diff --git a/.vscode/settings.json b/.vscode/settings.json
index 7f2cb407f..d9f4234a0 100755
--- a/.vscode/settings.json
+++ b/.vscode/settings.json
@@ -264,7 +264,8 @@
         "shell_cfg.h": "c",
         "__memory": "c",
         "optional": "c",
-        "system_error": "c"
+        "system_error": "c",
+        "__dirent.h": "c"
     },
     "cortex-debug.showRTOS": false,
     "cortex-debug.variableUseNaturalFormat": false,
diff --git a/mkrtos_knl/knl/globals.c b/mkrtos_knl/knl/globals.c
index 054e40635..614d0d240 100755
--- a/mkrtos_knl/knl/globals.c
+++ b/mkrtos_knl/knl/globals.c
@@ -18,7 +18,7 @@
 #include "mm_man.h"
 #include "ipc.h"
 static mem_t global_mem;                     //!< 全局内存管理块
-static uint8_t mem_block[59 * 1024];        //!< 内核内存分配堆 TODO:自动识别大小，或者从bootstrap中读取
+static uint8_t mem_block[1019 * 1024];        //!< 内核内存分配堆 TODO:自动识别大小，或者从bootstrap中读取
 static kobject_t *kobj_ls[FACTORY_FUNC_MAX]; //!< 全局静态内核对象
 
 void global_reg_kobj(kobject_t *kobj, int inx)
diff --git a/mkrtos_knl/stm32_link.lds b/mkrtos_knl/stm32_link.lds
index b174351dc..2cccee8c4 100644
--- a/mkrtos_knl/stm32_link.lds
+++ b/mkrtos_knl/stm32_link.lds
@@ -1,7 +1,7 @@
 ENTRY(Reset_Handler)
 MEMORY
 {
-  RAM (xrw) : ORIGIN = 0x20000000, LENGTH = 64K
+  RAM (xrw) : ORIGIN = 0x20000000, LENGTH = 1024K
   FLASH (rx) : ORIGIN = 0x8000000 + 0x2000, LENGTH = 64K - 0x2000
 }
 SECTIONS
diff --git a/mkrtos_script/build.sh b/mkrtos_script/build.sh
index 670e2b8ed..f079364a1 100755
--- a/mkrtos_script/build.sh
+++ b/mkrtos_script/build.sh
@@ -9,7 +9,7 @@ export INIT_OFFSET=0x10000
 export BOOTFS_ADDR_OFFSET=0x20000
 export KNL_TEXT=0x8000000
 export KNL_DATA=0x20000000
-export KNL_DATA_SIZE=64K
+export KNL_DATA_SIZE=1024K
 export BOARD=STM32F2x
 export ARCH=cortex-m3
 export PYTHON_EXECUTABLE=python3
diff --git a/mkrtos_user/lib/letter-shell/demo/mkrtos/CMakeLists.txt b/mkrtos_user/lib/letter-shell/demo/mkrtos/CMakeLists.txt
index 613b486a3..73c064a25 100644
--- a/mkrtos_user/lib/letter-shell/demo/mkrtos/CMakeLists.txt
+++ b/mkrtos_user/lib/letter-shell/demo/mkrtos/CMakeLists.txt
@@ -15,7 +15,7 @@ add_library(LetterShell
                ../../src/shell_companion.c
                ../../src/shell_ext.c
                ../../src/shell_cmd_list.c
-               ../../extensions/fs_support/shell_fs.c
+               # ../../extensions/fs_support/shell_fs.c
                ../../extensions/log/log.c
             #    ../../extensions/telnet/telnetd.c
                ../../extensions/shell_enhance/shell_passthrough.c
diff --git a/mkrtos_user/lib/letter-shell/src/shell_cfg.h b/mkrtos_user/lib/letter-shell/src/shell_cfg.h
index 4b927a753..0018dcd3b 100644
--- a/mkrtos_user/lib/letter-shell/src/shell_cfg.h
+++ b/mkrtos_user/lib/letter-shell/src/shell_cfg.h
@@ -39,14 +39,14 @@
  * @brief 是否使用shell伴生对象
  *        一些扩展的组件(文件系统支持，日志工具等)需要使用伴生对象
  */
-#define     SHELL_USING_COMPANION       1
+#define     SHELL_USING_COMPANION       0
 #endif /** SHELL_USING_COMPANION */
 
 #ifndef SHELL_SUPPORT_END_LINE
 /**
  * @brief 支持shell尾行模式
  */
-#define     SHELL_SUPPORT_END_LINE      0
+#define     SHELL_SUPPORT_END_LINE      1
 #endif /** SHELL_SUPPORT_END_LINE */
 
 #ifndef SHELL_HELP_LIST_USER
@@ -107,7 +107,7 @@
  *        启用后，可以通过`exec [addr] [args]`直接执行对应地址的函数
  * @attention 如果地址错误，可能会直接引起程序崩溃
  */
-#define     SHELL_EXEC_UNDEF_FUNC       1
+#define     SHELL_EXEC_UNDEF_FUNC       0
 #endif /** SHELL_EXEC_UNDEF_FUNC */
 
 #ifndef SHELL_PARAMETER_MAX_NUMBER
diff --git a/mkrtos_user/lib/libc_backend/inc/syscall_backend.h b/mkrtos_user/lib/libc_backend/inc/syscall_backend.h
index d75b4d3eb..c3f77bf87 100644
--- a/mkrtos_user/lib/libc_backend/inc/syscall_backend.h
+++ b/mkrtos_user/lib/libc_backend/inc/syscall_backend.h
@@ -4,6 +4,7 @@
 #include "u_types.h"
 #include <sys/uio.h>
 #include <time.h>
+#include <sys/stat.h>
 // #include <unistd.h>
 
 #define ARG_1_BE(ap, arg0, type0)       \
@@ -51,6 +52,9 @@ long syscall_backend(long sys_inx, ...);
 
 void fs_backend_init(void);
 
