1 /* SPDX-License-Identifier: GPL-2.0+ */ 2 /* 3 * vma_internal.h 4 * 5 * Header providing userland wrappers and shims for the functionality provided 6 * by mm/vma_internal.h. 7 * 8 * We make the header guard the same as mm/vma_internal.h, so if this shim 9 * header is included, it precludes the inclusion of the kernel one. 10 */ 11 12 #ifndef __MM_VMA_INTERNAL_H 13 #define __MM_VMA_INTERNAL_H 14 15 #define __private 16 #define __bitwise 17 #define __randomize_layout 18 19 #define CONFIG_MMU 20 #define CONFIG_PER_VMA_LOCK 21 22 #include <stdlib.h> 23 24 #include <linux/list.h> 25 #include <linux/maple_tree.h> 26 #include <linux/mm.h> 27 #include <linux/rbtree.h> 28 #include <linux/refcount.h> 29 30 extern unsigned long stack_guard_gap; 31 #ifdef CONFIG_MMU 32 extern unsigned long mmap_min_addr; 33 extern unsigned long dac_mmap_min_addr; 34 #else 35 #define mmap_min_addr 0UL 36 #define dac_mmap_min_addr 0UL 37 #endif 38 39 #define VM_WARN_ON(_expr) (WARN_ON(_expr)) 40 #define VM_WARN_ON_ONCE(_expr) (WARN_ON_ONCE(_expr)) 41 #define VM_WARN_ON_VMG(_expr, _vmg) (WARN_ON(_expr)) 42 #define VM_BUG_ON(_expr) (BUG_ON(_expr)) 43 #define VM_BUG_ON_VMA(_expr, _vma) (BUG_ON(_expr)) 44 45 #define MMF_HAS_MDWE 28 46 47 #define VM_NONE 0x00000000 48 #define VM_READ 0x00000001 49 #define VM_WRITE 0x00000002 50 #define VM_EXEC 0x00000004 51 #define VM_SHARED 0x00000008 52 #define VM_MAYREAD 0x00000010 53 #define VM_MAYWRITE 0x00000020 54 #define VM_MAYEXEC 0x00000040 55 #define VM_GROWSDOWN 0x00000100 56 #define VM_PFNMAP 0x00000400 57 #define VM_LOCKED 0x00002000 58 #define VM_IO 0x00004000 59 #define VM_SEQ_READ 0x00008000 /* App will access data sequentially */ 60 #define VM_RAND_READ 0x00010000 /* App will not benefit from clustered reads */ 61 #define VM_DONTEXPAND 0x00040000 62 #define VM_LOCKONFAULT 0x00080000 63 #define VM_ACCOUNT 0x00100000 64 #define VM_NORESERVE 0x00200000 65 #define VM_MIXEDMAP 0x10000000 66 #define VM_STACK VM_GROWSDOWN 67 #define VM_SHADOW_STACK VM_NONE 68 #define VM_SOFTDIRTY 0 69 #define VM_ARCH_1 0x01000000 /* Architecture-specific flag */ 70 #define VM_GROWSUP VM_NONE 71 72 #define VM_ACCESS_FLAGS (VM_READ | VM_WRITE | VM_EXEC) 73 #define VM_SPECIAL (VM_IO | VM_DONTEXPAND | VM_PFNMAP | VM_MIXEDMAP) 74 75 #ifdef CONFIG_STACK_GROWSUP 76 #define VM_STACK VM_GROWSUP 77 #define VM_STACK_EARLY VM_GROWSDOWN 78 #else 79 #define VM_STACK VM_GROWSDOWN 80 #define VM_STACK_EARLY 0 81 #endif 82 83 #define DEFAULT_MAP_WINDOW ((1UL << 47) - PAGE_SIZE) 84 #define TASK_SIZE_LOW DEFAULT_MAP_WINDOW 85 #define TASK_SIZE_MAX DEFAULT_MAP_WINDOW 86 #define STACK_TOP TASK_SIZE_LOW 87 #define STACK_TOP_MAX TASK_SIZE_MAX 88 89 /* This mask represents all the VMA flag bits used by mlock */ 90 #define VM_LOCKED_MASK (VM_LOCKED | VM_LOCKONFAULT) 91 92 #define TASK_EXEC ((current->personality & READ_IMPLIES_EXEC) ? VM_EXEC : 0) 93 94 #define VM_DATA_FLAGS_TSK_EXEC (VM_READ | VM_WRITE | TASK_EXEC | \ 95 VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC) 96 97 #define VM_DATA_DEFAULT_FLAGS VM_DATA_FLAGS_TSK_EXEC 98 99 #define VM_STARTGAP_FLAGS (VM_GROWSDOWN | VM_SHADOW_STACK) 100 101 #define VM_STACK_DEFAULT_FLAGS VM_DATA_DEFAULT_FLAGS 102 #define VM_STACK_FLAGS (VM_STACK | VM_STACK_DEFAULT_FLAGS | VM_ACCOUNT) 103 #define VM_STACK_INCOMPLETE_SETUP (VM_RAND_READ | VM_SEQ_READ | VM_STACK_EARLY) 104 105 #define RLIMIT_STACK 3 /* max stack size */ 106 #define RLIMIT_MEMLOCK 8 /* max locked-in-memory address space */ 107 108 #define CAP_IPC_LOCK 14 109 110 #ifdef CONFIG_64BIT 111 #define VM_SEALED_BIT 42 112 #define VM_SEALED BIT(VM_SEALED_BIT) 113 #else 114 #define VM_SEALED VM_NONE 115 #endif 116 117 #define FIRST_USER_ADDRESS 0UL 118 #define USER_PGTABLES_CEILING 0UL 119 120 #define vma_policy(vma) NULL 121 122 #define down_write_nest_lock(sem, nest_lock) 123 124 #define pgprot_val(x) ((x).pgprot) 125 #define __pgprot(x) ((pgprot_t) { (x) } ) 126 127 #define for_each_vma(__vmi, __vma) \ 128 while (((__vma) = vma_next(&(__vmi))) != NULL) 129 130 /* The MM code likes to work with exclusive end addresses */ 131 #define for_each_vma_range(__vmi, __vma, __end) \ 132 while (((__vma) = vma_find(&(__vmi), (__end))) != NULL) 133 134 #define offset_in_page(p) ((unsigned long)(p) & ~PAGE_MASK) 135 136 #define PHYS_PFN(x) ((unsigned long)((x) >> PAGE_SHIFT)) 137 138 #define test_and_set_bit(nr, addr) __test_and_set_bit(nr, addr) 139 #define test_and_clear_bit(nr, addr) __test_and_clear_bit(nr, addr) 140 141 #define TASK_SIZE ((1ul << 47)-PAGE_SIZE) 142 143 #define AS_MM_ALL_LOCKS 2 144 145 /* We hardcode this for now. */ 146 #define sysctl_max_map_count 0x1000000UL 147 148 #define pgoff_t unsigned long 149 typedef unsigned long pgprotval_t; 150 typedef struct pgprot { pgprotval_t pgprot; } pgprot_t; 151 typedef unsigned long vm_flags_t; 152 typedef __bitwise unsigned int vm_fault_t; 153 154 /* 155 * The shared stubs do not implement this, it amounts to an fprintf(STDERR,...) 156 * either way :) 157 */ 158 #define pr_warn_once pr_err 159 160 #define data_race(expr) expr 161 162 #define ASSERT_EXCLUSIVE_WRITER(x) 163 164 /** 165 * swap - swap values of @a and @b 166 * @a: first value 167 * @b: second value 168 */ 169 #define swap(a, b) \ 170 do { typeof(a) __tmp = (a); (a) = (b); (b) = __tmp; } while (0) 171 172 struct kref { 173 refcount_t refcount; 174 }; 175 176 /* 177 * Define the task command name length as enum, then it can be visible to 178 * BPF programs. 