From patchwork Mon Feb 14 02:30:24 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Anshuman Khandual X-Patchwork-Id: 12744793 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 9D3F2C433F5 for ; Mon, 14 Feb 2022 02:31:07 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 2F4B16B0078; Sun, 13 Feb 2022 21:31:07 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 27CD66B007B; Sun, 13 Feb 2022 21:31:07 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 16C466B007D; Sun, 13 Feb 2022 21:31:07 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0079.hostedemail.com [216.40.44.79]) by kanga.kvack.org (Postfix) with ESMTP id 066536B0078 for ; Sun, 13 Feb 2022 21:31:07 -0500 (EST) Received: from smtpin13.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id B33FA8249980 for ; Mon, 14 Feb 2022 02:31:06 +0000 (UTC) X-FDA: 79139808132.13.4EA0C63 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by imf06.hostedemail.com (Postfix) with ESMTP id 32044180004 for ; Mon, 14 Feb 2022 02:31:06 +0000 (UTC) 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 79722106F; Sun, 13 Feb 2022 18:31:05 -0800 (PST) Received: from p8cg001049571a15.arm.com (unknown [10.163.47.15]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 063913F718; Sun, 13 Feb 2022 18:31:02 -0800 (PST) From: Anshuman Khandual To: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org, Anshuman Khandual , Christoph Hellwig , Andrew Morton , linux-arch@vger.kernel.org Subject: [PATCH 01/30] mm/debug_vm_pgtable: Drop protection_map[] usage Date: Mon, 14 Feb 2022 08:00:24 +0530 Message-Id: <1644805853-21338-2-git-send-email-anshuman.khandual@arm.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1644805853-21338-1-git-send-email-anshuman.khandual@arm.com> References: <1644805853-21338-1-git-send-email-anshuman.khandual@arm.com> X-Rspam-User: X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 32044180004 X-Stat-Signature: 9krf53czjpqabginkwdj4w9gj6u1efcy Authentication-Results: imf06.hostedemail.com; dkim=none; dmarc=pass (policy=none) header.from=arm.com; spf=pass (imf06.hostedemail.com: domain of anshuman.khandual@arm.com designates 217.140.110.172 as permitted sender) smtp.mailfrom=anshuman.khandual@arm.com X-HE-Tag: 1644805866-635722 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: Although protection_map[] contains the platform defined page protection map for a given vm_flags combination, vm_get_page_prot() is the right interface to use. This will also reduce dependency on protection_map[] which is going to be dropped off completely later on. Cc: Andrew Morton Cc: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Anshuman Khandual --- mm/debug_vm_pgtable.c | 31 +++++++++++++++++++------------ 1 file changed, 19 insertions(+), 12 deletions(-) diff --git a/mm/debug_vm_pgtable.c b/mm/debug_vm_pgtable.c index db2abd9e415b..30fd11a2ed32 100644 --- a/mm/debug_vm_pgtable.c +++ b/mm/debug_vm_pgtable.c @@ -93,7 +93,7 @@ struct pgtable_debug_args { static void __init pte_basic_tests(struct pgtable_debug_args *args, int idx) { - pgprot_t prot = protection_map[idx]; + pgprot_t prot = vm_get_page_prot(idx); pte_t pte = pfn_pte(args->fixed_pte_pfn, prot); unsigned long val = idx, *ptr = &val; @@ -101,7 +101,7 @@ static void __init pte_basic_tests(struct pgtable_debug_args *args, int idx) /* * This test needs to be executed after the given page table entry - * is created with pfn_pte() to make sure that protection_map[idx] + * is created with pfn_pte() to make sure that vm_get_page_prot(idx) * does not have the dirty bit enabled from the beginning. This is * important for platforms like arm64 where (!PTE_RDONLY) indicate * dirty bit being set. @@ -190,7 +190,7 @@ static void __init pte_savedwrite_tests(struct pgtable_debug_args *args) #ifdef CONFIG_TRANSPARENT_HUGEPAGE static void __init pmd_basic_tests(struct pgtable_debug_args *args, int idx) { - pgprot_t prot = protection_map[idx]; + pgprot_t prot = vm_get_page_prot(idx); unsigned long val = idx, *ptr = &val; pmd_t pmd; @@ -202,7 +202,7 @@ static void __init pmd_basic_tests(struct pgtable_debug_args *args, int idx) /* * This test needs to be executed after the given page table entry - * is created with pfn_pmd() to make sure that protection_map[idx] + * is created with pfn_pmd() to make sure that vm_get_page_prot(idx) * does not have the dirty bit enabled from the beginning. This is * important for platforms like arm64 where (!PTE_RDONLY) indicate * dirty bit being set. @@ -325,7 +325,7 @@ static void __init pmd_savedwrite_tests(struct pgtable_debug_args *args) #ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD static void __init pud_basic_tests(struct pgtable_debug_args *args, int idx) { - pgprot_t prot = protection_map[idx]; + pgprot_t prot = vm_get_page_prot(idx); unsigned long val = idx, *ptr = &val; pud_t pud; @@ -337,7 +337,7 @@ static void __init pud_basic_tests(struct pgtable_debug_args *args, int idx) /* * This test needs to be executed after the given page table entry - * is created with pfn_pud() to make sure that protection_map[idx] + * is created with pfn_pud() to make sure that vm_get_page_prot(idx) * does not have the dirty bit enabled from the beginning. This is * important for platforms like arm64 where (!PTE_RDONLY) indicate * dirty bit being set. @@ -1106,14 +1106,14 @@ static int __init init_args(struct pgtable_debug_args *args) /* * Initialize the debugging data. * - * protection_map[0] (or even protection_map[8]) will help create - * page table entries with PROT_NONE permission as required for - * pxx_protnone_tests(). + * vm_get_page_prot(VM_NONE) or vm_get_page_prot(VM_SHARED|VM_NONE) + * will help create page table entries with PROT_NONE permission as + * required for pxx_protnone_tests(). */ memset(args, 0, sizeof(*args)); args->vaddr = get_random_vaddr(); args->page_prot = vm_get_page_prot(VMFLAGS); - args->page_prot_none = protection_map[0]; + args->page_prot_none = vm_get_page_prot(VM_NONE); args->is_contiguous_page = false; args->pud_pfn = ULONG_MAX; args->pmd_pfn = ULONG_MAX; @@ -1248,12 +1248,19 @@ static int __init debug_vm_pgtable(void) return ret; /* - * Iterate over the protection_map[] to make sure that all + * Iterate over each possible vm_flags to make sure that all * the basic page table transformation validations just hold * true irrespective of the starting protection value for a * given page table entry. + * + * Protection based vm_flags combinatins are always linear + * and increasing i.e starting from VM_NONE and going upto + * (VM_SHARED | READ | WRITE | EXEC). */ - for (idx = 0; idx < ARRAY_SIZE(protection_map); idx++) { +#define VM_FLAGS_START (VM_NONE) +#define VM_FLAGS_END (VM_SHARED | VM_EXEC | VM_WRITE | VM_READ) + + for (idx = VM_FLAGS_START; idx <= VM_FLAGS_END; idx++) { pte_basic_tests(&args, idx); pmd_basic_tests(&args, idx); pud_basic_tests(&args, idx);