Bug fix: umount wasn't detaching loop devices unless mtab support was enabled.
Made some whitespace cleanups while I was there.
diff --git a/util-linux/umount.c b/util-linux/umount.c
index 71ddbd4..7efb636 100644
--- a/util-linux/umount.c
+++ b/util-linux/umount.c
@@ -21,7 +21,7 @@
 #include <getopt.h>
 #include "busybox.h"
 
-#define OPTION_STRING		"flDnrva"
+#define OPTION_STRING		"flDnrvad"
 #define OPT_FORCE			1
 #define OPT_LAZY			2
 #define OPT_DONTFREELOOP	4
@@ -36,7 +36,7 @@
 	char path[2*PATH_MAX];
 	struct mntent me;
 	FILE *fp;
-	int status=EXIT_SUCCESS;
+	int status = EXIT_SUCCESS;
 	unsigned long opt;
 	struct mtab_list {
 		char *dir;
@@ -46,7 +46,7 @@
 
 	/* Parse any options */
 
-	opt = bb_getopt_ulflags (argc, argv, OPTION_STRING);
+	opt = bb_getopt_ulflags(argc, argv, OPTION_STRING);
 
 	argc -= optind;
 	argv += optind;
@@ -59,52 +59,55 @@
 	 * entry.  Notice that this also naturally reverses the list so that -a
 	 * umounts the most recent entries first. */
 
-	m=mtl=0;
-	if(opt & OPT_ALL) {
+	m = mtl = 0;
 
-		/* If we're umounting all, then m points to the start of the list and
-		 * the argument list should be empty (which will match all). */
+	/* If we're umounting all, then m points to the start of the list and
+	 * the argument list should be empty (which will match all). */
 
-		if(!(fp = setmntent(bb_path_mtab_file, "r")))
+	if (!(fp = setmntent(bb_path_mtab_file, "r"))) {
+		if (opt & OPT_ALL)
 			bb_error_msg_and_die("Cannot open %s", bb_path_mtab_file);
-		while (getmntent_r(fp,&me,path,sizeof(path))) {
-			m=xmalloc(sizeof(struct mtab_list));
-			m->next=mtl;
-			m->device=bb_xstrdup(me.mnt_fsname);
-			m->dir=bb_xstrdup(me.mnt_dir);
-			mtl=m;
-		}
-		endmntent(fp);
+	} else while (getmntent_r(fp,&me,path,sizeof(path))) {
+		m = xmalloc(sizeof(struct mtab_list));
+		m->next = mtl;
+		m->device = bb_xstrdup(me.mnt_fsname);
+		m->dir = bb_xstrdup(me.mnt_dir);
+		mtl = m;
+	}
+	endmntent(fp);
 
 	/* If we're not mounting all, we need at least one argument. */
-	} else if(argc <= 0) bb_show_usage();
+	if (!(opt & OPT_ALL)) {
+		m = 0;
+		if (!argc) bb_show_usage();
+	}
+
+
 	
 	// Loop through everything we're supposed to umount, and do so.
-	for(;;) {
+	for (;;) {
 		int curstat;
 
 		// Do we already know what to umount this time through the loop?
-		if(m) safe_strncpy(path,m->dir,PATH_MAX);
+		if (m) safe_strncpy(path, m->dir, PATH_MAX);
 		// For umount -a, end of mtab means time to exit.
-		else if(opt & OPT_ALL) break;
+		else if (opt & OPT_ALL) break;
 		// Get next command line argument (and look it up in mtab list)
-		else if(!argc--) break;
+		else if (!argc--) break;
 		else {
-			// Get next command line argument (and look it up in mtab list)
 			realpath(*argv++, path);
-			if (ENABLE_FEATURE_MTAB_SUPPORT)
-				for(m = mtl; m; m = m->next)
-					if(!strcmp(path, m->dir) || !strcmp(path, m->device))
-						break;
+			for (m = mtl; m; m = m->next)
+				if (!strcmp(path, m->dir) || !strcmp(path, m->device))
+					break;
 		}
 
 		// Let's ask the thing nicely to unmount.
 		curstat = umount(path);
 
 		// Force the unmount, if necessary.
-		if(curstat && doForce) {
+		if (curstat && doForce) {
 			curstat = umount2(path, doForce);
-			if(curstat)
+			if (curstat)
 				bb_error_msg_and_die("forced umount of %s failed!", path);
 		}
 
@@ -117,10 +120,10 @@
 
 		/* De-allocate the loop device.  This ioctl should be ignored on any
 		 * non-loop block devices. */
-		if(ENABLE_FEATURE_MOUNT_LOOP && !(opt & OPT_DONTFREELOOP) && m)
+		if (ENABLE_FEATURE_MOUNT_LOOP && !(opt & OPT_DONTFREELOOP) && m)
 			del_loop(m->device);
 
-		if(curstat) {
+		if (curstat) {
 			/* Yes, the ENABLE is redundant here, but the optimizer for ARM
 			 * can't do simple constant propagation in local variables... */
 			if(ENABLE_FEATURE_MTAB_SUPPORT && !(opt & OPT_NO_MTAB) && m)
@@ -129,16 +132,16 @@
 			bb_perror_msg("Couldn't umount %s", path);
 		}
 		// Find next matching mtab entry for -a or umount /dev
-		while(m && (m = m->next))
-			if((opt & OPT_ALL) || !strcmp(path,m->device))
+		while (m && (m = m->next))
+			if ((opt & OPT_ALL) || !strcmp(path,m->device))
 				break;
 	}
 
 	// Free mtab list if necessary
 
-	if(ENABLE_FEATURE_CLEAN_UP) {
-		while(mtl) {
-			m=mtl->next;
+	if (ENABLE_FEATURE_CLEAN_UP) {
+		while (mtl) {
+			m = mtl->next;
 			free(mtl->device);
 			free(mtl->dir);
 			free(mtl);