[PATCH 2/3] KVM: SVM: Macrofy GPR swapping in __svm_vcpu_run()

[Paolo Bonzini]

From: "Chang S. Bae" <chang.seok.bae@xxxxxxxxx>

Convert the register save/restore sequences in the SVM entry into macros,
following the VMX code. Drop the now-redundant register offset defines.

No functional change intended.

Signed-off-by: Chang S. Bae <chang.seok.bae@xxxxxxxxx>
Message-ID: <20260512011502.53072-3-chang.seok.bae@xxxxxxxxx>
Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
---
 arch/x86/kvm/svm/vmenter.S | 83 +++++++++-----------------------------
 1 file changed, 19 insertions(+), 64 deletions(-)

diff --git a/arch/x86/kvm/svm/vmenter.S b/arch/x86/kvm/svm/vmenter.S
index 6a91e1383e8f..06a8cb58f187 100644
--- a/arch/x86/kvm/svm/vmenter.S
+++ b/arch/x86/kvm/svm/vmenter.S
@@ -8,26 +8,6 @@
 #include "kvm-asm-offsets.h"
 #include "vmenter.h"
 
-/* Intentionally omit RAX as it's context switched by hardware */
-#define VCPU_RCX	(SVM_vcpu_arch_regs + __VCPU_REGS_RCX * WORD_SIZE)
-#define VCPU_RDX	(SVM_vcpu_arch_regs + __VCPU_REGS_RDX * WORD_SIZE)
-#define VCPU_RBX	(SVM_vcpu_arch_regs + __VCPU_REGS_RBX * WORD_SIZE)
-/* Intentionally omit RSP as it's context switched by hardware */
-#define VCPU_RBP	(SVM_vcpu_arch_regs + __VCPU_REGS_RBP * WORD_SIZE)
-#define VCPU_RSI	(SVM_vcpu_arch_regs + __VCPU_REGS_RSI * WORD_SIZE)
-#define VCPU_RDI	(SVM_vcpu_arch_regs + __VCPU_REGS_RDI * WORD_SIZE)
-
-#ifdef CONFIG_X86_64
-#define VCPU_R8		(SVM_vcpu_arch_regs + __VCPU_REGS_R8  * WORD_SIZE)
-#define VCPU_R9		(SVM_vcpu_arch_regs + __VCPU_REGS_R9  * WORD_SIZE)
-#define VCPU_R10	(SVM_vcpu_arch_regs + __VCPU_REGS_R10 * WORD_SIZE)
-#define VCPU_R11	(SVM_vcpu_arch_regs + __VCPU_REGS_R11 * WORD_SIZE)
-#define VCPU_R12	(SVM_vcpu_arch_regs + __VCPU_REGS_R12 * WORD_SIZE)
-#define VCPU_R13	(SVM_vcpu_arch_regs + __VCPU_REGS_R13 * WORD_SIZE)
-#define VCPU_R14	(SVM_vcpu_arch_regs + __VCPU_REGS_R14 * WORD_SIZE)
-#define VCPU_R15	(SVM_vcpu_arch_regs + __VCPU_REGS_R15 * WORD_SIZE)
-#endif
-
 #define SVM_vmcb01_pa	(SVM_vmcb01 + KVM_VMCB_pa)
 
 .section .noinstr.text, "ax"
@@ -108,23 +88,17 @@ SYM_FUNC_START(__svm_vcpu_run)
 	mov SVM_current_vmcb(%_ASM_DI), %_ASM_AX
 	mov KVM_VMCB_pa(%_ASM_AX), %_ASM_AX
 
