From patchwork Mon Jul 13 03:23:07 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Anshuman Khandual X-Patchwork-Id: 1327689 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (no SPF record) smtp.mailfrom=lists.infradead.org (client-ip=2001:8b0:10b:1231::1; helo=merlin.infradead.org; envelope-from=linux-snps-arc-bounces+incoming=patchwork.ozlabs.org@lists.infradead.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: ozlabs.org; dkim=pass (2048-bit key; secure) header.d=lists.infradead.org header.i=@lists.infradead.org header.a=rsa-sha256 header.s=merlin.20170209 header.b=tpLHNj7l; dkim-atps=neutral Received: from merlin.infradead.org (merlin.infradead.org [IPv6:2001:8b0:10b:1231::1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 4B4ptV2ttlz9sRk for ; Mon, 13 Jul 2020 13:25:06 +1000 (AEST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:MIME-Version:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:References:In-Reply-To:Message-Id:Date:Subject:To: From:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=QYIn1e1YfKcwZFPq6L9j+fXgXckNH616kypq4NiGohY=; b=tpLHNj7l1hufjXp5219XEZz4X1 tO4FqK6wiZW4j6HzT3PCFl9S1+cP8/T9wK56ii9BoAO00bIyXAvokJjBo343cQDtI9JDuKqgVmSZ2 q0jl5tFomn+ZavevT/47py82hCqZKq1Ws0O8az1iayfZtnqqDeoYLFMkaEYjUK83fvV7LowzfFgcc 6bgaw8an8PwknFTOvvvb53udtwiInwSPyvf+rFNjV+S92s2b4UeRgLS9PNUVg9cCxnZ3vOBn8sw+Y Wpxjx9mApjKZBSyMaw2PxwBT9tndB0DnlynTRuvBTKuQJzJKDzA6Iuh9nS+kv0BkHK7LCxQXnTw2/ RMXNWlYw==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1jup5R-0002PH-Fd; Mon, 13 Jul 2020 03:25:01 +0000 Received: from foss.arm.com ([217.140.110.172]) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1jup57-0002Fo-Ey; Mon, 13 Jul 2020 03:24:48 +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 9D1071FB; Sun, 12 Jul 2020 20:24:40 -0700 (PDT) Received: from p8cg001049571a15.arm.com (unknown [10.163.87.124]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 526E93F7D8; Sun, 12 Jul 2020 20:24:28 -0700 (PDT) From: Anshuman Khandual To: linux-mm@kvack.org Subject: [PATCH V5 4/4] Documentation/mm: Add descriptions for arch page table helpers Date: Mon, 13 Jul 2020 08:53:07 +0530 Message-Id: <1594610587-4172-5-git-send-email-anshuman.khandual@arm.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1594610587-4172-1-git-send-email-anshuman.khandual@arm.com> References: <1594610587-4172-1-git-send-email-anshuman.khandual@arm.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200712_232441_769241_5717AE1E X-CRM114-Status: GOOD ( 17.89 ) X-Spam-Score: -2.3 (--) X-Spam-Report: SpamAssassin version 3.4.4 on merlin.infradead.org summary: Content analysis details: (-2.3 points) pts rule name description ---- ---------------------- -------------------------------------------------- -2.3 RCVD_IN_DNSWL_MED RBL: Sender listed at https://www.dnswl.org/, medium trust [217.140.110.172 listed in list.dnswl.org] 0.0 SPF_HELO_NONE SPF: HELO does not publish an SPF Record -0.0 SPF_PASS SPF: sender matches SPF record X-BeenThere: linux-snps-arc@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on Synopsys ARC Processors List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-doc@vger.kernel.org, Catalin Marinas , Heiko Carstens , Paul Mackerras , "H. Peter Anvin" , agordeev@linux.ibm.com, Will Deacon , linux-riscv@lists.infradead.org, linux-arch@vger.kernel.org, linux-s390@vger.kernel.org, Jonathan Corbet , Michael Ellerman , x86@kernel.org, christophe.leroy@csgroup.eu, Mike Rapoport , Christian Borntraeger , Ingo Molnar , linux-arm-kernel@lists.infradead.org, ziy@nvidia.com, Benjamin Herrenschmidt , linux-snps-arc@lists.infradead.org, Vasily Gorbik , Anshuman Khandual , cai@lca.pw, Paul Walmsley , "Kirill A . Shutemov" , Thomas Gleixner , gerald.schaefer@de.ibm.com, christophe.leroy@c-s.fr, Vineet Gupta , linux-kernel@vger.kernel.org, Palmer Dabbelt , aneesh.kumar@linux.ibm.com, Borislav Petkov , Andrew Morton , linuxppc-dev@lists.ozlabs.org, rppt@kernel.org MIME-Version: 1.0 Sender: "linux-snps-arc" Errors-To: linux-snps-arc-bounces+incoming=patchwork.ozlabs.org@lists.infradead.org This adds a specific description file for all arch page table helpers which is in sync with the semantics being tested via CONFIG_DEBUG_VM_PGTABLE. All future changes either to these descriptions here or the debug test should always