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 <asm/kvm.h>
20 #include <asm/zcrypt.h>
21
22 #include "vfio_ap_private.h"
23
24 #define VFIO_AP_MDEV_TYPE_HWVIRT "passthrough"
25 #define VFIO_AP_MDEV_NAME_HWVIRT "VFIO AP Passthrough Device"
26
27 static int vfio_ap_mdev_reset_queues(struct ap_matrix_mdev *matrix_mdev);
28 static struct vfio_ap_queue *vfio_ap_find_queue(int apqn);
29 static const struct vfio_device_ops vfio_ap_matrix_dev_ops;
30
match_apqn(struct device * dev,const void * data)31 static int match_apqn(struct device *dev, const void *data)
32 {
33 struct vfio_ap_queue *q = dev_get_drvdata(dev);
34
35 return (q->apqn == *(int *)(data)) ? 1 : 0;
36 }
37
38 /**
39 * vfio_ap_get_queue - retrieve a queue with a specific APQN from a list
40 * @matrix_mdev: the associated mediated matrix
41 * @apqn: The queue APQN
42 *
43 * Retrieve a queue with a specific APQN from the list of the
44 * devices of the vfio_ap_drv.
45 * Verify that the APID and the APQI are set in the matrix.
46 *
47 * Return: the pointer to the associated vfio_ap_queue
48 */
vfio_ap_get_queue(struct ap_matrix_mdev * matrix_mdev,int apqn)49 static struct vfio_ap_queue *vfio_ap_get_queue(
50 struct ap_matrix_mdev *matrix_mdev,
51 int apqn)
52 {
53 struct vfio_ap_queue *q;
54
55 if (!test_bit_inv(AP_QID_CARD(apqn), matrix_mdev->matrix.apm))
56 return NULL;
57 if (!test_bit_inv(AP_QID_QUEUE(apqn), matrix_mdev->matrix.aqm))
58 return NULL;
59
60 q = vfio_ap_find_queue(apqn);
61 if (q)
62 q->matrix_mdev = matrix_mdev;
63
64 return q;
65 }
66
67 /**
68 * vfio_ap_wait_for_irqclear - clears the IR bit or gives up after 5 tries
69 * @apqn: The AP Queue number
70 *
71 * Checks the IRQ bit for the status of this APQN using ap_tapq.
72 * Returns if the ap_tapq function succeeded and the bit is clear.
73 * Returns if ap_tapq function failed with invalid, deconfigured or
74 * checkstopped AP.
75 * Otherwise retries up to 5 times after waiting 20ms.
76 */
vfio_ap_wait_for_irqclear(int apqn)77 static void vfio_ap_wait_for_irqclear(int apqn)
78 {
79 struct ap_queue_status status;
80 int retry = 5;
81
82 do {
83 status = ap_tapq(apqn, NULL);
84 switch (status.response_code) {
85 case AP_RESPONSE_NORMAL:
86 case AP_RESPONSE_RESET_IN_PROGRESS:
87 if (!status.irq_enabled)
88 return;
89 fallthrough;
90 case AP_RESPONSE_BUSY:
91 msleep(20);
92 break;
93 case AP_RESPONSE_Q_NOT_AVAIL:
94 case AP_RESPONSE_DECONFIGURED:
95 case AP_RESPONSE_CHECKSTOPPED:
96 default:
97 WARN_ONCE(1, "%s: tapq rc %02x: %04x\n", __func__,
98 status.response_code, apqn);
99 return;
100 }
101 } while (--retry);
102
103 WARN_ONCE(1, "%s: tapq rc %02x: %04x could not clear IR bit\n",
104 __func__, status.response_code, apqn);
105 }
106
107 /**
108 * vfio_ap_free_aqic_resources - free vfio_ap_queue resources
109 * @q: The vfio_ap_queue
110 *
111 * Unregisters the ISC in the GIB when the saved ISC not invalid.
112 * Unpins the guest's page holding the NIB when it exists.
113 * Resets the saved_pfn and saved_isc to invalid values.
114 */
vfio_ap_free_aqic_resources(struct vfio_ap_queue * q)115 static void vfio_ap_free_aqic_resources(struct vfio_ap_queue *q)
116 {
117 if (!q)
118 return;
119 if (q->saved_isc != VFIO_AP_ISC_INVALID &&
120 !WARN_ON(!(q->matrix_mdev && q->matrix_mdev->kvm))) {
121 kvm_s390_gisc_unregister(q->matrix_mdev->kvm, q->saved_isc);
122 q->saved_isc = VFIO_AP_ISC_INVALID;
123 }
124 if (q->saved_pfn && !WARN_ON(!q->matrix_mdev)) {
125 vfio_unpin_pages(mdev_dev(q->matrix_mdev->mdev),
126 &q->saved_pfn, 1);
127 q->saved_pfn = 0;
128 }
129 }
130
131 /**
132 * vfio_ap_irq_disable - disables and clears an ap_queue interrupt
133 * @q: The vfio_ap_queue
134 *
135 * Uses ap_aqic to disable the interruption and in case of success, reset
136 * in progress or IRQ disable command already proceeded: calls
137 * vfio_ap_wait_for_irqclear() to check for the IRQ bit to be clear
138 * and calls vfio_ap_free_aqic_resources() to free the resources associated
139 * with the AP interrupt handling.
140 *
141 * In the case the AP is busy, or a reset is in progress,
142 * retries after 20ms, up to 5 times.
143 *
144 * Returns if ap_aqic function failed with invalid, deconfigured or
145 * checkstopped AP.
146 *
147 * Return: &struct ap_queue_status
148 */
vfio_ap_irq_disable(struct vfio_ap_queue * q)149 static struct ap_queue_status vfio_ap_irq_disable(struct vfio_ap_queue *q)
150 {
151 struct ap_qirq_ctrl aqic_gisa = {};
152 struct ap_queue_status status;
153 int retries = 5;
154
155 do {
156 status = ap_aqic(q->apqn, aqic_gisa, NULL);
157 switch (status.response_code) {
158 case AP_RESPONSE_OTHERWISE_CHANGED:
159 case AP_RESPONSE_NORMAL:
160 vfio_ap_wait_for_irqclear(q->apqn);
161 goto end_free;
162 case AP_RESPONSE_RESET_IN_PROGRESS:
163 case AP_RESPONSE_BUSY:
164 msleep(20);
165 break;
166 case AP_RESPONSE_Q_NOT_AVAIL:
167 case AP_RESPONSE_DECONFIGURED:
168 case AP_RESPONSE_CHECKSTOPPED:
169 case AP_RESPONSE_INVALID_ADDRESS:
170 default:
171 /* All cases in default means AP not operational */
172 WARN_ONCE(1, "%s: ap_aqic status %d\n", __func__,
173 status.response_code);
174 goto end_free;
175 }
176 } while (retries--);
177
178 WARN_ONCE(1, "%s: ap_aqic status %d\n", __func__,
179 status.response_code);
180 end_free:
181 vfio_ap_free_aqic_resources(q);
182 q->matrix_mdev = NULL;
183 return status;
184 }
185
186 /**
187 * vfio_ap_irq_enable - Enable Interruption for a APQN
188 *
189 * @q: the vfio_ap_queue holding AQIC parameters
190 *
191 * Pin the NIB saved in *q
192 * Register the guest ISC to GIB interface and retrieve the
193 * host ISC to issue the host side PQAP/AQIC
194 *
195 * Response.status may be set to AP_RESPONSE_INVALID_ADDRESS in case the
196 * vfio_pin_pages failed.
197 *
198 * Otherwise return the ap_queue_status returned by the ap_aqic(),
199 * all retry handling will be done by the guest.
200 *
201 * Return: &struct ap_queue_status
202 */
vfio_ap_irq_enable(struct vfio_ap_queue * q,int isc,unsigned long nib)203 static struct ap_queue_status vfio_ap_irq_enable(struct vfio_ap_queue *q,
204 int isc,
205 unsigned long nib)
206 {
207 struct ap_qirq_ctrl aqic_gisa = {};
208 struct ap_queue_status status = {};
209 struct kvm_s390_gisa *gisa;
210 struct kvm *kvm;
211 unsigned long h_nib, g_pfn, h_pfn;
212 int ret;
213
214 g_pfn = nib >> PAGE_SHIFT;
215 ret = vfio_pin_pages(mdev_dev(q->matrix_mdev->mdev), &g_pfn, 1,
216 IOMMU_READ | IOMMU_WRITE, &h_pfn);
217 switch (ret) {
218 case 1:
219 break;
220 default:
221 status.response_code = AP_RESPONSE_INVALID_ADDRESS;
222 return status;
223 }
224
225 kvm = q->matrix_mdev->kvm;
226 gisa = kvm->arch.gisa_int.origin;
227
228 h_nib = (h_pfn << PAGE_SHIFT) | (nib & ~PAGE_MASK);
229 aqic_gisa.gisc = isc;
230 aqic_gisa.isc = kvm_s390_gisc_register(kvm, isc);
231 aqic_gisa.ir = 1;
232 aqic_gisa.gisa = (uint64_t)gisa >> 4;
233
234 status = ap_aqic(q->apqn, aqic_gisa, (void *)h_nib);
235 switch (status.response_code) {
236 case AP_RESPONSE_NORMAL:
237 /* See if we did clear older IRQ configuration */
238 vfio_ap_free_aqic_resources(q);
239 q->saved_pfn = g_pfn;
240 q->saved_isc = isc;
241 break;
242 case AP_RESPONSE_OTHERWISE_CHANGED:
243 /* We could not modify IRQ setings: clear new configuration */
244 vfio_unpin_pages(mdev_dev(q->matrix_mdev->mdev), &g_pfn, 1);
245 kvm_s390_gisc_unregister(kvm, isc);
246 break;
247 default:
248 pr_warn("%s: apqn %04x: response: %02x\n", __func__, q->apqn,
249 status.response_code);
250 vfio_ap_irq_disable(q);
251 break;
252 }
253
254 return status;
255 }
256
257 /**
258 * handle_pqap - PQAP instruction callback
259 *
260 * @vcpu: The vcpu on which we received the PQAP instruction
261 *
262 * Get the general register contents to initialize internal variables.
263 * REG[0]: APQN
264 * REG[1]: IR and ISC
265 * REG[2]: NIB
266 *
267 * Response.status may be set to following Response Code:
268 * - AP_RESPONSE_Q_NOT_AVAIL: if the queue is not available
269 * - AP_RESPONSE_DECONFIGURED: if the queue is not configured
270 * - AP_RESPONSE_NORMAL (0) : in case of successs
271 * Check vfio_ap_setirq() and vfio_ap_clrirq() for other possible RC.
272 * We take the matrix_dev lock to ensure serialization on queues and
273 * mediated device access.
274 *
275 * Return: 0 if we could handle the request inside KVM.
276 * Otherwise, returns -EOPNOTSUPP to let QEMU handle the fault.
277 */
handle_pqap(struct kvm_vcpu * vcpu)278 static int handle_pqap(struct kvm_vcpu *vcpu)
279 {
280 uint64_t status;
281 uint16_t apqn;
282 struct vfio_ap_queue *q;
283 struct ap_queue_status qstatus = {
284 .response_code = AP_RESPONSE_Q_NOT_AVAIL, };
285 struct ap_matrix_mdev *matrix_mdev;
286
287 /* If we do not use the AIV facility just go to userland */
288 if (!(vcpu->arch.sie_block->eca & ECA_AIV))
289 return -EOPNOTSUPP;
290
291 apqn = vcpu->run->s.regs.gprs[0] & 0xffff;
292 mutex_lock(&matrix_dev->lock);
293
294 if (!vcpu->kvm->arch.crypto.pqap_hook)
295 goto out_unlock;
296 matrix_mdev = container_of(vcpu->kvm->arch.crypto.pqap_hook,
297 struct ap_matrix_mdev, pqap_hook);
298
299 /* If the there is no guest using the mdev, there is nothing to do */
300 if (!matrix_mdev->kvm)
301 goto out_unlock;
302
303 q = vfio_ap_get_queue(matrix_mdev, apqn);
304 if (!q)
305 goto out_unlock;
306
307 status = vcpu->run->s.regs.gprs[1];
308
309 /* If IR bit(16) is set we enable the interrupt */
310 if ((status >> (63 - 16)) & 0x01)
311 qstatus = vfio_ap_irq_enable(q, status & 0x07,
312 vcpu->run->s.regs.gprs[2]);
313 else
314 qstatus = vfio_ap_irq_disable(q);
315
316 out_unlock:
317 memcpy(&vcpu->run->s.regs.gprs[1], &qstatus, sizeof(qstatus));
318 vcpu->run->s.regs.gprs[1] >>= 32;
319 mutex_unlock(&matrix_dev->lock);
320 return 0;
321 }
322
vfio_ap_matrix_init(struct ap_config_info * info,struct ap_matrix * matrix)323 static void vfio_ap_matrix_init(struct ap_config_info *info,
324 struct ap_matrix *matrix)
325 {
326 matrix->apm_max = info->apxa ? info->Na : 63;
327 matrix->aqm_max = info->apxa ? info->Nd : 15;
328 matrix->adm_max = info->apxa ? info->Nd : 15;
329 }
330
vfio_ap_mdev_probe(struct mdev_device * mdev)331 static int vfio_ap_mdev_probe(struct mdev_device *mdev)
332 {
333 struct ap_matrix_mdev *matrix_mdev;
334 int ret;
335
336 if ((atomic_dec_if_positive(&matrix_dev->available_instances) < 0))
337 return -EPERM;
338
339 matrix_mdev = kzalloc(sizeof(*matrix_mdev), GFP_KERNEL);
340 if (!matrix_mdev) {
341 ret = -ENOMEM;
342 goto err_dec_available;
343 }
344 vfio_init_group_dev(&matrix_mdev->vdev, &mdev->dev,
345 &vfio_ap_matrix_dev_ops);
346
347 matrix_mdev->mdev = mdev;
348 vfio_ap_matrix_init(&matrix_dev->info, &matrix_mdev->matrix);
349 matrix_mdev->pqap_hook = handle_pqap;
350 mutex_lock(&matrix_dev->lock);
351 list_add(&matrix_mdev->node, &matrix_dev->mdev_list);
352 mutex_unlock(&matrix_dev->lock);
353
354 ret = vfio_register_group_dev(&matrix_mdev->vdev);
355 if (ret)
356 goto err_list;
357 dev_set_drvdata(&mdev->dev, matrix_mdev);
358 return 0;
359
360 err_list:
361 mutex_lock(&matrix_dev->lock);
362 list_del(&matrix_mdev->node);
363 mutex_unlock(&matrix_dev->lock);
364 vfio_uninit_group_dev(&matrix_mdev->vdev);
365 kfree(matrix_mdev);
366 err_dec_available:
367 atomic_inc(&matrix_dev->available_instances);
368 return ret;
369 }
370
vfio_ap_mdev_remove(struct mdev_device * mdev)371 static void vfio_ap_mdev_remove(struct mdev_device *mdev)
372 {
373 struct ap_matrix_mdev *matrix_mdev = dev_get_drvdata(&mdev->dev);
374
375 vfio_unregister_group_dev(&matrix_mdev->vdev);
376
377 mutex_lock(&matrix_dev->lock);
378 vfio_ap_mdev_reset_queues(matrix_mdev);
379 list_del(&matrix_mdev->node);
380 mutex_unlock(&matrix_dev->lock);
381 vfio_uninit_group_dev(&matrix_mdev->vdev);
382 kfree(matrix_mdev);
383 atomic_inc(&matrix_dev->available_instances);
384 }
385
name_show(struct mdev_type * mtype,struct mdev_type_attribute * attr,char * buf)386 static ssize_t name_show(struct mdev_type *mtype,
387 struct mdev_type_attribute *attr, char *buf)
388 {
389 return sprintf(buf, "%s\n", VFIO_AP_MDEV_NAME_HWVIRT);
390 }
391
392 static MDEV_TYPE_ATTR_RO(name);
393
available_instances_show(struct mdev_type * mtype,struct mdev_type_attribute * attr,char * buf)394 static ssize_t available_instances_show(struct mdev_type *mtype,
395 struct mdev_type_attribute *attr,
396 char *buf)
397 {
398 return sprintf(buf, "%d\n",
399 atomic_read(&matrix_dev->available_instances));
400 }
401
402 static MDEV_TYPE_ATTR_RO(available_instances);
403
device_api_show(struct mdev_type * mtype,struct mdev_type_attribute * attr,char * buf)404 static ssize_t device_api_show(struct mdev_type *mtype,
405 struct mdev_type_attribute *attr, char *buf)
406 {
407 return sprintf(buf, "%s\n", VFIO_DEVICE_API_AP_STRING);
408 }
409
410 static MDEV_TYPE_ATTR_RO(device_api);
411
412 static struct attribute *vfio_ap_mdev_type_attrs[] = {
413 &mdev_type_attr_name.attr,
414 &mdev_type_attr_device_api.attr,
415 &mdev_type_attr_available_instances.attr,
416 NULL,
417 };
418
419 static struct attribute_group vfio_ap_mdev_hwvirt_type_group = {
420 .name = VFIO_AP_MDEV_TYPE_HWVIRT,
421 .attrs = vfio_ap_mdev_type_attrs,
422 };
423
424 static struct attribute_group *vfio_ap_mdev_type_groups[] = {
425 &vfio_ap_mdev_hwvirt_type_group,
426 NULL,
427 };
428
429 struct vfio_ap_queue_reserved {
430 unsigned long *apid;
431 unsigned long *apqi;
432 bool reserved;
433 };
434
435 /**
436 * vfio_ap_has_queue - determines if the AP queue containing the target in @data
437 *
438 * @dev: an AP queue device
439 * @data: a struct vfio_ap_queue_reserved reference
440 *
441 * Flags whether the AP queue device (@dev) has a queue ID containing the APQN,
442 * apid or apqi specified in @data:
443 *
444 * - If @data contains both an apid and apqi value, then @data will be flagged
445 * as reserved if the APID and APQI fields for the AP queue device matches
446 *
447 * - If @data contains only an apid value, @data will be flagged as
448 * reserved if the APID field in the AP queue device matches
449 *
450 * - If @data contains only an apqi value, @data will be flagged as
451 * reserved if the APQI field in the AP queue device matches
452 *
453 * Return: 0 to indicate the input to function succeeded. Returns -EINVAL if
454 * @data does not contain either an apid or apqi.
455 */
vfio_ap_has_queue(struct device * dev,void * data)456 static int vfio_ap_has_queue(struct device *dev, void *data)
457 {
458 struct vfio_ap_queue_reserved *qres = data;
459 struct ap_queue *ap_queue = to_ap_queue(dev);
460 ap_qid_t qid;
461 unsigned long id;
462
463 if (qres->apid && qres->apqi) {
464 qid = AP_MKQID(*qres->apid, *qres->apqi);
465 if (qid == ap_queue->qid)
466 qres->reserved = true;
467 } else if (qres->apid && !qres->apqi) {
468 id = AP_QID_CARD(ap_queue->qid);
469 if (id == *qres->apid)
470 qres->reserved = true;
471 } else if (!qres->apid && qres->apqi) {
472 id = AP_QID_QUEUE(ap_queue->qid);
473 if (id == *qres->apqi)
474 qres->reserved = true;
475 } else {
476 return -EINVAL;
477 }
478
479 return 0;
480 }
481
482 /**
483 * vfio_ap_verify_queue_reserved - verifies that the AP queue containing
484 * @apid or @aqpi is reserved
485 *
486 * @apid: an AP adapter ID
487 * @apqi: an AP queue index
488 *
489 * Verifies that the AP queue with @apid/@apqi is reserved by the VFIO AP device
490 * driver according to the following rules:
491 *
492 * - If both @apid and @apqi are not NULL, then there must be an AP queue
493 * device bound to the vfio_ap driver with the APQN identified by @apid and
494 * @apqi
495 *
496 * - If only @apid is not NULL, then there must be an AP queue device bound
497 * to the vfio_ap driver with an APQN containing @apid
498 *
499 * - If only @apqi is not NULL, then there must be an AP queue device bound
500 * to the vfio_ap driver with an APQN containing @apqi
501 *
502 * Return: 0 if the AP queue is reserved; otherwise, returns -EADDRNOTAVAIL.
