xref: /linux/drivers/base/node.c (revision ab93e0dd72c37d378dd936f031ffb83ff2bd87ce)
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/mempolicy.h>
11 #include <linux/vmstat.h>
12 #include <linux/notifier.h>
13 #include <linux/node.h>
14 #include <linux/hugetlb.h>
15 #include <linux/compaction.h>
16 #include <linux/cpumask.h>
17 #include <linux/topology.h>
18 #include <linux/nodemask.h>
19 #include <linux/cpu.h>
20 #include <linux/device.h>
21 #include <linux/pm_runtime.h>
22 #include <linux/swap.h>
23 #include <linux/slab.h>
24 #include <linux/memblock.h>
25 
26 static const struct bus_type node_subsys = {
27 	.name = "node",
28 	.dev_name = "node",
29 };
30 
cpumap_read(struct file * file,struct kobject * kobj,const struct bin_attribute * attr,char * buf,loff_t off,size_t count)31 static inline ssize_t cpumap_read(struct file *file, struct kobject *kobj,
32 				  const struct bin_attribute *attr, char *buf,
33 				  loff_t off, size_t count)
34 {
35 	struct device *dev = kobj_to_dev(kobj);
36 	struct node *node_dev = to_node(dev);
37 	cpumask_var_t mask;
38 	ssize_t n;
39 
40 	if (!alloc_cpumask_var(&mask, GFP_KERNEL))
41 		return 0;
42 
43 	cpumask_and(mask, cpumask_of_node(node_dev->dev.id), cpu_online_mask);
44 	n = cpumap_print_bitmask_to_buf(buf, mask, off, count);
45 	free_cpumask_var(mask);
46 
47 	return n;
48 }
49 
50 static const BIN_ATTR_RO(cpumap, CPUMAP_FILE_MAX_BYTES);
51 
cpulist_read(struct file * file,struct kobject * kobj,const struct bin_attribute * attr,char * buf,loff_t off,size_t count)52 static inline ssize_t cpulist_read(struct file *file, struct kobject *kobj,
53 				   const struct bin_attribute *attr, char *buf,
54 				   loff_t off, size_t count)
55 {
56 	struct device *dev = kobj_to_dev(kobj);
57 	struct node *node_dev = to_node(dev);
58 	cpumask_var_t mask;
59 	ssize_t n;
60 
61 	if (!alloc_cpumask_var(&mask, GFP_KERNEL))
62 		return 0;
63 
64 	cpumask_and(mask, cpumask_of_node(node_dev->dev.id), cpu_online_mask);
65 	n = cpumap_print_list_to_buf(buf, mask, off, count);
66 	free_cpumask_var(mask);
67 
68 	return n;
69 }
70 
71 static const BIN_ATTR_RO(cpulist, CPULIST_FILE_MAX_BYTES);
72 
73 /**
74  * struct node_access_nodes - Access class device to hold user visible
75  * 			      relationships to other nodes.
76  * @dev:	Device for this memory access class
77  * @list_node:	List element in the node's access list
78  * @access:	The access class rank
79  * @coord:	Heterogeneous memory performance coordinates
80  */
81 struct node_access_nodes {
82 	struct device		dev;
83 	struct list_head	list_node;
84 	unsigned int		access;
85 #ifdef CONFIG_HMEM_REPORTING
86 	struct access_coordinate	coord;
87 #endif
88 };
89 #define to_access_nodes(dev) container_of(dev, struct node_access_nodes, dev)
90 
91 static struct attribute *node_init_access_node_attrs[] = {
92 	NULL,
93 };
94 
95 static struct attribute *node_targ_access_node_attrs[] = {
96 	NULL,
97 };
98 
99 static const struct attribute_group initiators = {
100 	.name	= "initiators",
101 	.attrs	= node_init_access_node_attrs,
102 };
103 
104 static const struct attribute_group targets = {
105 	.name	= "targets",
106 	.attrs	= node_targ_access_node_attrs,
107 };
108 
109 static const struct attribute_group *node_access_node_groups[] = {
110 	&initiators,
111 	&targets,
112 	NULL,
113 };
114 
115 #ifdef CONFIG_MEMORY_HOTPLUG
116 static BLOCKING_NOTIFIER_HEAD(node_chain);
117 
register_node_notifier(struct notifier_block * nb)118 int register_node_notifier(struct notifier_block *nb)
119 {
120 	return blocking_notifier_chain_register(&node_chain, nb);
121 }
122 EXPORT_SYMBOL(register_node_notifier);
123 
unregister_node_notifier(struct notifier_block * nb)124 void unregister_node_notifier(struct notifier_block *nb)
125 {
126 	blocking_notifier_chain_unregister(&node_chain, nb);
127 }
128 EXPORT_SYMBOL(unregister_node_notifier);
129 
node_notify(unsigned long val,void * v)130 int node_notify(unsigned long val, void *v)
