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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(struct vfio_device *core_vdev)
222{
223 struct vfio_platform_device *vdev =
224 container_of(core_vdev, struct vfio_platform_device, vdev);
225
226 mutex_lock(&driver_lock);
227
228 if (!(--vdev->refcnt)) {
229 const char *extra_dbg = NULL;
230 int ret;
231
232 ret = vfio_platform_call_reset(vdev, &extra_dbg);
233 if (ret && vdev->reset_required) {
234 dev_warn(vdev->device, "reset driver is required and reset call failed in release (%d) %s\n",
235 ret, extra_dbg ? extra_dbg : "");
236 WARN_ON(1);
237 }
238 pm_runtime_put(vdev->device);
239 vfio_platform_regions_cleanup(vdev);
240 vfio_platform_irq_cleanup(vdev);
241 }
242
243 mutex_unlock(&driver_lock);
244}
245
246static int vfio_platform_open(struct vfio_device *core_vdev)
247{
248 struct vfio_platform_device *vdev =
249 container_of(core_vdev, struct vfio_platform_device, vdev);
250 int ret;
251
252 mutex_lock(&driver_lock);
253
254 if (!vdev->refcnt) {
255 const char *extra_dbg = NULL;
256
257 ret = vfio_platform_regions_init(vdev);
258 if (ret)
259 goto err_reg;
260
261 ret = vfio_platform_irq_init(vdev);
262 if (ret)
263 goto err_irq;
264
265 ret = pm_runtime_get_sync(vdev->device);
266 if (ret < 0)
267 goto err_rst;
268
269 ret = vfio_platform_call_reset(vdev, &extra_dbg);
270 if (ret && vdev->reset_required) {
271 dev_warn(vdev->device, "reset driver is required and reset call failed in open (%d) %s\n",
272 ret, extra_dbg ? extra_dbg : "");
273 goto err_rst;
274 }
275 }
276
277 vdev->refcnt++;
278
279 mutex_unlock(&driver_lock);
280 return 0;
281
282err_rst:
283 pm_runtime_put(vdev->device);
284 vfio_platform_irq_cleanup(vdev);
285err_irq:
286 vfio_platform_regions_cleanup(vdev);
287err_reg:
288 mutex_unlock(&driver_lock);
289 return ret;
290}
291
292static long vfio_platform_ioctl(struct vfio_device *core_vdev,
293 unsigned int cmd, unsigned long arg)
294{
295 struct vfio_platform_device *vdev =
296 container_of(core_vdev, struct vfio_platform_device, vdev);
297
298 unsigned long minsz;
299
300 if (cmd == VFIO_DEVICE_GET_INFO) {
301 struct vfio_device_info info;
302
303 minsz = offsetofend(struct vfio_device_info, num_irqs);
304
305 if (copy_from_user(&info, (void __user *)arg, minsz))
306 return -EFAULT;
307
308 if (info.argsz < minsz)
309 return -EINVAL;
310
311 if (vfio_platform_has_reset(vdev))
312 vdev->flags |= VFIO_DEVICE_FLAGS_RESET;
313 info.flags = vdev->flags;
314 info.num_regions = vdev->num_regions;
315 info.num_irqs = vdev->num_irqs;
316
317 return copy_to_user((void __user *)arg, &info, minsz) ?
318 -EFAULT : 0;
319
320 } else if (cmd == VFIO_DEVICE_GET_REGION_INFO) {
321 struct vfio_region_info info;
322
323 minsz = offsetofend(struct vfio_region_info, offset);
324
325 if (copy_from_user(&info, (void __user *)arg, minsz))
326 return -EFAULT;
327
328 if (info.argsz < minsz)
329 return -EINVAL;
330
331 if (info.index >= vdev->num_regions)
332 return -EINVAL;
333
334
335 info.offset = VFIO_PLATFORM_INDEX_TO_OFFSET(info.index);
336 info.size = vdev->regions[info.index].size;
337 info.flags = vdev->regions[info.index].flags;
338
339 return copy_to_user((void __user *)arg, &info, minsz) ?
