Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * mm/mremap.c | |
3 | * | |
4 | * (C) Copyright 1996 Linus Torvalds | |
5 | * | |
046c6884 | 6 | * Address space accounting code <alan@lxorguk.ukuu.org.uk> |
1da177e4 LT |
7 | * (C) Copyright 2002 Red Hat Inc, All Rights Reserved |
8 | */ | |
9 | ||
10 | #include <linux/mm.h> | |
11 | #include <linux/hugetlb.h> | |
1da177e4 | 12 | #include <linux/shm.h> |
1ff82995 | 13 | #include <linux/ksm.h> |
1da177e4 LT |
14 | #include <linux/mman.h> |
15 | #include <linux/swap.h> | |
c59ede7b | 16 | #include <linux/capability.h> |
1da177e4 LT |
17 | #include <linux/fs.h> |
18 | #include <linux/highmem.h> | |
19 | #include <linux/security.h> | |
20 | #include <linux/syscalls.h> | |
cddb8a5c | 21 | #include <linux/mmu_notifier.h> |
1da177e4 LT |
22 | |
23 | #include <asm/uaccess.h> | |
24 | #include <asm/cacheflush.h> | |
25 | #include <asm/tlbflush.h> | |
26 | ||
ba470de4 RR |
27 | #include "internal.h" |
28 | ||
7be7a546 | 29 | static pmd_t *get_old_pmd(struct mm_struct *mm, unsigned long addr) |
1da177e4 LT |
30 | { |
31 | pgd_t *pgd; | |
32 | pud_t *pud; | |
33 | pmd_t *pmd; | |
34 | ||
35 | pgd = pgd_offset(mm, addr); | |
36 | if (pgd_none_or_clear_bad(pgd)) | |
37 | return NULL; | |
38 | ||
39 | pud = pud_offset(pgd, addr); | |
40 | if (pud_none_or_clear_bad(pud)) | |
41 | return NULL; | |
42 | ||
43 | pmd = pmd_offset(pud, addr); | |
bae9c19b | 44 | split_huge_page_pmd(mm, pmd); |
1da177e4 LT |
45 | if (pmd_none_or_clear_bad(pmd)) |
46 | return NULL; | |
47 | ||
7be7a546 | 48 | return pmd; |
1da177e4 LT |
49 | } |
50 | ||
8ac1f832 AA |
51 | static pmd_t *alloc_new_pmd(struct mm_struct *mm, struct vm_area_struct *vma, |
52 | unsigned long addr) | |
1da177e4 LT |
53 | { |
54 | pgd_t *pgd; | |
55 | pud_t *pud; | |
c74df32c | 56 | pmd_t *pmd; |
1da177e4 LT |
57 | |
58 | pgd = pgd_offset(mm, addr); | |
1da177e4 LT |
59 | pud = pud_alloc(mm, pgd, addr); |
60 | if (!pud) | |
c74df32c | 61 | return NULL; |
7be7a546 | 62 | |
1da177e4 | 63 | pmd = pmd_alloc(mm, pud, addr); |
7be7a546 | 64 | if (!pmd) |
c74df32c | 65 | return NULL; |
7be7a546 | 66 | |
8ac1f832 AA |
67 | VM_BUG_ON(pmd_trans_huge(*pmd)); |
68 | if (pmd_none(*pmd) && __pte_alloc(mm, vma, pmd, addr)) | |
c74df32c HD |
69 | return NULL; |
70 | ||
7be7a546 | 71 | return pmd; |
1da177e4 LT |
72 | } |
73 | ||
7be7a546 HD |
74 | static void move_ptes(struct vm_area_struct *vma, pmd_t *old_pmd, |
75 | unsigned long old_addr, unsigned long old_end, | |
76 | struct vm_area_struct *new_vma, pmd_t *new_pmd, | |
77 | unsigned long new_addr) | |
1da177e4 LT |
78 | { |
79 | struct address_space *mapping = NULL; | |
80 | struct mm_struct *mm = vma->vm_mm; | |
7be7a546 | 81 | pte_t *old_pte, *new_pte, pte; |
4c21e2f2 | 82 | spinlock_t *old_ptl, *new_ptl; |
