/* SPDX-License-Identifier: GPL-2.0 */
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#ifndef _LINUX_MM_TYPES_H
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#define _LINUX_MM_TYPES_H
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#include <linux/mm_types_task.h>
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#include <linux/auxvec.h>
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#include <linux/list.h>
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#include <linux/spinlock.h>
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#include <linux/rbtree.h>
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#include <linux/rwsem.h>
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#include <linux/completion.h>
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#include <linux/cpumask.h>
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#include <linux/uprobes.h>
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#include <linux/page-flags-layout.h>
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#include <linux/workqueue.h>
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#include <linux/seqlock.h>
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#include <linux/android_kabi.h>
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#include <asm/mmu.h>
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#include <dovetail/mm_info.h>
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#ifndef AT_VECTOR_SIZE_ARCH
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#define AT_VECTOR_SIZE_ARCH 0
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#endif
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#define AT_VECTOR_SIZE (2*(AT_VECTOR_SIZE_ARCH + AT_VECTOR_SIZE_BASE + 1))
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#define INIT_PASID 0
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struct address_space;
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struct mem_cgroup;
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/*
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* Each physical page in the system has a struct page associated with
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* it to keep track of whatever it is we are using the page for at the
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* moment. Note that we have no way to track which tasks are using
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* a page, though if it is a pagecache page, rmap structures can tell us
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* who is mapping it.
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*
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* If you allocate the page using alloc_pages(), you can use some of the
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* space in struct page for your own purposes. The five words in the main
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* union are available, except for bit 0 of the first word which must be
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* kept clear. Many users use this word to store a pointer to an object
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* which is guaranteed to be aligned. If you use the same storage as
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* page->mapping, you must restore it to NULL before freeing the page.
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*
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* If your page will not be mapped to userspace, you can also use the four
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* bytes in the mapcount union, but you must call page_mapcount_reset()
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* before freeing it.
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*
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* If you want to use the refcount field, it must be used in such a way
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* that other CPUs temporarily incrementing and then decrementing the
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* refcount does not cause problems. On receiving the page from
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* alloc_pages(), the refcount will be positive.
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*
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* If you allocate pages of order > 0, you can use some of the fields
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* in each subpage, but you may need to restore some of their values
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* afterwards.
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*
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* SLUB uses cmpxchg_double() to atomically update its freelist and
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* counters. That requires that freelist & counters be adjacent and
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* double-word aligned. We align all struct pages to double-word
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* boundaries, and ensure that 'freelist' is aligned within the
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* struct.
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*/
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#ifdef CONFIG_HAVE_ALIGNED_STRUCT_PAGE
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#define _struct_page_alignment __aligned(2 * sizeof(unsigned long))
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#else
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#define _struct_page_alignment
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#endif
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struct page {
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unsigned long flags; /* Atomic flags, some possibly
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* updated asynchronously */
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/*
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* Five words (20/40 bytes) are available in this union.
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* WARNING: bit 0 of the first word is used for PageTail(). That
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* means the other users of this union MUST NOT use the bit to
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* avoid collision and false-positive PageTail().
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*/
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union {
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struct { /* Page cache and anonymous pages */
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/**
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* @lru: Pageout list, eg. active_list protected by
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* pgdat->lru_lock. Sometimes used as a generic list
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* by the page owner.
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*/
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struct list_head lru;
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/* See page-flags.h for PAGE_MAPPING_FLAGS */
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struct address_space *mapping;
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pgoff_t index; /* Our offset within mapping. */
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/**
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* @private: Mapping-private opaque data.
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* Usually used for buffer_heads if PagePrivate.
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* Used for swp_entry_t if PageSwapCache.
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* Indicates order in the buddy system if PageBuddy.
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*/
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unsigned long private;
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};
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struct { /* page_pool used by netstack */
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/**
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* @dma_addr: might require a 64-bit value on
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* 32-bit architectures.