+long be_lseek(long fd, long offset, long whence);
+int be_open(const char *path, int flags, mode_t mode);
+int be_close(int fd);
 long be_read(long fd, char *buf, long size);
 long be_write(long fd, char *buf, long size);
 long be_readv(long fd, const struct iovec *iov, long iovcnt);
diff --git a/mkrtos_user/lib/libc_backend/src/fs_backend.c b/mkrtos_user/lib/libc_backend/src/fs_backend.c
index 84a676418..19daf06ec 100644
--- a/mkrtos_user/lib/libc_backend/src/fs_backend.c
+++ b/mkrtos_user/lib/libc_backend/src/fs_backend.c
@@ -21,6 +21,47 @@ void fs_backend_init(void)
     assert(fd_map_alloc(0, 1, FD_TTY) >= 0);
     assert(fd_map_alloc(0, 2, FD_TTY) >= 0);
 }
+int be_open(const char *path, int flags, mode_t mode)
+{
+    int fd = fs_open(path, flags, mode);
+
+    if (fd < 0)
+    {
+        return fd;
+    }
+    int user_fd = fd_map_alloc(0, fd, FD_FS);
+
+    if (user_fd < 0)
+    {
+        be_close(user_fd);
+    }
+    return user_fd;
+}
+int be_close(int fd)
+{
+    fd_map_entry_t u_fd;
+    int ret = fd_map_free(fd, &u_fd);
+
+    if (ret < 0)
+    {
+        return -EBADF;
+    }
+    switch (u_fd.type)
+    {
+    case FD_TTY:
+    {
+    }
+    break;
+    case FD_FS:
+    {
+        return fs_close(u_fd.priv_fd);
+    }
+    break;
+    default:
+        return -ENOSYS;
+    }
+    return 0;
+}
 static int be_tty_read(char *buf, long size)
 {
     pid_t pid;
@@ -75,7 +116,7 @@ long be_read(long fd, char *buf, long size)
     break;
     case FD_FS:
     {
-        return fs_read(fd, buf, size);
+        return fs_read(u_fd.priv_fd, buf, size);
     }
     break;
     default:
@@ -113,7 +154,7 @@ long be_write(long fd, char *buf, long size)
     break;
     case FD_FS:
     {
-        return fs_write(fd, buf, size);
+        return fs_write(u_fd.priv_fd, buf, size);
     }
     break;
     default:
@@ -164,7 +205,7 @@ long be_readv(long fd, const struct iovec *iov, long iovcnt)
         break;
         case FD_FS:
         {
-            int rsize = fs_read(fd, iov[i].iov_base, iov[i].iov_len);
+            int rsize = fs_read(u_fd.priv_fd, iov[i].iov_base, iov[i].iov_len);
 
             wlen += rsize;
         }
@@ -207,7 +248,7 @@ long be_writev(long fd, const struct iovec *iov, long iovcnt)
         break;
         case FD_FS:
         {
-            int wsize = fs_write(fd, iov[i].iov_base, iov[i].iov_len);
+            int wsize = fs_write(u_fd.priv_fd, iov[i].iov_base, iov[i].iov_len);
 
             wlen += wsize;
         }
@@ -267,3 +308,28 @@ long sys_be_ioctl(va_list ap)
 #undef ARG2
     return be_ioctl(fd, request, args);
 }
+long be_lseek(long fd, long offset, long whence)
+{
+    fd_map_entry_t u_fd;
+    int ret = fd_map_get(fd, &u_fd);
+
+    if (ret < 0)
+    {
+        return -EBADF;
+    }
+    switch (u_fd.type)
+    {
+    case FD_TTY:
+    {
+    }
+    break;
+    case FD_FS:
+    {
+        return fs_lseek(u_fd.priv_fd, offset, whence);
+    }
+    break;
+    default:
+        return -ENOSYS;
+    }
+    return 0;
+}
\ No newline at end of file
diff --git a/mkrtos_user/lib/mlibc/obj/include/bits/syscall.h b/mkrtos_user/lib/mlibc/obj/include/bits/syscall.h
index e0359b4a0..d97ac48aa 100644
--- a/mkrtos_user/lib/mlibc/obj/include/bits/syscall.h
+++ b/mkrtos_user/lib/mlibc/obj/include/bits/syscall.h
@@ -516,7 +516,7 @@
 #define SYS_personality 136
 #define SYS_setfsuid 138
 #define SYS_setfsgid 139
-#define SYS__llseek 140
+// #define SYS__llseek 140
 #define SYS_getdents 141
 #define SYS__newselect 142
 #define SYS_flock 143
diff --git a/mkrtos_user/lib/mlibc/src/dirent/opendir.c b/mkrtos_user/lib/mlibc/src/dirent/opendir.c
index 5cb84e303..626205245 100644
--- a/mkrtos_user/lib/mlibc/src/dirent/opendir.c
+++ b/mkrtos_user/lib/mlibc/src/dirent/opendir.c
@@ -4,16 +4,22 @@
 #include <stdlib.h>
 #include "__dirent.h"
 #include "syscall.h"
-
+#ifndef NO_LITTLE_MODE
+#include "syscall_backend.h"
+#endif
 DIR *opendir(const char *name)
 {
 	int fd;
 	DIR *dir;
 
-	if ((fd = open(name, O_RDONLY|O_DIRECTORY|O_CLOEXEC)) < 0)
+#ifdef NO_LITTLE_MODE
+	if ((fd = open(name, O_RDONLY | O_DIRECTORY | O_CLOEXEC)) < 0)
+#else
+	if ((fd = be_open(name, O_RDONLY | O_DIRECTORY | O_CLOEXEC, 0)) < 0)
+#endif
 		return 0;
 	if (!(dir = calloc(1, sizeof *dir))) {
-		__syscall(SYS_close, fd);
+		be_close(fd);
 		return 0;
 	}
 	dir->fd = fd;
diff --git a/mkrtos_user/lib/mlibc/src/fcntl/fcntl.c b/mkrtos_user/lib/mlibc/src/fcntl/fcntl.c
index d3bff5c48..705b1fa45 100644
--- a/mkrtos_user/lib/mlibc/src/fcntl/fcntl.c
+++ b/mkrtos_user/lib/mlibc/src/fcntl/fcntl.c
@@ -29,7 +29,7 @@ int fcntl(int fd, int cmd, ...)
 		}
 		ret = __syscall(SYS_fcntl, fd, F_DUPFD_CLOEXEC, 0);
 		if (ret != -EINVAL) {
-			if (ret >= 0) __syscall(SYS_close, ret);
+			if (ret >= 0) be_close(ret);
 			return __syscall_ret(-EINVAL);
 		}
 		ret = __syscall(SYS_fcntl, fd, F_DUPFD, arg);
diff --git a/mkrtos_user/lib/mlibc/src/fcntl/open.c b/mkrtos_user/lib/mlibc/src/fcntl/open.c
index 4c3c82759..f31ee4f24 100644
--- a/mkrtos_user/lib/mlibc/src/fcntl/open.c
+++ b/mkrtos_user/lib/mlibc/src/fcntl/open.c
@@ -1,20 +1,27 @@
 #include <fcntl.h>
 #include <stdarg.h>
 #include "syscall.h"
-
+#ifndef NO_LITTLE_MODE
+#include "syscall_backend.h"
+#endif
 int open(const char *filename, int flags, ...)
 {
 	mode_t mode = 0;
 
