projects/linux·blob v5.8 · refs

1029 lines · 26.8 KiB

1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Basic Node interface support
4 */
5
6#include <linux/module.h>
7#include <linux/init.h>
8#include <linux/mm.h>
9#include <linux/memory.h>
10#include <linux/vmstat.h>
11#include <linux/notifier.h>
12#include <linux/node.h>
13#include <linux/hugetlb.h>
14#include <linux/compaction.h>
15#include <linux/cpumask.h>
16#include <linux/topology.h>
17#include <linux/nodemask.h>
18#include <linux/cpu.h>
19#include <linux/device.h>
20#include <linux/pm_runtime.h>
21#include <linux/swap.h>
22#include <linux/slab.h>
23
24static struct bus_type node_subsys = {
25 .name = "node",
26 .dev_name = "node",
27};
28
29
30static ssize_t node_read_cpumap(struct device *dev, bool list, char *buf)
31{
32 ssize_t n;
33 cpumask_var_t mask;
34 struct node *node_dev = to_node(dev);
35
36 /* 2008/04/07: buf currently PAGE_SIZE, need 9 chars per 32 bits. */
37 BUILD_BUG_ON((NR_CPUS/32 * 9) > (PAGE_SIZE-1));
38
39 if (!alloc_cpumask_var(&mask, GFP_KERNEL))
40 return 0;
41
42 cpumask_and(mask, cpumask_of_node(node_dev->dev.id), cpu_online_mask);
43 n = cpumap_print_to_pagebuf(list, buf, mask);
44 free_cpumask_var(mask);
45
46 return n;
47}
48
49static inline ssize_t node_read_cpumask(struct device *dev,
50 struct device_attribute *attr, char *buf)
51{
52 return node_read_cpumap(dev, false, buf);
53}
54static inline ssize_t node_read_cpulist(struct device *dev,
55 struct device_attribute *attr, char *buf)
56{
57 return node_read_cpumap(dev, true, buf);
58}
59
60static DEVICE_ATTR(cpumap, S_IRUGO, node_read_cpumask, NULL);
61static DEVICE_ATTR(cpulist, S_IRUGO, node_read_cpulist, NULL);
62
63/**
64 * struct node_access_nodes - Access class device to hold user visible
65 * relationships to other nodes.
66 * @dev: Device for this memory access class
67 * @list_node: List element in the node's access list
68 * @access: The access class rank
69 * @hmem_attrs: Heterogeneous memory performance attributes
70 */
71struct node_access_nodes {
72 struct device dev;
73 struct list_head list_node;
74 unsigned access;
75#ifdef CONFIG_HMEM_REPORTING
76 struct node_hmem_attrs hmem_attrs;
77#endif
78};
79#define to_access_nodes(dev) container_of(dev, struct node_access_nodes, dev)
80
81static struct attribute *node_init_access_node_attrs[] = {
82 NULL,
83};
84
85static struct attribute *node_targ_access_node_attrs[] = {
86 NULL,
87};
88
89static const struct attribute_group initiators = {
90 .name = "initiators",
91 .attrs = node_init_access_node_attrs,
92};
93
94static const struct attribute_group targets = {
95 .name = "targets",
96 .attrs = node_targ_access_node_attrs,
97};
98
99static const struct attribute_group *node_access_node_groups[] = {
100 &initiators,
101 &targets,
102 NULL,
103};
104
105static void node_remove_accesses(struct node *node)
106{
107 struct node_access_nodes *c, *cnext;
108
109 list_for_each_entry_safe(c, cnext, &node->access_list, list_node) {
110 list_del(&c->list_node);
111 device_unregister(&c->dev);
112 }
113}
114
115static void node_access_release(struct device *dev)
116{
117 kfree(to_access_nodes(dev));
118}
119
120static struct node_access_nodes *node_init_node_access(struct node *node,
121 unsigned access)
122{
123 struct node_access_nodes *access_node;
124 struct device *dev;
125
126 list_for_each_entry(access_node, &node->access_list, list_node)
127 if (access_node->access == access)
128 return access_node;
129
130 access_node = kzalloc(sizeof(*access_node), GFP_KERNEL);
131 if (!access_node)
132 return NULL;
133
