KVM: VMX: Unify register save/restore across 32 and 64 bit hosts

Signed-off-by: Avi Kivity <avi@qumranet.com>

1 files changed, 36 insertions, 54 deletions

diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 2879880076d0..fc8996b1043b 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -2955,6 +2955,14 @@ static void fixup_rmode_irq(struct vcpu_vmx *vmx)
                 | vmx->rmode.irq.vector;
 }
 
+#ifdef CONFIG_X86_64
+#define R "r"
+#define Q "q"
+#else
+#define R "e"
+#define Q "l"
+#endif
+
 static void vmx_vcpu_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
 {
         struct vcpu_vmx *vmx = to_vmx(vcpu);
@@ -2972,26 +2980,21 @@ static void vmx_vcpu_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
 
         asm(
                 /* Store host registers */
-#ifdef CONFIG_X86_64
-                "push %%rdx; push %%rbp;"
-                "push %%rcx \n\t"
-#else
-                "push %%edx; push %%ebp;"
-                "push %%ecx \n\t"
-#endif
+                "push %%"R"dx; push %%"R"bp;"
+                "push %%"R"cx \n\t"
                 __ex(ASM_VMX_VMWRITE_RSP_RDX) "\n\t"
                 /* Check if vmlaunch of vmresume is needed */
                 "cmpl $0, %c[launched](%0) \n\t"
                 /* Load guest registers.  Don't clobber flags. */
+                "mov %c[cr2](%0), %%"R"ax \n\t"
+                "mov %%"R"ax, %%cr2 \n\t"
+                "mov %c[rax](%0), %%"R"ax \n\t"
+                "mov %c[rbx](%0), %%"R"bx \n\t"
+                "mov %c[rdx](%0), %%"R"dx \n\t"
+                "mov %c[rsi](%0), %%"R"si \n\t"
+                "mov %c[rdi](%0), %%"R"di \n\t"
+                "mov %c[rbp](%0), %%"R"bp \n\t"
 #ifdef CONFIG_X86_64
-                "mov %c[cr2](%0), %%rax \n\t"
-                "mov %%rax, %%cr2 \n\t"
-                "mov %c[rax](%0), %%rax \n\t"
-                "mov %c[rbx](%0), %%rbx \n\t"
-                "mov %c[rdx](%0), %%rdx \n\t"
-                "mov %c[rsi](%0), %%rsi \n\t"
-                "mov %c[rdi](%0), %%rdi \n\t"
-                "mov %c[rbp](%0), %%rbp \n\t"
                 "mov %c[r8](%0),  %%r8  \n\t"
                 "mov %c[r9](%0),  %%r9  \n\t"
                 "mov %c[r10](%0), %%r10 \n\t"
@@ -3000,18 +3003,9 @@ static void vmx_vcpu_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
                 "mov %c[r13](%0), %%r13 \n\t"
                 "mov %c[r14](%0), %%r14 \n\t"
                 "mov %c[r15](%0), %%r15 \n\t"
-                "mov %c[rcx](%0), %%rcx \n\t" /* kills %0 (rcx) */
-#else
-                "mov %c[cr2](%0), %%eax \n\t"
-                "mov %%eax,   %%cr2 \n\t"
-                "mov %c[rax](%0), %%eax \n\t"
-                "mov %c[rbx](%0), %%ebx \n\t"
-                "mov %c[rdx](%0), %%edx \n\t"
-                "mov %c[rsi](%0), %%esi \n\t"
-                "mov %c[rdi](%0), %%edi \n\t"
-                "mov %c[rbp](%0), %%ebp \n\t"
-                "mov %c[rcx](%0), %%ecx \n\t" /* kills %0 (ecx) */
 #endif
+                "mov %c[rcx](%0), %%"R"cx \n\t" /* kills %0 (ecx) */
+
                 /* Enter guest mode */
                 "jne .Llaunched \n\t"
                 __ex(ASM_VMX_VMLAUNCH) "\n\t"