503 */
vfio_ap_verify_queue_reserved(unsigned long * apid,unsigned long * apqi)504 static int vfio_ap_verify_queue_reserved(unsigned long *apid,
505 unsigned long *apqi)
506 {
507 int ret;
508 struct vfio_ap_queue_reserved qres;
509
510 qres.apid = apid;
511 qres.apqi = apqi;
512 qres.reserved = false;
513
514 ret = driver_for_each_device(&matrix_dev->vfio_ap_drv->driver, NULL,
515 &qres, vfio_ap_has_queue);
516 if (ret)
517 return ret;
518
519 if (qres.reserved)
520 return 0;
521
522 return -EADDRNOTAVAIL;
523 }
524
525 static int
vfio_ap_mdev_verify_queues_reserved_for_apid(struct ap_matrix_mdev * matrix_mdev,unsigned long apid)526 vfio_ap_mdev_verify_queues_reserved_for_apid(struct ap_matrix_mdev *matrix_mdev,
527 unsigned long apid)
528 {
529 int ret;
530 unsigned long apqi;
531 unsigned long nbits = matrix_mdev->matrix.aqm_max + 1;
532
533 if (find_first_bit_inv(matrix_mdev->matrix.aqm, nbits) >= nbits)
534 return vfio_ap_verify_queue_reserved(&apid, NULL);
535
536 for_each_set_bit_inv(apqi, matrix_mdev->matrix.aqm, nbits) {
537 ret = vfio_ap_verify_queue_reserved(&apid, &apqi);
538 if (ret)
539 return ret;
540 }
541
542 return 0;
543 }
544
545 /**
546 * vfio_ap_mdev_verify_no_sharing - verifies that the AP matrix is not configured
547 *
548 * @matrix_mdev: the mediated matrix device
549 *
550 * Verifies that the APQNs derived from the cross product of the AP adapter IDs
551 * and AP queue indexes comprising the AP matrix are not configured for another
552 * mediated device. AP queue sharing is not allowed.
553 *
554 * Return: 0 if the APQNs are not shared; otherwise returns -EADDRINUSE.
555 */
vfio_ap_mdev_verify_no_sharing(struct ap_matrix_mdev * matrix_mdev)556 static int vfio_ap_mdev_verify_no_sharing(struct ap_matrix_mdev *matrix_mdev)
557 {
558 struct ap_matrix_mdev *lstdev;
559 DECLARE_BITMAP(apm, AP_DEVICES);
560 DECLARE_BITMAP(aqm, AP_DOMAINS);
561
562 list_for_each_entry(lstdev, &matrix_dev->mdev_list, node) {
563 if (matrix_mdev == lstdev)
564 continue;
565
566 memset(apm, 0, sizeof(apm));
567 memset(aqm, 0, sizeof(aqm));
568
569 /*
570 * We work on full longs, as we can only exclude the leftover
571 * bits in non-inverse order. The leftover is all zeros.
572 */
573 if (!bitmap_and(apm, matrix_mdev->matrix.apm,
574 lstdev->matrix.apm, AP_DEVICES))
575 continue;
576
577 if (!bitmap_and(aqm, matrix_mdev->matrix.aqm,
578 lstdev->matrix.aqm, AP_DOMAINS))
579 continue;
580
581 return -EADDRINUSE;
582 }
583
584 return 0;
585 }
586
587 /**
588 * assign_adapter_store - parses the APID from @buf and sets the
589 * corresponding bit in the mediated matrix device's APM
590 *
591 * @dev: the matrix device
592 * @attr: the mediated matrix device's assign_adapter attribute
593 * @buf: a buffer containing the AP adapter number (APID) to
594 * be assigned
595 * @count: the number of bytes in @buf
596 *
597 * Return: the number of bytes processed if the APID is valid; otherwise,
598 * returns one of the following errors:
599 *
600 * 1. -EINVAL
601 * The APID is not a valid number
602 *
603 * 2. -ENODEV
604 * The APID exceeds the maximum value configured for the system
605 *
606 * 3. -EADDRNOTAVAIL
607 * An APQN derived from the cross product of the APID being assigned
608 * and the APQIs previously assigned is not bound to the vfio_ap device
609 * driver; or, if no APQIs have yet been assigned, the APID is not
610 * contained in an APQN bound to the vfio_ap device driver.
611 *
612 * 4. -EADDRINUSE
613 * An APQN derived from the cross product of the APID being assigned
614 * and the APQIs previously assigned is being used by another mediated
615 * matrix device
616 */
assign_adapter_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)617 static ssize_t assign_adapter_store(struct device *dev,
618 struct device_attribute *attr,
619 const char *buf, size_t count)
620 {
621 int ret;
622 unsigned long apid;
623 struct ap_matrix_mdev *matrix_mdev = dev_get_drvdata(dev);
624
625 mutex_lock(&matrix_dev->lock);
626
627 /* If the KVM guest is running, disallow assignment of adapter */
628 if (matrix_mdev->kvm) {
629 ret = -EBUSY;
630 goto done;
631 }
632
633 ret = kstrtoul(buf, 0, &apid);
634 if (ret)
635 goto done;
636
637 if (apid > matrix_mdev->matrix.apm_max) {
638 ret = -ENODEV;
639 goto done;
640 }
641
642 /*
643 * Set the bit in the AP mask (APM) corresponding to the AP adapter
644 * number (APID). The bits in the mask, from most significant to least
645 * significant bit, correspond to APIDs 0-255.
646 */
647 ret = vfio_ap_mdev_verify_queues_reserved_for_apid(matrix_mdev, apid);
648 if (ret)
649 goto done;
650
651 set_bit_inv(apid, matrix_mdev->matrix.apm);
652
653 ret = vfio_ap_mdev_verify_no_sharing(matrix_mdev);
654 if (ret)
655 goto share_err;
656
657 ret = count;
658 goto done;
659
660 share_err:
661 clear_bit_inv(apid, matrix_mdev->matrix.apm);
662 done:
663 mutex_unlock(&matrix_dev->lock);
664
665 return ret;
666 }
667 static DEVICE_ATTR_WO(assign_adapter);
668
669 /**
670 * unassign_adapter_store - parses the APID from @buf and clears the
671 * corresponding bit in the mediated matrix device's APM
672 *
673 * @dev: the matrix device
674 * @attr: the mediated matrix device's unassign_adapter attribute
675 * @buf: a buffer containing the adapter number (APID) to be unassigned
676 * @count: the number of bytes in @buf
677 *
678 * Return: the number of bytes processed if the APID is valid; otherwise,
679 * returns one of the following errors:
680 * -EINVAL if the APID is not a number
681 * -ENODEV if the APID it exceeds the maximum value configured for the
682 * system
683 */
unassign_adapter_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)684 static ssize_t unassign_adapter_store(struct device *dev,
685 struct device_attribute *attr,
686 const char *buf, size_t count)
687 {
688 int ret;
689 unsigned long apid;
690 struct ap_matrix_mdev *matrix_mdev = dev_get_drvdata(dev);
691
692 mutex_lock(&matrix_dev->lock);
693
694 /* If the KVM guest is running, disallow unassignment of adapter */
695 if (matrix_mdev->kvm) {
696 ret = -EBUSY;
697 goto done;
698 }
699
700 ret = kstrtoul(buf, 0, &apid);
701 if (ret)
702 goto done;
703
704 if (apid > matrix_mdev->matrix.apm_max) {
705 ret = -ENODEV;
706 goto done;
707 }
708
709 clear_bit_inv((unsigned long)apid, matrix_mdev->matrix.apm);
710 ret = count;
711 done:
712 mutex_unlock(&matrix_dev->lock);
713 return ret;
714 }
715 static DEVICE_ATTR_WO(unassign_adapter);
716
717 static int
vfio_ap_mdev_verify_queues_reserved_for_apqi(struct ap_matrix_mdev * matrix_mdev,unsigned long apqi)718 vfio_ap_mdev_verify_queues_reserved_for_apqi(struct ap_matrix_mdev *matrix_mdev,
719 unsigned long apqi)
720 {
721 int ret;
722 unsigned long apid;
723 unsigned long nbits = matrix_mdev->matrix.apm_max + 1;
724
725 if (find_first_bit_inv(matrix_mdev->matrix.apm, nbits) >= nbits)
726 return vfio_ap_verify_queue_reserved(NULL, &apqi);
727
728 for_each_set_bit_inv(apid, matrix_mdev->matrix.apm, nbits) {
729 ret = vfio_ap_verify_queue_reserved(&apid, &apqi);
730 if (ret)
731 return ret;
732 }
733
734 return 0;
735 }
736
737 /**
738 * assign_domain_store - parses the APQI from @buf and sets the
739 * corresponding bit in the mediated matrix device's AQM
740 *
741 *
742 * @dev: the matrix device
743 * @attr: the mediated matrix device's assign_domain attribute
744 * @buf: a buffer containing the AP queue index (APQI) of the domain to
745 * be assigned
746 * @count: the number of bytes in @buf
747 *
748 * Return: the number of bytes processed if the APQI is valid; otherwise returns
749 * one of the following errors:
750 *
751 * 1. -EINVAL
752 * The APQI is not a valid number
753 *
754 * 2. -ENODEV
755 * The APQI exceeds the maximum value configured for the system
756 *
757 * 3. -EADDRNOTAVAIL
758 * An APQN derived from the cross product of the APQI being assigned
759 * and the APIDs previously assigned is not bound to the vfio_ap device
760 * driver; or, if no APIDs have yet been assigned, the APQI is not
761 * contained in an APQN bound to the vfio_ap device driver.
762 *
763 * 4. -EADDRINUSE
764 * An APQN derived from the cross product of the APQI being assigned
765 * and the APIDs previously assigned is being used by another mediated
766 * matrix device
767 */
assign_domain_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)768 static ssize_t assign_domain_store(struct device *dev,
769 struct device_attribute *attr,
770 const char *buf, size_t count)
771 {
772 int ret;
773 unsigned long apqi;
774 struct ap_matrix_mdev *matrix_mdev = dev_get_drvdata(dev);
775 unsigned long max_apqi = matrix_mdev->matrix.aqm_max;
776
777 mutex_lock(&matrix_dev->lock);
778
779 /* If the KVM guest is running, disallow assignment of domain */
780 if (matrix_mdev->kvm) {
781 ret = -EBUSY;
782 goto done;
783 }
784
785 ret = kstrtoul(buf, 0, &apqi);
786 if (ret)
787 goto done;
788 if (apqi > max_apqi) {
789 ret = -ENODEV;
790 goto done;
791 }
792
793 ret = vfio_ap_mdev_verify_queues_reserved_for_apqi(matrix_mdev, apqi);
794 if (ret)
795 goto done;
796
797 set_bit_inv(apqi, matrix_mdev->matrix.aqm);
798
799 ret = vfio_ap_mdev_verify_no_sharing(matrix_mdev);
800 if (ret)
801 goto share_err;
802
803 ret = count;
804 goto done;
805
806 share_err:
807 clear_bit_inv(apqi, matrix_mdev->matrix.aqm);
808 done:
809 mutex_unlock(&matrix_dev->lock);
810
811 return ret;
812 }
813 static DEVICE_ATTR_WO(assign_domain);
814
815
816 /**
817 * unassign_domain_store - parses the APQI from @buf and clears the
818 * corresponding bit in the mediated matrix device's AQM
819 *
820 * @dev: the matrix device
821 * @attr: the mediated matrix device's unassign_domain attribute
822 * @buf: a buffer containing the AP queue index (APQI) of the domain to
823 * be unassigned
824 * @count: the number of bytes in @buf
825 *
826 * Return: the number of bytes processed if the APQI is valid; otherwise,
827 * returns one of the following errors:
828 * -EINVAL if the APQI is not a number
829 * -ENODEV if the APQI exceeds the maximum value configured for the system
830 */
unassign_domain_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)831 static ssize_t unassign_domain_store(struct device *dev,
832 struct device_attribute *attr,
833 const char *buf, size_t count)
834 {
835 int ret;
836 unsigned long apqi;
837 struct ap_matrix_mdev *matrix_mdev = dev_get_drvdata(dev);
838
839 mutex_lock(&matrix_dev->lock);
840
841 /* If the KVM guest is running, disallow unassignment of domain */
842 if (matrix_mdev->kvm) {
843 ret = -EBUSY;
844 goto done;
845 }
846
847 ret = kstrtoul(buf, 0, &apqi);
848 if (ret)
849 goto done;
850
851 if (apqi > matrix_mdev->matrix.aqm_max) {
852 ret = -ENODEV;
853 goto done;
854 }
855
856 clear_bit_inv((unsigned long)apqi, matrix_mdev->matrix.aqm);
857 ret = count;
858
859 done:
860 mutex_unlock(&matrix_dev->lock);
861 return ret;
862 }
863 static DEVICE_ATTR_WO(unassign_domain);
864
865 /**
866 * assign_control_domain_store - parses the domain ID from @buf and sets
867 * the corresponding bit in the mediated matrix device's ADM
868 *
869 *
870 * @dev: the matrix device
871 * @attr: the mediated matrix device's assign_control_domain attribute
872 * @buf: a buffer containing the domain ID to be assigned
873 * @count: the number of bytes in @buf
874 *
875 * Return: the number of bytes processed if the domain ID is valid; otherwise,
876 * returns one of the following errors:
877 * -EINVAL if the ID is not a number
878 * -ENODEV if the ID exceeds the maximum value configured for the system
879 */
assign_control_domain_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)880 static ssize_t assign_control_domain_store(struct device *dev,
881 struct device_attribute *attr,
882 const char *buf, size_t count)
883 {
884 int ret;
885 unsigned long id;
886 struct ap_matrix_mdev *matrix_mdev = dev_get_drvdata(dev);
887
888 mutex_lock(&matrix_dev->lock);
889
890 /* If the KVM guest is running, disallow assignment of control domain */
891 if (matrix_mdev->kvm) {
892 ret = -EBUSY;
893 goto done;
894 }
895
896 ret = kstrtoul(buf, 0, &id);
897 if (ret)
898 goto done;
899
900 if (id > matrix_mdev->matrix.adm_max) {
901 ret = -ENODEV;
902 goto done;
903 }
904
905 /* Set the bit in the ADM (bitmask) corresponding to the AP control
906 * domain number (id). The bits in the mask, from most significant to
907 * least significant, correspond to IDs 0 up to the one less than the
908 * number of control domains that can be assigned.
