1
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3
4
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
28static LIST_HEAD(reset_list);
29static DEFINE_MUTEX(driver_lock);
30
31static 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
50static 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
71static 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
93static 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
105static 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
113static 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
129static 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
138static 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
171
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;
190err:
191 kfree(vdev->regions);
192 return -EINVAL;
193}
194
195static 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
206static 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
221static void vfio_platform_release(void *device_data)
222{
223 struct vfio_platform_device *vdev = device_data;
224
225 mutex_lock(&driver_lock);
226
227 if (!(--vdev->refcnt)) {
228 const char *extra_dbg = NULL;
229 int ret;
230
231 ret = vfio_platform_call_reset(vdev, &extra_dbg);
232 if (ret && vdev->reset_required) {
233 dev_warn(vdev->device, "reset driver is required and reset call failed in release (%d) %s\n",
234 ret, extra_dbg ? extra_dbg : "");
235 WARN_ON(1);
236 }
237 pm_runtime_put(vdev->device);
238 vfio_platform_regions_cleanup(vdev);
239 vfio_platform_irq_cleanup(vdev);
240 }
241
242 mutex_unlock(&driver_lock);
243
244 module_put(vdev->parent_module);
245}
246
247static int vfio_platform_open(void *device_data)
248{
249 struct vfio_platform_device *vdev = device_data;
250 int ret;
251
252 if (!try_module_get(vdev->parent_module))
253 return -ENODEV;
254
255 mutex_lock(&driver_lock);
256
257 if (!vdev->refcnt) {
258 const char *extra_dbg = NULL;
259
260 ret = vfio_platform_regions_init(vdev);
261 if (ret)
262 goto err_reg;
263
264 ret = vfio_platform_irq_init(vdev);
265 if (ret)
266 goto err_irq;
267
268 ret = pm_runtime_get_sync(vdev->device);
269 if (ret < 0)
270 goto err_pm;
271
272 ret = vfio_platform_call_reset(vdev, &extra_dbg);
273 if (ret && vdev->reset_required) {
274 dev_warn(vdev->device, "reset driver is required and reset call failed in open (%d) %s\n",
275 ret, extra_dbg ? extra_dbg : "");
276 goto err_rst;
277 }
278 }
279
280 vdev->refcnt++;
281
282 mutex_unlock(&driver_lock);
283 return 0;
284
285err_rst:
286 pm_runtime_put(vdev->device);
287err_pm:
288 vfio_platform_irq_cleanup(vdev);
289err_irq:
290 vfio_platform_regions_cleanup(vdev);
291err_reg:
292 mutex_unlock(&driver_lock);
293 module_put(THIS_MODULE);
294 return ret;
295}
296
297static long vfio_platform_ioctl(void *device_data,
298 unsigned int cmd, unsigned long arg)
299{
300 struct vfio_platform_device *vdev = device_data;
301 unsigned long minsz;
302
303 if (cmd == VFIO_DEVICE_GET_INFO) {
304 struct vfio_device_info info;
305
306 minsz = offsetofend(struct vfio_device_info, num_irqs);
307
308 if (copy_from_user(&info, (void __user *)arg, minsz))
309 return -EFAULT;
310
311 if (info.argsz < minsz)
312 return -EINVAL;
313
314 if (vfio_platform_has_reset(vdev))
315 vdev->flags |= VFIO_DEVICE_FLAGS_RESET;
316 info.flags = vdev->flags;
317 info.num_regions = vdev->num_regions;
318 info.num_irqs = vdev->num_irqs;
319
320 return copy_to_user((void __user *)arg, &info, minsz) ?
321 -EFAULT : 0;
322
323 } else if (cmd == VFIO_DEVICE_GET_REGION_INFO) {
324 struct vfio_region_info info;
325
326 minsz = offsetofend(struct vfio_region_info, offset);
327
328 if (copy_from_user(&info, (void __user *)arg, minsz))
329 return -EFAULT;
330
331 if (info.argsz < minsz)
332 return -EINVAL;
333
334 if (info.index >= vdev->num_regions)
335 return -EINVAL;
336
337
338 info.offset = VFIO_PLATFORM_INDEX_TO_OFFSET(info.index);
339 info.size = vdev->regions[info.index].size;
340 info.flags = vdev->regions[info.index].flags;
341
342 return copy_to_user((void __user *)arg, &info, minsz) ?
