xref: /linux/mm/damon/sysfs.c (revision f4e98954234b104c23902ee5bb4e59be6f9904a7)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * DAMON sysfs Interface
4  *
5  * Copyright (c) 2022 SeongJae Park <sj@kernel.org>
6  */
7 
8 #include <linux/pid.h>
9 #include <linux/sched.h>
10 #include <linux/slab.h>
11 
12 #include "sysfs-common.h"
13 
14 /*
15  * init region directory
16  */
17 
18 struct damon_sysfs_region {
19 	struct kobject kobj;
20 	struct damon_addr_range ar;
21 };
22 
23 static struct damon_sysfs_region *damon_sysfs_region_alloc(void)
24 {
25 	return kzalloc_obj(struct damon_sysfs_region);
26 }
27 
28 static ssize_t start_show(struct kobject *kobj, struct kobj_attribute *attr,
29 		char *buf)
30 {
31 	struct damon_sysfs_region *region = container_of(kobj,
32 			struct damon_sysfs_region, kobj);
33 
34 	return sysfs_emit(buf, "%lu\n", region->ar.start);
35 }
36 
37 static ssize_t start_store(struct kobject *kobj, struct kobj_attribute *attr,
38 		const char *buf, size_t count)
39 {
40 	struct damon_sysfs_region *region = container_of(kobj,
41 			struct damon_sysfs_region, kobj);
42 	int err = kstrtoul(buf, 0, &region->ar.start);
43 
44 	return err ? err : count;
45 }
46 
47 static ssize_t end_show(struct kobject *kobj, struct kobj_attribute *attr,
48 		char *buf)
49 {
50 	struct damon_sysfs_region *region = container_of(kobj,
51 			struct damon_sysfs_region, kobj);
52 
53 	return sysfs_emit(buf, "%lu\n", region->ar.end);
54 }
55 
56 static ssize_t end_store(struct kobject *kobj, struct kobj_attribute *attr,
57 		const char *buf, size_t count)
58 {
59 	struct damon_sysfs_region *region = container_of(kobj,
60 			struct damon_sysfs_region, kobj);
61 	int err = kstrtoul(buf, 0, &region->ar.end);
62 
63 	return err ? err : count;
64 }
65 
66 static void damon_sysfs_region_release(struct kobject *kobj)
67 {
68 	kfree(container_of(kobj, struct damon_sysfs_region, kobj));
69 }
70 
71 static struct kobj_attribute damon_sysfs_region_start_attr =
72 		__ATTR_RW_MODE(start, 0600);
73 
74 static struct kobj_attribute damon_sysfs_region_end_attr =
75 		__ATTR_RW_MODE(end, 0600);
76 
77 static struct attribute *damon_sysfs_region_attrs[] = {
78 	&damon_sysfs_region_start_attr.attr,
79 	&damon_sysfs_region_end_attr.attr,
80 	NULL,
81 };
82 ATTRIBUTE_GROUPS(damon_sysfs_region);
83 
84 static const struct kobj_type damon_sysfs_region_ktype = {
85 	.release = damon_sysfs_region_release,
86 	.sysfs_ops = &kobj_sysfs_ops,
87 	.default_groups = damon_sysfs_region_groups,
88 };
89 
90 /*
91  * init_regions directory
92  */
93 
94 struct damon_sysfs_regions {
95 	struct kobject kobj;
96 	struct damon_sysfs_region **regions_arr;
97 	int nr;
98 };
99 
100 static struct damon_sysfs_regions *damon_sysfs_regions_alloc(void)
101 {
102 	return kzalloc_obj(struct damon_sysfs_regions);
103 }
104 
105 static void damon_sysfs_regions_rm_dirs(struct damon_sysfs_regions *regions)
106 {
107 	struct damon_sysfs_region **regions_arr = regions->regions_arr;
108 	int i;
109 
110 	for (i = 0; i < regions->nr; i++)
111 		kobject_put(&regions_arr[i]->kobj);
112 	regions->nr = 0;
113 	kfree(regions_arr);
114 	regions->regions_arr = NULL;
115 }
116 
117 static int damon_sysfs_regions_add_dirs(struct damon_sysfs_regions *regions,
118 		int nr_regions)
119 {
120 	struct damon_sysfs_region **regions_arr, *region;
121 	int err, i;
122 
123 	damon_sysfs_regions_rm_dirs(regions);
124 	if (!nr_regions)
125 		return 0;
126 
127 	regions_arr = kmalloc_objs(*regions_arr, nr_regions,
128 				   GFP_KERNEL | __GFP_NOWARN);
129 	if (!regions_arr)
130 		return -ENOMEM;
131 	regions->regions_arr = regions_arr;
132 
133 	for (i = 0; i < nr_regions; i++) {
134 		region = damon_sysfs_region_alloc();
135 		if (!region) {
136 			damon_sysfs_regions_rm_dirs(regions);
137 			return -ENOMEM;
138 		}
139 
140 		err = kobject_init_and_add(&region->kobj,
141 				&damon_sysfs_region_ktype, &regions->kobj,
142 				"%d", i);
143 		if (err) {
144 			kobject_put(&region->kobj);
145 			damon_sysfs_regions_rm_dirs(regions);
146 			return err;
147 		}
148 
149 		regions_arr[i] = region;
150 		regions->nr++;
151 	}
152 	return 0;
153 }
154 
155 static ssize_t nr_regions_show(struct kobject *kobj,
156 		struct kobj_attribute *attr, char *buf)
157 {
158 	struct damon_sysfs_regions *regions = container_of(kobj,
159 			struct damon_sysfs_regions, kobj);
160 
161 	return sysfs_emit(buf, "%d\n", regions->nr);
162 }
163 
164 static ssize_t nr_regions_store(struct kobject *kobj,
165 		struct kobj_attribute *attr, const char *buf, size_t count)
166 {
167 	struct damon_sysfs_regions *regions;
168 	int nr, err = kstrtoint(buf, 0, &nr);
169 
170 	if (err)
171 		return err;
172 	if (nr < 0)
173 		return -EINVAL;
174 
175 	regions = container_of(kobj, struct damon_sysfs_regions, kobj);
176 
177 	if (!mutex_trylock(&damon_sysfs_lock))
178 		return -EBUSY;
179 	err = damon_sysfs_regions_add_dirs(regions, nr);
180 	mutex_unlock(&damon_sysfs_lock);
181 	if (err)
182 		return err;
183 
184 	return count;
185 }
186 
187 static void damon_sysfs_regions_release(struct kobject *kobj)
188 {
189 	kfree(container_of(kobj, struct damon_sysfs_regions, kobj));
190 }
191 
192 static struct kobj_attribute damon_sysfs_regions_nr_attr =
193 		__ATTR_RW_MODE(nr_regions, 0600);
194 
195 static struct attribute *damon_sysfs_regions_attrs[] = {
196 	&damon_sysfs_regions_nr_attr.attr,
197 	NULL,
198 };
199 ATTRIBUTE_GROUPS(damon_sysfs_regions);
200 
201 static const struct kobj_type damon_sysfs_regions_ktype = {
202 	.release = damon_sysfs_regions_release,
203 	.sysfs_ops = &kobj_sysfs_ops,
204 	.default_groups = damon_sysfs_regions_groups,
205 };
206 
207 /*
208  * target directory
209  */
210 
211 struct damon_sysfs_target {
212 	struct kobject kobj;
213 	struct damon_sysfs_regions *regions;
214 	int pid;
215 	bool obsolete;
216 };
217 
218 static struct damon_sysfs_target *damon_sysfs_target_alloc(void)
219 {
220 	return kzalloc_obj(struct damon_sysfs_target);
221 }
222 
223 static int damon_sysfs_target_add_dirs(struct damon_sysfs_target *target)
224 {
225 	struct damon_sysfs_regions *regions = damon_sysfs_regions_alloc();
226 	int err;
227 
228 	if (!regions)
229 		return -ENOMEM;
230 
231 	err = kobject_init_and_add(&regions->kobj, &damon_sysfs_regions_ktype,
232 			&target->kobj, "regions");
233 	if (err)
234 		kobject_put(&regions->kobj);
235 	else
236 		target->regions = regions;
237 	return err;
238 }
239 
240 static void damon_sysfs_target_rm_dirs(struct damon_sysfs_target *target)
241 {
242 	damon_sysfs_regions_rm_dirs(target->regions);
243 	kobject_put(&target->regions->kobj);
244 }
245 
246 static ssize_t pid_target_show(struct kobject *kobj,
247 		struct kobj_attribute *attr, char *buf)
248 {
249 	struct damon_sysfs_target *target = container_of(kobj,
250 			struct damon_sysfs_target, kobj);
251 
252 	return sysfs_emit(buf, "%d\n", target->pid);
253 }
254 
255 static ssize_t pid_target_store(struct kobject *kobj,
256 		struct kobj_attribute *attr, const char *buf, size_t count)
257 {
258 	struct damon_sysfs_target *target = container_of(kobj,
259 			struct damon_sysfs_target, kobj);
260 	int err = kstrtoint(buf, 0, &target->pid);
261 
262 	if (err)
263 		return -EINVAL;
264 	return count;
265 }
266 
267 static ssize_t obsolete_target_show(struct kobject *kobj,
268 		struct kobj_attribute *attr, char *buf)
269 {
270 	struct damon_sysfs_target *target = container_of(kobj,
271 			struct damon_sysfs_target, kobj);
272 
273 	return sysfs_emit(buf, "%c\n", target->obsolete ? 'Y' : 'N');
274 }
275 
276 static ssize_t obsolete_target_store(struct kobject *kobj,
277 		struct kobj_attribute *attr, const char *buf, size_t count)
278 {
279 	struct damon_sysfs_target *target = container_of(kobj,
280 			struct damon_sysfs_target, kobj);
281 	bool obsolete;
282 	int err = kstrtobool(buf, &obsolete);
283 
284 	if (err)
285 		return err;
286 	target->obsolete = obsolete;
287 	return count;
288 }
289 
290 static void damon_sysfs_target_release(struct kobject *kobj)
291 {
292 	kfree(container_of(kobj, struct damon_sysfs_target, kobj));
293 }
294 
295 static struct kobj_attribute damon_sysfs_target_pid_attr =
296 		__ATTR_RW_MODE(pid_target, 0600);
297 
298 static struct kobj_attribute damon_sysfs_target_obsolete_attr =
299 		__ATTR_RW_MODE(obsolete_target, 0600);
300 
301 static struct attribute *damon_sysfs_target_attrs[] = {
302 	&damon_sysfs_target_pid_attr.attr,
303 	&damon_sysfs_target_obsolete_attr.attr,
304 	NULL,
305 };
306 ATTRIBUTE_GROUPS(damon_sysfs_target);
307 
308 static const struct kobj_type damon_sysfs_target_ktype = {
309 	.release = damon_sysfs_target_release,
310 	.sysfs_ops = &kobj_sysfs_ops,
311 	.default_groups = damon_sysfs_target_groups,
312 };
313 
314 /*
315  * targets directory
316  */
317 
318 struct damon_sysfs_targets {
319 	struct kobject kobj;
320 	struct damon_sysfs_target **targets_arr;
321 	int nr;
322 };
323 
324 static struct damon_sysfs_targets *damon_sysfs_targets_alloc(void)
325 {
326 	return kzalloc_obj(struct damon_sysfs_targets);
327 }
328 
329 static void damon_sysfs_targets_rm_dirs(struct damon_sysfs_targets *targets)
330 {
331 	struct damon_sysfs_target **targets_arr = targets->targets_arr;
332 	int i;
333 
334 	for (i = 0; i < targets->nr; i++) {
335 		damon_sysfs_target_rm_dirs(targets_arr[i]);
336 		kobject_put(&targets_arr[i]->kobj);
337 	}
338 	targets->nr = 0;
339 	kfree(targets_arr);
340 	targets->targets_arr = NULL;
341 }
342 
343 static int damon_sysfs_targets_add_dirs(struct damon_sysfs_targets *targets,
344 		int nr_targets)
345 {
346 	struct damon_sysfs_target **targets_arr, *target;
347 	int err, i;
348 
349 	damon_sysfs_targets_rm_dirs(targets);
350 	if (!nr_targets)
351 		return 0;
352 
353 	targets_arr = kmalloc_objs(*targets_arr, nr_targets,
354 				   GFP_KERNEL | __GFP_NOWARN);
355 	if (!targets_arr)
356 		return -ENOMEM;
357 	targets->targets_arr = targets_arr;
358 
359 	for (i = 0; i < nr_targets; i++) {
