Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
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 <asm/page.h>
14#include <asm/mmu.h>
15
16#ifndef AT_VECTOR_SIZE_ARCH
17#define AT_VECTOR_SIZE_ARCH 0
18#endif
19#define AT_VECTOR_SIZE (2*(AT_VECTOR_SIZE_ARCH + AT_VECTOR_SIZE_BASE + 1))
20
21struct address_space;
22
23#if NR_CPUS >= CONFIG_SPLIT_PTLOCK_CPUS
24typedef atomic_long_t mm_counter_t;
25#else /* NR_CPUS < CONFIG_SPLIT_PTLOCK_CPUS */
26typedef unsigned long mm_counter_t;
27#endif /* NR_CPUS < CONFIG_SPLIT_PTLOCK_CPUS */
28
29/*
30 * Each physical page in the system has a struct page associated with
31 * it to keep track of whatever it is we are using the page for at the
32 * moment. Note that we have no way to track which tasks are using
33 * a page, though if it is a pagecache page, rmap structures can tell us
34 * who is mapping it.
35 */
36struct page {
37 unsigned long flags; /* Atomic flags, some possibly
38 * updated asynchronously */
39 atomic_t _count; /* Usage count, see below. */
40 union {
41 atomic_t _mapcount; /* Count of ptes mapped in mms,
42 * to show when page is mapped
43 * & limit reverse map searches.
44 */
45 unsigned int inuse; /* SLUB: Nr of objects */
46 };
47 union {
48 struct {
49 unsigned long private; /* Mapping-private opaque data:
50 * usually used for buffer_heads
51 * if PagePrivate set; used for
52 * swp_entry_t if PageSwapCache;
53 * indicates order in the buddy
54 * system if PG_buddy is set.
55 */
56 struct address_space *mapping; /* If low bit clear, points to
57 * inode address_space, or NULL.
58 * If page mapped as anonymous
59 * memory, low bit is set, and
60 * it points to anon_vma object:
61 * see PAGE_MAPPING_ANON below.
62 */
63 };
64#if NR_CPUS >= CONFIG_SPLIT_PTLOCK_CPUS
65 spinlock_t ptl;
66#endif
67 struct kmem_cache *slab; /* SLUB: Pointer to slab */
68 struct page *first_page; /* Compound tail pages */
69 };
70 union {
71 pgoff_t index; /* Our offset within mapping. */
72 void *freelist; /* SLUB: freelist req. slab lock */
73 };
74 struct list_head lru; /* Pageout list, eg. active_list
75 * protected by zone->lru_lock !
76 */
77 /*
78 * On machines where all RAM is mapped into kernel address space,
79 * we can simply calculate the virtual address. On machines with
80 * highmem some memory is mapped into kernel virtual memory
81 * dynamically, so we need a place to store that address.
82 * Note that this field could be 16 bits on x86 ... ;)
83 *
84 * Architectures with slow multiplication can define
85 * WANT_PAGE_VIRTUAL in asm/page.h
86 */
87#if defined(WANT_PAGE_VIRTUAL)
88 void *virtual; /* Kernel virtual address (NULL if
89 not kmapped, ie. highmem) */
90#endif /* WANT_PAGE_VIRTUAL */
91#ifdef CONFIG_CGROUP_MEM_RES_CTLR
92 unsigned long page_cgroup;
93#endif
94};
95
96/*
97 * This struct defines a memory VMM memory area. There is one of these
98 * per VM-area/task. A VM area is any part of the process virtual memory
99 * space that has a special rule for the page-fault handlers (ie a shared
100 * library, the executable area etc).
101 */
102struct vm_area_struct {
103 struct mm_struct * vm_mm; /* The address space we belong to. */
104 unsigned long vm_start; /* Our start address within vm_mm. */
105 unsigned long vm_end; /* The first byte after our end address
106 within vm_mm. */
107
108 /* linked list of VM areas per task, sorted by address */
109 struct vm_area_struct *vm_next;
110
111 pgprot_t vm_page_prot; /* Access permissions of this VMA. */
112 unsigned long vm_flags; /* Flags, listed below. */
113
114 struct rb_node vm_rb;
115
116 /*
117 * For areas with an address space and backing store,
118 * linkage into the address_space->i_mmap prio tree, or
119 * linkage to the list of like vmas hanging off its node, or
120 * linkage of vma in the address_space->i_mmap_nonlinear list.
