xref: /linux/drivers/s390/crypto/ap_bus.c (revision ba199dc909a20fe62270ae4e93f263987bb9d119)
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, const struct device_driver *drv)
556 {
557 	const 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 				ap_send_bindings_complete_uevent();
736 				pr_debug("%s all apqn bindings complete\n", __func__);
737 			}
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 	/*
898 	 * Rearm the bindings complete completion to trigger
899 	 * bindings complete when all devices are bound again
900 	 */
901 	reinit_completion(&ap_apqn_bindings_complete);
902 
903 	/* Add queue/card to list of active queues/cards */
904 	spin_lock_bh(&ap_queues_lock);
905 	if (is_queue_dev(dev))
906 		hash_add(ap_queues, &to_ap_queue(dev)->hnode,
907 			 to_ap_queue(dev)->qid);
908 	spin_unlock_bh(&ap_queues_lock);
909 
910 	rc = ap_drv->probe ? ap_drv->probe(ap_dev) : -ENODEV;
911 
912 	if (rc) {
913 		spin_lock_bh(&ap_queues_lock);
914 		if (is_queue_dev(dev))
915 			hash_del(&to_ap_queue(dev)->hnode);
916 		spin_unlock_bh(&ap_queues_lock);
917 	}
918 
919 out:
920 	if (rc)
921 		put_device(dev);
922 	return rc;
923 }
924 
925 static void ap_device_remove(struct device *dev)
926 {
927 	struct ap_device *ap_dev = to_ap_dev(dev);
928 	struct ap_driver *ap_drv = to_ap_drv(dev->driver);
929 
930 	/* prepare ap queue device removal */
931 	if (is_queue_dev(dev))
932 		ap_queue_prepare_remove(to_ap_queue(dev));
933 
934 	/* driver's chance to clean up gracefully */
935 	if (ap_drv->remove)
936 		ap_drv->remove(ap_dev);
937 
938 	/* now do the ap queue device remove */
939 	if (is_queue_dev(dev))
940 		ap_queue_remove(to_ap_queue(dev));
941 
942 	/* Remove queue/card from list of active queues/cards */
943 	spin_lock_bh(&ap_queues_lock);
944 	if (is_queue_dev(dev))
945 		hash_del(&to_ap_queue(dev)->hnode);
946 	spin_unlock_bh(&ap_queues_lock);
947 
948 	put_device(dev);
949 }
950 
951 struct ap_queue *ap_get_qdev(ap_qid_t qid)
952 {
953 	int bkt;
954 	struct ap_queue *aq;
955 
956 	spin_lock_bh(&ap_queues_lock);
957 	hash_for_each(ap_queues, bkt, aq, hnode) {
958 		if (aq->qid == qid) {
959 			get_device(&aq->ap_dev.device);
960 			spin_unlock_bh(&ap_queues_lock);
961 			return aq;
962 		}
963 	}
964 	spin_unlock_bh(&ap_queues_lock);
965 
966 	return NULL;
967 }
968 EXPORT_SYMBOL(ap_get_qdev);
969 
970 int ap_driver_register(struct ap_driver *ap_drv, struct module *owner,
971 		       char *name)
972 {
973 	struct device_driver *drv = &ap_drv->driver;
974 
975 	drv->bus = &ap_bus_type;
976 	drv->owner = owner;
977 	drv->name = name;
978 	return driver_register(drv);
979 }
980 EXPORT_SYMBOL(ap_driver_register);
981 
982 void ap_driver_unregister(struct ap_driver *ap_drv)
983 {
984 	driver_unregister(&ap_drv->driver);
985 }
986 EXPORT_SYMBOL(ap_driver_unregister);
987 
988 /*
989  * Enforce a synchronous AP bus rescan.
990  * Returns true if the bus scan finds a change in the AP configuration
991  * and AP devices have been added or deleted when this function returns.
992  */
993 bool ap_bus_force_rescan(void)
994 {
995 	unsigned long scan_counter = atomic64_read(&ap_scan_bus_count);
996 	bool rc = false;
997 
998 	pr_debug(">%s scan counter=%lu\n", __func__, scan_counter);
999 
1000 	/* Only trigger AP bus scans after the initial scan is done */
1001 	if (scan_counter <= 0)
1002 		goto out;
1003 
1004 	/* Try to acquire the AP scan bus mutex */
1005 	if (mutex_trylock(&ap_scan_bus_mutex)) {
1006 		/* mutex acquired, run the AP bus scan */
1007 		ap_scan_bus_result = ap_scan_bus();
1008 		rc = ap_scan_bus_result;
1009 		mutex_unlock(&ap_scan_bus_mutex);
1010 		goto out;
1011 	}
1012 
1013 	/*
1014 	 * Mutex acquire failed. So there is currently another task
1015 	 * already running the AP bus scan. Then let's simple wait
1016 	 * for the lock which means the other task has finished and
1017 	 * stored the result in ap_scan_bus_result.
1018 	 */
1019 	if (mutex_lock_interruptible(&ap_scan_bus_mutex)) {
1020 		/* some error occurred, ignore and go out */
1021 		goto out;
1022 	}
1023 	rc = ap_scan_bus_result;
1024 	mutex_unlock(&ap_scan_bus_mutex);
1025 
1026 out:
1027 	pr_debug("%s rc=%d\n", __func__, rc);
1028 	return rc;
1029 }
1030 EXPORT_SYMBOL(ap_bus_force_rescan);
1031 
1032 /*
1033  * A config change has happened, force an ap bus rescan.
1034  */
1035 static int ap_bus_cfg_chg(struct notifier_block *nb,
1036 			  unsigned long action, void *data)
1037 {
1038 	if (action != CHSC_NOTIFY_AP_CFG)
1039 		return NOTIFY_DONE;
1040 
1041 	pr_debug("%s config change, forcing bus rescan\n", __func__);
1042 
1043 	ap_bus_force_rescan();
1044 
1045 	return NOTIFY_OK;
1046 }
1047 
1048 static struct notifier_block ap_bus_nb = {
1049 	.notifier_call = ap_bus_cfg_chg,
1050 };
1051 
1052 int ap_hex2bitmap(const char *str, unsigned long *bitmap, int bits)
1053 {
1054 	int i, n, b;
1055 
1056 	/* bits needs to be a multiple of 8 */
1057 	if (bits & 0x07)
1058 		return -EINVAL;
1059 
1060 	if (str[0] == '0' && str[1] == 'x')
1061 		str++;
1062 	if (*str == 'x')
1063 		str++;
1064 
1065 	for (i = 0; isxdigit(*str) && i < bits; str++) {
1066 		b = hex_to_bin(*str);
1067 		for (n = 0; n < 4; n++)
1068 			if (b & (0x08 >> n))
1069 				set_bit_inv(i + n, bitmap);
1070 		i += 4;
1071 	}
1072 
1073 	if (*str == '\n')
1074 		str++;
1075 	if (*str)
1076 		return -EINVAL;
1077 	return 0;
1078 }
1079 EXPORT_SYMBOL(ap_hex2bitmap);
1080 
1081 /*
1082  * modify_bitmap() - parse bitmask argument and modify an existing
1083  * bit mask accordingly. A concatenation (done with ',') of these
1084  * terms is recognized:
1085  *   +<bitnr>[-<bitnr>] or -<bitnr>[-<bitnr>]
1086  * <bitnr> may be any valid number (hex, decimal or octal) in the range
1087  * 0...bits-1; the leading + or - is required. Here are some examples:
1088  *   +0-15,+32,-128,-0xFF
1089  *   -0-255,+1-16,+0x128
1090  *   +1,+2,+3,+4,-5,-7-10
1091  * Returns the new bitmap after all changes have been applied. Every
1092  * positive value in the string will set a bit and every negative value
1093  * in the string will clear a bit. As a bit may be touched more than once,
1094  * the last 'operation' wins:
1095  * +0-255,-128 = first bits 0-255 will be set, then bit 128 will be
1096  * cleared again. All other bits are unmodified.
