[PATCH AUTOSEL 6.7 13/19] erofs: fix ztailpacking for subpage compressed blocks

[Sasha Levin]

From: Gao Xiang <hsiangkao@xxxxxxxxxxxxxxxxx>

[ Upstream commit e5aba911dee5e20fa82efbe13e0af8f38ea459e7 ]

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

Acked-by: Chao Yu <chao@xxxxxxxxxx>
Reviewed-by: Yue Hu <huyue2@xxxxxxxxxxx>
Signed-off-by: Gao Xiang <hsiangkao@xxxxxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20231214161337.753049-1-hsiangkao@xxxxxxxxxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 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 a7e6847f6f8f..c9ae96467d98 100644
--- a/fs/erofs/zdata.c
+++ b/fs/erofs/zdata.c
@@ -815,7 +815,6 @@ 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);
 		pcl->tailpacking_size = map->m_plen;
 	} else {
 		pcl->obj.index = map->m_pa >> PAGE_SHIFT;
@@ -893,6 +892,7 @@ 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 */
-- 
2.43.0