1 files changed, 39 insertions, 0 deletions

diff --git a/arch/um/include/sysdep-x86_64/stub.h b/arch/um/include/sysdep-x86_64/stub.h
index 6b5447ad590d..f599058d8263 100644
--- a/arch/um/include/sysdep-x86_64/stub.h
+++ b/arch/um/include/sysdep-x86_64/stub.h
@@ -11,9 +11,48 @@
 #include <sysdep/ptrace_user.h>
 
 extern void stub_segv_handler(int sig);
+extern void stub_clone_handler(void);
 
 #define STUB_SYSCALL_RET PT_INDEX(RAX)
 #define STUB_MMAP_NR __NR_mmap
 #define MMAP_OFFSET(o) (o)
 
+static inline long stub_syscall2(long syscall, long arg1, long arg2)
+{
+        long ret;
+
+        __asm__("movq %0, %%rsi; " : : "g" (arg2) : "%rsi");
+        __asm__("movq %0, %%rdi; " : : "g" (arg1) : "%rdi");
+        __asm__("movq %0, %%rax; " : : "g" (syscall) : "%rax");
+        __asm__("syscall;" : : : "%rax", "%r11", "%rcx");
+        __asm__ __volatile__("movq %%rax, %0; " : "=g" (ret) :);
+        return(ret);
+}
+
+static inline long stub_syscall3(long syscall, long arg1, long arg2, long arg3)
+{
+        __asm__("movq %0, %%rdx; " : : "g" (arg3) : "%rdx");
+        return(stub_syscall2(syscall, arg1, arg2));
+}
+
+static inline long stub_syscall4(long syscall, long arg1, long arg2, long arg3,
+                                 long arg4)
+{
+        __asm__("movq %0, %%r10; " : : "g" (arg4) : "%r10");
+        return(stub_syscall3(syscall, arg1, arg2, arg3));
+}
+
+static inline long stub_syscall6(long syscall, long arg1, long arg2, long arg3,
+                                 long arg4, long arg5, long arg6)
+{
+        __asm__("movq %0, %%r9; " : : "g" (arg6) : "%r9");
+        __asm__("movq %0, %%r8; " : : "g" (arg5) : "%r8");
+        return(stub_syscall4(syscall, arg1, arg2, arg3, arg4));
+}
+
+static inline void trap_myself(void)
+{
+        __asm("int3");
+}
+
 #endif