MISC: add --action option to set or abort check/repair.

Signed-off-by: NeilBrown <neilb@suse.de>

ReadMe.c

@@ -166,6 +166,7 @@ struct option long_options[] = {
     {"no-degraded",0,0,  NoDegraded },
     {"wait",	  0, 0,  WaitOpt},
     {"wait-clean", 0, 0, Waitclean },
+    {"action",    1, 0, Action },
 
     /* For Detail/Examine */
     {"brief",	  0, 0, Brief},
@@ -506,6 +507,7 @@ char Help_misc[] =
 "  --readwrite   -w   : mark array as readwrite\n"
 "  --test        -t   : exit status 0 if ok, 1 if degrade, 2 if dead, 4 if missing\n"
 "  --wait        -W   : wait for resync/rebuild/recovery to finish\n"
+"  --action=          : initiate or abort ('idle' or 'frozen') a 'check' or 'repair'.\n"
 ;
 
 char Help_monitor[] =

mdadm.8.in

@@ -1588,6 +1588,31 @@ successfully waited.  For native arrays this returns immediately as the
 kernel handles dirty-clean transitions at shutdown.  No action is taken
 if safe-mode handling is disabled.
 
+.TP
+.B \-\-action=
+Set the "sync_action" for all md devices given to one of
+.BR idle ,
+.BR frozen ,
+.BR check ,
+.BR repair .
+Setting to
+.B idle
+will abort any currently running action though some actions will
+automatically restart.
+Setting to
+.B frozen
+will abort any current action and ensure no other action starts
+automatically.
+
+Details of
+.B check
+and
+.B repair
+can be found it
+.IR md (4)
+under
+.BR "SCRUBBING AND MISMATCHES" .
+
 .SH For Incremental Assembly mode:
 .TP
 .BR \-\-rebuild\-map ", " \-r

mdadm.c

@@ -230,6 +230,7 @@ int main(int argc, char *argv[])
 		case ExamineBB:
 		case Dump:
 		case Restore:
+		case Action:
 			newmode = MISC;
 			break;
 
@@ -987,6 +988,7 @@ int main(int argc, char *argv[])
 		case O(MISC, UpdateSubarray):
 		case O(MISC, Dump):
 		case O(MISC, Restore):
+		case O(MISC ,Action):
 			if (opt == KillSubarray || opt == UpdateSubarray) {
 				if (c.subarray) {
 					pr_err("subarray can only"
@@ -995,6 +997,21 @@ int main(int argc, char *argv[])
 				}
 				c.subarray = optarg;
 			}
+			if (opt == Action) {
+				if (c.action) {
+					pr_err("Only one --action can be specified\n");
+					exit(2);
+				}
+				if (strcmp(optarg, "idle") == 0 ||
+				    strcmp(optarg, "frozen") == 0 ||
+				    strcmp(optarg, "check") == 0 ||
+				    strcmp(optarg, "repair") == 0)
+					c.action = optarg;
+				else {
+					pr_err("action must be one of idle, frozen, check, repair\n");
+					exit(2);
+				}
+			}
 			if (devmode && devmode != opt &&
 			    (devmode == 'E' || (opt == 'E' && devmode != 'Q'))) {
 				pr_err("--examine/-E cannot be given with ");
@@ -1802,6 +1819,9 @@ static int misc_list(struct mddev_dev *devlist,
 			rv |= Restore_metadata(dv->devname, dump_directory, c, ss,
 					       (dv == devlist && dv->next == NULL));
 			continue;
+		case Action:
+			rv |= SetAction(dv->devname, c->action);
+			continue;
 		}
 		if (dv->devname[0] == '/')
 			mdfd = open_mddev(dv->devname, 1);
@@ -1828,3 +1848,26 @@ static int misc_list(struct mddev_dev *devlist,
 	}
 	return rv;
 }
+
+int SetAction(char *dev, char *action)
+{
+	int fd = open(dev, O_RDONLY);
+	struct mdinfo mdi;
+	if (fd < 0) {
+		pr_err("Couldn't open %s: %s\n", dev, strerror(errno));
+		return 1;
+	}
+	sysfs_init(&mdi, fd, NULL);
+	close(fd);
+	if (!mdi.sys_name[0]) {
+		pr_err("%s is no an md array\n", dev);
+		return 1;
+	}
+
+	if (sysfs_set_str(&mdi, NULL, "sync_action", action) < 0) {
+		pr_err("Count not set action for %s to %s: %s\n",
+		       dev, action, strerror(errno));
+		return 1;
+	}
+	return 0;
+}

mdadm.h

@@ -342,6 +342,7 @@ enum special_options {
 	ExamineBB,
 	Dump,
 	Restore,
+	Action,
 };
 
 enum prefix_standard {
@@ -415,6 +416,7 @@ struct context {
 	int	freeze_reshape;
 	char	*backup_file;
 	int	invalid_backup;
+	char	*action;
 };
 
 struct shape {
@@ -1237,6 +1239,7 @@ extern int Kill_subarray(char *dev, char *subarray, int verbose);
 extern int Update_subarray(char *dev, char *subarray, char *update, struct mddev_ident *ident, int quiet);
 extern int Wait(char *dev);
 extern int WaitClean(char *dev, int sock, int verbose);
+extern int SetAction(char *dev, char *action);
 
 extern int Incremental(struct mddev_dev *devlist, struct context *c,
 		       struct supertype *st);