343 -EFAULT : 0;
344
345 } else if (cmd == VFIO_DEVICE_GET_IRQ_INFO) {
346 struct vfio_irq_info info;
347
348 minsz = offsetofend(struct vfio_irq_info, count);
349
350 if (copy_from_user(&info, (void __user *)arg, minsz))
351 return -EFAULT;
352
353 if (info.argsz < minsz)
354 return -EINVAL;
355
356 if (info.index >= vdev->num_irqs)
357 return -EINVAL;
358
359 info.flags = vdev->irqs[info.index].flags;
360 info.count = vdev->irqs[info.index].count;
361
362 return copy_to_user((void __user *)arg, &info, minsz) ?
363 -EFAULT : 0;
364
365 } else if (cmd == VFIO_DEVICE_SET_IRQS) {
366 struct vfio_irq_set hdr;
367 u8 *data = NULL;
368 int ret = 0;
369 size_t data_size = 0;
370
371 minsz = offsetofend(struct vfio_irq_set, count);
372
373 if (copy_from_user(&hdr, (void __user *)arg, minsz))
374 return -EFAULT;
375
376 ret = vfio_set_irqs_validate_and_prepare(&hdr, vdev->num_irqs,
377 vdev->num_irqs, &data_size);
378 if (ret)
379 return ret;
380
381 if (data_size) {
382 data = memdup_user((void __user *)(arg + minsz),
383 data_size);
384 if (IS_ERR(data))
385 return PTR_ERR(data);
386 }
387
388 mutex_lock(&vdev->igate);
389
390 ret = vfio_platform_set_irqs_ioctl(vdev, hdr.flags, hdr.index,
391 hdr.start, hdr.count, data);
392 mutex_unlock(&vdev->igate);
393 kfree(data);
394
395 return ret;
396
397 } else if (cmd == VFIO_DEVICE_RESET) {
398 return vfio_platform_call_reset(vdev, NULL);
399 }
400
401 return -ENOTTY;
402}
403
404static ssize_t vfio_platform_read_mmio(struct vfio_platform_region *reg,
405 char __user *buf, size_t count,
406 loff_t off)
407{
408 unsigned int done = 0;
409
410 if (!reg->ioaddr) {
411 reg->ioaddr =
412 ioremap(reg->addr, reg->size);
413
414 if (!reg->ioaddr)
415 return -ENOMEM;
416 }
417
418 while (count) {
419 size_t filled;
420
421 if (count >= 4 && !(off % 4)) {
422 u32 val;
423
424 val = ioread32(reg->ioaddr + off);
425 if (copy_to_user(buf, &val, 4))
426 goto err;
427
428 filled = 4;
429 } else if (count >= 2 && !(off % 2)) {
430 u16 val;
431
432 val = ioread16(reg->ioaddr + off);
433 if (copy_to_user(buf, &val, 2))
434 goto err;
435
436 filled = 2;
437 } else {
438 u8 val;
439
440 val = ioread8(reg->ioaddr + off);
441 if (copy_to_user(buf, &val, 1))
442 goto err;
443
444 filled = 1;
445 }
446
447
448 count -= filled;
449 done += filled;
450 off += filled;
451 buf += filled;
452 }
453
454 return done;
455err:
456 return -EFAULT;
457}
458
459static ssize_t vfio_platform_read(void *device_data, char __user *buf,
460 size_t count, loff_t *ppos)
461{
462 struct vfio_platform_device *vdev = device_data;
463 unsigned int index = VFIO_PLATFORM_OFFSET_TO_INDEX(*ppos);
464 loff_t off = *ppos & VFIO_PLATFORM_OFFSET_MASK;
465
466 if (index >= vdev->num_regions)
467 return -EINVAL;
468
469 if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_READ))
470 return -EINVAL;
471
472 if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_MMIO)
473 return vfio_platform_read_mmio(&vdev->regions[index],
474 buf, count, off);
475 else if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_PIO)
476 return -EINVAL;
477
478 return -EINVAL;
479}
480
481static ssize_t vfio_platform_write_mmio(struct vfio_platform_region *reg,
