xref: /linux/drivers/s390/crypto/vfio_ap_ops.c (revision ea8d7647f9ddf1f81e2027ed305299797299aa03)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Adjunct processor matrix VFIO device driver callbacks.
4  *
5  * Copyright IBM Corp. 2018
6  *
7  * Author(s): Tony Krowiak <akrowiak@linux.ibm.com>
8  *	      Halil Pasic <pasic@linux.ibm.com>
9  *	      Pierre Morel <pmorel@linux.ibm.com>
10  */
11 #include <linux/string.h>
12 #include <linux/vfio.h>
13 #include <linux/device.h>
14 #include <linux/list.h>
15 #include <linux/ctype.h>
16 #include <linux/bitops.h>
17 #include <linux/kvm_host.h>
18 #include <linux/module.h>
19 #include <linux/uuid.h>
20 #include <asm/kvm.h>
21 #include <asm/zcrypt.h>
22 
23 #include "vfio_ap_private.h"
24 #include "vfio_ap_debug.h"
25 
26 #define VFIO_AP_MDEV_TYPE_HWVIRT "passthrough"
27 #define VFIO_AP_MDEV_NAME_HWVIRT "VFIO AP Passthrough Device"
28 
29 #define AP_QUEUE_ASSIGNED "assigned"
30 #define AP_QUEUE_UNASSIGNED "unassigned"
31 #define AP_QUEUE_IN_USE "in use"
32 
33 #define AP_RESET_INTERVAL		20	/* Reset sleep interval (20ms)		*/
34 
35 static int vfio_ap_mdev_reset_queues(struct ap_matrix_mdev *matrix_mdev);
36 static int vfio_ap_mdev_reset_qlist(struct list_head *qlist);
37 static struct vfio_ap_queue *vfio_ap_find_queue(int apqn);
38 static const struct vfio_device_ops vfio_ap_matrix_dev_ops;
39 static void vfio_ap_mdev_reset_queue(struct vfio_ap_queue *q);
40 
41 /**
42  * get_update_locks_for_kvm: Acquire the locks required to dynamically update a
43  *			     KVM guest's APCB in the proper order.
44  *
45  * @kvm: a pointer to a struct kvm object containing the KVM guest's APCB.
46  *
47  * The proper locking order is:
48  * 1. matrix_dev->guests_lock: required to use the KVM pointer to update a KVM
49  *			       guest's APCB.
50  * 2. kvm->lock:	       required to update a guest's APCB
51  * 3. matrix_dev->mdevs_lock:  required to access data stored in a matrix_mdev
52  *
53  * Note: If @kvm is NULL, the KVM lock will not be taken.
54  */
55 static inline void get_update_locks_for_kvm(struct kvm *kvm)
56 {
57 	mutex_lock(&matrix_dev->guests_lock);
58 	if (kvm)
59 		mutex_lock(&kvm->lock);
60 	mutex_lock(&matrix_dev->mdevs_lock);
61 }
62 
63 /**
64  * release_update_locks_for_kvm: Release the locks used to dynamically update a
65  *				 KVM guest's APCB in the proper order.
66  *
67  * @kvm: a pointer to a struct kvm object containing the KVM guest's APCB.
68  *
69  * The proper unlocking order is:
70  * 1. matrix_dev->mdevs_lock
71  * 2. kvm->lock
72  * 3. matrix_dev->guests_lock
73  *
74  * Note: If @kvm is NULL, the KVM lock will not be released.
75  */
76 static inline void release_update_locks_for_kvm(struct kvm *kvm)
77 {
78 	mutex_unlock(&matrix_dev->mdevs_lock);
79 	if (kvm)
80 		mutex_unlock(&kvm->lock);
81 	mutex_unlock(&matrix_dev->guests_lock);
82 }
83 
84 /**
85  * get_update_locks_for_mdev: Acquire the locks required to dynamically update a
86  *			      KVM guest's APCB in the proper order.
87  *
88  * @matrix_mdev: a pointer to a struct ap_matrix_mdev object containing the AP
89  *		 configuration data to use to update a KVM guest's APCB.
90  *
91  * The proper locking order is:
92  * 1. matrix_dev->guests_lock: required to use the KVM pointer to update a KVM
93  *			       guest's APCB.
94  * 2. matrix_mdev->kvm->lock:  required to update a guest's APCB
95  * 3. matrix_dev->mdevs_lock:  required to access data stored in a matrix_mdev
96  *
97  * Note: If @matrix_mdev is NULL or is not attached to a KVM guest, the KVM
98  *	 lock will not be taken.
99  */
100 static inline void get_update_locks_for_mdev(struct ap_matrix_mdev *matrix_mdev)
101 {
102 	mutex_lock(&matrix_dev->guests_lock);
103 	if (matrix_mdev && matrix_mdev->kvm)
104 		mutex_lock(&matrix_mdev->kvm->lock);
105 	mutex_lock(&matrix_dev->mdevs_lock);
106 }
107 
108 /**
109  * release_update_locks_for_mdev: Release the locks used to dynamically update a
110  *				  KVM guest's APCB in the proper order.
111  *
112  * @matrix_mdev: a pointer to a struct ap_matrix_mdev object containing the AP
113  *		 configuration data to use to update a KVM guest's APCB.
114  *
115  * The proper unlocking order is:
116  * 1. matrix_dev->mdevs_lock
117  * 2. matrix_mdev->kvm->lock
118  * 3. matrix_dev->guests_lock
119  *
120  * Note: If @matrix_mdev is NULL or is not attached to a KVM guest, the KVM
121  *	 lock will not be released.
122  */
123 static inline void release_update_locks_for_mdev(struct ap_matrix_mdev *matrix_mdev)
124 {
125 	mutex_unlock(&matrix_dev->mdevs_lock);
126 	if (matrix_mdev && matrix_mdev->kvm)
127 		mutex_unlock(&matrix_mdev->kvm->lock);
128 	mutex_unlock(&matrix_dev->guests_lock);
129 }
130 
131 /**
132  * get_update_locks_by_apqn: Find the mdev to which an APQN is assigned and
133  *			     acquire the locks required to update the APCB of
134  *			     the KVM guest to which the mdev is attached.
135  *
136  * @apqn: the APQN of a queue device.
137  *
138  * The proper locking order is:
139  * 1. matrix_dev->guests_lock: required to use the KVM pointer to update a KVM
140  *			       guest's APCB.
141  * 2. matrix_mdev->kvm->lock:  required to update a guest's APCB
142  * 3. matrix_dev->mdevs_lock:  required to access data stored in a matrix_mdev
143  *
144  * Note: If @apqn is not assigned to a matrix_mdev, the matrix_mdev->kvm->lock
145  *	 will not be taken.
146  *
147  * Return: the ap_matrix_mdev object to which @apqn is assigned or NULL if @apqn
148  *	   is not assigned to an ap_matrix_mdev.
149  */
150 static struct ap_matrix_mdev *get_update_locks_by_apqn(int apqn)
151 {
152 	struct ap_matrix_mdev *matrix_mdev;
153 
154 	mutex_lock(&matrix_dev->guests_lock);
155 
156 	list_for_each_entry(matrix_mdev, &matrix_dev->mdev_list, node) {
157 		if (test_bit_inv(AP_QID_CARD(apqn), matrix_mdev->matrix.apm) &&
158 		    test_bit_inv(AP_QID_QUEUE(apqn), matrix_mdev->matrix.aqm)) {
159 			if (matrix_mdev->kvm)
160 				mutex_lock(&matrix_mdev->kvm->lock);
161 
162 			mutex_lock(&matrix_dev->mdevs_lock);
163 
164 			return matrix_mdev;
165 		}
166 	}
167 
168 	mutex_lock(&matrix_dev->mdevs_lock);
169 
170 	return NULL;
171 }
172 
173 /**
174  * get_update_locks_for_queue: get the locks required to update the APCB of the
175  *			       KVM guest to which the matrix mdev linked to a
176  *			       vfio_ap_queue object is attached.
177  *
178  * @q: a pointer to a vfio_ap_queue object.
179  *
180  * The proper locking order is:
181  * 1. q->matrix_dev->guests_lock: required to use the KVM pointer to update a
182  *				  KVM guest's APCB.
183  * 2. q->matrix_mdev->kvm->lock:  required to update a guest's APCB
184  * 3. matrix_dev->mdevs_lock:	  required to access data stored in matrix_mdev
185  *
186  * Note: if @queue is not linked to an ap_matrix_mdev object, the KVM lock
187  *	  will not be taken.
188  */
189 static inline void get_update_locks_for_queue(struct vfio_ap_queue *q)
190 {
191 	mutex_lock(&matrix_dev->guests_lock);
192 	if (q->matrix_mdev && q->matrix_mdev->kvm)
193 		mutex_lock(&q->matrix_mdev->kvm->lock);
194 	mutex_lock(&matrix_dev->mdevs_lock);
195 }
196 
197 /**
198  * vfio_ap_mdev_get_queue - retrieve a queue with a specific APQN from a
199  *			    hash table of queues assigned to a matrix mdev
200  * @matrix_mdev: the matrix mdev
201  * @apqn: The APQN of a queue device
202  *
203  * Return: the pointer to the vfio_ap_queue struct representing the queue or
204  *	   NULL if the queue is not assigned to @matrix_mdev
205  */
206 static struct vfio_ap_queue *vfio_ap_mdev_get_queue(
207 					struct ap_matrix_mdev *matrix_mdev,
208 					int apqn)
209 {
210 	struct vfio_ap_queue *q;
211 
212 	hash_for_each_possible(matrix_mdev->qtable.queues, q, mdev_qnode,
213 			       apqn) {
214 		if (q && q->apqn == apqn)
215 			return q;
216 	}
217 
218 	return NULL;
219 }
220 
221 /**
222  * vfio_ap_wait_for_irqclear - clears the IR bit or gives up after 5 tries
223  * @apqn: The AP Queue number
224  *
225  * Checks the IRQ bit for the status of this APQN using ap_tapq.
226  * Returns if the ap_tapq function succeeded and the bit is clear.
227  * Returns if ap_tapq function failed with invalid, deconfigured or
228  * checkstopped AP.
229  * Otherwise retries up to 5 times after waiting 20ms.
230  */
231 static void vfio_ap_wait_for_irqclear(int apqn)
232 {
233 	struct ap_queue_status status;
234 	int retry = 5;
235 
236 	do {
237 		status = ap_tapq(apqn, NULL);
238 		switch (status.response_code) {
239 		case AP_RESPONSE_NORMAL:
240 		case AP_RESPONSE_RESET_IN_PROGRESS:
241 			if (!status.irq_enabled)
242 				return;
243 			fallthrough;
244 		case AP_RESPONSE_BUSY:
245 			msleep(20);
246 			break;
247 		case AP_RESPONSE_Q_NOT_AVAIL:
248 		case AP_RESPONSE_DECONFIGURED:
249 		case AP_RESPONSE_CHECKSTOPPED:
250 		default:
251 			WARN_ONCE(1, "%s: tapq rc %02x: %04x\n", __func__,
252 				  status.response_code, apqn);
253 			return;
254 		}
255 	} while (--retry);
256 
257 	WARN_ONCE(1, "%s: tapq rc %02x: %04x could not clear IR bit\n",
258 		  __func__, status.response_code, apqn);
259 }
260 
261 /**
262  * vfio_ap_free_aqic_resources - free vfio_ap_queue resources
263  * @q: The vfio_ap_queue
264  *
265  * Unregisters the ISC in the GIB when the saved ISC not invalid.
266  * Unpins the guest's page holding the NIB when it exists.
267  * Resets the saved_iova and saved_isc to invalid values.
268  */
269 static void vfio_ap_free_aqic_resources(struct vfio_ap_queue *q)
270 {
271 	if (!q)
272 		return;
273 	if (q->saved_isc != VFIO_AP_ISC_INVALID &&
274 	    !WARN_ON(!(q->matrix_mdev && q->matrix_mdev->kvm))) {
275 		kvm_s390_gisc_unregister(q->matrix_mdev->kvm, q->saved_isc);
276 		q->saved_isc = VFIO_AP_ISC_INVALID;
277 	}
278 	if (q->saved_iova && !WARN_ON(!q->matrix_mdev)) {
279 		vfio_unpin_pages(&q->matrix_mdev->vdev, q->saved_iova, 1);
280 		q->saved_iova = 0;
281 	}
282 }
283 
284 /**
285  * vfio_ap_irq_disable - disables and clears an ap_queue interrupt
286  * @q: The vfio_ap_queue
287  *
288  * Uses ap_aqic to disable the interruption and in case of success, reset
289  * in progress or IRQ disable command already proceeded: calls
290  * vfio_ap_wait_for_irqclear() to check for the IRQ bit to be clear
291  * and calls vfio_ap_free_aqic_resources() to free the resources associated
292  * with the AP interrupt handling.
293  *
294  * In the case the AP is busy, or a reset is in progress,
295  * retries after 20ms, up to 5 times.
296  *
297  * Returns if ap_aqic function failed with invalid, deconfigured or
298  * checkstopped AP.
299  *
300  * Return: &struct ap_queue_status
301  */
302 static struct ap_queue_status vfio_ap_irq_disable(struct vfio_ap_queue *q)
303 {
304 	union ap_qirq_ctrl aqic_gisa = { .value = 0 };
305 	struct ap_queue_status status;
306 	int retries = 5;
307 
308 	do {
309 		status = ap_aqic(q->apqn, aqic_gisa, 0);
310 		switch (status.response_code) {
311 		case AP_RESPONSE_OTHERWISE_CHANGED:
312 		case AP_RESPONSE_NORMAL:
313 			vfio_ap_wait_for_irqclear(q->apqn);
314 			goto end_free;
315 		case AP_RESPONSE_RESET_IN_PROGRESS:
316 		case AP_RESPONSE_BUSY:
317 			msleep(20);
318 			break;
319 		case AP_RESPONSE_Q_NOT_AVAIL:
320 		case AP_RESPONSE_DECONFIGURED:
321 		case AP_RESPONSE_CHECKSTOPPED:
322 		case AP_RESPONSE_INVALID_ADDRESS:
323 		default:
324 			/* All cases in default means AP not operational */
325 			WARN_ONCE(1, "%s: ap_aqic status %d\n", __func__,
326 				  status.response_code);
327 			goto end_free;
328 		}
329 	} while (retries--);
330 
331 	WARN_ONCE(1, "%s: ap_aqic status %d\n", __func__,
332 		  status.response_code);
333 end_free:
334 	vfio_ap_free_aqic_resources(q);
335 	return status;
336 }
337 
338 /**
339  * vfio_ap_validate_nib - validate a notification indicator byte (nib) address.
340  *
341  * @vcpu: the object representing the vcpu executing the PQAP(AQIC) instruction.
342  * @nib: the location for storing the nib address.
343  *
344  * When the PQAP(AQIC) instruction is executed, general register 2 contains the
345  * address of the notification indicator byte (nib) used for IRQ notification.
346  * This function parses and validates the nib from gr2.
347  *
348  * Return: returns zero if the nib address is a valid; otherwise, returns
349  *	   -EINVAL.
350  */
351 static int vfio_ap_validate_nib(struct kvm_vcpu *vcpu, dma_addr_t *nib)
352 {
353 	*nib = vcpu->run->s.regs.gprs[2];
354 
355 	if (!*nib)
356 		return -EINVAL;
357 	if (kvm_is_error_hva(gfn_to_hva(vcpu->kvm, *nib >> PAGE_SHIFT)))
358 		return -EINVAL;
359 
360 	return 0;
361 }
362 
363 /**
364  * ensure_nib_shared() - Ensure the address of the NIB is secure and shared
365  * @addr: the physical (absolute) address of the NIB
366  *
367  * This function checks whether the NIB page, which has been pinned with
368  * vfio_pin_pages(), is a shared page belonging to a secure guest.