179 */ 180 enum { 181 TASK_COMM_LEN = 16, 182 }; 183 184 /* 185 * Flags for bug emulation. 186 * 187 * These occupy the top three bytes. 188 */ 189 enum { 190 READ_IMPLIES_EXEC = 0x0400000, 191 }; 192 193 struct task_struct { 194 char comm[TASK_COMM_LEN]; 195 pid_t pid; 196 struct mm_struct *mm; 197 198 /* Used for emulating ABI behavior of previous Linux versions: */ 199 unsigned int personality; 200 }; 201 202 struct task_struct *get_current(void); 203 #define current get_current() 204 205 struct anon_vma { 206 struct anon_vma *root; 207 struct rb_root_cached rb_root; 208 209 /* Test fields. */ 210 bool was_cloned; 211 bool was_unlinked; 212 }; 213 214 struct anon_vma_chain { 215 struct anon_vma *anon_vma; 216 struct list_head same_vma; 217 }; 218 219 struct anon_vma_name { 220 struct kref kref; 221 /* The name needs to be at the end because it is dynamically sized. */ 222 char name[]; 223 }; 224 225 struct vma_iterator { 226 struct ma_state mas; 227 }; 228 229 #define VMA_ITERATOR(name, __mm, __addr) \ 230 struct vma_iterator name = { \ 231 .mas = { \ 232 .tree = &(__mm)->mm_mt, \ 233 .index = __addr, \ 234 .node = NULL, \ 235 .status = ma_start, \ 236 }, \ 237 } 238 239 struct address_space { 240 struct rb_root_cached i_mmap; 241 unsigned long flags; 242 atomic_t i_mmap_writable; 243 }; 244 245 struct vm_userfaultfd_ctx {}; 246 struct mempolicy {}; 247 struct mmu_gather {}; 248 struct mutex {}; 249 #define DEFINE_MUTEX(mutexname) \ 250 struct mutex mutexname = {} 251 252 struct mm_struct { 253 struct maple_tree mm_mt; 254 int map_count; /* number of VMAs */ 255 unsigned long total_vm; /* Total pages mapped */ 256 unsigned long locked_vm; /* Pages that have PG_mlocked set */ 257 unsigned long data_vm; /* VM_WRITE & ~VM_SHARED & ~VM_STACK */ 258 unsigned long exec_vm; /* VM_EXEC & ~VM_WRITE & ~VM_STACK */ 259 unsigned long stack_vm; /* VM_STACK */ 260 261 unsigned long def_flags; 262 263 unsigned long flags; /* Must use atomic bitops to access */ 264 }; 265 266 struct vm_area_struct; 267 268 /* 269 * Describes a VMA that is about to be mmap()'ed. Drivers may choose to 270 * manipulate mutable fields which will cause those fields to be updated in the 271 * resultant VMA. 272 * 273 * Helper functions are not required for manipulating any field. 274 */ 275 struct vm_area_desc { 276 /* Immutable state. */ 277 struct mm_struct *mm; 278 unsigned long start; 279 unsigned long end; 280 281 /* Mutable fields. Populated with initial state. */ 282 pgoff_t pgoff; 283 struct file *file; 284 vm_flags_t vm_flags; 285 pgprot_t page_prot; 286 287 /* Write-only fields. */ 288 const struct vm_operations_struct *vm_ops; 289 void *private_data; 290 }; 291 292 struct file_operations { 293 int (*mmap)(struct file *, struct vm_area_struct *); 294 int (*mmap_prepare)(struct vm_area_desc *); 295 }; 296 297 struct file { 298 struct address_space *f_mapping; 299 const struct file_operations *f_op; 300 }; 301 302 #define VMA_LOCK_OFFSET 0x40000000 303 304 typedef struct { unsigned long v; } freeptr_t; 305 306 struct vm_area_struct { 307 /* The first cache line has the info for VMA tree walking. */ 308 309 union { 310 struct { 311 /* VMA covers [vm_start; vm_end) addresses within mm */ 312 unsigned long vm_start; 313 unsigned long vm_end; 314 }; 315 freeptr_t vm_freeptr; /* Pointer used by SLAB_TYPESAFE_BY_RCU */ 316 }; 317 318 struct mm_struct *vm_mm; /* The address space we belong to. */ 319 pgprot_t vm_page_prot; /* Access permissions of this VMA. */ 320 321 /* 322 * Flags, see mm.h. 323 * To modify use vm_flags_{init|reset|set|clear|mod} functions. 324 */ 325 union { 326 const vm_flags_t vm_flags; 327 vm_flags_t __private __vm_flags; 328 }; 329 330 #ifdef CONFIG_PER_VMA_LOCK 331 /* 332 * Can only be written (using WRITE_ONCE()) while holding both: 333 * - mmap_lock (in write mode) 334 * - vm_refcnt bit at VMA_LOCK_OFFSET is set 335 * Can be read reliably while holding one of: 336 * - mmap_lock (in read or write mode) 337 * - vm_refcnt bit at VMA_LOCK_OFFSET is set or vm_refcnt > 1 338 * Can be read unreliably (using READ_ONCE()) for pessimistic bailout 339 * while holding nothing (except RCU to keep the VMA struct allocated). 340 * 341 * This sequence counter is explicitly allowed to overflow; sequence 342 * counter reuse can only lead to occasional unnecessary use of the 343 * slowpath. 