X-Git-Url: https://git.proxmox.com/?a=blobdiff_plain;f=lxcfs.c;h=76b3ea26f9ca2166f61e5c4de849b007b0240ca7;hb=8437cc6cb6b424cdb81db35915b7914ef934e736;hp=c53906c914fad2a0b7c179d2d67348f8e350195d;hpb=8dcde249026d5d5fe61133eb53642eb152798569;p=mirror_lxcfs.git

diff --git a/lxcfs.c b/lxcfs.c
index c53906c..76b3ea2 100644
--- a/lxcfs.c
+++ b/lxcfs.c
@@ -8,28 +8,30 @@
 
 #define FUSE_USE_VERSION 26
 
-#include <stdio.h>
+#include <alloca.h>
 #include <dirent.h>
+#include <dlfcn.h>
+#include <errno.h>
 #include <fcntl.h>
 #include <fuse.h>
-#include <unistd.h>
-#include <errno.h>
-#include <stdbool.h>
-#include <time.h>
-#include <string.h>
-#include <stdlib.h>
 #include <libgen.h>
-#include <sched.h>
 #include <pthread.h>
-#include <dlfcn.h>
+#include <sched.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include <unistd.h>
+#include <wait.h>
 #include <linux/sched.h>
-#include <sys/socket.h>
-#include <sys/mount.h>
 #include <sys/epoll.h>
-#include <wait.h>
+#include <sys/mount.h>
+#include <sys/socket.h>
+#include <linux/limits.h>
 
-#include "config.h" // for VERSION
 #include "bindings.h"
+#include "config.h" // for VERSION
 
 void *dlopen_handle;
 
@@ -42,7 +44,7 @@ static void lock_mutex(pthread_mutex_t *l)
 	int ret;
 
 	if ((ret = pthread_mutex_lock(l)) != 0) {
-		fprintf(stderr, "pthread_mutex_lock returned:%d %s\n", ret, strerror(ret));
+		lxcfs_error("returned:%d %s\n", ret, strerror(ret));
 		exit(1);
 	}
 }
@@ -52,7 +54,7 @@ static void unlock_mutex(pthread_mutex_t *l)
 	int ret;
 
 	if ((ret = pthread_mutex_unlock(l)) != 0) {
-		fprintf(stderr, "pthread_mutex_unlock returned:%d %s\n", ret, strerror(ret));
+		lxcfs_error("returned:%d %s\n", ret, strerror(ret));
 		exit(1);
 	}
 }
@@ -67,29 +69,87 @@ static void users_unlock(void)
 	unlock_mutex(&user_count_mutex);
 }
 
+static pthread_t loadavg_pid = 0;
+
+/* Returns zero on success */
+static int start_loadavg(void) {
+	char *error;
+	pthread_t (*load_daemon)(int);
+
+	dlerror();    /* Clear any existing error */
+
+	load_daemon = (pthread_t (*)(int)) dlsym(dlopen_handle, "load_daemon");
+	error = dlerror();
+	if (error != NULL) {
+		lxcfs_error("load_daemon fails:%s\n", error);
+		return -1;
+	}
+	loadavg_pid = load_daemon(1);
+	if (loadavg_pid == 0)
+		return -1;
+
+	return 0;
+}
+
+/* Returns zero on success */
+static int stop_loadavg(void) {
+	char *error;
+	int (*stop_load_daemon)(pthread_t);
+
+	stop_load_daemon = (int (*)(pthread_t)) dlsym(dlopen_handle, "stop_load_daemon");
+	error = dlerror();
+	if (error != NULL) {
+		lxcfs_error("stop_load_daemon error: %s\n", error);
+		return -1;
+	}
+
+	if (stop_load_daemon(loadavg_pid) != 0)
+		return -1;
+
+	return 0;
+}
+
 static volatile sig_atomic_t need_reload;
 
 /* do_reload - reload the dynamic library.  Done under
  * lock and when we know the user_count was 0 */
 static void do_reload(void)
 {
-	if (dlopen_handle)
+	char lxcfs_lib_path[PATH_MAX];
+
+	if (loadavg_pid > 0)
+		stop_loadavg();
+
+	if (dlopen_handle) {
+		lxcfs_debug("%s\n", "Closing liblxcfs.so handle.");
 		dlclose(dlopen_handle);
+	}
 
