1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (C) 2013 - Virtual Open Systems
4 * Author: Antonios Motakis <a.motakis@virtualopensystems.com>
5 */
6
7 #define dev_fmt(fmt) "VFIO: " fmt
8
9 #include <linux/device.h>
10 #include <linux/acpi.h>
11 #include <linux/iommu.h>
12 #include <linux/module.h>
13 #include <linux/mutex.h>
14 #include <linux/pm_runtime.h>
15 #include <linux/slab.h>
16 #include <linux/types.h>
17 #include <linux/uaccess.h>
18 #include <linux/vfio.h>
19
20 #include "vfio_platform_private.h"
21
22 #define DRIVER_VERSION "0.10"
23 #define DRIVER_AUTHOR "Antonios Motakis <a.motakis@virtualopensystems.com>"
24 #define DRIVER_DESC "VFIO platform base module"
25
26 #define VFIO_PLATFORM_IS_ACPI(vdev) ((vdev)->acpihid != NULL)
27
28 static LIST_HEAD(reset_list);
29 static DEFINE_MUTEX(driver_lock);
30
vfio_platform_lookup_reset(const char * compat,struct module ** module)31 static vfio_platform_reset_fn_t vfio_platform_lookup_reset(const char *compat,
32 struct module **module)
33 {
34 struct vfio_platform_reset_node *iter;
35 vfio_platform_reset_fn_t reset_fn = NULL;
36
37 mutex_lock(&driver_lock);
38 list_for_each_entry(iter, &reset_list, link) {
39 if (!strcmp(iter->compat, compat) &&
40 try_module_get(iter->owner)) {
41 *module = iter->owner;
42 reset_fn = iter->of_reset;
43 break;
44 }
45 }
46 mutex_unlock(&driver_lock);
47 return reset_fn;
48 }
49
vfio_platform_acpi_probe(struct vfio_platform_device * vdev,struct device * dev)50 static int vfio_platform_acpi_probe(struct vfio_platform_device *vdev,
51 struct device *dev)
52 {
53 struct acpi_device *adev;
54
55 if (acpi_disabled)
56 return -ENOENT;
57
58 adev = ACPI_COMPANION(dev);
59 if (!adev) {
60 dev_err(dev, "ACPI companion device not found for %s\n",
61 vdev->name);
62 return -ENODEV;
63 }
64
65 #ifdef CONFIG_ACPI
66 vdev->acpihid = acpi_device_hid(adev);
67 #endif
68 return WARN_ON(!vdev->acpihid) ? -EINVAL : 0;
69 }
70
vfio_platform_acpi_call_reset(struct vfio_platform_device * vdev,const char ** extra_dbg)71 static int vfio_platform_acpi_call_reset(struct vfio_platform_device *vdev,
72 const char **extra_dbg)
73 {
74 #ifdef CONFIG_ACPI
75 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
76 struct device *dev = vdev->device;
77 acpi_handle handle = ACPI_HANDLE(dev);
78 acpi_status acpi_ret;
79
80 acpi_ret = acpi_evaluate_object(handle, "_RST", NULL, &buffer);
81 if (ACPI_FAILURE(acpi_ret)) {
82 if (extra_dbg)
83 *extra_dbg = acpi_format_exception(acpi_ret);
84 return -EINVAL;
85 }
86
87 return 0;
88 #else
89 return -ENOENT;
90 #endif
91 }
92
vfio_platform_acpi_has_reset(struct vfio_platform_device * vdev)93 static bool vfio_platform_acpi_has_reset(struct vfio_platform_device *vdev)
94 {
95 #ifdef CONFIG_ACPI
96 struct device *dev = vdev->device;
97 acpi_handle handle = ACPI_HANDLE(dev);
98
99 return acpi_has_method(handle, "_RST");
100 #else
101 return false;
102 #endif
103 }
104
vfio_platform_has_reset(struct vfio_platform_device * vdev)105 static bool vfio_platform_has_reset(struct vfio_platform_device *vdev)
106 {
107 if (VFIO_PLATFORM_IS_ACPI(vdev))
108 return vfio_platform_acpi_has_reset(vdev);
109
110 return vdev->of_reset ? true : false;