360 		target = damon_sysfs_target_alloc();
361 		if (!target) {
362 			damon_sysfs_targets_rm_dirs(targets);
363 			return -ENOMEM;
364 		}
365 
366 		err = kobject_init_and_add(&target->kobj,
367 				&damon_sysfs_target_ktype, &targets->kobj,
368 				"%d", i);
369 		if (err)
370 			goto out;
371 
372 		err = damon_sysfs_target_add_dirs(target);
373 		if (err)
374 			goto out;
375 
376 		targets_arr[i] = target;
377 		targets->nr++;
378 	}
379 	return 0;
380 
381 out:
382 	damon_sysfs_targets_rm_dirs(targets);
383 	kobject_put(&target->kobj);
384 	return err;
385 }
386 
387 static ssize_t nr_targets_show(struct kobject *kobj,
388 		struct kobj_attribute *attr, char *buf)
389 {
390 	struct damon_sysfs_targets *targets = container_of(kobj,
391 			struct damon_sysfs_targets, kobj);
392 
393 	return sysfs_emit(buf, "%d\n", targets->nr);
394 }
395 
396 static ssize_t nr_targets_store(struct kobject *kobj,
397 		struct kobj_attribute *attr, const char *buf, size_t count)
398 {
399 	struct damon_sysfs_targets *targets;
400 	int nr, err = kstrtoint(buf, 0, &nr);
401 
402 	if (err)
403 		return err;
404 	if (nr < 0)
405 		return -EINVAL;
406 
407 	targets = container_of(kobj, struct damon_sysfs_targets, kobj);
408 
409 	if (!mutex_trylock(&damon_sysfs_lock))
410 		return -EBUSY;
411 	err = damon_sysfs_targets_add_dirs(targets, nr);
412 	mutex_unlock(&damon_sysfs_lock);
413 	if (err)
414 		return err;
415 
416 	return count;
417 }
418 
419 static void damon_sysfs_targets_release(struct kobject *kobj)
420 {
421 	kfree(container_of(kobj, struct damon_sysfs_targets, kobj));
422 }
423 
424 static struct kobj_attribute damon_sysfs_targets_nr_attr =
425 		__ATTR_RW_MODE(nr_targets, 0600);
426 
427 static struct attribute *damon_sysfs_targets_attrs[] = {
428 	&damon_sysfs_targets_nr_attr.attr,
429 	NULL,
430 };
431 ATTRIBUTE_GROUPS(damon_sysfs_targets);
432 
433 static const struct kobj_type damon_sysfs_targets_ktype = {
434 	.release = damon_sysfs_targets_release,
435 	.sysfs_ops = &kobj_sysfs_ops,
436 	.default_groups = damon_sysfs_targets_groups,
437 };
438 
439 /*
440  * intervals goal directory
441  */
442 
443 struct damon_sysfs_intervals_goal {
444 	struct kobject kobj;
445 	unsigned long access_bp;
446 	unsigned long aggrs;
447 	unsigned long min_sample_us;
448 	unsigned long max_sample_us;
449 };
450 
451 static struct damon_sysfs_intervals_goal *damon_sysfs_intervals_goal_alloc(
452 		unsigned long access_bp, unsigned long aggrs,
453 		unsigned long min_sample_us, unsigned long max_sample_us)
454 {
455 	struct damon_sysfs_intervals_goal *goal = kmalloc_obj(*goal);
456 
457 	if (!goal)
458 		return NULL;
459 
460 	goal->kobj = (struct kobject){};
461 	goal->access_bp = access_bp;
462 	goal->aggrs = aggrs;
463 	goal->min_sample_us = min_sample_us;
464 	goal->max_sample_us = max_sample_us;
465 	return goal;
466 }
467 
468 static ssize_t access_bp_show(struct kobject *kobj,
469 		struct kobj_attribute *attr, char *buf)
470 {
471 	struct damon_sysfs_intervals_goal *goal = container_of(kobj,
472 			struct damon_sysfs_intervals_goal, kobj);
473 
474 	return sysfs_emit(buf, "%lu\n", goal->access_bp);
475 }
476 
477 static ssize_t access_bp_store(struct kobject *kobj,
478 		struct kobj_attribute *attr, const char *buf, size_t count)
479 {
480 	struct damon_sysfs_intervals_goal *goal = container_of(kobj,
481 			struct damon_sysfs_intervals_goal, kobj);
482 	unsigned long nr;
483 	int err = kstrtoul(buf, 0, &nr);
484 
485 	if (err)
486 		return err;
487 
488 	goal->access_bp = nr;
489 	return count;
490 }
491 
492 static ssize_t aggrs_show(struct kobject *kobj,
493 		struct kobj_attribute *attr, char *buf)
494 {
495 	struct damon_sysfs_intervals_goal *goal = container_of(kobj,
496 			struct damon_sysfs_intervals_goal, kobj);
497 
498 	return sysfs_emit(buf, "%lu\n", goal->aggrs);
499 }
500 
501 static ssize_t aggrs_store(struct kobject *kobj,
502 		struct kobj_attribute *attr, const char *buf, size_t count)
503 {
504 	struct damon_sysfs_intervals_goal *goal = container_of(kobj,
505 			struct damon_sysfs_intervals_goal, kobj);
506 	unsigned long nr;
507 	int err = kstrtoul(buf, 0, &nr);
508 
509 	if (err)
510 		return err;
511 
512 	goal->aggrs = nr;
513 	return count;
514 }
515 
516 static ssize_t min_sample_us_show(struct kobject *kobj,
517 		struct kobj_attribute *attr, char *buf)
518 {
519 	struct damon_sysfs_intervals_goal *goal = container_of(kobj,
520 			struct damon_sysfs_intervals_goal, kobj);
521 
522 	return sysfs_emit(buf, "%lu\n", goal->min_sample_us);
523 }
524 
525 static ssize_t min_sample_us_store(struct kobject *kobj,
526 		struct kobj_attribute *attr, const char *buf, size_t count)
527 {
528 	struct damon_sysfs_intervals_goal *goal = container_of(kobj,
529 			struct damon_sysfs_intervals_goal, kobj);
530 	unsigned long nr;
531 	int err = kstrtoul(buf, 0, &nr);
532 
533 	if (err)
534 		return err;
535 
536 	goal->min_sample_us = nr;
537 	return count;
538 }
539 
540 static ssize_t max_sample_us_show(struct kobject *kobj,
541 		struct kobj_attribute *attr, char *buf)
542 {
543 	struct damon_sysfs_intervals_goal *goal = container_of(kobj,
544 			struct damon_sysfs_intervals_goal, kobj);
545 
546 	return sysfs_emit(buf, "%lu\n", goal->max_sample_us);
547 }
548 
549 static ssize_t max_sample_us_store(struct kobject *kobj,
550 		struct kobj_attribute *attr, const char *buf, size_t count)
551 {
552 	struct damon_sysfs_intervals_goal *goal = container_of(kobj,
553 			struct damon_sysfs_intervals_goal, kobj);
554 	unsigned long nr;
555 	int err = kstrtoul(buf, 0, &nr);
556 
557 	if (err)
558 		return err;
559 
560 	goal->max_sample_us = nr;
561 	return count;
562 }
563 
564 static void damon_sysfs_intervals_goal_release(struct kobject *kobj)
565 {
566 	kfree(container_of(kobj, struct damon_sysfs_intervals_goal, kobj));
567 }
568 
569 static struct kobj_attribute damon_sysfs_intervals_goal_access_bp_attr =
570 		__ATTR_RW_MODE(access_bp, 0600);
571 
572 static struct kobj_attribute damon_sysfs_intervals_goal_aggrs_attr =
573 		__ATTR_RW_MODE(aggrs, 0600);
574 
575 static struct kobj_attribute damon_sysfs_intervals_goal_min_sample_us_attr =
576 		__ATTR_RW_MODE(min_sample_us, 0600);
577 
578 static struct kobj_attribute damon_sysfs_intervals_goal_max_sample_us_attr =
579 		__ATTR_RW_MODE(max_sample_us, 0600);
580 
581 static struct attribute *damon_sysfs_intervals_goal_attrs[] = {
582 	&damon_sysfs_intervals_goal_access_bp_attr.attr,
583 	&damon_sysfs_intervals_goal_aggrs_attr.attr,
584 	&damon_sysfs_intervals_goal_min_sample_us_attr.attr,
585 	&damon_sysfs_intervals_goal_max_sample_us_attr.attr,
586 	NULL,
587 };
588 ATTRIBUTE_GROUPS(damon_sysfs_intervals_goal);
589 
590 static const struct kobj_type damon_sysfs_intervals_goal_ktype = {
591 	.release = damon_sysfs_intervals_goal_release,
592 	.sysfs_ops = &kobj_sysfs_ops,
593 	.default_groups = damon_sysfs_intervals_goal_groups,
594 };
595 
596 /*
597  * intervals directory
598  */
599 
600 struct damon_sysfs_intervals {
601 	struct kobject kobj;
602 	unsigned long sample_us;
603 	unsigned long aggr_us;
604 	unsigned long update_us;
605 	struct damon_sysfs_intervals_goal *intervals_goal;
606 };
607 
608 static struct damon_sysfs_intervals *damon_sysfs_intervals_alloc(
609 		unsigned long sample_us, unsigned long aggr_us,
610 		unsigned long update_us)
611 {
612 	struct damon_sysfs_intervals *intervals = kmalloc_obj(*intervals);
613 
614 	if (!intervals)
615 		return NULL;
616 
617 	intervals->kobj = (struct kobject){};
618 	intervals->sample_us = sample_us;
619 	intervals->aggr_us = aggr_us;
620 	intervals->update_us = update_us;
621 	return intervals;
622 }
623 
624 static int damon_sysfs_intervals_add_dirs(struct damon_sysfs_intervals *intervals)
625 {
626 	struct damon_sysfs_intervals_goal *goal;
627 	int err;
628 
629 	goal = damon_sysfs_intervals_goal_alloc(0, 0, 0, 0);
630 	if (!goal)
631 		return -ENOMEM;
632 
633 	err = kobject_init_and_add(&goal->kobj,
634 			&damon_sysfs_intervals_goal_ktype, &intervals->kobj,
635 			"intervals_goal");
636 	if (err) {
637 		kobject_put(&goal->kobj);
638 		intervals->intervals_goal = NULL;
639 		return err;
640 	}
641 	intervals->intervals_goal = goal;
642 	return 0;
643 }
644 
645 static void damon_sysfs_intervals_rm_dirs(struct damon_sysfs_intervals *intervals)
646 {
647 	kobject_put(&intervals->intervals_goal->kobj);
648 }
649 
650 static ssize_t sample_us_show(struct kobject *kobj,
651 		struct kobj_attribute *attr, char *buf)
652 {
653 	struct damon_sysfs_intervals *intervals = container_of(kobj,
654 			struct damon_sysfs_intervals, kobj);
655 
656 	return sysfs_emit(buf, "%lu\n", intervals->sample_us);
657 }
658 
659 static ssize_t sample_us_store(struct kobject *kobj,
660 		struct kobj_attribute *attr, const char *buf, size_t count)
661 {
662 	struct damon_sysfs_intervals *intervals = container_of(kobj,
663 			struct damon_sysfs_intervals, kobj);
664 	unsigned long us;
665 	int err = kstrtoul(buf, 0, &us);
666 
667 	if (err)
668 		return err;
669 
670 	intervals->sample_us = us;
671 	return count;
672 }
673 
674 static ssize_t aggr_us_show(struct kobject *kobj, struct kobj_attribute *attr,
675 		char *buf)
676 {
677 	struct damon_sysfs_intervals *intervals = container_of(kobj,
678 			struct damon_sysfs_intervals, kobj);
679 
680 	return sysfs_emit(buf, "%lu\n", intervals->aggr_us);
681 }
682 
683 static ssize_t aggr_us_store(struct kobject *kobj, struct kobj_attribute *attr,
684 		const char *buf, size_t count)
685 {
686 	struct damon_sysfs_intervals *intervals = container_of(kobj,
687 			struct damon_sysfs_intervals, kobj);
688 	unsigned long us;
689 	int err = kstrtoul(buf, 0, &us);
690 
691 	if (err)
692 		return err;
693 
694 	intervals->aggr_us = us;
695 	return count;
696 }
697 
698 static ssize_t update_us_show(struct kobject *kobj,
699 		struct kobj_attribute *attr, char *buf)
700 {
701 	struct damon_sysfs_intervals *intervals = container_of(kobj,