1097  */
1098 static int modify_bitmap(const char *str, unsigned long *bitmap, int bits)
1099 {
1100 	unsigned long a, i, z;
1101 	char *np, sign;
1102 
1103 	/* bits needs to be a multiple of 8 */
1104 	if (bits & 0x07)
1105 		return -EINVAL;
1106 
1107 	while (*str) {
1108 		sign = *str++;
1109 		if (sign != '+' && sign != '-')
1110 			return -EINVAL;
1111 		a = z = simple_strtoul(str, &np, 0);
1112 		if (str == np || a >= bits)
1113 			return -EINVAL;
1114 		str = np;
1115 		if (*str == '-') {
1116 			z = simple_strtoul(++str, &np, 0);
1117 			if (str == np || a > z || z >= bits)
1118 				return -EINVAL;
1119 			str = np;
1120 		}
1121 		for (i = a; i <= z; i++)
1122 			if (sign == '+')
1123 				set_bit_inv(i, bitmap);
1124 			else
1125 				clear_bit_inv(i, bitmap);
1126 		while (*str == ',' || *str == '\n')
1127 			str++;
1128 	}
1129 
1130 	return 0;
1131 }
1132 
1133 static int ap_parse_bitmap_str(const char *str, unsigned long *bitmap, int bits,
1134 			       unsigned long *newmap)
1135 {
1136 	unsigned long size;
1137 	int rc;
1138 
1139 	size = BITS_TO_LONGS(bits) * sizeof(unsigned long);
1140 	if (*str == '+' || *str == '-') {
1141 		memcpy(newmap, bitmap, size);
1142 		rc = modify_bitmap(str, newmap, bits);
1143 	} else {
1144 		memset(newmap, 0, size);
1145 		rc = ap_hex2bitmap(str, newmap, bits);
1146 	}
1147 	return rc;
1148 }
1149 
1150 int ap_parse_mask_str(const char *str,
1151 		      unsigned long *bitmap, int bits,
1152 		      struct mutex *lock)
1153 {
1154 	unsigned long *newmap, size;
1155 	int rc;
1156 
1157 	/* bits needs to be a multiple of 8 */
1158 	if (bits & 0x07)
1159 		return -EINVAL;
1160 
1161 	size = BITS_TO_LONGS(bits) * sizeof(unsigned long);
1162 	newmap = kmalloc(size, GFP_KERNEL);
1163 	if (!newmap)
1164 		return -ENOMEM;
1165 	if (mutex_lock_interruptible(lock)) {
1166 		kfree(newmap);
1167 		return -ERESTARTSYS;
1168 	}
1169 	rc = ap_parse_bitmap_str(str, bitmap, bits, newmap);
1170 	if (rc == 0)
1171 		memcpy(bitmap, newmap, size);
1172 	mutex_unlock(lock);
1173 	kfree(newmap);
1174 	return rc;
1175 }
1176 EXPORT_SYMBOL(ap_parse_mask_str);
1177 
1178 /*
1179  * AP bus attributes.
1180  */
1181 
1182 static ssize_t ap_domain_show(const struct bus_type *bus, char *buf)
1183 {
1184 	return sysfs_emit(buf, "%d\n", ap_domain_index);
1185 }
1186 
1187 static ssize_t ap_domain_store(const struct bus_type *bus,
1188 			       const char *buf, size_t count)
1189 {
1190 	int domain;
1191 
1192 	if (sscanf(buf, "%i\n", &domain) != 1 ||
1193 	    domain < 0 || domain > ap_max_domain_id ||
1194 	    !test_bit_inv(domain, ap_perms.aqm))
1195 		return -EINVAL;
1196 
1197 	spin_lock_bh(&ap_domain_lock);
1198 	ap_domain_index = domain;
1199 	spin_unlock_bh(&ap_domain_lock);
1200 
1201 	AP_DBF_INFO("%s stored new default domain=%d\n",
1202 		    __func__, domain);
1203 
1204 	return count;
1205 }
1206 
1207 static BUS_ATTR_RW(ap_domain);
1208 
1209 static ssize_t ap_control_domain_mask_show(const struct bus_type *bus, char *buf)
1210 {
1211 	if (!ap_qci_info->flags)	/* QCI not supported */
1212 		return sysfs_emit(buf, "not supported\n");
1213 
1214 	return sysfs_emit(buf, "0x%08x%08x%08x%08x%08x%08x%08x%08x\n",
1215 			  ap_qci_info->adm[0], ap_qci_info->adm[1],
1216 			  ap_qci_info->adm[2], ap_qci_info->adm[3],
1217 			  ap_qci_info->adm[4], ap_qci_info->adm[5],
1218 			  ap_qci_info->adm[6], ap_qci_info->adm[7]);
1219 }
1220 
1221 static BUS_ATTR_RO(ap_control_domain_mask);
1222 
1223 static ssize_t ap_usage_domain_mask_show(const struct bus_type *bus, char *buf)
1224 {
1225 	if (!ap_qci_info->flags)	/* QCI not supported */
1226 		return sysfs_emit(buf, "not supported\n");
1227 
1228 	return sysfs_emit(buf, "0x%08x%08x%08x%08x%08x%08x%08x%08x\n",
1229 			  ap_qci_info->aqm[0], ap_qci_info->aqm[1],
1230 			  ap_qci_info->aqm[2], ap_qci_info->aqm[3],
1231 			  ap_qci_info->aqm[4], ap_qci_info->aqm[5],
1232 			  ap_qci_info->aqm[6], ap_qci_info->aqm[7]);
1233 }
1234 
1235 static BUS_ATTR_RO(ap_usage_domain_mask);
1236 
1237 static ssize_t ap_adapter_mask_show(const struct bus_type *bus, char *buf)
1238 {
1239 	if (!ap_qci_info->flags)	/* QCI not supported */
1240 		return sysfs_emit(buf, "not supported\n");
1241 
1242 	return sysfs_emit(buf, "0x%08x%08x%08x%08x%08x%08x%08x%08x\n",
1243 			  ap_qci_info->apm[0], ap_qci_info->apm[1],
1244 			  ap_qci_info->apm[2], ap_qci_info->apm[3],
1245 			  ap_qci_info->apm[4], ap_qci_info->apm[5],
1246 			  ap_qci_info->apm[6], ap_qci_info->apm[7]);
1247 }
1248 
1249 static BUS_ATTR_RO(ap_adapter_mask);
1250 
1251 static ssize_t ap_interrupts_show(const struct bus_type *bus, char *buf)
1252 {
1253 	return sysfs_emit(buf, "%d\n", ap_irq_flag ? 1 : 0);
1254 }
1255 
1256 static BUS_ATTR_RO(ap_interrupts);
1257 
1258 static ssize_t config_time_show(const struct bus_type *bus, char *buf)
1259 {
1260 	return sysfs_emit(buf, "%d\n", ap_scan_bus_time);
1261 }
1262 
1263 static ssize_t config_time_store(const struct bus_type *bus,
1264 				 const char *buf, size_t count)
1265 {
1266 	int time;
1267 
1268 	if (sscanf(buf, "%d\n", &time) != 1 || time < 5 || time > 120)
1269 		return -EINVAL;
1270 	ap_scan_bus_time = time;
1271 	mod_timer(&ap_scan_bus_timer, jiffies + ap_scan_bus_time * HZ);
