xref: /linux/drivers/s390/crypto/ap_bus.c (revision 123760841a2e5977d4e97f86999b3784df58801d)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright IBM Corp. 2006, 2023
4  * Author(s): Cornelia Huck <cornelia.huck@de.ibm.com>
5  *	      Martin Schwidefsky <schwidefsky@de.ibm.com>
6  *	      Ralph Wuerthner <rwuerthn@de.ibm.com>
7  *	      Felix Beck <felix.beck@de.ibm.com>
8  *	      Holger Dengler <hd@linux.vnet.ibm.com>
9  *	      Harald Freudenberger <freude@linux.ibm.com>
10  *
11  * Adjunct processor bus.
12  */
13 
14 #define KMSG_COMPONENT "ap"
15 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
16 
17 #include <linux/kernel_stat.h>
18 #include <linux/moduleparam.h>
19 #include <linux/init.h>
20 #include <linux/delay.h>
21 #include <linux/err.h>
22 #include <linux/freezer.h>
23 #include <linux/interrupt.h>
24 #include <linux/workqueue.h>
25 #include <linux/slab.h>
26 #include <linux/notifier.h>
27 #include <linux/kthread.h>
28 #include <linux/mutex.h>
29 #include <asm/airq.h>
30 #include <asm/tpi.h>
31 #include <linux/atomic.h>
32 #include <asm/isc.h>
33 #include <linux/hrtimer.h>
34 #include <linux/ktime.h>
35 #include <asm/facility.h>
36 #include <linux/crypto.h>
37 #include <linux/mod_devicetable.h>
38 #include <linux/debugfs.h>
39 #include <linux/ctype.h>
40 #include <linux/module.h>
41 #include <asm/uv.h>
42 #include <asm/chsc.h>
43 
44 #include "ap_bus.h"
45 #include "ap_debug.h"
46 
47 MODULE_AUTHOR("IBM Corporation");
48 MODULE_DESCRIPTION("Adjunct Processor Bus driver");
49 MODULE_LICENSE("GPL");
50 
51 int ap_domain_index = -1;	/* Adjunct Processor Domain Index */
52 static DEFINE_SPINLOCK(ap_domain_lock);
53 module_param_named(domain, ap_domain_index, int, 0440);
54 MODULE_PARM_DESC(domain, "domain index for ap devices");
55 EXPORT_SYMBOL(ap_domain_index);
56 
57 static int ap_thread_flag;
58 module_param_named(poll_thread, ap_thread_flag, int, 0440);
59 MODULE_PARM_DESC(poll_thread, "Turn on/off poll thread, default is 0 (off).");
60 
61 static char *apm_str;
62 module_param_named(apmask, apm_str, charp, 0440);
63 MODULE_PARM_DESC(apmask, "AP bus adapter mask.");
64 
65 static char *aqm_str;
66 module_param_named(aqmask, aqm_str, charp, 0440);
67 MODULE_PARM_DESC(aqmask, "AP bus domain mask.");
68 
69 static int ap_useirq = 1;
70 module_param_named(useirq, ap_useirq, int, 0440);
71 MODULE_PARM_DESC(useirq, "Use interrupt if available, default is 1 (on).");
72 
73 atomic_t ap_max_msg_size = ATOMIC_INIT(AP_DEFAULT_MAX_MSG_SIZE);
74 EXPORT_SYMBOL(ap_max_msg_size);
75 
76 static struct device *ap_root_device;
77 
78 /* Hashtable of all queue devices on the AP bus */
79 DEFINE_HASHTABLE(ap_queues, 8);
80 /* lock used for the ap_queues hashtable */
81 DEFINE_SPINLOCK(ap_queues_lock);
82 
83 /* Default permissions (ioctl, card and domain masking) */
84 struct ap_perms ap_perms;
85 EXPORT_SYMBOL(ap_perms);
86 DEFINE_MUTEX(ap_perms_mutex);
87 EXPORT_SYMBOL(ap_perms_mutex);
88 
89 /* # of bindings complete since init */
90 static atomic64_t ap_bindings_complete_count = ATOMIC64_INIT(0);
91 
92 /* completion for APQN bindings complete */
93 static DECLARE_COMPLETION(ap_apqn_bindings_complete);
94 
95 static struct ap_config_info qci[2];
96 static struct ap_config_info *const ap_qci_info = &qci[0];
97 static struct ap_config_info *const ap_qci_info_old = &qci[1];
98 
99 /*
100  * AP bus related debug feature things.
101  */
102 debug_info_t *ap_dbf_info;
103 
104 /*
105  * AP bus rescan related things.
106  */
107 static bool ap_scan_bus(void);
108 static bool ap_scan_bus_result; /* result of last ap_scan_bus() */
109 static DEFINE_MUTEX(ap_scan_bus_mutex); /* mutex ap_scan_bus() invocations */
110 static atomic64_t ap_scan_bus_count; /* counter ap_scan_bus() invocations */
111 static int ap_scan_bus_time = AP_CONFIG_TIME;
112 static struct timer_list ap_scan_bus_timer;
113 static void ap_scan_bus_wq_callback(struct work_struct *);
114 static DECLARE_WORK(ap_scan_bus_work, ap_scan_bus_wq_callback);
115 
116 /*
117  * Tasklet & timer for AP request polling and interrupts
118  */
119 static void ap_tasklet_fn(unsigned long);
120 static DECLARE_TASKLET_OLD(ap_tasklet, ap_tasklet_fn);
121 static DECLARE_WAIT_QUEUE_HEAD(ap_poll_wait);
122 static struct task_struct *ap_poll_kthread;
123 static DEFINE_MUTEX(ap_poll_thread_mutex);
124 static DEFINE_SPINLOCK(ap_poll_timer_lock);
125 static struct hrtimer ap_poll_timer;
126 /*
127  * In LPAR poll with 4kHz frequency. Poll every 250000 nanoseconds.
128  * If z/VM change to 1500000 nanoseconds to adjust to z/VM polling.
129  */
130 static unsigned long poll_high_timeout = 250000UL;
131 
132 /*
133  * Some state machine states only require a low frequency polling.
134  * We use 25 Hz frequency for these.
135  */
136 static unsigned long poll_low_timeout = 40000000UL;
137 
138 /* Maximum domain id, if not given via qci */
139 static int ap_max_domain_id = 15;
140 /* Maximum adapter id, if not given via qci */
141 static int ap_max_adapter_id = 63;
142 
143 static const struct bus_type ap_bus_type;
144 
145 /* Adapter interrupt definitions */
146 static void ap_interrupt_handler(struct airq_struct *airq,
147 				 struct tpi_info *tpi_info);
148 
149 static bool ap_irq_flag;
150 
151 static struct airq_struct ap_airq = {
152 	.handler = ap_interrupt_handler,
153 	.isc = AP_ISC,
154 };
155 
156 /**
157  * ap_airq_ptr() - Get the address of the adapter interrupt indicator
158  *
159  * Returns the address of the local-summary-indicator of the adapter
160  * interrupt handler for AP, or NULL if adapter interrupts are not
161  * available.
162  */
163 void *ap_airq_ptr(void)
164 {
165 	if (ap_irq_flag)
166 		return ap_airq.lsi_ptr;
167 	return NULL;
168 }
169 
170 /**
171  * ap_interrupts_available(): Test if AP interrupts are available.
172  *
173  * Returns 1 if AP interrupts are available.
174  */
175 static int ap_interrupts_available(void)
176 {
177 	return test_facility(65);
178 }
179 
180 /**
181  * ap_qci_available(): Test if AP configuration
182  * information can be queried via QCI subfunction.
183  *
184  * Returns 1 if subfunction PQAP(QCI) is available.
185  */
186 static int ap_qci_available(void)
187 {
188 	return test_facility(12);
189 }
190 
191 /**
192  * ap_apft_available(): Test if AP facilities test (APFT)
193  * facility is available.
194  *
195  * Returns 1 if APFT is available.
196  */
197 static int ap_apft_available(void)
198 {
199 	return test_facility(15);
200 }
201 
202 /*
203  * ap_qact_available(): Test if the PQAP(QACT) subfunction is available.
204  *
205  * Returns 1 if the QACT subfunction is available.
206  */
207 static inline int ap_qact_available(void)
208 {
209 	return ap_qci_info->qact;
210 }
211 
212 /*
213  * ap_sb_available(): Test if the AP secure binding facility is available.
214  *
215  * Returns 1 if secure binding facility is available.
216  */
217 int ap_sb_available(void)
218 {
219 	return ap_qci_info->apsb;
220 }
221 
222 /*
223  * ap_is_se_guest(): Check for SE guest with AP pass-through support.
224  */
225 bool ap_is_se_guest(void)
226 {
227 	return is_prot_virt_guest() && ap_sb_available();
228 }
229 EXPORT_SYMBOL(ap_is_se_guest);
230 
231 /**
232  * ap_init_qci_info(): Allocate and query qci config info.
233  * Does also update the static variables ap_max_domain_id
234  * and ap_max_adapter_id if this info is available.
235  */
236 static void __init ap_init_qci_info(void)
237 {
238 	if (!ap_qci_available() ||
239 	    ap_qci(ap_qci_info)) {
240 		AP_DBF_INFO("%s QCI not supported\n", __func__);
241 		return;
242 	}
243 	memcpy(ap_qci_info_old, ap_qci_info, sizeof(*ap_qci_info));
244 	AP_DBF_INFO("%s successful fetched initial qci info\n", __func__);
245 
246 	if (ap_qci_info->apxa) {
247 		if (ap_qci_info->na) {
248 			ap_max_adapter_id = ap_qci_info->na;
249 			AP_DBF_INFO("%s new ap_max_adapter_id is %d\n",
250 				    __func__, ap_max_adapter_id);
251 		}
252 		if (ap_qci_info->nd) {
253 			ap_max_domain_id = ap_qci_info->nd;
254 			AP_DBF_INFO("%s new ap_max_domain_id is %d\n",
255 				    __func__, ap_max_domain_id);
256 		}
257 	}
258 }
259 
260 /*
261  * ap_test_config(): helper function to extract the nrth bit
262  *		     within the unsigned int array field.
263  */
264 static inline int ap_test_config(unsigned int *field, unsigned int nr)
265 {
266 	return ap_test_bit((field + (nr >> 5)), (nr & 0x1f));
267 }
268 
269 /*
270  * ap_test_config_card_id(): Test, whether an AP card ID is configured.
271  *
272  * Returns 0 if the card is not configured
273  *	   1 if the card is configured or
274  *	     if the configuration information is not available
275  */
276 static inline int ap_test_config_card_id(unsigned int id)
277 {
278 	if (id > ap_max_adapter_id)
279 		return 0;
280 	if (ap_qci_info->flags)
281 		return ap_test_config(ap_qci_info->apm, id);
282 	return 1;
283 }
284 
285 /*
286  * ap_test_config_usage_domain(): Test, whether an AP usage domain
287  * is configured.
288  *
289  * Returns 0 if the usage domain is not configured
290  *	   1 if the usage domain is configured or
291  *	     if the configuration information is not available
292  */
293 int ap_test_config_usage_domain(unsigned int domain)
294 {
295 	if (domain > ap_max_domain_id)
296 		return 0;
297 	if (ap_qci_info->flags)
298 		return ap_test_config(ap_qci_info->aqm, domain);
299 	return 1;
300 }
301 EXPORT_SYMBOL(ap_test_config_usage_domain);
302 
303 /*
304  * ap_test_config_ctrl_domain(): Test, whether an AP control domain
305  * is configured.
306  * @domain AP control domain ID
307  *
308  * Returns 1 if the control domain is configured
309  *	   0 in all other cases
310  */
311 int ap_test_config_ctrl_domain(unsigned int domain)
312 {
313 	if (!ap_qci_info || domain > ap_max_domain_id)
314 		return 0;
315 	return ap_test_config(ap_qci_info->adm, domain);
316 }
317 EXPORT_SYMBOL(ap_test_config_ctrl_domain);
318 
319 /*
320  * ap_queue_info(): Check and get AP queue info.
