md: merge reconfig and check_reshape methods.

The difference between these two methods is artificial.
Both check that a pending reshape is valid, and perform any
aspect of it that can be done immediately.
'reconfig' handles chunk size and layout.
'check_reshape' handles raid_disks.

So make them just one method.

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

drivers/md/faulty.c

@@ -255,7 +255,7 @@ static void status(struct seq_file *seq, mddev_t *mddev)
 }
 
 
-static int reconfig(mddev_t *mddev)
+static int reshape(mddev_t *mddev)
 {
 	int mode = mddev->new_layout & ModeMask;
 	int count = mddev->new_layout >> ModeShift;
@@ -316,7 +316,7 @@ static int run(mddev_t *mddev)
 	md_set_array_sectors(mddev, faulty_size(mddev, 0, 0));
 	mddev->private = conf;
 
-	reconfig(mddev);
+	reshape(mddev);
 
 	return 0;
 }
@@ -339,7 +339,7 @@ static struct mdk_personality faulty_personality =
 	.run		= run,
 	.stop		= stop,
 	.status		= status,
-	.reconfig	= reconfig,
+	.check_reshape	= reshape,
 	.size		= faulty_size,
 };
 

drivers/md/md.c

@@ -2807,10 +2807,10 @@ layout_store(mddev_t *mddev, const char *buf, size_t len)
 
 	if (mddev->pers) {
 		int err;
-		if (mddev->pers->reconfig == NULL)
+		if (mddev->pers->check_reshape == NULL)
 			return -EBUSY;
 		mddev->new_layout = n;
-		err = mddev->pers->reconfig(mddev);
+		err = mddev->pers->check_reshape(mddev);
 		if (err) {
 			mddev->new_layout = mddev->layout;
 			return err;
@@ -2885,10 +2885,10 @@ chunk_size_store(mddev_t *mddev, const char *buf, size_t len)
 
 	if (mddev->pers) {
 		int err;
-		if (mddev->pers->reconfig == NULL)
+		if (mddev->pers->check_reshape == NULL)
 			return -EBUSY;
 		mddev->new_chunk_sectors = n >> 9;
-		err = mddev->pers->reconfig(mddev);
+		err = mddev->pers->check_reshape(mddev);
 		if (err) {
 			mddev->new_chunk_sectors = mddev->chunk_sectors;
 			return err;
@@ -5224,11 +5224,11 @@ static int update_array_info(mddev_t *mddev, mdu_array_info_t *info)
 		 * we don't need to do anything at the md level, the
 		 * personality will take care of it all.
 		 */
-		if (mddev->pers->reconfig == NULL)
+		if (mddev->pers->check_reshape == NULL)
 			return -EINVAL;
 		else {
 			mddev->new_layout = info->layout;
-			rv = mddev->pers->reconfig(mddev);
+			rv = mddev->pers->check_reshape(mddev);
 			if (rv)
 				mddev->new_layout = mddev->layout;
 			return rv;
@@ -6731,7 +6731,8 @@ void md_check_recovery(mddev_t *mddev)
 		 */
 
 		if (mddev->reshape_position != MaxSector) {
-			if (mddev->pers->check_reshape(mddev) != 0)
+			if (mddev->pers->check_reshape == NULL ||
+			    mddev->pers->check_reshape(mddev) != 0)
 				/* Cannot proceed */
 				goto unlock;
 			set_bit(MD_RECOVERY_RESHAPE, &mddev->recovery);

drivers/md/md.h

@@ -326,7 +326,6 @@ struct mdk_personality
 	int (*check_reshape) (mddev_t *mddev);
 	int (*start_reshape) (mddev_t *mddev);
 	void (*finish_reshape) (mddev_t *mddev);
-	int (*reconfig) (mddev_t *mddev);
 	/* quiesce moves between quiescence states
 	 * 0 - fully active
 	 * 1 - no new requests allowed

drivers/md/raid5.c

@@ -4868,14 +4868,14 @@ static int check_stripe_cache(mddev_t *mddev)
 	return 1;
 }
 
-static int raid5_check_reshape(mddev_t *mddev)
+static int check_reshape(mddev_t *mddev)
 {
 	raid5_conf_t *conf = mddev->private;
 
 	if (mddev->delta_disks == 0 &&
 	    mddev->new_layout == mddev->layout &&
 	    mddev->new_chunk_sectors == mddev->chunk_sectors)
-		return -EINVAL; /* nothing to do */
+		return 0; /* nothing to do */
 	if (mddev->bitmap)
 		/* Cannot grow a bitmap yet */
 		return -EBUSY;
@@ -5165,7 +5165,7 @@ static void *raid5_takeover_raid6(mddev_t *mddev)
 }
 
 
-static int raid5_reconfig(mddev_t *mddev)
+static int raid5_check_reshape(mddev_t *mddev)
 {
 	/* For a 2-drive array, the layout and chunk size can be changed
 	 * immediately as not restriping is needed.
@@ -5202,12 +5202,13 @@ static int raid5_reconfig(mddev_t *mddev)
 		set_bit(MD_CHANGE_DEVS, &mddev->flags);
 		md_wakeup_thread(mddev->thread);
 	}
-	return 0;
+	return check_reshape(mddev);
 }
 
-static int raid6_reconfig(mddev_t *mddev)
+static int raid6_check_reshape(mddev_t *mddev)
 {
 	int new_chunk = mddev->new_chunk_sectors;
+
 	if (mddev->new_layout >= 0 && !algorithm_valid_raid6(mddev->new_layout))
 		return -EINVAL;
 	if (new_chunk > 0) {
@@ -5221,7 +5222,7 @@ static int raid6_reconfig(mddev_t *mddev)
 	}
 
 	/* They look valid */
-	return 0;
+	return check_reshape(mddev);
 }
 
 static void *raid5_takeover(mddev_t *mddev)
@@ -5312,12 +5313,11 @@ static struct mdk_personality raid6_personality =
 	.sync_request	= sync_request,
 	.resize		= raid5_resize,
 	.size		= raid5_size,
-	.check_reshape	= raid5_check_reshape,
+	.check_reshape	= raid6_check_reshape,
 	.start_reshape  = raid5_start_reshape,
 	.finish_reshape = raid5_finish_reshape,
 	.quiesce	= raid5_quiesce,
 	.takeover	= raid6_takeover,
-	.reconfig	= raid6_reconfig,
 };
 static struct mdk_personality raid5_personality =
 {
@@ -5340,7 +5340,6 @@ static struct mdk_personality raid5_personality =
 	.finish_reshape = raid5_finish_reshape,
 	.quiesce	= raid5_quiesce,
 	.takeover	= raid5_takeover,
-	.reconfig	= raid5_reconfig,
 };
 
 static struct mdk_personality raid4_personality =