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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 243C7C433EF for ; Thu, 27 Jan 2022 12:39:06 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 913D86B0071; Thu, 27 Jan 2022 07:39:05 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 8C28D6B0072; Thu, 27 Jan 2022 07:39:05 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 7B1286B0073; Thu, 27 Jan 2022 07:39:05 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0059.hostedemail.com [216.40.44.59]) by kanga.kvack.org (Postfix) with ESMTP id 6CB866B0071 for ; Thu, 27 Jan 2022 07:39:05 -0500 (EST) Received: from smtpin19.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id 2CEDE181251B1 for ; Thu, 27 Jan 2022 12:39:05 +0000 (UTC) X-FDA: 79076021850.19.D66B08A Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by imf16.hostedemail.com (Postfix) with ESMTP id 90C0818000D for ; Thu, 27 Jan 2022 12:39:03 +0000 (UTC) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 1E355618CF; Thu, 27 Jan 2022 12:39:02 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6A9E8C340EA; Thu, 27 Jan 2022 12:38:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1643287141; bh=nP7BCHcZqaThejM5/UQJpmdfSwu/TFysIZsnQzFuZrA=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=SJIDhWJJkUHd9k+b+s4AXsQgC1rbsgyJTErSQr7bDZqIalXWnX8llx0MTv/0HBzaM y4BPl77GLIOGQ8g3805IyG0/MGy/UaiwTdZnbjAUt2sVvEG4JrRB8TQZAueJzWlYIJ 6w6vvQvjpv8LWuRcA+f+OscOxiULj1Mcr//Qujr6ubPXGynWFFFWTRE4oAalwUCPyf TM8uTHSIQzLStkH2haO4Z0zJyNSkHVh2YT6QrAqk/+w4qsLALuMyb7c8fm1Rlyospv IKN2qJNyplnFvO8PNZJTwW1oTAHitUSVDgeaaTw/skhCNN5Vwybqo0e5nusPOgSAdl jthrgwgv0ao9A== Date: Thu, 27 Jan 2022 14:38:53 +0200 From: Mike Rapoport To: Anshuman Khandual Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, hch@infradead.org, akpm@linux-foundation.org Subject: Re: [RFC V1 00/31] mm/mmap: Drop protection_map[] and platform's __SXXX/__PXXX requirements Message-ID: References: <1643029028-12710-1-git-send-email-anshuman.khandual@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1643029028-12710-1-git-send-email-anshuman.khandual@arm.com> Authentication-Results: imf16.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=SJIDhWJJ; spf=pass (imf16.hostedemail.com: domain of rppt@kernel.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=rppt@kernel.org; dmarc=pass (policy=none) header.from=kernel.org X-Rspam-User: nil X-Rspamd-Queue-Id: 90C0818000D X-Stat-Signature: 6fwfzt5bcsi1oqtz8pyfs594pieur7fi X-Rspamd-Server: rspam12 X-HE-Tag: 1643287143-238942 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: Hi Anshuman, On Mon, Jan 24, 2022 at 06:26:37PM +0530, Anshuman Khandual wrote: > protection_map[] is an array based construct that translates given vm_flags > combination. This array contains page protection map, which is populated by > the platform via [__S000 .. __S111] and [__P000 .. __P111] exported macros. > Primary usage for protection_map[] is for vm_get_page_prot(), which is used > to determine page protection value for a given vm_flags. vm_get_page_prot() > implementation, could again call platform overrides arch_vm_get_page_prot() > and arch_filter_pgprot(). Some platforms override protection_map[] that was > originally built with __SXXX/__PXXX with different runtime values. > > Currently there are multiple layers of abstraction i.e __SXXX/__PXXX