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*/
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unsigned long dma_addr[2];
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};
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struct { /* slab, slob and slub */
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union {
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struct list_head slab_list;
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struct { /* Partial pages */
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struct page *next;
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#ifdef CONFIG_64BIT
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int pages; /* Nr of pages left */
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int pobjects; /* Approximate count */
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#else
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short int pages;
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short int pobjects;
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#endif
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};
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};
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struct kmem_cache *slab_cache; /* not slob */
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/* Double-word boundary */
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void *freelist; /* first free object */
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union {
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void *s_mem; /* slab: first object */
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unsigned long counters; /* SLUB */
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struct { /* SLUB */
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unsigned inuse:16;
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unsigned objects:15;
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unsigned frozen:1;
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};
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};
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};
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struct { /* Tail pages of compound page */
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unsigned long compound_head; /* Bit zero is set */
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/* First tail page only */
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unsigned char compound_dtor;
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unsigned char compound_order;
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atomic_t compound_mapcount;
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unsigned int compound_nr; /* 1 << compound_order */
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};
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struct { /* Second tail page of compound page */
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unsigned long _compound_pad_1; /* compound_head */
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atomic_t hpage_pinned_refcount;
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/* For both global and memcg */
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struct list_head deferred_list;
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};
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struct { /* Page table pages */
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unsigned long _pt_pad_1; /* compound_head */
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pgtable_t pmd_huge_pte; /* protected by page->ptl */
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unsigned long _pt_pad_2; /* mapping */
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union {
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struct mm_struct *pt_mm; /* x86 pgds only */
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atomic_t pt_frag_refcount; /* powerpc */
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};
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#if ALLOC_SPLIT_PTLOCKS
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spinlock_t *ptl;
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#else
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spinlock_t ptl;
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#endif
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};
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struct { /* ZONE_DEVICE pages */
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/** @pgmap: Points to the hosting device page map. */
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struct dev_pagemap *pgmap;
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void *zone_device_data;
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/*
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* ZONE_DEVICE private pages are counted as being
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* mapped so the next 3 words hold the mapping, index,
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* and private fields from the source anonymous or
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* page cache page while the page is migrated to device
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* private memory.
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* ZONE_DEVICE MEMORY_DEVICE_FS_DAX pages also
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* use the mapping, index, and private fields when
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* pmem backed DAX files are mapped.
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*/
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};
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/** @rcu_head: You can use this to free a page by RCU. */
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struct rcu_head rcu_head;
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};
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union { /* This union is 4 bytes in size. */
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/*
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* If the page can be mapped to userspace, encodes the number
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* of times this page is referenced by a page table.
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*/
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atomic_t _mapcount;
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/*
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* If the page is neither PageSlab nor mappable to userspace,
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* the value stored here may help determine what this page
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* is used for. See page-flags.h for a list of page types
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* which are currently stored here.
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*/
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unsigned int page_type;
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unsigned int active; /* SLAB */
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int units; /* SLOB */
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};
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/* Usage count. *DO NOT USE DIRECTLY*. See page_ref.h */
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atomic_t _refcount;
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#ifdef CONFIG_MEMCG
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union {
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struct mem_cgroup *mem_cgroup;
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struct obj_cgroup **obj_cgroups;
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};
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#endif
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/*
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* On machines where all RAM is mapped into kernel address space,
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* we can simply calculate the virtual address. On machines with
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* highmem some memory is mapped into kernel virtual memory
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* dynamically, so we need a place to store that address.
