1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _LINUX_MM_TYPES_H 3 #define _LINUX_MM_TYPES_H 4 5 #include <linux/mm_types_task.h> 6 7 #include <linux/auxvec.h> 8 #include <linux/list.h> 9 #include <linux/spinlock.h> 10 #include <linux/rbtree.h> 11 #include <linux/rwsem.h> 12 #include <linux/completion.h> 13 #include <linux/cpumask.h> 14 #include <linux/uprobes.h> 15 #include <linux/page-flags-layout.h> 16 #include <linux/workqueue.h> 17 18 #include <asm/mmu.h> 19 20 #ifndef AT_VECTOR_SIZE_ARCH 21 #define AT_VECTOR_SIZE_ARCH 0 22 #endif 23 #define AT_VECTOR_SIZE (2*(AT_VECTOR_SIZE_ARCH + AT_VECTOR_SIZE_BASE + 1)) 24 25 26 struct address_space; 27 struct mem_cgroup; 28 29 /* 30 * Each physical page in the system has a struct page associated with 31 * it to keep track of whatever it is we are using the page for at the 32 * moment. Note that we have no way to track which tasks are using 33 * a page, though if it is a pagecache page, rmap structures can tell us 34 * who is mapping it. 35 * 36 * If you allocate the page using alloc_pages(), you can use some of the 37 * space in struct page for your own purposes. The five words in the main 38 * union are available, except for bit 0 of the first word which must be 39 * kept clear. Many users use this word to store a pointer to an object 40 * which is guaranteed to be aligned. If you use the same storage as 41 * page->mapping, you must restore it to NULL before freeing the page. 42 * 43 * If your page will not be mapped to userspace, you can also use the four 44 * bytes in the mapcount union, but you must call page_mapcount_reset() 45 * before freeing it. 46 * 47 * If you want to use the refcount field, it must be used in such a way 48 * that other CPUs temporarily incrementing and then decrementing the 49 * refcount does not cause problems. On receiving the page from 50 * alloc_pages(), the refcount will be positive. 51 * 52 * If you allocate pages of order > 0, you can use some of the fields 53 * in each subpage, but you may need to restore some of their values 54 * afterwards. 55 * 56 * SLUB uses cmpxchg_double() to atomically update its freelist and 57 * counters. That requires that freelist & counters be adjacent and 58 * double-word aligned. We align all struct pages to double-word 59 * boundaries, and ensure that 'freelist' is aligned within the 60 * struct. 61 */ 62 #ifdef CONFIG_HAVE_ALIGNED_STRUCT_PAGE 63 #define _struct_page_alignment __aligned(2 * sizeof(unsigned long)) 64 #else 65 #define _struct_page_alignment 66 #endif 67 68 struct page { 69 unsigned long flags; /* Atomic flags, some possibly 70 * updated asynchronously */ 71 /* 72 * Five words (20/40 bytes) are available in this union. 73 * WARNING: bit 0 of the first word is used for PageTail(). That 74 * means the other users of this union MUST NOT use the bit to 75 * avoid collision and false-positive PageTail(). 76 */ 77 union { 78 struct { /* Page cache and anonymous pages */ 79 /** 80 * @lru: Pageout list, eg. active_list protected by 81 * pgdat->lru_lock. Sometimes used as a generic list 82 * by the page owner. 83 */ 84 struct list_head lru; 85 /* See page-flags.h for PAGE_MAPPING_FLAGS */ 86 struct address_space *mapping; 87 pgoff_t index; /* Our offset within mapping. */ 88 /** 89 * @private: Mapping-private opaque data. 90 * Usually used for buffer_heads if PagePrivate. 91 * Used for swp_entry_t if PageSwapCache. 92 * Indicates order in the buddy system if PageBuddy. 93 */ 94 unsigned long private; 95 }; 96 struct { /* page_pool used by netstack */ 97 /** 98 * @dma_addr: might require a 64-bit value even on 99 * 32-bit architectures. 