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v6.8
  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
 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 device *dev = vdev->device;
 76	acpi_handle handle = ACPI_HANDLE(dev);
 77	acpi_status acpi_ret;
 78
 79	acpi_ret = acpi_evaluate_object(handle, "_RST", NULL, NULL);
 80	if (ACPI_FAILURE(acpi_ret)) {
 81		if (extra_dbg)
 82			*extra_dbg = acpi_format_exception(acpi_ret);
 83		return -EINVAL;
 84	}
 85
 86	return 0;
 87#else
 88	return -ENOENT;
 89#endif
 90}
 91
 92static bool vfio_platform_acpi_has_reset(struct vfio_platform_device *vdev)
 93{
 94#ifdef CONFIG_ACPI
 95	struct device *dev = vdev->device;
 96	acpi_handle handle = ACPI_HANDLE(dev);
 97
 98	return acpi_has_method(handle, "_RST");
 99#else
100	return false;
101#endif
102}
103
104static bool vfio_platform_has_reset(struct vfio_platform_device *vdev)
105{
106	if (VFIO_PLATFORM_IS_ACPI(vdev))
107		return vfio_platform_acpi_has_reset(vdev);
108
109	return vdev->of_reset ? true : false;
110}
111
112static int vfio_platform_get_reset(struct vfio_platform_device *vdev)
113{
114	if (VFIO_PLATFORM_IS_ACPI(vdev))
115		return vfio_platform_acpi_has_reset(vdev) ? 0 : -ENOENT;
116
117	vdev->of_reset = vfio_platform_lookup_reset(vdev->compat,
118						    &vdev->reset_module);
119	if (!vdev->of_reset) {
120		request_module("vfio-reset:%s", vdev->compat);
121		vdev->of_reset = vfio_platform_lookup_reset(vdev->compat,
122							&vdev->reset_module);
123	}
124
125	return vdev->of_reset ? 0 : -ENOENT;
126}
127
128static void vfio_platform_put_reset(struct vfio_platform_device *vdev)
129{
130	if (VFIO_PLATFORM_IS_ACPI(vdev))
131		return;
132
133	if (vdev->of_reset)
134		module_put(vdev->reset_module);
135}
136
137static int vfio_platform_regions_init(struct vfio_platform_device *vdev)
138{
139	int cnt = 0, i;
140
141	while (vdev->get_resource(vdev, cnt))
142		cnt++;
143
144	vdev->regions = kcalloc(cnt, sizeof(struct vfio_platform_region),
145				GFP_KERNEL_ACCOUNT);
146	if (!vdev->regions)
147		return -ENOMEM;
148
149	for (i = 0; i < cnt;  i++) {
150		struct resource *res =
151			vdev->get_resource(vdev, i);
152
 
 
 
153		vdev->regions[i].addr = res->start;
154		vdev->regions[i].size = resource_size(res);
155		vdev->regions[i].flags = 0;
156
157		switch (resource_type(res)) {
158		case IORESOURCE_MEM:
159			vdev->regions[i].type = VFIO_PLATFORM_REGION_TYPE_MMIO;
160			vdev->regions[i].flags |= VFIO_REGION_INFO_FLAG_READ;
161			if (!(res->flags & IORESOURCE_READONLY))
162				vdev->regions[i].flags |=
163					VFIO_REGION_INFO_FLAG_WRITE;
164
165			/*
166			 * Only regions addressed with PAGE granularity may be
167			 * MMAPed securely.
168			 */
169			if (!(vdev->regions[i].addr & ~PAGE_MASK) &&
170					!(vdev->regions[i].size & ~PAGE_MASK))
171				vdev->regions[i].flags |=
172					VFIO_REGION_INFO_FLAG_MMAP;
173
174			break;
175		case IORESOURCE_IO:
176			vdev->regions[i].type = VFIO_PLATFORM_REGION_TYPE_PIO;
177			break;
178		default:
179			goto err;
180		}
181	}
182
183	vdev->num_regions = cnt;
184
185	return 0;
186err:
187	kfree(vdev->regions);
188	return -EINVAL;
189}
190
191static void vfio_platform_regions_cleanup(struct vfio_platform_device *vdev)
192{
193	int i;
194
195	for (i = 0; i < vdev->num_regions; i++)
196		iounmap(vdev->regions[i].ioaddr);
197
198	vdev->num_regions = 0;
199	kfree(vdev->regions);
200}
201
202static int vfio_platform_call_reset(struct vfio_platform_device *vdev,
203				    const char **extra_dbg)
204{
205	if (VFIO_PLATFORM_IS_ACPI(vdev)) {
206		dev_info(vdev->device, "reset\n");
207		return vfio_platform_acpi_call_reset(vdev, extra_dbg);
208	} else if (vdev->of_reset) {
209		dev_info(vdev->device, "reset\n");
210		return vdev->of_reset(vdev);
211	}
212
213	dev_warn(vdev->device, "no reset function found!\n");
214	return -EINVAL;
215}
216
217void vfio_platform_close_device(struct vfio_device *core_vdev)
218{
219	struct vfio_platform_device *vdev =
220		container_of(core_vdev, struct vfio_platform_device, vdev);
221	const char *extra_dbg = NULL;
222	int ret;
223
224	ret = vfio_platform_call_reset(vdev, &extra_dbg);
225	if (WARN_ON(ret && vdev->reset_required)) {
226		dev_warn(
227			vdev->device,
228			"reset driver is required and reset call failed in release (%d) %s\n",
229			ret, extra_dbg ? extra_dbg : "");
 