344 */ 345 unsigned int vm_lock_seq; 346 #endif 347 348 /* 349 * A file's MAP_PRIVATE vma can be in both i_mmap tree and anon_vma 350 * list, after a COW of one of the file pages. A MAP_SHARED vma 351 * can only be in the i_mmap tree. An anonymous MAP_PRIVATE, stack 352 * or brk vma (with NULL file) can only be in an anon_vma list. 353 */ 354 struct list_head anon_vma_chain; /* Serialized by mmap_lock & 355 * page_table_lock */ 356 struct anon_vma *anon_vma; /* Serialized by page_table_lock */ 357 358 /* Function pointers to deal with this struct. */ 359 const struct vm_operations_struct *vm_ops; 360 361 /* Information about our backing store: */ 362 unsigned long vm_pgoff; /* Offset (within vm_file) in PAGE_SIZE 363 units */ 364 struct file * vm_file; /* File we map to (can be NULL). */ 365 void * vm_private_data; /* was vm_pte (shared mem) */ 366 367 #ifdef CONFIG_SWAP 368 atomic_long_t swap_readahead_info; 369 #endif 370 #ifndef CONFIG_MMU 371 struct vm_region *vm_region; /* NOMMU mapping region */ 372 #endif 373 #ifdef CONFIG_NUMA 374 struct mempolicy *vm_policy; /* NUMA policy for the VMA */ 375 #endif 376 #ifdef CONFIG_NUMA_BALANCING 377 struct vma_numab_state *numab_state; /* NUMA Balancing state */ 378 #endif 379 #ifdef CONFIG_PER_VMA_LOCK 380 /* Unstable RCU readers are allowed to read this. */ 381 refcount_t vm_refcnt; 382 #endif 383 /* 384 * For areas with an address space and backing store, 385 * linkage into the address_space->i_mmap interval tree. 386 * 387 */ 388 struct { 389 struct rb_node rb; 390 unsigned long rb_subtree_last; 391 } shared; 392 #ifdef CONFIG_ANON_VMA_NAME 393 /* 394 * For private and shared anonymous mappings, a pointer to a null 395 * terminated string containing the name given to the vma, or NULL if 396 * unnamed. Serialized by mmap_lock. Use anon_vma_name to access. 397 */ 398 struct anon_vma_name *anon_name; 399 #endif 400 struct vm_userfaultfd_ctx vm_userfaultfd_ctx; 401 } __randomize_layout; 402 403 struct vm_fault {}; 404 405 struct vm_operations_struct { 406 void (*open)(struct vm_area_struct * area); 407 /** 408 * @close: Called when the VMA is being removed from the MM. 409 * Context: User context. May sleep. Caller holds mmap_lock. 410 */ 411 void (*close)(struct vm_area_struct * area); 412 /* Called any time before splitting to check if it's allowed */ 413 int (*may_split)(struct vm_area_struct *area, unsigned long addr); 414 int (*mremap)(struct vm_area_struct *area); 415 /* 416 * Called by mprotect() to make driver-specific permission 417 * checks before mprotect() is finalised. The VMA must not 418 * be modified. Returns 0 if mprotect() can proceed. 419 */ 420 int (*mprotect)(struct vm_area_struct *vma, unsigned long start, 421 unsigned long end, unsigned long newflags); 422 vm_fault_t (*fault)(struct vm_fault *vmf); 423 vm_fault_t (*huge_fault)(struct vm_fault *vmf, unsigned int order); 424 vm_fault_t (*map_pages)(struct vm_fault *vmf, 425 pgoff_t start_pgoff, pgoff_t end_pgoff); 426 unsigned long (*pagesize)(struct vm_area_struct * area); 427 428 /* notification that a previously read-only page is about to become 429 * writable, if an error is returned it will cause a SIGBUS */ 430 vm_fault_t (*page_mkwrite)(struct vm_fault *vmf); 431 432 /* same as page_mkwrite when using VM_PFNMAP|VM_MIXEDMAP */ 433 vm_fault_t (*pfn_mkwrite)(struct vm_fault *vmf); 434 435 /* called by access_process_vm when get_user_pages() fails, typically 436 * for use by special VMAs. See also generic_access_phys() for a generic 437 * implementation useful for any iomem mapping. 438 */ 439 int (*access)(struct vm_area_struct *vma, unsigned long addr, 440 void *buf, int len, int write); 441 442 /* Called by the /proc/PID/maps code to ask the vma whether it 443 * has a special name. Returning non-NULL will also cause this 444 * vma to be dumped unconditionally. */ 445 const char *(*name)(struct vm_area_struct *vma); 446 447 #ifdef CONFIG_NUMA 448 /* 449 * set_policy() op must add a reference to any non-NULL @new mempolicy 450 * to hold the policy upon return. Caller should pass NULL @new to 451 * remove a policy and fall back to surrounding context--i.e. do not 452 * install a MPOL_DEFAULT policy, nor the task or system default 453 * mempolicy. 454 */ 455 int (*set_policy)(struct vm_area_struct *vma, struct mempolicy *new); 456 457 /* 458 * get_policy() op must add reference [mpol_get()] to any policy at 459 * (vma,addr) marked as MPOL_SHARED. The shared policy infrastructure 460 * in mm/mempolicy.c will do this automatically. 461 * get_policy() must NOT add a ref if the policy at (vma,addr) is not 462 * marked as MPOL_SHARED. vma policies are protected by the mmap_lock. 463 * If no [shared/vma] mempolicy exists at the addr, get_policy() op 464 * must return NULL--i.e., do not "fallback" to task or system default 465 * policy. 466 */ 467 struct mempolicy *(*get_policy)(struct vm_area_struct *vma, 468 unsigned long addr, pgoff_t *ilx); 469 #endif 470 /* 471 * Called by vm_normal_page() for special PTEs to find the 472 * page for @addr. This is useful if the default behavior 473 * (using pte_page()) would not find the correct page. 474 */ 475 struct page *(*find_special_page)(struct vm_area_struct *vma, 476 unsigned long addr); 477 }; 478 479 struct vm_unmapped_area_info { 480 #define VM_UNMAPPED_AREA_TOPDOWN 1 481 unsigned long flags; 482 unsigned long length; 483 unsigned long low_limit; 484 unsigned long high_limit; 485 unsigned long align_mask; 486 unsigned long align_offset; 487 unsigned long start_gap; 488 }; 489 490 struct pagetable_move_control { 491 struct vm_area_struct *old; /* Source VMA. */ 492 struct vm_area_struct *new; /* Destination VMA. */ 493 unsigned long old_addr; /* Address from which the move begins. */ 494 unsigned long old_end; /* Exclusive address at which old range ends. */ 495 unsigned long new_addr; /* Address to move page tables to. */ 496 unsigned long len_in; /* Bytes to remap specified by user. */ 497 498 bool need_rmap_locks; /* Do rmap locks need to be taken? */ 499 bool for_stack; /* Is this an early temp stack being moved? */ 500 }; 501 502 #define PAGETABLE_MOVE(name, old_, new_, old_addr_, new_addr_, len_) \ 503 struct pagetable_move_control name = { \ 504 .old = old_, \ 505 .new = new_, \ 506 .old_addr = old_addr_, \ 507 .old_end = (old_addr_) + (len_), \ 508 .new_addr = new_addr_, \ 509 .len_in = len_, \ 510 } 511 512 struct kmem_cache_args { 513 /** 514 * @align: The required alignment for the objects. 