfd = dfd_mnt;
+
+			if (!is_empty_string(current_cgroup)) {
+				dfd_base = open_at(dfd_mnt, current_cgroup,
+						   PROTECT_OPATH_DIRECTORY,
+						   PROTECT_LOOKUP_BENEATH_XDEV, 0);
+				if (dfd_base < 0) {
+					if (errno != ENOENT)
+						return syserror("Failed to open %d/%s",
+								dfd_mnt, current_cgroup);
+
+					SYSTRACE("Current cgroup %d/%s does not exist (funky cgroup layout?)",
+						 dfd_mnt, current_cgroup);
+					continue;
+				}
+				dfd = dfd_base;
+			}
 
-			cgv2_ctrl_path = must_make_path(mountpoint, base_cgroup,
-							"cgroup.controllers",
-							NULL);
+			if (!unified_hierarchy_delegated(dfd, &delegate))
+				continue;
 
-			controller_list = cg_unified_get_controllers(cgv2_ctrl_path);
-			free(cgv2_ctrl_path);
+			controller_list = unified_controllers(dfd, "cgroup.controllers");
 			if (!controller_list) {
-				controller_list = cg_unified_make_empty_controller();
-				TRACE("No controllers are enabled for "
-				      "delegation in the unified hierarchy");
+				TRACE("No controllers are enabled for delegation in the unified hierarchy");
+				controller_list = list_new();
+				if (!controller_list)
+					return syserror_set(-ENOMEM, "Failed to create empty controller list");
 			}
-		}
 
-		/* Exclude all controllers that cgroup use does not want. */
-		if (!cgroup_use_wants_controllers(ops, controller_list)) {
-			TRACE("Skipping controller");
-			continue;
-		}
+			controllers = strdup(unified_mnt);
+			if (!controllers)
+				return ret_errno(ENOMEM);
+		} else {
+			char *__controllers, *__current_cgroup;
+
+			type = LEGACY_HIERARCHY;
+			layout_mask |= CGFSNG_LAYOUT_LEGACY;
+
+			__controllers = strchr(line, ':');
+			if (!__controllers)
+				return ret_errno(EINVAL);
+			__controllers++;
+
+			__current_cgroup = strchr(__controllers, ':');
+			if (!__current_cgroup)
+				return ret_errno(EINVAL);
+			*__current_cgroup = '\0';
+			__current_cgroup++;
+
+			controllers = strdup(stable_order(__controllers));
+			if (!controllers)
+				return ret_errno(ENOMEM);
+
+			dfd_mnt = open_at(ops->dfd_mnt,
+					  controllers,
+					  PROTECT_OPATH_DIRECTORY,
+					  PROTECT_LOOKUP_ABSOLUTE_XDEV, 0);
+			if (dfd_mnt < 0) {
+				if (errno != ENOENT)
+					return syserror("Failed to open %d/%s",
+							ops->dfd_mnt, controllers);
+
+				SYSTRACE("%s not mounted", controllers);
+				continue;
+			}
 
-		new = add_hierarchy(&ops->hierarchies, move_ptr(controller_list), move_ptr(mountpoint), move_ptr(base_cgroup), type);
-		if (type == CGROUP2_SUPER_MAGIC && !ops->unified) {
-			if (unprivileged)
-				cg_unified_delegate(&new->cgroup2_chown);
-			ops->unified = new;
-		}
-	}
+			if (!fhas_fs_type(dfd_mnt, CGROUP_SUPER_MAGIC)) {
+				SYSTRACE("Opened file descriptor %d is not a cgroup mountpoint", dfd_mnt);
+				continue;
+			}
 
-	TRACE("Writable cgroup hierarchies:");
-	lxc_cgfsng_print_hierarchies(ops);
+			dfd = dfd_mnt;
 
-	/* verify that all controllers in cgroup.use and all crucial
-	 * controllers are accounted for
-	 */
-	if (!all_controllers_found(ops))
-		return log_error_errno(-1, ENOENT, "Failed to find all required controllers");
+			if (!abspath(__current_cgroup))
+				return ret_errno(EINVAL);
 
-	return 0;
-}
+			/* remove init.scope */
+			if (!relative)
+				__current_cgroup = prune_init_scope(__current_cgroup);
 
-/* Get current cgroup from /proc/self/cgroup for the cgroupfs v2 hierarchy. */
-static char *cg_unified_get_current_cgroup(bool relative)
-{
-	__do_free char *basecginfo = NULL;
-	char *copy;
-	char *base_cgroup;
+			/* create a relative path */
+			__current_cgroup = deabs(__current_cgroup);
 
-	if (!relative && (geteuid() == 0))
-		basecginfo = read_file("/proc/1/cgroup");
-	else
-		basecginfo = read_file("/proc/self/cgroup");
-	if (!basecginfo)
-		return NULL;
+			current_cgroup = strdup(__current_cgroup);
+			if (!current_cgroup)
+				return ret_errno(ENOMEM);
 
-	base_cgroup = strstr(basecginfo, "0::/");
-	if (!base_cgroup)
-		return NULL;
+			if (!is_empty_string(current_cgroup)) {
+				dfd_base = open_at(dfd_mnt, current_cgroup,
+						   PROTECT_OPATH_DIRECTORY,
+						   PROTECT_LOOKUP_BENEATH_XDEV, 0);
+				if (dfd_base < 0) {
+					if (errno != ENOENT)
+						return syserror("Failed to open %d/%s",
+								dfd_mnt, current_cgroup);
 
-	base_cgroup = base_cgroup + 3;
-	copy = copy_to_eol(base_cgroup);
-	if (!copy)
-		return NULL;
+					SYSTRACE("Current cgroup %d/%s does not exist (funky cgroup layout?)",
+						 dfd_mnt, current_cgroup);
+					continue;
+				}
+				dfd = dfd_base;
+			}
 
-	return trim(copy);
-}
+			if (!legacy_hierarchy_delegated(dfd))
+				continue;
 
-static int cg_unified_init(struct cgroup_ops *ops, bool relative,
-			   bool unprivileged)
-{
-	__do_free char *subtree_path = NULL;
-	int ret;
-	char *mountpoint;
-	char **delegatable;
-	struct hierarchy *new;
-	char *base_cgroup = NULL;
+			/*
+			 * We intentionally pass __current_cgroup here and not
+			 * controllers because we would otherwise chop the
+			 * mountpoint.
+			 */
+			controller_list = list_add_controllers(__controllers);
+			if (!controller_list)
+				return syserror_set(-ENOMEM, "Failed to create controller list from %s", __controllers);
 
-	ret = unified_cgroup_hierarchy();
-	if (ret == -ENOMEDIUM)
-		return ret_errno(ENOMEDIUM);
+			if (skip_hierarchy(ops, controller_list))
+				continue;
 
-	if (ret != CGROUP2_SUPER_MAGIC)
-		return 0;
+			ops->cgroup_layout = CGROUP_LAYOUT_LEGACY;
+		}
 
-	base_cgroup = cg_unified_get_current_cgroup(relative);
-	if (!base_cgroup)
-		return ret_errno(EINVAL);
-	if (!relative)
-		prune_init_scope(base_cgroup);
+		ret = cgroup_hierarchy_add(ops, dfd_mnt, controllers, dfd,
+					   current_cgroup, controller_list, type);
+		if (ret < 0)
+			return syserror_ret(ret, "Failed to add %s hierarchy", controllers);
+
+		/* Transfer ownership. */
+		move_fd(dfd_mnt);
+		move_fd(dfd_base);
+		move_ptr(current_cgroup);
+		move_ptr(controllers);
+		move_ptr(controller_list);
+		if (type == UNIFIED_HIERARCHY)
+			ops->unified->delegate = move_ptr(delegate);
+	}
 
-	/*
-	 * We assume that the cgroup we're currently in has been delegated to
-	 * us and we are free to further delege all of the controllers listed
-	 * in cgroup.controllers further down the hierarchy.
-	 */
-	mountpoint = must_copy_string(DEFAULT_CGROUP_MOUNTPOINT);
-	subtree_path = must_make_path(mountpoint, base_cgroup, "cgroup.controllers", NULL);
-	delegatable = cg_unified_get_controllers(subtree_path);
-	if (!delegatable)
-		delegatable = cg_unified_make_empty_controller();
-	if (!delegatable[0]) {
-		TRACE("No controllers are enabled for delegation");
-#ifdef HAVE_ISULAD
-		ops->no_controller = true;
-#endif
+	/* determine cgroup layout */
+	if (ops->unified) {
+		if (ops->cgroup_layout == CGROUP_LAYOUT_LEGACY) {
+			ops->cgroup_layout = CGROUP_LAYOUT_HYBRID;
+		} else {
+			if (bpf_devices_cgroup_supported())
+				ops->unified->utilities |= DEVICES_CONTROLLER;
+			ops->cgroup_layout = CGROUP_LAYOUT_UNIFIED;
+		}
 	}
 
-	/* TODO: If the user requested specific controllers via lxc.cgroup.use
-	 * we should verify here. The reason I'm not doing it right is that I'm
-	 * not convinced that lxc.cgroup.use will be the future since it is a
-	 * global property. I much rather have an option that lets you request
-	 * controllers per container.
+	/*
+	 * If we still don't know the cgroup layout at this point it means we
+	 * have not found any writable cgroup hierarchies. Infer the layout
+	 * from the layout bitmask we created when parsing the cgroups.
+	 *
+	 * Keep the ordering in the switch otherwise the bistmask-based
+	 * matching won't work.
 	 */
+	if (ops->cgroup_layout == CGROUP_LAYOUT_UNKNOWN) {
+		switch (layout_mask) {
+		case (CGFSNG_LAYOUT_LEGACY | CGFSNG_LAYOUT_UNIFIED):
+			ops->cgroup_layout = CGROUP_LAYOUT_HYBRID;
+			break;
+		case CGFSNG_LAYOUT_LEGACY:
+			ops->cgroup_layout = CGROUP_LAYOUT_LEGACY;
+			break;
+		case CGFSNG_LAYOUT_UNIFIED:
+			ops->cgroup_layout = CGROUP_LAYOUT_UNIFIED;
+			break;
+		}
+	}
 
-	new = add_hierarchy(&ops->hierarchies, delegatable, mountpoint, base_cgroup, CGROUP2_SUPER_MAGIC);
-	if (unprivileged)
-		cg_unified_delegate(&new->cgroup2_chown);
-
-	if (bpf_devices_cgroup_supported())
-		new->bpf_device_controller = 1;
-
-	ops->cgroup_layout = CGROUP_LAYOUT_UNIFIED;
-	ops->unified = new;
+	if (!controllers_available(ops))
+		return syserror_set(-ENOENT, "One or more requested controllers unavailable or not delegated");
 
-	return CGROUP2_SUPER_MAGIC;
+	return 0;
 }
 
-static int isulad_cg_init(struct cgroup_ops *ops, struct lxc_conf *conf)
+static int isulad_initialize_cgroups(struct cgroup_ops *ops, struct lxc_conf *conf)
 {
+	__do_close int dfd = -EBADF;
 	int ret;
-	const char *tmp;
-	bool relative = conf->cgroup_meta.relative;
+	const char *controllers_use;
 
-	tmp = lxc_global_config_value("lxc.cgroup.use");
-	if (tmp) {
-		__do_free char *pin = NULL;
-		char *chop, *cur;
+	if (ops->dfd_mnt >= 0)
+		return ret_errno(EBUSY);
+
+	/*
+	 * I don't see the need for allowing symlinks here. If users want to
+	 * have their hierarchy available in different locations I strongly
+	 * suggest bind-mounts.
+	 */
+	dfd = open_at(-EBADF, DEFAULT_CGROUP_MOUNTPOINT,
+			PROTECT_OPATH_DIRECTORY, PROTECT_LOOKUP_ABSOLUTE_XDEV, 0);
+	if (dfd < 0)
+		return syserror("Failed to open " DEFAULT_CGROUP_MOUNTPOINT);
+
+	controllers_use = lxc_global_config_value("lxc.cgroup.use");
+	if (controllers_use) {
+		__do_free char *dup = NULL;
+		char *it;
 
-		pin = must_copy_string(tmp);
-		chop = pin;
+		dup = strdup(controllers_use);
+		if (!dup)
+			return -errno;
 
-		lxc_iterate_parts(cur, chop, ",")
-			must_append_string(&ops->cgroup_use, cur);
+		lxc_iterate_parts(it, dup, ",") {
+			ret = list_add_string(&ops->cgroup_use, it);
+			if (ret < 0)
+				return ret;
+		}
 	}
 
-	ret = cg_unified_init(ops, relative, !lxc_list_empty(&conf->id_map));
-	if (ret < 0)
-		return -1;
+	/*
+	 * Keep dfd referenced by the cleanup function and actually move the fd
+	 * once we know the initialization succeeded. So if we fail we clean up
+	 * the dfd.
+	 */
+	ops->dfd_mnt = dfd;
 
-	if (ret == CGROUP2_SUPER_MAGIC)
-		return 0;
+	ret = __initialize_cgroups(ops, conf->cgroup_meta.relative, !list_empty(&conf->id_map), conf);
+	if (ret < 0)
+		return syserror_ret(ret, "Failed to initialize cgroups");
 
-	return cg_hybrid_init(ops, relative, !lxc_list_empty(&conf->id_map));
+	/* Transfer ownership to cgroup_ops. */
+	move_fd(dfd);
+	return 0;
 }
 
 __cgfsng_ops static int isulad_cgfsng_data_init(struct cgroup_ops *ops, struct lxc_conf *conf)
 {
 	const char *cgroup_pattern;
+#ifdef HAVE_ISULAD
 	const char *cgroup_tree;
 	__do_free char *container_cgroup = NULL, *__cgroup_tree = NULL;
 	size_t len;
+#endif
 
 	if (!ops)
 		return ret_set_errno(-1, ENOENT);
 