 
 
 
 
 
 
 
 
230	}
231	pm_runtime_put(vdev->device);
232	vfio_platform_regions_cleanup(vdev);
233	vfio_platform_irq_cleanup(vdev);
234}
235EXPORT_SYMBOL_GPL(vfio_platform_close_device);
236
237int vfio_platform_open_device(struct vfio_device *core_vdev)
238{
239	struct vfio_platform_device *vdev =
240		container_of(core_vdev, struct vfio_platform_device, vdev);
241	const char *extra_dbg = NULL;
242	int ret;
243
244	ret = vfio_platform_regions_init(vdev);
245	if (ret)
246		return ret;
247
248	ret = vfio_platform_irq_init(vdev);
249	if (ret)
250		goto err_irq;
251
252	ret = pm_runtime_get_sync(vdev->device);
253	if (ret < 0)
254		goto err_rst;
255
256	ret = vfio_platform_call_reset(vdev, &extra_dbg);
257	if (ret && vdev->reset_required) {
258		dev_warn(
259			vdev->device,
260			"reset driver is required and reset call failed in open (%d) %s\n",
261			ret, extra_dbg ? extra_dbg : "");
262		goto err_rst;
 
 
 
 
 
 
 
263	}
 
 
 
 
264	return 0;
265
266err_rst:
267	pm_runtime_put(vdev->device);
268	vfio_platform_irq_cleanup(vdev);
269err_irq:
270	vfio_platform_regions_cleanup(vdev);
 
