[PATCH v9 1/4] arm: add ARMv7 HYP API to flush VM TLBs, change generic TLB flush to support arch flush

[Mario Smarduch]

Patch adds HYP interface for global VM TLB invalidation without address
parameter. Generic VM TLB flush calls ARMv7 arch defined TLB flush function.

Signed-off-by: Mario Smarduch <m.smarduch at samsung.com>
---
 arch/arm/include/asm/kvm_asm.h  |    1 +
 arch/arm/include/asm/kvm_host.h |    1 +
 arch/arm/kvm/Kconfig            |    1 +
 arch/arm/kvm/interrupts.S       |   12 ++++++++++++
 arch/arm/kvm/mmu.c              |   17 +++++++++++++++++
 virt/kvm/Kconfig                |    3 +++
 virt/kvm/kvm_main.c             |    4 ++++
 7 files changed, 39 insertions(+)

diff --git a/arch/arm/include/asm/kvm_asm.h b/arch/arm/include/asm/kvm_asm.h
index 53b3c4a..21bc519 100644
--- a/arch/arm/include/asm/kvm_asm.h
+++ b/arch/arm/include/asm/kvm_asm.h
@@ -78,6 +78,7 @@ extern char __kvm_hyp_code_end[];
 
 extern void __kvm_flush_vm_context(void);
 extern void __kvm_tlb_flush_vmid_ipa(struct kvm *kvm, phys_addr_t ipa);
+extern void __kvm_tlb_flush_vmid(struct kvm *kvm);
 
 extern int __kvm_vcpu_run(struct kvm_vcpu *vcpu);
 #endif
diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h
index 193ceaf..042206f 100644
--- a/arch/arm/include/asm/kvm_host.h
+++ b/arch/arm/include/asm/kvm_host.h
@@ -230,5 +230,6 @@ int kvm_perf_teardown(void);
 
 u64 kvm_arm_timer_get_reg(struct kvm_vcpu *, u64 regid);
 int kvm_arm_timer_set_reg(struct kvm_vcpu *, u64 regid, u64 value);
+void kvm_arch_flush_remote_tlbs(struct kvm *);
 
 #endif /* __ARM_KVM_HOST_H__ */
diff --git a/arch/arm/kvm/Kconfig b/arch/arm/kvm/Kconfig
index 466bd29..44d3b6f 100644
--- a/arch/arm/kvm/Kconfig
+++ b/arch/arm/kvm/Kconfig
@@ -22,6 +22,7 @@ config KVM
 	select ANON_INODES
 	select HAVE_KVM_CPU_RELAX_INTERCEPT
 	select KVM_MMIO
+	select HAVE_KVM_ARCH_TLB_FLUSH_ALL
 	select KVM_ARM_HOST
 	depends on ARM_VIRT_EXT && ARM_LPAE
 	---help---
diff --git a/arch/arm/kvm/interrupts.S b/arch/arm/kvm/interrupts.S
index 0d68d40..1258d46 100644
--- a/arch/arm/kvm/interrupts.S
+++ b/arch/arm/kvm/interrupts.S
@@ -66,6 +66,18 @@ ENTRY(__kvm_tlb_flush_vmid_ipa)
 	bx	lr
 ENDPROC(__kvm_tlb_flush_vmid_ipa)
 
+/**
+ * void __kvm_tlb_flush_vmid(struct kvm *kvm) - Flush per-VMID TLBs
+ *
+ * Reuses __kvm_tlb_flush_vmid_ipa() for ARMv7, without passing address
+ * parameter
+ */
+
+ENTRY(__kvm_tlb_flush_vmid)
+	b	__kvm_tlb_flush_vmid_ipa
+ENDPROC(__kvm_tlb_flush_vmid)
+
+
 /********************************************************************
  * Flush TLBs and instruction caches of all CPUs inside the inner-shareable
  * domain, for all VMIDs
diff --git a/arch/arm/kvm/mmu.c b/arch/arm/kvm/mmu.c
index 2ac9588..35254c6 100644
--- a/arch/arm/kvm/mmu.c
+++ b/arch/arm/kvm/mmu.c
@@ -56,6 +56,23 @@ static void kvm_tlb_flush_vmid_ipa(struct kvm *kvm, phys_addr_t ipa)
 		kvm_call_hyp(__kvm_tlb_flush_vmid_ipa, kvm, ipa);
 }
 
+#ifdef CONFIG_ARM
+/**
+ * kvm_arch_flush_remote_tlbs() - flush all VM TLB entries
+ * @kvm:       pointer to kvm structure.
+ *
+ * Interface to HYP function to flush all VM TLB entries without address
+ * parameter. In HYP mode reuses __kvm_tlb_flush_vmid_ipa() function used by
+ * kvm_tlb_flush_vmid_ipa().
+ */
+void kvm_arch_flush_remote_tlbs(struct kvm *kvm)
+{
+	if (kvm)
+		kvm_call_hyp(__kvm_tlb_flush_vmid, kvm);
+}
+
+#endif
+
 static int mmu_topup_memory_cache(struct kvm_mmu_memory_cache *cache,
 				  int min, int max)
 {
diff --git a/virt/kvm/Kconfig b/virt/kvm/Kconfig
index 13f2d19..f1efaa5 100644
--- a/virt/kvm/Kconfig
+++ b/virt/kvm/Kconfig
@@ -34,3 +34,6 @@ config HAVE_KVM_CPU_RELAX_INTERCEPT
 
 config KVM_VFIO
        bool
+
+config HAVE_KVM_ARCH_TLB_FLUSH_ALL
+       bool
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index fa70c6e..258f3d9 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -186,12 +186,16 @@ static bool make_all_cpus_request(struct kvm *kvm, unsigned int req)
 
 void kvm_flush_remote_tlbs(struct kvm *kvm)
 {
+#ifdef CONFIG_HAVE_KVM_ARCH_TLB_FLUSH_ALL
+	kvm_arch_flush_remote_tlbs(kvm);
+#else
 	long dirty_count = kvm->tlbs_dirty;
 
 	smp_mb();
 	if (make_all_cpus_request(kvm, KVM_REQ_TLB_FLUSH))
 		++kvm->stat.remote_tlb_flush;
 	cmpxchg(&kvm->tlbs_dirty, dirty_count, 0);
+#endif
 }
 EXPORT_SYMBOL_GPL(kvm_flush_remote_tlbs);
 
-- 
1.7.9.5