1272 	return count;
1273 }
1274 
1275 static BUS_ATTR_RW(config_time);
1276 
1277 static ssize_t poll_thread_show(const struct bus_type *bus, char *buf)
1278 {
1279 	return sysfs_emit(buf, "%d\n", ap_poll_kthread ? 1 : 0);
1280 }
1281 
1282 static ssize_t poll_thread_store(const struct bus_type *bus,
1283 				 const char *buf, size_t count)
1284 {
1285 	bool value;
1286 	int rc;
1287 
1288 	rc = kstrtobool(buf, &value);
1289 	if (rc)
1290 		return rc;
1291 
1292 	if (value) {
1293 		rc = ap_poll_thread_start();
1294 		if (rc)
1295 			count = rc;
1296 	} else {
1297 		ap_poll_thread_stop();
1298 	}
1299 	return count;
1300 }
1301 
1302 static BUS_ATTR_RW(poll_thread);
1303 
1304 static ssize_t poll_timeout_show(const struct bus_type *bus, char *buf)
1305 {
1306 	return sysfs_emit(buf, "%lu\n", poll_high_timeout);
1307 }
1308 
1309 static ssize_t poll_timeout_store(const struct bus_type *bus, const char *buf,
1310 				  size_t count)
1311 {
1312 	unsigned long value;
1313 	ktime_t hr_time;
1314 	int rc;
1315 
1316 	rc = kstrtoul(buf, 0, &value);
1317 	if (rc)
1318 		return rc;
1319 
1320 	/* 120 seconds = maximum poll interval */
1321 	if (value > 120000000000UL)
1322 		return -EINVAL;
1323 	poll_high_timeout = value;
1324 	hr_time = poll_high_timeout;
1325 
1326 	spin_lock_bh(&ap_poll_timer_lock);
1327 	hrtimer_cancel(&ap_poll_timer);
1328 	hrtimer_set_expires(&ap_poll_timer, hr_time);
1329 	hrtimer_start_expires(&ap_poll_timer, HRTIMER_MODE_ABS);
1330 	spin_unlock_bh(&ap_poll_timer_lock);
1331 
1332 	return count;
1333 }
1334 
1335 static BUS_ATTR_RW(poll_timeout);
1336 
1337 static ssize_t ap_max_domain_id_show(const struct bus_type *bus, char *buf)
1338 {
1339 	return sysfs_emit(buf, "%d\n", ap_max_domain_id);
1340 }
1341 
1342 static BUS_ATTR_RO(ap_max_domain_id);
1343 
1344 static ssize_t ap_max_adapter_id_show(const struct bus_type *bus, char *buf)
1345 {
1346 	return sysfs_emit(buf, "%d\n", ap_max_adapter_id);
1347 }
1348 
1349 static BUS_ATTR_RO(ap_max_adapter_id);
1350 
1351 static ssize_t apmask_show(const struct bus_type *bus, char *buf)
1352 {
1353 	int rc;
1354 
1355 	if (mutex_lock_interruptible(&ap_perms_mutex))
1356 		return -ERESTARTSYS;
1357 	rc = sysfs_emit(buf, "0x%016lx%016lx%016lx%016lx\n",
1358 			ap_perms.apm[0], ap_perms.apm[1],
1359 			ap_perms.apm[2], ap_perms.apm[3]);
1360 	mutex_unlock(&ap_perms_mutex);
1361 
1362 	return rc;
1363 }
1364 
1365 static int __verify_card_reservations(struct device_driver *drv, void *data)
1366 {
1367 	int rc = 0;
1368 	struct ap_driver *ap_drv = to_ap_drv(drv);
1369 	unsigned long *newapm = (unsigned long *)data;
1370 
1371 	/*
1372 	 * increase the driver's module refcounter to be sure it is not
1373 	 * going away when we invoke the callback function.
1374 	 */
1375 	if (!try_module_get(drv->owner))
1376 		return 0;
1377 
1378 	if (ap_drv->in_use) {
1379 		rc = ap_drv->in_use(newapm, ap_perms.aqm);
1380 		if (rc)
1381 			rc = -EBUSY;
1382 	}
1383 
1384 	/* release the driver's module */
1385 	module_put(drv->owner);
1386 
1387 	return rc;
1388 }
1389 
1390 static int apmask_commit(unsigned long *newapm)
1391 {
1392 	int rc;
1393 	unsigned long reserved[BITS_TO_LONGS(AP_DEVICES)];
1394 
1395 	/*
1396 	 * Check if any bits in the apmask have been set which will
1397 	 * result in queues being removed from non-default drivers
1398 	 */
1399 	if (bitmap_andnot(reserved, newapm, ap_perms.apm, AP_DEVICES)) {
1400 		rc = bus_for_each_drv(&ap_bus_type, NULL, reserved,
1401 				      __verify_card_reservations);
1402 		if (rc)
1403 			return rc;
1404 	}
1405 
1406 	memcpy(ap_perms.apm, newapm, APMASKSIZE);
1407 
1408 	return 0;
1409 }
1410 
1411 static ssize_t apmask_store(const struct bus_type *bus, const char *buf,
1412 			    size_t count)
1413 {
1414 	int rc, changes = 0;
1415 	DECLARE_BITMAP(newapm, AP_DEVICES);
1416 
1417 	if (mutex_lock_interruptible(&ap_perms_mutex))
1418 		return -ERESTARTSYS;
1419 
1420 	rc = ap_parse_bitmap_str(buf, ap_perms.apm, AP_DEVICES, newapm);
1421 	if (rc)
1422 		goto done;
1423 
1424 	changes = memcmp(ap_perms.apm, newapm, APMASKSIZE);
1425 	if (changes)
1426 		rc = apmask_commit(newapm);
1427 
1428 done:
1429 	mutex_unlock(&ap_perms_mutex);
1430 	if (rc)
1431 		return rc;
1432 
1433 	if (changes) {
1434 		ap_bus_revise_bindings();
1435 		ap_send_mask_changed_uevent(newapm, NULL);
1436 	}
1437 
1438 	return count;
1439 }
1440 
1441 static BUS_ATTR_RW(apmask);
1442 
1443 static ssize_t aqmask_show(const struct bus_type *bus, char *buf)
1444 {
1445 	int rc;
1446 
1447 	if (mutex_lock_interruptible(&ap_perms_mutex))
1448 		return -ERESTARTSYS;
1449 	rc = sysfs_emit(buf, "0x%016lx%016lx%016lx%016lx\n",
1450 			ap_perms.aqm[0], ap_perms.aqm[1],
1451 			ap_perms.aqm[2], ap_perms.aqm[3]);
1452 	mutex_unlock(&ap_perms_mutex);
1453 
1454 	return rc;
1455 }
1456 
1457 static int __verify_queue_reservations(struct device_driver *drv, void *data)
1458 {
1459 	int rc = 0;
1460 	struct ap_driver *ap_drv = to_ap_drv(drv);
1461 	unsigned long *newaqm = (unsigned long *)data;
1462 
1463 	/*
1464 	 * increase the driver's module refcounter to be sure it is not
1465 	 * going away when we invoke the callback function.