131 {
132 	return blocking_notifier_call_chain(&node_chain, val, v);
133 }
134 #endif
135 
node_remove_accesses(struct node * node)136 static void node_remove_accesses(struct node *node)
137 {
138 	struct node_access_nodes *c, *cnext;
139 
140 	list_for_each_entry_safe(c, cnext, &node->access_list, list_node) {
141 		list_del(&c->list_node);
142 		device_unregister(&c->dev);
143 	}
144 }
145 
node_access_release(struct device * dev)146 static void node_access_release(struct device *dev)
147 {
148 	kfree(to_access_nodes(dev));
149 }
150 
node_init_node_access(struct node * node,enum access_coordinate_class access)151 static struct node_access_nodes *node_init_node_access(struct node *node,
152 						       enum access_coordinate_class access)
153 {
154 	struct node_access_nodes *access_node;
155 	struct device *dev;
156 
157 	list_for_each_entry(access_node, &node->access_list, list_node)
158 		if (access_node->access == access)
159 			return access_node;
160 
161 	access_node = kzalloc(sizeof(*access_node), GFP_KERNEL);
162 	if (!access_node)
163 		return NULL;
164 
165 	access_node->access = access;
166 	dev = &access_node->dev;
167 	dev->parent = &node->dev;
168 	dev->release = node_access_release;
169 	dev->groups = node_access_node_groups;
170 	if (dev_set_name(dev, "access%u", access))
171 		goto free;
172 
173 	if (device_register(dev))
174 		goto free_name;
175 
176 	pm_runtime_no_callbacks(dev);
177 	list_add_tail(&access_node->list_node, &node->access_list);
178 	return access_node;
179 free_name:
180 	kfree_const(dev->kobj.name);
181 free:
182 	kfree(access_node);
183 	return NULL;
184 }
185 
186 #ifdef CONFIG_HMEM_REPORTING
187 #define ACCESS_ATTR(property)						\
188 static ssize_t property##_show(struct device *dev,			\
189 			   struct device_attribute *attr,		\
190 			   char *buf)					\
191 {									\
192 	return sysfs_emit(buf, "%u\n",					\
193 			  to_access_nodes(dev)->coord.property);	\
194 }									\
195 static DEVICE_ATTR_RO(property)
196 
197 ACCESS_ATTR(read_bandwidth);
198 ACCESS_ATTR(read_latency);
199 ACCESS_ATTR(write_bandwidth);
200 ACCESS_ATTR(write_latency);
201 
202 static struct attribute *access_attrs[] = {
203 	&dev_attr_read_bandwidth.attr,
204 	&dev_attr_read_latency.attr,
205 	&dev_attr_write_bandwidth.attr,
206 	&dev_attr_write_latency.attr,
207 	NULL,
208 };
209 
210 /**
211  * node_set_perf_attrs - Set the performance values for given access class
212  * @nid: Node identifier to be set
213  * @coord: Heterogeneous memory performance coordinates
214  * @access: The access class the for the given attributes
215  */
node_set_perf_attrs(unsigned int nid,struct access_coordinate * coord,enum access_coordinate_class access)216 void node_set_perf_attrs(unsigned int nid, struct access_coordinate *coord,
217 			 enum access_coordinate_class access)
218 {
219 	struct node_access_nodes *c;
220 	struct node *node;
221 	int i;
222 
223 	if (WARN_ON_ONCE(!node_online(nid)))
224 		return;
225 
226 	node = node_devices[nid];
227 	c = node_init_node_access(node, access);
228 	if (!c)
229 		return;
230 
231 	c->coord = *coord;
232 	for (i = 0; access_attrs[i] != NULL; i++) {
233 		if (sysfs_add_file_to_group(&c->dev.kobj, access_attrs[i],
234 					    "initiators")) {
235 			pr_info("failed to add performance attribute to node %d\n",
236 				nid);
237 			break;
238 		}
239 	}
240 
241 	/* When setting CPU access coordinates, update mempolicy */
242 	if (access == ACCESS_COORDINATE_CPU) {
243 		if (mempolicy_set_node_perf(nid, coord)) {
244 			pr_info("failed to set mempolicy attrs for node %d\n",
245 				nid);
246 		}
247 	}
248 }
249 EXPORT_SYMBOL_GPL(node_set_perf_attrs);
250 
251 /**
252  * struct node_cache_info - Internal tracking for memory node caches
253  * @dev:	Device represeting the cache level
254  * @node:	List element for tracking in the node
255  * @cache_attrs:Attributes for this cache level
256  */
257 struct node_cache_info {
258 	struct device dev;