 	/* copy system-wide cgroup information */
 	cgroup_pattern = lxc_global_config_value("lxc.cgroup.pattern");
-	if (cgroup_pattern && strcmp(cgroup_pattern, "") != 0)
-		ops->cgroup_pattern = must_copy_string(cgroup_pattern);
+	if (cgroup_pattern && !strequal(cgroup_pattern, "")) {
+		ops->cgroup_pattern = strdup(cgroup_pattern);
+		if (!ops->cgroup_pattern)
+			return ret_errno(ENOMEM);
+	}
 
+#ifdef HAVE_ISULAD
 	if (conf->cgroup_meta.dir) {
 		cgroup_tree = conf->cgroup_meta.dir;
 		container_cgroup = must_concat(&len, cgroup_tree, "/", conf->name, NULL);
@@ -3181,22 +3782,23 @@ __cgfsng_ops static int isulad_cgfsng_data_init(struct cgroup_ops *ops, struct l
 		return ret_set_errno(-1, ENOMEM);
 
 	ops->container_cgroup = move_ptr(container_cgroup);
+#endif
 
 	return 0;
 }
 
-struct cgroup_ops *cgfsng_ops_init(struct lxc_conf *conf)
+struct cgroup_ops *cgroup_ops_init(struct lxc_conf *conf)
 {
-	__do_free struct cgroup_ops *cgfsng_ops = NULL;
+	__cleanup_cgroup_ops struct cgroup_ops *cgfsng_ops = NULL;
 
-	cgfsng_ops = malloc(sizeof(struct cgroup_ops));
+	cgfsng_ops = zalloc(sizeof(struct cgroup_ops));
 	if (!cgfsng_ops)
 		return ret_set_errno(NULL, ENOMEM);
 
-	memset(cgfsng_ops, 0, sizeof(struct cgroup_ops));
-	cgfsng_ops->cgroup_layout = CGROUP_LAYOUT_UNKNOWN;
+	cgfsng_ops->cgroup_layout	= CGROUP_LAYOUT_UNKNOWN;
+	cgfsng_ops->dfd_mnt		= -EBADF;
 
-	if (isulad_cg_init(cgfsng_ops, conf))
+	if (isulad_initialize_cgroups(cgfsng_ops, conf))
 		return NULL;
 
 	cgfsng_ops->data_init = isulad_cgfsng_data_init;
@@ -3211,10 +3813,7 @@ struct cgroup_ops *cgfsng_ops_init(struct lxc_conf *conf)
 	cgfsng_ops->payload_delegate_controllers = isulad_cgfsng_payload_delegate_controllers;
 	cgfsng_ops->payload_create = isulad_cgfsng_payload_create;
 	cgfsng_ops->payload_enter = isulad_cgfsng_payload_enter;
-	cgfsng_ops->payload_finalize = isulad_cgfsng_payload_finalize;
-	cgfsng_ops->escape = isulad_cgfsng_escape;
-	cgfsng_ops->num_hierarchies = isulad_cgfsng_num_hierarchies;
-	cgfsng_ops->get_hierarchies = isulad_cgfsng_get_hierarchies;
+	cgfsng_ops->finalize = isulad_cgfsng_finalize;
 	cgfsng_ops->get_cgroup = isulad_cgfsng_get_cgroup;
 	cgfsng_ops->get = isulad_cgfsng_get;
 	cgfsng_ops->set = isulad_cgfsng_set;
@@ -3229,5 +3828,310 @@ struct cgroup_ops *cgfsng_ops_init(struct lxc_conf *conf)
 	cgfsng_ops->mount = isulad_cgfsng_mount;
 	cgfsng_ops->devices_activate = isulad_cgfsng_devices_activate;
 
+	cgfsng_ops->criu_escape = isulad_cgfsng_criu_escape;
+	cgfsng_ops->criu_num_hierarchies = isulad_cgfsng_criu_num_hierarchies;
+	cgfsng_ops->criu_get_hierarchies = isulad_cgfsng_criu_get_hierarchies;
+
 	return move_ptr(cgfsng_ops);
 }
+
+static int __unified_attach_fd(const struct lxc_conf *conf, const char *lxcpath, int fd_unified, pid_t pid)
+{
+	int ret;
+
+	if (!list_empty(&conf->id_map)) {
+		struct userns_exec_unified_attach_data args = {
+			.conf		= conf,
+			.unified_fd	= fd_unified,
+			.pid		= pid,
+			.unprivileged	= am_guest_unpriv(),
+			.lxcpath	= lxcpath,
+		};
+
+		ret = socketpair(PF_LOCAL, SOCK_STREAM | SOCK_CLOEXEC, 0, args.sk_pair);
+		if (ret < 0)
+			return -errno;
+
+		ret = userns_exec_minimal(conf,
+					  cgroup_unified_attach_parent_wrapper,
+					  &args,
+					  cgroup_unified_attach_child_wrapper,
+					  &args);
+	} else {
+		ret = cgroup_attach_leaf(conf, fd_unified, pid);
+	}
+
+	return ret;
+}
+
+static int __cgroup_attach_many(const struct lxc_conf *conf, const char *name,
+				const char *lxcpath, pid_t pid)
+{
+	call_cleaner(put_cgroup_ctx) struct cgroup_ctx *ctx = &(struct cgroup_ctx){};
+	int ret;
+	size_t idx;
+	ssize_t pidstr_len;
+	char pidstr[INTTYPE_TO_STRLEN(pid_t)];
+
+	ret = lxc_cmd_get_cgroup_ctx(name, lxcpath, sizeof(struct cgroup_ctx), ctx);
+	if (ret < 0)
+		return ret_errno(ENOSYS);
+
+	if (ctx->fd_len == 0)
+		return log_trace(0, "Container runs with unwritable %s cgroup layout",
+				 cgroup_layout_name(ctx->layout));
+
+	pidstr_len = strnprintf(pidstr, sizeof(pidstr), "%d", pid);
+	if (pidstr_len < 0)
+		return pidstr_len;
+
+	for (idx = 0; idx < ctx->fd_len; idx++) {
+		int dfd_con = ctx->fd[idx];
+
+		if (unified_cgroup_fd(dfd_con))
+			ret = __unified_attach_fd(conf, lxcpath, dfd_con, pid);
+		else
+			ret = lxc_writeat(dfd_con, "cgroup.procs", pidstr, pidstr_len);
+		if (ret)
+			return syserror_ret(ret, "Failed to attach to cgroup fd %d", dfd_con);
+		else
+			TRACE("Attached to cgroup fd %d", dfd_con);
+	}
+
+	TRACE("Attached to %s cgroup layout", cgroup_layout_name(ctx->layout));
+	return 0;
+}
+
+static int __cgroup_attach_unified(const struct lxc_conf *conf, const char *name,
+				   const char *lxcpath, pid_t pid)
+{
+	__do_close int dfd_unified = -EBADF;
+
+	if (!conf || is_empty_string(name) || is_empty_string(lxcpath) || pid <= 0)
+		return ret_errno(EINVAL);
+
+	dfd_unified = lxc_cmd_get_cgroup2_fd(name, lxcpath);
+	if (dfd_unified < 0)
+		return ret_errno(ENOSYS);
+
+	return __unified_attach_fd(conf, lxcpath, dfd_unified, pid);
+}
+
+int cgroup_attach(const struct lxc_conf *conf, const char *name,
+		  const char *lxcpath, pid_t pid)
+{
+	int ret;
+
+	ret = __cgroup_attach_many(conf, name, lxcpath, pid);
+	if (ret < 0) {
+		if (!ERRNO_IS_NOT_SUPPORTED(ret))
+			return ret;
+
+		ret = __cgroup_attach_unified(conf, name, lxcpath, pid);
+		if (ret < 0 && ERRNO_IS_NOT_SUPPORTED(ret))
+			return ret_errno(ENOSYS);
+	}
+
+	return ret;
+}
+
+/* Connects to command socket therefore isn't callable from command handler. */
+int cgroup_get(const char *name, const char *lxcpath, const char *key, char *buf, size_t len)
+{
+	__do_close int dfd = -EBADF;
+	struct cgroup_fd fd = {
+		.fd = -EBADF,
+	};
+	size_t len_controller;
+	int ret;
+
+	if (is_empty_string(name) || is_empty_string(lxcpath) ||
+	    is_empty_string(key))
+		return ret_errno(EINVAL);
+
+	if ((buf && !len) || (len && !buf))
+		return ret_errno(EINVAL);
+
+	len_controller = strcspn(key, ".");
+	len_controller++; /* Don't forget the \0 byte. */
+	if (len_controller >= MAX_CGROUP_ROOT_NAMELEN)
+		return ret_errno(EINVAL);
+	(void)strlcpy(fd.controller, key, len_controller);
+
+	ret = lxc_cmd_get_limit_cgroup_fd(name, lxcpath, sizeof(struct cgroup_fd), &fd);
+	if (ret < 0) {
+		if (!ERRNO_IS_NOT_SUPPORTED(ret))
+			return ret;
+
+		dfd = lxc_cmd_get_limit_cgroup2_fd(name, lxcpath);
+		if (dfd < 0) {
+			if (!ERRNO_IS_NOT_SUPPORTED(ret))
+				return ret;
+
+			return ret_errno(ENOSYS);
+		}
+		fd.type = UNIFIED_HIERARCHY;
+		fd.fd = move_fd(dfd);
+	}
+	dfd = move_fd(fd.fd);
+
+	TRACE("Reading %s from %s cgroup hierarchy", key, cgroup_hierarchy_name(fd.type));
+
+	if (fd.type == UNIFIED_HIERARCHY && strequal(fd.controller, "devices"))
+		return ret_errno(EOPNOTSUPP);
+	else
+		ret = lxc_read_try_buf_at(dfd, key, buf, len);
+
+	return ret;
+}
+
+/* Connects to command socket therefore isn't callable from command handler. */
+int cgroup_set(const char *name, const char *lxcpath, const char *key, const char *value)
+{
+	__do_close int dfd = -EBADF;
+	struct cgroup_fd fd = {
+		.fd = -EBADF,
+	};
+	size_t len_controller;
+	int ret;
+
+	if (is_empty_string(name) || is_empty_string(lxcpath) ||
+	    is_empty_string(key) || is_empty_string(value))
+		return ret_errno(EINVAL);
+
+	len_controller = strcspn(key, ".");
+	len_controller++; /* Don't forget the \0 byte. */
+	if (len_controller >= MAX_CGROUP_ROOT_NAMELEN)
+		return ret_errno(EINVAL);
+	(void)strlcpy(fd.controller, key, len_controller);
+
+	ret = lxc_cmd_get_limit_cgroup_fd(name, lxcpath, sizeof(struct cgroup_fd), &fd);
+	if (ret < 0) {
+		if (!ERRNO_IS_NOT_SUPPORTED(ret))
+			return ret;
+
+		dfd = lxc_cmd_get_limit_cgroup2_fd(name, lxcpath);
+		if (dfd < 0) {
+			if (!ERRNO_IS_NOT_SUPPORTED(ret))
+				return ret;
+
+			return ret_errno(ENOSYS);
+		}
+		fd.type = UNIFIED_HIERARCHY;
+		fd.fd = move_fd(dfd);
+	}
+	dfd = move_fd(fd.fd);
+
+	TRACE("Setting %s to %s in %s cgroup hierarchy", key, value, cgroup_hierarchy_name(fd.type));
+
+	if (fd.type == UNIFIED_HIERARCHY && strequal(fd.controller, "devices")) {
+		struct device_item device = {};
+
+		ret = device_cgroup_rule_parse(&device, key, value);
+		if (ret < 0)
+			return log_error_errno(-1, EINVAL, "Failed to parse device string %s=%s",
+					       key, value);
+
+		ret = lxc_cmd_add_bpf_device_cgroup(name, lxcpath, &device);
+	} else {
+		ret = lxc_writeat(dfd, key, value, strlen(value));
+	}
+
+	return ret;
+}
+
+static int do_cgroup_freeze(int unified_fd,
+			    const char *state_string,
+			    int state_num,
+			    int timeout,
+			    const char *epoll_error,
+			    const char *wait_error)
+{
+	__do_close int events_fd = -EBADF;
+	call_cleaner(lxc_mainloop_close) struct lxc_async_descr *descr_ptr = NULL;
+	int ret;
+	struct lxc_async_descr descr = {};
+
+	if (timeout != 0) {
+		ret = lxc_mainloop_open(&descr);
+		if (ret)
+			return log_error_errno(-1, errno, "%s", epoll_error);
+
+		/* automatically cleaned up now */
+		descr_ptr = &descr;
+
+		events_fd = open_at(unified_fd, "cgroup.events", PROTECT_OPEN, PROTECT_LOOKUP_BENEATH, 0);
+		if (events_fd < 0)
+			return log_error_errno(-errno, errno, "Failed to open cgroup.events file");
+
+		ret = lxc_mainloop_add_handler_events(&descr, events_fd, EPOLLPRI,
+						      freezer_cgroup_events_cb,
+						      default_cleanup_handler,
+						      INT_TO_PTR(state_num),
+						      "freezer_cgroup_events_cb");
+		if (ret < 0)
+			return log_error_errno(-1, errno, "Failed to add cgroup.events fd handler to mainloop");
+	}
+
+	ret = lxc_writeat(unified_fd, "cgroup.freeze", state_string, 1);
+	if (ret < 0)
+		return log_error_errno(-1, errno, "Failed to open cgroup.freeze file");
+
+	if (timeout != 0) {
+		ret = lxc_mainloop(&descr, timeout);
+		if (ret)
+			return log_error_errno(-1, errno, "%s", wait_error);
+	}
+
+	return log_trace(0, "Container now %s", (state_num == 1) ? "frozen" : "unfrozen");
+}
+
+static inline int __cgroup_freeze(int unified_fd, int timeout)
+{
+	return do_cgroup_freeze(unified_fd, "1", 1, timeout,
+			        "Failed to create epoll instance to wait for container freeze",
+			        "Failed to wait for container to be frozen");
+}
+
+int cgroup_freeze(const char *name, const char *lxcpath, int timeout)
+{
+	__do_close int unified_fd = -EBADF;
+	int ret;
+
+	if (is_empty_string(name) || is_empty_string(lxcpath))
+		return ret_errno(EINVAL);
+
+	unified_fd = lxc_cmd_get_limit_cgroup2_fd(name, lxcpath);
+	if (unified_fd < 0)
+		return ret_errno(ENOCGROUP2);
+
+	lxc_cmd_notify_state_listeners(name, lxcpath, FREEZING);
+	ret = __cgroup_freeze(unified_fd, timeout);
+	lxc_cmd_notify_state_listeners(name, lxcpath, !ret ? FROZEN : RUNNING);
+	return ret;
+}
+
+int __cgroup_unfreeze(int unified_fd, int timeout)
+{
+	return do_cgroup_freeze(unified_fd, "0", 0, timeout,
+			        "Failed to create epoll instance to wait for container freeze",
+			        "Failed to wait for container to be frozen");
+}
+
+int cgroup_unfreeze(const char *name, const char *lxcpath, int timeout)
+{
+	__do_close int unified_fd = -EBADF;
+	int ret;
+
+	if (is_empty_string(name) || is_empty_string(lxcpath))
+		return ret_errno(EINVAL);
+
+	unified_fd = lxc_cmd_get_limit_cgroup2_fd(name, lxcpath);
+	if (unified_fd < 0)
+		return ret_errno(ENOCGROUP2);
+
+	lxc_cmd_notify_state_listeners(name, lxcpath, THAWED);
+	ret = __cgroup_unfreeze(unified_fd, timeout);
+	lxc_cmd_notify_state_listeners(name, lxcpath, !ret ? RUNNING : FROZEN);
+	return ret;
+}
diff --git a/src/lxc/commands.c b/src/lxc/commands.c
index 2188b31..bf63cac 100644
--- a/src/lxc/commands.c
+++ b/src/lxc/commands.c
@@ -1991,7 +1991,7 @@ int lxc_cmd_set_terminal_fifos(const char *name, const char *lxcpath, const char
 }
 
