xref: /openbmc/linux/samples/vfio-mdev/mbochs.c (revision c4f7ac64)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Mediated virtual PCI display host device driver
4  *
5  * Emulate enough of qemu stdvga to make bochs-drm.ko happy.  That is
6  * basically the vram memory bar and the bochs dispi interface vbe
7  * registers in the mmio register bar.	Specifically it does *not*
8  * include any legacy vga stuff.  Device looks a lot like "qemu -device
9  * secondary-vga".
10  *
11  *   (c) Gerd Hoffmann <kraxel@redhat.com>
12  *
13  * based on mtty driver which is:
14  *   Copyright (c) 2016, NVIDIA CORPORATION. All rights reserved.
15  *	 Author: Neo Jia <cjia@nvidia.com>
16  *		 Kirti Wankhede <kwankhede@nvidia.com>
17  *
18  * This program is free software; you can redistribute it and/or modify
19  * it under the terms of the GNU General Public License version 2 as
20  * published by the Free Software Foundation.
21  */
22 #include <linux/init.h>
23 #include <linux/module.h>
24 #include <linux/device.h>
25 #include <linux/kernel.h>
26 #include <linux/slab.h>
27 #include <linux/vmalloc.h>
28 #include <linux/cdev.h>
29 #include <linux/vfio.h>
30 #include <linux/iommu.h>
31 #include <linux/sysfs.h>
32 #include <linux/mdev.h>
33 #include <linux/pci.h>
34 #include <linux/dma-buf.h>
35 #include <linux/highmem.h>
36 #include <drm/drm_fourcc.h>
37 #include <drm/drm_rect.h>
38 #include <drm/drm_modeset_lock.h>
39 #include <drm/drm_property.h>
40 #include <drm/drm_plane.h>
41 
42 
43 #define VBE_DISPI_INDEX_ID		0x0
44 #define VBE_DISPI_INDEX_XRES		0x1
45 #define VBE_DISPI_INDEX_YRES		0x2
46 #define VBE_DISPI_INDEX_BPP		0x3
47 #define VBE_DISPI_INDEX_ENABLE		0x4
48 #define VBE_DISPI_INDEX_BANK		0x5
49 #define VBE_DISPI_INDEX_VIRT_WIDTH	0x6
50 #define VBE_DISPI_INDEX_VIRT_HEIGHT	0x7
51 #define VBE_DISPI_INDEX_X_OFFSET	0x8
52 #define VBE_DISPI_INDEX_Y_OFFSET	0x9
53 #define VBE_DISPI_INDEX_VIDEO_MEMORY_64K 0xa
54 #define VBE_DISPI_INDEX_COUNT		0xb
55 
56 #define VBE_DISPI_ID0			0xB0C0
57 #define VBE_DISPI_ID1			0xB0C1
58 #define VBE_DISPI_ID2			0xB0C2
59 #define VBE_DISPI_ID3			0xB0C3
60 #define VBE_DISPI_ID4			0xB0C4
61 #define VBE_DISPI_ID5			0xB0C5
62 
63 #define VBE_DISPI_DISABLED		0x00
64 #define VBE_DISPI_ENABLED		0x01
65 #define VBE_DISPI_GETCAPS		0x02
66 #define VBE_DISPI_8BIT_DAC		0x20
67 #define VBE_DISPI_LFB_ENABLED		0x40
68 #define VBE_DISPI_NOCLEARMEM		0x80
69 
70 
71 #define MBOCHS_NAME		  "mbochs"
72 #define MBOCHS_CLASS_NAME	  "mbochs"
73 
74 #define MBOCHS_EDID_REGION_INDEX  VFIO_PCI_NUM_REGIONS
75 #define MBOCHS_NUM_REGIONS        (MBOCHS_EDID_REGION_INDEX+1)
76 
77 #define MBOCHS_CONFIG_SPACE_SIZE  0xff
78 #define MBOCHS_MMIO_BAR_OFFSET	  PAGE_SIZE
79 #define MBOCHS_MMIO_BAR_SIZE	  PAGE_SIZE
80 #define MBOCHS_EDID_OFFSET	  (MBOCHS_MMIO_BAR_OFFSET +	\
81 				   MBOCHS_MMIO_BAR_SIZE)
82 #define MBOCHS_EDID_SIZE	  PAGE_SIZE
83 #define MBOCHS_MEMORY_BAR_OFFSET  (MBOCHS_EDID_OFFSET + \
84 				   MBOCHS_EDID_SIZE)
85 
86 #define MBOCHS_EDID_BLOB_OFFSET   (MBOCHS_EDID_SIZE/2)
87 
88 #define STORE_LE16(addr, val)	(*(u16 *)addr = val)
89 #define STORE_LE32(addr, val)	(*(u32 *)addr = val)
90 
91 
92 MODULE_LICENSE("GPL v2");
93 
94 static int max_mbytes = 256;
95 module_param_named(count, max_mbytes, int, 0444);
96 MODULE_PARM_DESC(mem, "megabytes available to " MBOCHS_NAME " devices");
97 
98 
99 #define MBOCHS_TYPE_1 "small"
100 #define MBOCHS_TYPE_2 "medium"
101 #define MBOCHS_TYPE_3 "large"
102 
103 static const struct mbochs_type {
104 	const char *name;
105 	u32 mbytes;
106 	u32 max_x;
107 	u32 max_y;
108 } mbochs_types[] = {
109 	{
110 		.name	= MBOCHS_CLASS_NAME "-" MBOCHS_TYPE_1,
111 		.mbytes = 4,
112 		.max_x  = 800,
113 		.max_y  = 600,
114 	}, {
115 		.name	= MBOCHS_CLASS_NAME "-" MBOCHS_TYPE_2,
116 		.mbytes = 16,
117 		.max_x  = 1920,
118 		.max_y  = 1440,
119 	}, {
120 		.name	= MBOCHS_CLASS_NAME "-" MBOCHS_TYPE_3,
121 		.mbytes = 64,
122 		.max_x  = 0,
123 		.max_y  = 0,
124 	},
125 };
126 
127 
128 static dev_t		mbochs_devt;
129 static struct class	*mbochs_class;
130 static struct cdev	mbochs_cdev;
131 static struct device	mbochs_dev;
132 static int		mbochs_used_mbytes;
133 
134 struct vfio_region_info_ext {
135 	struct vfio_region_info          base;
136 	struct vfio_region_info_cap_type type;
137 };
138 
139 struct mbochs_mode {
140 	u32 drm_format;
141 	u32 bytepp;
142 	u32 width;
143 	u32 height;
144 	u32 stride;
145 	u32 __pad;
146 	u64 offset;
147 	u64 size;
148 };
149 
150 struct mbochs_dmabuf {
151 	struct mbochs_mode mode;
152 	u32 id;
153 	struct page **pages;
154 	pgoff_t pagecount;
155 	struct dma_buf *buf;
156 	struct mdev_state *mdev_state;
157 	struct list_head next;
158 	bool unlinked;
159 };
160 
161 /* State of each mdev device */
162 struct mdev_state {
163 	u8 *vconfig;
164 	u64 bar_mask[3];
165 	u32 memory_bar_mask;
166 	struct mutex ops_lock;
167 	struct mdev_device *mdev;
168 
169 	const struct mbochs_type *type;
170 	u16 vbe[VBE_DISPI_INDEX_COUNT];
171 	u64 memsize;
172 	struct page **pages;
173 	pgoff_t pagecount;
174 	struct vfio_region_gfx_edid edid_regs;
175 	u8 edid_blob[0x400];
176 
177 	struct list_head dmabufs;
178 	u32 active_id;
179 	u32 next_id;
180 };
181 
182 static const char *vbe_name_list[VBE_DISPI_INDEX_COUNT] = {
183 	[VBE_DISPI_INDEX_ID]               = "id",
184 	[VBE_DISPI_INDEX_XRES]             = "xres",
