util: Introduce md_array_active() helper

Rather than querying md_get_array_info() to determine whether an array
is valid, do the work in md_array_active() using sysfs, and fall back
on md_get_array_info() if sysfs fails.

Signed-off-by: Jes Sorensen <jsorensen@fb.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/mdadm.h b/mdadm.h
index a379973..f6e97fd 100644
--- a/mdadm.h
+++ b/mdadm.h
@@ -1415,6 +1415,7 @@ extern int Dump_metadata(char *dev, char *dir, struct context *c,
 extern int Restore_metadata(char *dev, char *dir, struct context *c,
 			    struct supertype *st, int only);
 
+int md_array_active(int fd);
 int md_get_array_info(int fd, struct mdu_array_info_s *array);
 int md_set_array_info(int fd, struct mdu_array_info_s *array);
 int md_get_disk_info(int fd, struct mdu_disk_info_s *disk);