[PATCH] erofs: fix ztailpacking for subpage compressed blocks

[Gao Xiang <hsiangkao@linux.alibaba.com>]

`pageofs_in` should be the compressed data offset of the page rather
than of the block.

Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
---
 fs/erofs/zdata.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/erofs/zdata.c b/fs/erofs/zdata.c
index a2c3e87d2f81..8264936b8612 100644
--- a/fs/erofs/zdata.c
+++ b/fs/erofs/zdata.c
@@ -812,7 +812,6 @@ static int z_erofs_register_pcluster(struct z_erofs_decompress_frontend *fe)
 
 	if (ztailpacking) {
 		pcl->obj.index = 0;	/* which indicates ztailpacking */
-		pcl->pageofs_in = erofs_blkoff(fe->inode->i_sb, map->m_pa);
 	} else {
 		pcl->obj.index = erofs_blknr(sb, map->m_pa);
 
@@ -889,6 +888,7 @@ static int z_erofs_pcluster_begin(struct z_erofs_decompress_frontend *fe)
 		}
 		get_page(map->buf.page);
 		WRITE_ONCE(fe->pcl->compressed_bvecs[0].page, map->buf.page);
+		fe->pcl->pageofs_in = map->m_pa & ~PAGE_MASK;
 		fe->mode = Z_EROFS_PCLUSTER_FOLLOWED_NOINPLACE;
 	}
 	/* file-backed inplace I/O pages are traversed in reverse order */
-- 
2.39.3