[mirror_ubuntu-zesty-kernel.git] / include / linux / mm_types.h

#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/prio_tree.h>
#include <linux/rbtree.h>
#include <linux/rwsem.h>
#include <linux/completion.h>
#include <linux/cpumask.h>
#include <linux/page-debug-flags.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;

#define USE_SPLIT_PTLOCKS	(NR_CPUS >= CONFIG_SPLIT_PTLOCK_CPUS)

#if USE_SPLIT_PTLOCKS
typedef atomic_long_t mm_counter_t;
#else  /* !USE_SPLIT_PTLOCKS */
typedef unsigned long mm_counter_t;
#endif /* !USE_SPLIT_PTLOCKS */

/*
 * 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.
 */
struct page {
	unsigned long flags;		/* Atomic flags, some possibly
					 * updated asynchronously */
	atomic_t _count;		/* Usage count, see below. */
	union {
		atomic_t _mapcount;	/* Count of ptes mapped in mms,
					 * to show when page is mapped
					 * & limit reverse map searches.
					 */
		struct {		/* SLUB */
			u16 inuse;
			u16 objects;
		};
	};
	union {
	    struct {
		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.
						 */
		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.
						 */
	    };
#if USE_SPLIT_PTLOCKS
	    spinlock_t ptl;
#endif
	    struct kmem_cache *slab;	/* SLUB: Pointer to slab */
	    struct page *first_page;	/* Compound tail pages */
	};
	union {
		pgoff_t index;		/* Our offset within mapping. */
		void *freelist;		/* SLUB: freelist req. slab lock */
	};
	struct list_head lru;		/* Pageout list, eg. active_list
					 * protected by zone->lru_lock !
					 */
	/*
	 * 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_WANT_PAGE_DEBUG_FLAGS
	unsigned long debug_flags;	/* Use atomic bitops on this */
#endif

#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
};

/*
 * 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 */
	unsigned long	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 */
};

/*
 * 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 {
	struct mm_struct * vm_mm;	/* The address space we belong to. */
	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;

	pgprot_t vm_page_prot;		/* Access permissions of this VMA. */
	unsigned long vm_flags;		/* Flags, see mm.h. */

	struct rb_node vm_rb;

	/*
	 * For areas with an address space and backing store,
	 * linkage into the address_space->i_mmap prio tree, or
	 * linkage to the list of like vmas hanging off its node, or
	 * linkage of vma in the address_space->i_mmap_nonlinear list.
	 */
	union {
		struct {
			struct list_head list;
			void *parent;	/* aligns with prio_tree_node parent */
			struct vm_area_struct *head;
		} vm_set;

		struct raw_prio_tree_node prio_tree_node;
	} 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_node;	/* Serialized by anon_vma->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, *not* PAGE_CACHE_SIZE */
	struct file * vm_file;		/* File we map to (can be NULL). */
	void * vm_private_data;		/* was vm_pte (shared mem) */
	unsigned long vm_truncate_count;/* truncate_count or restart_addr */

#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 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 mm_struct {
	struct vm_area_struct * mmap;		/* list of VMAs */
	struct rb_root mm_rb;
	struct vm_area_struct * mmap_cache;	/* last find_vma result */
#ifdef CONFIG_MMU
	unsigned long (*get_unmapped_area) (struct file *filp,
				unsigned long addr, unsigned long len,
				unsigned long pgoff, unsigned long flags);
	void (*unmap_area) (struct mm_struct *mm, unsigned long addr);
#endif
	unsigned long mmap_base;		/* base of mmap area */
	unsigned long task_size;		/* size of task vm space */
	unsigned long cached_hole_size; 	/* if non-zero, the largest hole below free_area_cache */
	unsigned long free_area_cache;		/* first hole of size cached_hole_size or larger */
	pgd_t * pgd;
	atomic_t mm_users;			/* How many users with user space? */
	atomic_t mm_count;			/* How many references to "struct mm_struct" (users count as 1) */
	int map_count;				/* number of VMAs */
	struct rw_semaphore mmap_sem;
	spinlock_t page_table_lock;		/* Protects page tables and some counters */