321  * Returns: 1 if APQN exists and info is filled,
322  *	    0 if APQN seems to exist but there is no info
323  *	      available (eg. caused by an asynch pending error)
324  *	   -1 invalid APQN, TAPQ error or AP queue status which
325  *	      indicates there is no APQN.
326  */
327 static int ap_queue_info(ap_qid_t qid, struct ap_tapq_hwinfo *hwinfo,
328 			 bool *decfg, bool *cstop)
329 {
330 	struct ap_queue_status status;
331 
332 	hwinfo->value = 0;
333 
334 	/* make sure we don't run into a specifiation exception */
335 	if (AP_QID_CARD(qid) > ap_max_adapter_id ||
336 	    AP_QID_QUEUE(qid) > ap_max_domain_id)
337 		return -1;
338 
339 	/* call TAPQ on this APQN */
340 	status = ap_test_queue(qid, ap_apft_available(), hwinfo);
341 
342 	switch (status.response_code) {
343 	case AP_RESPONSE_NORMAL:
344 	case AP_RESPONSE_RESET_IN_PROGRESS:
345 	case AP_RESPONSE_DECONFIGURED:
346 	case AP_RESPONSE_CHECKSTOPPED:
347 	case AP_RESPONSE_BUSY:
348 		/* For all these RCs the tapq info should be available */
349 		break;
350 	default:
351 		/* On a pending async error the info should be available */
352 		if (!status.async)
353 			return -1;
354 		break;
355 	}
356 
357 	/* There should be at least one of the mode bits set */
358 	if (WARN_ON_ONCE(!hwinfo->value))
359 		return 0;
360 
361 	*decfg = status.response_code == AP_RESPONSE_DECONFIGURED;
362 	*cstop = status.response_code == AP_RESPONSE_CHECKSTOPPED;
363 
364 	return 1;
365 }
366 
367 void ap_wait(enum ap_sm_wait wait)
368 {
369 	ktime_t hr_time;
370 
371 	switch (wait) {
372 	case AP_SM_WAIT_AGAIN:
373 	case AP_SM_WAIT_INTERRUPT:
374 		if (ap_irq_flag)
375 			break;
376 		if (ap_poll_kthread) {
377 			wake_up(&ap_poll_wait);
378 			break;
379 		}
380 		fallthrough;
381 	case AP_SM_WAIT_LOW_TIMEOUT:
382 	case AP_SM_WAIT_HIGH_TIMEOUT:
383 		spin_lock_bh(&ap_poll_timer_lock);
384 		if (!hrtimer_is_queued(&ap_poll_timer)) {
385 			hr_time =
386 				wait == AP_SM_WAIT_LOW_TIMEOUT ?
387 				poll_low_timeout : poll_high_timeout;
388 			hrtimer_forward_now(&ap_poll_timer, hr_time);
389 			hrtimer_restart(&ap_poll_timer);
390 		}
391 		spin_unlock_bh(&ap_poll_timer_lock);
392 		break;
393 	case AP_SM_WAIT_NONE:
394 	default:
395 		break;
396 	}
397 }
398 
399 /**
400  * ap_request_timeout(): Handling of request timeouts
401  * @t: timer making this callback
402  *
403  * Handles request timeouts.
404  */
405 void ap_request_timeout(struct timer_list *t)
406 {
407 	struct ap_queue *aq = from_timer(aq, t, timeout);
408 
409 	spin_lock_bh(&aq->lock);
410 	ap_wait(ap_sm_event(aq, AP_SM_EVENT_TIMEOUT));
411 	spin_unlock_bh(&aq->lock);
412 }
413 
414 /**
415  * ap_poll_timeout(): AP receive polling for finished AP requests.
416  * @unused: Unused pointer.
417  *
418  * Schedules the AP tasklet using a high resolution timer.
419  */
420 static enum hrtimer_restart ap_poll_timeout(struct hrtimer *unused)
421 {
422 	tasklet_schedule(&ap_tasklet);
423 	return HRTIMER_NORESTART;
424 }
425 
426 /**
427  * ap_interrupt_handler() - Schedule ap_tasklet on interrupt
428  * @airq: pointer to adapter interrupt descriptor
429  * @tpi_info: ignored
430  */
431 static void ap_interrupt_handler(struct airq_struct *airq,
432 				 struct tpi_info *tpi_info)
433 {
434 	inc_irq_stat(IRQIO_APB);
435 	tasklet_schedule(&ap_tasklet);
436 }
437 
438 /**
439  * ap_tasklet_fn(): Tasklet to poll all AP devices.
440  * @dummy: Unused variable
441  *
442  * Poll all AP devices on the bus.
443  */
444 static void ap_tasklet_fn(unsigned long dummy)
445 {
446 	int bkt;
447 	struct ap_queue *aq;
448 	enum ap_sm_wait wait = AP_SM_WAIT_NONE;
449 
450 	/* Reset the indicator if interrupts are used. Thus new interrupts can
451 	 * be received. Doing it in the beginning of the tasklet is therefore
452 	 * important that no requests on any AP get lost.
453 	 */
454 	if (ap_irq_flag)
455 		xchg(ap_airq.lsi_ptr, 0);
456 
457 	spin_lock_bh(&ap_queues_lock);
458 	hash_for_each(ap_queues, bkt, aq, hnode) {
459 		spin_lock_bh(&aq->lock);
460 		wait = min(wait, ap_sm_event_loop(aq, AP_SM_EVENT_POLL));
461 		spin_unlock_bh(&aq->lock);
462 	}
463 	spin_unlock_bh(&ap_queues_lock);
464 
465 	ap_wait(wait);
466 }
467 
468 static int ap_pending_requests(void)
469 {
470 	int bkt;
471 	struct ap_queue *aq;
472 
473 	spin_lock_bh(&ap_queues_lock);
474 	hash_for_each(ap_queues, bkt, aq, hnode) {
475 		if (aq->queue_count == 0)
476 			continue;
477 		spin_unlock_bh(&ap_queues_lock);
478 		return 1;
479 	}
480 	spin_unlock_bh(&ap_queues_lock);
481 	return 0;
482 }
483 
484 /**
485  * ap_poll_thread(): Thread that polls for finished requests.
486  * @data: Unused pointer
487  *
488  * AP bus poll thread. The purpose of this thread is to poll for
489  * finished requests in a loop if there is a "free" cpu - that is
490  * a cpu that doesn't have anything better to do. The polling stops
491  * as soon as there is another task or if all messages have been
492  * delivered.
493  */
494 static int ap_poll_thread(void *data)
495 {
496 	DECLARE_WAITQUEUE(wait, current);
497 
498 	set_user_nice(current, MAX_NICE);
499 	set_freezable();
500 	while (!kthread_should_stop()) {
501 		add_wait_queue(&ap_poll_wait, &wait);
502 		set_current_state(TASK_INTERRUPTIBLE);
503 		if (!ap_pending_requests()) {
504 			schedule();
505 			try_to_freeze();
506 		}
507 		set_current_state(TASK_RUNNING);
508 		remove_wait_queue(&ap_poll_wait, &wait);
509 		if (need_resched()) {
510 			schedule();
511 			try_to_freeze();
512 			continue;
513 		}
514 		ap_tasklet_fn(0);
515 	}
516 
517 	return 0;
518 }
519 
520 static int ap_poll_thread_start(void)
521 {
522 	int rc;
523 
524 	if (ap_irq_flag || ap_poll_kthread)
525 		return 0;
526 	mutex_lock(&ap_poll_thread_mutex);
527 	ap_poll_kthread = kthread_run(ap_poll_thread, NULL, "appoll");
528 	rc = PTR_ERR_OR_ZERO(ap_poll_kthread);
529 	if (rc)
530 		ap_poll_kthread = NULL;
531 	mutex_unlock(&ap_poll_thread_mutex);
532 	return rc;
533 }
534 
535 static void ap_poll_thread_stop(void)
536 {
537 	if (!ap_poll_kthread)
538 		return;
539 	mutex_lock(&ap_poll_thread_mutex);
540 	kthread_stop(ap_poll_kthread);
541 	ap_poll_kthread = NULL;
542 	mutex_unlock(&ap_poll_thread_mutex);
543 }
544 
545 #define is_card_dev(x) ((x)->parent == ap_root_device)
546 #define is_queue_dev(x) ((x)->parent != ap_root_device)
547 
548 /**
549  * ap_bus_match()
550  * @dev: Pointer to device
551  * @drv: Pointer to device_driver
552  *
553  * AP bus driver registration/unregistration.
554  */
555 static int ap_bus_match(struct device *dev, struct device_driver *drv)
556 {
557 	struct ap_driver *ap_drv = to_ap_drv(drv);
558 	struct ap_device_id *id;
559 
560 	/*
561 	 * Compare device type of the device with the list of
562 	 * supported types of the device_driver.
563 	 */
564 	for (id = ap_drv->ids; id->match_flags; id++) {
565 		if (is_card_dev(dev) &&
566 		    id->match_flags & AP_DEVICE_ID_MATCH_CARD_TYPE &&
567 		    id->dev_type == to_ap_dev(dev)->device_type)
568 			return 1;
569 		if (is_queue_dev(dev) &&
570 		    id->match_flags & AP_DEVICE_ID_MATCH_QUEUE_TYPE &&
571 		    id->dev_type == to_ap_dev(dev)->device_type)
572 			return 1;
573 	}
574 	return 0;
575 }
576 
577 /**
578  * ap_uevent(): Uevent function for AP devices.
579  * @dev: Pointer to device
580  * @env: Pointer to kobj_uevent_env
581  *
582  * It sets up a single environment variable DEV_TYPE which contains the
583  * hardware device type.