482 const char __user *buf, size_t count,
483 loff_t off)
484{
485 unsigned int done = 0;
486
487 if (!reg->ioaddr) {
488 reg->ioaddr =
489 ioremap(reg->addr, reg->size);
490
491 if (!reg->ioaddr)
492 return -ENOMEM;
493 }
494
495 while (count) {
496 size_t filled;
497
498 if (count >= 4 && !(off % 4)) {
499 u32 val;
500
501 if (copy_from_user(&val, buf, 4))
502 goto err;
503 iowrite32(val, reg->ioaddr + off);
504
505 filled = 4;
506 } else if (count >= 2 && !(off % 2)) {
507 u16 val;
508
509 if (copy_from_user(&val, buf, 2))
510 goto err;
511 iowrite16(val, reg->ioaddr + off);
512
513 filled = 2;
514 } else {
515 u8 val;
516
517 if (copy_from_user(&val, buf, 1))
518 goto err;
519 iowrite8(val, reg->ioaddr + off);
520
521 filled = 1;
522 }
523
524 count -= filled;
525 done += filled;
526 off += filled;
527 buf += filled;
528 }
529
530 return done;
531err:
532 return -EFAULT;
533}
534
535static ssize_t vfio_platform_write(void *device_data, const char __user *buf,
536 size_t count, loff_t *ppos)
537{
538 struct vfio_platform_device *vdev = device_data;
539 unsigned int index = VFIO_PLATFORM_OFFSET_TO_INDEX(*ppos);
540 loff_t off = *ppos & VFIO_PLATFORM_OFFSET_MASK;
541
542 if (index >= vdev->num_regions)
543 return -EINVAL;
544
545 if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_WRITE))
546 return -EINVAL;
547
548 if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_MMIO)
549 return vfio_platform_write_mmio(&vdev->regions[index],
550 buf, count, off);
551 else if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_PIO)
552 return -EINVAL;
553
554 return -EINVAL;
555}
556
557static int vfio_platform_mmap_mmio(struct vfio_platform_region region,
558 struct vm_area_struct *vma)
559{
560 u64 req_len, pgoff, req_start;
561
562 req_len = vma->vm_end - vma->vm_start;
563 pgoff = vma->vm_pgoff &
564 ((1U << (VFIO_PLATFORM_OFFSET_SHIFT - PAGE_SHIFT)) - 1);
565 req_start = pgoff << PAGE_SHIFT;
566
567 if (region.size < PAGE_SIZE || req_start + req_len > region.size)
568 return -EINVAL;
569
570 vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
571 vma->vm_pgoff = (region.addr >> PAGE_SHIFT) + pgoff;
572
573 return remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
574 req_len, vma->vm_page_prot);
575}
576
577static int vfio_platform_mmap(void *device_data, struct vm_area_struct *vma)
578{
579 struct vfio_platform_device *vdev = device_data;
580 unsigned int index;
581
582 index = vma->vm_pgoff >> (VFIO_PLATFORM_OFFSET_SHIFT - PAGE_SHIFT);
583
584 if (vma->vm_end < vma->vm_start)
585 return -EINVAL;
586 if (!(vma->vm_flags & VM_SHARED))
587 return -EINVAL;
588 if (index >= vdev->num_regions)
589 return -EINVAL;
590 if (vma->vm_start & ~PAGE_MASK)
591 return -EINVAL;
592 if (vma->vm_end & ~PAGE_MASK)
593 return -EINVAL;
594
595 if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_MMAP))
596 return -EINVAL;
597
598 if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_READ)
599 && (vma->vm_flags & VM_READ))
600 return -EINVAL;
601
602 if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_WRITE)
603 && (vma->vm_flags & VM_WRITE))
604 return -EINVAL;
605
606 vma->vm_private_data = vdev;
607
608 if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_MMIO)
