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1/*
2 * Basic Node interface support
3 */
4
5#include <linux/module.h>
6#include <linux/init.h>
7#include <linux/mm.h>
8#include <linux/memory.h>
9#include <linux/vmstat.h>
10#include <linux/node.h>
11#include <linux/hugetlb.h>
12#include <linux/compaction.h>
13#include <linux/cpumask.h>
14#include <linux/topology.h>
15#include <linux/nodemask.h>
16#include <linux/cpu.h>
17#include <linux/device.h>
18#include <linux/swap.h>
19#include <linux/slab.h>
20
21static struct bus_type node_subsys = {
22 .name = "node",
23 .dev_name = "node",
24};
25
26
27static ssize_t node_read_cpumap(struct device *dev, int type, char *buf)
28{
29 struct node *node_dev = to_node(dev);
30 const struct cpumask *mask = cpumask_of_node(node_dev->dev.id);
31 int len;
32
33 /* 2008/04/07: buf currently PAGE_SIZE, need 9 chars per 32 bits. */
34 BUILD_BUG_ON((NR_CPUS/32 * 9) > (PAGE_SIZE-1));
35
36 len = type?
37 cpulist_scnprintf(buf, PAGE_SIZE-2, mask) :
38 cpumask_scnprintf(buf, PAGE_SIZE-2, mask);
39 buf[len++] = '\n';
40 buf[len] = '\0';
41 return len;
42}
43
44static inline ssize_t node_read_cpumask(struct device *dev,
45 struct device_attribute *attr, char *buf)
46{
47 return node_read_cpumap(dev, 0, buf);
48}
49static inline ssize_t node_read_cpulist(struct device *dev,
50 struct device_attribute *attr, char *buf)
51{
52 return node_read_cpumap(dev, 1, buf);
53}
54
55static DEVICE_ATTR(cpumap, S_IRUGO, node_read_cpumask, NULL);
56static DEVICE_ATTR(cpulist, S_IRUGO, node_read_cpulist, NULL);
57
58#define K(x) ((x) << (PAGE_SHIFT - 10))
59static ssize_t node_read_meminfo(struct device *dev,
60 struct device_attribute *attr, char *buf)
61{
62 int n;
63 int nid = dev->id;
64 struct sysinfo i;
65
66 si_meminfo_node(&i, nid);
67 n = sprintf(buf,
68 "Node %d MemTotal: %8lu kB\n"
69 "Node %d MemFree: %8lu kB\n"
70 "Node %d MemUsed: %8lu kB\n"
71 "Node %d Active: %8lu kB\n"
72 "Node %d Inactive: %8lu kB\n"
73 "Node %d Active(anon): %8lu kB\n"
74 "Node %d Inactive(anon): %8lu kB\n"
75 "Node %d Active(file): %8lu kB\n"
76 "Node %d Inactive(file): %8lu kB\n"
77 "Node %d Unevictable: %8lu kB\n"
78 "Node %d Mlocked: %8lu kB\n",
79 nid, K(i.totalram),
80 nid, K(i.freeram),
81 nid, K(i.totalram - i.freeram),
82 nid, K(node_page_state(nid, NR_ACTIVE_ANON) +
83 node_page_state(nid, NR_ACTIVE_FILE)),
84 nid, K(node_page_state(nid, NR_INACTIVE_ANON) +
85 node_page_state(nid, NR_INACTIVE_FILE)),
86 nid, K(node_page_state(nid, NR_ACTIVE_ANON)),
87 nid, K(node_page_state(nid, NR_INACTIVE_ANON)),
88 nid, K(node_page_state(nid, NR_ACTIVE_FILE)),
89 nid, K(node_page_state(nid, NR_INACTIVE_FILE)),
90 nid, K(node_page_state(nid, NR_UNEVICTABLE)),
91 nid, K(node_page_state(nid, NR_MLOCK)));
92
93#ifdef CONFIG_HIGHMEM
94 n += sprintf(buf + n,
95 "Node %d HighTotal: %8lu kB\n"
96 "Node %d HighFree: %8lu kB\n"
97 "Node %d LowTotal: %8lu kB\n"
98 "Node %d LowFree: %8lu kB\n",
99 nid, K(i.totalhigh),
100 nid, K(i.freehigh),
101 nid, K(i.totalram - i.totalhigh),
102 nid, K(i.freeram - i.freehigh));
103#endif
104 n += sprintf(buf + n,
105 "Node %d Dirty: %8lu kB\n"
106 "Node %d Writeback: %8lu kB\n"