909 */
910 set_bit_inv(id, matrix_mdev->matrix.adm);
911 ret = count;
912 done:
913 mutex_unlock(&matrix_dev->lock);
914 return ret;
915 }
916 static DEVICE_ATTR_WO(assign_control_domain);
917
918 /**
919 * unassign_control_domain_store - parses the domain ID from @buf and
920 * clears the corresponding bit in the mediated matrix device's ADM
921 *
922 * @dev: the matrix device
923 * @attr: the mediated matrix device's unassign_control_domain attribute
924 * @buf: a buffer containing the domain ID to be unassigned
925 * @count: the number of bytes in @buf
926 *
927 * Return: the number of bytes processed if the domain ID is valid; otherwise,
928 * returns one of the following errors:
929 * -EINVAL if the ID is not a number
930 * -ENODEV if the ID exceeds the maximum value configured for the system
931 */
unassign_control_domain_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)932 static ssize_t unassign_control_domain_store(struct device *dev,
933 struct device_attribute *attr,
934 const char *buf, size_t count)
935 {
936 int ret;
937 unsigned long domid;
938 struct ap_matrix_mdev *matrix_mdev = dev_get_drvdata(dev);
939 unsigned long max_domid = matrix_mdev->matrix.adm_max;
940
941 mutex_lock(&matrix_dev->lock);
942
943 /* If a KVM guest is running, disallow unassignment of control domain */
944 if (matrix_mdev->kvm) {
945 ret = -EBUSY;
946 goto done;
947 }
948
949 ret = kstrtoul(buf, 0, &domid);
950 if (ret)
951 goto done;
952 if (domid > max_domid) {
953 ret = -ENODEV;
954 goto done;
955 }
956
957 clear_bit_inv(domid, matrix_mdev->matrix.adm);
958 ret = count;
959 done:
960 mutex_unlock(&matrix_dev->lock);
961 return ret;
962 }
963 static DEVICE_ATTR_WO(unassign_control_domain);
964
control_domains_show(struct device * dev,struct device_attribute * dev_attr,char * buf)965 static ssize_t control_domains_show(struct device *dev,
966 struct device_attribute *dev_attr,
967 char *buf)
968 {
969 unsigned long id;
970 int nchars = 0;
971 int n;
972 char *bufpos = buf;
973 struct ap_matrix_mdev *matrix_mdev = dev_get_drvdata(dev);
974 unsigned long max_domid = matrix_mdev->matrix.adm_max;
975
976 mutex_lock(&matrix_dev->lock);
977 for_each_set_bit_inv(id, matrix_mdev->matrix.adm, max_domid + 1) {
978 n = sprintf(bufpos, "%04lx\n", id);
979 bufpos += n;
980 nchars += n;
981 }
982 mutex_unlock(&matrix_dev->lock);
983
984 return nchars;
985 }
986 static DEVICE_ATTR_RO(control_domains);
987
matrix_show(struct device * dev,struct device_attribute * attr,char * buf)988 static ssize_t matrix_show(struct device *dev, struct device_attribute *attr,
989 char *buf)
990 {
991 struct ap_matrix_mdev *matrix_mdev = dev_get_drvdata(dev);
992 char *bufpos = buf;
993 unsigned long apid;
994 unsigned long apqi;
995 unsigned long apid1;
996 unsigned long apqi1;
997 unsigned long napm_bits = matrix_mdev->matrix.apm_max + 1;
998 unsigned long naqm_bits = matrix_mdev->matrix.aqm_max + 1;
999 int nchars = 0;
1000 int n;
1001
1002 apid1 = find_first_bit_inv(matrix_mdev->matrix.apm, napm_bits);
1003 apqi1 = find_first_bit_inv(matrix_mdev->matrix.aqm, naqm_bits);
1004
1005 mutex_lock(&matrix_dev->lock);
1006
1007 if ((apid1 < napm_bits) && (apqi1 < naqm_bits)) {
1008 for_each_set_bit_inv(apid, matrix_mdev->matrix.apm, napm_bits) {
1009 for_each_set_bit_inv(apqi, matrix_mdev->matrix.aqm,
1010 naqm_bits) {
1011 n = sprintf(bufpos, "%02lx.%04lx\n", apid,
1012 apqi);
1013 bufpos += n;
1014 nchars += n;
1015 }
1016 }
1017 } else if (apid1 < napm_bits) {
1018 for_each_set_bit_inv(apid, matrix_mdev->matrix.apm, napm_bits) {
1019 n = sprintf(bufpos, "%02lx.\n", apid);
1020 bufpos += n;
1021 nchars += n;
1022 }
1023 } else if (apqi1 < naqm_bits) {
1024 for_each_set_bit_inv(apqi, matrix_mdev->matrix.aqm, naqm_bits) {
1025 n = sprintf(bufpos, ".%04lx\n", apqi);
1026 bufpos += n;
1027 nchars += n;
1028 }
1029 }
1030
1031 mutex_unlock(&matrix_dev->lock);
1032
1033 return nchars;
1034 }
1035 static DEVICE_ATTR_RO(matrix);
1036
1037 static struct attribute *vfio_ap_mdev_attrs[] = {
1038 &dev_attr_assign_adapter.attr,
1039 &dev_attr_unassign_adapter.attr,
1040 &dev_attr_assign_domain.attr,
1041 &dev_attr_unassign_domain.attr,
1042 &dev_attr_assign_control_domain.attr,
1043 &dev_attr_unassign_control_domain.attr,
1044 &dev_attr_control_domains.attr,
1045 &dev_attr_matrix.attr,
1046 NULL,
1047 };
1048
1049 static struct attribute_group vfio_ap_mdev_attr_group = {
1050 .attrs = vfio_ap_mdev_attrs
1051 };
1052
1053 static const struct attribute_group *vfio_ap_mdev_attr_groups[] = {
1054 &vfio_ap_mdev_attr_group,
1055 NULL
1056 };
1057
1058 /**
1059 * vfio_ap_mdev_set_kvm - sets all data for @matrix_mdev that are needed
1060 * to manage AP resources for the guest whose state is represented by @kvm
1061 *
1062 * @matrix_mdev: a mediated matrix device
1063 * @kvm: reference to KVM instance
1064 *
1065 * Note: The matrix_dev->lock must be taken prior to calling
1066 * this function; however, the lock will be temporarily released while the
1067 * guest's AP configuration is set to avoid a potential lockdep splat.
1068 * The kvm->lock is taken to set the guest's AP configuration which, under
1069 * certain circumstances, will result in a circular lock dependency if this is
1070 * done under the @matrix_mdev->lock.
1071 *
1072 * Return: 0 if no other mediated matrix device has a reference to @kvm;
1073 * otherwise, returns an -EPERM.
