xref: /openbmc/linux/samples/vfio-mdev/mbochs.c (revision f3956ebb)
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 atomic_t mbochs_avail_mbytes;
133 static const struct vfio_device_ops mbochs_dev_ops;
134 
135 struct vfio_region_info_ext {
136 	struct vfio_region_info          base;
137 	struct vfio_region_info_cap_type type;
138 };
139 
140 struct mbochs_mode {
141 	u32 drm_format;
142 	u32 bytepp;
143 	u32 width;
144 	u32 height;
145 	u32 stride;
146 	u32 __pad;
147 	u64 offset;
148 	u64 size;
149 };
150 
151 struct mbochs_dmabuf {
152 	struct mbochs_mode mode;
153 	u32 id;
154 	struct page **pages;
155 	pgoff_t pagecount;
156 	struct dma_buf *buf;
157 	struct mdev_state *mdev_state;
158 	struct list_head next;
159 	bool unlinked;
160 };
161 
162 /* State of each mdev device */
163 struct mdev_state {
164 	struct vfio_device vdev;
165 	u8 *vconfig;
166 	u64 bar_mask[3];
167 	u32 memory_bar_mask;
168 	struct mutex ops_lock;
169 	struct mdev_device *mdev;
170 
171 	const struct mbochs_type *type;
172 	u16 vbe[VBE_DISPI_INDEX_COUNT];
173 	u64 memsize;
174 	struct page **pages;
175 	pgoff_t pagecount;
176 	struct vfio_region_gfx_edid edid_regs;
177 	u8 edid_blob[0x400];
178 
179 	struct list_head dmabufs;
180 	u32 active_id;
181 	u32 next_id;
182 };
183 
184 static const char *vbe_name_list[VBE_DISPI_INDEX_COUNT] = {
185 	[VBE_DISPI_INDEX_ID]               = "id",
186 	[VBE_DISPI_INDEX_XRES]             = "xres",
187 	[VBE_DISPI_INDEX_YRES]             = "yres",
188 	[VBE_DISPI_INDEX_BPP]              = "bpp",
189 	[VBE_DISPI_INDEX_ENABLE]           = "enable",
190 	[VBE_DISPI_INDEX_BANK]             = "bank",
191 	[VBE_DISPI_INDEX_VIRT_WIDTH]       = "virt-width",
192 	[VBE_DISPI_INDEX_VIRT_HEIGHT]      = "virt-height",
193 	[VBE_DISPI_INDEX_X_OFFSET]         = "x-offset",
194 	[VBE_DISPI_INDEX_Y_OFFSET]         = "y-offset",
195 	[VBE_DISPI_INDEX_VIDEO_MEMORY_64K] = "video-mem",
196 };
197 
198 static const char *vbe_name(u32 index)
199 {
200 	if (index < ARRAY_SIZE(vbe_name_list))
201 		return vbe_name_list[index];
202 	return "(invalid)";
203 }
204 
205 static struct page *__mbochs_get_page(struct mdev_state *mdev_state,
206 				      pgoff_t pgoff);
207 static struct page *mbochs_get_page(struct mdev_state *mdev_state,
208 				    pgoff_t pgoff);
209 
210 static void mbochs_create_config_space(struct mdev_state *mdev_state)
211 {
212 	STORE_LE16((u16 *) &mdev_state->vconfig[PCI_VENDOR_ID],
213 		   0x1234);
214 	STORE_LE16((u16 *) &mdev_state->vconfig[PCI_DEVICE_ID],
215 		   0x1111);
216 	STORE_LE16((u16 *) &mdev_state->vconfig[PCI_SUBSYSTEM_VENDOR_ID],
217 		   PCI_SUBVENDOR_ID_REDHAT_QUMRANET);
218 	STORE_LE16((u16 *) &mdev_state->vconfig[PCI_SUBSYSTEM_ID],
219 		   PCI_SUBDEVICE_ID_QEMU);
220 
221 	STORE_LE16((u16 *) &mdev_state->vconfig[PCI_COMMAND],
222 		   PCI_COMMAND_IO | PCI_COMMAND_MEMORY);
223 	STORE_LE16((u16 *) &mdev_state->vconfig[PCI_CLASS_DEVICE],
224 		   PCI_CLASS_DISPLAY_OTHER);
225 	mdev_state->vconfig[PCI_CLASS_REVISION] =  0x01;
226 
227 	STORE_LE32((u32 *) &mdev_state->vconfig[PCI_BASE_ADDRESS_0],
228 		   PCI_BASE_ADDRESS_SPACE_MEMORY |
229 		   PCI_BASE_ADDRESS_MEM_TYPE_32	 |
230 		   PCI_BASE_ADDRESS_MEM_PREFETCH);
231 	mdev_state->bar_mask[0] = ~(mdev_state->memsize) + 1;
232 
233 	STORE_LE32((u32 *) &mdev_state->vconfig[PCI_BASE_ADDRESS_2],
234 		   PCI_BASE_ADDRESS_SPACE_MEMORY |
235 		   PCI_BASE_ADDRESS_MEM_TYPE_32);
236 	mdev_state->bar_mask[2] = ~(MBOCHS_MMIO_BAR_SIZE) + 1;
237 }
238 
239 static int mbochs_check_framebuffer(struct mdev_state *mdev_state,
240 				    struct mbochs_mode *mode)
241 {
242 	struct device *dev = mdev_dev(mdev_state->mdev);
243 	u16 *vbe = mdev_state->vbe;
244 	u32 virt_width;
245 
246 	WARN_ON(!mutex_is_locked(&mdev_state->ops_lock));
247 
248 	if (!(vbe[VBE_DISPI_INDEX_ENABLE] & VBE_DISPI_ENABLED))
249 		goto nofb;
250 
251 	memset(mode, 0, sizeof(*mode));
252 	switch (vbe[VBE_DISPI_INDEX_BPP]) {
253 	case 32:
254 		mode->drm_format = DRM_FORMAT_XRGB8888;
255 		mode->bytepp = 4;
256 		break;
257 	default:
258 		dev_info_ratelimited(dev, "%s: bpp %d not supported\n",
259 				     __func__, vbe[VBE_DISPI_INDEX_BPP]);
260 		goto nofb;
261 	}
262 
263 	mode->width  = vbe[VBE_DISPI_INDEX_XRES];
264 	mode->height = vbe[VBE_DISPI_INDEX_YRES];
