1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Mediated virtual PCI display host device driver
4 *
5 * See mdpy-defs.h for device specs
6 *
7 * (c) Gerd Hoffmann <kraxel@redhat.com>
8 *
9 * based on mtty driver which is:
10 * Copyright (c) 2016, NVIDIA CORPORATION. All rights reserved.
11 * Author: Neo Jia <cjia@nvidia.com>
12 * Kirti Wankhede <kwankhede@nvidia.com>
13 *
14 * This program is free software; you can redistribute it and/or modify
15 * it under the terms of the GNU General Public License version 2 as
16 * published by the Free Software Foundation.
17 */
18 #include <linux/init.h>
19 #include <linux/module.h>
20 #include <linux/device.h>
21 #include <linux/kernel.h>
22 #include <linux/slab.h>
23 #include <linux/vmalloc.h>
24 #include <linux/cdev.h>
25 #include <linux/vfio.h>
26 #include <linux/iommu.h>
27 #include <linux/sysfs.h>
28 #include <linux/mdev.h>
29 #include <linux/pci.h>
30 #include <drm/drm_fourcc.h>
31 #include "mdpy-defs.h"
32
33 #define MDPY_NAME "mdpy"
34 #define MDPY_CLASS_NAME "mdpy"
35
36 #define MDPY_CONFIG_SPACE_SIZE 0xff
37 #define MDPY_MEMORY_BAR_OFFSET PAGE_SIZE
38 #define MDPY_DISPLAY_REGION 16
39
40 #define STORE_LE16(addr, val) (*(u16 *)addr = val)
41 #define STORE_LE32(addr, val) (*(u32 *)addr = val)
42
43
44 MODULE_LICENSE("GPL v2");
45
46 static int max_devices = 4;
47 module_param_named(count, max_devices, int, 0444);
48 MODULE_PARM_DESC(count, "number of " MDPY_NAME " devices");
49
50
51 #define MDPY_TYPE_1 "vga"
52 #define MDPY_TYPE_2 "xga"
53 #define MDPY_TYPE_3 "hd"
54
55 static const struct mdpy_type {
56 const char *name;
57 u32 format;
58 u32 bytepp;
59 u32 width;
60 u32 height;
61 } mdpy_types[] = {
62 {
63 .name = MDPY_CLASS_NAME "-" MDPY_TYPE_1,
64 .format = DRM_FORMAT_XRGB8888,
65 .bytepp = 4,
66 .width = 640,
67 .height = 480,
68 }, {
69 .name = MDPY_CLASS_NAME "-" MDPY_TYPE_2,
70 .format = DRM_FORMAT_XRGB8888,
71 .bytepp = 4,
72 .width = 1024,
73 .height = 768,
74 }, {
75 .name = MDPY_CLASS_NAME "-" MDPY_TYPE_3,
76 .format = DRM_FORMAT_XRGB8888,
77 .bytepp = 4,
78 .width = 1920,
79 .height = 1080,
80 },
81 };
82
83 static dev_t mdpy_devt;
84 static struct class *mdpy_class;
85 static struct cdev mdpy_cdev;
86 static struct device mdpy_dev;
87 static u32 mdpy_count;
88 static const struct vfio_device_ops mdpy_dev_ops;
89
90 /* State of each mdev device */
91 struct mdev_state {
92 struct vfio_device vdev;
93 u8 *vconfig;
94 u32 bar_mask;
95 struct mutex ops_lock;
96 struct mdev_device *mdev;
97 struct vfio_device_info dev_info;
98
99 const struct mdpy_type *type;
100 u32 memsize;
101 void *memblk;
102 };
103
mdpy_create_config_space(struct mdev_state * mdev_state)104 static void mdpy_create_config_space(struct mdev_state *mdev_state)
105 {
106 STORE_LE16((u16 *) &mdev_state->vconfig[PCI_VENDOR_ID],
107 MDPY_PCI_VENDOR_ID);
108 STORE_LE16((u16 *) &mdev_state->vconfig[PCI_DEVICE_ID],
109 MDPY_PCI_DEVICE_ID);
110 STORE_LE16((u16 *) &mdev_state->vconfig[PCI_SUBSYSTEM_VENDOR_ID],
111 MDPY_PCI_SUBVENDOR_ID);
112 STORE_LE16((u16 *) &mdev_state->vconfig[PCI_SUBSYSTEM_ID],
113 MDPY_PCI_SUBDEVICE_ID);
114
115 STORE_LE16((u16 *) &mdev_state->vconfig[PCI_COMMAND],