515 * 516 * %0 means no specific alignment is requested. 517 */ 518 unsigned int align; 519 /** 520 * @useroffset: Usercopy region offset. 521 * 522 * %0 is a valid offset, when @usersize is non-%0 523 */ 524 unsigned int useroffset; 525 /** 526 * @usersize: Usercopy region size. 527 * 528 * %0 means no usercopy region is specified. 529 */ 530 unsigned int usersize; 531 /** 532 * @freeptr_offset: Custom offset for the free pointer 533 * in &SLAB_TYPESAFE_BY_RCU caches 534 * 535 * By default &SLAB_TYPESAFE_BY_RCU caches place the free pointer 536 * outside of the object. This might cause the object to grow in size. 537 * Cache creators that have a reason to avoid this can specify a custom 538 * free pointer offset in their struct where the free pointer will be 539 * placed. 540 * 541 * Note that placing the free pointer inside the object requires the 542 * caller to ensure that no fields are invalidated that are required to 543 * guard against object recycling (See &SLAB_TYPESAFE_BY_RCU for 544 * details). 545 * 546 * Using %0 as a value for @freeptr_offset is valid. If @freeptr_offset 547 * is specified, %use_freeptr_offset must be set %true. 548 * 549 * Note that @ctor currently isn't supported with custom free pointers 550 * as a @ctor requires an external free pointer. 551 */ 552 unsigned int freeptr_offset; 553 /** 554 * @use_freeptr_offset: Whether a @freeptr_offset is used. 555 */ 556 bool use_freeptr_offset; 557 /** 558 * @ctor: A constructor for the objects. 559 * 560 * The constructor is invoked for each object in a newly allocated slab 561 * page. It is the cache user's responsibility to free object in the 562 * same state as after calling the constructor, or deal appropriately 563 * with any differences between a freshly constructed and a reallocated 564 * object. 565 * 566 * %NULL means no constructor. 567 */ 568 void (*ctor)(void *); 569 }; 570 571 static inline void vma_iter_invalidate(struct vma_iterator *vmi) 572 { 573 mas_pause(&vmi->mas); 574 } 575 576 static inline pgprot_t pgprot_modify(pgprot_t oldprot, pgprot_t newprot) 577 { 578 return __pgprot(pgprot_val(oldprot) | pgprot_val(newprot)); 579 } 580 581 static inline pgprot_t vm_get_page_prot(vm_flags_t vm_flags) 582 { 583 return __pgprot(vm_flags); 584 } 585 586 static inline bool is_shared_maywrite(vm_flags_t vm_flags) 587 { 588 return (vm_flags & (VM_SHARED | VM_MAYWRITE)) == 589 (VM_SHARED | VM_MAYWRITE); 590 } 591 592 static inline bool vma_is_shared_maywrite(struct vm_area_struct *vma) 593 { 594 return is_shared_maywrite(vma->vm_flags); 595 } 596 597 static inline struct vm_area_struct *vma_next(struct vma_iterator *vmi) 598 { 599 /* 600 * Uses mas_find() to get the first VMA when the iterator starts. 601 * Calling mas_next() could skip the first entry. 602 */ 603 return mas_find(&vmi->mas, ULONG_MAX); 604 } 605 606 /* 607 * WARNING: to avoid racing with vma_mark_attached()/vma_mark_detached(), these 608 * assertions should be made either under mmap_write_lock or when the object 609 * has been isolated under mmap_write_lock, ensuring no competing writers. 610 */ 611 static inline void vma_assert_attached(struct vm_area_struct *vma) 612 { 613 WARN_ON_ONCE(!refcount_read(&vma->vm_refcnt)); 614 } 615 616 static inline void vma_assert_detached(struct vm_area_struct *vma) 617 { 618 WARN_ON_ONCE(refcount_read(&vma->vm_refcnt)); 619 } 620 621 static inline void vma_assert_write_locked(struct vm_area_struct *); 622 static inline void vma_mark_attached(struct vm_area_struct *vma) 623 { 624 vma_assert_write_locked(vma); 625 vma_assert_detached(vma); 626 refcount_set_release(&vma->vm_refcnt, 1); 627 } 628 629 static inline void vma_mark_detached(struct vm_area_struct *vma) 630 { 631 vma_assert_write_locked(vma); 632 vma_assert_attached(vma); 633 /* We are the only writer, so no need to use vma_refcount_put(). */ 634 if (unlikely(!refcount_dec_and_test(&vma->vm_refcnt))) { 635 /* 636 * Reader must have temporarily raised vm_refcnt but it will 637 * drop it without using the vma since vma is write-locked. 