265 	virt_width  = vbe[VBE_DISPI_INDEX_VIRT_WIDTH];
266 	if (virt_width < mode->width)
267 		virt_width = mode->width;
268 	mode->stride = virt_width * mode->bytepp;
269 	mode->size   = (u64)mode->stride * mode->height;
270 	mode->offset = ((u64)vbe[VBE_DISPI_INDEX_X_OFFSET] * mode->bytepp +
271 		       (u64)vbe[VBE_DISPI_INDEX_Y_OFFSET] * mode->stride);
272 
273 	if (mode->width < 64 || mode->height < 64) {
274 		dev_info_ratelimited(dev, "%s: invalid resolution %dx%d\n",
275 				     __func__, mode->width, mode->height);
276 		goto nofb;
277 	}
278 	if (mode->offset + mode->size > mdev_state->memsize) {
279 		dev_info_ratelimited(dev, "%s: framebuffer memory overflow\n",
280 				     __func__);
281 		goto nofb;
282 	}
283 
284 	return 0;
285 
286 nofb:
287 	memset(mode, 0, sizeof(*mode));
288 	return -EINVAL;
289 }
290 
291 static bool mbochs_modes_equal(struct mbochs_mode *mode1,
292 			       struct mbochs_mode *mode2)
293 {
294 	return memcmp(mode1, mode2, sizeof(struct mbochs_mode)) == 0;
295 }
296 
297 static void handle_pci_cfg_write(struct mdev_state *mdev_state, u16 offset,
298 				 char *buf, u32 count)
299 {
300 	struct device *dev = mdev_dev(mdev_state->mdev);
301 	int index = (offset - PCI_BASE_ADDRESS_0) / 0x04;
302 	u32 cfg_addr;
303 
304 	switch (offset) {
305 	case PCI_BASE_ADDRESS_0:
306 	case PCI_BASE_ADDRESS_2:
307 		cfg_addr = *(u32 *)buf;
308 
309 		if (cfg_addr == 0xffffffff) {
310 			cfg_addr = (cfg_addr & mdev_state->bar_mask[index]);
311 		} else {
312 			cfg_addr &= PCI_BASE_ADDRESS_MEM_MASK;
313 			if (cfg_addr)
314 				dev_info(dev, "BAR #%d @ 0x%x\n",
315 					 index, cfg_addr);
316 		}
317 
318 		cfg_addr |= (mdev_state->vconfig[offset] &
319 			     ~PCI_BASE_ADDRESS_MEM_MASK);
320 		STORE_LE32(&mdev_state->vconfig[offset], cfg_addr);
321 		break;
322 	}
323 }
324 
325 static void handle_mmio_write(struct mdev_state *mdev_state, u16 offset,
326 			      char *buf, u32 count)
327 {
328 	struct device *dev = mdev_dev(mdev_state->mdev);
329 	int index;
330 	u16 reg16;
331 
332 	switch (offset) {
333 	case 0x400 ... 0x41f: /* vga ioports remapped */
334 		goto unhandled;
335 	case 0x500 ... 0x515: /* bochs dispi interface */
336 		if (count != 2)
337 			goto unhandled;
338 		index = (offset - 0x500) / 2;
339 		reg16 = *(u16 *)buf;
340 		if (index < ARRAY_SIZE(mdev_state->vbe))
341 			mdev_state->vbe[index] = reg16;
342 		dev_dbg(dev, "%s: vbe write %d = %d (%s)\n",
343 			__func__, index, reg16, vbe_name(index));
344 		break;
345 	case 0x600 ... 0x607: /* qemu extended regs */
346 		goto unhandled;
347 	default:
348 unhandled:
349 		dev_dbg(dev, "%s: @0x%03x, count %d (unhandled)\n",
350 			__func__, offset, count);
351 		break;
352 	}
353 }
354 
355 static void handle_mmio_read(struct mdev_state *mdev_state, u16 offset,
356 			     char *buf, u32 count)
357 {
358 	struct device *dev = mdev_dev(mdev_state->mdev);
359 	struct vfio_region_gfx_edid *edid;
360 	u16 reg16 = 0;
361 	int index;
362 
363 	switch (offset) {
364 	case 0x000 ... 0x3ff: /* edid block */
365 		edid = &mdev_state->edid_regs;
366 		if (edid->link_state != VFIO_DEVICE_GFX_LINK_STATE_UP ||
367 		    offset >= edid->edid_size) {
368 			memset(buf, 0, count);
369 			break;
370 		}
371 		memcpy(buf, mdev_state->edid_blob + offset, count);
372 		break;
373 	case 0x500 ... 0x515: /* bochs dispi interface */
374 		if (count != 2)
375 			goto unhandled;
376 		index = (offset - 0x500) / 2;
377 		if (index < ARRAY_SIZE(mdev_state->vbe))
378 			reg16 = mdev_state->vbe[index];
379 		dev_dbg(dev, "%s: vbe read %d = %d (%s)\n",
380 			__func__, index, reg16, vbe_name(index));
381 		*(u16 *)buf = reg16;
382 		break;
383 	default:
384 unhandled:
385 		dev_dbg(dev, "%s: @0x%03x, count %d (unhandled)\n",
386 			__func__, offset, count);
387 		memset(buf, 0, count);
388 		break;
389 	}
390 }
391 
392 static void handle_edid_regs(struct mdev_state *mdev_state, u16 offset,
393 			     char *buf, u32 count, bool is_write)
394 {
395 	char *regs = (void *)&mdev_state->edid_regs;
396 
397 	if (offset + count > sizeof(mdev_state->edid_regs))
398 		return;
399 	if (count != 4)
400 		return;
401 	if (offset % 4)
402 		return;
403 
404 	if (is_write) {
405 		switch (offset) {
406 		case offsetof(struct vfio_region_gfx_edid, link_state):
407 		case offsetof(struct vfio_region_gfx_edid, edid_size):
