| #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/rbtree.h> |
| #include <linux/rwsem.h> |
| #include <linux/completion.h> |
| #include <linux/cpumask.h> |
| #include <linux/uprobes.h> |
| #include <linux/page-flags-layout.h> |
| #include <linux/workqueue.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; |
| struct mem_cgroup; |
| |
| #define USE_SPLIT_PTE_PTLOCKS (NR_CPUS >= CONFIG_SPLIT_PTLOCK_CPUS) |
| #define USE_SPLIT_PMD_PTLOCKS (USE_SPLIT_PTE_PTLOCKS && \ |
| IS_ENABLED(CONFIG_ARCH_ENABLE_SPLIT_PMD_PTLOCK)) |
| #define ALLOC_SPLIT_PTLOCKS (SPINLOCK_SIZE > BITS_PER_LONG/8) |
| |
| /* |
| * 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 */ |
| union { |
| 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. |
| */ |
| void *s_mem; /* slab first object */ |
| atomic_t compound_mapcount; /* first tail page */ |
| /* page_deferred_list().next -- second tail page */ |
| }; |
| |
| /* Second double word */ |
| struct { |
| union { |
| pgoff_t index; /* Our offset within mapping. */ |
| void *freelist; /* sl[aou]b first free object */ |
| /* page_deferred_list().prev -- second tail page */ |
| }; |
| |
| union { |
| #if defined(CONFIG_HAVE_CMPXCHG_DOUBLE) && \ |
| defined(CONFIG_HAVE_ALIGNED_STRUCT_PAGE) |
| /* Used for cmpxchg_double in slub */ |
| unsigned long counters; |
| #else |
| /* |
| * Keep _refcount separate from slub cmpxchg_double |
| * data. As the rest of the double word is protected by |
| * slab_lock but _refcount is not. |
| */ |
| unsigned counters; |
| #endif |
| |
| struct { |
| |
| union { |
| /* |
| * Count of ptes mapped in mms, to show |
| * when page is mapped & limit reverse |
| * map searches. |
| */ |
| atomic_t _mapcount; |
| |
| struct { /* SLUB */ |
| unsigned inuse:16; |
| unsigned objects:15; |
| unsigned frozen:1; |
| }; |
| int units; /* SLOB */ |
| }; |
| /* |
| * Usage count, *USE WRAPPER FUNCTION* |
| * when manual accounting. See page_ref.h |
| */ |
| atomic_t _refcount; |
| }; |
| unsigned int active; /* SLAB */ |
| }; |
| }; |
| |
| /* |
| * Third double word block |
| * |
| * WARNING: bit 0 of the first word encode PageTail(). That means |
| * the rest users of the storage space MUST NOT use the bit to |
| * avoid collision and false-positive PageTail(). |
| */ |
| union { |
| struct list_head lru; /* Pageout list, eg. active_list |
| * protected by zone->lru_lock ! |
| * Can be used as a generic list |
| * by the page owner. |
| */ |
| struct dev_pagemap *pgmap; /* ZONE_DEVICE pages are never on an |
| * lru or handled by a slab |
| * allocator, this points to the |
| * hosting device page map. |
| */ |
| 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 |
| }; |
| |
| struct rcu_head rcu_head; /* Used by SLAB |
| * when destroying via RCU |
| */ |
| /* Tail pages of compound page */ |
| struct { |
| unsigned long compound_head; /* If bit zero is set */ |
| |
| /* First tail page only */ |
| #ifdef CONFIG_64BIT |
| /* |
| * On 64 bit system we have enough space in struct page |
| * to encode compound_dtor and compound_order with |
| * unsigned int. It can help compiler generate better or |
| * smaller code on some archtectures. |
| */ |
| unsigned int compound_dtor; |
| unsigned int compound_order; |
| #else |
| unsigned short int compound_dtor; |
| unsigned short int compound_order; |
| #endif |
| }; |
| |
| #if defined(CONFIG_TRANSPARENT_HUGEPAGE) && USE_SPLIT_PMD_PTLOCKS |
| struct { |
| unsigned long __pad; /* do not overlay pmd_huge_pte |
| * with compound_head to avoid |
| * possible bit 0 collision. |
| */ |
| pgtable_t pmd_huge_pte; /* protected by page->ptl */ |
| }; |
| #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_PTE_PTLOCKS |
| #if ALLOC_SPLIT_PTLOCKS |
| spinlock_t *ptl; |
| #else |
| spinlock_t ptl; |
| #endif |
| #endif |
| struct kmem_cache *slab_cache; /* SL[AU]B: Pointer to slab */ |
| }; |
| |
| #ifdef CONFIG_MEMCG |
| struct mem_cgroup *mem_cgroup; |
| #endif |
| |
| /* |
| * 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_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 |
