[11/39] KVM: PPC: Call SLB patching code in interrupt safe manner

Commit Message

Avi Kivity Feb. 13, 2010, 8:01 a.m. UTC

None

Patch

diff --git a/arch/powerpc/include/asm/kvm_book3s.h b/arch/powerpc/include/asm/kvm_book3s.h
index f192017..c91be0f 100644
--- a/arch/powerpc/include/asm/kvm_book3s.h
+++ b/arch/powerpc/include/asm/kvm_book3s.h
@@ -121,6 +121,7 @@  extern void kvmppc_set_bat(struct kvm_vcpu *vcpu, struct kvmppc_bat *bat,
 
 extern u32 kvmppc_trampoline_lowmem;
 extern u32 kvmppc_trampoline_enter;
+extern void kvmppc_rmcall(ulong srr0, ulong srr1);
 
 static inline struct kvmppc_vcpu_book3s *to_book3s(struct kvm_vcpu *vcpu)
 {
diff --git a/arch/powerpc/include/asm/kvm_book3s_64_asm.h b/arch/powerpc/include/asm/kvm_book3s_64_asm.h
index fca9404..183461b 100644
--- a/arch/powerpc/include/asm/kvm_book3s_64_asm.h
+++ b/arch/powerpc/include/asm/kvm_book3s_64_asm.h
@@ -69,7 +69,6 @@  struct kvmppc_book3s_shadow_vcpu {
 	ulong scratch0;
 	ulong scratch1;
 	ulong vmhandler;
-	ulong rmhandler;
 };
 
 #endif /*__ASSEMBLY__ */
diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h
index d615fa8..f7215e6 100644
--- a/arch/powerpc/include/asm/kvm_host.h
+++ b/arch/powerpc/include/asm/kvm_host.h
@@ -167,6 +167,7 @@  struct kvm_vcpu_arch {
 	ulong trampoline_lowmem;
 	ulong trampoline_enter;
 	ulong highmem_handler;
+	ulong rmcall;
 	ulong host_paca_phys;
 	struct kvmppc_mmu mmu;
 #endif
diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c
index 1501e77..ee99354 100644
--- a/arch/powerpc/kernel/asm-offsets.c
+++ b/arch/powerpc/kernel/asm-offsets.c
@@ -214,8 +214,6 @@  int main(void)
 	DEFINE(PACA_KVM_HOST_R2, offsetof(struct paca_struct, shadow_vcpu.host_r2));
 	DEFINE(PACA_KVM_VMHANDLER, offsetof(struct paca_struct,
 					    shadow_vcpu.vmhandler));
-	DEFINE(PACA_KVM_RMHANDLER, offsetof(struct paca_struct,
-					    shadow_vcpu.rmhandler));
 	DEFINE(PACA_KVM_SCRATCH0, offsetof(struct paca_struct,
 					   shadow_vcpu.scratch0));
 	DEFINE(PACA_KVM_SCRATCH1, offsetof(struct paca_struct,
@@ -438,6 +436,7 @@  int main(void)
 	DEFINE(VCPU_TRAMPOLINE_LOWMEM, offsetof(struct kvm_vcpu, arch.trampoline_lowmem));
 	DEFINE(VCPU_TRAMPOLINE_ENTER, offsetof(struct kvm_vcpu, arch.trampoline_enter));
 	DEFINE(VCPU_HIGHMEM_HANDLER, offsetof(struct kvm_vcpu, arch.highmem_handler));
+	DEFINE(VCPU_RMCALL, offsetof(struct kvm_vcpu, arch.rmcall));
 	DEFINE(VCPU_HFLAGS, offsetof(struct kvm_vcpu, arch.hflags));
 #else
 	DEFINE(VCPU_CR, offsetof(struct kvm_vcpu, arch.cr));
diff --git a/arch/powerpc/kvm/book3s.c b/arch/powerpc/kvm/book3s.c
index 3e06eae..1317392 100644
--- a/arch/powerpc/kvm/book3s.c
+++ b/arch/powerpc/kvm/book3s.c
@@ -919,6 +919,7 @@  struct kvm_vcpu *kvmppc_core_vcpu_create(struct kvm *kvm, unsigned int id)
 	vcpu->arch.trampoline_lowmem = kvmppc_trampoline_lowmem;
 	vcpu->arch.trampoline_enter = kvmppc_trampoline_enter;
 	vcpu->arch.highmem_handler = (ulong)kvmppc_handler_highmem;
+	vcpu->arch.rmcall = *(ulong*)kvmppc_rmcall;
 
 	vcpu->arch.shadow_msr = MSR_USER64;
 
diff --git a/arch/powerpc/kvm/book3s_64_exports.c b/arch/powerpc/kvm/book3s_64_exports.c
index 5b2db38..99b0712 100644
--- a/arch/powerpc/kvm/book3s_64_exports.c
+++ b/arch/powerpc/kvm/book3s_64_exports.c
@@ -22,3 +22,4 @@ 
 