111 }
112
vfio_platform_get_reset(struct vfio_platform_device * vdev)113 static int vfio_platform_get_reset(struct vfio_platform_device *vdev)
114 {
115 if (VFIO_PLATFORM_IS_ACPI(vdev))
116 return vfio_platform_acpi_has_reset(vdev) ? 0 : -ENOENT;
117
118 vdev->of_reset = vfio_platform_lookup_reset(vdev->compat,
119 &vdev->reset_module);
120 if (!vdev->of_reset) {
121 request_module("vfio-reset:%s", vdev->compat);
122 vdev->of_reset = vfio_platform_lookup_reset(vdev->compat,
123 &vdev->reset_module);
124 }
125
126 return vdev->of_reset ? 0 : -ENOENT;
127 }
128
vfio_platform_put_reset(struct vfio_platform_device * vdev)129 static void vfio_platform_put_reset(struct vfio_platform_device *vdev)
130 {
131 if (VFIO_PLATFORM_IS_ACPI(vdev))
132 return;
133
134 if (vdev->of_reset)
135 module_put(vdev->reset_module);
136 }
137
vfio_platform_regions_init(struct vfio_platform_device * vdev)138 static int vfio_platform_regions_init(struct vfio_platform_device *vdev)
139 {
140 int cnt = 0, i;
141
142 while (vdev->get_resource(vdev, cnt))
143 cnt++;
144
145 vdev->regions = kcalloc(cnt, sizeof(struct vfio_platform_region),
146 GFP_KERNEL);
147 if (!vdev->regions)
148 return -ENOMEM;
149
150 for (i = 0; i < cnt; i++) {
151 struct resource *res =
152 vdev->get_resource(vdev, i);
153
154 if (!res)
155 goto err;
156
157 vdev->regions[i].addr = res->start;
158 vdev->regions[i].size = resource_size(res);
159 vdev->regions[i].flags = 0;
160
161 switch (resource_type(res)) {
162 case IORESOURCE_MEM:
163 vdev->regions[i].type = VFIO_PLATFORM_REGION_TYPE_MMIO;
164 vdev->regions[i].flags |= VFIO_REGION_INFO_FLAG_READ;
165 if (!(res->flags & IORESOURCE_READONLY))
166 vdev->regions[i].flags |=
167 VFIO_REGION_INFO_FLAG_WRITE;
168
169 /*
170 * Only regions addressed with PAGE granularity may be
171 * MMAPed securely.
172 */
173 if (!(vdev->regions[i].addr & ~PAGE_MASK) &&
174 !(vdev->regions[i].size & ~PAGE_MASK))
175 vdev->regions[i].flags |=
176 VFIO_REGION_INFO_FLAG_MMAP;
177
178 break;
179 case IORESOURCE_IO:
180 vdev->regions[i].type = VFIO_PLATFORM_REGION_TYPE_PIO;
181 break;
182 default:
183 goto err;
184 }
185 }
186
187 vdev->num_regions = cnt;
188
189 return 0;
190 err:
191 kfree(vdev->regions);
192 return -EINVAL;
193 }
194
vfio_platform_regions_cleanup(struct vfio_platform_device * vdev)195 static void vfio_platform_regions_cleanup(struct vfio_platform_device *vdev)
196 {
197 int i;
198
199 for (i = 0; i < vdev->num_regions; i++)
200 iounmap(vdev->regions[i].ioaddr);
201
202 vdev->num_regions = 0;
203 kfree(vdev->regions);
204 }
205
vfio_platform_call_reset(struct vfio_platform_device * vdev,const char ** extra_dbg)206 static int vfio_platform_call_reset(struct vfio_platform_device *vdev,
207 const char **extra_dbg)
208 {
209 if (VFIO_PLATFORM_IS_ACPI(vdev)) {
210 dev_info(vdev->device, "reset\n");
211 return vfio_platform_acpi_call_reset(vdev, extra_dbg);
212 } else if (vdev->of_reset) {
213 dev_info(vdev->device, "reset\n");
214 return vdev->of_reset(vdev);
215 }
216
217 dev_warn(vdev->device, "no reset function found!\n");
218 return -EINVAL;
219 }
220