100 */ 101 dma_addr_t dma_addr; 102 }; 103 struct { /* slab, slob and slub */ 104 union { 105 struct list_head slab_list; 106 struct { /* Partial pages */ 107 struct page *next; 108 #ifdef CONFIG_64BIT 109 int pages; /* Nr of pages left */ 110 int pobjects; /* Approximate count */ 111 #else 112 short int pages; 113 short int pobjects; 114 #endif 115 }; 116 }; 117 struct kmem_cache *slab_cache; /* not slob */ 118 /* Double-word boundary */ 119 void *freelist; /* first free object */ 120 union { 121 void *s_mem; /* slab: first object */ 122 unsigned long counters; /* SLUB */ 123 struct { /* SLUB */ 124 unsigned inuse:16; 125 unsigned objects:15; 126 unsigned frozen:1; 127 }; 128 }; 129 }; 130 struct { /* Tail pages of compound page */ 131 unsigned long compound_head; /* Bit zero is set */ 132 133 /* First tail page only */ 134 unsigned char compound_dtor; 135 unsigned char compound_order; 136 atomic_t compound_mapcount; 137 }; 138 struct { /* Second tail page of compound page */ 139 unsigned long _compound_pad_1; /* compound_head */ 140 unsigned long _compound_pad_2; 141 /* For both global and memcg */ 142 struct list_head deferred_list; 143 }; 144 struct { /* Page table pages */ 145 unsigned long _pt_pad_1; /* compound_head */ 146 pgtable_t pmd_huge_pte; /* protected by page->ptl */ 147 unsigned long _pt_pad_2; /* mapping */ 148 union { 149 struct mm_struct *pt_mm; /* x86 pgds only */ 150 atomic_t pt_frag_refcount; /* powerpc */ 151 }; 152 #if ALLOC_SPLIT_PTLOCKS 153 spinlock_t *ptl; 154 #else 155 spinlock_t ptl; 156 #endif 157 }; 158 struct { /* ZONE_DEVICE pages */ 159 /** @pgmap: Points to the hosting device page map. */ 160 struct dev_pagemap *pgmap; 161 void *zone_device_data; 162 /* 163 * ZONE_DEVICE private pages are counted as being 164 * mapped so the next 3 words hold the mapping, index, 165 * and private fields from the source anonymous or 166 * page cache page while the page is migrated to device 167 * private memory. 168 * ZONE_DEVICE MEMORY_DEVICE_FS_DAX pages also 169 * use the mapping, index, and private fields when 170 * pmem backed DAX files are mapped. 171 */ 172 }; 173 174 /** @rcu_head: You can use this to free a page by RCU. */ 175 struct rcu_head rcu_head; 176 }; 177 178 union { /* This union is 4 bytes in size. */ 179 /* 180 * If the page can be mapped to userspace, encodes the number 181 * of times this page is referenced by a page table. 182 */ 183 atomic_t _mapcount; 184 185 /* 186 * If the page is neither PageSlab nor mappable to userspace, 187 * the value stored here may help determine what this page 188 * is used for. See page-flags.h for a list of page types 189 * which are currently stored here. 190 */ 191 unsigned int page_type; 192 193 unsigned int active; /* SLAB */ 194 int units; /* SLOB */ 195 }; 196 197 /* Usage count. *DO NOT USE DIRECTLY*. See page_ref.h */ 198 atomic_t _refcount; 199 200 #ifdef CONFIG_MEMCG 201 struct mem_cgroup *mem_cgroup; 202 #endif 203 204 /* 205 * On machines where all RAM is mapped into kernel address space, 206 * we can simply calculate the virtual address. On machines with 207 * highmem some memory is mapped into kernel virtual memory 208 * dynamically, so we need a place to store that address. 