259 	struct list_head node;
260 	struct node_cache_attrs cache_attrs;
261 };
262 #define to_cache_info(device) container_of(device, struct node_cache_info, dev)
263 
264 #define CACHE_ATTR(name, fmt) 						\
265 static ssize_t name##_show(struct device *dev,				\
266 			   struct device_attribute *attr,		\
267 			   char *buf)					\
268 {									\
269 	return sysfs_emit(buf, fmt "\n",				\
270 			  to_cache_info(dev)->cache_attrs.name);	\
271 }									\
272 static DEVICE_ATTR_RO(name);
273 
274 CACHE_ATTR(size, "%llu")
275 CACHE_ATTR(line_size, "%u")
276 CACHE_ATTR(indexing, "%u")
277 CACHE_ATTR(write_policy, "%u")
278 CACHE_ATTR(address_mode, "%#x")
279 
280 static struct attribute *cache_attrs[] = {
281 	&dev_attr_indexing.attr,
282 	&dev_attr_size.attr,
283 	&dev_attr_line_size.attr,
284 	&dev_attr_write_policy.attr,
285 	&dev_attr_address_mode.attr,
286 	NULL,
287 };
288 ATTRIBUTE_GROUPS(cache);
289 
node_cache_release(struct device * dev)290 static void node_cache_release(struct device *dev)
291 {
292 	kfree(dev);
293 }
294 
node_cacheinfo_release(struct device * dev)295 static void node_cacheinfo_release(struct device *dev)
296 {
297 	struct node_cache_info *info = to_cache_info(dev);
298 	kfree(info);
299 }
300 
node_init_cache_dev(struct node * node)301 static void node_init_cache_dev(struct node *node)
302 {
303 	struct device *dev;
304 
305 	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
306 	if (!dev)
307 		return;
308 
309 	device_initialize(dev);
310 	dev->parent = &node->dev;
311 	dev->release = node_cache_release;
312 	if (dev_set_name(dev, "memory_side_cache"))
313 		goto put_device;
314 
315 	if (device_add(dev))
316 		goto put_device;
317 
318 	pm_runtime_no_callbacks(dev);
319 	node->cache_dev = dev;
320 	return;
321 put_device:
322 	put_device(dev);
323 }
324 
325 /**
326  * node_add_cache() - add cache attribute to a memory node
327  * @nid: Node identifier that has new cache attributes
328  * @cache_attrs: Attributes for the cache being added
329  */
node_add_cache(unsigned int nid,struct node_cache_attrs * cache_attrs)330 void node_add_cache(unsigned int nid, struct node_cache_attrs *cache_attrs)
331 {
332 	struct node_cache_info *info;
333 	struct device *dev;
334 	struct node *node;
335 
336 	if (!node_online(nid) || !node_devices[nid])
337 		return;
338 
339 	node = node_devices[nid];
340 	list_for_each_entry(info, &node->cache_attrs, node) {
341 		if (info->cache_attrs.level == cache_attrs->level) {
342 			dev_warn(&node->dev,
343 				"attempt to add duplicate cache level:%d\n",
344 				cache_attrs->level);
345 			return;
346 		}
347 	}
348 
349 	if (!node->cache_dev)
350 		node_init_cache_dev(node);
351 	if (!node->cache_dev)
352 		return;
353 
354 	info = kzalloc(sizeof(*info), GFP_KERNEL);
355 	if (!info)
356 		return;
357 
358 	dev = &info->dev;
359 	device_initialize(dev);
360 	dev->parent = node->cache_dev;
361 	dev->release = node_cacheinfo_release;
362 	dev->groups = cache_groups;
363 	if (dev_set_name(dev, "index%d", cache_attrs->level))
364 		goto put_device;
365 
366 	info->cache_attrs = *cache_attrs;
367 	if (device_add(dev)) {
368 		dev_warn(&node->dev, "failed to add cache level:%d\n",
369 			 cache_attrs->level);
370 		goto put_device;
371 	}
372 	pm_runtime_no_callbacks(dev);
373 	list_add_tail(&info->node, &node->cache_attrs);
374 	return;
375 put_device:
376 	put_device(dev);
377 }
378 
node_remove_caches(struct node * node)379 static void node_remove_caches(struct node *node)
380 {
381 	struct node_cache_info *info, *next;
382 
383 	if (!node->cache_dev)
384 		return;
385 
386 	list_for_each_entry_safe(info, next, &node->cache_attrs, node) {
387 		list_del(&info->node);
388 		device_unregister(&info->dev);
389 	}
390 	device_unregister(node->cache_dev);
391 }
392 
node_init_caches(unsigned int nid)393 static void node_init_caches(unsigned int nid)
394 {
395 	INIT_LIST_HEAD(&node_devices[nid]->cache_attrs);
396 }
397 #else
