Merge branch 'parser' of git://github.com/idryomov/btrfs-progs

12 files changed, 2231 insertions, 1765 deletions

diff --git a/Makefile b/Makefile
index 834be47..deafda6 100644
--- a/Makefile
+++ b/Makefile
@@ -5,6 +5,8 @@ objects = ctree.o disk-io.o radix-tree.o extent-tree.o print-tree.o \
 	  root-tree.o dir-item.o file-item.o inode-item.o \
 	  inode-map.o crc32c.o rbtree.o extent-cache.o extent_io.o \
 	  volumes.o utils.o btrfs-list.o btrfslabel.o
+cmds_objects = cmds-subvolume.o cmds-filesystem.o cmds-device.o cmds-scrub.o \
+	       cmds-inspect.o
 
 CHECKFLAGS= -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ -Wbitwise \
 	    -Wuninitialized -Wshadow -Wundef
@@ -36,8 +38,8 @@ all: version $(progs) manpages
 version:
 	bash version.sh
 
-btrfs: $(objects) btrfs.o btrfs_cmds.o scrub.o
-	$(CC) $(CFLAGS) -o btrfs btrfs.o btrfs_cmds.o scrub.o \
+btrfs: $(objects) btrfs.o help.o common.o $(cmds_objects)
+	$(CC) $(CFLAGS) -o btrfs btrfs.o help.o common.o $(cmds_objects) \
 		$(objects) $(LDFLAGS) $(LIBS) -lpthread
 
 calc-size: $(objects) calc-size.o
diff --git a/btrfs.c b/btrfs.c
index 1def354..599a3e7 100644
--- a/btrfs.c
+++ b/btrfs.c
@@ -19,444 +19,255 @@
 #include <stdlib.h>
 #include <string.h>
 
-#include "kerncompat.h"
-#include "btrfs_cmds.h"
+#include "commands.h"
 #include "version.h"
 
-#define BASIC_HELP 0
-#define ADVANCED_HELP 1
-
-typedef int (*CommandFunction)(int argc, char **argv);
-
-struct Command {
-	CommandFunction	func;	/* function which implements the command */
-	int	nargs;		/* if == 999, any number of arguments
-				   if >= 0, number of arguments,
-				   if < 0, _minimum_ number of arguments */
-	char	*verb;		/* verb */
-	char	*help;		/* help lines; from the 2nd line onward they 
-                                   are automatically indented */
-        char    *adv_help;      /* advanced help message; from the 2nd line 
-                                   onward they are automatically indented */
-
-	/* the following fields are run-time filled by the program */
-	char	**cmds;		/* array of subcommands */
-	int	ncmds;		/* number of subcommand */
-};
+static const char btrfs_cmd_group_usage[] =
+	"btrfs [--help] [--version] <group> [<group>...] <command> [<args>]";
 
-static struct Command commands[] = {
+static const char btrfs_cmd_group_info[] =
+	"Use --help as an argument for information on a specific group or command.";
 
-	/*
-		avoid short commands different for the case only
-	*/
-	{ do_clone, -2,
-	  "subvolume snapshot", "[-r] <source> [<dest>/]<name>\n"
-		"Create a writable/readonly snapshot of the subvolume <source> with\n"
-		"the name <name> in the <dest> directory.",
-	  NULL
-	},
-	{ do_delete_subvolume, 1,
-	  "subvolume delete", "<subvolume>\n"
-		"Delete the subvolume <subvolume>.",
-	  NULL
-	},
-	{ do_create_subvol, 1,
-	  "subvolume create", "[<dest>/]<name>\n"
-		"Create a subvolume in <dest> (or the current directory if\n"
-		"not passed).",
-	  NULL
-	},
-	{ do_subvol_list, -1, "subvolume list", "[-p] <path>\n"
-		"List the snapshot/subvolume of a filesystem.",
-		"[-p] <path>\n"
-		"List the snapshot/subvolume of a filesystem.\n"
-		"-p	   print parent ID"
-	},
-	{ do_set_default_subvol, 2,
-	  "subvolume set-default", "<id> <path>\n"
-		"Set the subvolume of the filesystem <path> which will be mounted\n"
-		"as default.",
-	  NULL
-	},
-	{ do_find_newer, 2, "subvolume find-new", "<path> <last_gen>\n"
-		"List the recently modified files in a filesystem.",
-	  NULL
-	},
-	{ do_defrag, -1,
-	  "filesystem defragment", "[-vf] [-c[zlib,lzo]] [-s start] [-l len] [-t size] <file>|<dir> [<file>|<dir>...]\n"
-		"Defragment a file or a directory.",
-	  	"[-vcf] [-s start] [-l len] [-t size] <file>|<dir> [<file>|<dir>...]\n"
-		"Defragment file data or directory metadata.\n"
-		"-v         be verbose\n"
-		"-c         compress the file while defragmenting\n"
-		"-f         flush data to disk immediately after defragmenting\n"
-		"-s start   defragment only from byte onward\n"
-		"-l len     defragment only up to len bytes\n"
-		"-t size    minimal size of file to be considered for defragmenting\n"
-	},
-	{ do_get_default_subvol, 1, "subvolume get-default", "<path>\n"
-		"Get the default subvolume of a filesystem."
-	},
-	{ do_fssync, 1,
-	  "filesystem sync", "<path>\n"
-		"Force a sync on the filesystem <path>.",
-	  NULL
-	},
-	{ do_resize, 2,
-	  "filesystem resize", "[+/-]<newsize>[gkm]|max <filesystem>\n"
-		"Resize the file system. If 'max' is passed, the filesystem\n"
-		"will occupe all available space on the device.",
-	  NULL
-	},
-	{ do_show_filesystem, 999,
-	  "filesystem show", "[--all-devices][<uuid>|<label>]\n"
-		"Show the info of a btrfs filesystem. If no argument\n"
-		"is passed, info of all the btrfs filesystem are shown.",
-	  NULL
-	},
-	{ do_df_filesystem, 1,
-	  "filesystem df", "<path>\n"
-		"Show space usage information for a mount point.",
-	  NULL
-	},
-	{ do_balance, 1,
-	  "filesystem balance", "<path>\n"
-		"Balance the chunks across the device.",
-	  NULL
-	},
-	{ do_change_label, -1,
-	  "filesystem label", "<device> [<newlabel>]\n"
-	  "With one argument, get the label of filesystem on <device>.\n"
-	  "If <newlabel> is passed, set the filesystem label to <newlabel>.\n"
-	  "The filesystem must be unmounted.\n"
-	},
-	{ do_scrub_start, -1,
-	  "scrub start", "[-Bdqr] <path>|<device>\n"
-		"Start a new scrub.",
-		"\n-B  do not background\n"
-		"-d  stats per device (-B only)\n"
-		"-q  quiet\n"
-		"-r  read only mode\n"
-	},
-	{ do_scrub_cancel, 1,
-	  "scrub cancel", "<path>|<device>\n"
-		"Cancel a running scrub.",
-	  NULL
-	},
-	{ do_scrub_resume, -1,
-	  "scrub resume", "[-Bdqr] <path>|<device>\n"
-		"Resume previously canceled or interrupted scrub.",
-	  NULL
-	},
-	{ do_scrub_status, -1,
-	  "scrub status", "[-d] <path>|<device>\n"
-		"Show status of running or finished scrub.",
-	  NULL
-	},
-	{ do_scan, 999, 
-	  "device scan", "[<device>...]\n"
-		"Scan all device for or the passed device for a btrfs\n"
-		"filesystem.",
-	  NULL
-	},
-	{ do_add_volume, -2,
-	  "device add", "<device> [<device>...] <path>\n"
-		"Add a device to a filesystem.",
-	  NULL
-	},
-	{ do_remove_volume, -2,
-	  "device delete", "<device> [<device>...] <path>\n"
-		"Remove a device from a filesystem.",
-	  NULL
-	},
-	{ do_ino_to_path, -2,
-	  "inspect-internal inode-resolve", "[-v] <inode> <path>\n"
-		"get file system paths for the given inode.",
-	  NULL
-	},
-	{ do_logical_to_ino, -2,
-	  "inspect-internal logical-resolve", "[-v] [-P] <logical> <path>\n"
-		"get file system paths for the given logical address.",
-	  NULL
-	},
-	{ 0, 0, 0, 0 }
-};
+char argv0_buf[ARGV0_BUF_SIZE] = "btrfs";
 
-static char *get_prgname(char *programname)
+static inline const char *skip_prefix(const char *str, const char *prefix)
 {
-	char	*np;
-	np = strrchr(programname,'/');
-	if(!np)
-		np = programname;
-	else
-		np++;
-
-	return np;
+	size_t len = strlen(prefix);
+	return strncmp(str, prefix, len) ? NULL : str + len;
 }
 
-static void print_help(char *programname, struct Command *cmd, int helptype)
+int prefixcmp(const char *str, const char *prefix)
 {
-	char	*pc;
-
-	printf("\t%s %s ", programname, cmd->verb );
+	for (; ; str++, prefix++)
+		if (!*prefix)
+			return 0;
+		else if (*str != *prefix)
+			return (unsigned char)*prefix - (unsigned char)*str;
+}
 
-	if (helptype == ADVANCED_HELP && cmd->adv_help)
-		for(pc = cmd->adv_help; *pc; pc++){
-			putchar(*pc);
-			if(*pc == '\n')
-				printf("\t\t");
-		}
-	else
-		for(pc = cmd->help; *pc; pc++){
-			putchar(*pc);
-			if(*pc == '\n')
-				printf("\t\t");
+static int parse_one_token(const char *arg, const struct cmd_group *grp,
+			   const struct cmd_struct **cmd_ret)
+{
+	const struct cmd_struct *cmd = grp->commands;
+	const struct cmd_struct *abbrev_cmd = NULL, *ambiguous_cmd = NULL;
+
+	for (; cmd->token; cmd++) {
+		const char *rest;
+
+		rest = skip_prefix(arg, cmd->token);
+		if (!rest) {
+			if (!prefixcmp(cmd->token, arg)) {
+				if (abbrev_cmd) {
+					/*
+					 * If this is abbreviated, it is
+					 * ambiguous. So when there is no
+					 * exact match later, we need to
+					 * error out.
+					 */
+					ambiguous_cmd = abbrev_cmd;
+				}
+				abbrev_cmd = cmd;
+			}
+			continue;
 		}
+		if (*rest)
+			continue;
 
-	putchar('\n');
-}
+		*cmd_ret = cmd;
+		return 0;
+	}
 
-static void help(char *np)
-{
-	struct Command *cp;
+	if (ambiguous_cmd)
+		return -2;
 
-	printf("Usage:\n");
-	for( cp = commands; cp->verb; cp++ )
-		print_help(np, cp, BASIC_HELP);
+	if (abbrev_cmd) {
+		*cmd_ret = abbrev_cmd;
+		return 0;
+	}
 
-	printf("\n\t%s help|--help|-h\n\t\tShow the help.\n",np);
-	printf("\n\t%s <cmd> --help\n\t\tShow detailed help for a command or\n\t\t"
-	       "subset of commands.\n",np);
-	printf("\n%s\n", BTRFS_BUILD_VERSION);
+	return -1;
 }
 
-static int split_command(char *cmd, char ***commands)
+static const struct cmd_struct *
+parse_command_token(const char *arg, const struct cmd_group *grp)
 {
-	int	c, l;
-	char	*p, *s;
+	const struct cmd_struct *cmd;
 
-	for( *commands = 0, l = c = 0, p = s = cmd ; ; p++, l++ ){
-		if ( *p && *p != ' ' )
-			continue;
-
-		/* c + 2 so that we have room for the null */
-		(*commands) = realloc( (*commands), sizeof(char *)*(c + 2));
-		(*commands)[c] = strndup(s, l);
-		c++;
-		l = 0;
-		s = p+1;
-		if( !*p ) break;
+	switch(parse_one_token(arg, grp, &cmd)) {
+	case -1:
+		help_unknown_token(arg, grp);
+	case -2:
+		help_ambiguous_token(arg, grp);
 	}
 
-	(*commands)[c] = 0;
-	return c;
+	return cmd;
 }
 
-/*
-	This function checks if the passed command is ambiguous
-*/
-static int check_ambiguity(struct Command *cmd, char **argv){
-	int		i;
-	struct Command	*cp;
-	/* check for ambiguity */
-	for( i = 0 ; i < cmd->ncmds ; i++ ){
-		int match;
-		for( match = 0, cp = commands; cp->verb; cp++ ){
-			int	j, skip;
-			char	*s1, *s2;
-
-			if( cp->ncmds < i )
-				continue;
-
-			for( skip = 0, j = 0 ; j < i ; j++ )
-				if( strcmp(cmd->cmds[j], cp->cmds[j])){
-					skip=1;
-					break;
-				}
-			if(skip)
-				continue;
-
-			if( !strcmp(cmd->cmds[i], cp->cmds[i]))
-				continue;
-			for(s2 = cp->cmds[i], s1 = argv[i+1];
-				*s1 == *s2 && *s1; s1++, s2++ ) ;
-			if( !*s1 )
-				match++;
-		}
-		if(match){
-			int j;
-			fprintf(stderr, "ERROR: in command '");
-			for( j = 0 ; j <= i ; j++ )
-				fprintf(stderr, "%s%s",j?" ":"", argv[j+1]);
-			fprintf(stderr, "', '%s' is ambiguous\n",argv[j]);
-			return -2;
+void handle_help_options_next_level(const struct cmd_struct *cmd,
+				    int argc, char **argv)
+{
+	if (argc < 2)
+		return;
+
+	if (!strcmp(argv[1], "--help")) {
+		if (cmd->next) {
+			argc--;
+			argv++;
+			help_command_group(cmd->next, argc, argv);
+		} else {
+			usage_command(cmd, 1, 0);
 		}
+
+		exit(0);
 	}
-	return 0;
 }
 
-/*
- * This function, compacts the program name and the command in the first
- * element of the '*av' array
- */
-static int prepare_args(int *ac, char ***av, char *prgname, struct Command *cmd ){
-
-	char	**ret;
-	int	i;
-	char	*newname;
-
-	ret = (char **)malloc(sizeof(char*)*(*ac+1));
-	newname = (char*)malloc(strlen(prgname)+strlen(cmd->verb)+2);
-	if( !ret || !newname ){
-		free(ret);
-		free(newname);
-		return -1;
-	}
+static void fixup_argv0(char **argv, const char *token)
+{
+	int len = strlen(argv0_buf);
 
-	ret[0] = newname;
-	for(i=0; i < *ac ; i++ )
-		ret[i+1] = (*av)[i];
+	snprintf(argv0_buf + len, sizeof(argv0_buf) - len, " %s", token);
+	argv[0] = argv0_buf;
+}
 
-	strcpy(newname, prgname);
-	strcat(newname, " ");
-	strcat(newname, cmd->verb);
+int handle_command_group(const struct cmd_group *grp, int argc,
+			 char **argv)
 
-	(*ac)++;
-	*av = ret;
+{
+	const struct cmd_struct *cmd;
 
-	return 0;
+	argc--;
+	argv++;
+	if (argc < 1) {
+		usage_command_group(grp, 0, 0);
+		exit(1);
+	}
 
+	cmd = parse_command_token(argv[0], grp);
+
+	handle_help_options_next_level(cmd, argc, argv);
+
+	fixup_argv0(argv, cmd->token);
+	return cmd->fn(argc, argv);
 }
 
+int check_argc_exact(int nargs, int expected)
+{
+	if (nargs < expected)
+		fprintf(stderr, "%s: too few arguments\n", argv0_buf);
+	if (nargs > expected)
+		fprintf(stderr, "%s: too many arguments\n", argv0_buf);
 