584  */
585 static int ap_uevent(const struct device *dev, struct kobj_uevent_env *env)
586 {
587 	int rc = 0;
588 	const struct ap_device *ap_dev = to_ap_dev(dev);
589 
590 	/* Uevents from ap bus core don't need extensions to the env */
591 	if (dev == ap_root_device)
592 		return 0;
593 
594 	if (is_card_dev(dev)) {
595 		struct ap_card *ac = to_ap_card(&ap_dev->device);
596 
597 		/* Set up DEV_TYPE environment variable. */
598 		rc = add_uevent_var(env, "DEV_TYPE=%04X", ap_dev->device_type);
599 		if (rc)
600 			return rc;
601 		/* Add MODALIAS= */
602 		rc = add_uevent_var(env, "MODALIAS=ap:t%02X", ap_dev->device_type);
603 		if (rc)
604 			return rc;
605 
606 		/* Add MODE=<accel|cca|ep11> */
607 		if (ac->hwinfo.accel)
608 			rc = add_uevent_var(env, "MODE=accel");
609 		else if (ac->hwinfo.cca)
610 			rc = add_uevent_var(env, "MODE=cca");
611 		else if (ac->hwinfo.ep11)
612 			rc = add_uevent_var(env, "MODE=ep11");
613 		if (rc)
614 			return rc;
615 	} else {
616 		struct ap_queue *aq = to_ap_queue(&ap_dev->device);
617 
618 		/* Add MODE=<accel|cca|ep11> */
619 		if (aq->card->hwinfo.accel)
620 			rc = add_uevent_var(env, "MODE=accel");
621 		else if (aq->card->hwinfo.cca)
622 			rc = add_uevent_var(env, "MODE=cca");
623 		else if (aq->card->hwinfo.ep11)
624 			rc = add_uevent_var(env, "MODE=ep11");
625 		if (rc)
626 			return rc;
627 	}
628 
629 	return 0;
630 }
631 
632 static void ap_send_init_scan_done_uevent(void)
633 {
634 	char *envp[] = { "INITSCAN=done", NULL };
635 
636 	kobject_uevent_env(&ap_root_device->kobj, KOBJ_CHANGE, envp);
637 }
638 
639 static void ap_send_bindings_complete_uevent(void)
640 {
641 	char buf[32];
642 	char *envp[] = { "BINDINGS=complete", buf, NULL };
643 
644 	snprintf(buf, sizeof(buf), "COMPLETECOUNT=%llu",
645 		 atomic64_inc_return(&ap_bindings_complete_count));
646 	kobject_uevent_env(&ap_root_device->kobj, KOBJ_CHANGE, envp);
647 }
648 
649 void ap_send_config_uevent(struct ap_device *ap_dev, bool cfg)
650 {
651 	char buf[16];
652 	char *envp[] = { buf, NULL };
653 
654 	snprintf(buf, sizeof(buf), "CONFIG=%d", cfg ? 1 : 0);
655 
656 	kobject_uevent_env(&ap_dev->device.kobj, KOBJ_CHANGE, envp);
657 }
658 EXPORT_SYMBOL(ap_send_config_uevent);
659 
660 void ap_send_online_uevent(struct ap_device *ap_dev, int online)
661 {
662 	char buf[16];
663 	char *envp[] = { buf, NULL };
664 
665 	snprintf(buf, sizeof(buf), "ONLINE=%d", online ? 1 : 0);
666 
667 	kobject_uevent_env(&ap_dev->device.kobj, KOBJ_CHANGE, envp);
668 }
669 EXPORT_SYMBOL(ap_send_online_uevent);
670 
671 static void ap_send_mask_changed_uevent(unsigned long *newapm,
672 					unsigned long *newaqm)
673 {
674 	char buf[100];
675 	char *envp[] = { buf, NULL };
676 
677 	if (newapm)
678 		snprintf(buf, sizeof(buf),
679 			 "APMASK=0x%016lx%016lx%016lx%016lx\n",
680 			 newapm[0], newapm[1], newapm[2], newapm[3]);
681 	else
682 		snprintf(buf, sizeof(buf),
683 			 "AQMASK=0x%016lx%016lx%016lx%016lx\n",
684 			 newaqm[0], newaqm[1], newaqm[2], newaqm[3]);
685 
686 	kobject_uevent_env(&ap_root_device->kobj, KOBJ_CHANGE, envp);
687 }
688 
689 /*
690  * calc # of bound APQNs
691  */
692 
693 struct __ap_calc_ctrs {
694 	unsigned int apqns;
695 	unsigned int bound;
696 };
697 
698 static int __ap_calc_helper(struct device *dev, void *arg)
699 {
700 	struct __ap_calc_ctrs *pctrs = (struct __ap_calc_ctrs *)arg;
701 
702 	if (is_queue_dev(dev)) {
703 		pctrs->apqns++;
704 		if (dev->driver)
705 			pctrs->bound++;
706 	}
707 
708 	return 0;
709 }
710 
711 static void ap_calc_bound_apqns(unsigned int *apqns, unsigned int *bound)
712 {
713 	struct __ap_calc_ctrs ctrs;
714 
715 	memset(&ctrs, 0, sizeof(ctrs));
716 	bus_for_each_dev(&ap_bus_type, NULL, (void *)&ctrs, __ap_calc_helper);
717 
718 	*apqns = ctrs.apqns;
719 	*bound = ctrs.bound;
720 }
721 
722 /*
723  * After ap bus scan do check if all existing APQNs are
724  * bound to device drivers.
725  */
726 static void ap_check_bindings_complete(void)
727 {
728 	unsigned int apqns, bound;
729 
730 	if (atomic64_read(&ap_scan_bus_count) >= 1) {
731 		ap_calc_bound_apqns(&apqns, &bound);
732 		if (bound == apqns) {
733 			if (!completion_done(&ap_apqn_bindings_complete)) {
734 				complete_all(&ap_apqn_bindings_complete);
735 				pr_debug("%s all apqn bindings complete\n", __func__);
736 			}
737 			ap_send_bindings_complete_uevent();
738 		}
739 	}
740 }
741 
742 /*
743  * Interface to wait for the AP bus to have done one initial ap bus
744  * scan and all detected APQNs have been bound to device drivers.
745  * If these both conditions are not fulfilled, this function blocks
746  * on a condition with wait_for_completion_interruptible_timeout().
747  * If these both conditions are fulfilled (before the timeout hits)
748  * the return value is 0. If the timeout (in jiffies) hits instead
749  * -ETIME is returned. On failures negative return values are
750  * returned to the caller.
751  */
752 int ap_wait_apqn_bindings_complete(unsigned long timeout)
753 {
754 	int rc = 0;
755 	long l;
756 
757 	if (completion_done(&ap_apqn_bindings_complete))
758 		return 0;
759 
760 	if (timeout)
761 		l = wait_for_completion_interruptible_timeout(
762 			&ap_apqn_bindings_complete, timeout);
763 	else
764 		l = wait_for_completion_interruptible(
765 			&ap_apqn_bindings_complete);
766 	if (l < 0)
767 		rc = l == -ERESTARTSYS ? -EINTR : l;
768 	else if (l == 0 && timeout)
769 		rc = -ETIME;
770 
771 	pr_debug("%s rc=%d\n", __func__, rc);
772 	return rc;
773 }
774 EXPORT_SYMBOL(ap_wait_apqn_bindings_complete);
775 
776 static int __ap_queue_devices_with_id_unregister(struct device *dev, void *data)
777 {
778 	if (is_queue_dev(dev) &&
779 	    AP_QID_CARD(to_ap_queue(dev)->qid) == (int)(long)data)
780 		device_unregister(dev);
781 	return 0;
782 }
783 
784 static int __ap_revise_reserved(struct device *dev, void *dummy)
785 {
786 	int rc, card, queue, devres, drvres;
787 
788 	if (is_queue_dev(dev)) {
789 		card = AP_QID_CARD(to_ap_queue(dev)->qid);
790 		queue = AP_QID_QUEUE(to_ap_queue(dev)->qid);
791 		mutex_lock(&ap_perms_mutex);
792 		devres = test_bit_inv(card, ap_perms.apm) &&
793 			test_bit_inv(queue, ap_perms.aqm);
794 		mutex_unlock(&ap_perms_mutex);
795 		drvres = to_ap_drv(dev->driver)->flags
796 			& AP_DRIVER_FLAG_DEFAULT;
797 		if (!!devres != !!drvres) {
798 			pr_debug("%s reprobing queue=%02x.%04x\n",
799 				 __func__, card, queue);
800 			rc = device_reprobe(dev);
801 			if (rc)
802 				AP_DBF_WARN("%s reprobing queue=%02x.%04x failed\n",
803 					    __func__, card, queue);
804 		}
805 	}
806 
807 	return 0;
808 }
809 
810 static void ap_bus_revise_bindings(void)
811 {
812 	bus_for_each_dev(&ap_bus_type, NULL, NULL, __ap_revise_reserved);
813 }
814 
815 /**
816  * ap_owned_by_def_drv: indicates whether an AP adapter is reserved for the
817  *			default host driver or not.
818  * @card: the APID of the adapter card to check
819  * @queue: the APQI of the queue to check
820  *
821  * Note: the ap_perms_mutex must be locked by the caller of this function.
822  *
823  * Return: an int specifying whether the AP adapter is reserved for the host (1)
824  *	   or not (0).
825  */
826 int ap_owned_by_def_drv(int card, int queue)
827 {
828 	int rc = 0;
829 
830 	if (card < 0 || card >= AP_DEVICES || queue < 0 || queue >= AP_DOMAINS)
831 		return -EINVAL;
832 
833 	if (test_bit_inv(card, ap_perms.apm) &&
834 	    test_bit_inv(queue, ap_perms.aqm))
835 		rc = 1;
836 
837 	return rc;
838 }
839 EXPORT_SYMBOL(ap_owned_by_def_drv);
840 
841 /**
842  * ap_apqn_in_matrix_owned_by_def_drv: indicates whether every APQN contained in
843  *				       a set is reserved for the host drivers
844  *				       or not.
845  * @apm: a bitmap specifying a set of APIDs comprising the APQNs to check
846  * @aqm: a bitmap specifying a set of APQIs comprising the APQNs to check
847  *
848  * Note: the ap_perms_mutex must be locked by the caller of this function.
849  *
850  * Return: an int specifying whether each APQN is reserved for the host (1) or
851  *	   not (0)
852  */
853 int ap_apqn_in_matrix_owned_by_def_drv(unsigned long *apm,
854 				       unsigned long *aqm)
855 {
856 	int card, queue, rc = 0;
857 
858 	for (card = 0; !rc && card < AP_DEVICES; card++)
859 		if (test_bit_inv(card, apm) &&
860 		    test_bit_inv(card, ap_perms.apm))
861 			for (queue = 0; !rc && queue < AP_DOMAINS; queue++)
862 				if (test_bit_inv(queue, aqm) &&
863 				    test_bit_inv(queue, ap_perms.aqm))
864 					rc = 1;
865 
866 	return rc;
867 }
868 EXPORT_SYMBOL(ap_apqn_in_matrix_owned_by_def_drv);
869 
870 static int ap_device_probe(struct device *dev)
871 {
872 	struct ap_device *ap_dev = to_ap_dev(dev);
873 	struct ap_driver *ap_drv = to_ap_drv(dev->driver);
874 	int card, queue, devres, drvres, rc = -ENODEV;
875 
876 	if (!get_device(dev))
877 		return rc;
878 
879 	if (is_queue_dev(dev)) {
880 		/*
881 		 * If the apqn is marked as reserved/used by ap bus and
882 		 * default drivers, only probe with drivers with the default
883 		 * flag set. If it is not marked, only probe with drivers
884 		 * with the default flag not set.
885 		 */
886 		card = AP_QID_CARD(to_ap_queue(dev)->qid);
887 		queue = AP_QID_QUEUE(to_ap_queue(dev)->qid);
888 		mutex_lock(&ap_perms_mutex);
889 		devres = test_bit_inv(card, ap_perms.apm) &&
890 			test_bit_inv(queue, ap_perms.aqm);
891 		mutex_unlock(&ap_perms_mutex);
892 		drvres = ap_drv->flags & AP_DRIVER_FLAG_DEFAULT;
893 		if (!!devres != !!drvres)
894 			goto out;
895 	}
896 
897 	/* Add queue/card to list of active queues/cards */
898 	spin_lock_bh(&ap_queues_lock);
899 	if (is_queue_dev(dev))
900 		hash_add(ap_queues, &to_ap_queue(dev)->hnode,
901 			 to_ap_queue(dev)->qid);
902 	spin_unlock_bh(&ap_queues_lock);
903 
904 	rc = ap_drv->probe ? ap_drv->probe(ap_dev) : -ENODEV;
905 
906 	if (rc) {
907 		spin_lock_bh(&ap_queues_lock);
908 		if (is_queue_dev(dev))
909 			hash_del(&to_ap_queue(dev)->hnode);
910 		spin_unlock_bh(&ap_queues_lock);
911 	}
912 
913 out:
914 	if (rc)
915 		put_device(dev);
916 	return rc;
917 }
918 
919 static void ap_device_remove(struct device *dev)
920 {
921 	struct ap_device *ap_dev = to_ap_dev(dev);
922 	struct ap_driver *ap_drv = to_ap_drv(dev->driver);
923 
924 	/* prepare ap queue device removal */
925 	if (is_queue_dev(dev))
926 		ap_queue_prepare_remove(to_ap_queue(dev));
927 
928 	/* driver's chance to clean up gracefully */
929 	if (ap_drv->remove)
930 		ap_drv->remove(ap_dev);
931 
932 	/* now do the ap queue device remove */
933 	if (is_queue_dev(dev))
934 		ap_queue_remove(to_ap_queue(dev));
935 
936 	/* Remove queue/card from list of active queues/cards */
937 	spin_lock_bh(&ap_queues_lock);
938 	if (is_queue_dev(dev))
939 		hash_del(&to_ap_queue(dev)->hnode);
940 	spin_unlock_bh(&ap_queues_lock);
941 
942 	put_device(dev);
943 }
944 
945 struct ap_queue *ap_get_qdev(ap_qid_t qid)
946 {
947 	int bkt;
948 	struct ap_queue *aq;
949 
950 	spin_lock_bh(&ap_queues_lock);
951 	hash_for_each(ap_queues, bkt, aq, hnode) {
952 		if (aq->qid == qid) {
953 			get_device(&aq->ap_dev.device);
954 			spin_unlock_bh(&ap_queues_lock);
955 			return aq;
956 		}
957 	}
958 	spin_unlock_bh(&ap_queues_lock);
959 
960 	return NULL;
961 }
962 EXPORT_SYMBOL(ap_get_qdev);
963 
964 int ap_driver_register(struct ap_driver *ap_drv, struct module *owner,
965 		       char *name)
966 {
967 	struct device_driver *drv = &ap_drv->driver;
968 
969 	drv->bus = &ap_bus_type;
970 	drv->owner = owner;
971 	drv->name = name;
972 	return driver_register(drv);
973 }
974 EXPORT_SYMBOL(ap_driver_register);
975 
976 void ap_driver_unregister(struct ap_driver *ap_drv)
977 {
978 	driver_unregister(&ap_drv->driver);
979 }
980 EXPORT_SYMBOL(ap_driver_unregister);
981 
982 /*
983  * Enforce a synchronous AP bus rescan.
