Simplify vmx instruction error handling.

Removes jumps and shortens the code while keeping functionality the
same.

ok mlarkin@

diff --git a/sys/arch/amd64/amd64/vmm_support.S b/sys/arch/amd64/amd64/vmm_support.S
index 3be2f29..cb500f5 100644 (file)
--- a/sys/arch/amd64/amd64/vmm_support.S
+++ b/sys/arch/amd64/amd64/vmm_support.S
@@ -1,4 +1,4 @@
-/*     $OpenBSD: vmm_support.S,v 1.18 2021/09/04 22:15:33 bluhm Exp $  */
+/*     $OpenBSD: vmm_support.S,v 1.19 2022/04/09 01:49:43 dv Exp $     */
 /*
  * Copyright (c) 2014 Mike Larkin <mlarkin@openbsd.org>
  *
@@ -63,14 +63,8 @@ _C_LABEL(vmm_dispatch_intr):
 _C_LABEL(vmxon):
        RETGUARD_SETUP(vmxon, r11)
        vmxon   (%rdi)
-       jz      failed_on
-       jc      failed_on
        xorq    %rax, %rax
-       RETGUARD_CHECK(vmxon, r11)
-       ret
-       lfence
-failed_on:
-       movq    $0x01, %rax
+       setna   %al
        RETGUARD_CHECK(vmxon, r11)
        ret
        lfence
@@ -78,14 +72,8 @@ failed_on:
 _C_LABEL(vmxoff):
        RETGUARD_SETUP(vmxoff, r11)
        vmxoff
-       jz      failed_off
-       jc      failed_off
        xorq    %rax, %rax
-       RETGUARD_CHECK(vmxoff, r11)
-       ret
-       lfence
-failed_off:
-       movq    $0x01, %rax
+       setna   %al
        RETGUARD_CHECK(vmxoff, r11)
        ret
        lfence
@@ -93,14 +81,8 @@ failed_off:
 _C_LABEL(vmclear):
        RETGUARD_SETUP(vmclear, r11)
        vmclear (%rdi)
-       jz      failed_clear
-       jc      failed_clear
        xorq    %rax, %rax
-       RETGUARD_CHECK(vmclear, r11)
-       ret
-       lfence
-failed_clear:
-       movq    $0x01, %rax
+       setna   %al
        RETGUARD_CHECK(vmclear, r11)
        ret
        lfence
@@ -108,14 +90,8 @@ failed_clear:
 _C_LABEL(vmptrld):
        RETGUARD_SETUP(vmptrld, r11)
        vmptrld (%rdi)
-       jz      failed_ptrld
-       jc      failed_ptrld
        xorq    %rax, %rax
-       RETGUARD_CHECK(vmptrld, r11)
-       ret
-       lfence
-failed_ptrld:
-       movq    $0x01, %rax
+       setna   %al
        RETGUARD_CHECK(vmptrld, r11)
        ret
        lfence
@@ -123,14 +99,8 @@ failed_ptrld:
 _C_LABEL(vmptrst):
        RETGUARD_SETUP(vmptrst, r11)
        vmptrst (%rdi)
-       jz      failed_ptrst
-       jc      failed_ptrst
        xorq    %rax, %rax
-       RETGUARD_CHECK(vmptrst, r11)
-       ret
-       lfence
-failed_ptrst:
-       movq    $0x01, %rax
+       setna   %al
        RETGUARD_CHECK(vmptrst, r11)
        ret
        lfence
@@ -138,14 +108,8 @@ failed_ptrst:
 _C_LABEL(vmwrite):
        RETGUARD_SETUP(vmwrite, r11)
        vmwrite %rsi, %rdi
-       jz      failed_write
-       jc      failed_write
        xorq    %rax, %rax
-       RETGUARD_CHECK(vmwrite, r11)
-       ret
-       lfence
-failed_write:
-       movq    $0x01, %rax
+       setna   %al
        RETGUARD_CHECK(vmwrite, r11)
        ret
        lfence
@@ -153,14 +117,8 @@ failed_write:
 _C_LABEL(vmread):
        RETGUARD_SETUP(vmread, r11)
        vmread  %rdi, (%rsi)
-       jz      failed_read
-       jc      failed_read
        xorq    %rax, %rax
-       RETGUARD_CHECK(vmread, r11)
-       ret
-       lfence
-failed_read:
-       movq    $0x01, %rax
+       setna   %al
        RETGUARD_CHECK(vmread, r11)
        ret
        lfence