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46aeb7e6 | 1 | // SPDX-License-Identifier: GPL-2.0-only |
1da177e4 LT |
2 | /* |
3 | * Simple NUMA memory policy for the Linux kernel. | |
4 | * | |
5 | * Copyright 2003,2004 Andi Kleen, SuSE Labs. | |
8bccd85f | 6 | * (C) Copyright 2005 Christoph Lameter, Silicon Graphics, Inc. |
1da177e4 LT |
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 | 28 | * preferred Try a specific node first before normal fallback. |
00ef2d2f | 29 | * As a special case NUMA_NO_NODE here means do the allocation |
1da177e4 LT |
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 | * |
b27abacc DH |
34 | * preferred many Try a set of nodes first before normal fallback. This is |
35 | * similar to preferred without the special case. | |
36 | * | |
1da177e4 LT |
37 | * default Allocate on the local node first, or when on a VMA |
38 | * use the process policy. This is what Linux always did | |
39 | * in a NUMA aware kernel and still does by, ahem, default. | |
40 | * | |
41 | * The process policy is applied for most non interrupt memory allocations | |
42 | * in that process' context. Interrupts ignore the policies and always | |
43 | * try to allocate on the local CPU. The VMA policy is only applied for memory | |
44 | * allocations for a VMA in the VM. | |
45 | * | |
46 | * Currently there are a few corner cases in swapping where the policy | |
47 | * is not applied, but the majority should be handled. When process policy | |
48 | * is used it is not remembered over swap outs/swap ins. | |
49 | * | |
50 | * Only the highest zone in the zone hierarchy gets policied. Allocations | |
51 | * requesting a lower zone just use default policy. This implies that | |
52 | * on systems with highmem kernel lowmem allocation don't get policied. | |
53 | * Same with GFP_DMA allocations. | |
54 | * | |
55 | * For shmfs/tmpfs/hugetlbfs shared memory the policy is shared between | |
56 | * all users and remembered even when nobody has memory mapped. | |
57 | */ | |
58 | ||
59 | /* Notebook: | |
60 | fix mmap readahead to honour policy and enable policy for any page cache | |
61 | object | |
62 | statistics for bigpages | |
63 | global policy for page cache? currently it uses process policy. Requires | |
64 | first item above. | |
65 | handle mremap for shared memory (currently ignored for the policy) | |
66 | grows down? | |
67 | make bind policy root only? It can trigger oom much faster and the | |
68 | kernel is not always grateful with that. | |
1da177e4 LT |
69 | */ |
70 | ||
b1de0d13 MH |
71 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
72 | ||
1da177e4 | 73 | #include <linux/mempolicy.h> |
a520110e | 74 | #include <linux/pagewalk.h> |
1da177e4 LT |
75 | #include <linux/highmem.h> |
76 | #include <linux/hugetlb.h> | |
77 | #include <linux/kernel.h> | |
78 | #include <linux/sched.h> | |
6e84f315 | 79 | #include <linux/sched/mm.h> |
6a3827d7 | 80 | #include <linux/sched/numa_balancing.h> |
f719ff9b | 81 | #include <linux/sched/task.h> |
1da177e4 LT |
82 | #include <linux/nodemask.h> |
83 | #include <linux/cpuset.h> | |
1da177e4 LT |
84 | #include <linux/slab.h> |
85 | #include <linux/string.h> | |
b95f1b31 | 86 | #include <linux/export.h> |
b488893a | 87 | #include <linux/nsproxy.h> |
1da177e4 LT |
88 | #include <linux/interrupt.h> |
89 | #include <linux/init.h> | |
90 | #include <linux/compat.h> | |
31367466 | 91 | #include <linux/ptrace.h> |
dc9aa5b9 | 92 | #include <linux/swap.h> |
1a75a6c8 CL |
93 | #include <linux/seq_file.h> |
94 | #include <linux/proc_fs.h> | |
b20a3503 | 95 | #include <linux/migrate.h> |
62b61f61 | 96 | #include <linux/ksm.h> |
95a402c3 | 97 | #include <linux/rmap.h> |
86c3a764 | 98 | #include <linux/security.h> |
dbcb0f19 | 99 | #include <linux/syscalls.h> |
095f1fc4 | 100 | #include <linux/ctype.h> |
6d9c285a | 101 | #include <linux/mm_inline.h> |
b24f53a0 | 102 | #include <linux/mmu_notifier.h> |
b1de0d13 | 103 | #include <linux/printk.h> |
c8633798 | 104 | #include <linux/swapops.h> |
dc9aa5b9 | 105 | |
1da177e4 | 106 | #include <asm/tlbflush.h> |
7c0f6ba6 | 107 | #include <linux/uaccess.h> |
1da177e4 | 108 | |
62695a84 NP |
109 | #include "internal.h" |
110 | ||
38e35860 | 111 | /* Internal flags */ |
dc9aa5b9 | 112 | #define MPOL_MF_DISCONTIG_OK (MPOL_MF_INTERNAL << 0) /* Skip checks for continuous vmas */ |
38e35860 | 113 | #define MPOL_MF_INVERT (MPOL_MF_INTERNAL << 1) /* Invert check for nodemask */ |
dc9aa5b9 | 114 | |
fcc234f8 PE |
115 | static struct kmem_cache *policy_cache; |
116 | static struct kmem_cache *sn_cache; | |
1da177e4 | 117 | |
1da177e4 LT |
118 | /* Highest zone. An specific allocation for a zone below that is not |
119 | policied. */ | |
6267276f | 120 | enum zone_type policy_zone = 0; |
1da177e4 | 121 | |
bea904d5 LS |
122 | /* |
123 | * run-time system-wide default policy => local allocation | |
124 | */ | |
e754d79d | 125 | static struct mempolicy default_policy = { |
1da177e4 | 126 | .refcnt = ATOMIC_INIT(1), /* never free it */ |
7858d7bc | 127 | .mode = MPOL_LOCAL, |
1da177e4 LT |
128 | }; |
129 | ||
5606e387 MG |
130 | static struct mempolicy preferred_node_policy[MAX_NUMNODES]; |
131 | ||
b2ca916c DW |
132 | /** |
133 | * numa_map_to_online_node - Find closest online node | |
f6e92f40 | 134 | * @node: Node id to start the search |
b2ca916c DW |
135 | * |
136 | * Lookup the next closest node by distance if @nid is not online. | |
137 | */ | |
138 | int numa_map_to_online_node(int node) | |
139 | { | |
4fcbe96e | 140 | int min_dist = INT_MAX, dist, n, min_node; |
b2ca916c | 141 | |
4fcbe96e DW |
142 | if (node == NUMA_NO_NODE || node_online(node)) |
143 | return node; | |
b2ca916c DW |
144 | |
145 | min_node = node; | |
4fcbe96e DW |
146 | for_each_online_node(n) { |
147 | dist = node_distance(node, n); | |
148 | if (dist < min_dist) { | |
149 | min_dist = dist; | |
150 | min_node = n; | |
b2ca916c DW |
151 | } |
152 | } | |
153 | ||
154 | return min_node; | |
155 | } | |
156 | EXPORT_SYMBOL_GPL(numa_map_to_online_node); | |
157 | ||
74d2c3a0 | 158 | struct mempolicy *get_task_policy(struct task_struct *p) |
5606e387 MG |
159 | { |
160 | struct mempolicy *pol = p->mempolicy; | |
f15ca78e | 161 | int node; |
5606e387 | 162 | |
f15ca78e ON |
163 | if (pol) |
164 | return pol; | |
5606e387 | 165 | |
f15ca78e ON |
166 | node = numa_node_id(); |
167 | if (node != NUMA_NO_NODE) { | |
168 | pol = &preferred_node_policy[node]; | |
169 | /* preferred_node_policy is not initialised early in boot */ | |
170 | if (pol->mode) | |
171 | return pol; | |
5606e387 MG |
172 | } |
173 | ||
f15ca78e | 174 | return &default_policy; |
5606e387 MG |
175 | } |
176 | ||
37012946 DR |
177 | static const struct mempolicy_operations { |
178 | int (*create)(struct mempolicy *pol, const nodemask_t *nodes); | |
213980c0 | 179 | void (*rebind)(struct mempolicy *pol, const nodemask_t *nodes); |
37012946 DR |
180 | } mpol_ops[MPOL_MAX]; |
181 | ||
f5b087b5 DR |
182 | static inline int mpol_store_user_nodemask(const struct mempolicy *pol) |
183 | { | |
6d556294 | 184 | return pol->flags & MPOL_MODE_FLAGS; |
4c50bc01 DR |
185 | } |
186 | ||
187 | static void mpol_relative_nodemask(nodemask_t *ret, const nodemask_t *orig, | |
188 | const nodemask_t *rel) | |
189 | { | |
190 | nodemask_t tmp; | |
191 | nodes_fold(tmp, *orig, nodes_weight(*rel)); | |
192 | nodes_onto(*ret, tmp, *rel); | |
f5b087b5 DR |
193 | } |
194 | ||
be897d48 | 195 | static int mpol_new_nodemask(struct mempolicy *pol, const nodemask_t *nodes) |
37012946 DR |
196 | { |
197 | if (nodes_empty(*nodes)) | |
198 | return -EINVAL; | |
269fbe72 | 199 | pol->nodes = *nodes; |
37012946 DR |
200 | return 0; |
201 | } | |
202 | ||
203 | static int mpol_new_preferred(struct mempolicy *pol, const nodemask_t *nodes) | |
204 | { | |
7858d7bc FT |
205 | if (nodes_empty(*nodes)) |
206 | return -EINVAL; | |
269fbe72 BW |
207 | |
208 | nodes_clear(pol->nodes); | |
209 | node_set(first_node(*nodes), pol->nodes); | |
37012946 DR |
210 | return 0; |
211 | } | |
212 | ||
58568d2a MX |
213 | /* |
214 | * mpol_set_nodemask is called after mpol_new() to set up the nodemask, if | |
215 | * any, for the new policy. mpol_new() has already validated the nodes | |
7858d7bc | 216 | * parameter with respect to the policy mode and flags. |
58568d2a MX |
217 | * |
218 | * Must be called holding task's alloc_lock to protect task's mems_allowed | |
c1e8d7c6 | 219 | * and mempolicy. May also be called holding the mmap_lock for write. |
58568d2a | 220 | */ |
4bfc4495 KH |
221 | static int mpol_set_nodemask(struct mempolicy *pol, |
222 | const nodemask_t *nodes, struct nodemask_scratch *nsc) | |
58568d2a | 223 | { |
58568d2a MX |
224 | int ret; |
225 | ||
7858d7bc FT |
226 | /* |
227 | * Default (pol==NULL) resp. local memory policies are not a | |
228 | * subject of any remapping. They also do not need any special | |
229 | * constructor. | |
230 | */ | |
231 | if (!pol || pol->mode == MPOL_LOCAL) | |
58568d2a | 232 | return 0; |
7858d7bc | 233 | |
01f13bd6 | 234 | /* Check N_MEMORY */ |
4bfc4495 | 235 | nodes_and(nsc->mask1, |
01f13bd6 | 236 | cpuset_current_mems_allowed, node_states[N_MEMORY]); |
58568d2a MX |
237 | |
238 | VM_BUG_ON(!nodes); | |
4bfc4495 | 239 | |
7858d7bc FT |
240 | if (pol->flags & MPOL_F_RELATIVE_NODES) |
241 | mpol_relative_nodemask(&nsc->mask2, nodes, &nsc->mask1); | |
242 | else | |
243 | nodes_and(nsc->mask2, *nodes, nsc->mask1); | |
58568d2a | 244 | |
7858d7bc FT |
245 | if (mpol_store_user_nodemask(pol)) |
246 | pol->w.user_nodemask = *nodes; | |
4bfc4495 | 247 | else |
7858d7bc FT |
248 | pol->w.cpuset_mems_allowed = cpuset_current_mems_allowed; |
249 | ||
250 | ret = mpol_ops[pol->mode].create(pol, &nsc->mask2); | |
58568d2a MX |
251 | return ret; |
252 | } | |
253 | ||
254 | /* | |
255 | * This function just creates a new policy, does some check and simple | |
256 | * initialization. You must invoke mpol_set_nodemask() to set nodes. | |
257 | */ | |
028fec41 DR |
258 | static struct mempolicy *mpol_new(unsigned short mode, unsigned short flags, |
259 | nodemask_t *nodes) | |
1da177e4 LT |
260 | { |
261 | struct mempolicy *policy; | |
262 | ||
028fec41 | 263 | pr_debug("setting mode %d flags %d nodes[0] %lx\n", |
00ef2d2f | 264 | mode, flags, nodes ? nodes_addr(*nodes)[0] : NUMA_NO_NODE); |
140d5a49 | 265 | |
3e1f0645 DR |
266 | if (mode == MPOL_DEFAULT) { |
267 | if (nodes && !nodes_empty(*nodes)) | |
37012946 | 268 | return ERR_PTR(-EINVAL); |
d3a71033 | 269 | return NULL; |
37012946 | 270 | } |
3e1f0645 DR |
271 | VM_BUG_ON(!nodes); |
272 | ||
273 | /* | |
274 | * MPOL_PREFERRED cannot be used with MPOL_F_STATIC_NODES or | |
275 | * MPOL_F_RELATIVE_NODES if the nodemask is empty (local allocation). | |
276 | * All other modes require a valid pointer to a non-empty nodemask. | |
277 | */ | |
278 | if (mode == MPOL_PREFERRED) { | |
279 | if (nodes_empty(*nodes)) { | |
280 | if (((flags & MPOL_F_STATIC_NODES) || | |
281 | (flags & MPOL_F_RELATIVE_NODES))) | |
282 | return ERR_PTR(-EINVAL); | |
7858d7bc FT |
283 | |
284 | mode = MPOL_LOCAL; | |
3e1f0645 | 285 | } |
479e2802 | 286 | } else if (mode == MPOL_LOCAL) { |
8d303e44 PK |
287 | if (!nodes_empty(*nodes) || |
288 | (flags & MPOL_F_STATIC_NODES) || | |
289 | (flags & MPOL_F_RELATIVE_NODES)) | |
479e2802 | 290 | return ERR_PTR(-EINVAL); |
3e1f0645 DR |
291 | } else if (nodes_empty(*nodes)) |
292 | return ERR_PTR(-EINVAL); | |
1da177e4 LT |
293 | policy = kmem_cache_alloc(policy_cache, GFP_KERNEL); |
294 | if (!policy) | |
295 | return ERR_PTR(-ENOMEM); | |
296 | atomic_set(&policy->refcnt, 1); | |
45c4745a | 297 | policy->mode = mode; |
3e1f0645 | 298 | policy->flags = flags; |
37012946 | 299 | |
1da177e4 | 300 | return policy; |
37012946 DR |
301 | } |
302 | ||
52cd3b07 LS |
303 | /* Slow path of a mpol destructor. */ |
304 | void __mpol_put(struct mempolicy *p) | |
305 | { | |
306 | if (!atomic_dec_and_test(&p->refcnt)) | |
307 | return; | |
52cd3b07 LS |
308 | kmem_cache_free(policy_cache, p); |
309 | } | |
310 | ||
213980c0 | 311 | static void mpol_rebind_default(struct mempolicy *pol, const nodemask_t *nodes) |
37012946 DR |
312 | { |
313 | } | |
314 | ||
213980c0 | 315 | static void mpol_rebind_nodemask(struct mempolicy *pol, const nodemask_t *nodes) |
37012946 DR |
316 | { |
317 | nodemask_t tmp; | |
318 | ||
319 | if (pol->flags & MPOL_F_STATIC_NODES) | |
320 | nodes_and(tmp, pol->w.user_nodemask, *nodes); | |
321 | else if (pol->flags & MPOL_F_RELATIVE_NODES) | |
322 | mpol_relative_nodemask(&tmp, &pol->w.user_nodemask, nodes); | |
323 | else { | |
269fbe72 | 324 | nodes_remap(tmp, pol->nodes, pol->w.cpuset_mems_allowed, |
213980c0 | 325 | *nodes); |
29b190fa | 326 | pol->w.cpuset_mems_allowed = *nodes; |
37012946 | 327 | } |
f5b087b5 | 328 | |
708c1bbc MX |
329 | if (nodes_empty(tmp)) |
330 | tmp = *nodes; | |
331 | ||
269fbe72 | 332 | pol->nodes = tmp; |
37012946 DR |
333 | } |
334 | ||
335 | static void mpol_rebind_preferred(struct mempolicy *pol, | |
213980c0 | 336 | const nodemask_t *nodes) |
37012946 | 337 | { |
7858d7bc | 338 | pol->w.cpuset_mems_allowed = *nodes; |
1da177e4 LT |
339 | } |
340 | ||
708c1bbc MX |
341 | /* |
342 | * mpol_rebind_policy - Migrate a policy to a different set of nodes | |
343 | * | |
c1e8d7c6 | 344 | * Per-vma policies are protected by mmap_lock. Allocations using per-task |
213980c0 VB |
345 | * policies are protected by task->mems_allowed_seq to prevent a premature |
346 | * OOM/allocation failure due to parallel nodemask modification. | |
708c1bbc | 347 | */ |
213980c0 | 348 | static void mpol_rebind_policy(struct mempolicy *pol, const nodemask_t *newmask) |
1d0d2680 | 349 | { |
1d0d2680 DR |
350 | if (!pol) |
351 | return; | |
7858d7bc | 352 | if (!mpol_store_user_nodemask(pol) && |
1d0d2680 DR |
353 | nodes_equal(pol->w.cpuset_mems_allowed, *newmask)) |
354 | return; | |
708c1bbc | 355 | |
213980c0 | 356 | mpol_ops[pol->mode].rebind(pol, newmask); |
1d0d2680 DR |
357 | } |
358 | ||
359 | /* | |
360 | * Wrapper for mpol_rebind_policy() that just requires task | |
361 | * pointer, and updates task mempolicy. | |
58568d2a MX |
362 | * |
363 | * Called with task's alloc_lock held. | |
1d0d2680 DR |
364 | */ |
365 | ||
213980c0 | 366 | void mpol_rebind_task(struct task_struct *tsk, const nodemask_t *new) |
1d0d2680 | 367 | { |
213980c0 | 368 | mpol_rebind_policy(tsk->mempolicy, new); |
1d0d2680 DR |
369 | } |
370 | ||
371 | /* | |
372 | * Rebind each vma in mm to new nodemask. | |
373 | * | |
c1e8d7c6 | 374 | * Call holding a reference to mm. Takes mm->mmap_lock during call. |
1d0d2680 DR |
375 | */ |
376 | ||
