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15#include <linux/device.h>
16#include <linux/iommu.h>
17#include <linux/module.h>
18#include <linux/mutex.h>
19#include <linux/slab.h>
20#include <linux/types.h>
21#include <linux/uaccess.h>
22#include <linux/vfio.h>
23
24#include "vfio_platform_private.h"
25
26#define DRIVER_VERSION "0.10"
27#define DRIVER_AUTHOR "Antonios Motakis <a.motakis@virtualopensystems.com>"
28#define DRIVER_DESC "VFIO platform base module"
29
30static LIST_HEAD(reset_list);
31static DEFINE_MUTEX(driver_lock);
32
33static vfio_platform_reset_fn_t vfio_platform_lookup_reset(const char *compat,
34 struct module **module)
35{
36 struct vfio_platform_reset_node *iter;
37 vfio_platform_reset_fn_t reset_fn = NULL;
38
39 mutex_lock(&driver_lock);
40 list_for_each_entry(iter, &reset_list, link) {
41 if (!strcmp(iter->compat, compat) &&
42 try_module_get(iter->owner)) {
43 *module = iter->owner;
44 reset_fn = iter->reset;
45 break;
46 }
47 }
48 mutex_unlock(&driver_lock);
49 return reset_fn;
50}
51
52static void vfio_platform_get_reset(struct vfio_platform_device *vdev)
53{
54 vdev->reset = vfio_platform_lookup_reset(vdev->compat,
55 &vdev->reset_module);
56 if (!vdev->reset) {
57 request_module("vfio-reset:%s", vdev->compat);
58 vdev->reset = vfio_platform_lookup_reset(vdev->compat,
59 &vdev->reset_module);
60 }
61}
62
63static void vfio_platform_put_reset(struct vfio_platform_device *vdev)
64{
65 if (vdev->reset)
66 module_put(vdev->reset_module);
67}
68
69static int vfio_platform_regions_init(struct vfio_platform_device *vdev)
70{
71 int cnt = 0, i;
72
73 while (vdev->get_resource(vdev, cnt))
74 cnt++;
75
76 vdev->regions = kcalloc(cnt, sizeof(struct vfio_platform_region),
77 GFP_KERNEL);
78 if (!vdev->regions)
79 return -ENOMEM;
80
81 for (i = 0; i < cnt; i++) {
82 struct resource *res =
83 vdev->get_resource(vdev, i);
84
85 if (!res)
86 goto err;
87
88 vdev->regions[i].addr = res->start;
89 vdev->regions[i].size = resource_size(res);
90 vdev->regions[i].flags = 0;
91
92 switch (resource_type(res)) {
93 case IORESOURCE_MEM:
94 vdev->regions[i].type = VFIO_PLATFORM_REGION_TYPE_MMIO;
95 vdev->regions[i].flags |= VFIO_REGION_INFO_FLAG_READ;
96 if (!(res->flags & IORESOURCE_READONLY))
97 vdev->regions[i].flags |=
98 VFIO_REGION_INFO_FLAG_WRITE;
99
100
101
102
103
104 if (!(vdev->regions[i].addr & ~PAGE_MASK) &&
105 !(vdev->regions[i].size & ~PAGE_MASK))
106 vdev->regions[i].flags |=
107 VFIO_REGION_INFO_FLAG_MMAP;
108
109 break;
110 case IORESOURCE_IO:
111 vdev->regions[i].type = VFIO_PLATFORM_REGION_TYPE_PIO;
112 break;
113 default:
114 goto err;
115 }
116 }
117
118 vdev->num_regions = cnt;
119
120 return 0;
121err:
122 kfree(vdev->regions);
123 return -EINVAL;
124}
125
126static void vfio_platform_regions_cleanup(struct vfio_platform_device *vdev)
127{
128 int i;
129
130 for (i = 0; i < vdev->num_regions; i++)
131 iounmap(vdev->regions[i].ioaddr);
132
133 vdev->num_regions = 0;
134 kfree(vdev->regions);
135}
136
137static void vfio_platform_release(void *device_data)
138{
