1
2
3
4
5
6
7
8
9
10
11
12
13
14
15#include <linux/device.h>
16#include <linux/acpi.h>
17#include <linux/iommu.h>
18#include <linux/module.h>
19#include <linux/mutex.h>
20#include <linux/slab.h>
21#include <linux/types.h>
22#include <linux/uaccess.h>
23#include <linux/vfio.h>
24
25#include "vfio_platform_private.h"
26
27#define DRIVER_VERSION "0.10"
28#define DRIVER_AUTHOR "Antonios Motakis <a.motakis@virtualopensystems.com>"
29#define DRIVER_DESC "VFIO platform base module"
30
31#define VFIO_PLATFORM_IS_ACPI(vdev) ((vdev)->acpihid != NULL)
32
33static LIST_HEAD(reset_list);
34static DEFINE_MUTEX(driver_lock);
35
36static vfio_platform_reset_fn_t vfio_platform_lookup_reset(const char *compat,
37 struct module **module)
38{
39 struct vfio_platform_reset_node *iter;
40 vfio_platform_reset_fn_t reset_fn = NULL;
41
42 mutex_lock(&driver_lock);
43 list_for_each_entry(iter, &reset_list, link) {
44 if (!strcmp(iter->compat, compat) &&
45 try_module_get(iter->owner)) {
46 *module = iter->owner;
47 reset_fn = iter->of_reset;
48 break;
49 }
50 }
51 mutex_unlock(&driver_lock);
52 return reset_fn;
53}
54
55static int vfio_platform_acpi_probe(struct vfio_platform_device *vdev,
56 struct device *dev)
57{
58 struct acpi_device *adev;
59
60 if (acpi_disabled)
61 return -ENOENT;
62
63 adev = ACPI_COMPANION(dev);
64 if (!adev) {
65 pr_err("VFIO: ACPI companion device not found for %s\n",
66 vdev->name);
67 return -ENODEV;
68 }
69
70#ifdef CONFIG_ACPI
71 vdev->acpihid = acpi_device_hid(adev);
72#endif
73 return WARN_ON(!vdev->acpihid) ? -EINVAL : 0;
74}
75
76static int vfio_platform_acpi_call_reset(struct vfio_platform_device *vdev,
77 const char **extra_dbg)
78{
79#ifdef CONFIG_ACPI
80 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
81 struct device *dev = vdev->device;
82 acpi_handle handle = ACPI_HANDLE(dev);
83 acpi_status acpi_ret;
84
85 acpi_ret = acpi_evaluate_object(handle, "_RST", NULL, &buffer);
86 if (ACPI_FAILURE(acpi_ret)) {
87 if (extra_dbg)
88 *extra_dbg = acpi_format_exception(acpi_ret);
89 return -EINVAL;
90 }
91
92 return 0;
93#else
94 return -ENOENT;
95#endif
96}
97
98static bool vfio_platform_acpi_has_reset(struct vfio_platform_device *vdev)
99{
100#ifdef CONFIG_ACPI
101 struct device *dev = vdev->device;
102 acpi_handle handle = ACPI_HANDLE(dev);
103
104 return acpi_has_method(handle, "_RST");
105#else
106 return false;
107#endif
108}
109
110static bool vfio_platform_has_reset(struct vfio_platform_device *vdev)
111{
112 if (VFIO_PLATFORM_IS_ACPI(vdev))
113 return vfio_platform_acpi_has_reset(vdev);
114
115 return vdev->of_reset ? true : false;
116}
117
118static int vfio_platform_get_reset(struct vfio_platform_device *vdev)
119{
120 if (VFIO_PLATFORM_IS_ACPI(vdev))
121 return vfio_platform_acpi_has_reset(vdev) ? 0 : -ENOENT;
122
123 vdev->of_reset = vfio_platform_lookup_reset(vdev->compat,
124 &vdev->reset_module);
125 if (!vdev->of_reset) {
126 request_module("vfio-reset:%s", vdev->compat);
127 vdev->of_reset = vfio_platform_lookup_reset(vdev->compat,
128 &vdev->reset_module);
129 }
130
131 return vdev->of_reset ? 0 : -ENOENT;
132}
133
134static void vfio_platform_put_reset(struct vfio_platform_device *vdev)
135{
136 if (VFIO_PLATFORM_IS_ACPI(vdev))
137 return;
138
139 if (vdev->of_reset)
140 module_put(vdev->reset_module);
141}
142
143static int vfio_platform_regions_init(struct vfio_platform_device *vdev)
144{
145 int cnt = 0, i;
146
147 while (vdev->get_resource(vdev, cnt))
148 cnt++;
149
150 vdev->regions = kcalloc(cnt, sizeof(struct vfio_platform_region),
151 GFP_KERNEL);
152 if (!vdev->regions)
153 return -ENOMEM;
154
155 for (i = 0; i < cnt; i++) {
156 struct resource *res =
