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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 03C56C3DA5D for ; Thu, 25 Jul 2024 15:50:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=ArRLjz7MM7fiGV8xlWJWM7vHjOZhJqcW4vU/tEb+ShU=; b=NFqHdylOZ71ZtbaIsz6ZIvH+7d xCM8N/u6BW4TDSU+/GQBKoiEbHPWYe0BvCFFJEjPbv2dom9uuanNkHPGctGvsML0ei8JdsnSckRkD f0maBfk+A3P5rEcdiR9Wt/FgWxGKxp5Laa93XcG5+jYD0K2/mBXUqH93Zno684scTZaX/JhPpBITW oqvw2lCfrYqykS7nt2iJSw5PRo8Ut6Zqd3IkveOKTLQfZQntbAhP4NtY543t+5gL1ZUY2m0D5p4I9 zQf8HWLa44KDshFu+3sjHND5vBiLxqJkayNsr8+Wh5kjYdGsNcQTUDI1YOBwB0icA6TuJn+mLTGN2 pXc8ZHgQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1sX0jX-00000001TjW-2GVP; Thu, 25 Jul 2024 15:50:23 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1sX0j8-00000001Tbz-0v0Q for linux-arm-kernel@lists.infradead.org; Thu, 25 Jul 2024 15:49:59 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id C05D41476; Thu, 25 Jul 2024 08:50:22 -0700 (PDT) Received: from e133380.arm.com (e133380.arm.com [10.1.197.55]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 8FEB03F5A1; Thu, 25 Jul 2024 08:49:53 -0700 (PDT) Date: Thu, 25 Jul 2024 16:49:50 +0100 From: Dave Martin To: Joey Gouly Cc: linux-arm-kernel@lists.infradead.org, akpm@linux-foundation.org, aneesh.kumar@kernel.org, aneesh.kumar@linux.ibm.com, bp@alien8.de, broonie@kernel.org, catalin.marinas@arm.com, christophe.leroy@csgroup.eu, dave.hansen@linux.intel.com, hpa@zytor.com, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linuxppc-dev@lists.ozlabs.org, maz@kernel.org, mingo@redhat.com, mpe@ellerman.id.au, naveen.n.rao@linux.ibm.com, npiggin@gmail.com, oliver.upton@linux.dev, shuah@kernel.org, szabolcs.nagy@arm.com, tglx@linutronix.de, will@kernel.org, x86@kernel.org, kvmarm@lists.linux.dev Subject: Re: [PATCH v4 13/29] arm64: convert protection key into vm_flags and pgprot values Message-ID: References: <20240503130147.1154804-1-joey.gouly@arm.com> <20240503130147.1154804-14-joey.gouly@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240503130147.1154804-14-joey.gouly@arm.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240725_084958_323476_453D4969 X-CRM114-Status: GOOD ( 19.01 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Fri, May 03, 2024 at 02:01:31PM +0100, Joey Gouly wrote: > Modify arch_calc_vm_prot_bits() and vm_get_page_prot() such that the pkey > value is set in the vm_flags and then into the pgprot value. > > Signed-off-by: Joey Gouly > Cc: Catalin Marinas > Cc: Will Deacon > --- > arch/arm64/include/asm/mman.h | 8 +++++++- > arch/arm64/mm/mmap.c | 9 +++++++++ > 2 files changed, 16 insertions(+), 1 deletion(-) > > diff --git a/arch/arm64/include/asm/mman.h b/arch/arm64/include/asm/mman.h > index 5966ee4a6154..ecb2d18dc4d7 100644 > --- a/arch/arm64/include/asm/mman.h > +++ b/arch/arm64/include/asm/mman.h > @@ -7,7 +7,7 @@ > #include > > static inline unsigned long arch_calc_vm_prot_bits(unsigned long prot, > - unsigned long pkey __always_unused) > + unsigned long pkey) > { > unsigned long ret = 0; > > @@ -17,6 +17,12 @@ static inline unsigned long arch_calc_vm_prot_bits(unsigned long prot, > if (system_supports_mte() && (prot & PROT_MTE)) > ret |= VM_MTE; > > +#if defined(CONFIG_ARCH_HAS_PKEYS) > + ret |= pkey & 0x1 ? VM_PKEY_BIT0 : 0; > + ret |= pkey & 0x2 ? VM_PKEY_BIT1 : 0; > + ret |= pkey & 0x4 ? VM_PKEY_BIT2 : 0; Out of interest, is this as bad as it looks or does the compiler turn it into a shift and mask? > +#endif > + > return ret; > } > #define arch_calc_vm_prot_bits(prot, pkey) arch_calc_vm_prot_bits(prot, pkey) > diff --git a/arch/arm64/mm/mmap.c b/arch/arm64/mm/mmap.c > index 642bdf908b22..86eda6bc7893 100644 > --- a/arch/arm64/mm/mmap.c > +++ b/arch/arm64/mm/mmap.c > @@ -102,6 +102,15 @@ pgprot_t vm_get_page_prot(unsigned long vm_flags) > if (vm_flags & VM_MTE) > prot |= PTE_ATTRINDX(MT_NORMAL_TAGGED); > > +#ifdef CONFIG_ARCH_HAS_PKEYS > + if (vm_flags & VM_PKEY_BIT0) > + prot |= PTE_PO_IDX_0; > + if (vm_flags & VM_PKEY_BIT1) > + prot |= PTE_PO_IDX_1; > + if (vm_flags & VM_PKEY_BIT2) > + prot |= PTE_PO_IDX_2; > +#endif > + Ditto. At least we only have three bits to cope with either way. I'm guessing that these functions are not super-hot path. [...] Cheers ---Dave