Blame view
mm/madvise.c
22.6 KB
b24413180 License cleanup: ... |
1 |
// SPDX-License-Identifier: GPL-2.0 |
1da177e4c Linux-2.6.12-rc2 |
2 3 4 5 6 7 8 9 10 11 |
/* * linux/mm/madvise.c * * Copyright (C) 1999 Linus Torvalds * Copyright (C) 2002 Christoph Hellwig */ #include <linux/mman.h> #include <linux/pagemap.h> #include <linux/syscalls.h> |
05b743847 [PATCH] madvise: ... |
12 |
#include <linux/mempolicy.h> |
afcf938ee HWPOISON: Add a m... |
13 |
#include <linux/page-isolation.h> |
05ce77249 userfaultfd: non-... |
14 |
#include <linux/userfaultfd_k.h> |
1da177e4c Linux-2.6.12-rc2 |
15 |
#include <linux/hugetlb.h> |
3f31d0757 mm/fs: route MADV... |
16 |
#include <linux/falloc.h> |
e8edc6e03 Detach sched.h fr... |
17 |
#include <linux/sched.h> |
f8af4da3b ksm: the mm inter... |
18 |
#include <linux/ksm.h> |
3f31d0757 mm/fs: route MADV... |
19 |
#include <linux/fs.h> |
9ab4233dd mm: Hold a file r... |
20 |
#include <linux/file.h> |
1998cc048 mm: make madvise(... |
21 |
#include <linux/blkdev.h> |
66114cad6 writeback: separa... |
22 |
#include <linux/backing-dev.h> |
1998cc048 mm: make madvise(... |
23 24 |
#include <linux/swap.h> #include <linux/swapops.h> |
3a4f8a0b3 mm: remove shmem_... |
25 |
#include <linux/shmem_fs.h> |
854e9ed09 mm: support madvi... |
26 27 28 |
#include <linux/mmu_notifier.h> #include <asm/tlb.h> |
1da177e4c Linux-2.6.12-rc2 |
29 |
|
235190738 oom-reaper: use m... |
30 |
#include "internal.h" |
1da177e4c Linux-2.6.12-rc2 |
31 |
/* |
0a27a14a6 mm: madvise avoid... |
32 33 34 35 36 37 38 39 40 41 |
* Any behaviour which results in changes to the vma->vm_flags needs to * take mmap_sem for writing. Others, which simply traverse vmas, need * to only take it for reading. */ static int madvise_need_mmap_write(int behavior) { switch (behavior) { case MADV_REMOVE: case MADV_WILLNEED: case MADV_DONTNEED: |
854e9ed09 mm: support madvi... |
42 |
case MADV_FREE: |
0a27a14a6 mm: madvise avoid... |
43 44 45 46 47 48 49 50 |
return 0; default: /* be safe, default to 1. list exceptions explicitly */ return 1; } } /* |
1da177e4c Linux-2.6.12-rc2 |
51 52 53 |
* We can potentially split a vm area into separate * areas, each area with its own behavior. */ |
ec9bed9d3 mm/madvise.c: fix... |
54 |
static long madvise_behavior(struct vm_area_struct *vma, |
05b743847 [PATCH] madvise: ... |
55 56 |
struct vm_area_struct **prev, unsigned long start, unsigned long end, int behavior) |
1da177e4c Linux-2.6.12-rc2 |
57 |
{ |
ec9bed9d3 mm/madvise.c: fix... |
58 |
struct mm_struct *mm = vma->vm_mm; |
1da177e4c Linux-2.6.12-rc2 |
59 |
int error = 0; |
05b743847 [PATCH] madvise: ... |
60 |
pgoff_t pgoff; |
3866ea90d ksm: first tidy u... |
61 |
unsigned long new_flags = vma->vm_flags; |
e798c6e87 [PATCH] madvise: ... |
62 63 |
switch (behavior) { |
f82256616 [PATCH] madvise M... |
64 65 66 |
case MADV_NORMAL: new_flags = new_flags & ~VM_RAND_READ & ~VM_SEQ_READ; break; |
e798c6e87 [PATCH] madvise: ... |
67 |
case MADV_SEQUENTIAL: |
f82256616 [PATCH] madvise M... |
68 |
new_flags = (new_flags & ~VM_RAND_READ) | VM_SEQ_READ; |
e798c6e87 [PATCH] madvise: ... |
69 70 |
break; case MADV_RANDOM: |
f82256616 [PATCH] madvise M... |
71 |
new_flags = (new_flags & ~VM_SEQ_READ) | VM_RAND_READ; |
e798c6e87 [PATCH] madvise: ... |
72 |
break; |
f82256616 [PATCH] madvise M... |
73 74 75 76 |
case MADV_DONTFORK: new_flags |= VM_DONTCOPY; break; case MADV_DOFORK: |
3866ea90d ksm: first tidy u... |
77 78 79 80 |
if (vma->vm_flags & VM_IO) { error = -EINVAL; goto out; } |
f82256616 [PATCH] madvise M... |
81 |
new_flags &= ~VM_DONTCOPY; |
e798c6e87 [PATCH] madvise: ... |
82 |
break; |
d2cd9ede6 mm,fork: introduc... |
83 84 85 86 87 88 89 90 91 92 93 |
case MADV_WIPEONFORK: /* MADV_WIPEONFORK is only supported on anonymous memory. */ if (vma->vm_file || vma->vm_flags & VM_SHARED) { error = -EINVAL; goto out; } new_flags |= VM_WIPEONFORK; break; case MADV_KEEPONFORK: new_flags &= ~VM_WIPEONFORK; break; |
accb61fe7 coredump: add VM_... |
94 |
case MADV_DONTDUMP: |
0103bd16f mm: prepare VM_DO... |
95 |
new_flags |= VM_DONTDUMP; |
accb61fe7 coredump: add VM_... |
96 97 |
break; case MADV_DODUMP: |
dcc89aaf5 mm: madvise(MADV_... |
98 |
if (!is_vm_hugetlb_page(vma) && new_flags & VM_SPECIAL) { |
0103bd16f mm: prepare VM_DO... |
99 100 101 102 |
error = -EINVAL; goto out; } new_flags &= ~VM_DONTDUMP; |
accb61fe7 coredump: add VM_... |
103 |
break; |
f8af4da3b ksm: the mm inter... |
104 105 106 |
