[PATCH 8/9] erofs-utils: lib: refine z_erofs_get_extent_compressedlen()

[Gao Xiang]

Source kernel commit: 8f9530aeeb4f756bdfa70510b40e5d28ea3c742e
Signed-off-by: Gao Xiang <hsiangkao at linux.alibaba.com>
---
 lib/zmap.c | 30 ++++++++++++------------------
 1 file changed, 12 insertions(+), 18 deletions(-)

diff --git a/lib/zmap.c b/lib/zmap.c
index b2aa483..24bdff7 100644
--- a/lib/zmap.c
+++ b/lib/zmap.c
@@ -320,26 +320,20 @@ static int z_erofs_get_extent_compressedlen(struct z_erofs_maprecorder *m,
 {
 	struct erofs_inode *const vi = m->inode;
 	struct erofs_sb_info *sbi = vi->sbi;
-	struct erofs_map_blocks *const map = m->map;
-	const unsigned int lclusterbits = vi->z_logical_clusterbits;
-	unsigned long lcn;
+	bool bigpcl1 = vi->z_advise & Z_EROFS_ADVISE_BIG_PCLUSTER_1;
+	bool bigpcl2 = vi->z_advise & Z_EROFS_ADVISE_BIG_PCLUSTER_2;
+	unsigned long lcn = m->lcn + 1;
 	int err;
 
-	DBG_BUGON(m->type != Z_EROFS_LCLUSTER_TYPE_PLAIN &&
-		  m->type != Z_EROFS_LCLUSTER_TYPE_HEAD1 &&
-		  m->type != Z_EROFS_LCLUSTER_TYPE_HEAD2);
+	DBG_BUGON(m->type == Z_EROFS_LCLUSTER_TYPE_NONHEAD);
 	DBG_BUGON(m->type != m->headtype);
 
-	if (m->headtype == Z_EROFS_LCLUSTER_TYPE_PLAIN ||
-	    ((m->headtype == Z_EROFS_LCLUSTER_TYPE_HEAD1) &&
-	     !(vi->z_advise & Z_EROFS_ADVISE_BIG_PCLUSTER_1)) ||
-	    ((m->headtype == Z_EROFS_LCLUSTER_TYPE_HEAD2) &&
-	     !(vi->z_advise & Z_EROFS_ADVISE_BIG_PCLUSTER_2))) {
-		map->m_plen = 1 << lclusterbits;
-		return 0;
-	}
+	if ((m->headtype == Z_EROFS_LCLUSTER_TYPE_HEAD1 && !bigpcl1) ||
+	    ((m->headtype == Z_EROFS_LCLUSTER_TYPE_PLAIN ||
+	      m->headtype == Z_EROFS_LCLUSTER_TYPE_HEAD2) && !bigpcl2) ||
+	    (lcn << vi->z_logical_clusterbits) >= vi->i_size)
+		m->compressedblks = 1;
 
-	lcn = m->lcn + 1;
 	if (m->compressedblks)
 		goto out;
 
@@ -364,9 +358,9 @@ static int z_erofs_get_extent_compressedlen(struct z_erofs_maprecorder *m,
 	case Z_EROFS_LCLUSTER_TYPE_HEAD2:
 		/*
 		 * if the 1st NONHEAD lcluster is actually PLAIN or HEAD type
-		 * rather than CBLKCNT, it's a 1 lcluster-sized pcluster.
+		 * rather than CBLKCNT, it's a 1 block-sized pcluster.
 		 */
-		m->compressedblks = 1 << (lclusterbits - sbi->blkszbits);
+		m->compressedblks = 1;
 		break;
 	case Z_EROFS_LCLUSTER_TYPE_NONHEAD:
 		if (m->delta[0] != 1)
@@ -381,7 +375,7 @@ static int z_erofs_get_extent_compressedlen(struct z_erofs_maprecorder *m,
 		return -EFSCORRUPTED;
 	}
 out:
-	map->m_plen = m->compressedblks << sbi->blkszbits;
+	m->map->m_plen = erofs_pos(sbi, m->compressedblks);
 	return 0;
 err_bonus_cblkcnt:
 	erofs_err("bogus CBLKCNT @ lcn %lu of nid %llu",
-- 
2.43.5