 static int lxc_cmd_set_terminal_fifos_callback(int fd, struct lxc_cmd_req *req,
-					struct lxc_handler *handler, struct lxc_epoll_descr *descr)
+					struct lxc_handler *handler, struct lxc_async_descr *descr)
 {
 	struct lxc_cmd_rsp rsp;
 	memset(&rsp, 0, sizeof(rsp));
@@ -2037,7 +2037,7 @@ int lxc_cmd_set_terminal_winch(const char *name, const char *lxcpath, unsigned i
 }
 
 static int lxc_cmd_set_terminal_winch_callback(int fd, struct lxc_cmd_req *req,
-					struct lxc_handler *handler, struct lxc_epoll_descr *descr)
+					struct lxc_handler *handler, struct lxc_async_descr *descr)
 {
 	struct lxc_cmd_rsp rsp;
 	struct lxc_cmd_set_terminal_winch_request *data = (struct lxc_cmd_set_terminal_winch_request *)(req->data);
diff --git a/src/lxc/conf.c b/src/lxc/conf.c
index 187e60e..34cf90a 100644
--- a/src/lxc/conf.c
+++ b/src/lxc/conf.c
@@ -299,15 +299,15 @@ static struct limit_opt limit_opt[] = {
 static int rootfs_parent_mount_private(char *rootfs);
 static int setup_rootfs_ropaths(struct lxc_list *ropaths);
 static int setup_rootfs_maskedpaths(struct lxc_list *maskedpaths);
-static int remount_proc_sys_mount_entries(struct lxc_list *mount_list, bool lsm_aa_allow_nesting);
+static int remount_proc_sys_mount_entries(struct list_head *mount_entries, bool lsm_aa_allow_nesting);
 static int check_mount_destination(const char *rootfs, const char *dest, const char *src);
 static int mount_entry_with_loop_dev(const char *src, const char *dest, const char *fstype,
 		char *mnt_opts, const char *rootfs);
-static bool need_setup_proc(const struct lxc_conf *conf, struct lxc_list *mount);
-static bool need_setup_dev(const struct lxc_conf *conf, struct lxc_list *mount);
+static bool need_setup_proc(const struct lxc_conf *conf, struct list_head *mount);
+static bool need_setup_dev(const struct lxc_conf *conf, struct list_head *mount);
 static int setup_populate_devs(const struct lxc_rootfs *rootfs, struct lxc_list *devs, const char *mount_label);
 static int setup_rootfs_mountopts(const struct lxc_rootfs *rootfs);
-static int create_mtab_link();
+static int create_mtab_link(void);
 #endif
 
 static int run_buffer(char *buffer)
@@ -1252,8 +1252,13 @@ static int lxc_send_ttys_to_parent(struct lxc_handler *handler)
 /* Just create a path for /dev under $lxcpath/$name and in rootfs If we hit an
  * error, log it but don't fail yet.
  */
+#ifdef HAVE_ISULAD
+static int mount_autodev(const char *name, const struct lxc_rootfs *rootfs,
+			 int autodevtmpfssize, const char *lxcpath, char *systemd, const char *mount_label)
+#else
 static int mount_autodev(const char *name, const struct lxc_rootfs *rootfs,
 			 int autodevtmpfssize, const char *lxcpath)
+#endif
 {
 #ifndef HAVE_ISULAD
 	__do_close int fd_fs = -EBADF;
@@ -1905,18 +1910,21 @@ static int lxc_setup_devpts_child(struct lxc_handler *handler)
 		 */
 #ifdef HAVE_ISULAD
 		if (rootfs->lsm_se_mount_context != NULL) {
-			ret = strnprintf(devpts_mntopts, sizeof(devpts_mntopts), "%s,max=%zu,context=\"%s\"",
-					default_devpts_mntopts, pty_max, rootfs->lsm_se_mount_context);
+			if (asprintf(&devpts_mntopts, "%s,max=%zu,context=\"%s\"",
+				default_devpts_mntopts, conf->pty_max, conf->rootfs.lsm_se_mount_context) < 0) {
+				return -1;
+			}
 		} else {
+			if (asprintf(&devpts_mntopts, "%s,max=%zu", default_devpts_mntopts, conf->pty_max) < 0) {
+				return -1;
+			}
+		}
 #else
 		ret = strnprintf(devpts_mntopts, sizeof(devpts_mntopts), "%s,max=%zu",
 				default_devpts_mntopts, pty_max);
-#endif
-#ifdef HAVE_ISULAD
-		}
-#endif
 		if (ret < 0)
 			return -1;
+#endif
 
 		/* Create mountpoint for devpts instance. */
 		ret = mkdirat(rootfs->dfd_dev, "pts", 0755);
@@ -2079,7 +2087,7 @@ static int bind_mount_console(int fd_devpts, struct lxc_rootfs *rootfs,
 	__do_free char *mnt_opts = NULL;
 
 	if (rootfs->lsm_se_mount_context != NULL) {
-		if (asprintf(mnt_opts, "context=\"%s\"", rootfs->lsm_se_mount_context) < 0) {
+		if (asprintf(&mnt_opts, "context=\"%s\"", rootfs->lsm_se_mount_context) < 0) {
 			return syserror("Out of memory");
 		}
 	}
@@ -2181,7 +2189,7 @@ static int lxc_setup_ttydir_console(int fd_devpts, struct lxc_rootfs *rootfs,
 	__do_free char *mnt_opts = NULL;
 
 	if (rootfs->lsm_se_mount_context != NULL) {
-		if (asprintf(mnt_opts, "context=\"%s\"", rootfs->lsm_se_mount_context) < 0) {
+		if (asprintf(&mnt_opts, "context=\"%s\"", rootfs->lsm_se_mount_context) < 0) {
 			return syserror("Out of memory");
 		}
 	}
@@ -2968,8 +2976,13 @@ static int mount_entry_on_relative_rootfs(struct mntent *mntent,
 	return mount_entry_on_generic(mntent, rootfs->buf, rootfs, lxc_name, lxc_path);
 }
 
+#ifdef HAVE_ISULAD
+static int mount_file_entries(const struct lxc_conf *conf, struct lxc_rootfs *rootfs, FILE *file,
+			      const char *lxc_name, const char *lxc_path)
+#else
 static int mount_file_entries(struct lxc_rootfs *rootfs, FILE *file,
 			      const char *lxc_name, const char *lxc_path)
+#endif
 {
 	char buf[PATH_MAX];
 	struct mntent mntent;
@@ -3030,8 +3043,13 @@ static inline void __auto_endmntent__(FILE **f)
 
 #define __do_endmntent __attribute__((__cleanup__(__auto_endmntent__)))
 
+#ifdef HAVE_ISULAD
+static int setup_mount_fstab(const struct lxc_conf *conf, struct lxc_rootfs *rootfs, const char *fstab,
+			     const char *lxc_name, const char *lxc_path)
+#else
 static int setup_mount_fstab(struct lxc_rootfs *rootfs, const char *fstab,
 			     const char *lxc_name, const char *lxc_path)
+#endif
 {
 	__do_endmntent FILE *f = NULL;
 	int ret;
@@ -3043,7 +3061,11 @@ static int setup_mount_fstab(struct lxc_rootfs *rootfs, const char *fstab,
 	if (!f)
 		return log_error_errno(-1, errno, "Failed to open \"%s\"", fstab);
 
+#ifdef HAVE_ISULAD
+	ret = mount_file_entries(conf, rootfs, f, lxc_name, lxc_path);
+#else
 	ret = mount_file_entries(rootfs, f, lxc_name, lxc_path);
+#endif
 	if (ret < 0)
 		ERROR("Failed to set up mount entries");
 
@@ -3126,8 +3148,11 @@ static int setup_mount_entries(const struct lxc_conf *conf,
 	f = make_anonymous_mount_file(&conf->mount_entries, conf->lsm_aa_allow_nesting);
 	if (!f)
 		return -1;
-
+#ifdef HAVE_ISULAD
+	return mount_file_entries(conf, rootfs, f, lxc_name, lxc_path);
+#else
 	return mount_file_entries(rootfs, f, lxc_name, lxc_path);
+#endif
 }
 
 static int __lxc_idmapped_mounts_child(struct lxc_handler *handler, FILE *f)
@@ -3540,7 +3565,11 @@ static int parse_resource(const char *res)
 	return resid;
 }
 
+#ifdef HAVE_ISULAD
+int setup_resource_limits(struct lxc_conf *conf, pid_t pid, int errfd)
+#else
 int setup_resource_limits(struct lxc_conf *conf, pid_t pid)
+#endif
 {
 	int resid;
 	struct lxc_limit *lim;
@@ -3554,8 +3583,17 @@ int setup_resource_limits(struct lxc_conf *conf, pid_t pid)
 			return log_error(-1, "Unknown resource %s", lim->resource);
 
 #if HAVE_PRLIMIT || HAVE_PRLIMIT64
+#ifdef HAVE_ISULAD
+		if (prlimit(pid, resid, &lim->limit, NULL) != 0) {
+			lxc_write_error_message(errfd, "%s:%d: Failed to set limit %s %lu %lu: %s.",
+					__FILE__, __LINE__, lim->resource,
+					lim->limit.rlim_cur, lim->limit.rlim_max, strerror(errno));
+			return log_error_errno(-1, errno, "Failed to set limit %s", lim->resource);
+		}
+#else
 		if (prlimit(pid, resid, &lim->limit, NULL) != 0)
 			return log_error_errno(-1, errno, "Failed to set limit %s", lim->resource);
+#endif
 
 		TRACE("Setup \"%s\" limit", lim->resource);
 #else
@@ -4099,8 +4137,11 @@ domount:
 			ret = strnprintf(rootfs->buf, sizeof(rootfs->buf), "%s/proc", rootfs->path ? rootfs->mount : "");
 			if (ret < 0)
 				return ret_errno(EIO);
-
+#ifdef HAVE_ISULAD
+			ret = safe_mount("proc", rootfs->buf, "proc", 0, NULL, rootfs->mount, NULL);
+#else
 			ret = safe_mount("proc", rootfs->buf, "proc", 0, NULL, rootfs->mount);
+#endif
 		}
 	}
 	if (ret < 0)
@@ -4675,7 +4716,12 @@ int lxc_setup(struct lxc_handler *handler)
 	}
 
 	if (lxc_conf->autodev > 0) {
+#ifdef HAVE_ISULAD
+		ret = mount_autodev(name, &lxc_conf->rootfs, lxc_conf->autodevtmpfssize, lxcpath,
+							lxc_conf->systemd, lxc_conf->rootfs.lsm_se_mount_context);
+#else
 		ret = mount_autodev(name, &lxc_conf->rootfs, lxc_conf->autodevtmpfssize, lxcpath);
+#endif
 		if (ret < 0)
 			return log_error(-1, "Failed to mount \"/dev\"");
 	}
@@ -4697,7 +4743,11 @@ int lxc_setup(struct lxc_handler *handler)
 		return log_error(-1, "Failed to setup remaining automatic mounts");
 #endif
 
+#ifdef HAVE_ISULAD
+	ret = setup_mount_fstab(lxc_conf, &lxc_conf->rootfs, lxc_conf->fstab, name, lxcpath);
+#else
 	ret = setup_mount_fstab(&lxc_conf->rootfs, lxc_conf->fstab, name, lxcpath);
+#endif
 	if (ret < 0)
 		return log_error(-1, "Failed to setup mounts");
 
@@ -4750,6 +4800,15 @@ int lxc_setup(struct lxc_handler *handler)
 			return log_error(-1, "Failed to populate \"/dev\"");
 	}
 
+#ifdef HAVE_ISULAD
+	/* isulad: setup devices which will be populated in the container. */
+	if (!lxc_list_empty(&lxc_conf->populate_devs) && setup_dev) {
+		if (setup_populate_devs(&lxc_conf->rootfs, &lxc_conf->populate_devs, lxc_conf->rootfs.lsm_se_mount_context) != 0) {
+			return log_error(-1, "Failed to setup devices in the container");
+		}
+	}
+#endif
+
 	/* Make sure any start hooks are in the container */
 	if (!verify_start_hooks(lxc_conf))
 		return log_error(-1, "Failed to verify start hooks");
@@ -4796,7 +4855,7 @@ int lxc_setup(struct lxc_handler *handler)
 