702 			struct damon_sysfs_intervals, kobj);
703 
704 	return sysfs_emit(buf, "%lu\n", intervals->update_us);
705 }
706 
707 static ssize_t update_us_store(struct kobject *kobj,
708 		struct kobj_attribute *attr, const char *buf, size_t count)
709 {
710 	struct damon_sysfs_intervals *intervals = container_of(kobj,
711 			struct damon_sysfs_intervals, kobj);
712 	unsigned long us;
713 	int err = kstrtoul(buf, 0, &us);
714 
715 	if (err)
716 		return err;
717 
718 	intervals->update_us = us;
719 	return count;
720 }
721 
722 static void damon_sysfs_intervals_release(struct kobject *kobj)
723 {
724 	kfree(container_of(kobj, struct damon_sysfs_intervals, kobj));
725 }
726 
727 static struct kobj_attribute damon_sysfs_intervals_sample_us_attr =
728 		__ATTR_RW_MODE(sample_us, 0600);
729 
730 static struct kobj_attribute damon_sysfs_intervals_aggr_us_attr =
731 		__ATTR_RW_MODE(aggr_us, 0600);
732 
733 static struct kobj_attribute damon_sysfs_intervals_update_us_attr =
734 		__ATTR_RW_MODE(update_us, 0600);
735 
736 static struct attribute *damon_sysfs_intervals_attrs[] = {
737 	&damon_sysfs_intervals_sample_us_attr.attr,
738 	&damon_sysfs_intervals_aggr_us_attr.attr,
739 	&damon_sysfs_intervals_update_us_attr.attr,
740 	NULL,
741 };
742 ATTRIBUTE_GROUPS(damon_sysfs_intervals);
743 
744 static const struct kobj_type damon_sysfs_intervals_ktype = {
745 	.release = damon_sysfs_intervals_release,
746 	.sysfs_ops = &kobj_sysfs_ops,
747 	.default_groups = damon_sysfs_intervals_groups,
748 };
749 
750 /*
751  * filter directory
752  */
753 
754 struct damon_sysfs_filter {
755 	struct kobject kobj;
756 	enum damon_filter_type type;
757 	bool matching;
758 	bool allow;
759 };
760 
761 static struct damon_sysfs_filter *damon_sysfs_filter_alloc(void)
762 {
763 	return kzalloc_obj(struct damon_sysfs_filter);
764 }
765 
766 struct damon_sysfs_filter_type_name {
767 	enum damon_filter_type type;
768 	char *name;
769 };
770 
771 static const struct damon_sysfs_filter_type_name
772 damon_sysfs_filter_type_names[] = {
773 	{
774 		.type = DAMON_FILTER_TYPE_ANON,
775 		.name = "anon",
776 	},
777 };
778 
779 static ssize_t type_show(struct kobject *kobj,
780 		struct kobj_attribute *attr, char *buf)
781 {
782 	struct damon_sysfs_filter *filter = container_of(kobj,
783 			struct damon_sysfs_filter, kobj);
784 	int i;
785 
786 	for (i = 0; i < ARRAY_SIZE(damon_sysfs_filter_type_names); i++) {
787 		const struct damon_sysfs_filter_type_name *type_name;
788 
789 		type_name = &damon_sysfs_filter_type_names[i];
790 		if (type_name->type == filter->type)
791 			return sysfs_emit(buf, "%s\n", type_name->name);
792 	}
793 	return -EINVAL;
794 }
795 
796 static ssize_t type_store(struct kobject *kobj,
797 		struct kobj_attribute *attr, const char *buf, size_t count)
798 {
799 	struct damon_sysfs_filter *filter = container_of(kobj,
800 			struct damon_sysfs_filter, kobj);
801 	ssize_t ret = -EINVAL;
802 	int i;
803 
804 	for (i = 0; i < ARRAY_SIZE(damon_sysfs_filter_type_names); i++) {
805 		const struct damon_sysfs_filter_type_name *type_name;
806 
807 		type_name = &damon_sysfs_filter_type_names[i];
808 		if (sysfs_streq(buf, type_name->name)) {
809 			filter->type = type_name->type;
810 			ret = count;
811 			break;
812 		}
813 	}
814 	return ret;
815 }
816 
817 static ssize_t matching_show(struct kobject *kobj,
818 		struct kobj_attribute *attr, char *buf)
819 {
820 	struct damon_sysfs_filter *filter = container_of(kobj,
821 			struct damon_sysfs_filter, kobj);
822 
823 	return sysfs_emit(buf, "%c\n", filter->matching ? 'Y' : 'N');
824 }
825 
826 static ssize_t matching_store(struct kobject *kobj,
827 		struct kobj_attribute *attr, const char *buf, size_t count)
828 {
829 	struct damon_sysfs_filter *filter = container_of(kobj,
830 			struct damon_sysfs_filter, kobj);
831 	bool matching;
832 	int err = kstrtobool(buf, &matching);
833 
834 	if (err)
835 		return err;
836 
837 	filter->matching = matching;
838 	return count;
839 }
840 
841 static ssize_t allow_show(struct kobject *kobj,
842 		struct kobj_attribute *attr, char *buf)
843 {
844 	struct damon_sysfs_filter *filter = container_of(kobj,
845 			struct damon_sysfs_filter, kobj);
846 
847 	return sysfs_emit(buf, "%c\n", filter->allow ? 'Y' : 'N');
848 }
849 
850 static ssize_t allow_store(struct kobject *kobj,
851 		struct kobj_attribute *attr, const char *buf, size_t count)
852 {
853 	struct damon_sysfs_filter *filter = container_of(kobj,
854 			struct damon_sysfs_filter, kobj);
855 	bool allow;
856 	int err = kstrtobool(buf, &allow);
857 
858 	if (err)
859 		return err;
860 
861 	filter->allow = allow;
862 	return count;
863 }
864 
865 static void damon_sysfs_filter_release(struct kobject *kobj)
866 {
867 	struct damon_sysfs_filter *filter = container_of(kobj,
868 			struct damon_sysfs_filter, kobj);
869 
870 	kfree(filter);
871 }
872 
873 static struct kobj_attribute damon_sysfs_filter_type_attr =
874 		__ATTR_RW_MODE(type, 0600);
875 
876 static struct kobj_attribute damon_sysfs_filter_matching_attr =
877 		__ATTR_RW_MODE(matching, 0600);
878 
879 static struct kobj_attribute damon_sysfs_filter_allow_attr =
880 		__ATTR_RW_MODE(allow, 0600);
881 
882 static struct attribute *damon_sysfs_filter_attrs[] = {
883 	&damon_sysfs_filter_type_attr.attr,
884 	&damon_sysfs_filter_matching_attr.attr,
885 	&damon_sysfs_filter_allow_attr.attr,
886 	NULL,
887 };
888 ATTRIBUTE_GROUPS(damon_sysfs_filter);
889 
890 static const struct kobj_type damon_sysfs_filter_ktype = {
891 	.release = damon_sysfs_filter_release,
892 	.sysfs_ops = &kobj_sysfs_ops,
893 	.default_groups = damon_sysfs_filter_groups,
894 };
895 
896 /*
897  * filters directory
898  */
899 
900 struct damon_sysfs_filters {
901 	struct kobject kobj;
902 	struct damon_sysfs_filter **filters_arr;
903 	int nr;
904 };
905 
906 static struct damon_sysfs_filters *damon_sysfs_filters_alloc(void)
907 {
908 	return kzalloc_obj(struct damon_sysfs_filters);
909 }
910 
911 static void damon_sysfs_filters_rm_dirs(struct damon_sysfs_filters *filters)
912 {
913 	struct damon_sysfs_filter **filters_arr = filters->filters_arr;
914 	int i;
915 
916 	for (i = 0; i < filters->nr; i++)
917 		kobject_put(&filters_arr[i]->kobj);
918 	filters->nr = 0;
919 	kfree(filters_arr);
920 	filters->filters_arr = NULL;
921 }
922 
923 static int damon_sysfs_filters_add_dirs(
924 		struct damon_sysfs_filters *filters, int nr_filters)
925 {
926 	struct damon_sysfs_filter **filters_arr, *filter;
927 	int err, i;
928 
929 	damon_sysfs_filters_rm_dirs(filters);
930 	if (!nr_filters)
931 		return 0;
932 
933 	filters_arr = kmalloc_objs(*filters_arr, nr_filters,
934 				   GFP_KERNEL | __GFP_NOWARN);
935 	if (!filters_arr)
936 		return -ENOMEM;
937 	filters->filters_arr = filters_arr;
938 
939 	for (i = 0; i < nr_filters; i++) {
940 		filter = damon_sysfs_filter_alloc();
941 		if (!filter) {
942 			damon_sysfs_filters_rm_dirs(filters);
943 			return -ENOMEM;
944 		}
945 
946 		err = kobject_init_and_add(&filter->kobj,
947 				&damon_sysfs_filter_ktype, &filters->kobj,
948 				"%d", i);
949 		if (err) {
950 			kobject_put(&filter->kobj);
951 			damon_sysfs_filters_rm_dirs(filters);
952 			return err;
953 		}
954 
955 		filters_arr[i] = filter;
956 		filters->nr++;
957 	}
958 	return 0;
959 }
960 
961 static ssize_t nr_filters_show(struct kobject *kobj,
962 		struct kobj_attribute *attr, char *buf)
963 {
964 	struct damon_sysfs_filters *filters = container_of(kobj,
965 			struct damon_sysfs_filters, kobj);
966 
967 	return sysfs_emit(buf, "%d\n", filters->nr);
968 }
969 
970 static ssize_t nr_filters_store(struct kobject *kobj,
971 		struct kobj_attribute *attr, const char *buf, size_t count)
972 {
973 	struct damon_sysfs_filters *filters;
974 	int nr, err = kstrtoint(buf, 0, &nr);
975 
976 	if (err)
977 		return err;
978 	if (nr < 0)
979 		return -EINVAL;
980 
981 	filters = container_of(kobj, struct damon_sysfs_filters, kobj);
982 
983 	if (!mutex_trylock(&damon_sysfs_lock))
984 		return -EBUSY;
985 	err = damon_sysfs_filters_add_dirs(filters, nr);
986 	mutex_unlock(&damon_sysfs_lock);
987 	if (err)
988 		return err;
989 
990 	return count;
991 }
992 
993 static void damon_sysfs_filters_release(struct kobject *kobj)
994 {
995 	kfree(container_of(kobj, struct damon_sysfs_filters, kobj));
996 }
997 
998 static struct kobj_attribute damon_sysfs_filters_nr_attr =
999 		__ATTR_RW_MODE(nr_filters, 0600);
1000 
1001 static struct attribute *damon_sysfs_filters_attrs[] = {
1002 	&damon_sysfs_filters_nr_attr.attr,
1003 	NULL,
1004 };
1005 ATTRIBUTE_GROUPS(damon_sysfs_filters);
1006 
1007 static const struct kobj_type damon_sysfs_filters_ktype = {
1008 	.release = damon_sysfs_filters_release,
1009 	.sysfs_ops = &kobj_sysfs_ops,
1010 	.default_groups = damon_sysfs_filters_groups,
1011 };
1012 
1013 /*
1014  * probe directory
1015  */
1016 
1017 struct damon_sysfs_probe {
1018 	struct kobject kobj;
1019 	struct damon_sysfs_filters *filters;
1020 };
1021 
1022 static struct damon_sysfs_probe *damon_sysfs_probe_alloc(void)
1023 {
1024 	return kzalloc_obj(struct damon_sysfs_probe);
1025 }
1026 
1027 static int damon_sysfs_probe_add_dirs(struct damon_sysfs_probe *attr)
1028 {
1029 	struct damon_sysfs_filters *filters;
1030 	int err;
1031 
1032 	filters = damon_sysfs_filters_alloc();
1033 	if (!filters)
1034 		return -ENOMEM;
1035 	attr->filters = filters;
1036 
1037 	err = kobject_init_and_add(&filters->kobj, &damon_sysfs_filters_ktype,
1038 			&attr->kobj, "filters");
1039 	if (err) {
1040 		kobject_put(&filters->kobj);
1041 		attr->filters = NULL;
1042 	}
1043 	return err;
1044 }
1045 
1046 static void damon_sysfs_probe_rm_dirs(struct damon_sysfs_probe *attr)
1047 {
1048 	if (attr->filters) {
1049 		damon_sysfs_filters_rm_dirs(attr->filters);
1050 		kobject_put(&attr->filters->kobj);
1051 	}
1052 }
1053 
1054 static void damon_sysfs_probe_release(struct kobject *kobj)
1055 {
1056 	kfree(container_of(kobj, struct damon_sysfs_probe, kobj));