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* Note that this field could be 16 bits on x86 ... ;)
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*
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* Architectures with slow multiplication can define
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* WANT_PAGE_VIRTUAL in asm/page.h
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*/
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#if defined(WANT_PAGE_VIRTUAL)
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void *virtual; /* Kernel virtual address (NULL if
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not kmapped, ie. highmem) */
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#endif /* WANT_PAGE_VIRTUAL */
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#ifdef LAST_CPUPID_NOT_IN_PAGE_FLAGS
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int _last_cpupid;
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#endif
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} _struct_page_alignment;
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static inline atomic_t *compound_mapcount_ptr(struct page *page)
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{
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return &page[1].compound_mapcount;
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}
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static inline atomic_t *compound_pincount_ptr(struct page *page)
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{
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return &page[2].hpage_pinned_refcount;
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}
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/*
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* Used for sizing the vmemmap region on some architectures
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*/
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#define STRUCT_PAGE_MAX_SHIFT (order_base_2(sizeof(struct page)))
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#define PAGE_FRAG_CACHE_MAX_SIZE __ALIGN_MASK(32768, ~PAGE_MASK)
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#define PAGE_FRAG_CACHE_MAX_ORDER get_order(PAGE_FRAG_CACHE_MAX_SIZE)
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#define page_private(page) ((page)->private)
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static inline void set_page_private(struct page *page, unsigned long private)
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{
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page->private = private;
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}
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struct page_frag_cache {
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void * va;
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#if (PAGE_SIZE < PAGE_FRAG_CACHE_MAX_SIZE)
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__u16 offset;
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__u16 size;
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#else
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__u32 offset;
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#endif
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/* we maintain a pagecount bias, so that we dont dirty cache line
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* containing page->_refcount every time we allocate a fragment.
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*/
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unsigned int pagecnt_bias;
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bool pfmemalloc;
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};
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typedef unsigned long vm_flags_t;
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/*
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* A region containing a mapping of a non-memory backed file under NOMMU
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* conditions. These are held in a global tree and are pinned by the VMAs that
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* map parts of them.
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*/
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struct vm_region {
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struct rb_node vm_rb; /* link in global region tree */
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vm_flags_t vm_flags; /* VMA vm_flags */
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unsigned long vm_start; /* start address of region */
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unsigned long vm_end; /* region initialised to here */
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unsigned long vm_top; /* region allocated to here */
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unsigned long vm_pgoff; /* the offset in vm_file corresponding to vm_start */
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struct file *vm_file; /* the backing file or NULL */
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int vm_usage; /* region usage count (access under nommu_region_sem) */
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bool vm_icache_flushed : 1; /* true if the icache has been flushed for
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* this region */
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};
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#ifdef CONFIG_USERFAULTFD
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#define NULL_VM_UFFD_CTX ((struct vm_userfaultfd_ctx) { NULL, })
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struct vm_userfaultfd_ctx {
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struct userfaultfd_ctx *ctx;
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};
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#else /* CONFIG_USERFAULTFD */
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#define NULL_VM_UFFD_CTX ((struct vm_userfaultfd_ctx) {})
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struct vm_userfaultfd_ctx {};
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#endif /* CONFIG_USERFAULTFD */
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/*
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* This struct describes a virtual memory area. There is one of these
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* per VM-area/task. A VM area is any part of the process virtual memory
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* space that has a special rule for the page-fault handlers (ie a shared
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* library, the executable area etc).
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*/
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struct vm_area_struct {
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/* The first cache line has the info for VMA tree walking. */
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unsigned long vm_start; /* Our start address within vm_mm. */
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unsigned long vm_end; /* The first byte after our end address
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within vm_mm. */
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/* linked list of VM areas per task, sorted by address */
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struct vm_area_struct *vm_next, *vm_prev;
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struct rb_node vm_rb;
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/*
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* Largest free memory gap in bytes to the left of this VMA.
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* Either between this VMA and vma->vm_prev, or between one of the
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* VMAs below us in the VMA rbtree and its ->vm_prev. This helps
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* get_unmapped_area find a free area of the right size.
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*/
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unsigned long rb_subtree_gap;
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/* Second cache line starts here. */
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struct mm_struct *vm_mm; /* The address space we belong to. */
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/*
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* Access permissions of this VMA.
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* See vmf_insert_mixed_prot() for discussion.
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*/
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pgprot_t vm_page_prot;
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unsigned long vm_flags; /* Flags, see mm.h. */
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/*
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* For areas with an address space and backing store,
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* linkage into the address_space->i_mmap interval tree.
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*
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* For private anonymous mappings, a pointer to a null terminated string
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* in the user process containing the name given to the vma, or NULL
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* if unnamed.