	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
						 */

	/* Special counters, in some configurations protected by the
	 * page_table_lock, in other configurations by being atomic.
	 */
	mm_counter_t _file_rss;
	mm_counter_t _anon_rss;

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

	unsigned long total_vm, locked_vm, shared_vm, exec_vm;
	unsigned long stack_vm, reserved_vm, def_flags, nr_ptes;
	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 */

	struct linux_binfmt *binfmt;

	cpumask_t cpu_vm_mask;

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

	/* Swap token stuff */
	/*
	 * Last value of global fault stamp as seen by this process.
	 * In other words, this value gives an indication of how long
	 * it has been since this task got the token.
	 * Look at mm/thrash.c
	 */
	unsigned int faultstamp;
	unsigned int token_priority;
	unsigned int last_interval;

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

	struct core_state *core_state; /* coredumping support */
#ifdef CONFIG_AIO
	spinlock_t		ioctx_lock;
	struct hlist_head	ioctx_list;
#endif
#ifdef CONFIG_MM_OWNER
	/*
	 * "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 *owner;
#endif

#ifdef CONFIG_PROC_FS
	/* store ref to file /proc/<pid>/exe symlink points to */
	struct file *exe_file;
	unsigned long num_exe_file_vmas;
#endif
#ifdef CONFIG_MMU_NOTIFIER
	struct mmu_notifier_mm *mmu_notifier_mm;
#endif
};

/* Future-safe accessor for struct mm_struct's cpu_vm_mask. */
#define mm_cpumask(mm) (&(mm)->cpu_vm_mask)