984  * Returns true if the bus scan finds a change in the AP configuration
985  * and AP devices have been added or deleted when this function returns.
986  */
987 bool ap_bus_force_rescan(void)
988 {
989 	unsigned long scan_counter = atomic64_read(&ap_scan_bus_count);
990 	bool rc = false;
991 
992 	pr_debug(">%s scan counter=%lu\n", __func__, scan_counter);
993 
994 	/* Only trigger AP bus scans after the initial scan is done */
995 	if (scan_counter <= 0)
996 		goto out;
997 
998 	/* Try to acquire the AP scan bus mutex */
999 	if (mutex_trylock(&ap_scan_bus_mutex)) {
1000 		/* mutex acquired, run the AP bus scan */
1001 		ap_scan_bus_result = ap_scan_bus();
1002 		rc = ap_scan_bus_result;
1003 		mutex_unlock(&ap_scan_bus_mutex);
1004 		goto out;
1005 	}
1006 
1007 	/*
1008 	 * Mutex acquire failed. So there is currently another task
1009 	 * already running the AP bus scan. Then let's simple wait
1010 	 * for the lock which means the other task has finished and
1011 	 * stored the result in ap_scan_bus_result.
1012 	 */
1013 	if (mutex_lock_interruptible(&ap_scan_bus_mutex)) {
1014 		/* some error occurred, ignore and go out */
1015 		goto out;
1016 	}
1017 	rc = ap_scan_bus_result;
1018 	mutex_unlock(&ap_scan_bus_mutex);
1019 
1020 out:
1021 	pr_debug("%s rc=%d\n", __func__, rc);
1022 	return rc;
1023 }
1024 EXPORT_SYMBOL(ap_bus_force_rescan);
1025 
1026 /*
1027  * A config change has happened, force an ap bus rescan.
1028  */
1029 static int ap_bus_cfg_chg(struct notifier_block *nb,
1030 			  unsigned long action, void *data)
1031 {
1032 	if (action != CHSC_NOTIFY_AP_CFG)
1033 		return NOTIFY_DONE;
1034 
1035 	pr_debug("%s config change, forcing bus rescan\n", __func__);
1036 
1037 	ap_bus_force_rescan();
1038 
1039 	return NOTIFY_OK;
1040 }
1041 
1042 static struct notifier_block ap_bus_nb = {
1043 	.notifier_call = ap_bus_cfg_chg,
1044 };
1045 
1046 /*
1047  * hex2bitmap() - parse hex mask string and set bitmap.
1048  * Valid strings are "0x012345678" with at least one valid hex number.
1049  * Rest of the bitmap to the right is padded with 0. No spaces allowed
1050  * within the string, the leading 0x may be omitted.
1051  * Returns the bitmask with exactly the bits set as given by the hex
1052  * string (both in big endian order).
1053  */
1054 static int hex2bitmap(const char *str, unsigned long *bitmap, int bits)
1055 {
1056 	int i, n, b;
1057 
1058 	/* bits needs to be a multiple of 8 */
1059 	if (bits & 0x07)
1060 		return -EINVAL;
1061 
1062 	if (str[0] == '0' && str[1] == 'x')
1063 		str++;
1064 	if (*str == 'x')
1065 		str++;
1066 
1067 	for (i = 0; isxdigit(*str) && i < bits; str++) {
1068 		b = hex_to_bin(*str);
1069 		for (n = 0; n < 4; n++)
1070 			if (b & (0x08 >> n))
1071 				set_bit_inv(i + n, bitmap);
1072 		i += 4;
1073 	}
1074 
1075 	if (*str == '\n')
1076 		str++;
1077 	if (*str)
1078 		return -EINVAL;
1079 	return 0;
1080 }
1081 
1082 /*
1083  * modify_bitmap() - parse bitmask argument and modify an existing
1084  * bit mask accordingly. A concatenation (done with ',') of these
1085  * terms is recognized:
1086  *   +<bitnr>[-<bitnr>] or -<bitnr>[-<bitnr>]
1087  * <bitnr> may be any valid number (hex, decimal or octal) in the range
1088  * 0...bits-1; the leading + or - is required. Here are some examples:
1089  *   +0-15,+32,-128,-0xFF
1090  *   -0-255,+1-16,+0x128
1091  *   +1,+2,+3,+4,-5,-7-10
1092  * Returns the new bitmap after all changes have been applied. Every
1093  * positive value in the string will set a bit and every negative value
1094  * in the string will clear a bit. As a bit may be touched more than once,
1095  * the last 'operation' wins:
1096  * +0-255,-128 = first bits 0-255 will be set, then bit 128 will be
1097  * cleared again. All other bits are unmodified.
1098  */
1099 static int modify_bitmap(const char *str, unsigned long *bitmap, int bits)
1100 {
1101 	int a, i, z;
1102 	char *np, sign;
1103 
1104 	/* bits needs to be a multiple of 8 */
1105 	if (bits & 0x07)
1106 		return -EINVAL;
1107 
1108 	while (*str) {
1109 		sign = *str++;
1110 		if (sign != '+' && sign != '-')
1111 			return -EINVAL;
1112 		a = z = simple_strtoul(str, &np, 0);
1113 		if (str == np || a >= bits)
1114 			return -EINVAL;
1115 		str = np;
1116 		if (*str == '-') {
1117 			z = simple_strtoul(++str, &np, 0);
1118 			if (str == np || a > z || z >= bits)
1119 				return -EINVAL;
1120 			str = np;
1121 		}
1122 		for (i = a; i <= z; i++)
1123 			if (sign == '+')
1124 				set_bit_inv(i, bitmap);
1125 			else
1126 				clear_bit_inv(i, bitmap);
1127 		while (*str == ',' || *str == '\n')
1128 			str++;
1129 	}
1130 
1131 	return 0;
1132 }
1133 
1134 static int ap_parse_bitmap_str(const char *str, unsigned long *bitmap, int bits,
1135 			       unsigned long *newmap)
1136 {
1137 	unsigned long size;
1138 	int rc;
1139 
1140 	size = BITS_TO_LONGS(bits) * sizeof(unsigned long);
1141 	if (*str == '+' || *str == '-') {
1142 		memcpy(newmap, bitmap, size);
1143 		rc = modify_bitmap(str, newmap, bits);
1144 	} else {
1145 		memset(newmap, 0, size);
1146 		rc = hex2bitmap(str, newmap, bits);
1147 	}
1148 	return rc;
1149 }
1150 
1151 int ap_parse_mask_str(const char *str,
1152 		      unsigned long *bitmap, int bits,
1153 		      struct mutex *lock)
1154 {
1155 	unsigned long *newmap, size;
1156 	int rc;
1157 
1158 	/* bits needs to be a multiple of 8 */
1159 	if (bits & 0x07)
1160 		return -EINVAL;
1161 
1162 	size = BITS_TO_LONGS(bits) * sizeof(unsigned long);
1163 	newmap = kmalloc(size, GFP_KERNEL);
1164 	if (!newmap)
1165 		return -ENOMEM;
1166 	if (mutex_lock_interruptible(lock)) {
1167 		kfree(newmap);
1168 		return -ERESTARTSYS;
1169 	}
1170 	rc = ap_parse_bitmap_str(str, bitmap, bits, newmap);
1171 	if (rc == 0)
1172 		memcpy(bitmap, newmap, size);
1173 	mutex_unlock(lock);
1174 	kfree(newmap);
1175 	return rc;
1176 }
1177 EXPORT_SYMBOL(ap_parse_mask_str);
1178 
1179 /*
1180  * AP bus attributes.
1181  */
1182 
1183 static ssize_t ap_domain_show(const struct bus_type *bus, char *buf)
1184 {
1185 	return sysfs_emit(buf, "%d\n", ap_domain_index);
1186 }
1187 
1188 static ssize_t ap_domain_store(const struct bus_type *bus,
1189 			       const char *buf, size_t count)
1190 {
1191 	int domain;
1192 
1193 	if (sscanf(buf, "%i\n", &domain) != 1 ||
1194 	    domain < 0 || domain > ap_max_domain_id ||
1195 	    !test_bit_inv(domain, ap_perms.aqm))
1196 		return -EINVAL;
1197 
1198 	spin_lock_bh(&ap_domain_lock);
1199 	ap_domain_index = domain;
1200 	spin_unlock_bh(&ap_domain_lock);
1201 
1202 	AP_DBF_INFO("%s stored new default domain=%d\n",
1203 		    __func__, domain);
1204 
1205 	return count;
1206 }
1207 
1208 static BUS_ATTR_RW(ap_domain);
1209 
1210 static ssize_t ap_control_domain_mask_show(const struct bus_type *bus, char *buf)
1211 {
1212 	if (!ap_qci_info->flags)	/* QCI not supported */
1213 		return sysfs_emit(buf, "not supported\n");
1214 
1215 	return sysfs_emit(buf, "0x%08x%08x%08x%08x%08x%08x%08x%08x\n",
1216 			  ap_qci_info->adm[0], ap_qci_info->adm[1],
1217 			  ap_qci_info->adm[2], ap_qci_info->adm[3],
1218 			  ap_qci_info->adm[4], ap_qci_info->adm[5],
1219 			  ap_qci_info->adm[6], ap_qci_info->adm[7]);
1220 }
1221 
1222 static BUS_ATTR_RO(ap_control_domain_mask);
1223 
1224 static ssize_t ap_usage_domain_mask_show(const struct bus_type *bus, char *buf)
1225 {
1226 	if (!ap_qci_info->flags)	/* QCI not supported */
1227 		return sysfs_emit(buf, "not supported\n");
1228 
1229 	return sysfs_emit(buf, "0x%08x%08x%08x%08x%08x%08x%08x%08x\n",
1230 			  ap_qci_info->aqm[0], ap_qci_info->aqm[1],
1231 			  ap_qci_info->aqm[2], ap_qci_info->aqm[3],
1232 			  ap_qci_info->aqm[4], ap_qci_info->aqm[5],
1233 			  ap_qci_info->aqm[6], ap_qci_info->aqm[7]);
1234 }
1235 
1236 static BUS_ATTR_RO(ap_usage_domain_mask);
1237 
1238 static ssize_t ap_adapter_mask_show(const struct bus_type *bus, char *buf)
1239 {
1240 	if (!ap_qci_info->flags)	/* QCI not supported */
1241 		return sysfs_emit(buf, "not supported\n");
1242 
1243 	return sysfs_emit(buf, "0x%08x%08x%08x%08x%08x%08x%08x%08x\n",
1244 			  ap_qci_info->apm[0], ap_qci_info->apm[1],
1245 			  ap_qci_info->apm[2], ap_qci_info->apm[3],
1246 			  ap_qci_info->apm[4], ap_qci_info->apm[5],
1247 			  ap_qci_info->apm[6], ap_qci_info->apm[7]);
1248 }
1249 
1250 static BUS_ATTR_RO(ap_adapter_mask);
1251 
1252 static ssize_t ap_interrupts_show(const struct bus_type *bus, char *buf)
1253 {
1254 	return sysfs_emit(buf, "%d\n", ap_irq_flag ? 1 : 0);
1255 }
1256 
1257 static BUS_ATTR_RO(ap_interrupts);
1258 
1259 static ssize_t config_time_show(const struct bus_type *bus, char *buf)
1260 {
1261 	return sysfs_emit(buf, "%d\n", ap_scan_bus_time);
1262 }
1263 
1264 static ssize_t config_time_store(const struct bus_type *bus,
1265 				 const char *buf, size_t count)
1266 {
1267 	int time;
1268 
1269 	if (sscanf(buf, "%d\n", &time) != 1 || time < 5 || time > 120)
1270 		return -EINVAL;
1271 	ap_scan_bus_time = time;
1272 	mod_timer(&ap_scan_bus_timer, jiffies + ap_scan_bus_time * HZ);
1273 	return count;
1274 }
1275 
1276 static BUS_ATTR_RW(config_time);
1277 
1278 static ssize_t poll_thread_show(const struct bus_type *bus, char *buf)
1279 {
1280 	return sysfs_emit(buf, "%d\n", ap_poll_kthread ? 1 : 0);
