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#ifndef _LINUX_MM_TYPES_H
#define _LINUX_MM_TYPES_H
#include <linux/auxvec.h>
#include <linux/types.h>
#include <linux/threads.h>
#include <linux/list.h>
#include <linux/spinlock.h>
#include <linux/rbtree.h>
#include <linux/rwsem.h>
#include <linux/completion.h>
#include <linux/cpumask.h>
#include <linux/uprobes.h>
#include <linux/page-flags-layout.h>
#include <linux/workqueue.h>
#include <asm/page.h>
#include <asm/mmu.h>
#ifndef AT_VECTOR_SIZE_ARCH
#define AT_VECTOR_SIZE_ARCH 0
#endif
#define AT_VECTOR_SIZE (2*(AT_VECTOR_SIZE_ARCH + AT_VECTOR_SIZE_BASE + 1))
struct address_space;
struct mem_cgroup;
#define USE_SPLIT_PTE_PTLOCKS (NR_CPUS >= CONFIG_SPLIT_PTLOCK_CPUS)
#define USE_SPLIT_PMD_PTLOCKS (USE_SPLIT_PTE_PTLOCKS && \
IS_ENABLED(CONFIG_ARCH_ENABLE_SPLIT_PMD_PTLOCK))
#define ALLOC_SPLIT_PTLOCKS (SPINLOCK_SIZE > BITS_PER_LONG/8)
/*
* Each physical page in the system has a struct page associated with
* it to keep track of whatever it is we are using the page for at the
* moment. Note that we have no way to track which tasks are using
* a page, though if it is a pagecache page, rmap structures can tell us
* who is mapping it.
*
* The objects in struct page are organized in double word blocks in
* order to allows us to use atomic double word operations on portions
* of struct page. That is currently only used by slub but the arrangement
* allows the use of atomic double word operations on the flags/mapping
* and lru list pointers also.
*/
struct page {
/* First double word block */
unsigned long flags; /* Atomic flags, some possibly
* updated asynchronously */
union {
struct address_space *mapping; /* If low bit clear, points to
* inode address_space, or NULL.
* If page mapped as anonymous
* memory, low bit is set, and
* it points to anon_vma object:
* see PAGE_MAPPING_ANON below.
*/
void *s_mem; /* slab first object */
atomic_t compound_mapcount; /* first tail page */
/* page_deferred_list().next -- second tail page */
};
/* Second double word */
struct {
union {
pgoff_t index; /* Our offset within mapping. */
void *freelist; /* sl[aou]b first free object */
/* page_deferred_list().prev -- second tail page */
};
union {
#if defined(CONFIG_HAVE_CMPXCHG_DOUBLE) && \
defined(CONFIG_HAVE_ALIGNED_STRUCT_PAGE)
/* Used for cmpxchg_double in slub */
unsigned long counters;
#else
/*
* Keep _refcount separate from slub cmpxchg_double
* data. As the rest of the double word is protected by
* slab_lock but _refcount is not.
*/
unsigned counters;
#endif
struct {
union {
/*
* Count of ptes mapped in mms, to show
* when page is mapped & limit reverse
* map searches.
*/
atomic_t _mapcount;
struct { /* SLUB */
unsigned inuse:16;
unsigned objects:15;
unsigned frozen:1;
};
int units; /* SLOB */
};
/*
* Usage count, *USE WRAPPER FUNCTION*
* when manual accounting. See page_ref.h
*/
atomic_t _refcount;
};
unsigned int active; /* SLAB */
};
};
/*
* Third double word block
*
* WARNING: bit 0 of the first word encode PageTail(). That means
* the rest users of the storage space MUST NOT use the bit to
* avoid collision and false-positive PageTail().
*/
union {
struct list_head lru; /* Pageout list, eg. active_list
* protected by zone->lru_lock !
* Can be used as a generic list
* by the page owner.
*/
struct dev_pagemap *pgmap; /* ZONE_DEVICE pages are never on an
* lru or handled by a slab
* allocator, this points to the
* hosting device page map.