157 vdev->get_resource(vdev, i);
158
159 if (!res)
160 goto err;
161
162 vdev->regions[i].addr = res->start;
163 vdev->regions[i].size = resource_size(res);
164 vdev->regions[i].flags = 0;
165
166 switch (resource_type(res)) {
167 case IORESOURCE_MEM:
168 vdev->regions[i].type = VFIO_PLATFORM_REGION_TYPE_MMIO;
169 vdev->regions[i].flags |= VFIO_REGION_INFO_FLAG_READ;
170 if (!(res->flags & IORESOURCE_READONLY))
171 vdev->regions[i].flags |=
172 VFIO_REGION_INFO_FLAG_WRITE;
173
174
175
176
177
178 if (!(vdev->regions[i].addr & ~PAGE_MASK) &&
179 !(vdev->regions[i].size & ~PAGE_MASK))
180 vdev->regions[i].flags |=
181 VFIO_REGION_INFO_FLAG_MMAP;
182
183 break;
184 case IORESOURCE_IO:
185 vdev->regions[i].type = VFIO_PLATFORM_REGION_TYPE_PIO;
186 break;
187 default:
188 goto err;
189 }
190 }
191
192 vdev->num_regions = cnt;
193
194 return 0;
195err:
196 kfree(vdev->regions);
197 return -EINVAL;
198}
199
200static void vfio_platform_regions_cleanup(struct vfio_platform_device *vdev)
201{
202 int i;
203
204 for (i = 0; i < vdev->num_regions; i++)
205 iounmap(vdev->regions[i].ioaddr);
206
207 vdev->num_regions = 0;
208 kfree(vdev->regions);
209}
210
211static int vfio_platform_call_reset(struct vfio_platform_device *vdev,
212 const char **extra_dbg)
213{
214 if (VFIO_PLATFORM_IS_ACPI(vdev)) {
215 dev_info(vdev->device, "reset\n");
216 return vfio_platform_acpi_call_reset(vdev, extra_dbg);
217 } else if (vdev->of_reset) {
218 dev_info(vdev->device, "reset\n");
219 return vdev->of_reset(vdev);
220 }
221
222 dev_warn(vdev->device, "no reset function found!\n");
223 return -EINVAL;
224}
225
226static void vfio_platform_release(void *device_data)
227{
228 struct vfio_platform_device *vdev = device_data;
229
230 mutex_lock(&driver_lock);
231
232 if (!(--vdev->refcnt)) {
233 const char *extra_dbg = NULL;
234 int ret;
235
236 ret = vfio_platform_call_reset(vdev, &extra_dbg);
237 if (ret && vdev->reset_required) {
238 dev_warn(vdev->device, "reset driver is required and reset call failed in release (%d) %s\n",
239 ret, extra_dbg ? extra_dbg : "");
240 WARN_ON(1);
241 }
242 vfio_platform_regions_cleanup(vdev);
243 vfio_platform_irq_cleanup(vdev);
244 }
245
246 mutex_unlock(&driver_lock);
247
248 module_put(vdev->parent_module);
249}
250
251static int vfio_platform_open(void *device_data)
252{
253 struct vfio_platform_device *vdev = device_data;
254 int ret;
255
256 if (!try_module_get(vdev->parent_module))
257 return -ENODEV;
258
259 mutex_lock(&driver_lock);
260
261 if (!vdev->refcnt) {
262 const char *extra_dbg = NULL;
263
264 ret = vfio_platform_regions_init(vdev);
265 if (ret)
266 goto err_reg;
267
268 ret = vfio_platform_irq_init(vdev);
269 if (ret)
270 goto err_irq;
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 vfio_platform_irq_cleanup(vdev);
287err_irq:
288 vfio_platform_regions_cleanup(vdev);
289err_reg:
290 mutex_unlock(&driver_lock);
291 module_put(THIS_MODULE);
292 return ret;
293}
294
295static long vfio_platform_ioctl(void *device_data,
296 unsigned int cmd, unsigned long arg)
297{
298 struct vfio_platform_device *vdev = device_data;
299 unsigned long minsz;
300
301 if (cmd == VFIO_DEVICE_GET_INFO) {
302 struct vfio_device_info info;
303
304 minsz = offsetofend(struct vfio_device_info, num_irqs);
305
306 if (copy_from_user(&info, (void __user *)arg, minsz))
307 return -EFAULT;
308
309 if (info.argsz < minsz)
310 return -EINVAL;
311
312 if (vfio_platform_has_reset(vdev))
313 vdev->flags |= VFIO_DEVICE_FLAGS_RESET;
314 info.flags = vdev->flags;
315 info.num_regions = vdev->num_regions;
316 info.num_irqs = vdev->num_irqs;
317
318 return copy_to_user((void __user *)arg, &info, minsz) ?