vfio_platform_close_device(struct vfio_device * core_vdev)221 void vfio_platform_close_device(struct vfio_device *core_vdev)
222 {
223 struct vfio_platform_device *vdev =
224 container_of(core_vdev, struct vfio_platform_device, vdev);
225 const char *extra_dbg = NULL;
226 int ret;
227
228 ret = vfio_platform_call_reset(vdev, &extra_dbg);
229 if (WARN_ON(ret && vdev->reset_required)) {
230 dev_warn(
231 vdev->device,
232 "reset driver is required and reset call failed in release (%d) %s\n",
233 ret, extra_dbg ? extra_dbg : "");
234 }
235 pm_runtime_put(vdev->device);
236 vfio_platform_regions_cleanup(vdev);
237 vfio_platform_irq_cleanup(vdev);
238 }
239 EXPORT_SYMBOL_GPL(vfio_platform_close_device);
240
vfio_platform_open_device(struct vfio_device * core_vdev)241 int vfio_platform_open_device(struct vfio_device *core_vdev)
242 {
243 struct vfio_platform_device *vdev =
244 container_of(core_vdev, struct vfio_platform_device, vdev);
245 const char *extra_dbg = NULL;
246 int ret;
247
248 ret = vfio_platform_regions_init(vdev);
249 if (ret)
250 return ret;
251
252 ret = vfio_platform_irq_init(vdev);
253 if (ret)
254 goto err_irq;
255
256 ret = pm_runtime_get_sync(vdev->device);
257 if (ret < 0)
258 goto err_rst;
259
260 ret = vfio_platform_call_reset(vdev, &extra_dbg);
261 if (ret && vdev->reset_required) {
262 dev_warn(
263 vdev->device,
264 "reset driver is required and reset call failed in open (%d) %s\n",
265 ret, extra_dbg ? extra_dbg : "");
266 goto err_rst;
267 }
268 return 0;
269
270 err_rst:
271 pm_runtime_put(vdev->device);
272 vfio_platform_irq_cleanup(vdev);
273 err_irq:
274 vfio_platform_regions_cleanup(vdev);
275 return ret;
276 }
277 EXPORT_SYMBOL_GPL(vfio_platform_open_device);
278
vfio_platform_ioctl(struct vfio_device * core_vdev,unsigned int cmd,unsigned long arg)279 long vfio_platform_ioctl(struct vfio_device *core_vdev,
280 unsigned int cmd, unsigned long arg)
281 {
282 struct vfio_platform_device *vdev =
283 container_of(core_vdev, struct vfio_platform_device, vdev);
284
285 unsigned long minsz;
286
287 if (cmd == VFIO_DEVICE_GET_INFO) {
288 struct vfio_device_info info;
289
290 minsz = offsetofend(struct vfio_device_info, num_irqs);
291
292 if (copy_from_user(&info, (void __user *)arg, minsz))
293 return -EFAULT;
294
295 if (info.argsz < minsz)
296 return -EINVAL;
297
298 if (vfio_platform_has_reset(vdev))
299 vdev->flags |= VFIO_DEVICE_FLAGS_RESET;
300 info.flags = vdev->flags;
301 info.num_regions = vdev->num_regions;
302 info.num_irqs = vdev->num_irqs;
303
304 return copy_to_user((void __user *)arg, &info, minsz) ?
305 -EFAULT : 0;
306
307 } else if (cmd == VFIO_DEVICE_GET_REGION_INFO) {
308 struct vfio_region_info info;
309
310 minsz = offsetofend(struct vfio_region_info, offset);
311
312 if (copy_from_user(&info, (void __user *)arg, minsz))
313 return -EFAULT;
314
315 if (info.argsz < minsz)
316 return -EINVAL;
317
318 if (info.index >= vdev->num_regions)
319 return -EINVAL;
320
321 /* map offset to the physical address */
322 info.offset = VFIO_PLATFORM_INDEX_TO_OFFSET(info.index);
323 info.size = vdev->regions[info.index].size;
324 info.flags = vdev->regions[info.index].flags;
325
326 return copy_to_user((void __user *)arg, &info, minsz) ?
