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/* 28 * Each physical page in the system has a struct page associated with 29 * it to keep track of whatever it is we are using the page for at the 30 * moment. Note that we have no way to track which tasks are using 31 * a page, though if it is a pagecache page, rmap structures can tell us 32 * who is mapping it. 33 */ 34struct page { 35 unsigned long flags; /* Atomic flags, some possibly 36 * updated asynchronously */ 37 atomic_t _count; /* Usage count, see below. */ 38 union { 39 atomic_t _mapcount; /* Count of ptes mapped in mms, 40 * to show when page is mapped 41 * & limit reverse map searches. 42 */ 43 struct { /* SLUB */ 44 u16 inuse; 45 u16 objects; 46 }; 47 }; 48 union { 49 struct { 50 unsigned long private; /* Mapping-private opaque data: 51 * usually used for buffer_heads 52 * if PagePrivate set; used for 53 * swp_entry_t if PageSwapCache; 54 * indicates order in the buddy 55 * system if PG_buddy is set. 56 */ 57 struct address_space *mapping; /* If low bit clear, points to 58 * inode address_space, or NULL. 59 * If page mapped as anonymous 60 * memory, low bit is set, and 61 * it points to anon_vma object: 62 * see PAGE_MAPPING_ANON below. 63 */ 64 }; 65#if USE_SPLIT_PTLOCKS 66 spinlock_t ptl; 67#endif 68 struct kmem_cache *slab; /* SLUB: Pointer to slab */ 69 struct page *first_page; /* Compound tail pages */ 70 }; 71 union { 72 pgoff_t index; /* Our offset within mapping. */ 73 void *freelist; /* SLUB: freelist req. slab lock */ 74 }; 75 struct list_head lru; /* Pageout list, eg. active_list 76 * protected by zone->lru_lock ! 77 */ 78 /* 79 * On machines where all RAM is mapped into kernel address space, 80 * we can simply calculate the virtual address. On machines with 81 * highmem some memory is mapped into kernel virtual memory 82 * dynamically, so we need a place to store that address. 83 * Note that this field could be 16 bits on x86 ... ;) 84 * 85 * Architectures with slow multiplication can define 86 * WANT_PAGE_VIRTUAL in asm/page.h 87 */ 88#if defined(WANT_PAGE_VIRTUAL) 89 void *virtual; /* Kernel virtual address (NULL if 90 not kmapped, ie. highmem) */ 91#endif /* WANT_PAGE_VIRTUAL */ 92#ifdef CONFIG_WANT_PAGE_DEBUG_FLAGS 93 unsigned long debug_flags; /* Use atomic bitops on this */ 94#endif 95 96#ifdef CONFIG_KMEMCHECK 97 /* 98 * kmemcheck wants to track the status of each byte in a page; this 99 * is a pointer to such a status block. NULL if not tracked. 100 */ 101 void *shadow; 102#endif 103}; 104 105/* 106 * A region containing a mapping of a non-memory backed file under NOMMU 107 * conditions. These are held in a global tree and are pinned by the VMAs that 108 * map parts of them. 109 */ 110struct vm_region { 111 struct rb_node vm_rb; /* link in global region tree */ 112 unsigned long vm_flags; /* VMA vm_flags */ 113 unsigned long vm_start; /* start address of region */ 114 unsigned long vm_end; /* region initialised to here */ 115 unsigned long vm_top; /* region allocated to here */ 116 unsigned long vm_pgoff; /* the offset in vm_file corresponding to vm_start */ 117 struct file *vm_file; /* the backing file or NULL */ 118 119 int vm_usage; /* region usage count (access under nommu_region_sem) */ 120 bool vm_icache_flushed : 1; /* true if the icache has been flushed for 121 * this region */ 122}; 123 124/* 125 * This struct defines a memory VMM memory area. There is one of these 126 * per VM-area/task. A VM area is any part of the process virtual memory 127 * space that has a special rule for the page-fault handlers (ie a shared 128 * library, the executable area etc). 