319 -EFAULT : 0;
320
321 } else if (cmd == VFIO_DEVICE_GET_REGION_INFO) {
322 struct vfio_region_info info;
323
324 minsz = offsetofend(struct vfio_region_info, offset);
325
326 if (copy_from_user(&info, (void __user *)arg, minsz))
327 return -EFAULT;
328
329 if (info.argsz < minsz)
330 return -EINVAL;
331
332 if (info.index >= vdev->num_regions)
333 return -EINVAL;
334
335
336 info.offset = VFIO_PLATFORM_INDEX_TO_OFFSET(info.index);
337 info.size = vdev->regions[info.index].size;
338 info.flags = vdev->regions[info.index].flags;
339
340 return copy_to_user((void __user *)arg, &info, minsz) ?
341 -EFAULT : 0;
342
343 } else if (cmd == VFIO_DEVICE_GET_IRQ_INFO) {
344 struct vfio_irq_info info;
345
346 minsz = offsetofend(struct vfio_irq_info, count);
347
348 if (copy_from_user(&info, (void __user *)arg, minsz))
349 return -EFAULT;
350
351 if (info.argsz < minsz)
352 return -EINVAL;
353
354 if (info.index >= vdev->num_irqs)
355 return -EINVAL;
356
357 info.flags = vdev->irqs[info.index].flags;
358 info.count = vdev->irqs[info.index].count;
359
360 return copy_to_user((void __user *)arg, &info, minsz) ?
361 -EFAULT : 0;
362
363 } else if (cmd == VFIO_DEVICE_SET_IRQS) {
364 struct vfio_irq_set hdr;
365 u8 *data = NULL;
366 int ret = 0;
367 size_t data_size = 0;
368
369 minsz = offsetofend(struct vfio_irq_set, count);
370
371 if (copy_from_user(&hdr, (void __user *)arg, minsz))
372 return -EFAULT;
373
374 ret = vfio_set_irqs_validate_and_prepare(&hdr, vdev->num_irqs,
375 vdev->num_irqs, &data_size);
376 if (ret)
377 return ret;
378
379 if (data_size) {
380 data = memdup_user((void __user *)(arg + minsz),
381 data_size);
382 if (IS_ERR(data))
383 return PTR_ERR(data);
384 }
385
386 mutex_lock(&vdev->igate);
387
388 ret = vfio_platform_set_irqs_ioctl(vdev, hdr.flags, hdr.index,
389 hdr.start, hdr.count, data);
390 mutex_unlock(&vdev->igate);
391 kfree(data);
392
393 return ret;
394
395 } else if (cmd == VFIO_DEVICE_RESET) {
396 return vfio_platform_call_reset(vdev, NULL);
397 }
398
399 return -ENOTTY;
400}
401
402static ssize_t vfio_platform_read_mmio(struct vfio_platform_region *reg,
403 char __user *buf, size_t count,
404 loff_t off)
405{
406 unsigned int done = 0;
407
408 if (!reg->ioaddr) {
409 reg->ioaddr =
410 ioremap_nocache(reg->addr, reg->size);
411
412 if (!reg->ioaddr)
413 return -ENOMEM;
414 }
415
416 while (count) {
417 size_t filled;
418
419 if (count >= 4 && !(off % 4)) {
420 u32 val;
421
422 val = ioread32(reg->ioaddr + off);
423 if (copy_to_user(buf, &val, 4))
424 goto err;
425
426 filled = 4;
427 } else if (count >= 2 && !(off % 2)) {
428 u16 val;
429
430 val = ioread16(reg->ioaddr + off);
431 if (copy_to_user(buf, &val, 2))
432 goto err;
433
434 filled = 2;
435 } else {
436 u8 val;
437
438 val = ioread8(reg->ioaddr + off);
439 if (copy_to_user(buf, &val, 1))
440 goto err;
441
442 filled = 1;
443 }
444
445
446 count -= filled;
447 done += filled;
448 off += filled;
449 buf += filled;
450 }
451
452 return done;
453err:
454 return -EFAULT;
455}
456
457static ssize_t vfio_platform_read(void *device_data, char __user *buf,
458 size_t count, loff_t *ppos)
459{
460 struct vfio_platform_device *vdev = device_data;
461 unsigned int index = VFIO_PLATFORM_OFFSET_TO_INDEX(*ppos);
462 loff_t off = *ppos & VFIO_PLATFORM_OFFSET_MASK;
463
464 if (index >= vdev->num_regions)