+	return nargs != expected;
+}
 
-/*
-	This function performs the following jobs:
-	- show the help if '--help' or 'help' or '-h' are passed
-	- verify that a command is not ambiguous, otherwise show which
-	  part of the command is ambiguous
-	- if after a (even partial) command there is '--help' show detailed help
-	  for all the matching commands
-	- if the command doesn't match show an error
-	- finally, if a command matches, they return which command matched and
-	  the arguments
-
-	The function return 0 in case of help is requested; <0 in case
-	of uncorrect command; >0 in case of matching commands
-	argc, argv are the arg-counter and arg-vector (input)
-	*nargs_ is the number of the arguments after the command (output)
-	**cmd_  is the invoked command (output)
-	***args_ are the arguments after the command
-
-*/
-static int parse_args(int argc, char **argv,
-		      CommandFunction *func_,
-		      int *nargs_, char **cmd_, char ***args_ )
+int check_argc_min(int nargs, int expected)
 {
-	struct Command	*cp;
-	struct Command	*matchcmd=0;
-	char		*prgname = get_prgname(argv[0]);
-	int		i=0, helprequested=0;
-
-	if( argc < 2 || !strcmp(argv[1], "help") ||
-		!strcmp(argv[1], "-h") || !strcmp(argv[1], "--help")){
-		help(prgname);
-		return 0;
+	if (nargs < expected) {
+		fprintf(stderr, "%s: too few arguments\n", argv0_buf);
+		return 1;
 	}
 
-	for( cp = commands; cp->verb; cp++ )
-		if( !cp->ncmds)
-			cp->ncmds = split_command(cp->verb, &(cp->cmds));
+	return 0;
+}
 
-	for( cp = commands; cp->verb; cp++ ){
-		int     match;
+int check_argc_max(int nargs, int expected)
+{
+	if (nargs > expected) {
+		fprintf(stderr, "%s: too many arguments\n", argv0_buf);
+		return 1;
+	}
 
-		if( argc-1 < cp->ncmds )
-			continue;
-		for( match = 1, i = 0 ; i < cp->ncmds ; i++ ){
-			char	*s1, *s2;
-			s1 = cp->cmds[i];
-			s2 = argv[i+1];
-
-			for(s2 = cp->cmds[i], s1 = argv[i+1];
-				*s1 == *s2 && *s1;
-				s1++, s2++ ) ;
-			if( *s1 ){
-				match=0;
-				break;
-			}
-		}
+	return 0;
+}
 
-		/* If you understand why this code works ...
-			you are a genious !! */
-		if(argc>i+1 && !strcmp(argv[i+1],"--help")){
-			if(!helprequested)
-				printf("Usage:\n");
-			print_help(prgname, cp, ADVANCED_HELP);
-			helprequested=1;
-			continue;
-		}
+const struct cmd_group btrfs_cmd_group;
 
-		if(!match)
-			continue;
-
-		matchcmd = cp;
-		*nargs_  = argc-matchcmd->ncmds-1;
-		*cmd_ = matchcmd->verb;
-		*args_ = argv+matchcmd->ncmds+1;
-		*func_ = cp->func;
+static const char * const cmd_help_usage[] = {
+	"btrfs help [--full]",
+	"Dislay help information",
+	"",
+	"--full     display detailed help on every command",
+	NULL
+};
 
-		break;
-	}
+static int cmd_help(int argc, char **argv)
+{
+	help_command_group(&btrfs_cmd_group, argc, argv);
+	return 0;
+}
 
-	if(helprequested){
-		printf("\n%s\n", BTRFS_BUILD_VERSION);
-		return 0;
-	}
+static const char * const cmd_version_usage[] = {
+	"btrfs version",
+	"Display btrfs-progs version",
+	NULL
+};
 
-	if(!matchcmd){
-		fprintf( stderr, "ERROR: unknown command '%s'\n",argv[1]);
-		help(prgname);
-		return -1;
-	}
+static int cmd_version(int argc, char **argv)
+{
+	printf("%s\n", BTRFS_BUILD_VERSION);
+	return 0;
+}
 
-	if(check_ambiguity(matchcmd, argv))
-		return -2;
+static int handle_options(int *argc, char ***argv)
+{
+	char **orig_argv = *argv;
+
+	while (*argc > 0) {
+		const char *arg = (*argv)[0];
+		if (arg[0] != '-')
+			break;
+
+		if (!strcmp(arg, "--help")) {
+			break;
+		} else if (!strcmp(arg, "--version")) {
+			break;
+		} else {
+			fprintf(stderr, "Unknown option: %s\n", arg);
+			fprintf(stderr, "usage: %s\n",
+				btrfs_cmd_group.usagestr);
+			exit(129);
+		}
 
-	/* check the number of argument */
-	if (matchcmd->nargs < 0 && matchcmd->nargs < -*nargs_ ){
-		fprintf(stderr, "ERROR: '%s' requires minimum %d arg(s)\n",
-			matchcmd->verb, -matchcmd->nargs);
-			return -2;
-	}
-	if(matchcmd->nargs >= 0 && matchcmd->nargs != *nargs_ && matchcmd->nargs != 999){
-		fprintf(stderr, "ERROR: '%s' requires %d arg(s)\n",
-			matchcmd->verb, matchcmd->nargs);
-			return -2;
+		(*argv)++;
+		(*argc)--;
 	}
-	
-        if (prepare_args( nargs_, args_, prgname, matchcmd )){
-                fprintf(stderr, "ERROR: not enough memory\\n");
-		return -20;
-        }
-
 
-	return 1;
+	return (*argv) - orig_argv;
 }
-int main(int ac, char **av )
-{
 
-	char		*cmd=0, **args=0;
-	int		nargs=0, r;
-	CommandFunction func=0;
+const struct cmd_group btrfs_cmd_group = {
+	btrfs_cmd_group_usage, btrfs_cmd_group_info, {
+		{ "subvolume", cmd_subvolume, NULL, &subvolume_cmd_group, 0 },
+		{ "filesystem", cmd_filesystem, NULL, &filesystem_cmd_group, 0 },
+		{ "device", cmd_device, NULL, &device_cmd_group, 0 },
+		{ "scrub", cmd_scrub, NULL, &scrub_cmd_group, 0 },
+		{ "inspect-internal", cmd_inspect, NULL, &inspect_cmd_group, 0 },
+		{ "help", cmd_help, cmd_help_usage, NULL, 0 },
+		{ "version", cmd_version, cmd_version_usage, NULL, 0 },
+		{ 0, 0, 0, 0, 0 }
+	},
+};
 
-	r = parse_args(ac, av, &func, &nargs, &cmd, &args);
-	if( r <= 0 ){
-		/* error or no command to parse*/
-		exit(-r);
+int main(int argc, char **argv)
+{
+	const struct cmd_struct *cmd;
+
+	argc--;
+	argv++;
+	handle_options(&argc, &argv);
+	if (argc > 0) {
+		if (!prefixcmp(argv[0], "--"))
+			argv[0] += 2;
+	} else {
+		usage_command_group(&btrfs_cmd_group, 0, 0);
+		exit(1);
 	}
 
-	exit(func(nargs, args));
+	cmd = parse_command_token(argv[0], &btrfs_cmd_group);
 
-}
+	handle_help_options_next_level(cmd, argc, argv);
 
