blob: 1850d0aef4ac3aba3abc99caf9b479c75319e368 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * Simple NUMA memory policy for the Linux kernel.
3 *
4 * Copyright 2003,2004 Andi Kleen, SuSE Labs.
Christoph Lameter8bccd852005-10-29 18:16:59 -07005 * (C) Copyright 2005 Christoph Lameter, Silicon Graphics, Inc.
Linus Torvalds1da177e2005-04-16 15:20:36 -07006 * Subject to the GNU Public License, version 2.
7 *
8 * NUMA policy allows the user to give hints in which node(s) memory should
9 * be allocated.
10 *
11 * Support four policies per VMA and per process:
12 *
13 * The VMA policy has priority over the process policy for a page fault.
14 *
15 * interleave Allocate memory interleaved over a set of nodes,
16 * with normal fallback if it fails.
17 * For VMA based allocations this interleaves based on the
18 * offset into the backing object or offset into the mapping
19 * for anonymous memory. For process policy an process counter
20 * is used.
Christoph Lameter8bccd852005-10-29 18:16:59 -070021 *
Linus Torvalds1da177e2005-04-16 15:20:36 -070022 * bind Only allocate memory on a specific set of nodes,
23 * no fallback.
Christoph Lameter8bccd852005-10-29 18:16:59 -070024 * 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 *
Linus Torvalds1da177e2005-04-16 15:20:36 -070028 * preferred Try a specific node first before normal fallback.
29 * As a special case node -1 here means do the allocation
30 * on the local CPU. This is normally identical to default,
31 * but useful to set in a VMA when you have a non default
32 * process policy.
Christoph Lameter8bccd852005-10-29 18:16:59 -070033 *
Linus Torvalds1da177e2005-04-16 15:20:36 -070034 * default Allocate on the local node first, or when on a VMA
35 * use the process policy. This is what Linux always did
36 * in a NUMA aware kernel and still does by, ahem, default.
37 *
38 * The process policy is applied for most non interrupt memory allocations
39 * in that process' context. Interrupts ignore the policies and always
40 * try to allocate on the local CPU. The VMA policy is only applied for memory
41 * allocations for a VMA in the VM.
42 *
43 * Currently there are a few corner cases in swapping where the policy
44 * is not applied, but the majority should be handled. When process policy
45 * is used it is not remembered over swap outs/swap ins.
46 *
47 * Only the highest zone in the zone hierarchy gets policied. Allocations
48 * requesting a lower zone just use default policy. This implies that
49 * on systems with highmem kernel lowmem allocation don't get policied.
50 * Same with GFP_DMA allocations.
51 *
52 * For shmfs/tmpfs/hugetlbfs shared memory the policy is shared between
53 * all users and remembered even when nobody has memory mapped.
54 */
55
56/* Notebook:
57 fix mmap readahead to honour policy and enable policy for any page cache
58 object
59 statistics for bigpages
60 global policy for page cache? currently it uses process policy. Requires
61 first item above.
62 handle mremap for shared memory (currently ignored for the policy)
63 grows down?
64 make bind policy root only? It can trigger oom much faster and the
65 kernel is not always grateful with that.
66 could replace all the switch()es with a mempolicy_ops structure.
67*/
68
69#include <linux/mempolicy.h>
70#include <linux/mm.h>
71#include <linux/highmem.h>
72#include <linux/hugetlb.h>
73#include <linux/kernel.h>
74#include <linux/sched.h>
75#include <linux/mm.h>
76#include <linux/nodemask.h>
77#include <linux/cpuset.h>
78#include <linux/gfp.h>
79#include <linux/slab.h>
80#include <linux/string.h>
81#include <linux/module.h>
82#include <linux/interrupt.h>
83#include <linux/init.h>
84#include <linux/compat.h>
85#include <linux/mempolicy.h>
Christoph Lameterdc9aa5b2006-01-08 01:00:50 -080086#include <linux/swap.h>
Christoph Lameter1a75a6c2006-01-08 01:01:02 -080087#include <linux/seq_file.h>
88#include <linux/proc_fs.h>
Christoph Lameterdc9aa5b2006-01-08 01:00:50 -080089
Linus Torvalds1da177e2005-04-16 15:20:36 -070090#include <asm/tlbflush.h>
91#include <asm/uaccess.h>
92
Christoph Lameter38e35862006-01-08 01:01:01 -080093/* Internal flags */
Christoph Lameterdc9aa5b2006-01-08 01:00:50 -080094#define MPOL_MF_DISCONTIG_OK (MPOL_MF_INTERNAL << 0) /* Skip checks for continuous vmas */
Christoph Lameter38e35862006-01-08 01:01:01 -080095#define MPOL_MF_INVERT (MPOL_MF_INTERNAL << 1) /* Invert check for nodemask */
Christoph Lameter1a75a6c2006-01-08 01:01:02 -080096#define MPOL_MF_STATS (MPOL_MF_INTERNAL << 2) /* Gather statistics */
Christoph Lameterdc9aa5b2006-01-08 01:00:50 -080097
Linus Torvalds1da177e2005-04-16 15:20:36 -070098static kmem_cache_t *policy_cache;
99static kmem_cache_t *sn_cache;
100
101#define PDprintk(fmt...)
102
103/* Highest zone. An specific allocation for a zone below that is not
104 policied. */
Christoph Lameter4be38e32006-01-06 00:11:17 -0800105int policy_zone = ZONE_DMA;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700106
Andi Kleend42c6992005-07-06 19:56:03 +0200107struct mempolicy default_policy = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700108 .refcnt = ATOMIC_INIT(1), /* never free it */
109 .policy = MPOL_DEFAULT,
110};
111
Linus Torvalds1da177e2005-04-16 15:20:36 -0700112/* Do sanity checking on a policy */
Andi Kleendfcd3c02005-10-29 18:15:48 -0700113static int mpol_check_policy(int mode, nodemask_t *nodes)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700114{
Andi Kleendfcd3c02005-10-29 18:15:48 -0700115 int empty = nodes_empty(*nodes);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700116
117 switch (mode) {
118 case MPOL_DEFAULT:
119 if (!empty)
120 return -EINVAL;
121 break;
122 case MPOL_BIND:
123 case MPOL_INTERLEAVE:
124 /* Preferred will only use the first bit, but allow
125 more for now. */
126 if (empty)
127 return -EINVAL;
128 break;
129 }
Andi Kleendfcd3c02005-10-29 18:15:48 -0700130 return nodes_subset(*nodes, node_online_map) ? 0 : -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700131}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700132/* Generate a custom zonelist for the BIND policy. */
Andi Kleendfcd3c02005-10-29 18:15:48 -0700133static struct zonelist *bind_zonelist(nodemask_t *nodes)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700134{
135 struct zonelist *zl;
136 int num, max, nd;
137
Andi Kleendfcd3c02005-10-29 18:15:48 -0700138 max = 1 + MAX_NR_ZONES * nodes_weight(*nodes);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700139 zl = kmalloc(sizeof(void *) * max, GFP_KERNEL);
140 if (!zl)
141 return NULL;
142 num = 0;
Christoph Lameter4be38e32006-01-06 00:11:17 -0800143 for_each_node_mask(nd, *nodes)
144 zl->zones[num++] = &NODE_DATA(nd)->node_zones[policy_zone];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700145 zl->zones[num] = NULL;
146 return zl;
147}
148
149/* Create a new policy */
Andi Kleendfcd3c02005-10-29 18:15:48 -0700150static struct mempolicy *mpol_new(int mode, nodemask_t *nodes)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700151{
152 struct mempolicy *policy;
153