@@ -3019,15 +3013,15 @@ static void vmx_vcpu_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
                 ".Llaunched: " __ex(ASM_VMX_VMRESUME) "\n\t"
                 ".Lkvm_vmx_return: "
                 /* Save guest registers, load host registers, keep flags */
+                "xchg %0,     (%%"R"sp) \n\t"
+                "mov %%"R"ax, %c[rax](%0) \n\t"
+                "mov %%"R"bx, %c[rbx](%0) \n\t"
+                "push"Q" (%%"R"sp); pop"Q" %c[rcx](%0) \n\t"
+                "mov %%"R"dx, %c[rdx](%0) \n\t"
+                "mov %%"R"si, %c[rsi](%0) \n\t"
+                "mov %%"R"di, %c[rdi](%0) \n\t"
+                "mov %%"R"bp, %c[rbp](%0) \n\t"
 #ifdef CONFIG_X86_64
-                "xchg %0,     (%%rsp) \n\t"
-                "mov %%rax, %c[rax](%0) \n\t"
-                "mov %%rbx, %c[rbx](%0) \n\t"
-                "pushq (%%rsp); popq %c[rcx](%0) \n\t"
-                "mov %%rdx, %c[rdx](%0) \n\t"
-                "mov %%rsi, %c[rsi](%0) \n\t"
-                "mov %%rdi, %c[rdi](%0) \n\t"
-                "mov %%rbp, %c[rbp](%0) \n\t"
                 "mov %%r8,  %c[r8](%0) \n\t"
                 "mov %%r9,  %c[r9](%0) \n\t"
                 "mov %%r10, %c[r10](%0) \n\t"
@@ -3036,24 +3030,11 @@ static void vmx_vcpu_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
                 "mov %%r13, %c[r13](%0) \n\t"
                 "mov %%r14, %c[r14](%0) \n\t"
                 "mov %%r15, %c[r15](%0) \n\t"
-                "mov %%cr2, %%rax   \n\t"
-                "mov %%rax, %c[cr2](%0) \n\t"
-
-                "pop  %%rbp; pop  %%rbp; pop  %%rdx \n\t"
-#else
-                "xchg %0, (%%esp) \n\t"
-                "mov %%eax, %c[rax](%0) \n\t"
-                "mov %%ebx, %c[rbx](%0) \n\t"
-                "pushl (%%esp); popl %c[rcx](%0) \n\t"
-                "mov %%edx, %c[rdx](%0) \n\t"
-                "mov %%esi, %c[rsi](%0) \n\t"
-                "mov %%edi, %c[rdi](%0) \n\t"
-                "mov %%ebp, %c[rbp](%0) \n\t"
-                "mov %%cr2, %%eax  \n\t"
-                "mov %%eax, %c[cr2](%0) \n\t"
-
-                "pop %%ebp; pop %%ebp; pop %%edx \n\t"
 #endif
+                "mov %%cr2, %%"R"ax   \n\t"
+                "mov %%"R"ax, %c[cr2](%0) \n\t"
+
+                "pop  %%"R"bp; pop  %%"R"bp; pop  %%"R"dx \n\t"
                 "setbe %c[fail](%0) \n\t"
               : : "c"(vmx), "d"((unsigned long)HOST_RSP),
                 [launched]"i"(offsetof(struct vcpu_vmx, launched)),
@@ -3077,11 +3058,9 @@ static void vmx_vcpu_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
 #endif
                 [cr2]"i"(offsetof(struct vcpu_vmx, vcpu.arch.cr2))
               : "cc", "memory"
+                , R"bx", R"di", R"si"
 #ifdef CONFIG_X86_64
-                , "rbx", "rdi", "rsi"
                 , "r8", "r9", "r10", "r11", "r12", "r13", "r14", "r15"
-#else
-                , "ebx", "edi", "rsi"
 #endif
               );
 
@@ -3111,6 +3090,9 @@ static void vmx_vcpu_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
         vmx_complete_interrupts(vmx);
 }
 
+#undef R
+#undef Q
+
 static void vmx_free_vmcs(struct kvm_vcpu *vcpu)
 {
         struct vcpu_vmx *vmx = to_vmx(vcpu);