 #ifdef HAVE_ISULAD
 	/* Ask father to run oci prestart hooks and wait for him to finish. */
-	if (lxc_sync_wait_parent(handler, LXC_SYNC_OCI_PRESTART_HOOK)) {
+	if (lxc_sync_barrier_parent(handler, START_SYNC_OCI_PRESTART_HOOK)) {
 		return log_error(-1, "Failed to sync parent to start host hook");
 	}
 #endif
@@ -4845,10 +4904,10 @@ int lxc_setup(struct lxc_handler *handler)
 		}
 	}
 
-	//isulad: system container, remount /proc/sys/xxx by mount_list
+	//isulad: system container, remount /proc/sys/xxx by mount_entries
 	if (lxc_conf->systemd != NULL && strcmp(lxc_conf->systemd, "true") == 0) {
-		if (!lxc_list_empty(&lxc_conf->mount_list)) {
-			if (remount_proc_sys_mount_entries(&lxc_conf->mount_list,
+		if (!list_empty(&lxc_conf->mount_entries)) {
+			if (remount_proc_sys_mount_entries(&lxc_conf->mount_entries,
 							   lxc_conf->lsm_aa_allow_nesting)) {
 				return log_error(-1, "failed to remount /proc/sys");
 			}
@@ -5250,7 +5309,7 @@ void lxc_conf_free(struct lxc_conf *conf)
 	if (conf->ocihooks) {
 		free_oci_runtime_spec_hooks(conf->ocihooks);
 	}
-	free(conf->lsm_se_mount_context);
+	free(conf->rootfs.lsm_se_mount_context);
 	free(conf->lsm_se_keyring_context);
 #endif
 
@@ -6184,19 +6243,22 @@ int lxc_drop_caps(struct lxc_conf *conf)
 #define __DEF_CAP_TO_MASK(x) (1U << ((x) & 31))
 #if HAVE_LIBCAP
 	int ret = 0;
-	struct lxc_list *iterator = NULL;
-	char *keep_entry = NULL;
+	int nret = 0;
 	size_t i = 0;
-	int capid;
-	size_t numcaps = (size_t)lxc_caps_last_cap() + 1;
-	struct lxc_list *caps = NULL;
+	__u32 capid;
+	__u32 last_cap;
+	size_t numcaps;
+	struct cap_entry *cap_entry;
 	int *caplist = NULL;
 
-	if (lxc_list_empty(&conf->keepcaps))
+	if (!conf->caps.keep)
 		return 0;
 
-	caps = &conf->keepcaps;
+	ret = lxc_caps_last_cap(&last_cap);
+	if (ret)
+		return -1;
 
+	numcaps = (size_t)last_cap + 1;
 	if (numcaps <= 0 || numcaps > 200)
 		return -1;
 
@@ -6208,11 +6270,9 @@ int lxc_drop_caps(struct lxc_conf *conf)
 	}
 	(void)memset(caplist, 0, numcaps * sizeof(int));
 
-	lxc_list_for_each(iterator, caps) {
-
-		keep_entry = iterator->elem;
+	list_for_each_entry(cap_entry, &conf->caps.list, head) {
 		/* isulad: Do not keep any cap*/
-		if (strcmp(keep_entry, "ISULAD_KEEP_NONE") == 0) {
+		if (strcmp(cap_entry->cap_name, "ISULAD_KEEP_NONE") == 0) {
 			DEBUG("Do not keep any capability");
 			for(i = 0; i < numcaps; i++) {
 				caplist[i] = 0;
@@ -6220,18 +6280,17 @@ int lxc_drop_caps(struct lxc_conf *conf)
 			break;
 		}
 
-		capid = parse_cap(keep_entry);
-
-		if (capid == -2)
+		nret = parse_cap(cap_entry->cap_name, &capid);
+		if (nret == -2)
 			continue;
 
-		if (capid < 0) {
-			ERROR("unknown capability %s", keep_entry);
+		if (nret < 0) {
+			ERROR("unknown capability %s", cap_entry->cap_name);
 			ret = -1;
 			goto out;
 		}
 
-		DEBUG("keep capability '%s' (%d)", keep_entry, capid);
+		DEBUG("keep capability '%s' (%d)", cap_entry->cap_name, capid);
 
 		caplist[capid] = 1;
 	}
@@ -6299,7 +6358,7 @@ static bool have_dev_bind_mount_entry(FILE *file)
 }
 
 // returns true if /dev needs to be set up.
-static bool need_setup_dev(const struct lxc_conf *conf, struct lxc_list *mount)
+static bool need_setup_dev(const struct lxc_conf *conf, struct list_head *mount)
 {
 	__do_fclose FILE *f = NULL;
 
@@ -6344,7 +6403,7 @@ static bool have_proc_bind_mount_entry(FILE *file)
 }
 
 // returns true if /proc needs to be set up.
-static bool need_setup_proc(const struct lxc_conf *conf, struct lxc_list *mount)
+static bool need_setup_proc(const struct lxc_conf *conf, struct list_head *mount)
 {
 	__do_fclose FILE *f = NULL;
 
@@ -6378,7 +6437,7 @@ static int mount_entry_with_loop_dev(const char *src, const char *dest, const ch
 		if (srcfd < 0)
 			return srcfd;
 		ret = snprintf(srcbuf, sizeof(srcbuf), "/proc/self/fd/%d", srcfd);
-		if (ret < 0 || ret > sizeof(srcbuf)) {
+		if (ret < 0 || (size_t)ret > sizeof(srcbuf)) {
 			close(srcfd);
 			ERROR("Failed to print string");
 			return -EINVAL;
@@ -6397,7 +6456,7 @@ static int mount_entry_with_loop_dev(const char *src, const char *dest, const ch
 	}
 
 	ret = snprintf(destbuf, sizeof(destbuf), "/proc/self/fd/%d", destfd);
-	if (ret < 0 || ret > sizeof(destbuf)) {
+	if (ret < 0 || (size_t)ret > sizeof(destbuf)) {
 		if (srcfd != -1)
 			close(srcfd);
 		close(destfd);
@@ -6584,13 +6643,13 @@ on_error:
 	return false;
 }
 
-static int remount_proc_sys_mount_entries(struct lxc_list *mount_list, bool lsm_aa_allow_nesting)
+static int remount_proc_sys_mount_entries(struct list_head *mount_entries, bool lsm_aa_allow_nesting)
 {
 	char buf[4096];
 	FILE *file;
 	struct mntent mntent;
 
-	file = make_anonymous_mount_file(mount_list, lsm_aa_allow_nesting);
+	file = make_anonymous_mount_file(mount_entries, lsm_aa_allow_nesting);
 	if (!file)
 		return -1;
 
@@ -6824,21 +6883,57 @@ reset_umask:
 	return ret;
 }
 
+static void parse_propagationopt(char *opt, unsigned long *flags)
+{
+	struct mount_opt *mo;
+
+	/* If opt is found in propagation_opt, set or clear flags. */
+	for (mo = &propagation_opt[0]; mo->name != NULL; mo++) {
+		if (strncmp(opt, mo->name, strlen(mo->name)) != 0)
+			continue;
+
+		if (mo->clear)
+			*flags &= ~mo->flag;
+		else
+			*flags |= mo->flag;
+
+		return;
+	}
+}
+
+int parse_propagationopts(const char *mntopts, unsigned long *pflags)
+{
+	__do_free char *s = NULL;
+	char *p;
+
+	if (!mntopts)
+		return 0;
+
+	s = strdup(mntopts);
+	if (!s)
+		return log_error_errno(-ENOMEM, errno, "Failed to allocate memory");
+
+	*pflags = 0L;
+	lxc_iterate_parts(p, s, ",")
+		parse_propagationopt(p, pflags);
+
+	return 0;
+}
+
 // isulad: setup rootfs mountopts
 static int setup_rootfs_mountopts(const struct lxc_rootfs *rootfs)
 {
 	unsigned long mflags, mntflags, pflags;
 	__do_free char *mntdata = NULL;
 
-	if(!rootfs || !rootfs->options)
+	if(!rootfs || !rootfs->mnt_opts.raw_options)
 		return 0;
 
-	if (parse_mntopts_legacy(rootfs->options, &mntflags, &mntdata) < 0) {
+	if (parse_mntopts_legacy(rootfs->mnt_opts.raw_options, &mntflags, &mntdata) < 0) {
 		return -1;
 	}
 
-	ret = parse_propagationopts(rootfs->options, &pflags);
-	if (ret < 0) {
+	if (parse_propagationopts(rootfs->mnt_opts.raw_options, &pflags) < 0) {
 		return -EINVAL;
 	}
 
@@ -6853,7 +6948,7 @@ static int setup_rootfs_mountopts(const struct lxc_rootfs *rootfs)
 	return 0;
 }
 
-static int create_mtab_link()
+static int create_mtab_link(void)
 {
 	ssize_t ret;
 	int mret;
@@ -6935,7 +7030,7 @@ static char* generate_json_str(const char *name, const char *lxcpath, const char
 	rc = snprintf(inmsg, size,
 	              "{\"ociVersion\":\"\",\"id\":\"%s\",\"pid\":%s,\"root\":\"%s\",\"bundle\":\"%s/%s\"}",
 	              name, cpid, rootfs, lxcpath, name);
-	if (rc < 0 || rc >= size) {
+	if (rc < 0 || (size_t)rc >= size) {
 		ERROR("Create json string failed");
 		ret = -1;
 	}
@@ -7090,8 +7185,8 @@ static struct lxc_popen_FILE *lxc_popen_ocihook(const char *commandpath, char **
 	close(pipe_msg[0]);
 	pipe_msg[0]= -1;
 	if (instr) {
-		size_t len = strlen(instr);
-		if (lxc_write_nointr(pipe_msg[1], instr, len) != len) {
+		int len = lxc_write_nointr(pipe_msg[1], instr, strlen(instr));
+		if (len < 0 || (size_t)len != strlen(instr)) {
 			WARN("Write instr: %s failed", instr);
 		}
 	}
@@ -7413,7 +7508,7 @@ int run_oci_hooks(const char *name, const char *hookname, struct lxc_conf *conf,
 /*isulad clear init args*/
 int lxc_clear_init_args(struct lxc_conf *lxc_conf)
 {
-	int i;
+	size_t i;
 
 	for (i = 0; i < lxc_conf->init_argc; i++) {
 		free(lxc_conf->init_argv[i]);
diff --git a/src/lxc/conf.h b/src/lxc/conf.h
index 108e05b..ef4bb05 100644
--- a/src/lxc/conf.h
+++ b/src/lxc/conf.h
@@ -677,7 +677,11 @@ __hidden extern int lxc_setup_rootfs_prepare_root(struct lxc_conf *conf, const c
 						  const char *lxcpath);
 __hidden extern int lxc_setup(struct lxc_handler *handler);
 __hidden extern int lxc_setup_parent(struct lxc_handler *handler);
+#ifdef HAVE_ISULAD
+__hidden extern int setup_resource_limits(struct lxc_conf *conf, pid_t pid, int errfd);
+#else
 __hidden extern int setup_resource_limits(struct lxc_conf *conf, pid_t pid);
+#endif
 __hidden extern int find_unmapped_nsid(const struct lxc_conf *conf, enum idtype idtype);
 __hidden extern int mapped_hostid(unsigned id, const struct lxc_conf *conf, enum idtype idtype);
 __hidden extern int userns_exec_1(const struct lxc_conf *conf, int (*fn)(void *), void *data,
diff --git a/src/lxc/confile.c b/src/lxc/confile.c
index 1492776..0d0d66c 100644
--- a/src/lxc/confile.c
+++ b/src/lxc/confile.c
@@ -287,16 +287,16 @@ static struct lxc_config_t config_jump_table[] = {
 	{ "lxc.sysctl",                     false, set_config_sysctl,                     get_config_sysctl,                     clr_config_sysctl,                     },
 	{ "lxc.proc",                       false, set_config_proc,                       get_config_proc,                       clr_config_proc,                       },
 #ifdef HAVE_ISULAD
-	{ "lxc.isulad.init.args",          set_config_init_args,                   get_config_init_args,                   clr_config_init_args,                 },
-	{ "lxc.isulad.populate.device",    set_config_populate_device,             get_config_populate_device,             clr_config_populate_device,           },
-	{ "lxc.isulad.umask",              set_config_umask,                       get_config_umask,                       clr_config_umask,                     },
-	{ "lxc.isulad.rootfs.maskedpaths", set_config_rootfs_masked_paths,         get_config_rootfs_masked_paths,         clr_config_rootfs_masked_paths,       },
-	{ "lxc.isulad.rootfs.ropaths",     set_config_rootfs_ro_paths,             get_config_rootfs_ro_paths,             clr_config_rootfs_ro_paths,           },
-	{ "lxc.isulad.systemd",            set_config_systemd,                     get_config_systemd,                     clr_config_systemd,                   },
-	{ "lxc.console.logdriver",         set_config_console_log_driver,          get_config_console_log_driver,          clr_config_console_log_driver,        },
-	{ "lxc.console.syslog_tag",        set_config_console_syslog_tag,          get_config_console_syslog_tag,          clr_config_console_syslog_tag,        },
-	{ "lxc.console.syslog_facility",   set_config_console_syslog_facility,     get_config_console_syslog_facility,     clr_config_console_syslog_facility,   },
-	{ "lxc.selinux.mount_context",     set_config_selinux_mount_context,       get_config_selinux_mount_context,       clr_config_selinux_mount_context,     },
+	{ "lxc.isulad.init.args",          	true,	set_config_init_args,                   get_config_init_args,                   clr_config_init_args,                 },
+	{ "lxc.isulad.populate.device",    	true,	set_config_populate_device,             get_config_populate_device,             clr_config_populate_device,           },
+	{ "lxc.isulad.umask",              	true,	set_config_umask,                       get_config_umask,                       clr_config_umask,                     },
+	{ "lxc.isulad.rootfs.maskedpaths", 	true,	set_config_rootfs_masked_paths,         get_config_rootfs_masked_paths,         clr_config_rootfs_masked_paths,       },
+	{ "lxc.isulad.rootfs.ropaths",     	true,	set_config_rootfs_ro_paths,             get_config_rootfs_ro_paths,             clr_config_rootfs_ro_paths,           },
+	{ "lxc.isulad.systemd",            	true,	set_config_systemd,                     get_config_systemd,                     clr_config_systemd,                   },
+	{ "lxc.console.logdriver",         	true,	set_config_console_log_driver,          get_config_console_log_driver,          clr_config_console_log_driver,        },
+	{ "lxc.console.syslog_tag",        	true,	set_config_console_syslog_tag,          get_config_console_syslog_tag,          clr_config_console_syslog_tag,        },
+	{ "lxc.console.syslog_facility",   	true,	set_config_console_syslog_facility,     get_config_console_syslog_facility,     clr_config_console_syslog_facility,   },
+	{ "lxc.selinux.mount_context",     	true,	set_config_selinux_mount_context,       get_config_selinux_mount_context,       clr_config_selinux_mount_context,     },
 #endif
 };
 