1281 }
1282 
1283 static ssize_t poll_thread_store(const struct bus_type *bus,
1284 				 const char *buf, size_t count)
1285 {
1286 	bool value;
1287 	int rc;
1288 
1289 	rc = kstrtobool(buf, &value);
1290 	if (rc)
1291 		return rc;
1292 
1293 	if (value) {
1294 		rc = ap_poll_thread_start();
1295 		if (rc)
1296 			count = rc;
1297 	} else {
1298 		ap_poll_thread_stop();
1299 	}
1300 	return count;
1301 }
1302 
1303 static BUS_ATTR_RW(poll_thread);
1304 
1305 static ssize_t poll_timeout_show(const struct bus_type *bus, char *buf)
1306 {
1307 	return sysfs_emit(buf, "%lu\n", poll_high_timeout);
1308 }
1309 
1310 static ssize_t poll_timeout_store(const struct bus_type *bus, const char *buf,
1311 				  size_t count)
1312 {
1313 	unsigned long value;
1314 	ktime_t hr_time;
1315 	int rc;
1316 
1317 	rc = kstrtoul(buf, 0, &value);
1318 	if (rc)
1319 		return rc;
1320 
1321 	/* 120 seconds = maximum poll interval */
1322 	if (value > 120000000000UL)
1323 		return -EINVAL;
1324 	poll_high_timeout = value;
1325 	hr_time = poll_high_timeout;
1326 
1327 	spin_lock_bh(&ap_poll_timer_lock);
1328 	hrtimer_cancel(&ap_poll_timer);
1329 	hrtimer_set_expires(&ap_poll_timer, hr_time);
1330 	hrtimer_start_expires(&ap_poll_timer, HRTIMER_MODE_ABS);
1331 	spin_unlock_bh(&ap_poll_timer_lock);
1332 
1333 	return count;
1334 }
1335 
1336 static BUS_ATTR_RW(poll_timeout);
1337 
1338 static ssize_t ap_max_domain_id_show(const struct bus_type *bus, char *buf)
1339 {
1340 	return sysfs_emit(buf, "%d\n", ap_max_domain_id);
1341 }
1342 
1343 static BUS_ATTR_RO(ap_max_domain_id);
1344 
1345 static ssize_t ap_max_adapter_id_show(const struct bus_type *bus, char *buf)
1346 {
1347 	return sysfs_emit(buf, "%d\n", ap_max_adapter_id);
1348 }
1349 
1350 static BUS_ATTR_RO(ap_max_adapter_id);
1351 
1352 static ssize_t apmask_show(const struct bus_type *bus, char *buf)
1353 {
1354 	int rc;
1355 
1356 	if (mutex_lock_interruptible(&ap_perms_mutex))
1357 		return -ERESTARTSYS;
1358 	rc = sysfs_emit(buf, "0x%016lx%016lx%016lx%016lx\n",
1359 			ap_perms.apm[0], ap_perms.apm[1],
1360 			ap_perms.apm[2], ap_perms.apm[3]);
1361 	mutex_unlock(&ap_perms_mutex);
1362 
1363 	return rc;
1364 }
1365 
1366 static int __verify_card_reservations(struct device_driver *drv, void *data)
1367 {
1368 	int rc = 0;
1369 	struct ap_driver *ap_drv = to_ap_drv(drv);
1370 	unsigned long *newapm = (unsigned long *)data;
1371 
1372 	/*
1373 	 * increase the driver's module refcounter to be sure it is not
1374 	 * going away when we invoke the callback function.
1375 	 */
1376 	if (!try_module_get(drv->owner))
1377 		return 0;
1378 
1379 	if (ap_drv->in_use) {
1380 		rc = ap_drv->in_use(newapm, ap_perms.aqm);
1381 		if (rc)
1382 			rc = -EBUSY;
1383 	}
1384 
1385 	/* release the driver's module */
1386 	module_put(drv->owner);
1387 
1388 	return rc;
1389 }
1390 
1391 static int apmask_commit(unsigned long *newapm)
1392 {
1393 	int rc;
1394 	unsigned long reserved[BITS_TO_LONGS(AP_DEVICES)];
1395 
1396 	/*
1397 	 * Check if any bits in the apmask have been set which will
1398 	 * result in queues being removed from non-default drivers
1399 	 */
1400 	if (bitmap_andnot(reserved, newapm, ap_perms.apm, AP_DEVICES)) {
1401 		rc = bus_for_each_drv(&ap_bus_type, NULL, reserved,
1402 				      __verify_card_reservations);
1403 		if (rc)
1404 			return rc;
1405 	}
1406 
1407 	memcpy(ap_perms.apm, newapm, APMASKSIZE);
1408 
1409 	return 0;
1410 }
1411 
1412 static ssize_t apmask_store(const struct bus_type *bus, const char *buf,
1413 			    size_t count)
1414 {
1415 	int rc, changes = 0;
1416 	DECLARE_BITMAP(newapm, AP_DEVICES);
1417 
1418 	if (mutex_lock_interruptible(&ap_perms_mutex))
1419 		return -ERESTARTSYS;
1420 
1421 	rc = ap_parse_bitmap_str(buf, ap_perms.apm, AP_DEVICES, newapm);
1422 	if (rc)
1423 		goto done;
1424 
1425 	changes = memcmp(ap_perms.apm, newapm, APMASKSIZE);
1426 	if (changes)
1427 		rc = apmask_commit(newapm);
1428 
1429 done:
1430 	mutex_unlock(&ap_perms_mutex);
1431 	if (rc)
1432 		return rc;
1433 
1434 	if (changes) {
1435 		ap_bus_revise_bindings();
1436 		ap_send_mask_changed_uevent(newapm, NULL);
1437 	}
1438 
1439 	return count;
1440 }
1441 
1442 static BUS_ATTR_RW(apmask);
1443 
1444 static ssize_t aqmask_show(const struct bus_type *bus, char *buf)
1445 {
1446 	int rc;
1447 
1448 	if (mutex_lock_interruptible(&ap_perms_mutex))
1449 		return -ERESTARTSYS;
1450 	rc = sysfs_emit(buf, "0x%016lx%016lx%016lx%016lx\n",
1451 			ap_perms.aqm[0], ap_perms.aqm[1],
1452 			ap_perms.aqm[2], ap_perms.aqm[3]);
1453 	mutex_unlock(&ap_perms_mutex);
1454 
1455 	return rc;
1456 }
1457 
1458 static int __verify_queue_reservations(struct device_driver *drv, void *data)
1459 {
1460 	int rc = 0;
1461 	struct ap_driver *ap_drv = to_ap_drv(drv);
1462 	unsigned long *newaqm = (unsigned long *)data;
1463 
1464 	/*
1465 	 * increase the driver's module refcounter to be sure it is not
1466 	 * going away when we invoke the callback function.
1467 	 */
1468 	if (!try_module_get(drv->owner))
1469 		return 0;
1470 
1471 	if (ap_drv->in_use) {
1472 		rc = ap_drv->in_use(ap_perms.apm, newaqm);
1473 		if (rc)
1474 			rc = -EBUSY;
1475 	}
1476 
1477 	/* release the driver's module */
1478 	module_put(drv->owner);
1479 
1480 	return rc;
1481 }
1482 
1483 static int aqmask_commit(unsigned long *newaqm)
1484 {
1485 	int rc;
1486 	unsigned long reserved[BITS_TO_LONGS(AP_DOMAINS)];
1487 
1488 	/*
1489 	 * Check if any bits in the aqmask have been set which will
1490 	 * result in queues being removed from non-default drivers
1491 	 */
1492 	if (bitmap_andnot(reserved, newaqm, ap_perms.aqm, AP_DOMAINS)) {
1493 		rc = bus_for_each_drv(&ap_bus_type, NULL, reserved,
1494 				      __verify_queue_reservations);
1495 		if (rc)
1496 			return rc;
1497 	}
1498 
1499 	memcpy(ap_perms.aqm, newaqm, AQMASKSIZE);
1500 
1501 	return 0;
1502 }
1503 
1504 static ssize_t aqmask_store(const struct bus_type *bus, const char *buf,
1505 			    size_t count)
1506 {
1507 	int rc, changes = 0;
1508 	DECLARE_BITMAP(newaqm, AP_DOMAINS);
1509 
1510 	if (mutex_lock_interruptible(&ap_perms_mutex))
1511 		return -ERESTARTSYS;
1512 
1513 	rc = ap_parse_bitmap_str(buf, ap_perms.aqm, AP_DOMAINS, newaqm);
1514 	if (rc)
1515 		goto done;
1516 
1517 	changes = memcmp(ap_perms.aqm, newaqm, APMASKSIZE);
1518 	if (changes)
1519 		rc = aqmask_commit(newaqm);
1520 
1521 done:
1522 	mutex_unlock(&ap_perms_mutex);
1523 	if (rc)
1524 		return rc;
1525 
1526 	if (changes) {
1527 		ap_bus_revise_bindings();
1528 		ap_send_mask_changed_uevent(NULL, newaqm);
1529 	}
1530 
1531 	return count;
1532 }
1533 
1534 static BUS_ATTR_RW(aqmask);
1535 
1536 static ssize_t scans_show(const struct bus_type *bus, char *buf)
1537 {
1538 	return sysfs_emit(buf, "%llu\n", atomic64_read(&ap_scan_bus_count));
1539 }
1540 
1541 static ssize_t scans_store(const struct bus_type *bus, const char *buf,
1542 			   size_t count)
1543 {
1544 	AP_DBF_INFO("%s force AP bus rescan\n", __func__);
1545 
1546 	ap_bus_force_rescan();
1547 
1548 	return count;
1549 }
1550 
1551 static BUS_ATTR_RW(scans);
1552 
1553 static ssize_t bindings_show(const struct bus_type *bus, char *buf)
1554 {
1555 	int rc;
1556 	unsigned int apqns, n;
1557 
1558 	ap_calc_bound_apqns(&apqns, &n);
1559 	if (atomic64_read(&ap_scan_bus_count) >= 1 && n == apqns)
1560 		rc = sysfs_emit(buf, "%u/%u (complete)\n", n, apqns);
1561 	else
1562 		rc = sysfs_emit(buf, "%u/%u\n", n, apqns);
1563 
1564 	return rc;
1565 }
1566 
1567 static BUS_ATTR_RO(bindings);
1568 
1569 static ssize_t features_show(const struct bus_type *bus, char *buf)
1570 {
1571 	int n = 0;
1572 
1573 	if (!ap_qci_info->flags)	/* QCI not supported */
1574 		return sysfs_emit(buf, "-\n");
1575 
1576 	if (ap_qci_info->apsc)
1577 		n += sysfs_emit_at(buf, n, "APSC ");
1578 	if (ap_qci_info->apxa)
1579 		n += sysfs_emit_at(buf, n, "APXA ");
1580 	if (ap_qci_info->qact)
1581 		n += sysfs_emit_at(buf, n, "QACT ");
1582 	if (ap_qci_info->rc8a)
1583 		n += sysfs_emit_at(buf, n, "RC8A ");
1584 	if (ap_qci_info->apsb)
1585 		n += sysfs_emit_at(buf, n, "APSB ");
1586 
1587 	sysfs_emit_at(buf, n == 0 ? 0 : n - 1, "\n");
1588 
1589 	return n;
1590 }
1591 
1592 static BUS_ATTR_RO(features);
1593 
1594 static struct attribute *ap_bus_attrs[] = {
1595 	&bus_attr_ap_domain.attr,
1596 	&bus_attr_ap_control_domain_mask.attr,
1597 	&bus_attr_ap_usage_domain_mask.attr,
1598 	&bus_attr_ap_adapter_mask.attr,
1599 	&bus_attr_config_time.attr,
1600 	&bus_attr_poll_thread.attr,
1601 	&bus_attr_ap_interrupts.attr,
1602 	&bus_attr_poll_timeout.attr,
1603 	&bus_attr_ap_max_domain_id.attr,
1604 	&bus_attr_ap_max_adapter_id.attr,
1605 	&bus_attr_apmask.attr,
1606 	&bus_attr_aqmask.attr,
1607 	&bus_attr_scans.attr,
1608 	&bus_attr_bindings.attr,
1609 	&bus_attr_features.attr,
1610 	NULL,
1611 };
1612 ATTRIBUTE_GROUPS(ap_bus);
1613 
1614 static const struct bus_type ap_bus_type = {
1615 	.name = "ap",
1616 	.bus_groups = ap_bus_groups,
1617 	.match = &ap_bus_match,
1618 	.uevent = &ap_uevent,
1619 	.probe = ap_device_probe,
1620 	.remove = ap_device_remove,
1621 };
1622 
1623 /**
1624  * ap_select_domain(): Select an AP domain if possible and we haven't
1625  * already done so before.
