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Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * Simple NUMA memory policy for the Linux kernel. | |
3 | * | |
4 | * Copyright 2003,2004 Andi Kleen, SuSE Labs. | |
8bccd85f | 5 | * (C) Copyright 2005 Christoph Lameter, Silicon Graphics, Inc. |
1da177e4 LT |
6 | * Subject to the GNU Public License, version 2. |
7 | * | |
8 | * NUMA policy allows the user to give hints in which node(s) memory should | |
9 | * be allocated. | |
10 | * | |
11 | * Support four policies per VMA and per process: | |
12 | * | |
13 | * The VMA policy has priority over the process policy for a page fault. | |
14 | * | |
15 | * interleave Allocate memory interleaved over a set of nodes, | |
16 | * with normal fallback if it fails. | |
17 | * For VMA based allocations this interleaves based on the | |
18 | * offset into the backing object or offset into the mapping | |
19 | * for anonymous memory. For process policy an process counter | |
20 | * is used. | |
8bccd85f | 21 | * |
1da177e4 LT |
22 | * bind Only allocate memory on a specific set of nodes, |
23 | * no fallback. | |
8bccd85f CL |
24 | * FIXME: memory is allocated starting with the first node |
25 | * to the last. It would be better if bind would truly restrict | |
26 | * the allocation to memory nodes instead | |
27 | * | |
1da177e4 LT |
28 | * preferred Try a specific node first before normal fallback. |
29 | * As a special case node -1 here means do the allocation | |
30 | * on the local CPU. This is normally identical to default, | |
31 | * but useful to set in a VMA when you have a non default | |
32 | * process policy. | |
8bccd85f | 33 | * |
1da177e4 LT |
34 | * default Allocate on the local node first, or when on a VMA |
35 | * use the process policy. This is what Linux always did | |
36 | * in a NUMA aware kernel and still does by, ahem, default. | |
37 | * | |
38 | * The process policy is applied for most non interrupt memory allocations | |
39 | * in that process' context. Interrupts ignore the policies and always | |
40 | * try to allocate on the local CPU. The VMA policy is only applied for memory | |
41 | * allocations for a VMA in the VM. | |
42 | * | |
43 | * Currently there are a few corner cases in swapping where the policy | |
44 | * is not applied, but the majority should be handled. When process policy | |
45 | * is used it is not remembered over swap outs/swap ins. | |
46 | * | |
47 | * Only the highest zone in the zone hierarchy gets policied. Allocations | |
48 | * requesting a lower zone just use default policy. This implies that | |
49 | * on systems with highmem kernel lowmem allocation don't get policied. | |
50 | * Same with GFP_DMA allocations. | |
51 | * | |
52 | * For shmfs/tmpfs/hugetlbfs shared memory the policy is shared between | |
53 | * all users and remembered even when nobody has memory mapped. | |
54 | */ | |
55 | ||
56 | /* Notebook: | |
57 | fix mmap readahead to honour policy and enable policy for any page cache | |
58 | object | |
59 | statistics for bigpages | |
60 | global policy for page cache? currently it uses process policy. Requires | |
61 | first item above. | |
62 | handle mremap for shared memory (currently ignored for the policy) | |
63 | grows down? | |
64 | make bind policy root only? It can trigger oom much faster and the | |
65 | kernel is not always grateful with that. | |
66 | could replace all the switch()es with a mempolicy_ops structure. | |
67 | */ | |
68 | ||
69 | #include <linux/mempolicy.h> | |
70 | #include <linux/mm.h> | |
71 | #include <linux/highmem.h> | |
72 | #include <linux/hugetlb.h> | |
73 | #include <linux/kernel.h> | |
74 | #include <linux/sched.h> | |
75 | #include <linux/mm.h> | |
76 | #include <linux/nodemask.h> | |
77 | #include <linux/cpuset.h> | |
78 | #include <linux/gfp.h> | |
79 | #include <linux/slab.h> | |
80 | #include <linux/string.h> | |
81 | #include <linux/module.h> | |
82 | #include <linux/interrupt.h> | |
83 | #include <linux/init.h> | |
84 | #include <linux/compat.h> | |
85 | #include <linux/mempolicy.h> | |
dc9aa5b9 CL |
86 | #include <linux/swap.h> |
87 | ||
1da177e4 LT |
88 | #include <asm/tlbflush.h> |
89 | #include <asm/uaccess.h> | |
90 | ||
dc9aa5b9 CL |
91 | /* Internal MPOL_MF_xxx flags */ |
92 | #define MPOL_MF_DISCONTIG_OK (MPOL_MF_INTERNAL << 0) /* Skip checks for continuous vmas */ | |
93 | ||
1da177e4 LT |
94 | static kmem_cache_t *policy_cache; |
95 | static kmem_cache_t *sn_cache; | |
96 | ||
97 | #define PDprintk(fmt...) | |
98 | ||
99 | /* Highest zone. An specific allocation for a zone below that is not | |
100 | policied. */ | |
4be38e35 | 101 | int policy_zone = ZONE_DMA; |
1da177e4 | 102 | |
d42c6997 | 103 | struct mempolicy default_policy = { |
1da177e4 LT |
104 | .refcnt = ATOMIC_INIT(1), /* never free it */ |
105 | .policy = MPOL_DEFAULT, | |
106 | }; | |
107 | ||
1da177e4 | 108 | /* Do sanity checking on a policy */ |
dfcd3c0d | 109 | static int mpol_check_policy(int mode, nodemask_t *nodes) |
1da177e4 | 110 | { |
dfcd3c0d | 111 | int empty = nodes_empty(*nodes); |
1da177e4 LT |
112 | |
113 | switch (mode) { | |
114 | case MPOL_DEFAULT: | |
115 | if (!empty) | |
116 | return -EINVAL; | |
117 | break; | |
118 | case MPOL_BIND: | |
119 | case MPOL_INTERLEAVE: | |
120 | /* Preferred will only use the first bit, but allow | |
121 | more for now. */ | |
122 | if (empty) | |
123 | return -EINVAL; | |
124 | break; | |
125 | } | |
dfcd3c0d | 126 | return nodes_subset(*nodes, node_online_map) ? 0 : -EINVAL; |
1da177e4 | 127 | } |
1da177e4 | 128 | /* Generate a custom zonelist for the BIND policy. */ |
dfcd3c0d | 129 | static struct zonelist *bind_zonelist(nodemask_t *nodes) |
1da177e4 LT |
130 | { |
131 | struct zonelist *zl; | |
132 | int num, max, nd; | |
133 | ||
dfcd3c0d | 134 | max = 1 + MAX_NR_ZONES * nodes_weight(*nodes); |
1da177e4 LT |
135 | zl = kmalloc(sizeof(void *) * max, GFP_KERNEL); |
136 | if (!zl) | |
137 | return NULL; | |
138 | num = 0; | |
4be38e35 CL |
139 | for_each_node_mask(nd, *nodes) |
140 | zl->zones[num++] = &NODE_DATA(nd)->node_zones[policy_zone]; | |
1da177e4 LT |
141 | zl->zones[num] = NULL; |
142 | return zl; | |
143 | } | |
144 | ||
145 | /* Create a new policy */ | |
dfcd3c0d | 146 | static struct mempolicy *mpol_new(int mode, nodemask_t *nodes) |
1da177e4 LT |
147 | { |
148 | struct mempolicy *policy; | |
149 | ||
dfcd3c0d | 150 | PDprintk("setting mode %d nodes[0] %lx\n", mode, nodes_addr(*nodes)[0]); |