327 -EFAULT : 0;
328
329 } else if (cmd == VFIO_DEVICE_GET_IRQ_INFO) {
330 struct vfio_irq_info info;
331
332 minsz = offsetofend(struct vfio_irq_info, count);
333
334 if (copy_from_user(&info, (void __user *)arg, minsz))
335 return -EFAULT;
336
337 if (info.argsz < minsz)
338 return -EINVAL;
339
340 if (info.index >= vdev->num_irqs)
341 return -EINVAL;
342
343 info.flags = vdev->irqs[info.index].flags;
344 info.count = vdev->irqs[info.index].count;
345
346 return copy_to_user((void __user *)arg, &info, minsz) ?
347 -EFAULT : 0;
348
349 } else if (cmd == VFIO_DEVICE_SET_IRQS) {
350 struct vfio_irq_set hdr;
351 u8 *data = NULL;
352 int ret = 0;
353 size_t data_size = 0;
354
355 minsz = offsetofend(struct vfio_irq_set, count);
356
357 if (copy_from_user(&hdr, (void __user *)arg, minsz))
358 return -EFAULT;
359
360 ret = vfio_set_irqs_validate_and_prepare(&hdr, vdev->num_irqs,
361 vdev->num_irqs, &data_size);
362 if (ret)
363 return ret;
364
365 if (data_size) {
366 data = memdup_user((void __user *)(arg + minsz),
367 data_size);
368 if (IS_ERR(data))
369 return PTR_ERR(data);
370 }
371
372 mutex_lock(&vdev->igate);
373
374 ret = vfio_platform_set_irqs_ioctl(vdev, hdr.flags, hdr.index,
375 hdr.start, hdr.count, data);
376 mutex_unlock(&vdev->igate);
377 kfree(data);
378
379 return ret;
380
381 } else if (cmd == VFIO_DEVICE_RESET) {
382 return vfio_platform_call_reset(vdev, NULL);
383 }
384
385 return -ENOTTY;
386 }
387 EXPORT_SYMBOL_GPL(vfio_platform_ioctl);
388
vfio_platform_read_mmio(struct vfio_platform_region * reg,char __user * buf,size_t count,loff_t off)389 static ssize_t vfio_platform_read_mmio(struct vfio_platform_region *reg,
390 char __user *buf, size_t count,
391 loff_t off)
392 {
393 unsigned int done = 0;
394
395 if (!reg->ioaddr) {
396 reg->ioaddr =
397 ioremap(reg->addr, reg->size);
398
399 if (!reg->ioaddr)
400 return -ENOMEM;
401 }
402
403 while (count) {
404 size_t filled;
405
406 if (count >= 4 && !(off % 4)) {
407 u32 val;
408
409 val = ioread32(reg->ioaddr + off);
410 if (copy_to_user(buf, &val, 4))
411 goto err;
412
413 filled = 4;
414 } else if (count >= 2 && !(off % 2)) {
415 u16 val;
416
417 val = ioread16(reg->ioaddr + off);
418 if (copy_to_user(buf, &val, 2))
419 goto err;
420
421 filled = 2;
422 } else {
423 u8 val;
424
425 val = ioread8(reg->ioaddr + off);
426 if (copy_to_user(buf, &val, 1))
427 goto err;
428
429 filled = 1;
430 }
431
432
433 count -= filled;
434 done += filled;
435 off += filled;
436 buf += filled;
437 }
438
439 return done;
440 err:
441 return -EFAULT;
442 }
443
vfio_platform_read(struct vfio_device * core_vdev,char __user * buf,size_t count,loff_t * ppos)444 ssize_t vfio_platform_read(struct vfio_device *core_vdev,
445 char __user *buf, size_t count, loff_t *ppos)
446 {
447 struct vfio_platform_device *vdev =
448 container_of(core_vdev, struct vfio_platform_device, vdev);
449 unsigned int index = VFIO_PLATFORM_OFFSET_TO_INDEX(*ppos);
450 loff_t off = *ppos & VFIO_PLATFORM_OFFSET_MASK;
451
452 if (index >= vdev->num_regions)
453 return -EINVAL;
454
455 if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_READ))
456 return -EINVAL;
457
458 if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_MMIO)
459 return vfio_platform_read_mmio(&vdev->regions[index],
460 buf, count, off);
461 else if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_PIO)
462 return -EINVAL; /* not implemented */
463
464 return -EINVAL;
465 }
466 EXPORT_SYMBOL_GPL(vfio_platform_read);
467
vfio_platform_write_mmio(struct vfio_platform_region * reg,const char __user * buf,size_t count,loff_t off)468 static ssize_t vfio_platform_write_mmio(struct vfio_platform_region *reg,
469 const char __user *buf, size_t count,
470 loff_t off)
471 {
472 unsigned int done = 0;
473
474 if (!reg->ioaddr) {
475 reg->ioaddr =
476 ioremap(reg->addr, reg->size);
477
478 if (!reg->ioaddr)
479 return -ENOMEM;
480 }
481
482 while (count) {
483 size_t filled;
484
485 if (count >= 4 && !(off % 4)) {
486 u32 val;
487
488 if (copy_from_user(&val, buf, 4))
489 goto err;
490 iowrite32(val, reg->ioaddr + off);
