xref: /linux/arch/s390/appldata/appldata_base.c (revision 975ef7ff81bb000af6e6c8e63e81f89f3468dcf7) 
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Base infrastructure for Linux-z/VM Monitor Stream, Stage 1.
4  * Exports appldata_register_ops() and appldata_unregister_ops() for the
5  * data gathering modules.
6  *
7  * Copyright IBM Corp. 2003, 2009
8  *
9  * Author: Gerald Schaefer <gerald.schaefer@de.ibm.com>
10  */
11 
12 #define KMSG_COMPONENT	"appldata"
13 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
14 
15 #include <linux/module.h>
16 #include <linux/sched/stat.h>
17 #include <linux/init.h>
18 #include <linux/slab.h>
19 #include <linux/errno.h>
20 #include <linux/interrupt.h>
21 #include <linux/proc_fs.h>
22 #include <linux/mm.h>
23 #include <linux/swap.h>
24 #include <linux/pagemap.h>
25 #include <linux/sysctl.h>
26 #include <linux/notifier.h>
27 #include <linux/cpu.h>
28 #include <linux/workqueue.h>
29 #include <linux/suspend.h>
30 #include <linux/platform_device.h>
31 #include <asm/appldata.h>
32 #include <asm/vtimer.h>
33 #include <linux/uaccess.h>
34 #include <asm/io.h>
35 #include <asm/smp.h>
36 
37 #include "appldata.h"
38 
39 
40 #define APPLDATA_CPU_INTERVAL	10000		/* default (CPU) time for
41 						   sampling interval in
42 						   milliseconds */
43 
44 #define TOD_MICRO	0x01000			/* nr. of TOD clock units
45 						   for 1 microsecond */
46 
47 static struct platform_device *appldata_pdev;
48 
49 /*
50  * /proc entries (sysctl)
51  */
52 static const char appldata_proc_name[APPLDATA_PROC_NAME_LENGTH] = "appldata";
53 static int appldata_timer_handler(struct ctl_table *ctl, int write,
54 				  void __user *buffer, size_t *lenp, loff_t *ppos);
55 static int appldata_interval_handler(struct ctl_table *ctl, int write,
56 					 void __user *buffer,
57 					 size_t *lenp, loff_t *ppos);
58 
59 static struct ctl_table_header *appldata_sysctl_header;
60 static struct ctl_table appldata_table[] = {
61 	{
62 		.procname	= "timer",
63 		.mode		= S_IRUGO | S_IWUSR,
64 		.proc_handler	= appldata_timer_handler,
65 	},
66 	{
67 		.procname	= "interval",
68 		.mode		= S_IRUGO | S_IWUSR,
69 		.proc_handler	= appldata_interval_handler,
70 	},
71 	{ },
72 };
73 
74 static struct ctl_table appldata_dir_table[] = {
75 	{
76 		.procname	= appldata_proc_name,
77 		.maxlen		= 0,
78 		.mode		= S_IRUGO | S_IXUGO,
79 		.child		= appldata_table,
80 	},
81 	{ },
82 };
83 
84 /*
85  * Timer
86  */
87 static struct vtimer_list appldata_timer;
88 
89 static DEFINE_SPINLOCK(appldata_timer_lock);
90 static int appldata_interval = APPLDATA_CPU_INTERVAL;
91 static int appldata_timer_active;
92 static int appldata_timer_suspended = 0;
93 
94 /*
95  * Work queue
96  */
97 static struct workqueue_struct *appldata_wq;
98 static void appldata_work_fn(struct work_struct *work);
99 static DECLARE_WORK(appldata_work, appldata_work_fn);
100 
101 
102 /*
103  * Ops list
104  */
105 static DEFINE_MUTEX(appldata_ops_mutex);
106 static LIST_HEAD(appldata_ops_list);
107 
108 
109 /*************************** timer, work, DIAG *******************************/
110 /*
111  * appldata_timer_function()
112  *
113  * schedule work and reschedule timer
114  */
115 static void appldata_timer_function(unsigned long data)
116 {
117 	queue_work(appldata_wq, (struct work_struct *) data);
118 }
119 
120 /*
121  * appldata_work_fn()
122  *
123  * call data gathering function for each (active) module
