arm/arm64: kvm: Use virt_to_idmap instead of virt_to_phys for idmap mappings

KVM initialisation fails on architectures implementing virt_to_idmap()
because virt_to_phys() on such architectures won't fetch you the correct
idmap page.

So update the KVM ARM code to use the virt_to_idmap() to fix the issue.
Since the KVM code is shared between arm and arm64, we create
kvm_virt_to_phys() and handle the redirection in respective headers.

Cc: Christoffer Dall <christoffer.dall@linaro.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>

arch/arm/include/asm/kvm_mmu.h

@@ -140,6 +140,7 @@ static inline void coherent_icache_guest_page(struct kvm *kvm, hva_t hva,
 }
 
 #define kvm_flush_dcache_to_poc(a,l)	__cpuc_flush_dcache_area((a), (l))
+#define kvm_virt_to_phys(x)		virt_to_idmap((unsigned long)(x))
 
 #endif	/* !__ASSEMBLY__ */
 

arch/arm/kvm/mmu.c

@@ -916,9 +916,9 @@ int kvm_mmu_init(void)
 {
 	int err;
 
-	hyp_idmap_start = virt_to_phys(__hyp_idmap_text_start);
-	hyp_idmap_end = virt_to_phys(__hyp_idmap_text_end);
-	hyp_idmap_vector = virt_to_phys(__kvm_hyp_init);
+	hyp_idmap_start = kvm_virt_to_phys(__hyp_idmap_text_start);
+	hyp_idmap_end = kvm_virt_to_phys(__hyp_idmap_text_end);
+	hyp_idmap_vector = kvm_virt_to_phys(__kvm_hyp_init);
 
 	if ((hyp_idmap_start ^ hyp_idmap_end) & PAGE_MASK) {
 		/*
@@ -945,7 +945,7 @@ int kvm_mmu_init(void)
 		 */
 		kvm_flush_dcache_to_poc(init_bounce_page, len);
 
-		phys_base = virt_to_phys(init_bounce_page);
+		phys_base = kvm_virt_to_phys(init_bounce_page);
 		hyp_idmap_vector += phys_base - hyp_idmap_start;
 		hyp_idmap_start = phys_base;
 		hyp_idmap_end = phys_base + len;

arch/arm64/include/asm/kvm_mmu.h

@@ -136,6 +136,7 @@ static inline void coherent_icache_guest_page(struct kvm *kvm, hva_t hva,
 }
 
 #define kvm_flush_dcache_to_poc(a,l)	__flush_dcache_area((a), (l))
+#define kvm_virt_to_phys(x)		__virt_to_phys((unsigned long)(x))
 
 #endif /* __ASSEMBLY__ */
 #endif /* __ARM64_KVM_MMU_H__ */