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13#include <linux/sysdev.h>
14#include <linux/module.h>
15#include <linux/init.h>
16#include <linux/topology.h>
17#include <linux/capability.h>
18#include <linux/device.h>
19#include <linux/memory.h>
20#include <linux/kobject.h>
21#include <linux/memory_hotplug.h>
22#include <linux/mm.h>
23#include <linux/mutex.h>
24#include <linux/stat.h>
25#include <linux/slab.h>
26
27#include <asm/atomic.h>
28#include <asm/uaccess.h>
29
30static DEFINE_MUTEX(mem_sysfs_mutex);
31
32#define MEMORY_CLASS_NAME "memory"
33
34static struct sysdev_class memory_sysdev_class = {
35 .name = MEMORY_CLASS_NAME,
36};
37
38static const char *memory_uevent_name(struct kset *kset, struct kobject *kobj)
39{
40 return MEMORY_CLASS_NAME;
41}
42
43static int memory_uevent(struct kset *kset, struct kobject *obj, struct kobj_uevent_env *env)
44{
45 int retval = 0;
46
47 return retval;
48}
49
50static const struct kset_uevent_ops memory_uevent_ops = {
51 .name = memory_uevent_name,
52 .uevent = memory_uevent,
53};
54
55static BLOCKING_NOTIFIER_HEAD(memory_chain);
56
57int register_memory_notifier(struct notifier_block *nb)
58{
59 return blocking_notifier_chain_register(&memory_chain, nb);
60}
61EXPORT_SYMBOL(register_memory_notifier);
62
63void unregister_memory_notifier(struct notifier_block *nb)
64{
65 blocking_notifier_chain_unregister(&memory_chain, nb);
66}
67EXPORT_SYMBOL(unregister_memory_notifier);
68
69static ATOMIC_NOTIFIER_HEAD(memory_isolate_chain);
70
71int register_memory_isolate_notifier(struct notifier_block *nb)
72{
73 return atomic_notifier_chain_register(&memory_isolate_chain, nb);
74}
75EXPORT_SYMBOL(register_memory_isolate_notifier);
76
77void unregister_memory_isolate_notifier(struct notifier_block *nb)
78{
79 atomic_notifier_chain_unregister(&memory_isolate_chain, nb);
80}
81EXPORT_SYMBOL(unregister_memory_isolate_notifier);
82
83
84
85
86static
87int register_memory(struct memory_block *memory, struct mem_section *section)
88{
89 int error;
90
91 memory->sysdev.cls = &memory_sysdev_class;
92 memory->sysdev.id = __section_nr(section);
93
94 error = sysdev_register(&memory->sysdev);
95 return error;
96}
97
98static void
99unregister_memory(struct memory_block *memory, struct mem_section *section)
100{
101 BUG_ON(memory->sysdev.cls != &memory_sysdev_class);
102 BUG_ON(memory->sysdev.id != __section_nr(section));
103
104
105 kobject_put(&memory->sysdev.kobj);
106 sysdev_unregister(&memory->sysdev);
107}
108
109
110
111
112
113
114static ssize_t show_mem_phys_index(struct sys_device *dev,
115 struct sysdev_attribute *attr, char *buf)
116{
117 struct memory_block *mem =
118 container_of(dev, struct memory_block, sysdev);
119 return sprintf(buf, "%08lx\n", mem->phys_index);
120}
121
122
123
124
125static ssize_t show_mem_removable(struct sys_device *dev,
126 struct sysdev_attribute *attr, char *buf)
127{
128 unsigned long start_pfn;
129 int ret;
130 struct memory_block *mem =
131 container_of(dev, struct memory_block, sysdev);
132
133 start_pfn = section_nr_to_pfn(mem->phys_index);
134 ret = is_mem_section_removable(start_pfn, PAGES_PER_SECTION);
135 return sprintf(buf, "%d\n", ret);
136}
137
138
139
140
141static ssize_t show_mem_state(struct sys_device *dev,
142 struct sysdev_attribute *attr, char *buf)
143{
144 struct memory_block *mem =
145 container_of(dev, struct memory_block, sysdev);