107 "Node %d FilePages: %8lu kB\n"
108 "Node %d Mapped: %8lu kB\n"
109 "Node %d AnonPages: %8lu kB\n"
110 "Node %d Shmem: %8lu kB\n"
111 "Node %d KernelStack: %8lu kB\n"
112 "Node %d PageTables: %8lu kB\n"
113 "Node %d NFS_Unstable: %8lu kB\n"
114 "Node %d Bounce: %8lu kB\n"
115 "Node %d WritebackTmp: %8lu kB\n"
116 "Node %d Slab: %8lu kB\n"
117 "Node %d SReclaimable: %8lu kB\n"
118 "Node %d SUnreclaim: %8lu kB\n"
119#ifdef CONFIG_TRANSPARENT_HUGEPAGE
120 "Node %d AnonHugePages: %8lu kB\n"
121#endif
122 ,
123 nid, K(node_page_state(nid, NR_FILE_DIRTY)),
124 nid, K(node_page_state(nid, NR_WRITEBACK)),
125 nid, K(node_page_state(nid, NR_FILE_PAGES)),
126 nid, K(node_page_state(nid, NR_FILE_MAPPED)),
127#ifdef CONFIG_TRANSPARENT_HUGEPAGE
128 nid, K(node_page_state(nid, NR_ANON_PAGES)
129 + node_page_state(nid, NR_ANON_TRANSPARENT_HUGEPAGES) *
130 HPAGE_PMD_NR),
131#else
132 nid, K(node_page_state(nid, NR_ANON_PAGES)),
133#endif
134 nid, K(node_page_state(nid, NR_SHMEM)),
135 nid, node_page_state(nid, NR_KERNEL_STACK) *
136 THREAD_SIZE / 1024,
137 nid, K(node_page_state(nid, NR_PAGETABLE)),
138 nid, K(node_page_state(nid, NR_UNSTABLE_NFS)),
139 nid, K(node_page_state(nid, NR_BOUNCE)),
140 nid, K(node_page_state(nid, NR_WRITEBACK_TEMP)),
141 nid, K(node_page_state(nid, NR_SLAB_RECLAIMABLE) +
142 node_page_state(nid, NR_SLAB_UNRECLAIMABLE)),
143 nid, K(node_page_state(nid, NR_SLAB_RECLAIMABLE)),
144#ifdef CONFIG_TRANSPARENT_HUGEPAGE
145 nid, K(node_page_state(nid, NR_SLAB_UNRECLAIMABLE))
146 , nid,
147 K(node_page_state(nid, NR_ANON_TRANSPARENT_HUGEPAGES) *
148 HPAGE_PMD_NR));
149#else
150 nid, K(node_page_state(nid, NR_SLAB_UNRECLAIMABLE)));
151#endif
152 n += hugetlb_report_node_meminfo(nid, buf + n);
153 return n;
154}
155
156#undef K
157static DEVICE_ATTR(meminfo, S_IRUGO, node_read_meminfo, NULL);
158
159static ssize_t node_read_numastat(struct device *dev,
160 struct device_attribute *attr, char *buf)
161{
162 return sprintf(buf,
163 "numa_hit %lu\n"
164 "numa_miss %lu\n"
165 "numa_foreign %lu\n"
166 "interleave_hit %lu\n"
167 "local_node %lu\n"
168 "other_node %lu\n",
169 node_page_state(dev->id, NUMA_HIT),
170 node_page_state(dev->id, NUMA_MISS),
171 node_page_state(dev->id, NUMA_FOREIGN),
172 node_page_state(dev->id, NUMA_INTERLEAVE_HIT),
173 node_page_state(dev->id, NUMA_LOCAL),
174 node_page_state(dev->id, NUMA_OTHER));
175}
176static DEVICE_ATTR(numastat, S_IRUGO, node_read_numastat, NULL);
177
178static ssize_t node_read_vmstat(struct device *dev,
179 struct device_attribute *attr, char *buf)
180{
181 int nid = dev->id;
182 int i;
183 int n = 0;
184
185 for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)
186 n += sprintf(buf+n, "%s %lu\n", vmstat_text[i],
187 node_page_state(nid, i));
188
189 return n;
190}
191static DEVICE_ATTR(vmstat, S_IRUGO, node_read_vmstat, NULL);
192
193static ssize_t node_read_distance(struct device *dev,
194 struct device_attribute *attr, char * buf)
195{
196 int nid = dev->id;
197 int len = 0;
198 int i;
199
200 /*
201 * buf is currently PAGE_SIZE in length and each node needs 4 chars
202 * at the most (distance + space or newline).