Andi Kleendfcd3c02005-10-29 18:15:48 -0700154 PDprintk("setting mode %d nodes[0] %lx\n", mode, nodes_addr(*nodes)[0]);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700155 if (mode == MPOL_DEFAULT)
156 return NULL;
157 policy = kmem_cache_alloc(policy_cache, GFP_KERNEL);
158 if (!policy)
159 return ERR_PTR(-ENOMEM);
160 atomic_set(&policy->refcnt, 1);
161 switch (mode) {
162 case MPOL_INTERLEAVE:
Andi Kleendfcd3c02005-10-29 18:15:48 -0700163 policy->v.nodes = *nodes;
Andi Kleen8f493d72006-01-03 00:07:28 +0100164 if (nodes_weight(*nodes) == 0) {
165 kmem_cache_free(policy_cache, policy);
166 return ERR_PTR(-EINVAL);
167 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700168 break;
169 case MPOL_PREFERRED:
Andi Kleendfcd3c02005-10-29 18:15:48 -0700170 policy->v.preferred_node = first_node(*nodes);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700171 if (policy->v.preferred_node >= MAX_NUMNODES)
172 policy->v.preferred_node = -1;
173 break;
174 case MPOL_BIND:
175 policy->v.zonelist = bind_zonelist(nodes);
176 if (policy->v.zonelist == NULL) {
177 kmem_cache_free(policy_cache, policy);
178 return ERR_PTR(-ENOMEM);
179 }
180 break;
181 }
182 policy->policy = mode;
Paul Jackson74cb2152006-01-08 01:01:56 -0800183 policy->cpuset_mems_allowed = cpuset_mems_allowed(current);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700184 return policy;
185}
186
Christoph Lameter1a75a6c2006-01-08 01:01:02 -0800187static void gather_stats(struct page *, void *);
Christoph Lameter6ce3c4c2006-01-08 01:01:04 -0800188static void migrate_page_add(struct vm_area_struct *vma,
189 struct page *page, struct list_head *pagelist, unsigned long flags);
Christoph Lameter1a75a6c2006-01-08 01:01:02 -0800190
Christoph Lameter38e35862006-01-08 01:01:01 -0800191/* Scan through pages checking if pages follow certain conditions. */
Nick Pigginb5810032005-10-29 18:16:12 -0700192static int check_pte_range(struct vm_area_struct *vma, pmd_t *pmd,
Christoph Lameterdc9aa5b2006-01-08 01:00:50 -0800193 unsigned long addr, unsigned long end,
194 const nodemask_t *nodes, unsigned long flags,
Christoph Lameter38e35862006-01-08 01:01:01 -0800195 void *private)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700196{
Hugh Dickins91612e02005-06-21 17:15:07 -0700197 pte_t *orig_pte;
198 pte_t *pte;
Hugh Dickins705e87c2005-10-29 18:16:27 -0700199 spinlock_t *ptl;
Hugh Dickins941150a2005-06-21 17:15:06 -0700200
Hugh Dickins705e87c2005-10-29 18:16:27 -0700201 orig_pte = pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
Hugh Dickins91612e02005-06-21 17:15:07 -0700202 do {
Linus Torvalds6aab3412005-11-28 14:34:23 -0800203 struct page *page;
Hugh Dickins91612e02005-06-21 17:15:07 -0700204 unsigned int nid;
205
206 if (!pte_present(*pte))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700207 continue;
Linus Torvalds6aab3412005-11-28 14:34:23 -0800208 page = vm_normal_page(vma, addr, *pte);
209 if (!page)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700210 continue;
Linus Torvalds6aab3412005-11-28 14:34:23 -0800211 nid = page_to_nid(page);
Christoph Lameter38e35862006-01-08 01:01:01 -0800212 if (node_isset(nid, *nodes) == !!(flags & MPOL_MF_INVERT))
213 continue;
214
Christoph Lameter1a75a6c2006-01-08 01:01:02 -0800215 if (flags & MPOL_MF_STATS)
216 gather_stats(page, private);
Christoph Lameter132beac2006-01-08 01:01:02 -0800217 else if (flags & (MPOL_MF_MOVE | MPOL_MF_MOVE_ALL)) {
218 spin_unlock(ptl);
Christoph Lameter38e35862006-01-08 01:01:01 -0800219 migrate_page_add(vma, page, private, flags);
Christoph Lameter132beac2006-01-08 01:01:02 -0800220 spin_lock(ptl);
221 }
Christoph Lameter38e35862006-01-08 01:01:01 -0800222 else
223 break;
Hugh Dickins91612e02005-06-21 17:15:07 -0700224 } while (pte++, addr += PAGE_SIZE, addr != end);
Hugh Dickins705e87c2005-10-29 18:16:27 -0700225 pte_unmap_unlock(orig_pte, ptl);
Hugh Dickins91612e02005-06-21 17:15:07 -0700226 return addr != end;
227}
228
Nick Pigginb5810032005-10-29 18:16:12 -0700229static inline int check_pmd_range(struct vm_area_struct *vma, pud_t *pud,
Christoph Lameterdc9aa5b2006-01-08 01:00:50 -0800230 unsigned long addr, unsigned long end,
231 const nodemask_t *nodes, unsigned long flags,
Christoph Lameter38e35862006-01-08 01:01:01 -0800232 void *private)
Hugh Dickins91612e02005-06-21 17:15:07 -0700233{
234 pmd_t *pmd;
235 unsigned long next;
236
237 pmd = pmd_offset(pud, addr);
238 do {
239 next = pmd_addr_end(addr, end);
240 if (pmd_none_or_clear_bad(pmd))
241 continue;
Christoph Lameterdc9aa5b2006-01-08 01:00:50 -0800242 if (check_pte_range(vma, pmd, addr, next, nodes,
Christoph Lameter38e35862006-01-08 01:01:01 -0800243 flags, private))
Hugh Dickins91612e02005-06-21 17:15:07 -0700244 return -EIO;
245 } while (pmd++, addr = next, addr != end);
246 return 0;
247}
248
Nick Pigginb5810032005-10-29 18:16:12 -0700249static inline int check_pud_range(struct vm_area_struct *vma, pgd_t *pgd,
Christoph Lameterdc9aa5b2006-01-08 01:00:50 -0800250 unsigned long addr, unsigned long end,
251 const nodemask_t *nodes, unsigned long flags,
Christoph Lameter38e35862006-01-08 01:01:01 -0800252 void *private)
Hugh Dickins91612e02005-06-21 17:15:07 -0700253{
254 pud_t *pud;
255 unsigned long next;
256
257 pud = pud_offset(pgd, addr);
258 do {
259 next = pud_addr_end(addr, end);
260 if (pud_none_or_clear_bad(pud))
261 continue;
Christoph Lameterdc9aa5b2006-01-08 01:00:50 -0800262 if (check_pmd_range(vma, pud, addr, next, nodes,
Christoph Lameter38e35862006-01-08 01:01:01 -0800263 flags, private))
Hugh Dickins91612e02005-06-21 17:15:07 -0700264 return -EIO;
265 } while (pud++, addr = next, addr != end);
266 return 0;
267}
268
Nick Pigginb5810032005-10-29 18:16:12 -0700269static inline int check_pgd_range(struct vm_area_struct *vma,
Christoph Lameterdc9aa5b2006-01-08 01:00:50 -0800270 unsigned long addr, unsigned long end,
271 const nodemask_t *nodes, unsigned long flags,
Christoph Lameter38e35862006-01-08 01:01:01 -0800272 void *private)
Hugh Dickins91612e02005-06-21 17:15:07 -0700273{
274 pgd_t *pgd;
275 unsigned long next;
276
Nick Pigginb5810032005-10-29 18:16:12 -0700277 pgd = pgd_offset(vma->vm_mm, addr);
Hugh Dickins91612e02005-06-21 17:15:07 -0700278 do {
279 next = pgd_addr_end(addr, end);
280 if (pgd_none_or_clear_bad(pgd))
281 continue;
Christoph Lameterdc9aa5b2006-01-08 01:00:50 -0800282 if (check_pud_range(vma, pgd, addr, next, nodes,
Christoph Lameter38e35862006-01-08 01:01:01 -0800283 flags, private))
Hugh Dickins91612e02005-06-21 17:15:07 -0700284 return -EIO;
285 } while (pgd++, addr = next, addr != end);
286 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700287}
288
Christoph Lameterdc9aa5b2006-01-08 01:00:50 -0800289/* Check if a vma is migratable */
290static inline int vma_migratable(struct vm_area_struct *vma)
291{
292 if (vma->vm_flags & (
293 VM_LOCKED|VM_IO|VM_HUGETLB|VM_PFNMAP))
294 return 0;
295 return 1;
296}
297
298/*
299 * Check if all pages in a range are on a set of nodes.
300 * If pagelist != NULL then isolate pages from the LRU and
301 * put them on the pagelist.
