Linux kernel mirror (for testing)
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1#ifndef _LINUX_MM_TYPES_H
2#define _LINUX_MM_TYPES_H
3
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>
14#include <linux/page-debug-flags.h>
15#include <asm/page.h>
16#include <asm/mmu.h>
17
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
23struct address_space;
24
25#define USE_SPLIT_PTLOCKS (NR_CPUS >= CONFIG_SPLIT_PTLOCK_CPUS)
26
27#if USE_SPLIT_PTLOCKS
28typedef atomic_long_t mm_counter_t;
29#else /* !USE_SPLIT_PTLOCKS */
30typedef unsigned long mm_counter_t;
31#endif /* !USE_SPLIT_PTLOCKS */
32
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 */
40struct page {
41 unsigned long flags; /* Atomic flags, some possibly
42 * updated asynchronously */
43 atomic_t _count; /* Usage count, see below. */
44 union {
45 atomic_t _mapcount; /* Count of ptes mapped in mms,
46 * to show when page is mapped
47 * & limit reverse map searches.
48 */
49 struct { /* SLUB */
50 u16 inuse;
51 u16 objects;
52 };
53 };
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 };
71#if USE_SPLIT_PTLOCKS
72 spinlock_t ptl;
73#endif
74 struct kmem_cache *slab; /* SLUB: Pointer to slab */
75 struct page *first_page; /* Compound tail pages */
76 };
77 union {
78 pgoff_t index; /* Our offset within mapping. */
79 void *freelist; /* SLUB: freelist req. slab lock */
80 };
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 */
98#ifdef CONFIG_WANT_PAGE_DEBUG_FLAGS
99 unsigned long debug_flags; /* Use atomic bitops on this */
100#endif
101};
102
103/*
104 * A region containing a mapping of a non-memory backed file under NOMMU
105 * conditions. These are held in a global tree and are pinned by the VMAs that
106 * map parts of them.
107 */
108struct vm_region {
109 struct rb_node vm_rb; /* link in global region tree */
110 unsigned long vm_flags; /* VMA vm_flags */
111 unsigned long vm_start; /* start address of region */
112 unsigned long vm_end; /* region initialised to here */
113 unsigned long vm_top; /* region allocated to here */
114 unsigned long vm_pgoff; /* the offset in vm_file corresponding to vm_start */
115 struct file *vm_file; /* the backing file or NULL */
116
117 atomic_t vm_usage; /* region usage count */
118};
119
120/*
121 * This struct defines a memory VMM memory area. There is one of these
122 * per VM-area/task. A VM area is any part of the process virtual memory
123 * space that has a special rule for the page-fault handlers (ie a shared
124 * library, the executable area etc).
125 */
126struct vm_area_struct {
127 struct mm_struct * vm_mm; /* The address space we belong to. */
128 unsigned long vm_start; /* Our start address within vm_mm. */
129 unsigned long vm_end; /* The first byte after our end address
130 within vm_mm. */
131
132 /* linked list of VM areas per task, sorted by address */
133 struct vm_area_struct *vm_next;
134
135 pgprot_t vm_page_prot; /* Access permissions of this VMA. */
136 unsigned long vm_flags; /* Flags, see mm.h. */
137
138 struct rb_node vm_rb;
139
140 /*
141 * For areas with an address space and backing store,
142 * linkage into the address_space->i_mmap prio tree, or
143 * linkage to the list of like vmas hanging off its node, or
144 * linkage of vma in the address_space->i_mmap_nonlinear list.
145 */
146 union {
147 struct {
148 struct list_head list;
149 void *parent; /* aligns with prio_tree_node parent */
150 struct vm_area_struct *head;
151 } vm_set;
152
153 struct raw_prio_tree_node prio_tree_node;
154 } shared;
155
156 /*
157 * A file's MAP_PRIVATE vma can be in both i_mmap tree and anon_vma
158 * list, after a COW of one of the file pages. A MAP_SHARED vma
159 * can only be in the i_mmap tree. An anonymous MAP_PRIVATE, stack
160 * or brk vma (with NULL file) can only be in an anon_vma list.