node_init_caches(unsigned int nid)398 static void node_init_caches(unsigned int nid) { }
node_remove_caches(struct node * node)399 static void node_remove_caches(struct node *node) { }
400 #endif
401 
402 #define K(x) ((x) << (PAGE_SHIFT - 10))
node_read_meminfo(struct device * dev,struct device_attribute * attr,char * buf)403 static ssize_t node_read_meminfo(struct device *dev,
404 			struct device_attribute *attr, char *buf)
405 {
406 	int len = 0;
407 	int nid = dev->id;
408 	struct pglist_data *pgdat = NODE_DATA(nid);
409 	struct sysinfo i;
410 	unsigned long sreclaimable, sunreclaimable;
411 	unsigned long swapcached = 0;
412 
413 	si_meminfo_node(&i, nid);
414 	sreclaimable = node_page_state_pages(pgdat, NR_SLAB_RECLAIMABLE_B);
415 	sunreclaimable = node_page_state_pages(pgdat, NR_SLAB_UNRECLAIMABLE_B);
416 #ifdef CONFIG_SWAP
417 	swapcached = node_page_state_pages(pgdat, NR_SWAPCACHE);
418 #endif
419 	len = sysfs_emit_at(buf, len,
420 			    "Node %d MemTotal:       %8lu kB\n"
421 			    "Node %d MemFree:        %8lu kB\n"
422 			    "Node %d MemUsed:        %8lu kB\n"
423 			    "Node %d SwapCached:     %8lu kB\n"
424 			    "Node %d Active:         %8lu kB\n"
425 			    "Node %d Inactive:       %8lu kB\n"
426 			    "Node %d Active(anon):   %8lu kB\n"
427 			    "Node %d Inactive(anon): %8lu kB\n"
428 			    "Node %d Active(file):   %8lu kB\n"
429 			    "Node %d Inactive(file): %8lu kB\n"
430 			    "Node %d Unevictable:    %8lu kB\n"
431 			    "Node %d Mlocked:        %8lu kB\n",
432 			    nid, K(i.totalram),
433 			    nid, K(i.freeram),
434 			    nid, K(i.totalram - i.freeram),
435 			    nid, K(swapcached),
436 			    nid, K(node_page_state(pgdat, NR_ACTIVE_ANON) +
437 				   node_page_state(pgdat, NR_ACTIVE_FILE)),
438 			    nid, K(node_page_state(pgdat, NR_INACTIVE_ANON) +
439 				   node_page_state(pgdat, NR_INACTIVE_FILE)),
440 			    nid, K(node_page_state(pgdat, NR_ACTIVE_ANON)),
441 			    nid, K(node_page_state(pgdat, NR_INACTIVE_ANON)),
442 			    nid, K(node_page_state(pgdat, NR_ACTIVE_FILE)),
443 			    nid, K(node_page_state(pgdat, NR_INACTIVE_FILE)),
444 			    nid, K(node_page_state(pgdat, NR_UNEVICTABLE)),
445 			    nid, K(sum_zone_node_page_state(nid, NR_MLOCK)));
446 
447 #ifdef CONFIG_HIGHMEM
448 	len += sysfs_emit_at(buf, len,
449 			     "Node %d HighTotal:      %8lu kB\n"
450 			     "Node %d HighFree:       %8lu kB\n"
451 			     "Node %d LowTotal:       %8lu kB\n"
452 			     "Node %d LowFree:        %8lu kB\n",
453 			     nid, K(i.totalhigh),
454 			     nid, K(i.freehigh),
455 			     nid, K(i.totalram - i.totalhigh),
456 			     nid, K(i.freeram - i.freehigh));
457 #endif
458 	len += sysfs_emit_at(buf, len,
459 			     "Node %d Dirty:          %8lu kB\n"
460 			     "Node %d Writeback:      %8lu kB\n"
461 			     "Node %d FilePages:      %8lu kB\n"
462 			     "Node %d Mapped:         %8lu kB\n"
463 			     "Node %d AnonPages:      %8lu kB\n"
464 			     "Node %d Shmem:          %8lu kB\n"
465 			     "Node %d KernelStack:    %8lu kB\n"
466 #ifdef CONFIG_SHADOW_CALL_STACK
467 			     "Node %d ShadowCallStack:%8lu kB\n"
468 #endif
469 			     "Node %d PageTables:     %8lu kB\n"
470 			     "Node %d SecPageTables:  %8lu kB\n"
471 			     "Node %d NFS_Unstable:   %8lu kB\n"
472 			     "Node %d Bounce:         %8lu kB\n"
473 			     "Node %d WritebackTmp:   %8lu kB\n"
474 			     "Node %d KReclaimable:   %8lu kB\n"
475 			     "Node %d Slab:           %8lu kB\n"
476 			     "Node %d SReclaimable:   %8lu kB\n"
477 			     "Node %d SUnreclaim:     %8lu kB\n"
478 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
479 			     "Node %d AnonHugePages:  %8lu kB\n"
480 			     "Node %d ShmemHugePages: %8lu kB\n"
481 			     "Node %d ShmemPmdMapped: %8lu kB\n"
482 			     "Node %d FileHugePages:  %8lu kB\n"
483 			     "Node %d FilePmdMapped:  %8lu kB\n"
484 #endif
485 #ifdef CONFIG_UNACCEPTED_MEMORY
486 			     "Node %d Unaccepted:     %8lu kB\n"
487 #endif