cddb8a5c | 83 | unsigned long old_start; |
1da177e4 | 84 | |
cddb8a5c AA |
85 | old_start = old_addr; |
86 | mmu_notifier_invalidate_range_start(vma->vm_mm, | |
87 | old_start, old_end); | |
1da177e4 LT |
88 | if (vma->vm_file) { |
89 | /* | |
90 | * Subtle point from Rajesh Venkatasubramanian: before | |
25d9e2d1 | 91 | * moving file-based ptes, we must lock truncate_pagecache |
92 | * out, since it might clean the dst vma before the src vma, | |
1da177e4 LT |
93 | * and we propagate stale pages into the dst afterward. |
94 | */ | |
95 | mapping = vma->vm_file->f_mapping; | |
96 | spin_lock(&mapping->i_mmap_lock); | |
a3e8cc64 | 97 | new_vma->vm_truncate_count = 0; |
1da177e4 | 98 | } |
1da177e4 | 99 | |
4c21e2f2 HD |
100 | /* |
101 | * We don't have to worry about the ordering of src and dst | |
102 | * pte locks because exclusive mmap_sem prevents deadlock. | |
103 | */ | |
c74df32c | 104 | old_pte = pte_offset_map_lock(mm, old_pmd, old_addr, &old_ptl); |
ece0e2b6 | 105 | new_pte = pte_offset_map(new_pmd, new_addr); |
4c21e2f2 HD |
106 | new_ptl = pte_lockptr(mm, new_pmd); |
107 | if (new_ptl != old_ptl) | |
f20dc5f7 | 108 | spin_lock_nested(new_ptl, SINGLE_DEPTH_NESTING); |
6606c3e0 | 109 | arch_enter_lazy_mmu_mode(); |
7be7a546 HD |
110 | |
111 | for (; old_addr < old_end; old_pte++, old_addr += PAGE_SIZE, | |
112 | new_pte++, new_addr += PAGE_SIZE) { | |
113 | if (pte_none(*old_pte)) | |
114 | continue; | |
115 | pte = ptep_clear_flush(vma, old_addr, old_pte); | |
7be7a546 HD |
116 | pte = move_pte(pte, new_vma->vm_page_prot, old_addr, new_addr); |
117 | set_pte_at(mm, new_addr, new_pte, pte); | |
1da177e4 | 118 | } |
7be7a546 | 119 | |
6606c3e0 | 120 | arch_leave_lazy_mmu_mode(); |
4c21e2f2 HD |
121 | if (new_ptl != old_ptl) |
122 | spin_unlock(new_ptl); | |
ece0e2b6 | 123 | pte_unmap(new_pte - 1); |
c74df32c | 124 | pte_unmap_unlock(old_pte - 1, old_ptl); |
1da177e4 LT |
125 | if (mapping) |
126 | spin_unlock(&mapping->i_mmap_lock); | |
cddb8a5c | 127 | mmu_notifier_invalidate_range_end(vma->vm_mm, old_start, old_end); |
1da177e4 LT |
128 | } |
129 | ||
7be7a546 HD |
130 | #define LATENCY_LIMIT (64 * PAGE_SIZE) |
131 | ||
b6a2fea3 | 132 | unsigned long move_page_tables(struct vm_area_struct *vma, |
1da177e4 LT |
133 | unsigned long old_addr, struct vm_area_struct *new_vma, |
134 | unsigned long new_addr, unsigned long len) | |
135 | { | |
7be7a546 HD |
136 | unsigned long extent, next, old_end; |
137 | pmd_t *old_pmd, *new_pmd; | |
1da177e4 | 138 | |
7be7a546 HD |
139 | old_end = old_addr + len; |
140 | flush_cache_range(vma, old_addr, old_end); | |
1da177e4 | 141 | |
7be7a546 | 142 | for (; old_addr < old_end; old_addr += extent, new_addr += extent) { |
1da177e4 | 143 | cond_resched(); |
7be7a546 HD |
144 | next = (old_addr + PMD_SIZE) & PMD_MASK; |