408 			memcpy(regs + offset, buf, count);
409 			break;
410 		default:
411 			/* read-only regs */
412 			break;
413 		}
414 	} else {
415 		memcpy(buf, regs + offset, count);
416 	}
417 }
418 
419 static void handle_edid_blob(struct mdev_state *mdev_state, u16 offset,
420 			     char *buf, u32 count, bool is_write)
421 {
422 	if (offset + count > mdev_state->edid_regs.edid_max_size)
423 		return;
424 	if (is_write)
425 		memcpy(mdev_state->edid_blob + offset, buf, count);
426 	else
427 		memcpy(buf, mdev_state->edid_blob + offset, count);
428 }
429 
430 static ssize_t mdev_access(struct mdev_state *mdev_state, char *buf,
431 			   size_t count, loff_t pos, bool is_write)
432 {
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(mdev_state->vdev.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_state *mdev_state)
497 {
498 	u32 size64k = mdev_state->memsize / (64 * 1024);
499 	int i;
500 
501 	for (i = 0; i < ARRAY_SIZE(mdev_state->vbe); i++)
502 		mdev_state->vbe[i] = 0;
503 	mdev_state->vbe[VBE_DISPI_INDEX_ID] = VBE_DISPI_ID5;
504 	mdev_state->vbe[VBE_DISPI_INDEX_VIDEO_MEMORY_64K] = size64k;
505 	return 0;
506 }
507 
508 static int mbochs_probe(struct mdev_device *mdev)
509 {
510 	int avail_mbytes = atomic_read(&mbochs_avail_mbytes);
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 	int ret = -ENOMEM;
516 
517 	do {
518 		if (avail_mbytes < type->mbytes)
519 			return -ENOSPC;
520 	} while (!atomic_try_cmpxchg(&mbochs_avail_mbytes, &avail_mbytes,
521 				     avail_mbytes - type->mbytes));
522 
523 	mdev_state = kzalloc(sizeof(struct mdev_state), GFP_KERNEL);
524 	if (mdev_state == NULL)
525 		goto err_avail;
526 	vfio_init_group_dev(&mdev_state->vdev, &mdev->dev, &mbochs_dev_ops);
527 
528 	mdev_state->vconfig = kzalloc(MBOCHS_CONFIG_SPACE_SIZE, GFP_KERNEL);
529 	if (mdev_state->vconfig == NULL)
530 		goto err_mem;
531 
532 	mdev_state->memsize = type->mbytes * 1024 * 1024;
533 	mdev_state->pagecount = mdev_state->memsize >> PAGE_SHIFT;
534 	mdev_state->pages = kcalloc(mdev_state->pagecount,
535 				    sizeof(struct page *),
536 				    GFP_KERNEL);
537 	if (!mdev_state->pages)
538 		goto err_mem;
539 
540 	dev_info(dev, "%s: %s, %d MB, %ld pages\n", __func__,
541 		 type->name, type->mbytes, mdev_state->pagecount);
542 
543 	mutex_init(&mdev_state->ops_lock);
544 	mdev_state->mdev = mdev;
545 	INIT_LIST_HEAD(&mdev_state->dmabufs);
546 	mdev_state->next_id = 1;
547 
548 	mdev_state->type = type;
549 	mdev_state->edid_regs.max_xres = type->max_x;
550 	mdev_state->edid_regs.max_yres = type->max_y;
551 	mdev_state->edid_regs.edid_offset = MBOCHS_EDID_BLOB_OFFSET;
552 	mdev_state->edid_regs.edid_max_size = sizeof(mdev_state->edid_blob);
553 	mbochs_create_config_space(mdev_state);
554 	mbochs_reset(mdev_state);
555 
556 	ret = vfio_register_group_dev(&mdev_state->vdev);
557 	if (ret)
558 		goto err_mem;
559 	dev_set_drvdata(&mdev->dev, mdev_state);
560 	return 0;
561 err_mem:
562 	vfio_uninit_group_dev(&mdev_state->vdev);
563 	kfree(mdev_state->pages);
564 	kfree(mdev_state->vconfig);
565 	kfree(mdev_state);
566 err_avail:
567 	atomic_add(type->mbytes, &mbochs_avail_mbytes);
568 	return ret;
569 }
570 
571 static void mbochs_remove(struct mdev_device *mdev)
572 {
573 	struct mdev_state *mdev_state = dev_get_drvdata(&mdev->dev);
574 
575 	vfio_unregister_group_dev(&mdev_state->vdev);
576 	vfio_uninit_group_dev(&mdev_state->vdev);
577 	atomic_add(mdev_state->type->mbytes, &mbochs_avail_mbytes);
578 	kfree(mdev_state->pages);
579 	kfree(mdev_state->vconfig);
580 	kfree(mdev_state);
581 }
582 
583 static ssize_t mbochs_read(struct vfio_device *vdev, char __user *buf,
584 			   size_t count, loff_t *ppos)
585 {
586 	struct mdev_state *mdev_state =
587 		container_of(vdev, struct mdev_state, vdev);
588 	unsigned int done = 0;
589 	int ret;
590 
591 	while (count) {
592 		size_t filled;
593 
594 		if (count >= 4 && !(*ppos % 4)) {
595 			u32 val;
596 
597 			ret =  mdev_access(mdev_state, (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 = 4;
606 		} else if (count >= 2 && !(*ppos % 2)) {
607 			u16 val;
608 
609 			ret = mdev_access(mdev_state, (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 = 2;
618 		} else {
619 			u8 val;
620 
621 			ret = mdev_access(mdev_state, (char *)&val, sizeof(val),
