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