377 | void mpol_rebind_mm(struct mm_struct *mm, nodemask_t *new) | |
378 | { | |
379 | struct vm_area_struct *vma; | |
380 | ||
d8ed45c5 | 381 | mmap_write_lock(mm); |
1d0d2680 | 382 | for (vma = mm->mmap; vma; vma = vma->vm_next) |
213980c0 | 383 | mpol_rebind_policy(vma->vm_policy, new); |
d8ed45c5 | 384 | mmap_write_unlock(mm); |
1d0d2680 DR |
385 | } |
386 | ||
37012946 DR |
387 | static const struct mempolicy_operations mpol_ops[MPOL_MAX] = { |
388 | [MPOL_DEFAULT] = { | |
389 | .rebind = mpol_rebind_default, | |
390 | }, | |
391 | [MPOL_INTERLEAVE] = { | |
be897d48 | 392 | .create = mpol_new_nodemask, |
37012946 DR |
393 | .rebind = mpol_rebind_nodemask, |
394 | }, | |
395 | [MPOL_PREFERRED] = { | |
396 | .create = mpol_new_preferred, | |
397 | .rebind = mpol_rebind_preferred, | |
398 | }, | |
399 | [MPOL_BIND] = { | |
be897d48 | 400 | .create = mpol_new_nodemask, |
37012946 DR |
401 | .rebind = mpol_rebind_nodemask, |
402 | }, | |
7858d7bc FT |
403 | [MPOL_LOCAL] = { |
404 | .rebind = mpol_rebind_default, | |
405 | }, | |
b27abacc | 406 | [MPOL_PREFERRED_MANY] = { |
be897d48 | 407 | .create = mpol_new_nodemask, |
b27abacc DH |
408 | .rebind = mpol_rebind_preferred, |
409 | }, | |
37012946 DR |
410 | }; |
411 | ||
a53190a4 | 412 | static int migrate_page_add(struct page *page, struct list_head *pagelist, |
fc301289 | 413 | unsigned long flags); |
1a75a6c8 | 414 | |
6f4576e3 NH |
415 | struct queue_pages { |
416 | struct list_head *pagelist; | |
417 | unsigned long flags; | |
418 | nodemask_t *nmask; | |
f18da660 LX |
419 | unsigned long start; |
420 | unsigned long end; | |
421 | struct vm_area_struct *first; | |
6f4576e3 NH |
422 | }; |
423 | ||
88aaa2a1 NH |
424 | /* |
425 | * Check if the page's nid is in qp->nmask. | |
426 | * | |
427 | * If MPOL_MF_INVERT is set in qp->flags, check if the nid is | |
428 | * in the invert of qp->nmask. | |
429 | */ | |
430 | static inline bool queue_pages_required(struct page *page, | |
431 | struct queue_pages *qp) | |
432 | { | |
433 | int nid = page_to_nid(page); | |
434 | unsigned long flags = qp->flags; | |
435 | ||
436 | return node_isset(nid, *qp->nmask) == !(flags & MPOL_MF_INVERT); | |
437 | } | |
438 | ||
a7f40cfe | 439 | /* |
d8835445 | 440 | * queue_pages_pmd() has four possible return values: |
e5947d23 YS |
441 | * 0 - pages are placed on the right node or queued successfully, or |
442 | * special page is met, i.e. huge zero page. | |
d8835445 YS |
443 | * 1 - there is unmovable page, and MPOL_MF_MOVE* & MPOL_MF_STRICT were |
444 | * specified. | |
445 | * 2 - THP was split. | |
446 | * -EIO - is migration entry or only MPOL_MF_STRICT was specified and an | |
447 | * existing page was already on a node that does not follow the | |
448 | * policy. | |
a7f40cfe | 449 | */ |
c8633798 NH |
450 | static int queue_pages_pmd(pmd_t *pmd, spinlock_t *ptl, unsigned long addr, |
451 | unsigned long end, struct mm_walk *walk) | |
959a7e13 | 452 | __releases(ptl) |
c8633798 NH |
453 | { |
454 | int ret = 0; | |
455 | struct page *page; | |
456 | struct queue_pages *qp = walk->private; | |
457 | unsigned long flags; | |
458 | ||
459 | if (unlikely(is_pmd_migration_entry(*pmd))) { | |
a7f40cfe | 460 | ret = -EIO; |
c8633798 NH |
461 | goto unlock; |
462 | } | |
463 | page = pmd_page(*pmd); | |
464 | if (is_huge_zero_page(page)) { | |
465 | spin_unlock(ptl); | |
e5947d23 | 466 | walk->action = ACTION_CONTINUE; |
c8633798 NH |
467 | goto out; |
468 | } | |
d8835445 | 469 | if (!queue_pages_required(page, qp)) |
c8633798 | 470 | goto unlock; |
c8633798 | 471 | |
c8633798 NH |
472 | flags = qp->flags; |
473 | /* go to thp migration */ | |
a7f40cfe | 474 | if (flags & (MPOL_MF_MOVE | MPOL_MF_MOVE_ALL)) { |
a53190a4 YS |
475 | if (!vma_migratable(walk->vma) || |
476 | migrate_page_add(page, qp->pagelist, flags)) { | |
d8835445 | 477 | ret = 1; |
a7f40cfe YS |
478 | goto unlock; |
479 | } | |
a7f40cfe YS |
480 | } else |
481 | ret = -EIO; | |
c8633798 NH |
482 | unlock: |
483 | spin_unlock(ptl); | |
484 | out: | |
485 | return ret; | |
486 | } | |
487 | ||
98094945 NH |
488 | /* |
489 | * Scan through pages checking if pages follow certain conditions, | |
490 | * and move them to the pagelist if they do. | |
d8835445 YS |
491 | * |
492 | * queue_pages_pte_range() has three possible return values: | |
e5947d23 YS |
493 | * 0 - pages are placed on the right node or queued successfully, or |
494 | * special page is met, i.e. zero page. | |
d8835445 YS |
495 | * 1 - there is unmovable page, and MPOL_MF_MOVE* & MPOL_MF_STRICT were |
496 | * specified. | |
497 | * -EIO - only MPOL_MF_STRICT was specified and an existing page was already | |
498 | * on a node that does not follow the policy. | |
98094945 | 499 | */ |
6f4576e3 NH |
500 | static int queue_pages_pte_range(pmd_t *pmd, unsigned long addr, |
501 | unsigned long end, struct mm_walk *walk) | |
1da177e4 | 502 | { |
6f4576e3 NH |
503 | struct vm_area_struct *vma = walk->vma; |
504 | struct page *page; | |
505 | struct queue_pages *qp = walk->private; | |
506 | unsigned long flags = qp->flags; | |
c8633798 | 507 | int ret; |
d8835445 | 508 | bool has_unmovable = false; |
3f088420 | 509 | pte_t *pte, *mapped_pte; |
705e87c0 | 510 | spinlock_t *ptl; |
941150a3 | 511 | |
c8633798 NH |
512 | ptl = pmd_trans_huge_lock(pmd, vma); |
513 | if (ptl) { | |
514 | ret = queue_pages_pmd(pmd, ptl, addr, end, walk); | |
d8835445 | 515 | if (ret != 2) |
a7f40cfe | 516 | return ret; |
248db92d | 517 | } |
d8835445 | 518 | /* THP was split, fall through to pte walk */ |
91612e0d | 519 | |
337d9abf NH |
520 | if (pmd_trans_unstable(pmd)) |
521 | return 0; | |
94723aaf | 522 | |
3f088420 | 523 | mapped_pte = pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl); |
6f4576e3 | 524 | for (; addr != end; pte++, addr += PAGE_SIZE) { |
91612e0d | 525 | if (!pte_present(*pte)) |
1da177e4 | 526 | continue; |
6aab341e LT |
527 | page = vm_normal_page(vma, addr, *pte); |
528 | if (!page) | |
1da177e4 | 529 | continue; |
053837fc | 530 | /* |
62b61f61 HD |
531 | * vm_normal_page() filters out zero pages, but there might |
532 | * still be PageReserved pages to skip, perhaps in a VDSO. | |
053837fc | 533 | */ |
b79bc0a0 | 534 | if (PageReserved(page)) |
f4598c8b | 535 | continue; |
88aaa2a1 | 536 | if (!queue_pages_required(page, qp)) |
38e35860 | 537 | continue; |
a7f40cfe | 538 | if (flags & (MPOL_MF_MOVE | MPOL_MF_MOVE_ALL)) { |
d8835445 YS |
539 | /* MPOL_MF_STRICT must be specified if we get here */ |
540 | if (!vma_migratable(vma)) { | |
541 | has_unmovable = true; | |
a7f40cfe | 542 | break; |
d8835445 | 543 | } |
a53190a4 YS |
544 | |
545 | /* | |
546 | * Do not abort immediately since there may be | |
547 | * temporary off LRU pages in the range. Still | |
548 | * need migrate other LRU pages. | |
549 | */ | |
550 | if (migrate_page_add(page, qp->pagelist, flags)) | |
551 | has_unmovable = true; | |
a7f40cfe YS |
552 | } else |
553 | break; | |
6f4576e3 | 554 | } |
3f088420 | 555 | pte_unmap_unlock(mapped_pte, ptl); |
6f4576e3 | 556 | cond_resched(); |
d8835445 YS |
557 | |
558 | if (has_unmovable) | |
559 | return 1; | |
560 | ||
a7f40cfe | 561 | return addr != end ? -EIO : 0; |
91612e0d HD |
562 | } |
563 | ||
6f4576e3 NH |
564 | static int queue_pages_hugetlb(pte_t *pte, unsigned long hmask, |
565 | unsigned long addr, unsigned long end, | |
566 | struct mm_walk *walk) | |
e2d8cf40 | 567 | { |
dcf17635 | 568 | int ret = 0; |
e2d8cf40 | 569 | #ifdef CONFIG_HUGETLB_PAGE |
6f4576e3 | 570 | struct queue_pages *qp = walk->private; |
dcf17635 | 571 | unsigned long flags = (qp->flags & MPOL_MF_VALID); |
e2d8cf40 | 572 | struct page *page; |
cb900f41 | 573 | spinlock_t *ptl; |
d4c54919 | 574 | pte_t entry; |
e2d8cf40 | 575 | |
6f4576e3 NH |
576 | ptl = huge_pte_lock(hstate_vma(walk->vma), walk->mm, pte); |
577 | entry = huge_ptep_get(pte); | |
d4c54919 NH |
578 | if (!pte_present(entry)) |
579 | goto unlock; | |
580 | page = pte_page(entry); | |
88aaa2a1 | 581 | if (!queue_pages_required(page, qp)) |
e2d8cf40 | 582 | goto unlock; |
dcf17635 LX |
583 | |
584 | if (flags == MPOL_MF_STRICT) { | |
585 | /* | |
586 | * STRICT alone means only detecting misplaced page and no | |
587 | * need to further check other vma. | |
588 | */ | |
589 | ret = -EIO; | |
590 | goto unlock; | |
591 | } | |
592 | ||
593 | if (!vma_migratable(walk->vma)) { | |
594 | /* | |
595 | * Must be STRICT with MOVE*, otherwise .test_walk() have | |
596 | * stopped walking current vma. | |
597 | * Detecting misplaced page but allow migrating pages which | |
598 | * have been queued. | |
599 | */ | |
600 | ret = 1; | |
601 | goto unlock; | |
602 | } | |
603 | ||
e2d8cf40 NH |
604 | /* With MPOL_MF_MOVE, we migrate only unshared hugepage. */ |
605 | if (flags & (MPOL_MF_MOVE_ALL) || | |
dcf17635 LX |
606 | (flags & MPOL_MF_MOVE && page_mapcount(page) == 1)) { |
607 | if (!isolate_huge_page(page, qp->pagelist) && | |
608 | (flags & MPOL_MF_STRICT)) | |
609 | /* | |
610 | * Failed to isolate page but allow migrating pages | |
611 | * which have been queued. | |
612 | */ | |
613 | ret = 1; | |
614 | } | |
e2d8cf40 | 615 | unlock: |
cb900f41 | 616 | spin_unlock(ptl); |
e2d8cf40 NH |
617 | #else |
618 | BUG(); | |
619 | #endif | |
dcf17635 | 620 | return ret; |
1da177e4 LT |
621 | } |
622 | ||
5877231f | 623 | #ifdef CONFIG_NUMA_BALANCING |
b24f53a0 | 624 | /* |
4b10e7d5 MG |
625 | * This is used to mark a range of virtual addresses to be inaccessible. |
626 | * These are later cleared by a NUMA hinting fault. Depending on these | |
627 | * faults, pages may be migrated for better NUMA placement. | |
628 | * | |
629 | * This is assuming that NUMA faults are handled using PROT_NONE. If | |
630 | * an architecture makes a different choice, it will need further | |
631 | * changes to the core. | |
b24f53a0 | 632 | */ |
4b10e7d5 MG |
633 | unsigned long change_prot_numa(struct vm_area_struct *vma, |
634 | unsigned long addr, unsigned long end) | |
b24f53a0 | 635 | { |
4b10e7d5 | 636 | int nr_updated; |
b24f53a0 | 637 | |
58705444 | 638 | nr_updated = change_protection(vma, addr, end, PAGE_NONE, MM_CP_PROT_NUMA); |
03c5a6e1 MG |
639 | if (nr_updated) |
640 | count_vm_numa_events(NUMA_PTE_UPDATES, nr_updated); | |
b24f53a0 | 641 | |
4b10e7d5 | 642 | return nr_updated; |
b24f53a0 LS |
643 | } |
644 | #else | |
645 | static unsigned long change_prot_numa(struct vm_area_struct *vma, | |
646 | unsigned long addr, unsigned long end) | |
647 | { | |
648 | return 0; | |
649 | } | |
5877231f | 650 | #endif /* CONFIG_NUMA_BALANCING */ |
b24f53a0 | 651 | |
6f4576e3 NH |
652 | static int queue_pages_test_walk(unsigned long start, unsigned long end, |
653 | struct mm_walk *walk) | |
654 | { | |
655 | struct vm_area_struct *vma = walk->vma; | |
656 | struct queue_pages *qp = walk->private; | |
657 | unsigned long endvma = vma->vm_end; | |
658 | unsigned long flags = qp->flags; | |
659 | ||
a18b3ac2 | 660 | /* range check first */ |
ce33135c | 661 | VM_BUG_ON_VMA(!range_in_vma(vma, start, end), vma); |
f18da660 LX |
662 | |
663 | if (!qp->first) { | |
664 | qp->first = vma; | |
665 | if (!(flags & MPOL_MF_DISCONTIG_OK) && | |
666 | (qp->start < vma->vm_start)) | |
667 | /* hole at head side of range */ | |
a18b3ac2 LX |
668 | return -EFAULT; |
669 | } | |
f18da660 LX |
670 | if (!(flags & MPOL_MF_DISCONTIG_OK) && |
671 | ((vma->vm_end < qp->end) && | |
672 | (!vma->vm_next || vma->vm_end < vma->vm_next->vm_start))) | |
673 | /* hole at middle or tail of range */ | |
674 | return -EFAULT; | |
a18b3ac2 | 675 | |
a7f40cfe YS |
676 | /* |
677 | * Need check MPOL_MF_STRICT to return -EIO if possible | |
678 | * regardless of vma_migratable | |
679 | */ | |
680 | if (!vma_migratable(vma) && | |
681 | !(flags & MPOL_MF_STRICT)) | |
48684a65 NH |
682 | return 1; |
683 | ||
6f4576e3 NH |
684 | if (endvma > end) |
685 | endvma = end; | |
6f4576e3 | 686 | |
6f4576e3 NH |
687 | if (flags & MPOL_MF_LAZY) { |
688 | /* Similar to task_numa_work, skip inaccessible VMAs */ | |
3122e80e | 689 | if (!is_vm_hugetlb_page(vma) && vma_is_accessible(vma) && |
4355c018 | 690 | !(vma->vm_flags & VM_MIXEDMAP)) |
6f4576e3 NH |
691 | change_prot_numa(vma, start, endvma); |
692 | return 1; | |
693 | } | |
694 | ||
77bf45e7 | 695 | /* queue pages from current vma */ |
a7f40cfe | 696 | if (flags & MPOL_MF_VALID) |
6f4576e3 NH |
697 | return 0; |
698 | return 1; | |
699 | } | |
700 | ||
7b86ac33 CH |
701 | static const struct mm_walk_ops queue_pages_walk_ops = { |
702 | .hugetlb_entry = queue_pages_hugetlb, | |
703 | .pmd_entry = queue_pages_pte_range, | |
704 | .test_walk = queue_pages_test_walk, | |
705 | }; | |
706 | ||
dc9aa5b9 | 707 | /* |
98094945 NH |
708 | * Walk through page tables and collect pages to be migrated. |
709 | * | |
710 | * If pages found in a given range are on a set of nodes (determined by | |
711 | * @nodes and @flags,) it's isolated and queued to the pagelist which is | |
d8835445 YS |
712 | * passed via @private. |
713 | * | |
714 | * queue_pages_range() has three possible return values: | |
715 | * 1 - there is unmovable page, but MPOL_MF_MOVE* & MPOL_MF_STRICT were | |
716 | * specified. | |
717 | * 0 - queue pages successfully or no misplaced page. | |
a85dfc30 YS |
718 | * errno - i.e. misplaced pages with MPOL_MF_STRICT specified (-EIO) or |
719 | * memory range specified by nodemask and maxnode points outside | |
720 | * your accessible address space (-EFAULT) | |
dc9aa5b9 | 721 | */ |
d05f0cdc | 722 | static int |
98094945 | 723 | queue_pages_range(struct mm_struct *mm, unsigned long start, unsigned long end, |
6f4576e3 NH |
724 | nodemask_t *nodes, unsigned long flags, |
725 | struct list_head *pagelist) | |
1da177e4 | 726 | { |
f18da660 | 727 | int err; |
6f4576e3 NH |
728 | struct queue_pages qp = { |
729 | .pagelist = pagelist, | |
730 | .flags = flags, | |
731 | .nmask = nodes, | |
f18da660 LX |
732 | .start = start, |
733 | .end = end, | |
734 | .first = NULL, | |
6f4576e3 | 735 | }; |
6f4576e3 | 736 | |
f18da660 LX |
737 | err = walk_page_range(mm, start, end, &queue_pages_walk_ops, &qp); |
738 | ||
739 | if (!qp.first) | |
740 | /* whole range in hole */ | |
741 | err = -EFAULT; | |
742 | ||
743 | return err; | |
1da177e4 LT |
744 | } |
745 | ||
869833f2 KM |
746 | /* |
747 | * Apply policy to a single VMA | |
c1e8d7c6 | 748 | * This must be called with the mmap_lock held for writing. |
869833f2 KM |
749 | */ |
750 | static int vma_replace_policy(struct vm_area_struct *vma, | |
751 | struct mempolicy *pol) | |
8d34694c | 752 | { |
869833f2 KM |
753 | int err; |
754 | struct mempolicy *old; | |
