From patchwork Mon Jun 15 03:37:57 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Anshuman Khandual X-Patchwork-Id: 1309146 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 49lcjr3NzNz9sQx for ; Mon, 15 Jun 2020 13:48:00 +1000 (AEST) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=arm.com Received: from bilbo.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 49lcjr1rKszDqNm for ; Mon, 15 Jun 2020 13:48:00 +1000 (AEST) X-Original-To: linuxppc-dev@lists.ozlabs.org Delivered-To: linuxppc-dev@lists.ozlabs.org Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=arm.com (client-ip=217.140.110.172; helo=foss.arm.com; envelope-from=anshuman.khandual@arm.com; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=arm.com Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lists.ozlabs.org (Postfix) with ESMTP id 49lcWW5SSPzDqLZ for ; Mon, 15 Jun 2020 13:39:03 +1000 (AEST) 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 4CCBA11B3; Sun, 14 Jun 2020 20:39:02 -0700 (PDT) Received: from p8cg001049571a15.arm.com (unknown [10.163.79.186]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 9AE783F71F; Sun, 14 Jun 2020 20:38:52 -0700 (PDT) From: Anshuman Khandual To: linux-mm@kvack.org Subject: [PATCH V3 4/4] Documentation/mm: Add descriptions for arch page table helpers Date: Mon, 15 Jun 2020 09:07:57 +0530 Message-Id: <1592192277-8421-5-git-send-email-anshuman.khandual@arm.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1592192277-8421-1-git-send-email-anshuman.khandual@arm.com> References: <1592192277-8421-1-git-send-email-anshuman.khandual@arm.com> X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-doc@vger.kernel.org, Heiko Carstens , Paul Mackerras , "H. Peter Anvin" , linux-riscv@lists.infradead.org, Will Deacon , linux-arch@vger.kernel.org, linux-s390@vger.kernel.org, Jonathan Corbet , x86@kernel.org, Mike Rapoport , Christian Borntraeger , Ingo Molnar , linux-arm-kernel@lists.infradead.org, ziy@nvidia.com, Catalin Marinas , linux-snps-arc@lists.infradead.org, Vasily Gorbik , Anshuman Khandual , Borislav Petkov , 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 , Andrew Morton , linuxppc-dev@lists.ozlabs.org Errors-To: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org Sender: "Linuxppc-dev" 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: 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 Suggested-by: Mike Rapoport Signed-off-by: Anshuman Khandual Acked-by: Mike Rapoport --- 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..cd7609b05446 --- /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 PMD | +-------------------------------------------------------------------------------- +| pud_mkwrprotect | Creates a write protected PMD | +-------------------------------------------------------------------------------- +| pud_mkdevmap | Creates a ZONE_DEVICE mapped PMD | +-------------------------------------------------------------------------------- +| 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 mapepd 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 mapepd 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 536f3b1b3ad6..a2936938ed78 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) /*