1057 }
1058 
1059 static struct attribute *damon_sysfs_probe_attrs[] = {
1060 	NULL,
1061 };
1062 ATTRIBUTE_GROUPS(damon_sysfs_probe);
1063 
1064 static const struct kobj_type damon_sysfs_probe_ktype = {
1065 	.release = damon_sysfs_probe_release,
1066 	.sysfs_ops = &kobj_sysfs_ops,
1067 	.default_groups = damon_sysfs_probe_groups,
1068 };
1069 
1070 /*
1071  * probes directory
1072  */
1073 
1074 struct damon_sysfs_probes {
1075 	struct kobject kobj;
1076 	struct damon_sysfs_probe **probes_arr;
1077 	int nr;
1078 };
1079 
1080 static struct damon_sysfs_probes *damon_sysfs_probes_alloc(void)
1081 {
1082 	return kzalloc_obj(struct damon_sysfs_probes);
1083 }
1084 
1085 static void damon_sysfs_probes_rm_dirs(
1086 		struct damon_sysfs_probes *probes)
1087 {
1088 	struct damon_sysfs_probe **probes_arr = probes->probes_arr;
1089 	int i;
1090 
1091 	for (i = 0; i < probes->nr; i++) {
1092 		damon_sysfs_probe_rm_dirs(probes_arr[i]);
1093 		kobject_put(&probes_arr[i]->kobj);
1094 	}
1095 	probes->nr = 0;
1096 	kfree(probes_arr);
1097 	probes->probes_arr = NULL;
1098 }
1099 
1100 static int damon_sysfs_probes_add_dirs(
1101 		struct damon_sysfs_probes *probes, int nr_probes)
1102 {
1103 	struct damon_sysfs_probe **probes_arr, *probe;
1104 	int err, i;
1105 
1106 	damon_sysfs_probes_rm_dirs(probes);
1107 	if (!nr_probes)
1108 		return 0;
1109 
1110 	probes_arr = kmalloc_objs(*probes_arr, nr_probes,
1111 				   GFP_KERNEL | __GFP_NOWARN);
1112 	if (!probes_arr)
1113 		return -ENOMEM;
1114 	probes->probes_arr = probes_arr;
1115 
1116 	for (i = 0; i < nr_probes; i++) {
1117 		probe = damon_sysfs_probe_alloc();
1118 		if (!probe) {
1119 			damon_sysfs_probes_rm_dirs(probes);
1120 			return -ENOMEM;
1121 		}
1122 
1123 		err = kobject_init_and_add(&probe->kobj,
1124 				&damon_sysfs_probe_ktype, &probes->kobj,
1125 				"%d", i);
1126 		if (err) {
1127 			kobject_put(&probe->kobj);
1128 			damon_sysfs_probes_rm_dirs(probes);
1129 			return err;
1130 		}
1131 
1132 		err = damon_sysfs_probe_add_dirs(probe);
1133 		if (err) {
1134 			kobject_put(&probe->kobj);
1135 			damon_sysfs_probes_rm_dirs(probes);
1136 			return err;
1137 		}
1138 
1139 		probes_arr[i] = probe;
1140 		probes->nr++;
1141 	}
1142 	return 0;
1143 }
1144 
1145 static ssize_t nr_probes_show(struct kobject *kobj,
1146 		struct kobj_attribute *attr, char *buf)
1147 {
1148 	struct damon_sysfs_probes *probes = container_of(kobj,
1149 			struct damon_sysfs_probes, kobj);
1150 
1151 	return sysfs_emit(buf, "%d\n", probes->nr);
1152 }
1153 
1154 static ssize_t nr_probes_store(struct kobject *kobj,
1155 		struct kobj_attribute *attr, const char *buf, size_t count)
1156 {
1157 	struct damon_sysfs_probes *probes;
1158 	int nr, err = kstrtoint(buf, 0, &nr);
1159 
1160 	if (err)
1161 		return err;
1162 	if (nr < 0 || nr > DAMON_MAX_PROBES)
1163 		return -EINVAL;
1164 
1165 	probes = container_of(kobj, struct damon_sysfs_probes, kobj);
1166 
1167 	if (!mutex_trylock(&damon_sysfs_lock))
1168 		return -EBUSY;
1169 	err = damon_sysfs_probes_add_dirs(probes, nr);
1170 	mutex_unlock(&damon_sysfs_lock);
1171 	if (err)
1172 		return err;
1173 
1174 	return count;
1175 }
1176 
1177 static void damon_sysfs_probes_release(struct kobject *kobj)
1178 {
1179 	kfree(container_of(kobj, struct damon_sysfs_probes, kobj));
1180 }
1181 
1182 static struct kobj_attribute damon_sysfs_probes_nr_probes =
1183 		__ATTR_RW_MODE(nr_probes, 0600);
1184 
1185 static struct attribute *damon_sysfs_probes_attrs[] = {
1186 	&damon_sysfs_probes_nr_probes.attr,
1187 	NULL,
1188 };
1189 ATTRIBUTE_GROUPS(damon_sysfs_probes);
1190 
1191 static const struct kobj_type damon_sysfs_probes_ktype = {
1192 	.release = damon_sysfs_probes_release,
1193 	.sysfs_ops = &kobj_sysfs_ops,
1194 	.default_groups = damon_sysfs_probes_groups,
1195 };
1196 
1197 /*
1198  * monitoring_attrs directory
1199  */
1200 
1201 struct damon_sysfs_attrs {
1202 	struct kobject kobj;
1203 	struct damon_sysfs_intervals *intervals;
1204 	struct damon_sysfs_ul_range *nr_regions_range;
1205 	struct damon_sysfs_probes *probes;
1206 };
1207 
1208 static struct damon_sysfs_attrs *damon_sysfs_attrs_alloc(void)
1209 {
1210 	struct damon_sysfs_attrs *attrs = kmalloc_obj(*attrs);
1211 
1212 	if (!attrs)
1213 		return NULL;
1214 	attrs->kobj = (struct kobject){};
1215 	return attrs;
1216 }
1217 
1218 static int damon_sysfs_attrs_add_dirs(struct damon_sysfs_attrs *attrs)
1219 {
1220 	struct damon_sysfs_intervals *intervals;
1221 	struct damon_sysfs_ul_range *nr_regions_range;
1222 	struct damon_sysfs_probes *probes;
1223 	int err;
1224 
1225 	intervals = damon_sysfs_intervals_alloc(5000, 100000, 60000000);
1226 	if (!intervals)
1227 		return -ENOMEM;
1228 
1229 	err = kobject_init_and_add(&intervals->kobj,
1230 			&damon_sysfs_intervals_ktype, &attrs->kobj,
1231 			"intervals");
1232 	if (err)
1233 		goto put_intervals_out;
1234 	err = damon_sysfs_intervals_add_dirs(intervals);
1235 	if (err)
1236 		goto put_intervals_out;
1237 	attrs->intervals = intervals;
1238 
1239 	nr_regions_range = damon_sysfs_ul_range_alloc(10, 1000);
1240 	if (!nr_regions_range) {
1241 		err = -ENOMEM;
1242 		goto rmdir_put_intervals_out;
1243 	}
1244 
1245 	err = kobject_init_and_add(&nr_regions_range->kobj,
1246 			&damon_sysfs_ul_range_ktype, &attrs->kobj,
1247 			"nr_regions");
1248 	if (err)
1249 		goto put_nr_regions_intervals_out;
1250 	attrs->nr_regions_range = nr_regions_range;
1251 
1252 	probes = damon_sysfs_probes_alloc();
1253 	if (!probes) {
1254 		err = -ENOMEM;
1255 		goto put_nr_regions_intervals_out;
1256 	}
1257 	err = kobject_init_and_add(&probes->kobj,
1258 			&damon_sysfs_probes_ktype, &attrs->kobj, "probes");
1259 	if (err)
1260 		goto put_probes_out;
1261 	attrs->probes = probes;
1262 	return 0;
1263 
1264 put_probes_out:
1265 	kobject_put(&probes->kobj);
1266 	attrs->probes = NULL;
1267 put_nr_regions_intervals_out:
1268 	kobject_put(&nr_regions_range->kobj);
1269 	attrs->nr_regions_range = NULL;
1270 rmdir_put_intervals_out:
1271 	damon_sysfs_intervals_rm_dirs(intervals);
1272 put_intervals_out:
1273 	kobject_put(&intervals->kobj);
1274 	attrs->intervals = NULL;
1275 	return err;
1276 }
1277 
1278 static void damon_sysfs_attrs_rm_dirs(struct damon_sysfs_attrs *attrs)
1279 {
1280 	kobject_put(&attrs->nr_regions_range->kobj);
1281 	damon_sysfs_intervals_rm_dirs(attrs->intervals);
1282 	kobject_put(&attrs->intervals->kobj);
1283 	damon_sysfs_probes_rm_dirs(attrs->probes);
1284 	kobject_put(&attrs->probes->kobj);
1285 }
1286 
1287 static void damon_sysfs_attrs_release(struct kobject *kobj)
1288 {
1289 	kfree(container_of(kobj, struct damon_sysfs_attrs, kobj));
1290 }
1291 
1292 static struct attribute *damon_sysfs_attrs_attrs[] = {
1293 	NULL,
1294 };
1295 ATTRIBUTE_GROUPS(damon_sysfs_attrs);
1296 
1297 static const struct kobj_type damon_sysfs_attrs_ktype = {
1298 	.release = damon_sysfs_attrs_release,
1299 	.sysfs_ops = &kobj_sysfs_ops,
1300 	.default_groups = damon_sysfs_attrs_groups,
1301 };
1302 
1303 /*
1304  * context directory
1305  */
1306 
1307 struct damon_sysfs_ops_name {
1308 	enum damon_ops_id ops_id;
1309 	char *name;
1310 };
1311 
1312 static const struct damon_sysfs_ops_name damon_sysfs_ops_names[] = {
1313 	{
1314 		.ops_id = DAMON_OPS_VADDR,
1315 		.name = "vaddr",
1316 	},
1317 	{
1318 		.ops_id = DAMON_OPS_FVADDR,
1319 		.name = "fvaddr",
1320 	},
1321 	{
1322 		.ops_id = DAMON_OPS_PADDR,
1323 		.name = "paddr",
1324 	},
1325 };
1326 
1327 struct damon_sysfs_context {
1328 	struct kobject kobj;
1329 	enum damon_ops_id ops_id;
1330 	unsigned long addr_unit;
1331 	struct damon_sysfs_attrs *attrs;
1332 	struct damon_sysfs_targets *targets;
1333 	struct damon_sysfs_schemes *schemes;
1334 	bool pause;
1335 };
1336 
1337 static struct damon_sysfs_context *damon_sysfs_context_alloc(
1338 		enum damon_ops_id ops_id)
1339 {
1340 	struct damon_sysfs_context *context = kmalloc_obj(*context);
1341 
1342 	if (!context)
1343 		return NULL;
1344 	context->kobj = (struct kobject){};
1345 	context->ops_id = ops_id;
1346 	context->addr_unit = 1;
1347 	context->pause = false;
1348 	return context;
1349 }
1350 
1351 static int damon_sysfs_context_set_attrs(struct damon_sysfs_context *context)
1352 {
1353 	struct damon_sysfs_attrs *attrs = damon_sysfs_attrs_alloc();
1354 	int err;
1355 
1356 	if (!attrs)
1357 		return -ENOMEM;
1358 	err = kobject_init_and_add(&attrs->kobj, &damon_sysfs_attrs_ktype,
1359 			&context->kobj, "monitoring_attrs");
1360 	if (err)
1361 		goto out;
1362 	err = damon_sysfs_attrs_add_dirs(attrs);
1363 	if (err)
1364 		goto out;
1365 	context->attrs = attrs;
1366 	return 0;
1367 
1368 out:
1369 	kobject_put(&attrs->kobj);
1370 	return err;
1371 }
1372 
1373 static int damon_sysfs_context_set_targets(struct damon_sysfs_context *context)
1374 {
1375 	struct damon_sysfs_targets *targets = damon_sysfs_targets_alloc();
1376 	int err;
1377 
1378 	if (!targets)
1379 		return -ENOMEM;
1380 	err = kobject_init_and_add(&targets->kobj, &damon_sysfs_targets_ktype,
1381 			&context->kobj, "targets");
1382 	if (err) {
1383 		kobject_put(&targets->kobj);
1384 		return err;
1385 	}
1386 	context->targets = targets;
1387 	return 0;
1388 }
1389 
1390 static int damon_sysfs_context_set_schemes(struct damon_sysfs_context *context)
1391 {
1392 	struct damon_sysfs_schemes *schemes = damon_sysfs_schemes_alloc();
1393 	int err;
1394 
1395 	if (!schemes)
1396 		return -ENOMEM;
1397 	err = kobject_init_and_add(&schemes->kobj, &damon_sysfs_schemes_ktype,
1398 			&context->kobj, "schemes");
1399 	if (err) {
1400 		kobject_put(&schemes->kobj);
1401 		return err;
1402 	}
1403 	context->schemes = schemes;
1404 	return 0;
1405 }
1406 
1407 static int damon_sysfs_context_add_dirs(struct damon_sysfs_context *context)
1408 {
1409 	int err;
1410 
1411 	err = damon_sysfs_context_set_attrs(context);
1412 	if (err)
1413 		return err;
1414 
1415 	err = damon_sysfs_context_set_targets(context);