491
492 filled = 4;
493 } else if (count >= 2 && !(off % 2)) {
494 u16 val;
495
496 if (copy_from_user(&val, buf, 2))
497 goto err;
498 iowrite16(val, reg->ioaddr + off);
499
500 filled = 2;
501 } else {
502 u8 val;
503
504 if (copy_from_user(&val, buf, 1))
505 goto err;
506 iowrite8(val, reg->ioaddr + off);
507
508 filled = 1;
509 }
510
511 count -= filled;
512 done += filled;
513 off += filled;
514 buf += filled;
515 }
516
517 return done;
518 err:
519 return -EFAULT;
520 }
521
vfio_platform_write(struct vfio_device * core_vdev,const char __user * buf,size_t count,loff_t * ppos)522 ssize_t vfio_platform_write(struct vfio_device *core_vdev, const char __user *buf,
523 size_t count, loff_t *ppos)
524 {
525 struct vfio_platform_device *vdev =
526 container_of(core_vdev, struct vfio_platform_device, vdev);
527 unsigned int index = VFIO_PLATFORM_OFFSET_TO_INDEX(*ppos);
528 loff_t off = *ppos & VFIO_PLATFORM_OFFSET_MASK;
529
530 if (index >= vdev->num_regions)
531 return -EINVAL;
532
533 if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_WRITE))
534 return -EINVAL;
535
536 if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_MMIO)
537 return vfio_platform_write_mmio(&vdev->regions[index],
538 buf, count, off);
539 else if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_PIO)
540 return -EINVAL; /* not implemented */
541
542 return -EINVAL;
543 }
544 EXPORT_SYMBOL_GPL(vfio_platform_write);
545
vfio_platform_mmap_mmio(struct vfio_platform_region region,struct vm_area_struct * vma)546 static int vfio_platform_mmap_mmio(struct vfio_platform_region region,
547 struct vm_area_struct *vma)
548 {
549 u64 req_len, pgoff, req_start;
550
551 req_len = vma->vm_end - vma->vm_start;
552 pgoff = vma->vm_pgoff &
553 ((1U << (VFIO_PLATFORM_OFFSET_SHIFT - PAGE_SHIFT)) - 1);
554 req_start = pgoff << PAGE_SHIFT;
555
556 if (region.size < PAGE_SIZE || req_start + req_len > region.size)
557 return -EINVAL;
558
559 vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
560 vma->vm_pgoff = (region.addr >> PAGE_SHIFT) + pgoff;
561
562 return remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
563 req_len, vma->vm_page_prot);
564 }
565
vfio_platform_mmap(struct vfio_device * core_vdev,struct vm_area_struct * vma)566 int vfio_platform_mmap(struct vfio_device *core_vdev, struct vm_area_struct *vma)
567 {
568 struct vfio_platform_device *vdev =
569 container_of(core_vdev, struct vfio_platform_device, vdev);
570 unsigned int index;
571
572 index = vma->vm_pgoff >> (VFIO_PLATFORM_OFFSET_SHIFT - PAGE_SHIFT);
573
574 if (vma->vm_end < vma->vm_start)
575 return -EINVAL;
576 if (!(vma->vm_flags & VM_SHARED))
577 return -EINVAL;
578 if (index >= vdev->num_regions)
579 return -EINVAL;
580 if (vma->vm_start & ~PAGE_MASK)
581 return -EINVAL;
582 if (vma->vm_end & ~PAGE_MASK)
583 return -EINVAL;
584
585 if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_MMAP))
586 return -EINVAL;
587
588 if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_READ)
589 && (vma->vm_flags & VM_READ))
590 return -EINVAL;
591
592 if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_WRITE)
593 && (vma->vm_flags & VM_WRITE))
594 return -EINVAL;
595
596 vma->vm_private_data = vdev;
597
598 if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_MMIO)
599 return vfio_platform_mmap_mmio(vdev->regions[index], vma);
600
601 else if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_PIO)
602 return -EINVAL; /* not implemented */
603
604 return -EINVAL;
605 }
606 EXPORT_SYMBOL_GPL(vfio_platform_mmap);
607
vfio_platform_of_probe(struct vfio_platform_device * vdev,struct device * dev)608 static int vfio_platform_of_probe(struct vfio_platform_device *vdev,
609 struct device *dev)
610 {
611 int ret;
612
613 ret = device_property_read_string(dev, "compatible",
614 &vdev->compat);
615 if (ret)
616 dev_err(dev, "Cannot retrieve compat for %s\n", vdev->name);
617
618 return ret;
619 }
620
621 /*
622 * There can be two kernel build combinations. One build where
623 * ACPI is not selected in Kconfig and another one with the ACPI Kconfig.