+	fixup_argv0(argv, cmd->token);
+	exit(cmd->fn(argc, argv));
+}
diff --git a/btrfs_cmds.c b/btrfs_cmds.c
deleted file mode 100644
index b59e9cb..0000000
--- a/btrfs_cmds.c
+++ /dev/null
@@ -1,1307 +0,0 @@
-/*
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public
- * License v2 as published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * General Public License for more details.
- *
- * You should have received a copy of the GNU General Public
- * License along with this program; if not, write to the
- * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
- * Boston, MA 021110-1307, USA.
- */
-
-
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <sys/ioctl.h>
-#include <sys/types.h>
-#include <dirent.h>
-#include <sys/stat.h>
-#include <unistd.h>
-#include <fcntl.h>
-#include <libgen.h>
-#include <limits.h>
-#include <uuid/uuid.h>
-#include <ctype.h>
-
-#undef ULONG_MAX
-
-#include "kerncompat.h"
-#include "ctree.h"
-#include "transaction.h"
-#include "utils.h"
-#include "version.h"
-#include "ioctl.h"
-#include "volumes.h"
-
-#include "btrfs_cmds.h"
-#include "btrfslabel.h"
-
-#ifdef __CHECKER__
-#define BLKGETSIZE64 0
-#define BTRFS_IOC_SNAP_CREATE_V2 0
-#define BTRFS_VOL_NAME_MAX 255
-struct btrfs_ioctl_vol_args { char name[BTRFS_VOL_NAME_MAX]; };
-static inline int ioctl(int fd, int define, void *arg) { return 0; }
-#endif
-
-/*
- * test if path is a subvolume:
- * this function return
- * 0-> path exists but it is not a subvolume
- * 1-> path exists and it is  a subvolume
- * -1 -> path is unaccessible
- */
-static int test_issubvolume(char *path)
-{
-
-	struct stat	st;
-	int		res;
-
-	res = stat(path, &st);
-	if(res < 0 )
-		return -1;
-
-	return (st.st_ino == 256) && S_ISDIR(st.st_mode);
-
-}
-
-/*
- * test if path is a directory
- * this function return
- * 0-> path exists but it is not a directory
- * 1-> path exists and it is  a directory
- * -1 -> path is unaccessible
- */
-static int test_isdir(char *path)
-{
-	struct stat	st;
-	int		res;
-
-	res = stat(path, &st);
-	if(res < 0 )
-		return -1;
-
-	return S_ISDIR(st.st_mode);
-
-}
-
-int open_file_or_dir(const char *fname)
-{
-	int ret;
-	struct stat st;
-	DIR *dirstream;
-	int fd;
-
-	ret = stat(fname, &st);
-	if (ret < 0) {
-		return -1;
-	}
-	if (S_ISDIR(st.st_mode)) {
-		dirstream = opendir(fname);
-		if (!dirstream) {
-			return -2;
-		}
-		fd = dirfd(dirstream);
-	} else {
-		fd = open(fname, O_RDWR);
-	}
-	if (fd < 0) {
-		return -3;
-	}
-	return fd;
-}
-
-static u64 parse_size(char *s)
-{
-	int len = strlen(s);
-	char c;
-	u64 mult = 1;
-
-	if (!isdigit(s[len - 1])) {
-		c = tolower(s[len - 1]);
-		switch (c) {
-		case 'g':
-			mult *= 1024;
-		case 'm':
-			mult *= 1024;
-		case 'k':
-			mult *= 1024;
-		case 'b':
-			break;
-		default:
-			fprintf(stderr, "Unknown size descriptor %c\n", c);
-			exit(1);
-		}
-		s[len - 1] = '\0';
-	}
-	return atoll(s) * mult;
-}
-
-static int parse_compress_type(char *s)
-{
-	if (strcmp(optarg, "zlib") == 0)
-		return BTRFS_COMPRESS_ZLIB;
-	else if (strcmp(optarg, "lzo") == 0)
-		return BTRFS_COMPRESS_LZO;
-	else {
-		fprintf(stderr, "Unknown compress type %s\n", s);
-		exit(1);
-	};
-}
-
-int do_defrag(int ac, char **av)
-{
-	int fd;
-	int flush = 0;
-	u64 start = 0;
-	u64 len = (u64)-1;
-	u32 thresh = 0;
-	int i;
-	int errors = 0;
-	int ret = 0;
-	int verbose = 0;
-	int fancy_ioctl = 0;
-	struct btrfs_ioctl_defrag_range_args range;
-	int e=0;
-	int compress_type = BTRFS_COMPRESS_NONE;
-
-	optind = 1;
-	while(1) {
-		int c = getopt(ac, av, "vc::fs:l:t:");
-		if (c < 0)
-			break;
-		switch(c) {
-		case 'c':
-			compress_type = BTRFS_COMPRESS_ZLIB;
-			if (optarg)
-				compress_type = parse_compress_type(optarg);
-			fancy_ioctl = 1;
-			break;
-		case 'f':
-			flush = 1;
-			fancy_ioctl = 1;
-			break;
-		case 'v':
-			verbose = 1;
-			break;
-		case 's':
-			start = parse_size(optarg);
-			fancy_ioctl = 1;
-			break;
-		case 'l':
-			len = parse_size(optarg);
-			fancy_ioctl = 1;
-			break;
-		case 't':
-			thresh = parse_size(optarg);
-			fancy_ioctl = 1;
-			break;
-		default:
-			fprintf(stderr, "Invalid arguments for defragment\n");
-			free(av);
-			return 1;
-		}
-	}
-	if (ac - optind == 0) {
-		fprintf(stderr, "Invalid arguments for defragment\n");
-		free(av);
-		return 1;
-	}
-
-	memset(&range, 0, sizeof(range));
-	range.start = start;
-	range.len = len;
-	range.extent_thresh = thresh;
-	if (compress_type) {
-		range.flags |= BTRFS_DEFRAG_RANGE_COMPRESS;
-		range.compress_type = compress_type;
-	}
-	if (flush)
-		range.flags |= BTRFS_DEFRAG_RANGE_START_IO;
-
-	for (i = optind; i < ac; i++) {
-		if (verbose)
-			printf("%s\n", av[i]);
-		fd = open_file_or_dir(av[i]);
-		if (fd < 0) {
-			fprintf(stderr, "failed to open %s\n", av[i]);
-			perror("open:");
-			errors++;
-			continue;
-		}
-		if (!fancy_ioctl) {
-			ret = ioctl(fd, BTRFS_IOC_DEFRAG, NULL);
-			e=errno;
-		} else {
-			ret = ioctl(fd, BTRFS_IOC_DEFRAG_RANGE, &range);
-			if (ret && errno == ENOTTY) {
-				fprintf(stderr, "ERROR: defrag range ioctl not "
-					"supported in this kernel, please try "
-					"without any options.\n");
-				errors++;
-				close(fd);
-				break;
-			}
-		}
-		if (ret) {
-			fprintf(stderr, "ERROR: defrag failed on %s - %s\n",
-				av[i], strerror(e));
-			errors++;
-		}
-		close(fd);
-	}
-	if (verbose)
-		printf("%s\n", BTRFS_BUILD_VERSION);
-	if (errors) {
-		fprintf(stderr, "total %d failures\n", errors);
-		exit(1);
-	}
-
-	free(av);
-	return errors + 20;
-}
-
-int do_find_newer(int argc, char **argv)
-{
-	int fd;
-	int ret;
-	char *subvol;
-	u64 last_gen;
-
-	subvol = argv[1];
-	last_gen = atoll(argv[2]);
-
-	ret = test_issubvolume(subvol);
-	if (ret < 0) {
-		fprintf(stderr, "ERROR: error accessing '%s'\n", subvol);
-		return 12;
-	}
-	if (!ret) {
-		fprintf(stderr, "ERROR: '%s' is not a subvolume\n", subvol);
-		return 13;
-	}
-
-	fd = open_file_or_dir(subvol);
-	if (fd < 0) {
-		fprintf(stderr, "ERROR: can't access '%s'\n", subvol);
-		return 12;
-	}
-	ret = find_updated_files(fd, 0, last_gen);
-	if (ret)
-		return 19;
-	return 0;
-}
-
-int do_subvol_list(int argc, char **argv)
-{
-	int fd;
-	int ret;
-	int print_parent = 0;
-	char *subvol;
-        int optind = 1;
-
-	while(1) {
-		int c = getopt(argc, argv, "p");
-		if (c < 0) break;
-		switch(c) {
-		case 'p':
-			print_parent = 1;
-			optind++;
-			break;
-		}
-	}
-	
-	if (argc - optind != 1) {
-		fprintf(stderr, "ERROR: invalid arguments for subvolume list\n");
-		return 1;
-	}
-
-	subvol = argv[optind];
-
-	ret = test_issubvolume(subvol);
-	if (ret < 0) {
-		fprintf(stderr, "ERROR: error accessing '%s'\n", subvol);
-		return 12;
-	}
-	if (!ret) {
-		fprintf(stderr, "ERROR: '%s' is not a subvolume\n", subvol);
-		return 13;
-	}
-
-	fd = open_file_or_dir(subvol);
-	if (fd < 0) {
-		fprintf(stderr, "ERROR: can't access '%s'\n", subvol);
-		return 12;
-	}
-	ret = list_subvols(fd, print_parent, 0);
-	if (ret)
-		return 19;
-	return 0;
-}
-
-int do_clone(int argc, char **argv)
-{
-	char	*subvol, *dst;
-	int	res, fd, fddst, len, e, optind = 0, readonly = 0;
-	char	*newname;
-	char	*dstdir;
-	struct btrfs_ioctl_vol_args_v2	args;
-
-	memset(&args, 0, sizeof(args));
-
-	while (1) {
-		int c = getopt(argc, argv, "r");
-
-		if (c < 0)
-			break;
-		switch (c) {
-		case 'r':
-			optind++;
-			readonly = 1;
-			break;
-		default:
-			fprintf(stderr,
-				"Invalid arguments for subvolume snapshot\n");
-			free(argv);
-			return 1;
-		}
-	}
-	if (argc - optind != 3) {
-		fprintf(stderr, "Invalid arguments for subvolume snapshot\n");
-		free(argv);
-		return 1;
-	}
-
-	subvol = argv[optind+1];
-	dst = argv[optind+2];
-
-	res = test_issubvolume(subvol);
-	if(res<0){
-		fprintf(stderr, "ERROR: error accessing '%s'\n", subvol);
-		return 12;
-	}
-	if(!res){
-		fprintf(stderr, "ERROR: '%s' is not a subvolume\n", subvol);
-		return 13;
-	}
-
-	res = test_isdir(dst);
-	if(res == 0 ){
-		fprintf(stderr, "ERROR: '%s' exists and it is not a directory\n", dst);
-		return 12;
-	}
-
-	if(res>0){
-		newname = strdup(subvol);
-		newname = basename(newname);
-		dstdir = dst;
-	}else{
-		newname = strdup(dst);
-		newname = basename(newname);
-		dstdir = strdup(dst);
-		dstdir = dirname(dstdir);
-	}
-
-	if( !strcmp(newname,".") || !strcmp(newname,"..") ||
-	     strchr(newname, '/') ){
-		fprintf(stderr, "ERROR: incorrect snapshot name ('%s')\n",
-			newname);
-		return 14;
-	}
-
-	len = strlen(newname);
-	if (len == 0 || len >= BTRFS_VOL_NAME_MAX) {
-		fprintf(stderr, "ERROR: snapshot name too long ('%s)\n",
-			newname);
-		return 14;
-	}
-
-	fddst = open_file_or_dir(dstdir);
-	if (fddst < 0) {
-		fprintf(stderr, "ERROR: can't access to '%s'\n", dstdir);
-		return 12;
-	}
-
-	fd = open_file_or_dir(subvol);
-	if (fd < 0) {
-		close(fddst);
-		fprintf(stderr, "ERROR: can't access to '%s'\n", dstdir);
-		return 12;
-	}
-
-	if (readonly) {
-		args.flags |= BTRFS_SUBVOL_RDONLY;
-		printf("Create a readonly snapshot of '%s' in '%s/%s'\n",
-		       subvol, dstdir, newname);
-	} else {
-		printf("Create a snapshot of '%s' in '%s/%s'\n",
-		       subvol, dstdir, newname);
-	}
-
-	args.fd = fd;
-	strncpy(args.name, newname, BTRFS_SUBVOL_NAME_MAX);
-	res = ioctl(fddst, BTRFS_IOC_SNAP_CREATE_V2, &args);
-	e = errno;
-
-	close(fd);
-	close(fddst);
-
-	if(res < 0 ){
-		fprintf( stderr, "ERROR: cannot snapshot '%s' - %s\n",
-			subvol, strerror(e));
-		return 11;
-	}
-
-	return 0;
-
-}
-
-int do_delete_subvolume(int argc, char **argv)
-{
-	int	res, fd, len, e;
-	struct btrfs_ioctl_vol_args	args;
-	char	*dname, *vname, *cpath;
-	char	*path = argv[1];
-
-	res = test_issubvolume(path);
-	if(res<0){
-		fprintf(stderr, "ERROR: error accessing '%s'\n", path);
-		return 12;
-	}
-	if(!res){
-		fprintf(stderr, "ERROR: '%s' is not a subvolume\n", path);
-		return 13;
-	}
-
-	cpath = realpath(path, 0);
-	dname = strdup(cpath);
-	dname = dirname(dname);
-	vname = strdup(cpath);
-	vname = basename(vname);
-	free(cpath);
-
-	if( !strcmp(vname,".") || !strcmp(vname,"..") ||
-	     strchr(vname, '/') ){
-		fprintf(stderr, "ERROR: incorrect subvolume name ('%s')\n",
-			vname);
-		return 14;
-	}
-
-	len = strlen(vname);
-	if (len == 0 || len >= BTRFS_VOL_NAME_MAX) {
-		fprintf(stderr, "ERROR: snapshot name too long ('%s)\n",
-			vname);
-		return 14;
-	}
-
-	fd = open_file_or_dir(dname);
-	if (fd < 0) {
-		close(fd);
-		fprintf(stderr, "ERROR: can't access to '%s'\n", dname);
-		return 12;
-	}
-
-	printf("Delete subvolume '%s/%s'\n", dname, vname);
-	strncpy(args.name, vname, BTRFS_PATH_NAME_MAX);
-	res = ioctl(fd, BTRFS_IOC_SNAP_DESTROY, &args);
-	e = errno;
-
-	close(fd);
-
-	if(res < 0 ){
-		fprintf( stderr, "ERROR: cannot delete '%s/%s' - %s\n",
-			dname, vname, strerror(e));
-		return 11;
-	}
-
-	return 0;
-
-}
-
-int do_create_subvol(int argc, char **argv)
-{
-	int	res, fddst, len, e;
-	char	*newname;
-	char	*dstdir;
-	struct btrfs_ioctl_vol_args	args;
-	char	*dst = argv[1];
-
-	res = test_isdir(dst);
-	if(res >= 0 ){
-		fprintf(stderr, "ERROR: '%s' exists\n", dst);
-		return 12;
-	}
-
-	newname = strdup(dst);
-	newname = basename(newname);
-	dstdir = strdup(dst);
-	dstdir = dirname(dstdir);
-
-	if( !strcmp(newname,".") || !strcmp(newname,"..") ||
-	     strchr(newname, '/') ){
-		fprintf(stderr, "ERROR: uncorrect subvolume name ('%s')\n",
-			newname);
-		return 14;
-	}
-
-	len = strlen(newname);
-	if (len == 0 || len >= BTRFS_VOL_NAME_MAX) {
-		fprintf(stderr, "ERROR: subvolume name too long ('%s)\n",
-			newname);
-		return 14;
-	}
-
-	fddst = open_file_or_dir(dstdir);
-	if (fddst < 0) {
-		fprintf(stderr, "ERROR: can't access to '%s'\n", dstdir);
-		return 12;
-	}
-
-	printf("Create subvolume '%s/%s'\n", dstdir, newname);
-	strncpy(args.name, newname, BTRFS_PATH_NAME_MAX);
-	res = ioctl(fddst, BTRFS_IOC_SUBVOL_CREATE, &args);
-	e = errno;
-
-	close(fddst);
-
-	if(res < 0 ){
-		fprintf( stderr, "ERROR: cannot create subvolume - %s\n",
-			strerror(e));
-		return 11;
-	}
-
-	return 0;
-
-}
-
-int do_fssync(int argc, char **argv)
-{
-	int 	fd, res, e;
-	char	*path = argv[1];
-
-	fd = open_file_or_dir(path);
-	if (fd < 0) {
-		fprintf(stderr, "ERROR: can't access to '%s'\n", path);
-		return 12;
-	}
-
-	printf("FSSync '%s'\n", path);
-	res = ioctl(fd, BTRFS_IOC_SYNC);
-	e = errno;
-	close(fd);
-	if( res < 0 ){
-		fprintf(stderr, "ERROR: unable to fs-syncing '%s' - %s\n", 
-			path, strerror(e));
-		return 16;
-	}
-
-	return 0;
-}
-
-int do_scan(int argc, char **argv)
-{
-	int	i, fd, e;
-	int	checklist = 1;
-	int	devstart = 1;
-
-	if( argc >= 2 && !strcmp(argv[1],"--all-devices")){
-
-		if( argc >2 ){
-			fprintf(stderr, "ERROR: too may arguments\n");
-                        return 22;
-                }
-
-		checklist = 0;
-		devstart += 1;
-	}
-
-	if(argc<=devstart){
-
-		int ret;
-
-		printf("Scanning for Btrfs filesystems\n");
-		if(checklist)
-			ret = btrfs_scan_block_devices(1);
-		else
-			ret = btrfs_scan_one_dir("/dev", 1);
-		if (ret){
-			fprintf(stderr, "ERROR: error %d while scanning\n", ret);
-			return 18;
-		}
-		return 0;
-	}
-
-	fd = open("/dev/btrfs-control", O_RDWR);
-	if (fd < 0) {
-		perror("failed to open /dev/btrfs-control");
-		return 10;
-	}
-
-	for( i = devstart ; i < argc ; i++ ){
-		struct btrfs_ioctl_vol_args args;
-		int ret;
-
-		printf("Scanning for Btrfs filesystems in '%s'\n", argv[i]);
-
-		strncpy(args.name, argv[i], BTRFS_PATH_NAME_MAX);
-		/*
-		 * FIXME: which are the error code returned by this ioctl ?
-		 * it seems that is impossible to understand if there no is
-		 * a btrfs filesystem from an I/O error !!!
-		 */
-		ret = ioctl(fd, BTRFS_IOC_SCAN_DEV, &args);
-		e = errno;
-
-		if( ret < 0 ){
-			close(fd);
-			fprintf(stderr, "ERROR: unable to scan the device '%s' - %s\n", 
-				argv[i], strerror(e));
-			return 11;
-		}
-	}
-
-	close(fd);
-	return 0;
-
-}
-
-int do_resize(int argc, char **argv)
-{
-
-	struct btrfs_ioctl_vol_args	args;
-	int	fd, res, len, e;
-	char	*amount=argv[1], *path=argv[2];
-
-	fd = open_file_or_dir(path);
-	if (fd < 0) {
-		fprintf(stderr, "ERROR: can't access to '%s'\n", path);
-		return 12;
-	}
-	len = strlen(amount);
-	if (len == 0 || len >= BTRFS_VOL_NAME_MAX) {
-		fprintf(stderr, "ERROR: size value too long ('%s)\n",
-			amount);
-		return 14;
-	}
-
-	printf("Resize '%s' of '%s'\n", path, amount);
-	strncpy(args.name, amount, BTRFS_PATH_NAME_MAX);
-	res = ioctl(fd, BTRFS_IOC_RESIZE, &args);
-	e = errno;
-	close(fd);
-	if( res < 0 ){
-		fprintf(stderr, "ERROR: unable to resize '%s' - %s\n", 
-			path, strerror(e));
-		return 30;
-	}
-	return 0;
-}
-
-static int uuid_search(struct btrfs_fs_devices *fs_devices, char *search)
-{
-	struct list_head *cur;
-	struct btrfs_device *device;
-
-	list_for_each(cur, &fs_devices->devices) {
-		device = list_entry(cur, struct btrfs_device, dev_list);
-		if ((device->label && strcmp(device->label, search) == 0) ||
-		    strcmp(device->name, search) == 0)
-			return 1;
-	}
-	return 0;
-}
-
-static void print_one_uuid(struct btrfs_fs_devices *fs_devices)
-{
-	char uuidbuf[37];
-	struct list_head *cur;
-	struct btrfs_device *device;
-	char *super_bytes_used;
-	u64 devs_found = 0;
-	u64 total;
-
-	uuid_unparse(fs_devices->fsid, uuidbuf);
-	device = list_entry(fs_devices->devices.next, struct btrfs_device,
-			    dev_list);
-	if (device->label && device->label[0])
-		printf("Label: '%s' ", device->label);
-	else
-		printf("Label: none ");
-
-	super_bytes_used = pretty_sizes(device->super_bytes_used);
-
-	total = device->total_devs;
-	printf(" uuid: %s\n\tTotal devices %llu FS bytes used %s\n", uuidbuf,
-	       (unsigned long long)total, super_bytes_used);
-
-	free(super_bytes_used);
-
-	list_for_each(cur, &fs_devices->devices) {
-		char *total_bytes;
-		char *bytes_used;
-		device = list_entry(cur, struct btrfs_device, dev_list);
-		total_bytes = pretty_sizes(device->total_bytes);
-		bytes_used = pretty_sizes(device->bytes_used);
-		printf("\tdevid %4llu size %s used %s path %s\n",
-		       (unsigned long long)device->devid,
-		       total_bytes, bytes_used, device->name);
-		free(total_bytes);
-		free(bytes_used);
-		devs_found++;
-	}
-	if (devs_found < total) {
-		printf("\t*** Some devices missing\n");
-	}
-	printf("\n");
-}
-
-int do_show_filesystem(int argc, char **argv)
-{
-	struct list_head *all_uuids;
-	struct btrfs_fs_devices *fs_devices;
-	struct list_head *cur_uuid;
-	char *search = 0;
-	int ret;
-	int checklist = 1;
-	int searchstart = 1;
-
-	if( argc >= 2 && !strcmp(argv[1],"--all-devices")){
-		checklist = 0;
-		searchstart += 1;
-	}
-
-	if( argc > searchstart+1 ){
-		fprintf(stderr, "ERROR: too many arguments\n");
-		return 22;
-	}	
-
-	if(checklist)
-		ret = btrfs_scan_block_devices(0);
-	else
-		ret = btrfs_scan_one_dir("/dev", 0);
-
-	if (ret){
-		fprintf(stderr, "ERROR: error %d while scanning\n", ret);
-		return 18;
-	}
-	
-	if(searchstart < argc)
-		search = argv[searchstart];
-
-	all_uuids = btrfs_scanned_uuids();
-	list_for_each(cur_uuid, all_uuids) {
-		fs_devices = list_entry(cur_uuid, struct btrfs_fs_devices,
-					list);
-		if (search && uuid_search(fs_devices, search) == 0)
-			continue;
-		print_one_uuid(fs_devices);
-	}
-	printf("%s\n", BTRFS_BUILD_VERSION);
-	return 0;
-}
-
-int do_add_volume(int nargs, char **args)
-{
-
-	char	*mntpnt = args[nargs-1];
-	int	i, fdmnt, ret=0, e;
-
-
-	fdmnt = open_file_or_dir(mntpnt);
-	if (fdmnt < 0) {
-		fprintf(stderr, "ERROR: can't access to '%s'\n", mntpnt);
-		return 12;
-	}
-
-	for (i = 1; i < (nargs-1); i++ ){
-		struct btrfs_ioctl_vol_args ioctl_args;
-		int	devfd, res;
-		u64 dev_block_count = 0;
-		struct stat st;
-		int mixed = 0;
-
-		res = check_mounted(args[i]);
-		if (res < 0) {
-			fprintf(stderr, "error checking %s mount status\n",
-				args[i]);
-			ret++;
-			continue;
-		}
-		if (res == 1) {
-			fprintf(stderr, "%s is mounted\n", args[i]);
-			ret++;
-			continue;
-		}
-
-		devfd = open(args[i], O_RDWR);
-		if (!devfd) {
-			fprintf(stderr, "ERROR: Unable to open device '%s'\n", args[i]);
-			close(devfd);
-			ret++;
-			continue;
-		}
-		res = fstat(devfd, &st);
-		if (res) {
-			fprintf(stderr, "ERROR: Unable to stat '%s'\n", args[i]);