145 | if (next - 1 > old_end) | |
146 | next = old_end; | |
147 | extent = next - old_addr; | |
148 | old_pmd = get_old_pmd(vma->vm_mm, old_addr); | |
149 | if (!old_pmd) | |
150 | continue; | |
8ac1f832 | 151 | new_pmd = alloc_new_pmd(vma->vm_mm, vma, new_addr); |
7be7a546 HD |
152 | if (!new_pmd) |
153 | break; | |
154 | next = (new_addr + PMD_SIZE) & PMD_MASK; | |
155 | if (extent > next - new_addr) | |
156 | extent = next - new_addr; | |
157 | if (extent > LATENCY_LIMIT) | |
158 | extent = LATENCY_LIMIT; | |
159 | move_ptes(vma, old_pmd, old_addr, old_addr + extent, | |
160 | new_vma, new_pmd, new_addr); | |
1da177e4 | 161 | } |
7be7a546 HD |
162 | |
163 | return len + old_addr - old_end; /* how much done */ | |
1da177e4 LT |
164 | } |
165 | ||
166 | static unsigned long move_vma(struct vm_area_struct *vma, | |
167 | unsigned long old_addr, unsigned long old_len, | |
168 | unsigned long new_len, unsigned long new_addr) | |
169 | { | |
170 | struct mm_struct *mm = vma->vm_mm; | |
171 | struct vm_area_struct *new_vma; | |
172 | unsigned long vm_flags = vma->vm_flags; | |
173 | unsigned long new_pgoff; | |
174 | unsigned long moved_len; | |
175 | unsigned long excess = 0; | |
365e9c87 | 176 | unsigned long hiwater_vm; |
1da177e4 | 177 | int split = 0; |
7103ad32 | 178 | int err; |
1da177e4 LT |
179 | |
180 | /* | |
181 | * We'd prefer to avoid failure later on in do_munmap: | |
182 | * which may split one vma into three before unmapping. | |
183 | */ | |
184 | if (mm->map_count >= sysctl_max_map_count - 3) | |
185 | return -ENOMEM; | |
186 | ||
1ff82995 HD |
187 | /* |
188 | * Advise KSM to break any KSM pages in the area to be moved: | |
189 | * it would be confusing if they were to turn up at the new | |
190 | * location, where they happen to coincide with different KSM | |
191 | * pages recently unmapped. But leave vma->vm_flags as it was, | |
192 | * so KSM can come around to merge on vma and new_vma afterwards. | |
193 | */ | |
7103ad32 HD |
194 | err = ksm_madvise(vma, old_addr, old_addr + old_len, |
195 | MADV_UNMERGEABLE, &vm_flags); | |
196 | if (err) | |
197 | return err; | |
1ff82995 | 198 | |
1da177e4 LT |
199 | new_pgoff = vma->vm_pgoff + ((old_addr - vma->vm_start) >> PAGE_SHIFT); |
200 | new_vma = copy_vma(&vma, new_addr, new_len, new_pgoff); | |
201 | if (!new_vma) | |
202 | return -ENOMEM; | |
203 | ||
204 | moved_len = move_page_tables(vma, old_addr, new_vma, new_addr, old_len); | |
205 | if (moved_len < old_len) { | |
206 | /* | |
207 | * On error, move entries back from new area to old, | |
208 | * which will succeed since page tables still there, | |
209 | * and then proceed to unmap new area instead of old. | |
210 | */ | |
211 | move_page_tables(new_vma, new_addr, vma, old_addr, moved_len); | |
