xref: /linux/drivers/vfio/cdx/main.c (revision 249ebf3f65f8530beb2cbfb91bff1d83ba88d23c)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) 2022-2023, Advanced Micro Devices, Inc.
4  */
5 
6 #include <linux/vfio.h>
7 #include <linux/cdx/cdx_bus.h>
8 
9 #include "private.h"
10 
11 static int vfio_cdx_open_device(struct vfio_device *core_vdev)
12 {
13 	struct vfio_cdx_device *vdev =
14 		container_of(core_vdev, struct vfio_cdx_device, vdev);
15 	struct cdx_device *cdx_dev = to_cdx_device(core_vdev->dev);
16 	int count = cdx_dev->res_count;
17 	int i, ret;
18 
19 	vdev->regions = kcalloc(count, sizeof(struct vfio_cdx_region),
20 				GFP_KERNEL_ACCOUNT);
21 	if (!vdev->regions)
22 		return -ENOMEM;
23 
24 	for (i = 0; i < count; i++) {
25 		struct resource *res = &cdx_dev->res[i];
26 
27 		vdev->regions[i].addr = res->start;
28 		vdev->regions[i].size = resource_size(res);
29 		vdev->regions[i].type = res->flags;
30 		/*
31 		 * Only regions addressed with PAGE granularity may be
32 		 * MMAP'ed securely.
33 		 */
34 		if (!(vdev->regions[i].addr & ~PAGE_MASK) &&
35 		    !(vdev->regions[i].size & ~PAGE_MASK))
36 			vdev->regions[i].flags |=
37 					VFIO_REGION_INFO_FLAG_MMAP;
38 		vdev->regions[i].flags |= VFIO_REGION_INFO_FLAG_READ;
39 		if (!(cdx_dev->res[i].flags & IORESOURCE_READONLY))
40 			vdev->regions[i].flags |= VFIO_REGION_INFO_FLAG_WRITE;
41 	}
42 	ret = cdx_dev_reset(core_vdev->dev);
43 	if (ret) {
44 		kfree(vdev->regions);
45 		vdev->regions = NULL;
46 		return ret;
47 	}
48 	ret = cdx_clear_master(cdx_dev);
49 	if (ret)
50 		vdev->flags &= ~BME_SUPPORT;
51 	else
52 		vdev->flags |= BME_SUPPORT;
53 
54 	return 0;
55 }
56 
57 static void vfio_cdx_close_device(struct vfio_device *core_vdev)
58 {
59 	struct vfio_cdx_device *vdev =
60 		container_of(core_vdev, struct vfio_cdx_device, vdev);
61 
62 	kfree(vdev->regions);
63 	cdx_dev_reset(core_vdev->dev);
64 	vfio_cdx_irqs_cleanup(vdev);
65 }
66 
67 static int vfio_cdx_bm_ctrl(struct vfio_device *core_vdev, u32 flags,
68 			    void __user *arg, size_t argsz)
69 {
70 	size_t minsz =
71 		offsetofend(struct vfio_device_feature_bus_master, op);
72 	struct vfio_cdx_device *vdev =
73 		container_of(core_vdev, struct vfio_cdx_device, vdev);
74 	struct cdx_device *cdx_dev = to_cdx_device(core_vdev->dev);
75 	struct vfio_device_feature_bus_master ops;
76 	int ret;
77 
78 	if (!(vdev->flags & BME_SUPPORT))
79 		return -ENOTTY;
80 
81 	ret = vfio_check_feature(flags, argsz, VFIO_DEVICE_FEATURE_SET,
82 				 sizeof(ops));
83 	if (ret != 1)
84 		return ret;
85 
86 	if (copy_from_user(&ops, arg, minsz))
87 		return -EFAULT;
88 
89 	switch (ops.op) {
90 	case VFIO_DEVICE_FEATURE_CLEAR_MASTER:
91 		return cdx_clear_master(cdx_dev);
92 	case VFIO_DEVICE_FEATURE_SET_MASTER:
93 		return cdx_set_master(cdx_dev);
94 	default:
95 		return -EINVAL;
96 	}
97 }
98 
99 static int vfio_cdx_ioctl_feature(struct vfio_device *device, u32 flags,
100 				  void __user *arg, size_t argsz)
101 {
102 	switch (flags & VFIO_DEVICE_FEATURE_MASK) {
103 	case VFIO_DEVICE_FEATURE_BUS_MASTER:
104 		return vfio_cdx_bm_ctrl(device, flags, arg, argsz);
105 	default:
106 		return -ENOTTY;
107 	}
108 }
109 
110 static int vfio_cdx_ioctl_get_info(struct vfio_cdx_device *vdev,
111 				   struct vfio_device_info __user *arg)
112 {
113 	unsigned long minsz = offsetofend(struct vfio_device_info, num_irqs);
114 	struct cdx_device *cdx_dev = to_cdx_device(vdev->vdev.dev);
115 	struct vfio_device_info info;