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*/
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union {
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struct {
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struct rb_node rb;
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unsigned long rb_subtree_last;
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} shared;
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const char __user *anon_name;
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};
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/*
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* A file's MAP_PRIVATE vma can be in both i_mmap tree and anon_vma
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* list, after a COW of one of the file pages. A MAP_SHARED vma
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* can only be in the i_mmap tree. An anonymous MAP_PRIVATE, stack
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* or brk vma (with NULL file) can only be in an anon_vma list.
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*/
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struct list_head anon_vma_chain; /* Serialized by mmap_lock &
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* page_table_lock */
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struct anon_vma *anon_vma; /* Serialized by page_table_lock */
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/* Function pointers to deal with this struct. */
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const struct vm_operations_struct *vm_ops;
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/* Information about our backing store: */
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unsigned long vm_pgoff; /* Offset (within vm_file) in PAGE_SIZE
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units */
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struct file * vm_file; /* File we map to (can be NULL). */
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void * vm_private_data; /* was vm_pte (shared mem) */
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#ifdef CONFIG_SWAP
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atomic_long_t swap_readahead_info;
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#endif
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#ifndef CONFIG_MMU
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struct vm_region *vm_region; /* NOMMU mapping region */
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#endif
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#ifdef CONFIG_NUMA
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struct mempolicy *vm_policy; /* NUMA policy for the VMA */
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#endif
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struct vm_userfaultfd_ctx vm_userfaultfd_ctx;
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#ifdef CONFIG_SPECULATIVE_PAGE_FAULT
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seqcount_t vm_sequence;
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atomic_t vm_ref_count; /* see vma_get(), vma_put() */
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#endif
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ANDROID_KABI_RESERVE(1);
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ANDROID_KABI_RESERVE(2);
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ANDROID_KABI_RESERVE(3);
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ANDROID_KABI_RESERVE(4);
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} __randomize_layout;
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struct core_thread {
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struct task_struct *task;
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struct core_thread *next;
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};
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struct core_state {
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atomic_t nr_threads;
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struct core_thread dumper;
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struct completion startup;
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};
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struct kioctx_table;
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struct mm_struct {
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struct {
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struct vm_area_struct *mmap; /* list of VMAs */
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struct rb_root mm_rb;
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u64 vmacache_seqnum; /* per-thread vmacache */
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#ifdef CONFIG_SPECULATIVE_PAGE_FAULT
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rwlock_t mm_rb_lock;
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#endif
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#ifdef CONFIG_MMU
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unsigned long (*get_unmapped_area) (struct file *filp,
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unsigned long addr, unsigned long len,
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unsigned long pgoff, unsigned long flags);
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#endif
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unsigned long mmap_base; /* base of mmap area */
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unsigned long mmap_legacy_base; /* base of mmap area in bottom-up allocations */
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#ifdef CONFIG_HAVE_ARCH_COMPAT_MMAP_BASES
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/* Base adresses for compatible mmap() */
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unsigned long mmap_compat_base;
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unsigned long mmap_compat_legacy_base;
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#endif
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unsigned long task_size; /* size of task vm space */
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unsigned long highest_vm_end; /* highest vma end address */
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pgd_t * pgd;
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#ifdef CONFIG_MEMBARRIER
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/**
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* @membarrier_state: Flags controlling membarrier behavior.
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*
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* This field is close to @pgd to hopefully fit in the same
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* cache-line, which needs to be touched by switch_mm().
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*/
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atomic_t membarrier_state;
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#endif
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/**
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* @mm_users: The number of users including userspace.
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*
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* Use mmget()/mmget_not_zero()/mmput() to modify. When this
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* drops to 0 (i.e. when the task exits and there are no other
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* temporary reference holders), we also release a reference on
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* @mm_count (which may then free the &struct mm_struct if
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* @mm_count also drops to 0).
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*/
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atomic_t mm_users;
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/**
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* @mm_count: The number of references to &struct mm_struct
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* (@mm_users count as 1).
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*
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* Use mmgrab()/mmdrop() to modify. When this drops to 0, the
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* &struct mm_struct is freed.