139 struct vfio_platform_device *vdev = device_data;
140
141 mutex_lock(&driver_lock);
142
143 if (!(--vdev->refcnt)) {
144 if (vdev->reset) {
145 dev_info(vdev->device, "reset\n");
146 vdev->reset(vdev);
147 } else {
148 dev_warn(vdev->device, "no reset function found!\n");
149 }
150 vfio_platform_regions_cleanup(vdev);
151 vfio_platform_irq_cleanup(vdev);
152 }
153
154 mutex_unlock(&driver_lock);
155
156 module_put(vdev->parent_module);
157}
158
159static int vfio_platform_open(void *device_data)
160{
161 struct vfio_platform_device *vdev = device_data;
162 int ret;
163
164 if (!try_module_get(vdev->parent_module))
165 return -ENODEV;
166
167 mutex_lock(&driver_lock);
168
169 if (!vdev->refcnt) {
170 ret = vfio_platform_regions_init(vdev);
171 if (ret)
172 goto err_reg;
173
174 ret = vfio_platform_irq_init(vdev);
175 if (ret)
176 goto err_irq;
177
178 if (vdev->reset) {
179 dev_info(vdev->device, "reset\n");
180 vdev->reset(vdev);
181 } else {
182 dev_warn(vdev->device, "no reset function found!\n");
183 }
184 }
185
186 vdev->refcnt++;
187
188 mutex_unlock(&driver_lock);
189 return 0;
190
191err_irq:
192 vfio_platform_regions_cleanup(vdev);
193err_reg:
194 mutex_unlock(&driver_lock);
195 module_put(THIS_MODULE);
196 return ret;
197}
198
199static long vfio_platform_ioctl(void *device_data,
200 unsigned int cmd, unsigned long arg)
201{
202 struct vfio_platform_device *vdev = device_data;
203 unsigned long minsz;
204
205 if (cmd == VFIO_DEVICE_GET_INFO) {
206 struct vfio_device_info info;
207
208 minsz = offsetofend(struct vfio_device_info, num_irqs);
209
210 if (copy_from_user(&info, (void __user *)arg, minsz))
211 return -EFAULT;
212
213 if (info.argsz < minsz)
214 return -EINVAL;
215
216 if (vdev->reset)
217 vdev->flags |= VFIO_DEVICE_FLAGS_RESET;
218 info.flags = vdev->flags;
219 info.num_regions = vdev->num_regions;
220 info.num_irqs = vdev->num_irqs;
221
222 return copy_to_user((void __user *)arg, &info, minsz) ?
223 -EFAULT : 0;
224
225 } else if (cmd == VFIO_DEVICE_GET_REGION_INFO) {
226 struct vfio_region_info info;
227
228 minsz = offsetofend(struct vfio_region_info, offset);
229
230 if (copy_from_user(&info, (void __user *)arg, minsz))
231 return -EFAULT;
232
233 if (info.argsz < minsz)
234 return -EINVAL;
235
236 if (info.index >= vdev->num_regions)
237 return -EINVAL;
238
239
240 info.offset = VFIO_PLATFORM_INDEX_TO_OFFSET(info.index);
241 info.size = vdev->regions[info.index].size;
242 info.flags = vdev->regions[info.index].flags;
243
244 return copy_to_user((void __user *)arg, &info, minsz) ?
245 -EFAULT : 0;
246
247 } else if (cmd == VFIO_DEVICE_GET_IRQ_INFO) {
248 struct vfio_irq_info info;
249
250 minsz = offsetofend(struct vfio_irq_info, count);
251
252 if (copy_from_user(&info, (void __user *)arg, minsz))
253 return -EFAULT;
254
255 if (info.argsz < minsz)
256 return -EINVAL;
257
258 if (info.index >= vdev->num_irqs)
259 return -EINVAL;
260
261 info.flags = vdev->irqs[info.index].flags;
262 info.count = vdev->irqs[info.index].count;
263
264 return copy_to_user((void __user *)arg, &info, minsz) ?