203 */
204 BUILD_BUG_ON(MAX_NUMNODES * 4 > PAGE_SIZE);
205
206 for_each_online_node(i)
207 len += sprintf(buf + len, "%s%d", i ? " " : "", node_distance(nid, i));
208
209 len += sprintf(buf + len, "\n");
210 return len;
211}
212static DEVICE_ATTR(distance, S_IRUGO, node_read_distance, NULL);
213
214#ifdef CONFIG_HUGETLBFS
215/*
216 * hugetlbfs per node attributes registration interface:
217 * When/if hugetlb[fs] subsystem initializes [sometime after this module],
218 * it will register its per node attributes for all online nodes with
219 * memory. It will also call register_hugetlbfs_with_node(), below, to
220 * register its attribute registration functions with this node driver.
221 * Once these hooks have been initialized, the node driver will call into
222 * the hugetlb module to [un]register attributes for hot-plugged nodes.
223 */
224static node_registration_func_t __hugetlb_register_node;
225static node_registration_func_t __hugetlb_unregister_node;
226
227static inline bool hugetlb_register_node(struct node *node)
228{
229 if (__hugetlb_register_node &&
230 node_state(node->dev.id, N_HIGH_MEMORY)) {
231 __hugetlb_register_node(node);
232 return true;
233 }
234 return false;
235}
236
237static inline void hugetlb_unregister_node(struct node *node)
238{
239 if (__hugetlb_unregister_node)
240 __hugetlb_unregister_node(node);
241}
242
243void register_hugetlbfs_with_node(node_registration_func_t doregister,
244 node_registration_func_t unregister)
245{
246 __hugetlb_register_node = doregister;
247 __hugetlb_unregister_node = unregister;
248}
249#else
250static inline void hugetlb_register_node(struct node *node) {}
251
252static inline void hugetlb_unregister_node(struct node *node) {}
253#endif
254
255
256/*
257 * register_node - Setup a sysfs device for a node.
258 * @num - Node number to use when creating the device.
259 *
260 * Initialize and register the node device.
261 */
262int register_node(struct node *node, int num, struct node *parent)
263{
264 int error;
265
266 node->dev.id = num;
267 node->dev.bus = &node_subsys;
268 error = device_register(&node->dev);
269
270 if (!error){
271 device_create_file(&node->dev, &dev_attr_cpumap);
272 device_create_file(&node->dev, &dev_attr_cpulist);
273 device_create_file(&node->dev, &dev_attr_meminfo);
274 device_create_file(&node->dev, &dev_attr_numastat);
275 device_create_file(&node->dev, &dev_attr_distance);
276 device_create_file(&node->dev, &dev_attr_vmstat);
277
278 scan_unevictable_register_node(node);
279
280 hugetlb_register_node(node);
281
282 compaction_register_node(node);
283 }
284 return error;
285}
286
287/**
288 * unregister_node - unregister a node device
289 * @node: node going away
290 *
291 * Unregisters a node device @node. All the devices on the node must be
292 * unregistered before calling this function.