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*/
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atomic_t mm_count;
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/**
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* @has_pinned: Whether this mm has pinned any pages. This can
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* be either replaced in the future by @pinned_vm when it
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* becomes stable, or grow into a counter on its own. We're
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* aggresive on this bit now - even if the pinned pages were
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* unpinned later on, we'll still keep this bit set for the
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* lifecycle of this mm just for simplicity.
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*/
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atomic_t has_pinned;
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#ifdef CONFIG_MMU
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atomic_long_t pgtables_bytes; /* PTE page table pages */
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#endif
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int map_count; /* number of VMAs */
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spinlock_t page_table_lock; /* Protects page tables and some
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* counters
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*/
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/*
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* With some kernel config, the current mmap_lock's offset
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* inside 'mm_struct' is at 0x120, which is very optimal, as
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* its two hot fields 'count' and 'owner' sit in 2 different
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* cachelines, and when mmap_lock is highly contended, both
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* of the 2 fields will be accessed frequently, current layout
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* will help to reduce cache bouncing.
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*
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* So please be careful with adding new fields before
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* mmap_lock, which can easily push the 2 fields into one
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* cacheline.
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*/
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struct rw_semaphore mmap_lock;
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struct list_head mmlist; /* List of maybe swapped mm's. These
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* are globally strung together off
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* init_mm.mmlist, and are protected
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* by mmlist_lock
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*/
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unsigned long hiwater_rss; /* High-watermark of RSS usage */
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unsigned long hiwater_vm; /* High-water virtual memory usage */
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unsigned long total_vm; /* Total pages mapped */
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unsigned long locked_vm; /* Pages that have PG_mlocked set */
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atomic64_t pinned_vm; /* Refcount permanently increased */
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unsigned long data_vm; /* VM_WRITE & ~VM_SHARED & ~VM_STACK */
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unsigned long exec_vm; /* VM_EXEC & ~VM_WRITE & ~VM_STACK */
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unsigned long stack_vm; /* VM_STACK */
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unsigned long def_flags;
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/**
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* @write_protect_seq: Locked when any thread is write
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* protecting pages mapped by this mm to enforce a later COW,
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* for instance during page table copying for fork().
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*/
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seqcount_t write_protect_seq;
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spinlock_t arg_lock; /* protect the below fields */
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unsigned long start_code, end_code, start_data, end_data;
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unsigned long start_brk, brk, start_stack;
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unsigned long arg_start, arg_end, env_start, env_end;
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unsigned long saved_auxv[AT_VECTOR_SIZE]; /* for /proc/PID/auxv */
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/*
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* Special counters, in some configurations protected by the
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* page_table_lock, in other configurations by being atomic.
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*/
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struct mm_rss_stat rss_stat;
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struct linux_binfmt *binfmt;
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/* Architecture-specific MM context */
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mm_context_t context;
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unsigned long flags; /* Must use atomic bitops to access */
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struct core_state *core_state; /* coredumping support */
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#ifdef CONFIG_AIO
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spinlock_t ioctx_lock;
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struct kioctx_table __rcu *ioctx_table;
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#endif
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#ifdef CONFIG_MEMCG
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/*
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* "owner" points to a task that is regarded as the canonical
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* user/owner of this mm. All of the following must be true in
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* order for it to be changed:
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*
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* current == mm->owner
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* current->mm != mm
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* new_owner->mm == mm
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* new_owner->alloc_lock is held
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*/
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struct task_struct __rcu *owner;
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#endif
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struct user_namespace *user_ns;
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/* store ref to file /proc/<pid>/exe symlink points to */
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struct file __rcu *exe_file;
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#ifdef CONFIG_MMU_NOTIFIER
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struct mmu_notifier_subscriptions *notifier_subscriptions;
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#endif
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#if defined(CONFIG_TRANSPARENT_HUGEPAGE) && !USE_SPLIT_PMD_PTLOCKS
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pgtable_t pmd_huge_pte; /* protected by page_table_lock */
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#endif
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#ifdef CONFIG_NUMA_BALANCING
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/*
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* numa_next_scan is the next time that the PTEs will be marked
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* pte_numa. NUMA hinting faults will gather statistics and
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* migrate pages to new nodes if necessary.