622 					  *ppos, false);
623 			if (ret <= 0)
624 				goto read_err;
625 
626 			if (copy_to_user(buf, &val, sizeof(val)))
627 				goto read_err;
628 
629 			filled = 1;
630 		}
631 
632 		count -= filled;
633 		done += filled;
634 		*ppos += filled;
635 		buf += filled;
636 	}
637 
638 	return done;
639 
640 read_err:
641 	return -EFAULT;
642 }
643 
644 static ssize_t mbochs_write(struct vfio_device *vdev, const char __user *buf,
645 			    size_t count, loff_t *ppos)
646 {
647 	struct mdev_state *mdev_state =
648 		container_of(vdev, struct mdev_state, vdev);
649 	unsigned int done = 0;
650 	int ret;
651 
652 	while (count) {
653 		size_t filled;
654 
655 		if (count >= 4 && !(*ppos % 4)) {
656 			u32 val;
657 
658 			if (copy_from_user(&val, buf, sizeof(val)))
659 				goto write_err;
660 
661 			ret = mdev_access(mdev_state, (char *)&val, sizeof(val),
662 					  *ppos, true);
663 			if (ret <= 0)
664 				goto write_err;
665 
666 			filled = 4;
667 		} else if (count >= 2 && !(*ppos % 2)) {
668 			u16 val;
669 
670 			if (copy_from_user(&val, buf, sizeof(val)))
671 				goto write_err;
672 
673 			ret = mdev_access(mdev_state, (char *)&val, sizeof(val),
674 					  *ppos, true);
675 			if (ret <= 0)
676 				goto write_err;
677 
678 			filled = 2;
679 		} else {
680 			u8 val;
681 
682 			if (copy_from_user(&val, buf, sizeof(val)))
683 				goto write_err;
684 
685 			ret = mdev_access(mdev_state, (char *)&val, sizeof(val),
686 					  *ppos, true);
687 			if (ret <= 0)
688 				goto write_err;
689 
690 			filled = 1;
691 		}
692 		count -= filled;
693 		done += filled;
694 		*ppos += filled;
695 		buf += filled;
696 	}
697 
698 	return done;
699 write_err:
700 	return -EFAULT;
701 }
702 
703 static struct page *__mbochs_get_page(struct mdev_state *mdev_state,
704 				      pgoff_t pgoff)
705 {
706 	WARN_ON(!mutex_is_locked(&mdev_state->ops_lock));
707 
708 	if (!mdev_state->pages[pgoff]) {
709 		mdev_state->pages[pgoff] =
710 			alloc_pages(GFP_HIGHUSER | __GFP_ZERO, 0);
711 		if (!mdev_state->pages[pgoff])
712 			return NULL;
713 	}
714 
715 	get_page(mdev_state->pages[pgoff]);
716 	return mdev_state->pages[pgoff];
717 }
718 
719 static struct page *mbochs_get_page(struct mdev_state *mdev_state,
720 				    pgoff_t pgoff)
721 {
722 	struct page *page;
723 
724 	if (WARN_ON(pgoff >= mdev_state->pagecount))
725 		return NULL;
726 
727 	mutex_lock(&mdev_state->ops_lock);
728 	page = __mbochs_get_page(mdev_state, pgoff);
729 	mutex_unlock(&mdev_state->ops_lock);
730 
731 	return page;
732 }
733 
734 static void mbochs_put_pages(struct mdev_state *mdev_state)
735 {
736 	struct device *dev = mdev_dev(mdev_state->mdev);
737 	int i, count = 0;
738 
739 	WARN_ON(!mutex_is_locked(&mdev_state->ops_lock));
740 
741 	for (i = 0; i < mdev_state->pagecount; i++) {
742 		if (!mdev_state->pages[i])
743 			continue;
744 		put_page(mdev_state->pages[i]);
745 		mdev_state->pages[i] = NULL;
746 		count++;
747 	}
748 	dev_dbg(dev, "%s: %d pages released\n", __func__, count);
749 }
750 
751 static vm_fault_t mbochs_region_vm_fault(struct vm_fault *vmf)
752 {
753 	struct vm_area_struct *vma = vmf->vma;
754 	struct mdev_state *mdev_state = vma->vm_private_data;
755 	pgoff_t page_offset = (vmf->address - vma->vm_start) >> PAGE_SHIFT;
756 
757 	if (page_offset >= mdev_state->pagecount)
758 		return VM_FAULT_SIGBUS;
759 
760 	vmf->page = mbochs_get_page(mdev_state, page_offset);
761 	if (!vmf->page)
762 		return VM_FAULT_SIGBUS;
763 
764 	return 0;
765 }
766 
767 static const struct vm_operations_struct mbochs_region_vm_ops = {
768 	.fault = mbochs_region_vm_fault,
769 };
770 
771 static int mbochs_mmap(struct vfio_device *vdev, struct vm_area_struct *vma)
772 {
773 	struct mdev_state *mdev_state =
774 		container_of(vdev, struct mdev_state, vdev);
775 
776 	if (vma->vm_pgoff != MBOCHS_MEMORY_BAR_OFFSET >> PAGE_SHIFT)
777 		return -EINVAL;
778 	if (vma->vm_end < vma->vm_start)
779 		return -EINVAL;
780 	if (vma->vm_end - vma->vm_start > mdev_state->memsize)
781 		return -EINVAL;
782 	if ((vma->vm_flags & VM_SHARED) == 0)
783 		return -EINVAL;
784 
785 	vma->vm_ops = &mbochs_region_vm_ops;
786 	vma->vm_private_data = mdev_state;
787 	return 0;
788 }
789 
790 static vm_fault_t mbochs_dmabuf_vm_fault(struct vm_fault *vmf)
791 {
792 	struct vm_area_struct *vma = vmf->vma;
