From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id F325DC43217 for ; Tue, 16 Nov 2021 06:38:22 +0000 (UTC) Received: from vger.kernel.org (unknown [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A08776323A for ; Tue, 16 Nov 2021 06:38:22 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org A08776323A Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234513AbhKPGky (ORCPT ); Tue, 16 Nov 2021 01:40:54 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44244 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234449AbhKPGkj (ORCPT ); Tue, 16 Nov 2021 01:40:39 -0500 Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:e::133]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CC568C061766; Mon, 15 Nov 2021 22:33:07 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=S/CnjLRmgrSJADzeSbJCuEHmdmqJFE1veuDvGJX4T0w=; b=liU1ijFWSLfKahYQGg2gMlonlg Bg7Rint2QOON83r70iUvpcTYk6ZZidEU2FvzFtr2hG9LYfdOceXdjlbOGv8cswIjaWg3CoUBkUgAO lWQReuAm9M/kdt8Iysm3EX/HmxRblzBwnarqHkzV/mVYcpUhS70o/SQFQVOGcsik20hTGpqlkO7ob Y0pToIKtTdiVxsZAnyiDY9DNHiMm41JV3k/b6Gez3tJFTqAQ09y9/wa3zZDLQFgqeKKfr+wYoR0/8 LrKOzfKpwPayVkSNF6m88QTZ5sg9dCybVrgm5i9SgAy40EM+SIE2v1x5CMvM4iPUyHr0BFU5rGViR rRi6yiyA==; Received: from hch by bombadil.infradead.org with local (Exim 4.94.2 #2 (Red Hat Linux)) id 1mms1d-000Qnz-6c; Tue, 16 Nov 2021 06:33:01 +0000 Date: Mon, 15 Nov 2021 22:33:01 -0800 From: Christoph Hellwig To: Matthew Wilcox Cc: Christoph Hellwig , "Darrick J . Wong " , linux-xfs@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-block@vger.kernel.org, Jens Axboe Subject: Re: [PATCH v2 01/28] csky,sparc: Declare flush_dcache_folio() Message-ID: References: <20211108040551.1942823-1-willy@infradead.org> <20211108040551.1942823-2-willy@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Nov 15, 2021 at 03:54:47PM +0000, Matthew Wilcox wrote: > There are three ways to implement flush_dcache_folio(). The first is > as a noop (this is what xtensa does, which is the only architecture > to define ARCH_IMPLEMENTS_FLUSH_DCACHE_FOLIO; it's also done > automatically by asm-generic if the architecture doesn't define > ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE). The second is as a loop which calls > flush_dcache_page() for each page in the folio. That's the default > implementation which you found in mm/util.c. The third way, which I > hope architecture maintainers actually implement, is to just set the > needs-flush bit on the head page. But that requires knowledge of each > architecture; they need to check the needs-flush bit on the head page > instead of the precise page. So I've done the safe, slow thing for > all architectures. The only reason that csky and sparc are "special" > is that they don't include asm-generic/cacheflush.h and the buildbots > didn't catch that before the merge window. > > I'm doing the exact same thing for csky and sparc that I did for > arc/arm/m68k/mips/nds32/nios2/parisc/sh. Nothing more, nothing less. I see how this works no, but it is pretty horrible. Why not something simple like the patch below? If/when an architecture actually wants to override flush_dcache_folio we can find out how to best do it: diff --git a/arch/arc/include/asm/cacheflush.h b/arch/arc/include/asm/cacheflush.h index e8c2c7469e107..e201b4b1655af 100644 --- a/arch/arc/include/asm/cacheflush.h +++ b/arch/arc/include/asm/cacheflush.h @@ -36,7 +36,6 @@ void __flush_dcache_page(phys_addr_t paddr, unsigned long vaddr); #define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1 void flush_dcache_page(struct page *page); -void flush_dcache_folio(struct folio *folio); void dma_cache_wback_inv(phys_addr_t start, unsigned long sz); void dma_cache_inv(phys_addr_t start, unsigned long sz); diff --git a/arch/arm/include/asm/cacheflush.h b/arch/arm/include/asm/cacheflush.h index e68fb879e4f9d..5e56288e343bb 100644 --- a/arch/arm/include/asm/cacheflush.h +++ b/arch/arm/include/asm/cacheflush.h @@ -290,7 +290,6 @@ extern void flush_cache_page(struct vm_area_struct *vma, unsigned long user_addr */ #define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1 extern void flush_dcache_page(struct page *); -void flush_dcache_folio(struct folio *folio); #define ARCH_IMPLEMENTS_FLUSH_KERNEL_VMAP_RANGE 1 static inline void flush_kernel_vmap_range(void *addr, int size) diff --git a/arch/csky/abiv1/inc/abi/cacheflush.h b/arch/csky/abiv1/inc/abi/cacheflush.h index 432aef1f1dc23..ed62e2066ba76 100644 --- a/arch/csky/abiv1/inc/abi/cacheflush.h +++ b/arch/csky/abiv1/inc/abi/cacheflush.h @@ -9,7 +9,6 @@ #define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1 extern void flush_dcache_page(struct page *); -void flush_dcache_folio(struct folio *folio); #define flush_cache_mm(mm) dcache_wbinv_all() #define flush_cache_page(vma, page, pfn) cache_wbinv_all() diff --git a/arch/csky/abiv2/inc/abi/cacheflush.h b/arch/csky/abiv2/inc/abi/cacheflush.h index 7e8bef60958c6..a565e00c3f70b 100644 --- a/arch/csky/abiv2/inc/abi/cacheflush.h +++ b/arch/csky/abiv2/inc/abi/cacheflush.h @@ -25,8 +25,6 @@ static inline void flush_dcache_page(struct page *page) clear_bit(PG_dcache_clean, &page->flags); } -void flush_dcache_folio(struct folio *folio); - #define flush_dcache_mmap_lock(mapping) do { } while (0) #define flush_dcache_mmap_unlock(mapping) do { } while (0) #define flush_icache_page(vma, page) do { } while (0) diff --git a/arch/m68k/include/asm/cacheflush_mm.h b/arch/m68k/include/asm/cacheflush_mm.h index 8ab46625ddd32..1ac55e7b47f01 100644 --- a/arch/m68k/include/asm/cacheflush_mm.h +++ b/arch/m68k/include/asm/cacheflush_mm.h @@ -250,7 +250,6 @@ static inline void __flush_page_to_ram(void *vaddr) #define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1 #define flush_dcache_page(page) __flush_page_to_ram(page_address(page)) -void flush_dcache_folio(struct folio *folio); #define flush_dcache_mmap_lock(mapping) do { } while (0) #define flush_dcache_mmap_unlock(mapping) do { } while (0) #define flush_icache_page(vma, page) __flush_page_to_ram(page_address(page)) diff --git a/arch/mips/include/asm/cacheflush.h b/arch/mips/include/asm/cacheflush.h index f207388541d50..b3dc9c589442a 100644 --- a/arch/mips/include/asm/cacheflush.h +++ b/arch/mips/include/asm/cacheflush.h @@ -61,8 +61,6 @@ static inline void flush_dcache_page(struct page *page) SetPageDcacheDirty(page); } -void flush_dcache_folio(struct folio *folio); - #define flush_dcache_mmap_lock(mapping) do { } while (0) #define flush_dcache_mmap_unlock(mapping) do { } while (0) diff --git a/arch/nds32/include/asm/cacheflush.h b/arch/nds32/include/asm/cacheflush.h index 3fc0bb7d6487c..c2a222ebfa2af 100644 --- a/arch/nds32/include/asm/cacheflush.h +++ b/arch/nds32/include/asm/cacheflush.h @@ -27,7 +27,6 @@ void flush_cache_vunmap(unsigned long start, unsigned long end); #define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1 void flush_dcache_page(struct page *page); -void flush_dcache_folio(struct folio *folio); void copy_to_user_page(struct vm_area_struct *vma, struct page *page, unsigned long vaddr, void *dst, void *src, int len); void copy_from_user_page(struct vm_area_struct *vma, struct page *page, diff --git a/arch/nios2/include/asm/cacheflush.h b/arch/nios2/include/asm/cacheflush.h index 1999561b22aa5..d0b71dd712872 100644 --- a/arch/nios2/include/asm/cacheflush.h +++ b/arch/nios2/include/asm/cacheflush.h @@ -29,7 +29,6 @@ extern void flush_cache_page(struct vm_area_struct *vma, unsigned long vmaddr, unsigned long pfn); #define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1 void flush_dcache_page(struct page *page); -void flush_dcache_folio(struct folio *folio); extern void flush_icache_range(unsigned long start, unsigned long end); extern void flush_icache_page(struct vm_area_struct *vma, struct page *page); diff --git a/arch/parisc/include/asm/cacheflush.h b/arch/parisc/include/asm/cacheflush.h index da0cd4b3a28f2..859b8a34adcfb 100644 --- a/arch/parisc/include/asm/cacheflush.h +++ b/arch/parisc/include/asm/cacheflush.h @@ -50,7 +50,6 @@ void invalidate_kernel_vmap_range(void *vaddr, int size); #define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1 void flush_dcache_page(struct page *page); -void flush_dcache_folio(struct folio *folio); #define flush_dcache_mmap_lock(mapping) xa_lock_irq(&mapping->i_pages) #define flush_dcache_mmap_unlock(mapping) xa_unlock_irq(&mapping->i_pages) diff --git a/arch/sh/include/asm/cacheflush.h b/arch/sh/include/asm/cacheflush.h index c7a97f32432fb..481a664287e2e 100644 --- a/arch/sh/include/asm/cacheflush.h +++ b/arch/sh/include/asm/cacheflush.h @@ -43,7 +43,6 @@ extern void flush_cache_range(struct vm_area_struct *vma, unsigned long start, unsigned long end); #define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1 void flush_dcache_page(struct page *page); -void flush_dcache_folio(struct folio *folio); extern void flush_icache_range(unsigned long start, unsigned long end); #define flush_icache_user_range