302 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700303static struct vm_area_struct *
304check_range(struct mm_struct *mm, unsigned long start, unsigned long end,
Christoph Lameter38e35862006-01-08 01:01:01 -0800305 const nodemask_t *nodes, unsigned long flags, void *private)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700306{
307 int err;
308 struct vm_area_struct *first, *vma, *prev;
309
310 first = find_vma(mm, start);
311 if (!first)
312 return ERR_PTR(-EFAULT);
313 prev = NULL;
314 for (vma = first; vma && vma->vm_start < end; vma = vma->vm_next) {
Christoph Lameterdc9aa5b2006-01-08 01:00:50 -0800315 if (!(flags & MPOL_MF_DISCONTIG_OK)) {
316 if (!vma->vm_next && vma->vm_end < end)
317 return ERR_PTR(-EFAULT);
318 if (prev && prev->vm_end < vma->vm_start)
319 return ERR_PTR(-EFAULT);
320 }
321 if (!is_vm_hugetlb_page(vma) &&
322 ((flags & MPOL_MF_STRICT) ||
323 ((flags & (MPOL_MF_MOVE | MPOL_MF_MOVE_ALL)) &&
324 vma_migratable(vma)))) {
Andi Kleen5b952b32005-09-13 01:25:08 -0700325 unsigned long endvma = vma->vm_end;
Christoph Lameterdc9aa5b2006-01-08 01:00:50 -0800326
Andi Kleen5b952b32005-09-13 01:25:08 -0700327 if (endvma > end)
328 endvma = end;
329 if (vma->vm_start > start)
330 start = vma->vm_start;
Christoph Lameterdc9aa5b2006-01-08 01:00:50 -0800331 err = check_pgd_range(vma, start, endvma, nodes,
Christoph Lameter38e35862006-01-08 01:01:01 -0800332 flags, private);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700333 if (err) {
334 first = ERR_PTR(err);
335 break;
336 }
337 }
338 prev = vma;
339 }
340 return first;
341}
342
343/* Apply policy to a single VMA */
344static int policy_vma(struct vm_area_struct *vma, struct mempolicy *new)
345{
346 int err = 0;
347 struct mempolicy *old = vma->vm_policy;
348
349 PDprintk("vma %lx-%lx/%lx vm_ops %p vm_file %p set_policy %p\n",
350 vma->vm_start, vma->vm_end, vma->vm_pgoff,
351 vma->vm_ops, vma->vm_file,
352 vma->vm_ops ? vma->vm_ops->set_policy : NULL);
353
354 if (vma->vm_ops && vma->vm_ops->set_policy)
355 err = vma->vm_ops->set_policy(vma, new);
356 if (!err) {
357 mpol_get(new);
358 vma->vm_policy = new;
359 mpol_free(old);
360 }
361 return err;
362}
363
364/* Step 2: apply policy to a range and do splits. */
365static int mbind_range(struct vm_area_struct *vma, unsigned long start,
366 unsigned long end, struct mempolicy *new)
367{
368 struct vm_area_struct *next;
369 int err;
370
371 err = 0;
372 for (; vma && vma->vm_start < end; vma = next) {
373 next = vma->vm_next;
374 if (vma->vm_start < start)
375 err = split_vma(vma->vm_mm, vma, start, 1);
376 if (!err && vma->vm_end > end)
377 err = split_vma(vma->vm_mm, vma, end, 0);
378 if (!err)
379 err = policy_vma(vma, new);
380 if (err)
381 break;
382 }
383 return err;
384}
385
Christoph Lameter8bccd852005-10-29 18:16:59 -0700386static int contextualize_policy(int mode, nodemask_t *nodes)
387{
388 if (!nodes)
389 return 0;
390
Paul Jacksoncf2a4732006-01-08 01:01:54 -0800391 cpuset_update_task_memory_state();
Paul Jackson59665142006-01-08 01:01:47 -0800392 if (!cpuset_nodes_subset_current_mems_allowed(*nodes))
393 return -EINVAL;
Christoph Lameter8bccd852005-10-29 18:16:59 -0700394 return mpol_check_policy(mode, nodes);
395}
396
Linus Torvalds1da177e2005-04-16 15:20:36 -0700397/* Set the process memory policy */
Christoph Lameter8bccd852005-10-29 18:16:59 -0700398long do_set_mempolicy(int mode, nodemask_t *nodes)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700399{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700400 struct mempolicy *new;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700401
Christoph Lameter8bccd852005-10-29 18:16:59 -0700402 if (contextualize_policy(mode, nodes))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700403 return -EINVAL;
Christoph Lameter8bccd852005-10-29 18:16:59 -0700404 new = mpol_new(mode, nodes);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700405 if (IS_ERR(new))
406 return PTR_ERR(new);
407 mpol_free(current->mempolicy);
408 current->mempolicy = new;
409 if (new && new->policy == MPOL_INTERLEAVE)
Andi Kleendfcd3c02005-10-29 18:15:48 -0700410 current->il_next = first_node(new->v.nodes);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700411 return 0;
412}
413
414/* Fill a zone bitmap for a policy */
Andi Kleendfcd3c02005-10-29 18:15:48 -0700415static void get_zonemask(struct mempolicy *p, nodemask_t *nodes)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700416{
417 int i;
418
Andi Kleendfcd3c02005-10-29 18:15:48 -0700419 nodes_clear(*nodes);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700420 switch (p->policy) {
421 case MPOL_BIND:
422 for (i = 0; p->v.zonelist->zones[i]; i++)
Christoph Lameter8bccd852005-10-29 18:16:59 -0700423 node_set(p->v.zonelist->zones[i]->zone_pgdat->node_id,
424 *nodes);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700425 break;
426 case MPOL_DEFAULT:
427 break;
428 case MPOL_INTERLEAVE:
Andi Kleendfcd3c02005-10-29 18:15:48 -0700429 *nodes = p->v.nodes;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700430 break;
431 case MPOL_PREFERRED:
432 /* or use current node instead of online map? */
433 if (p->v.preferred_node < 0)
Andi Kleendfcd3c02005-10-29 18:15:48 -0700434 *nodes = node_online_map;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700435 else
Andi Kleendfcd3c02005-10-29 18:15:48 -0700436 node_set(p->v.preferred_node, *nodes);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700437 break;
438 default:
439 BUG();
440 }
441}
442
443static int lookup_node(struct mm_struct *mm, unsigned long addr)
444{
445 struct page *p;
446 int err;
447
448 err = get_user_pages(current, mm, addr & PAGE_MASK, 1, 0, 0, &p, NULL);
449 if (err >= 0) {
450 err = page_to_nid(p);
451 put_page(p);
452 }
453 return err;
454}
455
Linus Torvalds1da177e2005-04-16 15:20:36 -0700456/* Retrieve NUMA policy */
Christoph Lameter8bccd852005-10-29 18:16:59 -0700457long do_get_mempolicy(int *policy, nodemask_t *nmask,
458 unsigned long addr, unsigned long flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700459{
Christoph Lameter8bccd852005-10-29 18:16:59 -0700460 int err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700461 struct mm_struct *mm = current->mm;
462 struct vm_area_struct *vma = NULL;
463 struct mempolicy *pol = current->mempolicy;
464
Paul Jacksoncf2a4732006-01-08 01:01:54 -0800465 cpuset_update_task_memory_state();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700466 if (flags & ~(unsigned long)(MPOL_F_NODE|MPOL_F_ADDR))
467 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700468 if (flags & MPOL_F_ADDR) {
469 down_read(&mm->mmap_sem);
470 vma = find_vma_intersection(mm, addr, addr+1);
471 if (!vma) {
472 up_read(&mm->mmap_sem);
473 return -EFAULT;
474 }
475 if (vma->vm_ops && vma->vm_ops->get_policy)
476 pol = vma->vm_ops->get_policy(vma, addr);
477 else
478 pol = vma->vm_policy;
479 } else if (addr)
480 return -EINVAL;
481
482 if (!pol)
483 pol = &default_policy;
484
485 if (flags & MPOL_F_NODE) {
486 if (flags & MPOL_F_ADDR) {
487 err = lookup_node(mm, addr);
488 if (err < 0)
489 goto out;
Christoph Lameter8bccd852005-10-29 18:16:59 -0700490 *policy = err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700491 } else if (pol == current->mempolicy &&
492 pol->policy == MPOL_INTERLEAVE) {
Christoph Lameter8bccd852005-10-29 18:16:59 -0700493 *policy = current->il_next;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700494 } else {
495 err = -EINVAL;
496 goto out;
497 }
498 } else
Christoph Lameter8bccd852005-10-29 18:16:59 -0700499 *policy = pol->policy;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700500
501 if (vma) {
502 up_read(&current->mm->mmap_sem);
503 vma = NULL;
504 }
505
Linus Torvalds1da177e2005-04-16 15:20:36 -0700506 err = 0;
Christoph Lameter8bccd852005-10-29 18:16:59 -0700507 if (nmask)
508 get_zonemask(pol, nmask);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700509
510 out:
511 if (vma)
512 up_read(&current->mm->mmap_sem);
513 return err;
514}
515
Christoph Lameter8bccd852005-10-29 18:16:59 -0700516/*
Christoph Lameter6ce3c4c2006-01-08 01:01:04 -0800517 * page migration
518 */
519
520/* Check if we are the only process mapping the page in question */
521static inline int single_mm_mapping(struct mm_struct *mm,
522 struct address_space *mapping)
523{
524 struct vm_area_struct *vma;
525 struct prio_tree_iter iter;
526 int rc = 1;
527
528 spin_lock(&mapping->i_mmap_lock);
529 vma_prio_tree_foreach(vma, &iter, &mapping->i_mmap, 0, ULONG_MAX)
530 if (mm != vma->vm_mm) {
531 rc = 0;
532 goto out;
533 }
534 list_for_each_entry(vma, &mapping->i_mmap_nonlinear, shared.vm_set.list)
535 if (mm != vma->vm_mm) {
536 rc = 0;
537 goto out;
538 }
539out:
540 spin_unlock(&mapping->i_mmap_lock);
541 return rc;
542}
543
544/*
545 * Add a page to be migrated to the pagelist
546 */
547static void migrate_page_add(struct vm_area_struct *vma,
548 struct page *page, struct list_head *pagelist, unsigned long flags)
549{
550 /*
551 * Avoid migrating a page that is shared by others and not writable.
