Merge tag 'md-6.9-20240301' of https://git.kernel.org/pub/scm/linux/kernel/git/song/md into for-6.9/block

Pull MD updates from Song:

"The major changes are:

 1. Refactor raid1 read_balance, by Yu Kuai and Paul Luse.
 2. Clean up and fix for md_ioctl, by Li Nan.
 3. Other small fixes, by Gui-Dong Han and Heming Zhao."

* tag 'md-6.9-20240301' of https://git.kernel.org/pub/scm/linux/kernel/git/song/md: (22 commits)
  md/raid1: factor out helpers to choose the best rdev from read_balance()
  md/raid1: factor out the code to manage sequential IO
  md/raid1: factor out choose_bb_rdev() from read_balance()
  md/raid1: factor out choose_slow_rdev() from read_balance()
  md/raid1: factor out read_first_rdev() from read_balance()
  md/raid1-10: factor out a new helper raid1_should_read_first()
  md/raid1-10: add a helper raid1_check_read_range()
  md/raid1: fix choose next idle in read_balance()
  md/raid1: record nonrot rdevs while adding/removing rdevs to conf
  md/raid1: factor out helpers to add rdev to conf
  md: add a new helper rdev_has_badblock()
  md/raid5: fix atomicity violation in raid5_cache_count
  md/md-bitmap: fix incorrect usage for sb_index
  md: check mddev->pers before calling md_set_readonly()
  md: clean up openers check in do_md_stop() and md_set_readonly()
  md: sync blockdev before stopping raid or setting readonly
  md: factor out a helper to sync mddev
  md: Don't clear MD_CLOSING when the raid is about to stop
  md: return directly before setting did_set_md_closing
  md: clean up invalid BUG_ON in md_ioctl
  ...

Author: axboe

drivers/md/md-bitmap.c

@@ -234,7 +234,8 @@ static int __write_sb_page(struct md_rdev *rdev, struct bitmap *bitmap,
 	sector_t doff;
 
 	bdev = (rdev->meta_bdev) ? rdev->meta_bdev : rdev->bdev;
-	if (pg_index == store->file_pages - 1) {
+	/* we compare length (page numbers), not page offset. */
+	if ((pg_index - store->sb_index) == store->file_pages - 1) {
 		unsigned int last_page_size = store->bytes & (PAGE_SIZE - 1);
 
 		if (last_page_size == 0)
@@ -438,8 +439,8 @@ static void filemap_write_page(struct bitmap *bitmap, unsigned long pg_index,
 	struct page *page = store->filemap[pg_index];
 
 	if (mddev_is_clustered(bitmap->mddev)) {
-		pg_index += bitmap->cluster_slot *
-			DIV_ROUND_UP(store->bytes, PAGE_SIZE);
+		/* go to node bitmap area starting point */
+		pg_index += store->sb_index;
 	}
 
 	if (store->file)
@@ -952,6 +953,7 @@ static void md_bitmap_file_set_bit(struct bitmap *bitmap, sector_t block)
 	unsigned long index = file_page_index(store, chunk);
 	unsigned long node_offset = 0;
 
+	index += store->sb_index;
 	if (mddev_is_clustered(bitmap->mddev))
 		node_offset = bitmap->cluster_slot * store->file_pages;
 
@@ -982,6 +984,7 @@ static void md_bitmap_file_clear_bit(struct bitmap *bitmap, sector_t block)
 	unsigned long index = file_page_index(store, chunk);
 	unsigned long node_offset = 0;
 
+	index += store->sb_index;
 	if (mddev_is_clustered(bitmap->mddev))
 		node_offset = bitmap->cluster_slot * store->file_pages;