134 access_node->access = access;
135 dev = &access_node->dev;
136 dev->parent = &node->dev;
137 dev->release = node_access_release;
138 dev->groups = node_access_node_groups;
139 if (dev_set_name(dev, "access%u", access))
140 goto free;
141
142 if (device_register(dev))
143 goto free_name;
144
145 pm_runtime_no_callbacks(dev);
146 list_add_tail(&access_node->list_node, &node->access_list);
147 return access_node;
148free_name:
149 kfree_const(dev->kobj.name);
150free:
151 kfree(access_node);
152 return NULL;
153}
154
155#ifdef CONFIG_HMEM_REPORTING
156#define ACCESS_ATTR(name) \
157static ssize_t name##_show(struct device *dev, \
158 struct device_attribute *attr, \
159 char *buf) \
160{ \
161 return sprintf(buf, "%u\n", to_access_nodes(dev)->hmem_attrs.name); \
162} \
163static DEVICE_ATTR_RO(name);
164
165ACCESS_ATTR(read_bandwidth)
166ACCESS_ATTR(read_latency)
167ACCESS_ATTR(write_bandwidth)
168ACCESS_ATTR(write_latency)
169
170static struct attribute *access_attrs[] = {
171 &dev_attr_read_bandwidth.attr,
172 &dev_attr_read_latency.attr,
173 &dev_attr_write_bandwidth.attr,
174 &dev_attr_write_latency.attr,
175 NULL,
176};
177
178/**
179 * node_set_perf_attrs - Set the performance values for given access class
180 * @nid: Node identifier to be set
181 * @hmem_attrs: Heterogeneous memory performance attributes
182 * @access: The access class the for the given attributes
183 */
184void node_set_perf_attrs(unsigned int nid, struct node_hmem_attrs *hmem_attrs,
185 unsigned access)
186{
187 struct node_access_nodes *c;
188 struct node *node;
189 int i;
190
191 if (WARN_ON_ONCE(!node_online(nid)))
192 return;
193
194 node = node_devices[nid];
195 c = node_init_node_access(node, access);
196 if (!c)
197 return;
198
199 c->hmem_attrs = *hmem_attrs;
200 for (i = 0; access_attrs[i] != NULL; i++) {
201 if (sysfs_add_file_to_group(&c->dev.kobj, access_attrs[i],
202 "initiators")) {
203 pr_info("failed to add performance attribute to node %d\n",
204 nid);
205 break;
206 }
207 }
208}
209
210/**
211 * struct node_cache_info - Internal tracking for memory node caches
212 * @dev: Device represeting the cache level
213 * @node: List element for tracking in the node
214 * @cache_attrs:Attributes for this cache level
215 */
216struct node_cache_info {
217 struct device dev;
218 struct list_head node;
219 struct node_cache_attrs cache_attrs;
220};
221#define to_cache_info(device) container_of(device, struct node_cache_info, dev)
222
223#define CACHE_ATTR(name, fmt) \
224static ssize_t name##_show(struct device *dev, \
225 struct device_attribute *attr, \
226 char *buf) \
227{ \
228 return sprintf(buf, fmt "\n", to_cache_info(dev)->cache_attrs.name);\
229} \
230DEVICE_ATTR_RO(name);
231
232CACHE_ATTR(size, "%llu")
233CACHE_ATTR(line_size, "%u")
234CACHE_ATTR(indexing, "%u")
235CACHE_ATTR(write_policy, "%u")
236
237static struct attribute *cache_attrs[] = {
238 &dev_attr_indexing.attr,
239 &dev_attr_size.attr,
240 &dev_attr_line_size.attr,
241 &dev_attr_write_policy.attr,
242 NULL,
243};
244ATTRIBUTE_GROUPS(cache);
245
246static void node_cache_release(struct device *dev)
247{
248 kfree(dev);
249}
250
251static void node_cacheinfo_release(struct device *dev)
252{
253 struct node_cache_info *info = to_cache_info(dev);
254 kfree(info);
255}
256
257static void node_init_cache_dev(struct node *node)
258{
259 struct device *dev;
260
261 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
262 if (!dev)
263 return;
264
265 dev->parent = &node->dev;
266 dev->release = node_cache_release;
267 if (dev_set_name(dev, "memory_side_cache"))