*/
struct { /* slub per cpu partial pages */
struct page *next; /* Next partial slab */
#ifdef CONFIG_64BIT
int pages; /* Nr of partial slabs left */
int pobjects; /* Approximate # of objects */
#else
short int pages;
short int pobjects;
#endif
};
struct rcu_head rcu_head; /* Used by SLAB
* when destroying via RCU
*/
/* Tail pages of compound page */
struct {
unsigned long compound_head; /* If bit zero is set */
/* First tail page only */
#ifdef CONFIG_64BIT
/*
* On 64 bit system we have enough space in struct page
* to encode compound_dtor and compound_order with
* unsigned int. It can help compiler generate better or
* smaller code on some archtectures.
*/
unsigned int compound_dtor;
unsigned int compound_order;
#else
unsigned short int compound_dtor;
unsigned short int compound_order;
#endif
};
#if defined(CONFIG_TRANSPARENT_HUGEPAGE) && USE_SPLIT_PMD_PTLOCKS
struct {
unsigned long __pad; /* do not overlay pmd_huge_pte
* with compound_head to avoid
* possible bit 0 collision.
*/
pgtable_t pmd_huge_pte; /* protected by page->ptl */
};
#endif
};
/* Remainder is not double word aligned */
union {
unsigned long private; /* Mapping-private opaque data:
* usually used for buffer_heads
* if PagePrivate set; used for
* swp_entry_t if PageSwapCache;
* indicates order in the buddy
* system if PG_buddy is set.
*/
#if USE_SPLIT_PTE_PTLOCKS
#if ALLOC_SPLIT_PTLOCKS
spinlock_t *ptl;
#else
spinlock_t ptl;
#endif
#endif
struct kmem_cache *slab_cache; /* SL[AU]B: Pointer to slab */
};
#ifdef CONFIG_MEMCG
struct mem_cgroup *mem_cgroup;
#endif
/*
* On machines where all RAM is mapped into kernel address space,
* we can simply calculate the virtual address. On machines with
* highmem some memory is mapped into kernel virtual memory
* dynamically, so we need a place to store that address.
* Note that this field could be 16 bits on x86 ... ;)
*
* Architectures with slow multiplication can define
* WANT_PAGE_VIRTUAL in asm/page.h
*/
#if defined(WANT_PAGE_VIRTUAL)
void *virtual; /* Kernel virtual address (NULL if
not kmapped, ie. highmem) */
#endif /* WANT_PAGE_VIRTUAL */
#ifdef CONFIG_KMEMCHECK
/*
* kmemcheck wants to track the status of each byte in a page; this
* is a pointer to such a status block. NULL if not tracked.
*/
void *shadow;
#endif
#ifdef LAST_CPUPID_NOT_IN_PAGE_FLAGS
int _last_cpupid;
#endif
}
/*
* The struct page can be forced to be double word aligned so that atomic ops
* on double words work. The SLUB allocator can make use of such a feature.
*/
#ifdef CONFIG_HAVE_ALIGNED_STRUCT_PAGE
__aligned(2 * sizeof(unsigned long))
#endif
;
struct page_frag {
struct page *page;
#if (BITS_PER_LONG > 32) || (PAGE_SIZE >= 65536)
__u32 offset;
__u32 size;
#else
__u16 offset;
__u16 size;
#endif
};
#define PAGE_FRAG_CACHE_MAX_SIZE __ALIGN_MASK(32768, ~PAGE_MASK)
#define PAGE_FRAG_CACHE_MAX_ORDER get_order(PAGE_FRAG_CACHE_MAX_SIZE)
struct page_frag_cache {
void * va;
#if (PAGE_SIZE < PAGE_FRAG_CACHE_MAX_SIZE)
__u16 offset;
__u16 size;
#else
__u32 offset;
#endif
/* we maintain a pagecount bias, so that we dont dirty cache line
* containing page->_refcount every time we allocate a fragment.
