KVM: PPC: Clean up redundant kvm_run parameters in assembly

In the current kvm version, 'kvm_run' has been included in the 'kvm_vcpu'
structure. For historical reasons, many kvm-related function parameters
retain the 'kvm_run' and 'kvm_vcpu' parameters at the same time. This
patch does a unified cleanup of these remaining redundant parameters.

[paulus@ozlabs.org - Fixed places that were missed in book3s_interrupts.S]
Signed-off-by: Tianjia Zhang <tianjia.zhang@linux.alibaba.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>

arch/powerpc/include/asm/kvm_ppc.h

@@ -59,7 +59,7 @@ enum xlate_readwrite {
 };
 
 extern int kvmppc_vcpu_run(struct kvm_vcpu *vcpu);
-extern int __kvmppc_vcpu_run(struct kvm_run *run, struct kvm_vcpu *vcpu);
+extern int __kvmppc_vcpu_run(struct kvm_vcpu *vcpu);
 extern void kvmppc_handler_highmem(void);
 
 extern void kvmppc_dump_vcpu(struct kvm_vcpu *vcpu);

arch/powerpc/kvm/book3s_interrupts.S

@@ -55,8 +55,7 @@
  ****************************************************************************/
 
 /* Registers:
- *  r3: kvm_run pointer
- *  r4: vcpu pointer
+ *  r3: vcpu pointer
  */
 _GLOBAL(__kvmppc_vcpu_run)
 
@@ -68,8 +67,8 @@ kvm_start_entry:
 	/* Save host state to the stack */
 	PPC_STLU r1, -SWITCH_FRAME_SIZE(r1)
 
-	/* Save r3 (kvm_run) and r4 (vcpu) */
-	SAVE_2GPRS(3, r1)
+	/* Save r3 (vcpu) */
+	SAVE_GPR(3, r1)
 
 	/* Save non-volatile registers (r14 - r31) */
 	SAVE_NVGPRS(r1)
@@ -82,47 +81,46 @@ kvm_start_entry:
 	PPC_STL	r0, _LINK(r1)
 
 	/* Load non-volatile guest state from the vcpu */
-	VCPU_LOAD_NVGPRS(r4)
+	VCPU_LOAD_NVGPRS(r3)
 
 kvm_start_lightweight:
 	/* Copy registers into shadow vcpu so we can access them in real mode */
-	mr	r3, r4
 	bl	FUNC(kvmppc_copy_to_svcpu)
 	nop
-	REST_GPR(4, r1)
+	REST_GPR(3, r1)
 
 #ifdef CONFIG_PPC_BOOK3S_64
 	/* Get the dcbz32 flag */
-	PPC_LL	r3, VCPU_HFLAGS(r4)
-	rldicl	r3, r3, 0, 63		/* r3 &= 1 */
-	stb	r3, HSTATE_RESTORE_HID5(r13)
+	PPC_LL	r0, VCPU_HFLAGS(r3)
+	rldicl	r0, r0, 0, 63		/* r3 &= 1 */
+	stb	r0, HSTATE_RESTORE_HID5(r13)
 
 	/* Load up guest SPRG3 value, since it's user readable */
-	lwz	r3, VCPU_SHAREDBE(r4)
-	cmpwi	r3, 0
-	ld	r5, VCPU_SHARED(r4)
+	lbz	r4, VCPU_SHAREDBE(r3)
+	cmpwi	r4, 0
+	ld	r5, VCPU_SHARED(r3)
 	beq	sprg3_little_endian
 sprg3_big_endian:
 #ifdef __BIG_ENDIAN__
-	ld	r3, VCPU_SHARED_SPRG3(r5)
+	ld	r4, VCPU_SHARED_SPRG3(r5)
 #else
 	addi	r5, r5, VCPU_SHARED_SPRG3
-	ldbrx	r3, 0, r5
+	ldbrx	r4, 0, r5
 #endif
 	b	after_sprg3_load
 sprg3_little_endian:
 #ifdef __LITTLE_ENDIAN__
-	ld	r3, VCPU_SHARED_SPRG3(r5)
+	ld	r4, VCPU_SHARED_SPRG3(r5)
 #else
 	addi	r5, r5, VCPU_SHARED_SPRG3
-	ldbrx	r3, 0, r5
+	ldbrx	r4, 0, r5
 #endif
 
 after_sprg3_load:
-	mtspr	SPRN_SPRG3, r3
+	mtspr	SPRN_SPRG3, r4
 #endif /* CONFIG_PPC_BOOK3S_64 */
 