-			close(devfd);
-			ret++;
-			continue;
-		}
-		if (!S_ISBLK(st.st_mode)) {
-			fprintf(stderr, "ERROR: '%s' is not a block device\n", args[i]);
-			close(devfd);
-			ret++;
-			continue;
-		}
-
-		res = btrfs_prepare_device(devfd, args[i], 1, &dev_block_count, &mixed);
-		if (res) {
-			fprintf(stderr, "ERROR: Unable to init '%s'\n", args[i]);
-			close(devfd);
-			ret++;
-			continue;
-		}
-		close(devfd);
-
-		strncpy(ioctl_args.name, args[i], BTRFS_PATH_NAME_MAX);
-		res = ioctl(fdmnt, BTRFS_IOC_ADD_DEV, &ioctl_args);
-		e = errno;
-		if(res<0){
-			fprintf(stderr, "ERROR: error adding the device '%s' - %s\n", 
-				args[i], strerror(e));
-			ret++;
-		}
-
-	}
-
-	close(fdmnt);
-	if (ret)
-		return ret+20;
-	else
-		return 0;
-
-}
-
-int do_balance(int argc, char **argv)
-{
-
-	int	fdmnt, ret=0, e;
-	struct btrfs_ioctl_vol_args args;
-	char	*path = argv[1];
-
-	fdmnt = open_file_or_dir(path);
-	if (fdmnt < 0) {
-		fprintf(stderr, "ERROR: can't access to '%s'\n", path);
-		return 12;
-	}
-
-	memset(&args, 0, sizeof(args));
-	ret = ioctl(fdmnt, BTRFS_IOC_BALANCE, &args);
-	e = errno;
-	close(fdmnt);
-	if(ret<0){
-		fprintf(stderr, "ERROR: error during balancing '%s' - %s\n", 
-			path, strerror(e));
-
-		return 19;
-	}
-	return 0;
-}
-int do_remove_volume(int nargs, char **args)
-{
-
-	char	*mntpnt = args[nargs-1];
-	int	i, fdmnt, ret=0, e;
-
-	fdmnt = open_file_or_dir(mntpnt);
-	if (fdmnt < 0) {
-		fprintf(stderr, "ERROR: can't access to '%s'\n", mntpnt);
-		return 12;
-	}
-
-	for(i=1 ; i < (nargs-1) ; i++ ){
-		struct	btrfs_ioctl_vol_args arg;
-		int	res;
-
-		strncpy(arg.name, args[i], BTRFS_PATH_NAME_MAX);
-		res = ioctl(fdmnt, BTRFS_IOC_RM_DEV, &arg);
-		e = errno;
-		if(res<0){
-			fprintf(stderr, "ERROR: error removing the device '%s' - %s\n", 
-				args[i], strerror(e));
-			ret++;
-		}
-	}
-
-	close(fdmnt);
-	if( ret)
-		return ret+20;
-	else
-		return 0;
-}
-
-int do_set_default_subvol(int nargs, char **argv)
-{
-	int	ret=0, fd, e;
-	u64	objectid;
-	char	*path = argv[2];
-	char	*subvolid = argv[1];
-
-	fd = open_file_or_dir(path);
-	if (fd < 0) {
-		fprintf(stderr, "ERROR: can't access to '%s'\n", path);
-		return 12;
-	}
-
-	objectid = (unsigned long long)strtoll(subvolid, NULL, 0);
-	if (errno == ERANGE) {
-		fprintf(stderr, "ERROR: invalid tree id (%s)\n",subvolid);
-		return 30;
-	}
-	ret = ioctl(fd, BTRFS_IOC_DEFAULT_SUBVOL, &objectid);
-	e = errno;
-	close(fd);
-	if( ret < 0 ){
-		fprintf(stderr, "ERROR: unable to set a new default subvolume - %s\n",
-			strerror(e));
-		return 30;
-	}
-	return 0;
-}
-
-int do_change_label(int nargs, char **argv)
-{
-	/* check the number of argument */
-	if ( nargs > 3 ){
-		fprintf(stderr, "ERROR: '%s' requires maximum 2 args\n",
-			argv[0]);
-		return -2;
-	}else if (nargs == 2){
-		return get_label(argv[1]);
-	} else {	/* nargs == 0 */
-		return set_label(argv[1], argv[2]);
-	}
-}
-
-
-int do_get_default_subvol(int nargs, char **argv)
-{
-	int fd;
-	int ret;
-	char *subvol;
-
-	subvol = argv[1];
-
-	ret = test_issubvolume(subvol);
-	if (ret < 0) {
-		fprintf(stderr, "ERROR: error accessing '%s'\n", subvol);
-		return 12;
-	}
-	if (!ret) {
-		fprintf(stderr, "ERROR: '%s' is not a subvolume\n", subvol);
-		return 13;
-	}
-
-	fd = open_file_or_dir(subvol);
-	if (fd < 0) {
-		fprintf(stderr, "ERROR: can't access '%s'\n", subvol);
-		return 12;
-	}
-	ret = list_subvols(fd, 0, 1);
-	if (ret)
-		return 19;
-	return 0;
-}
-
-int do_df_filesystem(int nargs, char **argv)
-{
-	struct btrfs_ioctl_space_args *sargs;
-	u64 count = 0, i;
-	int ret;
-	int fd;
-	int e;
-	char *path = argv[1];
-
-	fd = open_file_or_dir(path);
-	if (fd < 0) {
-		fprintf(stderr, "ERROR: can't access to '%s'\n", path);
-		return 12;
-	}
-
-	sargs = malloc(sizeof(struct btrfs_ioctl_space_args));
-	if (!sargs)
-		return -ENOMEM;
-
-	sargs->space_slots = 0;
-	sargs->total_spaces = 0;
-
-	ret = ioctl(fd, BTRFS_IOC_SPACE_INFO, sargs);
-	e = errno;
-	if (ret) {
-		fprintf(stderr, "ERROR: couldn't get space info on '%s' - %s\n",
-			path, strerror(e));
-		free(sargs);
-		return ret;
-	}
-	if (!sargs->total_spaces)
-		return 0;
-
-	count = sargs->total_spaces;
-
-	sargs = realloc(sargs, sizeof(struct btrfs_ioctl_space_args) +
-			(count * sizeof(struct btrfs_ioctl_space_info)));
-	if (!sargs)
-		return -ENOMEM;
-
-	sargs->space_slots = count;
-	sargs->total_spaces = 0;
-
-	ret = ioctl(fd, BTRFS_IOC_SPACE_INFO, sargs);
-	e = errno;
-	if (ret) {
-		fprintf(stderr, "ERROR: couldn't get space info on '%s' - %s\n",
-			path, strerror(e));
-		close(fd);
-		free(sargs);
-		return ret;
-	}
-
-	for (i = 0; i < sargs->total_spaces; i++) {
-		char description[80];
-		char *total_bytes;
-		char *used_bytes;
-		int written = 0;
-		u64 flags = sargs->spaces[i].flags;
-
-		memset(description, 0, 80);
-
-		if (flags & BTRFS_BLOCK_GROUP_DATA) {
-			if (flags & BTRFS_BLOCK_GROUP_METADATA) {
-				snprintf(description, 14, "%s",
-					 "Data+Metadata");
-				written += 13;
-			} else {
-				snprintf(description, 5, "%s", "Data");
-				written += 4;
-			}
-		} else if (flags & BTRFS_BLOCK_GROUP_SYSTEM) {
-			snprintf(description, 7, "%s", "System");
-			written += 6;
-		} else if (flags & BTRFS_BLOCK_GROUP_METADATA) {
-			snprintf(description, 9, "%s", "Metadata");
-			written += 8;
-		}
-
-		if (flags & BTRFS_BLOCK_GROUP_RAID0) {
-			snprintf(description+written, 8, "%s", ", RAID0");
-			written += 7;
-		} else if (flags & BTRFS_BLOCK_GROUP_RAID1) {
-			snprintf(description+written, 8, "%s", ", RAID1");
-			written += 7;
-		} else if (flags & BTRFS_BLOCK_GROUP_DUP) {
-			snprintf(description+written, 6, "%s", ", DUP");
-			written += 5;
-		} else if (flags & BTRFS_BLOCK_GROUP_RAID10) {
-			snprintf(description+written, 9, "%s", ", RAID10");
-			written += 8;
-		}
-
-		total_bytes = pretty_sizes(sargs->spaces[i].total_bytes);
-		used_bytes = pretty_sizes(sargs->spaces[i].used_bytes);
-		printf("%s: total=%s, used=%s\n", description, total_bytes,
-		       used_bytes);
-	}
-	free(sargs);
-
-	return 0;
-}
-
-static int __ino_to_path_fd(u64 inum, int fd, int verbose, const char *prepend)
-{
-	int ret;
-	int i;
-	struct btrfs_ioctl_ino_path_args ipa;
-	struct btrfs_data_container *fspath;
-
-	fspath = malloc(4096);
-	if (!fspath)
-		return 1;
-
-	ipa.inum = inum;
-	ipa.size = 4096;
-	ipa.fspath = (u64)fspath;
-
-	ret = ioctl(fd, BTRFS_IOC_INO_PATHS, &ipa);
-	if (ret) {
-		printf("ioctl ret=%d, error: %s\n", ret, strerror(errno));
-		goto out;
-	}
-
-	if (verbose)
-		printf("ioctl ret=%d, bytes_left=%lu, bytes_missing=%lu, "
-			"cnt=%d, missed=%d\n", ret,
-			(unsigned long)fspath->bytes_left,
-			(unsigned long)fspath->bytes_missing,
-			fspath->elem_cnt, fspath->elem_missed);
-
-	for (i = 0; i < fspath->elem_cnt; ++i) {
-		char **str = (char **)fspath->val;
-		str[i] += (unsigned long)fspath->val;
-		if (prepend)
-			printf("%s/%s\n", prepend, str[i]);
-		else
-			printf("%s\n", str[i]);
-	}
-
-out:
-	free(fspath);
-	return ret;
-}
-
-int do_ino_to_path(int nargs, char **argv)
-{
-	int fd;
-	int verbose = 0;
-
-	optind = 1;
-	while (1) {
-		int c = getopt(nargs, argv, "v");
-		if (c < 0)
-			break;
-		switch (c) {
-		case 'v':
-			verbose = 1;
-			break;
-		default:
-			fprintf(stderr, "invalid arguments for ipath\n");
-			return 1;
-		}
-	}
-	if (nargs - optind != 2) {
-		fprintf(stderr, "invalid arguments for ipath\n");
-		return 1;
-	}
-
-	fd = open_file_or_dir(argv[optind+1]);
-	if (fd < 0) {
-		fprintf(stderr, "ERROR: can't access '%s'\n", argv[optind+1]);
-		return 12;
-	}
-
-	return __ino_to_path_fd(atoll(argv[optind]), fd, verbose,
-				argv[optind+1]);
-}
-
-int do_logical_to_ino(int nargs, char **argv)
-{
-	int ret;
-	int fd;
-	int i;
-	int verbose = 0;
-	int getpath = 1;
-	int bytes_left;
-	struct btrfs_ioctl_logical_ino_args loi;
-	struct btrfs_data_container *inodes;
-	char full_path[4096];
-	char *path_ptr;
-
-	optind = 1;
-	while (1) {
-		int c = getopt(nargs, argv, "Pv");
-		if (c < 0)
-			break;
-		switch (c) {
-		case 'P':
-			getpath = 0;
-			break;
-		case 'v':
-			verbose = 1;
-			break;
-		default:
-			fprintf(stderr, "invalid arguments for ipath\n");
-			return 1;
-		}
-	}
-	if (nargs - optind != 2) {
-		fprintf(stderr, "invalid arguments for ipath\n");
-		return 1;
-	}
-
-	inodes = malloc(4096);
-	if (!inodes)
-		return 1;
-
-	loi.logical = atoll(argv[optind]);
-	loi.size = 4096;
-	loi.inodes = (u64)inodes;
-
-	fd = open_file_or_dir(argv[optind+1]);
-	if (fd < 0) {
-		fprintf(stderr, "ERROR: can't access '%s'\n", argv[optind+1]);
-		ret = 12;
-		goto out;
-	}
-
-	ret = ioctl(fd, BTRFS_IOC_LOGICAL_INO, &loi);
-	if (ret) {
-		printf("ioctl ret=%d, error: %s\n", ret, strerror(errno));
-		goto out;
-	}
-
-	if (verbose)
-		printf("ioctl ret=%d, bytes_left=%lu, bytes_missing=%lu, "
-			"cnt=%d, missed=%d\n", ret,
-			(unsigned long)inodes->bytes_left,
-			(unsigned long)inodes->bytes_missing,
-			inodes->elem_cnt, inodes->elem_missed);
-
-	bytes_left = sizeof(full_path);
-	ret = snprintf(full_path, bytes_left, "%s/", argv[optind+1]);
-	path_ptr = full_path + ret;
-	bytes_left -= ret + 1;
-	BUG_ON(bytes_left < 0);
-
-	for (i = 0; i < inodes->elem_cnt; i += 3) {
-		u64 inum = inodes->val[i];
-		u64 offset = inodes->val[i+1];
-		u64 root = inodes->val[i+2];
-		int path_fd;
-		char *name;
-
-		if (getpath) {
-			name = path_for_root(fd, root);
-			if (IS_ERR(name))
-				return PTR_ERR(name);
-			if (!name) {
-				path_ptr[-1] = '\0';
-				path_fd = fd;
-			} else {
-				path_ptr[-1] = '/';
-				ret = snprintf(path_ptr, bytes_left, "%s",
-						name);
-				BUG_ON(ret >= bytes_left);
-				free(name);
-				path_fd = open_file_or_dir(full_path);
-				if (path_fd < 0) {
-					fprintf(stderr, "ERROR: can't access "
-						"'%s'\n", full_path);
-					goto out;
-				}
-			}
-			__ino_to_path_fd(inum, path_fd, verbose, full_path);
-		} else {
-			printf("inode %llu offset %llu root %llu\n", inum,
-				offset, root);
-		}
-	}
-
-out:
-	free(inodes);
-	return ret;
-}
diff --git a/btrfs_cmds.h b/btrfs_cmds.h
deleted file mode 100644
index 81182b1..0000000
--- a/btrfs_cmds.h
+++ /dev/null
@@ -1,44 +0,0 @@
-/*
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public
- * License v2 as published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * General Public License for more details.
- *
- * You should have received a copy of the GNU General Public
- * License along with this program; if not, write to the
- * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
- * Boston, MA 021110-1307, USA.
- */
-
-/* btrfs_cmds.c*/
-int do_clone(int nargs, char **argv);
-int do_delete_subvolume(int nargs, char **argv);
-int do_create_subvol(int nargs, char **argv);
-int do_fssync(int nargs, char **argv);
-int do_defrag(int argc, char **argv);
-int do_show_filesystem(int nargs, char **argv);
-int do_add_volume(int nargs, char **args);
-int do_balance(int nargs, char **argv);
-int do_scrub_start(int nargs, char **argv);
-int do_scrub_status(int argc, char **argv);
-int do_scrub_resume(int argc, char **argv);
-int do_scrub_cancel(int nargs, char **argv);
-int do_remove_volume(int nargs, char **args);
-int do_scan(int nargs, char **argv);
-int do_resize(int nargs, char **argv);
-int do_subvol_list(int nargs, char **argv);
-int do_set_default_subvol(int nargs, char **argv);
-int do_get_default_subvol(int nargs, char **argv);
-int list_subvols(int fd, int print_parent, int get_default);
-int do_df_filesystem(int nargs, char **argv);
-int find_updated_files(int fd, u64 root_id, u64 oldest_gen);
-int do_find_newer(int argc, char **argv);
-int do_change_label(int argc, char **argv);
-int open_file_or_dir(const char *fname);
-int do_ino_to_path(int nargs, char **argv);
-int do_logical_to_ino(int nargs, char **argv);
-char *path_for_root(int fd, u64 root);
diff --git a/cmds-device.c b/cmds-device.c
new file mode 100644
index 0000000..51089ba
--- /dev/null
+++ b/cmds-device.c
@@ -0,0 +1,259 @@
+/*
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License v2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this program; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 021110-1307, USA.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/ioctl.h>
+#include <errno.h>
+#include <sys/stat.h>
+
+#include "kerncompat.h"
+#include "ctree.h"
+#include "ioctl.h"
+#include "utils.h"
+
+#include "commands.h"
+
+/* FIXME - imported cruft, fix sparse errors and warnings */
+#ifdef __CHECKER__
+#define BLKGETSIZE64 0
+#define BTRFS_IOC_SNAP_CREATE_V2 0
+#define BTRFS_VOL_NAME_MAX 255
+struct btrfs_ioctl_vol_args { char name[BTRFS_VOL_NAME_MAX]; };
+static inline int ioctl(int fd, int define, void *arg) { return 0; }
+#endif
+
+static const char device_cmd_group_usage[] =
+	"btrfs device <command> [<args>]";
+
+static const char * const cmd_add_dev_usage[] = {
+	"btrfs device add <device> [<device>...] <path>",
+	"Add a device to a filesystem",
+	NULL
+};
+
+static int cmd_add_dev(int argc, char **argv)
+{
+	char	*mntpnt;
+	int	i, fdmnt, ret=0, e;
+
+	if (check_argc_min(argc, 3))
+		usage(cmd_add_dev_usage);
+
+	mntpnt = argv[argc - 1];
+
+	fdmnt = open_file_or_dir(mntpnt);
+	if (fdmnt < 0) {
+		fprintf(stderr, "ERROR: can't access to '%s'\n", mntpnt);
+		return 12;
+	}
+
+	for (i = 1; i < argc - 1; i++ ){
+		struct btrfs_ioctl_vol_args ioctl_args;
+		int	devfd, res;
+		u64 dev_block_count = 0;
+		struct stat st;
+		int mixed = 0;
+
+		res = check_mounted(argv[i]);
+		if (res < 0) {
+			fprintf(stderr, "error checking %s mount status\n",
+				argv[i]);
+			ret++;
+			continue;
+		}
+		if (res == 1) {
+			fprintf(stderr, "%s is mounted\n", argv[i]);
+			ret++;
+			continue;
+		}
+
+		devfd = open(argv[i], O_RDWR);
+		if (!devfd) {
+			fprintf(stderr, "ERROR: Unable to open device '%s'\n", argv[i]);
+			close(devfd);
+			ret++;
+			continue;
+		}
+		res = fstat(devfd, &st);
+		if (res) {
+			fprintf(stderr, "ERROR: Unable to stat '%s'\n", argv[i]);
+			close(devfd);
+			ret++;
+			continue;
+		}
+		if (!S_ISBLK(st.st_mode)) {
+			fprintf(stderr, "ERROR: '%s' is not a block device\n", argv[i]);
+			close(devfd);
+			ret++;
+			continue;
+		}
+
+		res = btrfs_prepare_device(devfd, argv[i], 1, &dev_block_count, &mixed);
+		if (res) {
+			fprintf(stderr, "ERROR: Unable to init '%s'\n", argv[i]);
+			close(devfd);
+			ret++;
+			continue;
+		}
+		close(devfd);
+
+		strncpy(ioctl_args.name, argv[i], BTRFS_PATH_NAME_MAX);
+		res = ioctl(fdmnt, BTRFS_IOC_ADD_DEV, &ioctl_args);
+		e = errno;
+		if(res<0){
+			fprintf(stderr, "ERROR: error adding the device '%s' - %s\n",
+				argv[i], strerror(e));
+			ret++;
+		}
+
+	}
+
+	close(fdmnt);
+	if (ret)
+		return ret+20;
+	else
+		return 0;
+}
+
+static const char * const cmd_rm_dev_usage[] = {
+	"btrfs device delete <device> [<device>...] <path>",
+	"Remove a device from a filesystem",
+	NULL
+};
+
+static int cmd_rm_dev(int argc, char **argv)
+{
+	char	*mntpnt;
+	int	i, fdmnt, ret=0, e;
+
+	if (check_argc_min(argc, 3))
+		usage(cmd_rm_dev_usage);
+
+	mntpnt = argv[argc - 1];
+
+	fdmnt = open_file_or_dir(mntpnt);
+	if (fdmnt < 0) {
+		fprintf(stderr, "ERROR: can't access to '%s'\n", mntpnt);
+		return 12;
+	}
+
+	for(i=1 ; i < argc - 1; i++ ){
+		struct	btrfs_ioctl_vol_args arg;
+		int	res;
+
+		strncpy(arg.name, argv[i], BTRFS_PATH_NAME_MAX);
+		res = ioctl(fdmnt, BTRFS_IOC_RM_DEV, &arg);
+		e = errno;
+		if(res<0){
+			fprintf(stderr, "ERROR: error removing the device '%s' - %s\n",
+				argv[i], strerror(e));
+			ret++;
+		}
+	}
+
+	close(fdmnt);
+	if( ret)
+		return ret+20;
+	else
+		return 0;
+}
+
+static const char * const cmd_scan_dev_usage[] = {
+	"btrfs device scan [<device>...]",
+	"Scan devices for a btrfs filesystem",
+	NULL
+};
+
+static int cmd_scan_dev(int argc, char **argv)
+{
+	int	i, fd, e;
+	int	checklist = 1;
+	int	devstart = 1;
+
+	if( argc > 1 && !strcmp(argv[1],"--all-devices")){
+		if (check_argc_max(argc, 2))
+			usage(cmd_scan_dev_usage);
+
+		checklist = 0;
+		devstart += 1;
+	}
+
+	if(argc<=devstart){
+
+		int ret;
+
+		printf("Scanning for Btrfs filesystems\n");
+		if(checklist)
+			ret = btrfs_scan_block_devices(1);
+		else
+			ret = btrfs_scan_one_dir("/dev", 1);
+		if (ret){
+			fprintf(stderr, "ERROR: error %d while scanning\n", ret);
+			return 18;
+		}
+		return 0;
+	}
+
+	fd = open("/dev/btrfs-control", O_RDWR);
+	if (fd < 0) {
+		perror("failed to open /dev/btrfs-control");
+		return 10;
+	}
+
+	for( i = devstart ; i < argc ; i++ ){
+		struct btrfs_ioctl_vol_args args;
+		int ret;
+
+		printf("Scanning for Btrfs filesystems in '%s'\n", argv[i]);
+
+		strncpy(args.name, argv[i], BTRFS_PATH_NAME_MAX);
+		/*
+		 * FIXME: which are the error code returned by this ioctl ?
+		 * it seems that is impossible to understand if there no is
+		 * a btrfs filesystem from an I/O error !!!
+		 */
+		ret = ioctl(fd, BTRFS_IOC_SCAN_DEV, &args);
+		e = errno;
+
+		if( ret < 0 ){
+			close(fd);
+			fprintf(stderr, "ERROR: unable to scan the device '%s' - %s\n",
+				argv[i], strerror(e));
+			return 11;
+		}
+	}
+
+	close(fd);
+	return 0;
+}
+
+const struct cmd_group device_cmd_group = {
+	device_cmd_group_usage, NULL, {
+		{ "add", cmd_add_dev, cmd_add_dev_usage, NULL, 0 },
+		{ "delete", cmd_rm_dev, cmd_rm_dev_usage, NULL, 0 },
+		{ "scan", cmd_scan_dev, cmd_scan_dev_usage, NULL, 0 },
+		{ 0, 0, 0, 0, 0 }
+	}
+};
+
+int cmd_device(int argc, char **argv)
+{
+	return handle_command_group(&device_cmd_group, argc, argv);
+}
diff --git a/cmds-filesystem.c b/cmds-filesystem.c
new file mode 100644
index 0000000..828ca0c
--- /dev/null
+++ b/cmds-filesystem.c
@@ -0,0 +1,572 @@
+/*
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License v2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this program; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 021110-1307, USA.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/ioctl.h>
+#include <errno.h>
+#include <uuid/uuid.h>
+#include <ctype.h>
+
+#include "kerncompat.h"
+#include "ctree.h"
+#include "ioctl.h"
+#include "utils.h"
+#include "volumes.h"
+
+#include "version.h"
+
+#include "commands.h"
+#include "btrfslabel.h"
+
+static const char filesystem_cmd_group_usage[] =