209 * Note that this field could be 16 bits on x86 ... ;) 210 * 211 * Architectures with slow multiplication can define 212 * WANT_PAGE_VIRTUAL in asm/page.h 213 */ 214 #if defined(WANT_PAGE_VIRTUAL) 215 void *virtual; /* Kernel virtual address (NULL if 216 not kmapped, ie. highmem) */ 217 #endif /* WANT_PAGE_VIRTUAL */ 218 219 #ifdef LAST_CPUPID_NOT_IN_PAGE_FLAGS 220 int _last_cpupid; 221 #endif 222 } _struct_page_alignment; 223 224 /* 225 * Used for sizing the vmemmap region on some architectures 226 */ 227 #define STRUCT_PAGE_MAX_SHIFT (order_base_2(sizeof(struct page))) 228 229 #define PAGE_FRAG_CACHE_MAX_SIZE __ALIGN_MASK(32768, ~PAGE_MASK) 230 #define PAGE_FRAG_CACHE_MAX_ORDER get_order(PAGE_FRAG_CACHE_MAX_SIZE) 231 232 #define page_private(page) ((page)->private) 233 #define set_page_private(page, v) ((page)->private = (v)) 234 235 struct page_frag_cache { 236 void * va; 237 #if (PAGE_SIZE < PAGE_FRAG_CACHE_MAX_SIZE) 238 __u16 offset; 239 __u16 size; 240 #else 241 __u32 offset; 242 #endif 243 /* we maintain a pagecount bias, so that we dont dirty cache line 244 * containing page->_refcount every time we allocate a fragment. 245 */ 246 unsigned int pagecnt_bias; 247 bool pfmemalloc; 248 }; 249 250 typedef unsigned long vm_flags_t; 251 252 /* 253 * A region containing a mapping of a non-memory backed file under NOMMU 254 * conditions. These are held in a global tree and are pinned by the VMAs that 255 * map parts of them. 256 */ 257 struct vm_region { 258 struct rb_node vm_rb; /* link in global region tree */ 259 vm_flags_t vm_flags; /* VMA vm_flags */ 260 unsigned long vm_start; /* start address of region */ 261 unsigned long vm_end; /* region initialised to here */ 262 unsigned long vm_top; /* region allocated to here */ 263 unsigned long vm_pgoff; /* the offset in vm_file corresponding to vm_start */ 264 struct file *vm_file; /* the backing file or NULL */ 265 266 int vm_usage; /* region usage count (access under nommu_region_sem) */ 267 bool vm_icache_flushed : 1; /* true if the icache has been flushed for 268 * this region */ 269 }; 270 271 #ifdef CONFIG_USERFAULTFD 272 #define NULL_VM_UFFD_CTX ((struct vm_userfaultfd_ctx) { NULL, }) 273 struct vm_userfaultfd_ctx { 274 struct userfaultfd_ctx *ctx; 275 }; 276 #else /* CONFIG_USERFAULTFD */ 277 #define NULL_VM_UFFD_CTX ((struct vm_userfaultfd_ctx) {}) 278 struct vm_userfaultfd_ctx {}; 279 #endif /* CONFIG_USERFAULTFD */ 280 281 /* 282 * This struct defines a memory VMM memory area. There is one of these 283 * per VM-area/task. A VM area is any part of the process virtual memory 284 * space that has a special rule for the page-fault handlers (ie a shared 285 * library, the executable area etc). 286 */ 287 struct vm_area_struct { 288 /* The first cache line has the info for VMA tree walking. */ 289 290 unsigned long vm_start; /* Our start address within vm_mm. */ 291 unsigned long vm_end; /* The first byte after our end address 292 within vm_mm. */ 293 294 /* linked list of VM areas per task, sorted by address */ 295 struct vm_area_struct *vm_next, *vm_prev; 296 297 struct rb_node vm_rb; 298 299 /* 300 * Largest free memory gap in bytes to the left of this VMA. 301 * Either between this VMA and vma->vm_prev, or between one of the 302 * VMAs below us in the VMA rbtree and its ->vm_prev. This helps 303 * get_unmapped_area find a free area of the right size. 304 */ 305 unsigned long rb_subtree_gap; 306 307 /* Second cache line starts here. */ 308 309 struct mm_struct *vm_mm; /* The address space we belong to. */ 310 pgprot_t vm_page_prot; /* Access permissions of this VMA. */ 311 unsigned long vm_flags; /* Flags, see mm.h. */ 312 313 /* 314 * For areas with an address space and backing store, 315 * linkage into the address_space->i_mmap interval tree. 316 */ 317 struct { 318 struct rb_node rb; 319 unsigned long rb_subtree_last; 320 } shared; 321 322 /* 323 * A file's MAP_PRIVATE vma can be in both i_mmap tree and anon_vma 324 * list, after a COW of one of the file pages. A MAP_SHARED