1416 	if (err)
1417 		goto rmdir_put_attrs_out;
1418 
1419 	err = damon_sysfs_context_set_schemes(context);
1420 	if (err)
1421 		goto put_targets_attrs_out;
1422 	return 0;
1423 
1424 put_targets_attrs_out:
1425 	kobject_put(&context->targets->kobj);
1426 	context->targets = NULL;
1427 rmdir_put_attrs_out:
1428 	damon_sysfs_attrs_rm_dirs(context->attrs);
1429 	kobject_put(&context->attrs->kobj);
1430 	context->attrs = NULL;
1431 	return err;
1432 }
1433 
1434 static void damon_sysfs_context_rm_dirs(struct damon_sysfs_context *context)
1435 {
1436 	damon_sysfs_attrs_rm_dirs(context->attrs);
1437 	kobject_put(&context->attrs->kobj);
1438 	damon_sysfs_targets_rm_dirs(context->targets);
1439 	kobject_put(&context->targets->kobj);
1440 	damon_sysfs_schemes_rm_dirs(context->schemes);
1441 	kobject_put(&context->schemes->kobj);
1442 }
1443 
1444 static ssize_t avail_operations_show(struct kobject *kobj,
1445 		struct kobj_attribute *attr, char *buf)
1446 {
1447 	int len = 0;
1448 	int i;
1449 
1450 	for (i = 0; i < ARRAY_SIZE(damon_sysfs_ops_names); i++) {
1451 		const struct damon_sysfs_ops_name *ops_name;
1452 
1453 		ops_name = &damon_sysfs_ops_names[i];
1454 		if (!damon_is_registered_ops(ops_name->ops_id))
1455 			continue;
1456 		len += sysfs_emit_at(buf, len, "%s\n", ops_name->name);
1457 	}
1458 	return len;
1459 }
1460 
1461 static ssize_t operations_show(struct kobject *kobj,
1462 		struct kobj_attribute *attr, char *buf)
1463 {
1464 	struct damon_sysfs_context *context = container_of(kobj,
1465 			struct damon_sysfs_context, kobj);
1466 	int i;
1467 
1468 	for (i = 0; i < ARRAY_SIZE(damon_sysfs_ops_names); i++) {
1469 		const struct damon_sysfs_ops_name *ops_name;
1470 
1471 		ops_name = &damon_sysfs_ops_names[i];
1472 		if (ops_name->ops_id == context->ops_id)
1473 			return sysfs_emit(buf, "%s\n", ops_name->name);
1474 	}
1475 	return -EINVAL;
1476 }
1477 
1478 static ssize_t operations_store(struct kobject *kobj,
1479 		struct kobj_attribute *attr, const char *buf, size_t count)
1480 {
1481 	struct damon_sysfs_context *context = container_of(kobj,
1482 			struct damon_sysfs_context, kobj);
1483 	int i;
1484 
1485 	for (i = 0; i < ARRAY_SIZE(damon_sysfs_ops_names); i++) {
1486 		const struct damon_sysfs_ops_name *ops_name;
1487 
1488 		ops_name = &damon_sysfs_ops_names[i];
1489 		if (sysfs_streq(buf, ops_name->name)) {
1490 			context->ops_id = ops_name->ops_id;
1491 			return count;
1492 		}
1493 	}
1494 	return -EINVAL;
1495 }
1496 
1497 static ssize_t addr_unit_show(struct kobject *kobj,
1498 		struct kobj_attribute *attr, char *buf)
1499 {
1500 	struct damon_sysfs_context *context = container_of(kobj,
1501 			struct damon_sysfs_context, kobj);
1502 
1503 	return sysfs_emit(buf, "%lu\n", context->addr_unit);
1504 }
1505 
1506 static ssize_t addr_unit_store(struct kobject *kobj,
1507 		struct kobj_attribute *attr, const char *buf, size_t count)
1508 {
1509 	struct damon_sysfs_context *context = container_of(kobj,
1510 			struct damon_sysfs_context, kobj);
1511 	unsigned long input_addr_unit;
1512 	int err = kstrtoul(buf, 0, &input_addr_unit);
1513 
1514 	if (err)
1515 		return err;
1516 	if (!input_addr_unit)
1517 		return -EINVAL;
1518 
1519 	context->addr_unit = input_addr_unit;
1520 	return count;
1521 }
1522 
1523 static ssize_t pause_show(struct kobject *kobj, struct kobj_attribute *attr,
1524 		char *buf)
1525 {
1526 	struct damon_sysfs_context *context = container_of(kobj,
1527 			struct damon_sysfs_context, kobj);
1528 
1529 	return sysfs_emit(buf, "%c\n", context->pause ? 'Y' : 'N');
1530 }
1531 
1532 static ssize_t pause_store(struct kobject *kobj, struct kobj_attribute *attr,
1533 		const char *buf, size_t count)
1534 {
1535 	struct damon_sysfs_context *context = container_of(kobj,
1536 			struct damon_sysfs_context, kobj);
1537 	bool pause;
1538 	int err = kstrtobool(buf, &pause);
1539 
1540 	if (err)
1541 		return err;
1542 	context->pause = pause;
1543 	return count;
1544 }
1545 
1546 
1547 static void damon_sysfs_context_release(struct kobject *kobj)
1548 {
1549 	kfree(container_of(kobj, struct damon_sysfs_context, kobj));
1550 }
1551 
1552 static struct kobj_attribute damon_sysfs_context_avail_operations_attr =
1553 		__ATTR_RO_MODE(avail_operations, 0400);
1554 
1555 static struct kobj_attribute damon_sysfs_context_operations_attr =
1556 		__ATTR_RW_MODE(operations, 0600);
1557 
1558 static struct kobj_attribute damon_sysfs_context_addr_unit_attr =
1559 		__ATTR_RW_MODE(addr_unit, 0600);
1560 
1561 static struct kobj_attribute damon_sysfs_context_pause_attr =
1562 		__ATTR_RW_MODE(pause, 0600);
1563 
1564 static struct attribute *damon_sysfs_context_attrs[] = {
1565 	&damon_sysfs_context_avail_operations_attr.attr,
1566 	&damon_sysfs_context_operations_attr.attr,
1567 	&damon_sysfs_context_addr_unit_attr.attr,
1568 	&damon_sysfs_context_pause_attr.attr,
1569 	NULL,
1570 };
1571 ATTRIBUTE_GROUPS(damon_sysfs_context);
1572 
1573 static const struct kobj_type damon_sysfs_context_ktype = {
1574 	.release = damon_sysfs_context_release,
1575 	.sysfs_ops = &kobj_sysfs_ops,
1576 	.default_groups = damon_sysfs_context_groups,
1577 };
1578 
1579 /*
1580  * contexts directory
1581  */
1582 
1583 struct damon_sysfs_contexts {
1584 	struct kobject kobj;
1585 	struct damon_sysfs_context **contexts_arr;
1586 	int nr;
1587 };
1588 
1589 static struct damon_sysfs_contexts *damon_sysfs_contexts_alloc(void)
1590 {
1591 	return kzalloc_obj(struct damon_sysfs_contexts);
1592 }
1593 
1594 static void damon_sysfs_contexts_rm_dirs(struct damon_sysfs_contexts *contexts)
1595 {
1596 	struct damon_sysfs_context **contexts_arr = contexts->contexts_arr;
1597 	int i;
1598 
1599 	for (i = 0; i < contexts->nr; i++) {
1600 		damon_sysfs_context_rm_dirs(contexts_arr[i]);
1601 		kobject_put(&contexts_arr[i]->kobj);
1602 	}
1603 	contexts->nr = 0;
1604 	kfree(contexts_arr);
1605 	contexts->contexts_arr = NULL;
1606 }
1607 
1608 static int damon_sysfs_contexts_add_dirs(struct damon_sysfs_contexts *contexts,
1609 		int nr_contexts)
1610 {
1611 	struct damon_sysfs_context **contexts_arr, *context;
1612 	int err, i;
1613 
1614 	damon_sysfs_contexts_rm_dirs(contexts);
1615 	if (!nr_contexts)
1616 		return 0;
1617 
1618 	contexts_arr = kmalloc_objs(*contexts_arr, nr_contexts,
1619 				    GFP_KERNEL | __GFP_NOWARN);
1620 	if (!contexts_arr)
1621 		return -ENOMEM;
1622 	contexts->contexts_arr = contexts_arr;
1623 
1624 	for (i = 0; i < nr_contexts; i++) {
1625 		context = damon_sysfs_context_alloc(DAMON_OPS_VADDR);
1626 		if (!context) {
1627 			damon_sysfs_contexts_rm_dirs(contexts);
1628 			return -ENOMEM;
1629 		}
1630 
1631 		err = kobject_init_and_add(&context->kobj,
1632 				&damon_sysfs_context_ktype, &contexts->kobj,
1633 				"%d", i);
1634 		if (err)
1635 			goto out;
1636 
1637 		err = damon_sysfs_context_add_dirs(context);
1638 		if (err)
1639 			goto out;
1640 
1641 		contexts_arr[i] = context;
1642 		contexts->nr++;
1643 	}
1644 	return 0;
1645 
1646 out:
1647 	damon_sysfs_contexts_rm_dirs(contexts);
1648 	kobject_put(&context->kobj);
1649 	return err;
1650 }
1651 
1652 static ssize_t nr_contexts_show(struct kobject *kobj,
1653 		struct kobj_attribute *attr, char *buf)
1654 {
1655 	struct damon_sysfs_contexts *contexts = container_of(kobj,
1656 			struct damon_sysfs_contexts, kobj);
1657 
1658 	return sysfs_emit(buf, "%d\n", contexts->nr);
1659 }
1660 
1661 static ssize_t nr_contexts_store(struct kobject *kobj,
1662 		struct kobj_attribute *attr, const char *buf, size_t count)
1663 {
1664 	struct damon_sysfs_contexts *contexts;
1665 	int nr, err;
1666 
1667 	err = kstrtoint(buf, 0, &nr);
1668 	if (err)
1669 		return err;
1670 	/* TODO: support multiple contexts per kdamond */
1671 	if (nr < 0 || 1 < nr)
1672 		return -EINVAL;
1673 
1674 	contexts = container_of(kobj, struct damon_sysfs_contexts, kobj);
1675 	if (!mutex_trylock(&damon_sysfs_lock))
1676 		return -EBUSY;
1677 	err = damon_sysfs_contexts_add_dirs(contexts, nr);
1678 	mutex_unlock(&damon_sysfs_lock);
1679 	if (err)
1680 		return err;
1681 
1682 	return count;
1683 }
1684 
1685 static void damon_sysfs_contexts_release(struct kobject *kobj)
1686 {
1687 	kfree(container_of(kobj, struct damon_sysfs_contexts, kobj));
1688 }
1689 
1690 static struct kobj_attribute damon_sysfs_contexts_nr_attr
1691 		= __ATTR_RW_MODE(nr_contexts, 0600);
1692 
1693 static struct attribute *damon_sysfs_contexts_attrs[] = {
1694 	&damon_sysfs_contexts_nr_attr.attr,
1695 	NULL,
1696 };
1697 ATTRIBUTE_GROUPS(damon_sysfs_contexts);
1698 
1699 static const struct kobj_type damon_sysfs_contexts_ktype = {
1700 	.release = damon_sysfs_contexts_release,
1701 	.sysfs_ops = &kobj_sysfs_ops,
1702 	.default_groups = damon_sysfs_contexts_groups,
1703 };
1704 
1705 /*
1706  * kdamond directory
1707  */
1708 
1709 struct damon_sysfs_kdamond {
1710 	struct kobject kobj;
1711 	struct damon_sysfs_contexts *contexts;
1712 	struct damon_ctx *damon_ctx;
1713 	unsigned int refresh_ms;
1714 };
1715 
1716 static struct damon_sysfs_kdamond *damon_sysfs_kdamond_alloc(void)
1717 {
1718 	return kzalloc_obj(struct damon_sysfs_kdamond);
1719 }
1720 
1721 static int damon_sysfs_kdamond_add_dirs(struct damon_sysfs_kdamond *kdamond)
1722 {
1723 	struct damon_sysfs_contexts *contexts;
1724 	int err;
1725 
1726 	contexts = damon_sysfs_contexts_alloc();
1727 	if (!contexts)
1728 		return -ENOMEM;
1729 
1730 	err = kobject_init_and_add(&contexts->kobj,
1731 			&damon_sysfs_contexts_ktype, &kdamond->kobj,
1732 			"contexts");
1733 	if (err) {
1734 		kobject_put(&contexts->kobj);
1735 		return err;
1736 	}
1737 	kdamond->contexts = contexts;
1738 
1739 	return err;
1740 }
1741 
1742 static void damon_sysfs_kdamond_rm_dirs(struct damon_sysfs_kdamond *kdamond)
1743 {
1744 	damon_sysfs_contexts_rm_dirs(kdamond->contexts);
1745 	kobject_put(&kdamond->contexts->kobj);
1746 }
1747 
1748 /*
1749  * enum damon_sysfs_cmd - Commands for a specific kdamond.