-	/* Load guest registers. */
-	mov VCPU_RCX(%_ASM_DI), %_ASM_CX
-	mov VCPU_RDX(%_ASM_DI), %_ASM_DX
-	mov VCPU_RBX(%_ASM_DI), %_ASM_BX
-	mov VCPU_RBP(%_ASM_DI), %_ASM_BP
-	mov VCPU_RSI(%_ASM_DI), %_ASM_SI
+	/*
+	 * Load guest registers. Intentionally omit %_ASM_AX and %_ASM_SP as
+	 * context switched by hardware
+	 */
+	LOAD_REGS %_ASM_DI, SVM_vcpu_arch_regs, \
+		  %_ASM_CX, %_ASM_DX, %_ASM_BX, %_ASM_BP, %_ASM_SI
 #ifdef CONFIG_X86_64
-	mov VCPU_R8 (%_ASM_DI),  %r8
-	mov VCPU_R9 (%_ASM_DI),  %r9
-	mov VCPU_R10(%_ASM_DI), %r10
-	mov VCPU_R11(%_ASM_DI), %r11
-	mov VCPU_R12(%_ASM_DI), %r12
-	mov VCPU_R13(%_ASM_DI), %r13
-	mov VCPU_R14(%_ASM_DI), %r14
-	mov VCPU_R15(%_ASM_DI), %r15
+	LOAD_REGS %_ASM_DI, SVM_vcpu_arch_regs, \
+		  %r8, %r9, %r10, %r11, %r12, %r13, %r14, %r15
 #endif
-	mov VCPU_RDI(%_ASM_DI), %_ASM_DI
+	LOAD_REGS %_ASM_DI, SVM_vcpu_arch_regs, %_ASM_DI
 
 	/* Clobbers EFLAGS.ZF */
 	SVM_CLEAR_CPU_BUFFERS
@@ -135,22 +109,15 @@ SYM_FUNC_START(__svm_vcpu_run)
 	/* Pop @svm to RAX while it's the only available register. */
 	pop %_ASM_AX
 
-	/* Save all guest registers.  */
-	mov %_ASM_CX,   VCPU_RCX(%_ASM_AX)
-	mov %_ASM_DX,   VCPU_RDX(%_ASM_AX)
-	mov %_ASM_BX,   VCPU_RBX(%_ASM_AX)
-	mov %_ASM_BP,   VCPU_RBP(%_ASM_AX)
-	mov %_ASM_SI,   VCPU_RSI(%_ASM_AX)
-	mov %_ASM_DI,   VCPU_RDI(%_ASM_AX)
+	/*
+	 * Save all guest registers. Intentionally omit %_ASM_AX and %_ASM_SP as
+	 * context switched by hardware
+	 */
+	STORE_REGS %_ASM_AX, SVM_vcpu_arch_regs, \
+		   %_ASM_CX, %_ASM_DX, %_ASM_BX, %_ASM_BP, %_ASM_SI, %_ASM_DI
 #ifdef CONFIG_X86_64
-	mov %r8,  VCPU_R8 (%_ASM_AX)
-	mov %r9,  VCPU_R9 (%_ASM_AX)
-	mov %r10, VCPU_R10(%_ASM_AX)
-	mov %r11, VCPU_R11(%_ASM_AX)
-	mov %r12, VCPU_R12(%_ASM_AX)
-	mov %r13, VCPU_R13(%_ASM_AX)
-	mov %r14, VCPU_R14(%_ASM_AX)
-	mov %r15, VCPU_R15(%_ASM_AX)
+	STORE_REGS %_ASM_AX, SVM_vcpu_arch_regs, \
+		   %r8, %r9, %r10, %r11, %r12, %r13, %r14, %r15
 #endif
 
 	/* @svm can stay in RDI from now on.  */
@@ -193,21 +160,9 @@ SYM_FUNC_START(__svm_vcpu_run)
 	 * free.  RSP and RAX are exempt as they are restored by hardware
 	 * during VM-Exit.
 	 */
-	xor %ecx, %ecx
-	xor %edx, %edx
-	xor %ebx, %ebx
-	xor %ebp, %ebp
-	xor %esi, %esi
-	xor %edi, %edi
+	CLEAR_REGS %ecx, %edx, %ebx, %ebp, %esi, %edi
 #ifdef CONFIG_X86_64
-	xor %r8d,  %r8d
-	xor %r9d,  %r9d
-	xor %r10d, %r10d
-	xor %r11d, %r11d
-	xor %r12d, %r12d
-	xor %r13d, %r13d
-	xor %r14d, %r14d
-	xor %r15d, %r15d
+	CLEAR_REGS %r8d, %r9d, %r10d, %r11d, %r12d, %r13d, %r14d, %r15d
 #endif
 
 	/* "Pop" @enter_flags.  */
-- 
2.52.0