161 */
162 struct list_head anon_vma_node; /* Serialized by anon_vma->lock */
163 struct anon_vma *anon_vma; /* Serialized by page_table_lock */
164
165 /* Function pointers to deal with this struct. */
166 struct vm_operations_struct * vm_ops;
167
168 /* Information about our backing store: */
169 unsigned long vm_pgoff; /* Offset (within vm_file) in PAGE_SIZE
170 units, *not* PAGE_CACHE_SIZE */
171 struct file * vm_file; /* File we map to (can be NULL). */
172 void * vm_private_data; /* was vm_pte (shared mem) */
173 unsigned long vm_truncate_count;/* truncate_count or restart_addr */
174
175#ifndef CONFIG_MMU
176 struct vm_region *vm_region; /* NOMMU mapping region */
177#endif
178#ifdef CONFIG_NUMA
179 struct mempolicy *vm_policy; /* NUMA policy for the VMA */
180#endif
181};
182
183struct core_thread {
184 struct task_struct *task;
185 struct core_thread *next;
186};
187
188struct core_state {
189 atomic_t nr_threads;
190 struct core_thread dumper;
191 struct completion startup;
192};
193
194struct mm_struct {
195 struct vm_area_struct * mmap; /* list of VMAs */
196 struct rb_root mm_rb;
197 struct vm_area_struct * mmap_cache; /* last find_vma result */
198 unsigned long (*get_unmapped_area) (struct file *filp,
199 unsigned long addr, unsigned long len,
200 unsigned long pgoff, unsigned long flags);
201 void (*unmap_area) (struct mm_struct *mm, unsigned long addr);
202 unsigned long mmap_base; /* base of mmap area */
203 unsigned long task_size; /* size of task vm space */
204 unsigned long cached_hole_size; /* if non-zero, the largest hole below free_area_cache */
205 unsigned long free_area_cache; /* first hole of size cached_hole_size or larger */
206 pgd_t * pgd;
207 atomic_t mm_users; /* How many users with user space? */
208 atomic_t mm_count; /* How many references to "struct mm_struct" (users count as 1) */
209 int map_count; /* number of VMAs */
210 struct rw_semaphore mmap_sem;
211 spinlock_t page_table_lock; /* Protects page tables and some counters */
212
213 struct list_head mmlist; /* List of maybe swapped mm's. These are globally strung
214 * together off init_mm.mmlist, and are protected
215 * by mmlist_lock
216 */
217
218 /* Special counters, in some configurations protected by the
219 * page_table_lock, in other configurations by being atomic.
220 */
221 mm_counter_t _file_rss;
222 mm_counter_t _anon_rss;
223
224 unsigned long hiwater_rss; /* High-watermark of RSS usage */
225 unsigned long hiwater_vm; /* High-water virtual memory usage */
226
227 unsigned long total_vm, locked_vm, shared_vm, exec_vm;
228 unsigned long stack_vm, reserved_vm, def_flags, nr_ptes;
229 unsigned long start_code, end_code, start_data, end_data;
230 unsigned long start_brk, brk, start_stack;
231 unsigned long arg_start, arg_end, env_start, env_end;
232
233 unsigned long saved_auxv[AT_VECTOR_SIZE]; /* for /proc/PID/auxv */
234
235 cpumask_t cpu_vm_mask;
236
237 /* Architecture-specific MM context */
238 mm_context_t context;
239
240 /* Swap token stuff */
241 /*
242 * Last value of global fault stamp as seen by this process.
243 * In other words, this value gives an indication of how long
244 * it has been since this task got the token.
245 * Look at mm/thrash.c
246 */
247 unsigned int faultstamp;
248 unsigned int token_priority;
249 unsigned int last_interval;
250
251 unsigned long flags; /* Must use atomic bitops to access the bits */
252
253 struct core_state *core_state; /* coredumping support */
254
255 /* aio bits */
256 spinlock_t ioctx_lock;
257 struct hlist_head ioctx_list;
258
259#ifdef CONFIG_MM_OWNER
260 /*
261 * "owner" points to a task that is regarded as the canonical
262 * user/owner of this mm. All of the following must be true in
263 * order for it to be changed:
264 *
265 * current == mm->owner
266 * current->mm != mm
267 * new_owner->mm == mm
268 * new_owner->alloc_lock is held
269 */
270 struct task_struct *owner;
271#endif
272
273#ifdef CONFIG_PROC_FS
274 /* store ref to file /proc/<pid>/exe symlink points to */
275 struct file *exe_file;
276 unsigned long num_exe_file_vmas;
277#endif
278#ifdef CONFIG_MMU_NOTIFIER
279 struct mmu_notifier_mm *mmu_notifier_mm;
280#endif
281};
282
283/* Future-safe accessor for struct mm_struct's cpu_vm_mask. */
284#define mm_cpumask(mm) (&(mm)->cpu_vm_mask)
285
286#endif /* _LINUX_MM_TYPES_H */