146 ssize_t len = 0;
147
148
149
150
151
152 switch (mem->state) {
153 case MEM_ONLINE:
154 len = sprintf(buf, "online\n");
155 break;
156 case MEM_OFFLINE:
157 len = sprintf(buf, "offline\n");
158 break;
159 case MEM_GOING_OFFLINE:
160 len = sprintf(buf, "going-offline\n");
161 break;
162 default:
163 len = sprintf(buf, "ERROR-UNKNOWN-%ld\n",
164 mem->state);
165 WARN_ON(1);
166 break;
167 }
168
169 return len;
170}
171
172int memory_notify(unsigned long val, void *v)
173{
174 return blocking_notifier_call_chain(&memory_chain, val, v);
175}
176
177int memory_isolate_notify(unsigned long val, void *v)
178{
179 return atomic_notifier_call_chain(&memory_isolate_chain, val, v);
180}
181
182
183
184
185
186static int
187memory_block_action(struct memory_block *mem, unsigned long action)
188{
189 int i;
190 unsigned long psection;
191 unsigned long start_pfn, start_paddr;
192 struct page *first_page;
193 int ret;
194 int old_state = mem->state;
195
196 psection = mem->phys_index;
197 first_page = pfn_to_page(psection << PFN_SECTION_SHIFT);
198
199
200
201
202
203
204 if (action == MEM_ONLINE) {
205 for (i = 0; i < PAGES_PER_SECTION; i++) {
206 if (PageReserved(first_page+i))
207 continue;
208
209 printk(KERN_WARNING "section number %ld page number %d "
210 "not reserved, was it already online? \n",
211 psection, i);
212 return -EBUSY;
213 }
214 }
215
216 switch (action) {
217 case MEM_ONLINE:
218 start_pfn = page_to_pfn(first_page);
219 ret = online_pages(start_pfn, PAGES_PER_SECTION);
220 break;
221 case MEM_OFFLINE:
222 mem->state = MEM_GOING_OFFLINE;
223 start_paddr = page_to_pfn(first_page) << PAGE_SHIFT;
224 ret = remove_memory(start_paddr,
225 PAGES_PER_SECTION << PAGE_SHIFT);
226 if (ret) {
227 mem->state = old_state;
228 break;
229 }
230 break;
231 default:
232 WARN(1, KERN_WARNING "%s(%p, %ld) unknown action: %ld\n",
233 __func__, mem, action, action);
234 ret = -EINVAL;
235 }
236
237 return ret;
238}
239
240static int memory_block_change_state(struct memory_block *mem,
241 unsigned long to_state, unsigned long from_state_req)
242{
243 int ret = 0;
244 mutex_lock(&mem->state_mutex);
245
246 if (mem->state != from_state_req) {
247 ret = -EINVAL;
248 goto out;
249 }
250
251 ret = memory_block_action(mem, to_state);
252 if (!ret)
253 mem->state = to_state;
254
255out:
256 mutex_unlock(&mem->state_mutex);
257 return ret;
258}
259
260static ssize_t
261store_mem_state(struct sys_device *dev,
262 struct sysdev_attribute *attr, const char *buf, size_t count)
263{
264 struct memory_block *mem;
265 unsigned int phys_section_nr;
266 int ret = -EINVAL;
267
268 mem = container_of(dev, struct memory_block, sysdev);
269 phys_section_nr = mem->phys_index;
270
271 if (!present_section_nr(phys_section_nr))
272 goto out;
273
274 if (!strncmp(buf, "online", min((int)count, 6)))
275 ret = memory_block_change_state(mem, MEM_ONLINE, MEM_OFFLINE);
276 else if(!strncmp(buf, "offline", min((int)count, 7)))
277 ret = memory_block_change_state(mem, MEM_OFFLINE, MEM_ONLINE);
278out:
279 if (ret)
280 return ret;
281 return count;
282}
283
284
285
286
287
288
289
290
291
292
293static ssize_t show_phys_device(struct sys_device *dev,
294 struct sysdev_attribute *attr, char *buf)
295{
296 struct memory_block *mem =
297 container_of(dev, struct memory_block, sysdev);
298 return sprintf(buf, "%d\n", mem->phys_device);
299}
300