755 | struct mempolicy *new; | |
8d34694c KM |
756 | |
757 | pr_debug("vma %lx-%lx/%lx vm_ops %p vm_file %p set_policy %p\n", | |
758 | vma->vm_start, vma->vm_end, vma->vm_pgoff, | |
759 | vma->vm_ops, vma->vm_file, | |
760 | vma->vm_ops ? vma->vm_ops->set_policy : NULL); | |
761 | ||
869833f2 KM |
762 | new = mpol_dup(pol); |
763 | if (IS_ERR(new)) | |
764 | return PTR_ERR(new); | |
765 | ||
766 | if (vma->vm_ops && vma->vm_ops->set_policy) { | |
8d34694c | 767 | err = vma->vm_ops->set_policy(vma, new); |
869833f2 KM |
768 | if (err) |
769 | goto err_out; | |
8d34694c | 770 | } |
869833f2 KM |
771 | |
772 | old = vma->vm_policy; | |
c1e8d7c6 | 773 | vma->vm_policy = new; /* protected by mmap_lock */ |
869833f2 KM |
774 | mpol_put(old); |
775 | ||
776 | return 0; | |
777 | err_out: | |
778 | mpol_put(new); | |
8d34694c KM |
779 | return err; |
780 | } | |
781 | ||
1da177e4 | 782 | /* Step 2: apply policy to a range and do splits. */ |
9d8cebd4 KM |
783 | static int mbind_range(struct mm_struct *mm, unsigned long start, |
784 | unsigned long end, struct mempolicy *new_pol) | |
1da177e4 LT |
785 | { |
786 | struct vm_area_struct *next; | |
9d8cebd4 KM |
787 | struct vm_area_struct *prev; |
788 | struct vm_area_struct *vma; | |
789 | int err = 0; | |
e26a5114 | 790 | pgoff_t pgoff; |
9d8cebd4 KM |
791 | unsigned long vmstart; |
792 | unsigned long vmend; | |
1da177e4 | 793 | |
097d5910 | 794 | vma = find_vma(mm, start); |
f18da660 | 795 | VM_BUG_ON(!vma); |
9d8cebd4 | 796 | |
097d5910 | 797 | prev = vma->vm_prev; |
e26a5114 KM |
798 | if (start > vma->vm_start) |
799 | prev = vma; | |
800 | ||
9d8cebd4 | 801 | for (; vma && vma->vm_start < end; prev = vma, vma = next) { |
1da177e4 | 802 | next = vma->vm_next; |
9d8cebd4 KM |
803 | vmstart = max(start, vma->vm_start); |
804 | vmend = min(end, vma->vm_end); | |
805 | ||
e26a5114 KM |
806 | if (mpol_equal(vma_policy(vma), new_pol)) |
807 | continue; | |
808 | ||
809 | pgoff = vma->vm_pgoff + | |
810 | ((vmstart - vma->vm_start) >> PAGE_SHIFT); | |
9d8cebd4 | 811 | prev = vma_merge(mm, prev, vmstart, vmend, vma->vm_flags, |
19a809af AA |
812 | vma->anon_vma, vma->vm_file, pgoff, |
813 | new_pol, vma->vm_userfaultfd_ctx); | |
9d8cebd4 KM |
814 | if (prev) { |
815 | vma = prev; | |
816 | next = vma->vm_next; | |
3964acd0 ON |
817 | if (mpol_equal(vma_policy(vma), new_pol)) |
818 | continue; | |
819 | /* vma_merge() joined vma && vma->next, case 8 */ | |
820 | goto replace; | |
9d8cebd4 KM |
821 | } |
822 | if (vma->vm_start != vmstart) { | |
823 | err = split_vma(vma->vm_mm, vma, vmstart, 1); | |
824 | if (err) | |
825 | goto out; | |
826 | } | |
827 | if (vma->vm_end != vmend) { | |
828 | err = split_vma(vma->vm_mm, vma, vmend, 0); | |
829 | if (err) | |
830 | goto out; | |
831 | } | |
3964acd0 | 832 | replace: |
869833f2 | 833 | err = vma_replace_policy(vma, new_pol); |
8d34694c KM |
834 | if (err) |
835 | goto out; | |
1da177e4 | 836 | } |
9d8cebd4 KM |
837 | |
838 | out: | |
1da177e4 LT |
839 | return err; |
840 | } | |
841 | ||
1da177e4 | 842 | /* Set the process memory policy */ |
028fec41 DR |
843 | static long do_set_mempolicy(unsigned short mode, unsigned short flags, |
844 | nodemask_t *nodes) | |
1da177e4 | 845 | { |
58568d2a | 846 | struct mempolicy *new, *old; |
4bfc4495 | 847 | NODEMASK_SCRATCH(scratch); |
58568d2a | 848 | int ret; |
1da177e4 | 849 | |
4bfc4495 KH |
850 | if (!scratch) |
851 | return -ENOMEM; | |
f4e53d91 | 852 | |
4bfc4495 KH |
853 | new = mpol_new(mode, flags, nodes); |
854 | if (IS_ERR(new)) { | |
855 | ret = PTR_ERR(new); | |
856 | goto out; | |
857 | } | |
2c7c3a7d | 858 | |
bda420b9 HY |
859 | if (flags & MPOL_F_NUMA_BALANCING) { |
860 | if (new && new->mode == MPOL_BIND) { | |
861 | new->flags |= (MPOL_F_MOF | MPOL_F_MORON); | |
862 | } else { | |
863 | ret = -EINVAL; | |
864 | mpol_put(new); | |
865 | goto out; | |
866 | } | |
867 | } | |
868 | ||
4bfc4495 | 869 | ret = mpol_set_nodemask(new, nodes, scratch); |
58568d2a | 870 | if (ret) { |
58568d2a | 871 | mpol_put(new); |
4bfc4495 | 872 | goto out; |
58568d2a | 873 | } |
78b132e9 | 874 | task_lock(current); |
58568d2a | 875 | old = current->mempolicy; |
1da177e4 | 876 | current->mempolicy = new; |
45816682 VB |
877 | if (new && new->mode == MPOL_INTERLEAVE) |
878 | current->il_prev = MAX_NUMNODES-1; | |
58568d2a | 879 | task_unlock(current); |
58568d2a | 880 | mpol_put(old); |
4bfc4495 KH |
881 | ret = 0; |
882 | out: | |
883 | NODEMASK_SCRATCH_FREE(scratch); | |
884 | return ret; | |
1da177e4 LT |
885 | } |
886 | ||
bea904d5 LS |
887 | /* |
888 | * Return nodemask for policy for get_mempolicy() query | |
58568d2a MX |
889 | * |
890 | * Called with task's alloc_lock held | |
bea904d5 LS |
891 | */ |
892 | static void get_policy_nodemask(struct mempolicy *p, nodemask_t *nodes) | |
1da177e4 | 893 | { |
dfcd3c0d | 894 | nodes_clear(*nodes); |
bea904d5 LS |
895 | if (p == &default_policy) |
896 | return; | |
897 | ||
45c4745a | 898 | switch (p->mode) { |
19770b32 | 899 | case MPOL_BIND: |
1da177e4 | 900 | case MPOL_INTERLEAVE: |
269fbe72 | 901 | case MPOL_PREFERRED: |
b27abacc | 902 | case MPOL_PREFERRED_MANY: |
269fbe72 | 903 | *nodes = p->nodes; |
1da177e4 | 904 | break; |
7858d7bc FT |
905 | case MPOL_LOCAL: |
906 | /* return empty node mask for local allocation */ | |
907 | break; | |
1da177e4 LT |
908 | default: |
909 | BUG(); | |
910 | } | |
911 | } | |
912 | ||
3b9aadf7 | 913 | static int lookup_node(struct mm_struct *mm, unsigned long addr) |
1da177e4 | 914 | { |
ba841078 | 915 | struct page *p = NULL; |
1da177e4 LT |
916 | int err; |
917 | ||
3b9aadf7 AA |
918 | int locked = 1; |
919 | err = get_user_pages_locked(addr & PAGE_MASK, 1, 0, &p, &locked); | |
2d3a36a4 | 920 | if (err > 0) { |
1da177e4 LT |
921 | err = page_to_nid(p); |
922 | put_page(p); | |
923 | } | |
3b9aadf7 | 924 | if (locked) |
d8ed45c5 | 925 | mmap_read_unlock(mm); |
1da177e4 LT |
926 | return err; |
927 | } | |
928 | ||
1da177e4 | 929 | /* Retrieve NUMA policy */ |
dbcb0f19 AB |
930 | static long do_get_mempolicy(int *policy, nodemask_t *nmask, |
931 | unsigned long addr, unsigned long flags) | |
1da177e4 | 932 | { |
8bccd85f | 933 | int err; |
1da177e4 LT |
934 | struct mm_struct *mm = current->mm; |
935 | struct vm_area_struct *vma = NULL; | |
3b9aadf7 | 936 | struct mempolicy *pol = current->mempolicy, *pol_refcount = NULL; |
1da177e4 | 937 | |
754af6f5 LS |
938 | if (flags & |
939 | ~(unsigned long)(MPOL_F_NODE|MPOL_F_ADDR|MPOL_F_MEMS_ALLOWED)) | |
1da177e4 | 940 | return -EINVAL; |
754af6f5 LS |
941 | |
942 | if (flags & MPOL_F_MEMS_ALLOWED) { | |
943 | if (flags & (MPOL_F_NODE|MPOL_F_ADDR)) | |
944 | return -EINVAL; | |
945 | *policy = 0; /* just so it's initialized */ | |
58568d2a | 946 | task_lock(current); |
754af6f5 | 947 | *nmask = cpuset_current_mems_allowed; |
58568d2a | 948 | task_unlock(current); |
754af6f5 LS |
949 | return 0; |
950 | } | |
951 | ||
1da177e4 | 952 | if (flags & MPOL_F_ADDR) { |
bea904d5 LS |
953 | /* |
954 | * Do NOT fall back to task policy if the | |
955 | * vma/shared policy at addr is NULL. We | |
956 | * want to return MPOL_DEFAULT in this case. | |
957 | */ | |
d8ed45c5 | 958 | mmap_read_lock(mm); |
33e3575c | 959 | vma = vma_lookup(mm, addr); |
1da177e4 | 960 | if (!vma) { |
d8ed45c5 | 961 | mmap_read_unlock(mm); |
1da177e4 LT |
962 | return -EFAULT; |
963 | } | |
964 | if (vma->vm_ops && vma->vm_ops->get_policy) | |
965 | pol = vma->vm_ops->get_policy(vma, addr); | |
966 | else | |
967 | pol = vma->vm_policy; | |
968 | } else if (addr) | |
969 | return -EINVAL; | |
970 | ||
971 | if (!pol) | |
bea904d5 | 972 | pol = &default_policy; /* indicates default behavior */ |
1da177e4 LT |
973 | |
974 | if (flags & MPOL_F_NODE) { | |
975 | if (flags & MPOL_F_ADDR) { | |
3b9aadf7 AA |
976 | /* |
977 | * Take a refcount on the mpol, lookup_node() | |
baf2f90b | 978 | * will drop the mmap_lock, so after calling |
3b9aadf7 AA |
979 | * lookup_node() only "pol" remains valid, "vma" |
980 | * is stale. | |
981 | */ | |
982 | pol_refcount = pol; | |
983 | vma = NULL; | |
984 | mpol_get(pol); | |
985 | err = lookup_node(mm, addr); | |
1da177e4 LT |
986 | if (err < 0) |
987 | goto out; | |
8bccd85f | 988 | *policy = err; |
1da177e4 | 989 | } else if (pol == current->mempolicy && |
45c4745a | 990 | pol->mode == MPOL_INTERLEAVE) { |
269fbe72 | 991 | *policy = next_node_in(current->il_prev, pol->nodes); |
1da177e4 LT |
992 | } else { |
993 | err = -EINVAL; | |
994 | goto out; | |
995 | } | |
bea904d5 LS |
996 | } else { |
997 | *policy = pol == &default_policy ? MPOL_DEFAULT : | |
998 | pol->mode; | |
d79df630 DR |
999 | /* |
1000 | * Internal mempolicy flags must be masked off before exposing | |
1001 | * the policy to userspace. | |
1002 | */ | |
1003 | *policy |= (pol->flags & MPOL_MODE_FLAGS); | |
bea904d5 | 1004 | } |
1da177e4 | 1005 | |
1da177e4 | 1006 | err = 0; |
58568d2a | 1007 | if (nmask) { |
c6b6ef8b LS |
1008 | if (mpol_store_user_nodemask(pol)) { |
1009 | *nmask = pol->w.user_nodemask; | |
1010 | } else { | |
1011 | task_lock(current); | |
1012 | get_policy_nodemask(pol, nmask); | |
1013 | task_unlock(current); | |
1014 | } | |
58568d2a | 1015 | } |
1da177e4 LT |
1016 | |
1017 | out: | |
52cd3b07 | 1018 | mpol_cond_put(pol); |
1da177e4 | 1019 | if (vma) |
d8ed45c5 | 1020 | mmap_read_unlock(mm); |
3b9aadf7 AA |
1021 | if (pol_refcount) |
1022 | mpol_put(pol_refcount); | |
1da177e4 LT |
1023 | return err; |
1024 | } | |
1025 | ||
b20a3503 | 1026 | #ifdef CONFIG_MIGRATION |
6ce3c4c0 | 1027 | /* |
c8633798 | 1028 | * page migration, thp tail pages can be passed. |
6ce3c4c0 | 1029 | */ |
a53190a4 | 1030 | static int migrate_page_add(struct page *page, struct list_head *pagelist, |
fc301289 | 1031 | unsigned long flags) |
6ce3c4c0 | 1032 | { |
c8633798 | 1033 | struct page *head = compound_head(page); |
6ce3c4c0 | 1034 | /* |
fc301289 | 1035 | * Avoid migrating a page that is shared with others. |
6ce3c4c0 | 1036 | */ |
c8633798 NH |
1037 | if ((flags & MPOL_MF_MOVE_ALL) || page_mapcount(head) == 1) { |
1038 | if (!isolate_lru_page(head)) { | |
1039 | list_add_tail(&head->lru, pagelist); | |
1040 | mod_node_page_state(page_pgdat(head), | |
9de4f22a | 1041 | NR_ISOLATED_ANON + page_is_file_lru(head), |
6c357848 | 1042 | thp_nr_pages(head)); |
a53190a4 YS |
1043 | } else if (flags & MPOL_MF_STRICT) { |
1044 | /* | |
1045 | * Non-movable page may reach here. And, there may be | |
1046 | * temporary off LRU pages or non-LRU movable pages. | |
1047 | * Treat them as unmovable pages since they can't be | |
1048 | * isolated, so they can't be moved at the moment. It | |
1049 | * should return -EIO for this case too. | |
1050 | */ | |
1051 | return -EIO; | |
62695a84 NP |
1052 | } |
1053 | } | |
a53190a4 YS |
1054 | |
1055 | return 0; | |
7e2ab150 | 1056 | } |
6ce3c4c0 | 1057 | |
7e2ab150 CL |
1058 | /* |
1059 | * Migrate pages from one node to a target node. | |
1060 | * Returns error or the number of pages not migrated. | |
1061 | */ | |
dbcb0f19 AB |
1062 | static int migrate_to_node(struct mm_struct *mm, int source, int dest, |
1063 | int flags) | |
7e2ab150 CL |
1064 | { |
1065 | nodemask_t nmask; | |
1066 | LIST_HEAD(pagelist); | |
1067 | int err = 0; | |
a0976311 JK |
1068 | struct migration_target_control mtc = { |
1069 | .nid = dest, | |
1070 | .gfp_mask = GFP_HIGHUSER_MOVABLE | __GFP_THISNODE, | |
1071 | }; | |
7e2ab150 CL |
1072 | |
1073 | nodes_clear(nmask); | |
1074 | node_set(source, nmask); | |
6ce3c4c0 | 1075 | |
08270807 MK |
1076 | /* |
1077 | * This does not "check" the range but isolates all pages that | |
1078 | * need migration. Between passing in the full user address | |
1079 | * space range and MPOL_MF_DISCONTIG_OK, this call can not fail. | |
1080 | */ | |
1081 | VM_BUG_ON(!(flags & (MPOL_MF_MOVE | MPOL_MF_MOVE_ALL))); | |
98094945 | 1082 | queue_pages_range(mm, mm->mmap->vm_start, mm->task_size, &nmask, |
7e2ab150 CL |
1083 | flags | MPOL_MF_DISCONTIG_OK, &pagelist); |
1084 | ||
cf608ac1 | 1085 | if (!list_empty(&pagelist)) { |
a0976311 | 1086 | err = migrate_pages(&pagelist, alloc_migration_target, NULL, |
5ac95884 | 1087 | (unsigned long)&mtc, MIGRATE_SYNC, MR_SYSCALL, NULL); |
cf608ac1 | 1088 | if (err) |
e2d8cf40 | 1089 | putback_movable_pages(&pagelist); |
cf608ac1 | 1090 | } |
95a402c3 | 1091 | |
7e2ab150 | 1092 | return err; |
6ce3c4c0 CL |
1093 | } |
1094 | ||
39743889 | 1095 | /* |
7e2ab150 CL |
1096 | * Move pages between the two nodesets so as to preserve the physical |
1097 | * layout as much as possible. | |
39743889 CL |
1098 | * |
1099 | * Returns the number of page that could not be moved. | |
1100 | */ | |
0ce72d4f AM |
1101 | int do_migrate_pages(struct mm_struct *mm, const nodemask_t *from, |
1102 | const nodemask_t *to, int flags) | |
39743889 | 1103 | { |
7e2ab150 | 1104 | int busy = 0; |
f555befd | 1105 | int err = 0; |
7e2ab150 | 1106 | nodemask_t tmp; |
39743889 | 1107 | |
361a2a22 | 1108 | lru_cache_disable(); |
0aedadf9 | 1109 | |
d8ed45c5 | 1110 | mmap_read_lock(mm); |
39743889 | 1111 | |
da0aa138 KM |
1112 | /* |
1113 | * Find a 'source' bit set in 'tmp' whose corresponding 'dest' | |
1114 | * bit in 'to' is not also set in 'tmp'. Clear the found 'source' | |
1115 | * bit in 'tmp', and return that <source, dest> pair for migration. | |
1116 | * The pair of nodemasks 'to' and 'from' define the map. | |
1117 | * | |
1118 | * If no pair of bits is found that way, fallback to picking some | |
1119 | * pair of 'source' and 'dest' bits that are not the same. If the | |
1120 | * 'source' and 'dest' bits are the same, this represents a node | |
1121 | * that will be migrating to itself, so no pages need move. | |
1122 | * | |
1123 | * If no bits are left in 'tmp', or if all remaining bits left | |
1124 | * in 'tmp' correspond to the same bit in 'to', return false | |
1125 | * (nothing left to migrate). | |
1126 | * | |
1127 | * This lets us pick a pair of nodes to migrate between, such that | |
1128 | * if possible the dest node is not already occupied by some other | |
1129 | * source node, minimizing the risk of overloading the memory on a | |
1130 | * node that would happen if we migrated incoming memory to a node | |
1131 | * before migrating outgoing memory source that same node. | |
1132 | * | |
1133 | * A single scan of tmp is sufficient. As we go, we remember the | |
1134 | * most recent <s, d> pair that moved (s != d). If we find a pair | |
1135 | * that not only moved, but what's better, moved to an empty slot | |
1136 | * (d is not set in tmp), then we break out then, with that pair. | |
ae0e47f0 | 1137 | * Otherwise when we finish scanning from_tmp, we at least have the |