124  */
125 static void appldata_work_fn(struct work_struct *work)
126 {
127 	struct list_head *lh;
128 	struct appldata_ops *ops;
129 
130 	mutex_lock(&appldata_ops_mutex);
131 	list_for_each(lh, &appldata_ops_list) {
132 		ops = list_entry(lh, struct appldata_ops, list);
133 		if (ops->active == 1) {
134 			ops->callback(ops->data);
135 		}
136 	}
137 	mutex_unlock(&appldata_ops_mutex);
138 }
139 
140 /*
141  * appldata_diag()
142  *
143  * prepare parameter list, issue DIAG 0xDC
144  */
145 int appldata_diag(char record_nr, u16 function, unsigned long buffer,
146 			u16 length, char *mod_lvl)
147 {
148 	struct appldata_product_id id = {
149 		.prod_nr    = {0xD3, 0xC9, 0xD5, 0xE4,
150 			       0xE7, 0xD2, 0xD9},	/* "LINUXKR" */
151 		.prod_fn    = 0xD5D3,			/* "NL" */
152 		.version_nr = 0xF2F6,			/* "26" */
153 		.release_nr = 0xF0F1,			/* "01" */
154 	};
155 
156 	id.record_nr = record_nr;
157 	id.mod_lvl = (mod_lvl[0]) << 8 | mod_lvl[1];
158 	return appldata_asm(&id, function, (void *) buffer, length);
159 }
160 /************************ timer, work, DIAG <END> ****************************/
161 
162 
163 /****************************** /proc stuff **********************************/
164 
165 #define APPLDATA_ADD_TIMER	0
166 #define APPLDATA_DEL_TIMER	1
167 #define APPLDATA_MOD_TIMER	2
168 
169 /*
170  * __appldata_vtimer_setup()
171  *
172  * Add, delete or modify virtual timers on all online cpus.
173  * The caller needs to get the appldata_timer_lock spinlock.
174  */
175 static void __appldata_vtimer_setup(int cmd)
176 {
177 	u64 timer_interval = (u64) appldata_interval * 1000 * TOD_MICRO;
178 
179 	switch (cmd) {
180 	case APPLDATA_ADD_TIMER:
181 		if (appldata_timer_active)
182 			break;
183 		appldata_timer.expires = timer_interval;
184 		add_virt_timer_periodic(&appldata_timer);
185 		appldata_timer_active = 1;
186 		break;
187 	case APPLDATA_DEL_TIMER:
188 		del_virt_timer(&appldata_timer);
189 		if (!appldata_timer_active)
190 			break;
191 		appldata_timer_active = 0;
192 		break;
193 	case APPLDATA_MOD_TIMER:
194 		if (!appldata_timer_active)
195 			break;
196 		mod_virt_timer_periodic(&appldata_timer, timer_interval);
197 	}
198 }
199 
200 /*
201  * appldata_timer_handler()
202  *
203  * Start/Stop timer, show status of timer (0 = not active, 1 = active)
204  */
205 static int
206 appldata_timer_handler(struct ctl_table *ctl, int write,
207 			   void __user *buffer, size_t *lenp, loff_t *ppos)
208 {
209 	unsigned int len;
210 	char buf[2];
211 
212 	if (!*lenp || *ppos) {
213 		*lenp = 0;
214 		return 0;
215 	}
216 	if (!write) {
217 		strncpy(buf, appldata_timer_active ? "1\n" : "0\n",
218 			ARRAY_SIZE(buf));
219 		len = strnlen(buf, ARRAY_SIZE(buf));
220 		if (len > *lenp)
221 			len = *lenp;
222 		if (copy_to_user(buffer, buf, len))
223 			return -EFAULT;
224 		goto out;
225 	}
226 	len = *lenp;
227 	if (copy_from_user(buf, buffer, len > sizeof(buf) ? sizeof(buf) : len))
228 		return -EFAULT;
229 	spin_lock(&appldata_timer_lock);
230 	if (buf[0] == '1')
231 		__appldata_vtimer_setup(APPLDATA_ADD_TIMER);
232 	else if (buf[0] == '0')
233 		__appldata_vtimer_setup(APPLDATA_DEL_TIMER);
234 	spin_unlock(&appldata_timer_lock);
235 out:
236 	*lenp = len;
237 	*ppos += len;
238 	return 0;
239 }
240 
241 /*
242  * appldata_interval_handler()
243  *
244  * Set (CPU) timer interval for collection of data (in milliseconds), show
245  * current timer interval.
