diff --git a/sdcard/sdcard.c b/sdcard/sdcard.c
index 45efe36..d8fda67 100644
--- a/sdcard/sdcard.c
+++ b/sdcard/sdcard.c
@@ -1894,6 +1894,105 @@
     exit(1);
 }
 
+static int sdcardfs_setup(const char *source_path, const char *dest_path, uid_t fsuid,
+                        gid_t fsgid, bool multi_user, userid_t userid, gid_t gid, mode_t mask) {
+    char opts[256];
+
+    snprintf(opts, sizeof(opts),
+            "fsuid=%d,fsgid=%d,%smask=%d,userid=%d,gid=%d",
+            fsuid, fsgid, multi_user?"multiuser,":"", mask, userid, gid);
+
+    if (mount(source_path, dest_path, "sdcardfs",
+                        MS_NOSUID | MS_NODEV | MS_NOEXEC | MS_NOATIME, opts) != 0) {
+        ERROR("failed to mount sdcardfs filesystem: %s\n", strerror(errno));
+        return -1;
+    }
+
+    return 0;
+}
+
+static void run_sdcardfs(const char* source_path, const char* label, uid_t uid,
+        gid_t gid, userid_t userid, bool multi_user, bool full_write) {
+    char dest_path_default[PATH_MAX];
+    char dest_path_read[PATH_MAX];
+    char dest_path_write[PATH_MAX];
+    char obb_path[PATH_MAX];
+    snprintf(dest_path_default, PATH_MAX, "/mnt/runtime/default/%s", label);
+    snprintf(dest_path_read, PATH_MAX, "/mnt/runtime/read/%s", label);
+    snprintf(dest_path_write, PATH_MAX, "/mnt/runtime/write/%s", label);
+
+    umask(0);
+    if (multi_user) {
+        /* Multi-user storage is fully isolated per user, so "other"
+         * permissions are completely masked off. */
+        if (sdcardfs_setup(source_path, dest_path_default, uid, gid, multi_user, userid,
+                                                      AID_SDCARD_RW, 0006)
+                || sdcardfs_setup(source_path, dest_path_read, uid, gid, multi_user, userid,
+                                                      AID_EVERYBODY, 0027)
+                || sdcardfs_setup(source_path, dest_path_write, uid, gid, multi_user, userid,
+                                                      AID_EVERYBODY, full_write ? 0007 : 0027)) {
+            ERROR("failed to fuse_setup\n");
+            exit(1);
+        }
+    } else {
+        /* Physical storage is readable by all users on device, but
+         * the Android directories are masked off to a single user
+         * deep inside attr_from_stat(). */
+        if (sdcardfs_setup(source_path, dest_path_default, uid, gid, multi_user, userid,
+                                                      AID_SDCARD_RW, 0006)
+                || sdcardfs_setup(source_path, dest_path_read, uid, gid, multi_user, userid,
+                                                      AID_EVERYBODY, full_write ? 0027 : 0022)
+                || sdcardfs_setup(source_path, dest_path_write, uid, gid, multi_user, userid,
+                                                      AID_EVERYBODY, full_write ? 0007 : 0022)) {
+            ERROR("failed to fuse_setup\n");
+            exit(1);
+        }
+    }
+
+    /* Drop privs */
+    if (setgroups(sizeof(kGroups) / sizeof(kGroups[0]), kGroups) < 0) {
+        ERROR("cannot setgroups: %s\n", strerror(errno));
+        exit(1);
+    }
+    if (setgid(gid) < 0) {
+        ERROR("cannot setgid: %s\n", strerror(errno));
+        exit(1);
+    }
+    if (setuid(uid) < 0) {
+        ERROR("cannot setuid: %s\n", strerror(errno));
+        exit(1);
+    }
+
+    if (multi_user) {
+        snprintf(obb_path, sizeof(obb_path), "%s/obb", source_path);
+        fs_prepare_dir(&obb_path[0], 0775, uid, gid);
+    }
+
+    exit(0);
+}
+
+static bool supports_sdcardfs(void) {
+    FILE *fp;
+    char *buf = NULL;
+    size_t buflen = 0;
+
+    fp = fopen("/proc/filesystems", "r");
+    if (!fp) {
+        ERROR("Could not read /proc/filesystems, error: %s\n", strerror(errno));
+        return false;
+    }
+    while ((getline(&buf, &buflen, fp)) > 0) {
+        if (strstr(buf, "sdcardfs\n")) {
+            free(buf);
+            fclose(fp);
+            return true;
+        }
+    }
+    free(buf);
+    fclose(fp);
+    return false;
+}
+
 int main(int argc, char **argv) {
     const char *source_path = NULL;
     const char *label = NULL;
@@ -1966,6 +2065,10 @@
         sleep(1);
     }
 
-    run(source_path, label, uid, gid, userid, multi_user, full_write);
+    if (supports_sdcardfs()) {
+        run_sdcardfs(source_path, label, uid, gid, userid, multi_user, full_write);
+    } else {
+        run(source_path, label, uid, gid, userid, multi_user, full_write);
+    }
     return 1;
 }