293 */
294void unregister_node(struct node *node)
295{
296 device_remove_file(&node->dev, &dev_attr_cpumap);
297 device_remove_file(&node->dev, &dev_attr_cpulist);
298 device_remove_file(&node->dev, &dev_attr_meminfo);
299 device_remove_file(&node->dev, &dev_attr_numastat);
300 device_remove_file(&node->dev, &dev_attr_distance);
301 device_remove_file(&node->dev, &dev_attr_vmstat);
302
303 scan_unevictable_unregister_node(node);
304 hugetlb_unregister_node(node); /* no-op, if memoryless node */
305
306 device_unregister(&node->dev);
307}
308
309struct node node_devices[MAX_NUMNODES];
310
311/*
312 * register cpu under node
313 */
314int register_cpu_under_node(unsigned int cpu, unsigned int nid)
315{
316 int ret;
317 struct device *obj;
318
319 if (!node_online(nid))
320 return 0;
321
322 obj = get_cpu_device(cpu);
323 if (!obj)
324 return 0;
325
326 ret = sysfs_create_link(&node_devices[nid].dev.kobj,
327 &obj->kobj,
328 kobject_name(&obj->kobj));
329 if (ret)
330 return ret;
331
332 return sysfs_create_link(&obj->kobj,
333 &node_devices[nid].dev.kobj,
334 kobject_name(&node_devices[nid].dev.kobj));
335}
336
337int unregister_cpu_under_node(unsigned int cpu, unsigned int nid)
338{
339 struct device *obj;
340
341 if (!node_online(nid))
342 return 0;
343
344 obj = get_cpu_device(cpu);
345 if (!obj)
346 return 0;
347
348 sysfs_remove_link(&node_devices[nid].dev.kobj,
349 kobject_name(&obj->kobj));
350 sysfs_remove_link(&obj->kobj,
351 kobject_name(&node_devices[nid].dev.kobj));
352
353 return 0;
354}
355
356#ifdef CONFIG_MEMORY_HOTPLUG_SPARSE
357#define page_initialized(page) (page->lru.next)
358
359static int get_nid_for_pfn(unsigned long pfn)
360{
361 struct page *page;
362
363 if (!pfn_valid_within(pfn))
364 return -1;
365 page = pfn_to_page(pfn);
366 if (!page_initialized(page))
367 return -1;
368 return pfn_to_nid(pfn);
369}
370
371/* register memory section under specified node if it spans that node */
372int register_mem_sect_under_node(struct memory_block *mem_blk, int nid)
373{
374 int ret;
375 unsigned long pfn, sect_start_pfn, sect_end_pfn;
376
377 if (!mem_blk)
378 return -EFAULT;
379 if (!node_online(nid))
380 return 0;
381
382 sect_start_pfn = section_nr_to_pfn(mem_blk->start_section_nr);
383 sect_end_pfn = section_nr_to_pfn(mem_blk->end_section_nr);
384 sect_end_pfn += PAGES_PER_SECTION - 1;
385 for (pfn = sect_start_pfn; pfn <= sect_end_pfn; pfn++) {
386 int page_nid;
387
388 page_nid = get_nid_for_pfn(pfn);
389 if (page_nid < 0)
390 continue;
391 if (page_nid != nid)
392 continue;
393 ret = sysfs_create_link_nowarn(&node_devices[nid].dev.kobj,
394 &mem_blk->dev.kobj,
395 kobject_name(&mem_blk->dev.kobj));
396 if (ret)
397 return ret;
398
399 return sysfs_create_link_nowarn(&mem_blk->dev.kobj,
400 &node_devices[nid].dev.kobj,
401 kobject_name(&node_devices[nid].dev.kobj));
402 }
403 /* mem section does not span the specified node */
404 return 0;
405}
406
407/* unregister memory section under all nodes that it spans */
408int unregister_mem_sect_under_nodes(struct memory_block *mem_blk,
409 unsigned long phys_index)
410{
411 NODEMASK_ALLOC(nodemask_t, unlinked_nodes, GFP_KERNEL);
412 unsigned long pfn, sect_start_pfn, sect_end_pfn;
413
414 if (!mem_blk) {
415 NODEMASK_FREE(unlinked_nodes);
416 return -EFAULT;
417 }
418 if (!unlinked_nodes)
419 return -ENOMEM;
420 nodes_clear(*unlinked_nodes);
421
422 sect_start_pfn = section_nr_to_pfn(phys_index);
423 sect_end_pfn = sect_start_pfn + PAGES_PER_SECTION - 1;
424 for (pfn = sect_start_pfn; pfn <= sect_end_pfn; pfn++) {
425 int nid;
426
427 nid = get_nid_for_pfn(pfn);
428 if (nid < 0)
429 continue;
430 if (!node_online(nid))
431 continue;
432 if (node_test_and_set(nid, *unlinked_nodes))
433 continue;
434 sysfs_remove_link(&node_devices[nid].dev.kobj,
435 kobject_name(&mem_blk->dev.kobj));
436 sysfs_remove_link(&mem_blk->dev.kobj,
437 kobject_name(&node_devices[nid].dev.kobj));
438 }
439 NODEMASK_FREE(unlinked_nodes);
440 return 0;
441}
442
443static int link_mem_sections(int nid)
444{
445 unsigned long start_pfn = NODE_DATA(nid)->node_start_pfn;
446 unsigned long end_pfn = start_pfn + NODE_DATA(nid)->node_spanned_pages;
447 unsigned long pfn;
448 struct memory_block *mem_blk = NULL;
449 int err = 0;
450
451 for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
452 unsigned long section_nr = pfn_to_section_nr(pfn);
453 struct mem_section *mem_sect;
454 int ret;
455
456 if (!present_section_nr(section_nr))
457 continue;
458 mem_sect = __nr_to_section(section_nr);
459
460 /* same memblock ? */
461 if (mem_blk)
462 if ((section_nr >= mem_blk->start_section_nr) &&
463 (section_nr <= mem_blk->end_section_nr))
464 continue;
465
466 mem_blk = find_memory_block_hinted(mem_sect, mem_blk);
467
468 ret = register_mem_sect_under_node(mem_blk, nid);
469 if (!err)
470 err = ret;
471
472 /* discard ref obtained in find_memory_block() */
473 }
474
475 if (mem_blk)
476 kobject_put(&mem_blk->dev.kobj);
477 return err;
478}
479
480#ifdef CONFIG_HUGETLBFS
481/*
482 * Handle per node hstate attribute [un]registration on transistions
483 * to/from memoryless state.
484 */
485static void node_hugetlb_work(struct work_struct *work)
486{
487 struct node *node = container_of(work, struct node, node_work);
488
489 /*
490 * We only get here when a node transitions to/from memoryless state.
491 * We can detect which transition occurred by examining whether the
492 * node has memory now. hugetlb_register_node() already check this
493 * so we try to register the attributes. If that fails, then the
494 * node has transitioned to memoryless, try to unregister the
495 * attributes.
496 */
497 if (!hugetlb_register_node(node))
498 hugetlb_unregister_node(node);
499}
500
501static void init_node_hugetlb_work(int nid)
502{
503 INIT_WORK(&node_devices[nid].node_work, node_hugetlb_work);
504}
505
506static int node_memory_callback(struct notifier_block *self,
507 unsigned long action, void *arg)
508{
509 struct memory_notify *mnb = arg;
510 int nid = mnb->status_change_nid;
511
512 switch (action) {
513 case MEM_ONLINE:
514 case MEM_OFFLINE:
515 /*
516 * offload per node hstate [un]registration to a work thread
517 * when transitioning to/from memoryless state.