268 goto free_dev;
269
270 if (device_register(dev))
271 goto free_name;
272
273 pm_runtime_no_callbacks(dev);
274 node->cache_dev = dev;
275 return;
276free_name:
277 kfree_const(dev->kobj.name);
278free_dev:
279 kfree(dev);
280}
281
282/**
283 * node_add_cache() - add cache attribute to a memory node
284 * @nid: Node identifier that has new cache attributes
285 * @cache_attrs: Attributes for the cache being added
286 */
287void node_add_cache(unsigned int nid, struct node_cache_attrs *cache_attrs)
288{
289 struct node_cache_info *info;
290 struct device *dev;
291 struct node *node;
292
293 if (!node_online(nid) || !node_devices[nid])
294 return;
295
296 node = node_devices[nid];
297 list_for_each_entry(info, &node->cache_attrs, node) {
298 if (info->cache_attrs.level == cache_attrs->level) {
299 dev_warn(&node->dev,
300 "attempt to add duplicate cache level:%d\n",
301 cache_attrs->level);
302 return;
303 }
304 }
305
306 if (!node->cache_dev)
307 node_init_cache_dev(node);
308 if (!node->cache_dev)
309 return;
310
311 info = kzalloc(sizeof(*info), GFP_KERNEL);
312 if (!info)
313 return;
314
315 dev = &info->dev;
316 dev->parent = node->cache_dev;
317 dev->release = node_cacheinfo_release;
318 dev->groups = cache_groups;
319 if (dev_set_name(dev, "index%d", cache_attrs->level))
320 goto free_cache;
321
322 info->cache_attrs = *cache_attrs;
323 if (device_register(dev)) {
324 dev_warn(&node->dev, "failed to add cache level:%d\n",
325 cache_attrs->level);
326 goto free_name;
327 }
328 pm_runtime_no_callbacks(dev);
329 list_add_tail(&info->node, &node->cache_attrs);
330 return;
331free_name:
332 kfree_const(dev->kobj.name);
333free_cache:
334 kfree(info);
335}
336
337static void node_remove_caches(struct node *node)
338{
339 struct node_cache_info *info, *next;
340
341 if (!node->cache_dev)
342 return;
343
344 list_for_each_entry_safe(info, next, &node->cache_attrs, node) {
345 list_del(&info->node);
346 device_unregister(&info->dev);
347 }
348 device_unregister(node->cache_dev);
349}
350
351static void node_init_caches(unsigned int nid)
352{
353 INIT_LIST_HEAD(&node_devices[nid]->cache_attrs);
354}
355#else
356static void node_init_caches(unsigned int nid) { }
357static void node_remove_caches(struct node *node) { }
358#endif
359
360#define K(x) ((x) << (PAGE_SHIFT - 10))
361static ssize_t node_read_meminfo(struct device *dev,
362 struct device_attribute *attr, char *buf)
363{
364 int n;
365 int nid = dev->id;
366 struct pglist_data *pgdat = NODE_DATA(nid);
367 struct sysinfo i;
368 unsigned long sreclaimable, sunreclaimable;
369
370 si_meminfo_node(&i, nid);
371 sreclaimable = node_page_state(pgdat, NR_SLAB_RECLAIMABLE);
372 sunreclaimable = node_page_state(pgdat, NR_SLAB_UNRECLAIMABLE);
373 n = sprintf(buf,
374 "Node %d MemTotal: %8lu kB\n"
375 "Node %d MemFree: %8lu kB\n"
376 "Node %d MemUsed: %8lu kB\n"
377 "Node %d Active: %8lu kB\n"
378 "Node %d Inactive: %8lu kB\n"
379 "Node %d Active(anon): %8lu kB\n"
380 "Node %d Inactive(anon): %8lu kB\n"
381 "Node %d Active(file): %8lu kB\n"
382 "Node %d Inactive(file): %8lu kB\n"
383 "Node %d Unevictable: %8lu kB\n"
384 "Node %d Mlocked: %8lu kB\n",
385 nid, K(i.totalram),
386 nid, K(i.freeram),
387 nid, K(i.totalram - i.freeram),
388 nid, K(node_page_state(pgdat, NR_ACTIVE_ANON) +
389 node_page_state(pgdat, NR_ACTIVE_FILE)),
390 nid, K(node_page_state(pgdat, NR_INACTIVE_ANON) +
391 node_page_state(pgdat, NR_INACTIVE_FILE)),
392 nid, K(node_page_state(pgdat, NR_ACTIVE_ANON)),
393 nid, K(node_page_state(pgdat, NR_INACTIVE_ANON)),
394 nid, K(node_page_state(pgdat, NR_ACTIVE_FILE)),