212 | vma = new_vma; | |
213 | old_len = new_len; | |
214 | old_addr = new_addr; | |
215 | new_addr = -ENOMEM; | |
216 | } | |
217 | ||
218 | /* Conceal VM_ACCOUNT so old reservation is not undone */ | |
219 | if (vm_flags & VM_ACCOUNT) { | |
220 | vma->vm_flags &= ~VM_ACCOUNT; | |
221 | excess = vma->vm_end - vma->vm_start - old_len; | |
222 | if (old_addr > vma->vm_start && | |
223 | old_addr + old_len < vma->vm_end) | |
224 | split = 1; | |
225 | } | |
226 | ||
71799062 | 227 | /* |
365e9c87 HD |
228 | * If we failed to move page tables we still do total_vm increment |
229 | * since do_munmap() will decrement it by old_len == new_len. | |
230 | * | |
231 | * Since total_vm is about to be raised artificially high for a | |
232 | * moment, we need to restore high watermark afterwards: if stats | |
233 | * are taken meanwhile, total_vm and hiwater_vm appear too high. | |
234 | * If this were a serious issue, we'd add a flag to do_munmap(). | |
71799062 | 235 | */ |
365e9c87 | 236 | hiwater_vm = mm->hiwater_vm; |
71799062 | 237 | mm->total_vm += new_len >> PAGE_SHIFT; |
ab50b8ed | 238 | vm_stat_account(mm, vma->vm_flags, vma->vm_file, new_len>>PAGE_SHIFT); |
71799062 | 239 | |
1da177e4 LT |
240 | if (do_munmap(mm, old_addr, old_len) < 0) { |
241 | /* OOM: unable to split vma, just get accounts right */ | |
242 | vm_unacct_memory(excess >> PAGE_SHIFT); | |
243 | excess = 0; | |
244 | } | |
365e9c87 | 245 | mm->hiwater_vm = hiwater_vm; |
1da177e4 LT |
246 | |
247 | /* Restore VM_ACCOUNT if one or two pieces of vma left */ | |
248 | if (excess) { | |
249 | vma->vm_flags |= VM_ACCOUNT; | |
250 | if (split) | |
251 | vma->vm_next->vm_flags |= VM_ACCOUNT; | |
252 | } | |
253 | ||
1da177e4 LT |
254 | if (vm_flags & VM_LOCKED) { |
255 | mm->locked_vm += new_len >> PAGE_SHIFT; | |
256 | if (new_len > old_len) | |
ba470de4 RR |
257 | mlock_vma_pages_range(new_vma, new_addr + old_len, |
258 | new_addr + new_len); | |
1da177e4 LT |
259 | } |
260 | ||
261 | return new_addr; | |
262 | } | |
263 | ||
54f5de70 AV |
264 | static struct vm_area_struct *vma_to_resize(unsigned long addr, |
265 | unsigned long old_len, unsigned long new_len, unsigned long *p) | |
266 | { | |
267 | struct mm_struct *mm = current->mm; | |
268 | struct vm_area_struct *vma = find_vma(mm, addr); | |
269 | ||
270 | if (!vma || vma->vm_start > addr) | |
271 | goto Efault; | |
272 | ||
273 | if (is_vm_hugetlb_page(vma)) | |
274 | goto Einval; | |
275 | ||
276 | /* We can't remap across vm area boundaries */ | |
277 | if (old_len > vma->vm_end - addr) | |
278 | goto Efault; | |
279 | ||
982134ba LT |
280 | /* Need to be careful about a growing mapping */ |
281 | if (new_len > old_len) { | |
282 | unsigned long pgoff; | |
283 | ||
284 | if (vma->vm_flags & (VM_DONTEXPAND | VM_PFNMAP)) | |