265 -EFAULT : 0;
266
267 } else if (cmd == VFIO_DEVICE_SET_IRQS) {
268 struct vfio_irq_set hdr;
269 u8 *data = NULL;
270 int ret = 0;
271
272 minsz = offsetofend(struct vfio_irq_set, count);
273
274 if (copy_from_user(&hdr, (void __user *)arg, minsz))
275 return -EFAULT;
276
277 if (hdr.argsz < minsz)
278 return -EINVAL;
279
280 if (hdr.index >= vdev->num_irqs)
281 return -EINVAL;
282
283 if (hdr.flags & ~(VFIO_IRQ_SET_DATA_TYPE_MASK |
284 VFIO_IRQ_SET_ACTION_TYPE_MASK))
285 return -EINVAL;
286
287 if (!(hdr.flags & VFIO_IRQ_SET_DATA_NONE)) {
288 size_t size;
289
290 if (hdr.flags & VFIO_IRQ_SET_DATA_BOOL)
291 size = sizeof(uint8_t);
292 else if (hdr.flags & VFIO_IRQ_SET_DATA_EVENTFD)
293 size = sizeof(int32_t);
294 else
295 return -EINVAL;
296
297 if (hdr.argsz - minsz < size)
298 return -EINVAL;
299
300 data = memdup_user((void __user *)(arg + minsz), size);
301 if (IS_ERR(data))
302 return PTR_ERR(data);
303 }
304
305 mutex_lock(&vdev->igate);
306
307 ret = vfio_platform_set_irqs_ioctl(vdev, hdr.flags, hdr.index,
308 hdr.start, hdr.count, data);
309 mutex_unlock(&vdev->igate);
310 kfree(data);
311
312 return ret;
313
314 } else if (cmd == VFIO_DEVICE_RESET) {
315 if (vdev->reset)
316 return vdev->reset(vdev);
317 else
318 return -EINVAL;
319 }
320
321 return -ENOTTY;
322}
323
324static ssize_t vfio_platform_read_mmio(struct vfio_platform_region *reg,
325 char __user *buf, size_t count,
326 loff_t off)
327{
328 unsigned int done = 0;
329
330 if (!reg->ioaddr) {
331 reg->ioaddr =
332 ioremap_nocache(reg->addr, reg->size);
333
334 if (!reg->ioaddr)
335 return -ENOMEM;
336 }
337
338 while (count) {
339 size_t filled;
340
341 if (count >= 4 && !(off % 4)) {
342 u32 val;
343
344 val = ioread32(reg->ioaddr + off);
345 if (copy_to_user(buf, &val, 4))
346 goto err;
347
348 filled = 4;
349 } else if (count >= 2 && !(off % 2)) {
350 u16 val;
351
352 val = ioread16(reg->ioaddr + off);
353 if (copy_to_user(buf, &val, 2))
354 goto err;
355
356 filled = 2;
357 } else {
358 u8 val;
359
360 val = ioread8(reg->ioaddr + off);
361 if (copy_to_user(buf, &val, 1))
362 goto err;
363
364 filled = 1;
365 }
366
367
368 count -= filled;
369 done += filled;
370 off += filled;
371 buf += filled;
372 }
373
374 return done;
375err:
376 return -EFAULT;
377}
378
379static ssize_t vfio_platform_read(void *device_data, char __user *buf,
380 size_t count, loff_t *ppos)
381{
382 struct vfio_platform_device *vdev = device_data;
383 unsigned int index = VFIO_PLATFORM_OFFSET_TO_INDEX(*ppos);
384 loff_t off = *ppos & VFIO_PLATFORM_OFFSET_MASK;
385
386 if (index >= vdev->num_regions)
387 return -EINVAL;
388
389 if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_READ))
390 return -EINVAL;
391
392 if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_MMIO)
393 return vfio_platform_read_mmio(&vdev->regions[index],
394 buf, count, off);
395 else if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_PIO)
396 return -EINVAL;
397
398 return -EINVAL;
399}
400
401static ssize_t vfio_platform_write_mmio(struct vfio_platform_region *reg,
402 const 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_nocache(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 if (copy_from_user(&val, buf, 4))
422 goto err;
423 iowrite32(val, reg->ioaddr + off);
424
425 filled = 4;
426 } else if (count >= 2 && !(off % 2)) {
427 u16 val;
428
429 if (copy_from_user(&val, buf, 2))
430 goto err;
431 iowrite16(val, reg->ioaddr + off);
432
433 filled = 2;
434 } else {
435 u8 val;
436
437 if (copy_from_user(&val, buf, 1))
438 goto err;
439 iowrite8(val, reg->ioaddr + off);
440
441 filled = 1;
442 }
443
444 count -= filled;
445 done += filled;
446 off += filled;
447 buf += filled;
448 }
449
450 return done;
451err:
452 return -EFAULT;
453}
454
455static ssize_t vfio_platform_write(void *device_data, const char __user *buf,
456 size_t count, loff_t *ppos)
457{
458 struct vfio_platform_device *vdev = device_data;
459 unsigned int index = VFIO_PLATFORM_OFFSET_TO_INDEX(*ppos);
460 loff_t off = *ppos & VFIO_PLATFORM_OFFSET_MASK;
461
462 if (index >= vdev->num_regions)
463 return -EINVAL;
464
465 if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_WRITE))
466 return -EINVAL;
467
468 if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_MMIO)
469 return vfio_platform_write_mmio(&vdev->regions[index],
