Root/
1 | /* |
2 | * linux/mm/mlock.c |
3 | * |
4 | * (C) Copyright 1995 Linus Torvalds |
5 | * (C) Copyright 2002 Christoph Hellwig |
6 | */ |
7 | |
8 | #include <linux/capability.h> |
9 | #include <linux/mman.h> |
10 | #include <linux/mm.h> |
11 | #include <linux/swap.h> |
12 | #include <linux/swapops.h> |
13 | #include <linux/pagemap.h> |
14 | #include <linux/mempolicy.h> |
15 | #include <linux/syscalls.h> |
16 | #include <linux/sched.h> |
17 | #include <linux/module.h> |
18 | #include <linux/rmap.h> |
19 | #include <linux/mmzone.h> |
20 | #include <linux/hugetlb.h> |
21 | |
22 | #include "internal.h" |
23 | |
24 | int can_do_mlock(void) |
25 | { |
26 | if (capable(CAP_IPC_LOCK)) |
27 | return 1; |
28 | if (rlimit(RLIMIT_MEMLOCK) != 0) |
29 | return 1; |
30 | return 0; |
31 | } |
32 | EXPORT_SYMBOL(can_do_mlock); |
33 | |
34 | /* |
35 | * Mlocked pages are marked with PageMlocked() flag for efficient testing |
36 | * in vmscan and, possibly, the fault path; and to support semi-accurate |
37 | * statistics. |
38 | * |
39 | * An mlocked page [PageMlocked(page)] is unevictable. As such, it will |
40 | * be placed on the LRU "unevictable" list, rather than the [in]active lists. |
41 | * The unevictable list is an LRU sibling list to the [in]active lists. |
42 | * PageUnevictable is set to indicate the unevictable state. |
43 | * |
44 | * When lazy mlocking via vmscan, it is important to ensure that the |
45 | * vma's VM_LOCKED status is not concurrently being modified, otherwise we |
46 | * may have mlocked a page that is being munlocked. So lazy mlock must take |
47 | * the mmap_sem for read, and verify that the vma really is locked |
48 | * (see mm/rmap.c). |
49 | */ |
50 | |
51 | /* |
52 | * LRU accounting for clear_page_mlock() |
53 | */ |
54 | void __clear_page_mlock(struct page *page) |
55 | { |
56 | VM_BUG_ON(!PageLocked(page)); |
57 | |
58 | if (!page->mapping) { /* truncated ? */ |
59 | return; |
60 | } |
61 | |
62 | dec_zone_page_state(page, NR_MLOCK); |
63 | count_vm_event(UNEVICTABLE_PGCLEARED); |
64 | if (!isolate_lru_page(page)) { |
65 | putback_lru_page(page); |
66 | } else { |
67 | /* |
68 | * We lost the race. the page already moved to evictable list. |
69 | */ |
70 | if (PageUnevictable(page)) |
71 | count_vm_event(UNEVICTABLE_PGSTRANDED); |
72 | } |
73 | } |
74 | |
75 | /* |
76 | * Mark page as mlocked if not already. |
77 | * If page on LRU, isolate and putback to move to unevictable list. |
78 | */ |
79 | void mlock_vma_page(struct page *page) |
80 | { |
81 | BUG_ON(!PageLocked(page)); |
82 | |
83 | if (!TestSetPageMlocked(page)) { |
84 | inc_zone_page_state(page, NR_MLOCK); |
85 | count_vm_event(UNEVICTABLE_PGMLOCKED); |
86 | if (!isolate_lru_page(page)) |
87 | putback_lru_page(page); |
88 | } |
89 | } |
90 | |
91 | /** |
92 | * munlock_vma_page - munlock a vma page |
93 | * @page - page to be unlocked |
94 | * |
95 | * called from munlock()/munmap() path with page supposedly on the LRU. |
96 | * When we munlock a page, because the vma where we found the page is being |
97 | * munlock()ed or munmap()ed, we want to check whether other vmas hold the |
98 | * page locked so that we can leave it on the unevictable lru list and not |
99 | * bother vmscan with it. However, to walk the page's rmap list in |
100 | * try_to_munlock() we must isolate the page from the LRU. If some other |
101 | * task has removed the page from the LRU, we won't be able to do that. |