185 	[VBE_DISPI_INDEX_YRES]             = "yres",
186 	[VBE_DISPI_INDEX_BPP]              = "bpp",
187 	[VBE_DISPI_INDEX_ENABLE]           = "enable",
188 	[VBE_DISPI_INDEX_BANK]             = "bank",
189 	[VBE_DISPI_INDEX_VIRT_WIDTH]       = "virt-width",
190 	[VBE_DISPI_INDEX_VIRT_HEIGHT]      = "virt-height",
191 	[VBE_DISPI_INDEX_X_OFFSET]         = "x-offset",
192 	[VBE_DISPI_INDEX_Y_OFFSET]         = "y-offset",
193 	[VBE_DISPI_INDEX_VIDEO_MEMORY_64K] = "video-mem",
194 };
195 
196 static const char *vbe_name(u32 index)
197 {
198 	if (index < ARRAY_SIZE(vbe_name_list))
199 		return vbe_name_list[index];
200 	return "(invalid)";
201 }
202 
203 static struct page *__mbochs_get_page(struct mdev_state *mdev_state,
204 				      pgoff_t pgoff);
205 static struct page *mbochs_get_page(struct mdev_state *mdev_state,
206 				    pgoff_t pgoff);
207 
208 static void mbochs_create_config_space(struct mdev_state *mdev_state)
209 {
210 	STORE_LE16((u16 *) &mdev_state->vconfig[PCI_VENDOR_ID],
211 		   0x1234);
212 	STORE_LE16((u16 *) &mdev_state->vconfig[PCI_DEVICE_ID],
213 		   0x1111);
214 	STORE_LE16((u16 *) &mdev_state->vconfig[PCI_SUBSYSTEM_VENDOR_ID],
215 		   PCI_SUBVENDOR_ID_REDHAT_QUMRANET);
216 	STORE_LE16((u16 *) &mdev_state->vconfig[PCI_SUBSYSTEM_ID],
217 		   PCI_SUBDEVICE_ID_QEMU);
218 
219 	STORE_LE16((u16 *) &mdev_state->vconfig[PCI_COMMAND],
220 		   PCI_COMMAND_IO | PCI_COMMAND_MEMORY);
221 	STORE_LE16((u16 *) &mdev_state->vconfig[PCI_CLASS_DEVICE],
222 		   PCI_CLASS_DISPLAY_OTHER);
223 	mdev_state->vconfig[PCI_CLASS_REVISION] =  0x01;
224 
225 	STORE_LE32((u32 *) &mdev_state->vconfig[PCI_BASE_ADDRESS_0],
226 		   PCI_BASE_ADDRESS_SPACE_MEMORY |
227 		   PCI_BASE_ADDRESS_MEM_TYPE_32	 |
228 		   PCI_BASE_ADDRESS_MEM_PREFETCH);
229 	mdev_state->bar_mask[0] = ~(mdev_state->memsize) + 1;
230 
231 	STORE_LE32((u32 *) &mdev_state->vconfig[PCI_BASE_ADDRESS_2],
232 		   PCI_BASE_ADDRESS_SPACE_MEMORY |
233 		   PCI_BASE_ADDRESS_MEM_TYPE_32);
234 	mdev_state->bar_mask[2] = ~(MBOCHS_MMIO_BAR_SIZE) + 1;
235 }
236 
237 static int mbochs_check_framebuffer(struct mdev_state *mdev_state,
238 				    struct mbochs_mode *mode)
239 {
240 	struct device *dev = mdev_dev(mdev_state->mdev);
241 	u16 *vbe = mdev_state->vbe;
242 	u32 virt_width;
243 
244 	WARN_ON(!mutex_is_locked(&mdev_state->ops_lock));
245 
246 	if (!(vbe[VBE_DISPI_INDEX_ENABLE] & VBE_DISPI_ENABLED))
247 		goto nofb;
248 
249 	memset(mode, 0, sizeof(*mode));
250 	switch (vbe[VBE_DISPI_INDEX_BPP]) {
251 	case 32:
252 		mode->drm_format = DRM_FORMAT_XRGB8888;
253 		mode->bytepp = 4;
254 		break;
255 	default:
256 		dev_info_ratelimited(dev, "%s: bpp %d not supported\n",
257 				     __func__, vbe[VBE_DISPI_INDEX_BPP]);
258 		goto nofb;
259 	}
260 
261 	mode->width  = vbe[VBE_DISPI_INDEX_XRES];
262 	mode->height = vbe[VBE_DISPI_INDEX_YRES];
263 	virt_width  = vbe[VBE_DISPI_INDEX_VIRT_WIDTH];
264 	if (virt_width < mode->width)
265 		virt_width = mode->width;
266 	mode->stride = virt_width * mode->bytepp;
267 	mode->size   = (u64)mode->stride * mode->height;
268 	mode->offset = ((u64)vbe[VBE_DISPI_INDEX_X_OFFSET] * mode->bytepp +
269 		       (u64)vbe[VBE_DISPI_INDEX_Y_OFFSET] * mode->stride);
270 
271 	if (mode->width < 64 || mode->height < 64) {
272 		dev_info_ratelimited(dev, "%s: invalid resolution %dx%d\n",
273 				     __func__, mode->width, mode->height);
274 		goto nofb;
275 	}
276 	if (mode->offset + mode->size > mdev_state->memsize) {
277 		dev_info_ratelimited(dev, "%s: framebuffer memory overflow\n",
278 				     __func__);
279 		goto nofb;
280 	}
281 
282 	return 0;
283 
284 nofb:
285 	memset(mode, 0, sizeof(*mode));
286 	return -EINVAL;
287 }
288 
289 static bool mbochs_modes_equal(struct mbochs_mode *mode1,
290 			       struct mbochs_mode *mode2)
291 {
292 	return memcmp(mode1, mode2, sizeof(struct mbochs_mode)) == 0;
293 }
294 
295 static void handle_pci_cfg_write(struct mdev_state *mdev_state, u16 offset,
296 				 char *buf, u32 count)
297 {
298 	struct device *dev = mdev_dev(mdev_state->mdev);
299 	int index = (offset - PCI_BASE_ADDRESS_0) / 0x04;
300 	u32 cfg_addr;
301 
302 	switch (offset) {
303 	case PCI_BASE_ADDRESS_0:
304 	case PCI_BASE_ADDRESS_2:
305 		cfg_addr = *(u32 *)buf;
306 
307 		if (cfg_addr == 0xffffffff) {
308 			cfg_addr = (cfg_addr & mdev_state->bar_mask[index]);
309 		} else {
310 			cfg_addr &= PCI_BASE_ADDRESS_MEM_MASK;
311 			if (cfg_addr)
312 				dev_info(dev, "BAR #%d @ 0x%x\n",
313 					 index, cfg_addr);
314 		}
315 
316 		cfg_addr |= (mdev_state->vconfig[offset] &
317 			     ~PCI_BASE_ADDRESS_MEM_MASK);
318 		STORE_LE32(&mdev_state->vconfig[offset], cfg_addr);
319 		break;
320 	}
321 }
322 
323 static void handle_mmio_write(struct mdev_state *mdev_state, u16 offset,
324 			      char *buf, u32 count)
325 {
326 	struct device *dev = mdev_dev(mdev_state->mdev);
327 	int index;
328 	u16 reg16;
329 
330 	switch (offset) {
331 	case 0x400 ... 0x41f: /* vga ioports remapped */
332 		goto unhandled;
333 	case 0x500 ... 0x515: /* bochs dispi interface */
334 		if (count != 2)
335 			goto unhandled;
336 		index = (offset - 0x500) / 2;
337 		reg16 = *(u16 *)buf;
338 		if (index < ARRAY_SIZE(mdev_state->vbe))
339 			mdev_state->vbe[index] = reg16;
340 		dev_dbg(dev, "%s: vbe write %d = %d (%s)\n",
341 			__func__, index, reg16, vbe_name(index));
342 		break;