1626  */
1627 static void ap_select_domain(void)
1628 {
1629 	struct ap_queue_status status;
1630 	int card, dom;
1631 
1632 	/*
1633 	 * Choose the default domain. Either the one specified with
1634 	 * the "domain=" parameter or the first domain with at least
1635 	 * one valid APQN.
1636 	 */
1637 	spin_lock_bh(&ap_domain_lock);
1638 	if (ap_domain_index >= 0) {
1639 		/* Domain has already been selected. */
1640 		goto out;
1641 	}
1642 	for (dom = 0; dom <= ap_max_domain_id; dom++) {
1643 		if (!ap_test_config_usage_domain(dom) ||
1644 		    !test_bit_inv(dom, ap_perms.aqm))
1645 			continue;
1646 		for (card = 0; card <= ap_max_adapter_id; card++) {
1647 			if (!ap_test_config_card_id(card) ||
1648 			    !test_bit_inv(card, ap_perms.apm))
1649 				continue;
1650 			status = ap_test_queue(AP_MKQID(card, dom),
1651 					       ap_apft_available(),
1652 					       NULL);
1653 			if (status.response_code == AP_RESPONSE_NORMAL)
1654 				break;
1655 		}
1656 		if (card <= ap_max_adapter_id)
1657 			break;
1658 	}
1659 	if (dom <= ap_max_domain_id) {
1660 		ap_domain_index = dom;
1661 		AP_DBF_INFO("%s new default domain is %d\n",
1662 			    __func__, ap_domain_index);
1663 	}
1664 out:
1665 	spin_unlock_bh(&ap_domain_lock);
1666 }
1667 
1668 /*
1669  * This function checks the type and returns either 0 for not
1670  * supported or the highest compatible type value (which may
1671  * include the input type value).
1672  */
1673 static int ap_get_compatible_type(ap_qid_t qid, int rawtype, unsigned int func)
1674 {
1675 	int comp_type = 0;
1676 
1677 	/* < CEX4 is not supported */
1678 	if (rawtype < AP_DEVICE_TYPE_CEX4) {
1679 		AP_DBF_WARN("%s queue=%02x.%04x unsupported type %d\n",
1680 			    __func__, AP_QID_CARD(qid),
1681 			    AP_QID_QUEUE(qid), rawtype);
1682 		return 0;
1683 	}
1684 	/* up to CEX8 known and fully supported */
1685 	if (rawtype <= AP_DEVICE_TYPE_CEX8)
1686 		return rawtype;
1687 	/*
1688 	 * unknown new type > CEX8, check for compatibility
1689 	 * to the highest known and supported type which is
1690 	 * currently CEX8 with the help of the QACT function.
1691 	 */
1692 	if (ap_qact_available()) {
1693 		struct ap_queue_status status;
1694 		union ap_qact_ap_info apinfo = {0};
1695 
1696 		apinfo.mode = (func >> 26) & 0x07;
1697 		apinfo.cat = AP_DEVICE_TYPE_CEX8;
1698 		status = ap_qact(qid, 0, &apinfo);
1699 		if (status.response_code == AP_RESPONSE_NORMAL &&
1700 		    apinfo.cat >= AP_DEVICE_TYPE_CEX4 &&
1701 		    apinfo.cat <= AP_DEVICE_TYPE_CEX8)
1702 			comp_type = apinfo.cat;
1703 	}
1704 	if (!comp_type)
1705 		AP_DBF_WARN("%s queue=%02x.%04x unable to map type %d\n",
1706 			    __func__, AP_QID_CARD(qid),
1707 			    AP_QID_QUEUE(qid), rawtype);
1708 	else if (comp_type != rawtype)
1709 		AP_DBF_INFO("%s queue=%02x.%04x map type %d to %d\n",
1710 			    __func__, AP_QID_CARD(qid), AP_QID_QUEUE(qid),
1711 			    rawtype, comp_type);
1712 	return comp_type;
1713 }
1714 
1715 /*
1716  * Helper function to be used with bus_find_dev
1717  * matches for the card device with the given id
1718  */
1719 static int __match_card_device_with_id(struct device *dev, const void *data)
1720 {
1721 	return is_card_dev(dev) && to_ap_card(dev)->id == (int)(long)(void *)data;
1722 }
1723 
1724 /*
1725  * Helper function to be used with bus_find_dev
1726  * matches for the queue device with a given qid
1727  */
1728 static int __match_queue_device_with_qid(struct device *dev, const void *data)
1729 {
1730 	return is_queue_dev(dev) && to_ap_queue(dev)->qid == (int)(long)data;
1731 }
1732 
1733 /*
1734  * Helper function to be used with bus_find_dev
1735  * matches any queue device with given queue id
1736  */
1737 static int __match_queue_device_with_queue_id(struct device *dev, const void *data)
1738 {
1739 	return is_queue_dev(dev) &&
1740 		AP_QID_QUEUE(to_ap_queue(dev)->qid) == (int)(long)data;
1741 }
1742 
1743 /* Helper function for notify_config_changed */
1744 static int __drv_notify_config_changed(struct device_driver *drv, void *data)
1745 {
1746 	struct ap_driver *ap_drv = to_ap_drv(drv);
1747 
1748 	if (try_module_get(drv->owner)) {
1749 		if (ap_drv->on_config_changed)
1750 			ap_drv->on_config_changed(ap_qci_info, ap_qci_info_old);
1751 		module_put(drv->owner);
1752 	}
1753 
1754 	return 0;
1755 }
1756 
1757 /* Notify all drivers about an qci config change */
1758 static inline void notify_config_changed(void)
1759 {
1760 	bus_for_each_drv(&ap_bus_type, NULL, NULL,
1761 			 __drv_notify_config_changed);
1762 }
1763 
1764 /* Helper function for notify_scan_complete */
1765 static int __drv_notify_scan_complete(struct device_driver *drv, void *data)
1766 {
1767 	struct ap_driver *ap_drv = to_ap_drv(drv);
1768 
1769 	if (try_module_get(drv->owner)) {
1770 		if (ap_drv->on_scan_complete)
1771 			ap_drv->on_scan_complete(ap_qci_info,
1772 						 ap_qci_info_old);
1773 		module_put(drv->owner);
1774 	}
1775 
1776 	return 0;
1777 }
1778 
1779 /* Notify all drivers about bus scan complete */
1780 static inline void notify_scan_complete(void)
1781 {
1782 	bus_for_each_drv(&ap_bus_type, NULL, NULL,
1783 			 __drv_notify_scan_complete);
1784 }
1785 
1786 /*
1787  * Helper function for ap_scan_bus().
1788  * Remove card device and associated queue devices.
1789  */
1790 static inline void ap_scan_rm_card_dev_and_queue_devs(struct ap_card *ac)
1791 {
1792 	bus_for_each_dev(&ap_bus_type, NULL,
1793 			 (void *)(long)ac->id,
1794 			 __ap_queue_devices_with_id_unregister);
1795 	device_unregister(&ac->ap_dev.device);
1796 }
1797 
1798 /*
1799  * Helper function for ap_scan_bus().
1800  * Does the scan bus job for all the domains within
1801  * a valid adapter given by an ap_card ptr.
1802  */
1803 static inline void ap_scan_domains(struct ap_card *ac)
1804 {
1805 	struct ap_tapq_hwinfo hwinfo;
1806 	bool decfg, chkstop;
1807 	struct ap_queue *aq;
1808 	struct device *dev;
1809 	ap_qid_t qid;
1810 	int rc, dom;
1811 
1812 	/*
1813 	 * Go through the configuration for the domains and compare them
1814 	 * to the existing queue devices. Also take care of the config
1815 	 * and error state for the queue devices.