624 *
625 * In the first case, vfio_platform_acpi_probe will return since
626 * acpi_disabled is 1. DT user will not see any kind of messages from
627 * ACPI.
628 *
629 * In the second case, both DT and ACPI is compiled in but the system is
630 * booting with any of these combinations.
631 *
632 * If the firmware is DT type, then acpi_disabled is 1. The ACPI probe routine
633 * terminates immediately without any messages.
634 *
635 * If the firmware is ACPI type, then acpi_disabled is 0. All other checks are
636 * valid checks. We cannot claim that this system is DT.
637 */
vfio_platform_init_common(struct vfio_platform_device * vdev)638 int vfio_platform_init_common(struct vfio_platform_device *vdev)
639 {
640 int ret;
641 struct device *dev = vdev->vdev.dev;
642
643 ret = vfio_platform_acpi_probe(vdev, dev);
644 if (ret)
645 ret = vfio_platform_of_probe(vdev, dev);
646
647 if (ret)
648 return ret;
649
650 vdev->device = dev;
651 mutex_init(&vdev->igate);
652
653 ret = vfio_platform_get_reset(vdev);
654 if (ret && vdev->reset_required)
655 dev_err(dev, "No reset function found for device %s\n",
656 vdev->name);
657 return ret;
658 }
659 EXPORT_SYMBOL_GPL(vfio_platform_init_common);
660
vfio_platform_release_common(struct vfio_platform_device * vdev)661 void vfio_platform_release_common(struct vfio_platform_device *vdev)
662 {
663 vfio_platform_put_reset(vdev);
664 }
665 EXPORT_SYMBOL_GPL(vfio_platform_release_common);
666
__vfio_platform_register_reset(struct vfio_platform_reset_node * node)667 void __vfio_platform_register_reset(struct vfio_platform_reset_node *node)
668 {
669 mutex_lock(&driver_lock);
670 list_add(&node->link, &reset_list);
671 mutex_unlock(&driver_lock);
672 }
673 EXPORT_SYMBOL_GPL(__vfio_platform_register_reset);
674
vfio_platform_unregister_reset(const char * compat,vfio_platform_reset_fn_t fn)675 void vfio_platform_unregister_reset(const char *compat,
676 vfio_platform_reset_fn_t fn)
677 {
678 struct vfio_platform_reset_node *iter, *temp;
679
680 mutex_lock(&driver_lock);
681 list_for_each_entry_safe(iter, temp, &reset_list, link) {
682 if (!strcmp(iter->compat, compat) && (iter->of_reset == fn)) {
683 list_del(&iter->link);
684 break;
685 }
686 }
687
688 mutex_unlock(&driver_lock);
689
690 }
691 EXPORT_SYMBOL_GPL(vfio_platform_unregister_reset);
692
693 MODULE_VERSION(DRIVER_VERSION);
694 MODULE_LICENSE("GPL v2");
695 MODULE_AUTHOR(DRIVER_AUTHOR);
696 MODULE_DESCRIPTION(DRIVER_DESC);
697