flush_icache_range extern void flush_icache_page(struct vm_area_struct *vma, diff --git a/arch/sparc/include/asm/cacheflush_32.h b/arch/sparc/include/asm/cacheflush_32.h index 9991c18f4980c..41c6d734a4741 100644 --- a/arch/sparc/include/asm/cacheflush_32.h +++ b/arch/sparc/include/asm/cacheflush_32.h @@ -37,7 +37,6 @@ void sparc_flush_page_to_ram(struct page *page); -void flush_dcache_folio(struct folio *folio); #define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1 #define flush_dcache_page(page) sparc_flush_page_to_ram(page) #define flush_dcache_mmap_lock(mapping) do { } while (0) diff --git a/arch/sparc/include/asm/cacheflush_64.h b/arch/sparc/include/asm/cacheflush_64.h index 9ab59a73c28b1..b9341836597ec 100644 --- a/arch/sparc/include/asm/cacheflush_64.h +++ b/arch/sparc/include/asm/cacheflush_64.h @@ -47,7 +47,6 @@ void flush_dcache_page_all(struct mm_struct *mm, struct page *page); void __flush_dcache_range(unsigned long start, unsigned long end); #define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1 void flush_dcache_page(struct page *page); -void flush_dcache_folio(struct folio *folio); #define flush_icache_page(vma, pg) do { } while(0) diff --git a/arch/xtensa/include/asm/cacheflush.h b/arch/xtensa/include/asm/cacheflush.h index a8a041609c5d0..7b4359312c257 100644 --- a/arch/xtensa/include/asm/cacheflush.h +++ b/arch/xtensa/include/asm/cacheflush.h @@ -121,7 +121,6 @@ void flush_cache_page(struct vm_area_struct*, #define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1 void flush_dcache_page(struct page *); -void flush_dcache_folio(struct folio *); void local_flush_cache_range(struct vm_area_struct *vma, unsigned long start, unsigned long end); @@ -138,9 +137,7 @@ void local_flush_cache_page(struct vm_area_struct *vma, #define flush_cache_vunmap(start,end) do { } while (0) #define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 0 -#define ARCH_IMPLEMENTS_FLUSH_DCACHE_FOLIO #define flush_dcache_page(page) do { } while (0) -static inline void flush_dcache_folio(struct folio *folio) { } #define flush_icache_range local_flush_icache_range #define flush_cache_page(vma, addr, pfn) do { } while (0) diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c index 265c7f8e71342..218df77641802 100644 --- a/fs/iomap/buffered-io.c +++ b/fs/iomap/buffered-io.c @@ -4,6 +4,7 @@ * Copyright (C) 2016-2019 Christoph Hellwig. */ #include +#include #include #include #include @@ -658,6 +659,7 @@ static size_t __iomap_write_end(struct inode *inode, loff_t pos, size_t len, size_t copied, struct folio *folio) { struct iomap_page *iop = to_iomap_page(folio); + flush_dcache_folio(folio); /* diff --git a/include/asm-generic/cacheflush.h b/include/asm-generic/cacheflush.h index fedc0dfa4877c..eeaea7bd97bbf 100644 --- a/include/asm-generic/cacheflush.h +++ b/include/asm-generic/cacheflush.h @@ -49,14 +49,7 @@ static inline void flush_cache_page(struct vm_area_struct *vma, static inline void flush_dcache_page(struct page *page) { } - -static inline void flush_dcache_folio(struct folio *folio) { } #define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 0 -#define ARCH_IMPLEMENTS_FLUSH_DCACHE_FOLIO -#endif - -#ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_FOLIO -void flush_dcache_folio(struct folio *folio); #endif #ifndef flush_dcache_mmap_lock diff --git a/include/linux/cacheflush.h b/include/linux/cacheflush.h new file mode 100644 index 0000000000000..c28359bac8aa5 --- /dev/null +++ b/include/linux/cacheflush.h @@ -0,0 +1,15 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _LINUX_CACHEFLUSH_H +#define _LINUX_CACHEFLUSH_H + +#include + +#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE +void flush_dcache_folio(struct folio *folio); +#else +static inline void flush_dcache_folio(struct folio *folio) +{ +} +#endif /* ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE */ + +#endif /* _LINUX_CACHEFLUSH_H */ diff --git a/mm/util.c b/mm/util.c index e58151a612555..61ffa71adb644 100644 --- a/mm/util.c +++ b/mm/util.c @@ -1090,7 +1090,7 @@ void page_offline_end(void) } EXPORT_SYMBOL(page_offline_end); -#ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_FOLIO +#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE void flush_dcache_folio(struct folio *folio) { long i, nr = folio_nr_pages(folio); @@ -1098,5 +1098,4 @@ void flush_dcache_folio(struct folio *folio) for (i = 0; i < nr; i++) flush_dcache_page(folio_page(folio, i)); } -EXPORT_SYMBOL(flush_dcache_folio); #endif