1750  */
1751 enum damon_sysfs_cmd {
1752 	/* @DAMON_SYSFS_CMD_ON: Turn the kdamond on. */
1753 	DAMON_SYSFS_CMD_ON,
1754 	/* @DAMON_SYSFS_CMD_OFF: Turn the kdamond off. */
1755 	DAMON_SYSFS_CMD_OFF,
1756 	/* @DAMON_SYSFS_CMD_COMMIT: Update kdamond inputs. */
1757 	DAMON_SYSFS_CMD_COMMIT,
1758 	/*
1759 	 * @DAMON_SYSFS_CMD_COMMIT_SCHEMES_QUOTA_GOALS: Commit the quota goals
1760 	 * to DAMON.
1761 	 */
1762 	DAMON_SYSFS_CMD_COMMIT_SCHEMES_QUOTA_GOALS,
1763 	/*
1764 	 * @DAMON_SYSFS_CMD_UPDATE_SCHEMES_STATS: Update scheme stats sysfs
1765 	 * files.
1766 	 */
1767 	DAMON_SYSFS_CMD_UPDATE_SCHEMES_STATS,
1768 	/*
1769 	 * @DAMON_SYSFS_CMD_UPDATE_SCHEMES_TRIED_BYTES: Update
1770 	 * tried_regions/total_bytes sysfs files for each scheme.
1771 	 */
1772 	DAMON_SYSFS_CMD_UPDATE_SCHEMES_TRIED_BYTES,
1773 	/*
1774 	 * @DAMON_SYSFS_CMD_UPDATE_SCHEMES_TRIED_REGIONS: Update schemes tried
1775 	 * regions
1776 	 */
1777 	DAMON_SYSFS_CMD_UPDATE_SCHEMES_TRIED_REGIONS,
1778 	/*
1779 	 * @DAMON_SYSFS_CMD_CLEAR_SCHEMES_TRIED_REGIONS: Clear schemes tried
1780 	 * regions
1781 	 */
1782 	DAMON_SYSFS_CMD_CLEAR_SCHEMES_TRIED_REGIONS,
1783 	/*
1784 	 * @DAMON_SYSFS_CMD_UPDATE_SCHEMES_EFFECTIVE_QUOTAS: Update the
1785 	 * effective size quota of the scheme in bytes.
1786 	 */
1787 	DAMON_SYSFS_CMD_UPDATE_SCHEMES_EFFECTIVE_QUOTAS,
1788 	/*
1789 	 * @DAMON_SYSFS_CMD_UPDATE_TUNED_INTERVALS: Update the tuned monitoring
1790 	 * intervals.
1791 	 */
1792 	DAMON_SYSFS_CMD_UPDATE_TUNED_INTERVALS,
1793 	/*
1794 	 * @NR_DAMON_SYSFS_CMDS: Total number of DAMON sysfs commands.
1795 	 */
1796 	NR_DAMON_SYSFS_CMDS,
1797 };
1798 
1799 /* Should match with enum damon_sysfs_cmd */
1800 static const char * const damon_sysfs_cmd_strs[] = {
1801 	"on",
1802 	"off",
1803 	"commit",
1804 	"commit_schemes_quota_goals",
1805 	"update_schemes_stats",
1806 	"update_schemes_tried_bytes",
1807 	"update_schemes_tried_regions",
1808 	"clear_schemes_tried_regions",
1809 	"update_schemes_effective_quotas",
1810 	"update_tuned_intervals",
1811 };
1812 
1813 static ssize_t state_show(struct kobject *kobj, struct kobj_attribute *attr,
1814 		char *buf)
1815 {
1816 	struct damon_sysfs_kdamond *kdamond = container_of(kobj,
1817 			struct damon_sysfs_kdamond, kobj);
1818 	struct damon_ctx *ctx;
1819 	bool running = false;
1820 
1821 	if (!mutex_trylock(&damon_sysfs_lock))
1822 		return -EBUSY;
1823 
1824 	ctx = kdamond->damon_ctx;
1825 	if (ctx)
1826 		running = damon_is_running(ctx);
1827 
1828 	mutex_unlock(&damon_sysfs_lock);
1829 
1830 	return sysfs_emit(buf, "%s\n", running ?
1831 			damon_sysfs_cmd_strs[DAMON_SYSFS_CMD_ON] :
1832 			damon_sysfs_cmd_strs[DAMON_SYSFS_CMD_OFF]);
1833 }
1834 
1835 static int damon_sysfs_set_attrs(struct damon_ctx *ctx,
1836 		struct damon_sysfs_attrs *sys_attrs)
1837 {
1838 	struct damon_sysfs_intervals *sys_intervals = sys_attrs->intervals;
1839 	struct damon_sysfs_intervals_goal *sys_goal =
1840 		sys_intervals->intervals_goal;
1841 	struct damon_sysfs_ul_range *sys_nr_regions =
1842 		sys_attrs->nr_regions_range;
1843 	struct damon_attrs attrs = {
1844 		.sample_interval = sys_intervals->sample_us,
1845 		.aggr_interval = sys_intervals->aggr_us,
1846 		.intervals_goal = {
1847 			.access_bp = sys_goal->access_bp,
1848 			.aggrs = sys_goal->aggrs,
1849 			.min_sample_us = sys_goal->min_sample_us,
1850 			.max_sample_us = sys_goal->max_sample_us},
1851 		.ops_update_interval = sys_intervals->update_us,
1852 		.min_nr_regions = sys_nr_regions->min,
1853 		.max_nr_regions = sys_nr_regions->max,
1854 	};
1855 	return damon_set_attrs(ctx, &attrs);
1856 }
1857 
1858 static int damon_sysfs_set_probes(struct damon_ctx *ctx,
1859 		struct damon_sysfs_probes *sys_probes)
1860 {
1861 	int i;
1862 
1863 	for (i = 0; i < sys_probes->nr; i++) {
1864 		struct damon_sysfs_filters *sys_filters =
1865 			sys_probes->probes_arr[i]->filters;
1866 		struct damon_probe *c;
1867 		int j;
1868 
1869 		if (!sys_filters)
1870 			continue;
1871 		c = damon_new_probe();
1872 		if (!c)
1873 			return -ENOMEM;
1874 		damon_add_probe(ctx, c);
1875 
1876 		for (j = 0; j < sys_filters->nr; j++) {
1877 			struct damon_sysfs_filter *sys_filter =
1878 				sys_filters->filters_arr[j];
1879 			struct damon_filter *filter;
1880 
1881 			filter = damon_new_filter(sys_filter->type,
1882 					sys_filter->matching,
1883 					sys_filter->allow);
1884 			if (!filter)
1885 				return -ENOMEM;
1886 			damon_add_filter(c, filter);
1887 		}
1888 	}
1889 	return 0;
1890 }
1891 
1892 static int damon_sysfs_set_regions(struct damon_target *t,
1893 		struct damon_sysfs_regions *sysfs_regions,
1894 		unsigned long min_region_sz)
1895 {
1896 	struct damon_addr_range *ranges = kmalloc_objs(*ranges,
1897 						       sysfs_regions->nr,
1898 						       GFP_KERNEL | __GFP_NOWARN);
1899 	int i, err = -EINVAL;
1900 
1901 	if (!ranges)
1902 		return -ENOMEM;
1903 	for (i = 0; i < sysfs_regions->nr; i++) {
1904 		struct damon_sysfs_region *sys_region =
1905 			sysfs_regions->regions_arr[i];
1906 
1907 		if (sys_region->ar.start > sys_region->ar.end)
1908 			goto out;
1909 
1910 		ranges[i].start = sys_region->ar.start;
1911 		ranges[i].end = sys_region->ar.end;
1912 		if (i == 0)
1913 			continue;
1914 		if (ranges[i - 1].end > ranges[i].start)
1915 			goto out;
1916 	}
1917 	err = damon_set_regions(t, ranges, sysfs_regions->nr, min_region_sz);
1918 out:
1919 	kfree(ranges);
1920 	return err;
1921 
1922 }
1923 
1924 static int damon_sysfs_add_target(struct damon_sysfs_target *sys_target,
1925 		struct damon_ctx *ctx)
1926 {
1927 	struct damon_target *t = damon_new_target();
1928 
1929 	if (!t)
1930 		return -ENOMEM;
1931 	damon_add_target(ctx, t);
1932 	if (damon_target_has_pid(ctx)) {
1933 		t->pid = find_get_pid(sys_target->pid);
1934 		if (!t->pid)
1935 			/* caller will destroy targets */
1936 			return -EINVAL;
1937 	}
1938 	t->obsolete = sys_target->obsolete;
1939 	return damon_sysfs_set_regions(t, sys_target->regions,
1940 			ctx->min_region_sz);
1941 }
1942 
1943 static int damon_sysfs_add_targets(struct damon_ctx *ctx,
1944 		struct damon_sysfs_targets *sysfs_targets)
1945 {
1946 	int i, err;
1947 
1948 	/* Multiple physical address space monitoring targets makes no sense */
1949 	if (ctx->ops.id == DAMON_OPS_PADDR && sysfs_targets->nr > 1)
1950 		return -EINVAL;
1951 
1952 	for (i = 0; i < sysfs_targets->nr; i++) {
1953 		struct damon_sysfs_target *st = sysfs_targets->targets_arr[i];
1954 
1955 		err = damon_sysfs_add_target(st, ctx);
1956 		if (err)
1957 			return err;
1958 	}
1959 	return 0;
1960 }
1961 
1962 /*
1963  * damon_sysfs_upd_schemes_stats() - Update schemes stats sysfs files.
1964  * @data:	The kobject wrapper that associated to the kdamond thread.
1965  *
1966  * This function reads the schemes stats of specific kdamond and update the
1967  * related values for sysfs files.  This function should be called from DAMON
1968  * worker thread,to safely access the DAMON contexts-internal data.  Caller
1969  * should also ensure holding ``damon_syfs_lock``, and ->damon_ctx of @data is
1970  * not NULL but a valid pointer, to safely access DAMON sysfs variables.
1971  */
1972 static int damon_sysfs_upd_schemes_stats(void *data)
1973 {
1974 	struct damon_sysfs_kdamond *kdamond = data;
1975 	struct damon_ctx *ctx = kdamond->damon_ctx;
1976 
1977 	damon_sysfs_schemes_update_stats(
1978 			kdamond->contexts->contexts_arr[0]->schemes, ctx);
1979 	return 0;
1980 }
1981 
1982 static inline bool damon_sysfs_kdamond_running(
1983 		struct damon_sysfs_kdamond *kdamond)
1984 {
1985 	return kdamond->damon_ctx &&
1986 		damon_is_running(kdamond->damon_ctx);
1987 }
1988 
1989 static int damon_sysfs_apply_inputs(struct damon_ctx *ctx,
1990 		struct damon_sysfs_context *sys_ctx)
1991 {
1992 	int err;
1993 
1994 	err = damon_select_ops(ctx, sys_ctx->ops_id);
1995 	if (err)
1996 		return err;
1997 	ctx->addr_unit = sys_ctx->addr_unit;
1998 	/* addr_unit is respected by only DAMON_OPS_PADDR */
1999 	if (sys_ctx->ops_id == DAMON_OPS_PADDR)
2000 		ctx->min_region_sz = max(
2001 				DAMON_MIN_REGION_SZ / sys_ctx->addr_unit, 1);
2002 	ctx->pause = sys_ctx->pause;
2003 	err = damon_sysfs_set_attrs(ctx, sys_ctx->attrs);
2004 	if (err)
2005 		return err;
2006 	err = damon_sysfs_set_probes(ctx, sys_ctx->attrs->probes);
2007 	if (err)
2008 		return err;
2009 	err = damon_sysfs_add_targets(ctx, sys_ctx->targets);
2010 	if (err)
2011 		return err;
2012 	return damon_sysfs_add_schemes(ctx, sys_ctx->schemes);
2013 }
2014 
2015 static struct damon_ctx *damon_sysfs_build_ctx(
2016 		struct damon_sysfs_context *sys_ctx);
2017 
2018 /*
2019  * Return a new damon_ctx for testing new parameters to commit.
2020  */
2021 static struct damon_ctx *damon_sysfs_new_test_ctx(
2022 		struct damon_ctx *running_ctx)
2023 {
2024 	struct damon_ctx *test_ctx;
2025 	int err;
2026 
2027 	test_ctx = damon_new_ctx();
2028 	if (!test_ctx)
2029 		return NULL;
2030 	err = damon_commit_ctx(test_ctx, running_ctx);
2031 	if (err) {
2032 		damon_destroy_ctx(test_ctx);
2033 		return NULL;
2034 	}
2035 	return test_ctx;
2036 }
2037 
2038 /*
2039  * damon_sysfs_commit_input() - Commit user inputs to a running kdamond.
2040  * @kdamond:	The kobject wrapper for the associated kdamond.
2041  *
2042  * Returns error if the sysfs input is wrong.