 	/* First try loading using ld.so */
 	dlopen_handle = dlopen("liblxcfs.so", RTLD_LAZY);
-	if (dlopen_handle)
+	if (dlopen_handle) {
+		lxcfs_debug("%s\n", "Successfully called dlopen() on liblxcfs.so.");
 		goto good;
+	}
 
-	dlopen_handle = dlopen("/usr/lib/lxcfs/liblxcfs.so", RTLD_LAZY);
+#ifdef LIBDIR
+	/* LIBDIR: autoconf will setup this MACRO. Default value is $PREFIX/lib */
+        snprintf(lxcfs_lib_path, PATH_MAX, "%s/lxcfs/liblxcfs.so", LIBDIR);
+#else
+        snprintf(lxcfs_lib_path, PATH_MAX, "/usr/local/lib/lxcfs/liblxcfs.so");
+#endif
+        dlopen_handle = dlopen(lxcfs_lib_path, RTLD_LAZY);
 	if (!dlopen_handle) {
-		fprintf(stderr, "Failed to open liblxcfs\n");
+		lxcfs_error("Failed to open liblxcfs.so: %s.\n", dlerror());
 		_exit(1);
 	}
 
 good:
+	if (loadavg_pid > 0)
+		start_loadavg();
+
 	if (need_reload)
-		fprintf(stderr, "lxcfs: reloaded\n");
+		lxcfs_error("%s\n", "lxcfs: reloaded");
 	need_reload = 0;
 }
 
@@ -123,7 +183,7 @@ static int do_cg_getattr(const char *path, struct stat *sb)
 	cg_getattr = (int (*)(const char *, struct stat *)) dlsym(dlopen_handle, "cg_getattr");
 	error = dlerror();
 	if (error != NULL) {
-		fprintf(stderr, "cg_getattr: %s\n", error);
+		lxcfs_error("%s\n", error);
 		return -1;
 	}
 
@@ -138,7 +198,7 @@ static int do_proc_getattr(const char *path, struct stat *sb)
 	proc_getattr = (int (*)(const char *, struct stat *)) dlsym(dlopen_handle, "proc_getattr");
 	error = dlerror();
 	if (error != NULL) {
-		fprintf(stderr, "proc_getattr: %s\n", error);
+		lxcfs_error("%s\n", error);
 		return -1;
 	}
 
@@ -156,7 +216,7 @@ static int do_cg_read(const char *path, char *buf, size_t size, off_t offset,
 	cg_read = (int (*)(const char *, char *, size_t, off_t, struct fuse_file_info *)) dlsym(dlopen_handle, "cg_read");
 	error = dlerror();
 	if (error != NULL) {
-		fprintf(stderr, "cg_read: %s\n", error);
+		lxcfs_error("%s\n", error);
 		return -1;
 	}
 
@@ -174,7 +234,7 @@ static int do_proc_read(const char *path, char *buf, size_t size, off_t offset,
 	proc_read = (int (*)(const char *, char *, size_t, off_t, struct fuse_file_info *)) dlsym(dlopen_handle, "proc_read");
 	error = dlerror();
 	if (error != NULL) {
-		fprintf(stderr, "proc_read: %s\n", error);
+		lxcfs_error("%s\n", error);
 		return -1;
 	}
 
@@ -191,7 +251,7 @@ static int do_cg_write(const char *path, const char *buf, size_t size, off_t off
 	cg_write = (int (*)(const char *, const char *, size_t, off_t, struct fuse_file_info *)) dlsym(dlopen_handle, "cg_write");
 	error = dlerror();
 	if (error != NULL) {
-		fprintf(stderr, "cg_write: %s\n", error);
+		lxcfs_error("%s\n", error);
 		return -1;
 	}
 
@@ -206,7 +266,7 @@ static int do_cg_mkdir(const char *path, mode_t mode)
 	cg_mkdir = (int (*)(const char *, mode_t)) dlsym(dlopen_handle, "cg_mkdir");
 	error = dlerror();
 	if (error != NULL) {
-		fprintf(stderr, "cg_mkdir: %s\n", error);
+		lxcfs_error("%s\n", error);
 		return -1;
 	}
 