#endif /* _LINUX_MM_TYPES_H */
Commit	Line	Data
5b99cd0e HC	1	#ifndef _LINUX_MM_TYPES_H
	2	#define _LINUX_MM_TYPES_H
	3
4f9a58d7	4	#include <linux/auxvec.h>
5b99cd0e HC	5	#include <linux/types.h>
	6	#include <linux/threads.h>
	7	#include <linux/list.h>
	8	#include <linux/spinlock.h>
c92ff1bd MS	9	#include <linux/prio_tree.h>
	10	#include <linux/rbtree.h>
	11	#include <linux/rwsem.h>
	12	#include <linux/completion.h>
cddb8a5c	13	#include <linux/cpumask.h>
6a11f75b	14	#include <linux/page-debug-flags.h>
c92ff1bd MS	15	#include <asm/page.h>
c92ff1bd MS	16	#include <asm/mmu.h>
5b99cd0e	17
4f9a58d7 OH	18	#ifndef AT_VECTOR_SIZE_ARCH
	19	#define AT_VECTOR_SIZE_ARCH 0
	20	#endif
	21	#define AT_VECTOR_SIZE (2*(AT_VECTOR_SIZE_ARCH + AT_VECTOR_SIZE_BASE + 1))
	22
5b99cd0e HC	23	struct address_space;
5b99cd0e HC	24
f7d0b926 JF	25	#define USE_SPLIT_PTLOCKS (NR_CPUS >= CONFIG_SPLIT_PTLOCK_CPUS)
	26
	27	#if USE_SPLIT_PTLOCKS
c92ff1bd	28	typedef atomic_long_t mm_counter_t;
f7d0b926	29	#else /* !USE_SPLIT_PTLOCKS */
c92ff1bd	30	typedef unsigned long mm_counter_t;
f7d0b926	31	#endif /* !USE_SPLIT_PTLOCKS */
c92ff1bd	32
5b99cd0e HC	33	/*
	34	* Each physical page in the system has a struct page associated with
	35	* it to keep track of whatever it is we are using the page for at the
	36	* moment. Note that we have no way to track which tasks are using
	37	* a page, though if it is a pagecache page, rmap structures can tell us
	38	* who is mapping it.
	39	*/
	40	struct page {
	41	unsigned long flags; /* Atomic flags, some possibly
	42	* updated asynchronously */
	43	atomic_t _count; /* Usage count, see below. */
81819f0f CL	44	union {
81819f0f CL	45	atomic_t _mapcount; /* Count of ptes mapped in mms,
5b99cd0e HC	46	* to show when page is mapped
	47	* & limit reverse map searches.
	48	*/
39b26464 CL	49	struct { /* SLUB */
	50	u16 inuse;
	51	u16 objects;
	52	};
81819f0f	53	};
5b99cd0e HC	54	union {
	55	struct {
	56	unsigned long private; /* Mapping-private opaque data:
	57	* usually used for buffer_heads
	58	* if PagePrivate set; used for
	59	* swp_entry_t if PageSwapCache;
	60	* indicates order in the buddy
	61	* system if PG_buddy is set.
	62	*/
	63	struct address_space mapping; / If low bit clear, points to
	64	* inode address_space, or NULL.
	65	* If page mapped as anonymous
	66	* memory, low bit is set, and
	67	* it points to anon_vma object:
	68	* see PAGE_MAPPING_ANON below.
	69	*/
	70	};
f7d0b926	71	#if USE_SPLIT_PTLOCKS
5b99cd0e HC	72	spinlock_t ptl;
5b99cd0e HC	73	#endif
a973e9dd	74	struct kmem_cache slab; / SLUB: Pointer to slab */
8e65d24c	75	struct page first_page; / Compound tail pages */
81819f0f CL	76	};
	77	union {
	78	pgoff_t index; /* Our offset within mapping. */
894b8788	79	void freelist; / SLUB: freelist req. slab lock */
5b99cd0e	80	};
5b99cd0e HC	81	struct list_head lru; /* Pageout list, eg. active_list
	82	* protected by zone->lru_lock !
	83	*/
	84	/*
	85	* On machines where all RAM is mapped into kernel address space,
	86	* we can simply calculate the virtual address. On machines with
	87	* highmem some memory is mapped into kernel virtual memory
	88	* dynamically, so we need a place to store that address.
	89	* Note that this field could be 16 bits on x86 ... ;)
	90	*
	91	* Architectures with slow multiplication can define
	92	* WANT_PAGE_VIRTUAL in asm/page.h
	93	*/
	94	#if defined(WANT_PAGE_VIRTUAL)
	95	void virtual; / Kernel virtual address (NULL if
	96	not kmapped, ie. highmem) */
	97	#endif /* WANT_PAGE_VIRTUAL */
ee3b4290 AM	98	#ifdef CONFIG_WANT_PAGE_DEBUG_FLAGS
	99	unsigned long debug_flags; /* Use atomic bitops on this */
	100	#endif
dfec072e VN	101
	102	#ifdef CONFIG_KMEMCHECK
	103	/*
	104	* kmemcheck wants to track the status of each byte in a page; this