da0aa138 KM |
1138 | * most recent <s, d> pair that moved. If we get all the way through |
1139 | * the scan of tmp without finding any node that moved, much less | |
1140 | * moved to an empty node, then there is nothing left worth migrating. | |
1141 | */ | |
d4984711 | 1142 | |
0ce72d4f | 1143 | tmp = *from; |
7e2ab150 | 1144 | while (!nodes_empty(tmp)) { |
68d68ff6 | 1145 | int s, d; |
b76ac7e7 | 1146 | int source = NUMA_NO_NODE; |
7e2ab150 CL |
1147 | int dest = 0; |
1148 | ||
1149 | for_each_node_mask(s, tmp) { | |
4a5b18cc LW |
1150 | |
1151 | /* | |
1152 | * do_migrate_pages() tries to maintain the relative | |
1153 | * node relationship of the pages established between | |
1154 | * threads and memory areas. | |
1155 | * | |
1156 | * However if the number of source nodes is not equal to | |
1157 | * the number of destination nodes we can not preserve | |
1158 | * this node relative relationship. In that case, skip | |
1159 | * copying memory from a node that is in the destination | |
1160 | * mask. | |
1161 | * | |
1162 | * Example: [2,3,4] -> [3,4,5] moves everything. | |
1163 | * [0-7] - > [3,4,5] moves only 0,1,2,6,7. | |
1164 | */ | |
1165 | ||
0ce72d4f AM |
1166 | if ((nodes_weight(*from) != nodes_weight(*to)) && |
1167 | (node_isset(s, *to))) | |
4a5b18cc LW |
1168 | continue; |
1169 | ||
0ce72d4f | 1170 | d = node_remap(s, *from, *to); |
7e2ab150 CL |
1171 | if (s == d) |
1172 | continue; | |
1173 | ||
1174 | source = s; /* Node moved. Memorize */ | |
1175 | dest = d; | |
1176 | ||
1177 | /* dest not in remaining from nodes? */ | |
1178 | if (!node_isset(dest, tmp)) | |
1179 | break; | |
1180 | } | |
b76ac7e7 | 1181 | if (source == NUMA_NO_NODE) |
7e2ab150 CL |
1182 | break; |
1183 | ||
1184 | node_clear(source, tmp); | |
1185 | err = migrate_to_node(mm, source, dest, flags); | |
1186 | if (err > 0) | |
1187 | busy += err; | |
1188 | if (err < 0) | |
1189 | break; | |
39743889 | 1190 | } |
d8ed45c5 | 1191 | mmap_read_unlock(mm); |
d479960e | 1192 | |
361a2a22 | 1193 | lru_cache_enable(); |
7e2ab150 CL |
1194 | if (err < 0) |
1195 | return err; | |
1196 | return busy; | |
b20a3503 CL |
1197 | |
1198 | } | |
1199 | ||
3ad33b24 LS |
1200 | /* |
1201 | * Allocate a new page for page migration based on vma policy. | |
d05f0cdc | 1202 | * Start by assuming the page is mapped by the same vma as contains @start. |
3ad33b24 LS |
1203 | * Search forward from there, if not. N.B., this assumes that the |
1204 | * list of pages handed to migrate_pages()--which is how we get here-- | |
1205 | * is in virtual address order. | |
1206 | */ | |
666feb21 | 1207 | static struct page *new_page(struct page *page, unsigned long start) |
95a402c3 | 1208 | { |
d05f0cdc | 1209 | struct vm_area_struct *vma; |
3f649ab7 | 1210 | unsigned long address; |
95a402c3 | 1211 | |
d05f0cdc | 1212 | vma = find_vma(current->mm, start); |
3ad33b24 LS |
1213 | while (vma) { |
1214 | address = page_address_in_vma(page, vma); | |
1215 | if (address != -EFAULT) | |
1216 | break; | |
1217 | vma = vma->vm_next; | |
1218 | } | |
11c731e8 WL |
1219 | |
1220 | if (PageHuge(page)) { | |
389c8178 MH |
1221 | return alloc_huge_page_vma(page_hstate(compound_head(page)), |
1222 | vma, address); | |
94723aaf | 1223 | } else if (PageTransHuge(page)) { |
c8633798 NH |
1224 | struct page *thp; |
1225 | ||
19deb769 DR |
1226 | thp = alloc_hugepage_vma(GFP_TRANSHUGE, vma, address, |
1227 | HPAGE_PMD_ORDER); | |
c8633798 NH |
1228 | if (!thp) |
1229 | return NULL; | |
1230 | prep_transhuge_page(thp); | |
1231 | return thp; | |
11c731e8 | 1232 | } |
0bf598d8 | 1233 | /* |
11c731e8 | 1234 | * if !vma, alloc_page_vma() will use task or system default policy |
0bf598d8 | 1235 | */ |
0f556856 MH |
1236 | return alloc_page_vma(GFP_HIGHUSER_MOVABLE | __GFP_RETRY_MAYFAIL, |
1237 | vma, address); | |
95a402c3 | 1238 | } |
b20a3503 CL |
1239 | #else |
1240 | ||
a53190a4 | 1241 | static int migrate_page_add(struct page *page, struct list_head *pagelist, |
b20a3503 CL |
1242 | unsigned long flags) |
1243 | { | |
a53190a4 | 1244 | return -EIO; |
39743889 CL |
1245 | } |
1246 | ||
0ce72d4f AM |
1247 | int do_migrate_pages(struct mm_struct *mm, const nodemask_t *from, |
1248 | const nodemask_t *to, int flags) | |
b20a3503 CL |
1249 | { |
1250 | return -ENOSYS; | |
1251 | } | |
95a402c3 | 1252 | |
666feb21 | 1253 | static struct page *new_page(struct page *page, unsigned long start) |
95a402c3 CL |
1254 | { |
1255 | return NULL; | |
1256 | } | |
b20a3503 CL |
1257 | #endif |
1258 | ||
dbcb0f19 | 1259 | static long do_mbind(unsigned long start, unsigned long len, |
028fec41 DR |
1260 | unsigned short mode, unsigned short mode_flags, |
1261 | nodemask_t *nmask, unsigned long flags) | |
6ce3c4c0 | 1262 | { |
6ce3c4c0 CL |
1263 | struct mm_struct *mm = current->mm; |
1264 | struct mempolicy *new; | |
1265 | unsigned long end; | |
1266 | int err; | |
d8835445 | 1267 | int ret; |
6ce3c4c0 CL |
1268 | LIST_HEAD(pagelist); |
1269 | ||
b24f53a0 | 1270 | if (flags & ~(unsigned long)MPOL_MF_VALID) |
6ce3c4c0 | 1271 | return -EINVAL; |
74c00241 | 1272 | if ((flags & MPOL_MF_MOVE_ALL) && !capable(CAP_SYS_NICE)) |
6ce3c4c0 CL |
1273 | return -EPERM; |
1274 | ||
1275 | if (start & ~PAGE_MASK) | |
1276 | return -EINVAL; | |
1277 | ||
1278 | if (mode == MPOL_DEFAULT) | |
1279 | flags &= ~MPOL_MF_STRICT; | |
1280 | ||
1281 | len = (len + PAGE_SIZE - 1) & PAGE_MASK; | |
1282 | end = start + len; | |
1283 | ||
1284 | if (end < start) | |
1285 | return -EINVAL; | |
1286 | if (end == start) | |
1287 | return 0; | |
1288 | ||
028fec41 | 1289 | new = mpol_new(mode, mode_flags, nmask); |
6ce3c4c0 CL |
1290 | if (IS_ERR(new)) |
1291 | return PTR_ERR(new); | |
1292 | ||
b24f53a0 LS |
1293 | if (flags & MPOL_MF_LAZY) |
1294 | new->flags |= MPOL_F_MOF; | |
1295 | ||
6ce3c4c0 CL |
1296 | /* |
1297 | * If we are using the default policy then operation | |
1298 | * on discontinuous address spaces is okay after all | |
1299 | */ | |
1300 | if (!new) | |
1301 | flags |= MPOL_MF_DISCONTIG_OK; | |
1302 | ||
028fec41 DR |
1303 | pr_debug("mbind %lx-%lx mode:%d flags:%d nodes:%lx\n", |
1304 | start, start + len, mode, mode_flags, | |
00ef2d2f | 1305 | nmask ? nodes_addr(*nmask)[0] : NUMA_NO_NODE); |
6ce3c4c0 | 1306 | |
0aedadf9 CL |
1307 | if (flags & (MPOL_MF_MOVE | MPOL_MF_MOVE_ALL)) { |
1308 | ||
361a2a22 | 1309 | lru_cache_disable(); |
0aedadf9 | 1310 | } |
4bfc4495 KH |
1311 | { |
1312 | NODEMASK_SCRATCH(scratch); | |
1313 | if (scratch) { | |
d8ed45c5 | 1314 | mmap_write_lock(mm); |
4bfc4495 | 1315 | err = mpol_set_nodemask(new, nmask, scratch); |
4bfc4495 | 1316 | if (err) |
d8ed45c5 | 1317 | mmap_write_unlock(mm); |
4bfc4495 KH |
1318 | } else |
1319 | err = -ENOMEM; | |
1320 | NODEMASK_SCRATCH_FREE(scratch); | |
1321 | } | |
b05ca738 KM |
1322 | if (err) |
1323 | goto mpol_out; | |
1324 | ||
d8835445 | 1325 | ret = queue_pages_range(mm, start, end, nmask, |
6ce3c4c0 | 1326 | flags | MPOL_MF_INVERT, &pagelist); |
d8835445 YS |
1327 | |
1328 | if (ret < 0) { | |
a85dfc30 | 1329 | err = ret; |
d8835445 YS |
1330 | goto up_out; |
1331 | } | |
1332 | ||
1333 | err = mbind_range(mm, start, end, new); | |
7e2ab150 | 1334 | |
b24f53a0 LS |
1335 | if (!err) { |
1336 | int nr_failed = 0; | |
1337 | ||
cf608ac1 | 1338 | if (!list_empty(&pagelist)) { |
b24f53a0 | 1339 | WARN_ON_ONCE(flags & MPOL_MF_LAZY); |
d05f0cdc | 1340 | nr_failed = migrate_pages(&pagelist, new_page, NULL, |
5ac95884 | 1341 | start, MIGRATE_SYNC, MR_MEMPOLICY_MBIND, NULL); |
cf608ac1 | 1342 | if (nr_failed) |
74060e4d | 1343 | putback_movable_pages(&pagelist); |
cf608ac1 | 1344 | } |
6ce3c4c0 | 1345 | |
d8835445 | 1346 | if ((ret > 0) || (nr_failed && (flags & MPOL_MF_STRICT))) |
6ce3c4c0 | 1347 | err = -EIO; |
a85dfc30 | 1348 | } else { |
d8835445 | 1349 | up_out: |
a85dfc30 YS |
1350 | if (!list_empty(&pagelist)) |
1351 | putback_movable_pages(&pagelist); | |
1352 | } | |
1353 | ||
d8ed45c5 | 1354 | mmap_write_unlock(mm); |
d8835445 | 1355 | mpol_out: |
f0be3d32 | 1356 | mpol_put(new); |
d479960e | 1357 | if (flags & (MPOL_MF_MOVE | MPOL_MF_MOVE_ALL)) |
361a2a22 | 1358 | lru_cache_enable(); |
6ce3c4c0 CL |
1359 | return err; |
1360 | } | |
1361 | ||
8bccd85f CL |
1362 | /* |
1363 | * User space interface with variable sized bitmaps for nodelists. | |
1364 | */ | |
e130242d AB |
1365 | static int get_bitmap(unsigned long *mask, const unsigned long __user *nmask, |
1366 | unsigned long maxnode) | |
1367 | { | |
1368 | unsigned long nlongs = BITS_TO_LONGS(maxnode); | |
1369 | int ret; | |
1370 | ||
1371 | if (in_compat_syscall()) | |
1372 | ret = compat_get_bitmap(mask, | |
1373 | (const compat_ulong_t __user *)nmask, | |
1374 | maxnode); | |
1375 | else | |
1376 | ret = copy_from_user(mask, nmask, | |
1377 | nlongs * sizeof(unsigned long)); | |
1378 | ||
1379 | if (ret) | |
1380 | return -EFAULT; | |
1381 | ||
1382 | if (maxnode % BITS_PER_LONG) | |
1383 | mask[nlongs - 1] &= (1UL << (maxnode % BITS_PER_LONG)) - 1; | |
1384 | ||
1385 | return 0; | |
1386 | } | |
8bccd85f CL |
1387 | |
1388 | /* Copy a node mask from user space. */ | |
39743889 | 1389 | static int get_nodes(nodemask_t *nodes, const unsigned long __user *nmask, |
8bccd85f CL |
1390 | unsigned long maxnode) |
1391 | { | |
8bccd85f CL |
1392 | --maxnode; |
1393 | nodes_clear(*nodes); | |
1394 | if (maxnode == 0 || !nmask) | |
1395 | return 0; | |
a9c930ba | 1396 | if (maxnode > PAGE_SIZE*BITS_PER_BYTE) |
636f13c1 | 1397 | return -EINVAL; |
8bccd85f | 1398 | |
56521e7a YX |
1399 | /* |
1400 | * When the user specified more nodes than supported just check | |
e130242d AB |
1401 | * if the non supported part is all zero, one word at a time, |
1402 | * starting at the end. | |
56521e7a | 1403 | */ |
e130242d AB |
1404 | while (maxnode > MAX_NUMNODES) { |
1405 | unsigned long bits = min_t(unsigned long, maxnode, BITS_PER_LONG); | |
1406 | unsigned long t; | |
8bccd85f | 1407 | |
e130242d | 1408 | if (get_bitmap(&t, &nmask[maxnode / BITS_PER_LONG], bits)) |
56521e7a | 1409 | return -EFAULT; |
e130242d AB |
1410 | |
1411 | if (maxnode - bits >= MAX_NUMNODES) { | |
1412 | maxnode -= bits; | |
1413 | } else { | |
1414 | maxnode = MAX_NUMNODES; | |
1415 | t &= ~((1UL << (MAX_NUMNODES % BITS_PER_LONG)) - 1); | |
1416 | } | |
1417 | if (t) | |
56521e7a YX |
1418 | return -EINVAL; |
1419 | } | |
1420 | ||
e130242d | 1421 | return get_bitmap(nodes_addr(*nodes), nmask, maxnode); |
8bccd85f CL |
1422 | } |
1423 | ||
1424 | /* Copy a kernel node mask to user space */ | |
1425 | static int copy_nodes_to_user(unsigned long __user *mask, unsigned long maxnode, | |
1426 | nodemask_t *nodes) | |
1427 | { | |
1428 | unsigned long copy = ALIGN(maxnode-1, 64) / 8; | |
050c17f2 | 1429 | unsigned int nbytes = BITS_TO_LONGS(nr_node_ids) * sizeof(long); |
e130242d AB |
1430 | bool compat = in_compat_syscall(); |
1431 | ||
1432 | if (compat) | |
1433 | nbytes = BITS_TO_COMPAT_LONGS(nr_node_ids) * sizeof(compat_long_t); | |
8bccd85f CL |
1434 | |
1435 | if (copy > nbytes) { | |
1436 | if (copy > PAGE_SIZE) | |
1437 | return -EINVAL; | |
1438 | if (clear_user((char __user *)mask + nbytes, copy - nbytes)) | |
1439 | return -EFAULT; | |
1440 | copy = nbytes; | |
e130242d | 1441 | maxnode = nr_node_ids; |
8bccd85f | 1442 | } |
e130242d AB |
1443 | |
1444 | if (compat) | |
1445 | return compat_put_bitmap((compat_ulong_t __user *)mask, | |
1446 | nodes_addr(*nodes), maxnode); | |
1447 | ||
8bccd85f CL |
1448 | return copy_to_user(mask, nodes_addr(*nodes), copy) ? -EFAULT : 0; |
1449 | } | |
1450 | ||
95837924 FT |
1451 | /* Basic parameter sanity check used by both mbind() and set_mempolicy() */ |
1452 | static inline int sanitize_mpol_flags(int *mode, unsigned short *flags) | |
1453 | { | |
1454 | *flags = *mode & MPOL_MODE_FLAGS; | |
1455 | *mode &= ~MPOL_MODE_FLAGS; | |
b27abacc | 1456 | |
a38a59fd | 1457 | if ((unsigned int)(*mode) >= MPOL_MAX) |
95837924 FT |
1458 | return -EINVAL; |
1459 | if ((*flags & MPOL_F_STATIC_NODES) && (*flags & MPOL_F_RELATIVE_NODES)) | |
1460 | return -EINVAL; | |
1461 | ||
1462 | return 0; | |
1463 | } | |
1464 | ||
e7dc9ad6 DB |
1465 | static long kernel_mbind(unsigned long start, unsigned long len, |
1466 | unsigned long mode, const unsigned long __user *nmask, | |
1467 | unsigned long maxnode, unsigned int flags) | |
8bccd85f | 1468 | { |
95837924 | 1469 | unsigned short mode_flags; |
8bccd85f | 1470 | nodemask_t nodes; |
95837924 | 1471 | int lmode = mode; |
8bccd85f CL |
1472 | int err; |
1473 | ||
057d3389 | 1474 | start = untagged_addr(start); |
95837924 FT |
1475 | err = sanitize_mpol_flags(&lmode, &mode_flags); |
1476 | if (err) | |
1477 | return err; | |
1478 | ||
8bccd85f CL |
1479 | err = get_nodes(&nodes, nmask, maxnode); |
1480 | if (err) | |
1481 | return err; | |
95837924 FT |
1482 | |
1483 | return do_mbind(start, len, lmode, mode_flags, &nodes, flags); | |
8bccd85f CL |
1484 | } |
1485 | ||
e7dc9ad6 DB |
1486 | SYSCALL_DEFINE6(mbind, unsigned long, start, unsigned long, len, |
1487 | unsigned long, mode, const unsigned long __user *, nmask, | |
1488 | unsigned long, maxnode, unsigned int, flags) | |
1489 | { | |
1490 | return kernel_mbind(start, len, mode, nmask, maxnode, flags); | |
1491 | } | |
1492 | ||
8bccd85f | 1493 | /* Set the process memory policy */ |
af03c4ac DB |
1494 | static long kernel_set_mempolicy(int mode, const unsigned long __user *nmask, |
1495 | unsigned long maxnode) | |
8bccd85f | 1496 | { |
95837924 | 1497 | unsigned short mode_flags; |
8bccd85f | 1498 | nodemask_t nodes; |
95837924 FT |
1499 | int lmode = mode; |
1500 | int err; | |
1501 | ||
1502 | err = sanitize_mpol_flags(&lmode, &mode_flags); | |
1503 | if (err) | |
1504 | return err; | |
8bccd85f | 1505 | |
8bccd85f CL |
1506 | err = get_nodes(&nodes, nmask, maxnode); |
1507 | if (err) | |
1508 | return err; | |
95837924 FT |
1509 | |
1510 | return do_set_mempolicy(lmode, mode_flags, &nodes); | |
8bccd85f CL |
1511 | } |
1512 | ||
af03c4ac DB |
1513 | SYSCALL_DEFINE3(set_mempolicy, int, mode, const unsigned long __user *, nmask, |
1514 | unsigned long, maxnode) | |
1515 | { | |
1516 | return kernel_set_mempolicy(mode, nmask, maxnode); | |
1517 | } | |
1518 | ||
b6e9b0ba DB |
1519 | static int kernel_migrate_pages(pid_t pid, unsigned long maxnode, |
1520 | const unsigned long __user *old_nodes, | |
1521 | const unsigned long __user *new_nodes) | |
39743889 | 1522 | { |
596d7cfa | 1523 | struct mm_struct *mm = NULL; |
39743889 | 1524 | struct task_struct *task; |
39743889 CL |
1525 | nodemask_t task_nodes; |
1526 | int err; | |
596d7cfa KM |
1527 | nodemask_t *old; |
