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From: Will Deacon <will@kernel.org>
To: linux-arm-kernel@lists.infradead.org
Cc: Mark Rutland <mark.rutland@arm.com>,
	Steve Capper <steve.capper@arm.com>,
	Catalin Marinas <catalin.marinas@arm.com>, Qian Cai <cai@lca.pw>,
	Andrey Konovalov <andreyknvl@google.com>,
	Geert Uytterhoeven <geert@linux-m68k.org>,
	Will Deacon <will@kernel.org>
Subject: [PATCH 5/8] arm64: memory: Simplify _VA_START and _PAGE_OFFSET definitions
Date: Tue, 13 Aug 2019 18:01:46 +0100	[thread overview]
Message-ID: <20190813170149.26037-6-will@kernel.org> (raw)
In-Reply-To: <20190813170149.26037-1-will@kernel.org>

Rather than subtracting from -1 and then adding 1, we can simply
subtract from 0.

Cc: Steve Capper <steve.capper@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
---
 arch/arm64/include/asm/memory.h | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/arch/arm64/include/asm/memory.h b/arch/arm64/include/asm/memory.h
index 56be462c69ce..5552c8cba1e2 100644
--- a/arch/arm64/include/asm/memory.h
+++ b/arch/arm64/include/asm/memory.h
@@ -44,8 +44,7 @@
  * VA_START - the first kernel virtual address.
  */
 #define VA_BITS			(CONFIG_ARM64_VA_BITS)
-#define _PAGE_OFFSET(va)	(UL(0xffffffffffffffff) - \
-					(UL(1) << (va)) + 1)
+#define _PAGE_OFFSET(va)	(-(UL(1) << (va)))
 #define PAGE_OFFSET		(_PAGE_OFFSET(VA_BITS))
 #define KIMAGE_VADDR		(MODULES_END)
 #define BPF_JIT_REGION_START	(KASAN_SHADOW_END)
@@ -63,8 +62,7 @@
 #else
 #define VA_BITS_MIN		(VA_BITS)
 #endif
-#define _VA_START(va)		(UL(0xffffffffffffffff) - \
-				(UL(1) << ((va) - 1)) + 1)
+#define _VA_START(va)		(-(UL(1) << ((va) - 1)))
 
 #define KERNEL_START      _text
 #define KERNEL_END        _end
-- 
2.11.0


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  parent reply	other threads:[~2019-08-13 17:03 UTC|newest]

Thread overview: 44+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-08-13 17:01 [PATCH 0/8] Fix issues with 52-bit kernel virtual addressing Will Deacon
2019-08-13 17:01 ` [PATCH 1/8] arm64: memory: Fix virt_addr_valid() using __is_lm_address() Will Deacon
2019-08-13 18:09   ` Ard Biesheuvel
2019-08-13 19:11     ` Steve Capper
2019-08-13 19:25       ` Ard Biesheuvel
2019-08-13 20:34         ` Steve Capper
2019-08-14 15:17           ` Ard Biesheuvel
2019-08-14  8:32       ` Will Deacon
2019-08-13 18:53   ` Steve Capper
2019-08-14  9:19   ` Catalin Marinas
2019-08-14  9:48     ` Will Deacon
2019-08-14 10:40       ` Catalin Marinas
2019-08-14 12:02         ` Will Deacon
2019-08-13 17:01 ` [PATCH 2/8] arm64: memory: Ensure address tag is masked in conversion macros Will Deacon
2019-08-13 18:54   ` Steve Capper
2019-08-14  9:23   ` Catalin Marinas
2019-08-13 17:01 ` [PATCH 3/8] arm64: memory: Rewrite default page_to_virt()/virt_to_page() Will Deacon
2019-08-13 18:54   ` Steve Capper
2019-08-14  9:30   ` Catalin Marinas
2019-08-14  9:41     ` Will Deacon
2019-08-14 10:56       ` Mark Rutland
2019-08-14 11:17         ` Will Deacon
2019-08-14 11:26           ` Mark Rutland
2019-08-13 17:01 ` [PATCH 4/8] arm64: memory: Simplify virt_to_page() implementation Will Deacon
2019-08-13 18:55   ` Steve Capper
2019-08-14  9:32   ` Catalin Marinas
2019-08-13 17:01 ` Will Deacon [this message]
2019-08-13 18:55   ` [PATCH 5/8] arm64: memory: Simplify _VA_START and _PAGE_OFFSET definitions Steve Capper
2019-08-14  9:33   ` Catalin Marinas
2019-08-14 11:23   ` Mark Rutland
2019-08-14 12:00     ` Will Deacon
2019-08-14 13:18       ` Mark Rutland
2019-08-13 17:01 ` [PATCH 6/8] arm64: memory: Implement __tag_set() as common function Will Deacon
2019-08-13 18:56   ` Steve Capper
2019-08-14  9:34   ` Catalin Marinas
2019-08-13 17:01 ` [PATCH 7/8] arm64: memory: Add comments to end of non-trivial #ifdef blocks Will Deacon
2019-08-13 18:57   ` Steve Capper
2019-08-14  9:35   ` Catalin Marinas
2019-08-13 17:01 ` [PATCH 8/8] arm64: memory: Cosmetic cleanups Will Deacon
2019-08-13 18:57   ` Steve Capper
2019-08-14  9:35   ` Catalin Marinas
2019-08-13 18:53 ` [PATCH 0/8] Fix issues with 52-bit kernel virtual addressing Steve Capper
2019-08-14  8:01 ` Geert Uytterhoeven
2019-08-14 11:29 ` Mark Rutland

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