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 47001C433F5 for ; Wed, 13 Apr 2022 04:04:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232233AbiDMEGo (ORCPT ); Wed, 13 Apr 2022 00:06:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39612 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230454AbiDMEGm (ORCPT ); Wed, 13 Apr 2022 00:06:42 -0400 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 62B7C4EF6F; Tue, 12 Apr 2022 21:04:14 -0700 (PDT) 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 2791A13D5; Tue, 12 Apr 2022 21:04:14 -0700 (PDT) Received: from [10.163.39.141] (unknown [10.163.39.141]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 9FE6B3F73B; Tue, 12 Apr 2022 21:04:09 -0700 (PDT) Message-ID: <78d9bb56-19ae-ea00-cb66-8d1f4baf4f68@arm.com> Date: Wed, 13 Apr 2022 09:34:46 +0530 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.5.0 Subject: Re: [PATCH V5 2/7] powerpc/mm: Enable ARCH_HAS_VM_GET_PAGE_PROT Content-Language: en-US To: Christophe Leroy , "linux-mm@kvack.org" , "akpm@linux-foundation.org" Cc: "catalin.marinas@arm.com" , 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" , Michael Ellerman , Paul Mackerras References: <20220412043848.80464-1-anshuman.khandual@arm.com> <20220412043848.80464-3-anshuman.khandual@arm.com> From: Anshuman Khandual In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 4/12/22 17:57, Christophe Leroy wrote: > > > Le 12/04/2022 à 06:38, Anshuman Khandual a écrit : >> This defines and exports a platform specific custom vm_get_page_prot() via >> subscribing ARCH_HAS_VM_GET_PAGE_PROT. While here, this also localizes >> arch_vm_get_page_prot() as __vm_get_page_prot() and moves it near >> vm_get_page_prot(). >> >> Cc: Michael Ellerman >> Cc: Paul Mackerras >> Cc: linuxppc-dev@lists.ozlabs.org >> Cc: linux-kernel@vger.kernel.org >> Signed-off-by: Anshuman Khandual >> --- >> arch/powerpc/Kconfig | 1 + >> arch/powerpc/include/asm/mman.h | 12 ------------ >> arch/powerpc/mm/book3s64/pgtable.c | 20 ++++++++++++++++++++ >> 3 files changed, 21 insertions(+), 12 deletions(-) >> >> diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig >> index 174edabb74fa..69e44358a235 100644 >> --- a/arch/powerpc/Kconfig >> +++ b/arch/powerpc/Kconfig >> @@ -140,6 +140,7 @@ config PPC >> select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST >> select ARCH_HAS_UACCESS_FLUSHCACHE >> select ARCH_HAS_UBSAN_SANITIZE_ALL >> + select ARCH_HAS_VM_GET_PAGE_PROT if PPC_BOOK3S_64 >> select ARCH_HAVE_NMI_SAFE_CMPXCHG >> select ARCH_KEEP_MEMBLOCK >> select ARCH_MIGHT_HAVE_PC_PARPORT >> diff --git a/arch/powerpc/include/asm/mman.h b/arch/powerpc/include/asm/mman.h >> index 7cb6d18f5cd6..1b024e64c8ec 100644 >> --- a/arch/powerpc/include/asm/mman.h >> +++ b/arch/powerpc/include/asm/mman.h >> @@ -24,18 +24,6 @@ static inline unsigned long arch_calc_vm_prot_bits(unsigned long prot, >> } >> #define arch_calc_vm_prot_bits(prot, pkey) arch_calc_vm_prot_bits(prot, pkey) >> >> -static inline pgprot_t arch_vm_get_page_prot(unsigned long vm_flags) >> -{ >> -#ifdef CONFIG_PPC_MEM_KEYS >> - return (vm_flags & VM_SAO) ? >> - __pgprot(_PAGE_SAO | vmflag_to_pte_pkey_bits(vm_flags)) : >> - __pgprot(0 | vmflag_to_pte_pkey_bits(vm_flags)); >> -#else >> - return (vm_flags & VM_SAO) ? __pgprot(_PAGE_SAO) : __pgprot(0); >> -#endif >> -} >> -#define arch_vm_get_page_prot(vm_flags) arch_vm_get_page_prot(vm_flags) >> - >> static inline bool arch_validate_prot(unsigned long prot, unsigned long addr) >> { >> if (prot & ~(PROT_READ | PROT_WRITE | PROT_EXEC | PROT_SEM | PROT_SAO)) >> diff --git a/arch/powerpc/mm/book3s64/pgtable.c b/arch/powerpc/mm/book3s64/pgtable.c >> index 052e6590f84f..d0319524e27f 100644 >> --- a/arch/powerpc/mm/book3s64/pgtable.c >> +++ b/arch/powerpc/mm/book3s64/pgtable.c >> @@ -7,6 +7,7 @@ >> #include >> #include >> #include >> +#include >> #include >> #include >> >> @@ -549,3 +550,22 @@ unsigned long memremap_compat_align(void) >> } >> EXPORT_SYMBOL_GPL(memremap_compat_align); >> #endif >> + >> +static pgprot_t __vm_get_page_prot(unsigned long vm_flags) >> +{ >> +#ifdef CONFIG_PPC_MEM_KEYS >> + return (vm_flags & VM_SAO) ? >> + __pgprot(_PAGE_SAO | vmflag_to_pte_pkey_bits(vm_flags)) : >> + __pgprot(0 | vmflag_to_pte_pkey_bits(vm_flags)); >> +#else >> + return (vm_flags & VM_SAO) ? __pgprot(_PAGE_SAO) : __pgprot(0); >> +#endif >> +} >> + >> +pgprot_t vm_get_page_prot(unsigned long vm_flags) >> +{ >> + return __pgprot(pgprot_val(protection_map[vm_flags & >> + (VM_READ|VM_WRITE|VM_EXEC|VM_SHARED)]) | >> + pgprot_val(__vm_get_page_prot(vm_flags))); >> +} >> +EXPORT_SYMBOL(vm_get_page_prot); > > This looks functionnaly OK, but I think we could go in the same > direction as ARM and try to integrate __vm_get_page_prot() inside > vm_get_page_prot() to get something simpler and cleaner: > > Something like below (untested): > > pgprot_t vm_get_page_prot(unsigned long vm_flags) > { > unsigned long prot = pgprot_val(protection_map[vm_flags & > (VM_READ|VM_WRITE|VM_EXEC|VM_SHARED)]); > > if (vm_flags & VM_SAO) > prot |= _PAGE_SAO > > #ifdef CONFIG_PPC_MEM_KEYS > prot |= vmflag_to_pte_pkey_bits(vm_flags); > #endif > > return __pgprot(prot); > } Okay, will integrate these functions into vm_get_page_prot() as suggested.