Commit | Line | Data |
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b2441318 | 1 | // SPDX-License-Identifier: GPL-2.0 |
1da177e4 LT |
2 | /* |
3 | * linux/mm/madvise.c | |
4 | * | |
5 | * Copyright (C) 1999 Linus Torvalds | |
6 | * Copyright (C) 2002 Christoph Hellwig | |
7 | */ | |
8 | ||
9 | #include <linux/mman.h> | |
10 | #include <linux/pagemap.h> | |
11 | #include <linux/syscalls.h> | |
05b74384 | 12 | #include <linux/mempolicy.h> |
afcf938e | 13 | #include <linux/page-isolation.h> |
9c276cc6 | 14 | #include <linux/page_idle.h> |
05ce7724 | 15 | #include <linux/userfaultfd_k.h> |
1da177e4 | 16 | #include <linux/hugetlb.h> |
3f31d075 | 17 | #include <linux/falloc.h> |
692fe624 | 18 | #include <linux/fadvise.h> |
e8edc6e0 | 19 | #include <linux/sched.h> |
ecb8ac8b | 20 | #include <linux/sched/mm.h> |
17fca131 | 21 | #include <linux/mm_inline.h> |
9a10064f | 22 | #include <linux/string.h> |
ecb8ac8b | 23 | #include <linux/uio.h> |
f8af4da3 | 24 | #include <linux/ksm.h> |
3f31d075 | 25 | #include <linux/fs.h> |
9ab4233d | 26 | #include <linux/file.h> |
1998cc04 | 27 | #include <linux/blkdev.h> |
66114cad | 28 | #include <linux/backing-dev.h> |
a520110e | 29 | #include <linux/pagewalk.h> |
1998cc04 SL |
30 | #include <linux/swap.h> |
31 | #include <linux/swapops.h> | |
3a4f8a0b | 32 | #include <linux/shmem_fs.h> |
854e9ed0 MK |
33 | #include <linux/mmu_notifier.h> |
34 | ||
35 | #include <asm/tlb.h> | |
1da177e4 | 36 | |
23519073 | 37 | #include "internal.h" |
014bb1de | 38 | #include "swap.h" |
23519073 | 39 | |
d616d512 MK |
40 | struct madvise_walk_private { |
41 | struct mmu_gather *tlb; | |
42 | bool pageout; | |
43 | }; | |
44 | ||
0a27a14a NP |
45 | /* |
46 | * Any behaviour which results in changes to the vma->vm_flags needs to | |
c1e8d7c6 | 47 | * take mmap_lock for writing. Others, which simply traverse vmas, need |
0a27a14a NP |
48 | * to only take it for reading. |
49 | */ | |
50 | static int madvise_need_mmap_write(int behavior) | |
51 | { | |
52 | switch (behavior) { | |
53 | case MADV_REMOVE: | |
54 | case MADV_WILLNEED: | |
55 | case MADV_DONTNEED: | |
9457056a | 56 | case MADV_DONTNEED_LOCKED: |
9c276cc6 | 57 | case MADV_COLD: |
1a4e58cc | 58 | case MADV_PAGEOUT: |
854e9ed0 | 59 | case MADV_FREE: |
4ca9b385 DH |
60 | case MADV_POPULATE_READ: |
61 | case MADV_POPULATE_WRITE: | |
7d8faaf1 | 62 | case MADV_COLLAPSE: |
0a27a14a NP |
63 | return 0; |
64 | default: | |
65 | /* be safe, default to 1. list exceptions explicitly */ | |
66 | return 1; | |
67 | } | |
68 | } | |
69 | ||
9a10064f | 70 | #ifdef CONFIG_ANON_VMA_NAME |
5c26f6ac | 71 | struct anon_vma_name *anon_vma_name_alloc(const char *name) |
78db3412 SB |
72 | { |
73 | struct anon_vma_name *anon_name; | |
74 | size_t count; | |
75 | ||
76 | /* Add 1 for NUL terminator at the end of the anon_name->name */ | |
77 | count = strlen(name) + 1; | |
78 | anon_name = kmalloc(struct_size(anon_name, name, count), GFP_KERNEL); | |
79 | if (anon_name) { | |
80 | kref_init(&anon_name->kref); | |
81 | memcpy(anon_name->name, name, count); | |
82 | } | |
83 | ||
84 | return anon_name; | |
85 | } | |
86 | ||
5c26f6ac | 87 | void anon_vma_name_free(struct kref *kref) |
78db3412 SB |
88 | { |
89 | struct anon_vma_name *anon_name = | |
90 | container_of(kref, struct anon_vma_name, kref); | |
91 | kfree(anon_name); | |
92 | } | |
93 | ||
5c26f6ac | 94 | struct anon_vma_name *anon_vma_name(struct vm_area_struct *vma) |
9a10064f | 95 | { |
9a10064f CC |
96 | mmap_assert_locked(vma->vm_mm); |
97 | ||
5c26f6ac | 98 | return vma->anon_name; |
9a10064f CC |
99 | } |
100 | ||
101 | /* mmap_lock should be write-locked */ | |
5c26f6ac SB |
102 | static int replace_anon_vma_name(struct vm_area_struct *vma, |
103 | struct anon_vma_name *anon_name) | |
9a10064f | 104 | { |
5c26f6ac | 105 | struct anon_vma_name *orig_name = anon_vma_name(vma); |
78db3412 | 106 | |
5c26f6ac SB |
107 | if (!anon_name) { |
108 | vma->anon_name = NULL; | |
109 | anon_vma_name_put(orig_name); | |
9a10064f CC |
110 | return 0; |
111 | } | |
112 | ||
5c26f6ac SB |
113 | if (anon_vma_name_eq(orig_name, anon_name)) |
114 | return 0; | |
9a10064f | 115 | |
96403e11 | 116 | vma->anon_name = anon_vma_name_reuse(anon_name); |
5c26f6ac | 117 | anon_vma_name_put(orig_name); |
9a10064f CC |
118 | |
119 | return 0; | |
120 | } | |
121 | #else /* CONFIG_ANON_VMA_NAME */ | |
5c26f6ac SB |
122 | static int replace_anon_vma_name(struct vm_area_struct *vma, |
123 | struct anon_vma_name *anon_name) | |
9a10064f | 124 | { |
5c26f6ac | 125 | if (anon_name) |
9a10064f CC |
126 | return -EINVAL; |
127 | ||
128 | return 0; | |
129 | } | |
130 | #endif /* CONFIG_ANON_VMA_NAME */ | |
1da177e4 | 131 | /* |
ac1e9acc | 132 | * Update the vm_flags on region of a vma, splitting it or merging it as |
8651a137 | 133 | * necessary. Must be called with mmap_lock held for writing; |
942341dc SB |
134 | * Caller should ensure anon_name stability by raising its refcount even when |
135 | * anon_name belongs to a valid vma because this function might free that vma. | |
1da177e4 | 136 | */ |
ac1e9acc CC |
137 | static int madvise_update_vma(struct vm_area_struct *vma, |
138 | struct vm_area_struct **prev, unsigned long start, | |
9a10064f | 139 | unsigned long end, unsigned long new_flags, |
5c26f6ac | 140 | struct anon_vma_name *anon_name) |
1da177e4 | 141 | { |
ec9bed9d | 142 | struct mm_struct *mm = vma->vm_mm; |
ac1e9acc | 143 | int error; |
05b74384 | 144 | pgoff_t pgoff; |
85ab779e | 145 | VMA_ITERATOR(vmi, mm, start); |
e798c6e8 | 146 | |
5c26f6ac | 147 | if (new_flags == vma->vm_flags && anon_vma_name_eq(anon_vma_name(vma), anon_name)) { |
05b74384 | 148 | *prev = vma; |
ac1e9acc | 149 | return 0; |
05b74384 PM |
150 | } |
151 | ||
152 | pgoff = vma->vm_pgoff + ((start - vma->vm_start) >> PAGE_SHIFT); | |
9760ebff | 153 | *prev = vma_merge(&vmi, mm, *prev, start, end, new_flags, |
178e22ac | 154 | vma->anon_vma, vma->vm_file, pgoff, vma_policy(vma), |
5c26f6ac | 155 | vma->vm_userfaultfd_ctx, anon_name); |
05b74384 PM |
156 | if (*prev) { |
157 | vma = *prev; | |
158 | goto success; | |
159 | } | |
160 | ||
161 | *prev = vma; | |
1da177e4 LT |
162 | |
163 | if (start != vma->vm_start) { | |
85ab779e | 164 | error = split_vma(&vmi, vma, start, 1); |
f3bc0dba | 165 | if (error) |
ac1e9acc | 166 | return error; |
1da177e4 LT |
167 | } |
168 | ||
169 | if (end != vma->vm_end) { | |
85ab779e | 170 | error = split_vma(&vmi, vma, end, 0); |
f3bc0dba | 171 | if (error) |
ac1e9acc | 172 | return error; |
1da177e4 LT |
173 | } |
174 | ||
836d5ffd | 175 | success: |
1da177e4 | 176 | /* |
c1e8d7c6 | 177 | * vm_flags is protected by the mmap_lock held in write mode. |
1da177e4 | 178 | */ |
1c71222e | 179 | vm_flags_reset(vma, new_flags); |
d09e8ca6 | 180 | if (!vma->vm_file || vma_is_anon_shmem(vma)) { |
5c26f6ac | 181 | error = replace_anon_vma_name(vma, anon_name); |
9a10064f CC |
182 | if (error) |
183 | return error; | |
184 | } | |
f3bc0dba | 185 | |
ac1e9acc | 186 | return 0; |
1da177e4 LT |
187 | } |
188 | ||
1998cc04 SL |
189 | #ifdef CONFIG_SWAP |
190 | static int swapin_walk_pmd_entry(pmd_t *pmd, unsigned long start, | |
f3cd4ab0 | 191 | unsigned long end, struct mm_walk *walk) |
1998cc04 | 192 | { |
1998cc04 | 193 | struct vm_area_struct *vma = walk->private; |
5169b844 | 194 | struct swap_iocb *splug = NULL; |
f3cd4ab0 HD |
