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charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org 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 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel