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linux/arch/arm/include/asm/pgtable-3level.h

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treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 333 Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not write to the free software foundation inc 59 temple place suite 330 boston ma 02111 1307 usa extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 136 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexios Zavras <alexios.zavras@intel.com> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190530000436.384967451@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-29 16:57:47 -07:00
/* SPDX-License-Identifier: GPL-2.0-only */
ARM: LPAE: Introduce the 3-level page table format definitions This patch introduces the pgtable-3level*.h files with definitions specific to the LPAE page table format (3 levels of page tables). Each table is 4KB and has 512 64-bit entries. An entry can point to a 40-bit physical address. The young, write and exec software bits share the corresponding hardware bits (negated). Other software bits use spare bits in the PTE. The patch also changes some variable types from unsigned long or int to pteval_t or pgprot_t. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2011-11-22 17:30:29 +00:00
/*
* arch/arm/include/asm/pgtable-3level.h
*
* Copyright (C) 2011 ARM Ltd.
* Author: Catalin Marinas <catalin.marinas@arm.com>
*/
#ifndef _ASM_PGTABLE_3LEVEL_H
#define _ASM_PGTABLE_3LEVEL_H
/*
* With LPAE, there are 3 levels of page tables. Each level has 512 entries of
* 8 bytes each, occupying a 4K page. The first level table covers a range of
* 512GB, each entry representing 1GB. Since we are limited to 4GB input
* address range, only 4 entries in the PGD are used.
*
* There are enough spare bits in a page table entry for the kernel specific
* state.
*/
#define PTRS_PER_PTE 512
#define PTRS_PER_PMD 512
#define PTRS_PER_PGD 4
ARM: lpae: fix definition of PTE_HWTABLE_PTRS For 2-level page tables, PTE_HWTABLE_PTRS describes the offset between Linux PTEs and hardware PTEs. On LPAE, there is no distinction (since we have 64-bit descriptors with plenty of space) so PTE_HWTABLE_PTRS should be 0. Unfortunately, it is wrongly defined as PTRS_PER_PTE, meaning that current pte table flushing is off by a page. Luckily, all current LPAE implementations are SMP, so the hardware walker can snoop L1. This patch fixes the broken definition. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2013-05-02 13:52:01 +01:00
#define PTE_HWTABLE_PTRS (0)
ARM: LPAE: Introduce the 3-level page table format definitions This patch introduces the pgtable-3level*.h files with definitions specific to the LPAE page table format (3 levels of page tables). Each table is 4KB and has 512 64-bit entries. An entry can point to a 40-bit physical address. The young, write and exec software bits share the corresponding hardware bits (negated). Other software bits use spare bits in the PTE. The patch also changes some variable types from unsigned long or int to pteval_t or pgprot_t. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2011-11-22 17:30:29 +00:00
#define PTE_HWTABLE_OFF (0)
#define PTE_HWTABLE_SIZE (PTRS_PER_PTE * sizeof(u64))
arch: pgtable: define MAX_POSSIBLE_PHYSMEM_BITS where needed Stefan Agner reported a bug when using zsram on 32-bit Arm machines with RAM above the 4GB address boundary: Unable to handle kernel NULL pointer dereference at virtual address 00000000 pgd = a27bd01c [00000000] *pgd=236a0003, *pmd=1ffa64003 Internal error: Oops: 207 [#1] SMP ARM Modules linked in: mdio_bcm_unimac(+) brcmfmac cfg80211 brcmutil raspberrypi_hwmon hci_uart crc32_arm_ce bcm2711_thermal phy_generic genet CPU: 0 PID: 123 Comm: mkfs.ext4 Not tainted 5.9.6 #1 Hardware name: BCM2711 PC is at zs_map_object+0x94/0x338 LR is at zram_bvec_rw.constprop.0+0x330/0xa64 pc : [<c0602b38>] lr : [<c0bda6a0>] psr: 60000013 sp : e376bbe0 ip : 00000000 fp : c1e2921c r10: 00000002 r9 : c1dda730 r8 : 00000000 r7 : e8ff7a00 r6 : 00000000 r5 : 02f9ffa0 r4 : e3710000 r3 : 000fdffe r2 : c1e0ce80 r1 : ebf979a0 r0 : 00000000 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5383d Table: 235c2a80 DAC: fffffffd Process mkfs.ext4 (pid: 123, stack limit = 0x495a22e6) Stack: (0xe376bbe0 to 0xe376c000) As it turns out, zsram needs to know the maximum memory size, which is defined in MAX_PHYSMEM_BITS when CONFIG_SPARSEMEM is set, or in MAX_POSSIBLE_PHYSMEM_BITS on the x86 architecture. The same problem will be hit on all 32-bit architectures that have a physical address space larger than 4GB and happen to not enable sparsemem and include asm/sparsemem.h from asm/pgtable.h. After the initial discussion, I suggested just always defining MAX_POSSIBLE_PHYSMEM_BITS whenever CONFIG_PHYS_ADDR_T_64BIT is set, or provoking a build error otherwise. This addresses all configurations that can currently have this runtime bug, but leaves all other configurations unchanged. I looked up the possible number of bits in source code and datasheets, here is what I found: - on ARC, CONFIG_ARC_HAS_PAE40 controls whether 32 or 40 bits are used - on ARM, CONFIG_LPAE enables 40 bit addressing, without it we never support more than 32 bits, even though supersections in theory allow up to 40 bits as well. - on MIPS, some MIPS32r1 or later chips support 36 bits, and MIPS32r5 XPA supports up to 60 bits in theory, but 40 bits are more than anyone will ever ship - On PowerPC, there are three different implementations of 36 bit addressing, but 32-bit is used without CONFIG_PTE_64BIT - On RISC-V, the normal page table format can support 34 bit addressing. There is no highmem support on RISC-V, so anything above 2GB is unused, but it might be useful to eventually support CONFIG_ZRAM for high pages. Fixes: 61989a80fb3a ("staging: zsmalloc: zsmalloc memory allocation library") Fixes: 02390b87a945 ("mm/zsmalloc: Prepare to variable MAX_PHYSMEM_BITS") Acked-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Reviewed-by: Stefan Agner <stefan@agner.ch> Tested-by: Stefan Agner <stefan@agner.ch> Acked-by: Mike Rapoport <rppt@linux.ibm.com> Link: https://lore.kernel.org/linux-mm/bdfa44bf1c570b05d6c70898e2bbb0acf234ecdf.1604762181.git.stefan@agner.ch/ Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2020-11-11 17:52:58 +01:00
#define MAX_POSSIBLE_PHYSMEM_BITS 40
ARM: LPAE: Introduce the 3-level page table format definitions This patch introduces the pgtable-3level*.h files with definitions specific to the LPAE page table format (3 levels of page tables). Each table is 4KB and has 512 64-bit entries. An entry can point to a 40-bit physical address. The young, write and exec software bits share the corresponding hardware bits (negated). Other software bits use spare bits in the PTE. The patch also changes some variable types from unsigned long or int to pteval_t or pgprot_t. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2011-11-22 17:30:29 +00:00
/*
* PGDIR_SHIFT determines the size a top-level page table entry can map.
*/
#define PGDIR_SHIFT 30
/*
* PMD_SHIFT determines the size a middle-level page table entry can map.
*/
#define PMD_SHIFT 21
#define PMD_SIZE (1UL << PMD_SHIFT)
ARM: LPAE: use signed arithmetic for mask definitions This patch applies to PAGE_MASK, PMD_MASK, and PGDIR_MASK, where forcing unsigned long math truncates the mask at the 32-bits. This clearly does bad things on PAE systems. This patch fixes this problem by defining these masks as signed quantities. We then rely on sign extension to do the right thing. Signed-off-by: Cyril Chemparathy <cyril@ti.com> Signed-off-by: Vitaly Andrianov <vitalya@ti.com> Reviewed-by: Nicolas Pitre <nico@linaro.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Tested-by: Subash Patel <subash.rp@samsung.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2012-07-22 13:40:38 -04:00
#define PMD_MASK (~((1 << PMD_SHIFT) - 1))
ARM: LPAE: Introduce the 3-level page table format definitions This patch introduces the pgtable-3level*.h files with definitions specific to the LPAE page table format (3 levels of page tables). Each table is 4KB and has 512 64-bit entries. An entry can point to a 40-bit physical address. The young, write and exec software bits share the corresponding hardware bits (negated). Other software bits use spare bits in the PTE. The patch also changes some variable types from unsigned long or int to pteval_t or pgprot_t. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2011-11-22 17:30:29 +00:00
#define PGDIR_SIZE (1UL << PGDIR_SHIFT)
ARM: LPAE: use signed arithmetic for mask definitions This patch applies to PAGE_MASK, PMD_MASK, and PGDIR_MASK, where forcing unsigned long math truncates the mask at the 32-bits. This clearly does bad things on PAE systems. This patch fixes this problem by defining these masks as signed quantities. We then rely on sign extension to do the right thing. Signed-off-by: Cyril Chemparathy <cyril@ti.com> Signed-off-by: Vitaly Andrianov <vitalya@ti.com> Reviewed-by: Nicolas Pitre <nico@linaro.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Tested-by: Subash Patel <subash.rp@samsung.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2012-07-22 13:40:38 -04:00
#define PGDIR_MASK (~((1 << PGDIR_SHIFT) - 1))
ARM: LPAE: Introduce the 3-level page table format definitions This patch introduces the pgtable-3level*.h files with definitions specific to the LPAE page table format (3 levels of page tables). Each table is 4KB and has 512 64-bit entries. An entry can point to a 40-bit physical address. The young, write and exec software bits share the corresponding hardware bits (negated). Other software bits use spare bits in the PTE. The patch also changes some variable types from unsigned long or int to pteval_t or pgprot_t. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2011-11-22 17:30:29 +00:00
/*
* section address mask and size definitions.
*/
#define SECTION_SHIFT 21
#define SECTION_SIZE (1UL << SECTION_SHIFT)
ARM: LPAE: use signed arithmetic for mask definitions This patch applies to PAGE_MASK, PMD_MASK, and PGDIR_MASK, where forcing unsigned long math truncates the mask at the 32-bits. This clearly does bad things on PAE systems. This patch fixes this problem by defining these masks as signed quantities. We then rely on sign extension to do the right thing. Signed-off-by: Cyril Chemparathy <cyril@ti.com> Signed-off-by: Vitaly Andrianov <vitalya@ti.com> Reviewed-by: Nicolas Pitre <nico@linaro.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Tested-by: Subash Patel <subash.rp@samsung.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2012-07-22 13:40:38 -04:00
#define SECTION_MASK (~((1 << SECTION_SHIFT) - 1))
ARM: LPAE: Introduce the 3-level page table format definitions This patch introduces the pgtable-3level*.h files with definitions specific to the LPAE page table format (3 levels of page tables). Each table is 4KB and has 512 64-bit entries. An entry can point to a 40-bit physical address. The young, write and exec software bits share the corresponding hardware bits (negated). Other software bits use spare bits in the PTE. The patch also changes some variable types from unsigned long or int to pteval_t or pgprot_t. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2011-11-22 17:30:29 +00:00
#define USER_PTRS_PER_PGD (PAGE_OFFSET / PGDIR_SIZE)
ARM: mm: HugeTLB support for LPAE systems. This patch adds support for hugetlbfs based on the x86 implementation. It allows mapping of 2MB sections (see Documentation/vm/hugetlbpage.txt for usage). The 64K pages configuration is not supported (section size is 512MB in this case). Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> [steve.capper@linaro.org: symbolic constants replace numbers in places. Split up into multiple files, to simplify future non-LPAE support, removed huge_pmd_share code, as this is very rarely executed, Added PROT_NONE support]. Signed-off-by: Steve Capper <steve.capper@linaro.org> Reviewed-by: Will Deacon <will.deacon@arm.com>
2012-07-25 14:32:38 +01:00
/*
* Hugetlb definitions.
*/
#define HPAGE_SHIFT PMD_SHIFT
#define HPAGE_SIZE (_AC(1, UL) << HPAGE_SHIFT)
#define HPAGE_MASK (~(HPAGE_SIZE - 1))
#define HUGETLB_PAGE_ORDER (HPAGE_SHIFT - PAGE_SHIFT)
ARM: LPAE: Introduce the 3-level page table format definitions This patch introduces the pgtable-3level*.h files with definitions specific to the LPAE page table format (3 levels of page tables). Each table is 4KB and has 512 64-bit entries. An entry can point to a 40-bit physical address. The young, write and exec software bits share the corresponding hardware bits (negated). Other software bits use spare bits in the PTE. The patch also changes some variable types from unsigned long or int to pteval_t or pgprot_t. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2011-11-22 17:30:29 +00:00
/*
* "Linux" PTE definitions for LPAE.
*
* These bits overlap with the hardware bits but the naming is preserved for
* consistency with the classic page table format.
*/
ARM: mm: introduce L_PTE_VALID for page table entries For long-descriptor translation table formats, the ARMv7 architecture defines the last two bits of the second- and third-level descriptors to be: x0b - Invalid 01b - Block (second-level), Reserved (third-level) 11b - Table (second-level), Page (third-level) This allows us to define L_PTE_PRESENT as (3 << 0) and use this value to create ptes directly. However, when determining whether a given pte value is present in the low-level page table accessors, we only need to check the least significant bit of the descriptor, allowing us to write faulting, present entries which are required for PROT_NONE mappings. This patch introduces L_PTE_VALID, which can be used to test whether a pte should fault, and updates the low-level page table accessors accordingly. Signed-off-by: Will Deacon <will.deacon@arm.com>
2012-07-19 11:51:05 +01:00
#define L_PTE_VALID (_AT(pteval_t, 1) << 0) /* Valid */
#define L_PTE_PRESENT (_AT(pteval_t, 3) << 0) /* Present */
ARM: LPAE: Introduce the 3-level page table format definitions This patch introduces the pgtable-3level*.h files with definitions specific to the LPAE page table format (3 levels of page tables). Each table is 4KB and has 512 64-bit entries. An entry can point to a 40-bit physical address. The young, write and exec software bits share the corresponding hardware bits (negated). Other software bits use spare bits in the PTE. The patch also changes some variable types from unsigned long or int to pteval_t or pgprot_t. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2011-11-22 17:30:29 +00:00
#define L_PTE_USER (_AT(pteval_t, 1) << 6) /* AP[1] */
#define L_PTE_SHARED (_AT(pteval_t, 3) << 8) /* SH[1:0], inner shareable */
#define L_PTE_YOUNG (_AT(pteval_t, 1) << 10) /* AF */
#define L_PTE_XN (_AT(pteval_t, 1) << 54) /* XN */
ARM: 8109/1: mm: Modify pte_write and pmd_write logic for LPAE For LPAE, we have the following means for encoding writable or dirty ptes: L_PTE_DIRTY L_PTE_RDONLY !pte_dirty && !pte_write 0 1 !pte_dirty && pte_write 0 1 pte_dirty && !pte_write 1 1 pte_dirty && pte_write 1 0 So we can't distinguish between writeable clean ptes and read only ptes. This can cause problems with ptes being incorrectly flagged as read only when they are writeable but not dirty. This patch renumbers L_PTE_RDONLY from AP[2] to a software bit #58, and adds additional logic to set AP[2] whenever the pte is read only or not dirty. That way we can distinguish between clean writeable ptes and read only ptes. HugeTLB pages will use this new logic automatically. We need to add some logic to Transparent HugePages to ensure that they correctly interpret the revised pgprot permissions (L_PTE_RDONLY has moved and no longer matches PMD_SECT_AP2). In the process of revising THP, the names of the PMD software bits have been prefixed with L_ to make them easier to distinguish from their hardware bit counterparts. Signed-off-by: Steve Capper <steve.capper@linaro.org> Reviewed-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-07-18 16:16:15 +01:00
#define L_PTE_DIRTY (_AT(pteval_t, 1) << 55)
#define L_PTE_SPECIAL (_AT(pteval_t, 1) << 56)
ARM: mm: introduce present, faulting entries for PAGE_NONE PROT_NONE mappings apply the page protection attributes defined by _P000 which translate to PAGE_NONE for ARM. These attributes specify an XN, RDONLY pte that is inaccessible to userspace. However, on kernels configured without support for domains, such a pte *is* accessible to the kernel and can be read via get_user, allowing tasks to read PROT_NONE pages via syscalls such as read/write over a pipe. This patch introduces a new software pte flag, L_PTE_NONE, that is set to identify faulting, present entries. Signed-off-by: Will Deacon <will.deacon@arm.com>
2012-09-01 05:22:12 +01:00
#define L_PTE_NONE (_AT(pteval_t, 1) << 57) /* PROT_NONE */
ARM: 8109/1: mm: Modify pte_write and pmd_write logic for LPAE For LPAE, we have the following means for encoding writable or dirty ptes: L_PTE_DIRTY L_PTE_RDONLY !pte_dirty && !pte_write 0 1 !pte_dirty && pte_write 0 1 pte_dirty && !pte_write 1 1 pte_dirty && pte_write 1 0 So we can't distinguish between writeable clean ptes and read only ptes. This can cause problems with ptes being incorrectly flagged as read only when they are writeable but not dirty. This patch renumbers L_PTE_RDONLY from AP[2] to a software bit #58, and adds additional logic to set AP[2] whenever the pte is read only or not dirty. That way we can distinguish between clean writeable ptes and read only ptes. HugeTLB pages will use this new logic automatically. We need to add some logic to Transparent HugePages to ensure that they correctly interpret the revised pgprot permissions (L_PTE_RDONLY has moved and no longer matches PMD_SECT_AP2). In the process of revising THP, the names of the PMD software bits have been prefixed with L_ to make them easier to distinguish from their hardware bit counterparts. Signed-off-by: Steve Capper <steve.capper@linaro.org> Reviewed-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-07-18 16:16:15 +01:00
#define L_PTE_RDONLY (_AT(pteval_t, 1) << 58) /* READ ONLY */
ARM: LPAE: Introduce the 3-level page table format definitions This patch introduces the pgtable-3level*.h files with definitions specific to the LPAE page table format (3 levels of page tables). Each table is 4KB and has 512 64-bit entries. An entry can point to a 40-bit physical address. The young, write and exec software bits share the corresponding hardware bits (negated). Other software bits use spare bits in the PTE. The patch also changes some variable types from unsigned long or int to pteval_t or pgprot_t. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2011-11-22 17:30:29 +00:00
arm/mm: support __HAVE_ARCH_PTE_SWP_EXCLUSIVE Let's support __HAVE_ARCH_PTE_SWP_EXCLUSIVE by stealing one bit from the offset. This reduces the maximum swap space per file to 64 GiB (was 128 GiB). While at it drop the PTE_TYPE_FAULT from __swp_entry_to_pte() which is defined to be 0 and is rather confusing because we should be dealing with "Linux PTEs" not "hardware PTEs". Also, properly mask the type in __swp_entry(). Link: https://lkml.kernel.org/r/20230113171026.582290-5-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-01-13 18:10:04 +01:00
/* We borrow bit 7 to store the exclusive marker in swap PTEs. */
#define L_PTE_SWP_EXCLUSIVE (_AT(pteval_t, 1) << 7)
ARM: 8109/1: mm: Modify pte_write and pmd_write logic for LPAE For LPAE, we have the following means for encoding writable or dirty ptes: L_PTE_DIRTY L_PTE_RDONLY !pte_dirty && !pte_write 0 1 !pte_dirty && pte_write 0 1 pte_dirty && !pte_write 1 1 pte_dirty && pte_write 1 0 So we can't distinguish between writeable clean ptes and read only ptes. This can cause problems with ptes being incorrectly flagged as read only when they are writeable but not dirty. This patch renumbers L_PTE_RDONLY from AP[2] to a software bit #58, and adds additional logic to set AP[2] whenever the pte is read only or not dirty. That way we can distinguish between clean writeable ptes and read only ptes. HugeTLB pages will use this new logic automatically. We need to add some logic to Transparent HugePages to ensure that they correctly interpret the revised pgprot permissions (L_PTE_RDONLY has moved and no longer matches PMD_SECT_AP2). In the process of revising THP, the names of the PMD software bits have been prefixed with L_ to make them easier to distinguish from their hardware bit counterparts. Signed-off-by: Steve Capper <steve.capper@linaro.org> Reviewed-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-07-18 16:16:15 +01:00
#define L_PMD_SECT_VALID (_AT(pmdval_t, 1) << 0)
#define L_PMD_SECT_DIRTY (_AT(pmdval_t, 1) << 55)
#define L_PMD_SECT_NONE (_AT(pmdval_t, 1) << 57)
#define L_PMD_SECT_RDONLY (_AT(pteval_t, 1) << 58)
ARM: mm: Transparent huge page support for LPAE systems. The patch adds support for THP (transparent huge pages) to LPAE systems. When this feature is enabled, the kernel tries to map anonymous pages as 2MB sections where possible. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> [steve.capper@linaro.org: symbolic constants used, value of PMD_SECT_SPLITTING adjusted, tlbflush.h included in pgtable.h, added PROT_NONE support.] Signed-off-by: Steve Capper <steve.capper@linaro.org> Reviewed-by: Will Deacon <will.deacon@arm.com>
2012-07-25 14:39:26 +01:00
ARM: LPAE: Introduce the 3-level page table format definitions This patch introduces the pgtable-3level*.h files with definitions specific to the LPAE page table format (3 levels of page tables). Each table is 4KB and has 512 64-bit entries. An entry can point to a 40-bit physical address. The young, write and exec software bits share the corresponding hardware bits (negated). Other software bits use spare bits in the PTE. The patch also changes some variable types from unsigned long or int to pteval_t or pgprot_t. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2011-11-22 17:30:29 +00:00
/*
* To be used in assembly code with the upper page attributes.
*/
#define L_PTE_XN_HIGH (1 << (54 - 32))
#define L_PTE_DIRTY_HIGH (1 << (55 - 32))
/*
* AttrIndx[2:0] encoding (mapping attributes defined in the MAIR* registers).
*/
#define L_PTE_MT_UNCACHED (_AT(pteval_t, 0) << 2) /* strongly ordered */
#define L_PTE_MT_BUFFERABLE (_AT(pteval_t, 1) << 2) /* normal non-cacheable */
#define L_PTE_MT_WRITETHROUGH (_AT(pteval_t, 2) << 2) /* normal inner write-through */
#define L_PTE_MT_WRITEBACK (_AT(pteval_t, 3) << 2) /* normal inner write-back */
#define L_PTE_MT_WRITEALLOC (_AT(pteval_t, 7) << 2) /* normal inner write-alloc */
#define L_PTE_MT_DEV_SHARED (_AT(pteval_t, 4) << 2) /* device */
#define L_PTE_MT_DEV_NONSHARED (_AT(pteval_t, 4) << 2) /* device */
#define L_PTE_MT_DEV_WC (_AT(pteval_t, 1) << 2) /* normal non-cacheable */
#define L_PTE_MT_DEV_CACHED (_AT(pteval_t, 3) << 2) /* normal inner write-back */
#define L_PTE_MT_MASK (_AT(pteval_t, 7) << 2)
ARM: LPAE: Page table maintenance for the 3-level format This patch modifies the pgd/pmd/pte manipulation functions to support the 3-level page table format. Since there is no need for an 'ext' argument to cpu_set_pte_ext(), this patch conditionally defines a different prototype for this function when CONFIG_ARM_LPAE. The patch also introduces the L_PGD_SWAPPER flag to mark pgd entries pointing to pmd tables pre-allocated in the swapper_pg_dir and avoid trying to free them at run-time. This flag is 0 with the classic page table format. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2011-11-22 17:30:29 +00:00
/*
* Software PGD flags.
*/
#define L_PGD_SWAPPER (_AT(pgdval_t, 1) << 55) /* swapper_pg_dir entry */
#ifndef __ASSEMBLY__
#define pud_none(pud) (!pud_val(pud))
#define pud_bad(pud) (!(pud_val(pud) & 2))
#define pud_present(pud) (pud_val(pud))
ARM: Add page table and page defines needed by KVM KVM uses the stage-2 page tables and the Hyp page table format, so we define the fields and page protection flags needed by KVM. The nomenclature is this: - page_hyp: PL2 code/data mappings - page_hyp_device: PL2 device mappings (vgic access) - page_s2: Stage-2 code/data page mappings - page_s2_device: Stage-2 device mappings (vgic access) Reviewed-by: Will Deacon <will.deacon@arm.com> Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com> Christoffer Dall <c.dall@virtualopensystems.com>
2013-01-20 18:28:04 -05:00
#define pmd_table(pmd) ((pmd_val(pmd) & PMD_TYPE_MASK) == \
PMD_TYPE_TABLE)
#define pmd_sect(pmd) ((pmd_val(pmd) & PMD_TYPE_MASK) == \
PMD_TYPE_SECT)
ARM: add support to dump the kernel page tables This patch allows the kernel page tables to be dumped via a debugfs file, allowing kernel developers to check the layout of the kernel page tables and the verify the various permissions and type settings. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-10-23 16:13:02 +01:00
#define pmd_large(pmd) pmd_sect(pmd)
arm: mm: add p?d_leaf() definitions walk_page_range() is going to be allowed to walk page tables other than those of user space. For this it needs to know when it has reached a 'leaf' entry in the page tables. This information is provided by the p?d_leaf() functions/macros. For arm pmd_large() already exists and does what we want. So simply provide the generic pmd_leaf() name. Link: http://lkml.kernel.org/r/20191218162402.45610-4-steven.price@arm.com Signed-off-by: Steven Price <steven.price@arm.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Alexandre Ghiti <alex@ghiti.fr> Cc: Andy Lutomirski <luto@kernel.org> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David S. Miller <davem@davemloft.net> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Hogan <jhogan@kernel.org> Cc: James Morse <james.morse@arm.com> Cc: Jerome Glisse <jglisse@redhat.com> Cc: "Liang, Kan" <kan.liang@linux.intel.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Paul Burton <paul.burton@mips.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Will Deacon <will@kernel.org> Cc: Zong Li <zong.li@sifive.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-02-03 17:35:10 -08:00
#define pmd_leaf(pmd) pmd_sect(pmd)
ARM: LPAE: Page table maintenance for the 3-level format This patch modifies the pgd/pmd/pte manipulation functions to support the 3-level page table format. Since there is no need for an 'ext' argument to cpu_set_pte_ext(), this patch conditionally defines a different prototype for this function when CONFIG_ARM_LPAE. The patch also introduces the L_PGD_SWAPPER flag to mark pgd entries pointing to pmd tables pre-allocated in the swapper_pg_dir and avoid trying to free them at run-time. This flag is 0 with the classic page table format. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2011-11-22 17:30:29 +00:00
#define pud_clear(pudp) \
do { \
*pudp = __pud(0); \
clean_pmd_entry(pudp); \
} while (0)
#define set_pud(pudp, pud) \
do { \
*pudp = pud; \
flush_pmd_entry(pudp); \
} while (0)
mm: rename pud_page_vaddr to pud_pgtable and make it return pmd_t * No functional change in this patch. [aneesh.kumar@linux.ibm.com: fix] Link: https://lkml.kernel.org/r/87wnqtnb60.fsf@linux.ibm.com [sfr@canb.auug.org.au: another fix] Link: https://lkml.kernel.org/r/20210619134410.89559-1-aneesh.kumar@linux.ibm.com Link: https://lkml.kernel.org/r/20210615110859.320299-1-aneesh.kumar@linux.ibm.com Link: https://lore.kernel.org/linuxppc-dev/CAHk-=wi+J+iodze9FtjM3Zi4j4OeS+qqbKxME9QN4roxPEXH9Q@mail.gmail.com/ Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Hugh Dickins <hughd@google.com> Cc: Joel Fernandes <joel@joelfernandes.org> Cc: Kalesh Singh <kaleshsingh@google.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-07-07 18:09:53 -07:00
static inline pmd_t *pud_pgtable(pud_t pud)
ARM: LPAE: Page table maintenance for the 3-level format This patch modifies the pgd/pmd/pte manipulation functions to support the 3-level page table format. Since there is no need for an 'ext' argument to cpu_set_pte_ext(), this patch conditionally defines a different prototype for this function when CONFIG_ARM_LPAE. The patch also introduces the L_PGD_SWAPPER flag to mark pgd entries pointing to pmd tables pre-allocated in the swapper_pg_dir and avoid trying to free them at run-time. This flag is 0 with the classic page table format. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2011-11-22 17:30:29 +00:00
{
return __va(pud_val(pud) & PHYS_MASK & (s32)PAGE_MASK);
}
#define pmd_bad(pmd) (!(pmd_val(pmd) & 2))
#define copy_pmd(pmdpd,pmdps) \
do { \
*pmdpd = *pmdps; \
flush_pmd_entry(pmdpd); \
} while (0)
#define pmd_clear(pmdp) \
do { \
*pmdp = __pmd(0); \
clean_pmd_entry(pmdp); \
} while (0)
ARM: mm: correct pte_same behaviour for LPAE. For 3 levels of paging the PTE_EXT_NG bit will be set for user address ptes that are written to a page table but not for ptes created with mk_pte. This can cause some comparison tests made by pte_same to fail spuriously and lead to other problems. To correct this behaviour, we mask off PTE_EXT_NG for any pte that is present before running the comparison. Signed-off-by: Steve Capper <steve.capper@linaro.org> Reviewed-by: Will Deacon <will.deacon@arm.com>
2013-05-17 12:32:55 +01:00
/*
* For 3 levels of paging the PTE_EXT_NG bit will be set for user address ptes
* that are written to a page table but not for ptes created with mk_pte.
*
* In hugetlb_no_page, a new huge pte (new_pte) is generated and passed to
* hugetlb_cow, where it is compared with an entry in a page table.
* This comparison test fails erroneously leading ultimately to a memory leak.
*
* To correct this behaviour, we mask off PTE_EXT_NG for any pte that is
* present before running the comparison.
*/
#define __HAVE_ARCH_PTE_SAME
#define pte_same(pte_a,pte_b) ((pte_present(pte_a) ? pte_val(pte_a) & ~PTE_EXT_NG \
: pte_val(pte_a)) \
== (pte_present(pte_b) ? pte_val(pte_b) & ~PTE_EXT_NG \
: pte_val(pte_b)))
ARM: LPAE: Page table maintenance for the 3-level format This patch modifies the pgd/pmd/pte manipulation functions to support the 3-level page table format. Since there is no need for an 'ext' argument to cpu_set_pte_ext(), this patch conditionally defines a different prototype for this function when CONFIG_ARM_LPAE. The patch also introduces the L_PGD_SWAPPER flag to mark pgd entries pointing to pmd tables pre-allocated in the swapper_pg_dir and avoid trying to free them at run-time. This flag is 0 with the classic page table format. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2011-11-22 17:30:29 +00:00
#define set_pte_ext(ptep,pte,ext) cpu_set_pte_ext(ptep,__pte(pte_val(pte)|(ext)))
ARM: mm: HugeTLB support for LPAE systems. This patch adds support for hugetlbfs based on the x86 implementation. It allows mapping of 2MB sections (see Documentation/vm/hugetlbpage.txt for usage). The 64K pages configuration is not supported (section size is 512MB in this case). Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> [steve.capper@linaro.org: symbolic constants replace numbers in places. Split up into multiple files, to simplify future non-LPAE support, removed huge_pmd_share code, as this is very rarely executed, Added PROT_NONE support]. Signed-off-by: Steve Capper <steve.capper@linaro.org> Reviewed-by: Will Deacon <will.deacon@arm.com>
2012-07-25 14:32:38 +01:00
#define pte_huge(pte) (pte_val(pte) && !(pte_val(pte) & PTE_TABLE_BIT))
#define pte_mkhuge(pte) (__pte(pte_val(pte) & ~PTE_TABLE_BIT))
ARM: 8108/1: mm: Introduce {pte,pmd}_isset and {pte,pmd}_isclear Long descriptors on ARM are 64 bits, and some pte functions such as pte_dirty return a bitwise-and of a flag with the pte value. If the flag to be tested resides in the upper 32 bits of the pte, then we run into the danger of the result being dropped if downcast. For example: gather_stats(page, md, pte_dirty(*pte), 1); where pte_dirty(*pte) is downcast to an int. This patch introduces a new macro pte_isset which performs the bitwise and, then performs a double logical invert (where needed) to ensure predictable downcasting. The logical inverse pte_isclear is also introduced. Equivalent pmd functions for Transparent HugePages have also been added. Signed-off-by: Steve Capper <steve.capper@linaro.org> Reviewed-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-07-18 16:15:27 +01:00
#define pmd_isset(pmd, val) ((u32)(val) == (val) ? pmd_val(pmd) & (val) \
: !!(pmd_val(pmd) & (val)))
#define pmd_isclear(pmd, val) (!(pmd_val(pmd) & (val)))
ARM: 8578/1: mm: ensure pmd_present only checks the valid bit In a subsequent patch, pmd_mknotpresent will clear the valid bit of the pmd entry, resulting in a not-present entry from the hardware's perspective. Unfortunately, pmd_present simply checks for a non-zero pmd value and will therefore continue to return true even after a pmd_mknotpresent operation. Since pmd_mknotpresent is only used for managing huge entries, this is only an issue for the 3-level case. This patch fixes the 3-level pmd_present implementation to take into account the valid bit. For bisectability, the change is made before the fix to pmd_mknotpresent. [catalin.marinas@arm.com: comment update regarding pmd_mknotpresent patch] Fixes: 8d9625070073 ("ARM: mm: Transparent huge page support for LPAE systems.") Cc: <stable@vger.kernel.org> # 3.11+ Cc: Russell King <linux@armlinux.org.uk> Cc: Steve Capper <Steve.Capper@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2016-06-07 17:57:54 +01:00
#define pmd_present(pmd) (pmd_isset((pmd), L_PMD_SECT_VALID))
ARM: 8108/1: mm: Introduce {pte,pmd}_isset and {pte,pmd}_isclear Long descriptors on ARM are 64 bits, and some pte functions such as pte_dirty return a bitwise-and of a flag with the pte value. If the flag to be tested resides in the upper 32 bits of the pte, then we run into the danger of the result being dropped if downcast. For example: gather_stats(page, md, pte_dirty(*pte), 1); where pte_dirty(*pte) is downcast to an int. This patch introduces a new macro pte_isset which performs the bitwise and, then performs a double logical invert (where needed) to ensure predictable downcasting. The logical inverse pte_isclear is also introduced. Equivalent pmd functions for Transparent HugePages have also been added. Signed-off-by: Steve Capper <steve.capper@linaro.org> Reviewed-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-07-18 16:15:27 +01:00
#define pmd_young(pmd) (pmd_isset((pmd), PMD_SECT_AF))
arm: mm: introduce special ptes for LPAE We need a mechanism to tag ptes as being special, this indicates that no attempt should be made to access the underlying struct page * associated with the pte. This is used by the fast_gup when operating on ptes as it has no means to access VMAs (that also contain this information) locklessly. The L_PTE_SPECIAL bit is already allocated for LPAE, this patch modifies pte_special and pte_mkspecial to make use of it, and defines __HAVE_ARCH_PTE_SPECIAL. This patch also excludes special ptes from the icache/dcache sync logic. Signed-off-by: Steve Capper <steve.capper@linaro.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Dann Frazier <dann.frazier@canonical.com> Cc: Hugh Dickins <hughd@google.com> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Will Deacon <will.deacon@arm.com> Cc: Christoffer Dall <christoffer.dall@linaro.org> Cc: Andrea Arcangeli <aarcange@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-10-09 15:29:16 -07:00
#define pte_special(pte) (pte_isset((pte), L_PTE_SPECIAL))
static inline pte_t pte_mkspecial(pte_t pte)
{
pte_val(pte) |= L_PTE_SPECIAL;
return pte;
}
ARM: mm: Transparent huge page support for LPAE systems. The patch adds support for THP (transparent huge pages) to LPAE systems. When this feature is enabled, the kernel tries to map anonymous pages as 2MB sections where possible. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> [steve.capper@linaro.org: symbolic constants used, value of PMD_SECT_SPLITTING adjusted, tlbflush.h included in pgtable.h, added PROT_NONE support.] Signed-off-by: Steve Capper <steve.capper@linaro.org> Reviewed-by: Will Deacon <will.deacon@arm.com>
2012-07-25 14:39:26 +01:00
ARM: 8109/1: mm: Modify pte_write and pmd_write logic for LPAE For LPAE, we have the following means for encoding writable or dirty ptes: L_PTE_DIRTY L_PTE_RDONLY !pte_dirty && !pte_write 0 1 !pte_dirty && pte_write 0 1 pte_dirty && !pte_write 1 1 pte_dirty && pte_write 1 0 So we can't distinguish between writeable clean ptes and read only ptes. This can cause problems with ptes being incorrectly flagged as read only when they are writeable but not dirty. This patch renumbers L_PTE_RDONLY from AP[2] to a software bit #58, and adds additional logic to set AP[2] whenever the pte is read only or not dirty. That way we can distinguish between clean writeable ptes and read only ptes. HugeTLB pages will use this new logic automatically. We need to add some logic to Transparent HugePages to ensure that they correctly interpret the revised pgprot permissions (L_PTE_RDONLY has moved and no longer matches PMD_SECT_AP2). In the process of revising THP, the names of the PMD software bits have been prefixed with L_ to make them easier to distinguish from their hardware bit counterparts. Signed-off-by: Steve Capper <steve.capper@linaro.org> Reviewed-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-07-18 16:16:15 +01:00