470 buf, count, off);
471 else if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_PIO)
472 return -EINVAL;
473
474 return -EINVAL;
475}
476
477static int vfio_platform_mmap_mmio(struct vfio_platform_region region,
478 struct vm_area_struct *vma)
479{
480 u64 req_len, pgoff, req_start;
481
482 req_len = vma->vm_end - vma->vm_start;
483 pgoff = vma->vm_pgoff &
484 ((1U << (VFIO_PLATFORM_OFFSET_SHIFT - PAGE_SHIFT)) - 1);
485 req_start = pgoff << PAGE_SHIFT;
486
487 if (region.size < PAGE_SIZE || req_start + req_len > region.size)
488 return -EINVAL;
489
490 vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
491 vma->vm_pgoff = (region.addr >> PAGE_SHIFT) + pgoff;
492
493 return remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
494 req_len, vma->vm_page_prot);
495}
496
497static int vfio_platform_mmap(void *device_data, struct vm_area_struct *vma)
498{
499 struct vfio_platform_device *vdev = device_data;
500 unsigned int index;
501
502 index = vma->vm_pgoff >> (VFIO_PLATFORM_OFFSET_SHIFT - PAGE_SHIFT);
503
504 if (vma->vm_end < vma->vm_start)
505 return -EINVAL;
506 if (!(vma->vm_flags & VM_SHARED))
507 return -EINVAL;
508 if (index >= vdev->num_regions)
509 return -EINVAL;
510 if (vma->vm_start & ~PAGE_MASK)
511 return -EINVAL;
512 if (vma->vm_end & ~PAGE_MASK)
513 return -EINVAL;
514
515 if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_MMAP))
516 return -EINVAL;
517
518 if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_READ)
519 && (vma->vm_flags & VM_READ))
520 return -EINVAL;
521
522 if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_WRITE)
523 && (vma->vm_flags & VM_WRITE))
524 return -EINVAL;
525
526 vma->vm_private_data = vdev;
527
528 if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_MMIO)
529 return vfio_platform_mmap_mmio(vdev->regions[index], vma);
530
531 else if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_PIO)
532 return -EINVAL;
533
534 return -EINVAL;
535}
536
537static const struct vfio_device_ops vfio_platform_ops = {
538 .name = "vfio-platform",
539 .open = vfio_platform_open,
540 .release = vfio_platform_release,
541 .ioctl = vfio_platform_ioctl,
542 .read = vfio_platform_read,
543 .write = vfio_platform_write,
544 .mmap = vfio_platform_mmap,
545};
546
547int vfio_platform_probe_common(struct vfio_platform_device *vdev,
548 struct device *dev)
549{
550 struct iommu_group *group;
551 int ret;
552
553 if (!vdev)
554 return -EINVAL;
555
556 ret = device_property_read_string(dev, "compatible", &vdev->compat);
557 if (ret) {
558 pr_err("VFIO: cannot retrieve compat for %s\n", vdev->name);
559 return -EINVAL;
560 }
561
562 vdev->device = dev;
563
564 group = iommu_group_get(dev);
565 if (!group) {
566 pr_err("VFIO: No IOMMU group for device %s\n", vdev->name);
567 return -EINVAL;
568 }
569
570 ret = vfio_add_group_dev(dev, &vfio_platform_ops, vdev);
571 if (ret) {
572 iommu_group_put(group);
573 return ret;
574 }
575
576 vfio_platform_get_reset(vdev);
577
578 mutex_init(&vdev->igate);
579
580 return 0;
581}
582EXPORT_SYMBOL_GPL(vfio_platform_probe_common);
583
584struct vfio_platform_device *vfio_platform_remove_common(struct device *dev)
585{
586 struct vfio_platform_device *vdev;
587
588 vdev = vfio_del_group_dev(dev);
589
590 if (vdev) {
591 vfio_platform_put_reset(vdev);
592 iommu_group_put(dev->iommu_group);
593 }
594
595 return vdev;
596}
597EXPORT_SYMBOL_GPL(vfio_platform_remove_common);
598
599void __vfio_platform_register_reset(struct vfio_platform_reset_node *node)
600{
601 mutex_lock(&driver_lock);
602 list_add(&node->link, &reset_list);
603 mutex_unlock(&driver_lock);
604}
605EXPORT_SYMBOL_GPL(__vfio_platform_register_reset);
606
607void vfio_platform_unregister_reset(const char *compat,
608 vfio_platform_reset_fn_t fn)
609{
610 struct vfio_platform_reset_node *iter, *temp;
611
612 mutex_lock(&driver_lock);
613 list_for_each_entry_safe(iter, temp, &reset_list, link) {
614 if (!strcmp(iter->compat, compat) && (iter->reset == fn)) {
615 list_del(&iter->link);
616 break;
617 }
618 }
619
620 mutex_unlock(&driver_lock);
621
622}
623EXPORT_SYMBOL_GPL(vfio_platform_unregister_reset);
624
625MODULE_VERSION(DRIVER_VERSION);
626MODULE_LICENSE("GPL v2");
627MODULE_AUTHOR(DRIVER_AUTHOR);
628MODULE_DESCRIPTION(DRIVER_DESC);
629
