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