|
*/
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unsigned long numa_next_scan;
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/* Restart point for scanning and setting pte_numa */
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unsigned long numa_scan_offset;
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/* numa_scan_seq prevents two threads setting pte_numa */
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int numa_scan_seq;
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#endif
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/*
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* An operation with batched TLB flushing is going on. Anything
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* that can move process memory needs to flush the TLB when
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* moving a PROT_NONE or PROT_NUMA mapped page.
|
*/
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atomic_t tlb_flush_pending;
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#ifdef CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
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/* See flush_tlb_batched_pending() */
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bool tlb_flush_batched;
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#endif
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struct uprobes_state uprobes_state;
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#ifdef CONFIG_HUGETLB_PAGE
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atomic_long_t hugetlb_usage;
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#endif
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#ifdef CONFIG_DOVETAIL
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struct oob_mm_state oob_state;
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#endif
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struct work_struct async_put_work;
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#ifdef CONFIG_IOMMU_SUPPORT
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u32 pasid;
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#endif
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ANDROID_KABI_RESERVE(1);
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} __randomize_layout;
|
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/*
|
* The mm_cpumask needs to be at the end of mm_struct, because it
|
* is dynamically sized based on nr_cpu_ids.
|
*/
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unsigned long cpu_bitmap[];
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};
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extern struct mm_struct init_mm;
|
|
/* Pointer magic because the dynamic array size confuses some compilers. */
|
static inline void mm_init_cpumask(struct mm_struct *mm)
|
{
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unsigned long cpu_bitmap = (unsigned long)mm;
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cpu_bitmap += offsetof(struct mm_struct, cpu_bitmap);
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cpumask_clear((struct cpumask *)cpu_bitmap);
|
}
|
|
/* Future-safe accessor for struct mm_struct's cpu_vm_mask. */
|
static inline cpumask_t *mm_cpumask(struct mm_struct *mm)
|
{
|
return (struct cpumask *)&mm->cpu_bitmap;
|
}
|
|
struct mmu_gather;
|
extern void tlb_gather_mmu(struct mmu_gather *tlb, struct mm_struct *mm,
|
unsigned long start, unsigned long end);
|
extern void tlb_finish_mmu(struct mmu_gather *tlb,
|
unsigned long start, unsigned long end);
|
|
static inline void init_tlb_flush_pending(struct mm_struct *mm)
|
{
|
atomic_set(&mm->tlb_flush_pending, 0);
|
}
|
|
static inline void inc_tlb_flush_pending(struct mm_struct *mm)
|
{
|
atomic_inc(&mm->tlb_flush_pending);
|
/*
|
* The only time this value is relevant is when there are indeed pages
|
* to flush. And we'll only flush pages after changing them, which
|
* requires the PTL.
|
*
|
* So the ordering here is:
|
*
|
* atomic_inc(&mm->tlb_flush_pending);
|
* spin_lock(&ptl);
|
* ...
|
* set_pte_at();
|
* spin_unlock(&ptl);
|
*
|
* spin_lock(&ptl)
|
* mm_tlb_flush_pending();
|
* ....
|
* spin_unlock(&ptl);
|
*
|
* flush_tlb_range();
|
* atomic_dec(&mm->tlb_flush_pending);
|
*
|
* Where the increment if constrained by the PTL unlock, it thus
|
* ensures that the increment is visible if the PTE modification is
|
* visible. After all, if there is no PTE modification, nobody cares
|
* about TLB flushes either.
|
*
|
* This very much relies on users (mm_tlb_flush_pending() and
|
* mm_tlb_flush_nested()) only caring about _specific_ PTEs (and
|
* therefore specific PTLs), because with SPLIT_PTE_PTLOCKS and RCpc
|
* locks (PPC) the unlock of one doesn't order against the lock of
|
* another PTL.