+	"btrfs filesystem [<group>] <command> [<args>]";
+
+static const char * const cmd_df_usage[] = {
+	"btrfs filesystem df <path>",
+	"Show space usage information for a mount point",
+	NULL
+};
+
+static int cmd_df(int argc, char **argv)
+{
+	struct btrfs_ioctl_space_args *sargs;
+	u64 count = 0, i;
+	int ret;
+	int fd;
+	int e;
+	char *path;
+
+	if (check_argc_exact(argc, 2))
+		usage(cmd_df_usage);
+
+	path = argv[1];
+
+	fd = open_file_or_dir(path);
+	if (fd < 0) {
+		fprintf(stderr, "ERROR: can't access to '%s'\n", path);
+		return 12;
+	}
+
+	sargs = malloc(sizeof(struct btrfs_ioctl_space_args));
+	if (!sargs)
+		return -ENOMEM;
+
+	sargs->space_slots = 0;
+	sargs->total_spaces = 0;
+
+	ret = ioctl(fd, BTRFS_IOC_SPACE_INFO, sargs);
+	e = errno;
+	if (ret) {
+		fprintf(stderr, "ERROR: couldn't get space info on '%s' - %s\n",
+			path, strerror(e));
+		free(sargs);
+		return ret;
+	}
+	if (!sargs->total_spaces)
+		return 0;
+
+	count = sargs->total_spaces;
+
+	sargs = realloc(sargs, sizeof(struct btrfs_ioctl_space_args) +
+			(count * sizeof(struct btrfs_ioctl_space_info)));
+	if (!sargs)
+		return -ENOMEM;
+
+	sargs->space_slots = count;
+	sargs->total_spaces = 0;
+
+	ret = ioctl(fd, BTRFS_IOC_SPACE_INFO, sargs);
+	e = errno;
+	if (ret) {
+		fprintf(stderr, "ERROR: couldn't get space info on '%s' - %s\n",
+			path, strerror(e));
+		close(fd);
+		free(sargs);
+		return ret;
+	}
+
+	for (i = 0; i < sargs->total_spaces; i++) {
+		char description[80];
+		char *total_bytes;
+		char *used_bytes;
+		int written = 0;
+		u64 flags = sargs->spaces[i].flags;
+
+		memset(description, 0, 80);
+
+		if (flags & BTRFS_BLOCK_GROUP_DATA) {
+			if (flags & BTRFS_BLOCK_GROUP_METADATA) {
+				snprintf(description, 14, "%s",
+					 "Data+Metadata");
+				written += 13;
+			} else {
+				snprintf(description, 5, "%s", "Data");
+				written += 4;
+			}
+		} else if (flags & BTRFS_BLOCK_GROUP_SYSTEM) {
+			snprintf(description, 7, "%s", "System");
+			written += 6;
+		} else if (flags & BTRFS_BLOCK_GROUP_METADATA) {
+			snprintf(description, 9, "%s", "Metadata");
+			written += 8;
+		}
+
+		if (flags & BTRFS_BLOCK_GROUP_RAID0) {
+			snprintf(description+written, 8, "%s", ", RAID0");
+			written += 7;
+		} else if (flags & BTRFS_BLOCK_GROUP_RAID1) {
+			snprintf(description+written, 8, "%s", ", RAID1");
+			written += 7;
+		} else if (flags & BTRFS_BLOCK_GROUP_DUP) {
+			snprintf(description+written, 6, "%s", ", DUP");
+			written += 5;
+		} else if (flags & BTRFS_BLOCK_GROUP_RAID10) {
+			snprintf(description+written, 9, "%s", ", RAID10");
+			written += 8;
+		}
+
+		total_bytes = pretty_sizes(sargs->spaces[i].total_bytes);
+		used_bytes = pretty_sizes(sargs->spaces[i].used_bytes);
+		printf("%s: total=%s, used=%s\n", description, total_bytes,
+		       used_bytes);
+	}
+	free(sargs);
+
+	return 0;
+}
+
+static int uuid_search(struct btrfs_fs_devices *fs_devices, char *search)
+{
+	struct list_head *cur;
+	struct btrfs_device *device;
+
+	list_for_each(cur, &fs_devices->devices) {
+		device = list_entry(cur, struct btrfs_device, dev_list);
+		if ((device->label && strcmp(device->label, search) == 0) ||
+		    strcmp(device->name, search) == 0)
+			return 1;
+	}
+	return 0;
+}
+
+static void print_one_uuid(struct btrfs_fs_devices *fs_devices)
+{
+	char uuidbuf[37];
+	struct list_head *cur;
+	struct btrfs_device *device;
+	char *super_bytes_used;
+	u64 devs_found = 0;
+	u64 total;
+
+	uuid_unparse(fs_devices->fsid, uuidbuf);
+	device = list_entry(fs_devices->devices.next, struct btrfs_device,
+			    dev_list);
+	if (device->label && device->label[0])
+		printf("Label: '%s' ", device->label);
+	else
+		printf("Label: none ");
+
+	super_bytes_used = pretty_sizes(device->super_bytes_used);
+
+	total = device->total_devs;
+	printf(" uuid: %s\n\tTotal devices %llu FS bytes used %s\n", uuidbuf,
+	       (unsigned long long)total, super_bytes_used);
+
+	free(super_bytes_used);
+
+	list_for_each(cur, &fs_devices->devices) {
+		char *total_bytes;
+		char *bytes_used;
+		device = list_entry(cur, struct btrfs_device, dev_list);
+		total_bytes = pretty_sizes(device->total_bytes);
+		bytes_used = pretty_sizes(device->bytes_used);
+		printf("\tdevid %4llu size %s used %s path %s\n",
+		       (unsigned long long)device->devid,
+		       total_bytes, bytes_used, device->name);
+		free(total_bytes);
+		free(bytes_used);
+		devs_found++;
+	}
+	if (devs_found < total) {
+		printf("\t*** Some devices missing\n");
+	}
+	printf("\n");
+}
+
+static const char * const cmd_show_usage[] = {
+	"btrfs filesystem show [--all-devices] [<uuid>|<label>]",
+	"Show the structure of a filesystem",
+	"If no argument is given, structure of all present filesystems is shown.",
+	NULL
+};
+
+static int cmd_show(int argc, char **argv)
+{
+	struct list_head *all_uuids;
+	struct btrfs_fs_devices *fs_devices;
+	struct list_head *cur_uuid;
+	char *search = 0;
+	int ret;
+	int checklist = 1;
+	int searchstart = 1;
+
+	if( argc > 1 && !strcmp(argv[1],"--all-devices")){
+		checklist = 0;
+		searchstart += 1;
+	}
+
+	if (check_argc_max(argc, searchstart + 1))
+		usage(cmd_show_usage);
+
+	if(checklist)
+		ret = btrfs_scan_block_devices(0);
+	else
+		ret = btrfs_scan_one_dir("/dev", 0);
+
+	if (ret){
+		fprintf(stderr, "ERROR: error %d while scanning\n", ret);
+		return 18;
+	}
+	
+	if(searchstart < argc)
+		search = argv[searchstart];
+
+	all_uuids = btrfs_scanned_uuids();
+	list_for_each(cur_uuid, all_uuids) {
+		fs_devices = list_entry(cur_uuid, struct btrfs_fs_devices,
+					list);
+		if (search && uuid_search(fs_devices, search) == 0)
+			continue;
+		print_one_uuid(fs_devices);
+	}
+	printf("%s\n", BTRFS_BUILD_VERSION);
+	return 0;
+}
+
+static const char * const cmd_sync_usage[] = {
+	"btrfs filesystem sync <path>",
+	"Force a sync on a filesystem",
+	NULL
+};
+
+static int cmd_sync(int argc, char **argv)
+{
+	int 	fd, res, e;
+	char	*path;
+
+	if (check_argc_exact(argc, 2))
+		usage(cmd_sync_usage);
+
+	path = argv[1];
+
+	fd = open_file_or_dir(path);
+	if (fd < 0) {
+		fprintf(stderr, "ERROR: can't access to '%s'\n", path);
+		return 12;
+	}
+
+	printf("FSSync '%s'\n", path);
+	res = ioctl(fd, BTRFS_IOC_SYNC);
+	e = errno;
+	close(fd);
+	if( res < 0 ){
+		fprintf(stderr, "ERROR: unable to fs-syncing '%s' - %s\n", 
+			path, strerror(e));
+		return 16;
+	}
+
+	return 0;
+}
+
+static u64 parse_size(char *s)
+{
+	int len = strlen(s);
+	char c;
+	u64 mult = 1;
+
+	if (!isdigit(s[len - 1])) {
+		c = tolower(s[len - 1]);
+		switch (c) {
+		case 'g':
+			mult *= 1024;
+		case 'm':
+			mult *= 1024;
+		case 'k':
+			mult *= 1024;
+		case 'b':
+			break;
+		default:
+			fprintf(stderr, "Unknown size descriptor %c\n", c);
+			exit(1);
+		}
+		s[len - 1] = '\0';
+	}
+	return atoll(s) * mult;
+}
+
+static int parse_compress_type(char *s)
+{
+	if (strcmp(optarg, "zlib") == 0)
+		return BTRFS_COMPRESS_ZLIB;
+	else if (strcmp(optarg, "lzo") == 0)
+		return BTRFS_COMPRESS_LZO;
+	else {
+		fprintf(stderr, "Unknown compress type %s\n", s);
+		exit(1);
+	};
+}
+
+static const char * const cmd_defrag_usage[] = {
+	"btrfs filesystem defragment [options] <file>|<dir> [<file>|<dir>...]",
+	"Defragment a file or a directory",
+	"",
+	"-v             be verbose",
+	"-c[zlib,lzo]   compress the file while defragmenting",
+	"-f             flush data to disk immediately after defragmenting",
+	"-s start       defragment only from byte onward",
+	"-l len         defragment only up to len bytes",
+	"-t size        minimal size of file to be considered for defragmenting",
+	NULL
+};
+
+static int cmd_defrag(int argc, char **argv)
+{
+	int fd;
+	int flush = 0;
+	u64 start = 0;
+	u64 len = (u64)-1;
+	u32 thresh = 0;
+	int i;
+	int errors = 0;
+	int ret = 0;
+	int verbose = 0;
+	int fancy_ioctl = 0;
+	struct btrfs_ioctl_defrag_range_args range;
+	int e=0;
+	int compress_type = BTRFS_COMPRESS_NONE;
+
+	optind = 1;
+	while(1) {
+		int c = getopt(argc, argv, "vc::fs:l:t:");
+		if (c < 0)
+			break;
+
+		switch(c) {
+		case 'c':
+			compress_type = BTRFS_COMPRESS_ZLIB;
+			if (optarg)
+				compress_type = parse_compress_type(optarg);
+			fancy_ioctl = 1;
+			break;
+		case 'f':
+			flush = 1;
+			fancy_ioctl = 1;
+			break;
+		case 'v':
+			verbose = 1;
+			break;
+		case 's':
+			start = parse_size(optarg);
+			fancy_ioctl = 1;
+			break;
+		case 'l':
+			len = parse_size(optarg);
+			fancy_ioctl = 1;
+			break;
+		case 't':
+			thresh = parse_size(optarg);
+			fancy_ioctl = 1;
+			break;
+		default:
+			usage(cmd_defrag_usage);
+		}
+	}
+
+	if (check_argc_min(argc - optind, 1))
+		usage(cmd_defrag_usage);
+
+	memset(&range, 0, sizeof(range));
+	range.start = start;
+	range.len = len;
+	range.extent_thresh = thresh;
+	if (compress_type) {
+		range.flags |= BTRFS_DEFRAG_RANGE_COMPRESS;
+		range.compress_type = compress_type;
+	}
+	if (flush)
+		range.flags |= BTRFS_DEFRAG_RANGE_START_IO;
+
+	for (i = optind; i < argc; i++) {
+		if (verbose)
+			printf("%s\n", argv[i]);
+		fd = open_file_or_dir(argv[i]);
+		if (fd < 0) {
+			fprintf(stderr, "failed to open %s\n", argv[i]);
+			perror("open:");
+			errors++;
+			continue;
+		}
+		if (!fancy_ioctl) {
+			ret = ioctl(fd, BTRFS_IOC_DEFRAG, NULL);
+			e=errno;
+		} else {
+			ret = ioctl(fd, BTRFS_IOC_DEFRAG_RANGE, &range);
+			if (ret && errno == ENOTTY) {
+				fprintf(stderr, "ERROR: defrag range ioctl not "
+					"supported in this kernel, please try "
+					"without any options.\n");
+				errors++;
+				close(fd);
+				break;
+			}
+		}
+		if (ret) {
+			fprintf(stderr, "ERROR: defrag failed on %s - %s\n",
+				argv[i], strerror(e));
+			errors++;
+		}
+		close(fd);
+	}
+	if (verbose)
+		printf("%s\n", BTRFS_BUILD_VERSION);
+	if (errors) {
+		fprintf(stderr, "total %d failures\n", errors);
+		exit(1);
+	}
+
+	return errors + 20;
+}
+
+static const char * const cmd_balance_usage[] = {
+	"btrfs filesystem balance <path>",
+	"Balance the chunks across the device",
+	NULL
+};
+
+static int cmd_balance(int argc, char **argv)
+{
+	int	fdmnt, ret=0, e;
+	struct btrfs_ioctl_vol_args args;
+	char	*path;
+
+	if (check_argc_exact(argc, 2))
+		usage(cmd_balance_usage);
+
+	path = argv[1];
+
+	fdmnt = open_file_or_dir(path);
+	if (fdmnt < 0) {
+		fprintf(stderr, "ERROR: can't access to '%s'\n", path);
+		return 12;
+	}
+
+	memset(&args, 0, sizeof(args));
+	ret = ioctl(fdmnt, BTRFS_IOC_BALANCE, &args);
+	e = errno;
+	close(fdmnt);
+	if(ret<0){
+		fprintf(stderr, "ERROR: error during balancing '%s' - %s\n", 
+			path, strerror(e));
+
+		return 19;
+	}
+	return 0;
+}
+
+static const char * const cmd_resize_usage[] = {
+	"btrfs filesystem resize [+/-]<newsize>[gkm]|max <path>",
+	"Resize a filesystem",
+	"If 'max' is passed, the filesystem will occupy all available space",
+	"on the device.",
+	NULL
+};
+
+static int cmd_resize(int argc, char **argv)
+{
+	struct btrfs_ioctl_vol_args	args;
+	int	fd, res, len, e;
+	char	*amount, *path;
+
+	if (check_argc_exact(argc, 3))
+		usage(cmd_resize_usage);
+
+	amount = argv[1];
+	path = argv[2];
+
+	fd = open_file_or_dir(path);
+	if (fd < 0) {
+		fprintf(stderr, "ERROR: can't access to '%s'\n", path);
+		return 12;
+	}
+	len = strlen(amount);
+	if (len == 0 || len >= BTRFS_VOL_NAME_MAX) {
+		fprintf(stderr, "ERROR: size value too long ('%s)\n",
+			amount);
+		return 14;
+	}
+
+	printf("Resize '%s' of '%s'\n", path, amount);
+	strncpy(args.name, amount, BTRFS_PATH_NAME_MAX);
+	res = ioctl(fd, BTRFS_IOC_RESIZE, &args);
+	e = errno;
+	close(fd);
+	if( res < 0 ){
+		fprintf(stderr, "ERROR: unable to resize '%s' - %s\n", 
+			path, strerror(e));
+		return 30;
+	}
+	return 0;
+}
+
+static const char * const cmd_label_usage[] = {
+	"btrfs filesystem label <device> [<newlabel>]",
+	"Get or change the label of an unmounted filesystem",
+	"With one argument, get the label of filesystem on <device>.",
+	"If <newlabel> is passed, set the filesystem label to <newlabel>.",
+	NULL
+};
+
+static int cmd_label(int argc, char **argv)
+{
+	if (check_argc_min(argc, 2) || check_argc_max(argc, 3))
+		usage(cmd_label_usage);
+
+	if (argc > 2)
+		return set_label(argv[1], argv[2]);
+	else
+		return get_label(argv[1]);
+}
+
+const struct cmd_group filesystem_cmd_group = {
+	filesystem_cmd_group_usage, NULL, {
+		{ "df", cmd_df, cmd_df_usage, NULL, 0 },
+		{ "show", cmd_show, cmd_show_usage, NULL, 0 },
+		{ "sync", cmd_sync, cmd_sync_usage, NULL, 0 },
+		{ "defragment", cmd_defrag, cmd_defrag_usage, NULL, 0 },
+		{ "balance", cmd_balance, cmd_balance_usage, NULL, 0 },
+		{ "resize", cmd_resize, cmd_resize_usage, NULL, 0 },
+		{ "label", cmd_label, cmd_label_usage, NULL, 0 },
+		{ 0, 0, 0, 0, 0 },
+	}
+};
+
+int cmd_filesystem(int argc, char **argv)
+{
+	return handle_command_group(&filesystem_cmd_group, argc, argv);
+}
diff --git a/cmds-inspect.c b/cmds-inspect.c
new file mode 100644
index 0000000..6cf565d
--- /dev/null
+++ b/cmds-inspect.c
@@ -0,0 +1,241 @@
+/*
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License v2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this program; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 021110-1307, USA.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <sys/ioctl.h>
+#include <errno.h>
+
+#include "kerncompat.h"
+#include "ioctl.h"
+
+#include "commands.h"
+
+/* btrfs-list.c */
+char *path_for_root(int fd, u64 root);
+
+static const char inspect_cmd_group_usage[] =
+	"btrfs inspect-internal <command> <args>";
+
+static int __ino_to_path_fd(u64 inum, int fd, int verbose, const char *prepend)
+{
+	int ret;
+	int i;
+	struct btrfs_ioctl_ino_path_args ipa;
+	struct btrfs_data_container *fspath;
+
+	fspath = malloc(4096);
+	if (!fspath)
+		return 1;
+
+	ipa.inum = inum;
+	ipa.size = 4096;
+	ipa.fspath = (u64)fspath;
+
+	ret = ioctl(fd, BTRFS_IOC_INO_PATHS, &ipa);
+	if (ret) {
+		printf("ioctl ret=%d, error: %s\n", ret, strerror(errno));
+		goto out;
+	}
+
+	if (verbose)
+		printf("ioctl ret=%d, bytes_left=%lu, bytes_missing=%lu, "
+			"cnt=%d, missed=%d\n", ret,
+			(unsigned long)fspath->bytes_left,
+			(unsigned long)fspath->bytes_missing,
+			fspath->elem_cnt, fspath->elem_missed);
+
+	for (i = 0; i < fspath->elem_cnt; ++i) {
+		char **str = (char **)fspath->val;
+		str[i] += (unsigned long)fspath->val;
+		if (prepend)
+			printf("%s/%s\n", prepend, str[i]);
+		else
+			printf("%s\n", str[i]);
+	}
+
+out:
+	free(fspath);
+	return ret;
+}
+
+static const char * const cmd_inode_resolve_usage[] = {
+	"btrfs inspect-internal inode-resolve [-v] <inode> <path>",
+	"Get file system paths for the given inode",
+	NULL
+};
+
+static int cmd_inode_resolve(int argc, char **argv)
+{
+	int fd;
+	int verbose = 0;
+
+	optind = 1;
+	while (1) {
+		int c = getopt(argc, argv, "v");
+		if (c < 0)
+			break;
+
+		switch (c) {
+		case 'v':
+			verbose = 1;
+			break;
+		default:
+			usage(cmd_inode_resolve_usage);
+		}
+	}
+
+	if (check_argc_exact(argc - optind, 2))
+		usage(cmd_inode_resolve_usage);
+
+	fd = open_file_or_dir(argv[optind+1]);
+	if (fd < 0) {
+		fprintf(stderr, "ERROR: can't access '%s'\n", argv[optind+1]);
+		return 12;
+	}
+
+	return __ino_to_path_fd(atoll(argv[optind]), fd, verbose,
+				argv[optind+1]);
+}
+
+static const char * const cmd_logical_resolve_usage[] = {
+	"btrfs inspect-internal logical-resolve [-Pv] <logical> <path>",
+	"Get file system paths for the given logical address",
+	NULL
+};
+
+static int cmd_logical_resolve(int argc, char **argv)
+{
+	int ret;
+	int fd;
+	int i;
+	int verbose = 0;
+	int getpath = 1;
+	int bytes_left;
+	struct btrfs_ioctl_logical_ino_args loi;
+	struct btrfs_data_container *inodes;
+	char full_path[4096];
+	char *path_ptr;
+
+	optind = 1;
+	while (1) {
+		int c = getopt(argc, argv, "Pv");
+		if (c < 0)
+			break;
+
+		switch (c) {
+		case 'P':
+			getpath = 0;
+			break;
+		case 'v':
+			verbose = 1;
+			break;
+		default:
+			usage(cmd_logical_resolve_usage);
+		}
+	}
+
+	if (check_argc_exact(argc - optind, 2))
+		usage(cmd_logical_resolve_usage);
+
+	inodes = malloc(4096);
+	if (!inodes)
+		return 1;
+
+	loi.logical = atoll(argv[optind]);
+	loi.size = 4096;
+	loi.inodes = (u64)inodes;
+
+	fd = open_file_or_dir(argv[optind+1]);
+	if (fd < 0) {
+		fprintf(stderr, "ERROR: can't access '%s'\n", argv[optind+1]);
+		ret = 12;
+		goto out;
+	}
+
+	ret = ioctl(fd, BTRFS_IOC_LOGICAL_INO, &loi);
+	if (ret) {
+		printf("ioctl ret=%d, error: %s\n", ret, strerror(errno));
+		goto out;
+	}
+
+	if (verbose)
+		printf("ioctl ret=%d, bytes_left=%lu, bytes_missing=%lu, "
+			"cnt=%d, missed=%d\n", ret,
+			(unsigned long)inodes->bytes_left,
+			(unsigned long)inodes->bytes_missing,
+			inodes->elem_cnt, inodes->elem_missed);
+
+	bytes_left = sizeof(full_path);
+	ret = snprintf(full_path, bytes_left, "%s/", argv[optind+1]);
+	path_ptr = full_path + ret;
+	bytes_left -= ret + 1;
+	BUG_ON(bytes_left < 0);
+
+	for (i = 0; i < inodes->elem_cnt; i += 3) {
+		u64 inum = inodes->val[i];
+		u64 offset = inodes->val[i+1];
+		u64 root = inodes->val[i+2];
+		int path_fd;
+		char *name;
+
+		if (getpath) {
+			name = path_for_root(fd, root);
+			if (IS_ERR(name))
+				return PTR_ERR(name);
+			if (!name) {
+				path_ptr[-1] = '\0';
+				path_fd = fd;
+			} else {
+				path_ptr[-1] = '/';
+				ret = snprintf(path_ptr, bytes_left, "%s",
+						name);
+				BUG_ON(ret >= bytes_left);
+				free(name);
+				path_fd = open_file_or_dir(full_path);
+				if (path_fd < 0) {
+					fprintf(stderr, "ERROR: can't access "
+						"'%s'\n", full_path);
+					goto out;
+				}
+			}
+			__ino_to_path_fd(inum, path_fd, verbose, full_path);
+		} else {
+			printf("inode %llu offset %llu root %llu\n", inum,
+				offset, root);
+		}
+	}
+
+out:
+	free(inodes);
+	return ret;
+}
+
+const struct cmd_group inspect_cmd_group = {
+	inspect_cmd_group_usage, NULL, {
+		{ "inode-resolve", cmd_inode_resolve, cmd_inode_resolve_usage,
+			NULL, 0 },
+		{ "logical-resolve", cmd_logical_resolve,
+			cmd_logical_resolve_usage, NULL, 0 },
+		{ 0, 0, 0, 0, 0 }
+	}
+};
+
+int cmd_inspect(int argc, char **argv)
+{
+	return handle_command_group(&inspect_cmd_group, argc, argv);
+}
diff --git a/scrub.c b/cmds-scrub.c
index 9dca5f6..af855ba 100644
--- a/scrub.c
+++ b/cmds-scrub.c
@@ -34,11 +34,15 @@
 