1466 	 */
1467 	if (!try_module_get(drv->owner))
1468 		return 0;
1469 
1470 	if (ap_drv->in_use) {
1471 		rc = ap_drv->in_use(ap_perms.apm, newaqm);
1472 		if (rc)
1473 			rc = -EBUSY;
1474 	}
1475 
1476 	/* release the driver's module */
1477 	module_put(drv->owner);
1478 
1479 	return rc;
1480 }
1481 
1482 static int aqmask_commit(unsigned long *newaqm)
1483 {
1484 	int rc;
1485 	unsigned long reserved[BITS_TO_LONGS(AP_DOMAINS)];
1486 
1487 	/*
1488 	 * Check if any bits in the aqmask have been set which will
1489 	 * result in queues being removed from non-default drivers
1490 	 */
1491 	if (bitmap_andnot(reserved, newaqm, ap_perms.aqm, AP_DOMAINS)) {
1492 		rc = bus_for_each_drv(&ap_bus_type, NULL, reserved,
1493 				      __verify_queue_reservations);
1494 		if (rc)
1495 			return rc;
1496 	}
1497 
1498 	memcpy(ap_perms.aqm, newaqm, AQMASKSIZE);
1499 
1500 	return 0;
1501 }
1502 
1503 static ssize_t aqmask_store(const struct bus_type *bus, const char *buf,
1504 			    size_t count)
1505 {
1506 	int rc, changes = 0;
1507 	DECLARE_BITMAP(newaqm, AP_DOMAINS);
1508 
1509 	if (mutex_lock_interruptible(&ap_perms_mutex))
1510 		return -ERESTARTSYS;
1511 
1512 	rc = ap_parse_bitmap_str(buf, ap_perms.aqm, AP_DOMAINS, newaqm);
1513 	if (rc)
1514 		goto done;
1515 
1516 	changes = memcmp(ap_perms.aqm, newaqm, APMASKSIZE);
1517 	if (changes)
1518 		rc = aqmask_commit(newaqm);
1519 
1520 done:
1521 	mutex_unlock(&ap_perms_mutex);
1522 	if (rc)
1523 		return rc;
1524 
1525 	if (changes) {
1526 		ap_bus_revise_bindings();
1527 		ap_send_mask_changed_uevent(NULL, newaqm);
1528 	}
1529 
1530 	return count;
1531 }
1532 
1533 static BUS_ATTR_RW(aqmask);
1534 
1535 static ssize_t scans_show(const struct bus_type *bus, char *buf)
1536 {
1537 	return sysfs_emit(buf, "%llu\n", atomic64_read(&ap_scan_bus_count));
1538 }
1539 
1540 static ssize_t scans_store(const struct bus_type *bus, const char *buf,
1541 			   size_t count)
1542 {
1543 	AP_DBF_INFO("%s force AP bus rescan\n", __func__);
1544 
1545 	ap_bus_force_rescan();
1546 
1547 	return count;
1548 }
1549 
1550 static BUS_ATTR_RW(scans);
1551 
1552 static ssize_t bindings_show(const struct bus_type *bus, char *buf)
1553 {
1554 	int rc;
1555 	unsigned int apqns, n;
1556 
1557 	ap_calc_bound_apqns(&apqns, &n);
1558 	if (atomic64_read(&ap_scan_bus_count) >= 1 && n == apqns)
1559 		rc = sysfs_emit(buf, "%u/%u (complete)\n", n, apqns);
1560 	else
1561 		rc = sysfs_emit(buf, "%u/%u\n", n, apqns);
1562 
1563 	return rc;
1564 }
1565 
1566 static BUS_ATTR_RO(bindings);
1567 
1568 static ssize_t features_show(const struct bus_type *bus, char *buf)
1569 {
1570 	int n = 0;
1571 
1572 	if (!ap_qci_info->flags)	/* QCI not supported */
1573 		return sysfs_emit(buf, "-\n");
1574 
1575 	if (ap_qci_info->apsc)
1576 		n += sysfs_emit_at(buf, n, "APSC ");
1577 	if (ap_qci_info->apxa)
1578 		n += sysfs_emit_at(buf, n, "APXA ");
1579 	if (ap_qci_info->qact)
1580 		n += sysfs_emit_at(buf, n, "QACT ");
1581 	if (ap_qci_info->rc8a)
1582 		n += sysfs_emit_at(buf, n, "RC8A ");
1583 	if (ap_qci_info->apsb)
1584 		n += sysfs_emit_at(buf, n, "APSB ");
1585 
1586 	sysfs_emit_at(buf, n == 0 ? 0 : n - 1, "\n");
1587 
1588 	return n;
1589 }
1590 
1591 static BUS_ATTR_RO(features);
1592 
1593 static struct attribute *ap_bus_attrs[] = {
1594 	&bus_attr_ap_domain.attr,
1595 	&bus_attr_ap_control_domain_mask.attr,
1596 	&bus_attr_ap_usage_domain_mask.attr,
1597 	&bus_attr_ap_adapter_mask.attr,
1598 	&bus_attr_config_time.attr,
1599 	&bus_attr_poll_thread.attr,
1600 	&bus_attr_ap_interrupts.attr,
1601 	&bus_attr_poll_timeout.attr,
1602 	&bus_attr_ap_max_domain_id.attr,
1603 	&bus_attr_ap_max_adapter_id.attr,
1604 	&bus_attr_apmask.attr,
1605 	&bus_attr_aqmask.attr,
1606 	&bus_attr_scans.attr,
1607 	&bus_attr_bindings.attr,
1608 	&bus_attr_features.attr,
1609 	NULL,
1610 };
1611 ATTRIBUTE_GROUPS(ap_bus);
1612 
1613 static const struct bus_type ap_bus_type = {
1614 	.name = "ap",
1615 	.bus_groups = ap_bus_groups,
1616 	.match = &ap_bus_match,
1617 	.uevent = &ap_uevent,
1618 	.probe = ap_device_probe,
1619 	.remove = ap_device_remove,
1620 };
1621 
1622 /**
1623  * ap_select_domain(): Select an AP domain if possible and we haven't
1624  * already done so before.
1625  */
1626 static void ap_select_domain(void)
1627 {
1628 	struct ap_queue_status status;
1629 	int card, dom;
1630 
1631 	/*
1632 	 * Choose the default domain. Either the one specified with
1633 	 * the "domain=" parameter or the first domain with at least
1634 	 * one valid APQN.
1635 	 */
1636 	spin_lock_bh(&ap_domain_lock);
1637 	if (ap_domain_index >= 0) {
1638 		/* Domain has already been selected. */
1639 		goto out;
1640 	}
1641 	for (dom = 0; dom <= ap_max_domain_id; dom++) {
1642 		if (!ap_test_config_usage_domain(dom) ||
1643 		    !test_bit_inv(dom, ap_perms.aqm))
1644 			continue;
1645 		for (card = 0; card <= ap_max_adapter_id; card++) {
1646 			if (!ap_test_config_card_id(card) ||
1647 			    !test_bit_inv(card, ap_perms.apm))
1648 				continue;
1649 			status = ap_test_queue(AP_MKQID(card, dom),
1650 					       ap_apft_available(),
1651 					       NULL);
1652 			if (status.response_code == AP_RESPONSE_NORMAL)
1653 				break;
1654 		}
1655 		if (card <= ap_max_adapter_id)
1656 			break;
1657 	}
1658 	if (dom <= ap_max_domain_id) {
1659 		ap_domain_index = dom;
1660 		AP_DBF_INFO("%s new default domain is %d\n",
1661 			    __func__, ap_domain_index);
1662 	}
1663 out:
1664 	spin_unlock_bh(&ap_domain_lock);
1665 }
1666 
1667 /*
1668  * This function checks the type and returns either 0 for not
1669  * supported or the highest compatible type value (which may
1670  * include the input type value).
1671  */
1672 static int ap_get_compatible_type(ap_qid_t qid, int rawtype, unsigned int func)
1673 {
1674 	int comp_type = 0;
1675 
1676 	/* < CEX4 is not supported */
1677 	if (rawtype < AP_DEVICE_TYPE_CEX4) {
1678 		AP_DBF_WARN("%s queue=%02x.%04x unsupported type %d\n",
1679 			    __func__, AP_QID_CARD(qid),
1680 			    AP_QID_QUEUE(qid), rawtype);
1681 		return 0;
1682 	}
1683 	/* up to CEX8 known and fully supported */
1684 	if (rawtype <= AP_DEVICE_TYPE_CEX8)
1685 		return rawtype;
1686 	/*
1687 	 * unknown new type > CEX8, check for compatibility
1688 	 * to the highest known and supported type which is
1689 	 * currently CEX8 with the help of the QACT function.