195 | pte_t *ptep = NULL; |
196 | spinlock_t *ptl; | |
197 | unsigned long addr; | |
1998cc04 | 198 | |
f3cd4ab0 | 199 | for (addr = start; addr < end; addr += PAGE_SIZE) { |
1998cc04 SL |
200 | pte_t pte; |
201 | swp_entry_t entry; | |
202 | struct page *page; | |
1998cc04 | 203 | |
f3cd4ab0 HD |
204 | if (!ptep++) { |
205 | ptep = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); | |
206 | if (!ptep) | |
207 | break; | |
208 | } | |
1998cc04 | 209 | |
c33c7948 | 210 | pte = ptep_get(ptep); |
f7cc67ae | 211 | if (!is_swap_pte(pte)) |
1998cc04 SL |
212 | continue; |
213 | entry = pte_to_swp_entry(pte); | |
214 | if (unlikely(non_swap_entry(entry))) | |
215 | continue; | |
216 | ||
f3cd4ab0 HD |
217 | pte_unmap_unlock(ptep, ptl); |
218 | ptep = NULL; | |
219 | ||
1998cc04 | 220 | page = read_swap_cache_async(entry, GFP_HIGHUSER_MOVABLE, |
f3cd4ab0 | 221 | vma, addr, false, &splug); |
1998cc04 | 222 | if (page) |
09cbfeaf | 223 | put_page(page); |
1998cc04 | 224 | } |
f3cd4ab0 HD |
225 | |
226 | if (ptep) | |
227 | pte_unmap_unlock(ptep, ptl); | |
5169b844 | 228 | swap_read_unplug(splug); |
de2e5171 | 229 | cond_resched(); |
1998cc04 SL |
230 | |
231 | return 0; | |
232 | } | |
233 | ||
7b86ac33 CH |
234 | static const struct mm_walk_ops swapin_walk_ops = { |
235 | .pmd_entry = swapin_walk_pmd_entry, | |
236 | }; | |
1998cc04 | 237 | |
179d3e4f | 238 | static void shmem_swapin_range(struct vm_area_struct *vma, |
1998cc04 SL |
239 | unsigned long start, unsigned long end, |
240 | struct address_space *mapping) | |
241 | { | |
e6e88712 | 242 | XA_STATE(xas, &mapping->i_pages, linear_page_index(vma, start)); |
179d3e4f | 243 | pgoff_t end_index = linear_page_index(vma, end) - 1; |
1998cc04 | 244 | struct page *page; |
5169b844 | 245 | struct swap_iocb *splug = NULL; |
1998cc04 | 246 | |
e6e88712 MWO |
247 | rcu_read_lock(); |
248 | xas_for_each(&xas, page, end_index) { | |
179d3e4f HD |
249 | unsigned long addr; |
250 | swp_entry_t entry; | |
1998cc04 | 251 | |
e6e88712 | 252 | if (!xa_is_value(page)) |
1998cc04 | 253 | continue; |
179d3e4f | 254 | entry = radix_to_swp_entry(page); |
ba6851b4 | 255 | /* There might be swapin error entries in shmem mapping. */ |
179d3e4f | 256 | if (non_swap_entry(entry)) |
ba6851b4 | 257 | continue; |
179d3e4f HD |
258 | |
259 | addr = vma->vm_start + | |
260 | ((xas.xa_index - vma->vm_pgoff) << PAGE_SHIFT); | |
e6e88712 MWO |
261 | xas_pause(&xas); |
262 | rcu_read_unlock(); | |
263 | ||
179d3e4f HD |
264 | page = read_swap_cache_async(entry, mapping_gfp_mask(mapping), |
265 | vma, addr, false, &splug); | |
1998cc04 | 266 | if (page) |
09cbfeaf | 267 | put_page(page); |
e6e88712 MWO |
268 | |
269 | rcu_read_lock(); | |
1998cc04 | 270 | } |
e6e88712 | 271 | rcu_read_unlock(); |
5169b844 | 272 | swap_read_unplug(splug); |
1998cc04 SL |
273 | } |
274 | #endif /* CONFIG_SWAP */ | |
275 | ||
1da177e4 LT |
276 | /* |
277 | * Schedule all required I/O operations. Do not wait for completion. | |
278 | */ | |
ec9bed9d VC |
279 | static long madvise_willneed(struct vm_area_struct *vma, |
280 | struct vm_area_struct **prev, | |
1da177e4 LT |
281 | unsigned long start, unsigned long end) |
282 | { | |
0726b01e | 283 | struct mm_struct *mm = vma->vm_mm; |
1da177e4 | 284 | struct file *file = vma->vm_file; |
692fe624 | 285 | loff_t offset; |
1da177e4 | 286 | |
6ea8d958 | 287 | *prev = vma; |
1998cc04 | 288 | #ifdef CONFIG_SWAP |
97b713ba | 289 | if (!file) { |
7b86ac33 CH |
290 | walk_page_range(vma->vm_mm, start, end, &swapin_walk_ops, vma); |
291 | lru_add_drain(); /* Push any new pages onto the LRU now */ | |
1998cc04 SL |
292 | return 0; |
293 | } | |
1998cc04 | 294 | |
97b713ba | 295 | if (shmem_mapping(file->f_mapping)) { |
179d3e4f HD |
296 | shmem_swapin_range(vma, start, end, file->f_mapping); |
297 | lru_add_drain(); /* Push any new pages onto the LRU now */ | |
97b713ba CH |
298 | return 0; |
299 | } | |
300 | #else | |
1bef4003 S |
301 | if (!file) |
302 | return -EBADF; | |
97b713ba | 303 | #endif |
1bef4003 | 304 | |
e748dcd0 | 305 | if (IS_DAX(file_inode(file))) { |
fe77ba6f CO |
306 | /* no bad return value, but ignore advice */ |
307 | return 0; | |
308 | } | |
309 | ||
692fe624 JK |
310 | /* |
311 | * Filesystem's fadvise may need to take various locks. We need to | |
312 | * explicitly grab a reference because the vma (and hence the | |
313 | * vma's reference to the file) can go away as soon as we drop | |
c1e8d7c6 | 314 | * mmap_lock. |
692fe624 | 315 | */ |
c1e8d7c6 | 316 | *prev = NULL; /* tell sys_madvise we drop mmap_lock */ |
692fe624 | 317 | get_file(file); |
692fe624 JK |
318 | offset = (loff_t)(start - vma->vm_start) |
319 | + ((loff_t)vma->vm_pgoff << PAGE_SHIFT); | |
0726b01e | 320 | mmap_read_unlock(mm); |
692fe624 JK |
321 | vfs_fadvise(file, offset, end - start, POSIX_FADV_WILLNEED); |
322 | fput(file); | |
0726b01e | 323 | mmap_read_lock(mm); |
1da177e4 LT |
324 | return 0; |
325 | } | |
326 | ||
fd3b1bc3 PK |
327 | static inline bool can_do_file_pageout(struct vm_area_struct *vma) |
328 | { | |
329 | if (!vma->vm_file) | |
330 | return false; | |
331 | /* | |
332 | * paging out pagecache only for non-anonymous mappings that correspond | |
333 | * to the files the calling process could (if tried) open for writing; | |
334 | * otherwise we'd be including shared non-exclusive mappings, which | |
335 | * opens a side channel. | |
336 | */ | |
01beba79 | 337 | return inode_owner_or_capable(&nop_mnt_idmap, |
fd3b1bc3 PK |
338 | file_inode(vma->vm_file)) || |
339 | file_permission(vma->vm_file, MAY_WRITE) == 0; | |
340 | } | |
341 | ||
d616d512 MK |
342 | static int madvise_cold_or_pageout_pte_range(pmd_t *pmd, |
343 | unsigned long addr, unsigned long end, | |
344 | struct mm_walk *walk) | |
9c276cc6 | 345 | { |
d616d512 MK |
346 | struct madvise_walk_private *private = walk->private; |
347 | struct mmu_gather *tlb = private->tlb; | |
348 | bool pageout = private->pageout; | |
9c276cc6 MK |
349 | struct mm_struct *mm = tlb->mm; |
350 | struct vm_area_struct *vma = walk->vma; | |
f3cd4ab0 | 351 | pte_t *start_pte, *pte, ptent; |
9c276cc6 | 352 | spinlock_t *ptl; |
07e8c82b VMO |
353 | struct folio *folio = NULL; |
354 | LIST_HEAD(folio_list); | |
fd3b1bc3 | 355 | bool pageout_anon_only_filter; |
d616d512 MK |
356 | |
357 | if (fatal_signal_pending(current)) | |
358 | return -EINTR; | |
9c276cc6 | 359 | |
fd3b1bc3 PK |
360 | pageout_anon_only_filter = pageout && !vma_is_anonymous(vma) && |
361 | !can_do_file_pageout(vma); | |
362 | ||
9c276cc6 MK |
363 | #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
364 | if (pmd_trans_huge(*pmd)) { | |
365 | pmd_t orig_pmd; | |
366 | unsigned long next = pmd_addr_end(addr, end); | |
367 | ||
368 | tlb_change_page_size(tlb, HPAGE_PMD_SIZE); | |
369 | ptl = pmd_trans_huge_lock(pmd, vma); | |
370 | if (!ptl) | |
371 | return 0; | |
372 | ||
373 | orig_pmd = *pmd; | |
374 | if (is_huge_zero_pmd(orig_pmd)) | |
375 | goto huge_unlock; | |
376 | ||
377 | if (unlikely(!pmd_present(orig_pmd))) { | |
378 | VM_BUG_ON(thp_migration_supported() && | |
379 | !is_pmd_migration_entry(orig_pmd)); | |
380 | goto huge_unlock; | |
381 | } | |
382 | ||
07e8c82b | 383 | folio = pfn_folio(pmd_pfn(orig_pmd)); |
12e967fd | 384 | |
07e8c82b VMO |
385 | /* Do not interfere with other mappings of this folio */ |
386 | if (folio_mapcount(folio) != 1) | |
12e967fd MH |