116 PCI_COMMAND_IO | PCI_COMMAND_MEMORY);
117 STORE_LE16((u16 *) &mdev_state->vconfig[PCI_STATUS],
118 PCI_STATUS_CAP_LIST);
119 STORE_LE16((u16 *) &mdev_state->vconfig[PCI_CLASS_DEVICE],
120 PCI_CLASS_DISPLAY_OTHER);
121 mdev_state->vconfig[PCI_CLASS_REVISION] = 0x01;
122
123 STORE_LE32((u32 *) &mdev_state->vconfig[PCI_BASE_ADDRESS_0],
124 PCI_BASE_ADDRESS_SPACE_MEMORY |
125 PCI_BASE_ADDRESS_MEM_TYPE_32 |
126 PCI_BASE_ADDRESS_MEM_PREFETCH);
127 mdev_state->bar_mask = ~(mdev_state->memsize) + 1;
128
129 /* vendor specific capability for the config registers */
130 mdev_state->vconfig[PCI_CAPABILITY_LIST] = MDPY_VENDORCAP_OFFSET;
131 mdev_state->vconfig[MDPY_VENDORCAP_OFFSET + 0] = 0x09; /* vendor cap */
132 mdev_state->vconfig[MDPY_VENDORCAP_OFFSET + 1] = 0x00; /* next ptr */
133 mdev_state->vconfig[MDPY_VENDORCAP_OFFSET + 2] = MDPY_VENDORCAP_SIZE;
134 STORE_LE32((u32 *) &mdev_state->vconfig[MDPY_FORMAT_OFFSET],
135 mdev_state->type->format);
136 STORE_LE32((u32 *) &mdev_state->vconfig[MDPY_WIDTH_OFFSET],
137 mdev_state->type->width);
138 STORE_LE32((u32 *) &mdev_state->vconfig[MDPY_HEIGHT_OFFSET],
139 mdev_state->type->height);
140 }
141
handle_pci_cfg_write(struct mdev_state * mdev_state,u16 offset,char * buf,u32 count)142 static void handle_pci_cfg_write(struct mdev_state *mdev_state, u16 offset,
143 char *buf, u32 count)
144 {
145 struct device *dev = mdev_dev(mdev_state->mdev);
146 u32 cfg_addr;
147
148 switch (offset) {
149 case PCI_BASE_ADDRESS_0:
150 cfg_addr = *(u32 *)buf;
151
152 if (cfg_addr == 0xffffffff) {
153 cfg_addr = (cfg_addr & mdev_state->bar_mask);
154 } else {
155 cfg_addr &= PCI_BASE_ADDRESS_MEM_MASK;
156 if (cfg_addr)
157 dev_info(dev, "BAR0 @ 0x%x\n", cfg_addr);
158 }
159
160 cfg_addr |= (mdev_state->vconfig[offset] &
161 ~PCI_BASE_ADDRESS_MEM_MASK);
162 STORE_LE32(&mdev_state->vconfig[offset], cfg_addr);
163 break;
164 }
165 }
166
mdev_access(struct mdev_state * mdev_state,char * buf,size_t count,loff_t pos,bool is_write)167 static ssize_t mdev_access(struct mdev_state *mdev_state, char *buf,
168 size_t count, loff_t pos, bool is_write)
169 {
170 int ret = 0;
171
172 mutex_lock(&mdev_state->ops_lock);
173
174 if (pos < MDPY_CONFIG_SPACE_SIZE) {
175 if (is_write)
176 handle_pci_cfg_write(mdev_state, pos, buf, count);
177 else
178 memcpy(buf, (mdev_state->vconfig + pos), count);
179
180 } else if ((pos >= MDPY_MEMORY_BAR_OFFSET) &&
181 (pos + count <=
182 MDPY_MEMORY_BAR_OFFSET + mdev_state->memsize)) {
183 pos -= MDPY_MEMORY_BAR_OFFSET;
184 if (is_write)
185 memcpy(mdev_state->memblk, buf, count);
186 else
187 memcpy(buf, mdev_state->memblk, count);
188
189 } else {
190 dev_info(mdev_state->vdev.dev,
191 "%s: %s @0x%llx (unhandled)\n", __func__,
192 is_write ? "WR" : "RD", pos);
193 ret = -1;
194 goto accessfailed;
195 }
196
197 ret = count;
198
199
200 accessfailed:
201 mutex_unlock(&mdev_state->ops_lock);
202
203 return ret;
204 }
205
mdpy_reset(struct mdev_state * mdev_state)206 static int mdpy_reset(struct mdev_state *mdev_state)
207 {
208 u32 stride, i;
209
210 /* initialize with gray gradient */
211 stride = mdev_state->type->width * mdev_state->type->bytepp;