| |
| #ifdef LAST_CPUPID_NOT_IN_PAGE_FLAGS |
| int _last_cpupid; |
| #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 |
| }; |
| |
| #define PAGE_FRAG_CACHE_MAX_SIZE __ALIGN_MASK(32768, ~PAGE_MASK) |
| #define PAGE_FRAG_CACHE_MAX_ORDER get_order(PAGE_FRAG_CACHE_MAX_SIZE) |
| |
| struct page_frag_cache { |
| void * va; |
| #if (PAGE_SIZE < PAGE_FRAG_CACHE_MAX_SIZE) |
| __u16 offset; |
| __u16 size; |
| #else |
| __u32 offset; |
| #endif |
| /* we maintain a pagecount bias, so that we dont dirty cache line |
| * containing page->_refcount every time we allocate a fragment. |
| */ |
| unsigned int pagecnt_bias; |
| bool pfmemalloc; |
| }; |
| |
| typedef unsigned long 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 */ |
| }; |
| |
| #ifdef CONFIG_USERFAULTFD |
| #define NULL_VM_UFFD_CTX ((struct vm_userfaultfd_ctx) { NULL, }) |
| struct vm_userfaultfd_ctx { |
| struct userfaultfd_ctx *ctx; |
| }; |
| #else /* CONFIG_USERFAULTFD */ |
| #define NULL_VM_UFFD_CTX ((struct vm_userfaultfd_ctx) {}) |
| struct vm_userfaultfd_ctx {}; |
| #endif /* CONFIG_USERFAULTFD */ |
| |
| /* |
| * 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 { |
| /* The first cache line has the info for VMA tree walking. */ |
| |
| 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; |
| |
| struct rb_node vm_rb; |
| |
| /* |
| * Largest free memory gap in bytes to the left of this VMA. |
| * Either between this VMA and vma->vm_prev, or between one of the |
| * VMAs below us in the VMA rbtree and its ->vm_prev. This helps |
| * get_unmapped_area find a free area of the right size. |
| */ |
| unsigned long rb_subtree_gap; |
| |
| /* Second cache line starts here. */ |
| |
| struct mm_struct *vm_mm; /* The address space we belong to. */ |
| pgprot_t vm_page_prot; /* Access permissions of this VMA. */ |
| unsigned long vm_flags; /* Flags, see mm.h. */ |
| |
| /* |
| * For areas with an address space and backing store, |
| * linkage into the address_space->i_mmap interval tree. |
| */ |
| struct { |
| struct rb_node rb; |
| unsigned long rb_subtree_last; |
| } 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 */ |
| 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 vm_userfaultfd_ctx vm_userfaultfd_ctx; |
| }; |
| |
| 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, /* Resident file mapping pages */ |
| MM_ANONPAGES, /* Resident anonymous pages */ |
| MM_SWAPENTS, /* Anonymous swap entries */ |
| MM_SHMEMPAGES, /* Resident shared memory pages */ |
| NR_MM_COUNTERS |
| }; |
| |
| #if USE_SPLIT_PTE_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_PTE_PTLOCKS */ |
| |
| struct mm_rss_stat { |
| atomic_long_t count[NR_MM_COUNTERS]; |
| }; |
| |
| struct kioctx_table; |
| struct mm_struct { |
| struct vm_area_struct *mmap; /* list of VMAs */ |
| struct rb_root mm_rb; |
| u32 vmacache_seqnum; /* per-thread vmacache */ |
| #ifdef CONFIG_MMU |
| unsigned long (*get_unmapped_area) (struct file *filp, |
| unsigned long addr, unsigned long len, |
| unsigned long pgoff, unsigned long flags); |
| #endif |
| unsigned long mmap_base; /* base of mmap area */ |
| unsigned long mmap_legacy_base; /* base of mmap area in bottom-up allocations */ |
| unsigned long task_size; /* size of task vm space */ |
| unsigned long highest_vm_end; /* highest vma end address */ |
| 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) */ |
| atomic_long_t nr_ptes; /* PTE page table pages */ |
| #if CONFIG_PGTABLE_LEVELS > 2 |
| atomic_long_t nr_pmds; /* PMD page table pages */ |
| #endif |
| 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 data_vm; /* VM_WRITE & ~VM_SHARED & ~VM_STACK */ |
| unsigned long exec_vm; /* VM_EXEC & ~VM_WRITE & ~VM_STACK */ |
| unsigned long stack_vm; /* VM_STACK */ |
| unsigned long def_flags; |
| 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; |
| |
| 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 kioctx_table __rcu *ioctx_table; |
| #endif |
| #ifdef CONFIG_MEMCG |
| /* |
| * "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 __rcu *exe_file; |
