fs/erofs: add erofs filesystem support

This patch mainly deals with uncompressed files.

Signed-off-by: Huang Jianan <jnhuang95@gmail.com>
diff --git a/include/erofs.h b/include/erofs.h
new file mode 100644
index 0000000..1fbe82b
--- /dev/null
+++ b/include/erofs.h
@@ -0,0 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _EROFS_H_
+#define _EROFS_H_
+
+struct disk_partition;
+
+int erofs_opendir(const char *filename, struct fs_dir_stream **dirsp);
+int erofs_readdir(struct fs_dir_stream *dirs, struct fs_dirent **dentp);
+int erofs_probe(struct blk_desc *fs_dev_desc,
+		struct disk_partition *fs_partition);
+int erofs_read(const char *filename, void *buf, loff_t offset,
+	       loff_t len, loff_t *actread);
+int erofs_size(const char *filename, loff_t *size);
+int erofs_exists(const char *filename);
+void erofs_close(void);
+void erofs_closedir(struct fs_dir_stream *dirs);
+int erofs_uuid(char *uuid_str);
+
+#endif /* _EROFS_H */
diff --git a/include/fs.h b/include/fs.h
index c8df388..b607b00 100644
--- a/include/fs.h
+++ b/include/fs.h
@@ -17,6 +17,7 @@
 #define FS_TYPE_UBIFS	4
 #define FS_TYPE_BTRFS	5
 #define FS_TYPE_SQUASHFS 6
+#define FS_TYPE_EROFS   7
 
 struct blk_desc;