129 */ 130struct vm_area_struct { 131 struct mm_struct * vm_mm; /* The address space we belong to. */ 132 unsigned long vm_start; /* Our start address within vm_mm. */ 133 unsigned long vm_end; /* The first byte after our end address 134 within vm_mm. */ 135 136 /* linked list of VM areas per task, sorted by address */ 137 struct vm_area_struct *vm_next, *vm_prev; 138 139 pgprot_t vm_page_prot; /* Access permissions of this VMA. */ 140 unsigned long vm_flags; /* Flags, see mm.h. */ 141 142 struct rb_node vm_rb; 143 144 /* 145 * For areas with an address space and backing store, 146 * linkage into the address_space->i_mmap prio tree, or 147 * linkage to the list of like vmas hanging off its node, or 148 * linkage of vma in the address_space->i_mmap_nonlinear list. 149 */ 150 union { 151 struct { 152 struct list_head list; 153 void *parent; /* aligns with prio_tree_node parent */ 154 struct vm_area_struct *head; 155 } vm_set; 156 157 struct raw_prio_tree_node prio_tree_node; 158 } shared; 159 160 /* 161 * A file's MAP_PRIVATE vma can be in both i_mmap tree and anon_vma 162 * list, after a COW of one of the file pages. A MAP_SHARED vma 163 * can only be in the i_mmap tree. An anonymous MAP_PRIVATE, stack 164 * or brk vma (with NULL file) can only be in an anon_vma list. 165 */ 166 struct list_head anon_vma_chain; /* Serialized by mmap_sem & 167 * page_table_lock */ 168 struct anon_vma *anon_vma; /* Serialized by page_table_lock */ 169 170 /* Function pointers to deal with this struct. */ 171 const struct vm_operations_struct *vm_ops; 172 173 /* Information about our backing store: */ 174 unsigned long vm_pgoff; /* Offset (within vm_file) in PAGE_SIZE 175 units, *not* PAGE_CACHE_SIZE */ 176 struct file * vm_file; /* File we map to (can be NULL). */ 177 void * vm_private_data; /* was vm_pte (shared mem) */ 178 unsigned long vm_truncate_count;/* truncate_count or restart_addr */ 179 180#ifndef CONFIG_MMU 181 struct vm_region *vm_region; /* NOMMU mapping region */ 182#endif 183#ifdef CONFIG_NUMA 184 struct mempolicy *vm_policy; /* NUMA policy for the VMA */ 185#endif 186}; 187 188struct core_thread { 189 struct task_struct *task; 190 struct core_thread *next; 191}; 192 193struct core_state { 194 atomic_t nr_threads; 195 struct core_thread dumper; 196 struct completion startup; 197}; 198 199enum { 200 MM_FILEPAGES, 201 MM_ANONPAGES, 202 MM_SWAPENTS, 203 NR_MM_COUNTERS 204}; 205 206#if USE_SPLIT_PTLOCKS && defined(CONFIG_MMU) 207#define SPLIT_RSS_COUNTING 208struct mm_rss_stat { 209 atomic_long_t count[NR_MM_COUNTERS]; 210}; 211/* per-thread cached information, */ 212struct task_rss_stat { 213 int events; /* for synchronization threshold */ 214 int count[NR_MM_COUNTERS]; 215}; 216#else /* !USE_SPLIT_PTLOCKS */ 217struct mm_rss_stat { 218 unsigned long count[NR_MM_COUNTERS]; 219}; 220#endif /* !USE_SPLIT_PTLOCKS */ 221 222struct mm_struct { 223 struct vm_area_struct * mmap; /* list of VMAs */ 224 struct rb_root mm_rb; 225 struct vm_area_struct * mmap_cache; /* last find_vma result */ 226#ifdef CONFIG_MMU 227 unsigned long (*get_unmapped_area) (struct