343 	case 0x600 ... 0x607: /* qemu extended regs */
344 		goto unhandled;
345 	default:
346 unhandled:
347 		dev_dbg(dev, "%s: @0x%03x, count %d (unhandled)\n",
348 			__func__, offset, count);
349 		break;
350 	}
351 }
352 
353 static void handle_mmio_read(struct mdev_state *mdev_state, u16 offset,
354 			     char *buf, u32 count)
355 {
356 	struct device *dev = mdev_dev(mdev_state->mdev);
357 	struct vfio_region_gfx_edid *edid;
358 	u16 reg16 = 0;
359 	int index;
360 
361 	switch (offset) {
362 	case 0x000 ... 0x3ff: /* edid block */
363 		edid = &mdev_state->edid_regs;
364 		if (edid->link_state != VFIO_DEVICE_GFX_LINK_STATE_UP ||
365 		    offset >= edid->edid_size) {
366 			memset(buf, 0, count);
367 			break;
368 		}
369 		memcpy(buf, mdev_state->edid_blob + offset, count);
370 		break;
371 	case 0x500 ... 0x515: /* bochs dispi interface */
372 		if (count != 2)
373 			goto unhandled;
374 		index = (offset - 0x500) / 2;
375 		if (index < ARRAY_SIZE(mdev_state->vbe))
376 			reg16 = mdev_state->vbe[index];
377 		dev_dbg(dev, "%s: vbe read %d = %d (%s)\n",
378 			__func__, index, reg16, vbe_name(index));
379 		*(u16 *)buf = reg16;
380 		break;
381 	default:
382 unhandled:
383 		dev_dbg(dev, "%s: @0x%03x, count %d (unhandled)\n",
384 			__func__, offset, count);
385 		memset(buf, 0, count);
386 		break;
387 	}
388 }
389 
390 static void handle_edid_regs(struct mdev_state *mdev_state, u16 offset,
391 			     char *buf, u32 count, bool is_write)
392 {
393 	char *regs = (void *)&mdev_state->edid_regs;
394 
395 	if (offset + count > sizeof(mdev_state->edid_regs))
396 		return;
397 	if (count != 4)
398 		return;
399 	if (offset % 4)
400 		return;
401 
402 	if (is_write) {
403 		switch (offset) {
404 		case offsetof(struct vfio_region_gfx_edid, link_state):
405 		case offsetof(struct vfio_region_gfx_edid, edid_size):
406 			memcpy(regs + offset, buf, count);
407 			break;
408 		default:
409 			/* read-only regs */
410 			break;
411 		}
412 	} else {
413 		memcpy(buf, regs + offset, count);
414 	}
415 }
416 
417 static void handle_edid_blob(struct mdev_state *mdev_state, u16 offset,
418 			     char *buf, u32 count, bool is_write)
419 {
420 	if (offset + count > mdev_state->edid_regs.edid_max_size)
421 		return;
422 	if (is_write)
423 		memcpy(mdev_state->edid_blob + offset, buf, count);
424 	else
425 		memcpy(buf, mdev_state->edid_blob + offset, count);
426 }
427 
428 static ssize_t mdev_access(struct mdev_device *mdev, char *buf, size_t count,
429 			   loff_t pos, bool is_write)
430 {
431 	struct mdev_state *mdev_state = mdev_get_drvdata(mdev);
432 	struct device *dev = mdev_dev(mdev);
433 	struct page *pg;
434 	loff_t poff;
435 	char *map;
436 	int ret = 0;
437 
438 	mutex_lock(&mdev_state->ops_lock);
439 
440 	if (pos < MBOCHS_CONFIG_SPACE_SIZE) {
441 		if (is_write)
442 			handle_pci_cfg_write(mdev_state, pos, buf, count);
443 		else
444 			memcpy(buf, (mdev_state->vconfig + pos), count);
445 
446 	} else if (pos >= MBOCHS_MMIO_BAR_OFFSET &&
447 		   pos + count <= (MBOCHS_MMIO_BAR_OFFSET +
448 				   MBOCHS_MMIO_BAR_SIZE)) {
449 		pos -= MBOCHS_MMIO_BAR_OFFSET;
450 		if (is_write)
451 			handle_mmio_write(mdev_state, pos, buf, count);
452 		else
453 			handle_mmio_read(mdev_state, pos, buf, count);
454 
455 	} else if (pos >= MBOCHS_EDID_OFFSET &&
456 		   pos + count <= (MBOCHS_EDID_OFFSET +
457 				   MBOCHS_EDID_SIZE)) {
458 		pos -= MBOCHS_EDID_OFFSET;
459 		if (pos < MBOCHS_EDID_BLOB_OFFSET) {
460 			handle_edid_regs(mdev_state, pos, buf, count, is_write);
461 		} else {
462 			pos -= MBOCHS_EDID_BLOB_OFFSET;
463 			handle_edid_blob(mdev_state, pos, buf, count, is_write);
464 		}
465 
466 	} else if (pos >= MBOCHS_MEMORY_BAR_OFFSET &&
467 		   pos + count <=
468 		   MBOCHS_MEMORY_BAR_OFFSET + mdev_state->memsize) {
469 		pos -= MBOCHS_MMIO_BAR_OFFSET;
470 		poff = pos & ~PAGE_MASK;
471 		pg = __mbochs_get_page(mdev_state, pos >> PAGE_SHIFT);
472 		map = kmap(pg);
473 		if (is_write)
474 			memcpy(map + poff, buf, count);
475 		else
476 			memcpy(buf, map + poff, count);
477 		kunmap(pg);
478 		put_page(pg);
479 
480 	} else {
481 		dev_dbg(dev, "%s: %s @0x%llx (unhandled)\n",
482 			__func__, is_write ? "WR" : "RD", pos);
483 		ret = -1;
484 		goto accessfailed;
485 	}
486 
487 	ret = count;
488 
489 
490 accessfailed:
491 	mutex_unlock(&mdev_state->ops_lock);
492 
493 	return ret;
494 }
495 
496 static int mbochs_reset(struct mdev_device *mdev)
497 {
498 	struct mdev_state *mdev_state = mdev_get_drvdata(mdev);
499 	u32 size64k = mdev_state->memsize / (64 * 1024);
500 	int i;
501 
502 	for (i = 0; i < ARRAY_SIZE(mdev_state->vbe); i++)
503 		mdev_state->vbe[i] = 0;
504 	mdev_state->vbe[VBE_DISPI_INDEX_ID] = VBE_DISPI_ID5;
505 	mdev_state->vbe[VBE_DISPI_INDEX_VIDEO_MEMORY_64K] = size64k;
506 	return 0;
507 }
508 
509 static int mbochs_create(struct mdev_device *mdev)
510 {
511 	const struct mbochs_type *type =
512 		&mbochs_types[mdev_get_type_group_id(mdev)];
513 	struct device *dev = mdev_dev(mdev);
514 	struct mdev_state *mdev_state;
515 
516 	if (type->mbytes + mbochs_used_mbytes > max_mbytes)
517 		return -ENOMEM;
518 
519 	mdev_state = kzalloc(sizeof(struct mdev_state), GFP_KERNEL);
520 	if (mdev_state == NULL)
521 		return -ENOMEM;
522 
523 	mdev_state->vconfig = kzalloc(MBOCHS_CONFIG_SPACE_SIZE, GFP_KERNEL);
524 	if (mdev_state->vconfig == NULL)
525 		goto err_mem;
526 
