sysfs: fixed sysfs_freeze_array array to work properly with Manage_subdevs.

If the array is already frozen when Manage_subdevs is called we don't
want it to unfreeze the array.
This is because Grow calls Manage_subdevs to add devices to an array
being reshaped, and the array must stay frozen over this call.

So if sysfs_freeze_array find the array to be frozen it returns '0',
meaning that it didn't and cannot freeze it.  Then the caller will not
try to unfreeze, which is good.

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

1 files changed, 4 insertions, 3 deletions

diff --git a/sysfs.c b/sysfs.c
index e32ececa..cddabaee 100644
--- a/sysfs.c
+++ b/sysfs.c
@@ -837,7 +837,6 @@ int sysfs_freeze_array(struct mdinfo *sra)
 {
 	/* Try to freeze resync/rebuild on this array/container.
 	 * Return -1 if the array is busy,
-	 * return -2 container cannot be frozen,
 	 * return 0 if this kernel doesn't support 'frozen'
 	 * return 1 if it worked.
 	 */
@@ -847,8 +846,10 @@ int sysfs_freeze_array(struct mdinfo *sra)
 		return 1; /* no sync_action == frozen */
 	if (sysfs_get_str(sra, NULL, "sync_action", buf, 20) <= 0)
 		return 0;
-	if (strcmp(buf, "idle\n") != 0 &&
-	    strcmp(buf, "frozen\n") != 0)
+	if (strcmp(buf, "frozen\n") == 0)
+		/* Already frozen */
+		return 0;
+	if (strcmp(buf, "idle\n") != 0)
 		return -1;
 	if (sysfs_set_str(sra, NULL, "sync_action", "frozen") < 0)
 		return 0;