cregit-Linux how code gets into the kernel

Release 4.12 include/linux/mm_types.h

Directory: include/linux


#include <linux/mm_types_task.h>

#include <linux/auxvec.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/mmu.h>




struct address_space;
struct mem_cgroup;

 * 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 */
	union {
pgoff_t index;		/* Our offset within mapping. */
void *freelist;		/* sl[aou]b first free object */
		/* page_deferred_list().prev    -- second tail page */

	union {
		/* Used for cmpxchg_double in slub */
unsigned long counters;
                 * 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;
		struct {

			union {
                                 * Count of ptes mapped in mms, to show when
                                 * page is mapped & limit reverse map searches.
                                 * Extra information about page type may be
                                 * stored here for pages that are never mapped,
                                 * in which case the value MUST BE <= -2.
                                 * See page-flags.h for more details.
atomic_t _mapcount;

unsigned int active;		/* SLAB */
				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;

         * 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 */
short int pages;
short int pobjects;

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;
unsigned short int compound_dtor;
unsigned short int compound_order;

		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 */

	/* 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.
spinlock_t *ptl;
spinlock_t ptl;
struct kmem_cache *slab_cache;	/* SL[AU]B: Pointer to slab */

struct mem_cgroup *mem_cgroup;

         * 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 */

         * 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;

int _last_cpupid;
 * 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.
	__aligned(2 * sizeof(unsigned long))



struct page_frag_cache {
void * va;
__u16 offset;
__u16 size;
__u32 offset;
	/* 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 */


#define NULL_VM_UFFD_CTX ((struct vm_userfaultfd_ctx) { NULL, })

struct vm_userfaultfd_ctx {
struct userfaultfd_ctx *ctx;

#define NULL_VM_UFFD_CTX ((struct vm_userfaultfd_ctx) {})

struct vm_userfaultfd_ctx {};

 * 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 */
struct mempolicy *vm_policy;	/* NUMA policy for the VMA */
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;

struct kioctx_table;

struct mm_struct {
struct vm_area_struct *mmap;		/* list of VMAs */
struct rb_root mm_rb;
u32 vmacache_seqnum;                   /* per-thread vmacache */
unsigned long (*get_unmapped_area) (struct file *filp,
				unsigned long addr, unsigned long len,
				unsigned long pgoff, unsigned long flags);
unsigned long mmap_base;		/* base of mmap area */
unsigned long mmap_legacy_base;         /* base of mmap area in bottom-up allocations */
	/* Base adresses for compatible mmap() */
unsigned long mmap_compat_base;
unsigned long mmap_compat_legacy_base;
unsigned long task_size;		/* size of task vm space */
unsigned long highest_vm_end;		/* highest vma end address */
pgd_t * pgd;

         * @mm_users: The number of users including userspace.
         * Use mmget()/mmget_not_zero()/mmput() to modify. When this drops
         * to 0 (i.e. when the task exits and there are no other temporary
         * reference holders), we also release a reference on @mm_count
         * (which may then free the &struct mm_struct if @mm_count also
         * drops to 0).
atomic_t mm_users;

         * @mm_count: The number of references to &struct mm_struct
         * (@mm_users count as 1).
         * Use mmgrab()/mmdrop() to modify. When this drops to 0, the
         * &struct mm_struct is freed.
atomic_t mm_count;

atomic_long_t nr_ptes;			/* PTE page table pages */
atomic_long_t nr_pmds;			/* PMD page table pages */
int map_count;				/* number of VMAs */

spinlock_t page_table_lock;		/* Protects page tables and some counters */
struct rw_semaphore mmap_sem;

struct list_head mmlist;		/* List of maybe swapped mm's.  These are globally strung
                                                 * together off init_mm.mmlist, and are protected
                                                 * by mmlist_lock

unsigned long hiwater_rss;	/* High-watermark of RSS usage */
unsigned long hiwater_vm;	/* High-water virtual memory usage */

unsigned long total_vm;		/* Total pages mapped */
unsigned long locked_vm;	/* Pages that have PG_mlocked set */
unsigned long pinned_vm;	/* Refcount permanently increased */
unsigned long data_vm;		/* VM_WRITE & ~VM_SHARED & ~VM_STACK */
unsigned long exec_vm;		/* VM_EXEC & ~VM_WRITE & ~VM_STACK */
unsigned long stack_vm;		/* VM_STACK */
unsigned long def_flags;

unsigned long start_code, end_code, start_data, end_data;

unsigned long start_brk, brk, start_stack;

unsigned long arg_start, arg_end, env_start, env_end;

unsigned long saved_auxv[AT_VECTOR_SIZE]; /* for /proc/PID/auxv */

         * Special counters, in some configurations protected by the
         * page_table_lock, in other configurations by being atomic.
struct mm_rss_stat rss_stat;

struct linux_binfmt *binfmt;

cpumask_var_t cpu_vm_mask_var;

	/* Architecture-specific MM context */
mm_context_t context;

unsigned long flags; /* Must use atomic bitops to access the bits */

struct core_state *core_state; /* coredumping support */
spinlock_t			ioctx_lock;
struct kioctx_table __rcu	*ioctx_table;
         * "owner" points to a task that is regarded as the canonical
         * user/owner of this mm. All of the following must be true in
         * order for it to be changed:
         * current == mm->owner
         * current->mm != mm
         * new_owner->mm == mm
         * new_owner->alloc_lock is held
struct task_struct __rcu *owner;
struct user_namespace *user_ns;