 #include "ctree.h"
 #include "ioctl.h"
-#include "btrfs_cmds.h"
 #include "utils.h"
 #include "volumes.h"
 #include "disk-io.h"
 
+#include "commands.h"
+
+static const char scrub_cmd_group_usage[] =
+	"btrfs scrub <command> [options] <path>|<device>";
+
 #define SCRUB_DATA_FILE "/var/lib/btrfs/scrub.status"
 #define SCRUB_PROGRESS_SOCKET_PATH "/var/lib/btrfs/scrub.progress"
 #define SCRUB_FILE_VERSION_PREFIX "scrub status"
@@ -1047,6 +1051,9 @@ int mkdir_p(char *path)
 	return 0;
 }
 
+static const char * const cmd_scrub_start_usage[];
+static const char * const cmd_scrub_resume_usage[];
+
 static int scrub_start(int argc, char **argv, int resume)
 {
 	int fdmnt;
@@ -1114,21 +1121,16 @@ static int scrub_start(int argc, char **argv, int resume)
 			break;
 		case '?':
 		default:
-			fprintf(stderr, "ERROR: scrub args invalid.\n"
-					" -B  do not background\n"
-					" -d  stats per device (-B only)\n"
-					" -q  quiet\n"
-					" -r  read only mode\n");
-			return 1;
+			usage(resume ? cmd_scrub_resume_usage :
+						cmd_scrub_start_usage);
 		}
 	}
 