793 	struct mbochs_dmabuf *dmabuf = vma->vm_private_data;
794 
795 	if (WARN_ON(vmf->pgoff >= dmabuf->pagecount))
796 		return VM_FAULT_SIGBUS;
797 
798 	vmf->page = dmabuf->pages[vmf->pgoff];
799 	get_page(vmf->page);
800 	return 0;
801 }
802 
803 static const struct vm_operations_struct mbochs_dmabuf_vm_ops = {
804 	.fault = mbochs_dmabuf_vm_fault,
805 };
806 
807 static int mbochs_mmap_dmabuf(struct dma_buf *buf, struct vm_area_struct *vma)
808 {
809 	struct mbochs_dmabuf *dmabuf = buf->priv;
810 	struct device *dev = mdev_dev(dmabuf->mdev_state->mdev);
811 
812 	dev_dbg(dev, "%s: %d\n", __func__, dmabuf->id);
813 
814 	if ((vma->vm_flags & VM_SHARED) == 0)
815 		return -EINVAL;
816 
817 	vma->vm_ops = &mbochs_dmabuf_vm_ops;
818 	vma->vm_private_data = dmabuf;
819 	return 0;
820 }
821 
822 static void mbochs_print_dmabuf(struct mbochs_dmabuf *dmabuf,
823 				const char *prefix)
824 {
825 	struct device *dev = mdev_dev(dmabuf->mdev_state->mdev);
826 	u32 fourcc = dmabuf->mode.drm_format;
827 
828 	dev_dbg(dev, "%s/%d: %c%c%c%c, %dx%d, stride %d, off 0x%llx, size 0x%llx, pages %ld\n",
829 		prefix, dmabuf->id,
830 		fourcc ? ((fourcc >>  0) & 0xff) : '-',
831 		fourcc ? ((fourcc >>  8) & 0xff) : '-',
832 		fourcc ? ((fourcc >> 16) & 0xff) : '-',
833 		fourcc ? ((fourcc >> 24) & 0xff) : '-',
834 		dmabuf->mode.width, dmabuf->mode.height, dmabuf->mode.stride,
835 		dmabuf->mode.offset, dmabuf->mode.size, dmabuf->pagecount);
836 }
837 
838 static struct sg_table *mbochs_map_dmabuf(struct dma_buf_attachment *at,
839 					  enum dma_data_direction direction)
840 {
841 	struct mbochs_dmabuf *dmabuf = at->dmabuf->priv;
842 	struct device *dev = mdev_dev(dmabuf->mdev_state->mdev);
843 	struct sg_table *sg;
844 
845 	dev_dbg(dev, "%s: %d\n", __func__, dmabuf->id);
846 
847 	sg = kzalloc(sizeof(*sg), GFP_KERNEL);
848 	if (!sg)
849 		goto err1;
850 	if (sg_alloc_table_from_pages(sg, dmabuf->pages, dmabuf->pagecount,
851 				      0, dmabuf->mode.size, GFP_KERNEL) < 0)
852 		goto err2;
853 	if (dma_map_sgtable(at->dev, sg, direction, 0))
854 		goto err3;
855 
856 	return sg;
857 
858 err3:
859 	sg_free_table(sg);
860 err2:
861 	kfree(sg);
862 err1:
863 	return ERR_PTR(-ENOMEM);
864 }
865 
866 static void mbochs_unmap_dmabuf(struct dma_buf_attachment *at,
867 				struct sg_table *sg,
868 				enum dma_data_direction direction)
869 {
870 	struct mbochs_dmabuf *dmabuf = at->dmabuf->priv;
871 	struct device *dev = mdev_dev(dmabuf->mdev_state->mdev);
872 
873 	dev_dbg(dev, "%s: %d\n", __func__, dmabuf->id);
874 
875 	dma_unmap_sgtable(at->dev, sg, direction, 0);
876 	sg_free_table(sg);
877 	kfree(sg);
878 }
879 
880 static void mbochs_release_dmabuf(struct dma_buf *buf)
881 {
882 	struct mbochs_dmabuf *dmabuf = buf->priv;
883 	struct mdev_state *mdev_state = dmabuf->mdev_state;
884 	struct device *dev = mdev_dev(mdev_state->mdev);
885 	pgoff_t pg;
886 
887 	dev_dbg(dev, "%s: %d\n", __func__, dmabuf->id);
888 
889 	for (pg = 0; pg < dmabuf->pagecount; pg++)
890 		put_page(dmabuf->pages[pg]);
891 
892 	mutex_lock(&mdev_state->ops_lock);
893 	dmabuf->buf = NULL;
894 	if (dmabuf->unlinked)
895 		kfree(dmabuf);
896 	mutex_unlock(&mdev_state->ops_lock);
897 }
898 
899 static struct dma_buf_ops mbochs_dmabuf_ops = {
900 	.map_dma_buf	  = mbochs_map_dmabuf,
901 	.unmap_dma_buf	  = mbochs_unmap_dmabuf,
902 	.release	  = mbochs_release_dmabuf,
903 	.mmap		  = mbochs_mmap_dmabuf,
904 };
905 
906 static struct mbochs_dmabuf *mbochs_dmabuf_alloc(struct mdev_state *mdev_state,
907 						 struct mbochs_mode *mode)
908 {
909 	struct mbochs_dmabuf *dmabuf;
910 	pgoff_t page_offset, pg;
911 
912 	WARN_ON(!mutex_is_locked(&mdev_state->ops_lock));
913 
914 	dmabuf = kzalloc(sizeof(struct mbochs_dmabuf), GFP_KERNEL);
915 	if (!dmabuf)
916 		return NULL;
917 
918 	dmabuf->mode = *mode;
919 	dmabuf->id = mdev_state->next_id++;
920 	dmabuf->pagecount = DIV_ROUND_UP(mode->size, PAGE_SIZE);
921 	dmabuf->pages = kcalloc(dmabuf->pagecount, sizeof(struct page *),
922 				GFP_KERNEL);
923 	if (!dmabuf->pages)
924 		goto err_free_dmabuf;
925 
926 	page_offset = dmabuf->mode.offset >> PAGE_SHIFT;
927 	for (pg = 0; pg < dmabuf->pagecount; pg++) {
928 		dmabuf->pages[pg] = __mbochs_get_page(mdev_state,
929 						      page_offset + pg);
930 		if (!dmabuf->pages[pg])
