From: Will Deacon <will@kernel.org>
To: Mark Rutland <mark.rutland@arm.com>
Cc: Steve Capper <steve.capper@arm.com>,
Andrey Konovalov <andreyknvl@google.com>,
Geert Uytterhoeven <geert@linux-m68k.org>,
Catalin Marinas <catalin.marinas@arm.com>, Qian Cai <cai@lca.pw>,
linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH 3/8] arm64: memory: Rewrite default page_to_virt()/virt_to_page()
Date: Wed, 14 Aug 2019 12:17:22 +0100 [thread overview]
Message-ID: <20190814111722.r5xomirfanmxcor6@willie-the-truck> (raw)
In-Reply-To: <20190814105638.GA17931@lakrids.cambridge.arm.com>
On Wed, Aug 14, 2019 at 11:56:39AM +0100, Mark Rutland wrote:
> On Wed, Aug 14, 2019 at 10:41:19AM +0100, Will Deacon wrote:
> > On Wed, Aug 14, 2019 at 10:30:19AM +0100, Catalin Marinas wrote:
> > > On Tue, Aug 13, 2019 at 06:01:44PM +0100, Will Deacon wrote:
> > > > diff --git a/arch/arm64/include/asm/memory.h b/arch/arm64/include/asm/memory.h
> > > > index 47b4dc73b8bf..77074b3a1025 100644
> > > > --- a/arch/arm64/include/asm/memory.h
> > > > +++ b/arch/arm64/include/asm/memory.h
> > > > @@ -313,19 +313,18 @@ static inline void *phys_to_virt(phys_addr_t x)
> > > > #if !defined(CONFIG_SPARSEMEM_VMEMMAP) || defined(CONFIG_DEBUG_VIRTUAL)
> > > > #define virt_to_page(kaddr) pfn_to_page(__pa(kaddr) >> PAGE_SHIFT)
> > > > #else
> > > > -#define __virt_to_pgoff(kaddr) (((u64)(kaddr) - PAGE_OFFSET) / PAGE_SIZE * sizeof(struct page))
> > > > -#define __page_to_voff(kaddr) (((u64)(kaddr) - VMEMMAP_START) * PAGE_SIZE / sizeof(struct page))
> > > > -
> > > > -#define page_to_virt(page) ({ \
> > > > - unsigned long __addr = \
> > > > - ((__page_to_voff(page)) + PAGE_OFFSET); \
> > > > - const void *__addr_tag = \
> > > > - __tag_set((void *)__addr, page_kasan_tag(page)); \
> > > > - ((void *)__addr_tag); \
> > > > +#define page_to_virt(x) ({ \
> > > > + __typeof__(x) __page = x; \
> > >
> > > Why not struct page * directly here?
> >
> > I started out with that, but then you have to deal with const struct page *
> > as well and it gets pretty messy.
>
> What goes wrong if you always use const struct page *__page?
It would probably work, but then I wondered about the possibility of
volatile and decided that __typeof__ was cleaner.
Will
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next prev parent reply other threads:[~2019-08-14 11:17 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 [this message]
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
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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