1074 */
vfio_ap_mdev_set_kvm(struct ap_matrix_mdev * matrix_mdev,struct kvm * kvm)1075 static int vfio_ap_mdev_set_kvm(struct ap_matrix_mdev *matrix_mdev,
1076 struct kvm *kvm)
1077 {
1078 struct ap_matrix_mdev *m;
1079
1080 if (kvm->arch.crypto.crycbd) {
1081 down_write(&kvm->arch.crypto.pqap_hook_rwsem);
1082 kvm->arch.crypto.pqap_hook = &matrix_mdev->pqap_hook;
1083 up_write(&kvm->arch.crypto.pqap_hook_rwsem);
1084
1085 mutex_lock(&kvm->lock);
1086 mutex_lock(&matrix_dev->lock);
1087
1088 list_for_each_entry(m, &matrix_dev->mdev_list, node) {
1089 if (m != matrix_mdev && m->kvm == kvm) {
1090 mutex_unlock(&kvm->lock);
1091 mutex_unlock(&matrix_dev->lock);
1092 return -EPERM;
1093 }
1094 }
1095
1096 kvm_get_kvm(kvm);
1097 matrix_mdev->kvm = kvm;
1098 kvm_arch_crypto_set_masks(kvm,
1099 matrix_mdev->matrix.apm,
1100 matrix_mdev->matrix.aqm,
1101 matrix_mdev->matrix.adm);
1102
1103 mutex_unlock(&kvm->lock);
1104 mutex_unlock(&matrix_dev->lock);
1105 }
1106
1107 return 0;
1108 }
1109
1110 /**
1111 * vfio_ap_mdev_iommu_notifier - IOMMU notifier callback
1112 *
1113 * @nb: The notifier block
1114 * @action: Action to be taken
1115 * @data: data associated with the request
1116 *
1117 * For an UNMAP request, unpin the guest IOVA (the NIB guest address we
1118 * pinned before). Other requests are ignored.
1119 *
1120 * Return: for an UNMAP request, NOFITY_OK; otherwise NOTIFY_DONE.
1121 */
vfio_ap_mdev_iommu_notifier(struct notifier_block * nb,unsigned long action,void * data)1122 static int vfio_ap_mdev_iommu_notifier(struct notifier_block *nb,
1123 unsigned long action, void *data)
1124 {
1125 struct ap_matrix_mdev *matrix_mdev;
1126
1127 matrix_mdev = container_of(nb, struct ap_matrix_mdev, iommu_notifier);
1128
1129 if (action == VFIO_IOMMU_NOTIFY_DMA_UNMAP) {
1130 struct vfio_iommu_type1_dma_unmap *unmap = data;
1131 unsigned long g_pfn = unmap->iova >> PAGE_SHIFT;
1132
1133 vfio_unpin_pages(mdev_dev(matrix_mdev->mdev), &g_pfn, 1);
1134 return NOTIFY_OK;
1135 }
1136
1137 return NOTIFY_DONE;
1138 }
1139
1140 /**
1141 * vfio_ap_mdev_unset_kvm - performs clean-up of resources no longer needed
1142 * by @matrix_mdev.
1143 *
1144 * @matrix_mdev: a matrix mediated device
1145 *
1146 * Note: The matrix_dev->lock must be taken prior to calling
1147 * this function; however, the lock will be temporarily released while the
1148 * guest's AP configuration is cleared to avoid a potential lockdep splat.
1149 * The kvm->lock is taken to clear the guest's AP configuration which, under
1150 * certain circumstances, will result in a circular lock dependency if this is
1151 * done under the @matrix_mdev->lock.
1152 */
vfio_ap_mdev_unset_kvm(struct ap_matrix_mdev * matrix_mdev,struct kvm * kvm)1153 static void vfio_ap_mdev_unset_kvm(struct ap_matrix_mdev *matrix_mdev,
1154 struct kvm *kvm)
1155 {
1156 if (kvm && kvm->arch.crypto.crycbd) {
1157 down_write(&kvm->arch.crypto.pqap_hook_rwsem);
1158 kvm->arch.crypto.pqap_hook = NULL;
1159 up_write(&kvm->arch.crypto.pqap_hook_rwsem);
1160
1161 mutex_lock(&kvm->lock);
1162 mutex_lock(&matrix_dev->lock);
1163
1164 kvm_arch_crypto_clear_masks(kvm);
1165 vfio_ap_mdev_reset_queues(matrix_mdev);
1166 kvm_put_kvm(kvm);
1167 matrix_mdev->kvm = NULL;
1168
1169 mutex_unlock(&kvm->lock);
1170 mutex_unlock(&matrix_dev->lock);
1171 }
1172 }
1173
vfio_ap_mdev_group_notifier(struct notifier_block * nb,unsigned long action,void * data)1174 static int vfio_ap_mdev_group_notifier(struct notifier_block *nb,
1175 unsigned long action, void *data)
1176 {
1177 int notify_rc = NOTIFY_OK;
1178 struct ap_matrix_mdev *matrix_mdev;
1179
1180 if (action != VFIO_GROUP_NOTIFY_SET_KVM)
1181 return NOTIFY_OK;
1182
1183 matrix_mdev = container_of(nb, struct ap_matrix_mdev, group_notifier);
1184
1185 if (!data)
1186 vfio_ap_mdev_unset_kvm(matrix_mdev, matrix_mdev->kvm);
1187 else if (vfio_ap_mdev_set_kvm(matrix_mdev, data))
1188 notify_rc = NOTIFY_DONE;
1189
1190 return notify_rc;
1191 }
1192
vfio_ap_find_queue(int apqn)1193 static struct vfio_ap_queue *vfio_ap_find_queue(int apqn)
1194 {
1195 struct device *dev;
1196 struct vfio_ap_queue *q = NULL;
1197
1198 dev = driver_find_device(&matrix_dev->vfio_ap_drv->driver, NULL,
1199 &apqn, match_apqn);
1200 if (dev) {
1201 q = dev_get_drvdata(dev);
1202 put_device(dev);
1203 }
1204
1205 return q;
1206 }
1207
vfio_ap_mdev_reset_queue(struct vfio_ap_queue * q,unsigned int retry)1208 int vfio_ap_mdev_reset_queue(struct vfio_ap_queue *q,
1209 unsigned int retry)
1210 {
1211 struct ap_queue_status status;
1212 int ret;
1213 int retry2 = 2;
1214
1215 if (!q)
1216 return 0;
1217
1218 retry_zapq:
1219 status = ap_zapq(q->apqn);
1220 switch (status.response_code) {
1221 case AP_RESPONSE_NORMAL:
1222 ret = 0;
1223 break;
1224 case AP_RESPONSE_RESET_IN_PROGRESS:
1225 if (retry--) {
1226 msleep(20);
1227 goto retry_zapq;
1228 }
1229 ret = -EBUSY;
1230 break;
1231 case AP_RESPONSE_Q_NOT_AVAIL:
1232 case AP_RESPONSE_DECONFIGURED:
1233 case AP_RESPONSE_CHECKSTOPPED:
1234 WARN_ON_ONCE(status.irq_enabled);
1235 ret = -EBUSY;
1236 goto free_resources;
1237 default:
1238 /* things are really broken, give up */
1239 WARN(true, "PQAP/ZAPQ completed with invalid rc (%x)\n",
1240 status.response_code);
1241 return -EIO;
1242 }
1243
1244 /* wait for the reset to take effect */
1245 while (retry2--) {
1246 if (status.queue_empty && !status.irq_enabled)
1247 break;
1248 msleep(20);
1249 status = ap_tapq(q->apqn, NULL);
1250 }
1251 WARN_ON_ONCE(retry2 <= 0);
1252
1253 free_resources:
1254 vfio_ap_free_aqic_resources(q);
1255
1256 return ret;
1257 }
1258
vfio_ap_mdev_reset_queues(struct ap_matrix_mdev * matrix_mdev)1259 static int vfio_ap_mdev_reset_queues(struct ap_matrix_mdev *matrix_mdev)
1260 {
1261 int ret;
1262 int rc = 0;
1263 unsigned long apid, apqi;
1264 struct vfio_ap_queue *q;
1265
1266 for_each_set_bit_inv(apid, matrix_mdev->matrix.apm,
1267 matrix_mdev->matrix.apm_max + 1) {
1268 for_each_set_bit_inv(apqi, matrix_mdev->matrix.aqm,
1269 matrix_mdev->matrix.aqm_max + 1) {
1270 q = vfio_ap_find_queue(AP_MKQID(apid, apqi));
1271 ret = vfio_ap_mdev_reset_queue(q, 1);
1272 /*
1273 * Regardless whether a queue turns out to be busy, or
1274 * is not operational, we need to continue resetting
1275 * the remaining queues.