212 for (i = 0; i < mdev_state->type->height; i++)
213 memset(mdev_state->memblk + i * stride,
214 i * 255 / mdev_state->type->height,
215 stride);
216 return 0;
217 }
218
mdpy_probe(struct mdev_device * mdev)219 static int mdpy_probe(struct mdev_device *mdev)
220 {
221 const struct mdpy_type *type =
222 &mdpy_types[mdev_get_type_group_id(mdev)];
223 struct device *dev = mdev_dev(mdev);
224 struct mdev_state *mdev_state;
225 u32 fbsize;
226 int ret;
227
228 if (mdpy_count >= max_devices)
229 return -ENOMEM;
230
231 mdev_state = kzalloc(sizeof(struct mdev_state), GFP_KERNEL);
232 if (mdev_state == NULL)
233 return -ENOMEM;
234 vfio_init_group_dev(&mdev_state->vdev, &mdev->dev, &mdpy_dev_ops);
235
236 mdev_state->vconfig = kzalloc(MDPY_CONFIG_SPACE_SIZE, GFP_KERNEL);
237 if (mdev_state->vconfig == NULL) {
238 ret = -ENOMEM;
239 goto err_state;
240 }
241
242 fbsize = roundup_pow_of_two(type->width * type->height * type->bytepp);
243
244 mdev_state->memblk = vmalloc_user(fbsize);
245 if (!mdev_state->memblk) {
246 ret = -ENOMEM;
247 goto err_vconfig;
248 }
249 dev_info(dev, "%s: %s (%dx%d)\n", __func__, type->name, type->width,
250 type->height);
251
252 mutex_init(&mdev_state->ops_lock);
253 mdev_state->mdev = mdev;
254 mdev_state->type = type;
255 mdev_state->memsize = fbsize;
256 mdpy_create_config_space(mdev_state);
257 mdpy_reset(mdev_state);
258
259 mdpy_count++;
260
261 ret = vfio_register_group_dev(&mdev_state->vdev);
262 if (ret)
263 goto err_mem;
264 dev_set_drvdata(&mdev->dev, mdev_state);
265 return 0;
266 err_mem:
267 vfree(mdev_state->memblk);
268 err_vconfig:
269 kfree(mdev_state->vconfig);
270 err_state:
271 vfio_uninit_group_dev(&mdev_state->vdev);
272 kfree(mdev_state);
273 return ret;
274 }
275
mdpy_remove(struct mdev_device * mdev)276 static void mdpy_remove(struct mdev_device *mdev)
277 {
278 struct mdev_state *mdev_state = dev_get_drvdata(&mdev->dev);
279
280 dev_info(&mdev->dev, "%s\n", __func__);
281
282 vfio_unregister_group_dev(&mdev_state->vdev);
283 vfree(mdev_state->memblk);
284 kfree(mdev_state->vconfig);
285 vfio_uninit_group_dev(&mdev_state->vdev);
286 kfree(mdev_state);
287
288 mdpy_count--;
289 }
290
mdpy_read(struct vfio_device * vdev,char __user * buf,size_t count,loff_t * ppos)291 static ssize_t mdpy_read(struct vfio_device *vdev, char __user *buf,
292 size_t count, loff_t *ppos)
293 {
294 struct mdev_state *mdev_state =
295 container_of(vdev, struct mdev_state, vdev);
296 unsigned int done = 0;
297 int ret;
298
299 while (count) {
300 size_t filled;
301
302 if (count >= 4 && !(*ppos % 4)) {
303 u32 val;
304
305 ret = mdev_access(mdev_state, (char *)&val, sizeof(val),
306 *ppos, false);
307 if (ret <= 0)
308 goto read_err;
309
310 if (copy_to_user(buf, &val, sizeof(val)))
311 goto read_err;
312
313 filled = 4;
314 } else if (count >= 2 && !(*ppos % 2)) {
315 u16 val;
316
317 ret = mdev_access(mdev_state, (char *)&val, sizeof(val),
318 *ppos, false);
319 if (ret <= 0)
320 goto read_err;
321
322 if (copy_to_user(buf, &val, sizeof(val)))
323 goto read_err;
324
325 filled = 2;
326 } else {
327 u8 val;
328
329 ret = mdev_access(mdev_state, (char *)&val, sizeof(val),
330 *ppos, false);