552 */
553 if ((flags & MPOL_MF_MOVE_ALL) || !page->mapping || PageAnon(page) ||
554 mapping_writably_mapped(page->mapping) ||
555 single_mm_mapping(vma->vm_mm, page->mapping)) {
556 int rc = isolate_lru_page(page);
557
558 if (rc == 1)
559 list_add(&page->lru, pagelist);
560 /*
561 * If the isolate attempt was not successful then we just
562 * encountered an unswappable page. Something must be wrong.
563 */
564 WARN_ON(rc == 0);
565 }
566}
567
568static int swap_pages(struct list_head *pagelist)
569{
570 LIST_HEAD(moved);
571 LIST_HEAD(failed);
572 int n;
573
574 n = migrate_pages(pagelist, NULL, &moved, &failed);
575 putback_lru_pages(&failed);
576 putback_lru_pages(&moved);
577
578 return n;
579}
580
581/*
Christoph Lameter39743882006-01-08 01:00:51 -0800582 * For now migrate_pages simply swaps out the pages from nodes that are in
583 * the source set but not in the target set. In the future, we would
584 * want a function that moves pages between the two nodesets in such
585 * a way as to preserve the physical layout as much as possible.
586 *
587 * Returns the number of page that could not be moved.
588 */
589int do_migrate_pages(struct mm_struct *mm,
590 const nodemask_t *from_nodes, const nodemask_t *to_nodes, int flags)
591{
592 LIST_HEAD(pagelist);
593 int count = 0;
594 nodemask_t nodes;
595
596 nodes_andnot(nodes, *from_nodes, *to_nodes);
Christoph Lameter39743882006-01-08 01:00:51 -0800597
598 down_read(&mm->mmap_sem);
599 check_range(mm, mm->mmap->vm_start, TASK_SIZE, &nodes,
600 flags | MPOL_MF_DISCONTIG_OK, &pagelist);
Christoph Lameterd4984712006-01-08 01:00:55 -0800601
Christoph Lameter39743882006-01-08 01:00:51 -0800602 if (!list_empty(&pagelist)) {
Christoph Lameterd4984712006-01-08 01:00:55 -0800603 count = swap_pages(&pagelist);
604 putback_lru_pages(&pagelist);
Christoph Lameter39743882006-01-08 01:00:51 -0800605 }
Christoph Lameterd4984712006-01-08 01:00:55 -0800606
Christoph Lameter39743882006-01-08 01:00:51 -0800607 up_read(&mm->mmap_sem);
608 return count;
609}
610
Christoph Lameter6ce3c4c2006-01-08 01:01:04 -0800611long do_mbind(unsigned long start, unsigned long len,
612 unsigned long mode, nodemask_t *nmask, unsigned long flags)
613{
614 struct vm_area_struct *vma;
615 struct mm_struct *mm = current->mm;
616 struct mempolicy *new;
617 unsigned long end;
618 int err;
619 LIST_HEAD(pagelist);
620
621 if ((flags & ~(unsigned long)(MPOL_MF_STRICT |
622 MPOL_MF_MOVE | MPOL_MF_MOVE_ALL))
623 || mode > MPOL_MAX)
624 return -EINVAL;
625 if ((flags & MPOL_MF_MOVE_ALL) && !capable(CAP_SYS_RESOURCE))
626 return -EPERM;
627
628 if (start & ~PAGE_MASK)
629 return -EINVAL;
630
631 if (mode == MPOL_DEFAULT)
632 flags &= ~MPOL_MF_STRICT;
633
634 len = (len + PAGE_SIZE - 1) & PAGE_MASK;
635 end = start + len;
636
637 if (end < start)
638 return -EINVAL;
639 if (end == start)
640 return 0;
641
642 if (mpol_check_policy(mode, nmask))
643 return -EINVAL;
644
645 new = mpol_new(mode, nmask);
646 if (IS_ERR(new))
647 return PTR_ERR(new);
648
649 /*
650 * If we are using the default policy then operation
651 * on discontinuous address spaces is okay after all
652 */
653 if (!new)
654 flags |= MPOL_MF_DISCONTIG_OK;
655
656 PDprintk("mbind %lx-%lx mode:%ld nodes:%lx\n",start,start+len,
657 mode,nodes_addr(nodes)[0]);
658
659 down_write(&mm->mmap_sem);
660 vma = check_range(mm, start, end, nmask,
661 flags | MPOL_MF_INVERT, &pagelist);
662
663 err = PTR_ERR(vma);
664 if (!IS_ERR(vma)) {
665 int nr_failed = 0;
666
667 err = mbind_range(vma, start, end, new);
668 if (!list_empty(&pagelist))
669 nr_failed = swap_pages(&pagelist);
670
671 if (!err && nr_failed && (flags & MPOL_MF_STRICT))
672 err = -EIO;
673 }
674 if (!list_empty(&pagelist))
675 putback_lru_pages(&pagelist);
676
677 up_write(&mm->mmap_sem);
678 mpol_free(new);
679 return err;
680}
681
Christoph Lameter39743882006-01-08 01:00:51 -0800682/*
Christoph Lameter8bccd852005-10-29 18:16:59 -0700683 * User space interface with variable sized bitmaps for nodelists.
684 */
685
686/* Copy a node mask from user space. */
Christoph Lameter39743882006-01-08 01:00:51 -0800687static int get_nodes(nodemask_t *nodes, const unsigned long __user *nmask,
Christoph Lameter8bccd852005-10-29 18:16:59 -0700688 unsigned long maxnode)
689{
690 unsigned long k;
691 unsigned long nlongs;
692 unsigned long endmask;
693
694 --maxnode;
695 nodes_clear(*nodes);
696 if (maxnode == 0 || !nmask)
697 return 0;
698
699 nlongs = BITS_TO_LONGS(maxnode);
700 if ((maxnode % BITS_PER_LONG) == 0)
701 endmask = ~0UL;
702 else
703 endmask = (1UL << (maxnode % BITS_PER_LONG)) - 1;
704
705 /* When the user specified more nodes than supported just check
706 if the non supported part is all zero. */
707 if (nlongs > BITS_TO_LONGS(MAX_NUMNODES)) {
708 if (nlongs > PAGE_SIZE/sizeof(long))
709 return -EINVAL;
710 for (k = BITS_TO_LONGS(MAX_NUMNODES); k < nlongs; k++) {
711 unsigned long t;
712 if (get_user(t, nmask + k))
713 return -EFAULT;
714 if (k == nlongs - 1) {
715 if (t & endmask)
716 return -EINVAL;
717 } else if (t)
718 return -EINVAL;
719 }
720 nlongs = BITS_TO_LONGS(MAX_NUMNODES);
721 endmask = ~0UL;
722 }
723
724 if (copy_from_user(nodes_addr(*nodes), nmask, nlongs*sizeof(unsigned long)))
725 return -EFAULT;
726 nodes_addr(*nodes)[nlongs-1] &= endmask;
727 return 0;
728}
729
730/* Copy a kernel node mask to user space */
731static int copy_nodes_to_user(unsigned long __user *mask, unsigned long maxnode,
732 nodemask_t *nodes)
733{
734 unsigned long copy = ALIGN(maxnode-1, 64) / 8;
735 const int nbytes = BITS_TO_LONGS(MAX_NUMNODES) * sizeof(long);
736
737 if (copy > nbytes) {
738 if (copy > PAGE_SIZE)
739 return -EINVAL;
740 if (clear_user((char __user *)mask + nbytes, copy - nbytes))
741 return -EFAULT;
742 copy = nbytes;
743 }
744 return copy_to_user(mask, nodes_addr(*nodes), copy) ? -EFAULT : 0;
745}
746
747asmlinkage long sys_mbind(unsigned long start, unsigned long len,
748 unsigned long mode,
749 unsigned long __user *nmask, unsigned long maxnode,
750 unsigned flags)
751{
752 nodemask_t nodes;
753 int err;
754
755 err = get_nodes(&nodes, nmask, maxnode);
756 if (err)
757 return err;
758 return do_mbind(start, len, mode, &nodes, flags);
759}
760
761/* Set the process memory policy */
762asmlinkage long sys_set_mempolicy(int mode, unsigned long __user *nmask,
763 unsigned long maxnode)
764{
765 int err;
766 nodemask_t nodes;
767
768 if (mode < 0 || mode > MPOL_MAX)
769 return -EINVAL;
770 err = get_nodes(&nodes, nmask, maxnode);
771 if (err)
772 return err;
773 return do_set_mempolicy(mode, &nodes);
774}
775
Christoph Lameter39743882006-01-08 01:00:51 -0800776asmlinkage long sys_migrate_pages(pid_t pid, unsigned long maxnode,
777 const unsigned long __user *old_nodes,
778 const unsigned long __user *new_nodes)
779{
780 struct mm_struct *mm;
781 struct task_struct *task;
782 nodemask_t old;
783 nodemask_t new;
784 nodemask_t task_nodes;
785 int err;
786
787 err = get_nodes(&old, old_nodes, maxnode);
788 if (err)
789 return err;
790
791 err = get_nodes(&new, new_nodes, maxnode);
792 if (err)
793 return err;
794
795 /* Find the mm_struct */
796 read_lock(&tasklist_lock);
797 task = pid ? find_task_by_pid(pid) : current;
798 if (!task) {
799 read_unlock(&tasklist_lock);
800 return -ESRCH;
801 }
802 mm = get_task_mm(task);
803 read_unlock(&tasklist_lock);
804
805 if (!mm)
806 return -EINVAL;
807
808 /*
809 * Check if this process has the right to modify the specified
810 * process. The right exists if the process has administrative
811 * capabilities, superuser priviledges or the same
812 * userid as the target process.