case MADV_MERGEABLE: case MADV_UNMERGEABLE: error = ksm_madvise(vma, start, end, behavior, &new_flags); |
def5efe03 mm, madvise: fail... |
107 108 109 110 111 112 113 |
if (error) { /* * madvise() returns EAGAIN if kernel resources, such as * slab, are temporarily unavailable. */ if (error == -ENOMEM) error = -EAGAIN; |
f8af4da3b ksm: the mm inter... |
114 |
goto out; |
def5efe03 mm, madvise: fail... |
115 |
} |
f8af4da3b ksm: the mm inter... |
116 |
break; |
0af4e98b6 thp: madvise(MADV... |
117 |
case MADV_HUGEPAGE: |
a664b2d85 thp: madvise(MADV... |
118 |
case MADV_NOHUGEPAGE: |
60ab3244e thp: khugepaged: ... |
119 |
error = hugepage_madvise(vma, &new_flags, behavior); |
def5efe03 mm, madvise: fail... |
120 121 122 123 124 125 126 |
if (error) { /* * madvise() returns EAGAIN if kernel resources, such as * slab, are temporarily unavailable. */ if (error == -ENOMEM) error = -EAGAIN; |
0af4e98b6 thp: madvise(MADV... |
127 |
goto out; |
def5efe03 mm, madvise: fail... |
128 |
} |
0af4e98b6 thp: madvise(MADV... |
129 |
break; |
e798c6e87 [PATCH] madvise: ... |
130 |
} |
05b743847 [PATCH] madvise: ... |
131 132 |
if (new_flags == vma->vm_flags) { *prev = vma; |
836d5ffd3 [PATCH] mm: fix m... |
133 |
goto out; |
05b743847 [PATCH] madvise: ... |
134 135 136 137 |
} pgoff = vma->vm_pgoff + ((start - vma->vm_start) >> PAGE_SHIFT); *prev = vma_merge(mm, *prev, start, end, new_flags, vma->anon_vma, |
19a809afe userfaultfd: teac... |
138 139 |
vma->vm_file, pgoff, vma_policy(vma), vma->vm_userfaultfd_ctx); |
05b743847 [PATCH] madvise: ... |
140 141 142 143 144 145 |
if (*prev) { vma = *prev; goto success; } *prev = vma; |
1da177e4c Linux-2.6.12-rc2 |
146 147 |
if (start != vma->vm_start) { |
def5efe03 mm, madvise: fail... |
148 149 |
if (unlikely(mm->map_count >= sysctl_max_map_count)) { error = -ENOMEM; |
1da177e4c Linux-2.6.12-rc2 |
150 |
goto out; |
def5efe03 mm, madvise: fail... |
151 152 153 154 155 156 157 158 159 160 161 |
} error = __split_vma(mm, vma, start, 1); if (error) { /* * madvise() returns EAGAIN if kernel resources, such as * slab, are temporarily unavailable. */ if (error == -ENOMEM) error = -EAGAIN; goto out; } |
1da177e4c Linux-2.6.12-rc2 |
162 163 164 |
} if (end != vma->vm_end) { |
def5efe03 mm, madvise: fail... |
165 166 |
if (unlikely(mm->map_count >= sysctl_max_map_count)) { error = -ENOMEM; |
1da177e4c Linux-2.6.12-rc2 |
167 |
goto out; |
def5efe03 mm, madvise: fail... |
168 169 170 171 172 173 174 175 176 177 178 |
} error = __split_vma(mm, vma, end, 0); if (error) { /* * madvise() returns EAGAIN if kernel resources, such as * slab, are temporarily unavailable. */ if (error == -ENOMEM) error = -EAGAIN; goto out; } |
1da177e4c Linux-2.6.12-rc2 |
179 |
} |
836d5ffd3 [PATCH] mm: fix m... |
180 |
success: |
1da177e4c Linux-2.6.12-rc2 |
181 182 183 |
/* * vm_flags is protected by the mmap_sem held in write mode. */ |
e798c6e87 [PATCH] madvise: ... |
184 |
vma->vm_flags = new_flags; |
1da177e4c Linux-2.6.12-rc2 |
185 |
out: |
1da177e4c Linux-2.6.12-rc2 |
186 187 |
return error; } |
1998cc048 mm: make madvise(... |
188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 |
#ifdef CONFIG_SWAP static int swapin_walk_pmd_entry(pmd_t *pmd, unsigned long start, unsigned long end, struct mm_walk *walk) { pte_t *orig_pte; struct vm_area_struct *vma = walk->private; unsigned long index; if (pmd_none_or_trans_huge_or_clear_bad(pmd)) return 0; for (index = start; index != end; index += PAGE_SIZE) { pte_t pte; swp_entry_t entry; struct page *page; spinlock_t *ptl; orig_pte = pte_offset_map_lock(vma->vm_mm, pmd, start, &ptl); pte = *(orig_pte + ((index - start) / PAGE_SIZE)); pte_unmap_unlock(orig_pte, ptl); |
0661a3361 mm: remove rest u... |
208 |
if (pte_present(pte) || pte_none(pte)) |
1998cc048 mm: make madvise(... |
209 210 211 212 213 214 |
continue; entry = pte_to_swp_entry(pte); if (unlikely(non_swap_entry(entry))) continue; page = read_swap_cache_async(entry, GFP_HIGHUSER_MOVABLE, |
23955622f swap: add block i... |
215 |
vma, index, false); |
1998cc048 mm: make madvise(... |
216 |
if (page) |
09cbfeaf1 mm, fs: get rid o... |
217 |
put_page(page); |
1998cc048 mm: make madvise(... |
218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 |
