ntfs: account for direct MFT bitmap cluster allocation

The MFT bitmap extension fast path sets $Bitmap directly, bypassing
ntfs_cluster_alloc() and its free_clusters and lcn_empty_bits_per_page
updates. Successful extensions overreport free space, and rollback adds
back counts that were never deducted.

Update both counts under lcnbmp_lock and the bitmap folio lock. Require
a nonzero page count and space remaining after delayed-allocation
reservations; otherwise use the regular allocator. The page check also
prevents underflow when the initial scan recorded zero after a read error.

Fixes: 6251f0b0de7d ("ntfs: update super block operations")
Suggested-by: Baolin Liu <liubaolin@kylinos.cn>
Reviewed-by: Baolin Liu <liubaolin@kylinos.cn>
Signed-off-by: Xuewen Wang <wangxuewen@kylinos.cn>
Reviewed-by: Baolin Liu <liubaolin@kylinos.cn>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>

0 files changed, 0 insertions, 0 deletions