102 | * So we clear the PageMlocked as we might not get another chance. If we |
103 | * can't isolate the page, we leave it for putback_lru_page() and vmscan |
104 | * [page_referenced()/try_to_unmap()] to deal with. |
105 | */ |
106 | void munlock_vma_page(struct page *page) |
107 | { |
108 | BUG_ON(!PageLocked(page)); |
109 | |
110 | if (TestClearPageMlocked(page)) { |
111 | dec_zone_page_state(page, NR_MLOCK); |
112 | if (!isolate_lru_page(page)) { |
113 | int ret = try_to_munlock(page); |
114 | /* |
115 | * did try_to_unlock() succeed or punt? |
116 | */ |
117 | if (ret != SWAP_MLOCK) |
118 | count_vm_event(UNEVICTABLE_PGMUNLOCKED); |
119 | |
120 | putback_lru_page(page); |
121 | } else { |
122 | /* |
123 | * Some other task has removed the page from the LRU. |
124 | * putback_lru_page() will take care of removing the |
125 | * page from the unevictable list, if necessary. |
126 | * vmscan [page_referenced()] will move the page back |
127 | * to the unevictable list if some other vma has it |
128 | * mlocked. |
129 | */ |
130 | if (PageUnevictable(page)) |
131 | count_vm_event(UNEVICTABLE_PGSTRANDED); |
132 | else |
133 | count_vm_event(UNEVICTABLE_PGMUNLOCKED); |
134 | } |
135 | } |
136 | } |
137 | |
138 | /** |
139 | * __mlock_vma_pages_range() - mlock a range of pages in the vma. |
140 | * @vma: target vma |
141 | * @start: start address |
142 | * @end: end address |
143 | * |
144 | * This takes care of making the pages present too. |
145 | * |
146 | * return 0 on success, negative error code on error. |
147 | * |
148 | * vma->vm_mm->mmap_sem must be held for at least read. |
149 | */ |
150 | static long __mlock_vma_pages_range(struct vm_area_struct *vma, |
151 | unsigned long start, unsigned long end) |
152 | { |
153 | struct mm_struct *mm = vma->vm_mm; |
154 | unsigned long addr = start; |
155 | struct page *pages[16]; /* 16 gives a reasonable batch */ |
156 | int nr_pages = (end - start) / PAGE_SIZE; |
157 | int ret = 0; |
158 | int gup_flags; |
159 | |
160 | VM_BUG_ON(start & ~PAGE_MASK); |
161 | VM_BUG_ON(end & ~PAGE_MASK); |
162 | VM_BUG_ON(start < vma->vm_start); |
163 | VM_BUG_ON(end > vma->vm_end); |
164 | VM_BUG_ON(!rwsem_is_locked(&mm->mmap_sem)); |
165 | |
166 | gup_flags = FOLL_TOUCH | FOLL_GET; |
167 | if (vma->vm_flags & VM_WRITE) |
168 | gup_flags |= FOLL_WRITE; |
169 | |
170 | while (nr_pages > 0) { |
171 | int i; |
172 | |
173 | cond_resched(); |
174 | |
175 | /* |
176 | * get_user_pages makes pages present if we are |
177 | * setting mlock. and this extra reference count will |
178 | * disable migration of this page. However, page may |
179 | * still be truncated out from under us. |
180 | */ |
181 | ret = __get_user_pages(current, mm, addr, |
182 | min_t(int, nr_pages, ARRAY_SIZE(pages)), |
183 | gup_flags, pages, NULL); |
184 | /* |
185 | * This can happen for, e.g., VM_NONLINEAR regions before |
186 | * a page has been allocated and mapped at a given offset, |
187 | * or for addresses that map beyond end of a file. |
188 | * We'll mlock the pages if/when they get faulted in. |
189 | */ |
190 | if (ret < 0) |
191 | break; |
192 | |
193 | lru_add_drain(); /* push cached pages to LRU */ |
194 | |
195 | for (i = 0; i < ret; i++) { |
196 | struct page *page = pages[i]; |
197 | |
198 | if (page->mapping) { |
199 | /* |
200 | * That preliminary check is mainly to avoid |
201 | * the pointless overhead of lock_page on the |
202 | * ZERO_PAGE: which might bounce very badly if |
203 | * there is contention. However, we're still |