369  *
370  * It will call uv_pin_shared() on it; if the page was already pinned shared
371  * (i.e. if the NIB belongs to a secure guest and is shared), then 0
372  * (success) is returned. If the NIB was not shared, vfio_pin_pages() had
373  * exported it and now it does not belong to the secure guest anymore. In
374  * that case, an error is returned.
375  *
376  * Context: the NIB (at physical address @addr) has to be pinned with
377  *	    vfio_pin_pages() before calling this function.
378  *
379  * Return: 0 in case of success, otherwise an error < 0.
380  */
381 static int ensure_nib_shared(unsigned long addr)
382 {
383 	/*
384 	 * The nib has to be located in shared storage since guest and
385 	 * host access it. vfio_pin_pages() will do a pin shared and
386 	 * if that fails (possibly because it's not a shared page) it
387 	 * calls export. We try to do a second pin shared here so that
388 	 * the UV gives us an error code if we try to pin a non-shared
389 	 * page.
390 	 *
391 	 * If the page is already pinned shared the UV will return a success.
392 	 */
393 	return uv_pin_shared(addr);
394 }
395 
396 /**
397  * vfio_ap_irq_enable - Enable Interruption for a APQN
398  *
399  * @q:	 the vfio_ap_queue holding AQIC parameters
400  * @isc: the guest ISC to register with the GIB interface
401  * @vcpu: the vcpu object containing the registers specifying the parameters
402  *	  passed to the PQAP(AQIC) instruction.
403  *
404  * Pin the NIB saved in *q
405  * Register the guest ISC to GIB interface and retrieve the
406  * host ISC to issue the host side PQAP/AQIC
407  *
408  * status.response_code may be set to AP_RESPONSE_INVALID_ADDRESS in case the
409  * vfio_pin_pages or kvm_s390_gisc_register failed.
410  *
411  * Otherwise return the ap_queue_status returned by the ap_aqic(),
412  * all retry handling will be done by the guest.
413  *
414  * Return: &struct ap_queue_status
415  */
416 static struct ap_queue_status vfio_ap_irq_enable(struct vfio_ap_queue *q,
417 						 int isc,
418 						 struct kvm_vcpu *vcpu)
419 {
420 	union ap_qirq_ctrl aqic_gisa = { .value = 0 };
421 	struct ap_queue_status status = {};
422 	struct kvm_s390_gisa *gisa;
423 	struct page *h_page;
424 	int nisc;
425 	struct kvm *kvm;
426 	phys_addr_t h_nib;
427 	dma_addr_t nib;
428 	int ret;
429 
430 	/* Verify that the notification indicator byte address is valid */
431 	if (vfio_ap_validate_nib(vcpu, &nib)) {
432 		VFIO_AP_DBF_WARN("%s: invalid NIB address: nib=%pad, apqn=%#04x\n",
433 				 __func__, &nib, q->apqn);
434 
435 		status.response_code = AP_RESPONSE_INVALID_ADDRESS;
436 		return status;
437 	}
438 
439 	/* The pin will probably be successful even if the NIB was not shared */
440 	ret = vfio_pin_pages(&q->matrix_mdev->vdev, nib, 1,
441 			     IOMMU_READ | IOMMU_WRITE, &h_page);
442 	switch (ret) {
443 	case 1:
444 		break;
445 	default:
446 		VFIO_AP_DBF_WARN("%s: vfio_pin_pages failed: rc=%d,"
447 				 "nib=%pad, apqn=%#04x\n",
448 				 __func__, ret, &nib, q->apqn);
449 
450 		status.response_code = AP_RESPONSE_INVALID_ADDRESS;
451 		return status;
452 	}
453 
454 	kvm = q->matrix_mdev->kvm;
455 	gisa = kvm->arch.gisa_int.origin;
456 
457 	h_nib = page_to_phys(h_page) | (nib & ~PAGE_MASK);
458 	aqic_gisa.gisc = isc;
459 
460 	/* NIB in non-shared storage is a rc 6 for PV guests */
461 	if (kvm_s390_pv_cpu_is_protected(vcpu) &&
462 	    ensure_nib_shared(h_nib & PAGE_MASK)) {
463 		vfio_unpin_pages(&q->matrix_mdev->vdev, nib, 1);
464 		status.response_code = AP_RESPONSE_INVALID_ADDRESS;
465 		return status;
466 	}
467 
468 	nisc = kvm_s390_gisc_register(kvm, isc);
469 	if (nisc < 0) {
470 		VFIO_AP_DBF_WARN("%s: gisc registration failed: nisc=%d, isc=%d, apqn=%#04x\n",
471 				 __func__, nisc, isc, q->apqn);
472 
473 		vfio_unpin_pages(&q->matrix_mdev->vdev, nib, 1);
474 		status.response_code = AP_RESPONSE_INVALID_ADDRESS;
475 		return status;
476 	}
477 
478 	aqic_gisa.isc = nisc;
479 	aqic_gisa.ir = 1;
480 	aqic_gisa.gisa = virt_to_phys(gisa) >> 4;
481 
482 	status = ap_aqic(q->apqn, aqic_gisa, h_nib);
483 	switch (status.response_code) {
484 	case AP_RESPONSE_NORMAL:
485 		/* See if we did clear older IRQ configuration */
486 		vfio_ap_free_aqic_resources(q);
487 		q->saved_iova = nib;
488 		q->saved_isc = isc;
489 		break;
490 	case AP_RESPONSE_OTHERWISE_CHANGED:
491 		/* We could not modify IRQ settings: clear new configuration */
492 		ret = kvm_s390_gisc_unregister(kvm, isc);
493 		if (ret)
494 			VFIO_AP_DBF_WARN("%s: kvm_s390_gisc_unregister: rc=%d isc=%d, apqn=%#04x\n",
495 					 __func__, ret, isc, q->apqn);
496 		vfio_unpin_pages(&q->matrix_mdev->vdev, nib, 1);
497 		break;
498 	default:
499 		pr_warn("%s: apqn %04x: response: %02x\n", __func__, q->apqn,
500 			status.response_code);
501 		vfio_ap_irq_disable(q);
502 		break;
503 	}
504 
505 	if (status.response_code != AP_RESPONSE_NORMAL) {
506 		VFIO_AP_DBF_WARN("%s: PQAP(AQIC) failed with status=%#02x: "
507 				 "zone=%#x, ir=%#x, gisc=%#x, f=%#x,"
508 				 "gisa=%#x, isc=%#x, apqn=%#04x\n",
509 				 __func__, status.response_code,
510 				 aqic_gisa.zone, aqic_gisa.ir, aqic_gisa.gisc,
511 				 aqic_gisa.gf, aqic_gisa.gisa, aqic_gisa.isc,
512 				 q->apqn);
513 	}
514 
515 	return status;
516 }
517 
518 /**
519  * vfio_ap_le_guid_to_be_uuid - convert a little endian guid array into an array
520  *				of big endian elements that can be passed by
521  *				value to an s390dbf sprintf event function to
522  *				format a UUID string.
523  *
524  * @guid: the object containing the little endian guid
525  * @uuid: a six-element array of long values that can be passed by value as
526  *	  arguments for a formatting string specifying a UUID.
527  *
528  * The S390 Debug Feature (s390dbf) allows the use of "%s" in the sprintf
529  * event functions if the memory for the passed string is available as long as
530  * the debug feature exists. Since a mediated device can be removed at any
531  * time, it's name can not be used because %s passes the reference to the string
532  * in memory and the reference will go stale once the device is removed .
533  *
534  * The s390dbf string formatting function allows a maximum of 9 arguments for a
535  * message to be displayed in the 'sprintf' view. In order to use the bytes
536  * comprising the mediated device's UUID to display the mediated device name,
537  * they will have to be converted into an array whose elements can be passed by
538  * value to sprintf. For example:
539  *
540  * guid array: { 83, 78, 17, 62, bb, f1, f0, 47, 91, 4d, 32, a2, 2e, 3a, 88, 04 }
541  * mdev name: 62177883-f1bb-47f0-914d-32a22e3a8804
542  * array returned: { 62177883, f1bb, 47f0, 914d, 32a2, 2e3a8804 }
543  * formatting string: "%08lx-%04lx-%04lx-%04lx-%02lx%04lx"
544  */
545 static void vfio_ap_le_guid_to_be_uuid(guid_t *guid, unsigned long *uuid)
546 {
547 	/*
548 	 * The input guid is ordered in little endian, so it needs to be
549 	 * reordered for displaying a UUID as a string. This specifies the
550 	 * guid indices in proper order.
551 	 */
552 	uuid[0] = le32_to_cpup((__le32 *)guid);
553 	uuid[1] = le16_to_cpup((__le16 *)&guid->b[4]);
554 	uuid[2] = le16_to_cpup((__le16 *)&guid->b[6]);
555 	uuid[3] = *((__u16 *)&guid->b[8]);
556 	uuid[4] = *((__u16 *)&guid->b[10]);
557 	uuid[5] = *((__u32 *)&guid->b[12]);
558 }
559 
560 /**
561  * handle_pqap - PQAP instruction callback
562  *
563  * @vcpu: The vcpu on which we received the PQAP instruction
564  *
565  * Get the general register contents to initialize internal variables.
566  * REG[0]: APQN
567  * REG[1]: IR and ISC
568  * REG[2]: NIB
569  *
570  * Response.status may be set to following Response Code:
571  * - AP_RESPONSE_Q_NOT_AVAIL: if the queue is not available
572  * - AP_RESPONSE_DECONFIGURED: if the queue is not configured
573  * - AP_RESPONSE_NORMAL (0) : in case of success
574  *   Check vfio_ap_setirq() and vfio_ap_clrirq() for other possible RC.
575  * We take the matrix_dev lock to ensure serialization on queues and
576  * mediated device access.
577  *
578  * Return: 0 if we could handle the request inside KVM.
579  * Otherwise, returns -EOPNOTSUPP to let QEMU handle the fault.
580  */
581 static int handle_pqap(struct kvm_vcpu *vcpu)
582 {
583 	uint64_t status;
584 	uint16_t apqn;
585 	unsigned long uuid[6];
586 	struct vfio_ap_queue *q;
587 	struct ap_queue_status qstatus = {
588 			       .response_code = AP_RESPONSE_Q_NOT_AVAIL, };
589 	struct ap_matrix_mdev *matrix_mdev;
590 
591 	apqn = vcpu->run->s.regs.gprs[0] & 0xffff;
592 
593 	/* If we do not use the AIV facility just go to userland */
594 	if (!(vcpu->arch.sie_block->eca & ECA_AIV)) {
595 		VFIO_AP_DBF_WARN("%s: AIV facility not installed: apqn=0x%04x, eca=0x%04x\n",
596 				 __func__, apqn, vcpu->arch.sie_block->eca);
597 
598 		return -EOPNOTSUPP;
599 	}
600 
601 	mutex_lock(&matrix_dev->mdevs_lock);
602 
603 	if (!vcpu->kvm->arch.crypto.pqap_hook) {
604 		VFIO_AP_DBF_WARN("%s: PQAP(AQIC) hook not registered with the vfio_ap driver: apqn=0x%04x\n",
605 				 __func__, apqn);
606 
607 		goto out_unlock;
608 	}
609 
610 	matrix_mdev = container_of(vcpu->kvm->arch.crypto.pqap_hook,
611 				   struct ap_matrix_mdev, pqap_hook);
612 
613 	/* If the there is no guest using the mdev, there is nothing to do */
614 	if (!matrix_mdev->kvm) {
615 		vfio_ap_le_guid_to_be_uuid(&matrix_mdev->mdev->uuid, uuid);
616 		VFIO_AP_DBF_WARN("%s: mdev %08lx-%04lx-%04lx-%04lx-%04lx%08lx not in use: apqn=0x%04x\n",
617 				 __func__, uuid[0],  uuid[1], uuid[2],
618 				 uuid[3], uuid[4], uuid[5], apqn);
619 		goto out_unlock;
620 	}
621 
622 	q = vfio_ap_mdev_get_queue(matrix_mdev, apqn);
623 	if (!q) {
624 		VFIO_AP_DBF_WARN("%s: Queue %02x.%04x not bound to the vfio_ap driver\n",
625 				 __func__, AP_QID_CARD(apqn),
626 				 AP_QID_QUEUE(apqn));
627 		goto out_unlock;
628 	}
629 
630 	status = vcpu->run->s.regs.gprs[1];
631 
632 	/* If IR bit(16) is set we enable the interrupt */
633 	if ((status >> (63 - 16)) & 0x01)
634 		qstatus = vfio_ap_irq_enable(q, status & 0x07, vcpu);
635 	else
636 		qstatus = vfio_ap_irq_disable(q);
637 
638 out_unlock:
639 	memcpy(&vcpu->run->s.regs.gprs[1], &qstatus, sizeof(qstatus));
640 	vcpu->run->s.regs.gprs[1] >>= 32;
641 	mutex_unlock(&matrix_dev->mdevs_lock);
642 	return 0;
643 }
644 
645 static void vfio_ap_matrix_init(struct ap_config_info *info,
646 				struct ap_matrix *matrix)
647 {
648 	matrix->apm_max = info->apxa ? info->na : 63;
649 	matrix->aqm_max = info->apxa ? info->nd : 15;
650 	matrix->adm_max = info->apxa ? info->nd : 15;
651 }
652 
653 static void signal_guest_ap_cfg_changed(struct ap_matrix_mdev *matrix_mdev)
654 {
655 	if (matrix_mdev->cfg_chg_trigger)
656 		eventfd_signal(matrix_mdev->cfg_chg_trigger);
657 }
658 
659 static void vfio_ap_mdev_update_guest_apcb(struct ap_matrix_mdev *matrix_mdev)
660 {
661 	if (matrix_mdev->kvm) {
662 		kvm_arch_crypto_set_masks(matrix_mdev->kvm,
663 					  matrix_mdev->shadow_apcb.apm,
664 					  matrix_mdev->shadow_apcb.aqm,
665 					  matrix_mdev->shadow_apcb.adm);
666 
667 		signal_guest_ap_cfg_changed(matrix_mdev);
668 	}
669 }
670 
671 static bool vfio_ap_mdev_filter_cdoms(struct ap_matrix_mdev *matrix_mdev)
672 {
673 	DECLARE_BITMAP(prev_shadow_adm, AP_DOMAINS);
674 
675 	bitmap_copy(prev_shadow_adm, matrix_mdev->shadow_apcb.adm, AP_DOMAINS);
676 	bitmap_and(matrix_mdev->shadow_apcb.adm, matrix_mdev->matrix.adm,
677 		   (unsigned long *)matrix_dev->info.adm, AP_DOMAINS);
678 
679 	return !bitmap_equal(prev_shadow_adm, matrix_mdev->shadow_apcb.adm,
680 			     AP_DOMAINS);
681 }
682 
683 static bool _queue_passable(struct vfio_ap_queue *q)
684 {
685 	if (!q)
686 		return false;
687 
688 	switch (q->reset_status.response_code) {
689 	case AP_RESPONSE_NORMAL:
690 	case AP_RESPONSE_DECONFIGURED:
691 	case AP_RESPONSE_CHECKSTOPPED:
692 		return true;
693 	default:
694 		return false;
695 	}
696 }
697 
698 /*
699  * vfio_ap_mdev_filter_matrix - filter the APQNs assigned to the matrix mdev
700  *				to ensure no queue devices are passed through to
701  *				the guest that are not bound to the vfio_ap
702  *				device driver.
703  *
704  * @matrix_mdev: the matrix mdev whose matrix is to be filtered.
705  * @apm_filtered: a 256-bit bitmap for storing the APIDs filtered from the
706  *		  guest's AP configuration that are still in the host's AP
707  *		  configuration.
708  *
709  * Note: If an APQN referencing a queue device that is not bound to the vfio_ap
710  *	 driver, its APID will be filtered from the guest's APCB. The matrix
711  *	 structure precludes filtering an individual APQN, so its APID will be
712  *	 filtered. Consequently, all queues associated with the adapter that
713  *	 are in the host's AP configuration must be reset. If queues are
714  *	 subsequently made available again to the guest, they should re-appear
715  *	 in a reset state
716  *
717  * Return: a boolean value indicating whether the KVM guest's APCB was changed
718  *	   by the filtering or not.
719  */
720 static bool vfio_ap_mdev_filter_matrix(struct ap_matrix_mdev *matrix_mdev,
721 				       unsigned long *apm_filtered)
722 {
723 	unsigned long apid, apqi, apqn;
724 	DECLARE_BITMAP(prev_shadow_apm, AP_DEVICES);
725 	DECLARE_BITMAP(prev_shadow_aqm, AP_DOMAINS);
726 
727 	bitmap_copy(prev_shadow_apm, matrix_mdev->shadow_apcb.apm, AP_DEVICES);
728 	bitmap_copy(prev_shadow_aqm, matrix_mdev->shadow_apcb.aqm, AP_DOMAINS);
729 	vfio_ap_matrix_init(&matrix_dev->info, &matrix_mdev->shadow_apcb);
730 	bitmap_clear(apm_filtered, 0, AP_DEVICES);
731 
732 	/*
733 	 * Copy the adapters, domains and control domains to the shadow_apcb
734 	 * from the matrix mdev, but only those that are assigned to the host's
735 	 * AP configuration.
736 	 */
737 	bitmap_and(matrix_mdev->shadow_apcb.apm, matrix_mdev->matrix.apm,
738 		   (unsigned long *)matrix_dev->info.apm, AP_DEVICES);
739 	bitmap_and(matrix_mdev->shadow_apcb.aqm, matrix_mdev->matrix.aqm,
740 		   (unsigned long *)matrix_dev->info.aqm, AP_DOMAINS);
741 
742 	for_each_set_bit_inv(apid, matrix_mdev->shadow_apcb.apm, AP_DEVICES) {
743 		for_each_set_bit_inv(apqi, matrix_mdev->shadow_apcb.aqm,
744 				     AP_DOMAINS) {
745 			/*
746 			 * If the APQN is not bound to the vfio_ap device
747 			 * driver, then we can't assign it to the guest's
748 			 * AP configuration. The AP architecture won't
749 			 * allow filtering of a single APQN, so let's filter
750 			 * the APID since an adapter represents a physical
751 			 * hardware device.
752 			 */
753 			apqn = AP_MKQID(apid, apqi);
754 			if (!_queue_passable(vfio_ap_mdev_get_queue(matrix_mdev, apqn))) {
755 				clear_bit_inv(apid, matrix_mdev->shadow_apcb.apm);
756 
757 				/*
758 				 * If the adapter was previously plugged into
759 				 * the guest, let's let the caller know that
760 				 * the APID was filtered.
761 				 */
762 				if (test_bit_inv(apid, prev_shadow_apm))
763 					set_bit_inv(apid, apm_filtered);
764 
765 				break;
766 			}
767 		}
768 	}
769 
770 	return !bitmap_equal(prev_shadow_apm, matrix_mdev->shadow_apcb.apm,
771 			     AP_DEVICES) ||
772 	       !bitmap_equal(prev_shadow_aqm, matrix_mdev->shadow_apcb.aqm,
773 			     AP_DOMAINS);
774 }
775 
776 static int vfio_ap_mdev_init_dev(struct vfio_device *vdev)
777 {
778 	struct ap_matrix_mdev *matrix_mdev =
779 		container_of(vdev, struct ap_matrix_mdev, vdev);
780 
781 	matrix_mdev->mdev = to_mdev_device(vdev->dev);
782 	vfio_ap_matrix_init(&matrix_dev->info, &matrix_mdev->matrix);
783 	matrix_mdev->pqap_hook = handle_pqap;
784 	vfio_ap_matrix_init(&matrix_dev->info, &matrix_mdev->shadow_apcb);
785 	hash_init(matrix_mdev->qtable.queues);
786 
787 	return 0;
788 }
789 
790 static int vfio_ap_mdev_probe(struct mdev_device *mdev)
791 {
792 	struct ap_matrix_mdev *matrix_mdev;
793 	int ret;
794 
795 	matrix_mdev = vfio_alloc_device(ap_matrix_mdev, vdev, &mdev->dev,
796 					&vfio_ap_matrix_dev_ops);
797 	if (IS_ERR(matrix_mdev))
798 		return PTR_ERR(matrix_mdev);
799 
800 	ret = vfio_register_emulated_iommu_dev(&matrix_mdev->vdev);
801 	if (ret)
802 		goto err_put_vdev;
803 	matrix_mdev->req_trigger = NULL;
804 	matrix_mdev->cfg_chg_trigger = NULL;
805 	dev_set_drvdata(&mdev->dev, matrix_mdev);
806 	mutex_lock(&matrix_dev->mdevs_lock);
807 	list_add(&matrix_mdev->node, &matrix_dev->mdev_list);
808 	mutex_unlock(&matrix_dev->mdevs_lock);
809 	return 0;
810 
811 err_put_vdev:
812 	vfio_put_device(&matrix_mdev->vdev);
813 	return ret;
814 }
815 
816 static void vfio_ap_mdev_link_queue(struct ap_matrix_mdev *matrix_mdev,
817 				    struct vfio_ap_queue *q)
818 {
819 	if (!q || vfio_ap_mdev_get_queue(matrix_mdev, q->apqn))
820 		return;
821 
822 	q->matrix_mdev = matrix_mdev;
823 	hash_add(matrix_mdev->qtable.queues, &q->mdev_qnode, q->apqn);
824 }
825 
826 static void vfio_ap_mdev_link_apqn(struct ap_matrix_mdev *matrix_mdev, int apqn)
827 {
828 	struct vfio_ap_queue *q;
829 
830 	q = vfio_ap_find_queue(apqn);
831 	vfio_ap_mdev_link_queue(matrix_mdev, q);
832 }
833 
834 static void vfio_ap_unlink_queue_fr_mdev(struct vfio_ap_queue *q)
835 {
836 	hash_del(&q->mdev_qnode);
837 }
838 
839 static void vfio_ap_unlink_mdev_fr_queue(struct vfio_ap_queue *q)
840 {
841 	q->matrix_mdev = NULL;
842 }
843 
844 static void vfio_ap_mdev_unlink_fr_queues(struct ap_matrix_mdev *matrix_mdev)
845 {
846 	struct vfio_ap_queue *q;
847 	unsigned long apid, apqi;
848 
849 	for_each_set_bit_inv(apid, matrix_mdev->matrix.apm, AP_DEVICES) {
850 		for_each_set_bit_inv(apqi, matrix_mdev->matrix.aqm,
851 				     AP_DOMAINS) {
852 			q = vfio_ap_mdev_get_queue(matrix_mdev,
853 						   AP_MKQID(apid, apqi));
854 			if (q)
855 				q->matrix_mdev = NULL;
856 		}
857 	}
858 }
859 
860 static void vfio_ap_mdev_remove(struct mdev_device *mdev)
861 {
862 	struct ap_matrix_mdev *matrix_mdev = dev_get_drvdata(&mdev->dev);
863 
864 	vfio_unregister_group_dev(&matrix_mdev->vdev);
865 
866 	mutex_lock(&matrix_dev->guests_lock);
867 	mutex_lock(&matrix_dev->mdevs_lock);
868 	vfio_ap_mdev_reset_queues(matrix_mdev);
869 	vfio_ap_mdev_unlink_fr_queues(matrix_mdev);
870 	list_del(&matrix_mdev->node);
871 	mutex_unlock(&matrix_dev->mdevs_lock);
872 	mutex_unlock(&matrix_dev->guests_lock);
873 	vfio_put_device(&matrix_mdev->vdev);
874 }
875 
876 #define MDEV_SHARING_ERR "Userspace may not re-assign queue %02lx.%04lx " \
877 			 "already assigned to %s"
878 
879 static void vfio_ap_mdev_log_sharing_err(struct ap_matrix_mdev *matrix_mdev,
880 					 unsigned long *apm,
881 					 unsigned long *aqm)
882 {
883 	unsigned long apid, apqi;
884 	const struct device *dev = mdev_dev(matrix_mdev->mdev);
885 	const char *mdev_name = dev_name(dev);
886 
887 	for_each_set_bit_inv(apid, apm, AP_DEVICES)
888 		for_each_set_bit_inv(apqi, aqm, AP_DOMAINS)
889 			dev_warn(dev, MDEV_SHARING_ERR, apid, apqi, mdev_name);
890 }
891 
892 /**
893  * vfio_ap_mdev_verify_no_sharing - verify APQNs are not shared by matrix mdevs
894  *
895  * @mdev_apm: mask indicating the APIDs of the APQNs to be verified
896  * @mdev_aqm: mask indicating the APQIs of the APQNs to be verified
897  *
898  * Verifies that each APQN derived from the Cartesian product of a bitmap of
899  * AP adapter IDs and AP queue indexes is not configured for any matrix
900  * mediated device. AP queue sharing is not allowed.
901  *
902  * Return: 0 if the APQNs are not shared; otherwise return -EADDRINUSE.
903  */
904 static int vfio_ap_mdev_verify_no_sharing(unsigned long *mdev_apm,
905 					  unsigned long *mdev_aqm)
906 {
907 	struct ap_matrix_mdev *matrix_mdev;
908 	DECLARE_BITMAP(apm, AP_DEVICES);
909 	DECLARE_BITMAP(aqm, AP_DOMAINS);
910 
911 	list_for_each_entry(matrix_mdev, &matrix_dev->mdev_list, node) {
912 		/*
913 		 * If the input apm and aqm are fields of the matrix_mdev
914 		 * object, then move on to the next matrix_mdev.
915 		 */
916 		if (mdev_apm == matrix_mdev->matrix.apm &&
917 		    mdev_aqm == matrix_mdev->matrix.aqm)
918 			continue;
919 
920 		memset(apm, 0, sizeof(apm));
921 		memset(aqm, 0, sizeof(aqm));
922 
923 		/*
924 		 * We work on full longs, as we can only exclude the leftover
925 		 * bits in non-inverse order. The leftover is all zeros.
926 		 */
927 		if (!bitmap_and(apm, mdev_apm, matrix_mdev->matrix.apm,
928 				AP_DEVICES))
929 			continue;
930 
931 		if (!bitmap_and(aqm, mdev_aqm, matrix_mdev->matrix.aqm,
932 				AP_DOMAINS))
933 			continue;
934 
935 		vfio_ap_mdev_log_sharing_err(matrix_mdev, apm, aqm);
936 
937 		return -EADDRINUSE;
938 	}
939 
940 	return 0;
941 }
942 
943 /**
944  * vfio_ap_mdev_validate_masks - verify that the APQNs assigned to the mdev are
945  *				 not reserved for the default zcrypt driver and
946  *				 are not assigned to another mdev.
947  *
948  * @matrix_mdev: the mdev to which the APQNs being validated are assigned.
949  *
950  * Return: One of the following values:
951  * o the error returned from the ap_apqn_in_matrix_owned_by_def_drv() function,
952  *   most likely -EBUSY indicating the ap_perms_mutex lock is already held.
953  * o EADDRNOTAVAIL if an APQN assigned to @matrix_mdev is reserved for the
954  *		   zcrypt default driver.
955  * o EADDRINUSE if an APQN assigned to @matrix_mdev is assigned to another mdev
956  * o A zero indicating validation succeeded.
957  */
958 static int vfio_ap_mdev_validate_masks(struct ap_matrix_mdev *matrix_mdev)
959 {
960 	if (ap_apqn_in_matrix_owned_by_def_drv(matrix_mdev->matrix.apm,
961 					       matrix_mdev->matrix.aqm))
962 		return -EADDRNOTAVAIL;
963 
964 	return vfio_ap_mdev_verify_no_sharing(matrix_mdev->matrix.apm,
965 					      matrix_mdev->matrix.aqm);
966 }
967 
968 static void vfio_ap_mdev_link_adapter(struct ap_matrix_mdev *matrix_mdev,
969 				      unsigned long apid)
970 {
971 	unsigned long apqi;
972 
973 	for_each_set_bit_inv(apqi, matrix_mdev->matrix.aqm, AP_DOMAINS)
974 		vfio_ap_mdev_link_apqn(matrix_mdev,
975 				       AP_MKQID(apid, apqi));
976 }
977 
978 static void collect_queues_to_reset(struct ap_matrix_mdev *matrix_mdev,
979 				    unsigned long apid,
980 				    struct list_head *qlist)
981 {
982 	struct vfio_ap_queue *q;
983 	unsigned long  apqi;
984 
985 	for_each_set_bit_inv(apqi, matrix_mdev->shadow_apcb.aqm, AP_DOMAINS) {
986 		q = vfio_ap_mdev_get_queue(matrix_mdev, AP_MKQID(apid, apqi));
987 		if (q)
988 			list_add_tail(&q->reset_qnode, qlist);
989 	}
990 }
991 
992 static void reset_queues_for_apid(struct ap_matrix_mdev *matrix_mdev,
993 				  unsigned long apid)
994 {
995 	struct list_head qlist;
996 
997 	INIT_LIST_HEAD(&qlist);
998 	collect_queues_to_reset(matrix_mdev, apid, &qlist);
999 	vfio_ap_mdev_reset_qlist(&qlist);
1000 }
1001 
1002 static int reset_queues_for_apids(struct ap_matrix_mdev *matrix_mdev,
1003 				  unsigned long *apm_reset)
1004 {
1005 	struct list_head qlist;
1006 	unsigned long apid;
1007 
1008 	if (bitmap_empty(apm_reset, AP_DEVICES))
1009 		return 0;
1010 
1011 	INIT_LIST_HEAD(&qlist);
1012 
1013 	for_each_set_bit_inv(apid, apm_reset, AP_DEVICES)
1014 		collect_queues_to_reset(matrix_mdev, apid, &qlist);
1015 
1016 	return vfio_ap_mdev_reset_qlist(&qlist);
1017 }
1018 
1019 /**
1020  * assign_adapter_store - parses the APID from @buf and sets the
1021  * corresponding bit in the mediated matrix device's APM
1022  *
1023  * @dev:	the matrix device
1024  * @attr:	the mediated matrix device's assign_adapter attribute
1025  * @buf:	a buffer containing the AP adapter number (APID) to
1026  *		be assigned
1027  * @count:	the number of bytes in @buf
1028  *
1029  * Return: the number of bytes processed if the APID is valid; otherwise,
1030  * returns one of the following errors:
1031  *
1032  *	1. -EINVAL
1033  *	   The APID is not a valid number
1034  *
1035  *	2. -ENODEV
1036  *	   The APID exceeds the maximum value configured for the system
1037  *
1038  *	3. -EADDRNOTAVAIL
1039  *	   An APQN derived from the cross product of the APID being assigned
1040  *	   and the APQIs previously assigned is not bound to the vfio_ap device
1041  *	   driver; or, if no APQIs have yet been assigned, the APID is not
1042  *	   contained in an APQN bound to the vfio_ap device driver.
1043  *
1044  *	4. -EADDRINUSE
1045  *	   An APQN derived from the cross product of the APID being assigned
1046  *	   and the APQIs previously assigned is being used by another mediated
1047  *	   matrix device
1048  *
1049  *	5. -EAGAIN
1050  *	   A lock required to validate the mdev's AP configuration could not
1051  *	   be obtained.
1052  */
1053 static ssize_t assign_adapter_store(struct device *dev,
1054 				    struct device_attribute *attr,
1055 				    const char *buf, size_t count)
1056 {
1057 	int ret;
1058 	unsigned long apid;
1059 	DECLARE_BITMAP(apm_filtered, AP_DEVICES);
1060 	struct ap_matrix_mdev *matrix_mdev = dev_get_drvdata(dev);
1061 
1062 	mutex_lock(&ap_perms_mutex);
1063 	get_update_locks_for_mdev(matrix_mdev);
1064 
1065 	ret = kstrtoul(buf, 0, &apid);
1066 	if (ret)
1067 		goto done;
1068 
1069 	if (apid > matrix_mdev->matrix.apm_max) {
1070 		ret = -ENODEV;
1071 		goto done;
1072 	}
1073 
1074 	if (test_bit_inv(apid, matrix_mdev->matrix.apm)) {
1075 		ret = count;
1076 		goto done;
1077 	}
1078 
1079 	set_bit_inv(apid, matrix_mdev->matrix.apm);
1080 
1081 	ret = vfio_ap_mdev_validate_masks(matrix_mdev);
1082 	if (ret) {
1083 		clear_bit_inv(apid, matrix_mdev->matrix.apm);
1084 		goto done;
1085 	}
1086 
1087 	vfio_ap_mdev_link_adapter(matrix_mdev, apid);
1088 
1089 	if (vfio_ap_mdev_filter_matrix(matrix_mdev, apm_filtered)) {
1090 		vfio_ap_mdev_update_guest_apcb(matrix_mdev);
1091 		reset_queues_for_apids(matrix_mdev, apm_filtered);
1092 	}
1093 
1094 	ret = count;
1095 done:
1096 	release_update_locks_for_mdev(matrix_mdev);
1097 	mutex_unlock(&ap_perms_mutex);
1098 
1099 	return ret;
1100 }
1101 static DEVICE_ATTR_WO(assign_adapter);
1102 
1103 static struct vfio_ap_queue
1104 *vfio_ap_unlink_apqn_fr_mdev(struct ap_matrix_mdev *matrix_mdev,
1105 			     unsigned long apid, unsigned long apqi)
1106 {
1107 	struct vfio_ap_queue *q = NULL;
1108 
1109 	q = vfio_ap_mdev_get_queue(matrix_mdev, AP_MKQID(apid, apqi));
1110 	/* If the queue is assigned to the matrix mdev, unlink it. */
1111 	if (q)
1112 		vfio_ap_unlink_queue_fr_mdev(q);
1113 
1114 	return q;
1115 }
1116 
1117 /**
1118  * vfio_ap_mdev_unlink_adapter - unlink all queues associated with unassigned
1119  *				 adapter from the matrix mdev to which the
1120  *				 adapter was assigned.
1121  * @matrix_mdev: the matrix mediated device to which the adapter was assigned.
1122  * @apid: the APID of the unassigned adapter.
1123  * @qlist: list for storing queues associated with unassigned adapter that
1124  *	   need to be reset.
1125  */
1126 static void vfio_ap_mdev_unlink_adapter(struct ap_matrix_mdev *matrix_mdev,
1127 					unsigned long apid,
1128 					struct list_head *qlist)
1129 {
1130 	unsigned long apqi;
1131 	struct vfio_ap_queue *q;
1132 
1133 	for_each_set_bit_inv(apqi, matrix_mdev->matrix.aqm, AP_DOMAINS) {
1134 		q = vfio_ap_unlink_apqn_fr_mdev(matrix_mdev, apid, apqi);
1135 
1136 		if (q && qlist) {
1137 			if (test_bit_inv(apid, matrix_mdev->shadow_apcb.apm) &&
1138 			    test_bit_inv(apqi, matrix_mdev->shadow_apcb.aqm))
1139 				list_add_tail(&q->reset_qnode, qlist);
1140 		}
1141 	}
1142 }
1143 
1144 static void vfio_ap_mdev_hot_unplug_adapters(struct ap_matrix_mdev *matrix_mdev,
1145 					     unsigned long *apids)
1146 {
1147 	struct vfio_ap_queue *q, *tmpq;
1148 	struct list_head qlist;
1149 	unsigned long apid;
1150 	bool apcb_update = false;
1151 
1152 	INIT_LIST_HEAD(&qlist);
1153 
1154 	for_each_set_bit_inv(apid, apids, AP_DEVICES) {
1155 		vfio_ap_mdev_unlink_adapter(matrix_mdev, apid, &qlist);
1156 
1157 		if (test_bit_inv(apid, matrix_mdev->shadow_apcb.apm)) {
1158 			clear_bit_inv(apid, matrix_mdev->shadow_apcb.apm);
1159 			apcb_update = true;
1160 		}
1161 	}
1162 
1163 	/* Only update apcb if needed to avoid impacting guest */
1164 	if (apcb_update)
1165 		vfio_ap_mdev_update_guest_apcb(matrix_mdev);
1166 
1167 	vfio_ap_mdev_reset_qlist(&qlist);
1168 
1169 	list_for_each_entry_safe(q, tmpq, &qlist, reset_qnode) {
1170 		vfio_ap_unlink_mdev_fr_queue(q);
1171 		list_del(&q->reset_qnode);
1172 	}
1173 }
1174 
1175 static void vfio_ap_mdev_hot_unplug_adapter(struct ap_matrix_mdev *matrix_mdev,
1176 					    unsigned long apid)
1177 {
1178 	DECLARE_BITMAP(apids, AP_DEVICES);
1179 
1180 	bitmap_zero(apids, AP_DEVICES);
1181 	set_bit_inv(apid, apids);
1182 	vfio_ap_mdev_hot_unplug_adapters(matrix_mdev, apids);
1183 }
1184 
1185 /**
1186  * unassign_adapter_store - parses the APID from @buf and clears the
1187  * corresponding bit in the mediated matrix device's APM
1188  *
1189  * @dev:	the matrix device
1190  * @attr:	the mediated matrix device's unassign_adapter attribute
1191  * @buf:	a buffer containing the adapter number (APID) to be unassigned
1192  * @count:	the number of bytes in @buf
1193  *
1194  * Return: the number of bytes processed if the APID is valid; otherwise,
1195  * returns one of the following errors:
1196  *	-EINVAL if the APID is not a number
1197  *	-ENODEV if the APID it exceeds the maximum value configured for the
1198  *		system
1199  */
1200 static ssize_t unassign_adapter_store(struct device *dev,
1201 				      struct device_attribute *attr,
1202 				      const char *buf, size_t count)
1203 {
1204 	int ret;
1205 	unsigned long apid;
1206 	struct ap_matrix_mdev *matrix_mdev = dev_get_drvdata(dev);
1207 
1208 	get_update_locks_for_mdev(matrix_mdev);
1209 
1210 	ret = kstrtoul(buf, 0, &apid);
1211 	if (ret)
1212 		goto done;
1213 
1214 	if (apid > matrix_mdev->matrix.apm_max) {
1215 		ret = -ENODEV;
1216 		goto done;
1217 	}
1218 
1219 	if (!test_bit_inv(apid, matrix_mdev->matrix.apm)) {
1220 		ret = count;
1221 		goto done;
1222 	}
1223 
1224 	clear_bit_inv((unsigned long)apid, matrix_mdev->matrix.apm);
1225 	vfio_ap_mdev_hot_unplug_adapter(matrix_mdev, apid);
1226 	ret = count;
1227 done:
1228 	release_update_locks_for_mdev(matrix_mdev);
1229 	return ret;
1230 }
1231 static DEVICE_ATTR_WO(unassign_adapter);
1232 
1233 static void vfio_ap_mdev_link_domain(struct ap_matrix_mdev *matrix_mdev,
1234 				     unsigned long apqi)
1235 {
1236 	unsigned long apid;
1237 
1238 	for_each_set_bit_inv(apid, matrix_mdev->matrix.apm, AP_DEVICES)
1239 		vfio_ap_mdev_link_apqn(matrix_mdev,
1240 				       AP_MKQID(apid, apqi));
1241 }
1242 
1243 /**
1244  * assign_domain_store - parses the APQI from @buf and sets the
1245  * corresponding bit in the mediated matrix device's AQM
1246  *
1247  * @dev:	the matrix device
1248  * @attr:	the mediated matrix device's assign_domain attribute
1249  * @buf:	a buffer containing the AP queue index (APQI) of the domain to
1250  *		be assigned
1251  * @count:	the number of bytes in @buf
1252  *
1253  * Return: the number of bytes processed if the APQI is valid; otherwise returns
1254  * one of the following errors:
1255  *
1256  *	1. -EINVAL
1257  *	   The APQI is not a valid number
1258  *
1259  *	2. -ENODEV
1260  *	   The APQI exceeds the maximum value configured for the system
1261  *
1262  *	3. -EADDRNOTAVAIL
1263  *	   An APQN derived from the cross product of the APQI being assigned
1264  *	   and the APIDs previously assigned is not bound to the vfio_ap device
1265  *	   driver; or, if no APIDs have yet been assigned, the APQI is not
1266  *	   contained in an APQN bound to the vfio_ap device driver.
1267  *
1268  *	4. -EADDRINUSE
1269  *	   An APQN derived from the cross product of the APQI being assigned
1270  *	   and the APIDs previously assigned is being used by another mediated
1271  *	   matrix device
1272  *
1273  *	5. -EAGAIN
1274  *	   The lock required to validate the mdev's AP configuration could not
1275  *	   be obtained.
1276  */
1277 static ssize_t assign_domain_store(struct device *dev,
1278 				   struct device_attribute *attr,
1279 				   const char *buf, size_t count)
1280 {
1281 	int ret;
1282 	unsigned long apqi;
1283 	DECLARE_BITMAP(apm_filtered, AP_DEVICES);
1284 	struct ap_matrix_mdev *matrix_mdev = dev_get_drvdata(dev);
1285 
1286 	mutex_lock(&ap_perms_mutex);
1287 	get_update_locks_for_mdev(matrix_mdev);
1288 
1289 	ret = kstrtoul(buf, 0, &apqi);
1290 	if (ret)
1291 		goto done;
1292 
1293 	if (apqi > matrix_mdev->matrix.aqm_max) {
1294 		ret = -ENODEV;
1295 		goto done;
1296 	}
1297 
1298 	if (test_bit_inv(apqi, matrix_mdev->matrix.aqm)) {
1299 		ret = count;
1300 		goto done;
1301 	}
1302 
1303 	set_bit_inv(apqi, matrix_mdev->matrix.aqm);
1304 
1305 	ret = vfio_ap_mdev_validate_masks(matrix_mdev);
1306 	if (ret) {
1307 		clear_bit_inv(apqi, matrix_mdev->matrix.aqm);
1308 		goto done;
1309 	}
1310 
1311 	vfio_ap_mdev_link_domain(matrix_mdev, apqi);
1312 
1313 	if (vfio_ap_mdev_filter_matrix(matrix_mdev, apm_filtered)) {
1314 		vfio_ap_mdev_update_guest_apcb(matrix_mdev);
1315 		reset_queues_for_apids(matrix_mdev, apm_filtered);
1316 	}
1317 
1318 	ret = count;
1319 done:
1320 	release_update_locks_for_mdev(matrix_mdev);
1321 	mutex_unlock(&ap_perms_mutex);
1322 
1323 	return ret;
1324 }
1325 static DEVICE_ATTR_WO(assign_domain);
1326 
1327 static void vfio_ap_mdev_unlink_domain(struct ap_matrix_mdev *matrix_mdev,
1328 				       unsigned long apqi,
1329 				       struct list_head *qlist)
1330 {
1331 	unsigned long apid;
1332 	struct vfio_ap_queue *q;
1333 
1334 	for_each_set_bit_inv(apid, matrix_mdev->matrix.apm, AP_DEVICES) {
1335 		q = vfio_ap_unlink_apqn_fr_mdev(matrix_mdev, apid, apqi);
1336 
1337 		if (q && qlist) {
1338 			if (test_bit_inv(apid, matrix_mdev->shadow_apcb.apm) &&
1339 			    test_bit_inv(apqi, matrix_mdev->shadow_apcb.aqm))
1340 				list_add_tail(&q->reset_qnode, qlist);
1341 		}
1342 	}
1343 }
1344 
1345 static void vfio_ap_mdev_hot_unplug_domains(struct ap_matrix_mdev *matrix_mdev,
1346 					    unsigned long *apqis)
1347 {
1348 	struct vfio_ap_queue *q, *tmpq;
1349 	struct list_head qlist;
1350 	unsigned long apqi;
1351 	bool apcb_update = false;
1352 
1353 	INIT_LIST_HEAD(&qlist);
1354 
1355 	for_each_set_bit_inv(apqi, apqis, AP_DOMAINS) {
1356 		vfio_ap_mdev_unlink_domain(matrix_mdev, apqi, &qlist);
1357 
1358 		if (test_bit_inv(apqi, matrix_mdev->shadow_apcb.aqm)) {
1359 			clear_bit_inv(apqi, matrix_mdev->shadow_apcb.aqm);
1360 			apcb_update = true;
1361 		}
1362 	}
1363 
1364 	/* Only update apcb if needed to avoid impacting guest */
1365 	if (apcb_update)
1366 		vfio_ap_mdev_update_guest_apcb(matrix_mdev);
1367 
1368 	vfio_ap_mdev_reset_qlist(&qlist);
1369 
1370 	list_for_each_entry_safe(q, tmpq, &qlist, reset_qnode) {
1371 		vfio_ap_unlink_mdev_fr_queue(q);
1372 		list_del(&q->reset_qnode);
1373 	}
1374 }
1375 
1376 static void vfio_ap_mdev_hot_unplug_domain(struct ap_matrix_mdev *matrix_mdev,
1377 					   unsigned long apqi)
1378 {
1379 	DECLARE_BITMAP(apqis, AP_DOMAINS);
1380 
1381 	bitmap_zero(apqis, AP_DEVICES);
1382 	set_bit_inv(apqi, apqis);
1383 	vfio_ap_mdev_hot_unplug_domains(matrix_mdev, apqis);
1384 }
1385 
1386 /**
1387  * unassign_domain_store - parses the APQI from @buf and clears the
1388  * corresponding bit in the mediated matrix device's AQM
1389  *
1390  * @dev:	the matrix device
1391  * @attr:	the mediated matrix device's unassign_domain attribute
1392  * @buf:	a buffer containing the AP queue index (APQI) of the domain to
1393  *		be unassigned
1394  * @count:	the number of bytes in @buf
1395  *
1396  * Return: the number of bytes processed if the APQI is valid; otherwise,
1397  * returns one of the following errors:
1398  *	-EINVAL if the APQI is not a number
1399  *	-ENODEV if the APQI exceeds the maximum value configured for the system
1400  */
1401 static ssize_t unassign_domain_store(struct device *dev,
1402 				     struct device_attribute *attr,
1403 				     const char *buf, size_t count)
1404 {
1405 	int ret;
1406 	unsigned long apqi;
1407 	struct ap_matrix_mdev *matrix_mdev = dev_get_drvdata(dev);
1408 
1409 	get_update_locks_for_mdev(matrix_mdev);
1410 
1411 	ret = kstrtoul(buf, 0, &apqi);
1412 	if (ret)
1413 		goto done;
1414 
1415 	if (apqi > matrix_mdev->matrix.aqm_max) {
1416 		ret = -ENODEV;
1417 		goto done;
1418 	}
1419 
1420 	if (!test_bit_inv(apqi, matrix_mdev->matrix.aqm)) {
1421 		ret = count;
1422 		goto done;
1423 	}
1424 
1425 	clear_bit_inv((unsigned long)apqi, matrix_mdev->matrix.aqm);
1426 	vfio_ap_mdev_hot_unplug_domain(matrix_mdev, apqi);
1427 	ret = count;
1428 
1429 done:
1430 	release_update_locks_for_mdev(matrix_mdev);
1431 	return ret;
1432 }
1433 static DEVICE_ATTR_WO(unassign_domain);
1434 
1435 /**
1436  * assign_control_domain_store - parses the domain ID from @buf and sets
1437  * the corresponding bit in the mediated matrix device's ADM
1438  *
1439  * @dev:	the matrix device
1440  * @attr:	the mediated matrix device's assign_control_domain attribute
1441  * @buf:	a buffer containing the domain ID to be assigned
1442  * @count:	the number of bytes in @buf
1443  *
1444  * Return: the number of bytes processed if the domain ID is valid; otherwise,
1445  * returns one of the following errors:
1446  *	-EINVAL if the ID is not a number
1447  *	-ENODEV if the ID exceeds the maximum value configured for the system
1448  */
1449 static ssize_t assign_control_domain_store(struct device *dev,
1450 					   struct device_attribute *attr,
1451 					   const char *buf, size_t count)
1452 {
1453 	int ret;
1454 	unsigned long id;
1455 	struct ap_matrix_mdev *matrix_mdev = dev_get_drvdata(dev);
1456 
1457 	get_update_locks_for_mdev(matrix_mdev);
1458 
1459 	ret = kstrtoul(buf, 0, &id);
1460 	if (ret)
1461 		goto done;
1462 
1463 	if (id > matrix_mdev->matrix.adm_max) {
1464 		ret = -ENODEV;
1465 		goto done;
1466 	}
1467 
1468 	if (test_bit_inv(id, matrix_mdev->matrix.adm)) {
1469 		ret = count;
1470 		goto done;
1471 	}
1472 
1473 	/* Set the bit in the ADM (bitmask) corresponding to the AP control
1474 	 * domain number (id). The bits in the mask, from most significant to
1475 	 * least significant, correspond to IDs 0 up to the one less than the
1476 	 * number of control domains that can be assigned.