vma 325 * can only be in the i_mmap tree. An anonymous MAP_PRIVATE, stack 326 * or brk vma (with NULL file) can only be in an anon_vma list. 327 */ 328 struct list_head anon_vma_chain; /* Serialized by mmap_sem & 329 * page_table_lock */ 330 struct anon_vma *anon_vma; /* Serialized by page_table_lock */ 331 332 /* Function pointers to deal with this struct. */ 333 const struct vm_operations_struct *vm_ops; 334 335 /* Information about our backing store: */ 336 unsigned long vm_pgoff; /* Offset (within vm_file) in PAGE_SIZE 337 units */ 338 struct file * vm_file; /* File we map to (can be NULL). */ 339 void * vm_private_data; /* was vm_pte (shared mem) */ 340 341 #ifdef CONFIG_SWAP 342 atomic_long_t swap_readahead_info; 343 #endif 344 #ifndef CONFIG_MMU 345 struct vm_region *vm_region; /* NOMMU mapping region */ 346 #endif 347 #ifdef CONFIG_NUMA 348 struct mempolicy *vm_policy; /* NUMA policy for the VMA */ 349 #endif 350 struct vm_userfaultfd_ctx vm_userfaultfd_ctx; 351 } __randomize_layout; 352 353 struct core_thread { 354 struct task_struct *task; 355 struct core_thread *next; 356 }; 357 358 struct core_state { 359 atomic_t nr_threads; 360 struct core_thread dumper; 361 struct completion startup; 362 }; 363 364 struct kioctx_table; 365 struct mm_struct { 366 struct { 367 struct vm_area_struct *mmap; /* list of VMAs */ 368 struct rb_root mm_rb; 369 u64 vmacache_seqnum; /* per-thread vmacache */ 370 #ifdef CONFIG_MMU 371 unsigned long (*get_unmapped_area) (struct file *filp, 372 unsigned long addr, unsigned long len, 373 unsigned long pgoff, unsigned long flags); 374 #endif 375 unsigned long mmap_base; /* base of mmap area */ 376 unsigned long mmap_legacy_base; /* base of mmap area in bottom-up allocations */ 377 #ifdef CONFIG_HAVE_ARCH_COMPAT_MMAP_BASES 378 /* Base adresses for compatible mmap() */ 379 unsigned long mmap_compat_base; 380 unsigned long mmap_compat_legacy_base; 381 #endif 382 unsigned long task_size; /* size of task vm space */ 383 unsigned long highest_vm_end; /* highest vma end address */ 384 pgd_t * pgd; 385 386 #ifdef CONFIG_MEMBARRIER 387 /** 388 * @membarrier_state: Flags controlling membarrier behavior. 389 * 390 * This field is close to @pgd to hopefully fit in the same 391 * cache-line, which needs to be touched by switch_mm(). 392 */ 393 atomic_t membarrier_state; 394 #endif 395 396 /** 397 * @mm_users: The number of users including userspace. 398 * 399 * Use mmget()/mmget_not_zero()/mmput() to modify. When this 400 * drops to 0 (i.e. when the task exits and there are no other 401 * temporary reference holders), we also release a reference on 402 * @mm_count (which may then free the &struct mm_struct if 403 * @mm_count also drops to 0). 404 */ 405 atomic_t mm_users; 406 407 /** 408 * @mm_count: The number of references to &struct mm_struct 409 * (@mm_users count as 1). 410 * 411 * Use mmgrab()/mmdrop() to modify. When this drops to 0, the 412 * &struct mm_struct is freed. 413 */ 414 atomic_t mm_count; 415 416 #ifdef CONFIG_MMU 417 atomic_long_t pgtables_bytes; /* PTE page table pages */ 418 #endif 419 int map_count; /* number of VMAs */ 420 421 spinlock_t page_table_lock; /* Protects page tables and some 422 * counters 423 */ 424 struct rw_semaphore mmap_sem; 425 426 struct list_head mmlist; /* List of maybe swapped mm's. These 427 * are globally strung together off 428 * init_mm.mmlist, and are protected 429 * by mmlist_lock 430 */ 431 432 433 unsigned long hiwater_rss; /* High-watermark of RSS usage */ 434 unsigned long hiwater_vm; /* High-water virtual memory usage */ 435 436 unsigned long total_vm; /* Total pages mapped */ 437 unsigned long locked_vm; /* Pages that have PG_mlocked set */ 438 atomic64_t pinned_vm; /* Refcount permanently increased */ 439 unsigned long data_vm; /* VM_WRITE & ~VM_SHARED & ~VM_STACK */ 440 unsigned long exec_vm; /* VM_EXEC & ~VM_WRITE & ~VM_STACK */ 441 unsigned long stack_vm; /* VM_STACK */ 442 unsigned long def_flags; 443 444 spinlock_t arg_lock; /* protect the below fields */ 445 unsigned long start_code, end_code, start_data, end_data; 446 unsigned long start_brk, brk, start_stack; 447 unsigned long arg_start, arg_end, env_start, env_end; 448 449 unsigned long saved_auxv[AT_VECTOR_SIZE]; /* for /proc/PID/auxv */ 450 451 /* 452 * Special counters, in some configurations protected by the 453 * page_table_lock, in other configurations by being atomic. 454 */ 455 struct mm_rss_stat rss_stat; 456 457 struct linux_binfmt *binfmt; 458 459 /* Architecture-specific MM context */ 460 mm_context_t context; 461 462 unsigned long flags; /* Must use atomic bitops to access */ 463 464 struct core_state *core_state; /* coredumping support */ 465 466 #ifdef CONFIG_AIO 467 spinlock_t ioctx_lock; 468 struct kioctx_table __rcu *ioctx_table; 469 #endif 470 #ifdef CONFIG_MEMCG 471 /* 472 * "owner" points to a task that is regarded as the canonical 473 * user/owner of this mm. All of the following must be true in 474 * order for it to be changed: 475 * 476 * current == mm->owner 477 * current->mm != mm 478 * new_owner->mm == mm 479 * new_owner->alloc_lock is held 480 */ 481 struct task_struct __rcu *owner; 482 #endif 483 struct user_namespace *user_ns; 484 485 /* store ref to file /proc/<pid>/exe symlink points to */ 486 struct file __rcu *exe_file; 487 #ifdef CONFIG_MMU_NOTIFIER 488 struct mmu_notifier_mm *mmu_notifier_mm; 489 #endif 490 #if defined(CONFIG_TRANSPARENT_HUGEPAGE) && !USE_SPLIT_PMD_PTLOCKS 491 pgtable_t pmd_huge_pte; /* protected by page_table_lock */ 492 #endif 493 #ifdef CONFIG_NUMA_BALANCING 494 /* 495 * numa_next_scan is the next time that the PTEs will be marked 496 * pte_numa. NUMA hinting faults will gather statistics and 497 * migrate pages to new nodes if necessary. 498 */ 499 unsigned long numa_next_scan; 500 501 /* Restart point for scanning and setting pte_numa */ 502 unsigned long numa_scan_offset; 503 504 /* numa_scan_seq prevents two threads setting pte_numa */ 505 int numa_scan_seq; 506 #endif 507 /* 508 * An operation with batched TLB flushing is going on. Anything 509 * that can move process memory needs to flush the TLB when 510 * moving a PROT_NONE or PROT_NUMA mapped page. 511 */ 512 atomic_t tlb_flush_pending; 513 #ifdef CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH 514 /* See flush_tlb_batched_pending() */ 515 bool tlb_flush_batched; 516 #endif 517 struct uprobes_state uprobes_state; 518 #ifdef CONFIG_HUGETLB_PAGE 519 atomic_long_t hugetlb_usage; 520 #endif 521 struct work_struct async_put_work; 522 } __randomize_layout; 523 524 /* 525 * The mm_cpumask needs to be at the end of mm_struct, because it 526 * is dynamically sized based on nr_cpu_ids. 527 */ 528 unsigned long cpu_bitmap[]; 529 }; 530 531 extern struct mm_struct init_mm; 532 533 /* Pointer magic because the dynamic array size confuses some compilers. */ 534 static inline void mm_init_cpumask(struct mm_struct *mm) 535 { 536 unsigned long cpu_bitmap = (unsigned long)mm; 537 538 cpu_bitmap += offsetof(struct mm_struct, cpu_bitmap); 539 cpumask_clear((struct cpumask *)cpu_bitmap); 540 } 541 542 /* Future-safe accessor for struct mm_struct's cpu_vm_mask. */ 543 static inline cpumask_t *mm_cpumask(struct mm_struct *mm) 544 { 545 return (struct cpumask *)&mm->cpu_bitmap; 546 } 547 548 struct mmu_gather; 549 extern void tlb_gather_mmu(struct mmu_gather *tlb, struct mm_struct *mm, 550 unsigned long start, unsigned long end); 551 extern void tlb_finish_mmu(struct mmu_gather *tlb, 552 unsigned long start, unsigned long end); 553 554 static inline void init_tlb_flush_pending(struct mm_struct *mm) 555 { 556 atomic_set(&mm->tlb_flush_pending, 0); 557 } 558 559 static inline void inc_tlb_flush_pending(struct mm_struct *mm) 560 { 561 atomic_inc(&mm->tlb_flush_pending); 562 /* 563 * The only time this value is relevant is when there are indeed pages 564 * to flush. And we'll only flush pages after changing them, which 565 * requires the PTL. 566 * 567 * So the ordering here is: 568 * 569 * atomic_inc(&mm->tlb_flush_pending); 570 * spin_lock(&ptl); 571 * ... 572 * set_pte_at(); 573 * spin_unlock(&ptl); 574 * 575 * spin_lock(&ptl) 576 * mm_tlb_flush_pending(); 577 * .... 578 * spin_unlock(&ptl); 579 * 580 * flush_tlb_range(); 581 * atomic_dec(&mm->tlb_flush_pending); 582 * 583 * Where the increment if constrained by the PTL unlock, it thus 584 * ensures that the increment is visible if the PTE modification is 585 * visible. After all, if there is no PTE modification, nobody cares 586 * about TLB flushes either. 587 * 588 * This very much relies on users (mm_tlb_flush_pending() and 589 * mm_tlb_flush_nested()) only caring about _specific_ PTEs (and 590 * therefore specific PTLs), because with SPLIT_PTE_PTLOCKS and RCpc 591 * locks (PPC) the unlock of one doesn't order against the lock of 592 * another PTL. 593 * 594 * The decrement is ordered by the flush_tlb_range(), such that 595 * mm_tlb_flush_pending() will not return false unless all flushes have 596 * completed. 597 */ 598 } 599 600 static inline void dec_tlb_flush_pending(struct mm_struct *mm) 601 { 602 /* 603 * See inc_tlb_flush_pending(). 604 * 605 * This cannot be smp_mb__before_atomic() because smp_mb() simply does 606 * not order against TLB invalidate completion, which is what we need. 607 * 608 * Therefore we must rely on tlb_flush_*() to guarantee order. 609 */ 610 atomic_dec(&mm->tlb_flush_pending); 611 } 612 613 static inline bool mm_tlb_flush_pending(struct mm_struct *mm) 614 { 615 /* 616 * Must be called after having acquired the PTL; orders against that 617 * PTLs release and therefore ensures that if we observe the modified 618 * PTE we must also observe the increment from inc_tlb_flush_pending(). 619 * 620 * That is, it only guarantees to return true if there is a flush 621 * pending for _this_ PTL. 622 */ 623 return atomic_read(&mm->tlb_flush_pending); 624 } 625 626 static inline bool mm_tlb_flush_nested(struct mm_struct *mm) 627 { 628 /* 629 * Similar to mm_tlb_flush_pending(), we must have acquired the PTL 630 * for which there is a TLB flush pending in order to guarantee 631 * we've seen both that PTE modification and the increment. 632 * 633 * (no requirement on actually still holding the PTL, that is irrelevant) 634 */ 635 return atomic_read(&mm->tlb_flush_pending) > 1; 636 } 637 638 struct vm_fault; 639 640 /** 641 * typedef vm_fault_t - Return type for page fault handlers. 642 * 643 * Page fault handlers return a bitmask of %VM_FAULT values. 