 
271	return ret;
272}
273EXPORT_SYMBOL_GPL(vfio_platform_open_device);
274
275long vfio_platform_ioctl(struct vfio_device *core_vdev,
276			 unsigned int cmd, unsigned long arg)
277{
278	struct vfio_platform_device *vdev =
279		container_of(core_vdev, struct vfio_platform_device, vdev);
280
281	unsigned long minsz;
282
283	if (cmd == VFIO_DEVICE_GET_INFO) {
284		struct vfio_device_info info;
285
286		minsz = offsetofend(struct vfio_device_info, num_irqs);
287
288		if (copy_from_user(&info, (void __user *)arg, minsz))
289			return -EFAULT;
290
291		if (info.argsz < minsz)
292			return -EINVAL;
293
294		if (vfio_platform_has_reset(vdev))
295			vdev->flags |= VFIO_DEVICE_FLAGS_RESET;
296		info.flags = vdev->flags;
297		info.num_regions = vdev->num_regions;
298		info.num_irqs = vdev->num_irqs;
299
300		return copy_to_user((void __user *)arg, &info, minsz) ?
301			-EFAULT : 0;
302
303	} else if (cmd == VFIO_DEVICE_GET_REGION_INFO) {
304		struct vfio_region_info info;
305
306		minsz = offsetofend(struct vfio_region_info, offset);
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 (info.index >= vdev->num_regions)
315			return -EINVAL;
316
317		/* map offset to the physical address  */
318		info.offset = VFIO_PLATFORM_INDEX_TO_OFFSET(info.index);
319		info.size = vdev->regions[info.index].size;
320		info.flags = vdev->regions[info.index].flags;
321
322		return copy_to_user((void __user *)arg, &info, minsz) ?
323			-EFAULT : 0;
324
325	} else if (cmd == VFIO_DEVICE_GET_IRQ_INFO) {
326		struct vfio_irq_info info;
327
328		minsz = offsetofend(struct vfio_irq_info, count);
329
330		if (copy_from_user(&info, (void __user *)arg, minsz))
331			return -EFAULT;
332
333		if (info.argsz < minsz)
334			return -EINVAL;
335
336		if (info.index >= vdev->num_irqs)
337			return -EINVAL;
338
339		info.flags = vdev->irqs[info.index].flags;
340		info.count = vdev->irqs[info.index].count;
341
342		return copy_to_user((void __user *)arg, &info, minsz) ?
343			-EFAULT : 0;
344
345	} else if (cmd == VFIO_DEVICE_SET_IRQS) {
346		struct vfio_irq_set hdr;
347		u8 *data = NULL;
348		int ret = 0;
349		size_t data_size = 0;
350
351		minsz = offsetofend(struct vfio_irq_set, count);
352
353		if (copy_from_user(&hdr, (void __user *)arg, minsz))
354			return -EFAULT;
355
356		ret = vfio_set_irqs_validate_and_prepare(&hdr, vdev->num_irqs,
357						 vdev->num_irqs, &data_size);
358		if (ret)
359			return ret;
360
361		if (data_size) {
362			data = memdup_user((void __user *)(arg + minsz),
363					    data_size);
364			if (IS_ERR(data))
365				return PTR_ERR(data);
366		}
367
368		mutex_lock(&vdev->igate);
369
370		ret = vfio_platform_set_irqs_ioctl(vdev, hdr.flags, hdr.index,
371						   hdr.start, hdr.count, data);
372		mutex_unlock(&vdev->igate);
373		kfree(data);
374
375		return ret;
376
377	} else if (cmd == VFIO_DEVICE_RESET) {
378		return vfio_platform_call_reset(vdev, NULL);
379	}
380
381	return -ENOTTY;
382}
383EXPORT_SYMBOL_GPL(vfio_platform_ioctl);
384
385static ssize_t vfio_platform_read_mmio(struct vfio_platform_region *reg,
386				       char __user *buf, size_t count,
387				       loff_t off)
388{
389	unsigned int done = 0;
390
391	if (!reg->ioaddr) {
392		reg->ioaddr =
393			ioremap(reg->addr, reg->size);
394
395		if (!reg->ioaddr)
396			return -ENOMEM;
397	}
398
399	while (count) {
400		size_t filled;
401
402		if (count >= 4 && !(off % 4)) {
403			u32 val;
404
405			val = ioread32(reg->ioaddr + off);
406			if (copy_to_user(buf, &val, 4))
407				goto err;
408
409			filled = 4;
410		} else if (count >= 2 && !(off % 2)) {
411			u16 val;
412
413			val = ioread16(reg->ioaddr + off);
414			if (copy_to_user(buf, &val, 2))
415				goto err;
416
417			filled = 2;
418		} else {
419			u8 val;
420
421			val = ioread8(reg->ioaddr + off);
422			if (copy_to_user(buf, &val, 1))
423				goto err;
424
425			filled = 1;
426		}
427
428
429		count -= filled;
430		done += filled;
431		off += filled;
432		buf += filled;
433	}
434
435	return done;
436err:
437	return -EFAULT;
438}
439
440ssize_t vfio_platform_read(struct vfio_device *core_vdev,
441			   char __user *buf, size_t count, loff_t *ppos)
442{
443	struct vfio_platform_device *vdev =
444		container_of(core_vdev, struct vfio_platform_device, vdev);
445	unsigned int index = VFIO_PLATFORM_OFFSET_TO_INDEX(*ppos);
446	loff_t off = *ppos & VFIO_PLATFORM_OFFSET_MASK;