macros > , protection_map[], arch_vm_get_page_prot() and arch_filter_pgprot() built > between the platform and generic MM, finally defining vm_get_page_prot(). > > Hence this series proposes to drop all these abstraction levels and instead > just move the responsibility of defining vm_get_page_prot() to the platform > itself making it clean and simple. > > This first introduces ARCH_HAS_VM_GET_PAGE_PROT which enables the platforms > to define custom vm_get_page_prot(). This starts converting platforms that > either change protection_map[] or define the overrides arch_filter_pgprot() > or arch_vm_get_page_prot() which enables for those constructs to be dropped > off completely. This series then converts remaining platforms which enables > for __SXXX/__PXXX constructs to be dropped off completely. Finally it drops > the generic vm_get_page_prot() and then ARCH_HAS_VM_GET_PAGE_PROT as every > platform now defines their own vm_get_page_prot(). I generally like the idea, I just think the conversion can be more straight forward. Rather than adding ARCH_HAS_VM_GET_PAGE_PROT and then dropping it, why won't me make the generic vm_get_page_prot() __weak, then add per-arch implementation and in the end drop the generic one? > The last patch demonstrates how vm_flags combination indices can be defined > as macros and be replaces across all platforms (if required, not done yet). > > The series has been inspired from an earlier discuss with Christoph Hellwig > > https://lore.kernel.org/all/1632712920-8171-1-git-send-email-anshuman.khandual@arm.com/ > > This series applies on 5.17-rc1 after the following patch. > > https://lore.kernel.org/all/1643004823-16441-1-git-send-email-anshuman.khandual@arm.com/ > > This has been cross built for multiple platforms. I would like to get some > early feed back on this proposal. All reviews and suggestions welcome. > > Hello Christoph, > > I have taken the liberty to preserve your authorship on the x86 patch which > is borrowed almost as is from our earlier discussion. I have also added you > as 'Suggested-by:' on the patch that adds config ARCH_HAS_VM_GET_PAGE_PROT. > Nonetheless please feel free to correct me for any other missing authorship > attributes I should have added. Thank you. > > - Anshuman > > Cc: Christoph Hellwig > Cc: Andrew Morton > Cc: linux-mm@kvack.org > Cc: linux-kernel@vger.kernel.org > > Anshuman Khandual (30): > mm/debug_vm_pgtable: Directly use vm_get_page_prot() > mm/mmap: Clarify protection_map[] indices > mm/mmap: Add new config ARCH_HAS_VM_GET_PAGE_PROT > powerpc/mm: Enable ARCH_HAS_VM_GET_PAGE_PROT > arm64/mm: Enable ARCH_HAS_VM_GET_PAGE_PROT > sparc/mm: Enable ARCH_HAS_VM_GET_PAGE_PROT > mips/mm: Enable ARCH_HAS_VM_GET_PAGE_PROT > m68k/mm: Enable ARCH_HAS_VM_GET_PAGE_PROT > arm/mm: Enable ARCH_HAS_VM_GET_PAGE_PROT > mm/mmap: Drop protection_map[] > mm/mmap: Drop arch_filter_pgprot() > mm/mmap: Drop arch_vm_get_page_pgprot() > s390/mm: Enable ARCH_HAS_VM_GET_PAGE_PROT > riscv/mm: Enable ARCH_HAS_VM_GET_PAGE_PROT > alpha/mm: Enable ARCH_HAS_VM_GET_PAGE_PROT > sh/mm: Enable ARCH_HAS_VM_GET_PAGE_PROT > arc/mm: Enable ARCH_HAS_VM_GET_PAGE_PROT > csky/mm: Enable ARCH_HAS_VM_GET_PAGE_PROT > extensa/mm: Enable ARCH_HAS_VM_GET_PAGE_PROT > parisc/mm: Enable ARCH_HAS_VM_GET_PAGE_PROT > openrisc/mm: Enable ARCH_HAS_VM_GET_PAGE_PROT > um/mm: Enable