527 	mdev_state->memsize = type->mbytes * 1024 * 1024;
528 	mdev_state->pagecount = mdev_state->memsize >> PAGE_SHIFT;
529 	mdev_state->pages = kcalloc(mdev_state->pagecount,
530 				    sizeof(struct page *),
531 				    GFP_KERNEL);
532 	if (!mdev_state->pages)
533 		goto err_mem;
534 
535 	dev_info(dev, "%s: %s, %d MB, %ld pages\n", __func__,
536 		 type->name, type->mbytes, mdev_state->pagecount);
537 
538 	mutex_init(&mdev_state->ops_lock);
539 	mdev_state->mdev = mdev;
540 	mdev_set_drvdata(mdev, mdev_state);
541 	INIT_LIST_HEAD(&mdev_state->dmabufs);
542 	mdev_state->next_id = 1;
543 
544 	mdev_state->type = type;
545 	mdev_state->edid_regs.max_xres = type->max_x;
546 	mdev_state->edid_regs.max_yres = type->max_y;
547 	mdev_state->edid_regs.edid_offset = MBOCHS_EDID_BLOB_OFFSET;
548 	mdev_state->edid_regs.edid_max_size = sizeof(mdev_state->edid_blob);
549 	mbochs_create_config_space(mdev_state);
550 	mbochs_reset(mdev);
551 
552 	mbochs_used_mbytes += type->mbytes;
553 	return 0;
554 
555 err_mem:
556 	kfree(mdev_state->vconfig);
557 	kfree(mdev_state);
558 	return -ENOMEM;
559 }
560 
561 static int mbochs_remove(struct mdev_device *mdev)
562 {
563 	struct mdev_state *mdev_state = mdev_get_drvdata(mdev);
564 
565 	mbochs_used_mbytes -= mdev_state->type->mbytes;
566 	mdev_set_drvdata(mdev, NULL);
567 	kfree(mdev_state->pages);
568 	kfree(mdev_state->vconfig);
569 	kfree(mdev_state);
570 	return 0;
571 }
572 
573 static ssize_t mbochs_read(struct mdev_device *mdev, char __user *buf,
574 			   size_t count, loff_t *ppos)
575 {
576 	unsigned int done = 0;
577 	int ret;
578 
579 	while (count) {
580 		size_t filled;
581 
582 		if (count >= 4 && !(*ppos % 4)) {
583 			u32 val;
584 
585 			ret =  mdev_access(mdev, (char *)&val, sizeof(val),
586 					   *ppos, false);
587 			if (ret <= 0)
588 				goto read_err;
589 
590 			if (copy_to_user(buf, &val, sizeof(val)))
591 				goto read_err;
592 
593 			filled = 4;
594 		} else if (count >= 2 && !(*ppos % 2)) {
595 			u16 val;
596 
597 			ret = mdev_access(mdev, (char *)&val, sizeof(val),
598 					  *ppos, false);
599 			if (ret <= 0)
600 				goto read_err;
601 
602 			if (copy_to_user(buf, &val, sizeof(val)))
603 				goto read_err;
604 
605 			filled = 2;
606 		} else {
607 			u8 val;
608 
609 			ret = mdev_access(mdev, (char *)&val, sizeof(val),
610 					  *ppos, false);
611 			if (ret <= 0)
612 				goto read_err;
613 
614 			if (copy_to_user(buf, &val, sizeof(val)))
615 				goto read_err;
616 
617 			filled = 1;
618 		}
619 
620 		count -= filled;
621 		done += filled;
622 		*ppos += filled;
623 		buf += filled;
624 	}
625 
626 	return done;
627 
628 read_err:
629 	return -EFAULT;
630 }
631 
632 static ssize_t mbochs_write(struct mdev_device *mdev, const char __user *buf,
633 			    size_t count, loff_t *ppos)
634 {
635 	unsigned int done = 0;
636 	int ret;
637 
638 	while (count) {
639 		size_t filled;
640 
641 		if (count >= 4 && !(*ppos % 4)) {
642 			u32 val;
643 
644 			if (copy_from_user(&val, buf, sizeof(val)))
645 				goto write_err;
646 
647 			ret = mdev_access(mdev, (char *)&val, sizeof(val),
648 					  *ppos, true);
649 			if (ret <= 0)
650 				goto write_err;
651 
652 			filled = 4;
653 		} else if (count >= 2 && !(*ppos % 2)) {
654 			u16 val;
655 
656 			if (copy_from_user(&val, buf, sizeof(val)))
657 				goto write_err;
658 
659 			ret = mdev_access(mdev, (char *)&val, sizeof(val),
660 					  *ppos, true);
661 			if (ret <= 0)
662 				goto write_err;
663 
664 			filled = 2;
665 		} else {
666 			u8 val;
667 
668 			if (copy_from_user(&val, buf, sizeof(val)))
669 				goto write_err;
670 
671 			ret = mdev_access(mdev, (char *)&val, sizeof(val),
672 					  *ppos, true);
673 			if (ret <= 0)
674 				goto write_err;
675 
676 			filled = 1;
677 		}
678 		count -= filled;
679 		done += filled;
680 		*ppos += filled;
681 		buf += filled;
682 	}
683 
684 	return done;
685 write_err:
686 	return -EFAULT;
687 }
688 
689 static struct page *__mbochs_get_page(struct mdev_state *mdev_state,
690 				      pgoff_t pgoff)
691 {
692 	WARN_ON(!mutex_is_locked(&mdev_state->ops_lock));
693 
694 	if (!mdev_state->pages[pgoff]) {
695 		mdev_state->pages[pgoff] =
696 			alloc_pages(GFP_HIGHUSER | __GFP_ZERO, 0);
697 		if (!mdev_state->pages[pgoff])
698 			return NULL;
699 	}
700 
701 	get_page(mdev_state->pages[pgoff]);
702 	return mdev_state->pages[pgoff];
703 }
704 
705 static struct page *mbochs_get_page(struct mdev_state *mdev_state,
706 				    pgoff_t pgoff)
707 {
708 	struct page *page;
709 
710 	if (WARN_ON(pgoff >= mdev_state->pagecount))
711 		return NULL;
712 
713 	mutex_lock(&mdev_state->ops_lock);
714 	page = __mbochs_get_page(mdev_state, pgoff);
715 	mutex_unlock(&mdev_state->ops_lock);
716 
717 	return page;
718 }
719 
720 static void mbochs_put_pages(struct mdev_state *mdev_state)
721 {
722 	struct device *dev = mdev_dev(mdev_state->mdev);
723 	int i, count = 0;
724 
725 	WARN_ON(!mutex_is_locked(&mdev_state->ops_lock));
726 
727 	for (i = 0; i < mdev_state->pagecount; i++) {
728 		if (!mdev_state->pages[i])
729 			continue;
730 		put_page(mdev_state->pages[i]);
731 		mdev_state->pages[i] = NULL;
732 		count++;
733 	}
734 	dev_dbg(dev, "%s: %d pages released\n", __func__, count);
735 }
736 
737 static vm_fault_t mbochs_region_vm_fault(struct vm_fault *vmf)
738 {
739 	struct vm_area_struct *vma = vmf->vma;