|
*
|
* The decrement is ordered by the flush_tlb_range(), such that
|
* mm_tlb_flush_pending() will not return false unless all flushes have
|
* completed.
|
*/
|
}
|
|
static inline void dec_tlb_flush_pending(struct mm_struct *mm)
|
{
|
/*
|
* See inc_tlb_flush_pending().
|
*
|
* This cannot be smp_mb__before_atomic() because smp_mb() simply does
|
* not order against TLB invalidate completion, which is what we need.
|
*
|
* Therefore we must rely on tlb_flush_*() to guarantee order.
|
*/
|
atomic_dec(&mm->tlb_flush_pending);
|
}
|
|
static inline bool mm_tlb_flush_pending(struct mm_struct *mm)
|
{
|
/*
|
* Must be called after having acquired the PTL; orders against that
|
* PTLs release and therefore ensures that if we observe the modified
|
* PTE we must also observe the increment from inc_tlb_flush_pending().
|
*
|
* That is, it only guarantees to return true if there is a flush
|
* pending for _this_ PTL.
|
*/
|
return atomic_read(&mm->tlb_flush_pending);
|
}
|
|
static inline bool mm_tlb_flush_nested(struct mm_struct *mm)
|
{
|
/*
|
* Similar to mm_tlb_flush_pending(), we must have acquired the PTL
|
* for which there is a TLB flush pending in order to guarantee
|
* we've seen both that PTE modification and the increment.
|
*
|
* (no requirement on actually still holding the PTL, that is irrelevant)
|
*/
|
return atomic_read(&mm->tlb_flush_pending) > 1;
|
}
|
|
struct vm_fault;
|
|
/**
|
* typedef vm_fault_t - Return type for page fault handlers.
|
*
|
* Page fault handlers return a bitmask of %VM_FAULT values.
|
*/
|
typedef __bitwise unsigned int vm_fault_t;
|
|
/**
|
* enum vm_fault_reason - Page fault handlers return a bitmask of
|
* these values to tell the core VM what happened when handling the
|
* fault. Used to decide whether a process gets delivered SIGBUS or
|
* just gets major/minor fault counters bumped up.
|
*
|
* @VM_FAULT_OOM: Out Of Memory
|
* @VM_FAULT_SIGBUS: Bad access
|
* @VM_FAULT_MAJOR: Page read from storage
|
* @VM_FAULT_WRITE: Special case for get_user_pages
|
* @VM_FAULT_HWPOISON: Hit poisoned small page
|
* @VM_FAULT_HWPOISON_LARGE: Hit poisoned large page. Index encoded
|
* in upper bits
|
* @VM_FAULT_SIGSEGV: segmentation fault
|
* @VM_FAULT_NOPAGE: ->fault installed the pte, not return page
|
* @VM_FAULT_LOCKED: ->fault locked the returned page
|
* @VM_FAULT_RETRY: ->fault blocked, must retry
|
* @VM_FAULT_FALLBACK: huge page fault failed, fall back to small
|
* @VM_FAULT_DONE_COW: ->fault has fully handled COW
|
* @VM_FAULT_NEEDDSYNC: ->fault did not modify page tables and needs
|
* fsync() to complete (for synchronous page faults
|
* in DAX)
|
* @VM_FAULT_HINDEX_MASK: mask HINDEX value
|
*
|
*/
|
enum vm_fault_reason {
|
VM_FAULT_OOM = (__force vm_fault_t)0x000001,
|
VM_FAULT_SIGBUS = (__force vm_fault_t)0x000002,
|