931 			goto err_free_pages;
932 	}
933 
934 	dmabuf->mdev_state = mdev_state;
935 	list_add(&dmabuf->next, &mdev_state->dmabufs);
936 
937 	mbochs_print_dmabuf(dmabuf, __func__);
938 	return dmabuf;
939 
940 err_free_pages:
941 	while (pg > 0)
942 		put_page(dmabuf->pages[--pg]);
943 	kfree(dmabuf->pages);
944 err_free_dmabuf:
945 	kfree(dmabuf);
946 	return NULL;
947 }
948 
949 static struct mbochs_dmabuf *
950 mbochs_dmabuf_find_by_mode(struct mdev_state *mdev_state,
951 			   struct mbochs_mode *mode)
952 {
953 	struct mbochs_dmabuf *dmabuf;
954 
955 	WARN_ON(!mutex_is_locked(&mdev_state->ops_lock));
956 
957 	list_for_each_entry(dmabuf, &mdev_state->dmabufs, next)
958 		if (mbochs_modes_equal(&dmabuf->mode, mode))
959 			return dmabuf;
960 
961 	return NULL;
962 }
963 
964 static struct mbochs_dmabuf *
965 mbochs_dmabuf_find_by_id(struct mdev_state *mdev_state, u32 id)
966 {
967 	struct mbochs_dmabuf *dmabuf;
968 
969 	WARN_ON(!mutex_is_locked(&mdev_state->ops_lock));
970 
971 	list_for_each_entry(dmabuf, &mdev_state->dmabufs, next)
972 		if (dmabuf->id == id)
973 			return dmabuf;
974 
975 	return NULL;
976 }
977 
978 static int mbochs_dmabuf_export(struct mbochs_dmabuf *dmabuf)
979 {
980 	struct mdev_state *mdev_state = dmabuf->mdev_state;
981 	struct device *dev = mdev_state->vdev.dev;
982 	DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
983 	struct dma_buf *buf;
984 
985 	WARN_ON(!mutex_is_locked(&mdev_state->ops_lock));
986 
987 	if (!IS_ALIGNED(dmabuf->mode.offset, PAGE_SIZE)) {
988 		dev_info_ratelimited(dev, "%s: framebuffer not page-aligned\n",
989 				     __func__);
990 		return -EINVAL;
991 	}
992 
993 	exp_info.ops = &mbochs_dmabuf_ops;
994 	exp_info.size = dmabuf->mode.size;
995 	exp_info.priv = dmabuf;
996 
997 	buf = dma_buf_export(&exp_info);
998 	if (IS_ERR(buf)) {
999 		dev_info_ratelimited(dev, "%s: dma_buf_export failed: %ld\n",
1000 				     __func__, PTR_ERR(buf));
1001 		return PTR_ERR(buf);
1002 	}
1003 
1004 	dmabuf->buf = buf;
1005 	dev_dbg(dev, "%s: %d\n", __func__, dmabuf->id);
1006 	return 0;
1007 }
1008 
1009 static int mbochs_get_region_info(struct mdev_state *mdev_state,
1010 				  struct vfio_region_info_ext *ext)
1011 {
1012 	struct vfio_region_info *region_info = &ext->base;
1013 
1014 	if (region_info->index >= MBOCHS_NUM_REGIONS)
1015 		return -EINVAL;
1016 
1017 	switch (region_info->index) {
1018 	case VFIO_PCI_CONFIG_REGION_INDEX:
1019 		region_info->offset = 0;
1020 		region_info->size   = MBOCHS_CONFIG_SPACE_SIZE;
1021 		region_info->flags  = (VFIO_REGION_INFO_FLAG_READ |
1022 				       VFIO_REGION_INFO_FLAG_WRITE);
1023 		break;
1024 	case VFIO_PCI_BAR0_REGION_INDEX:
1025 		region_info->offset = MBOCHS_MEMORY_BAR_OFFSET;
1026 		region_info->size   = mdev_state->memsize;
1027 		region_info->flags  = (VFIO_REGION_INFO_FLAG_READ  |
1028 				       VFIO_REGION_INFO_FLAG_WRITE |
1029 				       VFIO_REGION_INFO_FLAG_MMAP);
1030 		break;
1031 	case VFIO_PCI_BAR2_REGION_INDEX:
1032 		region_info->offset = MBOCHS_MMIO_BAR_OFFSET;
1033 		region_info->size   = MBOCHS_MMIO_BAR_SIZE;
1034 		region_info->flags  = (VFIO_REGION_INFO_FLAG_READ  |
1035 				       VFIO_REGION_INFO_FLAG_WRITE);
1036 		break;
1037 	case MBOCHS_EDID_REGION_INDEX:
1038 		ext->base.argsz = sizeof(*ext);
1039 		ext->base.offset = MBOCHS_EDID_OFFSET;
1040 		ext->base.size = MBOCHS_EDID_SIZE;
1041 		ext->base.flags = (VFIO_REGION_INFO_FLAG_READ  |
1042 				   VFIO_REGION_INFO_FLAG_WRITE |
1043 				   VFIO_REGION_INFO_FLAG_CAPS);
1044 		ext->base.cap_offset = offsetof(typeof(*ext), type);
1045 		ext->type.header.id = VFIO_REGION_INFO_CAP_TYPE;
1046 		ext->type.header.version = 1;
1047 		ext->type.header.next = 0;
1048 		ext->type.type = VFIO_REGION_TYPE_GFX;
1049 		ext->type.subtype = VFIO_REGION_SUBTYPE_GFX_EDID;
1050 		break;
1051 	default:
1052 		region_info->size   = 0;
1053 		region_info->offset = 0;
1054 		region_info->flags  = 0;
1055 	}
1056 
1057 	return 0;
1058 }
1059 
1060 static int mbochs_get_irq_info(struct vfio_irq_info *irq_info)
1061 {
1062 	irq_info->count = 0;
1063 	return 0;
1064 }
1065 
1066 static int mbochs_get_device_info(struct vfio_device_info *dev_info)
1067 {
1068 	dev_info->flags = VFIO_DEVICE_FLAGS_PCI;
1069 	dev_info->num_regions = MBOCHS_NUM_REGIONS;
1070 	dev_info->num_irqs = VFIO_PCI_NUM_IRQS;