-	if ((flags & O_CREAT) || (flags & O_TMPFILE) == O_TMPFILE) {
+	if ((flags & O_CREAT) || (flags & O_TMPFILE) == O_TMPFILE)
+	{
 		va_list ap;
 		va_start(ap, flags);
 		mode = va_arg(ap, mode_t);
 		va_end(ap);
 	}
 
+#ifdef NO_LITTLE_MODE
 	int fd = __sys_open_cp(filename, flags, mode);
-	if (fd>=0 && (flags & O_CLOEXEC))
+#else
+	int fd = be_open(filename, flags, mode);
+#endif
+	if (fd >= 0 && (flags & O_CLOEXEC))
 		__syscall(SYS_fcntl, fd, F_SETFD, FD_CLOEXEC);
 
 	return __syscall_ret(fd);
diff --git a/mkrtos_user/lib/mlibc/src/mq/mq_notify.c b/mkrtos_user/lib/mlibc/src/mq/mq_notify.c
index 0e1e6c7ab..f46a01fbd 100644
--- a/mkrtos_user/lib/mlibc/src/mq/mq_notify.c
+++ b/mkrtos_user/lib/mlibc/src/mq/mq_notify.c
@@ -6,7 +6,9 @@
 #include <unistd.h>
 #include <semaphore.h>
 #include "syscall.h"
-
+#ifndef NO_LITTLE_MODE
+#include "syscall_backend.h"
+#endif
 struct args {
 	sem_t sem;
 	int sock;
@@ -68,7 +70,7 @@ int mq_notify(mqd_t mqd, const struct sigevent *sev)
 	sigfillset(&allmask);
 	pthread_sigmask(SIG_BLOCK, &allmask, &origmask);
 	if (pthread_create(&td, &attr, start, &args)) {
-		__syscall(SYS_close, s);
+		be_close(s);
 		pthread_sigmask(SIG_SETMASK, &origmask, 0);
 		errno = EAGAIN;
 		return -1;
@@ -80,7 +82,7 @@ int mq_notify(mqd_t mqd, const struct sigevent *sev)
 	sem_destroy(&args.sem);
 
 	if (args.err) {
-		__syscall(SYS_close, s);
+		be_close(s);
 		pthread_join(td, 0);
 		pthread_setcancelstate(cs, 0);
 		errno = args.err;
diff --git a/mkrtos_user/lib/mlibc/src/network/if_indextoname.c b/mkrtos_user/lib/mlibc/src/network/if_indextoname.c
index 3b368bf0d..a1c16d5d0 100644
--- a/mkrtos_user/lib/mlibc/src/network/if_indextoname.c
+++ b/mkrtos_user/lib/mlibc/src/network/if_indextoname.c
@@ -5,7 +5,9 @@
 #include <string.h>
 #include <errno.h>
 #include "syscall.h"
-
+#ifndef NO_LITTLE_MODE
+#include "syscall_backend.h"
+#endif
 char *if_indextoname(unsigned index, char *name)
 {
 	struct ifreq ifr;
@@ -14,7 +16,7 @@ char *if_indextoname(unsigned index, char *name)
 	if ((fd = socket(AF_UNIX, SOCK_DGRAM|SOCK_CLOEXEC, 0)) < 0) return 0;
 	ifr.ifr_ifindex = index;
 	r = ioctl(fd, SIOCGIFNAME, &ifr);
-	__syscall(SYS_close, fd);
+	be_close(fd);
 	if (r < 0) {
 		if (errno == ENODEV) errno = ENXIO;
 		return 0;
diff --git a/mkrtos_user/lib/mlibc/src/network/if_nametoindex.c b/mkrtos_user/lib/mlibc/src/network/if_nametoindex.c
index 331413c68..f9cae7aed 100644
--- a/mkrtos_user/lib/mlibc/src/network/if_nametoindex.c
+++ b/mkrtos_user/lib/mlibc/src/network/if_nametoindex.c
@@ -4,7 +4,9 @@
 #include <sys/ioctl.h>
 #include <string.h>
 #include "syscall.h"
-
+#ifndef NO_LITTLE_MODE
+#include "syscall_backend.h"
+#endif
 unsigned if_nametoindex(const char *name)
 {
 	struct ifreq ifr;
@@ -13,6 +15,6 @@ unsigned if_nametoindex(const char *name)
 	if ((fd = socket(AF_UNIX, SOCK_DGRAM|SOCK_CLOEXEC, 0)) < 0) return 0;
 	strncpy(ifr.ifr_name, name, sizeof ifr.ifr_name);
 	r = ioctl(fd, SIOCGIFINDEX, &ifr);
-	__syscall(SYS_close, fd);
+	be_close(fd);
 	return r < 0 ? 0 : ifr.ifr_ifindex;
 }
diff --git a/mkrtos_user/lib/mlibc/src/network/res_msend.c b/mkrtos_user/lib/mlibc/src/network/res_msend.c
index 86c2fcf4f..bd8abf7f4 100644
--- a/mkrtos_user/lib/mlibc/src/network/res_msend.c
+++ b/mkrtos_user/lib/mlibc/src/network/res_msend.c
@@ -14,12 +14,14 @@
 #include "stdio_impl.h"
 #include "syscall.h"
 #include "lookup.h"
-
+#ifndef NO_LITTLE_MODE
+#include "syscall_backend.h"
+#endif
 static void cleanup(void *p)
 {
 	struct pollfd *pfd = p;
 	for (int i=0; pfd[i].fd >= -1; i++)
-		if (pfd[i].fd >= 0) __syscall(SYS_close, pfd[i].fd);
+		if (pfd[i].fd >= 0) be_close(pfd[i].fd);
 }
 
