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 <asm/page.h>
15#include <asm/mmu.h>
16
17#ifndef AT_VECTOR_SIZE_ARCH
18#define AT_VECTOR_SIZE_ARCH 0
19#endif
20#define AT_VECTOR_SIZE (2*(AT_VECTOR_SIZE_ARCH + AT_VECTOR_SIZE_BASE + 1))
21
22struct address_space;
23
24#define USE_SPLIT_PTLOCKS (NR_CPUS >= CONFIG_SPLIT_PTLOCK_CPUS)
25
26#if USE_SPLIT_PTLOCKS
27typedef atomic_long_t mm_counter_t;
28#else /* !USE_SPLIT_PTLOCKS */
29typedef unsigned long mm_counter_t;
30#endif /* !USE_SPLIT_PTLOCKS */
31
32/*
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
37 * who is mapping it.
38 */
39struct page {
40 unsigned long flags; /* Atomic flags, some possibly
41 * updated asynchronously */
42 atomic_t _count; /* Usage count, see below. */
43 union {
44 atomic_t _mapcount; /* Count of ptes mapped in mms,
45 * to show when page is mapped
46 * & limit reverse map searches.
47 */
48 struct { /* SLUB */
49 u16 inuse;
50 u16 objects;
51 };
52 };
53 union {
54 struct {
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.
61 */
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.
68 */
69 };
70#if USE_SPLIT_PTLOCKS
71 spinlock_t ptl;
72#endif
73 struct kmem_cache *slab; /* SLUB: Pointer to slab */
74 struct page *first_page; /* Compound tail pages */
75 };
76 union {
77 pgoff_t index; /* Our offset within mapping. */
78 void *freelist; /* SLUB: freelist req. slab lock */
79 };
80 struct list_head lru; /* Pageout list, eg. active_list
81 * protected by zone->lru_lock !
82 */
83 /*
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 ... ;)
89 *
90 * Architectures with slow multiplication can define
91 * WANT_PAGE_VIRTUAL in asm/page.h
92 */
93#if defined(WANT_PAGE_VIRTUAL)
94 void *virtual; /* Kernel virtual address (NULL if
95 not kmapped, ie. highmem) */
96#endif /* WANT_PAGE_VIRTUAL */
97};
98
99/*
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
102 * map parts of them.
103 */
104struct vm_region {
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 */
112
113 atomic_t vm_usage; /* region usage count */
114};
115
116/*
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).
121 */
122struct 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
126 within vm_mm. */
127
128 /* linked list of VM areas per task, sorted by address */
129 struct vm_area_struct *vm_next;
130
131 pgprot_t vm_page_prot; /* Access permissions of this VMA. */
132 unsigned long vm_flags; /* Flags, see mm.h. */
133
134 struct rb_node vm_rb;
135
136 /*
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.
141 */
142 union {
143 struct {
144 struct list_head list;
145 void *parent; /* aligns with prio_tree_node parent */
146 struct vm_area_struct *head;
147 } vm_set;
148
149 struct raw_prio_tree_node prio_tree_node;
150 } shared;
151
152 /*
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.
157 */
158 struct list_head anon_vma_node; /* Serialized by anon_vma->lock */
159 struct anon_vma *anon_vma; /* Serialized by page_table_lock */
160
161 /* Function pointers to deal with this struct. */
162 struct vm_operations_struct * vm_ops;
163
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 */
170
171#ifndef CONFIG_MMU
172 struct vm_region *vm_region; /* NOMMU mapping region */
173#endif
174#ifdef CONFIG_NUMA
175 struct mempolicy *vm_policy; /* NUMA policy for the VMA */
176#endif
177};
178
179struct core_thread {
180 struct task_struct *task;
181 struct core_thread *next;
182};
183
184struct core_state {
185 atomic_t nr_threads;
186 struct core_thread dumper;
187 struct completion startup;
188};
189
190struct mm_struct {
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 */
202 pgd_t * pgd;
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 */
208
209 struct list_head mmlist; /* List of maybe swapped mm's. These are globally strung
210 * together off init_mm.mmlist, and are protected
211 * by mmlist_lock
212 */
213
214 /* Special counters, in some configurations protected by the
215 * page_table_lock, in other configurations by being atomic.
216 */
217 mm_counter_t _file_rss;
218 mm_counter_t _anon_rss;
219
220 unsigned long hiwater_rss; /* High-watermark of RSS usage */
221 unsigned long hiwater_vm; /* High-water virtual memory usage */
222
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;
228
229 unsigned long saved_auxv[AT_VECTOR_SIZE]; /* for /proc/PID/auxv */
230
231 cpumask_t cpu_vm_mask;
232
233 /* Architecture-specific MM context */
234 mm_context_t context;
235
236 /* Swap token stuff */
237 /*
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
242 */
243 unsigned int faultstamp;
244 unsigned int token_priority;
245 unsigned int last_interval;
246
247 unsigned long flags; /* Must use atomic bitops to access the bits */
248
249 struct core_state *core_state; /* coredumping support */
250
251 /* aio bits */
252 spinlock_t ioctx_lock;
253 struct hlist_head ioctx_list;
254
255#ifdef CONFIG_MM_OWNER
256 /*
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:
260 *
261 * current == mm->owner
262 * current->mm != mm
263 * new_owner->mm == mm
264 * new_owner->alloc_lock is held
265 */
266 struct task_struct *owner;
267#endif
268
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;
273#endif
274#ifdef CONFIG_MMU_NOTIFIER
275 struct mmu_notifier_mm *mmu_notifier_mm;
276#endif
277};
278
279/* Future-safe accessor for struct mm_struct's cpu_vm_mask. */
280#define mm_cpumask(mm) (&(mm)->cpu_vm_mask)
281
282#endif /* _LINUX_MM_TYPES_H */