Add qemu 2.4.0

[kvmfornfv.git] / qemu / roms / ipxe / src / arch / x86_64 / core / linux / linux_syscall.S

diff --git a/qemu/roms/ipxe/src/arch/x86_64/core/linux/linux_syscall.S b/qemu/roms/ipxe/src/arch/x86_64/core/linux/linux_syscall.S
new file mode 100644 (file)
index 0000000..d2805f9
--- /dev/null
+++ b/qemu/roms/ipxe/src/arch/x86_64/core/linux/linux_syscall.S
@@ -0,0 +1,33 @@
+
+       .section ".data"
+       .globl linux_errno
+
+linux_errno:   .int 0
+
+       .section ".text"
+       .code64
+       .globl linux_syscall
+       .type  linux_syscall, @function
+
+linux_syscall:
+       movq    %rdi, %rax    // C arg1 -> syscall number
+       movq    %rsi, %rdi    // C arg2 -> syscall arg1
+       movq    %rdx, %rsi    // C arg3 -> syscall arg2
+       movq    %rcx, %rdx    // C arg4 -> syscall arg3
+       movq    %r8, %r10     // C arg5 -> syscall arg4
+       movq    %r9, %r8      // C arg6 -> syscall arg5
+       movq    8(%rsp), %r9  // C arg7 -> syscall arg6
+
+       syscall
+
+       cmpq    $-4095, %rax
+       jae     1f
+       ret
+
+1:
+       negq    %rax
+       movl    %eax, linux_errno
+       movq    $-1, %rax
+       ret
+
+       .size linux_syscall, . - linux_syscall