387 | goto huge_unlock; |
388 | ||
07e8c82b | 389 | if (pageout_anon_only_filter && !folio_test_anon(folio)) |
fd3b1bc3 PK |
390 | goto huge_unlock; |
391 | ||
9c276cc6 MK |
392 | if (next - addr != HPAGE_PMD_SIZE) { |
393 | int err; | |
394 | ||
07e8c82b | 395 | folio_get(folio); |
9c276cc6 | 396 | spin_unlock(ptl); |
07e8c82b VMO |
397 | folio_lock(folio); |
398 | err = split_folio(folio); | |
399 | folio_unlock(folio); | |
400 | folio_put(folio); | |
9c276cc6 | 401 | if (!err) |
07e8c82b | 402 | goto regular_folio; |
9c276cc6 MK |
403 | return 0; |
404 | } | |
405 | ||
406 | if (pmd_young(orig_pmd)) { | |
407 | pmdp_invalidate(vma, addr, pmd); | |
408 | orig_pmd = pmd_mkold(orig_pmd); | |
409 | ||
410 | set_pmd_at(mm, addr, pmd, orig_pmd); | |
411 | tlb_remove_pmd_tlb_entry(tlb, pmd, addr); | |
412 | } | |
413 | ||
07e8c82b VMO |
414 | folio_clear_referenced(folio); |
415 | folio_test_clear_young(folio); | |
d616d512 | 416 | if (pageout) { |
be2d5756 | 417 | if (folio_isolate_lru(folio)) { |
07e8c82b VMO |
418 | if (folio_test_unevictable(folio)) |
419 | folio_putback_lru(folio); | |
82072962 | 420 | else |
07e8c82b | 421 | list_add(&folio->lru, &folio_list); |
82072962 | 422 | } |
d616d512 | 423 | } else |
5a9e3474 | 424 | folio_deactivate(folio); |
9c276cc6 MK |
425 | huge_unlock: |
426 | spin_unlock(ptl); | |
d616d512 | 427 | if (pageout) |
07e8c82b | 428 | reclaim_pages(&folio_list); |
9c276cc6 MK |
429 | return 0; |
430 | } | |
431 | ||
07e8c82b | 432 | regular_folio: |
9c276cc6 MK |
433 | #endif |
434 | tlb_change_page_size(tlb, PAGE_SIZE); | |
f3cd4ab0 HD |
435 | start_pte = pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); |
436 | if (!start_pte) | |
437 | return 0; | |
9c276cc6 MK |
438 | flush_tlb_batched_pending(mm); |
439 | arch_enter_lazy_mmu_mode(); | |
440 | for (; addr < end; pte++, addr += PAGE_SIZE) { | |
c33c7948 | 441 | ptent = ptep_get(pte); |
9c276cc6 MK |
442 | |
443 | if (pte_none(ptent)) | |
444 | continue; | |
445 | ||
446 | if (!pte_present(ptent)) | |
447 | continue; | |
448 | ||
07e8c82b VMO |
449 | folio = vm_normal_folio(vma, addr, ptent); |
450 | if (!folio || folio_is_zone_device(folio)) | |
9c276cc6 MK |
451 | continue; |
452 | ||
453 | /* | |
454 | * Creating a THP page is expensive so split it only if we | |
455 | * are sure it's worth. Split it if we are only owner. | |
456 | */ | |
07e8c82b | 457 | if (folio_test_large(folio)) { |
f3cd4ab0 HD |
458 | int err; |
459 | ||
07e8c82b | 460 | if (folio_mapcount(folio) != 1) |
9c276cc6 | 461 | break; |
07e8c82b | 462 | if (pageout_anon_only_filter && !folio_test_anon(folio)) |
fd3b1bc3 | 463 | break; |
f3cd4ab0 | 464 | if (!folio_trylock(folio)) |
9c276cc6 | 465 | break; |
f3cd4ab0 HD |
466 | folio_get(folio); |
467 | arch_leave_lazy_mmu_mode(); | |
468 | pte_unmap_unlock(start_pte, ptl); | |
469 | start_pte = NULL; | |
470 | err = split_folio(folio); | |
07e8c82b VMO |
471 | folio_unlock(folio); |
472 | folio_put(folio); | |
f3cd4ab0 HD |
473 | if (err) |
474 | break; | |
475 | start_pte = pte = | |
476 | pte_offset_map_lock(mm, pmd, addr, &ptl); | |
477 | if (!start_pte) | |
478 | break; | |
479 | arch_enter_lazy_mmu_mode(); | |
9c276cc6 MK |
480 | pte--; |
481 | addr -= PAGE_SIZE; | |
482 | continue; | |
483 | } | |
484 | ||
58d426a7 | 485 | /* |
07e8c82b VMO |
486 | * Do not interfere with other mappings of this folio and |
487 | * non-LRU folio. | |
58d426a7 | 488 | */ |
07e8c82b | 489 | if (!folio_test_lru(folio) || folio_mapcount(folio) != 1) |
12e967fd MH |
490 | continue; |
491 | ||
07e8c82b | 492 | if (pageout_anon_only_filter && !folio_test_anon(folio)) |
fd3b1bc3 PK |
493 | continue; |
494 | ||
07e8c82b | 495 | VM_BUG_ON_FOLIO(folio_test_large(folio), folio); |
9c276cc6 MK |
496 | |
497 | if (pte_young(ptent)) { | |
498 | ptent = ptep_get_and_clear_full(mm, addr, pte, | |
499 | tlb->fullmm); | |
500 | ptent = pte_mkold(ptent); | |
501 | set_pte_at(mm, addr, pte, ptent); | |
502 | tlb_remove_tlb_entry(tlb, pte, addr); | |
503 | } | |
504 | ||
505 | /* | |
07e8c82b VMO |
506 | * We are deactivating a folio for accelerating reclaiming. |
507 | * VM couldn't reclaim the folio unless we clear PG_young. | |
9c276cc6 MK |
508 | * As a side effect, it makes confuse idle-page tracking |
509 | * because they will miss recent referenced history. | |
510 | */ | |
07e8c82b VMO |
511 | folio_clear_referenced(folio); |
512 | folio_test_clear_young(folio); | |
d616d512 | 513 | if (pageout) { |
be2d5756 | 514 | if (folio_isolate_lru(folio)) { |
07e8c82b VMO |
515 | if (folio_test_unevictable(folio)) |
516 | folio_putback_lru(folio); | |
82072962 | 517 | else |
07e8c82b | 518 | list_add(&folio->lru, &folio_list); |
82072962 | 519 | } |
d616d512 | 520 | } else |
5a9e3474 | 521 | folio_deactivate(folio); |
9c276cc6 MK |
522 | } |
523 | ||
f3cd4ab0 HD |
524 | if (start_pte) { |
525 | arch_leave_lazy_mmu_mode(); | |
526 | pte_unmap_unlock(start_pte, ptl); | |
527 | } | |
d616d512 | 528 | if (pageout) |
07e8c82b | 529 | reclaim_pages(&folio_list); |
9c276cc6 MK |
530 | cond_resched(); |
531 | ||
532 | return 0; | |
533 | } | |
534 | ||
535 | static const struct mm_walk_ops cold_walk_ops = { | |
d616d512 | 536 | .pmd_entry = madvise_cold_or_pageout_pte_range, |
9c276cc6 MK |
537 | }; |
538 | ||
539 | static void madvise_cold_page_range(struct mmu_gather *tlb, | |
540 | struct vm_area_struct *vma, | |
541 | unsigned long addr, unsigned long end) | |
542 | { | |
d616d512 MK |
543 | struct madvise_walk_private walk_private = { |
544 | .pageout = false, | |
545 | .tlb = tlb, | |
546 | }; | |
547 | ||
9c276cc6 | 548 | tlb_start_vma(tlb, vma); |
d616d512 | 549 | walk_page_range(vma->vm_mm, addr, end, &cold_walk_ops, &walk_private); |
9c276cc6 MK |
550 | tlb_end_vma(tlb, vma); |
551 | } | |
552 | ||
a213e5cf HD |
553 | static inline bool can_madv_lru_vma(struct vm_area_struct *vma) |
554 | { | |
9457056a | 555 | return !(vma->vm_flags & (VM_LOCKED|VM_PFNMAP|VM_HUGETLB)); |
a213e5cf HD |
556 | } |
557 | ||
9c276cc6 MK |
558 | static long madvise_cold(struct vm_area_struct *vma, |
559 | struct vm_area_struct **prev, | |
560 | unsigned long start_addr, unsigned long end_addr) | |
561 | { | |
562 | struct mm_struct *mm = vma->vm_mm; | |
563 | struct mmu_gather tlb; | |
564 | ||
565 | *prev = vma; | |
566 | if (!can_madv_lru_vma(vma)) | |
567 | return -EINVAL; | |
568 | ||
569 | lru_add_drain(); | |
a72afd87 | 570 | tlb_gather_mmu(&tlb, mm); |
9c276cc6 | 571 | madvise_cold_page_range(&tlb, vma, start_addr, end_addr); |
ae8eba8b | 572 | tlb_finish_mmu(&tlb); |
9c276cc6 MK |
573 | |
574 | return 0; | |
575 | } | |
576 | ||
1a4e58cc MK |
577 | static void madvise_pageout_page_range(struct mmu_gather *tlb, |
578 | struct vm_area_struct *vma, | |
579 | unsigned long addr, unsigned long end) | |
580 | { | |
d616d512 MK |
581 | struct madvise_walk_private walk_private = { |
582 | .pageout = true, | |
583 | .tlb = tlb, | |
584 | }; | |
585 | ||
1a4e58cc | 586 | tlb_start_vma(tlb, vma); |
d616d512 | 587 | walk_page_range(vma->vm_mm, addr, end, &cold_walk_ops, &walk_private); |
1a4e58cc MK |
588 | tlb_end_vma(tlb, vma); |
589 | } | |
590 | ||
1a4e58cc MK |
591 | static long madvise_pageout(struct vm_area_struct *vma, |
592 | struct vm_area_struct **prev, | |
593 | unsigned long start_addr, unsigned long end_addr) | |
594 | { | |
595 | struct mm_struct *mm = vma->vm_mm; | |