813 */
814 if ((current->euid != task->suid) && (current->euid != task->uid) &&
815 (current->uid != task->suid) && (current->uid != task->uid) &&
816 !capable(CAP_SYS_ADMIN)) {
817 err = -EPERM;
818 goto out;
819 }
820
821 task_nodes = cpuset_mems_allowed(task);
822 /* Is the user allowed to access the target nodes? */
823 if (!nodes_subset(new, task_nodes) && !capable(CAP_SYS_ADMIN)) {
824 err = -EPERM;
825 goto out;
826 }
827
828 err = do_migrate_pages(mm, &old, &new, MPOL_MF_MOVE);
829out:
830 mmput(mm);
831 return err;
832}
833
834
Christoph Lameter8bccd852005-10-29 18:16:59 -0700835/* Retrieve NUMA policy */
836asmlinkage long sys_get_mempolicy(int __user *policy,
837 unsigned long __user *nmask,
838 unsigned long maxnode,
839 unsigned long addr, unsigned long flags)
840{
841 int err, pval;
842 nodemask_t nodes;
843
844 if (nmask != NULL && maxnode < MAX_NUMNODES)
845 return -EINVAL;
846
847 err = do_get_mempolicy(&pval, &nodes, addr, flags);
848
849 if (err)
850 return err;
851
852 if (policy && put_user(pval, policy))
853 return -EFAULT;
854
855 if (nmask)
856 err = copy_nodes_to_user(nmask, maxnode, &nodes);
857
858 return err;
859}
860
Linus Torvalds1da177e2005-04-16 15:20:36 -0700861#ifdef CONFIG_COMPAT
862
863asmlinkage long compat_sys_get_mempolicy(int __user *policy,
864 compat_ulong_t __user *nmask,
865 compat_ulong_t maxnode,
866 compat_ulong_t addr, compat_ulong_t flags)
867{
868 long err;
869 unsigned long __user *nm = NULL;
870 unsigned long nr_bits, alloc_size;
871 DECLARE_BITMAP(bm, MAX_NUMNODES);
872
873 nr_bits = min_t(unsigned long, maxnode-1, MAX_NUMNODES);
874 alloc_size = ALIGN(nr_bits, BITS_PER_LONG) / 8;
875
876 if (nmask)
877 nm = compat_alloc_user_space(alloc_size);
878
879 err = sys_get_mempolicy(policy, nm, nr_bits+1, addr, flags);
880
881 if (!err && nmask) {
882 err = copy_from_user(bm, nm, alloc_size);
883 /* ensure entire bitmap is zeroed */
884 err |= clear_user(nmask, ALIGN(maxnode-1, 8) / 8);
885 err |= compat_put_bitmap(nmask, bm, nr_bits);
886 }
887
888 return err;
889}
890
891asmlinkage long compat_sys_set_mempolicy(int mode, compat_ulong_t __user *nmask,
892 compat_ulong_t maxnode)
893{
894 long err = 0;
895 unsigned long __user *nm = NULL;
896 unsigned long nr_bits, alloc_size;
897 DECLARE_BITMAP(bm, MAX_NUMNODES);
898
899 nr_bits = min_t(unsigned long, maxnode-1, MAX_NUMNODES);
900 alloc_size = ALIGN(nr_bits, BITS_PER_LONG) / 8;
901
902 if (nmask) {
903 err = compat_get_bitmap(bm, nmask, nr_bits);
904 nm = compat_alloc_user_space(alloc_size);
905 err |= copy_to_user(nm, bm, alloc_size);
906 }
907
908 if (err)
909 return -EFAULT;
910
911 return sys_set_mempolicy(mode, nm, nr_bits+1);
912}
913
914asmlinkage long compat_sys_mbind(compat_ulong_t start, compat_ulong_t len,
915 compat_ulong_t mode, compat_ulong_t __user *nmask,
916 compat_ulong_t maxnode, compat_ulong_t flags)
917{
918 long err = 0;
919 unsigned long __user *nm = NULL;
920 unsigned long nr_bits, alloc_size;
Andi Kleendfcd3c02005-10-29 18:15:48 -0700921 nodemask_t bm;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700922
923 nr_bits = min_t(unsigned long, maxnode-1, MAX_NUMNODES);
924 alloc_size = ALIGN(nr_bits, BITS_PER_LONG) / 8;
925
926 if (nmask) {
Andi Kleendfcd3c02005-10-29 18:15:48 -0700927 err = compat_get_bitmap(nodes_addr(bm), nmask, nr_bits);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700928 nm = compat_alloc_user_space(alloc_size);
Andi Kleendfcd3c02005-10-29 18:15:48 -0700929 err |= copy_to_user(nm, nodes_addr(bm), alloc_size);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700930 }
931
932 if (err)
933 return -EFAULT;
934
935 return sys_mbind(start, len, mode, nm, nr_bits+1, flags);
936}
937
938#endif
939
940/* Return effective policy for a VMA */
Christoph Lameter48fce342006-01-08 01:01:03 -0800941static struct mempolicy * get_vma_policy(struct task_struct *task,
942 struct vm_area_struct *vma, unsigned long addr)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700943{
Christoph Lameter6e21c8f2005-09-03 15:54:45 -0700944 struct mempolicy *pol = task->mempolicy;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700945
946 if (vma) {
947 if (vma->vm_ops && vma->vm_ops->get_policy)
Christoph Lameter8bccd852005-10-29 18:16:59 -0700948 pol = vma->vm_ops->get_policy(vma, addr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700949 else if (vma->vm_policy &&
950 vma->vm_policy->policy != MPOL_DEFAULT)
951 pol = vma->vm_policy;
952 }
953 if (!pol)
954 pol = &default_policy;
955 return pol;
956}
957
958/* Return a zonelist representing a mempolicy */
Al Virodd0fc662005-10-07 07:46:04 +0100959static struct zonelist *zonelist_policy(gfp_t gfp, struct mempolicy *policy)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700960{
961 int nd;
962
963 switch (policy->policy) {
964 case MPOL_PREFERRED:
965 nd = policy->v.preferred_node;
966 if (nd < 0)
967 nd = numa_node_id();
968 break;
969 case MPOL_BIND:
970 /* Lower zones don't get a policy applied */
971 /* Careful: current->mems_allowed might have moved */
Al Viroaf4ca452005-10-21 02:55:38 -0400972 if (gfp_zone(gfp) >= policy_zone)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700973 if (cpuset_zonelist_valid_mems_allowed(policy->v.zonelist))
974 return policy->v.zonelist;
975 /*FALL THROUGH*/
976 case MPOL_INTERLEAVE: /* should not happen */
977 case MPOL_DEFAULT:
978 nd = numa_node_id();
979 break;
980 default:
981 nd = 0;
982 BUG();
983 }
Al Viroaf4ca452005-10-21 02:55:38 -0400984 return NODE_DATA(nd)->node_zonelists + gfp_zone(gfp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700985}
986
987/* Do dynamic interleaving for a process */
988static unsigned interleave_nodes(struct mempolicy *policy)
989{
990 unsigned nid, next;
991 struct task_struct *me = current;
992
993 nid = me->il_next;
Andi Kleendfcd3c02005-10-29 18:15:48 -0700994 next = next_node(nid, policy->v.nodes);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700995 if (next >= MAX_NUMNODES)
Andi Kleendfcd3c02005-10-29 18:15:48 -0700996 next = first_node(policy->v.nodes);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700997 me->il_next = next;
998 return nid;
999}
1000
1001/* Do static interleaving for a VMA with known offset. */
1002static unsigned offset_il_node(struct mempolicy *pol,
1003 struct vm_area_struct *vma, unsigned long off)
1004{
Andi Kleendfcd3c02005-10-29 18:15:48 -07001005 unsigned nnodes = nodes_weight(pol->v.nodes);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001006 unsigned target = (unsigned)off % nnodes;
1007 int c;
1008 int nid = -1;
1009
1010 c = 0;
1011 do {
Andi Kleendfcd3c02005-10-29 18:15:48 -07001012 nid = next_node(nid, pol->v.nodes);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001013 c++;
1014 } while (c <= target);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001015 return nid;
1016}
1017
Christoph Lameter5da7ca82006-01-06 00:10:46 -08001018/* Determine a node number for interleave */
1019static inline unsigned interleave_nid(struct mempolicy *pol,
1020 struct vm_area_struct *vma, unsigned long addr, int shift)
1021{
1022 if (vma) {
1023 unsigned long off;
1024
1025 off = vma->vm_pgoff;
1026 off += (addr - vma->vm_start) >> shift;
1027 return offset_il_node(pol, vma, off);
1028 } else
1029 return interleave_nodes(pol);
1030}
1031
1032/* Return a zonelist suitable for a huge page allocation. */
1033struct zonelist *huge_zonelist(struct vm_area_struct *vma, unsigned long addr)
1034{
1035 struct mempolicy *pol = get_vma_policy(current, vma, addr);
1036
1037 if (pol->policy == MPOL_INTERLEAVE) {
1038 unsigned nid;
1039
1040 nid = interleave_nid(pol, vma, addr, HPAGE_SHIFT);
1041 return NODE_DATA(nid)->node_zonelists + gfp_zone(GFP_HIGHUSER);
1042 }
1043 return zonelist_policy(GFP_HIGHUSER, pol);
1044}
1045
Linus Torvalds1da177e2005-04-16 15:20:36 -07001046/* Allocate a page in interleaved policy.