1816 	 */
1817 
1818 	for (dom = 0; dom <= ap_max_domain_id; dom++) {
1819 		qid = AP_MKQID(ac->id, dom);
1820 		dev = bus_find_device(&ap_bus_type, NULL,
1821 				      (void *)(long)qid,
1822 				      __match_queue_device_with_qid);
1823 		aq = dev ? to_ap_queue(dev) : NULL;
1824 		if (!ap_test_config_usage_domain(dom)) {
1825 			if (dev) {
1826 				AP_DBF_INFO("%s(%d,%d) not in config anymore, rm queue dev\n",
1827 					    __func__, ac->id, dom);
1828 				device_unregister(dev);
1829 			}
1830 			goto put_dev_and_continue;
1831 		}
1832 		/* domain is valid, get info from this APQN */
1833 		rc = ap_queue_info(qid, &hwinfo, &decfg, &chkstop);
1834 		switch (rc) {
1835 		case -1:
1836 			if (dev) {
1837 				AP_DBF_INFO("%s(%d,%d) queue_info() failed, rm queue dev\n",
1838 					    __func__, ac->id, dom);
1839 				device_unregister(dev);
1840 			}
1841 			fallthrough;
1842 		case 0:
1843 			goto put_dev_and_continue;
1844 		default:
1845 			break;
1846 		}
1847 		/* if no queue device exists, create a new one */
1848 		if (!aq) {
1849 			aq = ap_queue_create(qid, ac->ap_dev.device_type);
1850 			if (!aq) {
1851 				AP_DBF_WARN("%s(%d,%d) ap_queue_create() failed\n",
1852 					    __func__, ac->id, dom);
1853 				continue;
1854 			}
1855 			aq->card = ac;
1856 			aq->config = !decfg;
1857 			aq->chkstop = chkstop;
1858 			aq->se_bstate = hwinfo.bs;
1859 			dev = &aq->ap_dev.device;
1860 			dev->bus = &ap_bus_type;
1861 			dev->parent = &ac->ap_dev.device;
1862 			dev_set_name(dev, "%02x.%04x", ac->id, dom);
1863 			/* register queue device */
1864 			rc = device_register(dev);
1865 			if (rc) {
1866 				AP_DBF_WARN("%s(%d,%d) device_register() failed\n",
1867 					    __func__, ac->id, dom);
1868 				goto put_dev_and_continue;
1869 			}
1870 			/* get it and thus adjust reference counter */
1871 			get_device(dev);
1872 			if (decfg) {
1873 				AP_DBF_INFO("%s(%d,%d) new (decfg) queue dev created\n",
1874 					    __func__, ac->id, dom);
1875 			} else if (chkstop) {
1876 				AP_DBF_INFO("%s(%d,%d) new (chkstop) queue dev created\n",
1877 					    __func__, ac->id, dom);
1878 			} else {
1879 				/* nudge the queue's state machine */
1880 				ap_queue_init_state(aq);
1881 				AP_DBF_INFO("%s(%d,%d) new queue dev created\n",
1882 					    __func__, ac->id, dom);
1883 			}
1884 			goto put_dev_and_continue;
1885 		}
1886 		/* handle state changes on already existing queue device */
1887 		spin_lock_bh(&aq->lock);
1888 		/* SE bind state */
1889 		aq->se_bstate = hwinfo.bs;
1890 		/* checkstop state */
1891 		if (chkstop && !aq->chkstop) {
1892 			/* checkstop on */
1893 			aq->chkstop = true;
1894 			if (aq->dev_state > AP_DEV_STATE_UNINITIATED) {
1895 				aq->dev_state = AP_DEV_STATE_ERROR;
1896 				aq->last_err_rc = AP_RESPONSE_CHECKSTOPPED;
1897 			}
1898 			spin_unlock_bh(&aq->lock);
1899 			pr_debug("%s(%d,%d) queue dev checkstop on\n",
1900 				 __func__, ac->id, dom);
1901 			/* 'receive' pending messages with -EAGAIN */
1902 			ap_flush_queue(aq);
1903 			goto put_dev_and_continue;
1904 		} else if (!chkstop && aq->chkstop) {
1905 			/* checkstop off */
1906 			aq->chkstop = false;
1907 			if (aq->dev_state > AP_DEV_STATE_UNINITIATED)
1908 				_ap_queue_init_state(aq);
1909 			spin_unlock_bh(&aq->lock);
1910 			pr_debug("%s(%d,%d) queue dev checkstop off\n",
1911 				 __func__, ac->id, dom);
1912 			goto put_dev_and_continue;
1913 		}
1914 		/* config state change */
1915 		if (decfg && aq->config) {
1916 			/* config off this queue device */
1917 			aq->config = false;
1918 			if (aq->dev_state > AP_DEV_STATE_UNINITIATED) {
1919 				aq->dev_state = AP_DEV_STATE_ERROR;
1920 				aq->last_err_rc = AP_RESPONSE_DECONFIGURED;
1921 			}
1922 			spin_unlock_bh(&aq->lock);
1923 			pr_debug("%s(%d,%d) queue dev config off\n",
1924 				 __func__, ac->id, dom);
1925 			ap_send_config_uevent(&aq->ap_dev, aq->config);
1926 			/* 'receive' pending messages with -EAGAIN */
1927 			ap_flush_queue(aq);
1928 			goto put_dev_and_continue;
1929 		} else if (!decfg && !aq->config) {
1930 			/* config on this queue device */
1931 			aq->config = true;
1932 			if (aq->dev_state > AP_DEV_STATE_UNINITIATED)
1933 				_ap_queue_init_state(aq);
1934 			spin_unlock_bh(&aq->lock);
1935 			pr_debug("%s(%d,%d) queue dev config on\n",
1936 				 __func__, ac->id, dom);
1937 			ap_send_config_uevent(&aq->ap_dev, aq->config);
1938 			goto put_dev_and_continue;
1939 		}
1940 		/* handle other error states */
1941 		if (!decfg && aq->dev_state == AP_DEV_STATE_ERROR) {
1942 			spin_unlock_bh(&aq->lock);
1943 			/* 'receive' pending messages with -EAGAIN */
1944 			ap_flush_queue(aq);
1945 			/* re-init (with reset) the queue device */
1946 			ap_queue_init_state(aq);
1947 			AP_DBF_INFO("%s(%d,%d) queue dev reinit enforced\n",
1948 				    __func__, ac->id, dom);
1949 			goto put_dev_and_continue;
1950 		}
1951 		spin_unlock_bh(&aq->lock);
1952 put_dev_and_continue:
1953 		put_device(dev);
1954 	}
1955 }
1956 
1957 /*
1958  * Helper function for ap_scan_bus().
1959  * Does the scan bus job for the given adapter id.
1960  */
1961 static inline void ap_scan_adapter(int ap)
1962 {
1963 	struct ap_tapq_hwinfo hwinfo;
1964 	int rc, dom, comp_type;
1965 	bool decfg, chkstop;
1966 	struct ap_card *ac;
1967 	struct device *dev;
1968 	ap_qid_t qid;
1969 
1970 	/* Is there currently a card device for this adapter ? */
1971 	dev = bus_find_device(&ap_bus_type, NULL,
1972 			      (void *)(long)ap,
1973 			      __match_card_device_with_id);
1974 	ac = dev ? to_ap_card(dev) : NULL;
1975 
1976 	/* Adapter not in configuration ? */
1977 	if (!ap_test_config_card_id(ap)) {
1978 		if (ac) {
1979 			AP_DBF_INFO("%s(%d) ap not in config any more, rm card and queue devs\n",
1980 				    __func__, ap);
1981 			ap_scan_rm_card_dev_and_queue_devs(ac);
1982 			put_device(dev);
1983 		}
1984 		return;
1985 	}
1986 
1987 	/*
1988 	 * Adapter ap is valid in the current configuration. So do some checks:
1989 	 * If no card device exists, build one. If a card device exists, check
1990 	 * for type and functions changed. For all this we need to find a valid
1991 	 * APQN first.
1992 	 */
1993 
1994 	for (dom = 0; dom <= ap_max_domain_id; dom++)
1995 		if (ap_test_config_usage_domain(dom)) {
1996 			qid = AP_MKQID(ap, dom);
1997 			if (ap_queue_info(qid, &hwinfo, &decfg, &chkstop) > 0)
1998 				break;
1999 		}
2000 	if (dom > ap_max_domain_id) {
2001 		/* Could not find one valid APQN for this adapter */
2002 		if (ac) {
2003 			AP_DBF_INFO("%s(%d) no type info (no APQN found), rm card and queue devs\n",
2004 				    __func__, ap);
2005 			ap_scan_rm_card_dev_and_queue_devs(ac);
2006 			put_device(dev);
2007 		} else {
2008 			pr_debug("%s(%d) no type info (no APQN found), ignored\n",
2009 				 __func__, ap);
2010 		}
2011 		return;
2012 	}
2013 	if (!hwinfo.at) {
2014 		/* No apdater type info available, an unusable adapter */
2015 		if (ac) {
2016 			AP_DBF_INFO("%s(%d) no valid type (0) info, rm card and queue devs\n",
2017 				    __func__, ap);
2018 			ap_scan_rm_card_dev_and_queue_devs(ac);
2019 			put_device(dev);
2020 		} else {
2021 			pr_debug("%s(%d) no valid type (0) info, ignored\n",
2022 				 __func__, ap);
2023 		}
2024 		return;
2025 	}
2026 	hwinfo.value &= TAPQ_CARD_HWINFO_MASK; /* filter card specific hwinfo */
2027 	if (ac) {
2028 		/* Check APQN against existing card device for changes */
2029 		if (ac->hwinfo.at != hwinfo.at) {
2030 			AP_DBF_INFO("%s(%d) hwtype %d changed, rm card and queue devs\n",
2031 				    __func__, ap, hwinfo.at);
2032 			ap_scan_rm_card_dev_and_queue_devs(ac);
2033 			put_device(dev);
2034 			ac = NULL;
2035 		} else if (ac->hwinfo.fac != hwinfo.fac) {
2036 			AP_DBF_INFO("%s(%d) functions 0x%08x changed, rm card and queue devs\n",
2037 				    __func__, ap, hwinfo.fac);
2038 			ap_scan_rm_card_dev_and_queue_devs(ac);
2039 			put_device(dev);
2040 			ac = NULL;
2041 		} else {
2042 			/* handle checkstop state change */
2043 			if (chkstop && !ac->chkstop) {
2044 				/* checkstop on */
2045 				ac->chkstop = true;
2046 				AP_DBF_INFO("%s(%d) card dev checkstop on\n",
2047 					    __func__, ap);
2048 			} else if (!chkstop && ac->chkstop) {
2049 				/* checkstop off */
2050 				ac->chkstop = false;
2051 				AP_DBF_INFO("%s(%d) card dev checkstop off\n",
2052 					    __func__, ap);
2053 			}
2054 			/* handle config state change */
2055 			if (decfg && ac->config) {
2056 				ac->config = false;
2057 				AP_DBF_INFO("%s(%d) card dev config off\n",
2058 					    __func__, ap);
2059 				ap_send_config_uevent(&ac->ap_dev, ac->config);
2060 			} else if (!decfg && !ac->config) {
2061 				ac->config = true;
2062 				AP_DBF_INFO("%s(%d) card dev config on\n",
2063 					    __func__, ap);
2064 				ap_send_config_uevent(&ac->ap_dev, ac->config);
2065 			}
2066 		}
2067 	}
2068 
2069 	if (!ac) {
2070 		/* Build a new card device */
2071 		comp_type = ap_get_compatible_type(qid, hwinfo.at, hwinfo.fac);
2072 		if (!comp_type) {
2073 			AP_DBF_WARN("%s(%d) type %d, can't get compatibility type\n",
2074 				    __func__, ap, hwinfo.at);
2075 			return;
2076 		}
2077 		ac = ap_card_create(ap, hwinfo, comp_type);
2078 		if (!ac) {
2079 			AP_DBF_WARN("%s(%d) ap_card_create() failed\n",
2080 				    __func__, ap);
2081 			return;
2082 		}
2083 		ac->config = !decfg;
2084 		ac->chkstop = chkstop;
2085 		dev = &ac->ap_dev.device;
2086 		dev->bus = &ap_bus_type;
2087 		dev->parent = ap_root_device;
2088 		dev_set_name(dev, "card%02x", ap);
2089 		/* maybe enlarge ap_max_msg_size to support this card */
2090 		if (ac->maxmsgsize > atomic_read(&ap_max_msg_size)) {
2091 			atomic_set(&ap_max_msg_size, ac->maxmsgsize);
2092 			AP_DBF_INFO("%s(%d) ap_max_msg_size update to %d byte\n",
2093 				    __func__, ap,
2094 				    atomic_read(&ap_max_msg_size));
2095 		}
2096 		/* Register the new card device with AP bus */
2097 		rc = device_register(dev);
2098 		if (rc) {
2099 			AP_DBF_WARN("%s(%d) device_register() failed\n",
2100 				    __func__, ap);
2101 			put_device(dev);
2102 			return;
2103 		}
2104 		/* get it and thus adjust reference counter */
2105 		get_device(dev);
2106 		if (decfg)
2107 			AP_DBF_INFO("%s(%d) new (decfg) card dev type=%d func=0x%08x created\n",
2108 				    __func__, ap, hwinfo.at, hwinfo.fac);
2109 		else if (chkstop)
2110 			AP_DBF_INFO("%s(%d) new (chkstop) card dev type=%d func=0x%08x created\n",
2111 				    __func__, ap, hwinfo.at, hwinfo.fac);
2112 		else
2113 			AP_DBF_INFO("%s(%d) new card dev type=%d func=0x%08x created\n",
2114 				    __func__, ap, hwinfo.at, hwinfo.fac);
2115 	}
2116 
2117 	/* Verify the domains and the queue devices for this card */
2118 	ap_scan_domains(ac);
2119 
2120 	/* release the card device */
2121 	put_device(&ac->ap_dev.device);
2122 }
2123 
2124 /**
2125  * ap_get_configuration - get the host AP configuration
2126  *
2127  * Stores the host AP configuration information returned from the previous call
2128  * to Query Configuration Information (QCI), then retrieves and stores the
2129  * current AP configuration returned from QCI.
2130  *
2131  * Return: true if the host AP configuration changed between calls to QCI;
2132  * otherwise, return false.
2133  */
2134 static bool ap_get_configuration(void)
2135 {
2136 	if (!ap_qci_info->flags)	/* QCI not supported */
2137 		return false;
2138 
2139 	memcpy(ap_qci_info_old, ap_qci_info, sizeof(*ap_qci_info));
2140 	ap_qci(ap_qci_info);
2141 
2142 	return memcmp(ap_qci_info, ap_qci_info_old,
2143 		      sizeof(struct ap_config_info)) != 0;
2144 }
2145 
2146 /*
2147  * ap_config_has_new_aps - Check current against old qci info if
2148  * new adapters have appeared. Returns true if at least one new
2149  * adapter in the apm mask is showing up. Existing adapters or
2150  * receding adapters are not counted.