465 return -EINVAL;
466
467 if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_READ))
468 return -EINVAL;
469
470 if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_MMIO)
471 return vfio_platform_read_mmio(&vdev->regions[index],
472 buf, count, off);
473 else if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_PIO)
474 return -EINVAL;
475
476 return -EINVAL;
477}
478
479static ssize_t vfio_platform_write_mmio(struct vfio_platform_region *reg,
480 const char __user *buf, size_t count,
481 loff_t off)
482{
483 unsigned int done = 0;
484
485 if (!reg->ioaddr) {
486 reg->ioaddr =
487 ioremap_nocache(reg->addr, reg->size);
488
489 if (!reg->ioaddr)
490 return -ENOMEM;
491 }
492
493 while (count) {
494 size_t filled;
495
496 if (count >= 4 && !(off % 4)) {
497 u32 val;
498
499 if (copy_from_user(&val, buf, 4))
500 goto err;
501 iowrite32(val, reg->ioaddr + off);
502
503 filled = 4;
504 } else if (count >= 2 && !(off % 2)) {
505 u16 val;
506
507 if (copy_from_user(&val, buf, 2))
508 goto err;
509 iowrite16(val, reg->ioaddr + off);
510
511 filled = 2;
512 } else {
513 u8 val;
514
515 if (copy_from_user(&val, buf, 1))
516 goto err;
517 iowrite8(val, reg->ioaddr + off);
518
519 filled = 1;
520 }
521
522 count -= filled;
523 done += filled;
524 off += filled;
525 buf += filled;
526 }
527
528 return done;
529err:
530 return -EFAULT;
531}
532
533static ssize_t vfio_platform_write(void *device_data, const char __user *buf,
534 size_t count, loff_t *ppos)
535{
536 struct vfio_platform_device *vdev = device_data;
537 unsigned int index = VFIO_PLATFORM_OFFSET_TO_INDEX(*ppos);
538 loff_t off = *ppos & VFIO_PLATFORM_OFFSET_MASK;
539
540 if (index >= vdev->num_regions)
541 return -EINVAL;
542
543 if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_WRITE))
544 return -EINVAL;
545
546 if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_MMIO)
547 return vfio_platform_write_mmio(&vdev->regions[index],
548 buf, count, off);
549 else if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_PIO)
550 return -EINVAL;
551
552 return -EINVAL;
553}
554
555static int vfio_platform_mmap_mmio(struct vfio_platform_region region,
556 struct vm_area_struct *vma)
557{
558 u64 req_len, pgoff, req_start;
559
560 req_len = vma->vm_end - vma->vm_start;
561 pgoff = vma->vm_pgoff &
562 ((1U << (VFIO_PLATFORM_OFFSET_SHIFT - PAGE_SHIFT)) - 1);
563 req_start = pgoff << PAGE_SHIFT;
564
565 if (region.size < PAGE_SIZE || req_start + req_len > region.size)
566 return -EINVAL;
567
568 vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
569 vma->vm_pgoff = (region.addr >> PAGE_SHIFT) + pgoff;
570
571 return remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
572 req_len, vma->vm_page_prot);
573}
574
575static int vfio_platform_mmap(void *device_data, struct vm_area_struct *vma)
576{
577 struct vfio_platform_device *vdev = device_data;
578 unsigned int index;
579
580 index = vma->vm_pgoff >> (VFIO_PLATFORM_OFFSET_SHIFT - PAGE_SHIFT);
581
582 if (vma->vm_end < vma->vm_start)
583 return -EINVAL;
584 if (!(vma->vm_flags & VM_SHARED))
585 return -EINVAL;
586 if (index >= vdev->num_regions)
587 return -EINVAL;
588 if (vma->vm_start & ~PAGE_MASK)
589 return -EINVAL;
590 if (vma->vm_end & ~PAGE_MASK)
591 return -EINVAL;
592
593 if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_MMAP))
594 return -EINVAL;
595