1da177e4 LT |
151 | if (mode == MPOL_DEFAULT) |
152 | return NULL; | |
153 | policy = kmem_cache_alloc(policy_cache, GFP_KERNEL); | |
154 | if (!policy) | |
155 | return ERR_PTR(-ENOMEM); | |
156 | atomic_set(&policy->refcnt, 1); | |
157 | switch (mode) { | |
158 | case MPOL_INTERLEAVE: | |
dfcd3c0d | 159 | policy->v.nodes = *nodes; |
8f493d79 AK |
160 | if (nodes_weight(*nodes) == 0) { |
161 | kmem_cache_free(policy_cache, policy); | |
162 | return ERR_PTR(-EINVAL); | |
163 | } | |
1da177e4 LT |
164 | break; |
165 | case MPOL_PREFERRED: | |
dfcd3c0d | 166 | policy->v.preferred_node = first_node(*nodes); |
1da177e4 LT |
167 | if (policy->v.preferred_node >= MAX_NUMNODES) |
168 | policy->v.preferred_node = -1; | |
169 | break; | |
170 | case MPOL_BIND: | |
171 | policy->v.zonelist = bind_zonelist(nodes); | |
172 | if (policy->v.zonelist == NULL) { | |
173 | kmem_cache_free(policy_cache, policy); | |
174 | return ERR_PTR(-ENOMEM); | |
175 | } | |
176 | break; | |
177 | } | |
178 | policy->policy = mode; | |
179 | return policy; | |
180 | } | |
181 | ||
dc9aa5b9 CL |
182 | /* Check if we are the only process mapping the page in question */ |
183 | static inline int single_mm_mapping(struct mm_struct *mm, | |
184 | struct address_space *mapping) | |
185 | { | |
186 | struct vm_area_struct *vma; | |
187 | struct prio_tree_iter iter; | |
188 | int rc = 1; | |
189 | ||
190 | spin_lock(&mapping->i_mmap_lock); | |
191 | vma_prio_tree_foreach(vma, &iter, &mapping->i_mmap, 0, ULONG_MAX) | |
192 | if (mm != vma->vm_mm) { | |
193 | rc = 0; | |
194 | goto out; | |
195 | } | |
196 | list_for_each_entry(vma, &mapping->i_mmap_nonlinear, shared.vm_set.list) | |
197 | if (mm != vma->vm_mm) { | |
198 | rc = 0; | |
199 | goto out; | |
200 | } | |
201 | out: | |
202 | spin_unlock(&mapping->i_mmap_lock); | |
203 | return rc; | |
204 | } | |
205 | ||
206 | /* | |
207 | * Add a page to be migrated to the pagelist | |
208 | */ | |
209 | static void migrate_page_add(struct vm_area_struct *vma, | |
210 | struct page *page, struct list_head *pagelist, unsigned long flags) | |
211 | { | |
212 | /* | |
213 | * Avoid migrating a page that is shared by others and not writable. | |
214 | */ | |
215 | if ((flags & MPOL_MF_MOVE_ALL) || !page->mapping || PageAnon(page) || | |
216 | mapping_writably_mapped(page->mapping) || | |
217 | single_mm_mapping(vma->vm_mm, page->mapping)) { | |
218 | int rc = isolate_lru_page(page); | |
219 | ||
220 | if (rc == 1) | |
221 | list_add(&page->lru, pagelist); | |
222 | /* | |
223 | * If the isolate attempt was not successful then we just | |
224 | * encountered an unswappable page. Something must be wrong. | |
225 | */ | |
226 | WARN_ON(rc == 0); | |
227 | } | |
228 | } | |
229 | ||
1da177e4 | 230 | /* Ensure all existing pages follow the policy. */ |
b5810039 | 231 | static int check_pte_range(struct vm_area_struct *vma, pmd_t *pmd, |
dc9aa5b9 CL |
232 | unsigned long addr, unsigned long end, |
233 | const nodemask_t *nodes, unsigned long flags, | |
234 | struct list_head *pagelist) | |
1da177e4 | 235 | { |
91612e0d HD |
236 | pte_t *orig_pte; |
237 | pte_t *pte; | |
705e87c0 | 238 | spinlock_t *ptl; |
941150a3 | 239 | |
705e87c0 | 240 | orig_pte = pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); |
91612e0d | 241 | do { |
6aab341e | 242 | struct page *page; |
91612e0d HD |
243 | unsigned int nid; |
244 | ||
245 | if (!pte_present(*pte)) | |
1da177e4 | 246 | continue; |
6aab341e LT |
247 | page = vm_normal_page(vma, addr, *pte); |
248 | if (!page) | |
1da177e4 | 249 | continue; |
6aab341e | 250 | nid = page_to_nid(page); |
dc9aa5b9 CL |
251 | if (!node_isset(nid, *nodes)) { |
252 | if (pagelist) | |
253 | migrate_page_add(vma, page, pagelist, flags); | |
254 | else | |
255 | break; | |
256 | } | |
91612e0d | 257 | } while (pte++, addr += PAGE_SIZE, addr != end); |
705e87c0 | 258 | pte_unmap_unlock(orig_pte, ptl); |
91612e0d HD |
259 | return addr != end; |
260 | } | |
261 | ||
b5810039 | 262 | static inline int check_pmd_range(struct vm_area_struct *vma, pud_t *pud, |
dc9aa5b9 CL |
263 | unsigned long addr, unsigned long end, |
264 | const nodemask_t *nodes, unsigned long flags, | |
265 | struct list_head *pagelist) | |
91612e0d HD |
266 | { |
267 | pmd_t *pmd; | |
268 | unsigned long next; | |
269 | ||
270 | pmd = pmd_offset(pud, addr); | |
271 | do { | |
272 | next = pmd_addr_end(addr, end); | |
273 | if (pmd_none_or_clear_bad(pmd)) | |
274 | continue; | |
dc9aa5b9 CL |
275 | if (check_pte_range(vma, pmd, addr, next, nodes, |
276 | flags, pagelist)) | |
91612e0d HD |
277 | return -EIO; |
278 | } while (pmd++, addr = next, addr != end); | |
279 | return 0; | |
280 | } | |
281 | ||
b5810039 | 282 | static inline int check_pud_range(struct vm_area_struct *vma, pgd_t *pgd, |
dc9aa5b9 CL |
283 | unsigned long addr, unsigned long end, |
284 | const nodemask_t *nodes, unsigned long flags, | |
285 | struct list_head *pagelist) | |
91612e0d HD |
286 | { |
287 | pud_t *pud; | |
288 | unsigned long next; | |
289 | ||
290 | pud = pud_offset(pgd, addr); | |
291 | do { | |
292 | next = pud_addr_end(addr, end); | |
293 | if (pud_none_or_clear_bad(pud)) | |
294 | continue; | |
dc9aa5b9 CL |
295 | if (check_pmd_range(vma, pud, addr, next, nodes, |
296 | flags, pagelist)) | |
91612e0d HD |
297 | return -EIO; |
298 | } while (pud++, addr = next, addr != end); | |
299 | return 0; | |
300 | } | |
301 | ||
b5810039 | 302 | static inline int check_pgd_range(struct vm_area_struct *vma, |
dc9aa5b9 CL |
303 | unsigned long addr, unsigned long end, |
304 | const nodemask_t *nodes, unsigned long flags, | |
305 | struct list_head *pagelist) | |
91612e0d HD |
306 | { |
307 | pgd_t *pgd; | |
308 | unsigned long next; | |
309 | ||
b5810039 | 310 | pgd = pgd_offset(vma->vm_mm, addr); |
91612e0d HD |
311 | do { |
312 | next = pgd_addr_end(addr, end); | |
313 | if (pgd_none_or_clear_bad(pgd)) | |
314 | continue; | |
dc9aa5b9 CL |
315 | if (check_pud_range(vma, pgd, addr, next, nodes, |
316 | flags, pagelist)) | |
91612e0d HD |
317 | return -EIO; |
318 | } while (pgd++, addr = next, addr != end); | |
319 | return 0; | |
1da177e4 LT |
320 | } |
321 | ||
dc9aa5b9 CL |
322 | /* Check if a vma is migratable */ |
323 | static inline int vma_migratable(struct vm_area_struct *vma) | |
324 | { | |
325 | if (vma->vm_flags & ( | |
326 | VM_LOCKED|VM_IO|VM_HUGETLB|VM_PFNMAP)) | |
327 | return 0; | |
328 | return 1; | |
329 | } | |
330 | ||
331 | /* | |