 	/* try to catch most error cases before forking */
 
-	if (optind + 1 != argc) {
-		fprintf(stderr, "ERROR: scrub start needs path as last "
-			"argument\n");
-		return 1;
+	if (check_argc_exact(argc - optind, 1)) {
+		usage(resume ? cmd_scrub_resume_usage :
+					cmd_scrub_start_usage);
 	}
 
 	spc.progress = NULL;
@@ -1473,25 +1475,42 @@ out:
 	return 0;
 }
 
-int do_scrub_start(int argc, char **argv)
+static const char * const cmd_scrub_start_usage[] = {
+	"btrfs scrub start [-Bdqr] <path>|<device>",
+	"Start a new scrub",
+	"",
+	"-B     do not background",
+	"-d     stats per device (-B only)",
+	"-q     be quiet",
+	"-r     read only mode",
+	NULL
+};
+
+static int cmd_scrub_start(int argc, char **argv)
 {
 	return scrub_start(argc, argv, 0);
 }
 
-int do_scrub_resume(int argc, char **argv)
-{
-	return scrub_start(argc, argv, 1);
-}
+static const char * const cmd_scrub_cancel_usage[] = {
+	"btrfs scrub cancel <path>|<device>",
+	"Cancel a running scrub",
+	NULL
+};
 
-int do_scrub_cancel(int argc, char **argv)
+static int cmd_scrub_cancel(int argc, char **argv)
 {
-	char *path = argv[1];
+	char *path;
 	int ret;
 	int fdmnt;
 	int err;
 	char mp[BTRFS_PATH_NAME_MAX + 1];
 	struct btrfs_fs_devices *fs_devices_mnt = NULL;
 
+	if (check_argc_exact(argc, 2))
+		usage(cmd_scrub_cancel_usage);
+
+	path = argv[1];
+
 	fdmnt = open_file_or_dir(path);
 	if (fdmnt < 0) {
 		fprintf(stderr, "ERROR: scrub cancel failed\n");
@@ -1528,9 +1547,33 @@ again:
 	return 0;
 }
 
-int do_scrub_status(int argc, char **argv)
+static const char * const cmd_scrub_resume_usage[] = {
+	"btrfs scrub resume [-Bdqr] <path>|<device>",
+	"Resume previously canceled or interrupted scrub",
+	"",
+	"-B     do not background",
+	"-d     stats per device (-B only)",
+	"-q     be quiet",
+	"-r     read only mode",
+	NULL
+};
+
+static int cmd_scrub_resume(int argc, char **argv)
 {
+	return scrub_start(argc, argv, 1);
+}
+
+static const char * const cmd_scrub_status_usage[] = {
+	"btrfs scrub status [-dR] <path>|<device>",
+	"Show status of running or finished scrub",
+	"",
+	"-d     stats per device",
+	"-R     print raw stats",
+	NULL
+};
 
+static int cmd_scrub_status(int argc, char **argv)
+{
 	char *path;
 	struct btrfs_ioctl_fs_info_args fi_args;
 	struct btrfs_ioctl_dev_info_args *di_args = NULL;
@@ -1543,7 +1586,6 @@ int do_scrub_status(int argc, char **argv)
 	int ret;
 	int fdmnt;
 	int i;
-	optind = 1;
 	int print_raw = 0;
 	int do_stats_per_dev = 0;
 	char c;
@@ -1551,6 +1593,7 @@ int do_scrub_status(int argc, char **argv)
 	int fdres = -1;
 	int err = 0;
 
+	optind = 1;
 	while ((c = getopt(argc, argv, "dR")) != -1) {
 		switch (c) {
 		case 'd':
@@ -1561,17 +1604,12 @@ int do_scrub_status(int argc, char **argv)
 			break;
 		case '?':
 		default:
-			fprintf(stderr, "ERROR: scrub status args invalid.\n"
-					" -d  stats per device\n");
-			return 1;
+			usage(cmd_scrub_status_usage);
 		}
 	}
 
-	if (optind + 1 != argc) {
-		fprintf(stderr, "ERROR: scrub status needs path as last "
-			"argument\n");
-		return 1;
-	}
+	if (check_argc_exact(argc - optind, 1))
+		usage(cmd_scrub_status_usage);
 
 	path = argv[optind];
 
@@ -1664,3 +1702,18 @@ out:
 
