Assemble: allow an array undergoing reshape to be started without backup file

Though not having the proper backup file can cause data corruption, it
is not enough to justify not being able to start the array at all.
So allow "--invalid-backup" to be specified which says "just continue
even if a backup cannot be restored".

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

1 files changed, 12 insertions, 3 deletions

diff --git a/Assemble.c b/Assemble.c
index dc5ddd5c..ac489e87 100644
--- a/Assemble.c
+++ b/Assemble.c
@@ -133,7 +133,8 @@ static int ident_matches(struct mddev_ident *ident,
 
 int Assemble(struct supertype *st, char *mddev,
 	     struct mddev_ident *ident,
-	     struct mddev_dev *devlist, char *backup_file,
+	     struct mddev_dev *devlist,
+	     char *backup_file, int invalid_backup,
 	     int readonly, int runstop,
 	     char *update, char *homehost, int require_homehost,
 	     int verbose, int force)
@@ -1097,8 +1098,16 @@ int Assemble(struct supertype *st, char *mddev,
 			} else
 				fdlist[i] = -1;
 		}
-		if (!err)
-			err = Grow_restart(st, content, fdlist, bestcnt, backup_file, verbose > 0);
+		if (!err) {
+			err = Grow_restart(st, content, fdlist, bestcnt,
+					   backup_file, verbose > 0);
+			if (err && invalid_backup) {
+				if (verbose > 0)
+					fprintf(stderr, Name ": continuing"
+						" without restoring backup\n");
+				err = 0;
+			}
+		}
 		while (i>0) {
 			i--;
 			if (fdlist[i]>=0) close(fdlist[i]);