-	PPC_LL	r4, VCPU_SHADOW_MSR(r4)	/* get shadow_msr */
+	PPC_LL	r4, VCPU_SHADOW_MSR(r3)	/* get shadow_msr */
 
 	/* Jump to segment patching handler and into our guest */
 	bl	FUNC(kvmppc_entry_trampoline)
@@ -146,7 +144,7 @@ after_sprg3_load:
 	 *
 	 */
 
-	PPC_LL	r3, GPR4(r1)		/* vcpu pointer */
+	PPC_LL	r3, GPR3(r1)		/* vcpu pointer */
 
 	/*
 	 * kvmppc_copy_from_svcpu can clobber volatile registers, save
@@ -169,7 +167,7 @@ after_sprg3_load:
 #endif /* CONFIG_PPC_BOOK3S_64 */
 
 	/* R7 = vcpu */
-	PPC_LL	r7, GPR4(r1)
+	PPC_LL	r7, GPR3(r1)
 
 	PPC_STL	r14, VCPU_GPR(R14)(r7)
 	PPC_STL	r15, VCPU_GPR(R15)(r7)
@@ -190,11 +188,11 @@ after_sprg3_load:
 	PPC_STL	r30, VCPU_GPR(R30)(r7)
 	PPC_STL	r31, VCPU_GPR(R31)(r7)
 
-	/* Pass the exit number as 3rd argument to kvmppc_handle_exit */
-	lwz	r5, VCPU_TRAP(r7)
+	/* Pass the exit number as 2nd argument to kvmppc_handle_exit */
+	lwz	r4, VCPU_TRAP(r7)
 
-	/* Restore r3 (kvm_run) and r4 (vcpu) */
-	REST_2GPRS(3, r1)
+	/* Restore r3 (vcpu) */
+	REST_GPR(3, r1)
 	bl	FUNC(kvmppc_handle_exit_pr)
 
 	/* If RESUME_GUEST, get back in the loop */
@@ -223,11 +221,11 @@ kvm_loop_heavyweight:
 	PPC_LL	r4, _LINK(r1)
 	PPC_STL r4, (PPC_LR_STKOFF + SWITCH_FRAME_SIZE)(r1)
 
-	/* Load vcpu and cpu_run */
-	REST_2GPRS(3, r1)
+	/* Load vcpu */
+	REST_GPR(3, r1)
 
 	/* Load non-volatile guest state from the vcpu */
-	VCPU_LOAD_NVGPRS(r4)
+	VCPU_LOAD_NVGPRS(r3)
 
 	/* Jump back into the beginning of this function */
 	b	kvm_start_lightweight
@@ -235,7 +233,7 @@ kvm_loop_heavyweight:
 kvm_loop_lightweight:
 
 	/* We'll need the vcpu pointer */
-	REST_GPR(4, r1)
+	REST_GPR(3, r1)
 
 	/* Jump back into the beginning of this function */
 	b	kvm_start_lightweight

arch/powerpc/kvm/book3s_pr.c

@@ -1151,9 +1151,9 @@ static int kvmppc_exit_pr_progint(struct kvm_vcpu *vcpu, unsigned int exit_nr)
 	return r;
 }
 
-int kvmppc_handle_exit_pr(struct kvm_run *run, struct kvm_vcpu *vcpu,
-			  unsigned int exit_nr)
+int kvmppc_handle_exit_pr(struct kvm_vcpu *vcpu, unsigned int exit_nr)
 {
+	struct kvm_run *run = vcpu->run;
 	int r = RESUME_HOST;
 	int s;
 
@@ -1826,7 +1826,6 @@ static void kvmppc_core_vcpu_free_pr(struct kvm_vcpu *vcpu)
 
 static int kvmppc_vcpu_run_pr(struct kvm_vcpu *vcpu)
 {
-	struct kvm_run *run = vcpu->run;
 	int ret;
 #ifdef CONFIG_ALTIVEC
 	unsigned long uninitialized_var(vrsave);
@@ -1834,7 +1833,7 @@ static int kvmppc_vcpu_run_pr(struct kvm_vcpu *vcpu)
 
 	/* Check if we can run the vcpu at all */
 	if (!vcpu->arch.sane) {
-		run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
+		vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
 		ret = -EINVAL;
 		goto out;
 	}
@@ -1861,7 +1860,7 @@ static int kvmppc_vcpu_run_pr(struct kvm_vcpu *vcpu)
 
 	kvmppc_fix_ee_before_entry();
 