332 | * Check if all pages in a range are on a set of nodes. | |
333 | * If pagelist != NULL then isolate pages from the LRU and | |
334 | * put them on the pagelist. | |
335 | */ | |
1da177e4 LT |
336 | static struct vm_area_struct * |
337 | check_range(struct mm_struct *mm, unsigned long start, unsigned long end, | |
dc9aa5b9 CL |
338 | const nodemask_t *nodes, unsigned long flags, |
339 | struct list_head *pagelist) | |
1da177e4 LT |
340 | { |
341 | int err; | |
342 | struct vm_area_struct *first, *vma, *prev; | |
343 | ||
344 | first = find_vma(mm, start); | |
345 | if (!first) | |
346 | return ERR_PTR(-EFAULT); | |
347 | prev = NULL; | |
348 | for (vma = first; vma && vma->vm_start < end; vma = vma->vm_next) { | |
dc9aa5b9 CL |
349 | if (!(flags & MPOL_MF_DISCONTIG_OK)) { |
350 | if (!vma->vm_next && vma->vm_end < end) | |
351 | return ERR_PTR(-EFAULT); | |
352 | if (prev && prev->vm_end < vma->vm_start) | |
353 | return ERR_PTR(-EFAULT); | |
354 | } | |
355 | if (!is_vm_hugetlb_page(vma) && | |
356 | ((flags & MPOL_MF_STRICT) || | |
357 | ((flags & (MPOL_MF_MOVE | MPOL_MF_MOVE_ALL)) && | |
358 | vma_migratable(vma)))) { | |
5b952b3c | 359 | unsigned long endvma = vma->vm_end; |
dc9aa5b9 | 360 | |
5b952b3c AK |
361 | if (endvma > end) |
362 | endvma = end; | |
363 | if (vma->vm_start > start) | |
364 | start = vma->vm_start; | |
dc9aa5b9 CL |
365 | err = check_pgd_range(vma, start, endvma, nodes, |
366 | flags, pagelist); | |
1da177e4 LT |
367 | if (err) { |
368 | first = ERR_PTR(err); | |
369 | break; | |
370 | } | |
371 | } | |
372 | prev = vma; | |
373 | } | |
374 | return first; | |
375 | } | |
376 | ||
377 | /* Apply policy to a single VMA */ | |
378 | static int policy_vma(struct vm_area_struct *vma, struct mempolicy *new) | |
379 | { | |
380 | int err = 0; | |
381 | struct mempolicy *old = vma->vm_policy; | |
382 | ||
383 | PDprintk("vma %lx-%lx/%lx vm_ops %p vm_file %p set_policy %p\n", | |
384 | vma->vm_start, vma->vm_end, vma->vm_pgoff, | |
385 | vma->vm_ops, vma->vm_file, | |
386 | vma->vm_ops ? vma->vm_ops->set_policy : NULL); | |
387 | ||
388 | if (vma->vm_ops && vma->vm_ops->set_policy) | |
389 | err = vma->vm_ops->set_policy(vma, new); | |
390 | if (!err) { | |
391 | mpol_get(new); | |
392 | vma->vm_policy = new; | |
393 | mpol_free(old); | |
394 | } | |
395 | return err; | |
396 | } | |
397 | ||
398 | /* Step 2: apply policy to a range and do splits. */ | |
399 | static int mbind_range(struct vm_area_struct *vma, unsigned long start, | |
400 | unsigned long end, struct mempolicy *new) | |
401 | { | |
402 | struct vm_area_struct *next; | |
403 | int err; | |
404 | ||
405 | err = 0; | |
406 | for (; vma && vma->vm_start < end; vma = next) { | |
407 | next = vma->vm_next; | |
408 | if (vma->vm_start < start) | |
409 | err = split_vma(vma->vm_mm, vma, start, 1); | |
410 | if (!err && vma->vm_end > end) | |
411 | err = split_vma(vma->vm_mm, vma, end, 0); | |
412 | if (!err) | |
413 | err = policy_vma(vma, new); | |
414 | if (err) | |
415 | break; | |
416 | } | |
417 | return err; | |
418 | } | |
419 | ||
8bccd85f CL |
420 | static int contextualize_policy(int mode, nodemask_t *nodes) |
421 | { | |
422 | if (!nodes) | |
423 | return 0; | |
424 | ||
425 | /* Update current mems_allowed */ | |
426 | cpuset_update_current_mems_allowed(); | |
427 | /* Ignore nodes not set in current->mems_allowed */ | |
428 | cpuset_restrict_to_mems_allowed(nodes->bits); | |
429 | return mpol_check_policy(mode, nodes); | |
430 | } | |
431 | ||
432 | long do_mbind(unsigned long start, unsigned long len, | |
433 | unsigned long mode, nodemask_t *nmask, unsigned long flags) | |
1da177e4 LT |
434 | { |
435 | struct vm_area_struct *vma; | |
436 | struct mm_struct *mm = current->mm; | |
437 | struct mempolicy *new; | |
438 | unsigned long end; | |
1da177e4 | 439 | int err; |
dc9aa5b9 | 440 | LIST_HEAD(pagelist); |
1da177e4 | 441 | |
dc9aa5b9 CL |
442 | if ((flags & ~(unsigned long)(MPOL_MF_STRICT|MPOL_MF_MOVE|MPOL_MF_MOVE_ALL)) |
443 | || mode > MPOL_MAX) | |
1da177e4 | 444 | return -EINVAL; |
dc9aa5b9 CL |
445 | if ((flags & MPOL_MF_MOVE_ALL) && !capable(CAP_SYS_RESOURCE)) |
446 | return -EPERM; | |
447 | ||
1da177e4 LT |
448 | if (start & ~PAGE_MASK) |
449 | return -EINVAL; | |
dc9aa5b9 | 450 | |
1da177e4 LT |
451 | if (mode == MPOL_DEFAULT) |
452 | flags &= ~MPOL_MF_STRICT; | |
dc9aa5b9 | 453 | |
1da177e4 LT |
454 | len = (len + PAGE_SIZE - 1) & PAGE_MASK; |
455 | end = start + len; | |
dc9aa5b9 | 456 | |
1da177e4 LT |
457 | if (end < start) |
458 | return -EINVAL; | |
459 | if (end == start) | |
460 | return 0; | |
dc9aa5b9 | 461 | |
5fcbb230 | 462 | if (mpol_check_policy(mode, nmask)) |
8bccd85f | 463 | return -EINVAL; |
dc9aa5b9 | 464 | |
8bccd85f | 465 | new = mpol_new(mode, nmask); |
1da177e4 LT |
466 | if (IS_ERR(new)) |
467 | return PTR_ERR(new); | |
468 | ||
dc9aa5b9 CL |
469 | /* |
470 | * If we are using the default policy then operation | |
471 | * on discontinuous address spaces is okay after all | |
472 | */ | |
473 | if (!new) | |
474 | flags |= MPOL_MF_DISCONTIG_OK; | |
475 | ||
1da177e4 | 476 | PDprintk("mbind %lx-%lx mode:%ld nodes:%lx\n",start,start+len, |
dfcd3c0d | 477 | mode,nodes_addr(nodes)[0]); |
1da177e4 LT |
478 | |
479 | down_write(&mm->mmap_sem); | |
dc9aa5b9 CL |
480 | vma = check_range(mm, start, end, nmask, flags, |
481 | (flags & (MPOL_MF_MOVE | MPOL_MF_MOVE_ALL)) ? &pagelist : NULL); | |
1da177e4 | 482 | err = PTR_ERR(vma); |
dc9aa5b9 | 483 | if (!IS_ERR(vma)) { |
1da177e4 | 484 | err = mbind_range(vma, start, end, new); |
dc9aa5b9 CL |
485 | if (!list_empty(&pagelist)) |
486 | migrate_pages(&pagelist, NULL); | |
487 | if (!err && !list_empty(&pagelist) && (flags & MPOL_MF_STRICT)) | |
488 | err = -EIO; | |
489 | } | |
490 | if (!list_empty(&pagelist)) | |
491 | putback_lru_pages(&pagelist); | |
492 | ||
1da177e4 LT |
493 | up_write(&mm->mmap_sem); |
494 | mpol_free(new); | |
495 | return err; | |
496 | } | |
497 | ||
498 | /* Set the process memory policy */ | |
8bccd85f | 499 | long do_set_mempolicy(int mode, nodemask_t *nodes) |
1da177e4 | 500 | { |
1da177e4 | 501 | struct mempolicy *new; |
1da177e4 | 502 | |
8bccd85f | 503 | if (contextualize_policy(mode, nodes)) |
1da177e4 | 504 | return -EINVAL; |
8bccd85f | 505 | new = mpol_new(mode, nodes); |
1da177e4 LT |
506 | if (IS_ERR(new)) |
507 | return PTR_ERR(new); | |
508 | mpol_free(current->mempolicy); | |
509 | current->mempolicy = new; | |
510 | if (new && new->policy == MPOL_INTERLEAVE) | |
