1 #ifndef _LINUX_MM_TYPES_H 2 #define _LINUX_MM_TYPES_H 3 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> 13 #include <asm/page.h> 14 #include <asm/mmu.h> 15 16 struct address_space; 17 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 */ 23 24 /* 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 29 * who is mapping it. 30 */ 31 struct page { 32 unsigned long flags; /* Atomic flags, some possibly 33 * updated asynchronously */ 34 atomic_t _count; /* Usage count, see below. */ 35 union { 36 atomic_t _mapcount; /* Count of ptes mapped in mms, 37 * to show when page is mapped 38 * & limit reverse map searches. 39 */ 40 unsigned int inuse; /* SLUB: Nr of objects */ 41 }; 42 union { 43 struct { 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. 50 */ 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. 57 */ 58 }; 59 #if NR_CPUS >= CONFIG_SPLIT_PTLOCK_CPUS 60 spinlock_t ptl; 61 #endif 62 struct kmem_cache *slab; /* SLUB: Pointer to slab */ 63 struct page *first_page; /* Compound tail pages */ 64 }; 65 union { 66 pgoff_t index; /* Our offset within mapping. */ 67 void *freelist; /* SLUB: freelist req. slab lock */ 68 }; 69 struct list_head lru; /* Pageout list, eg. active_list 70 * protected by zone->lru_lock ! 71 */ 72 /* 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 ... ;) 78 * 79 * Architectures with slow multiplication can define 80 * WANT_PAGE_VIRTUAL in asm/page.h 81 */ 82 #if defined(WANT_PAGE_VIRTUAL) 83 void *virtual; /* Kernel virtual address (NULL if 84 not kmapped, ie. highmem) */ 85 #endif /* WANT_PAGE_VIRTUAL */ 86 }; 87 88 /* 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). 93 */ 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 98 within vm_mm. */ 99 100 /* linked list of VM areas per task, sorted by address */ 101 struct vm_area_struct *vm_next; 102 103 pgprot_t vm_page_prot; /* Access permissions of this VMA. */ 104 unsigned long vm_flags; /* Flags, listed below. */ 105 106 struct rb_node vm_rb; 107 108 /* 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. 113 */ 114 union { 115 struct { 116 struct list_head list; 117 void *parent; /* aligns with prio_tree_node parent */ 118 struct vm_area_struct *head; 119 } vm_set; 120 121 struct raw_prio_tree_node prio_tree_node; 122 } shared; 123 124 /* 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. 129 */ 130 struct list_head anon_vma_node; /* Serialized by anon_vma->lock */ 131 struct anon_vma *anon_vma; /* Serialized by page_table_lock */ 132 133 /* Function pointers to deal with this struct. */ 134 struct vm_operations_struct * vm_ops; 135 136 /* 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 */ 142 143 #ifndef CONFIG_MMU 144 atomic_t vm_usage; /* refcount (VMAs shared if !MMU) */ 145 #endif 146 #ifdef CONFIG_NUMA 147 struct mempolicy *vm_policy; /* NUMA policy for the VMA */ 148 #endif 149 }; 150 151 struct mm_struct { 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 */ 163 pgd_t * pgd; 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 */ 169 170 struct list_head mmlist; /* List of maybe swapped mm's. These are globally strung 171 * together off init_mm.mmlist, and are protected 172 * by mmlist_lock 173 */ 174 175 /* Special counters, in some configurations protected by the 176 * page_table_lock, in other configurations by being atomic. 177 */ 178 mm_counter_t _file_rss; 179 mm_counter_t _anon_rss; 180 181 unsigned long hiwater_rss; /* High-watermark of RSS usage */ 182 unsigned long hiwater_vm; /* High-water virtual memory usage */ 183 184 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; 189 190 unsigned long saved_auxv[AT_VECTOR_SIZE]; /* for /proc/PID/auxv */ 191 192 cpumask_t cpu_vm_mask; 193 194 /* Architecture-specific MM context */ 195 mm_context_t context; 196 197 /* Swap token stuff */ 198 /* 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 203 */ 204 unsigned int faultstamp; 205 unsigned int token_priority; 206 unsigned int last_interval; 207 208 unsigned long flags; /* Must use atomic bitops to access the bits */ 209 210 /* coredumping support */ 211 int core_waiters; 212 struct completion *core_startup_done, core_done; 213 214 /* aio bits */ 215 rwlock_t ioctx_list_lock; 216 struct kioctx *ioctx_list; 217 }; 218 219 #endif /* _LINUX_MM_TYPES_H */ 220