596 | struct mmu_gather tlb; | |
597 | ||
598 | *prev = vma; | |
599 | if (!can_madv_lru_vma(vma)) | |
600 | return -EINVAL; | |
601 | ||
fd3b1bc3 PK |
602 | /* |
603 | * If the VMA belongs to a private file mapping, there can be private | |
604 | * dirty pages which can be paged out if even this process is neither | |
605 | * owner nor write capable of the file. We allow private file mappings | |
606 | * further to pageout dirty anon pages. | |
607 | */ | |
608 | if (!vma_is_anonymous(vma) && (!can_do_file_pageout(vma) && | |
609 | (vma->vm_flags & VM_MAYSHARE))) | |
1a4e58cc MK |
610 | return 0; |
611 | ||
612 | lru_add_drain(); | |
a72afd87 | 613 | tlb_gather_mmu(&tlb, mm); |
1a4e58cc | 614 | madvise_pageout_page_range(&tlb, vma, start_addr, end_addr); |
ae8eba8b | 615 | tlb_finish_mmu(&tlb); |
1a4e58cc MK |
616 | |
617 | return 0; | |
618 | } | |
619 | ||
854e9ed0 MK |
620 | static int madvise_free_pte_range(pmd_t *pmd, unsigned long addr, |
621 | unsigned long end, struct mm_walk *walk) | |
622 | ||
623 | { | |
624 | struct mmu_gather *tlb = walk->private; | |
625 | struct mm_struct *mm = tlb->mm; | |
626 | struct vm_area_struct *vma = walk->vma; | |
627 | spinlock_t *ptl; | |
f3cd4ab0 | 628 | pte_t *start_pte, *pte, ptent; |
98b211d6 | 629 | struct folio *folio; |
64b42bc1 | 630 | int nr_swap = 0; |
b8d3c4c3 MK |
631 | unsigned long next; |
632 | ||
633 | next = pmd_addr_end(addr, end); | |
634 | if (pmd_trans_huge(*pmd)) | |
635 | if (madvise_free_huge_pmd(tlb, vma, pmd, addr, next)) | |
f3cd4ab0 | 636 | return 0; |
854e9ed0 | 637 | |
ed6a7935 | 638 | tlb_change_page_size(tlb, PAGE_SIZE); |
f3cd4ab0 HD |
639 | start_pte = pte = pte_offset_map_lock(mm, pmd, addr, &ptl); |
640 | if (!start_pte) | |
641 | return 0; | |
3ea27719 | 642 | flush_tlb_batched_pending(mm); |
854e9ed0 MK |
643 | arch_enter_lazy_mmu_mode(); |
644 | for (; addr != end; pte++, addr += PAGE_SIZE) { | |
c33c7948 | 645 | ptent = ptep_get(pte); |
854e9ed0 | 646 | |
64b42bc1 | 647 | if (pte_none(ptent)) |
854e9ed0 | 648 | continue; |
64b42bc1 MK |
649 | /* |
650 | * If the pte has swp_entry, just clear page table to | |
651 | * prevent swap-in which is more expensive rather than | |
652 | * (page allocation + zeroing). | |
653 | */ | |
654 | if (!pte_present(ptent)) { | |
655 | swp_entry_t entry; | |
656 | ||
657 | entry = pte_to_swp_entry(ptent); | |
7b49514f ML |
658 | if (!non_swap_entry(entry)) { |
659 | nr_swap--; | |
660 | free_swap_and_cache(entry); | |
661 | pte_clear_not_present_full(mm, addr, pte, tlb->fullmm); | |
662 | } else if (is_hwpoison_entry(entry) || | |
663 | is_swapin_error_entry(entry)) { | |
664 | pte_clear_not_present_full(mm, addr, pte, tlb->fullmm); | |
665 | } | |
64b42bc1 MK |
666 | continue; |
667 | } | |
854e9ed0 | 668 | |
4947ed93 KW |
669 | folio = vm_normal_folio(vma, addr, ptent); |
670 | if (!folio || folio_is_zone_device(folio)) | |
854e9ed0 MK |
671 | continue; |
672 | ||
673 | /* | |
98b211d6 | 674 | * If pmd isn't transhuge but the folio is large and |
854e9ed0 MK |
675 | * is owned by only this process, split it and |
676 | * deactivate all pages. | |
677 | */ | |
98b211d6 | 678 | if (folio_test_large(folio)) { |
f3cd4ab0 HD |
679 | int err; |
680 | ||
98b211d6 | 681 | if (folio_mapcount(folio) != 1) |
f3cd4ab0 HD |
682 | break; |
683 | if (!folio_trylock(folio)) | |
684 | break; | |
98b211d6 | 685 | folio_get(folio); |
f3cd4ab0 HD |
686 | arch_leave_lazy_mmu_mode(); |
687 | pte_unmap_unlock(start_pte, ptl); | |
688 | start_pte = NULL; | |
689 | err = split_folio(folio); | |
98b211d6 MWO |
690 | folio_unlock(folio); |
691 | folio_put(folio); | |
f3cd4ab0 HD |
692 | if (err) |
693 | break; | |
694 | start_pte = pte = | |
695 | pte_offset_map_lock(mm, pmd, addr, &ptl); | |
696 | if (!start_pte) | |
697 | break; | |
698 | arch_enter_lazy_mmu_mode(); | |
854e9ed0 MK |
699 | pte--; |
700 | addr -= PAGE_SIZE; | |
701 | continue; | |
702 | } | |
703 | ||
98b211d6 MWO |
704 | if (folio_test_swapcache(folio) || folio_test_dirty(folio)) { |
705 | if (!folio_trylock(folio)) | |
854e9ed0 MK |
706 | continue; |
707 | /* | |
98b211d6 MWO |
708 | * If folio is shared with others, we mustn't clear |
709 | * the folio's dirty flag. | |
854e9ed0 | 710 | */ |
98b211d6 MWO |
711 | if (folio_mapcount(folio) != 1) { |
712 | folio_unlock(folio); | |
854e9ed0 MK |
713 | continue; |
714 | } | |
715 | ||
98b211d6 MWO |
716 | if (folio_test_swapcache(folio) && |
717 | !folio_free_swap(folio)) { | |
718 | folio_unlock(folio); | |
854e9ed0 MK |
719 | continue; |
720 | } | |
721 | ||
98b211d6 MWO |
722 | folio_clear_dirty(folio); |
723 | folio_unlock(folio); | |
854e9ed0 MK |
724 | } |
725 | ||
726 | if (pte_young(ptent) || pte_dirty(ptent)) { | |
727 | /* | |
728 | * Some of architecture(ex, PPC) don't update TLB | |
729 | * with set_pte_at and tlb_remove_tlb_entry so for | |
730 | * the portability, remap the pte with old|clean | |
731 | * after pte clearing. | |
732 | */ | |
733 | ptent = ptep_get_and_clear_full(mm, addr, pte, | |
734 | tlb->fullmm); | |
735 | ||
736 | ptent = pte_mkold(ptent); | |
737 | ptent = pte_mkclean(ptent); | |
738 | set_pte_at(mm, addr, pte, ptent); | |
739 | tlb_remove_tlb_entry(tlb, pte, addr); | |
740 | } | |
6a6fe9eb | 741 | folio_mark_lazyfree(folio); |
854e9ed0 | 742 | } |
f3cd4ab0 | 743 | |
64b42bc1 MK |
744 | if (nr_swap) { |
745 | if (current->mm == mm) | |
746 | sync_mm_rss(mm); | |
64b42bc1 MK |
747 | add_mm_counter(mm, MM_SWAPENTS, nr_swap); |
748 | } | |
f3cd4ab0 HD |
749 | if (start_pte) { |
750 | arch_leave_lazy_mmu_mode(); | |
751 | pte_unmap_unlock(start_pte, ptl); | |
752 | } | |
854e9ed0 | 753 | cond_resched(); |
f3cd4ab0 | 754 | |
854e9ed0 MK |
755 | return 0; |
756 | } | |
757 | ||
7b86ac33 CH |
758 | static const struct mm_walk_ops madvise_free_walk_ops = { |
759 | .pmd_entry = madvise_free_pte_range, | |
760 | }; | |
854e9ed0 MK |
761 | |
762 | static int madvise_free_single_vma(struct vm_area_struct *vma, | |
763 | unsigned long start_addr, unsigned long end_addr) | |
764 | { | |
854e9ed0 | 765 | struct mm_struct *mm = vma->vm_mm; |
ac46d4f3 | 766 | struct mmu_notifier_range range; |
854e9ed0 MK |
767 | struct mmu_gather tlb; |
768 | ||
854e9ed0 MK |
769 | /* MADV_FREE works for only anon vma at the moment */ |
770 | if (!vma_is_anonymous(vma)) | |
771 | return -EINVAL; | |
772 | ||
ac46d4f3 JG |
773 | range.start = max(vma->vm_start, start_addr); |
774 | if (range.start >= vma->vm_end) | |
854e9ed0 | 775 | return -EINVAL; |
ac46d4f3 JG |
776 | range.end = min(vma->vm_end, end_addr); |
777 | if (range.end <= vma->vm_start) | |
854e9ed0 | 778 | return -EINVAL; |
7d4a8be0 | 779 | mmu_notifier_range_init(&range, MMU_NOTIFY_CLEAR, 0, mm, |
6f4f13e8 | 780 | range.start, range.end); |
854e9ed0 MK |
781 | |
782 | lru_add_drain(); | |
a72afd87 | 783 | tlb_gather_mmu(&tlb, mm); |
854e9ed0 MK |
784 | update_hiwater_rss(mm); |
785 | ||
ac46d4f3 | 786 | mmu_notifier_invalidate_range_start(&range); |
7b86ac33 CH |
787 | tlb_start_vma(&tlb, vma); |
788 | walk_page_range(vma->vm_mm, range.start, range.end, | |
789 | &madvise_free_walk_ops, &tlb); | |
790 | tlb_end_vma(&tlb, vma); | |
ac46d4f3 | 791 | mmu_notifier_invalidate_range_end(&range); |
ae8eba8b | 792 | tlb_finish_mmu(&tlb); |
854e9ed0 MK |
793 | |
794 | return 0; | |
795 | } | |
796 | ||
1da177e4 LT |
797 | /* |
798 | * Application no longer needs these pages. If the pages are dirty, | |