395 nid, K(node_page_state(pgdat, NR_INACTIVE_FILE)),
396 nid, K(node_page_state(pgdat, NR_UNEVICTABLE)),
397 nid, K(sum_zone_node_page_state(nid, NR_MLOCK)));
398
399#ifdef CONFIG_HIGHMEM
400 n += sprintf(buf + n,
401 "Node %d HighTotal: %8lu kB\n"
402 "Node %d HighFree: %8lu kB\n"
403 "Node %d LowTotal: %8lu kB\n"
404 "Node %d LowFree: %8lu kB\n",
405 nid, K(i.totalhigh),
406 nid, K(i.freehigh),
407 nid, K(i.totalram - i.totalhigh),
408 nid, K(i.freeram - i.freehigh));
409#endif
410 n += sprintf(buf + n,
411 "Node %d Dirty: %8lu kB\n"
412 "Node %d Writeback: %8lu kB\n"
413 "Node %d FilePages: %8lu kB\n"
414 "Node %d Mapped: %8lu kB\n"
415 "Node %d AnonPages: %8lu kB\n"
416 "Node %d Shmem: %8lu kB\n"
417 "Node %d KernelStack: %8lu kB\n"
418#ifdef CONFIG_SHADOW_CALL_STACK
419 "Node %d ShadowCallStack:%8lu kB\n"
420#endif
421 "Node %d PageTables: %8lu kB\n"
422 "Node %d NFS_Unstable: %8lu kB\n"
423 "Node %d Bounce: %8lu kB\n"
424 "Node %d WritebackTmp: %8lu kB\n"
425 "Node %d KReclaimable: %8lu kB\n"
426 "Node %d Slab: %8lu kB\n"
427 "Node %d SReclaimable: %8lu kB\n"
428 "Node %d SUnreclaim: %8lu kB\n"
429#ifdef CONFIG_TRANSPARENT_HUGEPAGE
430 "Node %d AnonHugePages: %8lu kB\n"
431 "Node %d ShmemHugePages: %8lu kB\n"
432 "Node %d ShmemPmdMapped: %8lu kB\n"
433 "Node %d FileHugePages: %8lu kB\n"
434 "Node %d FilePmdMapped: %8lu kB\n"
435#endif
436 ,
437 nid, K(node_page_state(pgdat, NR_FILE_DIRTY)),
438 nid, K(node_page_state(pgdat, NR_WRITEBACK)),
439 nid, K(node_page_state(pgdat, NR_FILE_PAGES)),
440 nid, K(node_page_state(pgdat, NR_FILE_MAPPED)),
441 nid, K(node_page_state(pgdat, NR_ANON_MAPPED)),
442 nid, K(i.sharedram),
443 nid, sum_zone_node_page_state(nid, NR_KERNEL_STACK_KB),
444#ifdef CONFIG_SHADOW_CALL_STACK
445 nid, sum_zone_node_page_state(nid, NR_KERNEL_SCS_KB),
446#endif
447 nid, K(sum_zone_node_page_state(nid, NR_PAGETABLE)),
448 nid, 0UL,
449 nid, K(sum_zone_node_page_state(nid, NR_BOUNCE)),
450 nid, K(node_page_state(pgdat, NR_WRITEBACK_TEMP)),
451 nid, K(sreclaimable +
452 node_page_state(pgdat, NR_KERNEL_MISC_RECLAIMABLE)),
453 nid, K(sreclaimable + sunreclaimable),
454 nid, K(sreclaimable),
455 nid, K(sunreclaimable)
456#ifdef CONFIG_TRANSPARENT_HUGEPAGE
457 ,
458 nid, K(node_page_state(pgdat, NR_ANON_THPS) *
459 HPAGE_PMD_NR),
460 nid, K(node_page_state(pgdat, NR_SHMEM_THPS) *
461 HPAGE_PMD_NR),
462 nid, K(node_page_state(pgdat, NR_SHMEM_PMDMAPPED) *
463 HPAGE_PMD_NR),
464 nid, K(node_page_state(pgdat, NR_FILE_THPS) *
465 HPAGE_PMD_NR),
466 nid, K(node_page_state(pgdat, NR_FILE_PMDMAPPED) *
467 HPAGE_PMD_NR)
468#endif
469 );
470 n += hugetlb_report_node_meminfo(nid, buf + n);
471 return n;
472}
473
474#undef K
475static DEVICE_ATTR(meminfo, S_IRUGO, node_read_meminfo, NULL);
476
477static ssize_t node_read_numastat(struct device *dev,
478 struct device_attribute *attr, char *buf)
479{
480 return sprintf(buf,
481 "numa_hit %lu\n"
482 "numa_miss %lu\n"
483 "numa_foreign %lu\n"
484 "interleave_hit %lu\n"
485 "local_node %lu\n"
486 "other_node %lu\n",
487 sum_zone_numa_state(dev->id, NUMA_HIT),
488 sum_zone_numa_state(dev->id, NUMA_MISS),
489 sum_zone_numa_state(dev->id, NUMA_FOREIGN),
490 sum_zone_numa_state(dev->id, NUMA_INTERLEAVE_HIT),
491 sum_zone_numa_state(dev->id, NUMA_LOCAL),
492 sum_zone_numa_state(dev->id, NUMA_OTHER));
493}
494static DEVICE_ATTR(numastat, S_IRUGO, node_read_numastat, NULL);
495
496static ssize_t node_read_vmstat(struct device *dev,
497 struct device_attribute *attr, char *buf)
498{
499 int nid = dev->id;
500 struct pglist_data *pgdat = NODE_DATA(nid);
501 int i;
502 int n = 0;
503
504 for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)
505 n += sprintf(buf+n, "%s %lu\n", zone_stat_name(i),
506 sum_zone_node_page_state(nid, i));
507
508#ifdef CONFIG_NUMA
509 for (i = 0; i < NR_VM_NUMA_STAT_ITEMS; i++)
510 n += sprintf(buf+n, "%s %lu\n", numa_stat_name(i),
511 sum_zone_numa_state(nid, i));
512#endif
513
514 for (i = 0; i < NR_VM_NODE_STAT_ITEMS; i++)
515 n += sprintf(buf+n, "%s %lu\n", node_stat_name(i),
516 node_page_state(pgdat, i));
517
518 return n;
519}
520static DEVICE_ATTR(vmstat, S_IRUGO, node_read_vmstat, NULL);
521
522static ssize_t node_read_distance(struct device *dev,
523 struct device_attribute *attr, char *buf)
524{
525 int nid = dev->id;
526 int len = 0;
527 int i;
528
529 /*
530 * buf is currently PAGE_SIZE in length and each node needs 4 chars
531 * at the most (distance + space or newline).
532 */
533 BUILD_BUG_ON(MAX_NUMNODES * 4 > PAGE_SIZE);
534
535 for_each_online_node(i)
536 len += sprintf(buf + len, "%s%d", i ? " " : "", node_distance(nid, i));
537
538 len += sprintf(buf + len, "\n");
539 return len;
540}
541static DEVICE_ATTR(distance, S_IRUGO, node_read_distance, NULL);
542
543static struct attribute *node_dev_attrs[] = {
544 &dev_attr_cpumap.attr,
545 &dev_attr_cpulist.attr,
546 &dev_attr_meminfo.attr,
547 &dev_attr_numastat.attr,
548 &dev_attr_distance.attr,
549 &dev_attr_vmstat.attr,
550 NULL
551};
552ATTRIBUTE_GROUPS(node_dev);
553
554#ifdef CONFIG_HUGETLBFS
555/*
556 * hugetlbfs per node attributes registration interface:
557 * When/if hugetlb[fs] subsystem initializes [sometime after this module],
558 * it will register its per node attributes for all online nodes with
559 * memory. It will also call register_hugetlbfs_with_node(), below, to
560 * register its attribute registration functions with this node driver.
561 * Once these hooks have been initialized, the node driver will call into
562 * the hugetlb module to [un]register attributes for hot-plugged nodes.
563 */
564static node_registration_func_t __hugetlb_register_node;
565static node_registration_func_t __hugetlb_unregister_node;
566
567static inline bool hugetlb_register_node(struct node *node)
568{
569 if (__hugetlb_register_node &&
570 node_state(node->dev.id, N_MEMORY)) {
571 __hugetlb_register_node(node);
572 return true;
573 }
574 return false;
575}
576
577static inline void hugetlb_unregister_node(struct node *node)
578{
579 if (__hugetlb_unregister_node)
580 __hugetlb_unregister_node(node);
581}
582
583void register_hugetlbfs_with_node(node_registration_func_t doregister,
584 node_registration_func_t unregister)
585{
586 __hugetlb_register_node = doregister;
587 __hugetlb_unregister_node = unregister;
588}
589#else
590static inline void hugetlb_register_node(struct node *node) {}
591
592static inline void hugetlb_unregister_node(struct node *node) {}
593#endif
594
595static void node_device_release(struct device *dev)
596{
597 struct node *node = to_node(dev);
598
599#if defined(CONFIG_MEMORY_HOTPLUG_SPARSE) && defined(CONFIG_HUGETLBFS)
600 /*
601 * We schedule the work only when a memory section is
602 * onlined/offlined on this node. When we come here,
603 * all the memory on this node has been offlined,
604 * so we won't enqueue new work to this work.
605 *
606 * The work is using node->node_work, so we should
607 * flush work before freeing the memory.
608 */
609 flush_work(&node->node_work);
610#endif
611 kfree(node);
612}
613
614/*
615 * register_node - Setup a sysfs device for a node.
616 * @num - Node number to use when creating the device.
617 *
618 * Initialize and register the node device.
619 */
620static int register_node(struct node *node, int num)
621{
622 int error;
623
624 node->dev.id = num;
625 node->dev.bus = &node_subsys;
626 node->dev.release = node_device_release;
627 node->dev.groups = node_dev_groups;
628 error = device_register(&node->dev);
629
630 if (error)
631 put_device(&node->dev);
632 else {
633 hugetlb_register_node(node);
634
635 compaction_register_node(node);
636 }
637 return error;
638}
639
640/**
641 * unregister_node - unregister a node device
642 * @node: node going away
643 *
644 * Unregisters a node device @node. All the devices on the node must be
645 * unregistered before calling this function.
646 */
647void unregister_node(struct node *node)
648{
649 hugetlb_unregister_node(node); /* no-op, if memoryless node */
650 node_remove_accesses(node);
651 node_remove_caches(node);
652 device_unregister(&node->dev);
653}
654
655struct node *node_devices[MAX_NUMNODES];
656
657/*
658 * register cpu under node
659 */
660int register_cpu_under_node(unsigned int cpu, unsigned int nid)
661{
662 int ret;
663 struct device *obj;
664
665 if (!node_online(nid))
666 return 0;
667
668 obj = get_cpu_device(cpu);
669 if (!obj)
670 return 0;
671
672 ret = sysfs_create_link(&node_devices[nid]->dev.kobj,
673 &obj->kobj,
674 kobject_name(&obj->kobj));
675 if (ret)
676 return ret;
677
678 return sysfs_create_link(&obj->kobj,
679 &node_devices[nid]->dev.kobj,
680 kobject_name(&node_devices[nid]->dev.kobj));
681}
682
683/**
684 * register_memory_node_under_compute_node - link memory node to its compute
685 * node for a given access class.
686 * @mem_nid: Memory node number
687 * @cpu_nid: Cpu node number
688 * @access: Access class to register
689 *
690 * Description:
691 * For use with platforms that may have separate memory and compute nodes.
692 * This function will export node relationships linking which memory
693 * initiator nodes can access memory targets at a given ranked access
694 * class.
695 */
696int register_memory_node_under_compute_node(unsigned int mem_nid,
697 unsigned int cpu_nid,
698 unsigned access)
699{
700 struct node *init_node, *targ_node;
701 struct node_access_nodes *initiator, *target;
702 int ret;
703
704 if (!node_online(cpu_nid) || !node_online(mem_nid))
705 return -ENODEV;
706
707 init_node = node_devices[cpu_nid];
708 targ_node = node_devices[mem_nid];
709 initiator = node_init_node_access(init_node, access);
710 target = node_init_node_access(targ_node, access);
711 if (!initiator || !target)
712 return -ENOMEM;
713
714 ret = sysfs_add_link_to_group(&initiator->dev.kobj, "targets",
715 &targ_node->dev.kobj,
716 dev_name(&targ_node->dev));
717 if (ret)
718 return ret;
719
720 ret = sysfs_add_link_to_group(&target->dev.kobj, "initiators",
721 &init_node->dev.kobj,
722 dev_name(&init_node->dev));
723 if (ret)
724 goto err;
725
726 return 0;
727 err:
728 sysfs_remove_link_from_group(&initiator->dev.kobj, "targets",
729 dev_name(&targ_node->dev));
730 return ret;
731}
732
733int unregister_cpu_under_node(unsigned int cpu, unsigned int nid)
734{
735 struct device *obj;
736
737 if (!node_online(nid))
738 return 0;
739
740 obj = get_cpu_device(cpu);
741 if (!obj)
742 return 0;
743
744 sysfs_remove_link(&node_devices[nid]->dev.kobj,
745 kobject_name(&obj->kobj));
746 sysfs_remove_link(&obj->kobj,
747 kobject_name(&node_devices[nid]->dev.kobj));
748
749 return 0;
750}
751
752#ifdef CONFIG_MEMORY_HOTPLUG_SPARSE
753static int __ref get_nid_for_pfn(unsigned long pfn)
754{
755 if (!pfn_valid_within(pfn))
756 return -1;
757#ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
758 if (system_state < SYSTEM_RUNNING)
759 return early_pfn_to_nid(pfn);
760#endif
761 return pfn_to_nid(pfn);
762}
763
764/* register memory section under specified node if it spans that node */
765static int register_mem_sect_under_node(struct memory_block *mem_blk,
766 void *arg)
767{
768 unsigned long memory_block_pfns = memory_block_size_bytes() / PAGE_SIZE;
769 unsigned long start_pfn = section_nr_to_pfn(mem_blk->start_section_nr);
770 unsigned long end_pfn = start_pfn + memory_block_pfns - 1;
771 int ret, nid = *(int *)arg;
772 unsigned long pfn;
773
774 for (pfn = start_pfn; pfn <= end_pfn; pfn++) {
775 int page_nid;
776
777 /*
778 * memory block could have several absent sections from start.