246  */
247 static int
248 appldata_interval_handler(struct ctl_table *ctl, int write,
249 			   void __user *buffer, size_t *lenp, loff_t *ppos)
250 {
251 	unsigned int len;
252 	int interval;
253 	char buf[16];
254 
255 	if (!*lenp || *ppos) {
256 		*lenp = 0;
257 		return 0;
258 	}
259 	if (!write) {
260 		len = sprintf(buf, "%i\n", appldata_interval);
261 		if (len > *lenp)
262 			len = *lenp;
263 		if (copy_to_user(buffer, buf, len))
264 			return -EFAULT;
265 		goto out;
266 	}
267 	len = *lenp;
268 	if (copy_from_user(buf, buffer, len > sizeof(buf) ? sizeof(buf) : len))
269 		return -EFAULT;
270 	interval = 0;
271 	sscanf(buf, "%i", &interval);
272 	if (interval <= 0)
273 		return -EINVAL;
274 
275 	spin_lock(&appldata_timer_lock);
276 	appldata_interval = interval;
277 	__appldata_vtimer_setup(APPLDATA_MOD_TIMER);
278 	spin_unlock(&appldata_timer_lock);
279 out:
280 	*lenp = len;
281 	*ppos += len;
282 	return 0;
283 }
284 
285 /*
286  * appldata_generic_handler()
287  *
288  * Generic start/stop monitoring and DIAG, show status of
289  * monitoring (0 = not in process, 1 = in process)
290  */
291 static int
292 appldata_generic_handler(struct ctl_table *ctl, int write,
293 			   void __user *buffer, size_t *lenp, loff_t *ppos)
294 {
295 	struct appldata_ops *ops = NULL, *tmp_ops;
296 	unsigned int len;
297 	int rc, found;
298 	char buf[2];
299 	struct list_head *lh;
300 
301 	found = 0;
302 	mutex_lock(&appldata_ops_mutex);
303 	list_for_each(lh, &appldata_ops_list) {
304 		tmp_ops = list_entry(lh, struct appldata_ops, list);
305 		if (&tmp_ops->ctl_table[2] == ctl) {
306 			found = 1;
307 		}
308 	}
309 	if (!found) {
310 		mutex_unlock(&appldata_ops_mutex);
311 		return -ENODEV;
312 	}
313 	ops = ctl->data;
314 	if (!try_module_get(ops->owner)) {	// protect this function
315 		mutex_unlock(&appldata_ops_mutex);
316 		return -ENODEV;
317 	}
318 	mutex_unlock(&appldata_ops_mutex);
319 
320 	if (!*lenp || *ppos) {
321 		*lenp = 0;
322 		module_put(ops->owner);
323 		return 0;
324 	}
325 	if (!write) {
326 		strncpy(buf, ops->active ? "1\n" : "0\n", ARRAY_SIZE(buf));
327 		len = strnlen(buf, ARRAY_SIZE(buf));
328 		if (len > *lenp)
329 			len = *lenp;
330 		if (copy_to_user(buffer, buf, len)) {
331 			module_put(ops->owner);
332 			return -EFAULT;
333 		}
334 		goto out;
335 	}
336 	len = *lenp;
337 	if (copy_from_user(buf, buffer,
338 			   len > sizeof(buf) ? sizeof(buf) : len)) {
339 		module_put(ops->owner);
340 		return -EFAULT;
341 	}
342 
343 	mutex_lock(&appldata_ops_mutex);
344 	if ((buf[0] == '1') && (ops->active == 0)) {
345 		// protect work queue callback
346 		if (!try_module_get(ops->owner)) {
347 			mutex_unlock(&appldata_ops_mutex);
348 			module_put(ops->owner);
349 			return -ENODEV;
350 		}
351 		ops->callback(ops->data);	// init record
352 		rc = appldata_diag(ops->record_nr,
353 					APPLDATA_START_INTERVAL_REC,
354 					(unsigned long) ops->data, ops->size,
355 					ops->mod_lvl);
356 		if (rc != 0) {
357 			pr_err("Starting the data collection for %s "
358 			       "failed with rc=%d\n", ops->name, rc);
359 			module_put(ops->owner);
360 		} else
