xnu-3248.60.10.tar.gz

[apple/xnu.git] / libsyscall / custom / custom.s

diff --git a/libsyscall/custom/custom.s b/libsyscall/custom/custom.s
index a6a4f8bb8cd36cadbabf4b434ddc377085b7b5fb..b76b96fe7dcbb8ac75c967797e26031fb135e669 100644 (file)
--- a/libsyscall/custom/custom.s
+++ b/libsyscall/custom/custom.s
@@ -32,24 +32,29 @@
 
 #if defined(__i386__)
 
 
 #if defined(__i386__)
 

-       .globl  _errno
+/*
+ * i386 needs custom assembly to transform the return from syscalls
+ * into a proper stack for a function call out to cerror{,_nocancel}.
+ */
+
+LABEL(tramp_cerror)
+       mov             %esp, %edx
+       andl    $0xfffffff0, %esp
+       subl    $16, %esp
+       movl    %edx, 4(%esp)
+       movl    %eax, (%esp)
+       CALL_EXTERN(_cerror)
+       movl    4(%esp), %esp
+       ret

 
 

-LABEL(cerror)
-       movl    $0,%ecx
-       jmp             1f
-LABEL(cerror_nocancel)
-       movl    $1,%ecx
-1:     REG_TO_EXTERN(%eax, _errno)
-       mov             %esp,%edx
-       andl    $0xfffffff0,%esp
-       subl    $16,%esp
-       movl    %edx,8(%esp)
-       movl    %ecx,4(%esp)
-       movl    %eax,(%esp)
-       CALL_EXTERN(_cthread_set_errno_self)
-       movl    8(%esp),%esp
-       movl    $-1,%eax
-       movl    $-1,%edx /* in case a 64-bit value is returned */
+LABEL(tramp_cerror_nocancel)
+       mov             %esp, %edx
+       andl    $0xfffffff0, %esp
+       subl    $16, %esp
+       movl    %edx, 4(%esp)
+       movl    %eax, (%esp)
+       CALL_EXTERN(_cerror_nocancel)
+       movl    4(%esp), %esp

        ret
 
 LABEL(__sysenter_trap)
        ret
 
 LABEL(__sysenter_trap)


@@ -57,45 +62,35 @@ LABEL(__sysenter_trap)
        movl %esp, %ecx
        sysenter
 
        movl %esp, %ecx
        sysenter
 

-#elif defined(__x86_64__)
-
-       .globl  _errno
+       .globl _i386_get_ldt
+       ALIGN
+_i386_get_ldt:
+       movl    $6,%eax
+       MACHDEP_SYSCALL_TRAP
+       jnb             2f
+       jmp             tramp_cerror
+2:     ret

 
 

-LABEL(cerror)
-       /* cancelable syscall, for arg1 to _cthread_set_errno_self */
-       movq    $0,%rsi
-       jmp             1f
-LABEL(cerror_nocancel)
-       /* non-cancelable, see above. */
-       movq    $1,%rsi
-1:     PICIFY(_errno) /* address -> %r11 */
-       movl    %eax,(%r11)
-       mov     %rsp,%rdx
-       andq    $-16,%rsp
-       subq    $16,%rsp
-       // Preserve the original stack
-       movq    %rdx,(%rsp)
-       movq    %rax,%rdi
-       CALL_EXTERN(_cthread_set_errno_self)
-       // Restore the original stack
-       movq    (%rsp),%rsp
-       movq    $-1,%rax
-       movq    $-1,%rdx /* in case a 128-bit value is returned */
-       ret

 
 

-#else
-#error Unsupported architecture
-#endif
+       .globl _i386_set_ldt
+       ALIGN
+_i386_set_ldt:
+       movl    $5,%eax
+       MACHDEP_SYSCALL_TRAP
+       jnb             2f
+       jmp             tramp_cerror
+2:     ret

 
 

-#if defined(__i386__) || defined(__x86_64__)
+#elif defined(__x86_64__)

 
        .globl _i386_get_ldt
        ALIGN
 _i386_get_ldt:
        movl    $6,%eax
        MACHDEP_SYSCALL_TRAP
 
        .globl _i386_get_ldt
        ALIGN
 _i386_get_ldt:
        movl    $6,%eax
        MACHDEP_SYSCALL_TRAP

-       jnb     2f
-       jmp     cerror
+       jnb             2f
+       movq    %rax, %rdi
+       jmp             _cerror

 2:     ret
 
 
 2:     ret
 
 


@@ -104,8 +99,9 @@ _i386_get_ldt:
 _i386_set_ldt:
        movl    $5,%eax
        MACHDEP_SYSCALL_TRAP
 _i386_set_ldt:
        movl    $5,%eax
        MACHDEP_SYSCALL_TRAP

-       jnb     2f
-       jmp     cerror
+       jnb             2f
+       movq    %rax, %rdi
+       jmp             _cerror

 2:     ret
 
 #endif
 2:     ret
 
 #endif