diff options
Diffstat (limited to '')
| -rw-r--r-- | fs/overlayfs/util.c | 17 |
1 files changed, 14 insertions, 3 deletions
diff --git a/fs/overlayfs/util.c b/fs/overlayfs/util.c index 9dfec74ec77d..6f1078028c66 100644 --- a/fs/overlayfs/util.c +++ b/fs/overlayfs/util.c @@ -55,10 +55,21 @@ struct super_block *ovl_same_sb(struct super_block *sb) return NULL; } -bool ovl_can_decode_fh(struct super_block *sb) +/* + * Check if underlying fs supports file handles and try to determine encoding + * type, in order to deduce maximum inode number used by fs. + * + * Return 0 if file handles are not supported. + * Return 1 (FILEID_INO32_GEN) if fs uses the default 32bit inode encoding. + * Return -1 if fs uses a non default encoding with unknown inode size. + */ +int ovl_can_decode_fh(struct super_block *sb) { - return (sb->s_export_op && sb->s_export_op->fh_to_dentry && - !uuid_is_null(&sb->s_uuid)); + if (!sb->s_export_op || !sb->s_export_op->fh_to_dentry || + uuid_is_null(&sb->s_uuid)) + return 0; + + return sb->s_export_op->encode_fh ? -1 : FILEID_INO32_GEN; } struct dentry *ovl_indexdir(struct super_block *sb) |