1 #ifndef _LINUX_MM_TYPES_H
2 #define _LINUX_MM_TYPES_H
4 #include <linux/auxvec.h>
5 #include <linux/types.h>
6 #include <linux/threads.h>
7 #include <linux/list.h>
8 #include <linux/spinlock.h>
9 #include <linux/prio_tree.h>
10 #include <linux/rbtree.h>
11 #include <linux/rwsem.h>
12 #include <linux/completion.h>
13 #include <linux/cpumask.h>
17 #ifndef AT_VECTOR_SIZE_ARCH
18 #define AT_VECTOR_SIZE_ARCH 0
20 #define AT_VECTOR_SIZE (2*(AT_VECTOR_SIZE_ARCH + AT_VECTOR_SIZE_BASE + 1))
24 #define USE_SPLIT_PTLOCKS (NR_CPUS >= CONFIG_SPLIT_PTLOCK_CPUS)
27 typedef atomic_long_t mm_counter_t
;
28 #else /* !USE_SPLIT_PTLOCKS */
29 typedef unsigned long mm_counter_t
;
30 #endif /* !USE_SPLIT_PTLOCKS */
33 * Each physical page in the system has a struct page associated with
34 * it to keep track of whatever it is we are using the page for at the
35 * moment. Note that we have no way to track which tasks are using
36 * a page, though if it is a pagecache page, rmap structures can tell us
40 unsigned long flags
; /* Atomic flags, some possibly
41 * updated asynchronously */
42 atomic_t _count
; /* Usage count, see below. */
44 atomic_t _mapcount
; /* Count of ptes mapped in mms,
45 * to show when page is mapped
46 * & limit reverse map searches.
55 unsigned long private; /* Mapping-private opaque data:
56 * usually used for buffer_heads
57 * if PagePrivate set; used for
58 * swp_entry_t if PageSwapCache;
59 * indicates order in the buddy
60 * system if PG_buddy is set.
62 struct address_space
*mapping
; /* If low bit clear, points to
63 * inode address_space, or NULL.
64 * If page mapped as anonymous
65 * memory, low bit is set, and
66 * it points to anon_vma object:
67 * see PAGE_MAPPING_ANON below.
73 struct kmem_cache
*slab
; /* SLUB: Pointer to slab */
74 struct page
*first_page
; /* Compound tail pages */
77 pgoff_t index
; /* Our offset within mapping. */
78 void *freelist
; /* SLUB: freelist req. slab lock */
80 struct list_head lru
; /* Pageout list, eg. active_list
81 * protected by zone->lru_lock !
84 * On machines where all RAM is mapped into kernel address space,
85 * we can simply calculate the virtual address. On machines with
86 * highmem some memory is mapped into kernel virtual memory
87 * dynamically, so we need a place to store that address.
88 * Note that this field could be 16 bits on x86 ... ;)
90 * Architectures with slow multiplication can define
91 * WANT_PAGE_VIRTUAL in asm/page.h
93 #if defined(WANT_PAGE_VIRTUAL)
94 void *virtual; /* Kernel virtual address (NULL if
95 not kmapped, ie. highmem) */
96 #endif /* WANT_PAGE_VIRTUAL */
100 * A region containing a mapping of a non-memory backed file under NOMMU
101 * conditions. These are held in a global tree and are pinned by the VMAs that
105 struct rb_node vm_rb
; /* link in global region tree */
106 unsigned long vm_flags
; /* VMA vm_flags */
107 unsigned long vm_start
; /* start address of region */
108 unsigned long vm_end
; /* region initialised to here */
109 unsigned long vm_top
; /* region allocated to here */
110 unsigned long vm_pgoff
; /* the offset in vm_file corresponding to vm_start */
111 struct file
*vm_file
; /* the backing file or NULL */
113 atomic_t vm_usage
; /* region usage count */
117 * This struct defines a memory VMM memory area. There is one of these
118 * per VM-area/task. A VM area is any part of the process virtual memory
119 * space that has a special rule for the page-fault handlers (ie a shared
120 * library, the executable area etc).
122 struct vm_area_struct
{
123 struct mm_struct
* vm_mm
; /* The address space we belong to. */
124 unsigned long vm_start
; /* Our start address within vm_mm. */
125 unsigned long vm_end
; /* The first byte after our end address
128 /* linked list of VM areas per task, sorted by address */
129 struct vm_area_struct
*vm_next
;
131 pgprot_t vm_page_prot
; /* Access permissions of this VMA. */
132 unsigned long vm_flags
; /* Flags, see mm.h. */
134 struct rb_node vm_rb
;
137 * For areas with an address space and backing store,
138 * linkage into the address_space->i_mmap prio tree, or
139 * linkage to the list of like vmas hanging off its node, or
140 * linkage of vma in the address_space->i_mmap_nonlinear list.