1477 	 */
1478 	set_bit_inv(id, matrix_mdev->matrix.adm);
1479 	if (vfio_ap_mdev_filter_cdoms(matrix_mdev))
1480 		vfio_ap_mdev_update_guest_apcb(matrix_mdev);
1481 
1482 	ret = count;
1483 done:
1484 	release_update_locks_for_mdev(matrix_mdev);
1485 	return ret;
1486 }
1487 static DEVICE_ATTR_WO(assign_control_domain);
1488 
1489 /**
1490  * unassign_control_domain_store - parses the domain ID from @buf and
1491  * clears the corresponding bit in the mediated matrix device's ADM
1492  *
1493  * @dev:	the matrix device
1494  * @attr:	the mediated matrix device's unassign_control_domain attribute
1495  * @buf:	a buffer containing the domain ID to be unassigned
1496  * @count:	the number of bytes in @buf
1497  *
1498  * Return: the number of bytes processed if the domain ID is valid; otherwise,
1499  * returns one of the following errors:
1500  *	-EINVAL if the ID is not a number
1501  *	-ENODEV if the ID exceeds the maximum value configured for the system
1502  */
1503 static ssize_t unassign_control_domain_store(struct device *dev,
1504 					     struct device_attribute *attr,
1505 					     const char *buf, size_t count)
1506 {
1507 	int ret;
1508 	unsigned long domid;
1509 	struct ap_matrix_mdev *matrix_mdev = dev_get_drvdata(dev);
1510 
1511 	get_update_locks_for_mdev(matrix_mdev);
1512 
1513 	ret = kstrtoul(buf, 0, &domid);
1514 	if (ret)
1515 		goto done;
1516 
1517 	if (domid > matrix_mdev->matrix.adm_max) {
1518 		ret = -ENODEV;
1519 		goto done;
1520 	}
1521 
1522 	if (!test_bit_inv(domid, matrix_mdev->matrix.adm)) {
1523 		ret = count;
1524 		goto done;
1525 	}
1526 
1527 	clear_bit_inv(domid, matrix_mdev->matrix.adm);
1528 
1529 	if (test_bit_inv(domid, matrix_mdev->shadow_apcb.adm)) {
1530 		clear_bit_inv(domid, matrix_mdev->shadow_apcb.adm);
1531 		vfio_ap_mdev_update_guest_apcb(matrix_mdev);
1532 	}
1533 
1534 	ret = count;
1535 done:
1536 	release_update_locks_for_mdev(matrix_mdev);
1537 	return ret;
1538 }
1539 static DEVICE_ATTR_WO(unassign_control_domain);
1540 
1541 static ssize_t control_domains_show(struct device *dev,
1542 				    struct device_attribute *dev_attr,
1543 				    char *buf)
1544 {
1545 	unsigned long id;
1546 	struct ap_matrix_mdev *matrix_mdev = dev_get_drvdata(dev);
1547 	unsigned long max_domid = matrix_mdev->matrix.adm_max;
1548 	int nchars = 0;
1549 
1550 	mutex_lock(&matrix_dev->mdevs_lock);
1551 	for_each_set_bit_inv(id, matrix_mdev->matrix.adm, max_domid + 1)
1552 		nchars += sysfs_emit_at(buf, nchars, "%04lx\n", id);
1553 	mutex_unlock(&matrix_dev->mdevs_lock);
1554 
1555 	return nchars;
1556 }
1557 static DEVICE_ATTR_RO(control_domains);
1558 
1559 static ssize_t vfio_ap_mdev_matrix_show(struct ap_matrix *matrix, char *buf)
1560 {
1561 	unsigned long apid;
1562 	unsigned long apqi;
1563 	unsigned long apid1;
1564 	unsigned long apqi1;
1565 	unsigned long napm_bits = matrix->apm_max + 1;
1566 	unsigned long naqm_bits = matrix->aqm_max + 1;
1567 	int nchars = 0;
1568 
1569 	apid1 = find_first_bit_inv(matrix->apm, napm_bits);
1570 	apqi1 = find_first_bit_inv(matrix->aqm, naqm_bits);
1571 
1572 	if ((apid1 < napm_bits) && (apqi1 < naqm_bits)) {
1573 		for_each_set_bit_inv(apid, matrix->apm, napm_bits) {
1574 			for_each_set_bit_inv(apqi, matrix->aqm, naqm_bits)
1575 				nchars += sysfs_emit_at(buf, nchars, "%02lx.%04lx\n", apid, apqi);
1576 		}
1577 	} else if (apid1 < napm_bits) {
1578 		for_each_set_bit_inv(apid, matrix->apm, napm_bits)
1579 			nchars += sysfs_emit_at(buf, nchars, "%02lx.\n", apid);
1580 	} else if (apqi1 < naqm_bits) {
1581 		for_each_set_bit_inv(apqi, matrix->aqm, naqm_bits)
1582 			nchars += sysfs_emit_at(buf, nchars, ".%04lx\n", apqi);
1583 	}
1584 
1585 	return nchars;
1586 }
1587 
1588 static ssize_t matrix_show(struct device *dev, struct device_attribute *attr,
1589 			   char *buf)
1590 {
1591 	ssize_t nchars;
1592 	struct ap_matrix_mdev *matrix_mdev = dev_get_drvdata(dev);
1593 
1594 	mutex_lock(&matrix_dev->mdevs_lock);
1595 	nchars = vfio_ap_mdev_matrix_show(&matrix_mdev->matrix, buf);
1596 	mutex_unlock(&matrix_dev->mdevs_lock);
1597 
1598 	return nchars;
1599 }
1600 static DEVICE_ATTR_RO(matrix);
1601 
1602 static ssize_t guest_matrix_show(struct device *dev,
1603 				 struct device_attribute *attr, char *buf)
1604 {
1605 	ssize_t nchars;
1606 	struct ap_matrix_mdev *matrix_mdev = dev_get_drvdata(dev);
1607 
1608 	mutex_lock(&matrix_dev->mdevs_lock);
1609 	nchars = vfio_ap_mdev_matrix_show(&matrix_mdev->shadow_apcb, buf);
1610 	mutex_unlock(&matrix_dev->mdevs_lock);
1611 
1612 	return nchars;
1613 }
1614 static DEVICE_ATTR_RO(guest_matrix);
1615 
1616 static ssize_t write_ap_bitmap(unsigned long *bitmap, char *buf, int offset, char sep)
1617 {
1618 	return sysfs_emit_at(buf, offset, "0x%016lx%016lx%016lx%016lx%c",
1619 			 bitmap[0], bitmap[1], bitmap[2], bitmap[3], sep);
1620 }
1621 
1622 static ssize_t ap_config_show(struct device *dev, struct device_attribute *attr,
1623 			      char *buf)
1624 {
1625 	struct ap_matrix_mdev *matrix_mdev = dev_get_drvdata(dev);
1626 	int idx = 0;
1627 
1628 	idx += write_ap_bitmap(matrix_mdev->matrix.apm, buf, idx, ',');
1629 	idx += write_ap_bitmap(matrix_mdev->matrix.aqm, buf, idx, ',');
1630 	idx += write_ap_bitmap(matrix_mdev->matrix.adm, buf, idx, '\n');
1631 
1632 	return idx;
1633 }
1634 
1635 /* Number of characters needed for a complete hex mask representing the bits in ..  */
1636 #define AP_DEVICES_STRLEN	(AP_DEVICES / 4 + 3)
1637 #define AP_DOMAINS_STRLEN	(AP_DOMAINS / 4 + 3)
1638 #define AP_CONFIG_STRLEN	(AP_DEVICES_STRLEN + 2 * AP_DOMAINS_STRLEN)
1639 
1640 static int parse_bitmap(char **strbufptr, unsigned long *bitmap, int nbits)
1641 {
1642 	char *curmask;
1643 
1644 	curmask = strsep(strbufptr, ",\n");
1645 	if (!curmask)
1646 		return -EINVAL;
1647 
1648 	bitmap_clear(bitmap, 0, nbits);
1649 	return ap_hex2bitmap(curmask, bitmap, nbits);
1650 }
1651 
1652 static int ap_matrix_overflow_check(struct ap_matrix_mdev *matrix_mdev)
1653 {
1654 	unsigned long bit;
1655 
1656 	for_each_set_bit_inv(bit, matrix_mdev->matrix.apm, AP_DEVICES) {
1657 		if (bit > matrix_mdev->matrix.apm_max)
1658 			return -ENODEV;
1659 	}
1660 
1661 	for_each_set_bit_inv(bit, matrix_mdev->matrix.aqm, AP_DOMAINS) {
1662 		if (bit > matrix_mdev->matrix.aqm_max)
1663 			return -ENODEV;
1664 	}
1665 
1666 	for_each_set_bit_inv(bit, matrix_mdev->matrix.adm, AP_DOMAINS) {
1667 		if (bit > matrix_mdev->matrix.adm_max)
1668 			return -ENODEV;
1669 	}
1670 
1671 	return 0;
1672 }
1673 
1674 static void ap_matrix_copy(struct ap_matrix *dst, struct ap_matrix *src)
1675 {
1676 	/* This check works around false positive gcc -Wstringop-overread */
1677 	if (!src)
1678 		return;
1679 
1680 	bitmap_copy(dst->apm, src->apm, AP_DEVICES);
1681 	bitmap_copy(dst->aqm, src->aqm, AP_DOMAINS);
1682 	bitmap_copy(dst->adm, src->adm, AP_DOMAINS);
1683 }
1684 
1685 static ssize_t ap_config_store(struct device *dev, struct device_attribute *attr,
1686 			       const char *buf, size_t count)
1687 {
1688 	struct ap_matrix_mdev *matrix_mdev = dev_get_drvdata(dev);
1689 	struct ap_matrix m_new, m_old, m_added, m_removed;
1690 	DECLARE_BITMAP(apm_filtered, AP_DEVICES);
1691 	unsigned long newbit;
1692 	char *newbuf, *rest;
1693 	int rc = count;
1694 	bool do_update;
1695 
1696 	newbuf = kstrndup(buf, AP_CONFIG_STRLEN, GFP_KERNEL);
1697 	if (!newbuf)
1698 		return -ENOMEM;
1699 	rest = newbuf;
1700 
1701 	mutex_lock(&ap_perms_mutex);
1702 	get_update_locks_for_mdev(matrix_mdev);
1703 
1704 	/* Save old state */
1705 	ap_matrix_copy(&m_old, &matrix_mdev->matrix);
1706 	if (parse_bitmap(&rest, m_new.apm, AP_DEVICES) ||
1707 	    parse_bitmap(&rest, m_new.aqm, AP_DOMAINS) ||
1708 	    parse_bitmap(&rest, m_new.adm, AP_DOMAINS)) {
1709 		rc = -EINVAL;
1710 		goto out;
1711 	}
1712 
1713 	bitmap_andnot(m_removed.apm, m_old.apm, m_new.apm, AP_DEVICES);
1714 	bitmap_andnot(m_removed.aqm, m_old.aqm, m_new.aqm, AP_DOMAINS);
1715 	bitmap_andnot(m_added.apm, m_new.apm, m_old.apm, AP_DEVICES);
1716 	bitmap_andnot(m_added.aqm, m_new.aqm, m_old.aqm, AP_DOMAINS);
1717 
1718 	/* Need new bitmaps in matrix_mdev for validation */
1719 	ap_matrix_copy(&matrix_mdev->matrix, &m_new);
1720 
1721 	/* Ensure new state is valid, else undo new state */
1722 	rc = vfio_ap_mdev_validate_masks(matrix_mdev);
1723 	if (rc) {
1724 		ap_matrix_copy(&matrix_mdev->matrix, &m_old);
1725 		goto out;
1726 	}
1727 	rc = ap_matrix_overflow_check(matrix_mdev);
1728 	if (rc) {
1729 		ap_matrix_copy(&matrix_mdev->matrix, &m_old);
1730 		goto out;
1731 	}
1732 	rc = count;
1733 
1734 	/* Need old bitmaps in matrix_mdev for unplug/unlink */
1735 	ap_matrix_copy(&matrix_mdev->matrix, &m_old);
1736 
1737 	/* Unlink removed adapters/domains */
1738 	vfio_ap_mdev_hot_unplug_adapters(matrix_mdev, m_removed.apm);
1739 	vfio_ap_mdev_hot_unplug_domains(matrix_mdev, m_removed.aqm);
1740 
1741 	/* Need new bitmaps in matrix_mdev for linking new adapters/domains */
1742 	ap_matrix_copy(&matrix_mdev->matrix, &m_new);
1743 
1744 	/* Link newly added adapters */
1745 	for_each_set_bit_inv(newbit, m_added.apm, AP_DEVICES)
1746 		vfio_ap_mdev_link_adapter(matrix_mdev, newbit);
1747 
1748 	for_each_set_bit_inv(newbit, m_added.aqm, AP_DOMAINS)
1749 		vfio_ap_mdev_link_domain(matrix_mdev, newbit);
1750 
1751 	/* filter resources not bound to vfio-ap */
1752 	do_update = vfio_ap_mdev_filter_matrix(matrix_mdev, apm_filtered);
1753 	do_update |= vfio_ap_mdev_filter_cdoms(matrix_mdev);
1754 
1755 	/* Apply changes to shadow apbc if things changed */
1756 	if (do_update) {
1757 		vfio_ap_mdev_update_guest_apcb(matrix_mdev);
1758 		reset_queues_for_apids(matrix_mdev, apm_filtered);
1759 	}
1760 out:
1761 	release_update_locks_for_mdev(matrix_mdev);
1762 	mutex_unlock(&ap_perms_mutex);
1763 	kfree(newbuf);
1764 	return rc;
1765 }
1766 static DEVICE_ATTR_RW(ap_config);
1767 
1768 static struct attribute *vfio_ap_mdev_attrs[] = {
1769 	&dev_attr_assign_adapter.attr,
1770 	&dev_attr_unassign_adapter.attr,
1771 	&dev_attr_assign_domain.attr,
1772 	&dev_attr_unassign_domain.attr,
1773 	&dev_attr_assign_control_domain.attr,
1774 	&dev_attr_unassign_control_domain.attr,
1775 	&dev_attr_ap_config.attr,
1776 	&dev_attr_control_domains.attr,
1777 	&dev_attr_matrix.attr,
1778 	&dev_attr_guest_matrix.attr,
1779 	NULL,
1780 };
1781 
1782 static struct attribute_group vfio_ap_mdev_attr_group = {
1783 	.attrs = vfio_ap_mdev_attrs
1784 };
1785 
1786 static const struct attribute_group *vfio_ap_mdev_attr_groups[] = {
1787 	&vfio_ap_mdev_attr_group,
1788 	NULL
1789 };
1790 
1791 /**
1792  * vfio_ap_mdev_set_kvm - sets all data for @matrix_mdev that are needed
1793  * to manage AP resources for the guest whose state is represented by @kvm
1794  *
1795  * @matrix_mdev: a mediated matrix device
1796  * @kvm: reference to KVM instance
1797  *
1798  * Return: 0 if no other mediated matrix device has a reference to @kvm;
1799  * otherwise, returns an -EPERM.