remain in sync. Cc: Jonathan Corbet Cc: Andrew Morton Cc: Gerald Schaefer Cc: Christophe Leroy Cc: Mike Rapoport Cc: Vineet Gupta Cc: Catalin Marinas Cc: Will Deacon Cc: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: Michael Ellerman Cc: Heiko Carstens Cc: Vasily Gorbik Cc: Christian Borntraeger Cc: Thomas Gleixner Cc: Ingo Molnar Cc: Borislav Petkov Cc: "H. Peter Anvin" Cc: Kirill A. Shutemov Cc: Paul Walmsley Cc: Palmer Dabbelt Cc: linux-snps-arc@lists.infradead.org Cc: linux-arm-kernel@lists.infradead.org Cc: linuxppc-dev@lists.ozlabs.org Cc: linux-s390@vger.kernel.org Cc: linux-riscv@lists.infradead.org Cc: x86@kernel.org Cc: linux-arch@vger.kernel.org Cc: linux-mm@kvack.org Cc: linux-doc@vger.kernel.org Cc: linux-kernel@vger.kernel.org Acked-by: Mike Rapoport Suggested-by: Mike Rapoport Signed-off-by: Anshuman Khandual --- Documentation/vm/arch_pgtable_helpers.rst | 258 ++++++++++++++++++++++ mm/debug_vm_pgtable.c | 6 + 2 files changed, 264 insertions(+) create mode 100644 Documentation/vm/arch_pgtable_helpers.rst diff --git a/Documentation/vm/arch_pgtable_helpers.rst b/Documentation/vm/arch_pgtable_helpers.rst new file mode 100644 index 000000000000..f3591ee3aaa8 --- /dev/null +++ b/Documentation/vm/arch_pgtable_helpers.rst @@ -0,0 +1,258 @@ +.. SPDX-License-Identifier: GPL-2.0 + +.. _arch_page_table_helpers: + +=============================== +Architecture Page Table Helpers +=============================== + +Generic MM expects architectures (with MMU) to provide helpers to create, access +and modify page table entries at various level for different memory functions. +These page table helpers need to conform to a common semantics across platforms. +Following tables describe the expected semantics which can also be tested during +boot via CONFIG_DEBUG_VM_PGTABLE option. All future changes in here or the debug +test need to be in sync. + +====================== +PTE Page Table Helpers +====================== + ++---------------------------+--------------------------------------------------+ +| pte_same | Tests whether both PTE entries are the same | ++---------------------------+--------------------------------------------------+ +| pte_bad | Tests a non-table mapped PTE | ++---------------------------+--------------------------------------------------+ +| pte_present | Tests a valid mapped PTE | ++---------------------------+--------------------------------------------------+ +| pte_young | Tests a young PTE | ++---------------------------+--------------------------------------------------+ +| pte_dirty | Tests a dirty PTE | ++---------------------------+--------------------------------------------------+ +| pte_write | Tests a writable PTE | ++---------------------------+--------------------------------------------------+ +| pte_special | Tests a special PTE | ++---------------------------+--------------------------------------------------+ +| pte_protnone | Tests a PROT_NONE PTE | ++---------------------------+--------------------------------------------------+ +| pte_devmap | Tests a ZONE_DEVICE mapped PTE | ++---------------------------+--------------------------------------------------+ +| pte_soft_dirty | Tests a soft dirty PTE | ++---------------------------+--------------------------------------------------+ +| pte_swp_soft_dirty | Tests a soft dirty swapped PTE | ++---------------------------+--------------------------------------------------+ +| pte_mkyoung | Creates a young PTE | ++---------------------------+--------------------------------------------------+ +| pte_mkold | Creates an old PTE | ++---------------------------+--------------------------------------------------+ +| pte_mkdirty | Creates a dirty PTE | ++---------------------------+--------------------------------------------------+ +| pte_mkclean | Creates a clean PTE | ++---------------------------+--------------------------------------------------+ +| pte_mkwrite | Creates a writable PTE | ++---------------------------+--------------------------------------------------+ +| pte_mkwrprotect | Creates a write protected PTE | ++---------------------------+--------------------------------------------------+ +| pte_mkspecial | Creates a special PTE | ++---------------------------+--------------------------------------------------+ +| pte_mkdevmap | Creates a ZONE_DEVICE mapped PTE | ++---------------------------+--------------------------------------------------+ +| pte_mksoft_dirty | Creates a soft dirty PTE | ++---------------------------+--------------------------------------------------+ +| pte_clear_soft_dirty | Clears a soft dirty PTE | ++---------------------------+--------------------------------------------------+ +| pte_swp_mksoft_dirty | Creates a soft dirty swapped PTE | ++---------------------------+--------------------------------------------------+ +| pte_swp_clear_soft_dirty | Clears a soft dirty swapped PTE | ++---------------------------+--------------------------------------------------+ +| pte_mknotpresent | Invalidates a mapped PTE | ++---------------------------+--------------------------------------------------+ +| ptep_get_and_clear | Clears a PTE | ++---------------------------+--------------------------------------------------+ +| ptep_get_and_clear_full | Clears a PTE | ++---------------------------+--------------------------------------------------+ +| ptep_test_and_clear_young | Clears young from a PTE | ++---------------------------+--------------------------------------------------+ +| ptep_set_wrprotect | Converts into a write protected PTE | ++---------------------------+--------------------------------------------------+ +| ptep_set_access_flags | Converts into a more permissive PTE | ++---------------------------+--------------------------------------------------+ + +====================== +PMD Page Table Helpers +====================== + ++---------------------------+--------------------------------------------------+ +| pmd_same | Tests whether both PMD entries are the same | ++---------------------------+--------------------------------------------------+ +| pmd_bad | Tests a non-table mapped PMD | ++---------------------------+--------------------------------------------------+ +| pmd_leaf | Tests a leaf mapped PMD | ++---------------------------+--------------------------------------------------+ +| pmd_huge | Tests a HugeTLB mapped PMD | ++---------------------------+--------------------------------------------------+ +| pmd_trans_huge | Tests a Transparent Huge Page (THP) at PMD | ++---------------------------+--------------------------------------------------+ +| pmd_present | Tests a valid mapped PMD | ++---------------------------+--------------------------------------------------+ +| pmd_young | Tests a young PMD | ++---------------------------+--------------------------------------------------+ +| pmd_dirty | Tests a dirty PMD | ++---------------------------+--------------------------------------------------+ +| pmd_write | Tests a writable PMD | ++---------------------------+--------------------------------------------------+ +| pmd_special | Tests a special PMD | ++---------------------------+--------------------------------------------------+ +| pmd_protnone | Tests a PROT_NONE PMD | ++---------------------------+--------------------------------------------------+ +| pmd_devmap | Tests a ZONE_DEVICE mapped PMD | ++---------------------------+--------------------------------------------------+ +| pmd_soft_dirty | Tests a soft dirty PMD | ++---------------------------+--------------------------------------------------+ +| pmd_swp_soft_dirty | Tests a soft dirty swapped PMD | ++---------------------------+--------------------------------------------------+ +| pmd_mkyoung | Creates a young PMD | ++---------------------------+--------------------------------------------------+ +| pmd_mkold | Creates an old PMD | ++---------------------------+--------------------------------------------------+ +| pmd_mkdirty | Creates a dirty PMD | ++---------------------------+--------------------------------------------------+ +| pmd_mkclean | Creates a clean PMD | ++---------------------------+--------------------------------------------------+ +| pmd_mkwrite | Creates a writable PMD | ++---------------------------+--------------------------------------------------+ +| pmd_mkwrprotect | Creates a write protected PMD | ++---------------------------+--------------------------------------------------+ +| pmd_mkspecial | Creates a special PMD | ++---------------------------+--------------------------------------------------+ +| pmd_mkdevmap | Creates a ZONE_DEVICE mapped PMD | ++---------------------------+--------------------------------------------------+ +| pmd_mksoft_dirty | Creates a soft dirty PMD | ++---------------------------+--------------------------------------------------+ +| pmd_clear_soft_dirty | Clears a soft dirty PMD | ++---------------------------+--------------------------------------------------+ +| pmd_swp_mksoft_dirty | Creates a soft dirty swapped PMD | ++---------------------------+--------------------------------------------------+ +| pmd_swp_clear_soft_dirty | Clears a soft dirty swapped PMD | ++---------------------------+--------------------------------------------------+ +| pmd_mkinvalid | Invalidates a mapped PMD [1] | ++---------------------------+--------------------------------------------------+ +| pmd_set_huge | Creates a PMD huge mapping | ++---------------------------+--------------------------------------------------+ +| pmd_clear_huge | Clears a PMD huge mapping | ++---------------------------+--------------------------------------------------+ +| pmdp_get_and_clear | Clears a PMD | ++---------------------------+--------------------------------------------------+ +| pmdp_get_and_clear_full | Clears a PMD | ++---------------------------+--------------------------------------------------+ +| pmdp_test_and_clear_young | Clears young from a PMD | ++---------------------------+--------------------------------------------------+ +| pmdp_set_wrprotect | Converts into a write protected PMD | ++---------------------------+--------------------------------------------------+ +| pmdp_set_access_flags | Converts into a more permissive PMD | ++---------------------------+--------------------------------------------------+ + +====================== +PUD Page Table Helpers +====================== + ++---------------------------+--------------------------------------------------+ +| pud_same | Tests whether both PUD entries are the same | ++---------------------------+--------------------------------------------------+ +| pud_bad | Tests a non-table mapped PUD | ++---------------------------+--------------------------------------------------+ +| pud_leaf | Tests a leaf mapped PUD | ++---------------------------+--------------------------------------------------+ +| pud_huge | Tests a HugeTLB mapped PUD | ++---------------------------+--------------------------------------------------+ +| pud_trans_huge | Tests a Transparent Huge Page (THP) at PUD | ++---------------------------+--------------------------------------------------+ +| pud_present | Tests a valid mapped PUD | ++---------------------------+--------------------------------------------------+ +| pud_young | Tests a young PUD | ++---------------------------+--------------------------------------------------+ +| pud_dirty | Tests a dirty PUD | ++---------------------------+--------------------------------------------------+ +| pud_write | Tests a writable PUD | ++---------------------------+--------------------------------------------------+ +| pud_devmap | Tests a ZONE_DEVICE mapped PUD | ++---------------------------+--------------------------------------------------+ +| pud_mkyoung | Creates a young PUD | ++---------------------------+--------------------------------------------------+ +| pud_mkold | Creates an old PUD | ++---------------------------+--------------------------------------------------+ +| pud_mkdirty | Creates a dirty PUD | ++---------------------------+--------------------------------------------------+ +| pud_mkclean | Creates a clean PUD | ++---------------------------+--------------------------------------------------+ +| pud_mkwrite | Creates a writable PUD | ++---------------------------+--------------------------------------------------+ +| pud_mkwrprotect | Creates a write protected PUD | ++---------------------------+--------------------------------------------------+ +| pud_mkdevmap | Creates a ZONE_DEVICE mapped PUD | ++---------------------------+--------------------------------------------------+ +| pud_mkinvalid | Invalidates a mapped PUD [1] | ++---------------------------+--------------------------------------------------+ +| pud_set_huge | Creates a PUD huge mapping | ++---------------------------+--------------------------------------------------+ +| pud_clear_huge | Clears a PUD huge mapping | ++---------------------------+--------------------------------------------------+ +| pudp_get_and_clear | Clears a PUD | ++---------------------------+--------------------------------------------------+ +| pudp_get_and_clear_full | Clears a PUD | ++---------------------------+--------------------------------------------------+ +| pudp_test_and_clear_young | Clears young from a PUD | ++---------------------------+--------------------------------------------------+ +| pudp_set_wrprotect | Converts into a write protected PUD | ++---------------------------+--------------------------------------------------+ +| pudp_set_access_flags | Converts into a more permissive PUD | ++---------------------------+--------------------------------------------------+ + +========================== +HugeTLB Page Table Helpers +========================== + ++---------------------------+--------------------------------------------------+ +| pte_huge | Tests a HugeTLB | ++---------------------------+--------------------------------------------------+ +| pte_mkhuge | Creates a HugeTLB | ++---------------------------+--------------------------------------------------+ +| huge_pte_dirty | Tests a dirty HugeTLB | ++---------------------------+--------------------------------------------------+ +| huge_pte_write | Tests a writable HugeTLB | ++---------------------------+--------------------------------------------------+ +| huge_pte_mkdirty | Creates a dirty HugeTLB | ++---------------------------+--------------------------------------------------+ +| huge_pte_mkwrite | Creates a writable HugeTLB | ++---------------------------+--------------------------------------------------+ +| huge_pte_mkwrprotect | Creates a write protected HugeTLB | ++---------------------------+--------------------------------------------------+ +| huge_ptep_get_and_clear | Clears a HugeTLB | ++---------------------------+--------------------------------------------------+ +| huge_ptep_set_wrprotect | Converts into a write protected HugeTLB | ++---------------------------+--------------------------------------------------+ +| huge_ptep_set_access_flags | Converts into a more permissive HugeTLB | ++---------------------------+--------------------------------------------------+ + +======================== +SWAP Page Table Helpers +======================== + ++---------------------------+--------------------------------------------------+ +| __pte_to_swp_entry | Creates a swapped entry (arch) from a mapped PTE | ++---------------------------+--------------------------------------------------+ +| __swp_to_pte_entry | Creates a mapped PTE from a swapped entry (arch) | ++---------------------------+--------------------------------------------------+ +| __pmd_to_swp_entry | Creates a swapped entry (arch) from a mapped PMD | ++---------------------------+--------------------------------------------------+ +| __swp_to_pmd_entry | Creates a mapped PMD from a swapped entry (arch) | ++---------------------------+--------------------------------------------------+ +| is_migration_entry | Tests a migration (read or write) swapped entry | ++---------------------------+--------------------------------------------------+ +| is_write_migration_entry | Tests a write migration swapped entry | ++---------------------------+--------------------------------------------------+ +| make_migration_entry_read | Converts into read migration swapped entry | ++---------------------------+--------------------------------------------------+ +| make_migration_entry | Creates a migration swapped entry (read or write)| ++---------------------------+--------------------------------------------------+ + +[1] https://lore.kernel.org/linux-mm/20181017020930.GN30832@redhat.com/ diff --git a/mm/debug_vm_pgtable.c b/mm/debug_vm_pgtable.c index 0db4390435be..e86c3d824693 100644 --- a/mm/debug_vm_pgtable.c +++ b/mm/debug_vm_pgtable.c @@ -31,6 +31,12 @@ #include #include +/* + * Please refer Documentation/vm/arch_pgtable_helpers.rst for the semantics + * expectations that are being validated here. All future changes in here + * or the documentation need to be in sync. + */ + #define VMFLAGS (VM_READ|VM_WRITE|VM_EXEC) /*