340 -EFAULT : 0;
341
342 } else if (cmd == VFIO_DEVICE_GET_IRQ_INFO) {
343 struct vfio_irq_info info;
344
345 minsz = offsetofend(struct vfio_irq_info, count);
346
347 if (copy_from_user(&info, (void __user *)arg, minsz))
348 return -EFAULT;
349
350 if (info.argsz < minsz)
351 return -EINVAL;
352
353 if (info.index >= vdev->num_irqs)
354 return -EINVAL;
355
356 info.flags = vdev->irqs[info.index].flags;
357 info.count = vdev->irqs[info.index].count;
358
359 return copy_to_user((void __user *)arg, &info, minsz) ?
360 -EFAULT : 0;
361
362 } else if (cmd == VFIO_DEVICE_SET_IRQS) {
363 struct vfio_irq_set hdr;
364 u8 *data = NULL;
365 int ret = 0;
366 size_t data_size = 0;
367
368 minsz = offsetofend(struct vfio_irq_set, count);
369
370 if (copy_from_user(&hdr, (void __user *)arg, minsz))
371 return -EFAULT;
372
373 ret = vfio_set_irqs_validate_and_prepare(&hdr, vdev->num_irqs,
374 vdev->num_irqs, &data_size);
375 if (ret)
376 return ret;
377
378 if (data_size) {
379 data = memdup_user((void __user *)(arg + minsz),
380 data_size);
381 if (IS_ERR(data))
382 return PTR_ERR(data);
383 }
384
385 mutex_lock(&vdev->igate);
386
387 ret = vfio_platform_set_irqs_ioctl(vdev, hdr.flags, hdr.index,
388 hdr.start, hdr.count, data);
389 mutex_unlock(&vdev->igate);
390 kfree(data);
391
392 return ret;
393
394 } else if (cmd == VFIO_DEVICE_RESET) {
395 return vfio_platform_call_reset(vdev, NULL);
396 }
397
398 return -ENOTTY;
399}
400
401static ssize_t vfio_platform_read_mmio(struct vfio_platform_region *reg,
402 char __user *buf, size_t count,
403 loff_t off)
404{
405 unsigned int done = 0;
406
407 if (!reg->ioaddr) {
408 reg->ioaddr =
409 ioremap(reg->addr, reg->size);
410
411 if (!reg->ioaddr)
412 return -ENOMEM;
413 }
414
415 while (count) {
416 size_t filled;
417
418 if (count >= 4 && !(off % 4)) {
419 u32 val;
420
421 val = ioread32(reg->ioaddr + off);
422 if (copy_to_user(buf, &val, 4))
423 goto err;
424
425 filled = 4;
426 } else if (count >= 2 && !(off % 2)) {
427 u16 val;
428
429 val = ioread16(reg->ioaddr + off);
430 if (copy_to_user(buf, &val, 2))
431 goto err;
432
433 filled = 2;
434 } else {
435 u8 val;
436
437 val = ioread8(reg->ioaddr + off);
438 if (copy_to_user(buf, &val, 1))
439 goto err;
440
441 filled = 1;
442 }
443
444
445 count -= filled;
446 done += filled;
447 off += filled;
448 buf += filled;
449 }
450
451 return done;
452err:
453 return -EFAULT;
454}
455
456static ssize_t vfio_platform_read(struct vfio_device *core_vdev,
457 char __user *buf, size_t count, loff_t *ppos)
458{
459 struct vfio_platform_device *vdev =
460 container_of(core_vdev, struct vfio_platform_device, vdev);
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(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(struct vfio_device *core_vdev, const char __user *buf,
534 size_t count, loff_t *ppos)
535{
536 struct vfio_platform_device *vdev =
537 container_of(core_vdev, struct vfio_platform_device, vdev);
538 unsigned int index = VFIO_PLATFORM_OFFSET_TO_INDEX(*ppos);
539 loff_t off = *ppos & VFIO_PLATFORM_OFFSET_MASK;
540
541 if (index >= vdev->num_regions)
542 return -EINVAL;
543