799 | * it's OK to just throw them away. The app will be more careful about | |
800 | * data it wants to keep. Be sure to free swap resources too. The | |
21b85b09 MK |
801 | * zap_page_range_single call sets things up for shrink_active_list to actually |
802 | * free these pages later if no one else has touched them in the meantime, | |
1da177e4 | 803 | * although we could add these pages to a global reuse list for |
7e6cbea3 | 804 | * shrink_active_list to pick up before reclaiming other pages. |
1da177e4 LT |
805 | * |
806 | * NB: This interface discards data rather than pushes it out to swap, | |
807 | * as some implementations do. This has performance implications for | |
808 | * applications like large transactional databases which want to discard | |
809 | * pages in anonymous maps after committing to backing store the data | |
810 | * that was kept in them. There is no reason to write this data out to | |
811 | * the swap area if the application is discarding it. | |
812 | * | |
813 | * An interface that causes the system to free clean pages and flush | |
814 | * dirty pages is already available as msync(MS_INVALIDATE). | |
815 | */ | |
230ca982 MR |
816 | static long madvise_dontneed_single_vma(struct vm_area_struct *vma, |
817 | unsigned long start, unsigned long end) | |
818 | { | |
21b85b09 | 819 | zap_page_range_single(vma, start, end - start, NULL); |
230ca982 MR |
820 | return 0; |
821 | } | |
822 | ||
90e7e7f5 MK |
823 | static bool madvise_dontneed_free_valid_vma(struct vm_area_struct *vma, |
824 | unsigned long start, | |
825 | unsigned long *end, | |
826 | int behavior) | |
827 | { | |
9457056a JW |
828 | if (!is_vm_hugetlb_page(vma)) { |
829 | unsigned int forbidden = VM_PFNMAP; | |
830 | ||
831 | if (behavior != MADV_DONTNEED_LOCKED) | |
832 | forbidden |= VM_LOCKED; | |
833 | ||
834 | return !(vma->vm_flags & forbidden); | |
835 | } | |
90e7e7f5 | 836 | |
9457056a | 837 | if (behavior != MADV_DONTNEED && behavior != MADV_DONTNEED_LOCKED) |
90e7e7f5 MK |
838 | return false; |
839 | if (start & ~huge_page_mask(hstate_vma(vma))) | |
840 | return false; | |
841 | ||
8ebe0a5e RR |
842 | /* |
843 | * Madvise callers expect the length to be rounded up to PAGE_SIZE | |
844 | * boundaries, and may be unaware that this VMA uses huge pages. | |
845 | * Avoid unexpected data loss by rounding down the number of | |
846 | * huge pages freed. | |
847 | */ | |
848 | *end = ALIGN_DOWN(*end, huge_page_size(hstate_vma(vma))); | |
849 | ||
90e7e7f5 MK |
850 | return true; |
851 | } | |
852 | ||
230ca982 MR |
853 | static long madvise_dontneed_free(struct vm_area_struct *vma, |
854 | struct vm_area_struct **prev, | |
855 | unsigned long start, unsigned long end, | |
856 | int behavior) | |
1da177e4 | 857 | { |
0726b01e MK |
858 | struct mm_struct *mm = vma->vm_mm; |
859 | ||
05b74384 | 860 | *prev = vma; |
90e7e7f5 | 861 | if (!madvise_dontneed_free_valid_vma(vma, start, &end, behavior)) |
1da177e4 LT |
862 | return -EINVAL; |
863 | ||
8ebe0a5e RR |
864 | if (start == end) |
865 | return 0; | |
866 | ||
70ccb92f | 867 | if (!userfaultfd_remove(vma, start, end)) { |
c1e8d7c6 | 868 | *prev = NULL; /* mmap_lock has been dropped, prev is stale */ |
70ccb92f | 869 | |
0726b01e | 870 | mmap_read_lock(mm); |
92d5df38 | 871 | vma = vma_lookup(mm, start); |
70ccb92f AA |
872 | if (!vma) |
873 | return -ENOMEM; | |
90e7e7f5 MK |
874 | /* |
875 | * Potential end adjustment for hugetlb vma is OK as | |
876 | * the check below keeps end within vma. | |
877 | */ | |
878 | if (!madvise_dontneed_free_valid_vma(vma, start, &end, | |
879 | behavior)) | |
70ccb92f AA |
880 | return -EINVAL; |
881 | if (end > vma->vm_end) { | |
882 | /* | |
883 | * Don't fail if end > vma->vm_end. If the old | |
f0953a1b | 884 | * vma was split while the mmap_lock was |
70ccb92f | 885 | * released the effect of the concurrent |
230ca982 | 886 | * operation may not cause madvise() to |
70ccb92f AA |
887 | * have an undefined result. There may be an |
888 | * adjacent next vma that we'll walk | |
889 | * next. userfaultfd_remove() will generate an | |
890 | * UFFD_EVENT_REMOVE repetition on the | |
891 | * end-vma->vm_end range, but the manager can | |
892 | * handle a repetition fine. | |
893 | */ | |
894 | end = vma->vm_end; | |
895 | } | |
896 | VM_WARN_ON(start >= end); | |
897 | } | |
230ca982 | 898 | |
9457056a | 899 | if (behavior == MADV_DONTNEED || behavior == MADV_DONTNEED_LOCKED) |
230ca982 MR |
900 | return madvise_dontneed_single_vma(vma, start, end); |
901 | else if (behavior == MADV_FREE) | |
902 | return madvise_free_single_vma(vma, start, end); | |
903 | else | |
904 | return -EINVAL; | |
1da177e4 LT |
905 | } |
906 | ||
4ca9b385 DH |
907 | static long madvise_populate(struct vm_area_struct *vma, |
908 | struct vm_area_struct **prev, | |
909 | unsigned long start, unsigned long end, | |
910 | int behavior) | |
911 | { | |
912 | const bool write = behavior == MADV_POPULATE_WRITE; | |
913 | struct mm_struct *mm = vma->vm_mm; | |
914 | unsigned long tmp_end; | |
915 | int locked = 1; | |
916 | long pages; | |
917 | ||
918 | *prev = vma; | |
919 | ||
920 | while (start < end) { | |
921 | /* | |
922 | * We might have temporarily dropped the lock. For example, | |
923 | * our VMA might have been split. | |
924 | */ | |
925 | if (!vma || start >= vma->vm_end) { | |
531037a0 ML |
926 | vma = vma_lookup(mm, start); |
927 | if (!vma) | |
4ca9b385 DH |
928 | return -ENOMEM; |
929 | } | |
930 | ||
931 | tmp_end = min_t(unsigned long, end, vma->vm_end); | |
932 | /* Populate (prefault) page tables readable/writable. */ | |
933 | pages = faultin_vma_page_range(vma, start, tmp_end, write, | |
934 | &locked); | |
935 | if (!locked) { | |
936 | mmap_read_lock(mm); | |
937 | locked = 1; | |
938 | *prev = NULL; | |
939 | vma = NULL; | |
940 | } | |
941 | if (pages < 0) { | |
942 | switch (pages) { | |
943 | case -EINTR: | |
944 | return -EINTR; | |
eb2faa51 | 945 | case -EINVAL: /* Incompatible mappings / permissions. */ |
4ca9b385 DH |
946 | return -EINVAL; |
947 | case -EHWPOISON: | |
948 | return -EHWPOISON; | |
eb2faa51 DH |
949 | case -EFAULT: /* VM_FAULT_SIGBUS or VM_FAULT_SIGSEGV */ |
950 | return -EFAULT; | |
4ca9b385 DH |
951 | default: |
952 | pr_warn_once("%s: unhandled return value: %ld\n", | |
953 | __func__, pages); | |
954 | fallthrough; | |
955 | case -ENOMEM: | |
956 | return -ENOMEM; | |
957 | } | |
958 | } | |
959 | start += pages * PAGE_SIZE; | |
960 | } | |
961 | return 0; | |
962 | } | |
963 | ||
f6b3ec23 BP |
964 | /* |
965 | * Application wants to free up the pages and associated backing store. | |
966 | * This is effectively punching a hole into the middle of a file. | |
f6b3ec23 BP |
967 | */ |
968 | static long madvise_remove(struct vm_area_struct *vma, | |
00e9fa2d | 969 | struct vm_area_struct **prev, |
f6b3ec23 BP |
970 | unsigned long start, unsigned long end) |
971 | { | |
3f31d075 | 972 | loff_t offset; |
90ed52eb | 973 | int error; |
9ab4233d | 974 | struct file *f; |
0726b01e | 975 | struct mm_struct *mm = vma->vm_mm; |
f6b3ec23 | 976 | |
c1e8d7c6 | 977 | *prev = NULL; /* tell sys_madvise we drop mmap_lock */ |
00e9fa2d | 978 | |
72079ba0 | 979 | if (vma->vm_flags & VM_LOCKED) |
f6b3ec23 BP |
980 | return -EINVAL; |
981 | ||
9ab4233d AL |
982 | f = vma->vm_file; |
983 | ||
984 | if (!f || !f->f_mapping || !f->f_mapping->host) { | |