204 | * dirtying its cacheline with get/put_page: |
205 | * we'll add another __get_user_pages flag to |
206 | * avoid it if that case turns out to matter. |
207 | */ |
208 | lock_page(page); |
209 | /* |
210 | * Because we lock page here and migration is |
211 | * blocked by the elevated reference, we need |
212 | * only check for file-cache page truncation. |
213 | */ |
214 | if (page->mapping) |
215 | mlock_vma_page(page); |
216 | unlock_page(page); |
217 | } |
218 | put_page(page); /* ref from get_user_pages() */ |
219 | } |
220 | |
221 | addr += ret * PAGE_SIZE; |
222 | nr_pages -= ret; |
223 | ret = 0; |
224 | } |
225 | |
226 | return ret; /* 0 or negative error code */ |
227 | } |
228 | |
229 | /* |
230 | * convert get_user_pages() return value to posix mlock() error |
231 | */ |
232 | static int __mlock_posix_error_return(long retval) |
233 | { |
234 | if (retval == -EFAULT) |
235 | retval = -ENOMEM; |
236 | else if (retval == -ENOMEM) |
237 | retval = -EAGAIN; |
238 | return retval; |
239 | } |
240 | |
241 | /** |
242 | * mlock_vma_pages_range() - mlock pages in specified vma range. |
243 | * @vma - the vma containing the specfied address range |
244 | * @start - starting address in @vma to mlock |
245 | * @end - end address [+1] in @vma to mlock |
246 | * |
247 | * For mmap()/mremap()/expansion of mlocked vma. |
248 | * |
249 | * return 0 on success for "normal" vmas. |
250 | * |
251 | * return number of pages [> 0] to be removed from locked_vm on success |
252 | * of "special" vmas. |
253 | */ |
254 | long mlock_vma_pages_range(struct vm_area_struct *vma, |
255 | unsigned long start, unsigned long end) |
256 | { |
257 | int nr_pages = (end - start) / PAGE_SIZE; |
258 | BUG_ON(!(vma->vm_flags & VM_LOCKED)); |
259 | |
260 | /* |
261 | * filter unlockable vmas |
262 | */ |
263 | if (vma->vm_flags & (VM_IO | VM_PFNMAP)) |
264 | goto no_mlock; |
265 | |
266 | if (!((vma->vm_flags & (VM_DONTEXPAND | VM_RESERVED)) || |
267 | is_vm_hugetlb_page(vma) || |
268 | vma == get_gate_vma(current))) { |
269 | |
270 | __mlock_vma_pages_range(vma, start, end); |
271 | |
272 | /* Hide errors from mmap() and other callers */ |
273 | return 0; |
274 | } |
275 | |
276 | /* |
277 | * User mapped kernel pages or huge pages: |
278 | * make these pages present to populate the ptes, but |
279 | * fall thru' to reset VM_LOCKED--no need to unlock, and |
280 | * return nr_pages so these don't get counted against task's |
281 | * locked limit. huge pages are already counted against |
282 | * locked vm limit. |
283 | */ |
284 | make_pages_present(start, end); |
285 | |
286 | no_mlock: |
287 | vma->vm_flags &= ~VM_LOCKED; /* and don't come back! */ |
288 | return nr_pages; /* error or pages NOT mlocked */ |
289 | } |
290 | |
291 | /* |
292 | * munlock_vma_pages_range() - munlock all pages in the vma range.' |
293 | * @vma - vma containing range to be munlock()ed. |
294 | * @start - start address in @vma of the range |
295 | * @end - end of range in @vma. |
296 | * |
297 | * For mremap(), munmap() and exit(). |
298 | * |
299 | * Called with @vma VM_LOCKED. |
300 | * |
301 | * Returns with VM_LOCKED cleared. Callers must be prepared to |
302 | * deal with this. |
303 | * |
304 | * We don't save and restore VM_LOCKED here because pages are |
305 | * still on lru. In unmap path, pages might be scanned by reclaim |
306 | * and re-mlocked by try_to_{munlock|unmap} before we unmap and |
307 | * free them. This will result in freeing mlocked pages. |