740 	struct mdev_state *mdev_state = vma->vm_private_data;
741 	pgoff_t page_offset = (vmf->address - vma->vm_start) >> PAGE_SHIFT;
742 
743 	if (page_offset >= mdev_state->pagecount)
744 		return VM_FAULT_SIGBUS;
745 
746 	vmf->page = mbochs_get_page(mdev_state, page_offset);
747 	if (!vmf->page)
748 		return VM_FAULT_SIGBUS;
749 
750 	return 0;
751 }
752 
753 static const struct vm_operations_struct mbochs_region_vm_ops = {
754 	.fault = mbochs_region_vm_fault,
755 };
756 
757 static int mbochs_mmap(struct mdev_device *mdev, struct vm_area_struct *vma)
758 {
759 	struct mdev_state *mdev_state = mdev_get_drvdata(mdev);
760 
761 	if (vma->vm_pgoff != MBOCHS_MEMORY_BAR_OFFSET >> PAGE_SHIFT)
762 		return -EINVAL;
763 	if (vma->vm_end < vma->vm_start)
764 		return -EINVAL;
765 	if (vma->vm_end - vma->vm_start > mdev_state->memsize)
766 		return -EINVAL;
767 	if ((vma->vm_flags & VM_SHARED) == 0)
768 		return -EINVAL;
769 
770 	vma->vm_ops = &mbochs_region_vm_ops;
771 	vma->vm_private_data = mdev_state;
772 	return 0;
773 }
774 
775 static vm_fault_t mbochs_dmabuf_vm_fault(struct vm_fault *vmf)
776 {
777 	struct vm_area_struct *vma = vmf->vma;
778 	struct mbochs_dmabuf *dmabuf = vma->vm_private_data;
779 
780 	if (WARN_ON(vmf->pgoff >= dmabuf->pagecount))
781 		return VM_FAULT_SIGBUS;
782 
783 	vmf->page = dmabuf->pages[vmf->pgoff];
784 	get_page(vmf->page);
785 	return 0;
786 }
787 
788 static const struct vm_operations_struct mbochs_dmabuf_vm_ops = {
789 	.fault = mbochs_dmabuf_vm_fault,
790 };
791 
792 static int mbochs_mmap_dmabuf(struct dma_buf *buf, struct vm_area_struct *vma)
793 {
794 	struct mbochs_dmabuf *dmabuf = buf->priv;
795 	struct device *dev = mdev_dev(dmabuf->mdev_state->mdev);
796 
797 	dev_dbg(dev, "%s: %d\n", __func__, dmabuf->id);
798 
799 	if ((vma->vm_flags & VM_SHARED) == 0)
800 		return -EINVAL;
801 
802 	vma->vm_ops = &mbochs_dmabuf_vm_ops;
803 	vma->vm_private_data = dmabuf;
804 	return 0;
805 }
806 
807 static void mbochs_print_dmabuf(struct mbochs_dmabuf *dmabuf,
808 				const char *prefix)
809 {
810 	struct device *dev = mdev_dev(dmabuf->mdev_state->mdev);
811 	u32 fourcc = dmabuf->mode.drm_format;
812 
813 	dev_dbg(dev, "%s/%d: %c%c%c%c, %dx%d, stride %d, off 0x%llx, size 0x%llx, pages %ld\n",
814 		prefix, dmabuf->id,
815 		fourcc ? ((fourcc >>  0) & 0xff) : '-',
816 		fourcc ? ((fourcc >>  8) & 0xff) : '-',
817 		fourcc ? ((fourcc >> 16) & 0xff) : '-',
818 		fourcc ? ((fourcc >> 24) & 0xff) : '-',
819 		dmabuf->mode.width, dmabuf->mode.height, dmabuf->mode.stride,
820 		dmabuf->mode.offset, dmabuf->mode.size, dmabuf->pagecount);
821 }
822 
823 static struct sg_table *mbochs_map_dmabuf(struct dma_buf_attachment *at,
824 					  enum dma_data_direction direction)
825 {
826 	struct mbochs_dmabuf *dmabuf = at->dmabuf->priv;
827 	struct device *dev = mdev_dev(dmabuf->mdev_state->mdev);
828 	struct sg_table *sg;
829 
830 	dev_dbg(dev, "%s: %d\n", __func__, dmabuf->id);
831 
832 	sg = kzalloc(sizeof(*sg), GFP_KERNEL);
833 	if (!sg)
834 		goto err1;
835 	if (sg_alloc_table_from_pages(sg, dmabuf->pages, dmabuf->pagecount,
836 				      0, dmabuf->mode.size, GFP_KERNEL) < 0)
837 		goto err2;
838 	if (dma_map_sgtable(at->dev, sg, direction, 0))
839 		goto err3;
840 
841 	return sg;
842 
843 err3:
844 	sg_free_table(sg);
845 err2:
846 	kfree(sg);
847 err1:
848 	return ERR_PTR(-ENOMEM);
849 }
850 
851 static void mbochs_unmap_dmabuf(struct dma_buf_attachment *at,
852 				struct sg_table *sg,
853 				enum dma_data_direction direction)
854 {
855 	struct mbochs_dmabuf *dmabuf = at->dmabuf->priv;
856 	struct device *dev = mdev_dev(dmabuf->mdev_state->mdev);
857 
858 	dev_dbg(dev, "%s: %d\n", __func__, dmabuf->id);
859 
860 	dma_unmap_sgtable(at->dev, sg, direction, 0);
861 	sg_free_table(sg);
862 	kfree(sg);
863 }
864 
865 static void mbochs_release_dmabuf(struct dma_buf *buf)
866 {
867 	struct mbochs_dmabuf *dmabuf = buf->priv;
868 	struct mdev_state *mdev_state = dmabuf->mdev_state;
869 	struct device *dev = mdev_dev(mdev_state->mdev);
870 	pgoff_t pg;
871 
872 	dev_dbg(dev, "%s: %d\n", __func__, dmabuf->id);
873 
874 	for (pg = 0; pg < dmabuf->pagecount; pg++)
875 		put_page(dmabuf->pages[pg]);
876 
877 	mutex_lock(&mdev_state->ops_lock);
878 	dmabuf->buf = NULL;
879 	if (dmabuf->unlinked)
880 		kfree(dmabuf);
881 	mutex_unlock(&mdev_state->ops_lock);
882 }
883 
884 static struct dma_buf_ops mbochs_dmabuf_ops = {
885 	.map_dma_buf	  = mbochs_map_dmabuf,
886 	.unmap_dma_buf	  = mbochs_unmap_dmabuf,
887 	.release	  = mbochs_release_dmabuf,
888 	.mmap		  = mbochs_mmap_dmabuf,
889 };
890 
891 static struct mbochs_dmabuf *mbochs_dmabuf_alloc(struct mdev_state *mdev_state,
892 						 struct mbochs_mode *mode)
893 {
894 	struct mbochs_dmabuf *dmabuf;
895 	pgoff_t page_offset, pg;
896 
897 	WARN_ON(!mutex_is_locked(&mdev_state->ops_lock));
898 
899 	dmabuf = kzalloc(sizeof(struct mbochs_dmabuf), GFP_KERNEL);
900 	if (!dmabuf)
901 		return NULL;
902 
903 	dmabuf->mode = *mode;
904 	dmabuf->id = mdev_state->next_id++;
905 	dmabuf->pagecount = DIV_ROUND_UP(mode->size, PAGE_SIZE);
906 	dmabuf->pages = kcalloc(dmabuf->pagecount, sizeof(struct page *),
907 				GFP_KERNEL);
908 	if (!dmabuf->pages)
909 		goto err_free_dmabuf;
910 
911 	page_offset = dmabuf->mode.offset >> PAGE_SHIFT;
912 	for (pg = 0; pg < dmabuf->pagecount; pg++) {
913 		dmabuf->pages[pg] = __mbochs_get_page(mdev_state,