331 if (ret <= 0)
332 goto read_err;
333
334 if (copy_to_user(buf, &val, sizeof(val)))
335 goto read_err;
336
337 filled = 1;
338 }
339
340 count -= filled;
341 done += filled;
342 *ppos += filled;
343 buf += filled;
344 }
345
346 return done;
347
348 read_err:
349 return -EFAULT;
350 }
351
mdpy_write(struct vfio_device * vdev,const char __user * buf,size_t count,loff_t * ppos)352 static ssize_t mdpy_write(struct vfio_device *vdev, const char __user *buf,
353 size_t count, loff_t *ppos)
354 {
355 struct mdev_state *mdev_state =
356 container_of(vdev, struct mdev_state, vdev);
357 unsigned int done = 0;
358 int ret;
359
360 while (count) {
361 size_t filled;
362
363 if (count >= 4 && !(*ppos % 4)) {
364 u32 val;
365
366 if (copy_from_user(&val, buf, sizeof(val)))
367 goto write_err;
368
369 ret = mdev_access(mdev_state, (char *)&val, sizeof(val),
370 *ppos, true);
371 if (ret <= 0)
372 goto write_err;
373
374 filled = 4;
375 } else if (count >= 2 && !(*ppos % 2)) {
376 u16 val;
377
378 if (copy_from_user(&val, buf, sizeof(val)))
379 goto write_err;
380
381 ret = mdev_access(mdev_state, (char *)&val, sizeof(val),
382 *ppos, true);
383 if (ret <= 0)
384 goto write_err;
385
386 filled = 2;
387 } else {
388 u8 val;
389
390 if (copy_from_user(&val, buf, sizeof(val)))
391 goto write_err;
392
393 ret = mdev_access(mdev_state, (char *)&val, sizeof(val),
394 *ppos, true);
395 if (ret <= 0)
396 goto write_err;
397
398 filled = 1;
399 }
400 count -= filled;
401 done += filled;
402 *ppos += filled;
403 buf += filled;
404 }
405
406 return done;
407 write_err:
408 return -EFAULT;
409 }
410
mdpy_mmap(struct vfio_device * vdev,struct vm_area_struct * vma)411 static int mdpy_mmap(struct vfio_device *vdev, struct vm_area_struct *vma)
412 {
413 struct mdev_state *mdev_state =
414 container_of(vdev, struct mdev_state, vdev);
415
416 if (vma->vm_pgoff != MDPY_MEMORY_BAR_OFFSET >> PAGE_SHIFT)
417 return -EINVAL;
418 if (vma->vm_end < vma->vm_start)
419 return -EINVAL;
420 if (vma->vm_end - vma->vm_start > mdev_state->memsize)
421 return -EINVAL;
422 if ((vma->vm_flags & VM_SHARED) == 0)
423 return -EINVAL;
424
425 return remap_vmalloc_range(vma, mdev_state->memblk, 0);
426 }
427
mdpy_get_region_info(struct mdev_state * mdev_state,struct vfio_region_info * region_info,u16 * cap_type_id,void ** cap_type)428 static int mdpy_get_region_info(struct mdev_state *mdev_state,
429 struct vfio_region_info *region_info,
430 u16 *cap_type_id, void **cap_type)
431 {
432 if (region_info->index >= VFIO_PCI_NUM_REGIONS &&
433 region_info->index != MDPY_DISPLAY_REGION)
434 return -EINVAL;
435
436 switch (region_info->index) {
437 case VFIO_PCI_CONFIG_REGION_INDEX:
438 region_info->offset = 0;
439 region_info->size = MDPY_CONFIG_SPACE_SIZE;
440 region_info->flags = (VFIO_REGION_INFO_FLAG_READ |
441 VFIO_REGION_INFO_FLAG_WRITE);
442 break;
443 case VFIO_PCI_BAR0_REGION_INDEX:
444 case MDPY_DISPLAY_REGION:
445 region_info->offset = MDPY_MEMORY_BAR_OFFSET;
446 region_info->size = mdev_state->memsize;
447 region_info->flags = (VFIO_REGION_INFO_FLAG_READ |
448 VFIO_REGION_INFO_FLAG_WRITE |
449 VFIO_REGION_INFO_FLAG_MMAP);
450 break;
451 default:
