[PATCH v2 2/3] staging: erofs: differentiate unsupported on-disk format

[Gao Xiang <gaoxiang25@xxxxxxxxxx>]

For some specific fields, use EOPNOTSUPP instead of EIO
for values which look sane but aren't supported right now.

Reviewed-by: Chao Yu <yuchao0@xxxxxxxxxx>
Signed-off-by: Gao Xiang <gaoxiang25@xxxxxxxxxx>
---
change log from v1:
 - use EOPNOTSUPP rather than ENOTSUPP pointed by Chao;

 drivers/staging/erofs/inode.c | 4 ++--
 drivers/staging/erofs/zmap.c  | 6 +++---
 2 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/staging/erofs/inode.c b/drivers/staging/erofs/inode.c
index 461fd4213ce7..c8f3ded17583 100644
--- a/drivers/staging/erofs/inode.c
+++ b/drivers/staging/erofs/inode.c
@@ -24,7 +24,7 @@ static int read_inode(struct inode *inode, void *data)
 		errln("unsupported data mapping %u of nid %llu",
 		      vi->datamode, vi->nid);
 		DBG_BUGON(1);
-		return -EIO;
+		return -EOPNOTSUPP;
 	}
 
 	if (__inode_version(advise) == EROFS_INODE_LAYOUT_V2) {
@@ -95,7 +95,7 @@ static int read_inode(struct inode *inode, void *data)
 		errln("unsupported on-disk inode version %u of nid %llu",
 		      __inode_version(advise), vi->nid);
 		DBG_BUGON(1);
-		return -EIO;
+		return -EOPNOTSUPP;
 	}
 
 	if (!nblks)
diff --git a/drivers/staging/erofs/zmap.c b/drivers/staging/erofs/zmap.c
index 16b3625604f4..5551e615e8ea 100644
--- a/drivers/staging/erofs/zmap.c
+++ b/drivers/staging/erofs/zmap.c
@@ -178,7 +178,7 @@ static int vle_legacy_load_cluster_from_disk(struct z_erofs_maprecorder *m,
 		break;
 	default:
 		DBG_BUGON(1);
-		return -EIO;
+		return -EOPNOTSUPP;
 	}
 	m->type = type;
 	return 0;
@@ -362,7 +362,7 @@ static int vle_extent_lookback(struct z_erofs_maprecorder *m,
 		errln("unknown type %u at lcn %lu of nid %llu",
 		      m->type, lcn, vi->nid);
 		DBG_BUGON(1);
-		return -EIO;
+		return -EOPNOTSUPP;
 	}
 	return 0;
 }
@@ -436,7 +436,7 @@ int z_erofs_map_blocks_iter(struct inode *inode,
 	default:
 		errln("unknown type %u at offset %llu of nid %llu",
 		      m.type, ofs, vi->nid);
-		err = -EIO;
+		err = -EOPNOTSUPP;
 		goto unmap_out;
 	}
 
-- 
2.17.1