#ifndef _LINUX_MM_TYPES_H #define _LINUX_MM_TYPES_H #include <linux/auxvec.h> #include <linux/types.h> #include <linux/threads.h> #include <linux/list.h> #include <linux/spinlock.h> #include <linux/prio_tree.h> #include <linux/rbtree.h> #include <linux/rwsem.h> #include <linux/completion.h> #include <linux/cpumask.h> #include <linux/page-debug-flags.h> #include <asm/page.h> #include <asm/mmu.h> #ifndef AT_VECTOR_SIZE_ARCH #define AT_VECTOR_SIZE_ARCH 0 #endif #define AT_VECTOR_SIZE (2*(AT_VECTOR_SIZE_ARCH + AT_VECTOR_SIZE_BASE + 1)) struct address_space; #define USE_SPLIT_PTLOCKS (NR_CPUS >= CONFIG_SPLIT_PTLOCK_CPUS) /* * Each physical page in the system has a struct page associated with * it to keep track of whatever it is we are using the page for at the * moment. Note that we have no way to track which tasks are using * a page, though if it is a pagecache page, rmap structures can tell us * who is mapping it. * * The objects in struct page are organized in double word blocks in * order to allows us to use atomic double word operations on portions * of struct page. That is currently only used by slub but the arrangement * allows the use of atomic double word operations on the flags/mapping * and lru list pointers also. */ struct page { /* First double word block */ unsigned long flags; /* Atomic flags, some possibly * updated asynchronously */ struct address_space *mapping; /* If low bit clear, points to * inode address_space, or NULL. * If page mapped as anonymous * memory, low bit is set, and * it points to anon_vma object: * see PAGE_MAPPING_ANON below. */ /* Second double word */ struct { union { pgoff_t index; /* Our offset within mapping. */ void *freelist; /* slub first free object */ }; union { /* Used for cmpxchg_double in slub */ unsigned long counters; struct { union { /* * Count of ptes mapped in * mms, to show when page is * mapped & limit reverse map * searches. * * Used also for tail pages * refcounting instead of * _count. Tail pages cannot * be mapped and keeping the * tail page _count zero at * all times guarantees * get_page_unless_zero() will * never succeed on tail * pages. */ atomic_t _mapcount; struct { unsigned inuse:16; unsigned objects:15; unsigned frozen:1; }; }; atomic_t _count; /* Usage count, see below. */ }; }; }; /* Third double word block */ union { struct list_head lru; /* Pageout list, eg. active_list * protected by zone->lru_lock ! */ struct { /* slub per cpu partial pages */ struct page *next; /* Next partial slab */ #ifdef CONFIG_64BIT int pages; /* Nr of partial slabs left */ int pobjects; /* Approximate # of objects */ #else short int pages; short int pobjects; #endif }; }; /* Remainder is not double word aligned */ union { unsigned long private; /* Mapping-private opaque data: * usually used for buffer_heads * if PagePrivate set; used for * swp_entry_t if PageSwapCache; * indicates order in the buddy * system if PG_buddy is set. */ #if USE_SPLIT_PTLOCKS spinlock_t ptl; #endif struct kmem_cache *slab; /* SLUB: Pointer to slab */ struct page *first_page; /* Compound tail pages */ }; /* * On machines where all RAM is mapped into kernel address space, * we can simply calculate the virtual address. On machines with * highmem some memory is mapped into kernel virtual memory * dynamically, so we need a place to store that address. * Note that this field could be 16 bits on x86 ... ;) * * Architectures with slow multiplication can define * WANT_PAGE_VIRTUAL in asm/page.h */ #if defined(WANT_PAGE_VIRTUAL) void *virtual; /* Kernel virtual address (NULL if not kmapped, ie. highmem) */ #endif /* WANT_PAGE_VIRTUAL */ #ifdef CONFIG_WANT_PAGE_DEBUG_FLAGS unsigned long debug_flags; /* Use atomic bitops on this */ #endif #ifdef CONFIG_KMEMCHECK /* * kmemcheck wants to track the status of each byte