| #ifdef CONFIG_MMU_NOTIFIER |
| struct mmu_notifier_mm *mmu_notifier_mm; |
| #endif |
| #if defined(CONFIG_TRANSPARENT_HUGEPAGE) && !USE_SPLIT_PMD_PTLOCKS |
| pgtable_t pmd_huge_pte; /* protected by page_table_lock */ |
| #endif |
| #ifdef CONFIG_CPUMASK_OFFSTACK |
| struct cpumask cpumask_allocation; |
| #endif |
| #ifdef CONFIG_NUMA_BALANCING |
| /* |
| * numa_next_scan is the next time that the PTEs will be marked |
| * pte_numa. NUMA hinting faults will gather statistics and migrate |
| * pages to new nodes if necessary. |
| */ |
| unsigned long numa_next_scan; |
| |
| /* Restart point for scanning and setting pte_numa */ |
| unsigned long numa_scan_offset; |
| |
| /* numa_scan_seq prevents two threads setting pte_numa */ |
| int numa_scan_seq; |
| #endif |
| #if defined(CONFIG_NUMA_BALANCING) || defined(CONFIG_COMPACTION) |
| /* |
| * An operation with batched TLB flushing is going on. Anything that |
| * can move process memory needs to flush the TLB when moving a |
| * PROT_NONE or PROT_NUMA mapped page. |
| */ |
| bool tlb_flush_pending; |
| #endif |
| struct uprobes_state uprobes_state; |
| #ifdef CONFIG_X86_INTEL_MPX |
| /* address of the bounds directory */ |
| void __user *bd_addr; |
| #endif |
| #ifdef CONFIG_HUGETLB_PAGE |
| atomic_long_t hugetlb_usage; |
| #endif |
| #ifdef CONFIG_MMU |
| struct work_struct async_put_work; |
| #endif |
| }; |
| |
| static inline void mm_init_cpumask(struct mm_struct *mm) |
| { |
| #ifdef CONFIG_CPUMASK_OFFSTACK |
| mm->cpu_vm_mask_var = &mm->cpumask_allocation; |
| #endif |
| cpumask_clear(mm->cpu_vm_mask_var); |
| } |
| |
| /* 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; |
| } |
| |
| #if defined(CONFIG_NUMA_BALANCING) || defined(CONFIG_COMPACTION) |
| /* |
| * Memory barriers to keep this state in sync are graciously provided by |
| * the page table locks, outside of which no page table modifications happen. |
| * The barriers below prevent the compiler from re-ordering the instructions |
| * around the memory barriers that are already present in the code. |
| */ |
| static inline bool mm_tlb_flush_pending(struct mm_struct *mm) |
| { |
| barrier(); |
| return mm->tlb_flush_pending; |
| } |
| static inline void set_tlb_flush_pending(struct mm_struct *mm) |
| { |
| mm->tlb_flush_pending = true; |
| |
| /* |
| * Guarantee that the tlb_flush_pending store does not leak into the |
| * critical section updating the page tables |
| */ |
| smp_mb__before_spinlock(); |
| } |
| /* Clearing is done after a TLB flush, which also provides a barrier. */ |
| static inline void clear_tlb_flush_pending(struct mm_struct *mm) |
| { |
| barrier(); |
| mm->tlb_flush_pending = false; |
| } |
| #else |
| static inline bool mm_tlb_flush_pending(struct mm_struct *mm) |
| { |
| return false; |
| } |
| static inline void set_tlb_flush_pending(struct mm_struct *mm) |
| { |
| } |
| static inline void clear_tlb_flush_pending(struct mm_struct *mm) |
| { |
| } |
| #endif |
| |
| struct vm_fault; |
| |
| struct vm_special_mapping { |
| const char *name; /* The name, e.g. "[vdso]". */ |
| |
| /* |
| * If .fault is not provided, this points to a |
| * NULL-terminated array of pages that back the special mapping. |
| * |
| * This must not be NULL unless .fault is provided. |
| */ |
| struct page **pages; |
| |
| /* |
| * If non-NULL, then this is called to resolve page faults |
| * on the special mapping. If used, .pages is not checked. |
| */ |
| int (*fault)(const struct vm_special_mapping *sm, |
| struct vm_area_struct *vma, |
| struct vm_fault *vmf); |
| }; |
| |
| enum tlb_flush_reason { |
| TLB_FLUSH_ON_TASK_SWITCH, |
| TLB_REMOTE_SHOOTDOWN, |
| TLB_LOCAL_SHOOTDOWN, |
| TLB_LOCAL_MM_SHOOTDOWN, |
| TLB_REMOTE_SEND_IPI, |
| NR_TLB_FLUSH_REASONS, |
| }; |
| |
| /* |
| * A swap entry has to fit into a "unsigned long", as the entry is hidden |
| * in the "index" field of the swapper address space. |
| */ |
| typedef struct { |
| unsigned long val; |
| } swp_entry_t; |
| |
| #endif /* _LINUX_MM_TYPES_H */ |