116 
117 	if (copy_from_user(&info, arg, minsz))
118 		return -EFAULT;
119 
120 	if (info.argsz < minsz)
121 		return -EINVAL;
122 
123 	info.flags = VFIO_DEVICE_FLAGS_CDX;
124 	info.flags |= VFIO_DEVICE_FLAGS_RESET;
125 
126 	info.num_regions = cdx_dev->res_count;
127 	info.num_irqs = cdx_dev->num_msi ? 1 : 0;
128 
129 	return copy_to_user(arg, &info, minsz) ? -EFAULT : 0;
130 }
131 
132 static int vfio_cdx_ioctl_get_region_info(struct vfio_cdx_device *vdev,
133 					  struct vfio_region_info __user *arg)
134 {
135 	unsigned long minsz = offsetofend(struct vfio_region_info, offset);
136 	struct cdx_device *cdx_dev = to_cdx_device(vdev->vdev.dev);
137 	struct vfio_region_info info;
138 
139 	if (copy_from_user(&info, arg, minsz))
140 		return -EFAULT;
141 
142 	if (info.argsz < minsz)
143 		return -EINVAL;
144 
145 	if (info.index >= cdx_dev->res_count)
146 		return -EINVAL;
147 
148 	/* map offset to the physical address */
149 	info.offset = vfio_cdx_index_to_offset(info.index);
150 	info.size = vdev->regions[info.index].size;
151 	info.flags = vdev->regions[info.index].flags;
152 
153 	return copy_to_user(arg, &info, minsz) ? -EFAULT : 0;
154 }
155 
156 static int vfio_cdx_ioctl_get_irq_info(struct vfio_cdx_device *vdev,
157 				       struct vfio_irq_info __user *arg)
158 {
159 	unsigned long minsz = offsetofend(struct vfio_irq_info, count);
160 	struct cdx_device *cdx_dev = to_cdx_device(vdev->vdev.dev);
161 	struct vfio_irq_info info;
162 
163 	if (copy_from_user(&info, arg, minsz))
164 		return -EFAULT;
165 
166 	if (info.argsz < minsz)
167 		return -EINVAL;
168 
169 	if (info.index >= 1)
170 		return -EINVAL;
171 
172 	if (!cdx_dev->num_msi)
173 		return -EINVAL;
174 
175 	info.flags = VFIO_IRQ_INFO_EVENTFD | VFIO_IRQ_INFO_NORESIZE;
176 	info.count = cdx_dev->num_msi;
177 
178 	return copy_to_user(arg, &info, minsz) ? -EFAULT : 0;
179 }
180 
181 static int vfio_cdx_ioctl_set_irqs(struct vfio_cdx_device *vdev,
182 				   struct vfio_irq_set __user *arg)
183 {
184 	unsigned long minsz = offsetofend(struct vfio_irq_set, count);
185 	struct cdx_device *cdx_dev = to_cdx_device(vdev->vdev.dev);
186 	struct vfio_irq_set hdr;
187 	size_t data_size = 0;
188 	u8 *data = NULL;
189 	int ret = 0;
190 
191 	if (copy_from_user(&hdr, arg, minsz))
192 		return -EFAULT;
193 
194 	ret = vfio_set_irqs_validate_and_prepare(&hdr, cdx_dev->num_msi,
195 						 1, &data_size);
196 	if (ret)
197 		return ret;
198 
199 	if (data_size) {
200 		data = memdup_user(arg->data, data_size);
201 		if (IS_ERR(data))
202 			return PTR_ERR(data);
203 	}
204 
205 	ret = vfio_cdx_set_irqs_ioctl(vdev, hdr.flags, hdr.index,
206 				      hdr.start, hdr.count, data);
207 	kfree(data);
208 
209 	return ret;
210 }
211 
212 static long vfio_cdx_ioctl(struct vfio_device *core_vdev,
213 			   unsigned int cmd, unsigned long arg)
214 {
215 	struct vfio_cdx_device *vdev =
216 		container_of(core_vdev, struct vfio_cdx_device, vdev);
217 	void __user *uarg = (void __user *)arg;
218 
219 	switch (cmd) {
220 	case VFIO_DEVICE_GET_INFO:
221 		return vfio_cdx_ioctl_get_info(vdev, uarg);
222 	case VFIO_DEVICE_GET_REGION_INFO:
223 		return vfio_cdx_ioctl_get_region_info(vdev, uarg);
224 	case VFIO_DEVICE_GET_IRQ_INFO:
225 		return vfio_cdx_ioctl_get_irq_info(vdev, uarg);
226 	case VFIO_DEVICE_SET_IRQS:
227 		return vfio_cdx_ioctl_set_irqs(vdev, uarg);
228 	case VFIO_DEVICE_RESET:
229 		return cdx_dev_reset(core_vdev->dev);
230 	default:
231 		return -ENOTTY;
