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 23 struct address_space; 24 25 #define USE_SPLIT_PTLOCKS (NR_CPUS >= CONFIG_SPLIT_PTLOCK_CPUS) 26 27 #if USE_SPLIT_PTLOCKS 28 typedef atomic_long_t mm_counter_t; 29 #else /* !USE_SPLIT_PTLOCKS */ 30 typedef 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 */ 40 struct 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 #ifdef CONFIG_KMEMCHECK 103 /* 104 * kmemcheck wants to track the status of each byte in a page; this 105 * is a pointer to such a status block. NULL if not tracked. 106 */ 107 void *shadow; 108 #endif 109 }; 110 111 /* 112 * A region containing a mapping of a non-memory backed file under NOMMU 113 * conditions. These are held in a global tree and are pinned by the VMAs that 114 * map parts of them. 115 */ 116 struct vm_region { 117 struct rb_node vm_rb; /* link in global region tree */ 118 unsigned long vm_flags; /* VMA vm_flags */ 119 unsigned long vm_start; /* start address of region */ 120 unsigned long vm_end; /* region initialised to here */ 121 unsigned long vm_top; /* region allocated to here */ 122 unsigned long vm_pgoff; /* the offset in vm_file corresponding to vm_start */ 123 struct file *vm_file; /* the backing file or NULL */ 124 125 int vm_usage; /* region usage count (access under nommu_region_sem) */ 126 bool vm_icache_flushed : 1; /* true if the icache has been flushed for 127 * this region */ 128 }; 129 130 /* 131 * This struct defines a memory VMM memory area. There is one of these 132 * per VM-area/task. A VM area is any part of the process virtual memory 133 * space that has a special rule for the page-fault handlers (ie a shared 134 * library, the executable area etc). 135 */ 136 struct vm_area_struct { 137 struct mm_struct * vm_mm; /* The address space we belong to. */ 138 unsigned long vm_start; /* Our start address within vm_mm. */ 139 unsigned long vm_end; /* The first byte after our end address 140 within vm_mm. */ 141 142 /* linked list of VM areas per task, sorted by address */ 143 struct vm_area_struct *vm_next; 144 145 pgprot_t vm_page_prot; /* Access permissions of this VMA. */ 146 unsigned long vm_flags; /* Flags, see mm.h. */ 147 148 struct rb_node vm_rb; 149 150 /* 151 * For areas with an address space and backing store, 152 * linkage into the address_space->i_mmap prio tree, or 153 * linkage to the list of like vmas hanging off its node, or 154 * linkage of vma in the address_space->i_mmap_nonlinear list. 155 */ 156 union { 157 struct { 158 struct list_head list; 159 void *parent; /* aligns with prio_tree_node parent */ 160 struct vm_area_struct *head; 161 } vm_set; 162 163 struct raw_prio_tree_node prio_tree_node; 164 } shared; 165 166 /* 167 * A file's MAP_PRIVATE vma can be in both i_mmap tree and anon_vma 168 * list, after a COW of one of the file pages. A MAP_SHARED vma 169 * can only be in the i_mmap tree. An anonymous MAP_PRIVATE, stack 170 * or brk vma (with NULL file) can only be in an anon_vma list. 171 */ 172 struct list_head anon_vma_node; /* Serialized by anon_vma->lock */ 173 struct anon_vma *anon_vma; /* Serialized by page_table_lock */ 174 175 /* Function pointers to deal with this struct. */ 176 const struct vm_operations_struct *vm_ops; 177 178 /* Information about our backing store: */ 179 unsigned long vm_pgoff; /* Offset (within vm_file) in PAGE_SIZE 180 units, *not* PAGE_CACHE_SIZE */ 181 struct file * vm_file; /* File we map to (can be NULL). */ 182 void * vm_private_data; /* was vm_pte (shared mem) */ 183 unsigned long vm_truncate_count;/* truncate_count or restart_addr */ 184 185 #ifndef CONFIG_MMU 186 struct vm_region *vm_region; /* NOMMU mapping region */ 187 #endif 188 #ifdef CONFIG_NUMA 189 struct