361 			ops->active = 1;
362 	} else if ((buf[0] == '0') && (ops->active == 1)) {
363 		ops->active = 0;
364 		rc = appldata_diag(ops->record_nr, APPLDATA_STOP_REC,
365 				(unsigned long) ops->data, ops->size,
366 				ops->mod_lvl);
367 		if (rc != 0)
368 			pr_err("Stopping the data collection for %s "
369 			       "failed with rc=%d\n", ops->name, rc);
370 		module_put(ops->owner);
371 	}
372 	mutex_unlock(&appldata_ops_mutex);
373 out:
374 	*lenp = len;
375 	*ppos += len;
376 	module_put(ops->owner);
377 	return 0;
378 }
379 
380 /*************************** /proc stuff <END> *******************************/
381 
382 
383 /************************* module-ops management *****************************/
384 /*
385  * appldata_register_ops()
386  *
387  * update ops list, register /proc/sys entries
388  */
389 int appldata_register_ops(struct appldata_ops *ops)
390 {
391 	if (ops->size > APPLDATA_MAX_REC_SIZE)
392 		return -EINVAL;
393 
394 	ops->ctl_table = kcalloc(4, sizeof(struct ctl_table), GFP_KERNEL);
395 	if (!ops->ctl_table)
396 		return -ENOMEM;
397 
398 	mutex_lock(&appldata_ops_mutex);
399 	list_add(&ops->list, &appldata_ops_list);
400 	mutex_unlock(&appldata_ops_mutex);
401 
402 	ops->ctl_table[0].procname = appldata_proc_name;
403 	ops->ctl_table[0].maxlen   = 0;
404 	ops->ctl_table[0].mode     = S_IRUGO | S_IXUGO;
405 	ops->ctl_table[0].child    = &ops->ctl_table[2];
406 
407 	ops->ctl_table[2].procname = ops->name;
408 	ops->ctl_table[2].mode     = S_IRUGO | S_IWUSR;
409 	ops->ctl_table[2].proc_handler = appldata_generic_handler;
410 	ops->ctl_table[2].data = ops;
411 
412 	ops->sysctl_header = register_sysctl_table(ops->ctl_table);
413 	if (!ops->sysctl_header)
414 		goto out;
415 	return 0;
416 out:
417 	mutex_lock(&appldata_ops_mutex);
418 	list_del(&ops->list);
419 	mutex_unlock(&appldata_ops_mutex);
420 	kfree(ops->ctl_table);
421 	return -ENOMEM;
422 }
423 
424 /*
425  * appldata_unregister_ops()
426  *
427  * update ops list, unregister /proc entries, stop DIAG if necessary
428  */
429 void appldata_unregister_ops(struct appldata_ops *ops)
430 {
431 	mutex_lock(&appldata_ops_mutex);
432 	list_del(&ops->list);
433 	mutex_unlock(&appldata_ops_mutex);
434 	unregister_sysctl_table(ops->sysctl_header);
435 	kfree(ops->ctl_table);
436 }
437 /********************** module-ops management <END> **************************/
438 
439 
440 /**************************** suspend / resume *******************************/
441 static int appldata_freeze(struct device *dev)
442 {
443 	struct appldata_ops *ops;
444 	int rc;
445 	struct list_head *lh;
446 
447 	spin_lock(&appldata_timer_lock);
448 	if (appldata_timer_active) {
449 		__appldata_vtimer_setup(APPLDATA_DEL_TIMER);
450 		appldata_timer_suspended = 1;
451 	}
452 	spin_unlock(&appldata_timer_lock);
453 
454 	mutex_lock(&appldata_ops_mutex);
455 	list_for_each(lh, &appldata_ops_list) {
456 		ops = list_entry(lh, struct appldata_ops, list);
457 		if (ops->active == 1) {
458 			rc = appldata_diag(ops->record_nr, APPLDATA_STOP_REC,
459 					(unsigned long) ops->data, ops->size,
460 					ops->mod_lvl);
461 			if (rc != 0)