638 */ 639 } 640 } 641 642 extern const struct vm_operations_struct vma_dummy_vm_ops; 643 644 extern unsigned long rlimit(unsigned int limit); 645 646 static inline void vma_init(struct vm_area_struct *vma, struct mm_struct *mm) 647 { 648 memset(vma, 0, sizeof(*vma)); 649 vma->vm_mm = mm; 650 vma->vm_ops = &vma_dummy_vm_ops; 651 INIT_LIST_HEAD(&vma->anon_vma_chain); 652 vma->vm_lock_seq = UINT_MAX; 653 } 654 655 struct kmem_cache { 656 const char *name; 657 size_t object_size; 658 struct kmem_cache_args *args; 659 }; 660 661 static inline struct kmem_cache *__kmem_cache_create(const char *name, 662 size_t object_size, 663 struct kmem_cache_args *args) 664 { 665 struct kmem_cache *ret = malloc(sizeof(struct kmem_cache)); 666 667 ret->name = name; 668 ret->object_size = object_size; 669 ret->args = args; 670 671 return ret; 672 } 673 674 #define kmem_cache_create(__name, __object_size, __args, ...) \ 675 __kmem_cache_create((__name), (__object_size), (__args)) 676 677 static inline void *kmem_cache_alloc(struct kmem_cache *s, gfp_t gfpflags) 678 { 679 (void)gfpflags; 680 681 return calloc(s->object_size, 1); 682 } 683 684 static inline void kmem_cache_free(struct kmem_cache *s, void *x) 685 { 686 free(x); 687 } 688 689 /* 690 * These are defined in vma.h, but sadly vm_stat_account() is referenced by 691 * kernel/fork.c, so we have to these broadly available there, and temporarily 692 * define them here to resolve the dependency cycle. 693 */ 694 695 #define is_exec_mapping(flags) \ 696 ((flags & (VM_EXEC | VM_WRITE | VM_STACK)) == VM_EXEC) 697 698 #define is_stack_mapping(flags) \ 699 (((flags & VM_STACK) == VM_STACK) || (flags & VM_SHADOW_STACK)) 700 701 #define is_data_mapping(flags) \ 702 ((flags & (VM_WRITE | VM_SHARED | VM_STACK)) == VM_WRITE) 703 704 static inline void vm_stat_account(struct mm_struct *mm, vm_flags_t flags, 705 long npages) 706 { 707 WRITE_ONCE(mm->total_vm, READ_ONCE(mm->total_vm)+npages); 708 709 if (is_exec_mapping(flags)) 710 mm->exec_vm += npages; 711 else if (is_stack_mapping(flags)) 712 mm->stack_vm += npages; 713 else if (is_data_mapping(flags)) 714 mm->data_vm += npages; 715 } 716 717 #undef is_exec_mapping 718 #undef is_stack_mapping 719 #undef is_data_mapping 720 721 /* Currently stubbed but we may later wish to un-stub. */ 722 static inline void vm_acct_memory(long pages); 723 static inline void vm_unacct_memory(long pages) 724 { 725 vm_acct_memory(-pages); 726 } 727 728 static inline void mapping_allow_writable(struct address_space *mapping) 729 { 730 atomic_inc(&mapping->i_mmap_writable); 731 } 732 733 static inline void vma_set_range(struct vm_area_struct *vma, 734 unsigned long start, unsigned long end, 735 pgoff_t pgoff) 736 { 737 vma->vm_start = start; 738 vma->vm_end = end; 739 vma->vm_pgoff = pgoff; 740 } 741 742 static inline 743 struct vm_area_struct *vma_find(struct vma_iterator *vmi, unsigned long max) 744 { 745 return mas_find(&vmi->mas, max - 1); 746 } 747 748 static inline int vma_iter_clear_gfp(struct vma_iterator *vmi, 749 unsigned long start, unsigned long end, gfp_t gfp) 750 { 751 __mas_set_range(&vmi->mas, start, end - 1); 752 mas_store_gfp(&vmi->mas, NULL, gfp); 753 if (unlikely(mas_is_err(&vmi->mas))) 754 return -ENOMEM; 755 756 return 0; 757 } 758 759 static inline void mmap_assert_locked(struct mm_struct *); 760 static inline struct vm_area_struct *find_vma_intersection(struct mm_struct *mm, 761 unsigned long start_addr, 762 unsigned long end_addr) 763 { 764 unsigned long index = start_addr; 765 766 mmap_assert_locked(mm); 767 return mt_find(&mm->mm_mt, &index, end_addr - 1); 768 } 769 770 static inline 771 struct vm_area_struct *vma_lookup(struct mm_struct *mm, unsigned long addr) 772 { 773 return mtree_load(&mm->mm_mt, addr); 774 } 775 776 static inline struct vm_area_struct *vma_prev(struct vma_iterator *vmi) 777 { 778 return mas_prev(&vmi->mas, 0); 779 } 780 781 static inline void vma_iter_set(struct vma_iterator *vmi, unsigned long addr) 782 { 783 mas_set(&vmi->mas, addr); 784 } 785 786 static inline bool vma_is_anonymous(struct vm_area_struct *vma) 787 { 788 return !vma->vm_ops; 789 } 790 791 /* Defined in vma.h, so temporarily define here to avoid circular dependency. */ 792 #define vma_iter_load(vmi) \ 793 mas_walk(&(vmi)->mas) 794 795 static inline struct vm_area_struct * 796 find_vma_prev(struct mm_struct *mm, unsigned long addr, 797 struct vm_area_struct **pprev) 798 { 799 struct vm_area_struct *vma; 800 VMA_ITERATOR(vmi, mm, addr); 801 802 vma = vma_iter_load(&vmi); 803 *pprev = vma_prev(&vmi); 804 if (!vma) 805 vma = vma_next(&vmi); 806 return vma; 807 } 808 809 #undef vma_iter_load 810 811 static inline void vma_iter_init(struct vma_iterator *vmi, 812 struct mm_struct *mm, unsigned long addr) 813 { 814 mas_init(&vmi->mas, &mm->mm_mt, addr); 815 } 816 817 /* Stubbed functions. */ 818 819 static inline struct anon_vma_name *anon_vma_name(struct vm_area_struct *vma) 820 { 821 return NULL; 822 } 823 824 static inline bool is_mergeable_vm_userfaultfd_ctx(struct vm_area_struct *vma, 825 struct vm_userfaultfd_ctx vm_ctx) 826 { 827 return true; 828 } 829 830 static inline bool anon_vma_name_eq(struct anon_vma_name *anon_name1, 831 struct anon_vma_name *anon_name2) 832 { 833 return true; 834 } 835 836 static inline void might_sleep(void) 837 { 838 } 839 840 static inline unsigned long vma_pages(struct vm_area_struct *vma) 841 { 842 return (vma->vm_end - vma->vm_start) >> PAGE_SHIFT; 843 } 844 845 static inline void fput(struct file *) 846 { 847 } 848 849 static inline void mpol_put(struct mempolicy *) 850 { 851 } 852 853 static inline void lru_add_drain(void) 854 { 855 } 856 857 static inline void tlb_gather_mmu(struct mmu_gather *, struct mm_struct *) 858 { 859 } 860 861 static inline void update_hiwater_rss(struct mm_struct *) 862 { 863 } 864 865 static inline void update_hiwater_vm(struct mm_struct *) 866 { 867 } 868 869 static inline void unmap_vmas(struct mmu_gather *tlb, struct ma_state *mas, 870 struct