f6b3ec23 BP |
985 | return -EINVAL; |
986 | } | |
987 | ||
69cf0fac HD |
988 | if ((vma->vm_flags & (VM_SHARED|VM_WRITE)) != (VM_SHARED|VM_WRITE)) |
989 | return -EACCES; | |
990 | ||
f6b3ec23 BP |
991 | offset = (loff_t)(start - vma->vm_start) |
992 | + ((loff_t)vma->vm_pgoff << PAGE_SHIFT); | |
90ed52eb | 993 | |
9ab4233d | 994 | /* |
9608703e | 995 | * Filesystem's fallocate may need to take i_rwsem. We need to |
9ab4233d AL |
996 | * explicitly grab a reference because the vma (and hence the |
997 | * vma's reference to the file) can go away as soon as we drop | |
c1e8d7c6 | 998 | * mmap_lock. |
9ab4233d AL |
999 | */ |
1000 | get_file(f); | |
70ccb92f | 1001 | if (userfaultfd_remove(vma, start, end)) { |
c1e8d7c6 | 1002 | /* mmap_lock was not released by userfaultfd_remove() */ |
0726b01e | 1003 | mmap_read_unlock(mm); |
70ccb92f | 1004 | } |
72c72bdf | 1005 | error = vfs_fallocate(f, |
3f31d075 HD |
1006 | FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE, |
1007 | offset, end - start); | |
9ab4233d | 1008 | fput(f); |
0726b01e | 1009 | mmap_read_lock(mm); |
90ed52eb | 1010 | return error; |
f6b3ec23 BP |
1011 | } |
1012 | ||
ac1e9acc CC |
1013 | /* |
1014 | * Apply an madvise behavior to a region of a vma. madvise_update_vma | |
1015 | * will handle splitting a vm area into separate areas, each area with its own | |
1016 | * behavior. | |
1017 | */ | |
1018 | static int madvise_vma_behavior(struct vm_area_struct *vma, | |
1019 | struct vm_area_struct **prev, | |
1020 | unsigned long start, unsigned long end, | |
1021 | unsigned long behavior) | |
1022 | { | |
1023 | int error; | |
942341dc | 1024 | struct anon_vma_name *anon_name; |
ac1e9acc CC |
1025 | unsigned long new_flags = vma->vm_flags; |
1026 | ||
1027 | switch (behavior) { | |
1028 | case MADV_REMOVE: | |
1029 | return madvise_remove(vma, prev, start, end); | |
1030 | case MADV_WILLNEED: | |
1031 | return madvise_willneed(vma, prev, start, end); | |
1032 | case MADV_COLD: | |
1033 | return madvise_cold(vma, prev, start, end); | |
1034 | case MADV_PAGEOUT: | |
1035 | return madvise_pageout(vma, prev, start, end); | |
1036 | case MADV_FREE: | |
1037 | case MADV_DONTNEED: | |
9457056a | 1038 | case MADV_DONTNEED_LOCKED: |
ac1e9acc CC |
1039 | return madvise_dontneed_free(vma, prev, start, end, behavior); |
1040 | case MADV_POPULATE_READ: | |
1041 | case MADV_POPULATE_WRITE: | |
1042 | return madvise_populate(vma, prev, start, end, behavior); | |
1043 | case MADV_NORMAL: | |
1044 | new_flags = new_flags & ~VM_RAND_READ & ~VM_SEQ_READ; | |
1045 | break; | |
1046 | case MADV_SEQUENTIAL: | |
1047 | new_flags = (new_flags & ~VM_RAND_READ) | VM_SEQ_READ; | |
1048 | break; | |
1049 | case MADV_RANDOM: | |
1050 | new_flags = (new_flags & ~VM_SEQ_READ) | VM_RAND_READ; | |
1051 | break; | |
1052 | case MADV_DONTFORK: | |
1053 | new_flags |= VM_DONTCOPY; | |
1054 | break; | |
1055 | case MADV_DOFORK: | |
1056 | if (vma->vm_flags & VM_IO) | |
1057 | return -EINVAL; | |
1058 | new_flags &= ~VM_DONTCOPY; | |
1059 | break; | |
1060 | case MADV_WIPEONFORK: | |
1061 | /* MADV_WIPEONFORK is only supported on anonymous memory. */ | |
1062 | if (vma->vm_file || vma->vm_flags & VM_SHARED) | |
1063 | return -EINVAL; | |
1064 | new_flags |= VM_WIPEONFORK; | |
1065 | break; | |
1066 | case MADV_KEEPONFORK: | |
1067 | new_flags &= ~VM_WIPEONFORK; | |
1068 | break; | |
1069 | case MADV_DONTDUMP: | |
1070 | new_flags |= VM_DONTDUMP; | |
1071 | break; | |
1072 | case MADV_DODUMP: | |
1073 | if (!is_vm_hugetlb_page(vma) && new_flags & VM_SPECIAL) | |
1074 | return -EINVAL; | |
1075 | new_flags &= ~VM_DONTDUMP; | |
1076 | break; | |
1077 | case MADV_MERGEABLE: | |
1078 | case MADV_UNMERGEABLE: | |
1079 | error = ksm_madvise(vma, start, end, behavior, &new_flags); | |
1080 | if (error) | |
1081 | goto out; | |
1082 | break; | |
1083 | case MADV_HUGEPAGE: | |
1084 | case MADV_NOHUGEPAGE: | |
1085 | error = hugepage_madvise(vma, &new_flags, behavior); | |
1086 | if (error) | |
1087 | goto out; | |
1088 | break; | |
7d8faaf1 ZK |
1089 | case MADV_COLLAPSE: |
1090 | return madvise_collapse(vma, prev, start, end); | |
ac1e9acc CC |
1091 | } |
1092 | ||
942341dc SB |
1093 | anon_name = anon_vma_name(vma); |
1094 | anon_vma_name_get(anon_name); | |
9a10064f | 1095 | error = madvise_update_vma(vma, prev, start, end, new_flags, |
942341dc SB |
1096 | anon_name); |
1097 | anon_vma_name_put(anon_name); | |
ac1e9acc CC |
1098 | |
1099 | out: | |
1100 | /* | |
1101 | * madvise() returns EAGAIN if kernel resources, such as | |
1102 | * slab, are temporarily unavailable. | |
1103 | */ | |
1104 | if (error == -ENOMEM) | |
1105 | error = -EAGAIN; | |
1106 | return error; | |
1107 | } | |
1108 | ||
9893e49d AK |
1109 | #ifdef CONFIG_MEMORY_FAILURE |
1110 | /* | |
1111 | * Error injection support for memory error handling. | |
1112 | */ | |
97167a76 AK |
1113 | static int madvise_inject_error(int behavior, |
1114 | unsigned long start, unsigned long end) | |
9893e49d | 1115 | { |
d3cd257c | 1116 | unsigned long size; |
97167a76 | 1117 | |
9893e49d AK |
1118 | if (!capable(CAP_SYS_ADMIN)) |
1119 | return -EPERM; | |
97167a76 | 1120 | |
19bfbe22 | 1121 | |
d3cd257c | 1122 | for (; start < end; start += size) { |
23e7b5c2 | 1123 | unsigned long pfn; |
dc7560b4 | 1124 | struct page *page; |
325c4ef5 AM |
1125 | int ret; |
1126 | ||
97167a76 | 1127 | ret = get_user_pages_fast(start, 1, 0, &page); |
9893e49d AK |
1128 | if (ret != 1) |
1129 | return ret; | |
23e7b5c2 | 1130 | pfn = page_to_pfn(page); |
325c4ef5 | 1131 | |
19bfbe22 AM |
1132 | /* |
1133 | * When soft offlining hugepages, after migrating the page | |
1134 | * we dissolve it, therefore in the second loop "page" will | |
d3cd257c | 1135 | * no longer be a compound page. |
19bfbe22 | 1136 | */ |
d3cd257c | 1137 | size = page_size(compound_head(page)); |
19bfbe22 | 1138 | |
97167a76 AK |
1139 | if (behavior == MADV_SOFT_OFFLINE) { |
1140 | pr_info("Soft offlining pfn %#lx at process virtual address %#lx\n", | |
dc7560b4 | 1141 | pfn, start); |
feec24a6 | 1142 | ret = soft_offline_page(pfn, MF_COUNT_INCREASED); |
dc7560b4 OS |
1143 | } else { |
1144 | pr_info("Injecting memory failure for pfn %#lx at process virtual address %#lx\n", | |
1145 | pfn, start); | |
67f22ba7 | 1146 | ret = memory_failure(pfn, MF_COUNT_INCREASED | MF_SW_SIMULATED); |
d1fe111f | 1147 | if (ret == -EOPNOTSUPP) |
1148 | ret = 0; | |
afcf938e | 1149 | } |
23e7b5c2 | 1150 | |
23a003bf NH |
1151 | if (ret) |
1152 | return ret; | |
9893e49d | 1153 | } |
c461ad6a | 1154 | |
325c4ef5 | 1155 | return 0; |
9893e49d AK |
1156 | } |
1157 | #endif | |
1158 | ||
1ecef9ed | 1159 | static bool |
75927af8 NP |
1160 | madvise_behavior_valid(int behavior) |
1161 | { | |
1162 | switch (behavior) { | |
1163 | case MADV_DOFORK: | |
1164 | case MADV_DONTFORK: | |
1165 | case MADV_NORMAL: | |
1166 | case MADV_SEQUENTIAL: | |
1167 | case MADV_RANDOM: | |
1168 | case MADV_REMOVE: | |
1169 | case MADV_WILLNEED: | |
1170 | case MADV_DONTNEED: | |
9457056a | 1171 | case MADV_DONTNEED_LOCKED: |
854e9ed0 | 1172 | case MADV_FREE: |
9c276cc6 | 1173 | case MADV_COLD: |
1a4e58cc | 1174 | case MADV_PAGEOUT: |
4ca9b385 DH |
1175 | case MADV_POPULATE_READ: |
1176 | case MADV_POPULATE_WRITE: | |
f8af4da3 HD |
1177 | #ifdef CONFIG_KSM |
1178 | case MADV_MERGEABLE: | |
1179 | case MADV_UNMERGEABLE: | |