VM_FAULT_MAJOR = (__force vm_fault_t)0x000004,
|
VM_FAULT_WRITE = (__force vm_fault_t)0x000008,
|
VM_FAULT_HWPOISON = (__force vm_fault_t)0x000010,
|
VM_FAULT_HWPOISON_LARGE = (__force vm_fault_t)0x000020,
|
VM_FAULT_SIGSEGV = (__force vm_fault_t)0x000040,
|
VM_FAULT_NOPAGE = (__force vm_fault_t)0x000100,
|
VM_FAULT_LOCKED = (__force vm_fault_t)0x000200,
|
VM_FAULT_RETRY = (__force vm_fault_t)0x000400,
|
VM_FAULT_FALLBACK = (__force vm_fault_t)0x000800,
|
VM_FAULT_DONE_COW = (__force vm_fault_t)0x001000,
|
VM_FAULT_NEEDDSYNC = (__force vm_fault_t)0x002000,
|
VM_FAULT_PTNOTSAME = (__force vm_fault_t)0x004000,
|
VM_FAULT_HINDEX_MASK = (__force vm_fault_t)0x0f0000,
|
};
|
|
/* Encode hstate index for a hwpoisoned large page */
|
#define VM_FAULT_SET_HINDEX(x) ((__force vm_fault_t)((x) << 16))
|
#define VM_FAULT_GET_HINDEX(x) (((__force unsigned int)(x) >> 16) & 0xf)
|
|
#define VM_FAULT_ERROR (VM_FAULT_OOM | VM_FAULT_SIGBUS | \
|
VM_FAULT_SIGSEGV | VM_FAULT_HWPOISON | \
|
VM_FAULT_HWPOISON_LARGE | VM_FAULT_FALLBACK)
|
|
#define VM_FAULT_RESULT_TRACE \
|
{ VM_FAULT_OOM, "OOM" }, \
|
{ VM_FAULT_SIGBUS, "SIGBUS" }, \
|
{ VM_FAULT_MAJOR, "MAJOR" }, \
|
{ VM_FAULT_WRITE, "WRITE" }, \
|
{ VM_FAULT_HWPOISON, "HWPOISON" }, \
|
{ VM_FAULT_HWPOISON_LARGE, "HWPOISON_LARGE" }, \
|
{ VM_FAULT_SIGSEGV, "SIGSEGV" }, \
|
{ VM_FAULT_NOPAGE, "NOPAGE" }, \
|
{ VM_FAULT_LOCKED, "LOCKED" }, \
|
{ VM_FAULT_RETRY, "RETRY" }, \
|
{ VM_FAULT_FALLBACK, "FALLBACK" }, \
|
{ VM_FAULT_DONE_COW, "DONE_COW" }, \
|
{ VM_FAULT_NEEDDSYNC, "NEEDDSYNC" }
|
|
struct vm_special_mapping {
|
const char *name; /* The name, e.g. "[vdso]". */
|
|
/*
|
* If .fault is not provided, this points to a
|
* NULL-terminated array of pages that back the special mapping.
|
*
|
* This must not be NULL unless .fault is provided.
|
*/
|
struct page **pages;
|
|
/*
|
* If non-NULL, then this is called to resolve page faults
|
* on the special mapping. If used, .pages is not checked.
|
*/
|
vm_fault_t (*fault)(const struct vm_special_mapping *sm,
|
struct vm_area_struct *vma,
|
struct vm_fault *vmf);
|
|
int (*mremap)(const struct vm_special_mapping *sm,
|
struct vm_area_struct *new_vma);
|
};
|
|
enum tlb_flush_reason {
|
TLB_FLUSH_ON_TASK_SWITCH,
|
TLB_REMOTE_SHOOTDOWN,
|
TLB_LOCAL_SHOOTDOWN,
|
TLB_LOCAL_MM_SHOOTDOWN,
|
TLB_REMOTE_SEND_IPI,
|
NR_TLB_FLUSH_REASONS,
|
};
|
|
/*
|
* A swap entry has to fit into a "unsigned long", as the entry is hidden
|
* in the "index" field of the swapper address space.
|
*/
|
typedef struct {
|
unsigned long val;
|
} swp_entry_t;
|
|
/* Return the name for an anonymous mapping or NULL for a file-backed mapping */
|
static inline const char __user *vma_get_anon_name(struct vm_area_struct *vma)
|
{
|
if (vma->vm_file)
|
return NULL;
|
|
return vma->anon_name;
|
}
|
|
#endif /* _LINUX_MM_TYPES_H */
|