#define pmd_write(pmd) (pmd_isclear((pmd), L_PMD_SECT_RDONLY))
#define pmd_dirty(pmd) (pmd_isset((pmd), L_PMD_SECT_DIRTY))
ARM: mm: Transparent huge page support for LPAE systems. The patch adds support for THP (transparent huge pages) to LPAE systems. When this feature is enabled, the kernel tries to map anonymous pages as 2MB sections where possible. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> [steve.capper@linaro.org: symbolic constants used, value of PMD_SECT_SPLITTING adjusted, tlbflush.h included in pgtable.h, added PROT_NONE support.] Signed-off-by: Steve Capper <steve.capper@linaro.org> Reviewed-by: Will Deacon <will.deacon@arm.com>
2012-07-25 14:39:26 +01:00
ARM: 7858/1: mm: make UACCESS_WITH_MEMCPY huge page aware The memory pinning code in uaccess_with_memcpy.c does not check for HugeTLB or THP pmds, and will enter an infinite loop should a __copy_to_user or __clear_user occur against a huge page. This patch adds detection code for huge pages to pin_page_for_write. As this code can be executed in a fast path it refers to the actual pmds rather than the vma. If a HugeTLB or THP is found (they have the same pmd representation on ARM), the page table spinlock is taken to prevent modification whilst the page is pinned. On ARM, huge pages are only represented as pmds, thus no huge pud checks are performed. (For huge puds one would lock the page table in a similar manner as in the pmd case). Two helper functions are introduced; pmd_thp_or_huge will check whether or not a page is huge or transparent huge (which have the same pmd layout on ARM), and pmd_hugewillfault will detect whether or not a page fault will occur on write to the page. Running the following test (with the chunking from read_zero removed): $ dd if=/dev/zero of=/dev/null bs=10M count=1024 Gave: 2.3 GB/s backed by normal pages, 2.9 GB/s backed by huge pages, 5.1 GB/s backed by huge pages, with page mask=HPAGE_MASK. After some discussion, it was decided not to adopt the HPAGE_MASK, as this would have a significant detrimental effect on the overall system latency due to page_table_lock being held for too long. This could be revisited if split huge page locks are adopted. Signed-off-by: Steve Capper <steve.capper@linaro.org> Reviewed-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2013-10-14 09:49:10 +01:00
#define pmd_hugewillfault(pmd) (!pmd_young(pmd) || !pmd_write(pmd))
#define pmd_thp_or_huge(pmd) (pmd_huge(pmd) || pmd_trans_huge(pmd))
ARM: mm: Transparent huge page support for LPAE systems. The patch adds support for THP (transparent huge pages) to LPAE systems. When this feature is enabled, the kernel tries to map anonymous pages as 2MB sections where possible. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> [steve.capper@linaro.org: symbolic constants used, value of PMD_SECT_SPLITTING adjusted, tlbflush.h included in pgtable.h, added PROT_NONE support.] Signed-off-by: Steve Capper <steve.capper@linaro.org> Reviewed-by: Will Deacon <will.deacon@arm.com>
2012-07-25 14:39:26 +01:00
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
ARM: 8108/1: mm: Introduce {pte,pmd}_isset and {pte,pmd}_isclear Long descriptors on ARM are 64 bits, and some pte functions such as pte_dirty return a bitwise-and of a flag with the pte value. If the flag to be tested resides in the upper 32 bits of the pte, then we run into the danger of the result being dropped if downcast. For example: gather_stats(page, md, pte_dirty(*pte), 1); where pte_dirty(*pte) is downcast to an int. This patch introduces a new macro pte_isset which performs the bitwise and, then performs a double logical invert (where needed) to ensure predictable downcasting. The logical inverse pte_isclear is also introduced. Equivalent pmd functions for Transparent HugePages have also been added. Signed-off-by: Steve Capper <steve.capper@linaro.org> Reviewed-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-07-18 16:15:27 +01:00
#define pmd_trans_huge(pmd) (pmd_val(pmd) && !pmd_table(pmd))
ARM: mm: Transparent huge page support for LPAE systems. The patch adds support for THP (transparent huge pages) to LPAE systems. When this feature is enabled, the kernel tries to map anonymous pages as 2MB sections where possible. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> [steve.capper@linaro.org: symbolic constants used, value of PMD_SECT_SPLITTING adjusted, tlbflush.h included in pgtable.h, added PROT_NONE support.] Signed-off-by: Steve Capper <steve.capper@linaro.org> Reviewed-by: Will Deacon <will.deacon@arm.com>
2012-07-25 14:39:26 +01:00
#endif
#define PMD_BIT_FUNC(fn,op) \
static inline pmd_t pmd_##fn(pmd_t pmd) { pmd_val(pmd) op; return pmd; }
ARM: 8109/1: mm: Modify pte_write and pmd_write logic for LPAE For LPAE, we have the following means for encoding writable or dirty ptes: L_PTE_DIRTY L_PTE_RDONLY !pte_dirty && !pte_write 0 1 !pte_dirty && pte_write 0 1 pte_dirty && !pte_write 1 1 pte_dirty && pte_write 1 0 So we can't distinguish between writeable clean ptes and read only ptes. This can cause problems with ptes being incorrectly flagged as read only when they are writeable but not dirty. This patch renumbers L_PTE_RDONLY from AP[2] to a software bit #58, and adds additional logic to set AP[2] whenever the pte is read only or not dirty. That way we can distinguish between clean writeable ptes and read only ptes. HugeTLB pages will use this new logic automatically. We need to add some logic to Transparent HugePages to ensure that they correctly interpret the revised pgprot permissions (L_PTE_RDONLY has moved and no longer matches PMD_SECT_AP2). In the process of revising THP, the names of the PMD software bits have been prefixed with L_ to make them easier to distinguish from their hardware bit counterparts. Signed-off-by: Steve Capper <steve.capper@linaro.org> Reviewed-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-07-18 16:16:15 +01:00
PMD_BIT_FUNC(wrprotect, |= L_PMD_SECT_RDONLY);
ARM: mm: Transparent huge page support for LPAE systems. The patch adds support for THP (transparent huge pages) to LPAE systems. When this feature is enabled, the kernel tries to map anonymous pages as 2MB sections where possible. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> [steve.capper@linaro.org: symbolic constants used, value of PMD_SECT_SPLITTING adjusted, tlbflush.h included in pgtable.h, added PROT_NONE support.] Signed-off-by: Steve Capper <steve.capper@linaro.org> Reviewed-by: Will Deacon <will.deacon@arm.com>
2012-07-25 14:39:26 +01:00
PMD_BIT_FUNC(mkold, &= ~PMD_SECT_AF);
