md-cluster: introduce cluster_check_sync_size
Support resize is a little complex for clustered
raid, since we need to ensure all the nodes share
the same knowledge about the size of raid.
We achieve the goal by check the sync_size which
is in each node's bitmap, we can only change the
capacity after cluster_check_sync_size returns 0.
Also, get_bitmap_from_slot is added to get a slot's
bitmap. And we exported some funcs since they are
used in cluster_check_sync_size().
We can also reuse get_bitmap_from_slot to remove
redundant code existed in bitmap_copy_from_slot.
Reviewed-by: NeilBrown <neilb@suse.com>
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
diff --git a/drivers/md/bitmap.h b/drivers/md/bitmap.h
index 5b6dd63..9f76109 100644
--- a/drivers/md/bitmap.h
+++ b/drivers/md/bitmap.h
@@ -267,8 +267,10 @@ void bitmap_daemon_work(struct mddev *mddev);
int bitmap_resize(struct bitmap *bitmap, sector_t blocks,
int chunksize, int init);
+struct bitmap *get_bitmap_from_slot(struct mddev *mddev, int slot);
int bitmap_copy_from_slot(struct mddev *mddev, int slot,
sector_t *lo, sector_t *hi, bool clear_bits);
+void bitmap_free(struct bitmap *bitmap);
#endif
#endif