dfcd3c0d | 511 | current->il_next = first_node(new->v.nodes); |
1da177e4 LT |
512 | return 0; |
513 | } | |
514 | ||
515 | /* Fill a zone bitmap for a policy */ | |
dfcd3c0d | 516 | static void get_zonemask(struct mempolicy *p, nodemask_t *nodes) |
1da177e4 LT |
517 | { |
518 | int i; | |
519 | ||
dfcd3c0d | 520 | nodes_clear(*nodes); |
1da177e4 LT |
521 | switch (p->policy) { |
522 | case MPOL_BIND: | |
523 | for (i = 0; p->v.zonelist->zones[i]; i++) | |
8bccd85f CL |
524 | node_set(p->v.zonelist->zones[i]->zone_pgdat->node_id, |
525 | *nodes); | |
1da177e4 LT |
526 | break; |
527 | case MPOL_DEFAULT: | |
528 | break; | |
529 | case MPOL_INTERLEAVE: | |
dfcd3c0d | 530 | *nodes = p->v.nodes; |
1da177e4 LT |
531 | break; |
532 | case MPOL_PREFERRED: | |
533 | /* or use current node instead of online map? */ | |
534 | if (p->v.preferred_node < 0) | |
dfcd3c0d | 535 | *nodes = node_online_map; |
1da177e4 | 536 | else |
dfcd3c0d | 537 | node_set(p->v.preferred_node, *nodes); |
1da177e4 LT |
538 | break; |
539 | default: | |
540 | BUG(); | |
541 | } | |
542 | } | |
543 | ||
544 | static int lookup_node(struct mm_struct *mm, unsigned long addr) | |
545 | { | |
546 | struct page *p; | |
547 | int err; | |
548 | ||
549 | err = get_user_pages(current, mm, addr & PAGE_MASK, 1, 0, 0, &p, NULL); | |
550 | if (err >= 0) { | |
551 | err = page_to_nid(p); | |
552 | put_page(p); | |
553 | } | |
554 | return err; | |
555 | } | |
556 | ||
1da177e4 | 557 | /* Retrieve NUMA policy */ |
8bccd85f CL |
558 | long do_get_mempolicy(int *policy, nodemask_t *nmask, |
559 | unsigned long addr, unsigned long flags) | |
1da177e4 | 560 | { |
8bccd85f | 561 | int err; |
1da177e4 LT |
562 | struct mm_struct *mm = current->mm; |
563 | struct vm_area_struct *vma = NULL; | |
564 | struct mempolicy *pol = current->mempolicy; | |
565 | ||
68860ec1 | 566 | cpuset_update_current_mems_allowed(); |
1da177e4 LT |
567 | if (flags & ~(unsigned long)(MPOL_F_NODE|MPOL_F_ADDR)) |
568 | return -EINVAL; | |
1da177e4 LT |
569 | if (flags & MPOL_F_ADDR) { |
570 | down_read(&mm->mmap_sem); | |
571 | vma = find_vma_intersection(mm, addr, addr+1); | |
572 | if (!vma) { | |
573 | up_read(&mm->mmap_sem); | |
574 | return -EFAULT; | |
575 | } | |
576 | if (vma->vm_ops && vma->vm_ops->get_policy) | |
577 | pol = vma->vm_ops->get_policy(vma, addr); | |
578 | else | |
579 | pol = vma->vm_policy; | |
580 | } else if (addr) | |
581 | return -EINVAL; | |
582 | ||
583 | if (!pol) | |
584 | pol = &default_policy; | |
585 | ||
586 | if (flags & MPOL_F_NODE) { | |
587 | if (flags & MPOL_F_ADDR) { | |
588 | err = lookup_node(mm, addr); | |
589 | if (err < 0) | |
590 | goto out; | |
8bccd85f | 591 | *policy = err; |
1da177e4 LT |
592 | } else if (pol == current->mempolicy && |
593 | pol->policy == MPOL_INTERLEAVE) { | |
8bccd85f | 594 | *policy = current->il_next; |
1da177e4 LT |
595 | } else { |
596 | err = -EINVAL; | |
597 | goto out; | |
598 | } | |
599 | } else | |
8bccd85f | 600 | *policy = pol->policy; |
1da177e4 LT |
601 | |
602 | if (vma) { | |
603 | up_read(¤t->mm->mmap_sem); | |
604 | vma = NULL; | |
605 | } | |
606 | ||
1da177e4 | 607 | err = 0; |
8bccd85f CL |
608 | if (nmask) |
609 | get_zonemask(pol, nmask); | |
1da177e4 LT |
610 | |
611 | out: | |
612 | if (vma) | |
613 | up_read(¤t->mm->mmap_sem); | |
614 | return err; | |
615 | } | |
616 | ||
39743889 CL |
617 | /* |
618 | * For now migrate_pages simply swaps out the pages from nodes that are in | |
619 | * the source set but not in the target set. In the future, we would | |
620 | * want a function that moves pages between the two nodesets in such | |
621 | * a way as to preserve the physical layout as much as possible. | |
622 | * | |
623 | * Returns the number of page that could not be moved. | |
624 | */ | |
625 | int do_migrate_pages(struct mm_struct *mm, | |
626 | const nodemask_t *from_nodes, const nodemask_t *to_nodes, int flags) | |
627 | { | |
628 | LIST_HEAD(pagelist); | |
629 | int count = 0; | |
630 | nodemask_t nodes; | |
631 | ||
632 | nodes_andnot(nodes, *from_nodes, *to_nodes); | |
633 | nodes_complement(nodes, nodes); | |
634 | ||
635 | down_read(&mm->mmap_sem); | |
636 | check_range(mm, mm->mmap->vm_start, TASK_SIZE, &nodes, | |
637 | flags | MPOL_MF_DISCONTIG_OK, &pagelist); | |
638 | if (!list_empty(&pagelist)) { | |
639 | migrate_pages(&pagelist, NULL); | |
640 | if (!list_empty(&pagelist)) | |
641 | count = putback_lru_pages(&pagelist); | |
642 | } | |
643 | up_read(&mm->mmap_sem); | |
644 | return count; | |
645 | } | |
646 | ||
8bccd85f CL |
647 | /* |
648 | * User space interface with variable sized bitmaps for nodelists. | |
649 | */ | |
650 | ||
651 | /* Copy a node mask from user space. */ | |
39743889 | 652 | static int get_nodes(nodemask_t *nodes, const unsigned long __user *nmask, |
8bccd85f CL |
653 | unsigned long maxnode) |
654 | { | |
655 | unsigned long k; | |
656 | unsigned long nlongs; | |
657 | unsigned long endmask; | |
658 | ||
659 | --maxnode; | |
660 | nodes_clear(*nodes); | |
661 | if (maxnode == 0 || !nmask) | |
662 | return 0; | |
663 | ||
664 | nlongs = BITS_TO_LONGS(maxnode); | |
665 | if ((maxnode % BITS_PER_LONG) == 0) | |
666 | endmask = ~0UL; | |
667 | else | |
668 | endmask = (1UL << (maxnode % BITS_PER_LONG)) - 1; | |
669 | ||
670 | /* When the user specified more nodes than supported just check | |
671 | if the non supported part is all zero. */ | |
672 | if (nlongs > BITS_TO_LONGS(MAX_NUMNODES)) { | |
673 | if (nlongs > PAGE_SIZE/sizeof(long)) | |
674 | return -EINVAL; | |
675 | for (k = BITS_TO_LONGS(MAX_NUMNODES); k < nlongs; k++) { | |
676 | unsigned long t; | |
677 | if (get_user(t, nmask + k)) | |
678 | return -EFAULT; | |
679 | if (k == nlongs - 1) { | |
680 | if (t & endmask) | |
681 | return -EINVAL; | |
682 | } else if (t) | |
683 | return -EINVAL; | |
684 | } | |
685 | nlongs = BITS_TO_LONGS(MAX_NUMNODES); | |
686 | endmask = ~0UL; | |
687 | } | |
688 | ||
689 | if (copy_from_user(nodes_addr(*nodes), nmask, nlongs*sizeof(unsigned long))) | |
690 | return -EFAULT; | |
691 | nodes_addr(*nodes)[nlongs-1] &= endmask; | |
692 | return 0; | |
693 | } | |
694 | ||
695 | /* Copy a kernel node mask to user space */ | |
696 | static int copy_nodes_to_user(unsigned long __user *mask, unsigned long maxnode, | |
697 | nodemask_t *nodes) | |
698 | { | |
699 | unsigned long copy = ALIGN(maxnode-1, 64) / 8; | |
700 | const int nbytes = BITS_TO_LONGS(MAX_NUMNODES) * sizeof(long); | |
701 | ||