54f5de70 | 285 | goto Efault; |
982134ba LT |
286 | pgoff = (addr - vma->vm_start) >> PAGE_SHIFT; |
287 | pgoff += vma->vm_pgoff; | |
288 | if (pgoff + (new_len >> PAGE_SHIFT) < pgoff) | |
289 | goto Einval; | |
54f5de70 AV |
290 | } |
291 | ||
292 | if (vma->vm_flags & VM_LOCKED) { | |
293 | unsigned long locked, lock_limit; | |
294 | locked = mm->locked_vm << PAGE_SHIFT; | |
59e99e5b | 295 | lock_limit = rlimit(RLIMIT_MEMLOCK); |
54f5de70 AV |
296 | locked += new_len - old_len; |
297 | if (locked > lock_limit && !capable(CAP_IPC_LOCK)) | |
298 | goto Eagain; | |
299 | } | |
300 | ||
301 | if (!may_expand_vm(mm, (new_len - old_len) >> PAGE_SHIFT)) | |
302 | goto Enomem; | |
303 | ||
304 | if (vma->vm_flags & VM_ACCOUNT) { | |
305 | unsigned long charged = (new_len - old_len) >> PAGE_SHIFT; | |
306 | if (security_vm_enough_memory(charged)) | |
307 | goto Efault; | |
308 | *p = charged; | |
309 | } | |
310 | ||
311 | return vma; | |
312 | ||
313 | Efault: /* very odd choice for most of the cases, but... */ | |
314 | return ERR_PTR(-EFAULT); | |
315 | Einval: | |
316 | return ERR_PTR(-EINVAL); | |
317 | Enomem: | |
318 | return ERR_PTR(-ENOMEM); | |
319 | Eagain: | |
320 | return ERR_PTR(-EAGAIN); | |
321 | } | |
322 | ||
ecc1a899 AV |
323 | static unsigned long mremap_to(unsigned long addr, |
324 | unsigned long old_len, unsigned long new_addr, | |
325 | unsigned long new_len) | |
326 | { | |
327 | struct mm_struct *mm = current->mm; | |
328 | struct vm_area_struct *vma; | |
329 | unsigned long ret = -EINVAL; | |
330 | unsigned long charged = 0; | |
097eed10 | 331 | unsigned long map_flags; |
ecc1a899 AV |
332 | |
333 | if (new_addr & ~PAGE_MASK) | |
334 | goto out; | |
335 | ||
336 | if (new_len > TASK_SIZE || new_addr > TASK_SIZE - new_len) | |
337 | goto out; | |
338 | ||
339 | /* Check if the location we're moving into overlaps the | |
340 | * old location at all, and fail if it does. | |
341 | */ | |
342 | if ((new_addr <= addr) && (new_addr+new_len) > addr) | |
343 | goto out; | |
344 | ||
345 | if ((addr <= new_addr) && (addr+old_len) > new_addr) | |
346 | goto out; | |
347 | ||
348 | ret = security_file_mmap(NULL, 0, 0, 0, new_addr, 1); | |
349 | if (ret) | |
350 | goto out; | |
351 | ||
352 | ret = do_munmap(mm, new_addr, new_len); | |
353 | if (ret) | |
354 | goto out; | |
355 | ||
356 | if (old_len >= new_len) { | |
357 | ret = do_munmap(mm, addr+new_len, old_len - new_len); | |
358 | if (ret && old_len != new_len) | |
359 | goto out; | |
360 | old_len = new_len; | |
361 | } | |
362 | ||
363 | vma = vma_to_resize(addr, old_len, new_len, &charged); | |
364 | if (IS_ERR(vma)) { | |
365 | ret = PTR_ERR(vma); | |
366 | goto out; | |
367 | } | |
368 | ||
097eed10 AV |
369 | map_flags = MAP_FIXED; |
370 | if (vma->vm_flags & VM_MAYSHARE) | |