0af4e98b AA |
1180 | #endif |
1181 | #ifdef CONFIG_TRANSPARENT_HUGEPAGE | |
1182 | case MADV_HUGEPAGE: | |
a664b2d8 | 1183 | case MADV_NOHUGEPAGE: |
7d8faaf1 | 1184 | case MADV_COLLAPSE: |
f8af4da3 | 1185 | #endif |
accb61fe JB |
1186 | case MADV_DONTDUMP: |
1187 | case MADV_DODUMP: | |
d2cd9ede RR |
1188 | case MADV_WIPEONFORK: |
1189 | case MADV_KEEPONFORK: | |
5e451be7 AK |
1190 | #ifdef CONFIG_MEMORY_FAILURE |
1191 | case MADV_SOFT_OFFLINE: | |
1192 | case MADV_HWPOISON: | |
1193 | #endif | |
1ecef9ed | 1194 | return true; |
75927af8 NP |
1195 | |
1196 | default: | |
1ecef9ed | 1197 | return false; |
75927af8 NP |
1198 | } |
1199 | } | |
3866ea90 | 1200 | |
876b4a18 | 1201 | static bool process_madvise_behavior_valid(int behavior) |
ecb8ac8b MK |
1202 | { |
1203 | switch (behavior) { | |
1204 | case MADV_COLD: | |
1205 | case MADV_PAGEOUT: | |
d5fffc5a | 1206 | case MADV_WILLNEED: |
876b4a18 | 1207 | case MADV_COLLAPSE: |
ecb8ac8b MK |
1208 | return true; |
1209 | default: | |
1210 | return false; | |
1211 | } | |
1212 | } | |
1213 | ||
ac1e9acc CC |
1214 | /* |
1215 | * Walk the vmas in range [start,end), and call the visit function on each one. | |
1216 | * The visit function will get start and end parameters that cover the overlap | |
1217 | * between the current vma and the original range. Any unmapped regions in the | |
1218 | * original range will result in this function returning -ENOMEM while still | |
1219 | * calling the visit function on all of the existing vmas in the range. | |
1220 | * Must be called with the mmap_lock held for reading or writing. | |
1221 | */ | |
1222 | static | |
1223 | int madvise_walk_vmas(struct mm_struct *mm, unsigned long start, | |
1224 | unsigned long end, unsigned long arg, | |
1225 | int (*visit)(struct vm_area_struct *vma, | |
1226 | struct vm_area_struct **prev, unsigned long start, | |
1227 | unsigned long end, unsigned long arg)) | |
1228 | { | |
1229 | struct vm_area_struct *vma; | |
1230 | struct vm_area_struct *prev; | |
1231 | unsigned long tmp; | |
1232 | int unmapped_error = 0; | |
1233 | ||
1234 | /* | |
1235 | * If the interval [start,end) covers some unmapped address | |
1236 | * ranges, just ignore them, but return -ENOMEM at the end. | |
1237 | * - different from the way of handling in mlock etc. | |
1238 | */ | |
1239 | vma = find_vma_prev(mm, start, &prev); | |
1240 | if (vma && start > vma->vm_start) | |
1241 | prev = vma; | |
1242 | ||
1243 | for (;;) { | |
1244 | int error; | |
1245 | ||
1246 | /* Still start < end. */ | |
1247 | if (!vma) | |
1248 | return -ENOMEM; | |
1249 | ||
1250 | /* Here start < (end|vma->vm_end). */ | |
1251 | if (start < vma->vm_start) { | |
1252 | unmapped_error = -ENOMEM; | |
1253 | start = vma->vm_start; | |
1254 | if (start >= end) | |
1255 | break; | |
1256 | } | |
1257 | ||
1258 | /* Here vma->vm_start <= start < (end|vma->vm_end) */ | |
1259 | tmp = vma->vm_end; | |
1260 | if (end < tmp) | |
1261 | tmp = end; | |
1262 | ||
1263 | /* Here vma->vm_start <= start < tmp <= (end|vma->vm_end). */ | |
1264 | error = visit(vma, &prev, start, tmp, arg); | |
1265 | if (error) | |
1266 | return error; | |
1267 | start = tmp; | |
1268 | if (prev && start < prev->vm_end) | |
1269 | start = prev->vm_end; | |
1270 | if (start >= end) | |
1271 | break; | |
1272 | if (prev) | |
35474818 | 1273 | vma = find_vma(mm, prev->vm_end); |
ac1e9acc CC |
1274 | else /* madvise_remove dropped mmap_lock */ |
1275 | vma = find_vma(mm, start); | |
1276 | } | |
1277 | ||
1278 | return unmapped_error; | |
1279 | } | |
1280 | ||
9a10064f CC |
1281 | #ifdef CONFIG_ANON_VMA_NAME |
1282 | static int madvise_vma_anon_name(struct vm_area_struct *vma, | |
1283 | struct vm_area_struct **prev, | |
1284 | unsigned long start, unsigned long end, | |
5c26f6ac | 1285 | unsigned long anon_name) |
9a10064f CC |
1286 | { |
1287 | int error; | |
1288 | ||
1289 | /* Only anonymous mappings can be named */ | |
d09e8ca6 | 1290 | if (vma->vm_file && !vma_is_anon_shmem(vma)) |
9a10064f CC |
1291 | return -EBADF; |
1292 | ||
1293 | error = madvise_update_vma(vma, prev, start, end, vma->vm_flags, | |
5c26f6ac | 1294 | (struct anon_vma_name *)anon_name); |
9a10064f CC |
1295 | |
1296 | /* | |
1297 | * madvise() returns EAGAIN if kernel resources, such as | |
1298 | * slab, are temporarily unavailable. | |
1299 | */ | |
1300 | if (error == -ENOMEM) | |
1301 | error = -EAGAIN; | |
1302 | return error; | |
1303 | } | |
1304 | ||
1305 | int madvise_set_anon_name(struct mm_struct *mm, unsigned long start, | |
5c26f6ac | 1306 | unsigned long len_in, struct anon_vma_name *anon_name) |
9a10064f CC |
1307 | { |
1308 | unsigned long end; | |
1309 | unsigned long len; | |
1310 | ||
1311 | if (start & ~PAGE_MASK) | |
1312 | return -EINVAL; | |
1313 | len = (len_in + ~PAGE_MASK) & PAGE_MASK; | |
1314 | ||
1315 | /* Check to see whether len was rounded up from small -ve to zero */ | |
1316 | if (len_in && !len) | |
1317 | return -EINVAL; | |
1318 | ||
1319 | end = start + len; | |
1320 | if (end < start) | |
1321 | return -EINVAL; | |
1322 | ||
1323 | if (end == start) | |
1324 | return 0; | |
1325 | ||
5c26f6ac | 1326 | return madvise_walk_vmas(mm, start, end, (unsigned long)anon_name, |
9a10064f CC |
1327 | madvise_vma_anon_name); |
1328 | } | |
1329 | #endif /* CONFIG_ANON_VMA_NAME */ | |
1da177e4 LT |
1330 | /* |
1331 | * The madvise(2) system call. | |
1332 | * | |
1333 | * Applications can use madvise() to advise the kernel how it should | |
1334 | * handle paging I/O in this VM area. The idea is to help the kernel | |
1335 | * use appropriate read-ahead and caching techniques. The information | |
1336 | * provided is advisory only, and can be safely disregarded by the | |
1337 | * kernel without affecting the correct operation of the application. | |
1338 | * | |
1339 | * behavior values: | |
1340 | * MADV_NORMAL - the default behavior is to read clusters. This | |
1341 | * results in some read-ahead and read-behind. | |
1342 | * MADV_RANDOM - the system should read the minimum amount of data | |
1343 | * on any access, since it is unlikely that the appli- | |
1344 | * cation will need more than what it asks for. | |
1345 | * MADV_SEQUENTIAL - pages in the given range will probably be accessed | |
1346 | * once, so they can be aggressively read ahead, and | |
1347 | * can be freed soon after they are accessed. | |
1348 | * MADV_WILLNEED - the application is notifying the system to read | |
1349 | * some pages ahead. | |
1350 | * MADV_DONTNEED - the application is finished with the given range, | |
1351 | * so the kernel can free resources associated with it. | |
d7206a70 NH |
1352 | * MADV_FREE - the application marks pages in the given range as lazy free, |
1353 | * where actual purges are postponed until memory pressure happens. | |
f6b3ec23 BP |
1354 | * MADV_REMOVE - the application wants to free up the given range of |
1355 | * pages and associated backing store. | |
3866ea90 HD |
1356 | * MADV_DONTFORK - omit this area from child's address space when forking: |
1357 | * typically, to avoid COWing pages pinned by get_user_pages(). | |
1358 | * MADV_DOFORK - cancel MADV_DONTFORK: no longer omit this area when forking. | |
c02c3009 YS |
1359 | * MADV_WIPEONFORK - present the child process with zero-filled memory in this |
1360 | * range after a fork. | |
1361 | * MADV_KEEPONFORK - undo the effect of MADV_WIPEONFORK | |