1047 Own path because it needs to do special accounting. */
Andi Kleen662f3a02005-10-29 18:15:49 -07001048static struct page *alloc_page_interleave(gfp_t gfp, unsigned order,
1049 unsigned nid)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001050{
1051 struct zonelist *zl;
1052 struct page *page;
1053
Al Viroaf4ca452005-10-21 02:55:38 -04001054 zl = NODE_DATA(nid)->node_zonelists + gfp_zone(gfp);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001055 page = __alloc_pages(gfp, order, zl);
1056 if (page && page_zone(page) == zl->zones[0]) {
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07001057 zone_pcp(zl->zones[0],get_cpu())->interleave_hit++;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001058 put_cpu();
1059 }
1060 return page;
1061}
1062
1063/**
1064 * alloc_page_vma - Allocate a page for a VMA.
1065 *
1066 * @gfp:
1067 * %GFP_USER user allocation.
1068 * %GFP_KERNEL kernel allocations,
1069 * %GFP_HIGHMEM highmem/user allocations,
1070 * %GFP_FS allocation should not call back into a file system.
1071 * %GFP_ATOMIC don't sleep.
1072 *
1073 * @vma: Pointer to VMA or NULL if not available.
1074 * @addr: Virtual Address of the allocation. Must be inside the VMA.
1075 *
1076 * This function allocates a page from the kernel page pool and applies
1077 * a NUMA policy associated with the VMA or the current process.
1078 * When VMA is not NULL caller must hold down_read on the mmap_sem of the
1079 * mm_struct of the VMA to prevent it from going away. Should be used for
1080 * all allocations for pages that will be mapped into
1081 * user space. Returns NULL when no page can be allocated.
1082 *
1083 * Should be called with the mm_sem of the vma hold.
1084 */
1085struct page *
Al Virodd0fc662005-10-07 07:46:04 +01001086alloc_page_vma(gfp_t gfp, struct vm_area_struct *vma, unsigned long addr)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001087{
Christoph Lameter6e21c8f2005-09-03 15:54:45 -07001088 struct mempolicy *pol = get_vma_policy(current, vma, addr);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001089
Paul Jacksoncf2a4732006-01-08 01:01:54 -08001090 cpuset_update_task_memory_state();
Linus Torvalds1da177e2005-04-16 15:20:36 -07001091
1092 if (unlikely(pol->policy == MPOL_INTERLEAVE)) {
1093 unsigned nid;
Christoph Lameter5da7ca82006-01-06 00:10:46 -08001094
1095 nid = interleave_nid(pol, vma, addr, PAGE_SHIFT);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001096 return alloc_page_interleave(gfp, 0, nid);
1097 }
1098 return __alloc_pages(gfp, 0, zonelist_policy(gfp, pol));
1099}
1100
1101/**
1102 * alloc_pages_current - Allocate pages.
1103 *
1104 * @gfp:
1105 * %GFP_USER user allocation,
1106 * %GFP_KERNEL kernel allocation,
1107 * %GFP_HIGHMEM highmem allocation,
1108 * %GFP_FS don't call back into a file system.
1109 * %GFP_ATOMIC don't sleep.
1110 * @order: Power of two of allocation size in pages. 0 is a single page.
1111 *
1112 * Allocate a page from the kernel page pool. When not in
1113 * interrupt context and apply the current process NUMA policy.
1114 * Returns NULL when no page can be allocated.
1115 *
Paul Jacksoncf2a4732006-01-08 01:01:54 -08001116 * Don't call cpuset_update_task_memory_state() unless
Linus Torvalds1da177e2005-04-16 15:20:36 -07001117 * 1) it's ok to take cpuset_sem (can WAIT), and
1118 * 2) allocating for current task (not interrupt).
1119 */
Al Virodd0fc662005-10-07 07:46:04 +01001120struct page *alloc_pages_current(gfp_t gfp, unsigned order)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001121{
1122 struct mempolicy *pol = current->mempolicy;
1123
1124 if ((gfp & __GFP_WAIT) && !in_interrupt())
Paul Jacksoncf2a4732006-01-08 01:01:54 -08001125 cpuset_update_task_memory_state();
Linus Torvalds1da177e2005-04-16 15:20:36 -07001126 if (!pol || in_interrupt())
1127 pol = &default_policy;
1128 if (pol->policy == MPOL_INTERLEAVE)
1129 return alloc_page_interleave(gfp, order, interleave_nodes(pol));
1130 return __alloc_pages(gfp, order, zonelist_policy(gfp, pol));
1131}
1132EXPORT_SYMBOL(alloc_pages_current);
1133
Paul Jackson42253992006-01-08 01:01:59 -08001134/*
1135 * If mpol_copy() sees current->cpuset == cpuset_being_rebound, then it
1136 * rebinds the mempolicy its copying by calling mpol_rebind_policy()
1137 * with the mems_allowed returned by cpuset_mems_allowed(). This
1138 * keeps mempolicies cpuset relative after its cpuset moves. See
1139 * further kernel/cpuset.c update_nodemask().
1140 */
1141void *cpuset_being_rebound;
1142
Linus Torvalds1da177e2005-04-16 15:20:36 -07001143/* Slow path of a mempolicy copy */
1144struct mempolicy *__mpol_copy(struct mempolicy *old)
1145{
1146 struct mempolicy *new = kmem_cache_alloc(policy_cache, GFP_KERNEL);
1147
1148 if (!new)
1149 return ERR_PTR(-ENOMEM);
Paul Jackson42253992006-01-08 01:01:59 -08001150 if (current_cpuset_is_being_rebound()) {
1151 nodemask_t mems = cpuset_mems_allowed(current);
1152 mpol_rebind_policy(old, &mems);
1153 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001154 *new = *old;
1155 atomic_set(&new->refcnt, 1);
1156 if (new->policy == MPOL_BIND) {
1157 int sz = ksize(old->v.zonelist);
1158 new->v.zonelist = kmalloc(sz, SLAB_KERNEL);
1159 if (!new->v.zonelist) {
1160 kmem_cache_free(policy_cache, new);
1161 return ERR_PTR(-ENOMEM);
1162 }
1163 memcpy(new->v.zonelist, old->v.zonelist, sz);
1164 }
1165 return new;
1166}
1167
1168/* Slow path of a mempolicy comparison */
1169int __mpol_equal(struct mempolicy *a, struct mempolicy *b)
1170{
1171 if (!a || !b)
1172 return 0;
1173 if (a->policy != b->policy)
1174 return 0;
1175 switch (a->policy) {
1176 case MPOL_DEFAULT:
1177 return 1;
1178 case MPOL_INTERLEAVE:
Andi Kleendfcd3c02005-10-29 18:15:48 -07001179 return nodes_equal(a->v.nodes, b->v.nodes);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001180 case MPOL_PREFERRED:
1181 return a->v.preferred_node == b->v.preferred_node;
1182 case MPOL_BIND: {
1183 int i;
1184 for (i = 0; a->v.zonelist->zones[i]; i++)
1185 if (a->v.zonelist->zones[i] != b->v.zonelist->zones[i])
1186 return 0;
1187 return b->v.zonelist->zones[i] == NULL;
1188 }
1189 default:
1190 BUG();
1191 return 0;
1192 }
1193}
1194
1195/* Slow path of a mpol destructor. */
1196void __mpol_free(struct mempolicy *p)
1197{
1198 if (!atomic_dec_and_test(&p->refcnt))
1199 return;
1200 if (p->policy == MPOL_BIND)
1201 kfree(p->v.zonelist);
1202 p->policy = MPOL_DEFAULT;
1203 kmem_cache_free(policy_cache, p);
1204}
1205
1206/*
Linus Torvalds1da177e2005-04-16 15:20:36 -07001207 * Shared memory backing store policy support.