@@ -221,7 +281,7 @@ static int do_cg_chown(const char *path, uid_t uid, gid_t gid)
 	cg_chown = (int (*)(const char *, uid_t, gid_t)) dlsym(dlopen_handle, "cg_chown");
 	error = dlerror();
 	if (error != NULL) {
-		fprintf(stderr, "cg_chown: %s\n", error);
+		lxcfs_error("%s\n", error);
 		return -1;
 	}
 
@@ -236,7 +296,7 @@ static int do_cg_rmdir(const char *path)
 	cg_rmdir = (int (*)(const char *path)) dlsym(dlopen_handle, "cg_rmdir");
 	error = dlerror();
 	if (error != NULL) {
-		fprintf(stderr, "cg_rmdir: %s\n", error);
+		lxcfs_error("%s\n", error);
 		return -1;
 	}
 
@@ -251,7 +311,7 @@ static int do_cg_chmod(const char *path, mode_t mode)
 	cg_chmod = (int (*)(const char *, mode_t)) dlsym(dlopen_handle, "cg_chmod");
 	error = dlerror();
 	if (error != NULL) {
-		fprintf(stderr, "cg_chmod: %s\n", error);
+		lxcfs_error("%s\n", error);
 		return -1;
 	}
 
@@ -269,7 +329,7 @@ static int do_cg_readdir(const char *path, void *buf, fuse_fill_dir_t filler, of
 	cg_readdir = (int (*)(const char *, void *, fuse_fill_dir_t, off_t, struct fuse_file_info *)) dlsym(dlopen_handle, "cg_readdir");
 	error = dlerror();
 	if (error != NULL) {
-		fprintf(stderr, "cg_readdir: %s\n", error);
+		lxcfs_error("%s\n", error);
 		return -1;
 	}
 
@@ -287,7 +347,7 @@ static int do_proc_readdir(const char *path, void *buf, fuse_fill_dir_t filler,
 	proc_readdir = (int (*)(const char *, void *, fuse_fill_dir_t, off_t, struct fuse_file_info *)) dlsym(dlopen_handle, "proc_readdir");
 	error = dlerror();
 	if (error != NULL) {
-		fprintf(stderr, "proc_readdir: %s\n", error);
+		lxcfs_error("%s\n", error);
 		return -1;
 	}
 
@@ -302,13 +362,28 @@ static int do_cg_open(const char *path, struct fuse_file_info *fi)
 	cg_open = (int (*)(const char *, struct fuse_file_info *)) dlsym(dlopen_handle, "cg_open");
 	error = dlerror();
 	if (error != NULL) {
-		fprintf(stderr, "cg_open: %s\n", error);
+		lxcfs_error("%s\n", error);
 		return -1;
 	}
 
 	return cg_open(path, fi);
 }
 
+static int do_cg_access(const char *path, int mode)
+{
+	int (*cg_access)(const char *path, int mode);
+	char *error;
+	dlerror();    /* Clear any existing error */
+	cg_access = (int (*)(const char *, int mode)) dlsym(dlopen_handle, "cg_access");
+	error = dlerror();
+	if (error != NULL) {
+		lxcfs_error("%s\n", error);
+		return -1;
+	}
+
+	return cg_access(path, mode);
+}
+
 static int do_proc_open(const char *path, struct fuse_file_info *fi)
 {
 	int (*proc_open)(const char *path, struct fuse_file_info *fi);
@@ -317,13 +392,28 @@ static int do_proc_open(const char *path, struct fuse_file_info *fi)
 	proc_open = (int (*)(const char *path, struct fuse_file_info *fi)) dlsym(dlopen_handle, "proc_open");
 	error = dlerror();
 	if (error != NULL) {
-		fprintf(stderr, "proc_open: %s\n", error);
+		lxcfs_error("%s\n", error);
 		return -1;
 	}
 