452 region_info->size = 0;
453 region_info->offset = 0;
454 region_info->flags = 0;
455 }
456
457 return 0;
458 }
459
mdpy_get_irq_info(struct vfio_irq_info * irq_info)460 static int mdpy_get_irq_info(struct vfio_irq_info *irq_info)
461 {
462 irq_info->count = 0;
463 return 0;
464 }
465
mdpy_get_device_info(struct vfio_device_info * dev_info)466 static int mdpy_get_device_info(struct vfio_device_info *dev_info)
467 {
468 dev_info->flags = VFIO_DEVICE_FLAGS_PCI;
469 dev_info->num_regions = VFIO_PCI_NUM_REGIONS;
470 dev_info->num_irqs = VFIO_PCI_NUM_IRQS;
471 return 0;
472 }
473
mdpy_query_gfx_plane(struct mdev_state * mdev_state,struct vfio_device_gfx_plane_info * plane)474 static int mdpy_query_gfx_plane(struct mdev_state *mdev_state,
475 struct vfio_device_gfx_plane_info *plane)
476 {
477 if (plane->flags & VFIO_GFX_PLANE_TYPE_PROBE) {
478 if (plane->flags == (VFIO_GFX_PLANE_TYPE_PROBE |
479 VFIO_GFX_PLANE_TYPE_REGION))
480 return 0;
481 return -EINVAL;
482 }
483
484 if (plane->flags != VFIO_GFX_PLANE_TYPE_REGION)
485 return -EINVAL;
486
487 plane->drm_format = mdev_state->type->format;
488 plane->width = mdev_state->type->width;
489 plane->height = mdev_state->type->height;
490 plane->stride = (mdev_state->type->width *
491 mdev_state->type->bytepp);
492 plane->size = mdev_state->memsize;
493 plane->region_index = MDPY_DISPLAY_REGION;
494
495 /* unused */
496 plane->drm_format_mod = 0;
497 plane->x_pos = 0;
498 plane->y_pos = 0;
499 plane->x_hot = 0;
500 plane->y_hot = 0;
501
502 return 0;
503 }
504
mdpy_ioctl(struct vfio_device * vdev,unsigned int cmd,unsigned long arg)505 static long mdpy_ioctl(struct vfio_device *vdev, unsigned int cmd,
506 unsigned long arg)
507 {
508 int ret = 0;
509 unsigned long minsz;
510 struct mdev_state *mdev_state =
511 container_of(vdev, struct mdev_state, vdev);
512
513 switch (cmd) {
514 case VFIO_DEVICE_GET_INFO:
515 {
516 struct vfio_device_info info;
517
518 minsz = offsetofend(struct vfio_device_info, num_irqs);
519
520 if (copy_from_user(&info, (void __user *)arg, minsz))
521 return -EFAULT;
522
523 if (info.argsz < minsz)
524 return -EINVAL;
525
526 ret = mdpy_get_device_info(&info);
527 if (ret)
528 return ret;
529
530 memcpy(&mdev_state->dev_info, &info, sizeof(info));
531
532 if (copy_to_user((void __user *)arg, &info, minsz))
533 return -EFAULT;
534
535 return 0;
536 }
537 case VFIO_DEVICE_GET_REGION_INFO:
538 {
539 struct vfio_region_info info;
540 u16 cap_type_id = 0;
541 void *cap_type = NULL;
542
543 minsz = offsetofend(struct vfio_region_info, offset);
544
545 if (copy_from_user(&info, (void __user *)arg, minsz))
546 return -EFAULT;
547
548 if (info.argsz < minsz)
549 return -EINVAL;
550
551 ret = mdpy_get_region_info(mdev_state, &info, &cap_type_id,
552 &cap_type);
553 if (ret)
554 return ret;
555
556 if (copy_to_user((void __user *)arg, &info, minsz))
557 return -EFAULT;
558
559 return 0;
560 }
561
562 case VFIO_DEVICE_GET_IRQ_INFO:
563 {
564 struct vfio_irq_info info;
565
566 minsz = offsetofend(struct vfio_irq_info, count);
567
568 if (copy_from_user(&info, (void __user *)arg, minsz))
569 return -EFAULT;
570
571 if ((info.argsz < minsz) ||