1800  */
1801 static int vfio_ap_mdev_set_kvm(struct ap_matrix_mdev *matrix_mdev,
1802 				struct kvm *kvm)
1803 {
1804 	struct ap_matrix_mdev *m;
1805 
1806 	if (kvm->arch.crypto.crycbd) {
1807 		down_write(&kvm->arch.crypto.pqap_hook_rwsem);
1808 		kvm->arch.crypto.pqap_hook = &matrix_mdev->pqap_hook;
1809 		up_write(&kvm->arch.crypto.pqap_hook_rwsem);
1810 
1811 		get_update_locks_for_kvm(kvm);
1812 
1813 		list_for_each_entry(m, &matrix_dev->mdev_list, node) {
1814 			if (m != matrix_mdev && m->kvm == kvm) {
1815 				release_update_locks_for_kvm(kvm);
1816 				return -EPERM;
1817 			}
1818 		}
1819 
1820 		kvm_get_kvm(kvm);
1821 		matrix_mdev->kvm = kvm;
1822 		vfio_ap_mdev_update_guest_apcb(matrix_mdev);
1823 
1824 		release_update_locks_for_kvm(kvm);
1825 	}
1826 
1827 	return 0;
1828 }
1829 
1830 static void unmap_iova(struct ap_matrix_mdev *matrix_mdev, u64 iova, u64 length)
1831 {
1832 	struct ap_queue_table *qtable = &matrix_mdev->qtable;
1833 	struct vfio_ap_queue *q;
1834 	int loop_cursor;
1835 
1836 	hash_for_each(qtable->queues, loop_cursor, q, mdev_qnode) {
1837 		if (q->saved_iova >= iova && q->saved_iova < iova + length)
1838 			vfio_ap_irq_disable(q);
1839 	}
1840 }
1841 
1842 static void vfio_ap_mdev_dma_unmap(struct vfio_device *vdev, u64 iova,
1843 				   u64 length)
1844 {
1845 	struct ap_matrix_mdev *matrix_mdev =
1846 		container_of(vdev, struct ap_matrix_mdev, vdev);
1847 
1848 	mutex_lock(&matrix_dev->mdevs_lock);
1849 
1850 	unmap_iova(matrix_mdev, iova, length);
1851 
1852 	mutex_unlock(&matrix_dev->mdevs_lock);
1853 }
1854 
1855 /**
1856  * vfio_ap_mdev_unset_kvm - performs clean-up of resources no longer needed
1857  * by @matrix_mdev.
1858  *
1859  * @matrix_mdev: a matrix mediated device
1860  */
1861 static void vfio_ap_mdev_unset_kvm(struct ap_matrix_mdev *matrix_mdev)
1862 {
1863 	struct kvm *kvm = matrix_mdev->kvm;
1864 
1865 	if (kvm && kvm->arch.crypto.crycbd) {
1866 		down_write(&kvm->arch.crypto.pqap_hook_rwsem);
1867 		kvm->arch.crypto.pqap_hook = NULL;
1868 		up_write(&kvm->arch.crypto.pqap_hook_rwsem);
1869 
1870 		get_update_locks_for_kvm(kvm);
1871 
1872 		kvm_arch_crypto_clear_masks(kvm);
1873 		vfio_ap_mdev_reset_queues(matrix_mdev);
1874 		kvm_put_kvm(kvm);
1875 		matrix_mdev->kvm = NULL;
1876 
1877 		release_update_locks_for_kvm(kvm);
1878 	}
1879 }
1880 
1881 static struct vfio_ap_queue *vfio_ap_find_queue(int apqn)
1882 {
1883 	struct ap_queue *queue;
1884 	struct vfio_ap_queue *q = NULL;
1885 
1886 	queue = ap_get_qdev(apqn);
1887 	if (!queue)
1888 		return NULL;
1889 
1890 	if (queue->ap_dev.device.driver == &matrix_dev->vfio_ap_drv->driver)
1891 		q = dev_get_drvdata(&queue->ap_dev.device);
1892 
1893 	put_device(&queue->ap_dev.device);
1894 
1895 	return q;
1896 }
1897 
1898 static int apq_status_check(int apqn, struct ap_queue_status *status)
1899 {
1900 	switch (status->response_code) {
1901 	case AP_RESPONSE_NORMAL:
1902 	case AP_RESPONSE_DECONFIGURED:
1903 	case AP_RESPONSE_CHECKSTOPPED:
1904 		return 0;
1905 	case AP_RESPONSE_RESET_IN_PROGRESS:
1906 	case AP_RESPONSE_BUSY:
1907 		return -EBUSY;
1908 	case AP_RESPONSE_ASSOC_SECRET_NOT_UNIQUE:
1909 	case AP_RESPONSE_ASSOC_FAILED:
1910 		/*
1911 		 * These asynchronous response codes indicate a PQAP(AAPQ)
1912 		 * instruction to associate a secret with the guest failed. All
1913 		 * subsequent AP instructions will end with the asynchronous
1914 		 * response code until the AP queue is reset; so, let's return
1915 		 * a value indicating a reset needs to be performed again.
1916 		 */
1917 		return -EAGAIN;
1918 	default:
1919 		WARN(true,
1920 		     "failed to verify reset of queue %02x.%04x: TAPQ rc=%u\n",
1921 		     AP_QID_CARD(apqn), AP_QID_QUEUE(apqn),
1922 		     status->response_code);
1923 		return -EIO;
1924 	}
1925 }
1926 
1927 #define WAIT_MSG "Waited %dms for reset of queue %02x.%04x (%u, %u, %u)"
1928 
1929 static void apq_reset_check(struct work_struct *reset_work)
1930 {
1931 	int ret = -EBUSY, elapsed = 0;
1932 	struct ap_queue_status status;
1933 	struct vfio_ap_queue *q;
1934 
1935 	q = container_of(reset_work, struct vfio_ap_queue, reset_work);
1936 	memcpy(&status, &q->reset_status, sizeof(status));
1937 	while (true) {
1938 		msleep(AP_RESET_INTERVAL);
1939 		elapsed += AP_RESET_INTERVAL;
1940 		status = ap_tapq(q->apqn, NULL);
1941 		ret = apq_status_check(q->apqn, &status);
1942 		if (ret == -EIO)
1943 			return;
1944 		if (ret == -EBUSY) {
1945 			pr_notice_ratelimited(WAIT_MSG, elapsed,
1946 					      AP_QID_CARD(q->apqn),
1947 					      AP_QID_QUEUE(q->apqn),
1948 					      status.response_code,
1949 					      status.queue_empty,
1950 					      status.irq_enabled);
1951 		} else {
1952 			if (q->reset_status.response_code == AP_RESPONSE_RESET_IN_PROGRESS ||
1953 			    q->reset_status.response_code == AP_RESPONSE_BUSY ||
1954 			    q->reset_status.response_code == AP_RESPONSE_STATE_CHANGE_IN_PROGRESS ||
1955 			    ret == -EAGAIN) {
1956 				status = ap_zapq(q->apqn, 0);
1957 				memcpy(&q->reset_status, &status, sizeof(status));
1958 				continue;
1959 			}
1960 			if (q->saved_isc != VFIO_AP_ISC_INVALID)
1961 				vfio_ap_free_aqic_resources(q);
1962 			break;
1963 		}
1964 	}
1965 }
1966 
1967 static void vfio_ap_mdev_reset_queue(struct vfio_ap_queue *q)
1968 {
1969 	struct ap_queue_status status;
1970 
1971 	if (!q)
1972 		return;
1973 	status = ap_zapq(q->apqn, 0);
1974 	memcpy(&q->reset_status, &status, sizeof(status));
1975 	switch (status.response_code) {
1976 	case AP_RESPONSE_NORMAL:
1977 	case AP_RESPONSE_RESET_IN_PROGRESS:
1978 	case AP_RESPONSE_BUSY:
1979 	case AP_RESPONSE_STATE_CHANGE_IN_PROGRESS:
1980 		/*
1981 		 * Let's verify whether the ZAPQ completed successfully on a work queue.
1982 		 */
1983 		queue_work(system_long_wq, &q->reset_work);
1984 		break;
1985 	case AP_RESPONSE_DECONFIGURED:
1986 	case AP_RESPONSE_CHECKSTOPPED:
1987 		vfio_ap_free_aqic_resources(q);
1988 		break;
1989 	default:
1990 		WARN(true,
1991 		     "PQAP/ZAPQ for %02x.%04x failed with invalid rc=%u\n",
1992 		     AP_QID_CARD(q->apqn), AP_QID_QUEUE(q->apqn),
1993 		     status.response_code);
1994 	}
1995 }
1996 
1997 static int vfio_ap_mdev_reset_queues(struct ap_matrix_mdev *matrix_mdev)
1998 {
1999 	int ret = 0, loop_cursor;
2000 	struct vfio_ap_queue *q;
2001 
2002 	hash_for_each(matrix_mdev->qtable.queues, loop_cursor, q, mdev_qnode)
2003 		vfio_ap_mdev_reset_queue(q);
2004 
2005 	hash_for_each(matrix_mdev->qtable.queues, loop_cursor, q, mdev_qnode) {
2006 		flush_work(&q->reset_work);
2007 
2008 		if (q->reset_status.response_code)
2009 			ret = -EIO;
2010 	}
2011 
2012 	return ret;
2013 }
2014 
2015 static int vfio_ap_mdev_reset_qlist(struct list_head *qlist)
2016 {
2017 	int ret = 0;
2018 	struct vfio_ap_queue *q;
2019 
2020 	list_for_each_entry(q, qlist, reset_qnode)
2021 		vfio_ap_mdev_reset_queue(q);
2022 
2023 	list_for_each_entry(q, qlist, reset_qnode) {
2024 		flush_work(&q->reset_work);
2025 
2026 		if (q->reset_status.response_code)
2027 			ret = -EIO;
2028 	}
2029 
2030 	return ret;
2031 }
2032 
2033 static int vfio_ap_mdev_open_device(struct vfio_device *vdev)
2034 {
2035 	struct ap_matrix_mdev *matrix_mdev =
2036 		container_of(vdev, struct ap_matrix_mdev, vdev);
2037 
2038 	if (!vdev->kvm)
2039 		return -EINVAL;
2040 
2041 	return vfio_ap_mdev_set_kvm(matrix_mdev, vdev->kvm);
2042 }
2043 
2044 static void vfio_ap_mdev_close_device(struct vfio_device *vdev)
2045 {
2046 	struct ap_matrix_mdev *matrix_mdev =
2047 		container_of(vdev, struct ap_matrix_mdev, vdev);
2048 
2049 	vfio_ap_mdev_unset_kvm(matrix_mdev);
2050 }
2051 
2052 static void vfio_ap_mdev_request(struct vfio_device *vdev, unsigned int count)
2053 {
2054 	struct device *dev = vdev->dev;
2055 	struct ap_matrix_mdev *matrix_mdev;
2056 
2057 	matrix_mdev = container_of(vdev, struct ap_matrix_mdev, vdev);
2058 
2059 	get_update_locks_for_mdev(matrix_mdev);
2060 
2061 	if (matrix_mdev->kvm) {
2062 		kvm_arch_crypto_clear_masks(matrix_mdev->kvm);
2063 		signal_guest_ap_cfg_changed(matrix_mdev);
2064 	}
2065 
2066 	if (matrix_mdev->req_trigger) {
2067 		if (!(count % 10))
2068 			dev_notice_ratelimited(dev,
2069 					       "Relaying device request to user (#%u)\n",
2070 					       count);
2071 
2072 		eventfd_signal(matrix_mdev->req_trigger);
2073 	} else if (count == 0) {
2074 		dev_notice(dev,
2075 			   "No device request registered, blocked until released by user\n");
2076 	}
2077 
2078 	release_update_locks_for_mdev(matrix_mdev);
2079 }
2080 
2081 static int vfio_ap_mdev_get_device_info(unsigned long arg)
2082 {
2083 	unsigned long minsz;
2084 	struct vfio_device_info info;
2085 
2086 	minsz = offsetofend(struct vfio_device_info, num_irqs);
2087 
2088 	if (copy_from_user(&info, (void __user *)arg, minsz))
2089 		return -EFAULT;
2090 
2091 	if (info.argsz < minsz)
2092 		return -EINVAL;
2093 
2094 	info.flags = VFIO_DEVICE_FLAGS_AP | VFIO_DEVICE_FLAGS_RESET;
2095 	info.num_regions = 0;
2096 	info.num_irqs = VFIO_AP_NUM_IRQS;
2097 
2098 	return copy_to_user((void __user *)arg, &info, minsz) ? -EFAULT : 0;
2099 }
2100 
2101 static ssize_t vfio_ap_get_irq_info(unsigned long arg)
2102 {
2103 	unsigned long minsz;
2104 	struct vfio_irq_info info;
2105 
2106 	minsz = offsetofend(struct vfio_irq_info, count);
2107 
2108 	if (copy_from_user(&info, (void __user *)arg, minsz))
2109 		return -EFAULT;
2110 
2111 	if (info.argsz < minsz || info.index >= VFIO_AP_NUM_IRQS)
2112 		return -EINVAL;
2113 
2114 	switch (info.index) {
2115 	case VFIO_AP_REQ_IRQ_INDEX:
2116 		info.count = 1;
2117 		info.flags = VFIO_IRQ_INFO_EVENTFD;
2118 		break;
2119 	case VFIO_AP_CFG_CHG_IRQ_INDEX:
2120 		info.count = 1;
2121 		info.flags = VFIO_IRQ_INFO_EVENTFD;
2122 		break;
2123 	default:
2124 		return -EINVAL;
2125 	}
2126 
2127 	return copy_to_user((void __user *)arg, &info, minsz) ? -EFAULT : 0;
2128 }
2129 
2130 static int vfio_ap_irq_set_init(struct vfio_irq_set *irq_set, unsigned long arg)
2131 {
2132 	int ret;
2133 	size_t data_size;
2134 	unsigned long minsz;
2135 
2136 	minsz = offsetofend(struct vfio_irq_set, count);
2137 
2138 	if (copy_from_user(irq_set, (void __user *)arg, minsz))
2139 		return -EFAULT;
2140 
2141 	ret = vfio_set_irqs_validate_and_prepare(irq_set, 1, VFIO_AP_NUM_IRQS,
2142 						 &data_size);
2143 	if (ret)
2144 		return ret;
2145 
2146 	if (!(irq_set->flags & VFIO_IRQ_SET_ACTION_TRIGGER))
2147 		return -EINVAL;
2148 
2149 	return 0;
2150 }
2151 
2152 static int vfio_ap_set_request_irq(struct ap_matrix_mdev *matrix_mdev,
2153 				   unsigned long arg)
2154 {
2155 	s32 fd;
2156 	void __user *data;
2157 	unsigned long minsz;
2158 	struct eventfd_ctx *req_trigger;
2159 
2160 	minsz = offsetofend(struct vfio_irq_set, count);
2161 	data = (void __user *)(arg + minsz);
2162 
2163 	if (get_user(fd, (s32 __user *)data))
2164 		return -EFAULT;
2165 
2166 	if (fd == -1) {
2167 		if (matrix_mdev->req_trigger)
