KVM: arm64: Share context save and restore macros

To avoid duplicating the context save and restore macros, move them into
a shareable header.
Signed-off-by: Andrew Scull <ascull@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200915104643.2543892-12-ascull@google.com

arch/arm64/include/asm/kvm_asm.h

@@ -261,6 +261,45 @@ extern char __smccc_workaround_1_smc[__SMCCC_WORKAROUND_1_SMC_SZ];
 	.popsection
 .endm
 
+#define CPU_XREG_OFFSET(x)	(CPU_USER_PT_REGS + 8*x)
+#define CPU_LR_OFFSET		CPU_XREG_OFFSET(30)
+#define CPU_SP_EL0_OFFSET	(CPU_LR_OFFSET + 8)
+
+/*
+ * We treat x18 as callee-saved as the host may use it as a platform
+ * register (e.g. for shadow call stack).
+ */
+.macro save_callee_saved_regs ctxt
+	str	x18,      [\ctxt, #CPU_XREG_OFFSET(18)]
+	stp	x19, x20, [\ctxt, #CPU_XREG_OFFSET(19)]
+	stp	x21, x22, [\ctxt, #CPU_XREG_OFFSET(21)]
+	stp	x23, x24, [\ctxt, #CPU_XREG_OFFSET(23)]
+	stp	x25, x26, [\ctxt, #CPU_XREG_OFFSET(25)]
+	stp	x27, x28, [\ctxt, #CPU_XREG_OFFSET(27)]
+	stp	x29, lr,  [\ctxt, #CPU_XREG_OFFSET(29)]
+.endm
+
+.macro restore_callee_saved_regs ctxt
+	// We require \ctxt is not x18-x28
+	ldr	x18,      [\ctxt, #CPU_XREG_OFFSET(18)]
+	ldp	x19, x20, [\ctxt, #CPU_XREG_OFFSET(19)]
+	ldp	x21, x22, [\ctxt, #CPU_XREG_OFFSET(21)]
+	ldp	x23, x24, [\ctxt, #CPU_XREG_OFFSET(23)]
+	ldp	x25, x26, [\ctxt, #CPU_XREG_OFFSET(25)]
+	ldp	x27, x28, [\ctxt, #CPU_XREG_OFFSET(27)]
+	ldp	x29, lr,  [\ctxt, #CPU_XREG_OFFSET(29)]
+.endm
+
+.macro save_sp_el0 ctxt, tmp
+	mrs	\tmp,	sp_el0
+	str	\tmp,	[\ctxt, #CPU_SP_EL0_OFFSET]
+.endm
+
+.macro restore_sp_el0 ctxt, tmp
+	ldr	\tmp,	  [\ctxt, #CPU_SP_EL0_OFFSET]
+	msr	sp_el0, \tmp
+.endm
+
 #endif
 
 #endif /* __ARM_KVM_ASM_H__ */

arch/arm64/kvm/hyp/entry.S

@@ -7,7 +7,6 @@
 #include <linux/linkage.h>
 
 #include <asm/alternative.h>
-#include <asm/asm-offsets.h>
 #include <asm/assembler.h>
 #include <asm/fpsimdmacros.h>
 #include <asm/kvm.h>
@@ -16,46 +15,8 @@
 #include <asm/kvm_mmu.h>
 #include <asm/kvm_ptrauth.h>
 
-#define CPU_XREG_OFFSET(x)	(CPU_USER_PT_REGS + 8*x)
-#define CPU_SP_EL0_OFFSET	(CPU_XREG_OFFSET(30) + 8)
-
 	.text
 
-/*
- * We treat x18 as callee-saved as the host may use it as a platform
- * register (e.g. for shadow call stack).
- */
-.macro save_callee_saved_regs ctxt
-	str	x18,      [\ctxt, #CPU_XREG_OFFSET(18)]
-	stp	x19, x20, [\ctxt, #CPU_XREG_OFFSET(19)]
-	stp	x21, x22, [\ctxt, #CPU_XREG_OFFSET(21)]
-	stp	x23, x24, [\ctxt, #CPU_XREG_OFFSET(23)]
-	stp	x25, x26, [\ctxt, #CPU_XREG_OFFSET(25)]
-	stp	x27, x28, [\ctxt, #CPU_XREG_OFFSET(27)]
-	stp	x29, lr,  [\ctxt, #CPU_XREG_OFFSET(29)]
-.endm
-
-.macro restore_callee_saved_regs ctxt
-	// We require \ctxt is not x18-x28
-	ldr	x18,      [\ctxt, #CPU_XREG_OFFSET(18)]
-	ldp	x19, x20, [\ctxt, #CPU_XREG_OFFSET(19)]
-	ldp	x21, x22, [\ctxt, #CPU_XREG_OFFSET(21)]
-	ldp	x23, x24, [\ctxt, #CPU_XREG_OFFSET(23)]
-	ldp	x25, x26, [\ctxt, #CPU_XREG_OFFSET(25)]
-	ldp	x27, x28, [\ctxt, #CPU_XREG_OFFSET(27)]
-	ldp	x29, lr,  [\ctxt, #CPU_XREG_OFFSET(29)]
-.endm
-
-.macro save_sp_el0 ctxt, tmp
-	mrs	\tmp,	sp_el0
-	str	\tmp,	[\ctxt, #CPU_SP_EL0_OFFSET]
-.endm
-
-.macro restore_sp_el0 ctxt, tmp
-	ldr	\tmp,	  [\ctxt, #CPU_SP_EL0_OFFSET]
-	msr	sp_el0, \tmp
-.endm
-
 /*
  * u64 __guest_enter(struct kvm_vcpu *vcpu);
  */