447
448	if (index >= vdev->num_regions)
449		return -EINVAL;
450
451	if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_READ))
452		return -EINVAL;
453
454	if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_MMIO)
455		return vfio_platform_read_mmio(&vdev->regions[index],
456							buf, count, off);
457	else if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_PIO)
458		return -EINVAL; /* not implemented */
459
460	return -EINVAL;
461}
462EXPORT_SYMBOL_GPL(vfio_platform_read);
463
464static ssize_t vfio_platform_write_mmio(struct vfio_platform_region *reg,
465					const char __user *buf, size_t count,
466					loff_t off)
467{
468	unsigned int done = 0;
469
470	if (!reg->ioaddr) {
471		reg->ioaddr =
472			ioremap(reg->addr, reg->size);
473
474		if (!reg->ioaddr)
475			return -ENOMEM;
476	}
477
478	while (count) {
479		size_t filled;
480
481		if (count >= 4 && !(off % 4)) {
482			u32 val;
483
484			if (copy_from_user(&val, buf, 4))
485				goto err;
486			iowrite32(val, reg->ioaddr + off);
487
488			filled = 4;
489		} else if (count >= 2 && !(off % 2)) {
490			u16 val;
491
492			if (copy_from_user(&val, buf, 2))
493				goto err;
494			iowrite16(val, reg->ioaddr + off);
495
496			filled = 2;
497		} else {
498			u8 val;
499
500			if (copy_from_user(&val, buf, 1))
501				goto err;
502			iowrite8(val, reg->ioaddr + off);
503
504			filled = 1;
505		}
506
507		count -= filled;
508		done += filled;
509		off += filled;
510		buf += filled;
511	}
512
513	return done;
514err:
515	return -EFAULT;
516}
517
518ssize_t vfio_platform_write(struct vfio_device *core_vdev, const char __user *buf,
519			    size_t count, loff_t *ppos)
520{
521	struct vfio_platform_device *vdev =
522		container_of(core_vdev, struct vfio_platform_device, vdev);
523	unsigned int index = VFIO_PLATFORM_OFFSET_TO_INDEX(*ppos);
524	loff_t off = *ppos & VFIO_PLATFORM_OFFSET_MASK;
525
526	if (index >= vdev->num_regions)
527		return -EINVAL;
528
529	if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_WRITE))
530		return -EINVAL;
531
532	if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_MMIO)
533		return vfio_platform_write_mmio(&vdev->regions[index],
534							buf, count, off);
535	else if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_PIO)
536		return -EINVAL; /* not implemented */
537
538	return -EINVAL;
539}
540EXPORT_SYMBOL_GPL(vfio_platform_write);
541
542static int vfio_platform_mmap_mmio(struct vfio_platform_region region,
543				   struct vm_area_struct *vma)
544{
545	u64 req_len, pgoff, req_start;
546
547	req_len = vma->vm_end - vma->vm_start;
548	pgoff = vma->vm_pgoff &
549		((1U << (VFIO_PLATFORM_OFFSET_SHIFT - PAGE_SHIFT)) - 1);
550	req_start = pgoff << PAGE_SHIFT;
551
552	if (region.size < PAGE_SIZE || req_start + req_len > region.size)
553		return -EINVAL;
554
555	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
556	vma->vm_pgoff = (region.addr >> PAGE_SHIFT) + pgoff;
557
558	return remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
559			       req_len, vma->vm_page_prot);
560}
561
562int vfio_platform_mmap(struct vfio_device *core_vdev, struct vm_area_struct *vma)
563{
564	struct vfio_platform_device *vdev =
565		container_of(core_vdev, struct vfio_platform_device, vdev);
566	unsigned int index;
567
568	index = vma->vm_pgoff >> (VFIO_PLATFORM_OFFSET_SHIFT - PAGE_SHIFT);
569
570	if (vma->vm_end < vma->vm_start)
571		return -EINVAL;
572	if (!(vma->vm_flags & VM_SHARED))
573		return -EINVAL;
574	if (index >= vdev->num_regions)
575		return -EINVAL;
576	if (vma->vm_start & ~PAGE_MASK)
577		return -EINVAL;
578	if (vma->vm_end & ~PAGE_MASK)
579		return -EINVAL;
580
581	if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_MMAP))
582		return -EINVAL;
583
584	if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_READ)
585			&& (vma->vm_flags & VM_READ))
586		return -EINVAL;
587
588	if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_WRITE)
589			&& (vma->vm_flags & VM_WRITE))
590		return -EINVAL;
591
592	vma->vm_private_data = vdev;
593
594	if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_MMIO)
595		return vfio_platform_mmap_mmio(vdev->regions[index], vma);
596
597	else if (vdev->regions[index].type & VFIO_PLATFORM_REGION_TYPE_PIO)
598		return -EINVAL; /* not implemented */
599
600	return -EINVAL;
601}
602EXPORT_SYMBOL_GPL(vfio_platform_mmap);
 