2168 			eventfd_ctx_put(matrix_mdev->req_trigger);
2169 		matrix_mdev->req_trigger = NULL;
2170 	} else if (fd >= 0) {
2171 		req_trigger = eventfd_ctx_fdget(fd);
2172 		if (IS_ERR(req_trigger))
2173 			return PTR_ERR(req_trigger);
2174 
2175 		if (matrix_mdev->req_trigger)
2176 			eventfd_ctx_put(matrix_mdev->req_trigger);
2177 
2178 		matrix_mdev->req_trigger = req_trigger;
2179 	} else {
2180 		return -EINVAL;
2181 	}
2182 
2183 	return 0;
2184 }
2185 
2186 static int vfio_ap_set_cfg_change_irq(struct ap_matrix_mdev *matrix_mdev, unsigned long arg)
2187 {
2188 	s32 fd;
2189 	void __user *data;
2190 	unsigned long minsz;
2191 	struct eventfd_ctx *cfg_chg_trigger;
2192 
2193 	minsz = offsetofend(struct vfio_irq_set, count);
2194 	data = (void __user *)(arg + minsz);
2195 
2196 	if (get_user(fd, (s32 __user *)data))
2197 		return -EFAULT;
2198 
2199 	if (fd == -1) {
2200 		if (matrix_mdev->cfg_chg_trigger)
2201 			eventfd_ctx_put(matrix_mdev->cfg_chg_trigger);
2202 		matrix_mdev->cfg_chg_trigger = NULL;
2203 	} else if (fd >= 0) {
2204 		cfg_chg_trigger = eventfd_ctx_fdget(fd);
2205 		if (IS_ERR(cfg_chg_trigger))
2206 			return PTR_ERR(cfg_chg_trigger);
2207 
2208 		if (matrix_mdev->cfg_chg_trigger)
2209 			eventfd_ctx_put(matrix_mdev->cfg_chg_trigger);
2210 
2211 		matrix_mdev->cfg_chg_trigger = cfg_chg_trigger;
2212 	} else {
2213 		return -EINVAL;
2214 	}
2215 
2216 	return 0;
2217 }
2218 
2219 static int vfio_ap_set_irqs(struct ap_matrix_mdev *matrix_mdev,
2220 			    unsigned long arg)
2221 {
2222 	int ret;
2223 	struct vfio_irq_set irq_set;
2224 
2225 	ret = vfio_ap_irq_set_init(&irq_set, arg);
2226 	if (ret)
2227 		return ret;
2228 
2229 	switch (irq_set.flags & VFIO_IRQ_SET_DATA_TYPE_MASK) {
2230 	case VFIO_IRQ_SET_DATA_EVENTFD:
2231 		switch (irq_set.index) {
2232 		case VFIO_AP_REQ_IRQ_INDEX:
2233 			return vfio_ap_set_request_irq(matrix_mdev, arg);
2234 		case VFIO_AP_CFG_CHG_IRQ_INDEX:
2235 			return vfio_ap_set_cfg_change_irq(matrix_mdev, arg);
2236 		default:
2237 			return -EINVAL;
2238 		}
2239 	default:
2240 		return -EINVAL;
2241 	}
2242 }
2243 
2244 static ssize_t vfio_ap_mdev_ioctl(struct vfio_device *vdev,
2245 				    unsigned int cmd, unsigned long arg)
2246 {
2247 	struct ap_matrix_mdev *matrix_mdev =
2248 		container_of(vdev, struct ap_matrix_mdev, vdev);
2249 	int ret;
2250 
2251 	mutex_lock(&matrix_dev->mdevs_lock);
2252 	switch (cmd) {
2253 	case VFIO_DEVICE_GET_INFO:
2254 		ret = vfio_ap_mdev_get_device_info(arg);
2255 		break;
2256 	case VFIO_DEVICE_RESET:
2257 		ret = vfio_ap_mdev_reset_queues(matrix_mdev);
2258 		break;
2259 	case VFIO_DEVICE_GET_IRQ_INFO:
2260 		ret = vfio_ap_get_irq_info(arg);
2261 		break;
2262 	case VFIO_DEVICE_SET_IRQS:
2263 		ret = vfio_ap_set_irqs(matrix_mdev, arg);
2264 		break;
2265 	default:
2266 		ret = -EOPNOTSUPP;
2267 		break;
2268 	}
2269 	mutex_unlock(&matrix_dev->mdevs_lock);
2270 
2271 	return ret;
2272 }
2273 
2274 static struct ap_matrix_mdev *vfio_ap_mdev_for_queue(struct vfio_ap_queue *q)
2275 {
2276 	struct ap_matrix_mdev *matrix_mdev;
2277 	unsigned long apid = AP_QID_CARD(q->apqn);
2278 	unsigned long apqi = AP_QID_QUEUE(q->apqn);
2279 
2280 	list_for_each_entry(matrix_mdev, &matrix_dev->mdev_list, node) {
2281 		if (test_bit_inv(apid, matrix_mdev->matrix.apm) &&
2282 		    test_bit_inv(apqi, matrix_mdev->matrix.aqm))
2283 			return matrix_mdev;
2284 	}
2285 
2286 	return NULL;
2287 }
2288 
2289 static ssize_t status_show(struct device *dev,
2290 			   struct device_attribute *attr,
2291 			   char *buf)
2292 {
2293 	ssize_t nchars = 0;
2294 	struct vfio_ap_queue *q;
2295 	unsigned long apid, apqi;
2296 	struct ap_matrix_mdev *matrix_mdev;
2297 	struct ap_device *apdev = to_ap_dev(dev);
2298 
2299 	mutex_lock(&matrix_dev->mdevs_lock);
2300 	q = dev_get_drvdata(&apdev->device);
2301 	matrix_mdev = vfio_ap_mdev_for_queue(q);
2302 
2303 	/* If the queue is assigned to the matrix mediated device, then
2304 	 * determine whether it is passed through to a guest; otherwise,
2305 	 * indicate that it is unassigned.
2306 	 */
2307 	if (matrix_mdev) {
2308 		apid = AP_QID_CARD(q->apqn);
2309 		apqi = AP_QID_QUEUE(q->apqn);
2310 		/*
2311 		 * If the queue is passed through to the guest, then indicate
2312 		 * that it is in use; otherwise, indicate that it is
2313 		 * merely assigned to a matrix mediated device.
2314 		 */
2315 		if (matrix_mdev->kvm &&
2316 		    test_bit_inv(apid, matrix_mdev->shadow_apcb.apm) &&
2317 		    test_bit_inv(apqi, matrix_mdev->shadow_apcb.aqm))
2318 			nchars = sysfs_emit(buf, "%s\n", AP_QUEUE_IN_USE);
2319 		else
2320 			nchars = sysfs_emit(buf, "%s\n", AP_QUEUE_ASSIGNED);
2321 	} else {
2322 		nchars = sysfs_emit(buf, "%s\n", AP_QUEUE_UNASSIGNED);
2323 	}
2324 
2325 	mutex_unlock(&matrix_dev->mdevs_lock);
2326 
2327 	return nchars;
2328 }
2329 
2330 static DEVICE_ATTR_RO(status);
2331 
2332 static struct attribute *vfio_queue_attrs[] = {
2333 	&dev_attr_status.attr,
2334 	NULL,
2335 };
2336 
2337 static const struct attribute_group vfio_queue_attr_group = {
2338 	.attrs = vfio_queue_attrs,
2339 };
2340 
2341 static const struct vfio_device_ops vfio_ap_matrix_dev_ops = {
2342 	.init = vfio_ap_mdev_init_dev,
2343 	.open_device = vfio_ap_mdev_open_device,
2344 	.close_device = vfio_ap_mdev_close_device,
2345 	.ioctl = vfio_ap_mdev_ioctl,
2346 	.dma_unmap = vfio_ap_mdev_dma_unmap,
2347 	.bind_iommufd = vfio_iommufd_emulated_bind,
2348 	.unbind_iommufd = vfio_iommufd_emulated_unbind,
2349 	.attach_ioas = vfio_iommufd_emulated_attach_ioas,
2350 	.detach_ioas = vfio_iommufd_emulated_detach_ioas,
2351 	.request = vfio_ap_mdev_request
2352 };
2353 
2354 static struct mdev_driver vfio_ap_matrix_driver = {
2355 	.device_api = VFIO_DEVICE_API_AP_STRING,
2356 	.max_instances = MAX_ZDEV_ENTRIES_EXT,
2357 	.driver = {
2358 		.name = "vfio_ap_mdev",
2359 		.owner = THIS_MODULE,
2360 		.mod_name = KBUILD_MODNAME,
2361 		.dev_groups = vfio_ap_mdev_attr_groups,
2362 	},
2363 	.probe = vfio_ap_mdev_probe,
2364 	.remove = vfio_ap_mdev_remove,
2365 };
2366 
2367 int vfio_ap_mdev_register(void)
2368 {
2369 	int ret;
2370 
2371 	ret = mdev_register_driver(&vfio_ap_matrix_driver);
2372 	if (ret)
2373 		return ret;
2374 
2375 	matrix_dev->mdev_type.sysfs_name = VFIO_AP_MDEV_TYPE_HWVIRT;
2376 	matrix_dev->mdev_type.pretty_name = VFIO_AP_MDEV_NAME_HWVIRT;
2377 	matrix_dev->mdev_types = &matrix_dev->mdev_type;
2378 	ret = mdev_register_parent(&matrix_dev->parent, &matrix_dev->device,
2379 				   &vfio_ap_matrix_driver,
2380 				   &matrix_dev->mdev_types, 1);
2381 	if (ret)
2382 		goto err_driver;
2383 	return 0;
2384 
2385 err_driver:
2386 	mdev_unregister_driver(&vfio_ap_matrix_driver);
2387 	return ret;
2388 }
2389 
2390 void vfio_ap_mdev_unregister(void)
2391 {
2392 	mdev_unregister_parent(&matrix_dev->parent);
2393 	mdev_unregister_driver(&vfio_ap_matrix_driver);
2394 }
2395 
2396 int vfio_ap_mdev_probe_queue(struct ap_device *apdev)
2397 {
2398 	int ret;
2399 	struct vfio_ap_queue *q;
2400 	DECLARE_BITMAP(apm_filtered, AP_DEVICES);
2401 	struct ap_matrix_mdev *matrix_mdev;
2402 
2403 	ret = sysfs_create_group(&apdev->device.kobj, &vfio_queue_attr_group);
2404 	if (ret)
2405 		return ret;
2406 
2407 	q = kzalloc(sizeof(*q), GFP_KERNEL);
2408 	if (!q) {
2409 		ret = -ENOMEM;
2410 		goto err_remove_group;
2411 	}
2412 
2413 	q->apqn = to_ap_queue(&apdev->device)->qid;
2414 	q->saved_isc = VFIO_AP_ISC_INVALID;
2415 	memset(&q->reset_status, 0, sizeof(q->reset_status));
2416 	INIT_WORK(&q->reset_work, apq_reset_check);
2417 	matrix_mdev = get_update_locks_by_apqn(q->apqn);
2418 
2419 	if (matrix_mdev) {
2420 		vfio_ap_mdev_link_queue(matrix_mdev, q);
2421 
2422 		/*
2423 		 * If we're in the process of handling the adding of adapters or
2424 		 * domains to the host's AP configuration, then let the
2425 		 * vfio_ap device driver's on_scan_complete callback filter the
2426 		 * matrix and update the guest's AP configuration after all of
2427 		 * the new queue devices are probed.
2428 		 */
2429 		if (!bitmap_empty(matrix_mdev->apm_add, AP_DEVICES) ||
2430 		    !bitmap_empty(matrix_mdev->aqm_add, AP_DOMAINS))
2431 			goto done;
2432 
2433 		if (vfio_ap_mdev_filter_matrix(matrix_mdev, apm_filtered)) {
2434 			vfio_ap_mdev_update_guest_apcb(matrix_mdev);
2435 			reset_queues_for_apids(matrix_mdev, apm_filtered);
2436 		}
2437 	}
2438 
2439 done:
2440 	dev_set_drvdata(&apdev->device, q);
2441 	release_update_locks_for_mdev(matrix_mdev);
2442 
2443 	return ret;
2444 
2445 err_remove_group:
2446 	sysfs_remove_group(&apdev->device.kobj, &vfio_queue_attr_group);
2447 	return ret;
2448 }
2449 
2450 void vfio_ap_mdev_remove_queue(struct ap_device *apdev)
2451 {
2452 	unsigned long apid, apqi;
2453 	struct vfio_ap_queue *q;
2454 	struct ap_matrix_mdev *matrix_mdev;
2455 
2456 	sysfs_remove_group(&apdev->device.kobj, &vfio_queue_attr_group);
2457 	q = dev_get_drvdata(&apdev->device);
2458 	get_update_locks_for_queue(q);
2459 	matrix_mdev = q->matrix_mdev;
2460 	apid = AP_QID_CARD(q->apqn);
2461 	apqi = AP_QID_QUEUE(q->apqn);
2462 
2463 	if (matrix_mdev) {
2464 		/* If the queue is assigned to the guest's AP configuration */
2465 		if (test_bit_inv(apid, matrix_mdev->shadow_apcb.apm) &&
2466 		    test_bit_inv(apqi, matrix_mdev->shadow_apcb.aqm)) {
2467 			/*
2468 			 * Since the queues are defined via a matrix of adapters
2469 			 * and domains, it is not possible to hot unplug a
2470 			 * single queue; so, let's unplug the adapter.
2471 			 */
2472 			clear_bit_inv(apid, matrix_mdev->shadow_apcb.apm);
2473 			vfio_ap_mdev_update_guest_apcb(matrix_mdev);
2474 			reset_queues_for_apid(matrix_mdev, apid);
2475 			goto done;
2476 		}
2477 	}
2478 
2479 	/*
2480 	 * If the queue is not in the host's AP configuration, then resetting
2481 	 * it will fail with response code 01, (APQN not valid); so, let's make
2482 	 * sure it is in the host's config.
2483 	 */
2484 	if (test_bit_inv(apid, (unsigned long *)matrix_dev->info.apm) &&
2485 	    test_bit_inv(apqi, (unsigned long *)matrix_dev->info.aqm)) {
2486 		vfio_ap_mdev_reset_queue(q);
2487 		flush_work(&q->reset_work);
2488 	}
2489 
2490 done:
2491 	if (matrix_mdev)
2492 		vfio_ap_unlink_queue_fr_mdev(q);
2493 
2494 	dev_set_drvdata(&apdev->device, NULL);
2495 	kfree(q);
2496 	release_update_locks_for_mdev(matrix_mdev);
2497 }
2498 
2499 /**
2500  * vfio_ap_mdev_resource_in_use: check whether any of a set of APQNs is
2501  *				 assigned to a mediated device under the control
2502  *				 of the vfio_ap device driver.
2503  *
2504  * @apm: a bitmap specifying a set of APIDs comprising the APQNs to check.
2505  * @aqm: a bitmap specifying a set of APQIs comprising the APQNs to check.
2506  *
2507  * Return:
2508  *	* -EADDRINUSE if one or more of the APQNs specified via @apm/@aqm are
2509  *	  assigned to a mediated device under the control of the vfio_ap
2510  *	  device driver.
2511  *	* Otherwise, return 0.