308 | */ |
309 | void munlock_vma_pages_range(struct vm_area_struct *vma, |
310 | unsigned long start, unsigned long end) |
311 | { |
312 | unsigned long addr; |
313 | |
314 | lru_add_drain(); |
315 | vma->vm_flags &= ~VM_LOCKED; |
316 | |
317 | for (addr = start; addr < end; addr += PAGE_SIZE) { |
318 | struct page *page; |
319 | /* |
320 | * Although FOLL_DUMP is intended for get_dump_page(), |
321 | * it just so happens that its special treatment of the |
322 | * ZERO_PAGE (returning an error instead of doing get_page) |
323 | * suits munlock very well (and if somehow an abnormal page |
324 | * has sneaked into the range, we won't oops here: great). |
325 | */ |
326 | page = follow_page(vma, addr, FOLL_GET | FOLL_DUMP); |
327 | if (page && !IS_ERR(page)) { |
328 | lock_page(page); |
329 | /* |
330 | * Like in __mlock_vma_pages_range(), |
331 | * because we lock page here and migration is |
332 | * blocked by the elevated reference, we need |
333 | * only check for file-cache page truncation. |
334 | */ |
335 | if (page->mapping) |
336 | munlock_vma_page(page); |
337 | unlock_page(page); |
338 | put_page(page); |
339 | } |
340 | cond_resched(); |
341 | } |
342 | } |
343 | |
344 | /* |
345 | * mlock_fixup - handle mlock[all]/munlock[all] requests. |
346 | * |
347 | * Filters out "special" vmas -- VM_LOCKED never gets set for these, and |
348 | * munlock is a no-op. However, for some special vmas, we go ahead and |
349 | * populate the ptes via make_pages_present(). |
350 | * |
351 | * For vmas that pass the filters, merge/split as appropriate. |
352 | */ |
353 | static int mlock_fixup(struct vm_area_struct *vma, struct vm_area_struct **prev, |
354 | unsigned long start, unsigned long end, unsigned int newflags) |
355 | { |
356 | struct mm_struct *mm = vma->vm_mm; |
357 | pgoff_t pgoff; |
358 | int nr_pages; |
359 | int ret = 0; |
360 | int lock = newflags & VM_LOCKED; |
361 | |
362 | if (newflags == vma->vm_flags || |
363 | (vma->vm_flags & (VM_IO | VM_PFNMAP))) |
364 | goto out; /* don't set VM_LOCKED, don't count */ |
365 | |
366 | if ((vma->vm_flags & (VM_DONTEXPAND | VM_RESERVED)) || |
367 | is_vm_hugetlb_page(vma) || |
368 | vma == get_gate_vma(current)) { |
369 | if (lock) |
370 | make_pages_present(start, end); |
371 | goto out; /* don't set VM_LOCKED, don't count */ |
372 | } |
373 | |
374 | pgoff = vma->vm_pgoff + ((start - vma->vm_start) >> PAGE_SHIFT); |
375 | *prev = vma_merge(mm, *prev, start, end, newflags, vma->anon_vma, |
376 | vma->vm_file, pgoff, vma_policy(vma)); |
377 | if (*prev) { |
378 | vma = *prev; |
379 | goto success; |
380 | } |
381 | |
382 | if (start != vma->vm_start) { |
383 | ret = split_vma(mm, vma, start, 1); |
384 | if (ret) |
385 | goto out; |
386 | } |
387 | |
388 | if (end != vma->vm_end) { |
389 | ret = split_vma(mm, vma, end, 0); |
390 | if (ret) |
391 | goto out; |
392 | } |
393 | |
394 | success: |
395 | /* |
396 | * Keep track of amount of locked VM. |
397 | */ |
398 | nr_pages = (end - start) >> PAGE_SHIFT; |
399 | if (!lock) |
400 | nr_pages = -nr_pages; |
401 | mm->locked_vm += nr_pages; |
402 | |
403 | /* |
404 | * vm_flags is protected by the mmap_sem held in write mode. |
405 | * It's okay if try_to_unmap_one unmaps a page just after we |
406 | * set VM_LOCKED, __mlock_vma_pages_range will bring it back. |
407 | */ |
408 | |
409 | if (lock) { |
410 | vma->vm_flags = newflags; |
411 | ret = __mlock_vma_pages_range(vma, start, end); |