2043  */
2044 static int damon_sysfs_commit_input(void *data)
2045 {
2046 	struct damon_sysfs_kdamond *kdamond = data;
2047 	struct damon_ctx *param_ctx, *test_ctx;
2048 	int err;
2049 
2050 	if (!damon_sysfs_kdamond_running(kdamond))
2051 		return -EINVAL;
2052 	/* TODO: Support multiple contexts per kdamond */
2053 	if (kdamond->contexts->nr != 1)
2054 		return -EINVAL;
2055 
2056 	param_ctx = damon_sysfs_build_ctx(kdamond->contexts->contexts_arr[0]);
2057 	if (IS_ERR(param_ctx))
2058 		return PTR_ERR(param_ctx);
2059 	test_ctx = damon_sysfs_new_test_ctx(kdamond->damon_ctx);
2060 	if (!test_ctx) {
2061 		damon_destroy_ctx(param_ctx);
2062 		return -ENOMEM;
2063 	}
2064 	err = damon_commit_ctx(test_ctx, param_ctx);
2065 	if (err)
2066 		goto out;
2067 	err = damon_commit_ctx(kdamond->damon_ctx, param_ctx);
2068 out:
2069 	damon_destroy_ctx(test_ctx);
2070 	damon_destroy_ctx(param_ctx);
2071 	return err;
2072 }
2073 
2074 static int damon_sysfs_commit_schemes_quota_goals(void *data)
2075 {
2076 	struct damon_sysfs_kdamond *sysfs_kdamond = data;
2077 	struct damon_ctx *ctx;
2078 	struct damon_sysfs_context *sysfs_ctx;
2079 
2080 	if (!damon_sysfs_kdamond_running(sysfs_kdamond))
2081 		return -EINVAL;
2082 	/* TODO: Support multiple contexts per kdamond */
2083 	if (sysfs_kdamond->contexts->nr != 1)
2084 		return -EINVAL;
2085 
2086 	ctx = sysfs_kdamond->damon_ctx;
2087 	sysfs_ctx = sysfs_kdamond->contexts->contexts_arr[0];
2088 	return damos_sysfs_set_quota_scores(sysfs_ctx->schemes, ctx);
2089 }
2090 
2091 /*
2092  * damon_sysfs_upd_schemes_effective_quotas() - Update schemes effective quotas
2093  * sysfs files.
2094  * @data:	The kobject wrapper that associated to the kdamond thread.
2095  *
2096  * This function reads the schemes' effective quotas of specific kdamond and
2097  * update the related values for sysfs files.  This function should be called
2098  * from DAMON callbacks while holding ``damon_syfs_lock``, to safely access the
2099  * DAMON contexts-internal data and DAMON sysfs variables.
2100  */
2101 static int damon_sysfs_upd_schemes_effective_quotas(void *data)
2102 {
2103 	struct damon_sysfs_kdamond *kdamond = data;
2104 	struct damon_ctx *ctx = kdamond->damon_ctx;
2105 
2106 	damos_sysfs_update_effective_quotas(
2107 			kdamond->contexts->contexts_arr[0]->schemes, ctx);
2108 	return 0;
2109 }
2110 
2111 static int damon_sysfs_upd_tuned_intervals(void *data)
2112 {
2113 	struct damon_sysfs_kdamond *kdamond = data;
2114 	struct damon_ctx *ctx = kdamond->damon_ctx;
2115 
2116 	kdamond->contexts->contexts_arr[0]->attrs->intervals->sample_us =
2117 		ctx->attrs.sample_interval;
2118 	kdamond->contexts->contexts_arr[0]->attrs->intervals->aggr_us =
2119 		ctx->attrs.aggr_interval;
2120 	return 0;
2121 }
2122 
2123 static struct damon_ctx *damon_sysfs_build_ctx(
2124 		struct damon_sysfs_context *sys_ctx)
2125 {
2126 	struct damon_ctx *ctx = damon_new_ctx();
2127 	int err;
2128 
2129 	if (!ctx)
2130 		return ERR_PTR(-ENOMEM);
2131 
2132 	err = damon_sysfs_apply_inputs(ctx, sys_ctx);
2133 	if (err) {
2134 		damon_destroy_ctx(ctx);
2135 		return ERR_PTR(err);
2136 	}
2137 
2138 	return ctx;
2139 }
2140 
2141 static unsigned long damon_sysfs_next_update_jiffies;
2142 
2143 static int damon_sysfs_repeat_call_fn(void *data)
2144 {
2145 	struct damon_sysfs_kdamond *sysfs_kdamond = data;
2146 
2147 	if (!sysfs_kdamond->refresh_ms)
2148 		return 0;
2149 	if (time_before(jiffies, damon_sysfs_next_update_jiffies))
2150 		return 0;
2151 	damon_sysfs_next_update_jiffies = jiffies +
2152 		msecs_to_jiffies(sysfs_kdamond->refresh_ms);
2153 
2154 	if (!mutex_trylock(&damon_sysfs_lock))
2155 		return 0;
2156 	if (sysfs_kdamond->contexts->nr != 1)
2157 		goto out;
2158 	damon_sysfs_upd_tuned_intervals(sysfs_kdamond);
2159 	damon_sysfs_upd_schemes_stats(sysfs_kdamond);
2160 	damon_sysfs_upd_schemes_effective_quotas(sysfs_kdamond);
2161 out:
2162 	mutex_unlock(&damon_sysfs_lock);
2163 	return 0;
2164 }
2165 
2166 static int damon_sysfs_turn_damon_on(struct damon_sysfs_kdamond *kdamond)
2167 {
2168 	struct damon_ctx *ctx;
2169 	struct damon_call_control *repeat_call_control;
2170 	int err;
2171 
2172 	if (damon_sysfs_kdamond_running(kdamond))
2173 		return -EBUSY;
2174 	/* TODO: support multiple contexts per kdamond */
2175 	if (kdamond->contexts->nr != 1)
2176 		return -EINVAL;
2177 
2178 	if (kdamond->damon_ctx)
2179 		damon_destroy_ctx(kdamond->damon_ctx);
2180 	kdamond->damon_ctx = NULL;
2181 
2182 	repeat_call_control = kmalloc_obj(*repeat_call_control);
2183 	if (!repeat_call_control)
2184 		return -ENOMEM;
2185 
2186 	ctx = damon_sysfs_build_ctx(kdamond->contexts->contexts_arr[0]);
2187 	if (IS_ERR(ctx)) {
2188 		kfree(repeat_call_control);
2189 		return PTR_ERR(ctx);
2190 	}
2191 	err = damon_start(&ctx, 1, false);
2192 	if (err) {
2193 		kfree(repeat_call_control);
2194 		damon_destroy_ctx(ctx);
2195 		return err;
2196 	}
2197 	kdamond->damon_ctx = ctx;
2198 
2199 	damon_sysfs_next_update_jiffies =
2200 		jiffies + msecs_to_jiffies(kdamond->refresh_ms);
2201 
2202 	repeat_call_control->fn = damon_sysfs_repeat_call_fn;
2203 	repeat_call_control->data = kdamond;
2204 	repeat_call_control->repeat = true;
2205 	repeat_call_control->dealloc_on_cancel = true;
2206 	if (damon_call(ctx, repeat_call_control))
2207 		kfree(repeat_call_control);
2208 	return err;
2209 }
2210 
2211 static int damon_sysfs_turn_damon_off(struct damon_sysfs_kdamond *kdamond)
2212 {
2213 	if (!kdamond->damon_ctx)
2214 		return -EINVAL;
2215 	return damon_stop(&kdamond->damon_ctx, 1);
2216 	/*
2217 	 * To allow users show final monitoring results of already turned-off
2218 	 * DAMON, we free kdamond->damon_ctx in next
2219 	 * damon_sysfs_turn_damon_on(), or kdamonds_nr_store()
2220 	 */
2221 }
2222 
2223 static int damon_sysfs_damon_call(int (*fn)(void *data),
2224 		struct damon_sysfs_kdamond *kdamond)
2225 {
2226 	struct damon_call_control call_control = {};
2227 	int err;
2228 
2229 	if (!kdamond->damon_ctx)
2230 		return -EINVAL;
2231 	call_control.fn = fn;
2232 	call_control.data = kdamond;
2233 	err = damon_call(kdamond->damon_ctx, &call_control);
2234 	return err ? err : call_control.return_code;
2235 }
2236 
2237 struct damon_sysfs_schemes_walk_data {
2238 	struct damon_sysfs_kdamond *sysfs_kdamond;
2239 	bool total_bytes_only;
2240 };
2241 
2242 /* populate the region directory */
2243 static void damon_sysfs_schemes_tried_regions_upd_one(void *data, struct damon_ctx *ctx,
2244 		struct damon_target *t, struct damon_region *r,
2245 		struct damos *s, unsigned long sz_filter_passed)
2246 {
2247 	struct damon_sysfs_schemes_walk_data *walk_data = data;
2248 	struct damon_sysfs_kdamond *sysfs_kdamond = walk_data->sysfs_kdamond;
2249 
2250 	damos_sysfs_populate_region_dir(
2251 			sysfs_kdamond->contexts->contexts_arr[0]->schemes,
2252 			ctx, t, r, s, walk_data->total_bytes_only,
2253 			sz_filter_passed);
2254 }
2255 
2256 static int damon_sysfs_update_schemes_tried_regions(
2257 		struct damon_sysfs_kdamond *sysfs_kdamond, bool total_bytes_only)
2258 {
2259 	struct damon_sysfs_schemes_walk_data walk_data = {
2260 		.sysfs_kdamond = sysfs_kdamond,
2261 		.total_bytes_only = total_bytes_only,
2262 	};
2263 	struct damos_walk_control control = {
2264 		.walk_fn = damon_sysfs_schemes_tried_regions_upd_one,
2265 		.data = &walk_data,
2266 	};
2267 	struct damon_ctx *ctx = sysfs_kdamond->damon_ctx;
2268 
2269 	if (!ctx)
2270 		return -EINVAL;
2271 
2272 	damon_sysfs_schemes_clear_regions(
2273 			sysfs_kdamond->contexts->contexts_arr[0]->schemes);
2274 	return damos_walk(ctx, &control);
2275 }
2276 
2277 /*
2278  * damon_sysfs_handle_cmd() - Handle a command for a specific kdamond.
2279  * @cmd:	The command to handle.
2280  * @kdamond:	The kobject wrapper for the associated kdamond.
2281  *
2282  * This function handles a DAMON sysfs command for a kdamond.
2283  *
2284  * Return: 0 on success, negative error code otherwise.