in a page; this * is a pointer to such a status block. NULL if not tracked. */ void *shadow; #endif } /* * The struct page can be forced to be double word aligned so that atomic ops * on double words work. The SLUB allocator can make use of such a feature. */ #ifdef CONFIG_HAVE_ALIGNED_STRUCT_PAGE __aligned(2 * sizeof(unsigned long)) #endif ; struct page_frag { struct page *page; #if (BITS_PER_LONG > 32) || (PAGE_SIZE >= 65536) __u32 offset; __u32 size; #else __u16 offset; __u16 size; #endif }; typedef unsigned long __nocast vm_flags_t; /* * A region containing a mapping of a non-memory backed file under NOMMU * conditions. These are held in a global tree and are pinned by the VMAs that * map parts of them. */ struct vm_region { struct rb_node vm_rb; /* link in global region tree */ vm_flags_t vm_flags; /* VMA vm_flags */ unsigned long vm_start; /* start address of region */ unsigned long vm_end; /* region initialised to here */ unsigned long vm_top; /* region allocated to here */ unsigned long vm_pgoff; /* the offset in vm_file corresponding to vm_start */ struct file *vm_file; /* the backing file or NULL */ int vm_usage; /* region usage count (access under nommu_region_sem) */ bool vm_icache_flushed : 1; /* true if the icache has been flushed for * this region */ }; /* * This struct defines a memory VMM memory area. There is one of these * per VM-area/task. A VM area is any part of the process virtual memory * space that has a special rule for the page-fault handlers (ie a shared * library, the executable area etc). */ struct vm_area_struct { struct mm_struct * vm_mm; /* The address space we belong to. */ unsigned long vm_start; /* Our start address within vm_mm. */ unsigned long vm_end; /* The first byte after our end address within vm_mm. */ /* linked list of VM areas per task, sorted by address */ struct vm_area_struct *vm_next, *vm_prev; pgprot_t vm_page_prot; /* Access permissions of this VMA. */ unsigned long vm_flags; /* Flags, see mm.h. */ struct rb_node vm_rb; /* * For areas with an address space and backing store, * linkage into the address_space->i_mmap prio tree, or * linkage to the list of like vmas hanging off its node, or * linkage of vma in the address_space->i_mmap_nonlinear list. */ union { struct { struct list_head list; void *parent; /* aligns with prio_tree_node parent */ struct vm_area_struct *head; } vm_set; struct raw_prio_tree_node prio_tree_node; } shared; /* * A file's MAP_PRIVATE vma can be in both i_mmap tree and anon_vma * list, after a COW of one of the file pages. A MAP_SHARED vma * can only be in the i_mmap tree. An anonymous MAP_PRIVATE, stack * or brk vma (with NULL file) can only be in an anon_vma list. */ struct list_head anon_vma_chain; /* Serialized by mmap_sem & * page_table_lock */ struct anon_vma *anon_vma; /* Serialized by page_table_lock */ /* Function pointers to deal with this struct. */ const struct vm_operations_struct *vm_ops; /* Information about our backing store: */ unsigned long vm_pgoff; /* Offset (within vm_file) in PAGE_SIZE units, *not* PAGE_CACHE_SIZE */ struct file * vm_file; /* File we map to (can be NULL). */ void * vm_private_data; /* was vm_pte (shared mem) */ #ifndef CONFIG_MMU struct vm_region *vm_region; /* NOMMU mapping region */ #endif #ifdef CONFIG_NUMA struct mempolicy *vm_policy; /* NUMA policy for the VMA */ #endif }; struct core_thread { struct task_struct *task; struct core_thread *next; }; struct core_state { atomic_t nr_threads; struct core_thread dumper; struct completion startup; }; enum { MM_FILEPAGES, MM_ANONPAGES, MM_SWAPENTS, NR_MM_COUNTERS }; #if USE_SPLIT_PTLOCKS && defined(CONFIG_MMU) #define SPLIT_RSS_COUNTING /* per-thread cached information, */ struct task_rss_stat { int events; /* for synchronization threshold */ int