} return 0; } static void force_swapin_readahead(struct vm_area_struct *vma, unsigned long start, unsigned long end) { struct mm_walk walk = { .mm = vma->vm_mm, .pmd_entry = swapin_walk_pmd_entry, .private = vma, }; walk_page_range(start, end, &walk); lru_add_drain(); /* Push any new pages onto the LRU now */ } static void force_shm_swapin_readahead(struct vm_area_struct *vma, unsigned long start, unsigned long end, struct address_space *mapping) { pgoff_t index; struct page *page; swp_entry_t swap; for (; start < end; start += PAGE_SIZE) { index = ((start - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff; |
55231e5c8 mm: madvise: fix ... |
247 |
page = find_get_entry(mapping, index); |
1998cc048 mm: make madvise(... |
248 249 |
if (!radix_tree_exceptional_entry(page)) { if (page) |
09cbfeaf1 mm, fs: get rid o... |
250 |
put_page(page); |
1998cc048 mm: make madvise(... |
251 252 253 254 |
continue; } swap = radix_to_swp_entry(page); page = read_swap_cache_async(swap, GFP_HIGHUSER_MOVABLE, |
23955622f swap: add block i... |
255 |
NULL, 0, false); |
1998cc048 mm: make madvise(... |
256 |
if (page) |
09cbfeaf1 mm, fs: get rid o... |
257 |
put_page(page); |
1998cc048 mm: make madvise(... |
258 259 260 261 262 |
} lru_add_drain(); /* Push any new pages onto the LRU now */ } #endif /* CONFIG_SWAP */ |
1da177e4c Linux-2.6.12-rc2 |
263 264 265 |
/* * Schedule all required I/O operations. Do not wait for completion. */ |
ec9bed9d3 mm/madvise.c: fix... |
266 267 |
static long madvise_willneed(struct vm_area_struct *vma, struct vm_area_struct **prev, |
1da177e4c Linux-2.6.12-rc2 |
268 269 270 |
unsigned long start, unsigned long end) { struct file *file = vma->vm_file; |
8a0bb9eba mm/madvise.c: fix... |
271 |
*prev = vma; |
1998cc048 mm: make madvise(... |
272 |
#ifdef CONFIG_SWAP |
97b713ba3 fs: kill BDI_CAP_... |
273 |
if (!file) { |
97b713ba3 fs: kill BDI_CAP_... |
274 |
force_swapin_readahead(vma, start, end); |
1998cc048 mm: make madvise(... |
275 276 |
return 0; } |
1998cc048 mm: make madvise(... |
277 |
|
97b713ba3 fs: kill BDI_CAP_... |
278 |
if (shmem_mapping(file->f_mapping)) { |
97b713ba3 fs: kill BDI_CAP_... |
279 280 281 282 283 |
force_shm_swapin_readahead(vma, start, end, file->f_mapping); return 0; } #else |
1bef40032 [PATCH] madvise: ... |
284 285 |
if (!file) return -EBADF; |
97b713ba3 fs: kill BDI_CAP_... |
286 |
#endif |
1bef40032 [PATCH] madvise: ... |
287 |
|
e748dcd09 vfs: remove get_x... |
288 |
if (IS_DAX(file_inode(file))) { |
fe77ba6f4 [PATCH] xip: madv... |
289 290 291 |
/* no bad return value, but ignore advice */ return 0; } |
1da177e4c Linux-2.6.12-rc2 |
292 293 294 295 |
start = ((start - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff; if (end > vma->vm_end) end = vma->vm_end; end = ((end - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff; |
f7e839dd3 readahead: move m... |
296 |
force_page_cache_readahead(file->f_mapping, file, start, end - start); |
1da177e4c Linux-2.6.12-rc2 |
297 298 |
return 0; } |
854e9ed09 mm: support madvi... |
299 300 301 302 303 304 305 306 307 308 |
static int madvise_free_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, struct mm_walk *walk) { struct mmu_gather *tlb = walk->private; struct mm_struct *mm = tlb->mm; struct vm_area_struct *vma = walk->vma; spinlock_t *ptl; pte_t *orig_pte, *pte, ptent; struct page *page; |
64b42bc1c mm/madvise.c: fre... |
309 |
int nr_swap = 0; |
b8d3c4c30 mm/huge_memory.c:... |
310 311 312 313 314 315 |
unsigned long next; next = pmd_addr_end(addr, end); if (pmd_trans_huge(*pmd)) if (madvise_free_huge_pmd(tlb, vma, pmd, addr, next)) goto next; |
854e9ed09 mm: support madvi... |
316 |
|
854e9ed09 mm: support madvi... |
317 318 |
if (pmd_trans_unstable(pmd)) return 0; |
07e326610 mm: add tlb_remov... |
319 |
tlb_remove_check_page_size_change(tlb, PAGE_SIZE); |
854e9ed09 mm: support madvi... |
320 |
orig_pte = pte = pte_offset_map_lock(mm, pmd, addr, &ptl); |
3ea277194 mm, mprotect: flu... |
321 |
flush_tlb_batched_pending(mm); |
854e9ed09 mm: support madvi... |
322 323 324 |
arch_enter_lazy_mmu_mode(); for (; addr != end; pte++, addr += PAGE_SIZE) { ptent = *pte; |
64b42bc1c mm/madvise.c: fre... |
325 |
if (pte_none(ptent)) |
854e9ed09 mm: support madvi... |
326 |
continue; |
64b42bc1c mm/madvise.c: fre... |
327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 |
/* * If the pte has swp_entry, just clear page table to * prevent swap-in which is more expensive rather than * (page allocation + zeroing). */ if (!pte_present(ptent)) { swp_entry_t entry; entry = pte_to_swp_entry(ptent); if (non_swap_entry(entry)) continue; nr_swap--; free_swap_and_cache(entry); pte_clear_not_present_full(mm, addr, pte, tlb->fullmm); continue; } |