2151  */
2152 static bool ap_config_has_new_aps(void)
2153 {
2154 
2155 	unsigned long m[BITS_TO_LONGS(AP_DEVICES)];
2156 
2157 	if (!ap_qci_info->flags)
2158 		return false;
2159 
2160 	bitmap_andnot(m, (unsigned long *)ap_qci_info->apm,
2161 		      (unsigned long *)ap_qci_info_old->apm, AP_DEVICES);
2162 	if (!bitmap_empty(m, AP_DEVICES))
2163 		return true;
2164 
2165 	return false;
2166 }
2167 
2168 /*
2169  * ap_config_has_new_doms - Check current against old qci info if
2170  * new (usage) domains have appeared. Returns true if at least one
2171  * new domain in the aqm mask is showing up. Existing domains or
2172  * receding domains are not counted.
2173  */
2174 static bool ap_config_has_new_doms(void)
2175 {
2176 	unsigned long m[BITS_TO_LONGS(AP_DOMAINS)];
2177 
2178 	if (!ap_qci_info->flags)
2179 		return false;
2180 
2181 	bitmap_andnot(m, (unsigned long *)ap_qci_info->aqm,
2182 		      (unsigned long *)ap_qci_info_old->aqm, AP_DOMAINS);
2183 	if (!bitmap_empty(m, AP_DOMAINS))
2184 		return true;
2185 
2186 	return false;
2187 }
2188 
2189 /**
2190  * ap_scan_bus(): Scan the AP bus for new devices
2191  * Always run under mutex ap_scan_bus_mutex protection
2192  * which needs to get locked/unlocked by the caller!
2193  * Returns true if any config change has been detected
2194  * during the scan, otherwise false.
2195  */
2196 static bool ap_scan_bus(void)
2197 {
2198 	bool config_changed;
2199 	int ap;
2200 
2201 	pr_debug(">%s\n", __func__);
2202 
2203 	/* (re-)fetch configuration via QCI */
2204 	config_changed = ap_get_configuration();
2205 	if (config_changed) {
2206 		if (ap_config_has_new_aps() || ap_config_has_new_doms()) {
2207 			/*
2208 			 * Appearance of new adapters and/or domains need to
2209 			 * build new ap devices which need to get bound to an
2210 			 * device driver. Thus reset the APQN bindings complete
2211 			 * completion.
2212 			 */
2213 			reinit_completion(&ap_apqn_bindings_complete);
2214 		}
2215 		/* post a config change notify */
2216 		notify_config_changed();
2217 	}
2218 	ap_select_domain();
2219 
2220 	/* loop over all possible adapters */
2221 	for (ap = 0; ap <= ap_max_adapter_id; ap++)
2222 		ap_scan_adapter(ap);
2223 
2224 	/* scan complete notify */
2225 	if (config_changed)
2226 		notify_scan_complete();
2227 
2228 	/* check if there is at least one queue available with default domain */
2229 	if (ap_domain_index >= 0) {
2230 		struct device *dev =
2231 			bus_find_device(&ap_bus_type, NULL,
2232 					(void *)(long)ap_domain_index,
2233 					__match_queue_device_with_queue_id);
2234 		if (dev)
2235 			put_device(dev);
2236 		else
2237 			AP_DBF_INFO("%s no queue device with default domain %d available\n",
2238 				    __func__, ap_domain_index);
2239 	}
2240 
2241 	if (atomic64_inc_return(&ap_scan_bus_count) == 1) {
2242 		pr_debug("%s init scan complete\n", __func__);
2243 		ap_send_init_scan_done_uevent();
2244 	}
2245 
2246 	ap_check_bindings_complete();
2247 
2248 	mod_timer(&ap_scan_bus_timer, jiffies + ap_scan_bus_time * HZ);
2249 
2250 	pr_debug("<%s config_changed=%d\n", __func__, config_changed);
2251 
2252 	return config_changed;
2253 }
2254 
2255 /*
2256  * Callback for the ap_scan_bus_timer
2257  * Runs periodically, workqueue timer (ap_scan_bus_time)
2258  */
2259 static void ap_scan_bus_timer_callback(struct timer_list *unused)
2260 {
2261 	/*
2262 	 * schedule work into the system long wq which when
2263 	 * the work is finally executed, calls the AP bus scan.
2264 	 */
2265 	queue_work(system_long_wq, &ap_scan_bus_work);
2266 }
2267 
2268 /*
2269  * Callback for the ap_scan_bus_work
2270  */
2271 static void ap_scan_bus_wq_callback(struct work_struct *unused)
2272 {
2273 	/*
2274 	 * Try to invoke an ap_scan_bus(). If the mutex acquisition
2275 	 * fails there is currently another task already running the
2276 	 * AP scan bus and there is no need to wait and re-trigger the
2277 	 * scan again. Please note at the end of the scan bus function
2278 	 * the AP scan bus timer is re-armed which triggers then the
2279 	 * ap_scan_bus_timer_callback which enqueues a work into the
2280 	 * system_long_wq which invokes this function here again.
2281 	 */
2282 	if (mutex_trylock(&ap_scan_bus_mutex)) {
2283 		ap_scan_bus_result = ap_scan_bus();
2284 		mutex_unlock(&ap_scan_bus_mutex);
2285 	}
2286 }
2287 
2288 static inline void __exit ap_async_exit(void)
2289 {
2290 	if (ap_thread_flag)
2291 		ap_poll_thread_stop();
2292 	chsc_notifier_unregister(&ap_bus_nb);
2293 	cancel_work(&ap_scan_bus_work);
2294 	hrtimer_cancel(&ap_poll_timer);
2295 	timer_delete(&ap_scan_bus_timer);
2296 }
2297 
2298 static inline int __init ap_async_init(void)
2299 {
2300 	int rc;
2301 
2302 	/* Setup the AP bus rescan timer. */
2303 	timer_setup(&ap_scan_bus_timer, ap_scan_bus_timer_callback, 0);
2304 
2305 	/*
2306 	 * Setup the high resolution poll timer.
2307 	 * If we are running under z/VM adjust polling to z/VM polling rate.
2308 	 */
2309 	if (MACHINE_IS_VM)
2310 		poll_high_timeout = 1500000;
2311 	hrtimer_init(&ap_poll_timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
2312 	ap_poll_timer.function = ap_poll_timeout;
2313 
2314 	queue_work(system_long_wq, &ap_scan_bus_work);
2315 
2316 	rc = chsc_notifier_register(&ap_bus_nb);
2317 	if (rc)
2318 		goto out;
2319 
2320 	/* Start the low priority AP bus poll thread. */
2321 	if (!ap_thread_flag)
2322 		return 0;
2323 
2324 	rc = ap_poll_thread_start();
2325 	if (rc)
2326 		goto out_notifier;
2327 
2328 	return 0;
2329 
2330 out_notifier:
2331 	chsc_notifier_unregister(&ap_bus_nb);
2332 out:
2333 	cancel_work(&ap_scan_bus_work);
2334 	hrtimer_cancel(&ap_poll_timer);
2335 	timer_delete(&ap_scan_bus_timer);
2336 	return rc;
2337 }
2338 
2339 static inline void ap_irq_exit(void)
2340 {
2341 	if (ap_irq_flag)
2342 		unregister_adapter_interrupt(&ap_airq);
2343 }
2344 
2345 static inline int __init ap_irq_init(void)
2346 {
2347 	int rc;
2348 
2349 	if (!ap_interrupts_available() || !ap_useirq)
2350 		return 0;
2351 
2352 	rc = register_adapter_interrupt(&ap_airq);
2353 	ap_irq_flag = (rc == 0);
2354 
2355 	return rc;
2356 }
2357 
2358 static inline void ap_debug_exit(void)
2359 {
2360 	debug_unregister(ap_dbf_info);
2361 }
2362 
2363 static inline int __init ap_debug_init(void)
2364 {
2365 	ap_dbf_info = debug_register("ap", 2, 1,
2366 				     AP_DBF_MAX_SPRINTF_ARGS * sizeof(long));
2367 	debug_register_view(ap_dbf_info, &debug_sprintf_view);
2368 	debug_set_level(ap_dbf_info, DBF_ERR);
2369 
2370 	return 0;
2371 }
2372 
2373 static void __init ap_perms_init(void)
2374 {
2375 	/* all resources usable if no kernel parameter string given */
2376 	memset(&ap_perms.ioctlm, 0xFF, sizeof(ap_perms.ioctlm));
2377 	memset(&ap_perms.apm, 0xFF, sizeof(ap_perms.apm));
2378 	memset(&ap_perms.aqm, 0xFF, sizeof(ap_perms.aqm));
2379 
2380 	/* apm kernel parameter string */
2381 	if (apm_str) {
2382 		memset(&ap_perms.apm, 0, sizeof(ap_perms.apm));
2383 		ap_parse_mask_str(apm_str, ap_perms.apm, AP_DEVICES,
2384 				  &ap_perms_mutex);
2385 	}
2386 
2387 	/* aqm kernel parameter string */
2388 	if (aqm_str) {
2389 		memset(&ap_perms.aqm, 0, sizeof(ap_perms.aqm));
2390 		ap_parse_mask_str(aqm_str, ap_perms.aqm, AP_DOMAINS,
2391 				  &ap_perms_mutex);
2392 	}
2393 }
2394 
2395 /**
2396  * ap_module_init(): The module initialization code.
2397  *
2398  * Initializes the module.
2399  */
2400 static int __init ap_module_init(void)
2401 {
2402 	int rc;
2403 
2404 	rc = ap_debug_init();
2405 	if (rc)
2406 		return rc;
2407 
2408 	if (!ap_instructions_available()) {
2409 		pr_warn("The hardware system does not support AP instructions\n");
2410 		return -ENODEV;
2411 	}
2412 
2413 	/* init ap_queue hashtable */
2414 	hash_init(ap_queues);
2415 
2416 	/* set up the AP permissions (ioctls, ap and aq masks) */
2417 	ap_perms_init();
2418 
2419 	/* Get AP configuration data if available */
2420 	ap_init_qci_info();
2421 
2422 	/* check default domain setting */
2423 	if (ap_domain_index < -1 || ap_domain_index > ap_max_domain_id ||
2424 	    (ap_domain_index >= 0 &&
2425 	     !test_bit_inv(ap_domain_index, ap_perms.aqm))) {
2426 		pr_warn("%d is not a valid cryptographic domain\n",
2427 			ap_domain_index);
2428 		ap_domain_index = -1;
2429 	}
2430 
2431 	/* Create /sys/bus/ap. */
2432 	rc = bus_register(&ap_bus_type);
2433 	if (rc)
2434 		goto out;
2435 
2436 	/* Create /sys/devices/ap. */
2437 	ap_root_device = root_device_register("ap");
2438 	rc = PTR_ERR_OR_ZERO(ap_root_device);
2439 	if (rc)
2440 		goto out_bus;
2441 	ap_root_device->bus = &ap_bus_type;
2442 
2443 	/* enable interrupts if available */
2444 	rc = ap_irq_init();
2445 	if (rc)
2446 		goto out_device;
2447 
2448 	/* Setup asynchronous work (timers, workqueue, etc). */
2449 	rc = ap_async_init();
2450 	if (rc)
2451 		goto out_irq;
2452 
2453 	return 0;
2454 
2455 out_irq:
2456 	ap_irq_exit();
2457 out_device:
2458 	root_device_unregister(ap_root_device);
2459 out_bus:
2460 	bus_unregister(&ap_bus_type);
2461 out:
2462 	ap_debug_exit();
2463 	return rc;
2464 }
2465 
2466 static void __exit ap_module_exit(void)
2467 {
2468 	ap_async_exit();
2469 	ap_irq_exit();
2470 	root_device_unregister(ap_root_device);
2471 	bus_unregister(&ap_bus_type);
2472 	ap_debug_exit();
2473 }
2474 
2475 module_init(ap_module_init);
2476 module_exit(ap_module_exit);
2477