488 			     ,
489 			     nid, K(node_page_state(pgdat, NR_FILE_DIRTY)),
490 			     nid, K(node_page_state(pgdat, NR_WRITEBACK)),
491 			     nid, K(node_page_state(pgdat, NR_FILE_PAGES)),
492 			     nid, K(node_page_state(pgdat, NR_FILE_MAPPED)),
493 			     nid, K(node_page_state(pgdat, NR_ANON_MAPPED)),
494 			     nid, K(i.sharedram),
495 			     nid, node_page_state(pgdat, NR_KERNEL_STACK_KB),
496 #ifdef CONFIG_SHADOW_CALL_STACK
497 			     nid, node_page_state(pgdat, NR_KERNEL_SCS_KB),
498 #endif
499 			     nid, K(node_page_state(pgdat, NR_PAGETABLE)),
500 			     nid, K(node_page_state(pgdat, NR_SECONDARY_PAGETABLE)),
501 			     nid, 0UL,
502 			     nid, 0UL,
503 			     nid, 0UL,
504 			     nid, K(sreclaimable +
505 				    node_page_state(pgdat, NR_KERNEL_MISC_RECLAIMABLE)),
506 			     nid, K(sreclaimable + sunreclaimable),
507 			     nid, K(sreclaimable),
508 			     nid, K(sunreclaimable)
509 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
510 			     ,
511 			     nid, K(node_page_state(pgdat, NR_ANON_THPS)),
512 			     nid, K(node_page_state(pgdat, NR_SHMEM_THPS)),
513 			     nid, K(node_page_state(pgdat, NR_SHMEM_PMDMAPPED)),
514 			     nid, K(node_page_state(pgdat, NR_FILE_THPS)),
515 			     nid, K(node_page_state(pgdat, NR_FILE_PMDMAPPED))
516 #endif
517 #ifdef CONFIG_UNACCEPTED_MEMORY
518 			     ,
519 			     nid, K(sum_zone_node_page_state(nid, NR_UNACCEPTED))
520 #endif
521 			    );
522 	len += hugetlb_report_node_meminfo(buf, len, nid);
523 	return len;
524 }
525 
526 #undef K
527 static DEVICE_ATTR(meminfo, 0444, node_read_meminfo, NULL);
528 
node_read_numastat(struct device * dev,struct device_attribute * attr,char * buf)529 static ssize_t node_read_numastat(struct device *dev,
530 				  struct device_attribute *attr, char *buf)
531 {
532 	fold_vm_numa_events();
533 	return sysfs_emit(buf,
534 			  "numa_hit %lu\n"
535 			  "numa_miss %lu\n"
536 			  "numa_foreign %lu\n"
537 			  "interleave_hit %lu\n"
538 			  "local_node %lu\n"
539 			  "other_node %lu\n",
540 			  sum_zone_numa_event_state(dev->id, NUMA_HIT),
541 			  sum_zone_numa_event_state(dev->id, NUMA_MISS),
542 			  sum_zone_numa_event_state(dev->id, NUMA_FOREIGN),
543 			  sum_zone_numa_event_state(dev->id, NUMA_INTERLEAVE_HIT),
544 			  sum_zone_numa_event_state(dev->id, NUMA_LOCAL),
545 			  sum_zone_numa_event_state(dev->id, NUMA_OTHER));
546 }
547 static DEVICE_ATTR(numastat, 0444, node_read_numastat, NULL);
548 
node_read_vmstat(struct device * dev,struct device_attribute * attr,char * buf)549 static ssize_t node_read_vmstat(struct device *dev,
550 				struct device_attribute *attr, char *buf)
551 {
552 	int nid = dev->id;
553 	struct pglist_data *pgdat = NODE_DATA(nid);
554 	int i;
555 	int len = 0;
556 
557 	for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)
558 		len += sysfs_emit_at(buf, len, "%s %lu\n",
559 				     zone_stat_name(i),
560 				     sum_zone_node_page_state(nid, i));
561 
562 #ifdef CONFIG_NUMA
563 	fold_vm_numa_events();
564 	for (i = 0; i < NR_VM_NUMA_EVENT_ITEMS; i++)
565 		len += sysfs_emit_at(buf, len, "%s %lu\n",
566 				     numa_stat_name(i),
567 				     sum_zone_numa_event_state(nid, i));
568 
569 #endif
570 	for (i = 0; i < NR_VM_NODE_STAT_ITEMS; i++) {
571 		unsigned long pages = node_page_state_pages(pgdat, i);
572 
573 		if (vmstat_item_print_in_thp(i))
574 			pages /= HPAGE_PMD_NR;
575 		len += sysfs_emit_at(buf, len, "%s %lu\n", node_stat_name(i),
576 				     pages);
577 	}
578 
579 	return len;
580 }
581 static DEVICE_ATTR(vmstat, 0444, node_read_vmstat, NULL);
582 
node_read_distance(struct device * dev,struct device_attribute * attr,char * buf)583 static ssize_t node_read_distance(struct device *dev,
584 				  struct device_attribute *attr, char *buf)
585 {
586 	int nid = dev->id;
587 	int len = 0;
588 	int i;
589 
590 	/*
591 	 * buf is currently PAGE_SIZE in length and each node needs 4 chars
592 	 * at the most (distance + space or newline).
593 	 */
594 	BUILD_BUG_ON(MAX_NUMNODES * 4 > PAGE_SIZE);
595 
596 	for_each_online_node(i) {
597 		len += sysfs_emit_at(buf, len, "%s%d",
598 				     i ? " " : "", node_distance(nid, i));
599 	}
600 
601 	len += sysfs_emit_at(buf, len, "\n");
602 	return len;
603 }
604 static DEVICE_ATTR(distance, 0444, node_read_distance, NULL);
605 
606 static struct attribute *node_dev_attrs[] = {
607 	&dev_attr_meminfo.attr,
608 	&dev_attr_numastat.attr,
609 	&dev_attr_distance.attr,
610 	&dev_attr_vmstat.attr,
611 	NULL
612 };
613 
614 static const struct bin_attribute *node_dev_bin_attrs[] = {
615 	&bin_attr_cpumap,
616 	&bin_attr_cpulist,
617 	NULL
618 };
619 
620 static const struct attribute_group node_dev_group = {
621 	.attrs = node_dev_attrs,
622 	.bin_attrs = node_dev_bin_attrs,
623 };
624 
625 static const struct attribute_group *node_dev_groups[] = {
626 	&node_dev_group,
627 #ifdef CONFIG_HAVE_ARCH_NODE_DEV_GROUP
628 	&arch_node_dev_group,
629 #endif
630 #ifdef CONFIG_MEMORY_FAILURE
631 	&memory_failure_attr_group,
632 #endif
633 	NULL
634 };
635 
node_device_release(struct device * dev)636 static void node_device_release(struct device *dev)
637 {
638 	kfree(to_node(dev));
639 }
640 
641 /*
642  * register_node - Setup a sysfs device for a node.
643  * @num - Node number to use when creating the device.
644  *
645  * Initialize and register the node device.
646  */
register_node(struct node * node,int num)647 static int register_node(struct node *node, int num)
648 {
649 	int error;
650 
651 	node->dev.id = num;
652 	node->dev.bus = &node_subsys;
653 	node->dev.release = node_device_release;
654 	node->dev.groups = node_dev_groups;
655 	error = device_register(&node->dev);
656 
657 	if (error) {
658 		put_device(&node->dev);
659 	} else {
660 		hugetlb_register_node(node);
661 		compaction_register_node(node);
662 		reclaim_register_node(node);
663 	}
664 
665 	return error;
666 }
667 
668 /**
669  * unregister_node - unregister a node device
670  * @node: node going away
671  *
672  * Unregisters a node device @node.  All the devices on the node must be
673  * unregistered before calling this function.
674  */
unregister_node(struct node * node)675 void unregister_node(struct node *node)
676 {
677 	hugetlb_unregister_node(node);
678 	compaction_unregister_node(node);
679 	reclaim_unregister_node(node);
680 	node_remove_accesses(node);
681 	node_remove_caches(node);
682 	device_unregister(&node->dev);
683 }
684 
685 struct node *node_devices[MAX_NUMNODES];
686 
687 /*
688  * register cpu under node
689  */
register_cpu_under_node(unsigned int cpu,unsigned int nid)690 int register_cpu_under_node(unsigned int cpu, unsigned int nid)
691 {
692 	int ret;
693 	struct device *obj;
694 
695 	if (!node_online(nid))
696 		return 0;
697 
698 	obj = get_cpu_device(cpu);
699 	if (!obj)
700 		return 0;
701 
702 	ret = sysfs_create_link(&node_devices[nid]->dev.kobj,
703 				&obj->kobj,
704 				kobject_name(&obj->kobj));
705 	if (ret)
706 		return ret;
707 
708 	return sysfs_create_link(&obj->kobj,
709 				 &node_devices[nid]->dev.kobj,
710 				 kobject_name(&node_devices[nid]->dev.kobj));
711 }
712 
713 /**
714  * register_memory_node_under_compute_node - link memory node to its compute
715  *					     node for a given access class.
716  * @mem_nid:	Memory node number
717  * @cpu_nid:	Cpu  node number
718  * @access:	Access class to register
719  *
720  * Description:
721  * 	For use with platforms that may have separate memory and compute nodes.
722  * 	This function will export node relationships linking which memory
723  * 	initiator nodes can access memory targets at a given ranked access
724  * 	class.
725  */
register_memory_node_under_compute_node(unsigned int mem_nid,unsigned int cpu_nid,enum access_coordinate_class access)726 int register_memory_node_under_compute_node(unsigned int mem_nid,
727 					    unsigned int cpu_nid,
728 					    enum access_coordinate_class access)
729 {
730 	struct node *init_node, *targ_node;
731 	struct node_access_nodes *initiator, *target;
732 	int ret;
733 
734 	if (!node_online(cpu_nid) || !node_online(mem_nid))
735 		return -ENODEV;
736 
737 	init_node = node_devices[cpu_nid];
738 	targ_node = node_devices[mem_nid];
739 	initiator = node_init_node_access(init_node, access);
740 	target = node_init_node_access(targ_node, access);
741 	if (!initiator || !target)
742 		return -ENOMEM;
743 
744 	ret = sysfs_add_link_to_group(&initiator->dev.kobj, "targets",
745 				      &targ_node->dev.kobj,
746 				      dev_name(&targ_node->dev));
747 	if (ret)
748 		return ret;
749 
750 	ret = sysfs_add_link_to_group(&target->dev.kobj, "initiators",
751 				      &init_node->dev.kobj,
752 				      dev_name(&init_node->dev));
753 	if (ret)
754 		goto err;
755 
756 	return 0;
757  err:
758 	sysfs_remove_link_from_group(&initiator->dev.kobj, "targets",
759 				     dev_name(&targ_node->dev));
760 	return ret;
761 }
762 
unregister_cpu_under_node(unsigned int cpu,unsigned int nid)763 int unregister_cpu_under_node(unsigned int cpu, unsigned int nid)
764 {
765 	struct device *obj;
766 
767 	if (!node_online(nid))
768 		return 0;
769 
770 	obj = get_cpu_device(cpu);
771 	if (!obj)
772 		return 0;
773 
774 	sysfs_remove_link(&node_devices[nid]->dev.kobj,
775 			  kobject_name(&obj->kobj));
776 	sysfs_remove_link(&obj->kobj,
777 			  kobject_name(&node_devices[nid]->dev.kobj));
778 
779 	return 0;
780 }
781 
782 #ifdef CONFIG_MEMORY_HOTPLUG
do_register_memory_block_under_node(int nid,struct memory_block * mem_blk,enum meminit_context context)783 static void do_register_memory_block_under_node(int nid,
784 						struct memory_block *mem_blk,
785 						enum meminit_context context)
786 {
787 	int ret;
788 
789 	memory_block_add_nid(mem_blk, nid, context);
790 
791 	ret = sysfs_create_link_nowarn(&node_devices[nid]->dev.kobj,
792 				       &mem_blk->dev.kobj,
793 				       kobject_name(&mem_blk->dev.kobj));
794 	if (ret && ret != -EEXIST)
795 		dev_err_ratelimited(&node_devices[nid]->dev,
796 				    "can't create link to %s in sysfs (%d)\n",
797 				    kobject_name(&mem_blk->dev.kobj), ret);
798 
799 	ret = sysfs_create_link_nowarn(&mem_blk->dev.kobj,
800 				&node_devices[nid]->dev.kobj,
801 				kobject_name(&node_devices[nid]->dev.kobj));
802 	if (ret && ret != -EEXIST)
803 		dev_err_ratelimited(&mem_blk->dev,
804 				    "can't create link to %s in sysfs (%d)\n",
805 				    kobject_name(&node_devices[nid]->dev.kobj),
806 				    ret);
807 }
808 
809 /*
810  * During hotplug we know that all pages in the memory block belong to the same
811  * node.
812  */
register_mem_block_under_node_hotplug(struct memory_block * mem_blk,void * arg)813 static int register_mem_block_under_node_hotplug(struct memory_block *mem_blk,
814 						 void *arg)
815 {
816 	int nid = *(int *)arg;
817 
818 	do_register_memory_block_under_node(nid, mem_blk, MEMINIT_HOTPLUG);
819 	return 0;
820 }
821 
822 /*
823  * Unregister a memory block device under the node it spans. Memory blocks
824  * with multiple nodes cannot be offlined and therefore also never be removed.
825  */
unregister_memory_block_under_nodes(struct memory_block * mem_blk)826 void unregister_memory_block_under_nodes(struct memory_block *mem_blk)
827 {
828 	if (mem_blk->nid == NUMA_NO_NODE)
829 		return;
830 
831 	sysfs_remove_link(&node_devices[mem_blk->nid]->dev.kobj,
832 			  kobject_name(&mem_blk->dev.kobj));
833 	sysfs_remove_link(&mem_blk->dev.kobj,
834 			  kobject_name(&node_devices[mem_blk->nid]->dev.kobj));
835 }
836 
837 /* register all memory blocks under the corresponding nodes */
register_memory_blocks_under_nodes(void)838 static void register_memory_blocks_under_nodes(void)
839 {
840 	struct memblock_region *r;
841 
842 	for_each_mem_region(r) {
843 		const unsigned long start_block_id = phys_to_block_id(r->base);
844 		const unsigned long end_block_id = phys_to_block_id(r->base + r->size - 1);