462 				pr_err("Stopping the data collection for %s "
463 				       "failed with rc=%d\n", ops->name, rc);
464 		}
465 	}
466 	mutex_unlock(&appldata_ops_mutex);
467 	return 0;
468 }
469 
470 static int appldata_restore(struct device *dev)
471 {
472 	struct appldata_ops *ops;
473 	int rc;
474 	struct list_head *lh;
475 
476 	spin_lock(&appldata_timer_lock);
477 	if (appldata_timer_suspended) {
478 		__appldata_vtimer_setup(APPLDATA_ADD_TIMER);
479 		appldata_timer_suspended = 0;
480 	}
481 	spin_unlock(&appldata_timer_lock);
482 
483 	mutex_lock(&appldata_ops_mutex);
484 	list_for_each(lh, &appldata_ops_list) {
485 		ops = list_entry(lh, struct appldata_ops, list);
486 		if (ops->active == 1) {
487 			ops->callback(ops->data);	// init record
488 			rc = appldata_diag(ops->record_nr,
489 					APPLDATA_START_INTERVAL_REC,
490 					(unsigned long) ops->data, ops->size,
491 					ops->mod_lvl);
492 			if (rc != 0) {
493 				pr_err("Starting the data collection for %s "
494 				       "failed with rc=%d\n", ops->name, rc);
495 			}
496 		}
497 	}
498 	mutex_unlock(&appldata_ops_mutex);
499 	return 0;
500 }
501 
502 static int appldata_thaw(struct device *dev)
503 {
504 	return appldata_restore(dev);
505 }
506 
507 static const struct dev_pm_ops appldata_pm_ops = {
508 	.freeze		= appldata_freeze,
509 	.thaw		= appldata_thaw,
510 	.restore	= appldata_restore,
511 };
512 
513 static struct platform_driver appldata_pdrv = {
514 	.driver = {
515 		.name	= "appldata",
516 		.pm	= &appldata_pm_ops,
517 	},
518 };
519 /************************* suspend / resume <END> ****************************/
520 
521 
522 /******************************* init / exit *********************************/
523 
524 /*
525  * appldata_init()
526  *
527  * init timer, register /proc entries
528  */
529 static int __init appldata_init(void)
530 {
531 	int rc;
532 
533 	init_virt_timer(&appldata_timer);
534 	appldata_timer.function = appldata_timer_function;
535 	appldata_timer.data = (unsigned long) &appldata_work;
536 
537 	rc = platform_driver_register(&appldata_pdrv);
538 	if (rc)
539 		return rc;
540 
541 	appldata_pdev = platform_device_register_simple("appldata", -1, NULL,
542 							0);
543 	if (IS_ERR(appldata_pdev)) {
544 		rc = PTR_ERR(appldata_pdev);
545 		goto out_driver;
546 	}
547 	appldata_wq = alloc_ordered_workqueue("appldata", 0);
548 	if (!appldata_wq) {
549 		rc = -ENOMEM;
550 		goto out_device;
551 	}
552 
553 	appldata_sysctl_header = register_sysctl_table(appldata_dir_table);
554 	return 0;
555 
556 out_device:
557 	platform_device_unregister(appldata_pdev);
558 out_driver:
559 	platform_driver_unregister(&appldata_pdrv);
560 	return rc;
561 }
562 
563 __initcall(appldata_init);
564 
565 /**************************** init / exit <END> ******************************/
566 
567 EXPORT_SYMBOL_GPL(appldata_register_ops);
568 EXPORT_SYMBOL_GPL(appldata_unregister_ops);
569 EXPORT_SYMBOL_GPL(appldata_diag);
570 
571 #ifdef CONFIG_SWAP
572 EXPORT_SYMBOL_GPL(si_swapinfo);
573 #endif
574 EXPORT_SYMBOL_GPL(nr_threads);
575 EXPORT_SYMBOL_GPL(nr_running);
576 EXPORT_SYMBOL_GPL(nr_iowait);
577