count[NR_MM_COUNTERS]; }; #endif /* USE_SPLIT_PTLOCKS */ struct mm_rss_stat { atomic_long_t count[NR_MM_COUNTERS]; }; struct mm_struct { struct vm_area_struct * mmap; /* list of VMAs */ struct rb_root mm_rb; struct vm_area_struct * mmap_cache; /* last find_vma result */ #ifdef CONFIG_MMU unsigned long (*get_unmapped_area) (struct file *filp, unsigned long addr, unsigned long len, unsigned long pgoff, unsigned long flags); void (*unmap_area) (struct mm_struct *mm, unsigned long addr); #endif unsigned long mmap_base; /* base of mmap area */ unsigned long task_size; /* size of task vm space */ unsigned long cached_hole_size; /* if non-zero, the largest hole below free_area_cache */ unsigned long free_area_cache; /* first hole of size cached_hole_size or larger */ pgd_t * pgd; atomic_t mm_users; /* How many users with user space? */ atomic_t mm_count; /* How many references to "struct mm_struct" (users count as 1) */ int map_count; /* number of VMAs */ spinlock_t page_table_lock; /* Protects page tables and some counters */ struct rw_semaphore mmap_sem; struct list_head mmlist; /* List of maybe swapped mm's. These are globally strung * together off init_mm.mmlist, and are protected * by mmlist_lock */ unsigned long hiwater_rss; /* High-watermark of RSS usage */ unsigned long hiwater_vm; /* High-water virtual memory usage */ unsigned long total_vm; /* Total pages mapped */ unsigned long locked_vm; /* Pages that have PG_mlocked set */ unsigned long pinned_vm; /* Refcount permanently increased */ unsigned long shared_vm; /* Shared pages (files) */ unsigned long exec_vm; /* VM_EXEC & ~VM_WRITE */ unsigned long stack_vm; /* VM_GROWSUP/DOWN */ unsigned long reserved_vm; /* VM_RESERVED|VM_IO pages */ unsigned long def_flags; unsigned long nr_ptes; /* Page table pages */ unsigned long start_code, end_code, start_data, end_data; unsigned long start_brk, brk, start_stack; unsigned long arg_start, arg_end, env_start, env_end; unsigned long saved_auxv[AT_VECTOR_SIZE]; /* for /proc/PID/auxv */ /* * Special counters, in some configurations protected by the * page_table_lock, in other configurations by being atomic. */ struct mm_rss_stat rss_stat; struct linux_binfmt *binfmt; cpumask_var_t cpu_vm_mask_var; /* Architecture-specific MM context */ mm_context_t context; /* Swap token stuff */ /* * Last value of global fault stamp as seen by this process. * In other words, this value gives an indication of how long * it has been since this task got the token. * Look at mm/thrash.c */ unsigned int faultstamp; unsigned int token_priority; unsigned int last_interval; unsigned long flags; /* Must use atomic bitops to access the bits */ struct core_state *core_state; /* coredumping support */ #ifdef CONFIG_AIO spinlock_t ioctx_lock; struct hlist_head ioctx_list; #endif #ifdef CONFIG_MM_OWNER /* * "owner" points to a task that is regarded as the canonical * user/owner of this mm. All of the following must be true in * order for it to be changed: * * current == mm->owner * current->mm != mm * new_owner->mm == mm * new_owner->alloc_lock is held */ struct task_struct __rcu *owner; #endif /* store ref to file /proc/<pid>/exe symlink points to */ struct file *exe_file; unsigned long num_exe_file_vmas; #ifdef CONFIG_MMU_NOTIFIER struct mmu_notifier_mm *mmu_notifier_mm; #endif #ifdef CONFIG_TRANSPARENT_HUGEPAGE pgtable_t pmd_huge_pte; /* protected by page_table_lock */ #endif #ifdef CONFIG_CPUMASK_OFFSTACK struct cpumask cpumask_allocation; #endif }; static inline void mm_init_cpumask(struct mm_struct *mm) { #ifdef CONFIG_CPUMASK_OFFSTACK mm->cpu_vm_mask_var = &mm->cpumask_allocation; #endif } /* Future-safe accessor for struct mm_struct's cpu_vm_mask. */ static inline cpumask_t *mm_cpumask(struct mm_struct *mm) { return mm->cpu_vm_mask_var; } #endif /* _LINUX_MM_TYPES_H */