702 | if (copy > nbytes) { | |
703 | if (copy > PAGE_SIZE) | |
704 | return -EINVAL; | |
705 | if (clear_user((char __user *)mask + nbytes, copy - nbytes)) | |
706 | return -EFAULT; | |
707 | copy = nbytes; | |
708 | } | |
709 | return copy_to_user(mask, nodes_addr(*nodes), copy) ? -EFAULT : 0; | |
710 | } | |
711 | ||
712 | asmlinkage long sys_mbind(unsigned long start, unsigned long len, | |
713 | unsigned long mode, | |
714 | unsigned long __user *nmask, unsigned long maxnode, | |
715 | unsigned flags) | |
716 | { | |
717 | nodemask_t nodes; | |
718 | int err; | |
719 | ||
720 | err = get_nodes(&nodes, nmask, maxnode); | |
721 | if (err) | |
722 | return err; | |
723 | return do_mbind(start, len, mode, &nodes, flags); | |
724 | } | |
725 | ||
726 | /* Set the process memory policy */ | |
727 | asmlinkage long sys_set_mempolicy(int mode, unsigned long __user *nmask, | |
728 | unsigned long maxnode) | |
729 | { | |
730 | int err; | |
731 | nodemask_t nodes; | |
732 | ||
733 | if (mode < 0 || mode > MPOL_MAX) | |
734 | return -EINVAL; | |
735 | err = get_nodes(&nodes, nmask, maxnode); | |
736 | if (err) | |
737 | return err; | |
738 | return do_set_mempolicy(mode, &nodes); | |
739 | } | |
740 | ||
39743889 CL |
741 | /* Macro needed until Paul implements this function in kernel/cpusets.c */ |
742 | #define cpuset_mems_allowed(task) node_online_map | |
743 | ||
744 | asmlinkage long sys_migrate_pages(pid_t pid, unsigned long maxnode, | |
745 | const unsigned long __user *old_nodes, | |
746 | const unsigned long __user *new_nodes) | |
747 | { | |
748 | struct mm_struct *mm; | |
749 | struct task_struct *task; | |
750 | nodemask_t old; | |
751 | nodemask_t new; | |
752 | nodemask_t task_nodes; | |
753 | int err; | |
754 | ||
755 | err = get_nodes(&old, old_nodes, maxnode); | |
756 | if (err) | |
757 | return err; | |
758 | ||
759 | err = get_nodes(&new, new_nodes, maxnode); | |
760 | if (err) | |
761 | return err; | |
762 | ||
763 | /* Find the mm_struct */ | |
764 | read_lock(&tasklist_lock); | |
765 | task = pid ? find_task_by_pid(pid) : current; | |
766 | if (!task) { | |
767 | read_unlock(&tasklist_lock); | |
768 | return -ESRCH; | |
769 | } | |
770 | mm = get_task_mm(task); | |
771 | read_unlock(&tasklist_lock); | |
772 | ||
773 | if (!mm) | |
774 | return -EINVAL; | |
775 | ||
776 | /* | |
777 | * Check if this process has the right to modify the specified | |
778 | * process. The right exists if the process has administrative | |
779 | * capabilities, superuser priviledges or the same | |
780 | * userid as the target process. | |
781 | */ | |
782 | if ((current->euid != task->suid) && (current->euid != task->uid) && | |
783 | (current->uid != task->suid) && (current->uid != task->uid) && | |
784 | !capable(CAP_SYS_ADMIN)) { | |
785 | err = -EPERM; | |
786 | goto out; | |
787 | } | |
788 | ||
789 | task_nodes = cpuset_mems_allowed(task); | |
790 | /* Is the user allowed to access the target nodes? */ | |
791 | if (!nodes_subset(new, task_nodes) && !capable(CAP_SYS_ADMIN)) { | |
792 | err = -EPERM; | |
793 | goto out; | |
794 | } | |
795 | ||
796 | err = do_migrate_pages(mm, &old, &new, MPOL_MF_MOVE); | |
797 | out: | |
798 | mmput(mm); | |
799 | return err; | |
800 | } | |
801 | ||
802 | ||
8bccd85f CL |
803 | /* Retrieve NUMA policy */ |
804 | asmlinkage long sys_get_mempolicy(int __user *policy, | |
805 | unsigned long __user *nmask, | |
806 | unsigned long maxnode, | |
807 | unsigned long addr, unsigned long flags) | |
808 | { | |
809 | int err, pval; | |
810 | nodemask_t nodes; | |
811 | ||
812 | if (nmask != NULL && maxnode < MAX_NUMNODES) | |
813 | return -EINVAL; | |
814 | ||
815 | err = do_get_mempolicy(&pval, &nodes, addr, flags); | |
816 | ||
817 | if (err) | |
818 | return err; | |
819 | ||
820 | if (policy && put_user(pval, policy)) | |
821 | return -EFAULT; | |
822 | ||
823 | if (nmask) | |
824 | err = copy_nodes_to_user(nmask, maxnode, &nodes); | |
825 | ||
826 | return err; | |
827 | } | |
828 | ||
1da177e4 LT |
829 | #ifdef CONFIG_COMPAT |
830 | ||
831 | asmlinkage long compat_sys_get_mempolicy(int __user *policy, | |
832 | compat_ulong_t __user *nmask, | |
833 | compat_ulong_t maxnode, | |
834 | compat_ulong_t addr, compat_ulong_t flags) | |
835 | { | |
836 | long err; | |
837 | unsigned long __user *nm = NULL; | |
838 | unsigned long nr_bits, alloc_size; | |
839 | DECLARE_BITMAP(bm, MAX_NUMNODES); | |
840 | ||
841 | nr_bits = min_t(unsigned long, maxnode-1, MAX_NUMNODES); | |
842 | alloc_size = ALIGN(nr_bits, BITS_PER_LONG) / 8; | |
843 | ||
844 | if (nmask) | |
845 | nm = compat_alloc_user_space(alloc_size); | |
846 | ||
847 | err = sys_get_mempolicy(policy, nm, nr_bits+1, addr, flags); | |
848 | ||
849 | if (!err && nmask) { | |
850 | err = copy_from_user(bm, nm, alloc_size); | |
851 | /* ensure entire bitmap is zeroed */ | |
852 | err |= clear_user(nmask, ALIGN(maxnode-1, 8) / 8); | |
853 | err |= compat_put_bitmap(nmask, bm, nr_bits); | |
854 | } | |
855 | ||
856 | return err; | |
857 | } | |
858 | ||
859 | asmlinkage long compat_sys_set_mempolicy(int mode, compat_ulong_t __user *nmask, | |
860 | compat_ulong_t maxnode) | |
861 | { | |
862 | long err = 0; | |
863 | unsigned long __user *nm = NULL; | |
864 | unsigned long nr_bits, alloc_size; | |
865 | DECLARE_BITMAP(bm, MAX_NUMNODES); | |
866 | ||
867 | nr_bits = min_t(unsigned long, maxnode-1, MAX_NUMNODES); | |
868 | alloc_size = ALIGN(nr_bits, BITS_PER_LONG) / 8; | |
869 | ||
870 | if (nmask) { | |
871 | err = compat_get_bitmap(bm, nmask, nr_bits); | |
872 | nm = compat_alloc_user_space(alloc_size); | |
873 | err |= copy_to_user(nm, bm, alloc_size); | |
874 | } | |
875 | ||
876 | if (err) | |
877 | return -EFAULT; | |
878 | ||
879 | return sys_set_mempolicy(mode, nm, nr_bits+1); | |
880 | } | |
881 | ||
882 | asmlinkage long compat_sys_mbind(compat_ulong_t start, compat_ulong_t len, | |
883 | compat_ulong_t mode, compat_ulong_t __user *nmask, | |
884 | compat_ulong_t maxnode, compat_ulong_t flags) | |
885 | { | |
886 | long err = 0; | |
887 | unsigned long __user *nm = NULL; | |
888 | unsigned long nr_bits, alloc_size; | |
dfcd3c0d | 889 | nodemask_t bm; |
1da177e4 LT |
890 | |
891 | nr_bits = min_t(unsigned long, maxnode-1, MAX_NUMNODES); | |
892 | alloc_size = ALIGN(nr_bits, BITS_PER_LONG) / 8; | |
893 | ||
894 | if (nmask) { | |
dfcd3c0d | 895 | err = compat_get_bitmap(nodes_addr(bm), nmask, nr_bits); |
1da177e4 | 896 | nm = compat_alloc_user_space(alloc_size); |