2285  */
2286 static int damon_sysfs_handle_cmd(enum damon_sysfs_cmd cmd,
2287 		struct damon_sysfs_kdamond *kdamond)
2288 {
2289 	if (cmd != DAMON_SYSFS_CMD_OFF && kdamond->contexts->nr != 1)
2290 		return -EINVAL;
2291 
2292 	switch (cmd) {
2293 	case DAMON_SYSFS_CMD_ON:
2294 		return damon_sysfs_turn_damon_on(kdamond);
2295 	case DAMON_SYSFS_CMD_OFF:
2296 		return damon_sysfs_turn_damon_off(kdamond);
2297 	case DAMON_SYSFS_CMD_COMMIT:
2298 		return damon_sysfs_damon_call(
2299 				damon_sysfs_commit_input, kdamond);
2300 	case DAMON_SYSFS_CMD_COMMIT_SCHEMES_QUOTA_GOALS:
2301 		return damon_sysfs_damon_call(
2302 				damon_sysfs_commit_schemes_quota_goals,
2303 				kdamond);
2304 	case DAMON_SYSFS_CMD_UPDATE_SCHEMES_STATS:
2305 		return damon_sysfs_damon_call(
2306 				damon_sysfs_upd_schemes_stats, kdamond);
2307 	case DAMON_SYSFS_CMD_UPDATE_SCHEMES_TRIED_BYTES:
2308 		return damon_sysfs_update_schemes_tried_regions(kdamond, true);
2309 	case DAMON_SYSFS_CMD_UPDATE_SCHEMES_TRIED_REGIONS:
2310 		return damon_sysfs_update_schemes_tried_regions(kdamond, false);
2311 	case DAMON_SYSFS_CMD_CLEAR_SCHEMES_TRIED_REGIONS:
2312 		return damon_sysfs_schemes_clear_regions(
2313 			kdamond->contexts->contexts_arr[0]->schemes);
2314 	case DAMON_SYSFS_CMD_UPDATE_SCHEMES_EFFECTIVE_QUOTAS:
2315 		return damon_sysfs_damon_call(
2316 				damon_sysfs_upd_schemes_effective_quotas,
2317 				kdamond);
2318 	case DAMON_SYSFS_CMD_UPDATE_TUNED_INTERVALS:
2319 		return damon_sysfs_damon_call(
2320 				damon_sysfs_upd_tuned_intervals, kdamond);
2321 	default:
2322 		return -EINVAL;
2323 	}
2324 }
2325 
2326 static ssize_t state_store(struct kobject *kobj, struct kobj_attribute *attr,
2327 		const char *buf, size_t count)
2328 {
2329 	struct damon_sysfs_kdamond *kdamond = container_of(kobj,
2330 			struct damon_sysfs_kdamond, kobj);
2331 	enum damon_sysfs_cmd cmd;
2332 	ssize_t ret = -EINVAL;
2333 
2334 	if (!mutex_trylock(&damon_sysfs_lock))
2335 		return -EBUSY;
2336 	for (cmd = 0; cmd < NR_DAMON_SYSFS_CMDS; cmd++) {
2337 		if (sysfs_streq(buf, damon_sysfs_cmd_strs[cmd])) {
2338 			ret = damon_sysfs_handle_cmd(cmd, kdamond);
2339 			break;
2340 		}
2341 	}
2342 	mutex_unlock(&damon_sysfs_lock);
2343 	if (!ret)
2344 		ret = count;
2345 	return ret;
2346 }
2347 
2348 static ssize_t pid_show(struct kobject *kobj,
2349 		struct kobj_attribute *attr, char *buf)
2350 {
2351 	struct damon_sysfs_kdamond *kdamond = container_of(kobj,
2352 			struct damon_sysfs_kdamond, kobj);
2353 	struct damon_ctx *ctx;
2354 	int pid = -1;
2355 
2356 	if (!mutex_trylock(&damon_sysfs_lock))
2357 		return -EBUSY;
2358 	ctx = kdamond->damon_ctx;
2359 	if (!ctx)
2360 		goto out;
2361 
2362 	pid = damon_kdamond_pid(ctx);
2363 	if (pid < 0)
2364 		pid = -1;
2365 out:
2366 	mutex_unlock(&damon_sysfs_lock);
2367 	return sysfs_emit(buf, "%d\n", pid);
2368 }
2369 
2370 static ssize_t refresh_ms_show(struct kobject *kobj,
2371 		struct kobj_attribute *attr, char *buf)
2372 {
2373 	struct damon_sysfs_kdamond *kdamond = container_of(kobj,
2374 			struct damon_sysfs_kdamond, kobj);
2375 
2376 	return sysfs_emit(buf, "%u\n", kdamond->refresh_ms);
2377 }
2378 
2379 static ssize_t refresh_ms_store(struct kobject *kobj,
2380 		struct kobj_attribute *attr, const char *buf, size_t count)
2381 {
2382 	struct damon_sysfs_kdamond *kdamond = container_of(kobj,
2383 			struct damon_sysfs_kdamond, kobj);
2384 	unsigned int nr;
2385 	int err = kstrtouint(buf, 0, &nr);
2386 
2387 	if (err)
2388 		return err;
2389 
2390 	kdamond->refresh_ms = nr;
2391 	return count;
2392 }
2393 
2394 static void damon_sysfs_kdamond_release(struct kobject *kobj)
2395 {
2396 	struct damon_sysfs_kdamond *kdamond = container_of(kobj,
2397 			struct damon_sysfs_kdamond, kobj);
2398 
2399 	if (kdamond->damon_ctx)
2400 		damon_destroy_ctx(kdamond->damon_ctx);
2401 	kfree(kdamond);
2402 }
2403 
2404 static struct kobj_attribute damon_sysfs_kdamond_state_attr =
2405 		__ATTR_RW_MODE(state, 0600);
2406 
2407 static struct kobj_attribute damon_sysfs_kdamond_pid_attr =
2408 		__ATTR_RO_MODE(pid, 0400);
2409 
2410 static struct kobj_attribute damon_sysfs_kdamond_refresh_ms_attr =
2411 		__ATTR_RW_MODE(refresh_ms, 0600);
2412 
2413 static struct attribute *damon_sysfs_kdamond_attrs[] = {
2414 	&damon_sysfs_kdamond_state_attr.attr,
2415 	&damon_sysfs_kdamond_pid_attr.attr,
2416 	&damon_sysfs_kdamond_refresh_ms_attr.attr,
2417 	NULL,
2418 };
2419 ATTRIBUTE_GROUPS(damon_sysfs_kdamond);
2420 
2421 static const struct kobj_type damon_sysfs_kdamond_ktype = {
2422 	.release = damon_sysfs_kdamond_release,
2423 	.sysfs_ops = &kobj_sysfs_ops,
2424 	.default_groups = damon_sysfs_kdamond_groups,
2425 };
2426 
2427 /*
2428  * kdamonds directory
2429  */
2430 
2431 struct damon_sysfs_kdamonds {
2432 	struct kobject kobj;
2433 	struct damon_sysfs_kdamond **kdamonds_arr;
2434 	int nr;
2435 };
2436 
2437 static struct damon_sysfs_kdamonds *damon_sysfs_kdamonds_alloc(void)
2438 {
2439 	return kzalloc_obj(struct damon_sysfs_kdamonds);
2440 }
2441 
2442 static void damon_sysfs_kdamonds_rm_dirs(struct damon_sysfs_kdamonds *kdamonds)
2443 {
2444 	struct damon_sysfs_kdamond **kdamonds_arr = kdamonds->kdamonds_arr;
2445 	int i;
2446 
2447 	for (i = 0; i < kdamonds->nr; i++) {
2448 		damon_sysfs_kdamond_rm_dirs(kdamonds_arr[i]);
2449 		kobject_put(&kdamonds_arr[i]->kobj);
2450 	}
2451 	kdamonds->nr = 0;
2452 	kfree(kdamonds_arr);
2453 	kdamonds->kdamonds_arr = NULL;
2454 }
2455 
2456 static bool damon_sysfs_kdamonds_busy(struct damon_sysfs_kdamond **kdamonds,
2457 		int nr_kdamonds)
2458 {
2459 	int i;
2460 
2461 	for (i = 0; i < nr_kdamonds; i++) {
2462 		if (damon_sysfs_kdamond_running(kdamonds[i]))
2463 			return true;
2464 	}
2465 
2466 	return false;
2467 }
2468 
2469 static int damon_sysfs_kdamonds_add_dirs(struct damon_sysfs_kdamonds *kdamonds,
2470 		int nr_kdamonds)
2471 {
2472 	struct damon_sysfs_kdamond **kdamonds_arr, *kdamond;
2473 	int err, i;
2474 
2475 	if (damon_sysfs_kdamonds_busy(kdamonds->kdamonds_arr, kdamonds->nr))
2476 		return -EBUSY;
2477 
2478 	damon_sysfs_kdamonds_rm_dirs(kdamonds);
2479 	if (!nr_kdamonds)
2480 		return 0;
2481 
2482 	kdamonds_arr = kmalloc_objs(*kdamonds_arr, nr_kdamonds,
2483 				    GFP_KERNEL | __GFP_NOWARN);
2484 	if (!kdamonds_arr)
2485 		return -ENOMEM;
2486 	kdamonds->kdamonds_arr = kdamonds_arr;
2487 
2488 	for (i = 0; i < nr_kdamonds; i++) {
2489 		kdamond = damon_sysfs_kdamond_alloc();
2490 		if (!kdamond) {
2491 			damon_sysfs_kdamonds_rm_dirs(kdamonds);
2492 			return -ENOMEM;
2493 		}
2494 
2495 		err = kobject_init_and_add(&kdamond->kobj,
2496 				&damon_sysfs_kdamond_ktype, &kdamonds->kobj,
2497 				"%d", i);
2498 		if (err)
2499 			goto out;
2500 
2501 		err = damon_sysfs_kdamond_add_dirs(kdamond);
2502 		if (err)
2503 			goto out;
2504 
2505 		kdamonds_arr[i] = kdamond;
2506 		kdamonds->nr++;
2507 	}
2508 	return 0;
2509 
2510 out:
2511 	damon_sysfs_kdamonds_rm_dirs(kdamonds);
2512 	kobject_put(&kdamond->kobj);
2513 	return err;
2514 }
2515 
2516 static ssize_t nr_kdamonds_show(struct kobject *kobj,
2517 		struct kobj_attribute *attr, char *buf)
2518 {
2519 	struct damon_sysfs_kdamonds *kdamonds = container_of(kobj,
2520 			struct damon_sysfs_kdamonds, kobj);
2521 
2522 	return sysfs_emit(buf, "%d\n", kdamonds->nr);
2523 }
2524 
2525 static ssize_t nr_kdamonds_store(struct kobject *kobj,
2526 		struct kobj_attribute *attr, const char *buf, size_t count)
2527 {
2528 	struct damon_sysfs_kdamonds *kdamonds;
2529 	int nr, err;
2530 
2531 	err = kstrtoint(buf, 0, &nr);
2532 	if (err)
2533 		return err;
2534 	if (nr < 0)
2535 		return -EINVAL;
2536 
2537 	kdamonds = container_of(kobj, struct damon_sysfs_kdamonds, kobj);
2538 
2539 	if (!mutex_trylock(&damon_sysfs_lock))
2540 		return -EBUSY;
2541 	err = damon_sysfs_kdamonds_add_dirs(kdamonds, nr);
2542 	mutex_unlock(&damon_sysfs_lock);
2543 	if (err)
2544 		return err;
2545 
2546 	return count;
2547 }
2548 
2549 static void damon_sysfs_kdamonds_release(struct kobject *kobj)
2550 {
2551 	kfree(container_of(kobj, struct damon_sysfs_kdamonds, kobj));
2552 }
2553 
2554 static struct kobj_attribute damon_sysfs_kdamonds_nr_attr =
2555 		__ATTR_RW_MODE(nr_kdamonds, 0600);
2556 
2557 static struct attribute *damon_sysfs_kdamonds_attrs[] = {
2558 	&damon_sysfs_kdamonds_nr_attr.attr,
2559 	NULL,
2560 };
2561 ATTRIBUTE_GROUPS(damon_sysfs_kdamonds);
2562 
2563 static const struct kobj_type damon_sysfs_kdamonds_ktype = {
2564 	.release = damon_sysfs_kdamonds_release,
2565 	.sysfs_ops = &kobj_sysfs_ops,
2566 	.default_groups = damon_sysfs_kdamonds_groups,
2567 };
2568 
2569 /*
2570  * damon user interface directory
2571  */
2572 
2573 struct damon_sysfs_ui_dir {
2574 	struct kobject kobj;
2575 	struct damon_sysfs_kdamonds *kdamonds;
2576 };
2577 
2578 static struct damon_sysfs_ui_dir *damon_sysfs_ui_dir_alloc(void)
2579 {
2580 	return kzalloc_obj(struct damon_sysfs_ui_dir);
2581 }
2582 
2583 static int damon_sysfs_ui_dir_add_dirs(struct damon_sysfs_ui_dir *ui_dir)
2584 {
2585 	struct damon_sysfs_kdamonds *kdamonds;
2586 	int err;
2587 
2588 	kdamonds = damon_sysfs_kdamonds_alloc();
2589 	if (!kdamonds)
2590 		return -ENOMEM;
2591 
2592 	err = kobject_init_and_add(&kdamonds->kobj,
2593 			&damon_sysfs_kdamonds_ktype, &ui_dir->kobj,
2594 			"kdamonds");
2595 	if (err) {
2596 		kobject_put(&kdamonds->kobj);
2597 		return err;
2598 	}
2599 	ui_dir->kdamonds = kdamonds;
2600 	return err;
2601 }
2602 
2603 static void damon_sysfs_ui_dir_release(struct kobject *kobj)
2604 {
2605 	kfree(container_of(kobj, struct damon_sysfs_ui_dir, kobj));
2606 }
2607 
2608 static struct attribute *damon_sysfs_ui_dir_attrs[] = {
2609 	NULL,
2610 };
2611 ATTRIBUTE_GROUPS(damon_sysfs_ui_dir);
2612 
2613 static const struct kobj_type damon_sysfs_ui_dir_ktype = {
2614 	.release = damon_sysfs_ui_dir_release,
2615 	.sysfs_ops = &kobj_sysfs_ops,
2616 	.default_groups = damon_sysfs_ui_dir_groups,
2617 };
2618 
2619 static int __init damon_sysfs_init(void)
2620 {
2621 	struct kobject *damon_sysfs_root;
2622 	struct damon_sysfs_ui_dir *admin;
2623 	int err;
2624 
2625 	damon_sysfs_root = kobject_create_and_add("damon", mm_kobj);
2626 	if (!damon_sysfs_root)
2627 		return -ENOMEM;
2628 
2629 	admin = damon_sysfs_ui_dir_alloc();
2630 	if (!admin) {
2631 		kobject_put(damon_sysfs_root);
2632 		return -ENOMEM;
2633 	}
2634 	err = kobject_init_and_add(&admin->kobj, &damon_sysfs_ui_dir_ktype,
2635 			damon_sysfs_root, "admin");
2636 	if (err)
2637 		goto out;
2638 	err = damon_sysfs_ui_dir_add_dirs(admin);
2639 	if (err)
2640 		goto out;
2641 	return 0;
2642 
2643 out:
2644 	kobject_put(&admin->kobj);
2645 	kobject_put(damon_sysfs_root);
2646 	return err;
2647 }
2648 subsys_initcall(damon_sysfs_init);
2649 
2650 #include "tests/sysfs-kunit.h"
2651