854e9ed09 mm: support madvi... |
343 |
|
df6ad6983 mm/device-public-... |
344 |
page = _vm_normal_page(vma, addr, ptent, true); |
854e9ed09 mm: support madvi... |
345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 |
if (!page) continue; /* * If pmd isn't transhuge but the page is THP and * is owned by only this process, split it and * deactivate all pages. */ if (PageTransCompound(page)) { if (page_mapcount(page) != 1) goto out; get_page(page); if (!trylock_page(page)) { put_page(page); goto out; } pte_unmap_unlock(orig_pte, ptl); if (split_huge_page(page)) { unlock_page(page); put_page(page); pte_offset_map_lock(mm, pmd, addr, &ptl); goto out; } |
854e9ed09 mm: support madvi... |
368 |
unlock_page(page); |
263630e8d mm/madvise.c: fix... |
369 |
put_page(page); |
854e9ed09 mm: support madvi... |
370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 |
pte = pte_offset_map_lock(mm, pmd, addr, &ptl); pte--; addr -= PAGE_SIZE; continue; } VM_BUG_ON_PAGE(PageTransCompound(page), page); if (PageSwapCache(page) || PageDirty(page)) { if (!trylock_page(page)) continue; /* * If page is shared with others, we couldn't clear * PG_dirty of the page. */ if (page_mapcount(page) != 1) { unlock_page(page); continue; } if (PageSwapCache(page) && !try_to_free_swap(page)) { unlock_page(page); continue; } ClearPageDirty(page); unlock_page(page); } if (pte_young(ptent) || pte_dirty(ptent)) { /* * Some of architecture(ex, PPC) don't update TLB * with set_pte_at and tlb_remove_tlb_entry so for * the portability, remap the pte with old|clean * after pte clearing. */ ptent = ptep_get_and_clear_full(mm, addr, pte, tlb->fullmm); ptent = pte_mkold(ptent); ptent = pte_mkclean(ptent); set_pte_at(mm, addr, pte, ptent); tlb_remove_tlb_entry(tlb, pte, addr); } |
802a3a92a mm: reclaim MADV_... |
414 |
mark_page_lazyfree(page); |
854e9ed09 mm: support madvi... |
415 416 |
} out: |
64b42bc1c mm/madvise.c: fre... |
417 418 419 420 421 422 |
if (nr_swap) { if (current->mm == mm) sync_mm_rss(mm); add_mm_counter(mm, MM_SWAPENTS, nr_swap); } |
854e9ed09 mm: support madvi... |
423 424 425 |
arch_leave_lazy_mmu_mode(); pte_unmap_unlock(orig_pte, ptl); cond_resched(); |
b8d3c4c30 mm/huge_memory.c:... |
426 |
next: |
854e9ed09 mm: support madvi... |
427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 |
return 0; } static void madvise_free_page_range(struct mmu_gather *tlb, struct vm_area_struct *vma, unsigned long addr, unsigned long end) { struct mm_walk free_walk = { .pmd_entry = madvise_free_pte_range, .mm = vma->vm_mm, .private = tlb, }; tlb_start_vma(tlb, vma); walk_page_range(addr, end, &free_walk); tlb_end_vma(tlb, vma); } static int madvise_free_single_vma(struct vm_area_struct *vma, unsigned long start_addr, unsigned long end_addr) { unsigned long start, end; struct mm_struct *mm = vma->vm_mm; struct mmu_gather tlb; |
854e9ed09 mm: support madvi... |
451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 |
/* MADV_FREE works for only anon vma at the moment */ if (!vma_is_anonymous(vma)) return -EINVAL; start = max(vma->vm_start, start_addr); if (start >= vma->vm_end) return -EINVAL; end = min(vma->vm_end, end_addr); if (end <= vma->vm_start) return -EINVAL; lru_add_drain(); tlb_gather_mmu(&tlb, mm, start, end); update_hiwater_rss(mm); mmu_notifier_invalidate_range_start(mm, start, end); madvise_free_page_range(&tlb, vma, start, end); mmu_notifier_invalidate_range_end(mm, start, end); tlb_finish_mmu(&tlb, start, end); return 0; } |
1da177e4c Linux-2.6.12-rc2 |
473 474 475 476 |
/* * Application no longer needs these pages. If the pages are dirty, * it's OK to just throw them away. The app will be more careful about * data it wants to keep. Be sure to free swap resources too. The |
7e6cbea39 madvise: update f... |
477 |
* zap_page_range call sets things up for shrink_active_list to actually free |
1da177e4c Linux-2.6.12-rc2 |
478 479 |
* these pages later if no one else has touched them in the meantime, * although we could add these pages to a global reuse list for |
7e6cbea39 madvise: update f... |
480 |
* shrink_active_list to pick up before reclaiming other pages. |
1da177e4c Linux-2.6.12-rc2 |
481 482 483 484 485 486 487 488 489 490 491 |