 static unsigned long mtime()
@@ -303,7 +305,7 @@ int __res_msend_rc(int nqueries, const unsigned char *const *queries,
 			 * Immediately close TCP socket so as not to consume
 			 * resources we no longer need. */
 			alens[i] = alen;
-			__syscall(SYS_close, pfd[i].fd);
+			be_close(pfd[i].fd);
 			pfd[i].fd = -1;
 		}
 	}
diff --git a/mkrtos_user/lib/mlibc/src/process/posix_spawn.c b/mkrtos_user/lib/mlibc/src/process/posix_spawn.c
index 8b1fab5b2..0324f2a82 100644
--- a/mkrtos_user/lib/mlibc/src/process/posix_spawn.c
+++ b/mkrtos_user/lib/mlibc/src/process/posix_spawn.c
@@ -110,13 +110,13 @@ static int child(void *args_vp)
 				ret = __syscall(SYS_dup, p);
 				if (ret < 0)
 					goto fail;
-				__syscall(SYS_close, p);
+				be_close(p);
 				p = ret;
 			}
 			switch (op->cmd)
 			{
 			case FDOP_CLOSE:
-				__syscall(SYS_close, op->fd);
+				be_close(op->fd);
 				break;
 			case FDOP_DUP2:
 				fd = op->srcfd;
@@ -147,7 +147,7 @@ static int child(void *args_vp)
 				{
 					if ((ret = __sys_dup2(fd, op->fd)) < 0)
 						goto fail;
-					__syscall(SYS_close, fd);
+					be_close(fd);
 				}
 				break;
 			case FDOP_CHDIR:
diff --git a/mkrtos_user/lib/mlibc/src/stat/fchmodat.c b/mkrtos_user/lib/mlibc/src/stat/fchmodat.c
index bc581050e..996dfc0b2 100644
--- a/mkrtos_user/lib/mlibc/src/stat/fchmodat.c
+++ b/mkrtos_user/lib/mlibc/src/stat/fchmodat.c
@@ -2,7 +2,9 @@
 #include <fcntl.h>
 #include <errno.h>
 #include "syscall.h"
-
+#ifndef NO_LITTLE_MODE
+#include "syscall_backend.h"
+#endif
 int fchmodat(int fd, const char *path, mode_t mode, int flag)
 {
 	if (!flag) return syscall(SYS_fchmodat, fd, path, mode, flag);
@@ -32,6 +34,6 @@ int fchmodat(int fd, const char *path, mode_t mode, int flag)
 		else ret = syscall(SYS_fchmodat, AT_FDCWD, proc, mode);
 	}
 
-	__syscall(SYS_close, fd2);
+	be_close(fd2);
 	return ret;
 }
diff --git a/mkrtos_user/lib/mlibc/src/stdio/fopen.c b/mkrtos_user/lib/mlibc/src/stdio/fopen.c
index 80bc341e6..f026cca6b 100644
--- a/mkrtos_user/lib/mlibc/src/stdio/fopen.c
+++ b/mkrtos_user/lib/mlibc/src/stdio/fopen.c
@@ -2,7 +2,9 @@
 #include <fcntl.h>
 #include <string.h>
 #include <errno.h>
-
+#ifndef NO_LITTLE_MODE
+#include "syscall_backend.h"
+#endif
 FILE *fopen(const char *restrict filename, const char *restrict mode)
 {
 	FILE *f;
@@ -26,6 +28,6 @@ FILE *fopen(const char *restrict filename, const char *restrict mode)
 	f = __fdopen(fd, mode);
 	if (f) return f;
 
-	__syscall(SYS_close, fd);
+	be_close(fd);
 	return 0;
 }
diff --git a/mkrtos_user/lib/mlibc/src/stdio/popen.c b/mkrtos_user/lib/mlibc/src/stdio/popen.c
index 3ec833941..ee68392d1 100644
--- a/mkrtos_user/lib/mlibc/src/stdio/popen.c
+++ b/mkrtos_user/lib/mlibc/src/stdio/popen.c
@@ -5,7 +5,9 @@
 #include <spawn.h>
 #include "stdio_impl.h"
 #include "syscall.h"
-
+#ifndef NO_LITTLE_MODE
+#include "syscall_backend.h"
+#endif
 extern char **__environ;
 
 FILE *popen(const char *cmd, const char *mode)
@@ -27,8 +29,8 @@ FILE *popen(const char *cmd, const char *mode)
 	if (pipe2(p, O_CLOEXEC)) return NULL;
 	f = fdopen(p[op], mode);
 	if (!f) {
-		__syscall(SYS_close, p[0]);
-		__syscall(SYS_close, p[1]);
+		be_close(p[0]);
+		be_close(p[1]);
 		return NULL;
 	}
 
@@ -44,7 +46,7 @@ FILE *popen(const char *cmd, const char *mode)
 				f->pipe_pid = pid;
 				if (!strchr(mode, 'e'))
 					fcntl(p[op], F_SETFD, 0);
-				__syscall(SYS_close, p[1-op]);
+				be_close(p[1-op]);
 				__ofl_unlock();
 				return f;
 			}
@@ -54,7 +56,7 @@ fail:
 		posix_spawn_file_actions_destroy(&fa);
 	}
 	fclose(f);
-	__syscall(SYS_close, p[1-op]);
+	be_close(p[1-op]);
 
 	errno = e;
 	return 0;
diff --git a/mkrtos_user/lib/mlibc/src/stdio/tmpfile.c b/mkrtos_user/lib/mlibc/src/stdio/tmpfile.c
index 2fa8803fc..0d620fca5 100644
--- a/mkrtos_user/lib/mlibc/src/stdio/tmpfile.c
+++ b/mkrtos_user/lib/mlibc/src/stdio/tmpfile.c
@@ -2,7 +2,9 @@
 #include <fcntl.h>
 #include <stdlib.h>
 #include "stdio_impl.h"
-
+#ifndef NO_LITTLE_MODE
+#include "syscall_backend.h"
+#endif
 #define MAXTRIES 100
 