1690 	 */
1691 	if (ap_qact_available()) {
1692 		struct ap_queue_status status;
1693 		union ap_qact_ap_info apinfo = {0};
1694 
1695 		apinfo.mode = (func >> 26) & 0x07;
1696 		apinfo.cat = AP_DEVICE_TYPE_CEX8;
1697 		status = ap_qact(qid, 0, &apinfo);
1698 		if (status.response_code == AP_RESPONSE_NORMAL &&
1699 		    apinfo.cat >= AP_DEVICE_TYPE_CEX4 &&
1700 		    apinfo.cat <= AP_DEVICE_TYPE_CEX8)
1701 			comp_type = apinfo.cat;
1702 	}
1703 	if (!comp_type)
1704 		AP_DBF_WARN("%s queue=%02x.%04x unable to map type %d\n",
1705 			    __func__, AP_QID_CARD(qid),
1706 			    AP_QID_QUEUE(qid), rawtype);
1707 	else if (comp_type != rawtype)
1708 		AP_DBF_INFO("%s queue=%02x.%04x map type %d to %d\n",
1709 			    __func__, AP_QID_CARD(qid), AP_QID_QUEUE(qid),
1710 			    rawtype, comp_type);
1711 	return comp_type;
1712 }
1713 
1714 /*
1715  * Helper function to be used with bus_find_dev
1716  * matches for the card device with the given id
1717  */
1718 static int __match_card_device_with_id(struct device *dev, const void *data)
1719 {
1720 	return is_card_dev(dev) && to_ap_card(dev)->id == (int)(long)(void *)data;
1721 }
1722 
1723 /*
1724  * Helper function to be used with bus_find_dev
1725  * matches for the queue device with a given qid
1726  */
1727 static int __match_queue_device_with_qid(struct device *dev, const void *data)
1728 {
1729 	return is_queue_dev(dev) && to_ap_queue(dev)->qid == (int)(long)data;
1730 }
1731 
1732 /*
1733  * Helper function to be used with bus_find_dev
1734  * matches any queue device with given queue id
1735  */
1736 static int __match_queue_device_with_queue_id(struct device *dev, const void *data)
1737 {
1738 	return is_queue_dev(dev) &&
1739 		AP_QID_QUEUE(to_ap_queue(dev)->qid) == (int)(long)data;
1740 }
1741 
1742 /* Helper function for notify_config_changed */
1743 static int __drv_notify_config_changed(struct device_driver *drv, void *data)
1744 {
1745 	struct ap_driver *ap_drv = to_ap_drv(drv);
1746 
1747 	if (try_module_get(drv->owner)) {
1748 		if (ap_drv->on_config_changed)
1749 			ap_drv->on_config_changed(ap_qci_info, ap_qci_info_old);
1750 		module_put(drv->owner);
1751 	}
1752 
1753 	return 0;
1754 }
1755 
1756 /* Notify all drivers about an qci config change */
1757 static inline void notify_config_changed(void)
1758 {
1759 	bus_for_each_drv(&ap_bus_type, NULL, NULL,
1760 			 __drv_notify_config_changed);
1761 }
1762 
1763 /* Helper function for notify_scan_complete */
1764 static int __drv_notify_scan_complete(struct device_driver *drv, void *data)
1765 {
1766 	struct ap_driver *ap_drv = to_ap_drv(drv);
1767 
1768 	if (try_module_get(drv->owner)) {
1769 		if (ap_drv->on_scan_complete)
1770 			ap_drv->on_scan_complete(ap_qci_info,
1771 						 ap_qci_info_old);
1772 		module_put(drv->owner);
1773 	}
1774 
1775 	return 0;
1776 }
1777 
1778 /* Notify all drivers about bus scan complete */
1779 static inline void notify_scan_complete(void)
1780 {
1781 	bus_for_each_drv(&ap_bus_type, NULL, NULL,
1782 			 __drv_notify_scan_complete);
1783 }
1784 
1785 /*
1786  * Helper function for ap_scan_bus().
1787  * Remove card device and associated queue devices.
1788  */
1789 static inline void ap_scan_rm_card_dev_and_queue_devs(struct ap_card *ac)
1790 {
1791 	bus_for_each_dev(&ap_bus_type, NULL,
1792 			 (void *)(long)ac->id,
1793 			 __ap_queue_devices_with_id_unregister);
1794 	device_unregister(&ac->ap_dev.device);
1795 }
1796 
1797 /*
1798  * Helper function for ap_scan_bus().
1799  * Does the scan bus job for all the domains within
1800  * a valid adapter given by an ap_card ptr.
1801  */
1802 static inline void ap_scan_domains(struct ap_card *ac)
1803 {
1804 	struct ap_tapq_hwinfo hwinfo;
1805 	bool decfg, chkstop;
1806 	struct ap_queue *aq;
1807 	struct device *dev;
1808 	ap_qid_t qid;
1809 	int rc, dom;
1810 
1811 	/*
1812 	 * Go through the configuration for the domains and compare them
1813 	 * to the existing queue devices. Also take care of the config
1814 	 * and error state for the queue devices.
1815 	 */
1816 
1817 	for (dom = 0; dom <= ap_max_domain_id; dom++) {
1818 		qid = AP_MKQID(ac->id, dom);
1819 		dev = bus_find_device(&ap_bus_type, NULL,
1820 				      (void *)(long)qid,
1821 				      __match_queue_device_with_qid);
1822 		aq = dev ? to_ap_queue(dev) : NULL;
1823 		if (!ap_test_config_usage_domain(dom)) {
1824 			if (dev) {
1825 				AP_DBF_INFO("%s(%d,%d) not in config anymore, rm queue dev\n",
1826 					    __func__, ac->id, dom);
1827 				device_unregister(dev);
1828 			}
1829 			goto put_dev_and_continue;
1830 		}
1831 		/* domain is valid, get info from this APQN */
1832 		rc = ap_queue_info(qid, &hwinfo, &decfg, &chkstop);
1833 		switch (rc) {
1834 		case -1:
1835 			if (dev) {
1836 				AP_DBF_INFO("%s(%d,%d) queue_info() failed, rm queue dev\n",
1837 					    __func__, ac->id, dom);
1838 				device_unregister(dev);
1839 			}
1840 			fallthrough;
1841 		case 0:
1842 			goto put_dev_and_continue;
1843 		default:
1844 			break;
1845 		}
1846 		/* if no queue device exists, create a new one */
1847 		if (!aq) {
1848 			aq = ap_queue_create(qid, ac->ap_dev.device_type);
1849 			if (!aq) {
1850 				AP_DBF_WARN("%s(%d,%d) ap_queue_create() failed\n",
1851 					    __func__, ac->id, dom);
1852 				continue;
1853 			}
1854 			aq->card = ac;
1855 			aq->config = !decfg;
1856 			aq->chkstop = chkstop;
1857 			aq->se_bstate = hwinfo.bs;
1858 			dev = &aq->ap_dev.device;
1859 			dev->bus = &ap_bus_type;
1860 			dev->parent = &ac->ap_dev.device;
1861 			dev_set_name(dev, "%02x.%04x", ac->id, dom);
1862 			/* register queue device */
1863 			rc = device_register(dev);
1864 			if (rc) {
1865 				AP_DBF_WARN("%s(%d,%d) device_register() failed\n",
1866 					    __func__, ac->id, dom);
1867 				goto put_dev_and_continue;
1868 			}
1869 			/* get it and thus adjust reference counter */
1870 			get_device(dev);
1871 			if (decfg) {
1872 				AP_DBF_INFO("%s(%d,%d) new (decfg) queue dev created\n",
1873 					    __func__, ac->id, dom);
1874 			} else if (chkstop) {
1875 				AP_DBF_INFO("%s(%d,%d) new (chkstop) queue dev created\n",
1876 					    __func__, ac->id, dom);
1877 			} else {
1878 				/* nudge the queue's state machine */
1879 				ap_queue_init_state(aq);
1880 				AP_DBF_INFO("%s(%d,%d) new queue dev created\n",
1881 					    __func__, ac->id, dom);
1882 			}
1883 			goto put_dev_and_continue;
1884 		}
1885 		/* handle state changes on already existing queue device */