779 * skip pfn range from absent section
780 */
781 if (!pfn_in_present_section(pfn)) {
782 pfn = round_down(pfn + PAGES_PER_SECTION,
783 PAGES_PER_SECTION) - 1;
784 continue;
785 }
786
787 /*
788 * We need to check if page belongs to nid only for the boot
789 * case, during hotplug we know that all pages in the memory
790 * block belong to the same node.
791 */
792 if (system_state == SYSTEM_BOOTING) {
793 page_nid = get_nid_for_pfn(pfn);
794 if (page_nid < 0)
795 continue;
796 if (page_nid != nid)
797 continue;
798 }
799
800 /*
801 * If this memory block spans multiple nodes, we only indicate
802 * the last processed node.
803 */
804 mem_blk->nid = nid;
805
806 ret = sysfs_create_link_nowarn(&node_devices[nid]->dev.kobj,
807 &mem_blk->dev.kobj,
808 kobject_name(&mem_blk->dev.kobj));
809 if (ret)
810 return ret;
811
812 return sysfs_create_link_nowarn(&mem_blk->dev.kobj,
813 &node_devices[nid]->dev.kobj,
814 kobject_name(&node_devices[nid]->dev.kobj));
815 }
816 /* mem section does not span the specified node */
817 return 0;
818}
819
820/*
821 * Unregister a memory block device under the node it spans. Memory blocks
822 * with multiple nodes cannot be offlined and therefore also never be removed.
823 */
824void unregister_memory_block_under_nodes(struct memory_block *mem_blk)
825{
826 if (mem_blk->nid == NUMA_NO_NODE)
827 return;
828
829 sysfs_remove_link(&node_devices[mem_blk->nid]->dev.kobj,
830 kobject_name(&mem_blk->dev.kobj));
831 sysfs_remove_link(&mem_blk->dev.kobj,
832 kobject_name(&node_devices[mem_blk->nid]->dev.kobj));
833}
834
835int link_mem_sections(int nid, unsigned long start_pfn, unsigned long end_pfn)
836{
837 return walk_memory_blocks(PFN_PHYS(start_pfn),
838 PFN_PHYS(end_pfn - start_pfn), (void *)&nid,
839 register_mem_sect_under_node);
840}
841
842#ifdef CONFIG_HUGETLBFS
843/*
844 * Handle per node hstate attribute [un]registration on transistions
845 * to/from memoryless state.
846 */
847static void node_hugetlb_work(struct work_struct *work)
848{
849 struct node *node = container_of(work, struct node, node_work);
850
851 /*
852 * We only get here when a node transitions to/from memoryless state.
853 * We can detect which transition occurred by examining whether the
854 * node has memory now. hugetlb_register_node() already check this
855 * so we try to register the attributes. If that fails, then the
856 * node has transitioned to memoryless, try to unregister the
857 * attributes.
858 */
859 if (!hugetlb_register_node(node))
860 hugetlb_unregister_node(node);
861}
862
863static void init_node_hugetlb_work(int nid)
864{
865 INIT_WORK(&node_devices[nid]->node_work, node_hugetlb_work);
866}
867
868static int node_memory_callback(struct notifier_block *self,
869 unsigned long action, void *arg)
870{
871 struct memory_notify *mnb = arg;
872 int nid = mnb->status_change_nid;
873
874 switch (action) {
875 case MEM_ONLINE:
876 case MEM_OFFLINE:
877 /*
878 * offload per node hstate [un]registration to a work thread
879 * when transitioning to/from memoryless state.
