From: Steve Capper <Steve.Capper@arm.com>
To: Will Deacon <will@kernel.org>
Cc: Mark Rutland <Mark.Rutland@arm.com>,
Catalin Marinas <Catalin.Marinas@arm.com>,
Geert Uytterhoeven <geert@linux-m68k.org>,
Andrey Konovalov <andreyknvl@google.com>, Qian Cai <cai@lca.pw>,
nd <nd@arm.com>,
"linux-arm-kernel@lists.infradead.org"
<linux-arm-kernel@lists.infradead.org>
Subject: Re: [PATCH 5/8] arm64: memory: Simplify _VA_START and _PAGE_OFFSET definitions
Date: Tue, 13 Aug 2019 18:55:50 +0000 [thread overview]
Message-ID: <20190813185548.GF19835@capper-ampere.manchester.arm.com> (raw)
In-Reply-To: <20190813170149.26037-6-will@kernel.org>
On Tue, Aug 13, 2019 at 06:01:46PM +0100, Will Deacon wrote:
> 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>
Reviewed-by: Steve Capper <steve.capper@arm.com>
> ---
> 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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next prev parent reply other threads:[~2019-08-13 18:56 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 ` [PATCH 5/8] arm64: memory: Simplify _VA_START and _PAGE_OFFSET definitions Will Deacon
2019-08-13 18:55 ` Steve Capper [this message]
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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