 	return err;
 }
+
+const struct cmd_group scrub_cmd_group = {
+	scrub_cmd_group_usage, NULL, {
+		{ "start", cmd_scrub_start, cmd_scrub_start_usage, NULL, 0 },
+		{ "cancel", cmd_scrub_cancel, cmd_scrub_cancel_usage, NULL, 0 },
+		{ "resume", cmd_scrub_resume, cmd_scrub_resume_usage, NULL, 0 },
+		{ "status", cmd_scrub_status, cmd_scrub_status_usage, NULL, 0 },
+		{ 0, 0, 0, 0, 0 }
+	}
+};
+
+int cmd_scrub(int argc, char **argv)
+{
+	return handle_command_group(&scrub_cmd_group, argc, argv);
+}
diff --git a/cmds-subvolume.c b/cmds-subvolume.c
new file mode 100644
index 0000000..68ebd40
--- /dev/null
+++ b/cmds-subvolume.c
@@ -0,0 +1,531 @@
+/*
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License v2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this program; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 021110-1307, USA.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/ioctl.h>
+#include <errno.h>
+#include <sys/stat.h>
+#include <libgen.h>
+#include <limits.h>
+
+#include "kerncompat.h"
+#include "ioctl.h"
+
+#include "commands.h"
+
+/* btrfs-list.c */
+int list_subvols(int fd, int print_parent, int get_default);
+int find_updated_files(int fd, u64 root_id, u64 oldest_gen);
+
+static const char subvolume_cmd_group_usage[] =
+	"btrfs subvolume <command> <args>";
+
+/*
+ * test if path is a directory
+ * this function return
+ * 0-> path exists but it is not a directory
+ * 1-> path exists and it is  a directory
+ * -1 -> path is unaccessible
+ */
+static int test_isdir(char *path)
+{
+	struct stat	st;
+	int		res;
+
+	res = stat(path, &st);
+	if(res < 0 )
+		return -1;
+
+	return S_ISDIR(st.st_mode);
+}
+
+static const char * const cmd_subvol_create_usage[] = {
+	"btrfs subvolume create [<dest>/]<name>",
+	"Create a subvolume",
+	"Create a subvolume <name> in <dest>.  If <dest> is not given",
+	"subvolume <name> will be created in the current directory.",
+	NULL
+};
+
+static int cmd_subvol_create(int argc, char **argv)
+{
+	int	res, fddst, len, e;
+	char	*newname;
+	char	*dstdir;
+	struct btrfs_ioctl_vol_args	args;
+	char	*dst;
+
+	if (check_argc_exact(argc, 2))
+		usage(cmd_subvol_create_usage);
+
+	dst = argv[1];
+
+	res = test_isdir(dst);
+	if(res >= 0 ){
+		fprintf(stderr, "ERROR: '%s' exists\n", dst);
+		return 12;
+	}
+
+	newname = strdup(dst);
+	newname = basename(newname);
+	dstdir = strdup(dst);
+	dstdir = dirname(dstdir);
+
+	if( !strcmp(newname,".") || !strcmp(newname,"..") ||
+	     strchr(newname, '/') ){
+		fprintf(stderr, "ERROR: uncorrect subvolume name ('%s')\n",
+			newname);
+		return 14;
+	}
+
+	len = strlen(newname);
+	if (len == 0 || len >= BTRFS_VOL_NAME_MAX) {
+		fprintf(stderr, "ERROR: subvolume name too long ('%s)\n",
+			newname);
+		return 14;
+	}
+
+	fddst = open_file_or_dir(dstdir);
+	if (fddst < 0) {
+		fprintf(stderr, "ERROR: can't access to '%s'\n", dstdir);
+		return 12;
+	}
+
+	printf("Create subvolume '%s/%s'\n", dstdir, newname);
+	strncpy(args.name, newname, BTRFS_PATH_NAME_MAX);
+	res = ioctl(fddst, BTRFS_IOC_SUBVOL_CREATE, &args);
+	e = errno;
+
+	close(fddst);
+
+	if(res < 0 ){
+		fprintf( stderr, "ERROR: cannot create subvolume - %s\n",
+			strerror(e));
+		return 11;
+	}
+
+	return 0;
+}
+
+/*
+ * test if path is a subvolume:
+ * this function return
+ * 0-> path exists but it is not a subvolume
+ * 1-> path exists and it is  a subvolume
+ * -1 -> path is unaccessible
+ */
+static int test_issubvolume(char *path)
+{
+	struct stat	st;
+	int		res;
+
+	res = stat(path, &st);
+	if(res < 0 )
+		return -1;
+
+	return (st.st_ino == 256) && S_ISDIR(st.st_mode);
+}
+
+static const char * const cmd_subvol_delete_usage[] = {
+	"btrfs subvolume delete <name>",
+	"Delete a subvolume",
+	NULL
+};
+
+static int cmd_subvol_delete(int argc, char **argv)
+{
+	int	res, fd, len, e;
+	struct btrfs_ioctl_vol_args	args;
+	char	*dname, *vname, *cpath;
+	char	*path;
+
+	if (check_argc_exact(argc, 2))
+		usage(cmd_subvol_delete_usage);
+
+	path = argv[1];
+
+	res = test_issubvolume(path);
+	if(res<0){
+		fprintf(stderr, "ERROR: error accessing '%s'\n", path);
+		return 12;
+	}
+	if(!res){
+		fprintf(stderr, "ERROR: '%s' is not a subvolume\n", path);
+		return 13;
+	}
+
+	cpath = realpath(path, 0);
+	dname = strdup(cpath);
+	dname = dirname(dname);
+	vname = strdup(cpath);
+	vname = basename(vname);
+	free(cpath);
+
+	if( !strcmp(vname,".") || !strcmp(vname,"..") ||
+	     strchr(vname, '/') ){
+		fprintf(stderr, "ERROR: incorrect subvolume name ('%s')\n",
+			vname);
+		return 14;
+	}
+
+	len = strlen(vname);
+	if (len == 0 || len >= BTRFS_VOL_NAME_MAX) {
+		fprintf(stderr, "ERROR: snapshot name too long ('%s)\n",
+			vname);
+		return 14;
+	}
+
+	fd = open_file_or_dir(dname);
+	if (fd < 0) {
+		close(fd);
+		fprintf(stderr, "ERROR: can't access to '%s'\n", dname);
+		return 12;
+	}
+
+	printf("Delete subvolume '%s/%s'\n", dname, vname);
+	strncpy(args.name, vname, BTRFS_PATH_NAME_MAX);
+	res = ioctl(fd, BTRFS_IOC_SNAP_DESTROY, &args);
+	e = errno;
+
+	close(fd);
+
+	if(res < 0 ){
+		fprintf( stderr, "ERROR: cannot delete '%s/%s' - %s\n",
+			dname, vname, strerror(e));
+		return 11;
+	}
+
+	return 0;
+}
+
+static const char * const cmd_subvol_list_usage[] = {
+	"btrfs subvolume list [-p] <path>",
+	"List subvolumes (and snapshots)",
+	"",
+	"-p     print parent ID",
+	NULL
+};
+
+static int cmd_subvol_list(int argc, char **argv)
+{
+	int fd;
+	int ret;
+	int print_parent = 0;
+	char *subvol;
+
+	optind = 1;
+	while(1) {
+		int c = getopt(argc, argv, "p");
+		if (c < 0)
+			break;
+
+		switch(c) {
+		case 'p':
+			print_parent = 1;
+			break;
+		default:
+			usage(cmd_subvol_list_usage);
+		}
+	}
+
+	if (check_argc_exact(argc - optind, 1))
+		usage(cmd_subvol_list_usage);
+
+	subvol = argv[optind];
+
+	ret = test_issubvolume(subvol);
+	if (ret < 0) {
+		fprintf(stderr, "ERROR: error accessing '%s'\n", subvol);
+		return 12;
+	}
+	if (!ret) {
+		fprintf(stderr, "ERROR: '%s' is not a subvolume\n", subvol);
+		return 13;
+	}
+
+	fd = open_file_or_dir(subvol);
+	if (fd < 0) {
+		fprintf(stderr, "ERROR: can't access '%s'\n", subvol);
+		return 12;
+	}
+	ret = list_subvols(fd, print_parent, 0);
+	if (ret)
+		return 19;
+	return 0;
+}
+
+static const char * const cmd_snapshot_usage[] = {
+	"btrfs subvolume snapshot [-r] <source> [<dest>/]<name>",
+	"Create a snapshot of the subvolume",
+	"Create a writable/readonly snapshot of the subvolume <source> with",
+	"the name <name> in the <dest> directory",
+	"",
+	"-r     create a readonly snapshot",
+	NULL
+};
+
+static int cmd_snapshot(int argc, char **argv)
+{
+	char	*subvol, *dst;
+	int	res, fd, fddst, len, e, readonly = 0;
+	char	*newname;
+	char	*dstdir;
+	struct btrfs_ioctl_vol_args_v2	args;
+
+	memset(&args, 0, sizeof(args));
+
+	optind = 1;
+	while (1) {
+		int c = getopt(argc, argv, "r");
+		if (c < 0)
+			break;
+
+		switch (c) {
+		case 'r':
+			readonly = 1;
+			break;
+		default:
+			usage(cmd_snapshot_usage);
+		}
+	}
+
+	if (check_argc_exact(argc - optind, 2))
+		usage(cmd_snapshot_usage);
+
+	subvol = argv[optind];
+	dst = argv[optind + 1];
+
+	res = test_issubvolume(subvol);
+	if(res<0){
+		fprintf(stderr, "ERROR: error accessing '%s'\n", subvol);
+		return 12;
+	}
+	if(!res){
+		fprintf(stderr, "ERROR: '%s' is not a subvolume\n", subvol);
+		return 13;
+	}
+
+	res = test_isdir(dst);
+	if(res == 0 ){
+		fprintf(stderr, "ERROR: '%s' exists and it is not a directory\n", dst);
+		return 12;
+	}
+
+	if(res>0){
+		newname = strdup(subvol);
+		newname = basename(newname);
+		dstdir = dst;
+	}else{
+		newname = strdup(dst);
+		newname = basename(newname);
+		dstdir = strdup(dst);
+		dstdir = dirname(dstdir);
+	}
+
+	if( !strcmp(newname,".") || !strcmp(newname,"..") ||
+	     strchr(newname, '/') ){
+		fprintf(stderr, "ERROR: incorrect snapshot name ('%s')\n",
+			newname);
+		return 14;
+	}
+
+	len = strlen(newname);
+	if (len == 0 || len >= BTRFS_VOL_NAME_MAX) {
+		fprintf(stderr, "ERROR: snapshot name too long ('%s)\n",
+			newname);
+		return 14;
+	}
+
+	fddst = open_file_or_dir(dstdir);
+	if (fddst < 0) {
+		fprintf(stderr, "ERROR: can't access to '%s'\n", dstdir);
+		return 12;
+	}
+
+	fd = open_file_or_dir(subvol);
+	if (fd < 0) {
+		close(fddst);
+		fprintf(stderr, "ERROR: can't access to '%s'\n", dstdir);
+		return 12;
+	}
+
+	if (readonly) {
+		args.flags |= BTRFS_SUBVOL_RDONLY;
+		printf("Create a readonly snapshot of '%s' in '%s/%s'\n",
+		       subvol, dstdir, newname);
+	} else {
+		printf("Create a snapshot of '%s' in '%s/%s'\n",
+		       subvol, dstdir, newname);
+	}
+
+	args.fd = fd;
+	strncpy(args.name, newname, BTRFS_SUBVOL_NAME_MAX);
+	res = ioctl(fddst, BTRFS_IOC_SNAP_CREATE_V2, &args);
+	e = errno;
+
+	close(fd);
+	close(fddst);
+
+	if(res < 0 ){
+		fprintf( stderr, "ERROR: cannot snapshot '%s' - %s\n",
+			subvol, strerror(e));
+		return 11;
+	}
+
+	return 0;
+}
+
+static const char * const cmd_subvol_get_default_usage[] = {
+	"btrfs subvolume get-dafault <path>",
+	"Get the default subvolume of a filesystem",
+	NULL
+};
+
+static int cmd_subvol_get_default(int argc, char **argv)
+{
+	int fd;
+	int ret;
+	char *subvol;
+
+	if (check_argc_exact(argc, 2))
+		usage(cmd_subvol_get_default_usage);
+
+	subvol = argv[1];
+
+	ret = test_issubvolume(subvol);
+	if (ret < 0) {
+		fprintf(stderr, "ERROR: error accessing '%s'\n", subvol);
+		return 12;
+	}
+	if (!ret) {
+		fprintf(stderr, "ERROR: '%s' is not a subvolume\n", subvol);
+		return 13;
+	}
+
+	fd = open_file_or_dir(subvol);
+	if (fd < 0) {
+		fprintf(stderr, "ERROR: can't access '%s'\n", subvol);
+		return 12;
+	}
+	ret = list_subvols(fd, 0, 1);
+	if (ret)
+		return 19;
+	return 0;
+}
+
+static const char * const cmd_subvol_set_default_usage[] = {
+	"btrfs subvolume set-dafault <subvolid> <path>",
+	"Set the default subvolume of a filesystem",
+	NULL
+};
+
+static int cmd_subvol_set_default(int argc, char **argv)
+{
+	int	ret=0, fd, e;
+	u64	objectid;
+	char	*path;
+	char	*subvolid;
+
+	if (check_argc_exact(argc, 3))
+		usage(cmd_subvol_set_default_usage);
+
+	subvolid = argv[1];
+	path = argv[2];
+
+	fd = open_file_or_dir(path);
+	if (fd < 0) {
+		fprintf(stderr, "ERROR: can't access to '%s'\n", path);
+		return 12;
+	}
+
+	objectid = (unsigned long long)strtoll(subvolid, NULL, 0);
+	if (errno == ERANGE) {
+		fprintf(stderr, "ERROR: invalid tree id (%s)\n",subvolid);
+		return 30;
+	}
+	ret = ioctl(fd, BTRFS_IOC_DEFAULT_SUBVOL, &objectid);
+	e = errno;
+	close(fd);
+	if( ret < 0 ){
+		fprintf(stderr, "ERROR: unable to set a new default subvolume - %s\n",
+			strerror(e));
+		return 30;
+	}
+	return 0;
+}
+
+static const char * const cmd_find_new_usage[] = {
+	"btrfs subvolume find-new <path> <lastgen>",
+	"List the recently modified files in a filesystem",
+	NULL
+};
+
+static int cmd_find_new(int argc, char **argv)
+{
+	int fd;
+	int ret;
+	char *subvol;
+	u64 last_gen;
+
+	if (check_argc_exact(argc, 3))
+		usage(cmd_find_new_usage);
+
+	subvol = argv[1];
+	last_gen = atoll(argv[2]);
+
+	ret = test_issubvolume(subvol);
+	if (ret < 0) {
+		fprintf(stderr, "ERROR: error accessing '%s'\n", subvol);
+		return 12;
+	}
+	if (!ret) {
+		fprintf(stderr, "ERROR: '%s' is not a subvolume\n", subvol);
+		return 13;
+	}
+
+	fd = open_file_or_dir(subvol);
+	if (fd < 0) {
+		fprintf(stderr, "ERROR: can't access '%s'\n", subvol);
+		return 12;
+	}
+	ret = find_updated_files(fd, 0, last_gen);
+	if (ret)
+		return 19;
+	return 0;
+}
+
+const struct cmd_group subvolume_cmd_group = {
+	subvolume_cmd_group_usage, NULL, {
+		{ "create", cmd_subvol_create, cmd_subvol_create_usage, NULL, 0 },
+		{ "delete", cmd_subvol_delete, cmd_subvol_delete_usage, NULL, 0 },
+		{ "list", cmd_subvol_list, cmd_subvol_list_usage, NULL, 0 },
+		{ "snapshot", cmd_snapshot, cmd_snapshot_usage, NULL, 0 },
+		{ "get-default", cmd_subvol_get_default,
+			cmd_subvol_get_default_usage, NULL, 0 },
+		{ "set-default", cmd_subvol_set_default,
+			cmd_subvol_set_default_usage, NULL, 0 },
+		{ "find-new", cmd_find_new, cmd_find_new_usage, NULL, 0 },
+		{ 0, 0, 0, 0, 0 }
+	}
+};
+
+int cmd_subvolume(int argc, char **argv)
+{
+	return handle_command_group(&subvolume_cmd_group, argc, argv);
+}
diff --git a/commands.h b/commands.h
new file mode 100644
index 0000000..5d024c2
--- /dev/null
+++ b/commands.h
@@ -0,0 +1,95 @@
+/*
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License v2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this program; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 021110-1307, USA.
+ */
+
+#define ARGV0_BUF_SIZE	64
+
+struct cmd_struct {
+	const char *token;
+	int (*fn)(int, char **);
+
+	/*
+	 * Usage strings
+	 *
+	 * A NULL-terminated array of the following format:
+	 *
+	 *   usagestr[0] - one-line synopsis (required)
+	 *   usagestr[1] - one-line short description (required)
+	 *   usagestr[2..m] - a long (possibly multi-line) description
+	 *                    (optional)
+	 *   usagestr[m + 1] - an empty line separator (required if at least one
+	 *                     option string is given, not needed otherwise)
+	 *   usagestr[m + 2..n] - option strings, one option per line
+	 *                        (optional)
+	 *   usagestr[n + 1] - NULL terminator
+	 *
+	 * Options (if present) should always (even if there is no long
+	 * description) be prepended with an empty line.  Supplied strings are
+	 * indented but otherwise printed as-is, no automatic wrapping is done.
+	 *
+	 * Grep for cmd_*_usage[] for examples.
+	 */
+	const char * const *usagestr;
+
+	/* should be NULL if token is not a subgroup */
+	const struct cmd_group *next;
+
+	/* if true don't list this token in help listings */
+	int hidden;
+};
+
+struct cmd_group {
+	const char *usagestr;
+	const char *infostr;
+
+	const struct cmd_struct commands[];
+};
+
+/* btrfs.c */
+int prefixcmp(const char *str, const char *prefix);
+
+int check_argc_exact(int nargs, int expected);
+int check_argc_min(int nargs, int expected);
+int check_argc_max(int nargs, int expected);
+
+int handle_command_group(const struct cmd_group *grp, int argc,
+			 char **argv);
+
+/* help.c */
+extern const char * const generic_cmd_help_usage[];
+
+void usage(const char * const *usagestr);
+void usage_command(const struct cmd_struct *cmd, int full, int err);
+void usage_command_group(const struct cmd_group *grp, int all, int err);
+
+void help_unknown_token(const char *arg, const struct cmd_group *grp);
+void help_ambiguous_token(const char *arg, const struct cmd_group *grp);
+
+void help_command_group(const struct cmd_group *grp, int argc, char **argv);
+
+/* common.c */
+int open_file_or_dir(const char *fname);
+
+extern const struct cmd_group subvolume_cmd_group;
+extern const struct cmd_group filesystem_cmd_group;
+extern const struct cmd_group device_cmd_group;
+extern const struct cmd_group scrub_cmd_group;
+extern const struct cmd_group inspect_cmd_group;
+
+int cmd_subvolume(int argc, char **argv);
+int cmd_filesystem(int argc, char **argv);
+int cmd_device(int argc, char **argv);
+int cmd_scrub(int argc, char **argv);
+int cmd_inspect(int argc, char **argv);
diff --git a/common.c b/common.c
new file mode 100644
index 0000000..03f6570
--- /dev/null
+++ b/common.c
@@ -0,0 +1,46 @@
+/*
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License v2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this program; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 021110-1307, USA.
+ */
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <dirent.h>
+#include <fcntl.h>
+
+int open_file_or_dir(const char *fname)
+{
+	int ret;
+	struct stat st;
+	DIR *dirstream;
+	int fd;
+
+	ret = stat(fname, &st);
+	if (ret < 0) {
+		return -1;
+	}
+	if (S_ISDIR(st.st_mode)) {
+		dirstream = opendir(fname);
+		if (!dirstream) {
+			return -2;
+		}
+		fd = dirfd(dirstream);
+	} else {
+		fd = open(fname, O_RDWR);
+	}
+	if (fd < 0) {
+		return -3;
+	}
+	return fd;
+}
diff --git a/help.c b/help.c
new file mode 100644
index 0000000..932bdf2
--- /dev/null
+++ b/help.c
@@ -0,0 +1,207 @@
+/*
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License v2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this program; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 021110-1307, USA.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "commands.h"
+
+extern char argv0_buf[ARGV0_BUF_SIZE];
+
+#define USAGE_SHORT		1U
+#define USAGE_LONG		2U
+#define USAGE_OPTIONS		4U
+#define USAGE_LISTING		8U
+
+static int do_usage_one_command(const char * const *usagestr,
+				unsigned int flags, FILE *outf)
+{
+	int pad = 4;
+
+	if (!usagestr || !*usagestr)
+		return -1;
+
+	fprintf(outf, "%s%s\n", (flags & USAGE_LISTING) ? "    " : "usage: ",
+		*usagestr++);
+
+	/* a short one-line description (mandatory) */
+	if ((flags & USAGE_SHORT) == 0)
+		return 0;
+	else if (!*usagestr)
+		return -2;
+
+	if (flags & USAGE_LISTING)
+		pad = 8;
+	else
+		fputc('\n', outf);
+
+	fprintf(outf, "%*s%s\n", pad, "", *usagestr++);
+
+	/* a long (possibly multi-line) description (optional) */
+	if (!*usagestr || ((flags & USAGE_LONG) == 0))
+		return 0;
+
+	if (**usagestr)
+		fputc('\n', outf);
+	while (*usagestr && **usagestr)
+		fprintf(outf, "%*s%s\n", pad, "", *usagestr++);
+
+	/* options (optional) */
+	if (!*usagestr || ((flags & USAGE_OPTIONS) == 0))
+		return 0;
+
+	/*
+	 * options (if present) should always (even if there is no long
+	 * description) be prepended with an empty line, skip it
+	 */
+	usagestr++;
+
+	fputc('\n', outf);
+	while (*usagestr)
+		fprintf(outf, "%*s%s\n", pad, "", *usagestr++);
+
+	return 0;
+}
+
+static int usage_command_internal(const char * const *usagestr,
+				  const char *token, int full, int lst,
+				  FILE *outf)
+{
+	unsigned int flags = USAGE_SHORT;
+	int ret;
+
+	if (full)
+		flags |= USAGE_LONG | USAGE_OPTIONS;
+	if (lst)
+		flags |= USAGE_LISTING;
+
+	ret = do_usage_one_command(usagestr, flags, outf);
+	switch (ret) {
+	case -1:
+		fprintf(outf, "No usage for '%s'\n", token);
+		break;
+	case -2:
+		fprintf(outf, "No short description for '%s'\n", token);
+		break;
+	}
+
+	return ret;
+}
+
+static void usage_command_usagestr(const char * const *usagestr,
+				   const char *token, int full, int err)
+{
+	FILE *outf = err ? stderr : stdout;
+	int ret;
+
+	ret = usage_command_internal(usagestr, token, full, 0, outf);
+	if (!ret)
+		fputc('\n', outf);
+}
+
+void usage_command(const struct cmd_struct *cmd, int full, int err)
+{
+	usage_command_usagestr(cmd->usagestr, cmd->token, full, err);
+}
+
+void usage(const char * const *usagestr)
+{
+	usage_command_usagestr(usagestr, NULL, 1, 1);
+	exit(129);
+}
+
+static void usage_command_group_internal(const struct cmd_group *grp, int full,
+					 FILE *outf)
+{
+	const struct cmd_struct *cmd = grp->commands;
+	int do_sep = 0;
+
+	for (; cmd->token; cmd++) {
+		if (cmd->hidden)
+			continue;
+
+		if (full && cmd != grp->commands)
+			fputc('\n', outf);
+
+		if (!cmd->next) {
+			if (do_sep) {
+				fputc('\n', outf);
+				do_sep = 0;
+			}
+
+			usage_command_internal(cmd->usagestr, cmd->token, full,
+					       1, outf);
+			continue;
+		}
+
+		/* this is an entry point to a nested command group */
+
+		if (!full && cmd != grp->commands)
+			fputc('\n', outf);
+
+		usage_command_group_internal(cmd->next, full, outf);
+
+		if (!full)
+			do_sep = 1;
+	}
+}
+
+void usage_command_group(const struct cmd_group *grp, int full, int err)
+{
+	FILE *outf = err ? stderr : stdout;
+
+	fprintf(outf, "usage: %s\n\n", grp->usagestr);
+	usage_command_group_internal(grp, full, outf);
+	fputc('\n', outf);
+
+	if (grp->infostr)
+		fprintf(outf, "%s\n", grp->infostr);
+}
+
+void help_unknown_token(const char *arg, const struct cmd_group *grp)
+{
+	fprintf(stderr, "%s: unknown token '%s'\n", argv0_buf, arg);
+	usage_command_group(grp, 0, 1);
+	exit(1);
+}
+
+void help_ambiguous_token(const char *arg, const struct cmd_group *grp)
+{
+	const struct cmd_struct *cmd = grp->commands;
+
+	fprintf(stderr, "%s: ambiguous token '%s'\n", argv0_buf, arg);
+	fprintf(stderr, "\nDid you mean one of these ?\n");
+
+	for (; cmd->token; cmd++) {
+		if (!prefixcmp(cmd->token, arg))
+			fprintf(stderr, "\t%s\n", cmd->token);
+	}
+
+	exit(1);
+}
+
+void help_command_group(const struct cmd_group *grp, int argc, char **argv)
+{
+	int full = 0;
+
+	if (argc > 1) {
+		if (!strcmp(argv[1], "--full"))
+			full = 1;
+	}
+
+	usage_command_group(grp, full, 0);
+}