@@ -3206,7 +3206,7 @@ static int parse_line(char *buffer, void *data)
 	if (value_decode == NULL) {
 		ERROR("Value %s decode failed", value);
 	}
-	ret = config->set(key, value_decode ? value_decode: value, plc->conf, NULL);
+	return config->set(key, value_decode ? value_decode: value, plc->conf, NULL);
 #else
 	return config->set(key, value, plc->conf, NULL);
 #endif
@@ -6895,7 +6895,8 @@ static int set_config_init_args(const char *key, const char *value,
 static int get_config_init_args(const char *key, char *retv, int inlen,
 				  struct lxc_conf *c, void *data)
 {
-	int i, len, fulllen = 0;
+	size_t i;
+	int len, fulllen = 0;
 
 	if (!retv)
 		inlen = 0;
@@ -7261,10 +7262,10 @@ static int set_config_selinux_mount_context(const char *key, const char *value,
     struct lxc_conf *lxc_conf, void *data)
 {
 	if (value != NULL && strcmp(value, "unconfined_t") == 0) {
-		return set_config_string_item(&lxc_conf->lsm_se_mount_context, NULL);
+		return set_config_string_item(&lxc_conf->rootfs.lsm_se_mount_context, NULL);
 	}
 
-	return set_config_string_item(&lxc_conf->lsm_se_mount_context, value);
+	return set_config_string_item(&lxc_conf->rootfs.lsm_se_mount_context, value);
 }
 
 static int get_config_console_log_driver(const char *key, char *retv, int inlen,
@@ -7288,7 +7289,7 @@ static int get_config_console_syslog_facility(const char *key, char *retv, int i
 static int get_config_selinux_mount_context(const char *key, char *retv, int inlen,
     struct lxc_conf *c, void *data)
 {
-	return lxc_get_conf_str(retv, inlen, c->lsm_se_mount_context);
+	return lxc_get_conf_str(retv, inlen, c->rootfs.lsm_se_mount_context);
 }
 
 static inline int clr_config_console_log_driver(const char *key,
@@ -7317,8 +7318,8 @@ static inline int clr_config_console_syslog_facility(const char *key,
 static inline int clr_config_selinux_mount_context(const char *key,
     struct lxc_conf *c, void *data)
 {
-	free(c->lsm_se_mount_context);
-	c->lsm_se_mount_context = NULL;
+	free(c->rootfs.lsm_se_mount_context);
+	c->rootfs.lsm_se_mount_context = NULL;
 	return 0;
 }
 #endif
diff --git a/src/lxc/exec_commands.c b/src/lxc/exec_commands.c
index bd81d66..5612109 100644
--- a/src/lxc/exec_commands.c
+++ b/src/lxc/exec_commands.c
@@ -37,6 +37,7 @@
 
 #include "af_unix.h"
 #include "cgroup.h"
+#include "string_utils.h"
 #include "exec_commands.h"
 #include "commands_utils.h"
 #include "conf.h"
@@ -47,8 +48,6 @@
 #include "lxclock.h"
 #include "mainloop.h"
 #include "monitor.h"
-#include "string_utils.h"
-#include "terminal.h"
 #include "utils.h"
 
 lxc_log_define(commands_exec, lxc);
@@ -70,12 +69,7 @@ static int lxc_exec_cmd_rsp_recv(int sock, struct lxc_exec_cmd_rr *cmd)
 	int ret, rspfd;
 	struct lxc_exec_cmd_rsp *rsp = &cmd->rsp;
 
-	/*isulad: add timeout 1s to avoid long block due to [lxc monitor] error*/
-	if (lxc_socket_set_timeout(sock, 1, 1) != 0) {
-		return syserror_ret(-1, "Failed to set timeout");
-	}
-
-	ret = lxc_cmd_rsp_recv_fds(sock, &rspfd, 1, rsp, sizeof(*rsp));
+	ret = lxc_abstract_unix_recv_one_fd_timeout(sock, &rspfd, rsp, sizeof(*rsp), 1000 * 1000);
 	if (ret < 0) {
 		SYSERROR("Failed to receive response for command \"%s\"",
 		        lxc_exec_cmd_str(cmd->req.cmd));
@@ -256,7 +250,7 @@ static int lxc_exec_cmd_process(int fd, struct lxc_exec_cmd_req *req,
 	return cb[req->cmd](fd, req, handler);
 }
 
-static void lxc_exec_cmd_fd_cleanup(int fd, struct lxc_epoll_descr *descr)
+static void lxc_exec_cmd_fd_cleanup(int fd, struct lxc_async_descr *descr)
 {
 	lxc_mainloop_del_handler(descr, fd);
 	close(fd);
@@ -264,7 +258,7 @@ static void lxc_exec_cmd_fd_cleanup(int fd, struct lxc_epoll_descr *descr)
 }
 
 static int lxc_exec_cmd_handler(int fd, uint32_t events, void *data,
-			   struct lxc_epoll_descr *descr)
+			   struct lxc_async_descr *descr)
 {
 	int ret;
 	struct lxc_exec_cmd_req req;
@@ -341,7 +335,7 @@ out_close:
 }
 
 static int lxc_exec_cmd_accept(int fd, uint32_t events, void *data,
-			  struct lxc_epoll_descr *descr)
+			  struct lxc_async_descr *descr)
 {
 	int connection = -1;
 	int opt = 1, ret = -1;
@@ -364,7 +358,8 @@ static int lxc_exec_cmd_accept(int fd, uint32_t events, void *data,
 		goto out_close;
 	}
 
-	ret = lxc_mainloop_add_handler(descr, connection, lxc_exec_cmd_handler, data);
+	ret = lxc_mainloop_add_handler(descr, connection, lxc_exec_cmd_handler, default_cleanup_handler, data,
+								   "exec_cmd_handler");
 	if (ret) {
 		ERROR("Failed to add command handler");
 		goto out_close;
@@ -462,12 +457,12 @@ int lxc_exec_cmd_init(const char *name, const char *lxcpath, const char *suffix)
 }
 #endif
 
-int lxc_exec_cmd_mainloop_add(struct lxc_epoll_descr *descr, struct lxc_exec_command_handler *handler)
+int lxc_exec_cmd_mainloop_add(struct lxc_async_descr *descr, struct lxc_exec_command_handler *handler)
 {
 	int ret;
 	int fd = handler->maincmd_fd;
 
-	ret = lxc_mainloop_add_handler(descr, fd, lxc_exec_cmd_accept, handler);
+	ret = lxc_mainloop_add_handler(descr, fd, lxc_exec_cmd_accept, default_cleanup_handler, handler, "exec_cmd_accept");
 	if (ret < 0) {
 		ERROR("Failed to add handler for command socket");
 		close(fd);
diff --git a/src/lxc/exec_commands.h b/src/lxc/exec_commands.h
index 3ec2a22..ca3a4d6 100644
--- a/src/lxc/exec_commands.h
+++ b/src/lxc/exec_commands.h
@@ -63,11 +63,11 @@ struct lxc_exec_cmd_set_terminal_winch_request {
 	unsigned int width;
 };
 
-struct lxc_epoll_descr;
+struct lxc_async_descr;
 struct lxc_handler;
 
 extern int lxc_exec_cmd_init(const char *name, const char *lxcpath, const char *suffix);
-extern int lxc_exec_cmd_mainloop_add(struct lxc_epoll_descr *descr, struct lxc_exec_command_handler *handler);
+extern int lxc_exec_cmd_mainloop_add(struct lxc_async_descr *descr, struct lxc_exec_command_handler *handler);
 extern int lxc_exec_cmd_set_terminal_winch(const char *name, const char *lxcpath, const char *suffix, unsigned int height, unsigned int width);
 
 #ifdef HAVE_ISULAD
diff --git a/src/lxc/execute.c b/src/lxc/execute.c
index 6a7ae39..2960664 100644
--- a/src/lxc/execute.c
+++ b/src/lxc/execute.c
@@ -18,7 +18,11 @@
 
 lxc_log_define(execute, start);
 
+#ifdef HAVE_ISULAD
+static int execute_start(struct lxc_handler *handler, void* data, int fd)
+#else
 static int execute_start(struct lxc_handler *handler, void* data)
+#endif
 {
 	int argc = 0;
 	struct execute_args *my_args = data;
@@ -40,14 +44,25 @@ static struct lxc_operations execute_start_ops = {
 	.post_start = execute_post_start
 };
 
+#ifdef HAVE_ISULAD
+int lxc_execute(const char *name, char *const argv[], int quiet,
+		struct lxc_handler *handler, const char *lxcpath,
+		bool daemonize, int *error_num, unsigned int start_timeout)
+#else
 int lxc_execute(const char *name, char *const argv[], int quiet,
 		struct lxc_handler *handler, const char *lxcpath,
 		bool daemonize, int *error_num)
+#endif
 {
 	struct execute_args args = {.argv = argv, .quiet = quiet};
 
 	TRACE("Doing lxc_execute");
 	handler->conf->is_execute = true;
+#ifdef HAVE_ISULAD
+	return __lxc_start(handler, &execute_start_ops, &args, lxcpath,
+			   daemonize, error_num, start_timeout);
+#else
 	return __lxc_start(handler, &execute_start_ops, &args, lxcpath,
 			   daemonize, error_num);
+#endif
 }
diff --git a/src/lxc/isulad_utils.c b/src/lxc/isulad_utils.c
index 889d912..38dbe2a 100644
--- a/src/lxc/isulad_utils.c
+++ b/src/lxc/isulad_utils.c
@@ -233,7 +233,7 @@ unsigned long long lxc_get_process_startat(pid_t pid)
     char sbuf[1024] = {0}; /* bufs for stat */
 
     sret = snprintf(filename, sizeof(filename), "/proc/%d/stat", pid);
-    if (sret < 0 || sret >= sizeof(filename)) {
+    if (sret < 0 || (size_t)sret >= sizeof(filename)) {
         ERROR("Failed to sprintf filename");
         goto out;
     }
@@ -317,7 +317,7 @@ bool lxc_process_alive(pid_t pid, unsigned long long start_time)
 		return false;
 
 	sret = snprintf(filename, sizeof(filename), "/proc/%d/stat", pid);
-	if (sret < 0 || sret >= sizeof(filename)) {
+	if (sret < 0 || (size_t)sret >= sizeof(filename)) {
 		ERROR("Failed to sprintf filename");
 		goto out;
 	}
@@ -537,7 +537,7 @@ out:
 ssize_t lxc_write_nointr_for_fifo(int fd, const char *buf, size_t count)
 {
     ssize_t nret = 0;
-    ssize_t nwritten;
+    size_t nwritten;
 
     if (buf == NULL) {
         return -1;
diff --git a/src/lxc/isulad_utils.h b/src/lxc/isulad_utils.h
index 93174ae..3dfa9f7 100644
--- a/src/lxc/isulad_utils.h
+++ b/src/lxc/isulad_utils.h
@@ -5,13 +5,15 @@
  * Author: lifeng
  * Create: 2020-04-11
 ******************************************************************************/
-#ifndef __iSULAD_UTILS_H
-#define __iSULAD_UTILS_H
+#ifndef __ISULAD_UTILS_H
+#define __ISULAD_UTILS_H
 
 #include <stdio.h>
 #include <stdbool.h>
 #include <pwd.h>
 
+#include "compiler.h"
+
 /* isulad: replace space with SPACE_MAGIC_STR */
 #define SPACE_MAGIC_STR "[#)"
 
@@ -97,7 +99,7 @@ __hidden extern bool lxc_process_alive(pid_t pid, unsigned long long start_time)
 
 __hidden extern bool is_non_negative_num(const char *s);
 
-__hidden int util_getpwent_r(FILE *stream, struct passwd *resbuf, char *buffer, size_t buflen, struct passwd **result);
+__hidden extern int util_getpwent_r(FILE *stream, struct passwd *resbuf, char *buffer, size_t buflen, struct passwd **result);
 
 __hidden extern ssize_t lxc_write_nointr_for_fifo(int fd, const char *buf, size_t count);
 
diff --git a/src/lxc/lsm/lsm.c b/src/lxc/lsm/lsm.c
index d9380c4..db4bb0c 100644
--- a/src/lxc/lsm/lsm.c
+++ b/src/lxc/lsm/lsm.c
@@ -19,6 +19,10 @@ __hidden extern struct lsm_ops *lsm_apparmor_ops_init(void);
 __hidden extern struct lsm_ops *lsm_selinux_ops_init(void);
 __hidden extern struct lsm_ops *lsm_nop_ops_init(void);
 
+#ifdef HAVE_ISULAD
+static struct lsm_ops *ops_instance = NULL;
+#endif
+
 struct lsm_ops *lsm_init_static(void)
 {
 	struct lsm_ops *ops = NULL;
@@ -35,6 +39,30 @@ struct lsm_ops *lsm_init_static(void)
 	if (!ops)
 		ops = lsm_nop_ops_init();
 