ARM: 8109/1: mm: Modify pte_write and pmd_write logic for LPAE For LPAE, we have the following means for encoding writable or dirty ptes: L_PTE_DIRTY L_PTE_RDONLY !pte_dirty && !pte_write 0 1 !pte_dirty && pte_write 0 1 pte_dirty && !pte_write 1 1 pte_dirty && pte_write 1 0 So we can't distinguish between writeable clean ptes and read only ptes. This can cause problems with ptes being incorrectly flagged as read only when they are writeable but not dirty. This patch renumbers L_PTE_RDONLY from AP[2] to a software bit #58, and adds additional logic to set AP[2] whenever the pte is read only or not dirty. That way we can distinguish between clean writeable ptes and read only ptes. HugeTLB pages will use this new logic automatically. We need to add some logic to Transparent HugePages to ensure that they correctly interpret the revised pgprot permissions (L_PTE_RDONLY has moved and no longer matches PMD_SECT_AP2). In the process of revising THP, the names of the PMD software bits have been prefixed with L_ to make them easier to distinguish from their hardware bit counterparts. Signed-off-by: Steve Capper <steve.capper@linaro.org> Reviewed-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-07-18 16:16:15 +01:00
PMD_BIT_FUNC(mkwrite, &= ~L_PMD_SECT_RDONLY);
PMD_BIT_FUNC(mkdirty, |= L_PMD_SECT_DIRTY);
arch/arm/include/asm/pgtable-3level.h: add pmd_mkclean for THP MADV_FREE needs pmd_dirty and pmd_mkclean for detecting recent overwrite of the contents since MADV_FREE syscall is called for THP page. This patch adds pmd_mkclean for THP page MADV_FREE support. Signed-off-by: Minchan Kim <minchan@kernel.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Russell King <rmk@arm.linux.org.uk> Cc: "James E.J. Bottomley" <jejb@parisc-linux.org> Cc: "Kirill A. Shutemov" <kirill@shutemov.name> Cc: Shaohua Li <shli@kernel.org> Cc: <yalin.wang2010@gmail.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Chen Gang <gang.chen.5i5j@gmail.com> Cc: Chris Zankel <chris@zankel.net> Cc: Daniel Micay <danielmicay@gmail.com> Cc: Darrick J. Wong <darrick.wong@oracle.com> Cc: David S. Miller <davem@davemloft.net> Cc: Helge Deller <deller@gmx.de> Cc: Hugh Dickins <hughd@google.com> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Jason Evans <je@fb.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Kirill A. Shutemov <kirill@shutemov.name> Cc: Matt Turner <mattst88@gmail.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Michael Kerrisk <mtk.manpages@gmail.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Mika Penttil <mika.penttila@nextfour.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Richard Henderson <rth@twiddle.net> Cc: Rik van Riel <riel@redhat.com> Cc: Roland Dreier <roland@kernel.org> Cc: Shaohua Li <shli@kernel.org> Cc: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-15 16:55:33 -08:00
PMD_BIT_FUNC(mkclean, &= ~L_PMD_SECT_DIRTY);
ARM: mm: Transparent huge page support for LPAE systems. The patch adds support for THP (transparent huge pages) to LPAE systems. When this feature is enabled, the kernel tries to map anonymous pages as 2MB sections where possible. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> [steve.capper@linaro.org: symbolic constants used, value of PMD_SECT_SPLITTING adjusted, tlbflush.h included in pgtable.h, added PROT_NONE support.] Signed-off-by: Steve Capper <steve.capper@linaro.org> Reviewed-by: Will Deacon <will.deacon@arm.com>
2012-07-25 14:39:26 +01:00
PMD_BIT_FUNC(mkyoung, |= PMD_SECT_AF);
#define pmd_mkhuge(pmd) (__pmd(pmd_val(pmd) & ~PMD_TABLE_BIT))
#define pmd_pfn(pmd) (((pmd_val(pmd) & PMD_MASK) & PHYS_MASK) >> PAGE_SHIFT)
#define pfn_pmd(pfn,prot) (__pmd(((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot)))
#define mk_pmd(page,prot) pfn_pmd(page_to_pfn(page),prot)
arm/mm: provide pmdp_establish() helper ARM LPAE doesn't have hardware dirty/accessed bits. generic_pmdp_establish() is the right implementation of pmdp_establish for this case. Link: http://lkml.kernel.org/r/20171213105756.69879-4-kirill.shutemov@linux.intel.com Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Michal Hocko <mhocko@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-01-31 16:17:51 -08:00
/* No hardware dirty/accessed bits -- generic_pmdp_establish() fits */
#define pmdp_establish generic_pmdp_establish
ARM: 8579/1: mm: Fix definition of pmd_mknotpresent Currently pmd_mknotpresent will use a zero entry to respresent an invalidated pmd. Unfortunately this definition clashes with pmd_none, thus it is possible for a race condition to occur if zap_pmd_range sees pmd_none whilst __split_huge_pmd_locked is running too with pmdp_invalidate just called. This patch fixes the race condition by modifying pmd_mknotpresent to create non-zero faulting entries (as is done in other architectures), removing the ambiguity with pmd_none. [catalin.marinas@arm.com: using L_PMD_SECT_VALID instead of PMD_TYPE_SECT] Fixes: 8d9625070073 ("ARM: mm: Transparent huge page support for LPAE systems.") Cc: <stable@vger.kernel.org> # 3.11+ Reported-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Will Deacon <will.deacon@arm.com> Cc: Russell King <linux@armlinux.org.uk> Signed-off-by: Steve Capper <steve.capper@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2016-06-07 17:58:06 +01:00
/* represent a notpresent pmd by faulting entry, this is used by pmdp_invalidate */
mm/thp: rename pmd_mknotpresent() as pmd_mkinvalid() pmd_present() is expected to test positive after pmdp_mknotpresent() as the PMD entry still points to a valid huge page in memory. pmdp_mknotpresent() implies that given PMD entry is just invalidated from MMU perspective while still holding on to pmd_page() referred valid huge page thus also clearing pmd_present() test. This creates the following situation which is counter intuitive. [pmd_present(pmd_mknotpresent(pmd)) = true] This renames pmd_mknotpresent() as pmd_mkinvalid() reflecting the helper's functionality more accurately while changing the above mentioned situation as follows. This does not create any functional change. [pmd_present(pmd_mkinvalid(pmd)) = true] This is not applicable for platforms that define own pmdp_invalidate() via __HAVE_ARCH_PMDP_INVALIDATE. Suggestion for renaming came during a previous discussion here. https://patchwork.kernel.org/patch/11019637/ [anshuman.khandual@arm.com: change pmd_mknotvalid() to pmd_mkinvalid() per Will] Link: http://lkml.kernel.org/r/1587520326-10099-3-git-send-email-anshuman.khandual@arm.com Suggested-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Will Deacon <will@kernel.org> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Paul Mackerras <paulus@samba.org> Link: http://lkml.kernel.org/r/1584680057-13753-3-git-send-email-anshuman.khandual@arm.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-03 16:03:45 -07:00
static inline pmd_t pmd_mkinvalid(pmd_t pmd)
mm: convert p[te|md]_mknonnuma and remaining page table manipulations With PROT_NONE, the traditional page table manipulation functions are sufficient. [andre.przywara@arm.com: fix compiler warning in pmdp_invalidate()] [akpm@linux-foundation.org: fix build with STRICT_MM_TYPECHECKS] Signed-off-by: Mel Gorman <mgorman@suse.de> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Aneesh Kumar <aneesh.kumar@linux.vnet.ibm.com> Tested-by: Sasha Levin <sasha.levin@oracle.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Dave Jones <davej@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Kirill Shutemov <kirill.shutemov@linux.intel.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-12 14:58:28 -08:00
{