1208 *
1209 * Remember policies even when nobody has shared memory mapped.
1210 * The policies are kept in Red-Black tree linked from the inode.
1211 * They are protected by the sp->lock spinlock, which should be held
1212 * for any accesses to the tree.
1213 */
1214
1215/* lookup first element intersecting start-end */
1216/* Caller holds sp->lock */
1217static struct sp_node *
1218sp_lookup(struct shared_policy *sp, unsigned long start, unsigned long end)
1219{
1220 struct rb_node *n = sp->root.rb_node;
1221
1222 while (n) {
1223 struct sp_node *p = rb_entry(n, struct sp_node, nd);
1224
1225 if (start >= p->end)
1226 n = n->rb_right;
1227 else if (end <= p->start)
1228 n = n->rb_left;
1229 else
1230 break;
1231 }
1232 if (!n)
1233 return NULL;
1234 for (;;) {
1235 struct sp_node *w = NULL;
1236 struct rb_node *prev = rb_prev(n);
1237 if (!prev)
1238 break;
1239 w = rb_entry(prev, struct sp_node, nd);
1240 if (w->end <= start)
1241 break;
1242 n = prev;
1243 }
1244 return rb_entry(n, struct sp_node, nd);
1245}
1246
1247/* Insert a new shared policy into the list. */
1248/* Caller holds sp->lock */
1249static void sp_insert(struct shared_policy *sp, struct sp_node *new)
1250{
1251 struct rb_node **p = &sp->root.rb_node;
1252 struct rb_node *parent = NULL;
1253 struct sp_node *nd;
1254
1255 while (*p) {
1256 parent = *p;
1257 nd = rb_entry(parent, struct sp_node, nd);
1258 if (new->start < nd->start)
1259 p = &(*p)->rb_left;
1260 else if (new->end > nd->end)
1261 p = &(*p)->rb_right;
1262 else
1263 BUG();
1264 }
1265 rb_link_node(&new->nd, parent, p);
1266 rb_insert_color(&new->nd, &sp->root);
1267 PDprintk("inserting %lx-%lx: %d\n", new->start, new->end,
1268 new->policy ? new->policy->policy : 0);
1269}
1270
1271/* Find shared policy intersecting idx */
1272struct mempolicy *
1273mpol_shared_policy_lookup(struct shared_policy *sp, unsigned long idx)
1274{
1275 struct mempolicy *pol = NULL;
1276 struct sp_node *sn;
1277
1278 if (!sp->root.rb_node)
1279 return NULL;
1280 spin_lock(&sp->lock);
1281 sn = sp_lookup(sp, idx, idx+1);
1282 if (sn) {
1283 mpol_get(sn->policy);
1284 pol = sn->policy;
1285 }
1286 spin_unlock(&sp->lock);
1287 return pol;
1288}
1289
1290static void sp_delete(struct shared_policy *sp, struct sp_node *n)
1291{
1292 PDprintk("deleting %lx-l%x\n", n->start, n->end);
1293 rb_erase(&n->nd, &sp->root);
1294 mpol_free(n->policy);
1295 kmem_cache_free(sn_cache, n);
1296}
1297
1298struct sp_node *
1299sp_alloc(unsigned long start, unsigned long end, struct mempolicy *pol)
1300{
1301 struct sp_node *n = kmem_cache_alloc(sn_cache, GFP_KERNEL);
1302
1303 if (!n)
1304 return NULL;
1305 n->start = start;
1306 n->end = end;
1307 mpol_get(pol);
1308 n->policy = pol;
1309 return n;
1310}
1311
1312/* Replace a policy range. */
1313static int shared_policy_replace(struct shared_policy *sp, unsigned long start,
1314 unsigned long end, struct sp_node *new)
1315{
1316 struct sp_node *n, *new2 = NULL;
1317
1318restart:
1319 spin_lock(&sp->lock);
1320 n = sp_lookup(sp, start, end);
1321 /* Take care of old policies in the same range. */
1322 while (n && n->start < end) {
1323 struct rb_node *next = rb_next(&n->nd);
1324 if (n->start >= start) {
1325 if (n->end <= end)
1326 sp_delete(sp, n);
1327 else
1328 n->start = end;
1329 } else {
1330 /* Old policy spanning whole new range. */
1331 if (n->end > end) {
1332 if (!new2) {
1333 spin_unlock(&sp->lock);
1334 new2 = sp_alloc(end, n->end, n->policy);
1335 if (!new2)
1336 return -ENOMEM;
1337 goto restart;
1338 }
1339 n->end = start;
1340 sp_insert(sp, new2);
1341 new2 = NULL;
1342 break;
1343 } else
1344 n->end = start;
1345 }
1346 if (!next)
1347 break;
1348 n = rb_entry(next, struct sp_node, nd);
1349 }
1350 if (new)
1351 sp_insert(sp, new);
1352 spin_unlock(&sp->lock);
1353 if (new2) {
1354 mpol_free(new2->policy);
1355 kmem_cache_free(sn_cache, new2);
1356 }
1357 return 0;
1358}
1359
1360int mpol_set_shared_policy(struct shared_policy *info,
1361 struct vm_area_struct *vma, struct mempolicy *npol)
1362{
1363 int err;
1364 struct sp_node *new = NULL;
1365 unsigned long sz = vma_pages(vma);
1366
1367 PDprintk("set_shared_policy %lx sz %lu %d %lx\n",
1368 vma->vm_pgoff,
1369 sz, npol? npol->policy : -1,
Andi Kleendfcd3c02005-10-29 18:15:48 -07001370 npol ? nodes_addr(npol->v.nodes)[0] : -1);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001371
1372 if (npol) {
1373 new = sp_alloc(vma->vm_pgoff, vma->vm_pgoff + sz, npol);
1374 if (!new)
1375 return -ENOMEM;
1376 }
1377 err = shared_policy_replace(info, vma->vm_pgoff, vma->vm_pgoff+sz, new);
1378 if (err && new)
1379 kmem_cache_free(sn_cache, new);
1380 return err;
1381}
1382
1383/* Free a backing policy store on inode delete. */
1384void mpol_free_shared_policy(struct shared_policy *p)
1385{
1386 struct sp_node *n;
1387 struct rb_node *next;
1388
1389 if (!p->root.rb_node)
1390 return;
1391 spin_lock(&p->lock);
1392 next = rb_first(&p->root);
1393 while (next) {
1394 n = rb_entry(next, struct sp_node, nd);
1395 next = rb_next(&n->nd);
Andi Kleen90c50292005-07-27 11:43:50 -07001396 rb_erase(&n->nd, &p->root);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001397 mpol_free(n->policy);
1398 kmem_cache_free(sn_cache, n);
1399 }
1400 spin_unlock(&p->lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001401}
1402
1403/* assumes fs == KERNEL_DS */
1404void __init numa_policy_init(void)
1405{
1406 policy_cache = kmem_cache_create("numa_policy",
1407 sizeof(struct mempolicy),
1408 0, SLAB_PANIC, NULL, NULL);
1409
1410 sn_cache = kmem_cache_create("shared_policy_node",
1411 sizeof(struct sp_node),
1412 0, SLAB_PANIC, NULL, NULL);
1413
1414 /* Set interleaving policy for system init. This way not all
1415 the data structures allocated at system boot end up in node zero. */
1416
Christoph Lameter8bccd852005-10-29 18:16:59 -07001417 if (do_set_mempolicy(MPOL_INTERLEAVE, &node_online_map))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001418 printk("numa_policy_init: interleaving failed\n");
1419}
1420
Christoph Lameter8bccd852005-10-29 18:16:59 -07001421/* Reset policy of current process to default */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001422void numa_default_policy(void)
1423{
Christoph Lameter8bccd852005-10-29 18:16:59 -07001424 do_set_mempolicy(MPOL_DEFAULT, NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001425}