1071 	return 0;
1072 }
1073 
1074 static int mbochs_query_gfx_plane(struct mdev_state *mdev_state,
1075 				  struct vfio_device_gfx_plane_info *plane)
1076 {
1077 	struct mbochs_dmabuf *dmabuf;
1078 	struct mbochs_mode mode;
1079 	int ret;
1080 
1081 	if (plane->flags & VFIO_GFX_PLANE_TYPE_PROBE) {
1082 		if (plane->flags == (VFIO_GFX_PLANE_TYPE_PROBE |
1083 				     VFIO_GFX_PLANE_TYPE_DMABUF))
1084 			return 0;
1085 		return -EINVAL;
1086 	}
1087 
1088 	if (plane->flags != VFIO_GFX_PLANE_TYPE_DMABUF)
1089 		return -EINVAL;
1090 
1091 	plane->drm_format_mod = 0;
1092 	plane->x_pos	      = 0;
1093 	plane->y_pos	      = 0;
1094 	plane->x_hot	      = 0;
1095 	plane->y_hot	      = 0;
1096 
1097 	mutex_lock(&mdev_state->ops_lock);
1098 
1099 	ret = -EINVAL;
1100 	if (plane->drm_plane_type == DRM_PLANE_TYPE_PRIMARY)
1101 		ret = mbochs_check_framebuffer(mdev_state, &mode);
1102 	if (ret < 0) {
1103 		plane->drm_format     = 0;
1104 		plane->width	      = 0;
1105 		plane->height	      = 0;
1106 		plane->stride	      = 0;
1107 		plane->size	      = 0;
1108 		plane->dmabuf_id      = 0;
1109 		goto done;
1110 	}
1111 
1112 	dmabuf = mbochs_dmabuf_find_by_mode(mdev_state, &mode);
1113 	if (!dmabuf)
1114 		mbochs_dmabuf_alloc(mdev_state, &mode);
1115 	if (!dmabuf) {
1116 		mutex_unlock(&mdev_state->ops_lock);
1117 		return -ENOMEM;
1118 	}
1119 
1120 	plane->drm_format     = dmabuf->mode.drm_format;
1121 	plane->width	      = dmabuf->mode.width;
1122 	plane->height	      = dmabuf->mode.height;
1123 	plane->stride	      = dmabuf->mode.stride;
1124 	plane->size	      = dmabuf->mode.size;
1125 	plane->dmabuf_id      = dmabuf->id;
1126 
1127 done:
1128 	if (plane->drm_plane_type == DRM_PLANE_TYPE_PRIMARY &&
1129 	    mdev_state->active_id != plane->dmabuf_id) {
1130 		dev_dbg(mdev_state->vdev.dev, "%s: primary: %d => %d\n",
1131 			__func__, mdev_state->active_id, plane->dmabuf_id);
1132 		mdev_state->active_id = plane->dmabuf_id;
1133 	}
1134 	mutex_unlock(&mdev_state->ops_lock);
1135 	return 0;
1136 }
1137 
1138 static int mbochs_get_gfx_dmabuf(struct mdev_state *mdev_state, u32 id)
1139 {
1140 	struct mbochs_dmabuf *dmabuf;
1141 
1142 	mutex_lock(&mdev_state->ops_lock);
1143 
1144 	dmabuf = mbochs_dmabuf_find_by_id(mdev_state, id);
1145 	if (!dmabuf) {
1146 		mutex_unlock(&mdev_state->ops_lock);
1147 		return -ENOENT;
1148 	}
1149 
1150 	if (!dmabuf->buf)
1151 		mbochs_dmabuf_export(dmabuf);
1152 
1153 	mutex_unlock(&mdev_state->ops_lock);
1154 
1155 	if (!dmabuf->buf)
1156 		return -EINVAL;
1157 
1158 	return dma_buf_fd(dmabuf->buf, 0);
1159 }
1160 
1161 static long mbochs_ioctl(struct vfio_device *vdev, unsigned int cmd,
1162 			 unsigned long arg)
1163 {
1164 	struct mdev_state *mdev_state =
1165 		container_of(vdev, struct mdev_state, vdev);
1166 	int ret = 0;
1167 	unsigned long minsz, outsz;
1168 
1169 	switch (cmd) {
1170 	case VFIO_DEVICE_GET_INFO:
1171 	{
1172 		struct vfio_device_info info;
1173 
1174 		minsz = offsetofend(struct vfio_device_info, num_irqs);
1175 
1176 		if (copy_from_user(&info, (void __user *)arg, minsz))
1177 			return -EFAULT;
1178 
1179 		if (info.argsz < minsz)
1180 			return -EINVAL;
1181 
1182 		ret = mbochs_get_device_info(&info);
1183 		if (ret)
1184 			return ret;
1185 
1186 		if (copy_to_user((void __user *)arg, &info, minsz))
1187 			return -EFAULT;
1188 
1189 		return 0;
1190 	}
1191 	case VFIO_DEVICE_GET_REGION_INFO:
1192 	{
1193 		struct vfio_region_info_ext info;
1194 
1195 		minsz = offsetofend(typeof(info), base.offset);
1196 
1197 		if (copy_from_user(&info, (void __user *)arg, minsz))
1198 			return -EFAULT;
1199 
1200 		outsz = info.base.argsz;
1201 		if (outsz < minsz)
1202 			return -EINVAL;
1203 		if (outsz > sizeof(info))
1204 			return -EINVAL;
1205 
1206 		ret = mbochs_get_region_info(mdev_state, &info);
1207 		if (ret)
1208 			return ret;
1209 
1210 		if (copy_to_user((void __user *)arg, &info, outsz))
1211 			return -EFAULT;
1212 
1213 		return 0;
1214 	}
1215 
1216 	case VFIO_DEVICE_GET_IRQ_INFO:
1217 	{
1218 		struct vfio_irq_info info;
1219 
1220 		minsz = offsetofend(struct vfio_irq_info, count);
1221 
1222 		if (copy_from_user(&info, (void __user *)arg, minsz))
1223 			return -EFAULT;
1224 
1225 		if ((info.argsz < minsz) ||
1226 		    (info.index >= VFIO_PCI_NUM_IRQS))