144 struct list_head list
;
145 void *parent
; /* aligns with prio_tree_node parent */
146 struct vm_area_struct
*head
;
149 struct raw_prio_tree_node prio_tree_node
;
153 * A file's MAP_PRIVATE vma can be in both i_mmap tree and anon_vma
154 * list, after a COW of one of the file pages. A MAP_SHARED vma
155 * can only be in the i_mmap tree. An anonymous MAP_PRIVATE, stack
156 * or brk vma (with NULL file) can only be in an anon_vma list.
158 struct list_head anon_vma_node
; /* Serialized by anon_vma->lock */
159 struct anon_vma
*anon_vma
; /* Serialized by page_table_lock */
161 /* Function pointers to deal with this struct. */
162 struct vm_operations_struct
* vm_ops
;
164 /* Information about our backing store: */
165 unsigned long vm_pgoff
; /* Offset (within vm_file) in PAGE_SIZE
166 units, *not* PAGE_CACHE_SIZE */
167 struct file
* vm_file
; /* File we map to (can be NULL). */
168 void * vm_private_data
; /* was vm_pte (shared mem) */
169 unsigned long vm_truncate_count
;/* truncate_count or restart_addr */
172 struct vm_region
*vm_region
; /* NOMMU mapping region */
175 struct mempolicy
*vm_policy
; /* NUMA policy for the VMA */
180 struct task_struct
*task
;
181 struct core_thread
*next
;
186 struct core_thread dumper
;
187 struct completion startup
;
191 struct vm_area_struct
* mmap
; /* list of VMAs */
192 struct rb_root mm_rb
;
193 struct vm_area_struct
* mmap_cache
; /* last find_vma result */
194 unsigned long (*get_unmapped_area
) (struct file
*filp
,
195 unsigned long addr
, unsigned long len
,
196 unsigned long pgoff
, unsigned long flags
);
197 void (*unmap_area
) (struct mm_struct
*mm
, unsigned long addr
);
198 unsigned long mmap_base
; /* base of mmap area */
199 unsigned long task_size
; /* size of task vm space */
200 unsigned long cached_hole_size
; /* if non-zero, the largest hole below free_area_cache */
201 unsigned long free_area_cache
; /* first hole of size cached_hole_size or larger */
203 atomic_t mm_users
; /* How many users with user space? */
204 atomic_t mm_count
; /* How many references to "struct mm_struct" (users count as 1) */
205 int map_count
; /* number of VMAs */
206 struct rw_semaphore mmap_sem
;
207 spinlock_t page_table_lock
; /* Protects page tables and some counters */
209 struct list_head mmlist
; /* List of maybe swapped mm's. These are globally strung
210 * together off init_mm.mmlist, and are protected
214 /* Special counters, in some configurations protected by the
215 * page_table_lock, in other configurations by being atomic.
217 mm_counter_t _file_rss
;
218 mm_counter_t _anon_rss
;
220 unsigned long hiwater_rss
; /* High-watermark of RSS usage */
221 unsigned long hiwater_vm
; /* High-water virtual memory usage */
223 unsigned long total_vm
, locked_vm
, shared_vm
, exec_vm
;
224 unsigned long stack_vm
, reserved_vm
, def_flags
, nr_ptes
;
225 unsigned long start_code
, end_code
, start_data
, end_data
;
226 unsigned long start_brk
, brk
, start_stack
;
227 unsigned long arg_start
, arg_end
, env_start
, env_end
;
229 unsigned long saved_auxv
[AT_VECTOR_SIZE
]; /* for /proc/PID/auxv */
231 cpumask_t cpu_vm_mask
;
233 /* Architecture-specific MM context */
234 mm_context_t context
;
236 /* Swap token stuff */
238 * Last value of global fault stamp as seen by this process.
239 * In other words, this value gives an indication of how long
240 * it has been since this task got the token.
241 * Look at mm/thrash.c
243 unsigned int faultstamp
;
244 unsigned int token_priority
;
245 unsigned int last_interval
;
247 unsigned long flags
; /* Must use atomic bitops to access the bits */
249 struct core_state
*core_state
; /* coredumping support */
252 spinlock_t ioctx_lock
;
253 struct hlist_head ioctx_list
;
255 #ifdef CONFIG_MM_OWNER
257 * "owner" points to a task that is regarded as the canonical
258 * user/owner of this mm. All of the following must be true in
259 * order for it to be changed:
261 * current == mm->owner
263 * new_owner->mm == mm
264 * new_owner->alloc_lock is held
266 struct task_struct
*owner
;
269 #ifdef CONFIG_PROC_FS
270 /* store ref to file /proc/<pid>/exe symlink points to */
271 struct file
*exe_file
;
272 unsigned long num_exe_file_vmas
;
274 #ifdef CONFIG_MMU_NOTIFIER
275 struct mmu_notifier_mm
*mmu_notifier_mm
;
279 #endif /* _LINUX_MM_TYPES_H */