+#ifdef HAVE_ISULAD
+	ops_instance = ops;
+#endif
+
 	INFO("Initialized LSM security driver %s", ops->name);
 	return ops;
 }
+
+#ifdef HAVE_ISULAD
+int lsm_file_label_set(const char *path, const char *label)
+{
+	if (!ops_instance) {
+		ERROR("LSM driver not inited");
+		return -1;
+	}
+	return ops_instance->file_label_set(path, label);
+}
+
+int lsm_relabel(const char *path, const char *label, bool share)
+{
+	if (!ops_instance) {
+		ERROR("LSM driver not inited");
+		return -1;
+	}
+	return ops_instance->relabel(path, label, share);
+}
+#endif
diff --git a/src/lxc/lsm/lsm.h b/src/lxc/lsm/lsm.h
index 93e1a99..571a92d 100644
--- a/src/lxc/lsm/lsm.h
+++ b/src/lxc/lsm/lsm.h
@@ -42,4 +42,9 @@ struct lsm_ops {
 
 __hidden extern struct lsm_ops *lsm_init_static(void);
 
+#ifdef HAVE_ISULAD
+__hidden extern int lsm_file_label_set(const char *path, const char *label);
+__hidden extern int lsm_relabel(const char *path, const char *label, bool share);
+#endif
+
 #endif /* __LXC_LSM_H */
diff --git a/src/lxc/lsm/selinux.c b/src/lxc/lsm/selinux.c
index 5190110..0bdfcff 100644
--- a/src/lxc/lsm/selinux.c
+++ b/src/lxc/lsm/selinux.c
@@ -272,7 +272,7 @@ static int recurse_set_file_label(const char *basePath, const char *label)
 			continue;
 		} else {
 			int nret = snprintf(base, sizeof(base), "%s/%s", basePath, ptr->d_name);
-			if (nret < 0 || nret >= sizeof(base)) {
+			if (nret < 0 || (size_t)nret >= sizeof(base)) {
 				ERROR("Failed to get path");
 				return -1;
 			}
diff --git a/src/lxc/lxc.h b/src/lxc/lxc.h
index 879e899..74c8aa8 100644
--- a/src/lxc/lxc.h
+++ b/src/lxc/lxc.h
@@ -39,8 +39,13 @@ struct lxc_handler;
  * @daemonize    : whether or not the container is daemonized
  * Returns 0 on success, < 0 otherwise
  */
+#ifdef HAVE_ISULAD
+__hidden extern int lxc_start(char *const argv[], struct lxc_handler *handler, const char *lxcpath,
+			      bool daemonize, int *error_num, unsigned int start_timeout);
+#else
 __hidden extern int lxc_start(char *const argv[], struct lxc_handler *handler, const char *lxcpath,
 			      bool daemonize, int *error_num);
+#endif
 
 /*
  * Start the specified command inside an application container
@@ -51,9 +56,15 @@ __hidden extern int lxc_start(char *const argv[], struct lxc_handler *handler, c
  * @daemonize    : whether or not the container is daemonized
  * Returns 0 on success, < 0 otherwise
  */
+#ifdef HAVE_ISULAD
+__hidden extern int lxc_execute(const char *name, char *const argv[], int quiet,
+				struct lxc_handler *handler, const char *lxcpath, bool daemonize,
+				int *error_num, unsigned int start_timeout);
+#else
 __hidden extern int lxc_execute(const char *name, char *const argv[], int quiet,
 				struct lxc_handler *handler, const char *lxcpath, bool daemonize,
 				int *error_num);
+#endif
 
 /*
  * Close the fd associated with the monitoring
diff --git a/src/lxc/lxccontainer.c b/src/lxc/lxccontainer.c
index d4495f7..5720cf7 100644
--- a/src/lxc/lxccontainer.c
+++ b/src/lxc/lxccontainer.c
@@ -6100,7 +6100,11 @@ WRAP_API_1(bool, lxcapi_get_container_metrics, struct lxc_container_metrics *)
 
 #endif
 
+#ifdef HAVE_ISULAD
+static struct lxc_container *do_lxc_container_new(const char *name, const char *configpath, bool load_config)
+#else
 struct lxc_container *lxc_container_new(const char *name, const char *configpath)
+#endif
 {
 	struct lxc_container *c;
 	size_t len;
diff --git a/src/lxc/mainloop.c b/src/lxc/mainloop.c
index 765240e..9522b7d 100644
--- a/src/lxc/mainloop.c
+++ b/src/lxc/mainloop.c
@@ -534,7 +534,7 @@ void lxc_mainloop_close(struct lxc_async_descr *descr)
 }
 
 #ifdef HAVE_ISULAD
-int isulad_safe_mainloop(struct lxc_epoll_descr *descr, int timeout_ms)
+int isulad_safe_mainloop(struct lxc_async_descr *descr, int timeout_ms)
 {
     int ret;
 
diff --git a/src/lxc/mainloop.h b/src/lxc/mainloop.h
index e8ce082..f485a1f 100644
--- a/src/lxc/mainloop.h
+++ b/src/lxc/mainloop.h
@@ -66,7 +66,7 @@ __hidden extern void lxc_mainloop_close(struct lxc_async_descr *descr);
 define_cleanup_function(struct lxc_async_descr *, lxc_mainloop_close);
 
 #ifdef HAVE_ISULAD
-__hidden extern int isulad_safe_mainloop(struct lxc_epoll_descr *descr, int timeout_ms);
+__hidden extern int isulad_safe_mainloop(struct lxc_async_descr *descr, int timeout_ms);
 #endif
 
 #endif
diff --git a/src/lxc/seccomp.c b/src/lxc/seccomp.c
index f0fa297..d952beb 100644
--- a/src/lxc/seccomp.c
+++ b/src/lxc/seccomp.c
@@ -699,21 +699,33 @@ static int parse_config_v2(FILE *f, char *line, size_t *line_bufsz, struct lxc_c
 		ctx.architectures[0] = SCMP_ARCH_X86;
 		ctx.contexts[0] = get_new_ctx(lxc_seccomp_arch_i386,
 					      default_policy_action,
+#ifdef HAVE_ISULAD
+					      &ctx.architectures[0]);
+#else
 					      &ctx.needs_merge[0]);
+#endif
 		if (!ctx.contexts[0])
 			goto bad;
 
 		ctx.architectures[1] = SCMP_ARCH_X32;
 		ctx.contexts[1] = get_new_ctx(lxc_seccomp_arch_x32,
 					      default_policy_action,
+#ifdef HAVE_ISULAD
+					      &ctx.architectures[1]);
+#else
 					      &ctx.needs_merge[1]);
+#endif
 		if (!ctx.contexts[1])
 			goto bad;
 
 		ctx.architectures[2] = SCMP_ARCH_X86_64;
 		ctx.contexts[2] = get_new_ctx(lxc_seccomp_arch_amd64,
 					      default_policy_action,
+#ifdef HAVE_ISULAD
+					      &ctx.architectures[2]);
+#else
 					      &ctx.needs_merge[2]);
+#endif
 		if (!ctx.contexts[2])
 			goto bad;
 #ifdef SCMP_ARCH_PPC
@@ -723,14 +735,22 @@ static int parse_config_v2(FILE *f, char *line, size_t *line_bufsz, struct lxc_c
 		ctx.architectures[0] = SCMP_ARCH_PPC;
 		ctx.contexts[0] = get_new_ctx(lxc_seccomp_arch_ppc,
 					      default_policy_action,
+#ifdef HAVE_ISULAD
+					      &ctx.architectures[0]);
+#else
 					      &ctx.needs_merge[0]);
+#endif
 		if (!ctx.contexts[0])
 			goto bad;
 
 		ctx.architectures[2] = SCMP_ARCH_PPC64;
 		ctx.contexts[2] = get_new_ctx(lxc_seccomp_arch_ppc64,
 					      default_policy_action,
+#ifdef HAVE_ISULAD
+					      &ctx.architectures[2]);
+#else
 					      &ctx.needs_merge[2]);
+#endif
 		if (!ctx.contexts[2])
 			goto bad;
 #endif
@@ -741,7 +761,11 @@ static int parse_config_v2(FILE *f, char *line, size_t *line_bufsz, struct lxc_c
 		ctx.architectures[0] = SCMP_ARCH_ARM;
 		ctx.contexts[0] = get_new_ctx(lxc_seccomp_arch_arm,
 					      default_policy_action,
+#ifdef HAVE_ISULAD
+					      &ctx.architectures[0]);
+#else
 					      &ctx.needs_merge[0]);
+#endif
 		if (!ctx.contexts[0])
 			goto bad;
 
@@ -749,7 +773,11 @@ static int parse_config_v2(FILE *f, char *line, size_t *line_bufsz, struct lxc_c
 		ctx.architectures[2] = SCMP_ARCH_AARCH64;
 		ctx.contexts[2] = get_new_ctx(lxc_seccomp_arch_arm64,
 					      default_policy_action,
+#ifdef HAVE_ISULAD
+					      &ctx.architectures[2]);
+#else
 					      &ctx.needs_merge[2]);
+#endif
 		if (!ctx.contexts[2])
 			goto bad;
 #endif
@@ -761,21 +789,33 @@ static int parse_config_v2(FILE *f, char *line, size_t *line_bufsz, struct lxc_c
 		ctx.architectures[0] = SCMP_ARCH_MIPS;
 		ctx.contexts[0] = get_new_ctx(lxc_seccomp_arch_mips,
 					      default_policy_action,
+#ifdef HAVE_ISULAD
+					      &ctx.architectures[0]);
+#else
 					      &ctx.needs_merge[0]);
+#endif
 		if (!ctx.contexts[0])
 			goto bad;
 
 		ctx.architectures[1] = SCMP_ARCH_MIPS64N32;
 		ctx.contexts[1] = get_new_ctx(lxc_seccomp_arch_mips64n32,
 					      default_policy_action,
+#ifdef HAVE_ISULAD
+					      &ctx.architectures[1]);
+#else
 					      &ctx.needs_merge[1]);
+#endif
 		if (!ctx.contexts[1])
 			goto bad;
 
 		ctx.architectures[2] = SCMP_ARCH_MIPS64;
 		ctx.contexts[2] = get_new_ctx(lxc_seccomp_arch_mips64,
 					      default_policy_action,
+#ifdef HAVE_ISULAD
+					      &ctx.architectures[2]);
+#else
 					      &ctx.needs_merge[2]);
+#endif
 		if (!ctx.contexts[2])
 			goto bad;
 	} else if (native_arch == lxc_seccomp_arch_mipsel64) {
@@ -784,21 +824,33 @@ static int parse_config_v2(FILE *f, char *line, size_t *line_bufsz, struct lxc_c
 		ctx.architectures[0] = SCMP_ARCH_MIPSEL;
 		ctx.contexts[0] = get_new_ctx(lxc_seccomp_arch_mipsel,
 					      default_policy_action,
+#ifdef HAVE_ISULAD
+					      &ctx.architectures[0]);
+#else
 					      &ctx.needs_merge[0]);
+#endif
 		if (!ctx.contexts[0])
 			goto bad;
 
 		ctx.architectures[1] = SCMP_ARCH_MIPSEL64N32;
 		ctx.contexts[1] = get_new_ctx(lxc_seccomp_arch_mipsel64n32,
 					      default_policy_action,
+#ifdef HAVE_ISULAD
+					      &ctx.architectures[1]);
+#else
 					      &ctx.needs_merge[1]);
+#endif
 		if (!ctx.contexts[1])
 			goto bad;
 
 		ctx.architectures[2] = SCMP_ARCH_MIPSEL64;
 		ctx.contexts[2] = get_new_ctx(lxc_seccomp_arch_mipsel64,
 					      default_policy_action,
+#ifdef HAVE_ISULAD
+					      &ctx.architectures[2]);
+#else
 					      &ctx.needs_merge[2]);
+#endif
 		if (!ctx.contexts[2])
 			goto bad;
 #endif
diff --git a/src/lxc/start.c b/src/lxc/start.c
index 70af128..ff9a3fa 100644
--- a/src/lxc/start.c
+++ b/src/lxc/start.c
@@ -2067,6 +2067,9 @@ static int lxc_spawn(struct lxc_handler *handler)
 	const char *name = handler->name;
 	struct lxc_conf *conf = handler->conf;
 	struct cgroup_ops *cgroup_ops = handler->cgroup_ops;
+#ifdef HAVE_ISULAD
+	const char *lxcpath = handler->lxcpath;
+#endif
 
 	id_map = &conf->id_map;
 	wants_to_map_ids = !list_empty(id_map);
@@ -2364,6 +2367,30 @@ static int lxc_spawn(struct lxc_handler *handler)
 		goto out_delete_net;
 	}
 
+#ifdef HAVE_ISULAD
+	if (!lxc_sync_wait_child(handler, START_SYNC_OCI_PRESTART_HOOK))
+		goto out_delete_net;
+
+	/* isulad: Run oci prestart hook at here */
+	ret = run_oci_hooks(name, "oci-prestart", conf, lxcpath);
+	if (ret < 0) {
+		ERROR("Failed to run oci prestart hooks");
+		goto out_delete_net;
+	}
+
+	if (START_TIMEOUT == global_timeout_state) {
+		lxc_write_error_message(conf->errpipe[1], "Starting the container \"%s\" timeout.", name);
+		ERROR("Starting the container \"%s\" timeout.", name);
+		goto out_delete_net;
+	}
+
+       /* Tell the child to continue its initialization. We'll get
+        * START_SYNC_POST_OCI_PRESTART_HOOK when it is ready for us to run oci prestart hooks.
+        */
+       if (lxc_sync_wake_child(handler, START_SYNC_POST_OCI_PRESTART_HOOK))
+               goto out_delete_net;
+#endif
+
 	if (!lxc_sync_wait_child(handler, START_SYNC_CGROUP_LIMITS))
 		goto out_delete_net;
 
