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

[Gao Xiang]

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

Reviewed-by: Chao Yu <yuch...@huawei.com>
Signed-off-by: Gao Xiang <gaoxian...@huawei.com>
---
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