1886 		spin_lock_bh(&aq->lock);
1887 		/* SE bind state */
1888 		aq->se_bstate = hwinfo.bs;
1889 		/* checkstop state */
1890 		if (chkstop && !aq->chkstop) {
1891 			/* checkstop on */
1892 			aq->chkstop = true;
1893 			if (aq->dev_state > AP_DEV_STATE_UNINITIATED) {
1894 				aq->dev_state = AP_DEV_STATE_ERROR;
1895 				aq->last_err_rc = AP_RESPONSE_CHECKSTOPPED;
1896 			}
1897 			spin_unlock_bh(&aq->lock);
1898 			pr_debug("%s(%d,%d) queue dev checkstop on\n",
1899 				 __func__, ac->id, dom);
1900 			/* 'receive' pending messages with -EAGAIN */
1901 			ap_flush_queue(aq);
1902 			goto put_dev_and_continue;
1903 		} else if (!chkstop && aq->chkstop) {
1904 			/* checkstop off */
1905 			aq->chkstop = false;
1906 			if (aq->dev_state > AP_DEV_STATE_UNINITIATED)
1907 				_ap_queue_init_state(aq);
1908 			spin_unlock_bh(&aq->lock);
1909 			pr_debug("%s(%d,%d) queue dev checkstop off\n",
1910 				 __func__, ac->id, dom);
1911 			goto put_dev_and_continue;
1912 		}
1913 		/* config state change */
1914 		if (decfg && aq->config) {
1915 			/* config off this queue device */
1916 			aq->config = false;
1917 			if (aq->dev_state > AP_DEV_STATE_UNINITIATED) {
1918 				aq->dev_state = AP_DEV_STATE_ERROR;
1919 				aq->last_err_rc = AP_RESPONSE_DECONFIGURED;
1920 			}
1921 			spin_unlock_bh(&aq->lock);
1922 			pr_debug("%s(%d,%d) queue dev config off\n",
1923 				 __func__, ac->id, dom);
1924 			ap_send_config_uevent(&aq->ap_dev, aq->config);
1925 			/* 'receive' pending messages with -EAGAIN */
1926 			ap_flush_queue(aq);
1927 			goto put_dev_and_continue;
1928 		} else if (!decfg && !aq->config) {
1929 			/* config on this queue device */
1930 			aq->config = true;
1931 			if (aq->dev_state > AP_DEV_STATE_UNINITIATED)
1932 				_ap_queue_init_state(aq);
1933 			spin_unlock_bh(&aq->lock);
1934 			pr_debug("%s(%d,%d) queue dev config on\n",
1935 				 __func__, ac->id, dom);
1936 			ap_send_config_uevent(&aq->ap_dev, aq->config);
1937 			goto put_dev_and_continue;
1938 		}
1939 		/* handle other error states */
1940 		if (!decfg && aq->dev_state == AP_DEV_STATE_ERROR) {
1941 			spin_unlock_bh(&aq->lock);
1942 			/* 'receive' pending messages with -EAGAIN */
1943 			ap_flush_queue(aq);
1944 			/* re-init (with reset) the queue device */
1945 			ap_queue_init_state(aq);
1946 			AP_DBF_INFO("%s(%d,%d) queue dev reinit enforced\n",
1947 				    __func__, ac->id, dom);
1948 			goto put_dev_and_continue;
1949 		}
1950 		spin_unlock_bh(&aq->lock);
1951 put_dev_and_continue:
1952 		put_device(dev);
1953 	}
1954 }
1955 
1956 /*
1957  * Helper function for ap_scan_bus().
1958  * Does the scan bus job for the given adapter id.
1959  */
1960 static inline void ap_scan_adapter(int ap)
1961 {
1962 	struct ap_tapq_hwinfo hwinfo;
1963 	int rc, dom, comp_type;
1964 	bool decfg, chkstop;
1965 	struct ap_card *ac;
1966 	struct device *dev;
1967 	ap_qid_t qid;
1968 
1969 	/* Is there currently a card device for this adapter ? */
1970 	dev = bus_find_device(&ap_bus_type, NULL,
1971 			      (void *)(long)ap,
1972 			      __match_card_device_with_id);
1973 	ac = dev ? to_ap_card(dev) : NULL;
1974 
1975 	/* Adapter not in configuration ? */
1976 	if (!ap_test_config_card_id(ap)) {
1977 		if (ac) {
1978 			AP_DBF_INFO("%s(%d) ap not in config any more, rm card and queue devs\n",
1979 				    __func__, ap);
1980 			ap_scan_rm_card_dev_and_queue_devs(ac);
1981 			put_device(dev);
1982 		}
1983 		return;
1984 	}
1985 
1986 	/*
1987 	 * Adapter ap is valid in the current configuration. So do some checks:
1988 	 * If no card device exists, build one. If a card device exists, check
1989 	 * for type and functions changed. For all this we need to find a valid
1990 	 * APQN first.
1991 	 */
1992 
1993 	for (dom = 0; dom <= ap_max_domain_id; dom++)
1994 		if (ap_test_config_usage_domain(dom)) {
1995 			qid = AP_MKQID(ap, dom);
1996 			if (ap_queue_info(qid, &hwinfo, &decfg, &chkstop) > 0)
1997 				break;
1998 		}
1999 	if (dom > ap_max_domain_id) {
2000 		/* Could not find one valid APQN for this adapter */
2001 		if (ac) {
2002 			AP_DBF_INFO("%s(%d) no type info (no APQN found), rm card and queue devs\n",
2003 				    __func__, ap);
2004 			ap_scan_rm_card_dev_and_queue_devs(ac);
2005 			put_device(dev);
2006 		} else {
2007 			pr_debug("%s(%d) no type info (no APQN found), ignored\n",
2008 				 __func__, ap);
2009 		}
2010 		return;
2011 	}
2012 	if (!hwinfo.at) {
2013 		/* No apdater type info available, an unusable adapter */
2014 		if (ac) {
2015 			AP_DBF_INFO("%s(%d) no valid type (0) info, rm card and queue devs\n",
2016 				    __func__, ap);
2017 			ap_scan_rm_card_dev_and_queue_devs(ac);
2018 			put_device(dev);
2019 		} else {
2020 			pr_debug("%s(%d) no valid type (0) info, ignored\n",
2021 				 __func__, ap);
2022 		}
2023 		return;
2024 	}
2025 	hwinfo.value &= TAPQ_CARD_HWINFO_MASK; /* filter card specific hwinfo */
2026 	if (ac) {
2027 		/* Check APQN against existing card device for changes */
2028 		if (ac->hwinfo.at != hwinfo.at) {
2029 			AP_DBF_INFO("%s(%d) hwtype %d changed, rm card and queue devs\n",
2030 				    __func__, ap, hwinfo.at);
2031 			ap_scan_rm_card_dev_and_queue_devs(ac);
2032 			put_device(dev);
2033 			ac = NULL;
2034 		} else if (ac->hwinfo.fac != hwinfo.fac) {
2035 			AP_DBF_INFO("%s(%d) functions 0x%08x changed, rm card and queue devs\n",
2036 				    __func__, ap, hwinfo.fac);
2037 			ap_scan_rm_card_dev_and_queue_devs(ac);
2038 			put_device(dev);
2039 			ac = NULL;
2040 		} else {
2041 			/* handle checkstop state change */
2042 			if (chkstop && !ac->chkstop) {
2043 				/* checkstop on */
2044 				ac->chkstop = true;
2045 				AP_DBF_INFO("%s(%d) card dev checkstop on\n",
2046 					    __func__, ap);
2047 			} else if (!chkstop && ac->chkstop) {
2048 				/* checkstop off */
2049 				ac->chkstop = false;
2050 				AP_DBF_INFO("%s(%d) card dev checkstop off\n",
2051 					    __func__, ap);
2052 			}
2053 			/* handle config state change */
2054 			if (decfg && ac->config) {
2055 				ac->config = false;
2056 				AP_DBF_INFO("%s(%d) card dev config off\n",
2057 					    __func__, ap);
2058 				ap_send_config_uevent(&ac->ap_dev, ac->config);
2059 			} else if (!decfg && !ac->config) {
2060 				ac->config = true;
2061 				AP_DBF_INFO("%s(%d) card dev config on\n",
2062 					    __func__, ap);
2063 				ap_send_config_uevent(&ac->ap_dev, ac->config);
2064 			}
2065 		}
2066 	}
2067 
2068 	if (!ac) {