dfcd3c0d | 897 | err |= copy_to_user(nm, nodes_addr(bm), alloc_size); |
1da177e4 LT |
898 | } |
899 | ||
900 | if (err) | |
901 | return -EFAULT; | |
902 | ||
903 | return sys_mbind(start, len, mode, nm, nr_bits+1, flags); | |
904 | } | |
905 | ||
906 | #endif | |
907 | ||
908 | /* Return effective policy for a VMA */ | |
6e21c8f1 CL |
909 | struct mempolicy * |
910 | get_vma_policy(struct task_struct *task, struct vm_area_struct *vma, unsigned long addr) | |
1da177e4 | 911 | { |
6e21c8f1 | 912 | struct mempolicy *pol = task->mempolicy; |
1da177e4 LT |
913 | |
914 | if (vma) { | |
915 | if (vma->vm_ops && vma->vm_ops->get_policy) | |
8bccd85f | 916 | pol = vma->vm_ops->get_policy(vma, addr); |
1da177e4 LT |
917 | else if (vma->vm_policy && |
918 | vma->vm_policy->policy != MPOL_DEFAULT) | |
919 | pol = vma->vm_policy; | |
920 | } | |
921 | if (!pol) | |
922 | pol = &default_policy; | |
923 | return pol; | |
924 | } | |
925 | ||
926 | /* Return a zonelist representing a mempolicy */ | |
dd0fc66f | 927 | static struct zonelist *zonelist_policy(gfp_t gfp, struct mempolicy *policy) |
1da177e4 LT |
928 | { |
929 | int nd; | |
930 | ||
931 | switch (policy->policy) { | |
932 | case MPOL_PREFERRED: | |
933 | nd = policy->v.preferred_node; | |
934 | if (nd < 0) | |
935 | nd = numa_node_id(); | |
936 | break; | |
937 | case MPOL_BIND: | |
938 | /* Lower zones don't get a policy applied */ | |
939 | /* Careful: current->mems_allowed might have moved */ | |
af4ca457 | 940 | if (gfp_zone(gfp) >= policy_zone) |
1da177e4 LT |
941 | if (cpuset_zonelist_valid_mems_allowed(policy->v.zonelist)) |
942 | return policy->v.zonelist; | |
943 | /*FALL THROUGH*/ | |
944 | case MPOL_INTERLEAVE: /* should not happen */ | |
945 | case MPOL_DEFAULT: | |
946 | nd = numa_node_id(); | |
947 | break; | |
948 | default: | |
949 | nd = 0; | |
950 | BUG(); | |
951 | } | |
af4ca457 | 952 | return NODE_DATA(nd)->node_zonelists + gfp_zone(gfp); |
1da177e4 LT |
953 | } |
954 | ||
955 | /* Do dynamic interleaving for a process */ | |
956 | static unsigned interleave_nodes(struct mempolicy *policy) | |
957 | { | |
958 | unsigned nid, next; | |
959 | struct task_struct *me = current; | |
960 | ||
961 | nid = me->il_next; | |
dfcd3c0d | 962 | next = next_node(nid, policy->v.nodes); |
1da177e4 | 963 | if (next >= MAX_NUMNODES) |
dfcd3c0d | 964 | next = first_node(policy->v.nodes); |
1da177e4 LT |
965 | me->il_next = next; |
966 | return nid; | |
967 | } | |
968 | ||
969 | /* Do static interleaving for a VMA with known offset. */ | |
970 | static unsigned offset_il_node(struct mempolicy *pol, | |
971 | struct vm_area_struct *vma, unsigned long off) | |
972 | { | |
dfcd3c0d | 973 | unsigned nnodes = nodes_weight(pol->v.nodes); |
1da177e4 LT |
974 | unsigned target = (unsigned)off % nnodes; |
975 | int c; | |
976 | int nid = -1; | |
977 | ||
978 | c = 0; | |
979 | do { | |
dfcd3c0d | 980 | nid = next_node(nid, pol->v.nodes); |
1da177e4 LT |
981 | c++; |
982 | } while (c <= target); | |
1da177e4 LT |
983 | return nid; |
984 | } | |
985 | ||
5da7ca86 CL |
986 | /* Determine a node number for interleave */ |
987 | static inline unsigned interleave_nid(struct mempolicy *pol, | |
988 | struct vm_area_struct *vma, unsigned long addr, int shift) | |
989 | { | |
990 | if (vma) { | |
991 | unsigned long off; | |
992 | ||
993 | off = vma->vm_pgoff; | |
994 | off += (addr - vma->vm_start) >> shift; | |
995 | return offset_il_node(pol, vma, off); | |
996 | } else | |
997 | return interleave_nodes(pol); | |
998 | } | |
999 | ||
1000 | /* Return a zonelist suitable for a huge page allocation. */ | |
1001 | struct zonelist *huge_zonelist(struct vm_area_struct *vma, unsigned long addr) | |
1002 | { | |
1003 | struct mempolicy *pol = get_vma_policy(current, vma, addr); | |
1004 | ||
1005 | if (pol->policy == MPOL_INTERLEAVE) { | |
1006 | unsigned nid; | |
1007 | ||
1008 | nid = interleave_nid(pol, vma, addr, HPAGE_SHIFT); | |
1009 | return NODE_DATA(nid)->node_zonelists + gfp_zone(GFP_HIGHUSER); | |
1010 | } | |
1011 | return zonelist_policy(GFP_HIGHUSER, pol); | |
1012 | } | |
1013 | ||
1da177e4 LT |
1014 | /* Allocate a page in interleaved policy. |
1015 | Own path because it needs to do special accounting. */ | |
662f3a0b AK |
1016 | static struct page *alloc_page_interleave(gfp_t gfp, unsigned order, |
1017 | unsigned nid) | |
1da177e4 LT |
1018 | { |
1019 | struct zonelist *zl; | |
1020 | struct page *page; | |
1021 | ||
af4ca457 | 1022 | zl = NODE_DATA(nid)->node_zonelists + gfp_zone(gfp); |
1da177e4 LT |
1023 | page = __alloc_pages(gfp, order, zl); |
1024 | if (page && page_zone(page) == zl->zones[0]) { | |
e7c8d5c9 | 1025 | zone_pcp(zl->zones[0],get_cpu())->interleave_hit++; |
1da177e4 LT |
1026 | put_cpu(); |
1027 | } | |
1028 | return page; | |
1029 | } | |
1030 | ||
1031 | /** | |
1032 | * alloc_page_vma - Allocate a page for a VMA. | |
1033 | * | |
1034 | * @gfp: | |
1035 | * %GFP_USER user allocation. | |
1036 | * %GFP_KERNEL kernel allocations, | |
1037 | * %GFP_HIGHMEM highmem/user allocations, | |
1038 | * %GFP_FS allocation should not call back into a file system. | |
1039 | * %GFP_ATOMIC don't sleep. | |
1040 | * | |
1041 | * @vma: Pointer to VMA or NULL if not available. | |
1042 | * @addr: Virtual Address of the allocation. Must be inside the VMA. | |
1043 | * | |
1044 | * This function allocates a page from the kernel page pool and applies | |
1045 | * a NUMA policy associated with the VMA or the current process. | |
1046 | * When VMA is not NULL caller must hold down_read on the mmap_sem of the | |
1047 | * mm_struct of the VMA to prevent it from going away. Should be used for | |
1048 | * all allocations for pages that will be mapped into | |
1049 | * user space. Returns NULL when no page can be allocated. | |
1050 | * | |
1051 | * Should be called with the mm_sem of the vma hold. | |
1052 | */ | |
1053 | struct page * | |
dd0fc66f | 1054 | alloc_page_vma(gfp_t gfp, struct vm_area_struct *vma, unsigned long addr) |
1da177e4 | 1055 | { |
6e21c8f1 | 1056 | struct mempolicy *pol = get_vma_policy(current, vma, addr); |
1da177e4 LT |
1057 | |
1058 | cpuset_update_current_mems_allowed(); | |
1059 | ||
1060 | if (unlikely(pol->policy == MPOL_INTERLEAVE)) { | |
1061 | unsigned nid; | |
5da7ca86 CL |
1062 | |
1063 | nid = interleave_nid(pol, vma, addr, PAGE_SHIFT); | |
1da177e4 LT |
1064 | return alloc_page_interleave(gfp, 0, nid); |
1065 | } | |
1066 | return __alloc_pages(gfp, 0, zonelist_policy(gfp, pol)); | |