	105	* is a pointer to such a status block. NULL if not tracked.
	106	*/
	107	void *shadow;
	108	#endif
5b99cd0e HC	109	};
5b99cd0e HC	110
8feae131 DH	111	/*
	112	* A region containing a mapping of a non-memory backed file under NOMMU
	113	* conditions. These are held in a global tree and are pinned by the VMAs that
	114	* map parts of them.
	115	*/
	116	struct vm_region {
	117	struct rb_node vm_rb; /* link in global region tree */
	118	unsigned long vm_flags; /* VMA vm_flags */
	119	unsigned long vm_start; /* start address of region */
	120	unsigned long vm_end; /* region initialised to here */
dd8632a1	121	unsigned long vm_top; /* region allocated to here */
8feae131 DH	122	unsigned long vm_pgoff; /* the offset in vm_file corresponding to vm_start */
	123	struct file vm_file; / the backing file or NULL */
	124
1e2ae599	125	int vm_usage; /* region usage count (access under nommu_region_sem) */
cfe79c00 MF	126	bool vm_icache_flushed : 1; /* true if the icache has been flushed for
cfe79c00 MF	127	* this region */
8feae131 DH	128	};
8feae131 DH	129
c92ff1bd MS	130	/*
	131	* This struct defines a memory VMM memory area. There is one of these
	132	* per VM-area/task. A VM area is any part of the process virtual memory
	133	* space that has a special rule for the page-fault handlers (ie a shared
	134	* library, the executable area etc).
	135	*/
	136	struct vm_area_struct {
	137	struct mm_struct * vm_mm; /* The address space we belong to. */
	138	unsigned long vm_start; /* Our start address within vm_mm. */
	139	unsigned long vm_end; /* The first byte after our end address
	140	within vm_mm. */
	141
	142	/* linked list of VM areas per task, sorted by address */
	143	struct vm_area_struct *vm_next;
	144
	145	pgprot_t vm_page_prot; /* Access permissions of this VMA. */
605d9288	146	unsigned long vm_flags; /* Flags, see mm.h. */
c92ff1bd MS	147
	148	struct rb_node vm_rb;
	149
	150	/*
	151	* For areas with an address space and backing store,
	152	* linkage into the address_space->i_mmap prio tree, or
	153	* linkage to the list of like vmas hanging off its node, or
	154	* linkage of vma in the address_space->i_mmap_nonlinear list.
	155	*/
	156	union {
	157	struct {
	158	struct list_head list;
	159	void parent; / aligns with prio_tree_node parent */
	160	struct vm_area_struct *head;
	161	} vm_set;
	162
	163	struct raw_prio_tree_node prio_tree_node;
	164	} shared;
	165
	166	/*
	167	* A file's MAP_PRIVATE vma can be in both i_mmap tree and anon_vma
	168	* list, after a COW of one of the file pages. A MAP_SHARED vma
	169	* can only be in the i_mmap tree. An anonymous MAP_PRIVATE, stack
	170	* or brk vma (with NULL file) can only be in an anon_vma list.
	171	*/
	172	struct list_head anon_vma_node; /* Serialized by anon_vma->lock */
	173	struct anon_vma anon_vma; / Serialized by page_table_lock */
	174
	175	/* Function pointers to deal with this struct. */
f0f37e2f	176	const struct vm_operations_struct *vm_ops;
c92ff1bd MS	177
	178	/* Information about our backing store: */
	179	unsigned long vm_pgoff; /* Offset (within vm_file) in PAGE_SIZE
	180	units, not PAGE_CACHE_SIZE */
	181	struct file * vm_file; /* File we map to (can be NULL). */
	182	void * vm_private_data; /* was vm_pte (shared mem) */
	183	unsigned long vm_truncate_count;/* truncate_count or restart_addr */
	184
	185	#ifndef CONFIG_MMU
8feae131	186	struct vm_region vm_region; / NOMMU mapping region */
c92ff1bd MS	187	#endif
	188	#ifdef CONFIG_NUMA
	189	struct mempolicy vm_policy; / NUMA policy for the VMA */
	190	#endif
	191	};
	192
b564daf8 ON	193	struct core_thread {
	194	struct task_struct *task;
	195	struct core_thread *next;
	196	};
	197
32ecb1f2	198	struct core_state {
c5f1cc8c	199	atomic_t nr_threads;
b564daf8	200	struct core_thread dumper;