596 if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_READ)
597 && (vma->vm_flags & VM_READ))
598 return -EINVAL;
599
600 if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_WRITE)
601 && (vma->vm_flags & VM_WRITE))
602 return -EINVAL;
603
604 vma->vm_private_data = vdev;
605
606 if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_MMIO)
607 return vfio_platform_mmap_mmio(vdev->regions[index], vma);
608
609 else if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_PIO)
610 return -EINVAL;
611
612 return -EINVAL;
613}
614
615static const struct vfio_device_ops vfio_platform_ops = {
616 .name = "vfio-platform",
617 .open = vfio_platform_open,
618 .release = vfio_platform_release,
619 .ioctl = vfio_platform_ioctl,
620 .read = vfio_platform_read,
621 .write = vfio_platform_write,
622 .mmap = vfio_platform_mmap,
623};
624
625static int vfio_platform_of_probe(struct vfio_platform_device *vdev,
626 struct device *dev)
627{
628 int ret;
629
630 ret = device_property_read_string(dev, "compatible",
631 &vdev->compat);
632 if (ret)
633 pr_err("VFIO: cannot retrieve compat for %s\n",
634 vdev->name);
635
636 return ret;
637}
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656int vfio_platform_probe_common(struct vfio_platform_device *vdev,
657 struct device *dev)
658{
659 struct iommu_group *group;
660 int ret;
661
662 if (!vdev)
663 return -EINVAL;
664
665 ret = vfio_platform_acpi_probe(vdev, dev);
666 if (ret)
667 ret = vfio_platform_of_probe(vdev, dev);
668
669 if (ret)
670 return ret;
671
672 vdev->device = dev;
673
674 ret = vfio_platform_get_reset(vdev);
675 if (ret && vdev->reset_required) {
676 pr_err("vfio: no reset function found for device %s\n",
677 vdev->name);
678 return ret;
679 }
680
681 group = vfio_iommu_group_get(dev);
682 if (!group) {
683 pr_err("VFIO: No IOMMU group for device %s\n", vdev->name);
684 return -EINVAL;
685 }
686
687 ret = vfio_add_group_dev(dev, &vfio_platform_ops, vdev);
688 if (ret) {
689 vfio_iommu_group_put(group, dev);
690 return ret;
691 }
692
693 mutex_init(&vdev->igate);
694
695 return 0;
696}
697EXPORT_SYMBOL_GPL(vfio_platform_probe_common);
698
699struct vfio_platform_device *vfio_platform_remove_common(struct device *dev)
700{
701 struct vfio_platform_device *vdev;
702
703 vdev = vfio_del_group_dev(dev);
704
705 if (vdev) {
706 vfio_platform_put_reset(vdev);
707 vfio_iommu_group_put(dev->iommu_group, dev);
708 }
709
710 return vdev;
711}
712EXPORT_SYMBOL_GPL(vfio_platform_remove_common);
713
714void __vfio_platform_register_reset(struct vfio_platform_reset_node *node)
715{
716 mutex_lock(&driver_lock);
717 list_add(&node->link, &reset_list);
718 mutex_unlock(&driver_lock);
719}
720EXPORT_SYMBOL_GPL(__vfio_platform_register_reset);
721
722void vfio_platform_unregister_reset(const char *compat,
723 vfio_platform_reset_fn_t fn)
724{
725 struct vfio_platform_reset_node *iter, *temp;
726
727 mutex_lock(&driver_lock);
728 list_for_each_entry_safe(iter, temp, &reset_list, link) {
729 if (!strcmp(iter->compat, compat) && (iter->of_reset == fn)) {
730 list_del(&iter->link);
731 break;
732 }
733 }
734
735 mutex_unlock(&driver_lock);
736
737}
738EXPORT_SYMBOL_GPL(vfio_platform_unregister_reset);
739
740MODULE_VERSION(DRIVER_VERSION);
741MODULE_LICENSE("GPL v2");
742MODULE_AUTHOR(DRIVER_AUTHOR);
743MODULE_DESCRIPTION(DRIVER_DESC);
744