232 	}
233 }
234 
235 static int vfio_cdx_mmap_mmio(struct vfio_cdx_region region,
236 			      struct vm_area_struct *vma)
237 {
238 	u64 size = vma->vm_end - vma->vm_start;
239 	u64 pgoff, base;
240 
241 	pgoff = vma->vm_pgoff &
242 		((1U << (VFIO_CDX_OFFSET_SHIFT - PAGE_SHIFT)) - 1);
243 	base = pgoff << PAGE_SHIFT;
244 
245 	if (base + size > region.size)
246 		return -EINVAL;
247 
248 	vma->vm_pgoff = (region.addr >> PAGE_SHIFT) + pgoff;
249 	vma->vm_page_prot = pgprot_device(vma->vm_page_prot);
250 
251 	return io_remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
252 				  size, vma->vm_page_prot);
253 }
254 
255 static int vfio_cdx_mmap(struct vfio_device *core_vdev,
256 			 struct vm_area_struct *vma)
257 {
258 	struct vfio_cdx_device *vdev =
259 		container_of(core_vdev, struct vfio_cdx_device, vdev);
260 	struct cdx_device *cdx_dev = to_cdx_device(core_vdev->dev);
261 	unsigned int index;
262 
263 	index = vma->vm_pgoff >> (VFIO_CDX_OFFSET_SHIFT - PAGE_SHIFT);
264 
265 	if (index >= cdx_dev->res_count)
266 		return -EINVAL;
267 
268 	if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_MMAP))
269 		return -EINVAL;
270 
271 	if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_READ) &&
272 	    (vma->vm_flags & VM_READ))
273 		return -EPERM;
274 
275 	if (!(vdev->regions[index].flags & VFIO_REGION_INFO_FLAG_WRITE) &&
276 	    (vma->vm_flags & VM_WRITE))
277 		return -EPERM;
278 
279 	return vfio_cdx_mmap_mmio(vdev->regions[index], vma);
280 }
281 
282 static const struct vfio_device_ops vfio_cdx_ops = {
283 	.name		= "vfio-cdx",
284 	.open_device	= vfio_cdx_open_device,
285 	.close_device	= vfio_cdx_close_device,
286 	.ioctl		= vfio_cdx_ioctl,
287 	.device_feature = vfio_cdx_ioctl_feature,
288 	.mmap		= vfio_cdx_mmap,
289 	.bind_iommufd	= vfio_iommufd_physical_bind,
290 	.unbind_iommufd	= vfio_iommufd_physical_unbind,
291 	.attach_ioas	= vfio_iommufd_physical_attach_ioas,
292 };
293 
294 static int vfio_cdx_probe(struct cdx_device *cdx_dev)
295 {
296 	struct vfio_cdx_device *vdev;
297 	struct device *dev = &cdx_dev->dev;
298 	int ret;
299 
300 	vdev = vfio_alloc_device(vfio_cdx_device, vdev, dev,
301 				 &vfio_cdx_ops);
302 	if (IS_ERR(vdev))
303 		return PTR_ERR(vdev);
304 
305 	ret = vfio_register_group_dev(&vdev->vdev);
306 	if (ret)
307 		goto out_uninit;
308 
309 	dev_set_drvdata(dev, vdev);
310 	return 0;
311 
312 out_uninit:
313 	vfio_put_device(&vdev->vdev);
314 	return ret;
315 }
316 
317 static int vfio_cdx_remove(struct cdx_device *cdx_dev)
318 {
319 	struct device *dev = &cdx_dev->dev;
320 	struct vfio_cdx_device *vdev = dev_get_drvdata(dev);
321 
322 	vfio_unregister_group_dev(&vdev->vdev);
323 	vfio_put_device(&vdev->vdev);
324 
325 	return 0;
326 }
327 
328 static const struct cdx_device_id vfio_cdx_table[] = {
329 	{ CDX_DEVICE_DRIVER_OVERRIDE(CDX_ANY_ID, CDX_ANY_ID,
330 				     CDX_ID_F_VFIO_DRIVER_OVERRIDE) }, /* match all by default */
331 	{}
332 };
333 
334 MODULE_DEVICE_TABLE(cdx, vfio_cdx_table);
335 
336 static struct cdx_driver vfio_cdx_driver = {
337 	.probe		= vfio_cdx_probe,
338 	.remove		= vfio_cdx_remove,
339 	.match_id_table	= vfio_cdx_table,
340 	.driver	= {
341 		.name	= "vfio-cdx",
342 	},
343 	.driver_managed_dma = true,
344 };
345 
346 module_driver(vfio_cdx_driver, cdx_driver_register, cdx_driver_unregister);
347 
348 MODULE_LICENSE("GPL");
349 MODULE_DESCRIPTION("VFIO for CDX devices - User Level meta-driver");
350 MODULE_IMPORT_NS(CDX_BUS);
351