*/
unsigned int pagecnt_bias;
bool pfmemalloc;
};
typedef unsigned long vm_flags_t;
/*
* A region containing a mapping of a non-memory backed file under NOMMU
* conditions. These are held in a global tree and are pinned by the VMAs that
* map parts of them.
*/
struct vm_region {
struct rb_node vm_rb; /* link in global region tree */
vm_flags_t vm_flags; /* VMA vm_flags */
unsigned long vm_start; /* start address of region */
unsigned long vm_end; /* region initialised to here */
unsigned long vm_top; /* region allocated to here */
unsigned long vm_pgoff; /* the offset in vm_file corresponding to vm_start */
struct file *vm_file; /* the backing file or NULL */
int vm_usage; /* region usage count (access under nommu_region_sem) */
bool vm_icache_flushed : 1; /* true if the icache has been flushed for
* this region */
};
#ifdef CONFIG_USERFAULTFD
#define NULL_VM_UFFD_CTX ((struct vm_userfaultfd_ctx) { NULL, })
struct vm_userfaultfd_ctx {
struct userfaultfd_ctx *ctx;
};
#else /* CONFIG_USERFAULTFD */
#define NULL_VM_UFFD_CTX ((struct vm_userfaultfd_ctx) {})
struct vm_userfaultfd_ctx {};
#endif /* CONFIG_USERFAULTFD */
/*
* This struct defines a memory VMM memory area. There is one of these
* per VM-area/task. A VM area is any part of the process virtual memory
* space that has a special rule for the page-fault handlers (ie a shared
* library, the executable area etc).
*/
struct vm_area_struct {
/* The first cache line has the info for VMA tree walking. */
unsigned long vm_start; /* Our start address within vm_mm. */
unsigned long vm_end; /* The first byte after our end address
within vm_mm. */
/* linked list of VM areas per task, sorted by address */
struct vm_area_struct *vm_next, *vm_prev;
struct rb_node vm_rb;
/*
* Largest free memory gap in bytes to the left of this VMA.
* Either between this VMA and vma->vm_prev, or between one of the
* VMAs below us in the VMA rbtree and its ->vm_prev. This helps
* get_unmapped_area find a free area of the right size.
*/
unsigned long rb_subtree_gap;
/* Second cache line starts here. */
struct mm_struct *vm_mm; /* The address space we belong to. */
pgprot_t vm_page_prot; /* Access permissions of this VMA. */
unsigned long vm_flags; /* Flags, see mm.h. */
/*
* For areas with an address space and backing store,
* linkage into the address_space->i_mmap interval tree.
*/
struct {
struct rb_node rb;
unsigned long rb_subtree_last;
} shared;
/*
* A file's MAP_PRIVATE vma can be in both i_mmap tree and anon_vma
* list, after a COW of one of the file pages. A MAP_SHARED vma
* can only be in the i_mmap tree. An anonymous MAP_PRIVATE, stack
* or brk vma (with NULL file) can only be in an anon_vma list.
*/
struct list_head anon_vma_chain; /* Serialized by mmap_sem &
* page_table_lock */
struct anon_vma *anon_vma; /* Serialized by page_table_lock */
/* Function pointers to deal with this struct. */
const struct vm_operations_struct *vm_ops;
/* Information about our backing store: */
unsigned long vm_pgoff; /* Offset (within vm_file) in PAGE_SIZE
units */
struct file * vm_file; /* File we map to (can be NULL). */
void * vm_private_data; /* was vm_pte (shared mem) */
#ifndef CONFIG_MMU
struct vm_region *vm_region; /* NOMMU mapping region */
#endif
#ifdef CONFIG_NUMA
struct mempolicy *vm_policy; /* NUMA policy for the VMA */
#endif
struct vm_userfaultfd_ctx vm_userfaultfd_ctx;
};
struct core_thread {
struct task_struct *task;
struct core_thread *next;
};
struct core_state {
atomic_t nr_threads;
struct core_thread dumper;
struct completion startup;
};
enum {
MM_FILEPAGES, /* Resident file mapping pages */
MM_ANONPAGES,
|