2069 		/* Build a new card device */
2070 		comp_type = ap_get_compatible_type(qid, hwinfo.at, hwinfo.fac);
2071 		if (!comp_type) {
2072 			AP_DBF_WARN("%s(%d) type %d, can't get compatibility type\n",
2073 				    __func__, ap, hwinfo.at);
2074 			return;
2075 		}
2076 		ac = ap_card_create(ap, hwinfo, comp_type);
2077 		if (!ac) {
2078 			AP_DBF_WARN("%s(%d) ap_card_create() failed\n",
2079 				    __func__, ap);
2080 			return;
2081 		}
2082 		ac->config = !decfg;
2083 		ac->chkstop = chkstop;
2084 		dev = &ac->ap_dev.device;
2085 		dev->bus = &ap_bus_type;
2086 		dev->parent = ap_root_device;
2087 		dev_set_name(dev, "card%02x", ap);
2088 		/* maybe enlarge ap_max_msg_size to support this card */
2089 		if (ac->maxmsgsize > atomic_read(&ap_max_msg_size)) {
2090 			atomic_set(&ap_max_msg_size, ac->maxmsgsize);
2091 			AP_DBF_INFO("%s(%d) ap_max_msg_size update to %d byte\n",
2092 				    __func__, ap,
2093 				    atomic_read(&ap_max_msg_size));
2094 		}
2095 		/* Register the new card device with AP bus */
2096 		rc = device_register(dev);
2097 		if (rc) {
2098 			AP_DBF_WARN("%s(%d) device_register() failed\n",
2099 				    __func__, ap);
2100 			put_device(dev);
2101 			return;
2102 		}
2103 		/* get it and thus adjust reference counter */
2104 		get_device(dev);
2105 		if (decfg)
2106 			AP_DBF_INFO("%s(%d) new (decfg) card dev type=%d func=0x%08x created\n",
2107 				    __func__, ap, hwinfo.at, hwinfo.fac);
2108 		else if (chkstop)
2109 			AP_DBF_INFO("%s(%d) new (chkstop) card dev type=%d func=0x%08x created\n",
2110 				    __func__, ap, hwinfo.at, hwinfo.fac);
2111 		else
2112 			AP_DBF_INFO("%s(%d) new card dev type=%d func=0x%08x created\n",
2113 				    __func__, ap, hwinfo.at, hwinfo.fac);
2114 	}
2115 
2116 	/* Verify the domains and the queue devices for this card */
2117 	ap_scan_domains(ac);
2118 
2119 	/* release the card device */
2120 	put_device(&ac->ap_dev.device);
2121 }
2122 
2123 /**
2124  * ap_get_configuration - get the host AP configuration
2125  *
2126  * Stores the host AP configuration information returned from the previous call
2127  * to Query Configuration Information (QCI), then retrieves and stores the
2128  * current AP configuration returned from QCI.
2129  *
2130  * Return: true if the host AP configuration changed between calls to QCI;
2131  * otherwise, return false.
2132  */
2133 static bool ap_get_configuration(void)
2134 {
2135 	if (!ap_qci_info->flags)	/* QCI not supported */
2136 		return false;
2137 
2138 	memcpy(ap_qci_info_old, ap_qci_info, sizeof(*ap_qci_info));
2139 	ap_qci(ap_qci_info);
2140 
2141 	return memcmp(ap_qci_info, ap_qci_info_old,
2142 		      sizeof(struct ap_config_info)) != 0;
2143 }
2144 
2145 /*
2146  * ap_config_has_new_aps - Check current against old qci info if
2147  * new adapters have appeared. Returns true if at least one new
2148  * adapter in the apm mask is showing up. Existing adapters or
2149  * receding adapters are not counted.
2150  */
2151 static bool ap_config_has_new_aps(void)
2152 {
2153 
2154 	unsigned long m[BITS_TO_LONGS(AP_DEVICES)];
2155 
2156 	if (!ap_qci_info->flags)
2157 		return false;
2158 
2159 	bitmap_andnot(m, (unsigned long *)ap_qci_info->apm,
2160 		      (unsigned long *)ap_qci_info_old->apm, AP_DEVICES);
2161 	if (!bitmap_empty(m, AP_DEVICES))
2162 		return true;
2163 
2164 	return false;
2165 }
2166 
2167 /*
2168  * ap_config_has_new_doms - Check current against old qci info if
2169  * new (usage) domains have appeared. Returns true if at least one
2170  * new domain in the aqm mask is showing up. Existing domains or
2171  * receding domains are not counted.
2172  */
2173 static bool ap_config_has_new_doms(void)
2174 {
2175 	unsigned long m[BITS_TO_LONGS(AP_DOMAINS)];
2176 
2177 	if (!ap_qci_info->flags)
2178 		return false;
2179 
2180 	bitmap_andnot(m, (unsigned long *)ap_qci_info->aqm,
2181 		      (unsigned long *)ap_qci_info_old->aqm, AP_DOMAINS);
2182 	if (!bitmap_empty(m, AP_DOMAINS))
2183 		return true;
2184 
2185 	return false;
2186 }
2187 
2188 /**
2189  * ap_scan_bus(): Scan the AP bus for new devices
2190  * Always run under mutex ap_scan_bus_mutex protection
2191  * which needs to get locked/unlocked by the caller!
2192  * Returns true if any config change has been detected
2193  * during the scan, otherwise false.
2194  */
2195 static bool ap_scan_bus(void)
2196 {
2197 	bool config_changed;
2198 	int ap;
2199 
2200 	pr_debug(">%s\n", __func__);
2201 
2202 	/* (re-)fetch configuration via QCI */
2203 	config_changed = ap_get_configuration();
2204 	if (config_changed) {
2205 		if (ap_config_has_new_aps() || ap_config_has_new_doms()) {
2206 			/*
2207 			 * Appearance of new adapters and/or domains need to
2208 			 * build new ap devices which need to get bound to an
2209 			 * device driver. Thus reset the APQN bindings complete
2210 			 * completion.
2211 			 */
2212 			reinit_completion(&ap_apqn_bindings_complete);
2213 		}
2214 		/* post a config change notify */
2215 		notify_config_changed();
2216 	}
2217 	ap_select_domain();
2218 
2219 	/* loop over all possible adapters */
2220 	for (ap = 0; ap <= ap_max_adapter_id; ap++)
2221 		ap_scan_adapter(ap);
2222 
2223 	/* scan complete notify */
2224 	if (config_changed)
2225 		notify_scan_complete();
2226 
2227 	/* check if there is at least one queue available with default domain */
2228 	if (ap_domain_index >= 0) {
2229 		struct device *dev =
2230 			bus_find_device(&ap_bus_type, NULL,
2231 					(void *)(long)ap_domain_index,
2232 					__match_queue_device_with_queue_id);
2233 		if (dev)
2234 			put_device(dev);
2235 		else
2236 			AP_DBF_INFO("%s no queue device with default domain %d available\n",
2237 				    __func__, ap_domain_index);
2238 	}
2239 
2240 	if (atomic64_inc_return(&ap_scan_bus_count) == 1) {
2241 		pr_debug("%s init scan complete\n", __func__);
2242 		ap_send_init_scan_done_uevent();
2243 	}
2244 
2245 	ap_check_bindings_complete();
2246 
2247 	mod_timer(&ap_scan_bus_timer, jiffies + ap_scan_bus_time * HZ);
2248 
2249 	pr_debug("<%s config_changed=%d\n", __func__, config_changed);
2250 
2251 	return config_changed;
2252 }
2253 
2254 /*
2255  * Callback for the ap_scan_bus_timer
2256  * Runs periodically, workqueue timer (ap_scan_bus_time)
2257  */
2258 static void ap_scan_bus_timer_callback(struct timer_list *unused)
2259 {
2260 	/*
2261 	 * schedule work into the system long wq which when
2262 	 * the work is finally executed, calls the AP bus scan.