301static SYSDEV_ATTR(phys_index, 0444, show_mem_phys_index, NULL);
302static SYSDEV_ATTR(state, 0644, show_mem_state, store_mem_state);
303static SYSDEV_ATTR(phys_device, 0444, show_phys_device, NULL);
304static SYSDEV_ATTR(removable, 0444, show_mem_removable, NULL);
305
306#define mem_create_simple_file(mem, attr_name) \
307 sysdev_create_file(&mem->sysdev, &attr_##attr_name)
308#define mem_remove_simple_file(mem, attr_name) \
309 sysdev_remove_file(&mem->sysdev, &attr_##attr_name)
310
311
312
313
314static ssize_t
315print_block_size(struct sysdev_class *class, struct sysdev_class_attribute *attr,
316 char *buf)
317{
318 return sprintf(buf, "%lx\n", (unsigned long)PAGES_PER_SECTION * PAGE_SIZE);
319}
320
321static SYSDEV_CLASS_ATTR(block_size_bytes, 0444, print_block_size, NULL);
322
323static int block_size_init(void)
324{
325 return sysfs_create_file(&memory_sysdev_class.kset.kobj,
326 &attr_block_size_bytes.attr);
327}
328
329
330
331
332
333
334
335#ifdef CONFIG_ARCH_MEMORY_PROBE
336static ssize_t
337memory_probe_store(struct class *class, struct class_attribute *attr,
338 const char *buf, size_t count)
339{
340 u64 phys_addr;
341 int nid;
342 int ret;
343
344 phys_addr = simple_strtoull(buf, NULL, 0);
345
346 nid = memory_add_physaddr_to_nid(phys_addr);
347 ret = add_memory(nid, phys_addr, PAGES_PER_SECTION << PAGE_SHIFT);
348
349 if (ret)
350 count = ret;
351
352 return count;
353}
354static CLASS_ATTR(probe, S_IWUSR, NULL, memory_probe_store);
355
356static int memory_probe_init(void)
357{
358 return sysfs_create_file(&memory_sysdev_class.kset.kobj,
359 &class_attr_probe.attr);
360}
361#else
362static inline int memory_probe_init(void)
363{
364 return 0;
365}
366#endif
367
368#ifdef CONFIG_MEMORY_FAILURE
369
370
371
372
373
374static ssize_t
375store_soft_offline_page(struct class *class,
376 struct class_attribute *attr,
377 const char *buf, size_t count)
378{
379 int ret;
380 u64 pfn;
381 if (!capable(CAP_SYS_ADMIN))
382 return -EPERM;
383 if (strict_strtoull(buf, 0, &pfn) < 0)
384 return -EINVAL;
385 pfn >>= PAGE_SHIFT;
386 if (!pfn_valid(pfn))
387 return -ENXIO;
388 ret = soft_offline_page(pfn_to_page(pfn), 0);
389 return ret == 0 ? count : ret;
390}
391
392
393static ssize_t
394store_hard_offline_page(struct class *class,
395 struct class_attribute *attr,
396 const char *buf, size_t count)
397{
398 int ret;
399 u64 pfn;
400 if (!capable(CAP_SYS_ADMIN))
401 return -EPERM;
402 if (strict_strtoull(buf, 0, &pfn) < 0)
403 return -EINVAL;
404 pfn >>= PAGE_SHIFT;
405 ret = __memory_failure(pfn, 0, 0);
406 return ret ? ret : count;
407}
408
409static CLASS_ATTR(soft_offline_page, 0644, NULL, store_soft_offline_page);
410static CLASS_ATTR(hard_offline_page, 0644, NULL, store_hard_offline_page);
411
412static __init int memory_fail_init(void)
413{
414 int err;
415
416 err = sysfs_create_file(&memory_sysdev_class.kset.kobj,
417 &class_attr_soft_offline_page.attr);
418 if (!err)
419 err = sysfs_create_file(&memory_sysdev_class.kset.kobj,
420 &class_attr_hard_offline_page.attr);
421 return err;
422}
423#else
424static inline int memory_fail_init(void)
425{
426 return 0;
427}
428#endif
429
430
431
432
433
434
435int __weak arch_get_memory_phys_device(unsigned long start_pfn)
436{
437 return 0;
438}
439
440struct memory_block *find_memory_block_hinted(struct mem_section *section,
441 struct memory_block *hint)
442{
443 struct kobject *kobj;