1528 | nodemask_t *new; | |
1529 | NODEMASK_SCRATCH(scratch); | |
1530 | ||
1531 | if (!scratch) | |
1532 | return -ENOMEM; | |
39743889 | 1533 | |
596d7cfa KM |
1534 | old = &scratch->mask1; |
1535 | new = &scratch->mask2; | |
1536 | ||
1537 | err = get_nodes(old, old_nodes, maxnode); | |
39743889 | 1538 | if (err) |
596d7cfa | 1539 | goto out; |
39743889 | 1540 | |
596d7cfa | 1541 | err = get_nodes(new, new_nodes, maxnode); |
39743889 | 1542 | if (err) |
596d7cfa | 1543 | goto out; |
39743889 CL |
1544 | |
1545 | /* Find the mm_struct */ | |
55cfaa3c | 1546 | rcu_read_lock(); |
228ebcbe | 1547 | task = pid ? find_task_by_vpid(pid) : current; |
39743889 | 1548 | if (!task) { |
55cfaa3c | 1549 | rcu_read_unlock(); |
596d7cfa KM |
1550 | err = -ESRCH; |
1551 | goto out; | |
39743889 | 1552 | } |
3268c63e | 1553 | get_task_struct(task); |
39743889 | 1554 | |
596d7cfa | 1555 | err = -EINVAL; |
39743889 CL |
1556 | |
1557 | /* | |
31367466 OE |
1558 | * Check if this process has the right to modify the specified process. |
1559 | * Use the regular "ptrace_may_access()" checks. | |
39743889 | 1560 | */ |
31367466 | 1561 | if (!ptrace_may_access(task, PTRACE_MODE_READ_REALCREDS)) { |
c69e8d9c | 1562 | rcu_read_unlock(); |
39743889 | 1563 | err = -EPERM; |
3268c63e | 1564 | goto out_put; |
39743889 | 1565 | } |
c69e8d9c | 1566 | rcu_read_unlock(); |
39743889 CL |
1567 | |
1568 | task_nodes = cpuset_mems_allowed(task); | |
1569 | /* Is the user allowed to access the target nodes? */ | |
596d7cfa | 1570 | if (!nodes_subset(*new, task_nodes) && !capable(CAP_SYS_NICE)) { |
39743889 | 1571 | err = -EPERM; |
3268c63e | 1572 | goto out_put; |
39743889 CL |
1573 | } |
1574 | ||
0486a38b YX |
1575 | task_nodes = cpuset_mems_allowed(current); |
1576 | nodes_and(*new, *new, task_nodes); | |
1577 | if (nodes_empty(*new)) | |
1578 | goto out_put; | |
1579 | ||
86c3a764 DQ |
1580 | err = security_task_movememory(task); |
1581 | if (err) | |
3268c63e | 1582 | goto out_put; |
86c3a764 | 1583 | |
3268c63e CL |
1584 | mm = get_task_mm(task); |
1585 | put_task_struct(task); | |
f2a9ef88 SL |
1586 | |
1587 | if (!mm) { | |
3268c63e | 1588 | err = -EINVAL; |
f2a9ef88 SL |
1589 | goto out; |
1590 | } | |
1591 | ||
1592 | err = do_migrate_pages(mm, old, new, | |
1593 | capable(CAP_SYS_NICE) ? MPOL_MF_MOVE_ALL : MPOL_MF_MOVE); | |
3268c63e CL |
1594 | |
1595 | mmput(mm); | |
1596 | out: | |
596d7cfa KM |
1597 | NODEMASK_SCRATCH_FREE(scratch); |
1598 | ||
39743889 | 1599 | return err; |
3268c63e CL |
1600 | |
1601 | out_put: | |
1602 | put_task_struct(task); | |
1603 | goto out; | |
1604 | ||
39743889 CL |
1605 | } |
1606 | ||
b6e9b0ba DB |
1607 | SYSCALL_DEFINE4(migrate_pages, pid_t, pid, unsigned long, maxnode, |
1608 | const unsigned long __user *, old_nodes, | |
1609 | const unsigned long __user *, new_nodes) | |
1610 | { | |
1611 | return kernel_migrate_pages(pid, maxnode, old_nodes, new_nodes); | |
1612 | } | |
1613 | ||
39743889 | 1614 | |
8bccd85f | 1615 | /* Retrieve NUMA policy */ |
af03c4ac DB |
1616 | static int kernel_get_mempolicy(int __user *policy, |
1617 | unsigned long __user *nmask, | |
1618 | unsigned long maxnode, | |
1619 | unsigned long addr, | |
1620 | unsigned long flags) | |
8bccd85f | 1621 | { |
dbcb0f19 | 1622 | int err; |
3f649ab7 | 1623 | int pval; |
8bccd85f CL |
1624 | nodemask_t nodes; |
1625 | ||
050c17f2 | 1626 | if (nmask != NULL && maxnode < nr_node_ids) |
8bccd85f CL |
1627 | return -EINVAL; |
1628 | ||
4605f057 WH |
1629 | addr = untagged_addr(addr); |
1630 | ||
8bccd85f CL |
1631 | err = do_get_mempolicy(&pval, &nodes, addr, flags); |
1632 | ||
1633 | if (err) | |
1634 | return err; | |
1635 | ||
1636 | if (policy && put_user(pval, policy)) | |
1637 | return -EFAULT; | |
1638 | ||
1639 | if (nmask) | |
1640 | err = copy_nodes_to_user(nmask, maxnode, &nodes); | |
1641 | ||
1642 | return err; | |
1643 | } | |
1644 | ||
af03c4ac DB |
1645 | SYSCALL_DEFINE5(get_mempolicy, int __user *, policy, |
1646 | unsigned long __user *, nmask, unsigned long, maxnode, | |
1647 | unsigned long, addr, unsigned long, flags) | |
1648 | { | |
1649 | return kernel_get_mempolicy(policy, nmask, maxnode, addr, flags); | |
1650 | } | |
1651 | ||
20ca87f2 LX |
1652 | bool vma_migratable(struct vm_area_struct *vma) |
1653 | { | |
1654 | if (vma->vm_flags & (VM_IO | VM_PFNMAP)) | |
1655 | return false; | |
1656 | ||
1657 | /* | |
1658 | * DAX device mappings require predictable access latency, so avoid | |
1659 | * incurring periodic faults. | |
1660 | */ | |
1661 | if (vma_is_dax(vma)) | |
1662 | return false; | |
1663 | ||
1664 | if (is_vm_hugetlb_page(vma) && | |
1665 | !hugepage_migration_supported(hstate_vma(vma))) | |
1666 | return false; | |
1667 | ||
1668 | /* | |
1669 | * Migration allocates pages in the highest zone. If we cannot | |
1670 | * do so then migration (at least from node to node) is not | |
1671 | * possible. | |
1672 | */ | |
1673 | if (vma->vm_file && | |
1674 | gfp_zone(mapping_gfp_mask(vma->vm_file->f_mapping)) | |
1675 | < policy_zone) | |
1676 | return false; | |
1677 | return true; | |
1678 | } | |
1679 | ||
74d2c3a0 ON |
1680 | struct mempolicy *__get_vma_policy(struct vm_area_struct *vma, |
1681 | unsigned long addr) | |
1da177e4 | 1682 | { |
8d90274b | 1683 | struct mempolicy *pol = NULL; |
1da177e4 LT |
1684 | |
1685 | if (vma) { | |
480eccf9 | 1686 | if (vma->vm_ops && vma->vm_ops->get_policy) { |
8d90274b | 1687 | pol = vma->vm_ops->get_policy(vma, addr); |
00442ad0 | 1688 | } else if (vma->vm_policy) { |
1da177e4 | 1689 | pol = vma->vm_policy; |
00442ad0 MG |
1690 | |
1691 | /* | |
1692 | * shmem_alloc_page() passes MPOL_F_SHARED policy with | |
1693 | * a pseudo vma whose vma->vm_ops=NULL. Take a reference | |
1694 | * count on these policies which will be dropped by | |
1695 | * mpol_cond_put() later | |
1696 | */ | |
1697 | if (mpol_needs_cond_ref(pol)) | |
1698 | mpol_get(pol); | |
1699 | } | |
1da177e4 | 1700 | } |
f15ca78e | 1701 | |
74d2c3a0 ON |
1702 | return pol; |
1703 | } | |
1704 | ||
1705 | /* | |
dd6eecb9 | 1706 | * get_vma_policy(@vma, @addr) |
74d2c3a0 ON |
1707 | * @vma: virtual memory area whose policy is sought |
1708 | * @addr: address in @vma for shared policy lookup | |
1709 | * | |
1710 | * Returns effective policy for a VMA at specified address. | |
dd6eecb9 | 1711 | * Falls back to current->mempolicy or system default policy, as necessary. |
74d2c3a0 ON |
1712 | * Shared policies [those marked as MPOL_F_SHARED] require an extra reference |
1713 | * count--added by the get_policy() vm_op, as appropriate--to protect against | |
1714 | * freeing by another task. It is the caller's responsibility to free the | |
1715 | * extra reference for shared policies. | |
1716 | */ | |
ac79f78d | 1717 | static struct mempolicy *get_vma_policy(struct vm_area_struct *vma, |
dd6eecb9 | 1718 | unsigned long addr) |
74d2c3a0 ON |
1719 | { |
1720 | struct mempolicy *pol = __get_vma_policy(vma, addr); | |
1721 | ||
8d90274b | 1722 | if (!pol) |
dd6eecb9 | 1723 | pol = get_task_policy(current); |
8d90274b | 1724 | |
1da177e4 LT |
1725 | return pol; |
1726 | } | |
1727 | ||
6b6482bb | 1728 | bool vma_policy_mof(struct vm_area_struct *vma) |
fc314724 | 1729 | { |
6b6482bb | 1730 | struct mempolicy *pol; |
fc314724 | 1731 | |
6b6482bb ON |
1732 | if (vma->vm_ops && vma->vm_ops->get_policy) { |
1733 | bool ret = false; | |
fc314724 | 1734 | |
6b6482bb ON |
1735 | pol = vma->vm_ops->get_policy(vma, vma->vm_start); |
1736 | if (pol && (pol->flags & MPOL_F_MOF)) | |
1737 | ret = true; | |
1738 | mpol_cond_put(pol); | |
8d90274b | 1739 | |
6b6482bb | 1740 | return ret; |
fc314724 MG |
1741 | } |
1742 | ||
6b6482bb | 1743 | pol = vma->vm_policy; |
8d90274b | 1744 | if (!pol) |
6b6482bb | 1745 | pol = get_task_policy(current); |
8d90274b | 1746 | |
fc314724 MG |
1747 | return pol->flags & MPOL_F_MOF; |
1748 | } | |
1749 | ||
d3eb1570 LJ |
1750 | static int apply_policy_zone(struct mempolicy *policy, enum zone_type zone) |
1751 | { | |
1752 | enum zone_type dynamic_policy_zone = policy_zone; | |
1753 | ||
1754 | BUG_ON(dynamic_policy_zone == ZONE_MOVABLE); | |
1755 | ||
1756 | /* | |
269fbe72 | 1757 | * if policy->nodes has movable memory only, |
d3eb1570 LJ |
1758 | * we apply policy when gfp_zone(gfp) = ZONE_MOVABLE only. |
1759 | * | |
269fbe72 | 1760 | * policy->nodes is intersect with node_states[N_MEMORY]. |
f0953a1b | 1761 | * so if the following test fails, it implies |
269fbe72 | 1762 | * policy->nodes has movable memory only. |
d3eb1570 | 1763 | */ |
269fbe72 | 1764 | if (!nodes_intersects(policy->nodes, node_states[N_HIGH_MEMORY])) |
d3eb1570 LJ |
1765 | dynamic_policy_zone = ZONE_MOVABLE; |
1766 | ||
1767 | return zone >= dynamic_policy_zone; | |
1768 | } | |
1769 | ||
52cd3b07 LS |
1770 | /* |
1771 | * Return a nodemask representing a mempolicy for filtering nodes for | |
1772 | * page allocation | |
1773 | */ | |
8ca39e68 | 1774 | nodemask_t *policy_nodemask(gfp_t gfp, struct mempolicy *policy) |
19770b32 | 1775 | { |
b27abacc DH |
1776 | int mode = policy->mode; |
1777 | ||
19770b32 | 1778 | /* Lower zones don't get a nodemask applied for MPOL_BIND */ |
b27abacc DH |
1779 | if (unlikely(mode == MPOL_BIND) && |
1780 | apply_policy_zone(policy, gfp_zone(gfp)) && | |
1781 | cpuset_nodemask_valid_mems_allowed(&policy->nodes)) | |
1782 | return &policy->nodes; | |
1783 | ||
1784 | if (mode == MPOL_PREFERRED_MANY) | |
269fbe72 | 1785 | return &policy->nodes; |
19770b32 MG |
1786 | |
1787 | return NULL; | |
1788 | } | |
1789 | ||
b27abacc DH |
1790 | /* |
1791 | * Return the preferred node id for 'prefer' mempolicy, and return | |
1792 | * the given id for all other policies. | |
1793 | * | |
1794 | * policy_node() is always coupled with policy_nodemask(), which | |
1795 | * secures the nodemask limit for 'bind' and 'prefer-many' policy. | |
1796 | */ | |
f8fd5253 | 1797 | static int policy_node(gfp_t gfp, struct mempolicy *policy, int nd) |
1da177e4 | 1798 | { |
7858d7bc | 1799 | if (policy->mode == MPOL_PREFERRED) { |
269fbe72 | 1800 | nd = first_node(policy->nodes); |
7858d7bc | 1801 | } else { |
19770b32 | 1802 | /* |
6d840958 MH |
1803 | * __GFP_THISNODE shouldn't even be used with the bind policy |
1804 | * because we might easily break the expectation to stay on the | |
1805 | * requested node and not break the policy. | |
19770b32 | 1806 | */ |
6d840958 | 1807 | WARN_ON_ONCE(policy->mode == MPOL_BIND && (gfp & __GFP_THISNODE)); |
1da177e4 | 1808 | } |
6d840958 | 1809 | |
04ec6264 | 1810 | return nd; |
1da177e4 LT |
1811 | } |
1812 | ||
1813 | /* Do dynamic interleaving for a process */ | |
1814 | static unsigned interleave_nodes(struct mempolicy *policy) | |
1815 | { | |
45816682 | 1816 | unsigned next; |
1da177e4 LT |
1817 | struct task_struct *me = current; |
1818 | ||
269fbe72 | 1819 | next = next_node_in(me->il_prev, policy->nodes); |
f5b087b5 | 1820 | if (next < MAX_NUMNODES) |
45816682 VB |
1821 | me->il_prev = next; |
1822 | return next; | |
1da177e4 LT |
1823 | } |
1824 | ||
dc85da15 CL |
1825 | /* |
1826 | * Depending on the memory policy provide a node from which to allocate the | |
1827 | * next slab entry. | |
1828 | */ | |
2a389610 | 1829 | unsigned int mempolicy_slab_node(void) |
dc85da15 | 1830 | { |
e7b691b0 | 1831 | struct mempolicy *policy; |
2a389610 | 1832 | int node = numa_mem_id(); |
e7b691b0 | 1833 | |
38b031dd | 1834 | if (!in_task()) |
2a389610 | 1835 | return node; |
e7b691b0 AK |
1836 | |
1837 | policy = current->mempolicy; | |
7858d7bc | 1838 | if (!policy) |
2a389610 | 1839 | return node; |
bea904d5 LS |
1840 | |
1841 | switch (policy->mode) { | |
1842 | case MPOL_PREFERRED: | |
269fbe72 | 1843 | return first_node(policy->nodes); |
765c4507 | 1844 | |
dc85da15 CL |
1845 | case MPOL_INTERLEAVE: |
1846 | return interleave_nodes(policy); | |
1847 | ||
b27abacc DH |
1848 | case MPOL_BIND: |
1849 | case MPOL_PREFERRED_MANY: | |
1850 | { | |
c33d6c06 MG |
1851 | struct zoneref *z; |
1852 | ||
dc85da15 CL |
1853 | /* |
1854 | * Follow bind policy behavior and start allocation at the | |
1855 | * first node. | |
1856 | */ | |
19770b32 | 1857 | struct zonelist *zonelist; |
19770b32 | 1858 | enum zone_type highest_zoneidx = gfp_zone(GFP_KERNEL); |
c9634cf0 | 1859 | zonelist = &NODE_DATA(node)->node_zonelists[ZONELIST_FALLBACK]; |
c33d6c06 | 1860 | z = first_zones_zonelist(zonelist, highest_zoneidx, |
269fbe72 | 1861 | &policy->nodes); |
c1093b74 | 1862 | return z->zone ? zone_to_nid(z->zone) : node; |
dd1a239f | 1863 | } |
7858d7bc FT |
1864 | case MPOL_LOCAL: |
1865 | return node; | |
dc85da15 | 1866 | |
dc85da15 | 1867 | default: |
bea904d5 | 1868 | BUG(); |
dc85da15 CL |
1869 | } |
1870 | } | |
1871 | ||
fee83b3a AM |
1872 | /* |
1873 | * Do static interleaving for a VMA with known offset @n. Returns the n'th | |
269fbe72 | 1874 | * node in pol->nodes (starting from n=0), wrapping around if n exceeds the |
fee83b3a AM |
1875 | * number of present nodes. |
1876 | */ | |
98c70baa | 1877 | static unsigned offset_il_node(struct mempolicy *pol, unsigned long n) |
1da177e4 | 1878 | { |
276aeee1 | 1879 | nodemask_t nodemask = pol->nodes; |
1880 | unsigned int target, nnodes; | |
fee83b3a AM |
1881 | int i; |
1882 | int nid; | |
276aeee1 | 1883 | /* |
1884 | * The barrier will stabilize the nodemask in a register or on | |
1885 | * the stack so that it will stop changing under the code. | |
1886 | * | |
1887 | * Between first_node() and next_node(), pol->nodes could be changed | |
1888 | * by other threads. So we put pol->nodes in a local stack. | |
1889 | */ | |
1890 | barrier(); | |
1da177e4 | 1891 | |
276aeee1 | 1892 | nnodes = nodes_weight(nodemask); |
f5b087b5 DR |
1893 | if (!nnodes) |
1894 | return numa_node_id(); | |
fee83b3a | 1895 | target = (unsigned int)n % nnodes; |
276aeee1 | 1896 | nid = first_node(nodemask); |
fee83b3a | 1897 | for (i = 0; i < target; i++) |
276aeee1 | 1898 | nid = next_node(nid, nodemask); |
1da177e4 LT |
1899 | return nid; |
1900 | } | |
1901 | ||
5da7ca86 CL |
1902 | /* Determine a node number for interleave */ |
1903 | static inline unsigned interleave_nid(struct mempolicy *pol, | |
1904 | struct vm_area_struct *vma, unsigned long addr, int shift) | |
1905 | { | |
1906 | if (vma) { | |
1907 | unsigned long off; | |
1908 | ||
3b98b087 NA |
1909 | /* |
1910 | * for small pages, there is no difference between | |
1911 | * shift and PAGE_SHIFT, so the bit-shift is safe. | |
1912 | * for huge pages, since vm_pgoff is in units of small | |
1913 | * pages, we need to shift off the always 0 bits to get | |
1914 | * a useful offset. | |