	/* store ref to file /proc/<pid>/exe symlink points to */
struct file __rcu *exe_file;
struct mmu_notifier_mm *mmu_notifier_mm;
pgtable_t pmd_huge_pte; /* protected by page_table_lock */
struct cpumask cpumask_allocation;
         * numa_next_scan is the next time that the PTEs will be marked
         * pte_numa. NUMA hinting faults will gather statistics and migrate
         * pages to new nodes if necessary.
unsigned long numa_next_scan;

	/* Restart point for scanning and setting pte_numa */
unsigned long numa_scan_offset;

	/* numa_scan_seq prevents two threads setting pte_numa */
int numa_scan_seq;
         * An operation with batched TLB flushing is going on. Anything that
         * can move process memory needs to flush the TLB when moving a
         * PROT_NONE or PROT_NUMA mapped page.
bool tlb_flush_pending;
struct uprobes_state uprobes_state;
atomic_long_t hugetlb_usage;
struct work_struct async_put_work;

extern struct mm_struct init_mm;

static inline void mm_init_cpumask(struct mm_struct *mm) { #ifdef CONFIG_CPUMASK_OFFSTACK mm->cpu_vm_mask_var = &mm->cpumask_allocation; #endif cpumask_clear(mm->cpu_vm_mask_var); }


Linus Torvalds2678.79%150.00%
Vladimir Davydov721.21%150.00%

/* Future-safe accessor for struct mm_struct's cpu_vm_mask. */
static inline cpumask_t *mm_cpumask(struct mm_struct *mm) { return mm->cpu_vm_mask_var; }


Motohiro Kosaki1477.78%150.00%
Rusty Russell422.22%150.00%

#if defined(CONFIG_NUMA_BALANCING) || defined(CONFIG_COMPACTION) /* * Memory barriers to keep this state in sync are graciously provided by * the page table locks, outside of which no page table modifications happen. * The barriers below prevent the compiler from re-ordering the instructions * around the memory barriers that are already present in the code. */
static inline bool mm_tlb_flush_pending(struct mm_struct *mm) { barrier(); return mm->tlb_flush_pending; }


Rik Van Riel20100.00%1100.00%

static inline void set_tlb_flush_pending(struct mm_struct *mm) { mm->tlb_flush_pending = true; /* * Guarantee that the tlb_flush_pending store does not leak into the * critical section updating the page tables */ smp_mb__before_spinlock(); }


Rik Van Riel2090.91%150.00%
Mel Gorman29.09%150.00%

/* Clearing is done after a TLB flush, which also provides a barrier. */
static inline void clear_tlb_flush_pending(struct mm_struct *mm) { barrier(); mm->tlb_flush_pending = false; }


Rik Van Riel21100.00%1100.00%

static inline bool mm_tlb_flush_pending(struct mm_struct *mm) { return false; }


Rik Van Riel15100.00%1100.00%

static inline void set_tlb_flush_pending(struct mm_struct *mm) { }


Rik Van Riel11100.00%1100.00%

static inline void clear_tlb_flush_pending(struct mm_struct *mm) { }


Rik Van Riel11100.00%1100.00%

#endif struct vm_fault; 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. */ int (*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; #endif /* _LINUX_MM_TYPES_H */

Overall Contributors

Martin Schwidefsky24018.26%10.92%
Rik Van Riel15111.49%32.75%
Christoph Lameter14110.73%109.17%
Kirill A. Shutemov957.23%1614.68%
Heiko Carstens685.18%21.83%
Andrea Arcangeli554.19%32.75%
David Howells493.73%32.75%
Andrew Lutomirski453.42%21.83%
Alexander Duyck443.35%10.92%
Linus Torvalds403.04%21.83%
Oleg Nesterov382.89%65.50%
Peter Zijlstra342.59%54.59%
Dmitry Safonov322.44%21.83%
Motohiro Kosaki221.67%32.75%
Pravin B Shelar191.45%10.92%
JoonSoo Kim181.37%32.75%
Michel Lespinasse151.14%21.83%
Dave Hansen151.14%21.83%
Vladimir Davydov151.14%32.75%
Olaf Hering130.99%10.92%
Johannes Weiner130.99%10.92%
Mel Gorman120.91%54.59%
Tejun Heo110.84%10.92%
Vegard Nossum100.76%21.83%
Benjamin LaHaise70.53%10.92%
Srikar Dronamraju70.53%10.92%
Michal Hocko70.53%10.92%
Pavel Emelyanov70.53%10.92%
Ingo Molnar70.53%21.83%
Naoya Horiguchi70.53%10.92%
Dan J Williams60.46%10.92%
Alexey Dobriyan60.46%21.83%
Mike Frysinger60.46%10.92%
Matt Helsley60.46%10.92%
Radu Caragea50.38%10.92%
Eric W. Biedermann50.38%10.92%
Konstantin Khlebnikov50.38%32.75%
Hiroshi Shimamoto50.38%10.92%
Rusty Russell50.38%10.92%
Kamezawa Hiroyuki50.38%10.92%
Paul Mundt50.38%10.92%
Richard Kennedy40.30%10.92%
Davidlohr Bueso A30.23%10.92%
Pekka J Enberg20.15%10.92%
Glauber de Oliveira Costa20.15%10.92%
Akinobu Mita20.15%10.92%
Jens Axboe20.15%10.92%
Balbir Singh20.15%10.92%
Arnd Bergmann10.08%10.92%
Directory: include/linux
Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.
Created with cregit.