 FILE *tmpfile(void)
@@ -21,7 +23,7 @@ FILE *tmpfile(void)
 			__syscall(SYS_unlinkat, AT_FDCWD, s, 0);
 #endif
 			f = __fdopen(fd, "w+");
-			if (!f) __syscall(SYS_close, fd);
+			if (!f) be_close(fd);
 			return f;
 		}
 	}
diff --git a/mkrtos_user/lib/mlibc/src/time/__map_file.c b/mkrtos_user/lib/mlibc/src/time/__map_file.c
index c2b29fe81..2ff53645d 100644
--- a/mkrtos_user/lib/mlibc/src/time/__map_file.c
+++ b/mkrtos_user/lib/mlibc/src/time/__map_file.c
@@ -2,7 +2,9 @@
 #include <fcntl.h>
 #include <sys/stat.h>
 #include "syscall.h"
-
+#ifndef NO_LITTLE_MODE
+#include "syscall_backend.h"
+#endif
 const char unsigned *__map_file(const char *pathname, size_t *size)
 {
 	struct stat st;
@@ -13,6 +15,6 @@ const char unsigned *__map_file(const char *pathname, size_t *size)
 		map = __mmap(0, st.st_size, PROT_READ, MAP_SHARED, fd, 0);
 		*size = st.st_size;
 	}
-	__syscall(SYS_close, fd);
+	be_close(fd);
 	return map == MAP_FAILED ? 0 : map;
 }
diff --git a/mkrtos_user/lib/mlibc/src/unistd/close.c b/mkrtos_user/lib/mlibc/src/unistd/close.c
index a2105f506..83717d280 100644
--- a/mkrtos_user/lib/mlibc/src/unistd/close.c
+++ b/mkrtos_user/lib/mlibc/src/unistd/close.c
@@ -2,7 +2,9 @@
 #include <errno.h>
 #include "aio_impl.h"
 #include "syscall.h"
-
+#ifndef NO_LITTLE_MODE
+#include "syscall_backend.h"
+#endif
 static int dummy(int fd)
 {
 	return fd;
@@ -13,7 +15,12 @@ weak_alias(dummy, __aio_close);
 int close(int fd)
 {
 	fd = __aio_close(fd);
+#ifdef NO_LITTLE_MODE
 	int r = __syscall_cp(SYS_close, fd);
-	if (r == -EINTR) r = 0;
+#else
+	int r = be_close(fd);
+#endif
+	if (r == -EINTR)
+		r = 0;
 	return __syscall_ret(r);
 }
diff --git a/mkrtos_user/lib/mlibc/src/unistd/faccessat.c b/mkrtos_user/lib/mlibc/src/unistd/faccessat.c
index a6e8b02a5..c3528b8c5 100644
--- a/mkrtos_user/lib/mlibc/src/unistd/faccessat.c
+++ b/mkrtos_user/lib/mlibc/src/unistd/faccessat.c
@@ -64,7 +64,7 @@ int faccessat(int fd, const char *filename, int amode, int flag)
 	__block_all_sigs(&set);
 
 	pid = __clone(checker, stack + sizeof stack, 0, &c);
-	__syscall(SYS_close, p[1]);
+	be_close(p[1]);
 
 #ifdef NO_LITTLE_MODE
 	if (pid < 0 || __syscall(SYS_read, p[0], &ret, sizeof ret) != sizeof(ret))
@@ -73,7 +73,7 @@ int faccessat(int fd, const char *filename, int amode, int flag)
 	if (pid < 0 || be_read(p[0], &ret, sizeof ret) != sizeof(ret))
 		ret = -EBUSY;
 #endif
-	__syscall(SYS_close, p[0]);
+	be_close(p[0]);
 	__syscall(SYS_wait4, pid, &status, __WCLONE, 0);
 
 	__restore_sigs(&set);
diff --git a/mkrtos_user/lib/mlibc/src/unistd/lseek.c b/mkrtos_user/lib/mlibc/src/unistd/lseek.c
index f5b66682a..8c307893a 100644
--- a/mkrtos_user/lib/mlibc/src/unistd/lseek.c
+++ b/mkrtos_user/lib/mlibc/src/unistd/lseek.c
@@ -1,13 +1,19 @@
 #include <unistd.h>
 #include "syscall.h"
-
+#ifndef NO_LITTLE_MODE
+#include "syscall_backend.h"
+#endif
 off_t __lseek(int fd, off_t offset, int whence)
 {
 #ifdef SYS__llseek
 	off_t result;
-	return syscall(SYS__llseek, fd, offset>>32, offset, &result, whence) ? -1 : result;
+	return syscall(SYS__llseek, fd, offset >> 32, offset, &result, whence) ? -1 : result;
 #else
+#ifdef NO_LITTLE_MODE
 	return syscall(SYS_lseek, fd, offset, whence);
+#else
+	return be_lseek(fd, offset, whence);
+#endif
 #endif
 }
 
diff --git a/mkrtos_user/lib/mlibc/src/unistd/write.c b/mkrtos_user/lib/mlibc/src/unistd/write.c
index 8fd5bc5c2..f36a5d44a 100644
--- a/mkrtos_user/lib/mlibc/src/unistd/write.c
+++ b/mkrtos_user/lib/mlibc/src/unistd/write.c
@@ -1,7 +1,14 @@
 #include <unistd.h>
 #include "syscall.h"
 