1276 */
1277 if (ret)
1278 rc = ret;
1279 }
1280 }
1281
1282 return rc;
1283 }
1284
vfio_ap_mdev_open_device(struct vfio_device * vdev)1285 static int vfio_ap_mdev_open_device(struct vfio_device *vdev)
1286 {
1287 struct ap_matrix_mdev *matrix_mdev =
1288 container_of(vdev, struct ap_matrix_mdev, vdev);
1289 unsigned long events;
1290 int ret;
1291
1292 matrix_mdev->group_notifier.notifier_call = vfio_ap_mdev_group_notifier;
1293 events = VFIO_GROUP_NOTIFY_SET_KVM;
1294
1295 ret = vfio_register_notifier(vdev->dev, VFIO_GROUP_NOTIFY,
1296 &events, &matrix_mdev->group_notifier);
1297 if (ret)
1298 return ret;
1299
1300 matrix_mdev->iommu_notifier.notifier_call = vfio_ap_mdev_iommu_notifier;
1301 events = VFIO_IOMMU_NOTIFY_DMA_UNMAP;
1302 ret = vfio_register_notifier(vdev->dev, VFIO_IOMMU_NOTIFY,
1303 &events, &matrix_mdev->iommu_notifier);
1304 if (ret)
1305 goto out_unregister_group;
1306 return 0;
1307
1308 out_unregister_group:
1309 vfio_unregister_notifier(vdev->dev, VFIO_GROUP_NOTIFY,
1310 &matrix_mdev->group_notifier);
1311 return ret;
1312 }
1313
vfio_ap_mdev_close_device(struct vfio_device * vdev)1314 static void vfio_ap_mdev_close_device(struct vfio_device *vdev)
1315 {
1316 struct ap_matrix_mdev *matrix_mdev =
1317 container_of(vdev, struct ap_matrix_mdev, vdev);
1318
1319 vfio_unregister_notifier(vdev->dev, VFIO_IOMMU_NOTIFY,
1320 &matrix_mdev->iommu_notifier);
1321 vfio_unregister_notifier(vdev->dev, VFIO_GROUP_NOTIFY,
1322 &matrix_mdev->group_notifier);
1323 vfio_ap_mdev_unset_kvm(matrix_mdev, matrix_mdev->kvm);
1324 }
1325
vfio_ap_mdev_get_device_info(unsigned long arg)1326 static int vfio_ap_mdev_get_device_info(unsigned long arg)
1327 {
1328 unsigned long minsz;
1329 struct vfio_device_info info;
1330
1331 minsz = offsetofend(struct vfio_device_info, num_irqs);
1332
1333 if (copy_from_user(&info, (void __user *)arg, minsz))
1334 return -EFAULT;
1335
1336 if (info.argsz < minsz)
1337 return -EINVAL;
1338
1339 info.flags = VFIO_DEVICE_FLAGS_AP | VFIO_DEVICE_FLAGS_RESET;
1340 info.num_regions = 0;
1341 info.num_irqs = 0;
1342
1343 return copy_to_user((void __user *)arg, &info, minsz) ? -EFAULT : 0;
1344 }
1345
vfio_ap_mdev_ioctl(struct vfio_device * vdev,unsigned int cmd,unsigned long arg)1346 static ssize_t vfio_ap_mdev_ioctl(struct vfio_device *vdev,
1347 unsigned int cmd, unsigned long arg)
1348 {
1349 struct ap_matrix_mdev *matrix_mdev =
1350 container_of(vdev, struct ap_matrix_mdev, vdev);
1351 int ret;
1352
1353 mutex_lock(&matrix_dev->lock);
1354 switch (cmd) {
1355 case VFIO_DEVICE_GET_INFO:
1356 ret = vfio_ap_mdev_get_device_info(arg);
1357 break;
1358 case VFIO_DEVICE_RESET:
1359 ret = vfio_ap_mdev_reset_queues(matrix_mdev);
1360 break;
1361 default:
1362 ret = -EOPNOTSUPP;
1363 break;
1364 }
1365 mutex_unlock(&matrix_dev->lock);
1366
1367 return ret;
1368 }
1369
1370 static const struct vfio_device_ops vfio_ap_matrix_dev_ops = {
1371 .open_device = vfio_ap_mdev_open_device,
1372 .close_device = vfio_ap_mdev_close_device,
1373 .ioctl = vfio_ap_mdev_ioctl,
1374 };
1375
1376 static struct mdev_driver vfio_ap_matrix_driver = {
1377 .driver = {
1378 .name = "vfio_ap_mdev",
1379 .owner = THIS_MODULE,
1380 .mod_name = KBUILD_MODNAME,
1381 .dev_groups = vfio_ap_mdev_attr_groups,
1382 },
1383 .probe = vfio_ap_mdev_probe,
1384 .remove = vfio_ap_mdev_remove,
1385 };
1386
1387 static const struct mdev_parent_ops vfio_ap_matrix_ops = {
1388 .owner = THIS_MODULE,
1389 .device_driver = &vfio_ap_matrix_driver,
1390 .supported_type_groups = vfio_ap_mdev_type_groups,
1391 };
1392
vfio_ap_mdev_register(void)1393 int vfio_ap_mdev_register(void)
1394 {
1395 int ret;
1396
1397 atomic_set(&matrix_dev->available_instances, MAX_ZDEV_ENTRIES_EXT);
1398
1399 ret = mdev_register_driver(&vfio_ap_matrix_driver);
1400 if (ret)
1401 return ret;
1402
1403 ret = mdev_register_device(&matrix_dev->device, &vfio_ap_matrix_ops);
1404 if (ret)
1405 goto err_driver;
1406 return 0;
1407
1408 err_driver:
1409 mdev_unregister_driver(&vfio_ap_matrix_driver);
1410 return ret;
1411 }
1412
vfio_ap_mdev_unregister(void)1413 void vfio_ap_mdev_unregister(void)
1414 {
1415 mdev_unregister_device(&matrix_dev->device);
1416 mdev_unregister_driver(&vfio_ap_matrix_driver);
1417 }
1418
