[PATCH v2 2/7] KVM: arm64: Add FEAT_TLBIRANGE support

[Raghavendra Rao Ananta]

Define a generic function __kvm_tlb_flush_range() to
invalidate the TLBs over a range of addresses. The
implementation accepts 'op' as a generic TLBI operation.
Upcoming patches will use this to implement IPA based
TLB invalidations (ipas2e1is).

If the system doesn't support FEAT_TLBIRANGE, the
implementation falls back to flushing the pages one by one
for the range supplied.

Signed-off-by: Raghavendra Rao Ananta <rananta at google.com>
---
 arch/arm64/include/asm/kvm_asm.h | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/arch/arm64/include/asm/kvm_asm.h b/arch/arm64/include/asm/kvm_asm.h
index 43c3bc0f9544d..995ff048e8851 100644
--- a/arch/arm64/include/asm/kvm_asm.h
+++ b/arch/arm64/include/asm/kvm_asm.h
@@ -221,6 +221,24 @@ DECLARE_KVM_NVHE_SYM(__per_cpu_end);
 DECLARE_KVM_HYP_SYM(__bp_harden_hyp_vecs);
 #define __bp_harden_hyp_vecs	CHOOSE_HYP_SYM(__bp_harden_hyp_vecs)
 
+#define __kvm_tlb_flush_range(op, mmu, start, end, level, tlb_level) do {	\
+	unsigned long pages, stride;						\
+										\
+	stride = kvm_granule_size(level);					\
+	start = round_down(start, stride);					\
+	end = round_up(end, stride);						\
+	pages = (end - start) >> PAGE_SHIFT;					\
+										\
+	if ((!system_supports_tlb_range() &&					\
+	     (end - start) >= (MAX_TLBI_OPS * stride)) ||			\
+	    pages >= MAX_TLBI_RANGE_PAGES) {					\
+		__kvm_tlb_flush_vmid(mmu);					\
+		break;								\
+	}									\
+										\
+	__flush_tlb_range_op(op, start, pages, stride, 0, tlb_level, false);	\
+} while (0)
+
 extern void __kvm_flush_vm_context(void);
 extern void __kvm_flush_cpu_context(struct kvm_s2_mmu *mmu);
 extern void __kvm_tlb_flush_vmid_ipa(struct kvm_s2_mmu *mmu, phys_addr_t ipa,
-- 
2.39.1.519.gcb327c4b5f-goog