+#ifndef NO_LITTLE_MODE
+#include "syscall_backend.h"
+#endif
 ssize_t write(int fd, const void *buf, size_t count)
 {
+#ifdef NO_LITTLE_MODE
 	return syscall_cp(SYS_write, fd, buf, count);
+#else
+	return be_write(fd, buf, count);
+#endif
 }
diff --git a/mkrtos_user/lib/sys_svr/inc/cons_cli.h b/mkrtos_user/lib/sys_svr/inc/cons_cli.h
index f50ba9b9c..982fdd138 100644
--- a/mkrtos_user/lib/sys_svr/inc/cons_cli.h
+++ b/mkrtos_user/lib/sys_svr/inc/cons_cli.h
@@ -1,4 +1,5 @@
 #pragma once
+#include <u_types.h>
 #include <string.h>
 int cons_write(const uint8_t *data, int len);
 static inline int cons_write_str(const char *str)
diff --git a/mkrtos_user/lib/sys_util/src/u_app_loader.c b/mkrtos_user/lib/sys_util/src/u_app_loader.c
index 6daab5f1d..22cce18a9 100644
--- a/mkrtos_user/lib/sys_util/src/u_app_loader.c
+++ b/mkrtos_user/lib/sys_util/src/u_app_loader.c
@@ -61,7 +61,7 @@ int app_load(const char *name, uenv_t *cur_env, pid_t *pid)
         printf("app format is error.\n");
         return -1;
     }
-    printf("%s addr is 0x%x\n", name, app);
+    printf("%s addr is [0x%x]\n", name, app);
     umword_t ram_base;
     obj_handler_t hd_task = handler_alloc();
     obj_handler_t hd_thread = handler_alloc();
diff --git a/mkrtos_user/server/CMakeLists.txt b/mkrtos_user/server/CMakeLists.txt
index 15b2d3021..ae9589c4f 100644
--- a/mkrtos_user/server/CMakeLists.txt
+++ b/mkrtos_user/server/CMakeLists.txt
@@ -18,4 +18,4 @@ add_subdirectory(app)
 add_subdirectory(fs)
 add_subdirectory(hello)
 add_subdirectory(drv)
-# add_subdirectory(path_manager)
+add_subdirectory(test)
diff --git a/mkrtos_user/server/fs/fatfs/CMakeLists.txt b/mkrtos_user/server/fs/fatfs/CMakeLists.txt
index 5e8306625..79688cc5f 100644
--- a/mkrtos_user/server/fs/fatfs/CMakeLists.txt
+++ b/mkrtos_user/server/fs/fatfs/CMakeLists.txt
@@ -5,11 +5,12 @@ set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -DUSE_STDPERIPH_DRIVER=1 -DSTM32F10X_XL ")
 file(
     GLOB deps  
     ff15/source/*.c  
-    ext_disk_drv/*.c 
+    # ext_disk_drv/*.c 
+    ram_disk_drv/*.c
     *.c
 )
 
-list(REMOVE_ITEM deps mkrtos_user/server/fs/fatfs/ram_disk_drv/*.*)
+# list(REMOVE_ITEM deps mkrtos_user/server/fs/fatfs/ram_disk_drv/*.*)
 
 add_executable(
     fatfs.elf
diff --git a/mkrtos_user/server/fs/fatfs/fs_rpc.c b/mkrtos_user/server/fs/fatfs/fs_rpc.c
index e6effdc4f..2eda0de3d 100644
--- a/mkrtos_user/server/fs/fatfs/fs_rpc.c
+++ b/mkrtos_user/server/fs/fatfs/fs_rpc.c
@@ -8,11 +8,13 @@
 #include <stdio.h>
 #include <fcntl.h>
 #include <errno.h>
+#include <assert.h>
+#include "rpc_prot.h"
 static fs_t fs;
-
 void fs_svr_init(void)
 {
     fs_init(&fs);
+    meta_reg_svr_obj(&fs.svr, FS_PROT);
 }
 typedef struct file_desc
 {
@@ -140,7 +142,7 @@ int fs_svr_open(const char *path, int flags, int mode)
     else
     {
         file->type = 0;
-        cons_write_str("open file..\n");
+        // cons_write_str("open file..\n");
     }
 
     return fatfs_err_conv(ret);
diff --git a/mkrtos_user/server/fs/fatfs/fs_rpc.h b/mkrtos_user/server/fs/fatfs/fs_rpc.h
index ccebef7a8..ae79b7a30 100644
--- a/mkrtos_user/server/fs/fatfs/fs_rpc.h
+++ b/mkrtos_user/server/fs/fatfs/fs_rpc.h
@@ -1,5 +1,5 @@
 #pragma once
 
-void fs_svr_init(obj_handler_t ipc);
+void fs_svr_init(void);
 void fs_svr_loop(void);
 void *file_temp_buf_get(void);
diff --git a/mkrtos_user/server/fs/fatfs/heap_stack.c b/mkrtos_user/server/fs/fatfs/heap_stack.c
index 700c5a16d..dcc088c04 100644
--- a/mkrtos_user/server/fs/fatfs/heap_stack.c
+++ b/mkrtos_user/server/fs/fatfs/heap_stack.c
@@ -1,5 +1,5 @@
 
-#define HEAP_SIZE 0
+#define HEAP_SIZE 512
 #define STACK_SIZE 1024 * 2
 
 #if defined(__CC_ARM)
diff --git a/mkrtos_user/server/fs/fatfs/main.c b/mkrtos_user/server/fs/fatfs/main.c
index 2855a936e..a387bcf9d 100644
--- a/mkrtos_user/server/fs/fatfs/main.c
+++ b/mkrtos_user/server/fs/fatfs/main.c
@@ -15,12 +15,14 @@ static MKFS_PARM defopt = {FM_ANY, 0, 0, 0};
 
 int main(int args, char *argv[])
 {
-    obj_handler_t ipc_hd;
-    int ret = rpc_creaite_bind_ipc(THREAD_MAIN, NULL, &ipc_hd);
-    assert(ret >= 0);
-    ns_register("/mnt", ipc_hd);
+    obj_handler_t hd;
+    int ret;
+
+    ret = rpc_meta_init(THREAD_MAIN, &hd);
+    assert(ret >= 0);
+    fs_svr_init();
+    ns_register("/mnt", hd);
 
-    fs_svr_init(ipc_hd);
     FRESULT res = f_mount(&fs, "0:", 1);
 
     if (res != FR_OK)
diff --git a/mkrtos_user/server/fs/fatfs/ram_disk_drv/diskio.c b/mkrtos_user/server/fs/fatfs/ram_disk_drv/diskio.c
index 3223c6ab8..ab314f4ae 100644
--- a/mkrtos_user/server/fs/fatfs/ram_disk_drv/diskio.c
+++ b/mkrtos_user/server/fs/fatfs/ram_disk_drv/diskio.c
@@ -9,7 +9,7 @@
 