vm_area_struct *vma, unsigned long start_addr, 871 unsigned long end_addr, unsigned long tree_end, 872 bool mm_wr_locked) 873 { 874 (void)tlb; 875 (void)mas; 876 (void)vma; 877 (void)start_addr; 878 (void)end_addr; 879 (void)tree_end; 880 (void)mm_wr_locked; 881 } 882 883 static inline void free_pgtables(struct mmu_gather *tlb, struct ma_state *mas, 884 struct vm_area_struct *vma, unsigned long floor, 885 unsigned long ceiling, bool mm_wr_locked) 886 { 887 (void)tlb; 888 (void)mas; 889 (void)vma; 890 (void)floor; 891 (void)ceiling; 892 (void)mm_wr_locked; 893 } 894 895 static inline void mapping_unmap_writable(struct address_space *) 896 { 897 } 898 899 static inline void flush_dcache_mmap_lock(struct address_space *) 900 { 901 } 902 903 static inline void tlb_finish_mmu(struct mmu_gather *) 904 { 905 } 906 907 static inline struct file *get_file(struct file *f) 908 { 909 return f; 910 } 911 912 static inline int vma_dup_policy(struct vm_area_struct *, struct vm_area_struct *) 913 { 914 return 0; 915 } 916 917 static inline int anon_vma_clone(struct vm_area_struct *dst, struct vm_area_struct *src) 918 { 919 /* For testing purposes. We indicate that an anon_vma has been cloned. */ 920 if (src->anon_vma != NULL) { 921 dst->anon_vma = src->anon_vma; 922 dst->anon_vma->was_cloned = true; 923 } 924 925 return 0; 926 } 927 928 static inline void vma_start_write(struct vm_area_struct *vma) 929 { 930 /* Used to indicate to tests that a write operation has begun. */ 931 vma->vm_lock_seq++; 932 } 933 934 static inline void vma_adjust_trans_huge(struct vm_area_struct *vma, 935 unsigned long start, 936 unsigned long end, 937 struct vm_area_struct *next) 938 { 939 (void)vma; 940 (void)start; 941 (void)end; 942 (void)next; 943 } 944 945 static inline void hugetlb_split(struct vm_area_struct *, unsigned long) {} 946 947 static inline void vma_iter_free(struct vma_iterator *vmi) 948 { 949 mas_destroy(&vmi->mas); 950 } 951 952 static inline 953 struct vm_area_struct *vma_iter_next_range(struct vma_iterator *vmi) 954 { 955 return mas_next_range(&vmi->mas, ULONG_MAX); 956 } 957 958 static inline void vm_acct_memory(long pages) 959 { 960 } 961 962 static inline void vma_interval_tree_insert(struct vm_area_struct *, 963 struct rb_root_cached *) 964 { 965 } 966 967 static inline void vma_interval_tree_remove(struct vm_area_struct *, 968 struct rb_root_cached *) 969 { 970 } 971 972 static inline void flush_dcache_mmap_unlock(struct address_space *) 973 { 974 } 975 976 static inline void anon_vma_interval_tree_insert(struct anon_vma_chain*, 977 struct rb_root_cached *) 978 { 979 } 980 981 static inline void anon_vma_interval_tree_remove(struct anon_vma_chain*, 982 struct rb_root_cached *) 983 { 984 } 985 986 static inline void uprobe_mmap(struct vm_area_struct *) 987 { 988 } 989 990 static inline void uprobe_munmap(struct vm_area_struct *vma, 991 unsigned long start, unsigned long end) 992 { 993 (void)vma; 994 (void)start; 995 (void)end; 996 } 997 998 static inline void i_mmap_lock_write(struct address_space *) 999 { 1000 } 1001 1002 static inline void anon_vma_lock_write(struct anon_vma *) 1003 { 1004 } 1005 1006 static inline void vma_assert_write_locked(struct vm_area_struct *) 1007 { 1008 } 1009 1010 static inline void unlink_anon_vmas(struct vm_area_struct *vma) 1011 { 1012 /* For testing purposes, indicate that the anon_vma was unlinked. */ 1013 vma->anon_vma->was_unlinked = true; 1014 } 1015 1016 static inline void anon_vma_unlock_write(struct anon_vma *) 1017 { 1018 } 1019 1020 static inline void i_mmap_unlock_write(struct address_space *) 1021 { 1022 } 1023 1024 static inline void anon_vma_merge(struct vm_area_struct *, 1025 struct vm_area_struct *) 1026 { 1027 } 1028 1029 static inline int userfaultfd_unmap_prep(struct vm_area_struct *vma, 1030 unsigned long start, 1031 unsigned long end, 1032 struct list_head *unmaps) 1033 { 1034 (void)vma; 1035 (void)start; 1036 (void)end; 1037 (void)unmaps; 1038 1039 return 0; 1040 } 1041 1042 static inline void mmap_write_downgrade(struct mm_struct *) 1043 { 1044 } 1045 1046 static inline void mmap_read_unlock(struct mm_struct *) 1047 { 1048 } 1049 1050 static inline void mmap_write_unlock(struct mm_struct *) 1051 { 1052 } 1053 1054 static inline int mmap_write_lock_killable(struct mm_struct *) 1055 { 1056 return 0; 1057 } 1058 1059 static inline bool can_modify_mm(struct mm_struct *mm, 1060 unsigned long start, 1061 unsigned long end) 1062 { 1063 (void)mm; 1064 (void)start; 1065 (void)end; 1066 1067 return true; 1068 } 1069 1070 static inline void arch_unmap(struct mm_struct *mm, 1071 unsigned long start, 1072 unsigned long end) 1073 { 1074 (void)mm; 1075 (void)start; 1076 (void)end; 1077 } 1078 1079 static inline void mmap_assert_locked(struct mm_struct *) 1080 { 1081 } 1082 1083 static inline bool mpol_equal(struct mempolicy *, struct mempolicy *) 1084 { 1085 return true; 1086 } 1087 1088 static inline void khugepaged_enter_vma(struct vm_area_struct *vma, 1089 vm_flags_t vm_flags) 1090 { 1091 (void)vma; 1092 (void)vm_flags; 1093 } 1094 1095 static inline bool mapping_can_writeback(struct address_space *) 1096 { 1097 return true; 1098 } 1099 1100 static inline bool is_vm_hugetlb_page(struct vm_area_struct *) 1101 { 1102 return false; 1103 } 1104 1105 static inline bool vma_soft_dirty_enabled(struct vm_area_struct *) 1106 { 1107 return false; 1108 } 1109 1110 static inline bool userfaultfd_wp(struct vm_area_struct *) 1111 { 1112 return false; 1113 } 1114 1115 static inline void mmap_assert_write_locked(struct mm_struct *) 1116 { 1117 } 1118 1119 static inline void mutex_lock(struct mutex *) 1120 { 1121 } 1122 1123 static inline void mutex_unlock(struct mutex *) 1124 { 1125 } 1126 1127 static inline bool mutex_is_locked(struct mutex *) 1128 { 1129 return true; 1130 } 1131 1132 static inline bool signal_pending(void *) 1133 { 1134 return false; 1135 } 1136 1137 static inline bool is_file_hugepages(struct file *) 1138 { 1139 return false; 1140 } 1141 1142 static inline int security_vm_enough_memory_mm(struct mm_struct *, long) 1143 { 1144 return 0; 1145 } 1146 1147 static inline bool may_expand_vm(struct mm_struct *, vm_flags_t, unsigned long) 1148 { 1149 return true; 1150 } 1151 1152 static inline void vm_flags_init(struct vm_area_struct *vma, 1153 vm_flags_t flags) 1154 { 1155 vma->__vm_flags = flags; 1156 } 1157 1158 static inline void vm_flags_set(struct vm_area_struct *vma, 1159 vm_flags_t flags) 1160 { 1161 vma_start_write(vma); 1162 vma->__vm_flags |= flags; 1163 } 1164 1165 static inline void vm_flags_clear(struct vm_area_struct *vma, 1166 vm_flags_t flags) 1167 { 1168 vma_start_write(vma); 1169 vma->__vm_flags &= ~flags; 1170 } 1171 1172 static inline int shmem_zero_setup(struct vm_area_struct *) 1173 { 1174 return 0; 1175 } 1176 1177 static inline void vma_set_anonymous(struct vm_area_struct *vma) 1178 { 1179 vma->vm_ops = NULL; 1180 } 1181 1182 static inline void ksm_add_vma(struct vm_area_struct *) 1183 { 1184 } 1185 1186 static inline void perf_event_mmap(struct vm_area_struct *) 1187 { 1188 } 1189 1190 static inline bool vma_is_dax(struct vm_area_struct *) 1191 { 1192 return false; 1193 } 1194 1195 static inline struct vm_area_struct *get_gate_vma(struct mm_struct *) 1196 { 1197 return NULL; 1198 } 1199 1200 bool vma_wants_writenotify(struct vm_area_struct *vma, pgprot_t vm_page_prot); 1201 1202 /* Update vma->vm_page_prot to reflect vma->vm_flags. */ 1203 static inline void vma_set_page_prot(struct vm_area_struct *vma) 1204 { 1205 vm_flags_t vm_flags = vma->vm_flags; 1206 pgprot_t vm_page_prot; 1207 1208 /* testing: we inline vm_pgprot_modify() to avoid clash with vma.h. */ 1209 vm_page_prot = pgprot_modify(vma->vm_page_prot, vm_get_page_prot(vm_flags)); 1210 1211 if (vma_wants_writenotify(vma, vm_page_prot)) { 1212 vm_flags &= ~VM_SHARED; 1213 /* testing: we inline vm_pgprot_modify() to avoid clash with vma.h. */ 1214 vm_page_prot = pgprot_modify(vm_page_prot, vm_get_page_prot(vm_flags)); 1215 } 1216 /* remove_protection_ptes reads vma->vm_page_prot without mmap_lock */ 1217 WRITE_ONCE(vma->vm_page_prot, vm_page_prot); 1218 } 1219 1220 static inline bool arch_validate_flags(vm_flags_t) 1221 { 1222 return true; 1223 } 1224 1225 static inline void vma_close(struct vm_area_struct *) 1226 { 1227 } 1228 1229 static inline int mmap_file(struct file *, struct vm_area_struct *) 1230 { 1231 return 0; 1232 } 1233 1234 static inline unsigned long stack_guard_start_gap(struct vm_area_struct *vma) 1235 { 1236 if (vma->vm_flags & VM_GROWSDOWN) 1237 return stack_guard_gap; 1238 1239 /* See reasoning around the VM_SHADOW_STACK definition */ 1240 if (vma->vm_flags & VM_SHADOW_STACK) 1241 return PAGE_SIZE; 1242 1243 return 0; 1244 } 1245 1246 static inline unsigned long vm_start_gap(struct vm_area_struct *vma) 1247 { 1248 unsigned long gap = stack_guard_start_gap(vma); 1249 unsigned long vm_start = vma->vm_start; 1250 1251 vm_start -= gap; 1252 if (vm_start > vma->vm_start) 1253 vm_start = 0; 1254 return vm_start; 1255 } 1256 1257 static inline unsigned long vm_end_gap(struct vm_area_struct *vma) 1258 { 1259 unsigned long vm_end = vma->vm_end; 1260 1261 if (vma->vm_flags & VM_GROWSUP) { 1262 vm_end += stack_guard_gap; 1263 if (vm_end < vma->vm_end) 1264 vm_end = -PAGE_SIZE; 1265 } 1266 return vm_end; 1267 } 1268 1269 static inline int is_hugepage_only_range(struct mm_struct *mm, 1270 unsigned long addr, unsigned long len) 1271 { 1272 return 0; 1273 } 1274 1275 static inline bool vma_is_accessible(struct vm_area_struct *vma) 1276 { 1277 return vma->vm_flags & VM_ACCESS_FLAGS; 1278 } 1279 1280 static inline bool capable(int cap) 1281 { 1282 return true; 1283 } 1284 1285 static inline bool mlock_future_ok(struct mm_struct *mm, vm_flags_t vm_flags, 1286 unsigned long bytes) 1287 { 1288 unsigned long locked_pages, limit_pages; 1289 1290 if (!(vm_flags & VM_LOCKED) || capable(CAP_IPC_LOCK)) 1291 return true; 1292 1293 locked_pages = bytes >> PAGE_SHIFT; 1294 locked_pages += mm->locked_vm; 1295 1296 limit_pages = rlimit(RLIMIT_MEMLOCK); 1297 limit_pages >>= PAGE_SHIFT; 1298 1299 return locked_pages <= limit_pages; 1300 } 1301 1302 static inline int __anon_vma_prepare(struct vm_area_struct *vma) 1303 { 1304 struct anon_vma *anon_vma = calloc(1, sizeof(struct anon_vma)); 1305 1306 if (!anon_vma) 1307 return -ENOMEM; 1308 1309 anon_vma->root = anon_vma; 1310 vma->anon_vma = anon_vma; 1311 1312 return 0; 1313 } 1314 1315 static inline int anon_vma_prepare(struct vm_area_struct *vma) 1316 { 1317 if (likely(vma->anon_vma)) 1318 return 0; 1319 1320 return __anon_vma_prepare(vma); 1321 } 1322 1323 static inline void userfaultfd_unmap_complete(struct mm_struct *mm, 1324 struct list_head *uf) 1325 { 1326 } 1327 1328 /* 1329 * Denies creating a writable executable mapping or gaining executable permissions. 