d7206a70 NH |
1362 | * MADV_HWPOISON - trigger memory error handler as if the given memory range |
1363 | * were corrupted by unrecoverable hardware memory failure. | |
1364 | * MADV_SOFT_OFFLINE - try to soft-offline the given range of memory. | |
f8af4da3 HD |
1365 | * MADV_MERGEABLE - the application recommends that KSM try to merge pages in |
1366 | * this area with pages of identical content from other such areas. | |
1367 | * MADV_UNMERGEABLE- cancel MADV_MERGEABLE: no longer merge pages with others. | |
d7206a70 NH |
1368 | * MADV_HUGEPAGE - the application wants to back the given range by transparent |
1369 | * huge pages in the future. Existing pages might be coalesced and | |
1370 | * new pages might be allocated as THP. | |
1371 | * MADV_NOHUGEPAGE - mark the given range as not worth being backed by | |
1372 | * transparent huge pages so the existing pages will not be | |
1373 | * coalesced into THP and new pages will not be allocated as THP. | |
7d8faaf1 | 1374 | * MADV_COLLAPSE - synchronously coalesce pages into new THP. |
d7206a70 NH |
1375 | * MADV_DONTDUMP - the application wants to prevent pages in the given range |
1376 | * from being included in its core dump. | |
1377 | * MADV_DODUMP - cancel MADV_DONTDUMP: no longer exclude from core dump. | |
ecb8ac8b MK |
1378 | * MADV_COLD - the application is not expected to use this memory soon, |
1379 | * deactivate pages in this range so that they can be reclaimed | |
f0953a1b | 1380 | * easily if memory pressure happens. |
ecb8ac8b MK |
1381 | * MADV_PAGEOUT - the application is not expected to use this memory soon, |
1382 | * page out the pages in this range immediately. | |
4ca9b385 DH |
1383 | * MADV_POPULATE_READ - populate (prefault) page tables readable by |
1384 | * triggering read faults if required | |
1385 | * MADV_POPULATE_WRITE - populate (prefault) page tables writable by | |
1386 | * triggering write faults if required | |
1da177e4 LT |
1387 | * |
1388 | * return values: | |
1389 | * zero - success | |
1390 | * -EINVAL - start + len < 0, start is not page-aligned, | |
1391 | * "behavior" is not a valid value, or application | |
c02c3009 YS |
1392 | * is attempting to release locked or shared pages, |
1393 | * or the specified address range includes file, Huge TLB, | |
1394 | * MAP_SHARED or VMPFNMAP range. | |
1da177e4 LT |
1395 | * -ENOMEM - addresses in the specified range are not currently |
1396 | * mapped, or are outside the AS of the process. | |
1397 | * -EIO - an I/O error occurred while paging in data. | |
1398 | * -EBADF - map exists, but area maps something that isn't a file. | |
1399 | * -EAGAIN - a kernel resource was temporarily unavailable. | |
1400 | */ | |
0726b01e | 1401 | int do_madvise(struct mm_struct *mm, unsigned long start, size_t len_in, int behavior) |
1da177e4 | 1402 | { |
ac1e9acc CC |
1403 | unsigned long end; |
1404 | int error; | |
f7977793 | 1405 | int write; |
1da177e4 | 1406 | size_t len; |
1998cc04 | 1407 | struct blk_plug plug; |
1da177e4 | 1408 | |
75927af8 | 1409 | if (!madvise_behavior_valid(behavior)) |
ac1e9acc | 1410 | return -EINVAL; |
75927af8 | 1411 | |
df6c6500 | 1412 | if (!PAGE_ALIGNED(start)) |
ac1e9acc | 1413 | return -EINVAL; |
df6c6500 | 1414 | len = PAGE_ALIGN(len_in); |
1da177e4 LT |
1415 | |
1416 | /* Check to see whether len was rounded up from small -ve to zero */ | |
1417 | if (len_in && !len) | |
ac1e9acc | 1418 | return -EINVAL; |
1da177e4 LT |
1419 | |
1420 | end = start + len; | |
1421 | if (end < start) | |
ac1e9acc | 1422 | return -EINVAL; |
1da177e4 | 1423 | |
1da177e4 | 1424 | if (end == start) |
ac1e9acc | 1425 | return 0; |
84d96d89 | 1426 | |
5e451be7 AK |
1427 | #ifdef CONFIG_MEMORY_FAILURE |
1428 | if (behavior == MADV_HWPOISON || behavior == MADV_SOFT_OFFLINE) | |
1429 | return madvise_inject_error(behavior, start, start + len_in); | |
1430 | #endif | |
1431 | ||
84d96d89 | 1432 | write = madvise_need_mmap_write(behavior); |
dc0ef0df | 1433 | if (write) { |
0726b01e | 1434 | if (mmap_write_lock_killable(mm)) |
dc0ef0df MH |
1435 | return -EINTR; |
1436 | } else { | |
0726b01e | 1437 | mmap_read_lock(mm); |
dc0ef0df | 1438 | } |
1da177e4 | 1439 | |
428e106a KS |
1440 | start = untagged_addr_remote(mm, start); |
1441 | end = start + len; | |
1442 | ||
1998cc04 | 1443 | blk_start_plug(&plug); |
ac1e9acc CC |
1444 | error = madvise_walk_vmas(mm, start, end, behavior, |
1445 | madvise_vma_behavior); | |
84d96d89 | 1446 | blk_finish_plug(&plug); |
f7977793 | 1447 | if (write) |
0726b01e | 1448 | mmap_write_unlock(mm); |
0a27a14a | 1449 | else |
0726b01e | 1450 | mmap_read_unlock(mm); |
0a27a14a | 1451 | |
1da177e4 LT |
1452 | return error; |
1453 | } | |
db08ca25 JA |
1454 | |
1455 | SYSCALL_DEFINE3(madvise, unsigned long, start, size_t, len_in, int, behavior) | |
1456 | { | |
0726b01e | 1457 | return do_madvise(current->mm, start, len_in, behavior); |
db08ca25 | 1458 | } |
ecb8ac8b MK |
1459 | |
1460 | SYSCALL_DEFINE5(process_madvise, int, pidfd, const struct iovec __user *, vec, | |
1461 | size_t, vlen, int, behavior, unsigned int, flags) | |
1462 | { | |
1463 | ssize_t ret; | |
95e49cf8 | 1464 | struct iovec iovstack[UIO_FASTIOV]; |
ecb8ac8b MK |
1465 | struct iovec *iov = iovstack; |
1466 | struct iov_iter iter; | |
ecb8ac8b MK |
1467 | struct task_struct *task; |
1468 | struct mm_struct *mm; | |
1469 | size_t total_len; | |
1470 | unsigned int f_flags; | |
1471 | ||
1472 | if (flags != 0) { | |
1473 | ret = -EINVAL; | |
1474 | goto out; | |
1475 | } | |
1476 | ||
de4eda9d | 1477 | ret = import_iovec(ITER_DEST, vec, vlen, ARRAY_SIZE(iovstack), &iov, &iter); |
ecb8ac8b MK |
1478 | if (ret < 0) |
1479 | goto out; | |
1480 | ||
ee9955d6 CB |
1481 | task = pidfd_get_task(pidfd, &f_flags); |
1482 | if (IS_ERR(task)) { | |
1483 | ret = PTR_ERR(task); | |
ecb8ac8b MK |
1484 | goto free_iov; |
1485 | } | |
1486 | ||
a68a0262 | 1487 | if (!process_madvise_behavior_valid(behavior)) { |
ecb8ac8b MK |
1488 | ret = -EINVAL; |
1489 | goto release_task; | |
1490 | } | |
1491 | ||
96cfe2c0 SB |
1492 | /* Require PTRACE_MODE_READ to avoid leaking ASLR metadata. */ |
1493 | mm = mm_access(task, PTRACE_MODE_READ_FSCREDS); | |
ecb8ac8b MK |
1494 | if (IS_ERR_OR_NULL(mm)) { |
1495 | ret = IS_ERR(mm) ? PTR_ERR(mm) : -ESRCH; | |
1496 | goto release_task; | |
1497 | } | |
1498 | ||
96cfe2c0 SB |
1499 | /* |
1500 | * Require CAP_SYS_NICE for influencing process performance. Note that | |
1501 | * only non-destructive hints are currently supported. | |
1502 | */ | |
1503 | if (!capable(CAP_SYS_NICE)) { | |
1504 | ret = -EPERM; | |
1505 | goto release_mm; | |
1506 | } | |
1507 | ||
ecb8ac8b MK |
1508 | total_len = iov_iter_count(&iter); |
1509 | ||
1510 | while (iov_iter_count(&iter)) { | |
95e49cf8 JA |
1511 | ret = do_madvise(mm, (unsigned long)iter_iov_addr(&iter), |
1512 | iter_iov_len(&iter), behavior); | |
e6b0a7b3 | 1513 | if (ret < 0) |
ecb8ac8b | 1514 | break; |
95e49cf8 | 1515 | iov_iter_advance(&iter, iter_iov_len(&iter)); |
ecb8ac8b MK |
1516 | } |
1517 | ||
5bd009c7 | 1518 | ret = (total_len - iov_iter_count(&iter)) ? : ret; |
ecb8ac8b | 1519 | |
96cfe2c0 | 1520 | release_mm: |
ecb8ac8b | 1521 | mmput(mm); |
ecb8ac8b MK |
1522 | release_task: |
1523 | put_task_struct(task); | |
ecb8ac8b MK |
1524 | free_iov: |
1525 | kfree(iov); | |
1526 | out: | |
1527 | return ret; | |
1528 | } |