 #include "ff.h"		/* Obtains integer types */
 #include "diskio.h" /* Declarations of disk functions */
-// #include "ram_disk.h"
+#include "ram_disk.h"
 #include <stdio.h>
 /* Definitions of physical drive number for each drive */
 #define DEV_RAM 0 /* Example: Map Ramdisk to physical drive 0 */
diff --git a/mkrtos_user/server/test/CMakeLists.txt b/mkrtos_user/server/test/CMakeLists.txt
index 642f7d797..2d2580b3e 100644
--- a/mkrtos_user/server/test/CMakeLists.txt
+++ b/mkrtos_user/server/test/CMakeLists.txt
@@ -6,10 +6,10 @@ set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -DUSE_STDPERIPH_DRIVER=1 \
 ")
 
 
-add_executable(shell.elf
+add_executable(test.elf
     ${deps}
 )
-target_link_libraries(shell.elf
+target_link_libraries(test.elf
     PUBLIC
     start
     muslc
@@ -19,7 +19,7 @@ target_link_libraries(shell.elf
     ${GCC_LIB_PATH}/libgcc.a
 )
 target_include_directories(
-    shell.elf
+    test.elf
     PUBLIC
     ${CMAKE_SOURCE_DIR}/mkrtos_user/lib/sys/inc
     ${CMAKE_SOURCE_DIR}/mkrtos_user/lib/sys_util/inc
@@ -33,35 +33,35 @@ target_include_directories(
     ${CMAKE_SOURCE_DIR}/mkrtos_user/lib/mlibc/obj/include
     ${CMAKE_SOURCE_DIR}/mkrtos_user/lib/mlibc/include
 
-    ${CMAKE_SOURCE_DIR}/mkrtos_user/server/shell/bsp/core_inc
-    ${CMAKE_SOURCE_DIR}/mkrtos_user/server/shell/bsp/inc
+    ${CMAKE_SOURCE_DIR}/mkrtos_user/server/test/bsp/core_inc
+    ${CMAKE_SOURCE_DIR}/mkrtos_user/server/test/bsp/inc
 )
-add_dependencies(shell.elf
+add_dependencies(test.elf
 muslc
 )
-set_target_properties(shell.elf PROPERTIES LINK_FLAGS
+set_target_properties(test.elf PROPERTIES LINK_FLAGS
 "-T ${CMAKE_CURRENT_LIST_DIR}/link.lds -pie --gc-section -no-dynamic-linker "
 #--no-warn-rwx-segments
 )
 add_custom_target(
-    shell_dump ALL
+    test_dump ALL
     COMMAND
-    ${CMAKE_OBJDUMP} -s -S shell.elf > ${CMAKE_SOURCE_DIR}/build/output/shell.S
+    ${CMAKE_OBJDUMP} -s -S test.elf > ${CMAKE_SOURCE_DIR}/build/output/test.S
     COMMAND
-    ${CMAKE_READELF} -a shell.elf > ${CMAKE_SOURCE_DIR}/build/output/shell.txt
+    ${CMAKE_READELF} -a test.elf > ${CMAKE_SOURCE_DIR}/build/output/test.txt
     COMMAND
-    ${CMAKE_OBJCOPY} -O binary -S shell.elf shell.bin
+    ${CMAKE_OBJCOPY} -O binary -S test.elf test.bin
     COMMAND
-    ${CMAKE_SIZE} shell.elf
+    ${CMAKE_SIZE} test.elf
     COMMAND
     mkdir -p ${CMAKE_SOURCE_DIR}/build/output/cpio
     COMMAND
-    cp shell.bin ${CMAKE_SOURCE_DIR}/build/output/cpio/shell
+    cp test.bin ${CMAKE_SOURCE_DIR}/build/output/cpio/test
     COMMAND
-    cp shell.elf ${CMAKE_SOURCE_DIR}/build/output/shell.elf
+    cp test.elf ${CMAKE_SOURCE_DIR}/build/output/test.elf
 )
 
-add_dependencies(shell_dump shell.elf)
-add_dependencies(shell_dump sys)
-add_dependencies(shell_dump sys_util)
+add_dependencies(test_dump test.elf)
+add_dependencies(test_dump sys)
+add_dependencies(test_dump sys_util)
  
\ No newline at end of file
diff --git a/mkrtos_user/server/test/src/main.c b/mkrtos_user/server/test/src/main.c
index 8dfe9f296..ee4471bfd 100644
--- a/mkrtos_user/server/test/src/main.c
+++ b/mkrtos_user/server/test/src/main.c
@@ -11,21 +11,19 @@
 #include "u_ns.h"
 #include "test.h"
 #include "u_rpc.h"
+#include "cons_cli.h"
 #include <assert.h>
 #include <stdio.h>
 
 int main(int argc, char *args[])
 {
     printf("argc:%d args[0]:%s\n", argc, args[0]);
-    ulog_write_str(u_get_global_env()->log_hd, "MKRTOS:\n");
 #if 0
     malloc_test();
     rpc_test();
     ns_test();
-#endif
     irq_test();
+#endif
     fs_test();
-    task_unmap(TASK_THIS, vpage_create_raw3(KOBJ_DELETE_RIGHT, 0, TASK_THIS));
-    ulog_write_str(u_get_global_env()->log_hd, "Error.\n");
     return 0;
 }
diff --git a/mkrtos_user/server/test/test/fs_test.c b/mkrtos_user/server/test/test/fs_test.c
index fdcc1e9f4..ffc4e5d7d 100644
--- a/mkrtos_user/server/test/test/fs_test.c
+++ b/mkrtos_user/server/test/test/fs_test.c
@@ -1,21 +1,29 @@
 