2512  */
2513 int vfio_ap_mdev_resource_in_use(unsigned long *apm, unsigned long *aqm)
2514 {
2515 	int ret;
2516 
2517 	mutex_lock(&matrix_dev->guests_lock);
2518 	mutex_lock(&matrix_dev->mdevs_lock);
2519 	ret = vfio_ap_mdev_verify_no_sharing(apm, aqm);
2520 	mutex_unlock(&matrix_dev->mdevs_lock);
2521 	mutex_unlock(&matrix_dev->guests_lock);
2522 
2523 	return ret;
2524 }
2525 
2526 /**
2527  * vfio_ap_mdev_hot_unplug_cfg - hot unplug the adapters, domains and control
2528  *				 domains that have been removed from the host's
2529  *				 AP configuration from a guest.
2530  *
2531  * @matrix_mdev: an ap_matrix_mdev object attached to a KVM guest.
2532  * @aprem: the adapters that have been removed from the host's AP configuration
2533  * @aqrem: the domains that have been removed from the host's AP configuration
2534  * @cdrem: the control domains that have been removed from the host's AP
2535  *	   configuration.
2536  */
2537 static void vfio_ap_mdev_hot_unplug_cfg(struct ap_matrix_mdev *matrix_mdev,
2538 					unsigned long *aprem,
2539 					unsigned long *aqrem,
2540 					unsigned long *cdrem)
2541 {
2542 	int do_hotplug = 0;
2543 
2544 	if (!bitmap_empty(aprem, AP_DEVICES)) {
2545 		do_hotplug |= bitmap_andnot(matrix_mdev->shadow_apcb.apm,
2546 					    matrix_mdev->shadow_apcb.apm,
2547 					    aprem, AP_DEVICES);
2548 	}
2549 
2550 	if (!bitmap_empty(aqrem, AP_DOMAINS)) {
2551 		do_hotplug |= bitmap_andnot(matrix_mdev->shadow_apcb.aqm,
2552 					    matrix_mdev->shadow_apcb.aqm,
2553 					    aqrem, AP_DEVICES);
2554 	}
2555 
2556 	if (!bitmap_empty(cdrem, AP_DOMAINS))
2557 		do_hotplug |= bitmap_andnot(matrix_mdev->shadow_apcb.adm,
2558 					    matrix_mdev->shadow_apcb.adm,
2559 					    cdrem, AP_DOMAINS);
2560 
2561 	if (do_hotplug)
2562 		vfio_ap_mdev_update_guest_apcb(matrix_mdev);
2563 }
2564 
2565 /**
2566  * vfio_ap_mdev_cfg_remove - determines which guests are using the adapters,
2567  *			     domains and control domains that have been removed
2568  *			     from the host AP configuration and unplugs them
2569  *			     from those guests.
2570  *
2571  * @ap_remove:	bitmap specifying which adapters have been removed from the host
2572  *		config.
2573  * @aq_remove:	bitmap specifying which domains have been removed from the host
2574  *		config.
2575  * @cd_remove:	bitmap specifying which control domains have been removed from
2576  *		the host config.
2577  */
2578 static void vfio_ap_mdev_cfg_remove(unsigned long *ap_remove,
2579 				    unsigned long *aq_remove,
2580 				    unsigned long *cd_remove)
2581 {
2582 	struct ap_matrix_mdev *matrix_mdev;
2583 	DECLARE_BITMAP(aprem, AP_DEVICES);
2584 	DECLARE_BITMAP(aqrem, AP_DOMAINS);
2585 	DECLARE_BITMAP(cdrem, AP_DOMAINS);
2586 	int do_remove = 0;
2587 
2588 	list_for_each_entry(matrix_mdev, &matrix_dev->mdev_list, node) {
2589 		mutex_lock(&matrix_mdev->kvm->lock);
2590 		mutex_lock(&matrix_dev->mdevs_lock);
2591 
2592 		do_remove |= bitmap_and(aprem, ap_remove,
2593 					  matrix_mdev->matrix.apm,
2594 					  AP_DEVICES);
2595 		do_remove |= bitmap_and(aqrem, aq_remove,
2596 					  matrix_mdev->matrix.aqm,
2597 					  AP_DOMAINS);
2598 		do_remove |= bitmap_andnot(cdrem, cd_remove,
2599 					     matrix_mdev->matrix.adm,
2600 					     AP_DOMAINS);
2601 
2602 		if (do_remove)
2603 			vfio_ap_mdev_hot_unplug_cfg(matrix_mdev, aprem, aqrem,
2604 						    cdrem);
2605 
2606 		mutex_unlock(&matrix_dev->mdevs_lock);
2607 		mutex_unlock(&matrix_mdev->kvm->lock);
2608 	}
2609 }
2610 
2611 /**
2612  * vfio_ap_mdev_on_cfg_remove - responds to the removal of adapters, domains and
2613  *				control domains from the host AP configuration
2614  *				by unplugging them from the guests that are
2615  *				using them.
2616  * @cur_config_info: the current host AP configuration information
2617  * @prev_config_info: the previous host AP configuration information
2618  */
2619 static void vfio_ap_mdev_on_cfg_remove(struct ap_config_info *cur_config_info,
2620 				       struct ap_config_info *prev_config_info)
2621 {
2622 	int do_remove;
2623 	DECLARE_BITMAP(aprem, AP_DEVICES);
2624 	DECLARE_BITMAP(aqrem, AP_DOMAINS);
2625 	DECLARE_BITMAP(cdrem, AP_DOMAINS);
2626 
2627 	do_remove = bitmap_andnot(aprem,
2628 				  (unsigned long *)prev_config_info->apm,
2629 				  (unsigned long *)cur_config_info->apm,
2630 				  AP_DEVICES);
2631 	do_remove |= bitmap_andnot(aqrem,
2632 				   (unsigned long *)prev_config_info->aqm,
2633 				   (unsigned long *)cur_config_info->aqm,
2634 				   AP_DEVICES);
2635 	do_remove |= bitmap_andnot(cdrem,
2636 				   (unsigned long *)prev_config_info->adm,
2637 				   (unsigned long *)cur_config_info->adm,
2638 				   AP_DEVICES);
2639 
2640 	if (do_remove)
2641 		vfio_ap_mdev_cfg_remove(aprem, aqrem, cdrem);
2642 }
2643 
2644 /**
2645  * vfio_ap_filter_apid_by_qtype: filter APIDs from an AP mask for adapters that
2646  *				 are older than AP type 10 (CEX4).
2647  * @apm: a bitmap of the APIDs to examine
2648  * @aqm: a bitmap of the APQIs of the queues to query for the AP type.
2649  */
2650 static void vfio_ap_filter_apid_by_qtype(unsigned long *apm, unsigned long *aqm)
2651 {
2652 	bool apid_cleared;
2653 	struct ap_queue_status status;
2654 	unsigned long apid, apqi;
2655 	struct ap_tapq_hwinfo info;
2656 
2657 	for_each_set_bit_inv(apid, apm, AP_DEVICES) {
2658 		apid_cleared = false;
2659 
2660 		for_each_set_bit_inv(apqi, aqm, AP_DOMAINS) {
2661 			status = ap_test_queue(AP_MKQID(apid, apqi), 1, &info);
2662 			switch (status.response_code) {
2663 			/*
2664 			 * According to the architecture in each case
2665 			 * below, the queue's info should be filled.
2666 			 */
2667 			case AP_RESPONSE_NORMAL:
2668 			case AP_RESPONSE_RESET_IN_PROGRESS:
2669 			case AP_RESPONSE_DECONFIGURED:
2670 			case AP_RESPONSE_CHECKSTOPPED:
2671 			case AP_RESPONSE_BUSY:
2672 				/*
2673 				 * The vfio_ap device driver only
2674 				 * supports CEX4 and newer adapters, so
2675 				 * remove the APID if the adapter is
2676 				 * older than a CEX4.
2677 				 */
2678 				if (info.at < AP_DEVICE_TYPE_CEX4) {
2679 					clear_bit_inv(apid, apm);
2680 					apid_cleared = true;
2681 				}
2682 
2683 				break;
2684 
2685 			default:
2686 				/*
2687 				 * If we don't know the adapter type,
2688 				 * clear its APID since it can't be
2689 				 * determined whether the vfio_ap
2690 				 * device driver supports it.
2691 				 */
2692 				clear_bit_inv(apid, apm);
2693 				apid_cleared = true;
2694 				break;
2695 			}
2696 
2697 			/*
2698 			 * If we've already cleared the APID from the apm, there
2699 			 * is no need to continue examining the remainin AP
2700 			 * queues to determine the type of the adapter.
2701 			 */
2702 			if (apid_cleared)
2703 				continue;
2704 		}
2705 	}
2706 }
2707 
2708 /**
2709  * vfio_ap_mdev_cfg_add - store bitmaps specifying the adapters, domains and
2710  *			  control domains that have been added to the host's
2711  *			  AP configuration for each matrix mdev to which they
2712  *			  are assigned.
2713  *
2714  * @apm_add: a bitmap specifying the adapters that have been added to the AP
2715  *	     configuration.
2716  * @aqm_add: a bitmap specifying the domains that have been added to the AP
2717  *	     configuration.
2718  * @adm_add: a bitmap specifying the control domains that have been added to the
2719  *	     AP configuration.
2720  */
2721 static void vfio_ap_mdev_cfg_add(unsigned long *apm_add, unsigned long *aqm_add,
2722 				 unsigned long *adm_add)
2723 {
2724 	struct ap_matrix_mdev *matrix_mdev;
2725 
2726 	if (list_empty(&matrix_dev->mdev_list))
2727 		return;
2728 
2729 	vfio_ap_filter_apid_by_qtype(apm_add, aqm_add);
2730 
2731 	list_for_each_entry(matrix_mdev, &matrix_dev->mdev_list, node) {
2732 		bitmap_and(matrix_mdev->apm_add,
2733 			   matrix_mdev->matrix.apm, apm_add, AP_DEVICES);
2734 		bitmap_and(matrix_mdev->aqm_add,
2735 			   matrix_mdev->matrix.aqm, aqm_add, AP_DOMAINS);
2736 		bitmap_and(matrix_mdev->adm_add,
2737 			   matrix_mdev->matrix.adm, adm_add, AP_DEVICES);
2738 	}
2739 }
2740 
2741 /**
2742  * vfio_ap_mdev_on_cfg_add - responds to the addition of adapters, domains and
2743  *			     control domains to the host AP configuration
2744  *			     by updating the bitmaps that specify what adapters,
2745  *			     domains and control domains have been added so they
2746  *			     can be hot plugged into the guest when the AP bus
2747  *			     scan completes (see vfio_ap_on_scan_complete
2748  *			     function).
2749  * @cur_config_info: the current AP configuration information
2750  * @prev_config_info: the previous AP configuration information
2751  */
2752 static void vfio_ap_mdev_on_cfg_add(struct ap_config_info *cur_config_info,
2753 				    struct ap_config_info *prev_config_info)
2754 {
2755 	bool do_add;
2756 	DECLARE_BITMAP(apm_add, AP_DEVICES);
2757 	DECLARE_BITMAP(aqm_add, AP_DOMAINS);
2758 	DECLARE_BITMAP(adm_add, AP_DOMAINS);
2759 
2760 	do_add = bitmap_andnot(apm_add,
2761 			       (unsigned long *)cur_config_info->apm,
2762 			       (unsigned long *)prev_config_info->apm,
2763 			       AP_DEVICES);
2764 	do_add |= bitmap_andnot(aqm_add,
2765 				(unsigned long *)cur_config_info->aqm,
2766 				(unsigned long *)prev_config_info->aqm,
2767 				AP_DOMAINS);
2768 	do_add |= bitmap_andnot(adm_add,
2769 				(unsigned long *)cur_config_info->adm,
2770 				(unsigned long *)prev_config_info->adm,
2771 				AP_DOMAINS);
2772 
2773 	if (do_add)
2774 		vfio_ap_mdev_cfg_add(apm_add, aqm_add, adm_add);
2775 }
2776 
2777 /**
2778  * vfio_ap_on_cfg_changed - handles notification of changes to the host AP
2779  *			    configuration.
2780  *
2781  * @cur_cfg_info: the current host AP configuration
2782  * @prev_cfg_info: the previous host AP configuration
2783  */
2784 void vfio_ap_on_cfg_changed(struct ap_config_info *cur_cfg_info,
2785 			    struct ap_config_info *prev_cfg_info)
2786 {
2787 	if (!cur_cfg_info || !prev_cfg_info)
2788 		return;
2789 
2790 	mutex_lock(&matrix_dev->guests_lock);
2791 
2792 	vfio_ap_mdev_on_cfg_remove(cur_cfg_info, prev_cfg_info);
2793 	vfio_ap_mdev_on_cfg_add(cur_cfg_info, prev_cfg_info);
2794 	memcpy(&matrix_dev->info, cur_cfg_info, sizeof(*cur_cfg_info));
2795 
2796 	mutex_unlock(&matrix_dev->guests_lock);
2797 }
2798 
2799 static void vfio_ap_mdev_hot_plug_cfg(struct ap_matrix_mdev *matrix_mdev)
2800 {
2801 	DECLARE_BITMAP(apm_filtered, AP_DEVICES);
2802 	bool filter_domains, filter_adapters, filter_cdoms, do_hotplug = false;
2803 
2804 	mutex_lock(&matrix_mdev->kvm->lock);
2805 	mutex_lock(&matrix_dev->mdevs_lock);
2806 
2807 	filter_adapters = bitmap_intersects(matrix_mdev->matrix.apm,
2808 					    matrix_mdev->apm_add, AP_DEVICES);
2809 	filter_domains = bitmap_intersects(matrix_mdev->matrix.aqm,
2810 					   matrix_mdev->aqm_add, AP_DOMAINS);
2811 	filter_cdoms = bitmap_intersects(matrix_mdev->matrix.adm,
2812 					 matrix_mdev->adm_add, AP_DOMAINS);
2813 
2814 	if (filter_adapters || filter_domains)
2815 		do_hotplug = vfio_ap_mdev_filter_matrix(matrix_mdev, apm_filtered);
2816 
2817 	if (filter_cdoms)
2818 		do_hotplug |= vfio_ap_mdev_filter_cdoms(matrix_mdev);
2819 
2820 	if (do_hotplug)
2821 		vfio_ap_mdev_update_guest_apcb(matrix_mdev);
2822 
2823 	reset_queues_for_apids(matrix_mdev, apm_filtered);
2824 
2825 	mutex_unlock(&matrix_dev->mdevs_lock);
2826 	mutex_unlock(&matrix_mdev->kvm->lock);
2827 }
2828 
2829 void vfio_ap_on_scan_complete(struct ap_config_info *new_config_info,
2830 			      struct ap_config_info *old_config_info)
2831 {
2832 	struct ap_matrix_mdev *matrix_mdev;
2833 
2834 	mutex_lock(&matrix_dev->guests_lock);
2835 
2836 	list_for_each_entry(matrix_mdev, &matrix_dev->mdev_list, node) {
2837 		if (bitmap_empty(matrix_mdev->apm_add, AP_DEVICES) &&
2838 		    bitmap_empty(matrix_mdev->aqm_add, AP_DOMAINS) &&
2839 		    bitmap_empty(matrix_mdev->adm_add, AP_DOMAINS))
2840 			continue;
2841 
2842 		vfio_ap_mdev_hot_plug_cfg(matrix_mdev);
2843 		bitmap_clear(matrix_mdev->apm_add, 0, AP_DEVICES);
2844 		bitmap_clear(matrix_mdev->aqm_add, 0, AP_DOMAINS);
2845 		bitmap_clear(matrix_mdev->adm_add, 0, AP_DOMAINS);
2846 	}
2847 
2848 	mutex_unlock(&matrix_dev->guests_lock);
2849 }
2850