1067 | } | |
1068 | ||
1069 | /** | |
1070 | * alloc_pages_current - Allocate pages. | |
1071 | * | |
1072 | * @gfp: | |
1073 | * %GFP_USER user allocation, | |
1074 | * %GFP_KERNEL kernel allocation, | |
1075 | * %GFP_HIGHMEM highmem allocation, | |
1076 | * %GFP_FS don't call back into a file system. | |
1077 | * %GFP_ATOMIC don't sleep. | |
1078 | * @order: Power of two of allocation size in pages. 0 is a single page. | |
1079 | * | |
1080 | * Allocate a page from the kernel page pool. When not in | |
1081 | * interrupt context and apply the current process NUMA policy. | |
1082 | * Returns NULL when no page can be allocated. | |
1083 | * | |
1084 | * Don't call cpuset_update_current_mems_allowed() unless | |
1085 | * 1) it's ok to take cpuset_sem (can WAIT), and | |
1086 | * 2) allocating for current task (not interrupt). | |
1087 | */ | |
dd0fc66f | 1088 | struct page *alloc_pages_current(gfp_t gfp, unsigned order) |
1da177e4 LT |
1089 | { |
1090 | struct mempolicy *pol = current->mempolicy; | |
1091 | ||
1092 | if ((gfp & __GFP_WAIT) && !in_interrupt()) | |
1093 | cpuset_update_current_mems_allowed(); | |
1094 | if (!pol || in_interrupt()) | |
1095 | pol = &default_policy; | |
1096 | if (pol->policy == MPOL_INTERLEAVE) | |
1097 | return alloc_page_interleave(gfp, order, interleave_nodes(pol)); | |
1098 | return __alloc_pages(gfp, order, zonelist_policy(gfp, pol)); | |
1099 | } | |
1100 | EXPORT_SYMBOL(alloc_pages_current); | |
1101 | ||
1102 | /* Slow path of a mempolicy copy */ | |
1103 | struct mempolicy *__mpol_copy(struct mempolicy *old) | |
1104 | { | |
1105 | struct mempolicy *new = kmem_cache_alloc(policy_cache, GFP_KERNEL); | |
1106 | ||
1107 | if (!new) | |
1108 | return ERR_PTR(-ENOMEM); | |
1109 | *new = *old; | |
1110 | atomic_set(&new->refcnt, 1); | |
1111 | if (new->policy == MPOL_BIND) { | |
1112 | int sz = ksize(old->v.zonelist); | |
1113 | new->v.zonelist = kmalloc(sz, SLAB_KERNEL); | |
1114 | if (!new->v.zonelist) { | |
1115 | kmem_cache_free(policy_cache, new); | |
1116 | return ERR_PTR(-ENOMEM); | |
1117 | } | |
1118 | memcpy(new->v.zonelist, old->v.zonelist, sz); | |
1119 | } | |
1120 | return new; | |
1121 | } | |
1122 | ||
1123 | /* Slow path of a mempolicy comparison */ | |
1124 | int __mpol_equal(struct mempolicy *a, struct mempolicy *b) | |
1125 | { | |
1126 | if (!a || !b) | |
1127 | return 0; | |
1128 | if (a->policy != b->policy) | |
1129 | return 0; | |
1130 | switch (a->policy) { | |
1131 | case MPOL_DEFAULT: | |
1132 | return 1; | |
1133 | case MPOL_INTERLEAVE: | |
dfcd3c0d | 1134 | return nodes_equal(a->v.nodes, b->v.nodes); |
1da177e4 LT |
1135 | case MPOL_PREFERRED: |
1136 | return a->v.preferred_node == b->v.preferred_node; | |
1137 | case MPOL_BIND: { | |
1138 | int i; | |
1139 | for (i = 0; a->v.zonelist->zones[i]; i++) | |
1140 | if (a->v.zonelist->zones[i] != b->v.zonelist->zones[i]) | |
1141 | return 0; | |
1142 | return b->v.zonelist->zones[i] == NULL; | |
1143 | } | |
1144 | default: | |
1145 | BUG(); | |
1146 | return 0; | |
1147 | } | |
1148 | } | |
1149 | ||
1150 | /* Slow path of a mpol destructor. */ | |
1151 | void __mpol_free(struct mempolicy *p) | |
1152 | { | |
1153 | if (!atomic_dec_and_test(&p->refcnt)) | |
1154 | return; | |
1155 | if (p->policy == MPOL_BIND) | |
1156 | kfree(p->v.zonelist); | |
1157 | p->policy = MPOL_DEFAULT; | |
1158 | kmem_cache_free(policy_cache, p); | |
1159 | } | |
1160 | ||
1da177e4 LT |
1161 | /* |
1162 | * Shared memory backing store policy support. | |
1163 | * | |
1164 | * Remember policies even when nobody has shared memory mapped. | |
1165 | * The policies are kept in Red-Black tree linked from the inode. | |
1166 | * They are protected by the sp->lock spinlock, which should be held | |
1167 | * for any accesses to the tree. | |
1168 | */ | |
1169 | ||
1170 | /* lookup first element intersecting start-end */ | |
1171 | /* Caller holds sp->lock */ | |
1172 | static struct sp_node * | |
1173 | sp_lookup(struct shared_policy *sp, unsigned long start, unsigned long end) | |
1174 | { | |
1175 | struct rb_node *n = sp->root.rb_node; | |
1176 | ||
1177 | while (n) { | |
1178 | struct sp_node *p = rb_entry(n, struct sp_node, nd); | |
1179 | ||
1180 | if (start >= p->end) | |
1181 | n = n->rb_right; | |
1182 | else if (end <= p->start) | |
1183 | n = n->rb_left; | |
1184 | else | |
1185 | break; | |
1186 | } | |
1187 | if (!n) | |
1188 | return NULL; | |
1189 | for (;;) { | |
1190 | struct sp_node *w = NULL; | |
1191 | struct rb_node *prev = rb_prev(n); | |
1192 | if (!prev) | |
1193 | break; | |
1194 | w = rb_entry(prev, struct sp_node, nd); | |
1195 | if (w->end <= start) | |
1196 | break; | |
1197 | n = prev; | |
1198 | } | |
1199 | return rb_entry(n, struct sp_node, nd); | |
1200 | } | |
1201 | ||
1202 | /* Insert a new shared policy into the list. */ | |
1203 | /* Caller holds sp->lock */ | |
1204 | static void sp_insert(struct shared_policy *sp, struct sp_node *new) | |
1205 | { | |
1206 | struct rb_node **p = &sp->root.rb_node; | |
1207 | struct rb_node *parent = NULL; | |
1208 | struct sp_node *nd; | |
1209 | ||
1210 | while (*p) { | |
1211 | parent = *p; | |
1212 | nd = rb_entry(parent, struct sp_node, nd); | |
1213 | if (new->start < nd->start) | |
1214 | p = &(*p)->rb_left; | |
1215 | else if (new->end > nd->end) | |
1216 | p = &(*p)->rb_right; | |
1217 | else | |
1218 | BUG(); | |
1219 | } | |
1220 | rb_link_node(&new->nd, parent, p); | |
1221 | rb_insert_color(&new->nd, &sp->root); | |
1222 | PDprintk("inserting %lx-%lx: %d\n", new->start, new->end, | |
1223 | new->policy ? new->policy->policy : 0); | |
1224 | } | |
1225 | ||
1226 | /* Find shared policy intersecting idx */ | |
1227 | struct mempolicy * | |
1228 | mpol_shared_policy_lookup(struct shared_policy *sp, unsigned long idx) | |
1229 | { | |
1230 | struct mempolicy *pol = NULL; | |
1231 | struct sp_node *sn; | |
1232 | ||
1233 | if (!sp->root.rb_node) | |
1234 | return NULL; | |
1235 | spin_lock(&sp->lock); | |
1236 | sn = sp_lookup(sp, idx, idx+1); | |
1237 | if (sn) { | |
1238 | mpol_get(sn->policy); | |
1239 | pol = sn->policy; | |
1240 | } | |
1241 | spin_unlock(&sp->lock); | |
1242 | return pol; | |
1243 | } | |
1244 | ||
1245 | static void sp_delete(struct shared_policy *sp, struct sp_node *n) | |
1246 | { | |
1247 | PDprintk("deleting %lx-l%x\n", n->start, n->end); | |
1248 | rb_erase(&n->nd, &sp->root); | |
1249 | mpol_free(n->policy); | |