* * NB: This interface discards data rather than pushes it out to swap, * as some implementations do. This has performance implications for * applications like large transactional databases which want to discard * pages in anonymous maps after committing to backing store the data * that was kept in them. There is no reason to write this data out to * the swap area if the application is discarding it. * * An interface that causes the system to free clean pages and flush * dirty pages is already available as msync(MS_INVALIDATE). */ |
230ca982b userfaultfd: non-... |
492 493 494 495 496 497 498 499 500 501 502 |
static long madvise_dontneed_single_vma(struct vm_area_struct *vma, unsigned long start, unsigned long end) { zap_page_range(vma, start, end - start); return 0; } static long madvise_dontneed_free(struct vm_area_struct *vma, struct vm_area_struct **prev, unsigned long start, unsigned long end, int behavior) |
1da177e4c Linux-2.6.12-rc2 |
503 |
{ |
05b743847 [PATCH] madvise: ... |
504 |
*prev = vma; |
235190738 oom-reaper: use m... |
505 |
if (!can_madv_dontneed_vma(vma)) |
1da177e4c Linux-2.6.12-rc2 |
506 |
return -EINVAL; |
70ccb92fd userfaultfd: non-... |
507 508 509 510 511 512 513 514 515 516 517 518 519 520 |
if (!userfaultfd_remove(vma, start, end)) { *prev = NULL; /* mmap_sem has been dropped, prev is stale */ down_read(¤t->mm->mmap_sem); vma = find_vma(current->mm, start); if (!vma) return -ENOMEM; if (start < vma->vm_start) { /* * This "vma" under revalidation is the one * with the lowest vma->vm_start where start * is also < vma->vm_end. If start < * vma->vm_start it means an hole materialized * in the user address space within the |
230ca982b userfaultfd: non-... |
521 522 |
* virtual range passed to MADV_DONTNEED * or MADV_FREE. |
70ccb92fd userfaultfd: non-... |
523 524 525 526 527 528 529 530 531 532 |
*/ return -ENOMEM; } if (!can_madv_dontneed_vma(vma)) return -EINVAL; if (end > vma->vm_end) { /* * Don't fail if end > vma->vm_end. If the old * vma was splitted while the mmap_sem was * released the effect of the concurrent |
230ca982b userfaultfd: non-... |
533 |
* operation may not cause madvise() to |
70ccb92fd userfaultfd: non-... |
534 535 536 537 538 539 540 541 542 543 544 |
* have an undefined result. There may be an * adjacent next vma that we'll walk * next. userfaultfd_remove() will generate an * UFFD_EVENT_REMOVE repetition on the * end-vma->vm_end range, but the manager can * handle a repetition fine. */ end = vma->vm_end; } VM_WARN_ON(start >= end); } |
230ca982b userfaultfd: non-... |
545 546 547 548 549 550 551 |
if (behavior == MADV_DONTNEED) return madvise_dontneed_single_vma(vma, start, end); else if (behavior == MADV_FREE) return madvise_free_single_vma(vma, start, end); else return -EINVAL; |
1da177e4c Linux-2.6.12-rc2 |
552 |
} |
f6b3ec238 [PATCH] madvise(M... |
553 554 555 |
/* * Application wants to free up the pages and associated backing store. * This is effectively punching a hole into the middle of a file. |
f6b3ec238 [PATCH] madvise(M... |
556 557 |
*/ static long madvise_remove(struct vm_area_struct *vma, |
00e9fa2d6 [PATCH] mm: fix m... |
558 |
struct vm_area_struct **prev, |
f6b3ec238 [PATCH] madvise(M... |
559 560 |
unsigned long start, unsigned long end) { |
3f31d0757 mm/fs: route MADV... |
561 |
loff_t offset; |
90ed52ebe [PATCH] holepunch... |
562 |
int error; |
9ab4233dd mm: Hold a file r... |
563 |
struct file *f; |
f6b3ec238 [PATCH] madvise(M... |
564 |
|
90ed52ebe [PATCH] holepunch... |
565 |
*prev = NULL; /* tell sys_madvise we drop mmap_sem */ |
00e9fa2d6 [PATCH] mm: fix m... |
566 |
|
72079ba0d mm: madvise allow... |
567 |
if (vma->vm_flags & VM_LOCKED) |
f6b3ec238 [PATCH] madvise(M... |
568 |
return -EINVAL; |
9ab4233dd mm: Hold a file r... |
569 570 571 |
f = vma->vm_file; if (!f || !f->f_mapping || !f->f_mapping->host) { |
f6b3ec238 [PATCH] madvise(M... |
572 573 |
return -EINVAL; } |
69cf0fac6 [PATCH] Fix MADV_... |
574 575 |
if ((vma->vm_flags & (VM_SHARED|VM_WRITE)) != (VM_SHARED|VM_WRITE)) return -EACCES; |
f6b3ec238 [PATCH] madvise(M... |
576 577 |
offset = (loff_t)(start - vma->vm_start) + ((loff_t)vma->vm_pgoff << PAGE_SHIFT); |
90ed52ebe [PATCH] holepunch... |
578 |
|
9ab4233dd mm: Hold a file r... |
579 580 581 582 583 584 585 |
/* * Filesystem's fallocate may need to take i_mutex. We need to * explicitly grab a reference because the vma (and hence the * vma's reference to the file) can go away as soon as we drop * mmap_sem. */ get_file(f); |
70ccb92fd userfaultfd: non-... |
586 587 588 589 |