 EXPORT_SYMBOL_GPL(kvmppc_trampoline_enter);
 EXPORT_SYMBOL_GPL(kvmppc_trampoline_lowmem);
+EXPORT_SYMBOL_GPL(kvmppc_rmcall);
diff --git a/arch/powerpc/kvm/book3s_64_interrupts.S b/arch/powerpc/kvm/book3s_64_interrupts.S
index 3c0ba55..33aef53 100644
--- a/arch/powerpc/kvm/book3s_64_interrupts.S
+++ b/arch/powerpc/kvm/book3s_64_interrupts.S
@@ -95,17 +95,14 @@  kvm_start_entry:
 	ld	r3, VCPU_HIGHMEM_HANDLER(r4)
 	std	r3, PACA_KVM_VMHANDLER(r13)
 
-	ld	r3, VCPU_TRAMPOLINE_ENTER(r4)
-	std	r3, PACA_KVM_RMHANDLER(r13)
-
 kvm_start_lightweight:
 
 	ld	r9, VCPU_PC(r4)			/* r9 = vcpu->arch.pc */
 	ld	r10, VCPU_SHADOW_MSR(r4)	/* r10 = vcpu->arch.shadow_msr */
 
 	/* Load some guest state in the respective registers */
-	ld	r3, VCPU_CTR(r4)	/* r3 = vcpu->arch.ctr */
-	mtctr	r3			/* CTR = r3 */
+	ld	r5, VCPU_CTR(r4)	/* r5 = vcpu->arch.ctr */
+					/* will be swapped in by rmcall */
 
 	ld	r3, VCPU_LR(r4)		/* r3 = vcpu->arch.lr */
 	mtlr	r3			/* LR = r3 */
@@ -131,22 +128,14 @@  kvm_start_lightweight:
 
 no_dcbz32_on:
 
-	/* This sets the Magic value for the trampoline */
-
-	/* XXX this needs to move into a safe function, so we can
-	   be sure we don't get any interrupts */
-
-	li	r11, 1
-	stb	r11, PACA_KVM_IN_GUEST(r13)
-
-	ld	r3, PACA_KVM_RMHANDLER(r13)
-	mtsrr0	r3
+	ld	r6, VCPU_RMCALL(r4)
+	mtctr	r6
 
-	LOAD_REG_IMMEDIATE(r3, MSR_KERNEL & ~(MSR_IR | MSR_DR))
-	mtsrr1	r3
+	ld	r3, VCPU_TRAMPOLINE_ENTER(r4)
+	LOAD_REG_IMMEDIATE(r4, MSR_KERNEL & ~(MSR_IR | MSR_DR))
 
 	/* Jump to SLB patching handlder and into our guest */
-	RFI
+	bctr
 
 /*
  * This is the handler in module memory. It gets jumped at from the
diff --git a/arch/powerpc/kvm/book3s_64_rmhandlers.S b/arch/powerpc/kvm/book3s_64_rmhandlers.S
index 9ad1c26..e7091c9 100644
--- a/arch/powerpc/kvm/book3s_64_rmhandlers.S
+++ b/arch/powerpc/kvm/book3s_64_rmhandlers.S
@@ -140,6 +140,24 @@  kvmppc_handler_lowmem_trampoline:
 	blr
 kvmppc_handler_lowmem_trampoline_end:
 
+/*
+ * Call a function in real mode
+ *
+ * Input Registers:
+ *
+ * R3 = function
+ * R4 = MSR
+ * R5 = CTR
+ *
+ */
+_GLOBAL(kvmppc_rmcall)
+	mtmsr	r4		/* Disable relocation, so mtsrr
+				   doesn't get interrupted */
+	mtctr	r5
+	mtsrr0	r3
+	mtsrr1	r4
+	RFI
+
 .global kvmppc_trampoline_lowmem
 kvmppc_trampoline_lowmem:
 	.long kvmppc_handler_lowmem_trampoline - _stext
diff --git a/arch/powerpc/kvm/book3s_64_slb.S b/arch/powerpc/kvm/book3s_64_slb.S
index d07b886..35b7627 100644
--- a/arch/powerpc/kvm/book3s_64_slb.S
+++ b/arch/powerpc/kvm/book3s_64_slb.S
@@ -63,6 +63,10 @@  kvmppc_handler_trampoline_enter:
 	mtsrr0	r9
 	mtsrr1	r10
 
+	/* Activate guest mode, so faults get handled by KVM */
+	li	r11, KVM_GUEST_MODE_GUEST
+	stb	r11, PACA_KVM_IN_GUEST(r13)
+
 	/* Remove LPAR shadow entries */
 
 #if SLB_NUM_BOLTED == 3