1915 | */ | |
1916 | BUG_ON(shift < PAGE_SHIFT); | |
1917 | off = vma->vm_pgoff >> (shift - PAGE_SHIFT); | |
5da7ca86 | 1918 | off += (addr - vma->vm_start) >> shift; |
98c70baa | 1919 | return offset_il_node(pol, off); |
5da7ca86 CL |
1920 | } else |
1921 | return interleave_nodes(pol); | |
1922 | } | |
1923 | ||
00ac59ad | 1924 | #ifdef CONFIG_HUGETLBFS |
480eccf9 | 1925 | /* |
04ec6264 | 1926 | * huge_node(@vma, @addr, @gfp_flags, @mpol) |
b46e14ac FF |
1927 | * @vma: virtual memory area whose policy is sought |
1928 | * @addr: address in @vma for shared policy lookup and interleave policy | |
1929 | * @gfp_flags: for requested zone | |
1930 | * @mpol: pointer to mempolicy pointer for reference counted mempolicy | |
b27abacc | 1931 | * @nodemask: pointer to nodemask pointer for 'bind' and 'prefer-many' policy |
480eccf9 | 1932 | * |
04ec6264 | 1933 | * Returns a nid suitable for a huge page allocation and a pointer |
52cd3b07 | 1934 | * to the struct mempolicy for conditional unref after allocation. |
b27abacc DH |
1935 | * If the effective policy is 'bind' or 'prefer-many', returns a pointer |
1936 | * to the mempolicy's @nodemask for filtering the zonelist. | |
c0ff7453 | 1937 | * |
d26914d1 | 1938 | * Must be protected by read_mems_allowed_begin() |
480eccf9 | 1939 | */ |
04ec6264 VB |
1940 | int huge_node(struct vm_area_struct *vma, unsigned long addr, gfp_t gfp_flags, |
1941 | struct mempolicy **mpol, nodemask_t **nodemask) | |
5da7ca86 | 1942 | { |
04ec6264 | 1943 | int nid; |
b27abacc | 1944 | int mode; |
5da7ca86 | 1945 | |
dd6eecb9 | 1946 | *mpol = get_vma_policy(vma, addr); |
b27abacc DH |
1947 | *nodemask = NULL; |
1948 | mode = (*mpol)->mode; | |
5da7ca86 | 1949 | |
b27abacc | 1950 | if (unlikely(mode == MPOL_INTERLEAVE)) { |
04ec6264 VB |
1951 | nid = interleave_nid(*mpol, vma, addr, |
1952 | huge_page_shift(hstate_vma(vma))); | |
52cd3b07 | 1953 | } else { |
04ec6264 | 1954 | nid = policy_node(gfp_flags, *mpol, numa_node_id()); |
b27abacc | 1955 | if (mode == MPOL_BIND || mode == MPOL_PREFERRED_MANY) |
269fbe72 | 1956 | *nodemask = &(*mpol)->nodes; |
480eccf9 | 1957 | } |
04ec6264 | 1958 | return nid; |
5da7ca86 | 1959 | } |
06808b08 LS |
1960 | |
1961 | /* | |
1962 | * init_nodemask_of_mempolicy | |
1963 | * | |
1964 | * If the current task's mempolicy is "default" [NULL], return 'false' | |
1965 | * to indicate default policy. Otherwise, extract the policy nodemask | |
1966 | * for 'bind' or 'interleave' policy into the argument nodemask, or | |
1967 | * initialize the argument nodemask to contain the single node for | |
1968 | * 'preferred' or 'local' policy and return 'true' to indicate presence | |
1969 | * of non-default mempolicy. | |
1970 | * | |
1971 | * We don't bother with reference counting the mempolicy [mpol_get/put] | |
1972 | * because the current task is examining it's own mempolicy and a task's | |
1973 | * mempolicy is only ever changed by the task itself. | |
1974 | * | |
1975 | * N.B., it is the caller's responsibility to free a returned nodemask. | |
1976 | */ | |
1977 | bool init_nodemask_of_mempolicy(nodemask_t *mask) | |
1978 | { | |
1979 | struct mempolicy *mempolicy; | |
06808b08 LS |
1980 | |
1981 | if (!(mask && current->mempolicy)) | |
1982 | return false; | |
1983 | ||
c0ff7453 | 1984 | task_lock(current); |
06808b08 LS |
1985 | mempolicy = current->mempolicy; |
1986 | switch (mempolicy->mode) { | |
1987 | case MPOL_PREFERRED: | |
b27abacc | 1988 | case MPOL_PREFERRED_MANY: |
06808b08 | 1989 | case MPOL_BIND: |
06808b08 | 1990 | case MPOL_INTERLEAVE: |
269fbe72 | 1991 | *mask = mempolicy->nodes; |
7858d7bc FT |
1992 | break; |
1993 | ||
1994 | case MPOL_LOCAL: | |
269fbe72 | 1995 | init_nodemask_of_node(mask, numa_node_id()); |
06808b08 LS |
1996 | break; |
1997 | ||
1998 | default: | |
1999 | BUG(); | |
2000 | } | |
c0ff7453 | 2001 | task_unlock(current); |
06808b08 LS |
2002 | |
2003 | return true; | |
2004 | } | |
00ac59ad | 2005 | #endif |
5da7ca86 | 2006 | |
6f48d0eb | 2007 | /* |
b26e517a | 2008 | * mempolicy_in_oom_domain |
6f48d0eb | 2009 | * |
b26e517a FT |
2010 | * If tsk's mempolicy is "bind", check for intersection between mask and |
2011 | * the policy nodemask. Otherwise, return true for all other policies | |
2012 | * including "interleave", as a tsk with "interleave" policy may have | |
2013 | * memory allocated from all nodes in system. | |
6f48d0eb DR |
2014 | * |
2015 | * Takes task_lock(tsk) to prevent freeing of its mempolicy. | |
2016 | */ | |
b26e517a | 2017 | bool mempolicy_in_oom_domain(struct task_struct *tsk, |
6f48d0eb DR |
2018 | const nodemask_t *mask) |
2019 | { | |
2020 | struct mempolicy *mempolicy; | |
2021 | bool ret = true; | |
2022 | ||
2023 | if (!mask) | |
2024 | return ret; | |
b26e517a | 2025 | |
6f48d0eb DR |
2026 | task_lock(tsk); |
2027 | mempolicy = tsk->mempolicy; | |
b26e517a | 2028 | if (mempolicy && mempolicy->mode == MPOL_BIND) |
269fbe72 | 2029 | ret = nodes_intersects(mempolicy->nodes, *mask); |
6f48d0eb | 2030 | task_unlock(tsk); |
b26e517a | 2031 | |
6f48d0eb DR |
2032 | return ret; |
2033 | } | |
2034 | ||
1da177e4 LT |
2035 | /* Allocate a page in interleaved policy. |
2036 | Own path because it needs to do special accounting. */ | |
662f3a0b AK |
2037 | static struct page *alloc_page_interleave(gfp_t gfp, unsigned order, |
2038 | unsigned nid) | |
1da177e4 | 2039 | { |
1da177e4 LT |
2040 | struct page *page; |
2041 | ||
84172f4b | 2042 | page = __alloc_pages(gfp, order, nid, NULL); |
4518085e KW |
2043 | /* skip NUMA_INTERLEAVE_HIT counter update if numa stats is disabled */ |
2044 | if (!static_branch_likely(&vm_numa_stat_key)) | |
2045 | return page; | |
de55c8b2 AR |
2046 | if (page && page_to_nid(page) == nid) { |
2047 | preempt_disable(); | |
f19298b9 | 2048 | __count_numa_event(page_zone(page), NUMA_INTERLEAVE_HIT); |
de55c8b2 AR |
2049 | preempt_enable(); |
2050 | } | |
1da177e4 LT |
2051 | return page; |
2052 | } | |
2053 | ||
4c54d949 FT |
2054 | static struct page *alloc_pages_preferred_many(gfp_t gfp, unsigned int order, |
2055 | int nid, struct mempolicy *pol) | |
2056 | { | |
2057 | struct page *page; | |
2058 | gfp_t preferred_gfp; | |
2059 | ||
2060 | /* | |
2061 | * This is a two pass approach. The first pass will only try the | |
2062 | * preferred nodes but skip the direct reclaim and allow the | |
2063 | * allocation to fail, while the second pass will try all the | |
2064 | * nodes in system. | |
2065 | */ | |
2066 | preferred_gfp = gfp | __GFP_NOWARN; | |
2067 | preferred_gfp &= ~(__GFP_DIRECT_RECLAIM | __GFP_NOFAIL); | |
2068 | page = __alloc_pages(preferred_gfp, order, nid, &pol->nodes); | |
2069 | if (!page) | |
2070 | page = __alloc_pages(gfp, order, numa_node_id(), NULL); | |
2071 | ||
2072 | return page; | |
2073 | } | |
2074 | ||
1da177e4 | 2075 | /** |
eb350739 MWO |
2076 | * alloc_pages_vma - Allocate a page for a VMA. |
2077 | * @gfp: GFP flags. | |
2078 | * @order: Order of the GFP allocation. | |
2079 | * @vma: Pointer to VMA or NULL if not available. | |
2080 | * @addr: Virtual address of the allocation. Must be inside @vma. | |
2081 | * @node: Which node to prefer for allocation (modulo policy). | |
2082 | * @hugepage: For hugepages try only the preferred node if possible. | |
1da177e4 | 2083 | * |
eb350739 MWO |
2084 | * Allocate a page for a specific address in @vma, using the appropriate |
2085 | * NUMA policy. When @vma is not NULL the caller must hold the mmap_lock | |
2086 | * of the mm_struct of the VMA to prevent it from going away. Should be | |
2087 | * used for all allocations for pages that will be mapped into user space. | |
1da177e4 | 2088 | * |
eb350739 | 2089 | * Return: The page on success or NULL if allocation fails. |
1da177e4 | 2090 | */ |
eb350739 | 2091 | struct page *alloc_pages_vma(gfp_t gfp, int order, struct vm_area_struct *vma, |
19deb769 | 2092 | unsigned long addr, int node, bool hugepage) |
1da177e4 | 2093 | { |
cc9a6c87 | 2094 | struct mempolicy *pol; |
c0ff7453 | 2095 | struct page *page; |
04ec6264 | 2096 | int preferred_nid; |
be97a41b | 2097 | nodemask_t *nmask; |
cc9a6c87 | 2098 | |
dd6eecb9 | 2099 | pol = get_vma_policy(vma, addr); |
1da177e4 | 2100 | |
0867a57c VB |
2101 | if (pol->mode == MPOL_INTERLEAVE) { |
2102 | unsigned nid; | |
2103 | ||
2104 | nid = interleave_nid(pol, vma, addr, PAGE_SHIFT + order); | |
2105 | mpol_cond_put(pol); | |
2106 | page = alloc_page_interleave(gfp, order, nid); | |
2107 | goto out; | |
19deb769 DR |
2108 | } |
2109 | ||
4c54d949 FT |
2110 | if (pol->mode == MPOL_PREFERRED_MANY) { |
2111 | page = alloc_pages_preferred_many(gfp, order, node, pol); | |
2112 | mpol_cond_put(pol); | |
2113 | goto out; | |
2114 | } | |
2115 | ||
19deb769 DR |
2116 | if (unlikely(IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE) && hugepage)) { |
2117 | int hpage_node = node; | |
2118 | ||
2119 | /* | |
2120 | * For hugepage allocation and non-interleave policy which | |
2121 | * allows the current node (or other explicitly preferred | |
2122 | * node) we only try to allocate from the current/preferred | |
2123 | * node and don't fall back to other nodes, as the cost of | |
2124 | * remote accesses would likely offset THP benefits. | |
2125 | * | |
b27abacc | 2126 | * If the policy is interleave or does not allow the current |
19deb769 DR |
2127 | * node in its nodemask, we allocate the standard way. |
2128 | */ | |
7858d7bc | 2129 | if (pol->mode == MPOL_PREFERRED) |
269fbe72 | 2130 | hpage_node = first_node(pol->nodes); |
19deb769 DR |
2131 | |
2132 | nmask = policy_nodemask(gfp, pol); | |
2133 | if (!nmask || node_isset(hpage_node, *nmask)) { | |
2134 | mpol_cond_put(pol); | |
cc638f32 VB |
2135 | /* |
2136 | * First, try to allocate THP only on local node, but | |
2137 | * don't reclaim unnecessarily, just compact. | |
2138 | */ | |
19deb769 | 2139 | page = __alloc_pages_node(hpage_node, |
cc638f32 | 2140 | gfp | __GFP_THISNODE | __GFP_NORETRY, order); |
76e654cc DR |
2141 | |
2142 | /* | |
2143 | * If hugepage allocations are configured to always | |
2144 | * synchronous compact or the vma has been madvised | |
2145 | * to prefer hugepage backing, retry allowing remote | |
cc638f32 | 2146 | * memory with both reclaim and compact as well. |
76e654cc DR |
2147 | */ |
2148 | if (!page && (gfp & __GFP_DIRECT_RECLAIM)) | |
2149 | page = __alloc_pages_node(hpage_node, | |
cc638f32 | 2150 | gfp, order); |
76e654cc | 2151 | |
19deb769 DR |
2152 | goto out; |
2153 | } | |
356ff8a9 DR |
2154 | } |
2155 | ||
be97a41b | 2156 | nmask = policy_nodemask(gfp, pol); |
04ec6264 | 2157 | preferred_nid = policy_node(gfp, pol, node); |
84172f4b | 2158 | page = __alloc_pages(gfp, order, preferred_nid, nmask); |
d51e9894 | 2159 | mpol_cond_put(pol); |
be97a41b | 2160 | out: |
c0ff7453 | 2161 | return page; |
1da177e4 | 2162 | } |
69262215 | 2163 | EXPORT_SYMBOL(alloc_pages_vma); |
1da177e4 LT |
2164 | |
2165 | /** | |
6421ec76 MWO |
2166 | * alloc_pages - Allocate pages. |
2167 | * @gfp: GFP flags. | |
2168 | * @order: Power of two of number of pages to allocate. | |
1da177e4 | 2169 | * |
6421ec76 MWO |
2170 | * Allocate 1 << @order contiguous pages. The physical address of the |
2171 | * first page is naturally aligned (eg an order-3 allocation will be aligned | |
2172 | * to a multiple of 8 * PAGE_SIZE bytes). The NUMA policy of the current | |
2173 | * process is honoured when in process context. | |
1da177e4 | 2174 | * |
6421ec76 MWO |
2175 | * Context: Can be called from any context, providing the appropriate GFP |
2176 | * flags are used. | |
2177 | * Return: The page on success or NULL if allocation fails. | |
1da177e4 | 2178 | */ |
d7f946d0 | 2179 | struct page *alloc_pages(gfp_t gfp, unsigned order) |
1da177e4 | 2180 | { |
8d90274b | 2181 | struct mempolicy *pol = &default_policy; |
c0ff7453 | 2182 | struct page *page; |
1da177e4 | 2183 | |
8d90274b ON |
2184 | if (!in_interrupt() && !(gfp & __GFP_THISNODE)) |
2185 | pol = get_task_policy(current); | |
52cd3b07 LS |
2186 | |
2187 | /* | |
2188 | * No reference counting needed for current->mempolicy | |
2189 | * nor system default_policy | |
2190 | */ | |
45c4745a | 2191 | if (pol->mode == MPOL_INTERLEAVE) |
c0ff7453 | 2192 | page = alloc_page_interleave(gfp, order, interleave_nodes(pol)); |
4c54d949 FT |
2193 | else if (pol->mode == MPOL_PREFERRED_MANY) |
2194 | page = alloc_pages_preferred_many(gfp, order, | |
2195 | numa_node_id(), pol); | |
c0ff7453 | 2196 | else |
84172f4b | 2197 | page = __alloc_pages(gfp, order, |
04ec6264 | 2198 | policy_node(gfp, pol, numa_node_id()), |
5c4b4be3 | 2199 | policy_nodemask(gfp, pol)); |
cc9a6c87 | 2200 | |
c0ff7453 | 2201 | return page; |
1da177e4 | 2202 | } |
d7f946d0 | 2203 | EXPORT_SYMBOL(alloc_pages); |
1da177e4 | 2204 | |
ef0855d3 ON |
2205 | int vma_dup_policy(struct vm_area_struct *src, struct vm_area_struct *dst) |
2206 | { | |
2207 | struct mempolicy *pol = mpol_dup(vma_policy(src)); | |
2208 | ||
2209 | if (IS_ERR(pol)) | |
2210 | return PTR_ERR(pol); | |
2211 | dst->vm_policy = pol; | |
2212 | return 0; | |
2213 | } | |
2214 | ||
4225399a | 2215 | /* |
846a16bf | 2216 | * If mpol_dup() sees current->cpuset == cpuset_being_rebound, then it |
4225399a PJ |
2217 | * rebinds the mempolicy its copying by calling mpol_rebind_policy() |
2218 | * with the mems_allowed returned by cpuset_mems_allowed(). This | |
2219 | * keeps mempolicies cpuset relative after its cpuset moves. See | |
2220 | * further kernel/cpuset.c update_nodemask(). | |
708c1bbc MX |
2221 | * |
2222 | * current's mempolicy may be rebinded by the other task(the task that changes | |
2223 | * cpuset's mems), so we needn't do rebind work for current task. | |
4225399a | 2224 | */ |
4225399a | 2225 | |
846a16bf LS |
2226 | /* Slow path of a mempolicy duplicate */ |
2227 | struct mempolicy *__mpol_dup(struct mempolicy *old) | |
1da177e4 LT |
2228 | { |
2229 | struct mempolicy *new = kmem_cache_alloc(policy_cache, GFP_KERNEL); | |
2230 | ||
2231 | if (!new) | |
2232 | return ERR_PTR(-ENOMEM); | |
708c1bbc MX |
2233 | |
2234 | /* task's mempolicy is protected by alloc_lock */ | |
2235 | if (old == current->mempolicy) { | |
2236 | task_lock(current); | |
2237 | *new = *old; | |
2238 | task_unlock(current); | |
2239 | } else | |
2240 | *new = *old; | |
2241 | ||
4225399a PJ |
2242 | if (current_cpuset_is_being_rebound()) { |
2243 | nodemask_t mems = cpuset_mems_allowed(current); | |
213980c0 | 2244 | mpol_rebind_policy(new, &mems); |
4225399a | 2245 | } |
1da177e4 | 2246 | atomic_set(&new->refcnt, 1); |
1da177e4 LT |
2247 | return new; |
2248 | } | |
2249 | ||