ARCH_HAS_VM_GET_PAGE_PROT > microblaze/mm: Enable ARCH_HAS_VM_GET_PAGE_PROT > nios2/mm: Enable ARCH_HAS_VM_GET_PAGE_PROT > hexagon/mm: Enable ARCH_HAS_VM_GET_PAGE_PROT > nds32/mm: Enable ARCH_HAS_VM_GET_PAGE_PROT > ia64/mm: Enable ARCH_HAS_VM_GET_PAGE_PROT > mm/mmap: Drop generic vm_get_page_prot() > mm/mmap: Drop ARCH_HAS_VM_GET_PAGE_PROT > mm/mmap: Define macros for vm_flags access permission combinations > > Christoph Hellwig (1): > x86/mm: Enable ARCH_HAS_VM_GET_PAGE_PROT > > arch/alpha/include/asm/pgtable.h | 17 ----- > arch/alpha/mm/init.c | 41 +++++++++++ > arch/arc/include/asm/pgtable-bits-arcv2.h | 17 ----- > arch/arc/mm/mmap.c | 41 +++++++++++ > arch/arm/include/asm/pgtable.h | 18 ----- > arch/arm/mm/mmu.c | 50 +++++++++++-- > arch/arm64/Kconfig | 1 - > arch/arm64/include/asm/mman.h | 3 +- > arch/arm64/include/asm/pgtable-prot.h | 18 ----- > arch/arm64/include/asm/pgtable.h | 2 +- > arch/arm64/mm/mmap.c | 50 +++++++++++++ > arch/csky/include/asm/pgtable.h | 18 ----- > arch/csky/mm/init.c | 41 +++++++++++ > arch/hexagon/include/asm/pgtable.h | 24 ------- > arch/hexagon/mm/init.c | 42 +++++++++++ > arch/ia64/include/asm/pgtable.h | 17 ----- > arch/ia64/mm/init.c | 43 ++++++++++- > arch/m68k/include/asm/mcf_pgtable.h | 59 --------------- > arch/m68k/include/asm/motorola_pgtable.h | 22 ------ > arch/m68k/include/asm/sun3_pgtable.h | 22 ------ > arch/m68k/mm/init.c | 87 +++++++++++++++++++++++ > arch/m68k/mm/motorola.c | 44 +++++++++++- > arch/microblaze/include/asm/pgtable.h | 17 ----- > arch/microblaze/mm/init.c | 41 +++++++++++ > arch/mips/include/asm/pgtable.h | 22 ------ > arch/mips/mm/cache.c | 65 ++++++++++------- > arch/nds32/include/asm/pgtable.h | 17 ----- > arch/nds32/mm/mmap.c | 41 +++++++++++ > arch/nios2/include/asm/pgtable.h | 16 ----- > arch/nios2/mm/init.c | 41 +++++++++++ > arch/openrisc/include/asm/pgtable.h | 18 ----- > arch/openrisc/mm/init.c | 41 +++++++++++ > arch/parisc/include/asm/pgtable.h | 20 ------ > arch/parisc/mm/init.c | 41 +++++++++++ > arch/powerpc/include/asm/mman.h | 3 +- > arch/powerpc/include/asm/pgtable.h | 19 ----- > arch/powerpc/mm/mmap.c | 47 ++++++++++++ > arch/riscv/include/asm/pgtable.h | 16 ----- > arch/riscv/mm/init.c | 41 +++++++++++ > arch/s390/include/asm/pgtable.h | 17 ----- > arch/s390/mm/mmap.c | 41 +++++++++++ > arch/sh/include/asm/pgtable.h | 17 ----- > arch/sh/mm/mmap.c | 43 +++++++++++ > arch/sparc/include/asm/mman.h | 1 - > arch/sparc/include/asm/pgtable_32.h | 19 ----- > arch/sparc/include/asm/pgtable_64.h | 19 ----- > arch/sparc/mm/init_32.c | 41 +++++++++++ > arch/sparc/mm/init_64.c | 71 +++++++++++++----- > arch/um/include/asm/pgtable.h | 17 ----- > arch/um/kernel/mem.c | 41 +++++++++++ > arch/x86/Kconfig | 1 - > arch/x86/include/asm/pgtable.h | 5 -- > arch/x86/include/asm/pgtable_types.h | 19 ----- > arch/x86/include/uapi/asm/mman.h | 14 ---- > arch/x86/mm/Makefile | 2 +- > arch/x86/mm/mem_encrypt_amd.c | 4 -- > arch/x86/mm/pgprot.c | 71 ++++++++++++++++++ > arch/xtensa/include/asm/pgtable.h | 18 ----- > arch/xtensa/mm/init.c | 41 +++++++++++ > include/linux/mm.h | 45 ++++++++++-- > include/linux/mman.h | 4 -- > mm/Kconfig | 3 - > mm/debug_vm_pgtable.c | 27 +++---- > mm/mmap.c | 22 ------ > 64 files changed, 1150 insertions(+), 636 deletions(-) > create mode 100644 arch/x86/mm/pgprot.c > > -- > 2.25.1 > > -- Sincerely yours, Mike.