6 files changed, 24 insertions, 19 deletions
diff --git a/extmod/vfs.c b/extmod/vfs.c
index 96d5019b3..77531b874 100644
--- a/extmod/vfs.c
+++ b/extmod/vfs.c
@@ -34,9 +34,6 @@
 
 #if MICROPY_VFS
 
-#if MICROPY_VFS_POSIX
-#include "extmod/vfs_posix.h"
-#endif
 #if MICROPY_VFS_FAT
 #include "extmod/vfs_fat.h"
 #endif
@@ -128,17 +125,11 @@ mp_import_stat_t mp_vfs_import_stat(const char *path) {
         return MP_IMPORT_STAT_NO_EXIST;
     }
 
-    // Fast paths for known VFS types
-    #if MICROPY_VFS_POSIX
-    if (mp_obj_get_type(vfs->obj) == &mp_type_vfs_posix) {
-        return mp_vfs_posix_import_stat(MP_OBJ_TO_PTR(vfs->obj), path_out);
-    }
-    #endif
-    #if MICROPY_VFS_FAT
-    if (mp_obj_get_type(vfs->obj) == &mp_fat_vfs_type) {
-        return fat_vfs_import_stat(MP_OBJ_TO_PTR(vfs->obj), path_out);
+    // If the mounted object has the VFS protocol, call its import_stat helper
+    const mp_vfs_proto_t *proto = mp_obj_get_type(vfs->obj)->protocol;
+    if (proto != NULL) {
+        return proto->import_stat(MP_OBJ_TO_PTR(vfs->obj), path_out);
     }
-    #endif
 
     // delegate to vfs.stat() method
     mp_obj_t path_o = mp_obj_new_str(path_out, strlen(path_out));
diff --git a/extmod/vfs.h b/extmod/vfs.h
index f2efdbe79..730dea043 100644
--- a/extmod/vfs.h
+++ b/extmod/vfs.h
@@ -45,6 +45,11 @@
 #define BP_IOCTL_SEC_COUNT      (4)
 #define BP_IOCTL_SEC_SIZE       (5)
 
+// At the moment the VFS protocol just has import_stat, but could be extended to other methods
+typedef struct _mp_vfs_proto_t {
+    mp_import_stat_t (*import_stat)(void *self, const char *path);
+} mp_vfs_proto_t;
+
 typedef struct _mp_vfs_mount_t {
     const char *str; // mount point with leading /
     size_t len;
diff --git a/extmod/vfs_fat.c b/extmod/vfs_fat.c
index 5666a6b0c..4af836b2d 100644
--- a/extmod/vfs_fat.c
+++ b/extmod/vfs_fat.c
@@ -47,7 +47,8 @@
 
 #define mp_obj_fat_vfs_t fs_user_mount_t
 
-mp_import_stat_t fat_vfs_import_stat(fs_user_mount_t *vfs, const char *path) {
+STATIC mp_import_stat_t fat_vfs_import_stat(void *vfs_in, const char *path) {
+    fs_user_mount_t *vfs = vfs_in;
     FILINFO fno;
     assert(vfs != NULL);
     FRESULT res = f_stat(&vfs->fatfs, path, &fno);
@@ -421,11 +422,17 @@ STATIC const mp_rom_map_elem_t fat_vfs_locals_dict_table[] = {
 };
 STATIC MP_DEFINE_CONST_DICT(fat_vfs_locals_dict, fat_vfs_locals_dict_table);
 
+STATIC const mp_vfs_proto_t fat_vfs_proto = {
+    .import_stat = fat_vfs_import_stat,
+};
+
 const mp_obj_type_t mp_fat_vfs_type = {
     { &mp_type_type },
     .name = MP_QSTR_VfsFat,
     .make_new = fat_vfs_make_new,
+    .protocol = &fat_vfs_proto,
     .locals_dict = (mp_obj_dict_t*)&fat_vfs_locals_dict,
+
 };
 
 #endif // MICROPY_VFS_FAT
diff --git a/extmod/vfs_fat.h b/extmod/vfs_fat.h
index e0836a555..ba2915386 100644
--- a/extmod/vfs_fat.h
+++ b/extmod/vfs_fat.h
@@ -58,7 +58,6 @@ extern const mp_obj_type_t mp_fat_vfs_type;
 extern const mp_obj_type_t mp_type_vfs_fat_fileio;
 extern const mp_obj_type_t mp_type_vfs_fat_textio;
 
-mp_import_stat_t fat_vfs_import_stat(struct _fs_user_mount_t *vfs, const char *path);
 MP_DECLARE_CONST_FUN_OBJ_3(fat_vfs_open_obj);
 
 #endif // MICROPY_INCLUDED_EXTMOD_VFS_FAT_H
diff --git a/extmod/vfs_posix.c b/extmod/vfs_posix.c
index 0db45a0c1..6e3bb2c5b 100644
--- a/extmod/vfs_posix.c
+++ b/extmod/vfs_posix.c
@@ -71,7 +71,8 @@ STATIC mp_obj_t vfs_posix_fun1_helper(mp_obj_t self_in, mp_obj_t path_in, int (*
     return mp_const_none;
 }
 
-mp_import_stat_t mp_vfs_posix_import_stat(mp_obj_vfs_posix_t *self, const char *path) {
+STATIC mp_import_stat_t mp_vfs_posix_import_stat(void *self_in, const char *path) {
+    mp_obj_vfs_posix_t *self = self_in;
     if (self->root_len != 0) {
         self->root.len = self->root_len;
         vstr_add_str(&self->root, path);
@@ -347,10 +348,15 @@ STATIC const mp_rom_map_elem_t vfs_posix_locals_dict_table[] = {
 };
 STATIC MP_DEFINE_CONST_DICT(vfs_posix_locals_dict, vfs_posix_locals_dict_table);
 
+STATIC const mp_vfs_proto_t vfs_posix_proto = {
+    .import_stat = mp_vfs_posix_import_stat,
+};
+
 const mp_obj_type_t mp_type_vfs_posix = {
     { &mp_type_type },
     .name = MP_QSTR_VfsPosix,
     .make_new = vfs_posix_make_new,
+    .protocol = &vfs_posix_proto,
     .locals_dict = (mp_obj_dict_t*)&vfs_posix_locals_dict,
 };
 
diff --git a/extmod/vfs_posix.h b/extmod/vfs_posix.h
index 35a255ff6..00756b4c9 100644
--- a/extmod/vfs_posix.h
+++ b/extmod/vfs_posix.h
@@ -29,13 +29,10 @@
 #include "py/lexer.h"
 #include "py/obj.h"
 
-struct _mp_obj_vfs_posix_t;
-
 extern const mp_obj_type_t mp_type_vfs_posix;
 extern const mp_obj_type_t mp_type_vfs_posix_fileio;
 extern const mp_obj_type_t mp_type_vfs_posix_textio;
 
-mp_import_stat_t mp_vfs_posix_import_stat(struct _mp_obj_vfs_posix_t *self, const char *path_in);
 mp_obj_t mp_vfs_posix_file_open(const mp_obj_type_t *type, mp_obj_t file_in, mp_obj_t mode_in);
 
 #endif // MICROPY_INCLUDED_EXTMOD_VFS_POSIX_H