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 868A1C433EF for ; Fri, 4 Feb 2022 02:57:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1356175AbiBDC5q (ORCPT ); Thu, 3 Feb 2022 21:57:46 -0500 Received: from foss.arm.com ([217.140.110.172]:36374 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229967AbiBDC5p (ORCPT ); Thu, 3 Feb 2022 21:57:45 -0500 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 24FFF1435; Thu, 3 Feb 2022 18:57:45 -0800 (PST) Received: from [10.163.45.195] (unknown [10.163.45.195]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 981FE3F774; Thu, 3 Feb 2022 18:57:41 -0800 (PST) Subject: Re: [RFC V1 04/31] powerpc/mm: Enable ARCH_HAS_VM_GET_PAGE_PROT To: Mike Rapoport Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, hch@infradead.org, akpm@linux-foundation.org, Michael Ellerman , Paul Mackerras , linuxppc-dev@lists.ozlabs.org References: <1643029028-12710-1-git-send-email-anshuman.khandual@arm.com> <1643029028-12710-5-git-send-email-anshuman.khandual@arm.com> From: Anshuman Khandual Message-ID: <46e15116-78fb-e6fe-e0f0-fe776f9348c3@arm.com> Date: Fri, 4 Feb 2022 08:27:37 +0530 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2/3/22 11:45 PM, Mike Rapoport wrote: > On Mon, Jan 24, 2022 at 06:26:41PM +0530, Anshuman Khandual wrote: >> This defines and exports a platform specific custom vm_get_page_prot() via >> subscribing ARCH_HAS_VM_GET_PAGE_PROT. Subsequently all __SXXX and __PXXX >> macros can be dropped which are no longer needed. While here, this also >> localizes arch_vm_get_page_prot() as powerpc_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 | 3 +- >> arch/powerpc/include/asm/pgtable.h | 19 ------------ >> arch/powerpc/mm/mmap.c | 47 ++++++++++++++++++++++++++++++ >> 4 files changed, 49 insertions(+), 21 deletions(-) >> >> diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig >> index b779603978e1..ddb4a3687c05 100644 >> --- a/arch/powerpc/Kconfig >> +++ b/arch/powerpc/Kconfig >> @@ -135,6 +135,7 @@ 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 >> 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..7b10c2031e82 100644 >> --- a/arch/powerpc/include/asm/mman.h >> +++ b/arch/powerpc/include/asm/mman.h >> @@ -24,7 +24,7 @@ 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) >> +static inline pgprot_t powerpc_vm_get_page_prot(unsigned long vm_flags) >> { >> #ifdef CONFIG_PPC_MEM_KEYS >> return (vm_flags & VM_SAO) ? >> @@ -34,7 +34,6 @@ static inline pgprot_t arch_vm_get_page_prot(unsigned long vm_flags) >> 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) >> { >> diff --git a/arch/powerpc/include/asm/pgtable.h b/arch/powerpc/include/asm/pgtable.h >> index d564d0ecd4cd..3cbb6de20f9d 100644 >> --- a/arch/powerpc/include/asm/pgtable.h >> +++ b/arch/powerpc/include/asm/pgtable.h >> @@ -20,25 +20,6 @@ struct mm_struct; >> #include >> #endif /* !CONFIG_PPC_BOOK3S */ >> >> -/* Note due to the way vm flags are laid out, the bits are XWR */ >> -#define __P000 PAGE_NONE >> -#define __P001 PAGE_READONLY >> -#define __P010 PAGE_COPY >> -#define __P011 PAGE_COPY >> -#define __P100 PAGE_READONLY_X >> -#define __P101 PAGE_READONLY_X >> -#define __P110 PAGE_COPY_X >> -#define __P111 PAGE_COPY_X >> - >> -#define __S000 PAGE_NONE >> -#define __S001 PAGE_READONLY >> -#define __S010 PAGE_SHARED >> -#define __S011 PAGE_SHARED >> -#define __S100 PAGE_READONLY_X >> -#define __S101 PAGE_READONLY_X >> -#define __S110 PAGE_SHARED_X >> -#define __S111 PAGE_SHARED_X >> - >> #ifndef __ASSEMBLY__ >> >> #ifndef MAX_PTRS_PER_PGD >> diff --git a/arch/powerpc/mm/mmap.c b/arch/powerpc/mm/mmap.c >> index c475cf810aa8..7f05e7903bd2 100644 >> --- a/arch/powerpc/mm/mmap.c >> +++ b/arch/powerpc/mm/mmap.c >> @@ -254,3 +254,50 @@ void arch_pick_mmap_layout(struct mm_struct *mm, struct rlimit *rlim_stack) >> mm->get_unmapped_area = arch_get_unmapped_area_topdown; >> } >> } >> + >> +static inline pgprot_t __vm_get_page_prot(unsigned long vm_flags) >> +{ >> + switch (vm_flags & (VM_READ | VM_WRITE | VM_EXEC | VM_SHARED)) { >> + case VM_NONE: >> + return PAGE_NONE; >> + case VM_READ: >> + return PAGE_READONLY; >> + case VM_WRITE: >> + return PAGE_COPY; >> + case VM_READ | VM_WRITE: >> + return PAGE_COPY; >> + case VM_EXEC: >> + return PAGE_READONLY_X; >> + case VM_EXEC | VM_READ: >> + return PAGE_READONLY_X; >> + case VM_EXEC | VM_WRITE: >> + return PAGE_COPY_X; >> + case VM_EXEC | VM_READ | VM_WRITE: >> + return PAGE_COPY_X; >> + case VM_SHARED: >> + return PAGE_NONE; >> + case VM_SHARED | VM_READ: >> + return PAGE_READONLY; >> + case VM_SHARED | VM_WRITE: >> + return PAGE_SHARED; >> + case VM_SHARED | VM_READ | VM_WRITE: >> + return PAGE_SHARED; >> + case VM_SHARED | VM_EXEC: >> + return PAGE_READONLY_X; >> + case VM_SHARED | VM_EXEC | VM_READ: >> + return PAGE_READONLY_X; >> + case VM_SHARED | VM_EXEC | VM_WRITE: >> + return PAGE_SHARED_X; >> + case VM_SHARED | VM_EXEC | VM_READ | VM_WRITE: >> + return PAGE_SHARED_X; >> + default: >> + BUILD_BUG(); >> + } >> +} >> + >> +pgprot_t vm_get_page_prot(unsigned long vm_flags) >> +{ >> + return __pgprot(pgprot_val(__vm_get_page_prot(vm_flags)) | >> + pgprot_val(powerpc_vm_get_page_prot(vm_flags))); > Any reason to keep powerpc_vm_get_page_prot() rather than open code it > here? > > This applies to other architectures that implement arch_vm_get_page_prot() > and/or arch_filter_pgprot() as well. Just to minimize the code churn ! But I will be happy to open code them here (and in other platforms) if that will be preferred.