914 						      page_offset + pg);
915 		if (!dmabuf->pages[pg])
916 			goto err_free_pages;
917 	}
918 
919 	dmabuf->mdev_state = mdev_state;
920 	list_add(&dmabuf->next, &mdev_state->dmabufs);
921 
922 	mbochs_print_dmabuf(dmabuf, __func__);
923 	return dmabuf;
924 
925 err_free_pages:
926 	while (pg > 0)
927 		put_page(dmabuf->pages[--pg]);
928 	kfree(dmabuf->pages);
929 err_free_dmabuf:
930 	kfree(dmabuf);
931 	return NULL;
932 }
933 
934 static struct mbochs_dmabuf *
935 mbochs_dmabuf_find_by_mode(struct mdev_state *mdev_state,
936 			   struct mbochs_mode *mode)
937 {
938 	struct mbochs_dmabuf *dmabuf;
939 
940 	WARN_ON(!mutex_is_locked(&mdev_state->ops_lock));
941 
942 	list_for_each_entry(dmabuf, &mdev_state->dmabufs, next)
943 		if (mbochs_modes_equal(&dmabuf->mode, mode))
944 			return dmabuf;
945 
946 	return NULL;
947 }
948 
949 static struct mbochs_dmabuf *
950 mbochs_dmabuf_find_by_id(struct mdev_state *mdev_state, u32 id)
951 {
952 	struct mbochs_dmabuf *dmabuf;
953 
954 	WARN_ON(!mutex_is_locked(&mdev_state->ops_lock));
955 
956 	list_for_each_entry(dmabuf, &mdev_state->dmabufs, next)
957 		if (dmabuf->id == id)
958 			return dmabuf;
959 
960 	return NULL;
961 }
962 
963 static int mbochs_dmabuf_export(struct mbochs_dmabuf *dmabuf)
964 {
965 	struct mdev_state *mdev_state = dmabuf->mdev_state;
966 	struct device *dev = mdev_dev(mdev_state->mdev);
967 	DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
968 	struct dma_buf *buf;
969 
970 	WARN_ON(!mutex_is_locked(&mdev_state->ops_lock));
971 
972 	if (!IS_ALIGNED(dmabuf->mode.offset, PAGE_SIZE)) {
973 		dev_info_ratelimited(dev, "%s: framebuffer not page-aligned\n",
974 				     __func__);
975 		return -EINVAL;
976 	}
977 
978 	exp_info.ops = &mbochs_dmabuf_ops;
979 	exp_info.size = dmabuf->mode.size;
980 	exp_info.priv = dmabuf;
981 
982 	buf = dma_buf_export(&exp_info);
983 	if (IS_ERR(buf)) {
984 		dev_info_ratelimited(dev, "%s: dma_buf_export failed: %ld\n",
985 				     __func__, PTR_ERR(buf));
986 		return PTR_ERR(buf);
987 	}
988 
989 	dmabuf->buf = buf;
990 	dev_dbg(dev, "%s: %d\n", __func__, dmabuf->id);
991 	return 0;
992 }
993 
994 static int mbochs_get_region_info(struct mdev_device *mdev,
995 				  struct vfio_region_info_ext *ext)
996 {
997 	struct vfio_region_info *region_info = &ext->base;
998 	struct mdev_state *mdev_state;
999 
1000 	mdev_state = mdev_get_drvdata(mdev);
1001 	if (!mdev_state)
1002 		return -EINVAL;
1003 
1004 	if (region_info->index >= MBOCHS_NUM_REGIONS)
1005 		return -EINVAL;
1006 
1007 	switch (region_info->index) {
1008 	case VFIO_PCI_CONFIG_REGION_INDEX:
1009 		region_info->offset = 0;
1010 		region_info->size   = MBOCHS_CONFIG_SPACE_SIZE;
1011 		region_info->flags  = (VFIO_REGION_INFO_FLAG_READ |
1012 				       VFIO_REGION_INFO_FLAG_WRITE);
1013 		break;
1014 	case VFIO_PCI_BAR0_REGION_INDEX:
1015 		region_info->offset = MBOCHS_MEMORY_BAR_OFFSET;
1016 		region_info->size   = mdev_state->memsize;
1017 		region_info->flags  = (VFIO_REGION_INFO_FLAG_READ  |
1018 				       VFIO_REGION_INFO_FLAG_WRITE |
1019 				       VFIO_REGION_INFO_FLAG_MMAP);
1020 		break;
1021 	case VFIO_PCI_BAR2_REGION_INDEX:
1022 		region_info->offset = MBOCHS_MMIO_BAR_OFFSET;
1023 		region_info->size   = MBOCHS_MMIO_BAR_SIZE;
1024 		region_info->flags  = (VFIO_REGION_INFO_FLAG_READ  |
1025 				       VFIO_REGION_INFO_FLAG_WRITE);
1026 		break;
1027 	case MBOCHS_EDID_REGION_INDEX:
1028 		ext->base.argsz = sizeof(*ext);
1029 		ext->base.offset = MBOCHS_EDID_OFFSET;
1030 		ext->base.size = MBOCHS_EDID_SIZE;
1031 		ext->base.flags = (VFIO_REGION_INFO_FLAG_READ  |
1032 				   VFIO_REGION_INFO_FLAG_WRITE |
1033 				   VFIO_REGION_INFO_FLAG_CAPS);
1034 		ext->base.cap_offset = offsetof(typeof(*ext), type);
1035 		ext->type.header.id = VFIO_REGION_INFO_CAP_TYPE;
1036 		ext->type.header.version = 1;
1037 		ext->type.header.next = 0;
1038 		ext->type.type = VFIO_REGION_TYPE_GFX;
1039 		ext->type.subtype = VFIO_REGION_SUBTYPE_GFX_EDID;
1040 		break;
1041 	default:
1042 		region_info->size   = 0;
1043 		region_info->offset = 0;
1044 		region_info->flags  = 0;
1045 	}
1046 
1047 	return 0;
1048 }
1049 
1050 static int mbochs_get_irq_info(struct mdev_device *mdev,
1051 			       struct vfio_irq_info *irq_info)
1052 {
1053 	irq_info->count = 0;
1054 	return 0;
1055 }
1056 
1057 static int mbochs_get_device_info(struct mdev_device *mdev,
1058 				  struct vfio_device_info *dev_info)
1059 {
1060 	dev_info->flags = VFIO_DEVICE_FLAGS_PCI;
1061 	dev_info->num_regions = MBOCHS_NUM_REGIONS;
1062 	dev_info->num_irqs = VFIO_PCI_NUM_IRQS;
1063 	return 0;
1064 }
1065 
1066 static int mbochs_query_gfx_plane(struct mdev_device *mdev,
1067 				  struct vfio_device_gfx_plane_info *plane)
1068 {
1069 	struct mdev_state *mdev_state = mdev_get_drvdata(mdev);
1070 	struct device *dev = mdev_dev(mdev);
1071 	struct mbochs_dmabuf *dmabuf;
1072 	struct mbochs_mode mode;
1073 	int ret;
1074 
1075 	if (plane->flags & VFIO_GFX_PLANE_TYPE_PROBE) {
1076 		if (plane->flags == (VFIO_GFX_PLANE_TYPE_PROBE |
1077 				     VFIO_GFX_PLANE_TYPE_DMABUF))
1078 			return 0;
1079 		return -EINVAL;
1080 	}
1081 
1082 	if (plane->flags != VFIO_GFX_PLANE_TYPE_DMABUF)
1083 		return -EINVAL;
1084 
1085 	plane->drm_format_mod = 0;
1086 	plane->x_pos	      = 0;
1087 	plane->y_pos	      = 0;
1088 	plane->x_hot	      = 0;