572 (info.index >= mdev_state->dev_info.num_irqs))
573 return -EINVAL;
574
575 ret = mdpy_get_irq_info(&info);
576 if (ret)
577 return ret;
578
579 if (copy_to_user((void __user *)arg, &info, minsz))
580 return -EFAULT;
581
582 return 0;
583 }
584
585 case VFIO_DEVICE_QUERY_GFX_PLANE:
586 {
587 struct vfio_device_gfx_plane_info plane;
588
589 minsz = offsetofend(struct vfio_device_gfx_plane_info,
590 region_index);
591
592 if (copy_from_user(&plane, (void __user *)arg, minsz))
593 return -EFAULT;
594
595 if (plane.argsz < minsz)
596 return -EINVAL;
597
598 ret = mdpy_query_gfx_plane(mdev_state, &plane);
599 if (ret)
600 return ret;
601
602 if (copy_to_user((void __user *)arg, &plane, minsz))
603 return -EFAULT;
604
605 return 0;
606 }
607
608 case VFIO_DEVICE_SET_IRQS:
609 return -EINVAL;
610
611 case VFIO_DEVICE_RESET:
612 return mdpy_reset(mdev_state);
613 }
614 return -ENOTTY;
615 }
616
617 static ssize_t
resolution_show(struct device * dev,struct device_attribute * attr,char * buf)618 resolution_show(struct device *dev, struct device_attribute *attr,
619 char *buf)
620 {
621 struct mdev_state *mdev_state = dev_get_drvdata(dev);
622
623 return sprintf(buf, "%dx%d\n",
624 mdev_state->type->width,
625 mdev_state->type->height);
626 }
627 static DEVICE_ATTR_RO(resolution);
628
629 static struct attribute *mdev_dev_attrs[] = {
630 &dev_attr_resolution.attr,
631 NULL,
632 };
633
634 static const struct attribute_group mdev_dev_group = {
635 .name = "vendor",
636 .attrs = mdev_dev_attrs,
637 };
638
639 static const struct attribute_group *mdev_dev_groups[] = {
640 &mdev_dev_group,
641 NULL,
642 };
643
name_show(struct mdev_type * mtype,struct mdev_type_attribute * attr,char * buf)644 static ssize_t name_show(struct mdev_type *mtype,
645 struct mdev_type_attribute *attr, char *buf)
646 {
647 const struct mdpy_type *type =
648 &mdpy_types[mtype_get_type_group_id(mtype)];
649
650 return sprintf(buf, "%s\n", type->name);
651 }
652 static MDEV_TYPE_ATTR_RO(name);
653
description_show(struct mdev_type * mtype,struct mdev_type_attribute * attr,char * buf)654 static ssize_t description_show(struct mdev_type *mtype,
655 struct mdev_type_attribute *attr, char *buf)
656 {
657 const struct mdpy_type *type =
658 &mdpy_types[mtype_get_type_group_id(mtype)];
659
660 return sprintf(buf, "virtual display, %dx%d framebuffer\n",
661 type->width, type->height);
662 }
663 static MDEV_TYPE_ATTR_RO(description);
664
available_instances_show(struct mdev_type * mtype,struct mdev_type_attribute * attr,char * buf)665 static ssize_t available_instances_show(struct mdev_type *mtype,
666 struct mdev_type_attribute *attr,
667 char *buf)
668 {
669 return sprintf(buf, "%d\n", max_devices - mdpy_count);
670 }
671 static MDEV_TYPE_ATTR_RO(available_instances);
672
device_api_show(struct mdev_type * mtype,struct mdev_type_attribute * attr,char * buf)673 static ssize_t device_api_show(struct mdev_type *mtype,
674 struct mdev_type_attribute *attr, char *buf)
675 {
676 return sprintf(buf, "%s\n", VFIO_DEVICE_API_PCI_STRING);
677 }
678 static MDEV_TYPE_ATTR_RO(device_api);
679
680 static struct attribute *mdev_types_attrs[] = {
681 &mdev_type_attr_name.attr,