 	return proc_open(path, fi);
 }
 
+static int do_proc_access(const char *path, int mode)
+{
+	int (*proc_access)(const char *path, int mode);
+	char *error;
+	dlerror();    /* Clear any existing error */
+	proc_access = (int (*)(const char *, int mode)) dlsym(dlopen_handle, "proc_access");
+	error = dlerror();
+	if (error != NULL) {
+		lxcfs_error("%s\n", error);
+		return -1;
+	}
+
+	return proc_access(path, mode);
+}
+
 static int do_cg_release(const char *path, struct fuse_file_info *fi)
 {
 	int (*cg_release)(const char *path, struct fuse_file_info *fi);
@@ -332,7 +422,7 @@ static int do_cg_release(const char *path, struct fuse_file_info *fi)
 	cg_release = (int (*)(const char *path, struct fuse_file_info *)) dlsym(dlopen_handle, "cg_release");
 	error = dlerror();
 	if (error != NULL) {
-		fprintf(stderr, "cg_release: %s\n", error);
+		lxcfs_error("%s\n", error);
 		return -1;
 	}
 
@@ -347,7 +437,7 @@ static int do_proc_release(const char *path, struct fuse_file_info *fi)
 	proc_release = (int (*)(const char *path, struct fuse_file_info *)) dlsym(dlopen_handle, "proc_release");
 	error = dlerror();
 	if (error != NULL) {
-		fprintf(stderr, "proc_release: %s\n", error);
+		lxcfs_error("%s\n", error);
 		return -1;
 	}
 
@@ -362,7 +452,7 @@ static int do_cg_opendir(const char *path, struct fuse_file_info *fi)
 	cg_opendir = (int (*)(const char *path, struct fuse_file_info *fi)) dlsym(dlopen_handle, "cg_opendir");
 	error = dlerror();
 	if (error != NULL) {
-		fprintf(stderr, "cg_opendir: %s\n", error);
+		lxcfs_error("%s\n", error);
 		return -1;
 	}
 
@@ -377,7 +467,7 @@ static int do_cg_releasedir(const char *path, struct fuse_file_info *fi)
 	cg_releasedir = (int (*)(const char *path, struct fuse_file_info *)) dlsym(dlopen_handle, "cg_releasedir");
 	error = dlerror();
 	if (error != NULL) {
-		fprintf(stderr, "cg_releasedir: %s\n", error);
+		lxcfs_error("%s\n", error);
 		return -1;
 	}
 
@@ -393,11 +483,19 @@ static int do_cg_releasedir(const char *path, struct fuse_file_info *fi)
 static int lxcfs_getattr(const char *path, struct stat *sb)
 {
 	int ret;
+	struct timespec now;
+
 	if (strcmp(path, "/") == 0) {
+		if (clock_gettime(CLOCK_REALTIME, &now) < 0)
+			return -EINVAL;
+		sb->st_uid = sb->st_gid = 0;
+		sb->st_atim = sb->st_mtim = sb->st_ctim = now;
+		sb->st_size = 0;
 		sb->st_mode = S_IFDIR | 00755;
 		sb->st_nlink = 2;
 		return 0;
 	}
+
 	if (strncmp(path, "/cgroup", 7) == 0) {
 		up_users();
 		ret = do_cg_getattr(path, sb);
@@ -410,7 +508,7 @@ static int lxcfs_getattr(const char *path, struct stat *sb)
 		down_users();
 		return ret;
 	}
-	return -EINVAL;
+	return -ENOENT;
 }
 
 static int lxcfs_opendir(const char *path, struct fuse_file_info *fi)
@@ -435,9 +533,11 @@ static int lxcfs_readdir(const char *path, void *buf, fuse_fill_dir_t filler, of
 {
 	int ret;
 	if (strcmp(path, "/") == 0) {
-		if (filler(buf, "proc", NULL, 0) != 0 ||
-				filler(buf, "cgroup", NULL, 0) != 0)
-			return -EINVAL;
+		if (filler(buf, ".", NULL, 0) != 0 ||
+		    filler(buf, "..", NULL, 0) != 0 ||
+		    filler(buf, "proc", NULL, 0) != 0 ||
+		    filler(buf, "cgroup", NULL, 0) != 0)
+			return -ENOMEM;
 		return 0;
 	}
 	if (strncmp(path, "/cgroup", 7) == 0) {
@@ -452,7 +552,30 @@ static int lxcfs_readdir(const char *path, void *buf, fuse_fill_dir_t filler, of
 		down_users();
 		return ret;
 	}
-	return -EINVAL;
+	return -ENOENT;
+}
+
+static int lxcfs_access(const char *path, int mode)
+{
+	int ret;
+
+	if (strcmp(path, "/") == 0 && (mode & W_OK) == 0)
+		return 0;
+
+	if (strncmp(path, "/cgroup", 7) == 0) {
+		up_users();
+		ret = do_cg_access(path, mode);
+		down_users();
+		return ret;
+	}
+	if (strncmp(path, "/proc", 5) == 0) {
+		up_users();
+		ret = do_proc_access(path, mode);
+		down_users();
+		return ret;
+	}
+
+	return -EACCES;
 }
 