845 		const int nid = memblock_get_region_node(r);
846 		unsigned long block_id;
847 
848 		if (!node_online(nid))
849 			continue;
850 
851 		for (block_id = start_block_id; block_id <= end_block_id; block_id++) {
852 			struct memory_block *mem;
853 
854 			mem = find_memory_block_by_id(block_id);
855 			if (!mem)
856 				continue;
857 
858 			do_register_memory_block_under_node(nid, mem, MEMINIT_EARLY);
859 			put_device(&mem->dev);
860 		}
861 
862 	}
863 }
864 
register_memory_blocks_under_node_hotplug(int nid,unsigned long start_pfn,unsigned long end_pfn)865 void register_memory_blocks_under_node_hotplug(int nid, unsigned long start_pfn,
866 					       unsigned long end_pfn)
867 {
868 	walk_memory_blocks(PFN_PHYS(start_pfn), PFN_PHYS(end_pfn - start_pfn),
869 			   (void *)&nid, register_mem_block_under_node_hotplug);
870 	return;
871 }
872 #endif /* CONFIG_MEMORY_HOTPLUG */
873 
register_one_node(int nid)874 int register_one_node(int nid)
875 {
876 	int error;
877 	int cpu;
878 	struct node *node;
879 
880 	node = kzalloc(sizeof(struct node), GFP_KERNEL);
881 	if (!node)
882 		return -ENOMEM;
883 
884 	INIT_LIST_HEAD(&node->access_list);
885 	node_devices[nid] = node;
886 
887 	error = register_node(node_devices[nid], nid);
888 
889 	/* link cpu under this node */
890 	for_each_present_cpu(cpu) {
891 		if (cpu_to_node(cpu) == nid)
892 			register_cpu_under_node(cpu, nid);
893 	}
894 
895 	node_init_caches(nid);
896 
897 	return error;
898 }
899 
unregister_one_node(int nid)900 void unregister_one_node(int nid)
901 {
902 	if (!node_devices[nid])
903 		return;
904 
905 	unregister_node(node_devices[nid]);
906 	node_devices[nid] = NULL;
907 }
908 
909 /*
910  * node states attributes
911  */
912 
913 struct node_attr {
914 	struct device_attribute attr;
915 	enum node_states state;
916 };
917 
show_node_state(struct device * dev,struct device_attribute * attr,char * buf)918 static ssize_t show_node_state(struct device *dev,
919 			       struct device_attribute *attr, char *buf)
920 {
921 	struct node_attr *na = container_of(attr, struct node_attr, attr);
922 
923 	return sysfs_emit(buf, "%*pbl\n",
924 			  nodemask_pr_args(&node_states[na->state]));
925 }
926 
927 #define _NODE_ATTR(name, state) \
928 	{ __ATTR(name, 0444, show_node_state, NULL), state }
929 
930 static struct node_attr node_state_attr[] = {
931 	[N_POSSIBLE] = _NODE_ATTR(possible, N_POSSIBLE),
932 	[N_ONLINE] = _NODE_ATTR(online, N_ONLINE),
933 	[N_NORMAL_MEMORY] = _NODE_ATTR(has_normal_memory, N_NORMAL_MEMORY),
934 #ifdef CONFIG_HIGHMEM
935 	[N_HIGH_MEMORY] = _NODE_ATTR(has_high_memory, N_HIGH_MEMORY),
936 #endif
937 	[N_MEMORY] = _NODE_ATTR(has_memory, N_MEMORY),
938 	[N_CPU] = _NODE_ATTR(has_cpu, N_CPU),
939 	[N_GENERIC_INITIATOR] = _NODE_ATTR(has_generic_initiator,
940 					   N_GENERIC_INITIATOR),
941 };
942 
943 static struct attribute *node_state_attrs[] = {
944 	&node_state_attr[N_POSSIBLE].attr.attr,
945 	&node_state_attr[N_ONLINE].attr.attr,
946 	&node_state_attr[N_NORMAL_MEMORY].attr.attr,
947 #ifdef CONFIG_HIGHMEM
948 	&node_state_attr[N_HIGH_MEMORY].attr.attr,
949 #endif
950 	&node_state_attr[N_MEMORY].attr.attr,
951 	&node_state_attr[N_CPU].attr.attr,
952 	&node_state_attr[N_GENERIC_INITIATOR].attr.attr,
953 	NULL
954 };
955 
956 static const struct attribute_group memory_root_attr_group = {
957 	.attrs = node_state_attrs,
958 };
959 
960 static const struct attribute_group *cpu_root_attr_groups[] = {
961 	&memory_root_attr_group,
962 	NULL,
963 };
964 
node_dev_init(void)965 void __init node_dev_init(void)
966 {
967 	int ret, i;
968 
969  	BUILD_BUG_ON(ARRAY_SIZE(node_state_attr) != NR_NODE_STATES);
970  	BUILD_BUG_ON(ARRAY_SIZE(node_state_attrs)-1 != NR_NODE_STATES);
971 
972 	ret = subsys_system_register(&node_subsys, cpu_root_attr_groups);
973 	if (ret)
974 		panic("%s() failed to register subsystem: %d\n", __func__, ret);
975 
976 	/*
977 	 * Create all node devices, which will properly link the node
978 	 * to already created cpu devices.
979 	 */
980 	for_each_online_node(i) {
981 		ret =  register_one_node(i);
982 		if (ret)
983 			panic("%s() failed to add node: %d\n", __func__, ret);
984 	}
985 
986 	register_memory_blocks_under_nodes();
987 }
988