user: reorganize the userland sources

1 files changed, 24 insertions, 0 deletions

diff --git a/src/user/lib/syscall.s b/src/user/lib/syscall.s
new file mode 100644
index 0000000..0af49f3
--- /dev/null
+++ b/src/user/lib/syscall.s
@@ -0,0 +1,24 @@
+.section .text
+.global _syscall
+.type _syscall, @function
+_syscall:
+	push %ebx // preserve registers
+	push %esi
+	push %edi
+	push %ebp
+
+	mov 20(%esp), %eax
+	mov 24(%esp), %ebx
+	mov %esp, %ecx
+	mov $_syscall_ret, %edx
+	mov 28(%esp), %esi
+	mov 32(%esp), %edi
+	mov 36(%esp), %ebp
+	sysenter
+
+_syscall_ret:
+	pop %ebp
+	pop %edi
+	pop %esi
+	pop %ebx
+	ret