mempolicy *vm_policy; /* NUMA policy for the VMA */ 190 #endif 191 }; 192 193 struct core_thread { 194 struct task_struct *task; 195 struct core_thread *next; 196 }; 197 198 struct core_state { 199 atomic_t nr_threads; 200 struct core_thread dumper; 201 struct completion startup; 202 }; 203 204 struct mm_struct { 205 struct vm_area_struct * mmap; /* list of VMAs */ 206 struct rb_root mm_rb; 207 struct vm_area_struct * mmap_cache; /* last find_vma result */ 208 #ifdef CONFIG_MMU 209 unsigned long (*get_unmapped_area) (struct file *filp, 210 unsigned long addr, unsigned long len, 211 unsigned long pgoff, unsigned long flags); 212 void (*unmap_area) (struct mm_struct *mm, unsigned long addr); 213 #endif 214 unsigned long mmap_base; /* base of mmap area */ 215 unsigned long task_size; /* size of task vm space */ 216 unsigned long cached_hole_size; /* if non-zero, the largest hole below free_area_cache */ 217 unsigned long free_area_cache; /* first hole of size cached_hole_size or larger */ 218 pgd_t * pgd; 219 atomic_t mm_users; /* How many users with user space? */ 220 atomic_t mm_count; /* How many references to "struct mm_struct" (users count as 1) */ 221 int map_count; /* number of VMAs */ 222 struct rw_semaphore mmap_sem; 223 spinlock_t page_table_lock; /* Protects page tables and some counters */ 224 225 struct list_head mmlist; /* List of maybe swapped mm's. These are globally strung 226 * together off init_mm.mmlist, and are protected 227 * by mmlist_lock 228 */ 229 230 /* Special counters, in some configurations protected by the 231 * page_table_lock, in other configurations by being atomic. 232 */ 233 mm_counter_t _file_rss; 234 mm_counter_t _anon_rss; 235 236 unsigned long hiwater_rss; /* High-watermark of RSS usage */ 237 unsigned long hiwater_vm; /* High-water virtual memory usage */ 238 239 unsigned long total_vm, locked_vm, shared_vm, exec_vm; 240 unsigned long stack_vm, reserved_vm, def_flags, nr_ptes; 241 unsigned long start_code, end_code, start_data, end_data; 242 unsigned long start_brk, brk, start_stack; 243 unsigned long arg_start, arg_end, env_start, env_end; 244 245 unsigned long saved_auxv[AT_VECTOR_SIZE]; /* for /proc/PID/auxv */ 246 247 struct linux_binfmt *binfmt; 248 249 cpumask_t cpu_vm_mask; 250 251 /* Architecture-specific MM context */ 252 mm_context_t context; 253 254 /* Swap token stuff */ 255 /* 256 * Last value of global fault stamp as seen by this process. 257 * In other words, this value gives an indication of how long 258 * it has been since this task got the token. 259 * Look at mm/thrash.c 260 */ 261 unsigned int faultstamp; 262 unsigned int token_priority; 263 unsigned int last_interval; 264 265 unsigned long flags; /* Must use atomic bitops to access the bits */ 266 267 struct core_state *core_state; /* coredumping support */ 268 #ifdef CONFIG_AIO 269 spinlock_t ioctx_lock; 270 struct hlist_head ioctx_list; 271 #endif 272 #ifdef CONFIG_MM_OWNER 273 /* 274 * "owner" points to a task that is regarded as the canonical 275 * user/owner of this mm. All of the following must be true in 276 * order for it to be changed: 277 * 278 * current == mm->owner 279 * current->mm != mm 280 * new_owner->mm == mm 281 * new_owner->alloc_lock is held 282 */ 283 struct task_struct *owner; 284 #endif 285 286 #ifdef CONFIG_PROC_FS 287 /* store ref to file /proc/<pid>/exe symlink points to */ 288 struct file *exe_file; 289 unsigned long num_exe_file_vmas; 290 #endif 291 #ifdef CONFIG_MMU_NOTIFIER 292 struct mmu_notifier_mm *mmu_notifier_mm; 293 #endif 294 }; 295 296 /* Future-safe accessor for struct mm_struct's cpu_vm_mask. */ 297 #define mm_cpumask(mm) (&(mm)->cpu_vm_mask) 298 299 #endif /* _LINUX_MM_TYPES_H */ 300