518 */
519 if (nid != NUMA_NO_NODE)
520 schedule_work(&node_devices[nid].node_work);
521 break;
522
523 case MEM_GOING_ONLINE:
524 case MEM_GOING_OFFLINE:
525 case MEM_CANCEL_ONLINE:
526 case MEM_CANCEL_OFFLINE:
527 default:
528 break;
529 }
530
531 return NOTIFY_OK;
532}
533#endif /* CONFIG_HUGETLBFS */
534#else /* !CONFIG_MEMORY_HOTPLUG_SPARSE */
535
536static int link_mem_sections(int nid) { return 0; }
537#endif /* CONFIG_MEMORY_HOTPLUG_SPARSE */
538
539#if !defined(CONFIG_MEMORY_HOTPLUG_SPARSE) || \
540 !defined(CONFIG_HUGETLBFS)
541static inline int node_memory_callback(struct notifier_block *self,
542 unsigned long action, void *arg)
543{
544 return NOTIFY_OK;
545}
546
547static void init_node_hugetlb_work(int nid) { }
548
549#endif
550
551int register_one_node(int nid)
552{
553 int error = 0;
554 int cpu;
555
556 if (node_online(nid)) {
557 int p_node = parent_node(nid);
558 struct node *parent = NULL;
559
560 if (p_node != nid)
561 parent = &node_devices[p_node];
562
563 error = register_node(&node_devices[nid], nid, parent);
564
565 /* link cpu under this node */
566 for_each_present_cpu(cpu) {
567 if (cpu_to_node(cpu) == nid)
568 register_cpu_under_node(cpu, nid);
569 }
570
571 /* link memory sections under this node */
572 error = link_mem_sections(nid);
573
574 /* initialize work queue for memory hot plug */
575 init_node_hugetlb_work(nid);
576 }
577
578 return error;
579
580}
581
582void unregister_one_node(int nid)
583{
584 unregister_node(&node_devices[nid]);
585}
586
587/*
588 * node states attributes
589 */
590
591static ssize_t print_nodes_state(enum node_states state, char *buf)
592{
593 int n;
594
595 n = nodelist_scnprintf(buf, PAGE_SIZE-2, node_states[state]);
596 buf[n++] = '\n';
597 buf[n] = '\0';
598 return n;
599}
600
601struct node_attr {
602 struct device_attribute attr;
603 enum node_states state;
604};
605
606static ssize_t show_node_state(struct device *dev,
607 struct device_attribute *attr, char *buf)
608{
609 struct node_attr *na = container_of(attr, struct node_attr, attr);
610 return print_nodes_state(na->state, buf);
611}
612
613#define _NODE_ATTR(name, state) \
614 { __ATTR(name, 0444, show_node_state, NULL), state }
615
616static struct node_attr node_state_attr[] = {
617 _NODE_ATTR(possible, N_POSSIBLE),
618 _NODE_ATTR(online, N_ONLINE),
619 _NODE_ATTR(has_normal_memory, N_NORMAL_MEMORY),
620 _NODE_ATTR(has_cpu, N_CPU),
621#ifdef CONFIG_HIGHMEM
622 _NODE_ATTR(has_high_memory, N_HIGH_MEMORY),
623#endif
624};
625
626static struct attribute *node_state_attrs[] = {
627 &node_state_attr[0].attr.attr,
628 &node_state_attr[1].attr.attr,
629 &node_state_attr[2].attr.attr,
630 &node_state_attr[3].attr.attr,
631#ifdef CONFIG_HIGHMEM
632 &node_state_attr[4].attr.attr,
633#endif
634 NULL
635};
636
637static struct attribute_group memory_root_attr_group = {
638 .attrs = node_state_attrs,
639};
640
641static const struct attribute_group *cpu_root_attr_groups[] = {
642 &memory_root_attr_group,
643 NULL,
644};
645
646#define NODE_CALLBACK_PRI 2 /* lower than SLAB */
647static int __init register_node_type(void)
648{
649 int ret;
650
651 BUILD_BUG_ON(ARRAY_SIZE(node_state_attr) != NR_NODE_STATES);
652 BUILD_BUG_ON(ARRAY_SIZE(node_state_attrs)-1 != NR_NODE_STATES);
653
654 ret = subsys_system_register(&node_subsys, cpu_root_attr_groups);
655 if (!ret) {
656 hotplug_memory_notifier(node_memory_callback,
657 NODE_CALLBACK_PRI);
658 }
659
660 /*
661 * Note: we're not going to unregister the node class if we fail
662 * to register the node state class attribute files.
663 */
664 return ret;
665}
666postcore_initcall(register_node_type);