if (userfaultfd_remove(vma, start, end)) { /* mmap_sem was not released by userfaultfd_remove() */ up_read(¤t->mm->mmap_sem); } |
72c72bdf7 VFS: Rename do_fa... |
590 |
error = vfs_fallocate(f, |
3f31d0757 mm/fs: route MADV... |
591 592 |
FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE, offset, end - start); |
9ab4233dd mm: Hold a file r... |
593 |
fput(f); |
0a27a14a6 mm: madvise avoid... |
594 |
down_read(¤t->mm->mmap_sem); |
90ed52ebe [PATCH] holepunch... |
595 |
return error; |
f6b3ec238 [PATCH] madvise(M... |
596 |
} |
9893e49d6 HWPOISON: Add mad... |
597 598 599 600 |
#ifdef CONFIG_MEMORY_FAILURE /* * Error injection support for memory error handling. */ |
97167a768 mm/madvise.c: cle... |
601 602 |
static int madvise_inject_error(int behavior, unsigned long start, unsigned long end) |
9893e49d6 HWPOISON: Add mad... |
603 |
{ |
97167a768 mm/madvise.c: cle... |
604 |
struct page *page; |
c461ad6a6 mm, madvise: ensu... |
605 |
struct zone *zone; |
19bfbe22f mm, hugetlb, soft... |
606 |
unsigned int order; |
97167a768 mm/madvise.c: cle... |
607 |
|
9893e49d6 HWPOISON: Add mad... |
608 609 |
if (!capable(CAP_SYS_ADMIN)) return -EPERM; |
97167a768 mm/madvise.c: cle... |
610 |
|
19bfbe22f mm, hugetlb, soft... |
611 612 |
for (; start < end; start += PAGE_SIZE << order) { |
325c4ef5c mm/madvise.c:madv... |
613 |
int ret; |
97167a768 mm/madvise.c: cle... |
614 |
ret = get_user_pages_fast(start, 1, 0, &page); |
9893e49d6 HWPOISON: Add mad... |
615 616 |
if (ret != 1) return ret; |
325c4ef5c mm/madvise.c:madv... |
617 |
|
19bfbe22f mm, hugetlb, soft... |
618 619 620 621 622 623 |
/* * When soft offlining hugepages, after migrating the page * we dissolve it, therefore in the second loop "page" will * no longer be a compound page, and order will be 0. */ order = compound_order(compound_head(page)); |
97167a768 mm/madvise.c: cle... |
624 625 |
if (PageHWPoison(page)) { put_page(page); |
29b4eedee mm/hwpoison.c: fi... |
626 627 |
continue; } |
97167a768 mm/madvise.c: cle... |
628 629 630 631 632 633 634 |
if (behavior == MADV_SOFT_OFFLINE) { pr_info("Soft offlining pfn %#lx at process virtual address %#lx ", page_to_pfn(page), start); ret = soft_offline_page(page, MF_COUNT_INCREASED); |
afcf938ee HWPOISON: Add a m... |
635 |
if (ret) |
8302423b8 mm/madvise.c: fix... |
636 |
return ret; |
afcf938ee HWPOISON: Add a m... |
637 638 |
continue; } |
97167a768 mm/madvise.c: cle... |
639 640 641 642 643 |
pr_info("Injecting memory failure for pfn %#lx at process virtual address %#lx ", page_to_pfn(page), start); ret = memory_failure(page_to_pfn(page), 0, MF_COUNT_INCREASED); |
23a003bfd mm/madvise: pass ... |
644 645 |
if (ret) return ret; |
9893e49d6 HWPOISON: Add mad... |
646 |
} |
c461ad6a6 mm, madvise: ensu... |
647 648 649 650 |
/* Ensure that all poisoned pages are removed from per-cpu lists */ for_each_populated_zone(zone) drain_all_pages(zone); |
325c4ef5c mm/madvise.c:madv... |
651 |
return 0; |
9893e49d6 HWPOISON: Add mad... |
652 653 |
} #endif |
165cd4023 [PATCH] madvise()... |
654 655 656 |
static long madvise_vma(struct vm_area_struct *vma, struct vm_area_struct **prev, unsigned long start, unsigned long end, int behavior) |
1da177e4c Linux-2.6.12-rc2 |
657 |
{ |
1da177e4c Linux-2.6.12-rc2 |
658 |
switch (behavior) { |
f6b3ec238 [PATCH] madvise(M... |
659 |
case MADV_REMOVE: |
3866ea90d ksm: first tidy u... |
660 |
return madvise_remove(vma, prev, start, end); |
1da177e4c Linux-2.6.12-rc2 |
661 |
case MADV_WILLNEED: |
3866ea90d ksm: first tidy u... |
662 |
return madvise_willneed(vma, prev, start, end); |
854e9ed09 mm: support madvi... |
663 |
case MADV_FREE: |
1da177e4c Linux-2.6.12-rc2 |
664 |
case MADV_DONTNEED: |
230ca982b userfaultfd: non-... |
665 |
return madvise_dontneed_free(vma, prev, start, end, behavior); |
1da177e4c Linux-2.6.12-rc2 |
666 |
default: |
3866ea90d ksm: first tidy u... |
667 |
return madvise_behavior(vma, prev, start, end, behavior); |
1da177e4c Linux-2.6.12-rc2 |
668 |
} |
1da177e4c Linux-2.6.12-rc2 |
669 |
} |
1ecef9ed0 mm/madvise.c: mak... |
670 |
static bool |
75927af8b mm: madvise(): co... |
671 672 673 674 675 676 677 678 679 680 681 |
madvise_behavior_valid(int behavior) { switch (behavior) { case MADV_DOFORK: case MADV_DONTFORK: case MADV_NORMAL: case MADV_SEQUENTIAL: case MADV_RANDOM: case MADV_REMOVE: case MADV_WILLNEED: case MADV_DONTNEED: |
854e9ed09 mm: support madvi... |
682 |
case MADV_FREE: |
f8af4da3b ksm: the mm inter... |
683 684 685 686 |