32ecb1f2 ON	201	struct completion startup;
	202	};
	203
c92ff1bd MS	204	struct mm_struct {
	205	struct vm_area_struct * mmap; /* list of VMAs */
	206	struct rb_root mm_rb;
	207	struct vm_area_struct * mmap_cache; /* last find_vma result */
efc1a3b1	208	#ifdef CONFIG_MMU
c92ff1bd MS	209	unsigned long (get_unmapped_area) (struct file filp,
	210	unsigned long addr, unsigned long len,
	211	unsigned long pgoff, unsigned long flags);
	212	void (unmap_area) (struct mm_struct mm, unsigned long addr);
efc1a3b1	213	#endif
c92ff1bd MS	214	unsigned long mmap_base; /* base of mmap area */
	215	unsigned long task_size; /* size of task vm space */
	216	unsigned long cached_hole_size; /* if non-zero, the largest hole below free_area_cache */
	217	unsigned long free_area_cache; /* first hole of size cached_hole_size or larger */
	218	pgd_t * pgd;
	219	atomic_t mm_users; /* How many users with user space? */
	220	atomic_t mm_count; /* How many references to "struct mm_struct" (users count as 1) */
	221	int map_count; /* number of VMAs */
	222	struct rw_semaphore mmap_sem;
	223	spinlock_t page_table_lock; /* Protects page tables and some counters */
	224
	225	struct list_head mmlist; /* List of maybe swapped mm's. These are globally strung
	226	* together off init_mm.mmlist, and are protected
	227	* by mmlist_lock
	228	*/
	229
	230	/* Special counters, in some configurations protected by the
	231	* page_table_lock, in other configurations by being atomic.
	232	*/
	233	mm_counter_t _file_rss;
	234	mm_counter_t _anon_rss;
	235
	236	unsigned long hiwater_rss; /* High-watermark of RSS usage */
	237	unsigned long hiwater_vm; /* High-water virtual memory usage */
	238
	239	unsigned long total_vm, locked_vm, shared_vm, exec_vm;
	240	unsigned long stack_vm, reserved_vm, def_flags, nr_ptes;
	241	unsigned long start_code, end_code, start_data, end_data;
	242	unsigned long start_brk, brk, start_stack;
	243	unsigned long arg_start, arg_end, env_start, env_end;
	244
	245	unsigned long saved_auxv[AT_VECTOR_SIZE]; /* for /proc/PID/auxv */
	246
801460d0 HS	247	struct linux_binfmt *binfmt;
801460d0 HS	248
c92ff1bd MS	249	cpumask_t cpu_vm_mask;
	250
	251	/* Architecture-specific MM context */
	252	mm_context_t context;
	253
	254	/* Swap token stuff */
	255	/*
	256	* Last value of global fault stamp as seen by this process.
	257	* In other words, this value gives an indication of how long
	258	* it has been since this task got the token.
	259	* Look at mm/thrash.c
	260	*/
	261	unsigned int faultstamp;
	262	unsigned int token_priority;
	263	unsigned int last_interval;
	264
	265	unsigned long flags; /* Must use atomic bitops to access the bits */
	266
a94e2d40	267	struct core_state core_state; / coredumping support */
858f0993	268	#ifdef CONFIG_AIO
abf137dd JA	269	spinlock_t ioctx_lock;
abf137dd JA	270	struct hlist_head ioctx_list;
858f0993	271	#endif
cf475ad2	272	#ifdef CONFIG_MM_OWNER
4cd1a8fc KM	273	/*
	274	* "owner" points to a task that is regarded as the canonical
	275	* user/owner of this mm. All of the following must be true in
	276	* order for it to be changed:
	277	*
	278	* current == mm->owner
	279	* current->mm != mm
	280	* new_owner->mm == mm
	281	* new_owner->alloc_lock is held
	282	*/
	283	struct task_struct *owner;
78fb7466	284	#endif
925d1c40 MH	285
	286	#ifdef CONFIG_PROC_FS
	287	/* store ref to file /proc/<pid>/exe symlink points to */
	288	struct file *exe_file;
	289	unsigned long num_exe_file_vmas;
	290	#endif
cddb8a5c AA	291	#ifdef CONFIG_MMU_NOTIFIER
	292	struct mmu_notifier_mm *mmu_notifier_mm;
	293	#endif
c92ff1bd MS	294	};
c92ff1bd MS	295
45e575ab RR	296	/* Future-safe accessor for struct mm_struct's cpu_vm_mask. */
	297	#define mm_cpumask(mm) (&(mm)->cpu_vm_mask)
	298
5b99cd0e	299	#endif /* _LINUX_MM_TYPES_H */