2263 	 */
2264 	queue_work(system_long_wq, &ap_scan_bus_work);
2265 }
2266 
2267 /*
2268  * Callback for the ap_scan_bus_work
2269  */
2270 static void ap_scan_bus_wq_callback(struct work_struct *unused)
2271 {
2272 	/*
2273 	 * Try to invoke an ap_scan_bus(). If the mutex acquisition
2274 	 * fails there is currently another task already running the
2275 	 * AP scan bus and there is no need to wait and re-trigger the
2276 	 * scan again. Please note at the end of the scan bus function
2277 	 * the AP scan bus timer is re-armed which triggers then the
2278 	 * ap_scan_bus_timer_callback which enqueues a work into the
2279 	 * system_long_wq which invokes this function here again.
2280 	 */
2281 	if (mutex_trylock(&ap_scan_bus_mutex)) {
2282 		ap_scan_bus_result = ap_scan_bus();
2283 		mutex_unlock(&ap_scan_bus_mutex);
2284 	}
2285 }
2286 
2287 static inline void __exit ap_async_exit(void)
2288 {
2289 	if (ap_thread_flag)
2290 		ap_poll_thread_stop();
2291 	chsc_notifier_unregister(&ap_bus_nb);
2292 	cancel_work(&ap_scan_bus_work);
2293 	hrtimer_cancel(&ap_poll_timer);
2294 	timer_delete(&ap_scan_bus_timer);
2295 }
2296 
2297 static inline int __init ap_async_init(void)
2298 {
2299 	int rc;
2300 
2301 	/* Setup the AP bus rescan timer. */
2302 	timer_setup(&ap_scan_bus_timer, ap_scan_bus_timer_callback, 0);
2303 
2304 	/*
2305 	 * Setup the high resolution poll timer.
2306 	 * If we are running under z/VM adjust polling to z/VM polling rate.
2307 	 */
2308 	if (MACHINE_IS_VM)
2309 		poll_high_timeout = 1500000;
2310 	hrtimer_init(&ap_poll_timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
2311 	ap_poll_timer.function = ap_poll_timeout;
2312 
2313 	queue_work(system_long_wq, &ap_scan_bus_work);
2314 
2315 	rc = chsc_notifier_register(&ap_bus_nb);
2316 	if (rc)
2317 		goto out;
2318 
2319 	/* Start the low priority AP bus poll thread. */
2320 	if (!ap_thread_flag)
2321 		return 0;
2322 
2323 	rc = ap_poll_thread_start();
2324 	if (rc)
2325 		goto out_notifier;
2326 
2327 	return 0;
2328 
2329 out_notifier:
2330 	chsc_notifier_unregister(&ap_bus_nb);
2331 out:
2332 	cancel_work(&ap_scan_bus_work);
2333 	hrtimer_cancel(&ap_poll_timer);
2334 	timer_delete(&ap_scan_bus_timer);
2335 	return rc;
2336 }
2337 
2338 static inline void ap_irq_exit(void)
2339 {
2340 	if (ap_irq_flag)
2341 		unregister_adapter_interrupt(&ap_airq);
2342 }
2343 
2344 static inline int __init ap_irq_init(void)
2345 {
2346 	int rc;
2347 
2348 	if (!ap_interrupts_available() || !ap_useirq)
2349 		return 0;
2350 
2351 	rc = register_adapter_interrupt(&ap_airq);
2352 	ap_irq_flag = (rc == 0);
2353 
2354 	return rc;
2355 }
2356 
2357 static inline void ap_debug_exit(void)
2358 {
2359 	debug_unregister(ap_dbf_info);
2360 }
2361 
2362 static inline int __init ap_debug_init(void)
2363 {
2364 	ap_dbf_info = debug_register("ap", 2, 1,
2365 				     AP_DBF_MAX_SPRINTF_ARGS * sizeof(long));
2366 	debug_register_view(ap_dbf_info, &debug_sprintf_view);
2367 	debug_set_level(ap_dbf_info, DBF_ERR);
2368 
2369 	return 0;
2370 }
2371 
2372 static void __init ap_perms_init(void)
2373 {
2374 	/* all resources usable if no kernel parameter string given */
2375 	memset(&ap_perms.ioctlm, 0xFF, sizeof(ap_perms.ioctlm));
2376 	memset(&ap_perms.apm, 0xFF, sizeof(ap_perms.apm));
2377 	memset(&ap_perms.aqm, 0xFF, sizeof(ap_perms.aqm));
2378 
2379 	/* apm kernel parameter string */
2380 	if (apm_str) {
2381 		memset(&ap_perms.apm, 0, sizeof(ap_perms.apm));
2382 		ap_parse_mask_str(apm_str, ap_perms.apm, AP_DEVICES,
2383 				  &ap_perms_mutex);
2384 	}
2385 
2386 	/* aqm kernel parameter string */
2387 	if (aqm_str) {
2388 		memset(&ap_perms.aqm, 0, sizeof(ap_perms.aqm));
2389 		ap_parse_mask_str(aqm_str, ap_perms.aqm, AP_DOMAINS,
2390 				  &ap_perms_mutex);
2391 	}
2392 }
2393 
2394 /**
2395  * ap_module_init(): The module initialization code.
2396  *
2397  * Initializes the module.
2398  */
2399 static int __init ap_module_init(void)
2400 {
2401 	int rc;
2402 
2403 	rc = ap_debug_init();
2404 	if (rc)
2405 		return rc;
2406 
2407 	if (!ap_instructions_available()) {
2408 		pr_warn("The hardware system does not support AP instructions\n");
2409 		return -ENODEV;
2410 	}
2411 
2412 	/* init ap_queue hashtable */
2413 	hash_init(ap_queues);
2414 
2415 	/* set up the AP permissions (ioctls, ap and aq masks) */
2416 	ap_perms_init();
2417 
2418 	/* Get AP configuration data if available */
2419 	ap_init_qci_info();
2420 
2421 	/* check default domain setting */
2422 	if (ap_domain_index < -1 || ap_domain_index > ap_max_domain_id ||
2423 	    (ap_domain_index >= 0 &&
2424 	     !test_bit_inv(ap_domain_index, ap_perms.aqm))) {
2425 		pr_warn("%d is not a valid cryptographic domain\n",
2426 			ap_domain_index);
2427 		ap_domain_index = -1;
2428 	}
2429 
2430 	/* Create /sys/bus/ap. */
2431 	rc = bus_register(&ap_bus_type);
2432 	if (rc)
2433 		goto out;
2434 
2435 	/* Create /sys/devices/ap. */
2436 	ap_root_device = root_device_register("ap");
2437 	rc = PTR_ERR_OR_ZERO(ap_root_device);
2438 	if (rc)
2439 		goto out_bus;
2440 	ap_root_device->bus = &ap_bus_type;
2441 
2442 	/* enable interrupts if available */
2443 	rc = ap_irq_init();
2444 	if (rc)
2445 		goto out_device;
2446 
2447 	/* Setup asynchronous work (timers, workqueue, etc). */
2448 	rc = ap_async_init();
2449 	if (rc)
2450 		goto out_irq;
2451 
2452 	return 0;
2453 
2454 out_irq:
2455 	ap_irq_exit();
2456 out_device:
2457 	root_device_unregister(ap_root_device);
2458 out_bus:
2459 	bus_unregister(&ap_bus_type);
2460 out:
2461 	ap_debug_exit();
2462 	return rc;
2463 }
2464 
2465 static void __exit ap_module_exit(void)
2466 {
2467 	ap_async_exit();
2468 	ap_irq_exit();
2469 	root_device_unregister(ap_root_device);
2470 	bus_unregister(&ap_bus_type);
2471 	ap_debug_exit();
2472 }
2473 
2474 module_init(ap_module_init);
2475 module_exit(ap_module_exit);
2476