[PATCH, RFC 19/62] x86/mm: Handle encrypted memory in page_to_virt() and __pa()

[Kirill A. Shutemov]

Per-KeyID direct mappings require changes into how we find the right
virtual address for a page and virt-to-phys address translations.

page_to_virt() definition overwrites default macros provided by
<linux/mm.h>.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
---
 arch/x86/include/asm/page.h    | 3 +++
 arch/x86/include/asm/page_64.h | 2 +-
 2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/arch/x86/include/asm/page.h b/arch/x86/include/asm/page.h
index 39af59487d5f..aff30554f38e 100644
--- a/arch/x86/include/asm/page.h
+++ b/arch/x86/include/asm/page.h
@@ -72,6 +72,9 @@ static inline void copy_user_page(void *to, void *from, unsigned long vaddr,
 extern bool __virt_addr_valid(unsigned long kaddr);
 #define virt_addr_valid(kaddr)	__virt_addr_valid((unsigned long) (kaddr))
 
+#define page_to_virt(x) \
+	(__va(PFN_PHYS(page_to_pfn(x))) + page_keyid(x) * direct_mapping_size)
+
 #endif	/* __ASSEMBLY__ */
 
 #include <asm-generic/memory_model.h>
diff --git a/arch/x86/include/asm/page_64.h b/arch/x86/include/asm/page_64.h
index f57fc3cc2246..a4f394e3471d 100644
--- a/arch/x86/include/asm/page_64.h
+++ b/arch/x86/include/asm/page_64.h
@@ -24,7 +24,7 @@ static inline unsigned long __phys_addr_nodebug(unsigned long x)
 	/* use the carry flag to determine if x was < __START_KERNEL_map */
 	x = y + ((x > y) ? phys_base : (__START_KERNEL_map - PAGE_OFFSET));
 
-	return x;
+	return x & direct_mapping_mask;
 }
 
 #ifdef CONFIG_DEBUG_VIRTUAL
-- 
2.20.1