[PATCH 2/2] arm64: Use simpler arithmetics for the linear map macros

[Catalin Marinas]

Because of the tagged addresses, the __is_lm_address() and
__lm_to_phys() macros grew to some harder to understand bitwise
operations using PAGE_OFFSET. Since these macros only accept untagged
addresses, use a simple subtract operation.

Signed-off-by: Catalin Marinas <catalin.marinas at arm.com>
Cc: Will Deacon <will at kernel.org>
Cc: Ard Biesheuvel <ardb at kernel.org>
Cc: Mark Rutland <mark.rutland at arm.com>
---
 arch/arm64/include/asm/memory.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/include/asm/memory.h b/arch/arm64/include/asm/memory.h
index 3c1aaa522cbd..ff4732785c32 100644
--- a/arch/arm64/include/asm/memory.h
+++ b/arch/arm64/include/asm/memory.h
@@ -251,9 +251,9 @@ static inline const void *__tag_set(const void *addr, u8 tag)
  * lives in the [PAGE_OFFSET, PAGE_END) interval at the bottom of the
  * kernel's TTBR1 address range.
  */
-#define __is_lm_address(addr)	(((u64)(addr) ^ PAGE_OFFSET) < (PAGE_END - PAGE_OFFSET))
+#define __is_lm_address(addr)	(((u64)(addr) - PAGE_OFFSET) < (PAGE_END - PAGE_OFFSET))
 
-#define __lm_to_phys(addr)	(((addr) & ~PAGE_OFFSET) + PHYS_OFFSET)
+#define __lm_to_phys(addr)	(((addr) - PAGE_OFFSET) + PHYS_OFFSET)
 #define __kimg_to_phys(addr)	((addr) - kimage_voffset)
 
 #define __virt_to_phys_nodebug(x) ({					\