444 struct sys_device *sysdev;
445 struct memory_block *mem;
446 char name[sizeof(MEMORY_CLASS_NAME) + 9 + 1];
447
448 kobj = hint ? &hint->sysdev.kobj : NULL;
449
450
451
452
453
454 sprintf(&name[0], "%s%d", MEMORY_CLASS_NAME, __section_nr(section));
455
456 kobj = kset_find_obj_hinted(&memory_sysdev_class.kset, name, kobj);
457 if (!kobj)
458 return NULL;
459
460 sysdev = container_of(kobj, struct sys_device, kobj);
461 mem = container_of(sysdev, struct memory_block, sysdev);
462
463 return mem;
464}
465
466
467
468
469
470
471
472
473
474struct memory_block *find_memory_block(struct mem_section *section)
475{
476 return find_memory_block_hinted(section, NULL);
477}
478
479static int add_memory_block(int nid, struct mem_section *section,
480 unsigned long state, enum mem_add_context context)
481{
482 struct memory_block *mem = kzalloc(sizeof(*mem), GFP_KERNEL);
483 unsigned long start_pfn;
484 int ret = 0;
485
486 if (!mem)
487 return -ENOMEM;
488
489 mutex_lock(&mem_sysfs_mutex);
490
491 mem->phys_index = __section_nr(section);
492 mem->state = state;
493 mem->section_count++;
494 mutex_init(&mem->state_mutex);
495 start_pfn = section_nr_to_pfn(mem->phys_index);
496 mem->phys_device = arch_get_memory_phys_device(start_pfn);
497
498 ret = register_memory(mem, section);
499 if (!ret)
500 ret = mem_create_simple_file(mem, phys_index);
501 if (!ret)
502 ret = mem_create_simple_file(mem, state);
503 if (!ret)
504 ret = mem_create_simple_file(mem, phys_device);
505 if (!ret)
506 ret = mem_create_simple_file(mem, removable);
507 if (!ret) {
508 if (context == HOTPLUG)
509 ret = register_mem_sect_under_node(mem, nid);
510 }
511
512 mutex_unlock(&mem_sysfs_mutex);
513 return ret;
514}
515
516int remove_memory_block(unsigned long node_id, struct mem_section *section,
517 int phys_device)
518{
519 struct memory_block *mem;
520
521 mutex_lock(&mem_sysfs_mutex);
522 mem = find_memory_block(section);
523
524 mem->section_count--;
525 if (mem->section_count == 0) {
526 unregister_mem_sect_under_nodes(mem);
527 mem_remove_simple_file(mem, phys_index);
528 mem_remove_simple_file(mem, state);
529 mem_remove_simple_file(mem, phys_device);
530 mem_remove_simple_file(mem, removable);
531 unregister_memory(mem, section);
532 }
533
534 mutex_unlock(&mem_sysfs_mutex);
535 return 0;
536}
537
538
539
540
541
542int register_new_memory(int nid, struct mem_section *section)
543{
544 return add_memory_block(nid, section, MEM_OFFLINE, HOTPLUG);
545}
546
547int unregister_memory_section(struct mem_section *section)
548{
549 if (!present_section(section))
550 return -EINVAL;
551
552 return remove_memory_block(0, section, 0);
553}
554
555
556
557
558int __init memory_dev_init(void)
559{
560 unsigned int i;
561 int ret;
562 int err;
563
564 memory_sysdev_class.kset.uevent_ops = &memory_uevent_ops;
565 ret = sysdev_class_register(&memory_sysdev_class);
566 if (ret)
567 goto out;
568
569
570
571
572
573 for (i = 0; i < NR_MEM_SECTIONS; i++) {
574 if (!present_section_nr(i))
575 continue;
576 err = add_memory_block(0, __nr_to_section(i), MEM_ONLINE,
577 BOOT);
578 if (!ret)
579 ret = err;
580 }
581
582 err = memory_probe_init();
583 if (!ret)
584 ret = err;
585 err = memory_fail_init();
586 if (!ret)
587 ret = err;
588 err = block_size_init();
589 if (!ret)
590 ret = err;
591out:
592 if (ret)
593 printk(KERN_ERR "%s() failed: %d\n", __func__, ret);
594 return ret;
595}
596