880 */
881 if (nid != NUMA_NO_NODE)
882 schedule_work(&node_devices[nid]->node_work);
883 break;
884
885 case MEM_GOING_ONLINE:
886 case MEM_GOING_OFFLINE:
887 case MEM_CANCEL_ONLINE:
888 case MEM_CANCEL_OFFLINE:
889 default:
890 break;
891 }
892
893 return NOTIFY_OK;
894}
895#endif /* CONFIG_HUGETLBFS */
896#endif /* CONFIG_MEMORY_HOTPLUG_SPARSE */
897
898#if !defined(CONFIG_MEMORY_HOTPLUG_SPARSE) || \
899 !defined(CONFIG_HUGETLBFS)
900static inline int node_memory_callback(struct notifier_block *self,
901 unsigned long action, void *arg)
902{
903 return NOTIFY_OK;
904}
905
906static void init_node_hugetlb_work(int nid) { }
907
908#endif
909
910int __register_one_node(int nid)
911{
912 int error;
913 int cpu;
914
915 node_devices[nid] = kzalloc(sizeof(struct node), GFP_KERNEL);
916 if (!node_devices[nid])
917 return -ENOMEM;
918
919 error = register_node(node_devices[nid], nid);
920
921 /* link cpu under this node */
922 for_each_present_cpu(cpu) {
923 if (cpu_to_node(cpu) == nid)
924 register_cpu_under_node(cpu, nid);
925 }
926
927 INIT_LIST_HEAD(&node_devices[nid]->access_list);
928 /* initialize work queue for memory hot plug */
929 init_node_hugetlb_work(nid);
930 node_init_caches(nid);
931
932 return error;
933}
934
935void unregister_one_node(int nid)
936{
937 if (!node_devices[nid])
938 return;
939
940 unregister_node(node_devices[nid]);
941 node_devices[nid] = NULL;
942}
943
944/*
945 * node states attributes
946 */
947
948static ssize_t print_nodes_state(enum node_states state, char *buf)
949{
950 int n;
951
952 n = scnprintf(buf, PAGE_SIZE - 1, "%*pbl",
953 nodemask_pr_args(&node_states[state]));
954 buf[n++] = '\n';
955 buf[n] = '\0';
956 return n;
957}
958
959struct node_attr {
960 struct device_attribute attr;
961 enum node_states state;
962};
963
964static ssize_t show_node_state(struct device *dev,
965 struct device_attribute *attr, char *buf)
966{
967 struct node_attr *na = container_of(attr, struct node_attr, attr);
968 return print_nodes_state(na->state, buf);
969}
970
971#define _NODE_ATTR(name, state) \
972 { __ATTR(name, 0444, show_node_state, NULL), state }
973
974static struct node_attr node_state_attr[] = {
975 [N_POSSIBLE] = _NODE_ATTR(possible, N_POSSIBLE),
976 [N_ONLINE] = _NODE_ATTR(online, N_ONLINE),
977 [N_NORMAL_MEMORY] = _NODE_ATTR(has_normal_memory, N_NORMAL_MEMORY),
978#ifdef CONFIG_HIGHMEM
979 [N_HIGH_MEMORY] = _NODE_ATTR(has_high_memory, N_HIGH_MEMORY),
980#endif
981 [N_MEMORY] = _NODE_ATTR(has_memory, N_MEMORY),
982 [N_CPU] = _NODE_ATTR(has_cpu, N_CPU),
983};
984
985static struct attribute *node_state_attrs[] = {
986 &node_state_attr[N_POSSIBLE].attr.attr,
987 &node_state_attr[N_ONLINE].attr.attr,
988 &node_state_attr[N_NORMAL_MEMORY].attr.attr,
989#ifdef CONFIG_HIGHMEM
990 &node_state_attr[N_HIGH_MEMORY].attr.attr,
991#endif
992 &node_state_attr[N_MEMORY].attr.attr,
993 &node_state_attr[N_CPU].attr.attr,
994 NULL
995};
996
997static struct attribute_group memory_root_attr_group = {
998 .attrs = node_state_attrs,
999};
1000
1001static const struct attribute_group *cpu_root_attr_groups[] = {
1002 &memory_root_attr_group,
1003 NULL,
1004};
1005
1006#define NODE_CALLBACK_PRI 2 /* lower than SLAB */
1007static int __init register_node_type(void)
1008{
1009 int ret;
1010
1011 BUILD_BUG_ON(ARRAY_SIZE(node_state_attr) != NR_NODE_STATES);
1012 BUILD_BUG_ON(ARRAY_SIZE(node_state_attrs)-1 != NR_NODE_STATES);
1013
1014 ret = subsys_system_register(&node_subsys, cpu_root_attr_groups);
1015 if (!ret) {
1016 static struct notifier_block node_memory_callback_nb = {
1017 .notifier_call = node_memory_callback,
1018 .priority = NODE_CALLBACK_PRI,
1019 };
1020 register_hotmemory_notifier(&node_memory_callback_nb);
1021 }
1022
1023 /*
1024 * Note: we're not going to unregister the node class if we fail
1025 * to register the node state class attribute files.
1026 */
1027 return ret;
1028}
1029postcore_initcall(register_node_type);