1250 | kmem_cache_free(sn_cache, n); | |
1251 | } | |
1252 | ||
1253 | struct sp_node * | |
1254 | sp_alloc(unsigned long start, unsigned long end, struct mempolicy *pol) | |
1255 | { | |
1256 | struct sp_node *n = kmem_cache_alloc(sn_cache, GFP_KERNEL); | |
1257 | ||
1258 | if (!n) | |
1259 | return NULL; | |
1260 | n->start = start; | |
1261 | n->end = end; | |
1262 | mpol_get(pol); | |
1263 | n->policy = pol; | |
1264 | return n; | |
1265 | } | |
1266 | ||
1267 | /* Replace a policy range. */ | |
1268 | static int shared_policy_replace(struct shared_policy *sp, unsigned long start, | |
1269 | unsigned long end, struct sp_node *new) | |
1270 | { | |
1271 | struct sp_node *n, *new2 = NULL; | |
1272 | ||
1273 | restart: | |
1274 | spin_lock(&sp->lock); | |
1275 | n = sp_lookup(sp, start, end); | |
1276 | /* Take care of old policies in the same range. */ | |
1277 | while (n && n->start < end) { | |
1278 | struct rb_node *next = rb_next(&n->nd); | |
1279 | if (n->start >= start) { | |
1280 | if (n->end <= end) | |
1281 | sp_delete(sp, n); | |
1282 | else | |
1283 | n->start = end; | |
1284 | } else { | |
1285 | /* Old policy spanning whole new range. */ | |
1286 | if (n->end > end) { | |
1287 | if (!new2) { | |
1288 | spin_unlock(&sp->lock); | |
1289 | new2 = sp_alloc(end, n->end, n->policy); | |
1290 | if (!new2) | |
1291 | return -ENOMEM; | |
1292 | goto restart; | |
1293 | } | |
1294 | n->end = start; | |
1295 | sp_insert(sp, new2); | |
1296 | new2 = NULL; | |
1297 | break; | |
1298 | } else | |
1299 | n->end = start; | |
1300 | } | |
1301 | if (!next) | |
1302 | break; | |
1303 | n = rb_entry(next, struct sp_node, nd); | |
1304 | } | |
1305 | if (new) | |
1306 | sp_insert(sp, new); | |
1307 | spin_unlock(&sp->lock); | |
1308 | if (new2) { | |
1309 | mpol_free(new2->policy); | |
1310 | kmem_cache_free(sn_cache, new2); | |
1311 | } | |
1312 | return 0; | |
1313 | } | |
1314 | ||
1315 | int mpol_set_shared_policy(struct shared_policy *info, | |
1316 | struct vm_area_struct *vma, struct mempolicy *npol) | |
1317 | { | |
1318 | int err; | |
1319 | struct sp_node *new = NULL; | |
1320 | unsigned long sz = vma_pages(vma); | |
1321 | ||
1322 | PDprintk("set_shared_policy %lx sz %lu %d %lx\n", | |
1323 | vma->vm_pgoff, | |
1324 | sz, npol? npol->policy : -1, | |
dfcd3c0d | 1325 | npol ? nodes_addr(npol->v.nodes)[0] : -1); |
1da177e4 LT |
1326 | |
1327 | if (npol) { | |
1328 | new = sp_alloc(vma->vm_pgoff, vma->vm_pgoff + sz, npol); | |
1329 | if (!new) | |
1330 | return -ENOMEM; | |
1331 | } | |
1332 | err = shared_policy_replace(info, vma->vm_pgoff, vma->vm_pgoff+sz, new); | |
1333 | if (err && new) | |
1334 | kmem_cache_free(sn_cache, new); | |
1335 | return err; | |
1336 | } | |
1337 | ||
1338 | /* Free a backing policy store on inode delete. */ | |
1339 | void mpol_free_shared_policy(struct shared_policy *p) | |
1340 | { | |
1341 | struct sp_node *n; | |
1342 | struct rb_node *next; | |
1343 | ||
1344 | if (!p->root.rb_node) | |
1345 | return; | |
1346 | spin_lock(&p->lock); | |
1347 | next = rb_first(&p->root); | |
1348 | while (next) { | |
1349 | n = rb_entry(next, struct sp_node, nd); | |
1350 | next = rb_next(&n->nd); | |
90c5029e | 1351 | rb_erase(&n->nd, &p->root); |
1da177e4 LT |
1352 | mpol_free(n->policy); |
1353 | kmem_cache_free(sn_cache, n); | |
1354 | } | |
1355 | spin_unlock(&p->lock); | |
1da177e4 LT |
1356 | } |
1357 | ||
1358 | /* assumes fs == KERNEL_DS */ | |
1359 | void __init numa_policy_init(void) | |
1360 | { | |
1361 | policy_cache = kmem_cache_create("numa_policy", | |
1362 | sizeof(struct mempolicy), | |
1363 | 0, SLAB_PANIC, NULL, NULL); | |
1364 | ||
1365 | sn_cache = kmem_cache_create("shared_policy_node", | |
1366 | sizeof(struct sp_node), | |
1367 | 0, SLAB_PANIC, NULL, NULL); | |
1368 | ||
1369 | /* Set interleaving policy for system init. This way not all | |
1370 | the data structures allocated at system boot end up in node zero. */ | |
1371 | ||
8bccd85f | 1372 | if (do_set_mempolicy(MPOL_INTERLEAVE, &node_online_map)) |
1da177e4 LT |
1373 | printk("numa_policy_init: interleaving failed\n"); |
1374 | } | |
1375 | ||
8bccd85f | 1376 | /* Reset policy of current process to default */ |
1da177e4 LT |
1377 | void numa_default_policy(void) |
1378 | { | |
8bccd85f | 1379 | do_set_mempolicy(MPOL_DEFAULT, NULL); |
1da177e4 | 1380 | } |
68860ec1 PJ |
1381 | |
1382 | /* Migrate a policy to a different set of nodes */ | |
1383 | static void rebind_policy(struct mempolicy *pol, const nodemask_t *old, | |
1384 | const nodemask_t *new) | |
1385 | { | |
1386 | nodemask_t tmp; | |
1387 | ||
1388 | if (!pol) | |
1389 | return; | |
1390 | ||
1391 | switch (pol->policy) { | |
1392 | case MPOL_DEFAULT: | |
1393 | break; | |
1394 | case MPOL_INTERLEAVE: | |
1395 | nodes_remap(tmp, pol->v.nodes, *old, *new); | |
1396 | pol->v.nodes = tmp; | |
1397 | current->il_next = node_remap(current->il_next, *old, *new); | |
1398 | break; | |
1399 | case MPOL_PREFERRED: | |
1400 | pol->v.preferred_node = node_remap(pol->v.preferred_node, | |
1401 | *old, *new); | |
1402 | break; | |
1403 | case MPOL_BIND: { | |
1404 | nodemask_t nodes; | |
1405 | struct zone **z; | |
1406 | struct zonelist *zonelist; | |
1407 | ||
1408 | nodes_clear(nodes); | |
1409 | for (z = pol->v.zonelist->zones; *z; z++) | |
1410 | node_set((*z)->zone_pgdat->node_id, nodes); | |
1411 | nodes_remap(tmp, nodes, *old, *new); | |
1412 | nodes = tmp; | |
1413 | ||
1414 | zonelist = bind_zonelist(&nodes); | |
1415 | ||
1416 | /* If no mem, then zonelist is NULL and we keep old zonelist. | |
1417 | * If that old zonelist has no remaining mems_allowed nodes, | |
1418 | * then zonelist_policy() will "FALL THROUGH" to MPOL_DEFAULT. | |
1419 | */ | |
1420 | ||
1421 | if (zonelist) { | |
1422 | /* Good - got mem - substitute new zonelist */ | |
1423 | kfree(pol->v.zonelist); | |
1424 | pol->v.zonelist = zonelist; | |
1425 | } | |
1426 | break; | |
1427 | } | |
1428 | default: | |
1429 | BUG(); | |
1430 | break; | |
1431 | } | |
1432 | } | |
1433 | ||
1434 | /* | |
1435 | * Someone moved this task to different nodes. Fixup mempolicies. | |
1436 | * | |
1437 | * TODO - fixup current->mm->vma and shmfs/tmpfs/hugetlbfs policies as well, | |
1438 | * once we have a cpuset mechanism to mark which cpuset subtree is migrating. | |
1439 | */ | |
1440 | void numa_policy_rebind(const nodemask_t *old, const nodemask_t *new) | |
1441 | { | |
1442 | rebind_policy(current->mempolicy, old, new); | |
1443 | } |