ARM: 8579/1: mm: Fix definition of pmd_mknotpresent Currently pmd_mknotpresent will use a zero entry to respresent an invalidated pmd. Unfortunately this definition clashes with pmd_none, thus it is possible for a race condition to occur if zap_pmd_range sees pmd_none whilst __split_huge_pmd_locked is running too with pmdp_invalidate just called. This patch fixes the race condition by modifying pmd_mknotpresent to create non-zero faulting entries (as is done in other architectures), removing the ambiguity with pmd_none. [catalin.marinas@arm.com: using L_PMD_SECT_VALID instead of PMD_TYPE_SECT] Fixes: 8d9625070073 ("ARM: mm: Transparent huge page support for LPAE systems.") Cc: <stable@vger.kernel.org> # 3.11+ Reported-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Will Deacon <will.deacon@arm.com> Cc: Russell King <linux@armlinux.org.uk> Signed-off-by: Steve Capper <steve.capper@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2016-06-07 17:58:06 +01:00
return __pmd(pmd_val(pmd) & ~L_PMD_SECT_VALID);
mm: convert p[te|md]_mknonnuma and remaining page table manipulations With PROT_NONE, the traditional page table manipulation functions are sufficient. [andre.przywara@arm.com: fix compiler warning in pmdp_invalidate()] [akpm@linux-foundation.org: fix build with STRICT_MM_TYPECHECKS] Signed-off-by: Mel Gorman <mgorman@suse.de> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Aneesh Kumar <aneesh.kumar@linux.vnet.ibm.com> Tested-by: Sasha Levin <sasha.levin@oracle.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Dave Jones <davej@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Kirill Shutemov <kirill.shutemov@linux.intel.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-12 14:58:28 -08:00
}
ARM: mm: Transparent huge page support for LPAE systems. The patch adds support for THP (transparent huge pages) to LPAE systems. When this feature is enabled, the kernel tries to map anonymous pages as 2MB sections where possible. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> [steve.capper@linaro.org: symbolic constants used, value of PMD_SECT_SPLITTING adjusted, tlbflush.h included in pgtable.h, added PROT_NONE support.] Signed-off-by: Steve Capper <steve.capper@linaro.org> Reviewed-by: Will Deacon <will.deacon@arm.com>
2012-07-25 14:39:26 +01:00
static inline pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot)
{
ARM: 8109/1: mm: Modify pte_write and pmd_write logic for LPAE For LPAE, we have the following means for encoding writable or dirty ptes: L_PTE_DIRTY L_PTE_RDONLY !pte_dirty && !pte_write 0 1 !pte_dirty && pte_write 0 1 pte_dirty && !pte_write 1 1 pte_dirty && pte_write 1 0 So we can't distinguish between writeable clean ptes and read only ptes. This can cause problems with ptes being incorrectly flagged as read only when they are writeable but not dirty. This patch renumbers L_PTE_RDONLY from AP[2] to a software bit #58, and adds additional logic to set AP[2] whenever the pte is read only or not dirty. That way we can distinguish between clean writeable ptes and read only ptes. HugeTLB pages will use this new logic automatically. We need to add some logic to Transparent HugePages to ensure that they correctly interpret the revised pgprot permissions (L_PTE_RDONLY has moved and no longer matches PMD_SECT_AP2). In the process of revising THP, the names of the PMD software bits have been prefixed with L_ to make them easier to distinguish from their hardware bit counterparts. Signed-off-by: Steve Capper <steve.capper@linaro.org> Reviewed-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-07-18 16:16:15 +01:00
const pmdval_t mask = PMD_SECT_USER | PMD_SECT_XN | L_PMD_SECT_RDONLY |
L_PMD_SECT_VALID | L_PMD_SECT_NONE;
ARM: mm: Transparent huge page support for LPAE systems. The patch adds support for THP (transparent huge pages) to LPAE systems. When this feature is enabled, the kernel tries to map anonymous pages as 2MB sections where possible. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> [steve.capper@linaro.org: symbolic constants used, value of PMD_SECT_SPLITTING adjusted, tlbflush.h included in pgtable.h, added PROT_NONE support.] Signed-off-by: Steve Capper <steve.capper@linaro.org> Reviewed-by: Will Deacon <will.deacon@arm.com>
2012-07-25 14:39:26 +01:00
pmd_val(pmd) = (pmd_val(pmd) & ~mask) | (pgprot_val(newprot) & mask);
return pmd;
}
static inline void set_pmd_at(struct mm_struct *mm, unsigned long addr,
pmd_t *pmdp, pmd_t pmd)
{
BUG_ON(addr >= TASK_SIZE);
/* create a faulting entry if PROT_NONE protected */
ARM: 8109/1: mm: Modify pte_write and pmd_write logic for LPAE For LPAE, we have the following means for encoding writable or dirty ptes: L_PTE_DIRTY L_PTE_RDONLY !pte_dirty && !pte_write 0 1 !pte_dirty && pte_write 0 1 pte_dirty && !pte_write 1 1 pte_dirty && pte_write 1 0 So we can't distinguish between writeable clean ptes and read only ptes. This can cause problems with ptes being incorrectly flagged as read only when they are writeable but not dirty. This patch renumbers L_PTE_RDONLY from AP[2] to a software bit #58, and adds additional logic to set AP[2] whenever the pte is read only or not dirty. That way we can distinguish between clean writeable ptes and read only ptes. HugeTLB pages will use this new logic automatically. We need to add some logic to Transparent HugePages to ensure that they correctly interpret the revised pgprot permissions (L_PTE_RDONLY has moved and no longer matches PMD_SECT_AP2). In the process of revising THP, the names of the PMD software bits have been prefixed with L_ to make them easier to distinguish from their hardware bit counterparts. Signed-off-by: Steve Capper <steve.capper@linaro.org> Reviewed-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-07-18 16:16:15 +01:00
if (pmd_val(pmd) & L_PMD_SECT_NONE)
pmd_val(pmd) &= ~L_PMD_SECT_VALID;
if (pmd_write(pmd) && pmd_dirty(pmd))
pmd_val(pmd) &= ~PMD_SECT_AP2;
else
pmd_val(pmd) |= PMD_SECT_AP2;
ARM: mm: Transparent huge page support for LPAE systems. The patch adds support for THP (transparent huge pages) to LPAE systems. When this feature is enabled, the kernel tries to map anonymous pages as 2MB sections where possible. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> [steve.capper@linaro.org: symbolic constants used, value of PMD_SECT_SPLITTING adjusted, tlbflush.h included in pgtable.h, added PROT_NONE support.] Signed-off-by: Steve Capper <steve.capper@linaro.org> Reviewed-by: Will Deacon <will.deacon@arm.com>
2012-07-25 14:39:26 +01:00
*pmdp = __pmd(pmd_val(pmd) | PMD_SECT_nG);
flush_pmd_entry(pmdp);
}
ARM: LPAE: Page table maintenance for the 3-level format This patch modifies the pgd/pmd/pte manipulation functions to support the 3-level page table format. Since there is no need for an 'ext' argument to cpu_set_pte_ext(), this patch conditionally defines a different prototype for this function when CONFIG_ARM_LPAE. The patch also introduces the L_PGD_SWAPPER flag to mark pgd entries pointing to pmd tables pre-allocated in the swapper_pg_dir and avoid trying to free them at run-time. This flag is 0 with the classic page table format. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2011-11-22 17:30:29 +00:00
#endif /* __ASSEMBLY__ */
ARM: LPAE: Introduce the 3-level page table format definitions This patch introduces the pgtable-3level*.h files with definitions specific to the LPAE page table format (3 levels of page tables). Each table is 4KB and has 512 64-bit entries. An entry can point to a 40-bit physical address. The young, write and exec software bits share the corresponding hardware bits (negated). Other software bits use spare bits in the PTE. The patch also changes some variable types from unsigned long or int to pteval_t or pgprot_t. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2011-11-22 17:30:29 +00:00
#endif /* _ASM_PGTABLE_3LEVEL_H */
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