#ifdef CONFIG_KSM case MADV_MERGEABLE: case MADV_UNMERGEABLE: #endif |
0af4e98b6 thp: madvise(MADV... |
687 688 |
#ifdef CONFIG_TRANSPARENT_HUGEPAGE case MADV_HUGEPAGE: |
a664b2d85 thp: madvise(MADV... |
689 |
case MADV_NOHUGEPAGE: |
0af4e98b6 thp: madvise(MADV... |
690 |
#endif |
accb61fe7 coredump: add VM_... |
691 692 |
case MADV_DONTDUMP: case MADV_DODUMP: |
d2cd9ede6 mm,fork: introduc... |
693 694 |
case MADV_WIPEONFORK: case MADV_KEEPONFORK: |
5e451be75 mm/madvise: move ... |
695 696 697 698 |
#ifdef CONFIG_MEMORY_FAILURE case MADV_SOFT_OFFLINE: case MADV_HWPOISON: #endif |
1ecef9ed0 mm/madvise.c: mak... |
699 |
return true; |
75927af8b mm: madvise(): co... |
700 701 |
default: |
1ecef9ed0 mm/madvise.c: mak... |
702 |
return false; |
75927af8b mm: madvise(): co... |
703 704 |
} } |
3866ea90d ksm: first tidy u... |
705 |
|
1da177e4c Linux-2.6.12-rc2 |
706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 |
/* * The madvise(2) system call. * * Applications can use madvise() to advise the kernel how it should * handle paging I/O in this VM area. The idea is to help the kernel * use appropriate read-ahead and caching techniques. The information * provided is advisory only, and can be safely disregarded by the * kernel without affecting the correct operation of the application. * * behavior values: * MADV_NORMAL - the default behavior is to read clusters. This * results in some read-ahead and read-behind. * MADV_RANDOM - the system should read the minimum amount of data * on any access, since it is unlikely that the appli- * cation will need more than what it asks for. * MADV_SEQUENTIAL - pages in the given range will probably be accessed * once, so they can be aggressively read ahead, and * can be freed soon after they are accessed. * MADV_WILLNEED - the application is notifying the system to read * some pages ahead. * MADV_DONTNEED - the application is finished with the given range, * so the kernel can free resources associated with it. |
d7206a70a mm/madvise: updat... |
728 729 |
* MADV_FREE - the application marks pages in the given range as lazy free, * where actual purges are postponed until memory pressure happens. |
f6b3ec238 [PATCH] madvise(M... |
730 731 |
* MADV_REMOVE - the application wants to free up the given range of * pages and associated backing store. |
3866ea90d ksm: first tidy u... |
732 733 734 |
* MADV_DONTFORK - omit this area from child's address space when forking: * typically, to avoid COWing pages pinned by get_user_pages(). * MADV_DOFORK - cancel MADV_DONTFORK: no longer omit this area when forking. |
c02c30093 mm/madvise.c: add... |
735 736 737 |
* MADV_WIPEONFORK - present the child process with zero-filled memory in this * range after a fork. * MADV_KEEPONFORK - undo the effect of MADV_WIPEONFORK |
d7206a70a mm/madvise: updat... |
738 739 740 |
* MADV_HWPOISON - trigger memory error handler as if the given memory range * were corrupted by unrecoverable hardware memory failure. * MADV_SOFT_OFFLINE - try to soft-offline the given range of memory. |
f8af4da3b ksm: the mm inter... |
741 742 743 |
* MADV_MERGEABLE - the application recommends that KSM try to merge pages in * this area with pages of identical content from other such areas. * MADV_UNMERGEABLE- cancel MADV_MERGEABLE: no longer merge pages with others. |
d7206a70a mm/madvise: updat... |
744 745 746 747 748 749 750 751 752 |
* MADV_HUGEPAGE - the application wants to back the given range by transparent * huge pages in the future. Existing pages might be coalesced and * new pages might be allocated as THP. * MADV_NOHUGEPAGE - mark the given range as not worth being backed by * transparent huge pages so the existing pages will not be * coalesced into THP and new pages will not be allocated as THP. * MADV_DONTDUMP - the application wants to prevent pages in the given range * from being included in its core dump. * MADV_DODUMP - cancel MADV_DONTDUMP: no longer exclude from core dump. |
1da177e4c Linux-2.6.12-rc2 |
753 754 755 756 757 |
* * return values: * zero - success * -EINVAL - start + len < 0, start is not page-aligned, * "behavior" is not a valid value, or application |
c02c30093 mm/madvise.c: add... |
758 759 760 |
* is attempting to release locked or shared pages, * or the specified address range includes file, Huge TLB, * MAP_SHARED or VMPFNMAP range. |
1da177e4c Linux-2.6.12-rc2 |
761 762 763 764 765 766 |