412 | if (ret < 0) |
413 | ret = __mlock_posix_error_return(ret); |
414 | } else { |
415 | munlock_vma_pages_range(vma, start, end); |
416 | } |
417 | |
418 | out: |
419 | *prev = vma; |
420 | return ret; |
421 | } |
422 | |
423 | static int do_mlock(unsigned long start, size_t len, int on) |
424 | { |
425 | unsigned long nstart, end, tmp; |
426 | struct vm_area_struct * vma, * prev; |
427 | int error; |
428 | |
429 | len = PAGE_ALIGN(len); |
430 | end = start + len; |
431 | if (end < start) |
432 | return -EINVAL; |
433 | if (end == start) |
434 | return 0; |
435 | vma = find_vma_prev(current->mm, start, &prev); |
436 | if (!vma || vma->vm_start > start) |
437 | return -ENOMEM; |
438 | |
439 | if (start > vma->vm_start) |
440 | prev = vma; |
441 | |
442 | for (nstart = start ; ; ) { |
443 | unsigned int newflags; |
444 | |
445 | /* Here we know that vma->vm_start <= nstart < vma->vm_end. */ |
446 | |
447 | newflags = vma->vm_flags | VM_LOCKED; |
448 | if (!on) |
449 | newflags &= ~VM_LOCKED; |
450 | |
451 | tmp = vma->vm_end; |
452 | if (tmp > end) |
453 | tmp = end; |
454 | error = mlock_fixup(vma, &prev, nstart, tmp, newflags); |
455 | if (error) |
456 | break; |
457 | nstart = tmp; |
458 | if (nstart < prev->vm_end) |
459 | nstart = prev->vm_end; |
460 | if (nstart >= end) |
461 | break; |
462 | |
463 | vma = prev->vm_next; |
464 | if (!vma || vma->vm_start != nstart) { |
465 | error = -ENOMEM; |
466 | break; |
467 | } |
468 | } |
469 | return error; |
470 | } |
471 | |
472 | SYSCALL_DEFINE2(mlock, unsigned long, start, size_t, len) |
473 | { |
474 | unsigned long locked; |
475 | unsigned long lock_limit; |
476 | int error = -ENOMEM; |
477 | |
478 | if (!can_do_mlock()) |
479 | return -EPERM; |
480 | |
481 | lru_add_drain_all(); /* flush pagevec */ |
482 | |
483 | down_write(¤t->mm->mmap_sem); |
484 | len = PAGE_ALIGN(len + (start & ~PAGE_MASK)); |
485 | start &= PAGE_MASK; |
486 | |
487 | locked = len >> PAGE_SHIFT; |
488 | locked += current->mm->locked_vm; |
489 | |
490 | lock_limit = rlimit(RLIMIT_MEMLOCK); |
491 | lock_limit >>= PAGE_SHIFT; |
492 | |
493 | /* check against resource limits */ |
494 | if ((locked <= lock_limit) || capable(CAP_IPC_LOCK)) |
495 | error = do_mlock(start, len, 1); |
496 | up_write(¤t->mm->mmap_sem); |
497 | return error; |
498 | } |
499 | |
500 | SYSCALL_DEFINE2(munlock, unsigned long, start, size_t, len) |
501 | { |
502 | int ret; |
503 | |
504 | down_write(¤t->mm->mmap_sem); |
505 | len = PAGE_ALIGN(len + (start & ~PAGE_MASK)); |
506 | start &= PAGE_MASK; |
507 | ret = do_mlock(start, len, 0); |
508 | up_write(¤t->mm->mmap_sem); |
509 | return ret; |
510 | } |
511 | |
512 | static int do_mlockall(int flags) |
513 | { |
514 | struct vm_area_struct * vma, * prev = NULL; |
515 | unsigned int def_flags = 0; |
516 | |
517 | if (flags & MCL_FUTURE) |
518 | def_flags = VM_LOCKED; |
519 | current->mm->def_flags = def_flags; |
520 | if (flags == MCL_FUTURE) |
521 | goto out; |
522 | |
523 | for (vma = current->mm->mmap; vma ; vma = prev->vm_next) { |
524 | unsigned int newflags; |
525 | |
526 | newflags = vma->vm_flags | VM_LOCKED; |
527 | if (!(flags & MCL_CURRENT)) |
528 | newflags &= ~VM_LOCKED; |
529 | |
530 | /* Ignore errors */ |
531 | mlock_fixup(vma, &prev, vma->vm_start, vma->vm_end, newflags); |
532 | } |
533 | out: |
534 | return 0; |
535 | } |
536 | |
537 | SYSCALL_DEFINE1(mlockall, int, flags) |
538 | { |
539 | unsigned long lock_limit; |
540 | int ret = -EINVAL; |
541 | |