 
 #include "fs_cli.h"
+#include "cons_cli.h"
 #include <string.h>
 #include <fcntl.h>
 #include <assert.h>
 #include <stddef.h>
+#include <unistd.h>
+#include <stdio.h>
 void fs_test(void)
 {
-    char tmp[4] = "123";
-    int fd = fs_open("/test", O_CREAT | O_RDWR, 0777);
-    assert(fd >= 0);
-    int wlen = fs_write(fd, tmp, 4);
-    assert(wlen == 4);
-    int ret = fs_lseek(fd, 0, SEEK_SET);
-    assert(ret >= 0);
-    int rlen = fs_read(fd, tmp, 4);
-    assert(rlen == 4);
-    assert(strcmp(tmp, "123") == 0);
-    fs_close(fd);
+    int i = 1000;
+    while (i--)
+    {
+        char tmp[4] = "123";
+        int fd = open("/mnt/1.txt", O_CREAT | O_RDWR, 0777);
+        assert(fd >= 0);
+        int wlen = write(fd, tmp, 4);
+        assert(wlen == 4);
+        int ret = lseek(fd, 0, SEEK_SET);
+        assert(ret >= 0);
+        int rlen = read(fd, tmp, 4);
+        assert(rlen == 4);
+        assert(strcmp(tmp, "123") == 0);
+        close(fd);
+    }
+    printf("%s ok.\n", __func__);
 }
diff --git a/mkrtos_user/server/test/test/irq_test.c b/mkrtos_user/server/test/test/irq_test.c
index 8ee7d9054..9c6186e3c 100644
--- a/mkrtos_user/server/test/test/irq_test.c
+++ b/mkrtos_user/server/test/test/irq_test.c
@@ -33,7 +33,7 @@ void irq_test(void)
     assert(obj != HANDLER_INVALID);
     msg_tag_t tag = factory_create_irq_sender(FACTORY_PROT, vpage_create_raw3(0, 0, obj));
     assert(msg_tag_get_val(tag) >= 0);
-    uirq_bind(obj, TIM2_IRQn, 0);
+    uirq_bind(obj, TIM2_IRQn, u_irq_prio_create(0, 0));
 
     tag = mm_align_alloc(MM_PROT, (void *)0x40000000, 0x50000000 - 0x40000000);
     assert(msg_tag_get_val(tag) >= 0);
diff --git a/mkrtos_user/server/test/test/ns_test.c b/mkrtos_user/server/test/test/ns_test.c
index a832fb229..d9f836232 100644
--- a/mkrtos_user/server/test/test/ns_test.c
+++ b/mkrtos_user/server/test/test/ns_test.c
@@ -14,20 +14,6 @@
 
 void ns_test(void)
 {
-#if 0
-    int ret;
-    obj_handler_t tmp_ipc_hd;
-
-    tmp_ipc_hd = handler_alloc();
-    assert(tmp_ipc_hd != HANDLER_INVALID);
-    msg_tag_t tag = factory_create_ipc(FACTORY_PROT, vpage_create_raw3(0, 0, tmp_ipc_hd));
-    assert(msg_tag_get_val(tag) >= 0);
-    ret = cli_ns_register("shell", tmp_ipc_hd);
-    assert(ret >= 0);
-    ret = cli_ns_query("shell", &tmp_ipc_hd);
-    assert(ret >= 0);
-    ulog_write_str(u_get_global_env()->log_hd, "ns test success.\n");
-#endif
     obj_handler_t tmp_ipc_hd;
 
     tmp_ipc_hd = handler_alloc();
diff --git a/mkrtos_user/server/test/test/rpc_test.c b/mkrtos_user/server/test/test/rpc_test.c
index 10e8f9b2e..492db0d1c 100644
--- a/mkrtos_user/server/test/test/rpc_test.c
+++ b/mkrtos_user/server/test/test/rpc_test.c
@@ -95,7 +95,7 @@ msg_tag_t dispatch_test(msg_tag_t tag, ipc_msg_t *msg)
     tag = test_svr_t_query_dispatch(&test, tag, msg);
 }
 #endif
-RPC_GENERATION_OP2(test_svr_t, 0, query,
+RPC_GENERATION_OP2(test_svr_t, 0, 0, query,
                    rpc_obj_handler_t_t, rpc_obj_handler_t_t, RPC_DIR_OUT, RPC_TYPE_BUF, var0,
                    rpc_obj_handler_t_t, rpc_obj_handler_t_t, RPC_DIR_IN, RPC_TYPE_BUF, var1)
 {
@@ -104,10 +104,10 @@ RPC_GENERATION_OP2(test_svr_t, 0, query,
     return 2;
 }
 
-RPC_GENERATION_DISPATCH2(test_svr_t, 0, query,
+RPC_GENERATION_DISPATCH2(test_svr_t, 0, 0, query,
                          rpc_obj_handler_t_t, rpc_obj_handler_t_t, RPC_DIR_OUT, RPC_TYPE_BUF, var0,
                          rpc_obj_handler_t_t, rpc_obj_handler_t_t, RPC_DIR_IN, RPC_TYPE_BUF, var1)
-RPC_GENERATION_CALL2(test_svr_t, 0, query,
+RPC_GENERATION_CALL2(test_svr_t, 0, 0, query,
                      rpc_obj_handler_t_t, rpc_obj_handler_t_t, RPC_DIR_OUT, RPC_TYPE_BUF, var0,
                      rpc_obj_handler_t_t, rpc_obj_handler_t_t, RPC_DIR_IN, RPC_TYPE_BUF, var1)
 
diff --git a/setting.cmake b/setting.cmake
index 9784c5a54..1df03a5f7 100755
--- a/setting.cmake
+++ b/setting.cmake
@@ -21,7 +21,7 @@ set(CMAKE_SIZE "${CROSS_COMPILE}size" CACHE PATH "" FORCE)
 set(MKRTOS_ARCH $ENV{ARCH})
 
 # -mfloat-abi=soft  -u _printf_float 
-set(CMAKE_C_FLAGS "-mcpu=${MKRTOS_ARCH} -mthumb -Os -g3 -lc -lrdimon -msoft-float -u _printf_float -D=MKRTOS \
+set(CMAKE_C_FLAGS "-mcpu=${MKRTOS_ARCH} -mthumb -O0 -g3 -lc -lrdimon -msoft-float -u _printf_float -D=MKRTOS \
 -std=gnu11 -ffunction-sections -fdata-sections -fno-builtin -mfix-cortex-m3-ldrd \
 -nostartfiles -nodefaultlibs -nostdlib -nostdinc -Xlinker  \
  -fno-stack-protector -Wl,--gc-sections \