644 */ 645 typedef __bitwise unsigned int vm_fault_t; 646 647 /** 648 * enum vm_fault_reason - Page fault handlers return a bitmask of 649 * these values to tell the core VM what happened when handling the 650 * fault. Used to decide whether a process gets delivered SIGBUS or 651 * just gets major/minor fault counters bumped up. 652 * 653 * @VM_FAULT_OOM: Out Of Memory 654 * @VM_FAULT_SIGBUS: Bad access 655 * @VM_FAULT_MAJOR: Page read from storage 656 * @VM_FAULT_WRITE: Special case for get_user_pages 657 * @VM_FAULT_HWPOISON: Hit poisoned small page 658 * @VM_FAULT_HWPOISON_LARGE: Hit poisoned large page. Index encoded 659 * in upper bits 660 * @VM_FAULT_SIGSEGV: segmentation fault 661 * @VM_FAULT_NOPAGE: ->fault installed the pte, not return page 662 * @VM_FAULT_LOCKED: ->fault locked the returned page 663 * @VM_FAULT_RETRY: ->fault blocked, must retry 664 * @VM_FAULT_FALLBACK: huge page fault failed, fall back to small 665 * @VM_FAULT_DONE_COW: ->fault has fully handled COW 666 * @VM_FAULT_NEEDDSYNC: ->fault did not modify page tables and needs 667 * fsync() to complete (for synchronous page faults 668 * in DAX) 669 * @VM_FAULT_HINDEX_MASK: mask HINDEX value 670 * 671 */ 672 enum vm_fault_reason { 673 VM_FAULT_OOM = (__force vm_fault_t)0x000001, 674 VM_FAULT_SIGBUS = (__force vm_fault_t)0x000002, 675 VM_FAULT_MAJOR = (__force vm_fault_t)0x000004, 676 VM_FAULT_WRITE = (__force vm_fault_t)0x000008, 677 VM_FAULT_HWPOISON = (__force vm_fault_t)0x000010, 678 VM_FAULT_HWPOISON_LARGE = (__force vm_fault_t)0x000020, 679 VM_FAULT_SIGSEGV = (__force vm_fault_t)0x000040, 680 VM_FAULT_NOPAGE = (__force vm_fault_t)0x000100, 681 VM_FAULT_LOCKED = (__force vm_fault_t)0x000200, 682 VM_FAULT_RETRY = (__force vm_fault_t)0x000400, 683 VM_FAULT_FALLBACK = (__force vm_fault_t)0x000800, 684 VM_FAULT_DONE_COW = (__force vm_fault_t)0x001000, 685 VM_FAULT_NEEDDSYNC = (__force vm_fault_t)0x002000, 686 VM_FAULT_HINDEX_MASK = (__force vm_fault_t)0x0f0000, 687 }; 688 689 /* Encode hstate index for a hwpoisoned large page */ 690 #define VM_FAULT_SET_HINDEX(x) ((__force vm_fault_t)((x) << 16)) 691 #define VM_FAULT_GET_HINDEX(x) (((__force unsigned int)(x) >> 16) & 0xf) 692 693 #define VM_FAULT_ERROR (VM_FAULT_OOM | VM_FAULT_SIGBUS | \ 694 VM_FAULT_SIGSEGV | VM_FAULT_HWPOISON | \ 695 VM_FAULT_HWPOISON_LARGE | VM_FAULT_FALLBACK) 696 697 #define VM_FAULT_RESULT_TRACE \ 698 { VM_FAULT_OOM, "OOM" }, \ 699 { VM_FAULT_SIGBUS, "SIGBUS" }, \ 700 { VM_FAULT_MAJOR, "MAJOR" }, \ 701 { VM_FAULT_WRITE, "WRITE" }, \ 702 { VM_FAULT_HWPOISON, "HWPOISON" }, \ 703 { VM_FAULT_HWPOISON_LARGE, "HWPOISON_LARGE" }, \ 704 { VM_FAULT_SIGSEGV, "SIGSEGV" }, \ 705 { VM_FAULT_NOPAGE, "NOPAGE" }, \ 706 { VM_FAULT_LOCKED, "LOCKED" }, \ 707 { VM_FAULT_RETRY, "RETRY" }, \ 708 { VM_FAULT_FALLBACK, "FALLBACK" }, \ 709 { VM_FAULT_DONE_COW, "DONE_COW" }, \ 710 { VM_FAULT_NEEDDSYNC, "NEEDDSYNC" } 711 712 struct vm_special_mapping { 713 const char *name; /* The name, e.g. "[vdso]". */ 714 715 /* 716 * If .fault is not provided, this points to a 717 * NULL-terminated array of pages that back the special mapping. 718 * 719 * This must not be NULL unless .fault is provided. 720 */ 721 struct page **pages; 722 723 /* 724 * If non-NULL, then this is called to resolve page faults 725 * on the special mapping. If used, .pages is not checked. 726 */ 727 vm_fault_t (*fault)(const struct vm_special_mapping *sm, 728 struct vm_area_struct *vma, 729 struct vm_fault *vmf); 730 731 int (*mremap)(const struct vm_special_mapping *sm, 732 struct vm_area_struct *new_vma); 733 }; 734 735 enum tlb_flush_reason { 736 TLB_FLUSH_ON_TASK_SWITCH, 737 TLB_REMOTE_SHOOTDOWN, 738 TLB_LOCAL_SHOOTDOWN, 739 TLB_LOCAL_MM_SHOOTDOWN, 740 TLB_REMOTE_SEND_IPI, 741 NR_TLB_FLUSH_REASONS, 742 }; 743 744 /* 745 * A swap entry has to fit into a "unsigned long", as the entry is hidden 746 * in the "index" field of the swapper address space. 747 */ 748 typedef struct { 749 unsigned long val; 750 } swp_entry_t; 751 752 #endif /* _LINUX_MM_TYPES_H */ 753