544 if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_WRITE))
545 return -EINVAL;
546
547 if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_MMIO)
548 return vfio_platform_write_mmio(&vdev->regions[index],
549 buf, count, off);
550 else if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_PIO)
551 return -EINVAL;
552
553 return -EINVAL;
554}
555
556static int vfio_platform_mmap_mmio(struct vfio_platform_region region,
557 struct vm_area_struct *vma)
558{
559 u64 req_len, pgoff, req_start;
560
561 req_len = vma->vm_end - vma->vm_start;
562 pgoff = vma->vm_pgoff &
563 ((1U << (VFIO_PLATFORM_OFFSET_SHIFT - PAGE_SHIFT)) - 1);
564 req_start = pgoff << PAGE_SHIFT;
565
566 if (region.size < PAGE_SIZE || req_start + req_len > region.size)
567 return -EINVAL;
568
569 vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
570 vma->vm_pgoff = (region.addr >> PAGE_SHIFT) + pgoff;
571
572 return remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
573 req_len, vma->vm_page_prot);
574}
575
576static int vfio_platform_mmap(struct vfio_device *core_vdev, struct vm_area_struct *vma)
577{
578 struct vfio_platform_device *vdev =
579 container_of(core_vdev, struct vfio_platform_device, vdev);
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
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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 vfio_init_group_dev(&vdev->vdev, dev, &vfio_platform_ops);
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 dev_err(dev, "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 dev_err(dev, "No IOMMU group for device %s\n", vdev->name);
684 ret = -EINVAL;
685 goto put_reset;
686 }
687
688 ret = vfio_register_group_dev(&vdev->vdev);
689 if (ret)
690 goto put_iommu;
691
692 mutex_init(&vdev->igate);
693
694 pm_runtime_enable(dev);
695 return 0;
696
697put_iommu:
698 vfio_iommu_group_put(group, dev);
699put_reset:
700 vfio_platform_put_reset(vdev);
701 return ret;
702}
703EXPORT_SYMBOL_GPL(vfio_platform_probe_common);
704
705void vfio_platform_remove_common(struct vfio_platform_device *vdev)
706{
707 vfio_unregister_group_dev(&vdev->vdev);
708
709 pm_runtime_disable(vdev->device);
710 vfio_platform_put_reset(vdev);
711 vfio_iommu_group_put(vdev->vdev.dev->iommu_group, vdev->vdev.dev);
712}
713EXPORT_SYMBOL_GPL(vfio_platform_remove_common);
714
715void __vfio_platform_register_reset(struct vfio_platform_reset_node *node)
716{
717 mutex_lock(&driver_lock);
718 list_add(&node->link, &reset_list);
719 mutex_unlock(&driver_lock);
720}
721EXPORT_SYMBOL_GPL(__vfio_platform_register_reset);
722
723void vfio_platform_unregister_reset(const char *compat,
724 vfio_platform_reset_fn_t fn)
725{
726 struct vfio_platform_reset_node *iter, *temp;
727
728 mutex_lock(&driver_lock);
729 list_for_each_entry_safe(iter, temp, &reset_list, link) {
730 if (!strcmp(iter->compat, compat) && (iter->of_reset == fn)) {
731 list_del(&iter->link);
732 break;
733 }
734 }
735
736 mutex_unlock(&driver_lock);
737
738}
739EXPORT_SYMBOL_GPL(vfio_platform_unregister_reset);
740
741MODULE_VERSION(DRIVER_VERSION);
742MODULE_LICENSE("GPL v2");
743MODULE_AUTHOR(DRIVER_AUTHOR);
744MODULE_DESCRIPTION(DRIVER_DESC);
745