609 return vfio_platform_mmap_mmio(vdev->regions[index], vma);
610
611 else if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_PIO)
612 return -EINVAL;
613
614 return -EINVAL;
615}
616
617static const struct vfio_device_ops vfio_platform_ops = {
618 .name = "vfio-platform",
619 .open = vfio_platform_open,
620 .release = vfio_platform_release,
621 .ioctl = vfio_platform_ioctl,
622 .read = vfio_platform_read,
623 .write = vfio_platform_write,
624 .mmap = vfio_platform_mmap,
625};
626
627static int vfio_platform_of_probe(struct vfio_platform_device *vdev,
628 struct device *dev)
629{
630 int ret;
631
632 ret = device_property_read_string(dev, "compatible",
633 &vdev->compat);
634 if (ret)
635 dev_err(dev, "Cannot retrieve compat for %s\n", vdev->name);
636
637 return ret;
638}
639
640
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655
656
657int vfio_platform_probe_common(struct vfio_platform_device *vdev,
658 struct device *dev)
659{
660 struct iommu_group *group;
661 int ret;
662
663 if (!vdev)
664 return -EINVAL;
665
666 ret = vfio_platform_acpi_probe(vdev, dev);
667 if (ret)
668 ret = vfio_platform_of_probe(vdev, dev);
669
670 if (ret)
671 return ret;
672
673 vdev->device = dev;
674
675 ret = vfio_platform_get_reset(vdev);
676 if (ret && vdev->reset_required) {
677 dev_err(dev, "No reset function found for device %s\n",
678 vdev->name);
679 return ret;
680 }
681
682 group = vfio_iommu_group_get(dev);
683 if (!group) {
684 dev_err(dev, "No IOMMU group for device %s\n", vdev->name);
685 ret = -EINVAL;
686 goto put_reset;
687 }
688
689 ret = vfio_add_group_dev(dev, &vfio_platform_ops, vdev);
690 if (ret)
691 goto put_iommu;
692
693 mutex_init(&vdev->igate);
694
695 pm_runtime_enable(vdev->device);
696 return 0;
697
698put_iommu:
699 vfio_iommu_group_put(group, dev);
700put_reset:
701 vfio_platform_put_reset(vdev);
702 return ret;
703}
704EXPORT_SYMBOL_GPL(vfio_platform_probe_common);
705
706struct vfio_platform_device *vfio_platform_remove_common(struct device *dev)
707{
708 struct vfio_platform_device *vdev;
709
710 vdev = vfio_del_group_dev(dev);
711
712 if (vdev) {
713 pm_runtime_disable(vdev->device);
714 vfio_platform_put_reset(vdev);
715 vfio_iommu_group_put(dev->iommu_group, dev);
716 }
717
718 return vdev;
719}
720EXPORT_SYMBOL_GPL(vfio_platform_remove_common);
721
722void __vfio_platform_register_reset(struct vfio_platform_reset_node *node)
723{
724 mutex_lock(&driver_lock);
725 list_add(&node->link, &reset_list);
726 mutex_unlock(&driver_lock);
727}
728EXPORT_SYMBOL_GPL(__vfio_platform_register_reset);
729
730void vfio_platform_unregister_reset(const char *compat,
731 vfio_platform_reset_fn_t fn)
732{
733 struct vfio_platform_reset_node *iter, *temp;
734
735 mutex_lock(&driver_lock);
736 list_for_each_entry_safe(iter, temp, &reset_list, link) {
737 if (!strcmp(iter->compat, compat) && (iter->of_reset == fn)) {
738 list_del(&iter->link);
739 break;
740 }
741 }
742
743 mutex_unlock(&driver_lock);
744
745}
746EXPORT_SYMBOL_GPL(vfio_platform_unregister_reset);
747
748MODULE_VERSION(DRIVER_VERSION);
749MODULE_LICENSE("GPL v2");
750MODULE_AUTHOR(DRIVER_AUTHOR);
751MODULE_DESCRIPTION(DRIVER_DESC);
752