542 | if (!flags || (flags & ~(MCL_CURRENT | MCL_FUTURE))) |
543 | goto out; |
544 | |
545 | ret = -EPERM; |
546 | if (!can_do_mlock()) |
547 | goto out; |
548 | |
549 | lru_add_drain_all(); /* flush pagevec */ |
550 | |
551 | down_write(¤t->mm->mmap_sem); |
552 | |
553 | lock_limit = rlimit(RLIMIT_MEMLOCK); |
554 | lock_limit >>= PAGE_SHIFT; |
555 | |
556 | ret = -ENOMEM; |
557 | if (!(flags & MCL_CURRENT) || (current->mm->total_vm <= lock_limit) || |
558 | capable(CAP_IPC_LOCK)) |
559 | ret = do_mlockall(flags); |
560 | up_write(¤t->mm->mmap_sem); |
561 | out: |
562 | return ret; |
563 | } |
564 | |
565 | SYSCALL_DEFINE0(munlockall) |
566 | { |
567 | int ret; |
568 | |
569 | down_write(¤t->mm->mmap_sem); |
570 | ret = do_mlockall(0); |
571 | up_write(¤t->mm->mmap_sem); |
572 | return ret; |
573 | } |
574 | |
575 | /* |
576 | * Objects with different lifetime than processes (SHM_LOCK and SHM_HUGETLB |
577 | * shm segments) get accounted against the user_struct instead. |
578 | */ |
579 | static DEFINE_SPINLOCK(shmlock_user_lock); |
580 | |
581 | int user_shm_lock(size_t size, struct user_struct *user) |
582 | { |
583 | unsigned long lock_limit, locked; |
584 | int allowed = 0; |
585 | |
586 | locked = (size + PAGE_SIZE - 1) >> PAGE_SHIFT; |
587 | lock_limit = rlimit(RLIMIT_MEMLOCK); |
588 | if (lock_limit == RLIM_INFINITY) |
589 | allowed = 1; |
590 | lock_limit >>= PAGE_SHIFT; |
591 | spin_lock(&shmlock_user_lock); |
592 | if (!allowed && |
593 | locked + user->locked_shm > lock_limit && !capable(CAP_IPC_LOCK)) |
594 | goto out; |
595 | get_uid(user); |
596 | user->locked_shm += locked; |
597 | allowed = 1; |
598 | out: |
599 | spin_unlock(&shmlock_user_lock); |
600 | return allowed; |
601 | } |
602 | |
603 | void user_shm_unlock(size_t size, struct user_struct *user) |
604 | { |
605 | spin_lock(&shmlock_user_lock); |
606 | user->locked_shm -= (size + PAGE_SIZE - 1) >> PAGE_SHIFT; |
607 | spin_unlock(&shmlock_user_lock); |
608 | free_uid(user); |
609 | } |
610 | |
611 | int account_locked_memory(struct mm_struct *mm, struct rlimit *rlim, |
612 | size_t size) |
613 | { |
614 | unsigned long lim, vm, pgsz; |
615 | int error = -ENOMEM; |
616 | |
617 | pgsz = PAGE_ALIGN(size) >> PAGE_SHIFT; |
618 | |
619 | down_write(&mm->mmap_sem); |
620 | |
621 | lim = ACCESS_ONCE(rlim[RLIMIT_AS].rlim_cur) >> PAGE_SHIFT; |
622 | vm = mm->total_vm + pgsz; |
623 | if (lim < vm) |
624 | goto out; |
625 | |
626 | lim = ACCESS_ONCE(rlim[RLIMIT_MEMLOCK].rlim_cur) >> PAGE_SHIFT; |
627 | vm = mm->locked_vm + pgsz; |
628 | if (lim < vm) |
629 | goto out; |
630 | |
631 | mm->total_vm += pgsz; |
632 | mm->locked_vm += pgsz; |
633 | |
634 | error = 0; |
635 | out: |
636 | up_write(&mm->mmap_sem); |
637 | return error; |
638 | } |
639 | |
640 | void refund_locked_memory(struct mm_struct *mm, size_t size) |
641 | { |
642 | unsigned long pgsz = PAGE_ALIGN(size) >> PAGE_SHIFT; |
643 | |
644 | down_write(&mm->mmap_sem); |
645 | |
646 | mm->total_vm -= pgsz; |
647 | mm->locked_vm -= pgsz; |
648 | |
649 | up_write(&mm->mmap_sem); |
650 | } |
651 |
Branches:
ben-wpan
ben-wpan-stefan
javiroman/ks7010
jz-2.6.34
jz-2.6.34-rc5
jz-2.6.34-rc6
jz-2.6.34-rc7
jz-2.6.35
jz-2.6.36
jz-2.6.37
jz-2.6.38
jz-2.6.39
jz-3.0
jz-3.1
jz-3.11
jz-3.12
jz-3.13
jz-3.15
jz-3.16
jz-3.18-dt
jz-3.2
jz-3.3
jz-3.4
jz-3.5
jz-3.6
jz-3.6-rc2-pwm
jz-3.9
jz-3.9-clk
jz-3.9-rc8
jz47xx
jz47xx-2.6.38
master
Tags:
od-2011-09-04
od-2011-09-18
v2.6.34-rc5
v2.6.34-rc6
v2.6.34-rc7
v3.9