file *filp, 228 unsigned long addr, unsigned long len, 229 unsigned long pgoff, unsigned long flags); 230 void (*unmap_area) (struct mm_struct *mm, unsigned long addr); 231#endif 232 unsigned long mmap_base; /* base of mmap area */ 233 unsigned long task_size; /* size of task vm space */ 234 unsigned long cached_hole_size; /* if non-zero, the largest hole below free_area_cache */ 235 unsigned long free_area_cache; /* first hole of size cached_hole_size or larger */ 236 pgd_t * pgd; 237 atomic_t mm_users; /* How many users with user space? */ 238 atomic_t mm_count; /* How many references to "struct mm_struct" (users count as 1) */ 239 int map_count; /* number of VMAs */ 240 241 spinlock_t page_table_lock; /* Protects page tables and some counters */ 242 struct rw_semaphore mmap_sem; 243 244 struct list_head mmlist; /* List of maybe swapped mm's. These are globally strung 245 * together off init_mm.mmlist, and are protected 246 * by mmlist_lock 247 */ 248 249 250 unsigned long hiwater_rss; /* High-watermark of RSS usage */ 251 unsigned long hiwater_vm; /* High-water virtual memory usage */ 252 253 unsigned long total_vm, locked_vm, shared_vm, exec_vm; 254 unsigned long stack_vm, reserved_vm, def_flags, nr_ptes; 255 unsigned long start_code, end_code, start_data, end_data; 256 unsigned long start_brk, brk, start_stack; 257 unsigned long arg_start, arg_end, env_start, env_end; 258 259 unsigned long saved_auxv[AT_VECTOR_SIZE]; /* for /proc/PID/auxv */ 260 261 /* 262 * Special counters, in some configurations protected by the 263 * page_table_lock, in other configurations by being atomic. 264 */ 265 struct mm_rss_stat rss_stat; 266 267 struct linux_binfmt *binfmt; 268 269 cpumask_t cpu_vm_mask; 270 271 /* Architecture-specific MM context */ 272 mm_context_t context; 273 274 /* Swap token stuff */ 275 /* 276 * Last value of global fault stamp as seen by this process. 277 * In other words, this value gives an indication of how long 278 * it has been since this task got the token. 279 * Look at mm/thrash.c 280 */ 281 unsigned int faultstamp; 282 unsigned int token_priority; 283 unsigned int last_interval; 284 285 /* How many tasks sharing this mm are OOM_DISABLE */ 286 atomic_t oom_disable_count; 287 288 unsigned long flags; /* Must use atomic bitops to access the bits */ 289 290 struct core_state *core_state; /* coredumping support */ 291#ifdef CONFIG_AIO 292 spinlock_t ioctx_lock; 293 struct hlist_head ioctx_list; 294#endif 295#ifdef CONFIG_MM_OWNER 296 /* 297 * "owner" points to a task that is regarded as the canonical 298 * user/owner of this mm. All of the following must be true in 299 * order for it to be changed: 300 * 301 * current == mm->owner 302 * current->mm != mm 303 * new_owner->mm == mm 304 * new_owner->alloc_lock is held 305 */ 306 struct task_struct __rcu *owner; 307#endif 308 309#ifdef CONFIG_PROC_FS 310 /* store ref to file /proc/<pid>/exe symlink points to */ 311 struct file *exe_file; 312 unsigned long num_exe_file_vmas; 313#endif 314#ifdef CONFIG_MMU_NOTIFIER 315 struct mmu_notifier_mm *mmu_notifier_mm; 316#endif 317#ifdef CONFIG_TRANSPARENT_HUGEPAGE 318 pgtable_t pmd_huge_pte; /* protected by page_table_lock */ 319#endif 320}; 321 322/* Future-safe accessor for struct mm_struct's cpu_vm_mask. */ 323#define mm_cpumask(mm) (&(mm)->cpu_vm_mask) 324 325#endif /* _LINUX_MM_TYPES_H */ 326