1330 * 1331 * This denies the following: 1332 * 1333 * a) mmap(PROT_WRITE | PROT_EXEC) 1334 * 1335 * b) mmap(PROT_WRITE) 1336 * mprotect(PROT_EXEC) 1337 * 1338 * c) mmap(PROT_WRITE) 1339 * mprotect(PROT_READ) 1340 * mprotect(PROT_EXEC) 1341 * 1342 * But allows the following: 1343 * 1344 * d) mmap(PROT_READ | PROT_EXEC) 1345 * mmap(PROT_READ | PROT_EXEC | PROT_BTI) 1346 * 1347 * This is only applicable if the user has set the Memory-Deny-Write-Execute 1348 * (MDWE) protection mask for the current process. 1349 * 1350 * @old specifies the VMA flags the VMA originally possessed, and @new the ones 1351 * we propose to set. 1352 * 1353 * Return: false if proposed change is OK, true if not ok and should be denied. 1354 */ 1355 static inline bool map_deny_write_exec(unsigned long old, unsigned long new) 1356 { 1357 /* If MDWE is disabled, we have nothing to deny. */ 1358 if (!test_bit(MMF_HAS_MDWE, ¤t->mm->flags)) 1359 return false; 1360 1361 /* If the new VMA is not executable, we have nothing to deny. */ 1362 if (!(new & VM_EXEC)) 1363 return false; 1364 1365 /* Under MDWE we do not accept newly writably executable VMAs... */ 1366 if (new & VM_WRITE) 1367 return true; 1368 1369 /* ...nor previously non-executable VMAs becoming executable. */ 1370 if (!(old & VM_EXEC)) 1371 return true; 1372 1373 return false; 1374 } 1375 1376 static inline int mapping_map_writable(struct address_space *mapping) 1377 { 1378 int c = atomic_read(&mapping->i_mmap_writable); 1379 1380 /* Derived from the raw_atomic_inc_unless_negative() implementation. */ 1381 do { 1382 if (c < 0) 1383 return -EPERM; 1384 } while (!__sync_bool_compare_and_swap(&mapping->i_mmap_writable, c, c+1)); 1385 1386 return 0; 1387 } 1388 1389 static inline unsigned long move_page_tables(struct pagetable_move_control *pmc) 1390 { 1391 (void)pmc; 1392 1393 return 0; 1394 } 1395 1396 static inline void free_pgd_range(struct mmu_gather *tlb, 1397 unsigned long addr, unsigned long end, 1398 unsigned long floor, unsigned long ceiling) 1399 { 1400 (void)tlb; 1401 (void)addr; 1402 (void)end; 1403 (void)floor; 1404 (void)ceiling; 1405 } 1406 1407 static inline int ksm_execve(struct mm_struct *mm) 1408 { 1409 (void)mm; 1410 1411 return 0; 1412 } 1413 1414 static inline void ksm_exit(struct mm_struct *mm) 1415 { 1416 (void)mm; 1417 } 1418 1419 static inline void vma_lock_init(struct vm_area_struct *vma, bool reset_refcnt) 1420 { 1421 (void)vma; 1422 (void)reset_refcnt; 1423 } 1424 1425 static inline void vma_numab_state_init(struct vm_area_struct *vma) 1426 { 1427 (void)vma; 1428 } 1429 1430 static inline void vma_numab_state_free(struct vm_area_struct *vma) 1431 { 1432 (void)vma; 1433 } 1434 1435 static inline void dup_anon_vma_name(struct vm_area_struct *orig_vma, 1436 struct vm_area_struct *new_vma) 1437 { 1438 (void)orig_vma; 1439 (void)new_vma; 1440 } 1441 1442 static inline void free_anon_vma_name(struct vm_area_struct *vma) 1443 { 1444 (void)vma; 1445 } 1446 1447 /* Declared in vma.h. */ 1448 static inline void set_vma_from_desc(struct vm_area_struct *vma, 1449 struct vm_area_desc *desc); 1450 1451 static inline struct vm_area_desc *vma_to_desc(struct vm_area_struct *vma, 1452 struct vm_area_desc *desc); 1453 1454 static int compat_vma_mmap_prepare(struct file *file, 1455 struct vm_area_struct *vma) 1456 { 1457 struct vm_area_desc desc; 1458 int err; 1459 1460 err = file->f_op->mmap_prepare(vma_to_desc(vma, &desc)); 1461 if (err) 1462 return err; 1463 set_vma_from_desc(vma, &desc); 1464 1465 return 0; 1466 } 1467 1468 /* Did the driver provide valid mmap hook configuration? */ 1469 static inline bool can_mmap_file(struct file *file) 1470 { 1471 bool has_mmap = file->f_op->mmap; 1472 bool has_mmap_prepare = file->f_op->mmap_prepare; 1473 1474 /* Hooks are mutually exclusive. */ 1475 if (WARN_ON_ONCE(has_mmap && has_mmap_prepare)) 1476 return false; 1477 if (!has_mmap && !has_mmap_prepare) 1478 return false; 1479 1480 return true; 1481 } 1482 1483 static inline int vfs_mmap(struct file *file, struct vm_area_struct *vma) 1484 { 1485 if (file->f_op->mmap_prepare) 1486 return compat_vma_mmap_prepare(file, vma); 1487 1488 return file->f_op->mmap(file, vma); 1489 } 1490 1491 static inline int vfs_mmap_prepare(struct file *file, struct vm_area_desc *desc) 1492 { 1493 return file->f_op->mmap_prepare(desc); 1494 } 1495 1496 static inline void fixup_hugetlb_reservations(struct vm_area_struct *vma) 1497 { 1498 (void)vma; 1499 } 1500 1501 static inline void vma_set_file(struct vm_area_struct *vma, struct file *file) 1502 { 1503 /* Changing an anonymous vma with this is illegal */ 1504 get_file(file); 1505 swap(vma->vm_file, file); 1506 fput(file); 1507 } 1508 1509 static inline bool shmem_file(struct file *) 1510 { 1511 return false; 1512 } 1513 1514 static inline vm_flags_t ksm_vma_flags(const struct mm_struct *, const struct file *, 1515 vm_flags_t vm_flags) 1516 { 1517 return vm_flags; 1518 } 1519 1520 #endif /* __MM_VMA_INTERNAL_H */ 1521