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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 955F2C433EF for ; Fri, 8 Apr 2022 10:28:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233404AbiDHKaZ (ORCPT ); Fri, 8 Apr 2022 06:30:25 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46190 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229663AbiDHKaX (ORCPT ); Fri, 8 Apr 2022 06:30:23 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7F919319A1C; Fri, 8 Apr 2022 03:28:19 -0700 (PDT) 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 ams.source.kernel.org (Postfix) with ESMTPS id 1D68CB82A1E; Fri, 8 Apr 2022 10:28:18 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id CDA71C385A1; Fri, 8 Apr 2022 10:28:14 +0000 (UTC) Date: Fri, 8 Apr 2022 11:28:11 +0100 From: Catalin Marinas To: Anshuman Khandual Cc: linux-mm@kvack.org, akpm@linux-foundation.org, Christoph Hellwig , linuxppc-dev@lists.ozlabs.org, linux-arm-kernel@lists.infradead.org, sparclinux@vger.kernel.org, linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org, Will Deacon Subject: Re: [PATCH V4 3/7] arm64/mm: Enable ARCH_HAS_VM_GET_PAGE_PROT Message-ID: References: <20220407103251.1209606-1-anshuman.khandual@arm.com> <20220407103251.1209606-4-anshuman.khandual@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220407103251.1209606-4-anshuman.khandual@arm.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Apr 07, 2022 at 04:02:47PM +0530, Anshuman Khandual wrote: > diff --git a/arch/arm64/mm/mmap.c b/arch/arm64/mm/mmap.c > index 77ada00280d9..307534fcec00 100644 > --- a/arch/arm64/mm/mmap.c > +++ b/arch/arm64/mm/mmap.c > @@ -55,3 +55,36 @@ static int __init adjust_protection_map(void) > return 0; > } > arch_initcall(adjust_protection_map); > + > +static pgprot_t arm64_arch_vm_get_page_prot(unsigned long vm_flags) > +{ > + pteval_t prot = 0; > + > + if (vm_flags & VM_ARM64_BTI) > + prot |= PTE_GP; > + > + /* > + * There are two conditions required for returning a Normal Tagged > + * memory type: (1) the user requested it via PROT_MTE passed to > + * mmap() or mprotect() and (2) the corresponding vma supports MTE. We > + * register (1) as VM_MTE in the vma->vm_flags and (2) as > + * VM_MTE_ALLOWED. Note that the latter can only be set during the > + * mmap() call since mprotect() does not accept MAP_* flags. > + * Checking for VM_MTE only is sufficient since arch_validate_flags() > + * does not permit (VM_MTE & !VM_MTE_ALLOWED). > + */ > + if (vm_flags & VM_MTE) > + prot |= PTE_ATTRINDX(MT_NORMAL_TAGGED); > + > + return __pgprot(prot); > +} > + > +pgprot_t vm_get_page_prot(unsigned long vm_flags) > +{ > + pgprot_t ret = __pgprot(pgprot_val(protection_map[vm_flags & > + (VM_READ|VM_WRITE|VM_EXEC|VM_SHARED)]) | > + pgprot_val(arm64_arch_vm_get_page_prot(vm_flags))); > + > + return ret; > +} > +EXPORT_SYMBOL(vm_get_page_prot); Could you write all this in a single function? I think I mentioned it in a previous series (untested): pgprot_t vm_get_page_prot(unsigned long vm_flags) { pteval_t prot = pgprot_val(protection_map[vm_flags & (VM_READ|VM_WRITE|VM_EXEC|VM_SHARED)]); if (vm_flags & VM_ARM64_BTI) prot |= PTE_GP; /* * There are two conditions required for returning a Normal Tagged * memory type: (1) the user requested it via PROT_MTE passed to * mmap() or mprotect() and (2) the corresponding vma supports MTE. We * register (1) as VM_MTE in the vma->vm_flags and (2) as * VM_MTE_ALLOWED. Note that the latter can only be set during the * mmap() call since mprotect() does not accept MAP_* flags. * Checking for VM_MTE only is sufficient since arch_validate_flags() * does not permit (VM_MTE & !VM_MTE_ALLOWED). */ if (vm_flags & VM_MTE) prot |= PTE_ATTRINDX(MT_NORMAL_TAGGED); return __pgprot(prot); } EXPORT_SYMBOL(vm_get_page_prot); With that: Reviewed-by: Catalin Marinas