1089 	plane->y_hot	      = 0;
1090 
1091 	mutex_lock(&mdev_state->ops_lock);
1092 
1093 	ret = -EINVAL;
1094 	if (plane->drm_plane_type == DRM_PLANE_TYPE_PRIMARY)
1095 		ret = mbochs_check_framebuffer(mdev_state, &mode);
1096 	if (ret < 0) {
1097 		plane->drm_format     = 0;
1098 		plane->width	      = 0;
1099 		plane->height	      = 0;
1100 		plane->stride	      = 0;
1101 		plane->size	      = 0;
1102 		plane->dmabuf_id      = 0;
1103 		goto done;
1104 	}
1105 
1106 	dmabuf = mbochs_dmabuf_find_by_mode(mdev_state, &mode);
1107 	if (!dmabuf)
1108 		mbochs_dmabuf_alloc(mdev_state, &mode);
1109 	if (!dmabuf) {
1110 		mutex_unlock(&mdev_state->ops_lock);
1111 		return -ENOMEM;
1112 	}
1113 
1114 	plane->drm_format     = dmabuf->mode.drm_format;
1115 	plane->width	      = dmabuf->mode.width;
1116 	plane->height	      = dmabuf->mode.height;
1117 	plane->stride	      = dmabuf->mode.stride;
1118 	plane->size	      = dmabuf->mode.size;
1119 	plane->dmabuf_id      = dmabuf->id;
1120 
1121 done:
1122 	if (plane->drm_plane_type == DRM_PLANE_TYPE_PRIMARY &&
1123 	    mdev_state->active_id != plane->dmabuf_id) {
1124 		dev_dbg(dev, "%s: primary: %d => %d\n", __func__,
1125 			mdev_state->active_id, plane->dmabuf_id);
1126 		mdev_state->active_id = plane->dmabuf_id;
1127 	}
1128 	mutex_unlock(&mdev_state->ops_lock);
1129 	return 0;
1130 }
1131 
1132 static int mbochs_get_gfx_dmabuf(struct mdev_device *mdev,
1133 				 u32 id)
1134 {
1135 	struct mdev_state *mdev_state = mdev_get_drvdata(mdev);
1136 	struct mbochs_dmabuf *dmabuf;
1137 
1138 	mutex_lock(&mdev_state->ops_lock);
1139 
1140 	dmabuf = mbochs_dmabuf_find_by_id(mdev_state, id);
1141 	if (!dmabuf) {
1142 		mutex_unlock(&mdev_state->ops_lock);
1143 		return -ENOENT;
1144 	}
1145 
1146 	if (!dmabuf->buf)
1147 		mbochs_dmabuf_export(dmabuf);
1148 
1149 	mutex_unlock(&mdev_state->ops_lock);
1150 
1151 	if (!dmabuf->buf)
1152 		return -EINVAL;
1153 
1154 	return dma_buf_fd(dmabuf->buf, 0);
1155 }
1156 
1157 static long mbochs_ioctl(struct mdev_device *mdev, unsigned int cmd,
1158 			unsigned long arg)
1159 {
1160 	int ret = 0;
1161 	unsigned long minsz, outsz;
1162 
1163 	switch (cmd) {
1164 	case VFIO_DEVICE_GET_INFO:
1165 	{
1166 		struct vfio_device_info info;
1167 
1168 		minsz = offsetofend(struct vfio_device_info, num_irqs);
1169 
1170 		if (copy_from_user(&info, (void __user *)arg, minsz))
1171 			return -EFAULT;
1172 
1173 		if (info.argsz < minsz)
1174 			return -EINVAL;
1175 
1176 		ret = mbochs_get_device_info(mdev, &info);
1177 		if (ret)
1178 			return ret;
1179 
1180 		if (copy_to_user((void __user *)arg, &info, minsz))
1181 			return -EFAULT;
1182 
1183 		return 0;
1184 	}
1185 	case VFIO_DEVICE_GET_REGION_INFO:
1186 	{
1187 		struct vfio_region_info_ext info;
1188 
1189 		minsz = offsetofend(typeof(info), base.offset);
1190 
1191 		if (copy_from_user(&info, (void __user *)arg, minsz))
1192 			return -EFAULT;
1193 
1194 		outsz = info.base.argsz;
1195 		if (outsz < minsz)
1196 			return -EINVAL;
1197 		if (outsz > sizeof(info))
1198 			return -EINVAL;
1199 
1200 		ret = mbochs_get_region_info(mdev, &info);
1201 		if (ret)
1202 			return ret;
1203 
1204 		if (copy_to_user((void __user *)arg, &info, outsz))
1205 			return -EFAULT;
1206 
1207 		return 0;
1208 	}
1209 
1210 	case VFIO_DEVICE_GET_IRQ_INFO:
1211 	{
1212 		struct vfio_irq_info info;
1213 
1214 		minsz = offsetofend(struct vfio_irq_info, count);
1215 
1216 		if (copy_from_user(&info, (void __user *)arg, minsz))
1217 			return -EFAULT;
1218 
1219 		if ((info.argsz < minsz) ||
1220 		    (info.index >= VFIO_PCI_NUM_IRQS))
1221 			return -EINVAL;
1222 
1223 		ret = mbochs_get_irq_info(mdev, &info);
1224 		if (ret)
1225 			return ret;
1226 
1227 		if (copy_to_user((void __user *)arg, &info, minsz))
1228 			return -EFAULT;
1229 
1230 		return 0;
1231 	}
1232 
1233 	case VFIO_DEVICE_QUERY_GFX_PLANE:
1234 	{
1235 		struct vfio_device_gfx_plane_info plane;
1236 
1237 		minsz = offsetofend(struct vfio_device_gfx_plane_info,
1238 				    region_index);
1239 
1240 		if (copy_from_user(&plane, (void __user *)arg, minsz))
1241 			return -EFAULT;
1242 
1243 		if (plane.argsz < minsz)
1244 			return -EINVAL;
1245 
1246 		ret = mbochs_query_gfx_plane(mdev, &plane);
1247 		if (ret)
1248 			return ret;
1249 
1250 		if (copy_to_user((void __user *)arg, &plane, minsz))
1251 			return -EFAULT;
1252 
1253 		return 0;
1254 	}
1255 
1256 	case VFIO_DEVICE_GET_GFX_DMABUF:
1257 	{
1258 		u32 dmabuf_id;
1259 
1260 		if (get_user(dmabuf_id, (__u32 __user *)arg))
1261 			return -EFAULT;
1262 
1263 		return mbochs_get_gfx_dmabuf(mdev, dmabuf_id);
1264 	}
1265 
1266 	case VFIO_DEVICE_SET_IRQS:
1267 		return -EINVAL;
1268 
1269 	case VFIO_DEVICE_RESET:
1270 		return mbochs_reset(mdev);
1271 	}
1272 	return -ENOTTY;
1273 }
1274 
1275 static int mbochs_open(struct mdev_device *mdev)
1276 {
1277 	if (!try_module_get(THIS_MODULE))
1278 		return -ENODEV;
1279 
1280 	return 0;
1281 }
1282 
1283 static void mbochs_close(struct mdev_device *mdev)
1284 {
1285 	struct mdev_state *mdev_state = mdev_get_drvdata(mdev);
1286 	struct mbochs_dmabuf *dmabuf, *tmp;
1287 
1288 	mutex_lock(&mdev_state->ops_lock);
1289 
1290 	list_for_each_entry_safe(dmabuf, tmp, &mdev_state->dmabufs, next) {
1291 		list_del(&dmabuf->next);
1292 		if (dmabuf->buf) {
1293 			/* free in mbochs_release_dmabuf() */