 
 
 
 
 
 
 
 
603
604static int vfio_platform_of_probe(struct vfio_platform_device *vdev,
605			   struct device *dev)
606{
607	int ret;
608
609	ret = device_property_read_string(dev, "compatible",
610					  &vdev->compat);
611	if (ret)
612		dev_err(dev, "Cannot retrieve compat for %s\n", vdev->name);
613
614	return ret;
615}
616
617/*
618 * There can be two kernel build combinations. One build where
619 * ACPI is not selected in Kconfig and another one with the ACPI Kconfig.
620 *
621 * In the first case, vfio_platform_acpi_probe will return since
622 * acpi_disabled is 1. DT user will not see any kind of messages from
623 * ACPI.
624 *
625 * In the second case, both DT and ACPI is compiled in but the system is
626 * booting with any of these combinations.
627 *
628 * If the firmware is DT type, then acpi_disabled is 1. The ACPI probe routine
629 * terminates immediately without any messages.
630 *
631 * If the firmware is ACPI type, then acpi_disabled is 0. All other checks are
632 * valid checks. We cannot claim that this system is DT.
633 */
634int vfio_platform_init_common(struct vfio_platform_device *vdev)
 
635{
 
636	int ret;
637	struct device *dev = vdev->vdev.dev;
 
638
639	ret = vfio_platform_acpi_probe(vdev, dev);
640	if (ret)
641		ret = vfio_platform_of_probe(vdev, dev);
642
643	if (ret)
644		return ret;
645
646	vdev->device = dev;
647	mutex_init(&vdev->igate);
648
649	ret = vfio_platform_get_reset(vdev);
650	if (ret && vdev->reset_required) {
651		dev_err(dev, "No reset function found for device %s\n",
652			vdev->name);
653		return ret;
654	}
655
 
 
 
 
 
 
 
 
 
 
 
 
 
 
656	return 0;
 
 
 
 
 
 
657}
658EXPORT_SYMBOL_GPL(vfio_platform_init_common);
659
660void vfio_platform_release_common(struct vfio_platform_device *vdev)
661{
 
 
 
662	vfio_platform_put_reset(vdev);
 
663}
664EXPORT_SYMBOL_GPL(vfio_platform_release_common);
665
666void __vfio_platform_register_reset(struct vfio_platform_reset_node *node)
667{
668	mutex_lock(&driver_lock);
669	list_add(&node->link, &reset_list);
670	mutex_unlock(&driver_lock);
671}
672EXPORT_SYMBOL_GPL(__vfio_platform_register_reset);
673
674void vfio_platform_unregister_reset(const char *compat,
675				    vfio_platform_reset_fn_t fn)
676{
677	struct vfio_platform_reset_node *iter, *temp;
678
679	mutex_lock(&driver_lock);
680	list_for_each_entry_safe(iter, temp, &reset_list, link) {
681		if (!strcmp(iter->compat, compat) && (iter->of_reset == fn)) {
682			list_del(&iter->link);
683			break;
684		}
685	}
686
687	mutex_unlock(&driver_lock);
688
689}
690EXPORT_SYMBOL_GPL(vfio_platform_unregister_reset);
691
692MODULE_VERSION(DRIVER_VERSION);
693MODULE_LICENSE("GPL v2");
694MODULE_AUTHOR(DRIVER_AUTHOR);
695MODULE_DESCRIPTION(DRIVER_DESC);
v5.14.15
  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
 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			 * 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;
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		/* map offset to the physical address  */
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; /* not implemented */
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; /* not implemented */
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; /* not implemented */
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/*
641 * There can be two kernel build combinations. One build where
642 * ACPI is not selected in Kconfig and another one with the ACPI Kconfig.
643 *
644 * In the first case, vfio_platform_acpi_probe will return since
645 * acpi_disabled is 1. DT user will not see any kind of messages from
646 * ACPI.
647 *
648 * In the second case, both DT and ACPI is compiled in but the system is
649 * booting with any of these combinations.
650 *
651 * If the firmware is DT type, then acpi_disabled is 1. The ACPI probe routine
652 * terminates immediately without any messages.
653 *
654 * If the firmware is ACPI type, then acpi_disabled is 0. All other checks are
655 * valid checks. We cannot claim that this system is DT.
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);