 static int lxcfs_releasedir(const char *path, struct fuse_file_info *fi)
@@ -487,7 +610,7 @@ static int lxcfs_open(const char *path, struct fuse_file_info *fi)
 		return ret;
 	}
 
-	return -EINVAL;
+	return -EACCES;
 }
 
 static int lxcfs_read(const char *path, char *buf, size_t size, off_t offset,
@@ -563,7 +686,7 @@ int lxcfs_mkdir(const char *path, mode_t mode)
 		return ret;
 	}
 
-	return -EINVAL;
+	return -EPERM;
 }
 
 int lxcfs_chown(const char *path, uid_t uid, gid_t gid)
@@ -576,7 +699,10 @@ int lxcfs_chown(const char *path, uid_t uid, gid_t gid)
 		return ret;
 	}
 
-	return -EINVAL;
+	if (strncmp(path, "/proc", 5) == 0)
+		return -EPERM;
+
+	return -ENOENT;
 }
 
 /*
@@ -588,7 +714,7 @@ int lxcfs_truncate(const char *path, off_t newsize)
 {
 	if (strncmp(path, "/cgroup", 7) == 0)
 		return 0;
-	return -EINVAL;
+	return -EPERM;
 }
 
 int lxcfs_rmdir(const char *path)
@@ -600,7 +726,7 @@ int lxcfs_rmdir(const char *path)
 		down_users();
 		return ret;
 	}
-	return -EINVAL;
+	return -EPERM;
 }
 
 int lxcfs_chmod(const char *path, mode_t mode)
@@ -612,7 +738,11 @@ int lxcfs_chmod(const char *path, mode_t mode)
 		down_users();
 		return ret;
 	}
-	return -EINVAL;
+
+	if (strncmp(path, "/proc", 5) == 0)
+		return -EPERM;
+
+	return -ENOENT;
 }
 
 const struct fuse_operations lxcfs_ops = {
@@ -652,19 +782,21 @@ const struct fuse_operations lxcfs_ops = {
 	.fsyncdir = NULL,
 	.init = NULL,
 	.destroy = NULL,
-	.access = NULL,
+	.access = lxcfs_access,
 	.create = NULL,
 	.ftruncate = NULL,
 	.fgetattr = NULL,
 };
 
-static void usage(const char *me)
+static void usage()
 {
 	fprintf(stderr, "Usage:\n");
 	fprintf(stderr, "\n");
-	fprintf(stderr, "%s [-p pidfile] mountpoint\n", me);
+	fprintf(stderr, "lxcfs [-f|-d] -l [-p pidfile] mountpoint\n");
+	fprintf(stderr, "  -f running foreground by default; -d enable debug output \n");
+	fprintf(stderr, "  -l use loadavg \n");
 	fprintf(stderr, "  Default pidfile is %s/lxcfs.pid\n", RUNTIME_PATH);
-	fprintf(stderr, "%s -h\n", me);
+	fprintf(stderr, "lxcfs -h\n");
 	exit(1);
 }
 
@@ -678,7 +810,7 @@ static bool is_help(char *w)
 	return false;
 }
 
-void swallow_arg(int *argcp, char *argv[], char *which)
+bool swallow_arg(int *argcp, char *argv[], char *which)
 {
 	int i;
 
@@ -689,8 +821,9 @@ void swallow_arg(int *argcp, char *argv[], char *which)
 			argv[i] = argv[i+1];
 		}
 		(*argcp)--;
-		return;
+		return true;
 	}
+	return false;
 }
 
 bool swallow_option(int *argcp, char *argv[], char *opt, char **v)
@@ -714,127 +847,6 @@ bool swallow_option(int *argcp, char *argv[], char *opt, char **v)
 	return false;
 }
 