Paul Jackson68860ec2005-10-30 15:02:36 -08001426
1427/* Migrate a policy to a different set of nodes */
Paul Jackson74cb2152006-01-08 01:01:56 -08001428void mpol_rebind_policy(struct mempolicy *pol, const nodemask_t *newmask)
Paul Jackson68860ec2005-10-30 15:02:36 -08001429{
Paul Jackson74cb2152006-01-08 01:01:56 -08001430 nodemask_t *mpolmask;
Paul Jackson68860ec2005-10-30 15:02:36 -08001431 nodemask_t tmp;
1432
1433 if (!pol)
1434 return;
Paul Jackson74cb2152006-01-08 01:01:56 -08001435 mpolmask = &pol->cpuset_mems_allowed;
1436 if (nodes_equal(*mpolmask, *newmask))
1437 return;
Paul Jackson68860ec2005-10-30 15:02:36 -08001438
1439 switch (pol->policy) {
1440 case MPOL_DEFAULT:
1441 break;
1442 case MPOL_INTERLEAVE:
Paul Jackson74cb2152006-01-08 01:01:56 -08001443 nodes_remap(tmp, pol->v.nodes, *mpolmask, *newmask);
Paul Jackson68860ec2005-10-30 15:02:36 -08001444 pol->v.nodes = tmp;
Paul Jackson74cb2152006-01-08 01:01:56 -08001445 *mpolmask = *newmask;
1446 current->il_next = node_remap(current->il_next,
1447 *mpolmask, *newmask);
Paul Jackson68860ec2005-10-30 15:02:36 -08001448 break;
1449 case MPOL_PREFERRED:
1450 pol->v.preferred_node = node_remap(pol->v.preferred_node,
Paul Jackson74cb2152006-01-08 01:01:56 -08001451 *mpolmask, *newmask);
1452 *mpolmask = *newmask;
Paul Jackson68860ec2005-10-30 15:02:36 -08001453 break;
1454 case MPOL_BIND: {
1455 nodemask_t nodes;
1456 struct zone **z;
1457 struct zonelist *zonelist;
1458
1459 nodes_clear(nodes);
1460 for (z = pol->v.zonelist->zones; *z; z++)
1461 node_set((*z)->zone_pgdat->node_id, nodes);
Paul Jackson74cb2152006-01-08 01:01:56 -08001462 nodes_remap(tmp, nodes, *mpolmask, *newmask);
Paul Jackson68860ec2005-10-30 15:02:36 -08001463 nodes = tmp;
1464
1465 zonelist = bind_zonelist(&nodes);
1466
1467 /* If no mem, then zonelist is NULL and we keep old zonelist.
1468 * If that old zonelist has no remaining mems_allowed nodes,
1469 * then zonelist_policy() will "FALL THROUGH" to MPOL_DEFAULT.
1470 */
1471
1472 if (zonelist) {
1473 /* Good - got mem - substitute new zonelist */
1474 kfree(pol->v.zonelist);
1475 pol->v.zonelist = zonelist;
1476 }
Paul Jackson74cb2152006-01-08 01:01:56 -08001477 *mpolmask = *newmask;
Paul Jackson68860ec2005-10-30 15:02:36 -08001478 break;
1479 }
1480 default:
1481 BUG();
1482 break;
1483 }
1484}
1485
1486/*
Paul Jackson74cb2152006-01-08 01:01:56 -08001487 * Wrapper for mpol_rebind_policy() that just requires task
1488 * pointer, and updates task mempolicy.
Paul Jackson68860ec2005-10-30 15:02:36 -08001489 */
Paul Jackson74cb2152006-01-08 01:01:56 -08001490
1491void mpol_rebind_task(struct task_struct *tsk, const nodemask_t *new)
Paul Jackson68860ec2005-10-30 15:02:36 -08001492{
Paul Jackson74cb2152006-01-08 01:01:56 -08001493 mpol_rebind_policy(tsk->mempolicy, new);
Paul Jackson68860ec2005-10-30 15:02:36 -08001494}
Christoph Lameter1a75a6c2006-01-08 01:01:02 -08001495
1496/*
Paul Jackson42253992006-01-08 01:01:59 -08001497 * Rebind each vma in mm to new nodemask.
1498 *
1499 * Call holding a reference to mm. Takes mm->mmap_sem during call.
1500 */
1501
1502void mpol_rebind_mm(struct mm_struct *mm, nodemask_t *new)
1503{
1504 struct vm_area_struct *vma;
1505
1506 down_write(&mm->mmap_sem);
1507 for (vma = mm->mmap; vma; vma = vma->vm_next)
1508 mpol_rebind_policy(vma->vm_policy, new);
1509 up_write(&mm->mmap_sem);
1510}
1511
1512/*
Christoph Lameter1a75a6c2006-01-08 01:01:02 -08001513 * Display pages allocated per node and memory policy via /proc.
1514 */
1515
1516static const char *policy_types[] = { "default", "prefer", "bind",
1517 "interleave" };
1518
1519/*
1520 * Convert a mempolicy into a string.
1521 * Returns the number of characters in buffer (if positive)
1522 * or an error (negative)
1523 */
1524static inline int mpol_to_str(char *buffer, int maxlen, struct mempolicy *pol)
1525{
1526 char *p = buffer;
1527 int l;
1528 nodemask_t nodes;
1529 int mode = pol ? pol->policy : MPOL_DEFAULT;
1530
1531 switch (mode) {
1532 case MPOL_DEFAULT:
1533 nodes_clear(nodes);
1534 break;
1535
1536 case MPOL_PREFERRED:
1537 nodes_clear(nodes);
1538 node_set(pol->v.preferred_node, nodes);
1539 break;
1540
1541 case MPOL_BIND:
1542 get_zonemask(pol, &nodes);
1543 break;
1544
1545 case MPOL_INTERLEAVE:
1546 nodes = pol->v.nodes;
1547 break;
1548
1549 default:
1550 BUG();
1551 return -EFAULT;
1552 }
1553
1554 l = strlen(policy_types[mode]);
1555 if (buffer + maxlen < p + l + 1)
1556 return -ENOSPC;
1557
1558 strcpy(p, policy_types[mode]);
1559 p += l;
1560
1561 if (!nodes_empty(nodes)) {
1562 if (buffer + maxlen < p + 2)
1563 return -ENOSPC;
1564 *p++ = '=';
1565 p += nodelist_scnprintf(p, buffer + maxlen - p, nodes);
1566 }
1567 return p - buffer;
1568}
1569
1570struct numa_maps {
1571 unsigned long pages;
1572 unsigned long anon;
1573 unsigned long mapped;
1574 unsigned long mapcount_max;
1575 unsigned long node[MAX_NUMNODES];
1576};
1577
1578static void gather_stats(struct page *page, void *private)
1579{
1580 struct numa_maps *md = private;
1581 int count = page_mapcount(page);
1582
1583 if (count)
1584 md->mapped++;
1585
1586 if (count > md->mapcount_max)
1587 md->mapcount_max = count;
1588
1589 md->pages++;
1590
1591 if (PageAnon(page))
1592 md->anon++;
1593
1594 md->node[page_to_nid(page)]++;
1595 cond_resched();
1596}
1597
1598int show_numa_map(struct seq_file *m, void *v)
1599{
1600 struct task_struct *task = m->private;
1601 struct vm_area_struct *vma = v;
1602 struct numa_maps *md;
1603 int n;
1604 char buffer[50];
1605
1606 if (!vma->vm_mm)
1607 return 0;
1608
1609 md = kzalloc(sizeof(struct numa_maps), GFP_KERNEL);
1610 if (!md)
1611 return 0;
1612
1613 check_pgd_range(vma, vma->vm_start, vma->vm_end,
1614 &node_online_map, MPOL_MF_STATS, md);
1615
1616 if (md->pages) {
1617 mpol_to_str(buffer, sizeof(buffer),
1618 get_vma_policy(task, vma, vma->vm_start));
1619
1620 seq_printf(m, "%08lx %s pages=%lu mapped=%lu maxref=%lu",
1621 vma->vm_start, buffer, md->pages,
1622 md->mapped, md->mapcount_max);
1623
1624 if (md->anon)
1625 seq_printf(m," anon=%lu",md->anon);
1626
1627 for_each_online_node(n)
1628 if (md->node[n])
1629 seq_printf(m, " N%d=%lu", n, md->node[n]);
1630
1631 seq_putc(m, '\n');
1632 }
1633 kfree(md);
1634
1635 if (m->count < m->size)
1636 m->version = (vma != get_gate_vma(task)) ? vma->vm_start : 0;
1637 return 0;
1638}
1639