@@ -2394,27 +2421,6 @@ static int lxc_spawn(struct lxc_handler *handler)
 		goto out_delete_net;
 	}
 
-#ifdef HAVE_ISULAD
-	/* isulad: Run oci prestart hook at here */
-	ret = run_oci_hooks(name, "oci-prestart", conf, lxcpath);
-	if (ret < 0) {
-		ERROR("Failed to run oci prestart hooks");
-		goto out_delete_net;
-	}
-
-	if (START_TIMEOUT == global_timeout_state) {
-		lxc_write_error_message(conf->errpipe[1], "Starting the container \"%s\" timeout.", name);
-		ERROR("Starting the container \"%s\" timeout.", name);
-		goto out_delete_net;
-	}
-
-       /* Tell the child to continue its initialization. We'll get
-        * LXC_SYNC_POST_OCI_PRESTART_HOOK when it is ready for us to run oci prestart hooks.
-        */
-       if (lxc_sync_barrier_child(handler, LXC_SYNC_POST_OCI_PRESTART_HOOK))
-               goto out_delete_net;
-#endif
-
 	if (!lxc_sync_wake_child(handler, START_SYNC_FDS))
 		goto out_delete_net;
 
@@ -2943,7 +2949,7 @@ static int clean_resource_set_env(struct lxc_handler *handler)
 	const char *name = handler->name;
 	struct lxc_conf *conf = handler->conf;
 	char bufstr[PATH_MAX + 1];
-	int i = 0;
+	size_t i = 0;
 	int j = 0;
 	int len = 2; //set "LXC_PID" and "LXC_CGNS_AWARE"
 
@@ -3039,7 +3045,6 @@ static struct lxc_handler *lxc_init_clean_handler(char *name, char *lxcpath, str
 	handler->data_sock[0] = handler->data_sock[1] = -1;
 	handler->conf = conf;
 	handler->lxcpath = lxcpath;
-	handler->pinfd = -1;
 	handler->sigfd = -EBADF;
 	handler->pidfd = -EBADF;
 	handler->init_died = false;
@@ -3047,7 +3052,7 @@ static struct lxc_handler *lxc_init_clean_handler(char *name, char *lxcpath, str
 	handler->pid = pid;
 	handler->state_socket_pair[0] = handler->state_socket_pair[1] = -1;
 	if (handler->conf->reboot == REBOOT_NONE)
-		lxc_list_init(&handler->conf->state_clients);
+		INIT_LIST_HEAD(&handler->conf->state_clients);
 
 	for (i = 0; i < LXC_NS_MAX; i++)
 		handler->nsfd[i] = -1;
@@ -3091,14 +3096,13 @@ static struct lxc_handler *lxc_init_pids_handler(char *name, char *lxcpath, stru
 	handler->data_sock[0] = handler->data_sock[1] = -1;
 	handler->conf = conf;
 	handler->lxcpath = lxcpath;
-	handler->pinfd = -1;
 	handler->sigfd = -EBADF;
 	handler->init_died = false;
 	handler->state_socket_pair[0] = handler->state_socket_pair[1] = -1;
 	handler->monitor_status_fd = -EBADF;
 	handler->pidfd = -EBADF;
 	if (handler->conf->reboot == REBOOT_NONE)
-		lxc_list_init(&handler->conf->state_clients);
+		INIT_LIST_HEAD(&handler->conf->state_clients);
 
 	for (i = 0; i < LXC_NS_MAX; i++)
 		handler->nsfd[i] = -1;
diff --git a/src/lxc/sync.c b/src/lxc/sync.c
index 1075d98..f156809 100644
--- a/src/lxc/sync.c
+++ b/src/lxc/sync.c
@@ -70,6 +70,12 @@ static inline const char *start_sync_to_string(int state)
 		return "cgroup-limits";
 	case START_SYNC_IDMAPPED_MOUNTS:
 		return "idmapped-mounts";
+#ifdef HAVE_ISULAd
+	case START_SYNC_OCI_PRESTART_HOOK:
+		return "oci-prestart-hook";
+	case START_SYNC_POST_OCI_PRESTART_HOOK:
+		return "post-oci-prestart-hook";
+#endif
 	case START_SYNC_FDS:
 		return "fds";
 	case START_SYNC_READY_START:
diff --git a/src/lxc/sync.h b/src/lxc/sync.h
index ef03e1e..6802d32 100644
--- a/src/lxc/sync.h
+++ b/src/lxc/sync.h
@@ -21,12 +21,13 @@ enum /* start */ {
 	START_SYNC_POST_CONFIGURE	=  2,
 	START_SYNC_IDMAPPED_MOUNTS	=  3,
 #ifdef HAVE_ISULAD
-	LXC_SYNC_OCI_PRESTART_HOOK = 4,
-	START_SYNC_CGROUP_LIMITS	=  5,
-	START_SYNC_FDS			=  6,
-	START_SYNC_READY_START		=  7,
-	START_SYNC_RESTART		=  8,
-	START_SYNC_POST_RESTART		=  9,
+	START_SYNC_OCI_PRESTART_HOOK = 4,
+	START_SYNC_POST_OCI_PRESTART_HOOK = 5,
+	START_SYNC_CGROUP_LIMITS	=  6,
+	START_SYNC_FDS			=  7,
+	START_SYNC_READY_START		=  8,
+	START_SYNC_RESTART		=  9,
+	START_SYNC_POST_RESTART		=  10,
 #else
 	START_SYNC_CGROUP_LIMITS	=  4,
 	START_SYNC_FDS			=  5,
diff --git a/src/lxc/terminal.c b/src/lxc/terminal.c
index 8da00a9..de7ea4f 100644
--- a/src/lxc/terminal.c
+++ b/src/lxc/terminal.c
@@ -204,11 +204,11 @@ int lxc_set_terminal_winsz(struct lxc_terminal *terminal, unsigned int height, u
 	int ret = 0;
 	struct winsize wsz;
 
-	if (terminal->ptmx < 0) {
+	if (terminal->ptx < 0) {
 		return 0;
 	}
 
-	ret = ioctl(terminal->ptmx, TIOCGWINSZ, &wsz);
+	ret = ioctl(terminal->ptx, TIOCGWINSZ, &wsz);
 	if (ret < 0) {
 		WARN("Failed to get window size");
 		return -1;
@@ -216,7 +216,7 @@ int lxc_set_terminal_winsz(struct lxc_terminal *terminal, unsigned int height, u
 	wsz.ws_col = width;
 	wsz.ws_row = height;
 
-	ret = ioctl(terminal->ptmx, TIOCSWINSZ, &wsz);
+	ret = ioctl(terminal->ptx, TIOCSWINSZ, &wsz);
 	if (ret < 0)
 		WARN("Failed to set window size");
 	else
@@ -299,6 +299,359 @@ static int lxc_terminal_rotate_log_file(struct lxc_terminal *terminal)
 }
 
 #ifdef HAVE_ISULAD
+/* get time buffer */
+static bool get_time_buffer(struct timespec *timestamp, char *timebuffer,
+                            size_t maxsize)
+{
+	struct tm tm_utc = { 0 };
+	int32_t nanos = 0;
+	time_t seconds;
+	size_t len = 0;
+	int ret = 0;
+
+	if (!timebuffer || !maxsize) {
+		return false;
+	}
+
+	seconds = (time_t)timestamp->tv_sec;
+	gmtime_r(&seconds, &tm_utc);
+	strftime(timebuffer, maxsize, "%Y-%m-%dT%H:%M:%S", &tm_utc);
+
+	nanos = (int32_t)timestamp->tv_nsec;
+	len = strlen(timebuffer);
+	ret = snprintf(timebuffer + len, (maxsize - len), ".%09dZ", nanos);
+	if (ret < 0 || (size_t)ret >= (maxsize - len)) {
+		return false;
+	}
+
+	return true;
+}
+
+/* get now time buffer */
+static bool get_now_time_buffer(char *timebuffer, size_t maxsize)
+{
+	int err = 0;
+	struct timespec ts;
+
+	err = clock_gettime(CLOCK_REALTIME, &ts);
+	if (err != 0) {
+		ERROR("failed to get time");
+		return false;
+	}
+
+	return get_time_buffer(&ts, timebuffer, maxsize);
+}
+
+static int isulad_lxc_terminal_rotate_write_data(struct lxc_terminal *terminal, const char *buf,
+                int bytes_read)
+{
+	int ret;
+	struct stat st;
+	int64_t space_left = -1;
+
+	if (terminal->log_fd < 0)
+		return 0;
+
+	/* A log size <= 0 means that there's no limit on the size of the log
+	 * file at which point we simply ignore whether the log is supposed to
+	 * be rotated or not.
+	 */
+	if (terminal->log_size <= 0)
+		return lxc_write_nointr(terminal->log_fd, buf, bytes_read);
+
+	/* Get current size of the log file. */
+	ret = fstat(terminal->log_fd, &st);
+	if (ret < 0) {
+		SYSERROR("Failed to stat the terminal log file descriptor");
+		return -1;
+	}
+
+	/* handle non-regular files */
+	if ((st.st_mode & S_IFMT) != S_IFREG) {
+		/* This isn't a regular file. so rotating the file seems a
+		 * dangerous thing to do, size limits are also very
+		 * questionable. Let's not risk anything and tell the user that
+		 * he's requesting us to do weird stuff.
+		 */
+		if (terminal->log_rotate > 0 || terminal->log_size > 0)
+			return -EINVAL;
+
+		/* I mean, sure log wherever you want to. */
+		return lxc_write_nointr(terminal->log_fd, buf, bytes_read);
+	}
+
+	space_left = terminal->log_size - st.st_size;
+
+	/* User doesn't want to rotate the log file and there's no more space
+	 * left so simply truncate it.
+	 */
+	if (space_left <= 0 && terminal->log_rotate <= 0) {
+		ret = lxc_terminal_truncate_log_file(terminal);
+		if (ret < 0)
+			return ret;
+
+		if ((uint64_t)bytes_read <= terminal->log_size)
+			return lxc_write_nointr(terminal->log_fd, buf, bytes_read);
+
+		/* Write as much as we can into the buffer and loose the rest. */
+		return lxc_write_nointr(terminal->log_fd, buf, terminal->log_size);
+	}
+
+	/* There's enough space left. */
+	if (bytes_read <= space_left)
+		return lxc_write_nointr(terminal->log_fd, buf, bytes_read);
+
+	/* There'd be more to write but we aren't instructed to rotate the log
+	 * file so simply return. There's no error on our side here.
+	 */
+	if (terminal->log_rotate > 0)
+		ret = lxc_terminal_rotate_log_file(terminal);
+	else
+		ret = lxc_terminal_truncate_log_file(terminal);
+	if (ret < 0)
+		return ret;
+
+	if (terminal->log_size < (uint64_t)bytes_read) {
+		/* Well, this is unfortunate because it means that there is more
+		 * to write than the user has granted us space. There are
+		 * multiple ways to handle this but let's use the simplest one:
+		 * write as much as we can, tell the user that there was more
+		 * stuff to write and move on.
+		 * Note that this scenario shouldn't actually happen with the
+		 * standard pty-based terminal that LXC allocates since it will
+		 * be switched into raw mode. In raw mode only 1 byte at a time
+		 * should be read and written.
+		 */
+		WARN("Size of terminal log file is smaller than the bytes to write");
+		ret = lxc_write_nointr(terminal->log_fd, buf, terminal->log_size);
+		if (ret < 0)
+			return -1;
+		bytes_read -= ret;
+		return bytes_read;
+	}
+
+	/* Yay, we made it. */
+	ret = lxc_write_nointr(terminal->log_fd, buf, bytes_read);
+	if (ret < 0)
+		return -1;
+	bytes_read -= ret;
+	return bytes_read;
+}
+
+static ssize_t isulad_logger_json_write(struct lxc_terminal *terminal, const char *type, const char *buf,
+                                int bytes_read)
+{
+	logger_json_file *msg = NULL;
+	ssize_t ret = -1;
+	size_t len;
+	char *json = NULL;
+	char timebuffer[64] = { 0 };
+	parser_error err = NULL;
+	struct parser_context ctx = { GEN_OPTIONS_SIMPLIFY | GEN_OPTIONS_NOT_VALIDATE_UTF8, stderr };
+
+	if (bytes_read < 0 || bytes_read >= INT_MAX) {
+		return -1;
+	}
+	msg = calloc(sizeof(logger_json_file), 1);
+	if (msg == NULL) {
+		return -errno;
+	}
+	msg->log = calloc(bytes_read, 1);
+	if (!msg->log) {
+		goto cleanup;
+	}
+	memcpy(msg->log, buf, bytes_read);
+	msg->log_len = bytes_read;
+	msg->stream = type ? safe_strdup(type) : safe_strdup("stdout");
+
+	get_now_time_buffer(timebuffer, sizeof(timebuffer));
+	msg->time = safe_strdup(timebuffer);
+
+	json = logger_json_file_generate_json(msg, &ctx, &err);
+	if (!json) {
+		ERROR("Failed to generate json: %s", err);
+		goto cleanup;
+	}
+	len = strlen(json);
+	json[len] = '\n';
+	ret = isulad_lxc_terminal_rotate_write_data(terminal, json, len + 1);
+cleanup:
+	free(json);
+	free_logger_json_file(msg);
+	free(err);
+	return ret;
+}
+
+static inline bool is_syslog(const char *driver)
+{
+	if (driver == NULL) {
+		return false;
+	}
+
+	return (strcmp("syslog", driver) == 0);
+}
+
+static ssize_t isulad_logger_syslog_write(struct lxc_terminal *terminal, const char *buf)
+{
+        syslog(LOG_INFO, "%s", buf);
+        return 0;
+}
+
+static inline ssize_t isulad_logger_write(struct lxc_terminal *terminal, const char *type, const char *buf,
+                                int bytes_read)
+{
+        if (is_syslog(terminal->log_driver)) {
+                return isulad_logger_syslog_write(terminal, buf);
+        }
+
+        return isulad_logger_json_write(terminal, type, buf, bytes_read);
+}
+
+static int isulad_lxc_terminal_write_log_file(struct lxc_terminal *terminal, const char *type, char *buf,
+                                       int bytes_read)
+{
+#define __BUF_CACHE_SIZE (16 * LXC_TERMINAL_BUFFER_SIZE)
+	static char cache[__BUF_CACHE_SIZE];
+	static int size = 0;
+	int upto, index;
+	int begin = 0, buf_readed = 0,  buf_left = 0;
+	int ret;
+
+	if (buf != NULL && bytes_read > 0) {
+		/* Work out how much more data we are okay with reading this time. */
+		upto = size + bytes_read;
+		if (upto > __BUF_CACHE_SIZE) {
+			upto = __BUF_CACHE_SIZE;
+		}
+
+		if (upto > size) {
+			buf_readed = upto - size;
+			memcpy(cache + size, buf, buf_readed);
+			buf_left = bytes_read - buf_readed;
+			size += buf_readed;
+		}
+	}
+
+	// If we have no data to log, and there's no more coming, we're done.
+	if (size == 0)
+		return 0;
+
+	// Break up the data that we've buffered up into lines, and log each in turn.
+	for (index = 0; index < size; index++) {
+		if (cache[index] == '\n') {
+			ret = isulad_logger_write(terminal, type, cache + begin, index - begin + 1);
+			if (ret < 0) {
+				WARN("Failed to log msg");
+			}
+			begin = index + 1;
+		}
+	}
+	/* If there's no more coming, or the buffer is full but
+	 * has no newlines, log whatever we haven't logged yet,
+	 * noting that it's a partial log line. */
+	if (buf == NULL || (begin == 0 && size == __BUF_CACHE_SIZE)) {
+		if (begin < size) {
+			ret = isulad_logger_write(terminal, type, cache + begin, size - begin);
+			if (ret < 0) {
+				WARN("Failed to log msg");
+			}
+			begin = 0;
+			size = 0;
+		}
+		if (buf == NULL) {
+			return 0;
+		}
+	}
+	/* Move any unlogged data to the front of the buffer in preparation for another read. */
+	if (begin > 0) {
+		memcpy(cache, cache + begin, size - begin);
+		size -= begin;
+	}
+	/* Move left data to cache buffer */
+	if (buf_left > 0) {
+		memcpy(cache + size, buf + buf_readed, buf_left);
+		size += buf_left;
+	}
+	return 0;
+}
+
+/* isulad: forward data to all fifos */
+static void lxc_forward_data_to_fifo(struct lxc_list *list, bool is_err, const char *buf, int r)
+{
+	struct lxc_list *it  = NULL;
+	struct lxc_list *next = NULL;
+	struct lxc_fifos_fd *elem = NULL;
+	ssize_t w = 0;
+
+	lxc_list_for_each_safe(it, list, next) {
+		elem = it->elem;
+		if (is_err) {
+			if (elem->err_fd >= 0) {
+				w = lxc_write_nointr_for_fifo(elem->err_fd, buf, r);
+				if (w != r) {
+					WARN("Failed to write to fifo fd %d with error: %s", elem->err_fd, strerror(errno));
+				}
+			}
+		} else {
+			if (elem->out_fd >= 0) {
+				w = lxc_write_nointr_for_fifo(elem->out_fd, buf, r);
+				if (w != r) {
+					WARN("Failed to write to fifo fd %d with error: %s", elem->out_fd, strerror(errno));
+				}
+			}
+		}
+	}
+
+	return;
+}
+
+/* isulad: judge the fd whether is fifo */
+static bool lxc_terminal_is_fifo(int fd, struct lxc_list *list)
+{
+	struct lxc_list *it = NULL;
+	struct lxc_list *next = NULL;
+	struct lxc_fifos_fd *elem = NULL;
+
+	lxc_list_for_each_safe(it, list, next) {
+		elem = it->elem;
+		if (elem->in_fd == fd)
+			return true;
+	}
+
+	return false;
+}
+
+/* isulad: if fd == -1, means delete all the fifos*/
+int lxc_terminal_delete_fifo(int fd, struct lxc_list *list)
+{
+	struct lxc_list *it = NULL;
+	struct lxc_list *next = NULL;
+	struct lxc_fifos_fd *elem = NULL;
+
+	lxc_list_for_each_safe(it, list, next) {
+		elem = it->elem;
+		if (elem->in_fd == fd || -1 == fd) {
+			INFO("Delete fifo fd %d", fd);
+			lxc_list_del(it);
+			if (elem->in_fifo)
+				free(elem->in_fifo);
+			if (elem->out_fifo)
+				free(elem->out_fifo);
+			if (elem->err_fifo)
+				free(elem->err_fifo);
+			if (elem->in_fd >= 0)
+				close(elem->in_fd);
+			if (elem->out_fd >= 0)
+				close(elem->out_fd);
+			if (elem->err_fd >= 0)
+				close(elem->err_fd);
+			free(elem);
+		}
+	}
+
+	return 0;
+}
+
 static int do_isulad_io(int fd, struct lxc_terminal *terminal)
 {
 	char buf[LXC_TERMINAL_BUFFER_SIZE];
@@ -373,7 +726,6 @@ static int do_isulad_io(int fd, struct lxc_terminal *terminal)
 static int isulad_io_handler(int fd, uint32_t events, void *data,
 				       struct lxc_async_descr *descr)
 {
-	struct lxc_terminal *terminal = data;
 	int ret;
 