-	ret = __kvmppc_vcpu_run(run, vcpu);
+	ret = __kvmppc_vcpu_run(vcpu);
 
 	kvmppc_clear_debug(vcpu);
 

arch/powerpc/kvm/booke.c

@@ -731,12 +731,11 @@ int kvmppc_core_check_requests(struct kvm_vcpu *vcpu)
 
 int kvmppc_vcpu_run(struct kvm_vcpu *vcpu)
 {
-	struct kvm_run *run = vcpu->run;
 	int ret, s;
 	struct debug_reg debug;
 
 	if (!vcpu->arch.sane) {
-		run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
+		vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
 		return -EINVAL;
 	}
 
@@ -778,7 +777,7 @@ int kvmppc_vcpu_run(struct kvm_vcpu *vcpu)
 	vcpu->arch.pgdir = vcpu->kvm->mm->pgd;
 	kvmppc_fix_ee_before_entry();
 
-	ret = __kvmppc_vcpu_run(run, vcpu);
+	ret = __kvmppc_vcpu_run(vcpu);
 
 	/* No need for guest_exit. It's done in handle_exit.
 	   We also get here with interrupts enabled. */
@@ -982,9 +981,9 @@ static int kvmppc_resume_inst_load(struct kvm_vcpu *vcpu,
  *
  * Return value is in the form (errcode<<2 | RESUME_FLAG_HOST | RESUME_FLAG_NV)
  */
-int kvmppc_handle_exit(struct kvm_run *run, struct kvm_vcpu *vcpu,
-                       unsigned int exit_nr)
+int kvmppc_handle_exit(struct kvm_vcpu *vcpu, unsigned int exit_nr)
 {
+	struct kvm_run *run = vcpu->run;
 	int r = RESUME_HOST;
 	int s;
 	int idx;

arch/powerpc/kvm/booke_interrupts.S

@@ -237,7 +237,7 @@ _GLOBAL(kvmppc_resume_host)
 	/* Switch to kernel stack and jump to handler. */
 	LOAD_REG_ADDR(r3, kvmppc_handle_exit)
 	mtctr	r3
-	lwz	r3, HOST_RUN(r1)
+	mr	r3, r4
 	lwz	r2, HOST_R2(r1)
 	mr	r14, r4 /* Save vcpu pointer. */
 
@@ -337,15 +337,14 @@ heavyweight_exit:
 
 
 /* Registers:
- *  r3: kvm_run pointer
- *  r4: vcpu pointer
+ *  r3: vcpu pointer
  */
 _GLOBAL(__kvmppc_vcpu_run)
 	stwu	r1, -HOST_STACK_SIZE(r1)
-	stw	r1, VCPU_HOST_STACK(r4)	/* Save stack pointer to vcpu. */
+	stw	r1, VCPU_HOST_STACK(r3)	/* Save stack pointer to vcpu. */
 
 	/* Save host state to stack. */
-	stw	r3, HOST_RUN(r1)
+	mr	r4, r3
 	mflr	r3
 	stw	r3, HOST_STACK_LR(r1)
 	mfcr	r5

arch/powerpc/kvm/bookehv_interrupts.S

@@ -434,9 +434,10 @@ _GLOBAL(kvmppc_resume_host)
 #endif
 
 	/* Switch to kernel stack and jump to handler. */
-	PPC_LL	r3, HOST_RUN(r1)
+	mr	r3, r4
 	mr	r5, r14 /* intno */
 	mr	r14, r4 /* Save vcpu pointer. */
+	mr	r4, r5
 	bl	kvmppc_handle_exit
 
 	/* Restore vcpu pointer and the nonvolatiles we used. */
@@ -525,15 +526,14 @@ heavyweight_exit:
 	blr
 
 /* Registers:
- *  r3: kvm_run pointer
- *  r4: vcpu pointer
+ *  r3: vcpu pointer
  */
 _GLOBAL(__kvmppc_vcpu_run)
 	stwu	r1, -HOST_STACK_SIZE(r1)
-	PPC_STL	r1, VCPU_HOST_STACK(r4)	/* Save stack pointer to vcpu. */
+	PPC_STL	r1, VCPU_HOST_STACK(r3)	/* Save stack pointer to vcpu. */
 
 	/* Save host state to stack. */
-	PPC_STL	r3, HOST_RUN(r1)
+	mr	r4, r3
 	mflr	r3
 	mfcr	r5
 	PPC_STL	r3, HOST_STACK_LR(r1)