* -ENOMEM - addresses in the specified range are not currently * mapped, or are outside the AS of the process. * -EIO - an I/O error occurred while paging in data. * -EBADF - map exists, but area maps something that isn't a file. * -EAGAIN - a kernel resource was temporarily unavailable. */ |
3480b2574 [CVE-2009-0029] S... |
767 |
SYSCALL_DEFINE3(madvise, unsigned long, start, size_t, len_in, int, behavior) |
1da177e4c Linux-2.6.12-rc2 |
768 |
{ |
05b743847 [PATCH] madvise: ... |
769 |
unsigned long end, tmp; |
ec9bed9d3 mm/madvise.c: fix... |
770 |
struct vm_area_struct *vma, *prev; |
1da177e4c Linux-2.6.12-rc2 |
771 772 |
int unmapped_error = 0; int error = -EINVAL; |
f79777932 speed up madvise_... |
773 |
int write; |
1da177e4c Linux-2.6.12-rc2 |
774 |
size_t len; |
1998cc048 mm: make madvise(... |
775 |
struct blk_plug plug; |
1da177e4c Linux-2.6.12-rc2 |
776 |
|
75927af8b mm: madvise(): co... |
777 778 |
if (!madvise_behavior_valid(behavior)) return error; |
1da177e4c Linux-2.6.12-rc2 |
779 |
if (start & ~PAGE_MASK) |
84d96d897 mm: madvise: comp... |
780 |
return error; |
1da177e4c Linux-2.6.12-rc2 |
781 782 783 784 |
len = (len_in + ~PAGE_MASK) & PAGE_MASK; /* Check to see whether len was rounded up from small -ve to zero */ if (len_in && !len) |
84d96d897 mm: madvise: comp... |
785 |
return error; |
1da177e4c Linux-2.6.12-rc2 |
786 787 788 |
end = start + len; if (end < start) |
84d96d897 mm: madvise: comp... |
789 |
return error; |
1da177e4c Linux-2.6.12-rc2 |
790 791 792 |
error = 0; if (end == start) |
84d96d897 mm: madvise: comp... |
793 |
return error; |
5e451be75 mm/madvise: move ... |
794 795 796 797 |
#ifdef CONFIG_MEMORY_FAILURE if (behavior == MADV_HWPOISON || behavior == MADV_SOFT_OFFLINE) return madvise_inject_error(behavior, start, start + len_in); #endif |
84d96d897 mm: madvise: comp... |
798 |
write = madvise_need_mmap_write(behavior); |
dc0ef0df7 mm: make mmap_sem... |
799 800 801 802 |
if (write) { if (down_write_killable(¤t->mm->mmap_sem)) return -EINTR; } else { |
84d96d897 mm: madvise: comp... |
803 |
down_read(¤t->mm->mmap_sem); |
dc0ef0df7 mm: make mmap_sem... |
804 |
} |
1da177e4c Linux-2.6.12-rc2 |
805 806 807 808 |
/* * If the interval [start,end) covers some unmapped address * ranges, just ignore them, but return -ENOMEM at the end. |
05b743847 [PATCH] madvise: ... |
809 |
* - different from the way of handling in mlock etc. |
1da177e4c Linux-2.6.12-rc2 |
810 |
*/ |
05b743847 [PATCH] madvise: ... |
811 |
vma = find_vma_prev(current->mm, start, &prev); |
836d5ffd3 [PATCH] mm: fix m... |
812 813 |
if (vma && start > vma->vm_start) prev = vma; |
1998cc048 mm: make madvise(... |
814 |
blk_start_plug(&plug); |
1da177e4c Linux-2.6.12-rc2 |
815 816 817 818 |
for (;;) { /* Still start < end. */ error = -ENOMEM; if (!vma) |
84d96d897 mm: madvise: comp... |
819 |
goto out; |
1da177e4c Linux-2.6.12-rc2 |
820 |
|
05b743847 [PATCH] madvise: ... |
821 |
/* Here start < (end|vma->vm_end). */ |
1da177e4c Linux-2.6.12-rc2 |
822 823 824 |
if (start < vma->vm_start) { unmapped_error = -ENOMEM; start = vma->vm_start; |
05b743847 [PATCH] madvise: ... |
825 |
if (start >= end) |
84d96d897 mm: madvise: comp... |
826 |
goto out; |
1da177e4c Linux-2.6.12-rc2 |
827 |
} |
05b743847 [PATCH] madvise: ... |
828 829 830 831 |
/* Here vma->vm_start <= start < (end|vma->vm_end) */ tmp = vma->vm_end; if (end < tmp) tmp = end; |
1da177e4c Linux-2.6.12-rc2 |
832 |
|
05b743847 [PATCH] madvise: ... |
833 834 |
/* Here vma->vm_start <= start < tmp <= (end|vma->vm_end). */ error = madvise_vma(vma, &prev, start, tmp, behavior); |
1da177e4c Linux-2.6.12-rc2 |
835 |
if (error) |
84d96d897 mm: madvise: comp... |
836 |
goto out; |
05b743847 [PATCH] madvise: ... |
837 |
start = tmp; |
90ed52ebe [PATCH] holepunch... |
838 |
if (prev && start < prev->vm_end) |
05b743847 [PATCH] madvise: ... |
839 840 841 |
start = prev->vm_end; error = unmapped_error; if (start >= end) |
84d96d897 mm: madvise: comp... |
842 |
goto out; |
90ed52ebe [PATCH] holepunch... |
843 844 845 846 |
if (prev) vma = prev->vm_next; else /* madvise_remove dropped mmap_sem */ vma = find_vma(current->mm, start); |
1da177e4c Linux-2.6.12-rc2 |
847 |
} |
1da177e4c Linux-2.6.12-rc2 |
848 |
out: |
84d96d897 mm: madvise: comp... |
849 |
blk_finish_plug(&plug); |
f79777932 speed up madvise_... |
850 |
if (write) |
0a27a14a6 mm: madvise avoid... |
851 852 853 |
up_write(¤t->mm->mmap_sem); else up_read(¤t->mm->mmap_sem); |
1da177e4c Linux-2.6.12-rc2 |
854 855 |
return error; } |