From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-it1-f197.google.com (mail-it1-f197.google.com [209.85.166.197]) by kanga.kvack.org (Postfix) with ESMTP id CF7646B0531 for ; Wed, 7 Nov 2018 12:39:06 -0500 (EST) Received: by mail-it1-f197.google.com with SMTP id r79-v6so11358970itc.4 for ; Wed, 07 Nov 2018 09:39:06 -0800 (PST) Received: from ale.deltatee.com (ale.deltatee.com. [207.54.116.67]) by mx.google.com with ESMTPS id c7-v6si924267jah.125.2018.11.07.09.39.03 for (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Wed, 07 Nov 2018 09:39:03 -0800 (PST) From: Logan Gunthorpe Date: Wed, 7 Nov 2018 10:38:58 -0700 Message-Id: <20181107173859.24096-2-logang@deltatee.com> In-Reply-To: <20181107173859.24096-1-logang@deltatee.com> References: <20181107173859.24096-1-logang@deltatee.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Subject: [PATCH 1/2] mm: Introduce common STRUCT_PAGE_MAX_SHIFT define Sender: owner-linux-mm@kvack.org List-ID: To: linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-arch@vger.kernel.org, linux-riscv@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-sh@vger.kernel.org, Andrew Morton Cc: Stephen Bates , Palmer Dabbelt , Albert Ou , Christoph Hellwig , Arnd Bergmann , Logan Gunthorpe , Catalin Marinas This define is used by arm64 to calculate the size of the vmemmap region. It is defined as the log2 of the upper bound on the size of a struct page. We move it into mm_types.h so it can be defined properly instead of set and checked with a build bug. This also allows us to use the same define for riscv. Signed-off-by: Logan Gunthorpe Acked-by: Will Deacon Cc: Catalin Marinas Cc: Arnd Bergmann Cc: Andrew Morton Cc: Christoph Hellwig --- arch/arm64/include/asm/memory.h | 9 --------- arch/arm64/mm/init.c | 8 -------- include/asm-generic/fixmap.h | 1 + include/linux/mm_types.h | 5 +++++ 4 files changed, 6 insertions(+), 17 deletions(-) diff --git a/arch/arm64/include/asm/memory.h b/arch/arm64/include/asm/memory.h index b96442960aea..f0a5c9531e8b 100644 --- a/arch/arm64/include/asm/memory.h +++ b/arch/arm64/include/asm/memory.h @@ -34,15 +34,6 @@ */ #define PCI_IO_SIZE SZ_16M -/* - * Log2 of the upper bound of the size of a struct page. Used for sizing - * the vmemmap region only, does not affect actual memory footprint. - * We don't use sizeof(struct page) directly since taking its size here - * requires its definition to be available at this point in the inclusion - * chain, and it may not be a power of 2 in the first place. - */ -#define STRUCT_PAGE_MAX_SHIFT 6 - /* * VMEMMAP_SIZE - allows the whole linear region to be covered by * a struct page array diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c index 9d9582cac6c4..1a3e411a1d08 100644 --- a/arch/arm64/mm/init.c +++ b/arch/arm64/mm/init.c @@ -612,14 +612,6 @@ void __init mem_init(void) BUILD_BUG_ON(TASK_SIZE_32 > TASK_SIZE_64); #endif -#ifdef CONFIG_SPARSEMEM_VMEMMAP - /* - * Make sure we chose the upper bound of sizeof(struct page) - * correctly when sizing the VMEMMAP array. - */ - BUILD_BUG_ON(sizeof(struct page) > (1 << STRUCT_PAGE_MAX_SHIFT)); -#endif - if (PAGE_SIZE >= 16384 && get_num_physpages() <= 128) { extern int sysctl_overcommit_memory; /* diff --git a/include/asm-generic/fixmap.h b/include/asm-generic/fixmap.h index 827e4d3bbc7a..8cc7b09c1bc7 100644 --- a/include/asm-generic/fixmap.h +++ b/include/asm-generic/fixmap.h @@ -16,6 +16,7 @@ #define __ASM_GENERIC_FIXMAP_H #include +#include #define __fix_to_virt(x) (FIXADDR_TOP - ((x) << PAGE_SHIFT)) #define __virt_to_fix(x) ((FIXADDR_TOP - ((x)&PAGE_MASK)) >> PAGE_SHIFT) diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h index 5ed8f6292a53..2c471a2c43fa 100644 --- a/include/linux/mm_types.h +++ b/include/linux/mm_types.h @@ -206,6 +206,11 @@ struct page { #endif } _struct_page_alignment; +/* + * Used for sizing the vmemmap region on some architectures + */ +#define STRUCT_PAGE_MAX_SHIFT (order_base_2(sizeof(struct page))) + #define PAGE_FRAG_CACHE_MAX_SIZE __ALIGN_MASK(32768, ~PAGE_MASK) #define PAGE_FRAG_CACHE_MAX_ORDER get_order(PAGE_FRAG_CACHE_MAX_SIZE) -- 2.19.0