 	ret = do_isulad_io(fd, data);
@@ -491,7 +843,11 @@ static int lxc_terminal_write_log_file(struct lxc_terminal *terminal, char *buf,
 }
 #endif
 
+#ifdef HAVE_ISULAD
+static int lxc_terminal_ptx_io(struct lxc_terminal *terminal, int fd)
+#else
 static int lxc_terminal_ptx_io(struct lxc_terminal *terminal)
+#endif
 {
 	char buf[LXC_TERMINAL_BUFFER_SIZE];
 	int r, w, w_log, w_rbuf;
@@ -576,7 +932,11 @@ static int lxc_terminal_ptx_io_handler(int fd, uint32_t events, void *data,
 	struct lxc_terminal *terminal = data;
 	int ret;
 
+#ifdef HAVE_ISULAD
+	ret = lxc_terminal_ptx_io(data, fd);
+#else
 	ret = lxc_terminal_ptx_io(data);
+#endif
 	if (ret < 0)
 		return log_info(LXC_MAINLOOP_CLOSE,
 				"Terminal client on fd %d has exited",
@@ -1408,7 +1768,7 @@ int lxc_terminal_add_fifos(struct lxc_conf *conf, const char *fifonames)
 	}
 
 	if (lxc_mainloop_add_handler(terminal->descr, fifofd_in,
-	                             lxc_terminal_io_cb, terminal)) {
+	                             lxc_terminal_ptx_cb, default_cleanup_handler, terminal, "fifofd_in")) {
 		ERROR("console fifo not added to mainloop");
 		lxc_terminal_delete_fifo(fifofd_in, &terminal->fifos);
 		ret = -1;
@@ -1599,6 +1959,7 @@ int lxc_terminal_parent(struct lxc_conf *conf)
 	return lxc_terminal_map_ids(conf, &conf->console);
 }
 
+#ifndef HAVE_ISULAD
 static int lxc_terminal_create_native(const char *name, const char *lxcpath,
 				      struct lxc_terminal *terminal)
 {
@@ -1627,6 +1988,7 @@ static int lxc_terminal_create_native(const char *name, const char *lxcpath,
 
 	return 0;
 }
+#endif
 
 int lxc_terminal_create(const char *name, const char *lxcpath,
 			struct lxc_conf *conf, struct lxc_terminal *terminal)
@@ -1635,6 +1997,7 @@ int lxc_terminal_create(const char *name, const char *lxcpath,
 	if (!lxc_terminal_create_native(name, lxcpath, terminal))
 		return 0;
 #else
+	int ret;
 	/* isulad: open default fifos */
 	ret = lxc_terminal_fifo_default(terminal);
 	if (ret < 0) {
diff --git a/src/lxc/tools/lxc_ls.c b/src/lxc/tools/lxc_ls.c
index 86a453d..505ed95 100644
--- a/src/lxc/tools/lxc_ls.c
+++ b/src/lxc/tools/lxc_ls.c
@@ -1004,7 +1004,7 @@ static int my_parser(struct lxc_arguments *args, int c, char *arg)
 }
 
 #ifdef HAVE_ISULAD
-static int ls_get_wrapper(void *wrap, int msgfd);
+static int ls_get_wrapper(void *wrap, int msgfd)
 #else
 static int ls_get_wrapper(void *wrap)
 #endif
diff --git a/src/lxc/utils.c b/src/lxc/utils.c
index 25cb0d1..397638e 100644
--- a/src/lxc/utils.c
+++ b/src/lxc/utils.c
@@ -37,6 +37,9 @@
 #include "process_utils.h"
 #include "syscall_wrappers.h"
 #include "utils.h"
+#ifdef HAVE_ISULAD
+#include "lsm/lsm.h"
+#endif
 
 #if !HAVE_STRLCPY
 #include "strlcpy.h"
diff --git a/src/tests/aa.c b/src/tests/aa.c
index 417f3fc..f766640 100644
--- a/src/tests/aa.c
+++ b/src/tests/aa.c
@@ -40,7 +40,11 @@ static void try_to_remove(void)
 	}
 }
 
+#ifdef HAVE_ISULAD
+static int test_attach_write_file(void* payload, int msg_fd)
+#else
 static int test_attach_write_file(void* payload)
+#endif
 {
 	char *fnam = payload;
 	FILE *f;
diff --git a/src/tests/capabilities.c b/src/tests/capabilities.c
index 5704942..c54a051 100644
--- a/src/tests/capabilities.c
+++ b/src/tests/capabilities.c
@@ -41,7 +41,11 @@
 __u32 *cap_bset_bits = NULL;
 __u32 last_cap = 0;
 
+#ifdef HAVE_ISULAD
+static int capabilities_allow(void *payload, int msg_fd)
+#else
 static int capabilities_allow(void *payload)
+#endif
 {
 	for (__u32 cap = 0; cap <= last_cap; cap++) {
 		bool bret;
@@ -62,7 +66,11 @@ static int capabilities_allow(void *payload)
 	return EXIT_SUCCESS;
 }
 
+#ifdef HAVE_ISULAD
+static int capabilities_deny(void *payload, int msg_fd)
+#else
 static int capabilities_deny(void *payload)
+#endif
 {
 	for (__u32 cap = 0; cap <= last_cap; cap++) {
 		bool bret;
@@ -83,7 +91,11 @@ static int capabilities_deny(void *payload)
 	return EXIT_SUCCESS;
 }
 
+#ifdef HAVE_ISULAD
+static int run(int (*test)(void *, int), bool allow)
+#else
 static int run(int (*test)(void *), bool allow)
+#endif
 {
 	int fd_log = -EBADF, fret = -1;
 	lxc_attach_options_t attach_options = LXC_ATTACH_OPTIONS_DEFAULT;
diff --git a/src/tests/mount_injection.c b/src/tests/mount_injection.c
index f98370b..5e852eb 100644
--- a/src/tests/mount_injection.c
+++ b/src/tests/mount_injection.c
@@ -70,7 +70,11 @@ static int comp_field(char *line, const char *str, int nfields)
 	return ret;
 }
 
+#ifdef HAVE_ISULAD
+static int find_in_proc_mounts(void *data, int msg_fd)
+#else
 static int find_in_proc_mounts(void *data)
+#endif
 {
 	char buf[LXC_LINELEN];
 	FILE *f;
diff --git a/src/tests/proc_pid.c b/src/tests/proc_pid.c
index 9531ec2..56bbf52 100644
--- a/src/tests/proc_pid.c
+++ b/src/tests/proc_pid.c
@@ -15,7 +15,11 @@
 #define PROC_INIT_PATH "/proc/1/oom_score_adj"
 #define PROC_SELF_PATH "/proc/self/oom_score_adj"
 
+#ifdef HAVE_ISULAD
+static int check_oom_score_adj(void *payload, int msg_fd)
+#else
 static int check_oom_score_adj(void *payload)
+#endif
 {
 	__do_close int fd = -EBADF;
 	char buf[INTTYPE_TO_STRLEN(__s64)];
diff --git a/src/tests/rootfs_options.c b/src/tests/rootfs_options.c
index 55f86ab..73b88f9 100644
--- a/src/tests/rootfs_options.c
+++ b/src/tests/rootfs_options.c
@@ -60,7 +60,11 @@ static int has_mount_properties(const char *path, unsigned int flags)
 #endif
 }
 
+#ifdef HAVE_ISULAD
+static int rootfs_options(void *payload, int msg_fd)
+#else
 static int rootfs_options(void *payload)
+#endif
 {
 	int ret;
 
diff --git a/src/tests/sys_mixed.c b/src/tests/sys_mixed.c
index b51f28c..8a6ae53 100644
--- a/src/tests/sys_mixed.c
+++ b/src/tests/sys_mixed.c
@@ -56,7 +56,11 @@ static int is_read_only(const char *path)
 #endif
 }
 
+#ifdef HAVE_ISULAD
+static int sys_mixed(void *payload, int msg_fd)
+#else
 static int sys_mixed(void *payload)
+#endif
 {
 	int ret;
 
diff --git a/src/tests/sysctls.c b/src/tests/sysctls.c
index da4538f..6a715a3 100644
--- a/src/tests/sysctls.c
+++ b/src/tests/sysctls.c
@@ -16,7 +16,11 @@
 #define SYSCTL_CONFIG_KEY "lxc.sysctl.net.ipv4.ip_forward"
 #define SYSCTL_CONFIG_VALUE "1"
 
+#ifdef HAVE_ISULAD
+static int check_sysctls(void *payload, int msg_fd)
+#else
 static int check_sysctls(void *payload)
+#endif
 {
 	__do_close int fd = -EBADF;
 	char buf[INTTYPE_TO_STRLEN(__u64)];
-- 
2.25.1