371 | map_flags |= MAP_SHARED; | |
9206de95 | 372 | |
097eed10 AV |
373 | ret = get_unmapped_area(vma->vm_file, new_addr, new_len, vma->vm_pgoff + |
374 | ((addr - vma->vm_start) >> PAGE_SHIFT), | |
375 | map_flags); | |
ecc1a899 | 376 | if (ret & ~PAGE_MASK) |
097eed10 AV |
377 | goto out1; |
378 | ||
379 | ret = move_vma(vma, addr, old_len, new_len, new_addr); | |
380 | if (!(ret & ~PAGE_MASK)) | |
381 | goto out; | |
382 | out1: | |
383 | vm_unacct_memory(charged); | |
ecc1a899 AV |
384 | |
385 | out: | |
386 | return ret; | |
387 | } | |
388 | ||
1a0ef85f AV |
389 | static int vma_expandable(struct vm_area_struct *vma, unsigned long delta) |
390 | { | |
f106af4e | 391 | unsigned long end = vma->vm_end + delta; |
9206de95 | 392 | if (end < vma->vm_end) /* overflow */ |
f106af4e | 393 | return 0; |
9206de95 | 394 | if (vma->vm_next && vma->vm_next->vm_start < end) /* intersection */ |
f106af4e AV |
395 | return 0; |
396 | if (get_unmapped_area(NULL, vma->vm_start, end - vma->vm_start, | |
397 | 0, MAP_FIXED) & ~PAGE_MASK) | |
1a0ef85f | 398 | return 0; |
1a0ef85f AV |
399 | return 1; |
400 | } | |
401 | ||
1da177e4 LT |
402 | /* |
403 | * Expand (or shrink) an existing mapping, potentially moving it at the | |
404 | * same time (controlled by the MREMAP_MAYMOVE flag and available VM space) | |
405 | * | |
406 | * MREMAP_FIXED option added 5-Dec-1999 by Benjamin LaHaise | |
407 | * This option implies MREMAP_MAYMOVE. | |
408 | */ | |
409 | unsigned long do_mremap(unsigned long addr, | |
410 | unsigned long old_len, unsigned long new_len, | |
411 | unsigned long flags, unsigned long new_addr) | |
412 | { | |
d0de32d9 | 413 | struct mm_struct *mm = current->mm; |
1da177e4 LT |
414 | struct vm_area_struct *vma; |
415 | unsigned long ret = -EINVAL; | |
416 | unsigned long charged = 0; | |
417 | ||
418 | if (flags & ~(MREMAP_FIXED | MREMAP_MAYMOVE)) | |
419 | goto out; | |
420 | ||
421 | if (addr & ~PAGE_MASK) | |
422 | goto out; | |
423 | ||
424 | old_len = PAGE_ALIGN(old_len); | |
425 | new_len = PAGE_ALIGN(new_len); | |
426 | ||
427 | /* | |
428 | * We allow a zero old-len as a special case | |
429 | * for DOS-emu "duplicate shm area" thing. But | |
430 | * a zero new-len is nonsensical. | |
431 | */ | |
432 | if (!new_len) | |
433 | goto out; | |
434 | ||
1da177e4 | 435 | if (flags & MREMAP_FIXED) { |
ecc1a899 AV |
436 | if (flags & MREMAP_MAYMOVE) |
437 | ret = mremap_to(addr, old_len, new_addr, new_len); | |
438 | goto out; | |
1da177e4 LT |
439 | } |
440 | ||
441 | /* | |
442 | * Always allow a shrinking remap: that just unmaps | |
443 | * the unnecessary pages.. | |
444 | * do_munmap does all the needed commit accounting | |
445 | */ | |
446 | if (old_len >= new_len) { | |
d0de32d9 | 447 | ret = do_munmap(mm, addr+new_len, old_len - new_len); |