121 */
122 union {
123 struct {
124 struct list_head list;
125 void *parent; /* aligns with prio_tree_node parent */
126 struct vm_area_struct *head;
127 } vm_set;
128
129 struct raw_prio_tree_node prio_tree_node;
130 } shared;
131
132 /*
133 * A file's MAP_PRIVATE vma can be in both i_mmap tree and anon_vma
134 * list, after a COW of one of the file pages. A MAP_SHARED vma
135 * can only be in the i_mmap tree. An anonymous MAP_PRIVATE, stack
136 * or brk vma (with NULL file) can only be in an anon_vma list.
137 */
138 struct list_head anon_vma_node; /* Serialized by anon_vma->lock */
139 struct anon_vma *anon_vma; /* Serialized by page_table_lock */
140
141 /* Function pointers to deal with this struct. */
142 struct vm_operations_struct * vm_ops;
143
144 /* Information about our backing store: */
145 unsigned long vm_pgoff; /* Offset (within vm_file) in PAGE_SIZE
146 units, *not* PAGE_CACHE_SIZE */
147 struct file * vm_file; /* File we map to (can be NULL). */
148 void * vm_private_data; /* was vm_pte (shared mem) */
149 unsigned long vm_truncate_count;/* truncate_count or restart_addr */
150
151#ifndef CONFIG_MMU
152 atomic_t vm_usage; /* refcount (VMAs shared if !MMU) */
153#endif
154#ifdef CONFIG_NUMA
155 struct mempolicy *vm_policy; /* NUMA policy for the VMA */
156#endif
157};
158
159struct mm_struct {
160 struct vm_area_struct * mmap; /* list of VMAs */
161 struct rb_root mm_rb;
162 struct vm_area_struct * mmap_cache; /* last find_vma result */
163 unsigned long (*get_unmapped_area) (struct file *filp,
164 unsigned long addr, unsigned long len,
165 unsigned long pgoff, unsigned long flags);
166 void (*unmap_area) (struct mm_struct *mm, unsigned long addr);
167 unsigned long mmap_base; /* base of mmap area */
168 unsigned long task_size; /* size of task vm space */
169 unsigned long cached_hole_size; /* if non-zero, the largest hole below free_area_cache */
170 unsigned long free_area_cache; /* first hole of size cached_hole_size or larger */
171 pgd_t * pgd;
172 atomic_t mm_users; /* How many users with user space? */
173 atomic_t mm_count; /* How many references to "struct mm_struct" (users count as 1) */
174 int map_count; /* number of VMAs */
175 struct rw_semaphore mmap_sem;
176 spinlock_t page_table_lock; /* Protects page tables and some counters */
177
178 struct list_head mmlist; /* List of maybe swapped mm's. These are globally strung
179 * together off init_mm.mmlist, and are protected
180 * by mmlist_lock
181 */
182
183 /* Special counters, in some configurations protected by the
184 * page_table_lock, in other configurations by being atomic.
185 */
186 mm_counter_t _file_rss;
187 mm_counter_t _anon_rss;
188
189 unsigned long hiwater_rss; /* High-watermark of RSS usage */
190 unsigned long hiwater_vm; /* High-water virtual memory usage */
191
192 unsigned long total_vm, locked_vm, shared_vm, exec_vm;
193 unsigned long stack_vm, reserved_vm, def_flags, nr_ptes;
194 unsigned long start_code, end_code, start_data, end_data;
195 unsigned long start_brk, brk, start_stack;
196 unsigned long arg_start, arg_end, env_start, env_end;
197
198 unsigned long saved_auxv[AT_VECTOR_SIZE]; /* for /proc/PID/auxv */
199
200 cpumask_t cpu_vm_mask;
201
202 /* Architecture-specific MM context */
203 mm_context_t context;
204
205 /* Swap token stuff */
206 /*
207 * Last value of global fault stamp as seen by this process.
208 * In other words, this value gives an indication of how long
209 * it has been since this task got the token.
210 * Look at mm/thrash.c
211 */
212 unsigned int faultstamp;
213 unsigned int token_priority;
214 unsigned int last_interval;
215
216 unsigned long flags; /* Must use atomic bitops to access the bits */
217
218 /* coredumping support */
219 int core_waiters;
220 struct completion *core_startup_done, core_done;
221
222 /* aio bits */
223 rwlock_t ioctx_list_lock;
224 struct kioctx *ioctx_list;
225#ifdef CONFIG_CGROUP_MEM_RES_CTLR
226 struct mem_cgroup *mem_cgroup;
227#endif
228};
229
230#endif /* _LINUX_MM_TYPES_H */