2250 | /* Slow path of a mempolicy comparison */ | |
fcfb4dcc | 2251 | bool __mpol_equal(struct mempolicy *a, struct mempolicy *b) |
1da177e4 LT |
2252 | { |
2253 | if (!a || !b) | |
fcfb4dcc | 2254 | return false; |
45c4745a | 2255 | if (a->mode != b->mode) |
fcfb4dcc | 2256 | return false; |
19800502 | 2257 | if (a->flags != b->flags) |
fcfb4dcc | 2258 | return false; |
19800502 BL |
2259 | if (mpol_store_user_nodemask(a)) |
2260 | if (!nodes_equal(a->w.user_nodemask, b->w.user_nodemask)) | |
fcfb4dcc | 2261 | return false; |
19800502 | 2262 | |
45c4745a | 2263 | switch (a->mode) { |
19770b32 | 2264 | case MPOL_BIND: |
1da177e4 | 2265 | case MPOL_INTERLEAVE: |
1da177e4 | 2266 | case MPOL_PREFERRED: |
b27abacc | 2267 | case MPOL_PREFERRED_MANY: |
269fbe72 | 2268 | return !!nodes_equal(a->nodes, b->nodes); |
7858d7bc FT |
2269 | case MPOL_LOCAL: |
2270 | return true; | |
1da177e4 LT |
2271 | default: |
2272 | BUG(); | |
fcfb4dcc | 2273 | return false; |
1da177e4 LT |
2274 | } |
2275 | } | |
2276 | ||
1da177e4 LT |
2277 | /* |
2278 | * Shared memory backing store policy support. | |
2279 | * | |
2280 | * Remember policies even when nobody has shared memory mapped. | |
2281 | * The policies are kept in Red-Black tree linked from the inode. | |
4a8c7bb5 | 2282 | * They are protected by the sp->lock rwlock, which should be held |
1da177e4 LT |
2283 | * for any accesses to the tree. |
2284 | */ | |
2285 | ||
4a8c7bb5 NZ |
2286 | /* |
2287 | * lookup first element intersecting start-end. Caller holds sp->lock for | |
2288 | * reading or for writing | |
2289 | */ | |
1da177e4 LT |
2290 | static struct sp_node * |
2291 | sp_lookup(struct shared_policy *sp, unsigned long start, unsigned long end) | |
2292 | { | |
2293 | struct rb_node *n = sp->root.rb_node; | |
2294 | ||
2295 | while (n) { | |
2296 | struct sp_node *p = rb_entry(n, struct sp_node, nd); | |
2297 | ||
2298 | if (start >= p->end) | |
2299 | n = n->rb_right; | |
2300 | else if (end <= p->start) | |
2301 | n = n->rb_left; | |
2302 | else | |
2303 | break; | |
2304 | } | |
2305 | if (!n) | |
2306 | return NULL; | |
2307 | for (;;) { | |
2308 | struct sp_node *w = NULL; | |
2309 | struct rb_node *prev = rb_prev(n); | |
2310 | if (!prev) | |
2311 | break; | |
2312 | w = rb_entry(prev, struct sp_node, nd); | |
2313 | if (w->end <= start) | |
2314 | break; | |
2315 | n = prev; | |
2316 | } | |
2317 | return rb_entry(n, struct sp_node, nd); | |
2318 | } | |
2319 | ||
4a8c7bb5 NZ |
2320 | /* |
2321 | * Insert a new shared policy into the list. Caller holds sp->lock for | |
2322 | * writing. | |
2323 | */ | |
1da177e4 LT |
2324 | static void sp_insert(struct shared_policy *sp, struct sp_node *new) |
2325 | { | |
2326 | struct rb_node **p = &sp->root.rb_node; | |
2327 | struct rb_node *parent = NULL; | |
2328 | struct sp_node *nd; | |
2329 | ||
2330 | while (*p) { | |
2331 | parent = *p; | |
2332 | nd = rb_entry(parent, struct sp_node, nd); | |
2333 | if (new->start < nd->start) | |
2334 | p = &(*p)->rb_left; | |
2335 | else if (new->end > nd->end) | |
2336 | p = &(*p)->rb_right; | |
2337 | else | |
2338 | BUG(); | |
2339 | } | |
2340 | rb_link_node(&new->nd, parent, p); | |
2341 | rb_insert_color(&new->nd, &sp->root); | |
140d5a49 | 2342 | pr_debug("inserting %lx-%lx: %d\n", new->start, new->end, |
45c4745a | 2343 | new->policy ? new->policy->mode : 0); |
1da177e4 LT |
2344 | } |
2345 | ||
2346 | /* Find shared policy intersecting idx */ | |
2347 | struct mempolicy * | |
2348 | mpol_shared_policy_lookup(struct shared_policy *sp, unsigned long idx) | |
2349 | { | |
2350 | struct mempolicy *pol = NULL; | |
2351 | struct sp_node *sn; | |
2352 | ||
2353 | if (!sp->root.rb_node) | |
2354 | return NULL; | |
4a8c7bb5 | 2355 | read_lock(&sp->lock); |
1da177e4 LT |
2356 | sn = sp_lookup(sp, idx, idx+1); |
2357 | if (sn) { | |
2358 | mpol_get(sn->policy); | |
2359 | pol = sn->policy; | |
2360 | } | |
4a8c7bb5 | 2361 | read_unlock(&sp->lock); |
1da177e4 LT |
2362 | return pol; |
2363 | } | |
2364 | ||
63f74ca2 KM |
2365 | static void sp_free(struct sp_node *n) |
2366 | { | |
2367 | mpol_put(n->policy); | |
2368 | kmem_cache_free(sn_cache, n); | |
2369 | } | |
2370 | ||
771fb4d8 LS |
2371 | /** |
2372 | * mpol_misplaced - check whether current page node is valid in policy | |
2373 | * | |
b46e14ac FF |
2374 | * @page: page to be checked |
2375 | * @vma: vm area where page mapped | |
2376 | * @addr: virtual address where page mapped | |
771fb4d8 LS |
2377 | * |
2378 | * Lookup current policy node id for vma,addr and "compare to" page's | |
5f076944 | 2379 | * node id. Policy determination "mimics" alloc_page_vma(). |
771fb4d8 | 2380 | * Called from fault path where we know the vma and faulting address. |
5f076944 | 2381 | * |
062db293 BW |
2382 | * Return: NUMA_NO_NODE if the page is in a node that is valid for this |
2383 | * policy, or a suitable node ID to allocate a replacement page from. | |
771fb4d8 LS |
2384 | */ |
2385 | int mpol_misplaced(struct page *page, struct vm_area_struct *vma, unsigned long addr) | |
2386 | { | |
2387 | struct mempolicy *pol; | |
c33d6c06 | 2388 | struct zoneref *z; |
771fb4d8 LS |
2389 | int curnid = page_to_nid(page); |
2390 | unsigned long pgoff; | |
90572890 PZ |
2391 | int thiscpu = raw_smp_processor_id(); |
2392 | int thisnid = cpu_to_node(thiscpu); | |
98fa15f3 | 2393 | int polnid = NUMA_NO_NODE; |
062db293 | 2394 | int ret = NUMA_NO_NODE; |
771fb4d8 | 2395 | |
dd6eecb9 | 2396 | pol = get_vma_policy(vma, addr); |
771fb4d8 LS |
2397 | if (!(pol->flags & MPOL_F_MOF)) |
2398 | goto out; | |
2399 | ||
2400 | switch (pol->mode) { | |
2401 | case MPOL_INTERLEAVE: | |
771fb4d8 LS |
2402 | pgoff = vma->vm_pgoff; |
2403 | pgoff += (addr - vma->vm_start) >> PAGE_SHIFT; | |
98c70baa | 2404 | polnid = offset_il_node(pol, pgoff); |
771fb4d8 LS |
2405 | break; |
2406 | ||
2407 | case MPOL_PREFERRED: | |
b27abacc DH |
2408 | if (node_isset(curnid, pol->nodes)) |
2409 | goto out; | |
269fbe72 | 2410 | polnid = first_node(pol->nodes); |
7858d7bc FT |
2411 | break; |
2412 | ||
2413 | case MPOL_LOCAL: | |
2414 | polnid = numa_node_id(); | |
771fb4d8 LS |
2415 | break; |
2416 | ||
2417 | case MPOL_BIND: | |
bda420b9 HY |
2418 | /* Optimize placement among multiple nodes via NUMA balancing */ |
2419 | if (pol->flags & MPOL_F_MORON) { | |
269fbe72 | 2420 | if (node_isset(thisnid, pol->nodes)) |
bda420b9 HY |
2421 | break; |
2422 | goto out; | |
2423 | } | |
b27abacc | 2424 | fallthrough; |
c33d6c06 | 2425 | |
b27abacc | 2426 | case MPOL_PREFERRED_MANY: |
771fb4d8 | 2427 | /* |
771fb4d8 LS |
2428 | * use current page if in policy nodemask, |
2429 | * else select nearest allowed node, if any. | |
2430 | * If no allowed nodes, use current [!misplaced]. | |
2431 | */ | |
269fbe72 | 2432 | if (node_isset(curnid, pol->nodes)) |
771fb4d8 | 2433 | goto out; |
c33d6c06 | 2434 | z = first_zones_zonelist( |
771fb4d8 LS |
2435 | node_zonelist(numa_node_id(), GFP_HIGHUSER), |
2436 | gfp_zone(GFP_HIGHUSER), | |
269fbe72 | 2437 | &pol->nodes); |
c1093b74 | 2438 | polnid = zone_to_nid(z->zone); |
771fb4d8 LS |
2439 | break; |
2440 | ||
2441 | default: | |
2442 | BUG(); | |
2443 | } | |
5606e387 MG |
2444 | |
2445 | /* Migrate the page towards the node whose CPU is referencing it */ | |
e42c8ff2 | 2446 | if (pol->flags & MPOL_F_MORON) { |
90572890 | 2447 | polnid = thisnid; |
5606e387 | 2448 | |
10f39042 | 2449 | if (!should_numa_migrate_memory(current, page, curnid, thiscpu)) |
de1c9ce6 | 2450 | goto out; |
e42c8ff2 MG |
2451 | } |
2452 | ||
771fb4d8 LS |
2453 | if (curnid != polnid) |
2454 | ret = polnid; | |
2455 | out: | |
2456 | mpol_cond_put(pol); | |
2457 | ||
2458 | return ret; | |
2459 | } | |
2460 | ||
c11600e4 DR |
2461 | /* |
2462 | * Drop the (possibly final) reference to task->mempolicy. It needs to be | |
2463 | * dropped after task->mempolicy is set to NULL so that any allocation done as | |
2464 | * part of its kmem_cache_free(), such as by KASAN, doesn't reference a freed | |
2465 | * policy. | |
2466 | */ | |
2467 | void mpol_put_task_policy(struct task_struct *task) | |
2468 | { | |
2469 | struct mempolicy *pol; | |
2470 | ||
2471 | task_lock(task); | |
2472 | pol = task->mempolicy; | |
2473 | task->mempolicy = NULL; | |
2474 | task_unlock(task); | |
2475 | mpol_put(pol); | |
2476 | } | |
2477 | ||
1da177e4 LT |
2478 | static void sp_delete(struct shared_policy *sp, struct sp_node *n) |
2479 | { | |
140d5a49 | 2480 | pr_debug("deleting %lx-l%lx\n", n->start, n->end); |
1da177e4 | 2481 | rb_erase(&n->nd, &sp->root); |
63f74ca2 | 2482 | sp_free(n); |
1da177e4 LT |
2483 | } |
2484 | ||
42288fe3 MG |
2485 | static void sp_node_init(struct sp_node *node, unsigned long start, |
2486 | unsigned long end, struct mempolicy *pol) | |
2487 | { | |
2488 | node->start = start; | |
2489 | node->end = end; | |
2490 | node->policy = pol; | |
2491 | } | |
2492 | ||
dbcb0f19 AB |
2493 | static struct sp_node *sp_alloc(unsigned long start, unsigned long end, |
2494 | struct mempolicy *pol) | |
1da177e4 | 2495 | { |
869833f2 KM |
2496 | struct sp_node *n; |
2497 | struct mempolicy *newpol; | |
1da177e4 | 2498 | |
869833f2 | 2499 | n = kmem_cache_alloc(sn_cache, GFP_KERNEL); |
1da177e4 LT |
2500 | if (!n) |
2501 | return NULL; | |
869833f2 KM |
2502 | |
2503 | newpol = mpol_dup(pol); | |
2504 | if (IS_ERR(newpol)) { | |
2505 | kmem_cache_free(sn_cache, n); | |
2506 | return NULL; | |
2507 | } | |
2508 | newpol->flags |= MPOL_F_SHARED; | |
42288fe3 | 2509 | sp_node_init(n, start, end, newpol); |
869833f2 | 2510 | |
1da177e4 LT |
2511 | return n; |
2512 | } | |
2513 | ||
2514 | /* Replace a policy range. */ | |
2515 | static int shared_policy_replace(struct shared_policy *sp, unsigned long start, | |
2516 | unsigned long end, struct sp_node *new) | |
2517 | { | |
b22d127a | 2518 | struct sp_node *n; |
42288fe3 MG |
2519 | struct sp_node *n_new = NULL; |
2520 | struct mempolicy *mpol_new = NULL; | |
b22d127a | 2521 | int ret = 0; |
1da177e4 | 2522 | |
42288fe3 | 2523 | restart: |
4a8c7bb5 | 2524 | write_lock(&sp->lock); |
1da177e4 LT |
2525 | n = sp_lookup(sp, start, end); |
2526 | /* Take care of old policies in the same range. */ | |
2527 | while (n && n->start < end) { | |
2528 | struct rb_node *next = rb_next(&n->nd); | |
2529 | if (n->start >= start) { | |
2530 | if (n->end <= end) | |
2531 | sp_delete(sp, n); | |
2532 | else | |
2533 | n->start = end; | |
2534 | } else { | |
2535 | /* Old policy spanning whole new range. */ | |
2536 | if (n->end > end) { | |
42288fe3 MG |
2537 | if (!n_new) |
2538 | goto alloc_new; | |
2539 | ||
2540 | *mpol_new = *n->policy; | |
2541 | atomic_set(&mpol_new->refcnt, 1); | |
7880639c | 2542 | sp_node_init(n_new, end, n->end, mpol_new); |
1da177e4 | 2543 | n->end = start; |
5ca39575 | 2544 | sp_insert(sp, n_new); |
42288fe3 MG |
2545 | n_new = NULL; |
2546 | mpol_new = NULL; | |
1da177e4 LT |
2547 | break; |
2548 | } else | |
2549 | n->end = start; | |
2550 | } | |
2551 | if (!next) | |
2552 | break; | |
2553 | n = rb_entry(next, struct sp_node, nd); | |
2554 | } | |
2555 | if (new) | |
2556 | sp_insert(sp, new); | |
4a8c7bb5 | 2557 | write_unlock(&sp->lock); |
42288fe3 MG |
2558 | ret = 0; |
2559 | ||
2560 | err_out: | |
2561 | if (mpol_new) | |
2562 | mpol_put(mpol_new); | |
2563 | if (n_new) | |
2564 | kmem_cache_free(sn_cache, n_new); | |
2565 | ||
b22d127a | 2566 | return ret; |
42288fe3 MG |
2567 | |
2568 | alloc_new: | |
4a8c7bb5 | 2569 | write_unlock(&sp->lock); |
42288fe3 MG |
2570 | ret = -ENOMEM; |
2571 | n_new = kmem_cache_alloc(sn_cache, GFP_KERNEL); | |
2572 | if (!n_new) | |
2573 | goto err_out; | |
2574 | mpol_new = kmem_cache_alloc(policy_cache, GFP_KERNEL); | |
2575 | if (!mpol_new) | |
2576 | goto err_out; | |
2577 | goto restart; | |
1da177e4 LT |
2578 | } |
2579 | ||
71fe804b LS |
2580 | /** |
2581 | * mpol_shared_policy_init - initialize shared policy for inode | |
2582 | * @sp: pointer to inode shared policy | |
2583 | * @mpol: struct mempolicy to install | |
2584 | * | |
2585 | * Install non-NULL @mpol in inode's shared policy rb-tree. | |
2586 | * On entry, the current task has a reference on a non-NULL @mpol. | |
2587 | * This must be released on exit. | |
4bfc4495 | 2588 | * This is called at get_inode() calls and we can use GFP_KERNEL. |
71fe804b LS |
2589 | */ |
2590 | void mpol_shared_policy_init(struct shared_policy *sp, struct mempolicy *mpol) | |
2591 | { | |
58568d2a MX |
2592 | int ret; |
2593 | ||
71fe804b | 2594 | sp->root = RB_ROOT; /* empty tree == default mempolicy */ |
4a8c7bb5 | 2595 | rwlock_init(&sp->lock); |
71fe804b LS |
2596 | |
2597 | if (mpol) { | |
2598 | struct vm_area_struct pvma; | |
2599 | struct mempolicy *new; | |
4bfc4495 | 2600 | NODEMASK_SCRATCH(scratch); |
71fe804b | 2601 | |
4bfc4495 | 2602 | if (!scratch) |
5c0c1654 | 2603 | goto put_mpol; |
71fe804b LS |
2604 | /* contextualize the tmpfs mount point mempolicy */ |
2605 | new = mpol_new(mpol->mode, mpol->flags, &mpol->w.user_nodemask); | |
15d77835 | 2606 | if (IS_ERR(new)) |
0cae3457 | 2607 | goto free_scratch; /* no valid nodemask intersection */ |
58568d2a MX |
2608 | |
2609 | task_lock(current); | |
4bfc4495 | 2610 | ret = mpol_set_nodemask(new, &mpol->w.user_nodemask, scratch); |
58568d2a | 2611 | task_unlock(current); |
15d77835 | 2612 | if (ret) |
5c0c1654 | 2613 | goto put_new; |
71fe804b LS |
2614 | |
2615 | /* Create pseudo-vma that contains just the policy */ | |
2c4541e2 | 2616 | vma_init(&pvma, NULL); |
71fe804b LS |
2617 | pvma.vm_end = TASK_SIZE; /* policy covers entire file */ |
2618 | mpol_set_shared_policy(sp, &pvma, new); /* adds ref */ | |
15d77835 | 2619 | |
5c0c1654 | 2620 | put_new: |
71fe804b | 2621 | mpol_put(new); /* drop initial ref */ |
0cae3457 | 2622 | free_scratch: |
4bfc4495 | 2623 | NODEMASK_SCRATCH_FREE(scratch); |
5c0c1654 LS |
2624 | put_mpol: |
2625 | mpol_put(mpol); /* drop our incoming ref on sb mpol */ | |
7339ff83 RH |
2626 | } |
2627 | } | |
2628 | ||
1da177e4 LT |
2629 | int mpol_set_shared_policy(struct shared_policy *info, |
2630 | struct vm_area_struct *vma, struct mempolicy *npol) | |
2631 | { | |
2632 | int err; | |
2633 | struct sp_node *new = NULL; | |
2634 | unsigned long sz = vma_pages(vma); | |
2635 | ||
028fec41 | 2636 | pr_debug("set_shared_policy %lx sz %lu %d %d %lx\n", |
1da177e4 | 2637 | vma->vm_pgoff, |
45c4745a | 2638 | sz, npol ? npol->mode : -1, |
028fec41 | 2639 | npol ? npol->flags : -1, |
269fbe72 | 2640 | npol ? nodes_addr(npol->nodes)[0] : NUMA_NO_NODE); |
1da177e4 LT |
2641 | |
2642 | if (npol) { | |
2643 | new = sp_alloc(vma->vm_pgoff, vma->vm_pgoff + sz, npol); | |
2644 | if (!new) | |