1da177e4 LT |
448 | if (ret && old_len != new_len) |
449 | goto out; | |
450 | ret = addr; | |
ecc1a899 | 451 | goto out; |
1da177e4 LT |
452 | } |
453 | ||
454 | /* | |
ecc1a899 | 455 | * Ok, we need to grow.. |
1da177e4 | 456 | */ |
54f5de70 AV |
457 | vma = vma_to_resize(addr, old_len, new_len, &charged); |
458 | if (IS_ERR(vma)) { | |
459 | ret = PTR_ERR(vma); | |
1da177e4 | 460 | goto out; |
119f657c | 461 | } |
1da177e4 | 462 | |
1da177e4 | 463 | /* old_len exactly to the end of the area.. |
1da177e4 | 464 | */ |
ecc1a899 | 465 | if (old_len == vma->vm_end - addr) { |
1da177e4 | 466 | /* can we just expand the current mapping? */ |
1a0ef85f | 467 | if (vma_expandable(vma, new_len - old_len)) { |
1da177e4 LT |
468 | int pages = (new_len - old_len) >> PAGE_SHIFT; |
469 | ||
5beb4930 RR |
470 | if (vma_adjust(vma, vma->vm_start, addr + new_len, |
471 | vma->vm_pgoff, NULL)) { | |
472 | ret = -ENOMEM; | |
473 | goto out; | |
474 | } | |
1da177e4 | 475 | |
d0de32d9 HD |
476 | mm->total_vm += pages; |
477 | vm_stat_account(mm, vma->vm_flags, vma->vm_file, pages); | |
1da177e4 | 478 | if (vma->vm_flags & VM_LOCKED) { |
d0de32d9 | 479 | mm->locked_vm += pages; |
ba470de4 | 480 | mlock_vma_pages_range(vma, addr + old_len, |
1da177e4 LT |
481 | addr + new_len); |
482 | } | |
483 | ret = addr; | |
484 | goto out; | |
485 | } | |
486 | } | |
487 | ||
488 | /* | |
489 | * We weren't able to just expand or shrink the area, | |
490 | * we need to create a new one and move it.. | |
491 | */ | |
492 | ret = -ENOMEM; | |
493 | if (flags & MREMAP_MAYMOVE) { | |
ecc1a899 AV |
494 | unsigned long map_flags = 0; |
495 | if (vma->vm_flags & VM_MAYSHARE) | |
496 | map_flags |= MAP_SHARED; | |
497 | ||
498 | new_addr = get_unmapped_area(vma->vm_file, 0, new_len, | |
93587414 AV |
499 | vma->vm_pgoff + |
500 | ((addr - vma->vm_start) >> PAGE_SHIFT), | |
501 | map_flags); | |
ecc1a899 AV |
502 | if (new_addr & ~PAGE_MASK) { |
503 | ret = new_addr; | |
504 | goto out; | |
1da177e4 | 505 | } |
ecc1a899 AV |
506 | |
507 | ret = security_file_mmap(NULL, 0, 0, 0, new_addr, 1); | |
508 | if (ret) | |
509 | goto out; | |
1da177e4 LT |
510 | ret = move_vma(vma, addr, old_len, new_len, new_addr); |
511 | } | |
512 | out: | |
513 | if (ret & ~PAGE_MASK) | |
514 | vm_unacct_memory(charged); | |
1da177e4 LT |
515 | return ret; |
516 | } | |
517 | ||
6a6160a7 HC |
518 | SYSCALL_DEFINE5(mremap, unsigned long, addr, unsigned long, old_len, |
519 | unsigned long, new_len, unsigned long, flags, | |
520 | unsigned long, new_addr) | |
1da177e4 LT |
521 | { |
522 | unsigned long ret; | |
523 | ||
524 | down_write(¤t->mm->mmap_sem); | |
525 | ret = do_mremap(addr, old_len, new_len, flags, new_addr); | |
526 | up_write(¤t->mm->mmap_sem); | |
527 | return ret; | |
528 | } |