-static bool mkdir_p(const char *dir, mode_t mode)
-{
-	const char *tmp = dir;
-	const char *orig = dir;
-	char *makeme;
-
-	do {
-		dir = tmp + strspn(tmp, "/");
-		tmp = dir + strcspn(dir, "/");
-		makeme = strndup(orig, dir - orig);
-		if (!makeme)
-			return false;
-		if (mkdir(makeme, mode) && errno != EEXIST) {
-			fprintf(stderr, "failed to create directory '%s': %s",
-				makeme, strerror(errno));
-			free(makeme);
-			return false;
-		}
-		free(makeme);
-	} while(tmp != dir);
-
-	return true;
-}
-
-static bool umount_if_mounted(void)
-{
-	if (umount2(basedir, MNT_DETACH) < 0 && errno != EINVAL) {
-		fprintf(stderr, "failed to umount %s: %s\n", basedir,
-			strerror(errno));
-		return false;
-	}
-	return true;
-}
-
-static bool setup_cgfs_dir(void)
-{
-	if (!mkdir_p(basedir, 0700)) {
-		fprintf(stderr, "Failed to create lxcfs cgdir\n");
-		return false;
-	}
-	if (!umount_if_mounted()) {
-		fprintf(stderr, "Failed to clean up old lxcfs cgdir\n");
-		return false;
-	}
-	if (mount("tmpfs", basedir, "tmpfs", 0, "size=100000,mode=700") < 0) {
-		fprintf(stderr, "Failed to mount tmpfs for private controllers\n");
-		return false;
-	}
-	return true;
-}
-
-static bool do_mount_cgroup(char *controller)
-{
-	char *target;
-	size_t len;
-	int ret;
-
-	len = strlen(basedir) + strlen(controller) + 2;
-	target = alloca(len);
-	ret = snprintf(target, len, "%s/%s", basedir, controller);
-	if (ret < 0 || ret >= len)
-		return false;
-	if (mkdir(target, 0755) < 0 && errno != EEXIST)
-		return false;
-	if (mount(controller, target, "cgroup", 0, controller) < 0) {
-		fprintf(stderr, "Failed mounting cgroup %s\n", controller);
-		return false;
-	}
-	return true;
-}
-
-static bool do_mount_cgroups(void)
-{
-	bool ret;
-	FILE *f;
-	char *line = NULL;
-	size_t len = 0;
-
-	if ((f = fopen("/proc/self/cgroup", "r")) == NULL) {
-		fprintf(stderr, "Error opening /proc/self/cgroup: %s\n", strerror(errno));
-		return false;
-	}
-
-	while (getline(&line, &len, f) != -1) {
-		char *p, *p2;
-
-		p = strchr(line, ':');
-		if (!p)
-			goto out;
-		*(p++) = '\0';
-
-		p2 = strrchr(p, ':');
-		if (!p2)
-			goto out;
-		*p2 = '\0';
-
-		if (!do_mount_cgroup(p))
-			goto out;
-	}
-	ret = true;
-
-out:
-	free(line);
-	fclose(f);
-	return ret;
-}
-
-static bool cgfs_setup_controllers(void)
-{
-	if (!setup_cgfs_dir()) {
-		return false;
-	}
-
-	if (!do_mount_cgroups()) {
-		fprintf(stderr, "Failed to set up cgroup mounts\n");
-		return false;
-	}
-
-	return true;
-}
-
 static int set_pidfile(char *pidfile)
 {
 	int fd;
@@ -848,7 +860,7 @@ static int set_pidfile(char *pidfile)
 
 	fd = open(pidfile, O_RDWR | O_CREAT, S_IRUSR | S_IWUSR);
 	if (fd == -1) {
-		fprintf(stderr, "Could not open pidfile %s: %m", pidfile);
+		fprintf(stderr, "Could not open pidfile %s: %m\n", pidfile);
 		return -1;
 	}
 