682 &mdev_type_attr_description.attr,
683 &mdev_type_attr_device_api.attr,
684 &mdev_type_attr_available_instances.attr,
685 NULL,
686 };
687
688 static struct attribute_group mdev_type_group1 = {
689 .name = MDPY_TYPE_1,
690 .attrs = mdev_types_attrs,
691 };
692
693 static struct attribute_group mdev_type_group2 = {
694 .name = MDPY_TYPE_2,
695 .attrs = mdev_types_attrs,
696 };
697
698 static struct attribute_group mdev_type_group3 = {
699 .name = MDPY_TYPE_3,
700 .attrs = mdev_types_attrs,
701 };
702
703 static struct attribute_group *mdev_type_groups[] = {
704 &mdev_type_group1,
705 &mdev_type_group2,
706 &mdev_type_group3,
707 NULL,
708 };
709
710 static const struct vfio_device_ops mdpy_dev_ops = {
711 .read = mdpy_read,
712 .write = mdpy_write,
713 .ioctl = mdpy_ioctl,
714 .mmap = mdpy_mmap,
715 };
716
717 static struct mdev_driver mdpy_driver = {
718 .driver = {
719 .name = "mdpy",
720 .owner = THIS_MODULE,
721 .mod_name = KBUILD_MODNAME,
722 .dev_groups = mdev_dev_groups,
723 },
724 .probe = mdpy_probe,
725 .remove = mdpy_remove,
726 };
727
728 static const struct mdev_parent_ops mdev_fops = {
729 .owner = THIS_MODULE,
730 .device_driver = &mdpy_driver,
731 .supported_type_groups = mdev_type_groups,
732 };
733
734 static const struct file_operations vd_fops = {
735 .owner = THIS_MODULE,
736 };
737
mdpy_device_release(struct device * dev)738 static void mdpy_device_release(struct device *dev)
739 {
740 /* nothing */
741 }
742
mdpy_dev_init(void)743 static int __init mdpy_dev_init(void)
744 {
745 int ret = 0;
746
747 ret = alloc_chrdev_region(&mdpy_devt, 0, MINORMASK + 1, MDPY_NAME);
748 if (ret < 0) {
749 pr_err("Error: failed to register mdpy_dev, err: %d\n", ret);
750 return ret;
751 }
752 cdev_init(&mdpy_cdev, &vd_fops);
753 cdev_add(&mdpy_cdev, mdpy_devt, MINORMASK + 1);
754 pr_info("%s: major %d\n", __func__, MAJOR(mdpy_devt));
755
756 ret = mdev_register_driver(&mdpy_driver);
757 if (ret)
758 goto err_cdev;
759
760 mdpy_class = class_create(THIS_MODULE, MDPY_CLASS_NAME);
761 if (IS_ERR(mdpy_class)) {
762 pr_err("Error: failed to register mdpy_dev class\n");
763 ret = PTR_ERR(mdpy_class);
764 goto err_driver;
765 }
766 mdpy_dev.class = mdpy_class;
767 mdpy_dev.release = mdpy_device_release;
768 dev_set_name(&mdpy_dev, "%s", MDPY_NAME);
769
770 ret = device_register(&mdpy_dev);
771 if (ret)
772 goto err_class;
773
774 ret = mdev_register_device(&mdpy_dev, &mdev_fops);
775 if (ret)
776 goto err_device;
777
778 return 0;
779
780 err_device:
781 device_unregister(&mdpy_dev);
782 err_class:
783 class_destroy(mdpy_class);
784 err_driver:
785 mdev_unregister_driver(&mdpy_driver);
786 err_cdev:
787 cdev_del(&mdpy_cdev);
788 unregister_chrdev_region(mdpy_devt, MINORMASK + 1);
789 return ret;
790 }
791
mdpy_dev_exit(void)792 static void __exit mdpy_dev_exit(void)
793 {
794 mdpy_dev.bus = NULL;
795 mdev_unregister_device(&mdpy_dev);
796
797 device_unregister(&mdpy_dev);
798 mdev_unregister_driver(&mdpy_driver);
799 cdev_del(&mdpy_cdev);
800 unregister_chrdev_region(mdpy_devt, MINORMASK + 1);
801 class_destroy(mdpy_class);
802 mdpy_class = NULL;
803 }
804
805 module_init(mdpy_dev_init)
806 module_exit(mdpy_dev_exit)
807