2645 | return -ENOMEM; | |
2646 | } | |
2647 | err = shared_policy_replace(info, vma->vm_pgoff, vma->vm_pgoff+sz, new); | |
2648 | if (err && new) | |
63f74ca2 | 2649 | sp_free(new); |
1da177e4 LT |
2650 | return err; |
2651 | } | |
2652 | ||
2653 | /* Free a backing policy store on inode delete. */ | |
2654 | void mpol_free_shared_policy(struct shared_policy *p) | |
2655 | { | |
2656 | struct sp_node *n; | |
2657 | struct rb_node *next; | |
2658 | ||
2659 | if (!p->root.rb_node) | |
2660 | return; | |
4a8c7bb5 | 2661 | write_lock(&p->lock); |
1da177e4 LT |
2662 | next = rb_first(&p->root); |
2663 | while (next) { | |
2664 | n = rb_entry(next, struct sp_node, nd); | |
2665 | next = rb_next(&n->nd); | |
63f74ca2 | 2666 | sp_delete(p, n); |
1da177e4 | 2667 | } |
4a8c7bb5 | 2668 | write_unlock(&p->lock); |
1da177e4 LT |
2669 | } |
2670 | ||
1a687c2e | 2671 | #ifdef CONFIG_NUMA_BALANCING |
c297663c | 2672 | static int __initdata numabalancing_override; |
1a687c2e MG |
2673 | |
2674 | static void __init check_numabalancing_enable(void) | |
2675 | { | |
2676 | bool numabalancing_default = false; | |
2677 | ||
2678 | if (IS_ENABLED(CONFIG_NUMA_BALANCING_DEFAULT_ENABLED)) | |
2679 | numabalancing_default = true; | |
2680 | ||
c297663c MG |
2681 | /* Parsed by setup_numabalancing. override == 1 enables, -1 disables */ |
2682 | if (numabalancing_override) | |
2683 | set_numabalancing_state(numabalancing_override == 1); | |
2684 | ||
b0dc2b9b | 2685 | if (num_online_nodes() > 1 && !numabalancing_override) { |
756a025f | 2686 | pr_info("%s automatic NUMA balancing. Configure with numa_balancing= or the kernel.numa_balancing sysctl\n", |
c297663c | 2687 | numabalancing_default ? "Enabling" : "Disabling"); |
1a687c2e MG |
2688 | set_numabalancing_state(numabalancing_default); |
2689 | } | |
2690 | } | |
2691 | ||
2692 | static int __init setup_numabalancing(char *str) | |
2693 | { | |
2694 | int ret = 0; | |
2695 | if (!str) | |
2696 | goto out; | |
1a687c2e MG |
2697 | |
2698 | if (!strcmp(str, "enable")) { | |
c297663c | 2699 | numabalancing_override = 1; |
1a687c2e MG |
2700 | ret = 1; |
2701 | } else if (!strcmp(str, "disable")) { | |
c297663c | 2702 | numabalancing_override = -1; |
1a687c2e MG |
2703 | ret = 1; |
2704 | } | |
2705 | out: | |
2706 | if (!ret) | |
4a404bea | 2707 | pr_warn("Unable to parse numa_balancing=\n"); |
1a687c2e MG |
2708 | |
2709 | return ret; | |
2710 | } | |
2711 | __setup("numa_balancing=", setup_numabalancing); | |
2712 | #else | |
2713 | static inline void __init check_numabalancing_enable(void) | |
2714 | { | |
2715 | } | |
2716 | #endif /* CONFIG_NUMA_BALANCING */ | |
2717 | ||
1da177e4 LT |
2718 | /* assumes fs == KERNEL_DS */ |
2719 | void __init numa_policy_init(void) | |
2720 | { | |
b71636e2 PM |
2721 | nodemask_t interleave_nodes; |
2722 | unsigned long largest = 0; | |
2723 | int nid, prefer = 0; | |
2724 | ||
1da177e4 LT |
2725 | policy_cache = kmem_cache_create("numa_policy", |
2726 | sizeof(struct mempolicy), | |
20c2df83 | 2727 | 0, SLAB_PANIC, NULL); |
1da177e4 LT |
2728 | |
2729 | sn_cache = kmem_cache_create("shared_policy_node", | |
2730 | sizeof(struct sp_node), | |
20c2df83 | 2731 | 0, SLAB_PANIC, NULL); |
1da177e4 | 2732 | |
5606e387 MG |
2733 | for_each_node(nid) { |
2734 | preferred_node_policy[nid] = (struct mempolicy) { | |
2735 | .refcnt = ATOMIC_INIT(1), | |
2736 | .mode = MPOL_PREFERRED, | |
2737 | .flags = MPOL_F_MOF | MPOL_F_MORON, | |
269fbe72 | 2738 | .nodes = nodemask_of_node(nid), |
5606e387 MG |
2739 | }; |
2740 | } | |
2741 | ||
b71636e2 PM |
2742 | /* |
2743 | * Set interleaving policy for system init. Interleaving is only | |
2744 | * enabled across suitably sized nodes (default is >= 16MB), or | |
2745 | * fall back to the largest node if they're all smaller. | |
2746 | */ | |
2747 | nodes_clear(interleave_nodes); | |
01f13bd6 | 2748 | for_each_node_state(nid, N_MEMORY) { |
b71636e2 PM |
2749 | unsigned long total_pages = node_present_pages(nid); |
2750 | ||
2751 | /* Preserve the largest node */ | |
2752 | if (largest < total_pages) { | |
2753 | largest = total_pages; | |
2754 | prefer = nid; | |
2755 | } | |
2756 | ||
2757 | /* Interleave this node? */ | |
2758 | if ((total_pages << PAGE_SHIFT) >= (16 << 20)) | |
2759 | node_set(nid, interleave_nodes); | |
2760 | } | |
2761 | ||
2762 | /* All too small, use the largest */ | |
2763 | if (unlikely(nodes_empty(interleave_nodes))) | |
2764 | node_set(prefer, interleave_nodes); | |
1da177e4 | 2765 | |
028fec41 | 2766 | if (do_set_mempolicy(MPOL_INTERLEAVE, 0, &interleave_nodes)) |
b1de0d13 | 2767 | pr_err("%s: interleaving failed\n", __func__); |
1a687c2e MG |
2768 | |
2769 | check_numabalancing_enable(); | |
1da177e4 LT |
2770 | } |
2771 | ||
8bccd85f | 2772 | /* Reset policy of current process to default */ |
1da177e4 LT |
2773 | void numa_default_policy(void) |
2774 | { | |
028fec41 | 2775 | do_set_mempolicy(MPOL_DEFAULT, 0, NULL); |
1da177e4 | 2776 | } |
68860ec1 | 2777 | |
095f1fc4 LS |
2778 | /* |
2779 | * Parse and format mempolicy from/to strings | |
2780 | */ | |
2781 | ||
345ace9c LS |
2782 | static const char * const policy_modes[] = |
2783 | { | |
2784 | [MPOL_DEFAULT] = "default", | |
2785 | [MPOL_PREFERRED] = "prefer", | |
2786 | [MPOL_BIND] = "bind", | |
2787 | [MPOL_INTERLEAVE] = "interleave", | |
d3a71033 | 2788 | [MPOL_LOCAL] = "local", |
b27abacc | 2789 | [MPOL_PREFERRED_MANY] = "prefer (many)", |
345ace9c | 2790 | }; |
1a75a6c8 | 2791 | |
095f1fc4 LS |
2792 | |
2793 | #ifdef CONFIG_TMPFS | |
2794 | /** | |
f2a07f40 | 2795 | * mpol_parse_str - parse string to mempolicy, for tmpfs mpol mount option. |
095f1fc4 | 2796 | * @str: string containing mempolicy to parse |
71fe804b | 2797 | * @mpol: pointer to struct mempolicy pointer, returned on success. |
095f1fc4 LS |
2798 | * |
2799 | * Format of input: | |
2800 | * <mode>[=<flags>][:<nodelist>] | |
2801 | * | |
71fe804b | 2802 | * On success, returns 0, else 1 |
095f1fc4 | 2803 | */ |
a7a88b23 | 2804 | int mpol_parse_str(char *str, struct mempolicy **mpol) |
095f1fc4 | 2805 | { |
71fe804b | 2806 | struct mempolicy *new = NULL; |
f2a07f40 | 2807 | unsigned short mode_flags; |
71fe804b | 2808 | nodemask_t nodes; |
095f1fc4 LS |
2809 | char *nodelist = strchr(str, ':'); |
2810 | char *flags = strchr(str, '='); | |
dedf2c73 | 2811 | int err = 1, mode; |
095f1fc4 | 2812 | |
c7a91bc7 DC |
2813 | if (flags) |
2814 | *flags++ = '\0'; /* terminate mode string */ | |
2815 | ||
095f1fc4 LS |
2816 | if (nodelist) { |
2817 | /* NUL-terminate mode or flags string */ | |
2818 | *nodelist++ = '\0'; | |
71fe804b | 2819 | if (nodelist_parse(nodelist, nodes)) |
095f1fc4 | 2820 | goto out; |
01f13bd6 | 2821 | if (!nodes_subset(nodes, node_states[N_MEMORY])) |
095f1fc4 | 2822 | goto out; |
71fe804b LS |
2823 | } else |
2824 | nodes_clear(nodes); | |
2825 | ||
dedf2c73 | 2826 | mode = match_string(policy_modes, MPOL_MAX, str); |
2827 | if (mode < 0) | |
095f1fc4 LS |
2828 | goto out; |
2829 | ||
71fe804b | 2830 | switch (mode) { |
095f1fc4 | 2831 | case MPOL_PREFERRED: |
71fe804b | 2832 | /* |
aa9f7d51 RD |
2833 | * Insist on a nodelist of one node only, although later |
2834 | * we use first_node(nodes) to grab a single node, so here | |
2835 | * nodelist (or nodes) cannot be empty. | |
71fe804b | 2836 | */ |
095f1fc4 LS |
2837 | if (nodelist) { |
2838 | char *rest = nodelist; | |
2839 | while (isdigit(*rest)) | |
2840 | rest++; | |
926f2ae0 KM |
2841 | if (*rest) |
2842 | goto out; | |
aa9f7d51 RD |
2843 | if (nodes_empty(nodes)) |
2844 | goto out; | |
095f1fc4 LS |
2845 | } |
2846 | break; | |
095f1fc4 LS |
2847 | case MPOL_INTERLEAVE: |
2848 | /* | |
2849 | * Default to online nodes with memory if no nodelist | |
2850 | */ | |
2851 | if (!nodelist) | |
01f13bd6 | 2852 | nodes = node_states[N_MEMORY]; |
3f226aa1 | 2853 | break; |
71fe804b | 2854 | case MPOL_LOCAL: |
3f226aa1 | 2855 | /* |
71fe804b | 2856 | * Don't allow a nodelist; mpol_new() checks flags |
3f226aa1 | 2857 | */ |
71fe804b | 2858 | if (nodelist) |
3f226aa1 | 2859 | goto out; |
3f226aa1 | 2860 | break; |
413b43de RT |
2861 | case MPOL_DEFAULT: |
2862 | /* | |
2863 | * Insist on a empty nodelist | |
2864 | */ | |
2865 | if (!nodelist) | |
2866 | err = 0; | |
2867 | goto out; | |
b27abacc | 2868 | case MPOL_PREFERRED_MANY: |
d69b2e63 KM |
2869 | case MPOL_BIND: |
2870 | /* | |
2871 | * Insist on a nodelist | |
2872 | */ | |
2873 | if (!nodelist) | |
2874 | goto out; | |
095f1fc4 LS |
2875 | } |
2876 | ||
71fe804b | 2877 | mode_flags = 0; |
095f1fc4 LS |
2878 | if (flags) { |
2879 | /* | |
2880 | * Currently, we only support two mutually exclusive | |
2881 | * mode flags. | |
2882 | */ | |
2883 | if (!strcmp(flags, "static")) | |
71fe804b | 2884 | mode_flags |= MPOL_F_STATIC_NODES; |
095f1fc4 | 2885 | else if (!strcmp(flags, "relative")) |
71fe804b | 2886 | mode_flags |= MPOL_F_RELATIVE_NODES; |
095f1fc4 | 2887 | else |
926f2ae0 | 2888 | goto out; |
095f1fc4 | 2889 | } |
71fe804b LS |
2890 | |
2891 | new = mpol_new(mode, mode_flags, &nodes); | |
2892 | if (IS_ERR(new)) | |
926f2ae0 KM |
2893 | goto out; |
2894 | ||
f2a07f40 HD |
2895 | /* |
2896 | * Save nodes for mpol_to_str() to show the tmpfs mount options | |
2897 | * for /proc/mounts, /proc/pid/mounts and /proc/pid/mountinfo. | |
2898 | */ | |
269fbe72 BW |
2899 | if (mode != MPOL_PREFERRED) { |
2900 | new->nodes = nodes; | |
2901 | } else if (nodelist) { | |
2902 | nodes_clear(new->nodes); | |
2903 | node_set(first_node(nodes), new->nodes); | |
2904 | } else { | |
7858d7bc | 2905 | new->mode = MPOL_LOCAL; |
269fbe72 | 2906 | } |
f2a07f40 HD |
2907 | |
2908 | /* | |
2909 | * Save nodes for contextualization: this will be used to "clone" | |
2910 | * the mempolicy in a specific context [cpuset] at a later time. | |
2911 | */ | |
2912 | new->w.user_nodemask = nodes; | |
2913 | ||
926f2ae0 | 2914 | err = 0; |
71fe804b | 2915 | |
095f1fc4 LS |
2916 | out: |
2917 | /* Restore string for error message */ | |
2918 | if (nodelist) | |
2919 | *--nodelist = ':'; | |
2920 | if (flags) | |
2921 | *--flags = '='; | |
71fe804b LS |
2922 | if (!err) |
2923 | *mpol = new; | |
095f1fc4 LS |
2924 | return err; |
2925 | } | |
2926 | #endif /* CONFIG_TMPFS */ | |
2927 | ||
71fe804b LS |
2928 | /** |
2929 | * mpol_to_str - format a mempolicy structure for printing | |
2930 | * @buffer: to contain formatted mempolicy string | |
2931 | * @maxlen: length of @buffer | |
2932 | * @pol: pointer to mempolicy to be formatted | |
71fe804b | 2933 | * |
948927ee DR |
2934 | * Convert @pol into a string. If @buffer is too short, truncate the string. |
2935 | * Recommend a @maxlen of at least 32 for the longest mode, "interleave", the | |
2936 | * longest flag, "relative", and to display at least a few node ids. | |
1a75a6c8 | 2937 | */ |
948927ee | 2938 | void mpol_to_str(char *buffer, int maxlen, struct mempolicy *pol) |
1a75a6c8 CL |
2939 | { |
2940 | char *p = buffer; | |
948927ee DR |
2941 | nodemask_t nodes = NODE_MASK_NONE; |
2942 | unsigned short mode = MPOL_DEFAULT; | |
2943 | unsigned short flags = 0; | |
2291990a | 2944 | |
8790c71a | 2945 | if (pol && pol != &default_policy && !(pol->flags & MPOL_F_MORON)) { |
bea904d5 | 2946 | mode = pol->mode; |
948927ee DR |
2947 | flags = pol->flags; |
2948 | } | |
bea904d5 | 2949 | |
1a75a6c8 CL |
2950 | switch (mode) { |
2951 | case MPOL_DEFAULT: | |
7858d7bc | 2952 | case MPOL_LOCAL: |
1a75a6c8 | 2953 | break; |
1a75a6c8 | 2954 | case MPOL_PREFERRED: |
b27abacc | 2955 | case MPOL_PREFERRED_MANY: |
1a75a6c8 | 2956 | case MPOL_BIND: |
1a75a6c8 | 2957 | case MPOL_INTERLEAVE: |
269fbe72 | 2958 | nodes = pol->nodes; |
1a75a6c8 | 2959 | break; |
1a75a6c8 | 2960 | default: |
948927ee DR |
2961 | WARN_ON_ONCE(1); |
2962 | snprintf(p, maxlen, "unknown"); | |
2963 | return; | |
1a75a6c8 CL |
2964 | } |
2965 | ||
b7a9f420 | 2966 | p += snprintf(p, maxlen, "%s", policy_modes[mode]); |
1a75a6c8 | 2967 | |
fc36b8d3 | 2968 | if (flags & MPOL_MODE_FLAGS) { |
948927ee | 2969 | p += snprintf(p, buffer + maxlen - p, "="); |
f5b087b5 | 2970 | |
2291990a LS |
2971 | /* |
2972 | * Currently, the only defined flags are mutually exclusive | |
2973 | */ | |
f5b087b5 | 2974 | if (flags & MPOL_F_STATIC_NODES) |
2291990a LS |
2975 | p += snprintf(p, buffer + maxlen - p, "static"); |
2976 | else if (flags & MPOL_F_RELATIVE_NODES) | |
2977 | p += snprintf(p, buffer + maxlen - p, "relative"); | |
f5b087b5 DR |
2978 | } |
2979 | ||
9e763e0f TH |
2980 | if (!nodes_empty(nodes)) |
2981 | p += scnprintf(p, buffer + maxlen - p, ":%*pbl", | |
2982 | nodemask_pr_args(&nodes)); | |
1a75a6c8 | 2983 | } |
20b51af1 HY |
2984 | |
2985 | bool numa_demotion_enabled = false; | |
2986 | ||
2987 | #ifdef CONFIG_SYSFS | |
2988 | static ssize_t numa_demotion_enabled_show(struct kobject *kobj, | |
2989 | struct kobj_attribute *attr, char *buf) | |
2990 | { | |
2991 | return sysfs_emit(buf, "%s\n", | |
2992 | numa_demotion_enabled? "true" : "false"); | |
2993 | } | |
2994 | ||
2995 | static ssize_t numa_demotion_enabled_store(struct kobject *kobj, | |
2996 | struct kobj_attribute *attr, | |
2997 | const char *buf, size_t count) | |
2998 | { | |
2999 | if (!strncmp(buf, "true", 4) || !strncmp(buf, "1", 1)) | |
3000 | numa_demotion_enabled = true; | |
3001 | else if (!strncmp(buf, "false", 5) || !strncmp(buf, "0", 1)) | |
3002 | numa_demotion_enabled = false; | |
3003 | else | |
3004 | return -EINVAL; | |
3005 | ||
3006 | return count; | |
3007 | } | |
3008 | ||
3009 | static struct kobj_attribute numa_demotion_enabled_attr = | |
3010 | __ATTR(demotion_enabled, 0644, numa_demotion_enabled_show, | |
3011 | numa_demotion_enabled_store); | |
3012 | ||
3013 | static struct attribute *numa_attrs[] = { | |
3014 | &numa_demotion_enabled_attr.attr, | |
3015 | NULL, | |
3016 | }; | |
3017 | ||
3018 | static const struct attribute_group numa_attr_group = { | |
3019 | .attrs = numa_attrs, | |
3020 | }; | |
3021 | ||
3022 | static int __init numa_init_sysfs(void) | |
3023 | { | |
3024 | int err; | |
3025 | struct kobject *numa_kobj; | |
3026 | ||
3027 | numa_kobj = kobject_create_and_add("numa", mm_kobj); | |
3028 | if (!numa_kobj) { | |
3029 | pr_err("failed to create numa kobject\n"); | |
3030 | return -ENOMEM; | |
3031 | } | |
3032 | err = sysfs_create_group(numa_kobj, &numa_attr_group); | |
3033 | if (err) { | |
3034 | pr_err("failed to register numa group\n"); | |
3035 | goto delete_obj; | |
3036 | } | |
3037 | return 0; | |
3038 | ||
3039 | delete_obj: | |
3040 | kobject_put(numa_kobj); | |
3041 | return err; | |
3042 | } | |
3043 | subsys_initcall(numa_init_sysfs); | |
3044 | #endif |