1294 			dmabuf->unlinked = true;
1295 		} else {
1296 			kfree(dmabuf);
1297 		}
1298 	}
1299 	mbochs_put_pages(mdev_state);
1300 
1301 	mutex_unlock(&mdev_state->ops_lock);
1302 	module_put(THIS_MODULE);
1303 }
1304 
1305 static ssize_t
1306 memory_show(struct device *dev, struct device_attribute *attr,
1307 	    char *buf)
1308 {
1309 	struct mdev_device *mdev = mdev_from_dev(dev);
1310 	struct mdev_state *mdev_state = mdev_get_drvdata(mdev);
1311 
1312 	return sprintf(buf, "%d MB\n", mdev_state->type->mbytes);
1313 }
1314 static DEVICE_ATTR_RO(memory);
1315 
1316 static struct attribute *mdev_dev_attrs[] = {
1317 	&dev_attr_memory.attr,
1318 	NULL,
1319 };
1320 
1321 static const struct attribute_group mdev_dev_group = {
1322 	.name  = "vendor",
1323 	.attrs = mdev_dev_attrs,
1324 };
1325 
1326 static const struct attribute_group *mdev_dev_groups[] = {
1327 	&mdev_dev_group,
1328 	NULL,
1329 };
1330 
1331 static ssize_t name_show(struct mdev_type *mtype,
1332 			 struct mdev_type_attribute *attr, char *buf)
1333 {
1334 	const struct mbochs_type *type =
1335 		&mbochs_types[mtype_get_type_group_id(mtype)];
1336 
1337 	return sprintf(buf, "%s\n", type->name);
1338 }
1339 static MDEV_TYPE_ATTR_RO(name);
1340 
1341 static ssize_t description_show(struct mdev_type *mtype,
1342 				struct mdev_type_attribute *attr, char *buf)
1343 {
1344 	const struct mbochs_type *type =
1345 		&mbochs_types[mtype_get_type_group_id(mtype)];
1346 
1347 	return sprintf(buf, "virtual display, %d MB video memory\n",
1348 		       type ? type->mbytes  : 0);
1349 }
1350 static MDEV_TYPE_ATTR_RO(description);
1351 
1352 static ssize_t available_instances_show(struct mdev_type *mtype,
1353 					struct mdev_type_attribute *attr,
1354 					char *buf)
1355 {
1356 	const struct mbochs_type *type =
1357 		&mbochs_types[mtype_get_type_group_id(mtype)];
1358 	int count = (max_mbytes - mbochs_used_mbytes) / type->mbytes;
1359 
1360 	return sprintf(buf, "%d\n", count);
1361 }
1362 static MDEV_TYPE_ATTR_RO(available_instances);
1363 
1364 static ssize_t device_api_show(struct mdev_type *mtype,
1365 			       struct mdev_type_attribute *attr, char *buf)
1366 {
1367 	return sprintf(buf, "%s\n", VFIO_DEVICE_API_PCI_STRING);
1368 }
1369 static MDEV_TYPE_ATTR_RO(device_api);
1370 
1371 static struct attribute *mdev_types_attrs[] = {
1372 	&mdev_type_attr_name.attr,
1373 	&mdev_type_attr_description.attr,
1374 	&mdev_type_attr_device_api.attr,
1375 	&mdev_type_attr_available_instances.attr,
1376 	NULL,
1377 };
1378 
1379 static struct attribute_group mdev_type_group1 = {
1380 	.name  = MBOCHS_TYPE_1,
1381 	.attrs = mdev_types_attrs,
1382 };
1383 
1384 static struct attribute_group mdev_type_group2 = {
1385 	.name  = MBOCHS_TYPE_2,
1386 	.attrs = mdev_types_attrs,
1387 };
1388 
1389 static struct attribute_group mdev_type_group3 = {
1390 	.name  = MBOCHS_TYPE_3,
1391 	.attrs = mdev_types_attrs,
1392 };
1393 
1394 static struct attribute_group *mdev_type_groups[] = {
1395 	&mdev_type_group1,
1396 	&mdev_type_group2,
1397 	&mdev_type_group3,
1398 	NULL,
1399 };
1400 
1401 static const struct mdev_parent_ops mdev_fops = {
1402 	.owner			= THIS_MODULE,
1403 	.mdev_attr_groups	= mdev_dev_groups,
1404 	.supported_type_groups	= mdev_type_groups,
1405 	.create			= mbochs_create,
1406 	.remove			= mbochs_remove,
1407 	.open			= mbochs_open,
1408 	.release		= mbochs_close,
1409 	.read			= mbochs_read,
1410 	.write			= mbochs_write,
1411 	.ioctl			= mbochs_ioctl,
1412 	.mmap			= mbochs_mmap,
1413 };
1414 
1415 static const struct file_operations vd_fops = {
1416 	.owner		= THIS_MODULE,
1417 };
1418 
1419 static void mbochs_device_release(struct device *dev)
1420 {
1421 	/* nothing */
1422 }
1423 
1424 static int __init mbochs_dev_init(void)
1425 {
1426 	int ret = 0;
1427 
1428 	ret = alloc_chrdev_region(&mbochs_devt, 0, MINORMASK + 1, MBOCHS_NAME);
1429 	if (ret < 0) {
1430 		pr_err("Error: failed to register mbochs_dev, err: %d\n", ret);
1431 		return ret;
1432 	}
1433 	cdev_init(&mbochs_cdev, &vd_fops);
1434 	cdev_add(&mbochs_cdev, mbochs_devt, MINORMASK + 1);
1435 	pr_info("%s: major %d\n", __func__, MAJOR(mbochs_devt));
1436 
1437 	mbochs_class = class_create(THIS_MODULE, MBOCHS_CLASS_NAME);
1438 	if (IS_ERR(mbochs_class)) {
1439 		pr_err("Error: failed to register mbochs_dev class\n");
1440 		ret = PTR_ERR(mbochs_class);
1441 		goto failed1;
1442 	}
1443 	mbochs_dev.class = mbochs_class;
1444 	mbochs_dev.release = mbochs_device_release;
1445 	dev_set_name(&mbochs_dev, "%s", MBOCHS_NAME);
1446 
1447 	ret = device_register(&mbochs_dev);
1448 	if (ret)
1449 		goto failed2;
1450 
1451 	ret = mdev_register_device(&mbochs_dev, &mdev_fops);
1452 	if (ret)
1453 		goto failed3;
1454 
1455 	return 0;
1456 
1457 failed3:
1458 	device_unregister(&mbochs_dev);
1459 failed2:
1460 	class_destroy(mbochs_class);
1461 failed1:
1462 	cdev_del(&mbochs_cdev);
1463 	unregister_chrdev_region(mbochs_devt, MINORMASK + 1);
1464 	return ret;
1465 }
1466 
1467 static void __exit mbochs_dev_exit(void)
1468 {
1469 	mbochs_dev.bus = NULL;
1470 	mdev_unregister_device(&mbochs_dev);
1471 
1472 	device_unregister(&mbochs_dev);
1473 	cdev_del(&mbochs_cdev);
1474 	unregister_chrdev_region(mbochs_devt, MINORMASK + 1);
1475 	class_destroy(mbochs_class);
1476 	mbochs_class = NULL;
1477 }
1478 
1479 module_init(mbochs_dev_init)
1480 module_exit(mbochs_dev_exit)
1481