@@ -879,12 +891,15 @@ static int set_pidfile(char *pidfile)
 
 int main(int argc, char *argv[])
 {
-	int ret = -1, pidfd;
-	char *pidfile = NULL, *v = NULL;
+	int ret = EXIT_FAILURE;
+	int pidfd = -1;
+	char *pidfile = NULL, *saveptr = NULL, *token = NULL, *v = NULL;
 	size_t pidfile_len;
+	bool debug = false, nonempty = false;
+	bool load_use = false;
 	/*
 	 * what we pass to fuse_main is:
-	 * argv[0] -s -f -o allow_other,directio argv[1] NULL
+	 * argv[0] -s [-f|-d] -o allow_other,directio argv[1] NULL
 	 */
 	int nargs = 5, cnt = 0;
 	char *newargv[6];
@@ -892,10 +907,22 @@ int main(int argc, char *argv[])
 	/* accomodate older init scripts */
 	swallow_arg(&argc, argv, "-s");
 	swallow_arg(&argc, argv, "-f");
+	debug = swallow_arg(&argc, argv, "-d");
+	if (swallow_arg(&argc, argv, "-l")) {
+		load_use = true;
+	}
 	if (swallow_option(&argc, argv, "-o", &v)) {
-		if (strcmp(v, "allow_other") != 0) {
-			fprintf(stderr, "Warning: unexpected fuse option %s\n", v);
-			exit(1);
+		/* Parse multiple values */
+		for (; (token = strtok_r(v, ",", &saveptr)); v = NULL) {
+			if (strcmp(token, "allow_other") == 0) {
+				/* Noop. this is the default. Always enabled. */
+			} else if (strcmp(token, "nonempty") == 0) {
+				nonempty = true;
+			} else {
+				free(v);
+				fprintf(stderr, "Warning: unexpected fuse option %s\n", v);
+				exit(EXIT_FAILURE);
+			}
 		}
 		free(v);
 		v = NULL;
@@ -905,27 +932,30 @@ int main(int argc, char *argv[])
 
 	if (argc == 2  && strcmp(argv[1], "--version") == 0) {
 		fprintf(stderr, "%s\n", VERSION);
-		exit(0);
+		exit(EXIT_SUCCESS);
 	}
 	if (argc != 2 || is_help(argv[1]))
-		usage(argv[0]);
+		usage();
 
 	do_reload();
 	if (signal(SIGUSR1, reload_handler) == SIG_ERR) {
 		fprintf(stderr, "Error setting USR1 signal handler: %m\n");
-		exit(1);
+		goto out;
 	}
 
 	newargv[cnt++] = argv[0];
-	newargv[cnt++] = "-f";
+	if (debug)
+		newargv[cnt++] = "-d";
+	else
+		newargv[cnt++] = "-f";
 	newargv[cnt++] = "-o";
-	newargv[cnt++] = "allow_other,direct_io,entry_timeout=0.5,attr_timeout=0.5";
+	if (nonempty)
+		newargv[cnt++] = "allow_other,direct_io,entry_timeout=0.5,attr_timeout=0.5,nonempty";
+	else
+		newargv[cnt++] = "allow_other,direct_io,entry_timeout=0.5,attr_timeout=0.5";
 	newargv[cnt++] = argv[1];
 	newargv[cnt++] = NULL;
 
-	if (!cgfs_setup_controllers())
-		goto out;
-
 	if (!pidfile) {
 		pidfile_len = strlen(RUNTIME_PATH) + strlen("/lxcfs.pid") + 1;
 		pidfile = alloca(pidfile_len);
@@ -934,12 +964,20 @@ int main(int argc, char *argv[])
 	if ((pidfd = set_pidfile(pidfile)) < 0)
 		goto out;
 
-	ret = fuse_main(nargs, newargv, &lxcfs_ops, NULL);
+	if (load_use && start_loadavg() != 0)
+		goto out;
 
-	dlclose(dlopen_handle);
-	unlink(pidfile);
-	close(pidfd);
+	if (!fuse_main(nargs, newargv, &lxcfs_ops, NULL))
+		ret = EXIT_SUCCESS;
+	if (load_use)
+		stop_loadavg();
 
 out:
-	return ret;
+	if (dlopen_handle)
+		dlclose(dlopen_handle);
+	if (pidfile)
+		unlink(pidfile);
+	if (pidfd > 0)
+		close(pidfd);
+	exit(ret);
 }