1227 			return -EINVAL;
1228 
1229 		ret = mbochs_get_irq_info(&info);
1230 		if (ret)
1231 			return ret;
1232 
1233 		if (copy_to_user((void __user *)arg, &info, minsz))
1234 			return -EFAULT;
1235 
1236 		return 0;
1237 	}
1238 
1239 	case VFIO_DEVICE_QUERY_GFX_PLANE:
1240 	{
1241 		struct vfio_device_gfx_plane_info plane;
1242 
1243 		minsz = offsetofend(struct vfio_device_gfx_plane_info,
1244 				    region_index);
1245 
1246 		if (copy_from_user(&plane, (void __user *)arg, minsz))
1247 			return -EFAULT;
1248 
1249 		if (plane.argsz < minsz)
1250 			return -EINVAL;
1251 
1252 		ret = mbochs_query_gfx_plane(mdev_state, &plane);
1253 		if (ret)
1254 			return ret;
1255 
1256 		if (copy_to_user((void __user *)arg, &plane, minsz))
1257 			return -EFAULT;
1258 
1259 		return 0;
1260 	}
1261 
1262 	case VFIO_DEVICE_GET_GFX_DMABUF:
1263 	{
1264 		u32 dmabuf_id;
1265 
1266 		if (get_user(dmabuf_id, (__u32 __user *)arg))
1267 			return -EFAULT;
1268 
1269 		return mbochs_get_gfx_dmabuf(mdev_state, dmabuf_id);
1270 	}
1271 
1272 	case VFIO_DEVICE_SET_IRQS:
1273 		return -EINVAL;
1274 
1275 	case VFIO_DEVICE_RESET:
1276 		return mbochs_reset(mdev_state);
1277 	}
1278 	return -ENOTTY;
1279 }
1280 
1281 static void mbochs_close_device(struct vfio_device *vdev)
1282 {
1283 	struct mdev_state *mdev_state =
1284 		container_of(vdev, struct mdev_state, vdev);
1285 	struct mbochs_dmabuf *dmabuf, *tmp;
1286 
1287 	mutex_lock(&mdev_state->ops_lock);
1288 
1289 	list_for_each_entry_safe(dmabuf, tmp, &mdev_state->dmabufs, next) {
1290 		list_del(&dmabuf->next);
1291 		if (dmabuf->buf) {
1292 			/* free in mbochs_release_dmabuf() */
1293 			dmabuf->unlinked = true;
1294 		} else {
1295 			kfree(dmabuf);
1296 		}
1297 	}
1298 	mbochs_put_pages(mdev_state);
1299 
1300 	mutex_unlock(&mdev_state->ops_lock);
1301 }
1302 
1303 static ssize_t
1304 memory_show(struct device *dev, struct device_attribute *attr,
1305 	    char *buf)
1306 {
1307 	struct mdev_state *mdev_state = dev_get_drvdata(dev);
1308 
1309 	return sprintf(buf, "%d MB\n", mdev_state->type->mbytes);
1310 }
1311 static DEVICE_ATTR_RO(memory);
1312 
1313 static struct attribute *mdev_dev_attrs[] = {
1314 	&dev_attr_memory.attr,
1315 	NULL,
1316 };
1317 
1318 static const struct attribute_group mdev_dev_group = {
1319 	.name  = "vendor",
1320 	.attrs = mdev_dev_attrs,
1321 };
1322 
1323 static const struct attribute_group *mdev_dev_groups[] = {
1324 	&mdev_dev_group,
1325 	NULL,
1326 };
1327 
1328 static ssize_t name_show(struct mdev_type *mtype,
1329 			 struct mdev_type_attribute *attr, char *buf)
1330 {
1331 	const struct mbochs_type *type =
1332 		&mbochs_types[mtype_get_type_group_id(mtype)];
1333 
1334 	return sprintf(buf, "%s\n", type->name);
1335 }
1336 static MDEV_TYPE_ATTR_RO(name);
1337 
1338 static ssize_t description_show(struct mdev_type *mtype,
1339 				struct mdev_type_attribute *attr, char *buf)
1340 {
1341 	const struct mbochs_type *type =
1342 		&mbochs_types[mtype_get_type_group_id(mtype)];
1343 
1344 	return sprintf(buf, "virtual display, %d MB video memory\n",
1345 		       type ? type->mbytes  : 0);
1346 }
1347 static MDEV_TYPE_ATTR_RO(description);
1348 
1349 static ssize_t available_instances_show(struct mdev_type *mtype,
1350 					struct mdev_type_attribute *attr,
1351 					char *buf)
1352 {
1353 	const struct mbochs_type *type =
1354 		&mbochs_types[mtype_get_type_group_id(mtype)];
1355 	int count = atomic_read(&mbochs_avail_mbytes) / type->mbytes;
1356 
1357 	return sprintf(buf, "%d\n", count);
1358 }
1359 static MDEV_TYPE_ATTR_RO(available_instances);
1360 
1361 static ssize_t device_api_show(struct mdev_type *mtype,
1362 			       struct mdev_type_attribute *attr, char *buf)
1363 {
1364 	return sprintf(buf, "%s\n", VFIO_DEVICE_API_PCI_STRING);
1365 }
1366 static MDEV_TYPE_ATTR_RO(device_api);
1367 
1368 static struct attribute *mdev_types_attrs[] = {
1369 	&mdev_type_attr_name.attr,
1370 	&mdev_type_attr_description.attr,
1371 	&mdev_type_attr_device_api.attr,
1372 	&mdev_type_attr_available_instances.attr,
1373 	NULL,
1374 };
1375 
1376 static struct attribute_group mdev_type_group1 = {
1377 	.name  = MBOCHS_TYPE_1,
1378 	.attrs = mdev_types_attrs,
1379 };
1380 
1381 static struct attribute_group mdev_type_group2 = {
1382 	.name  = MBOCHS_TYPE_2,
1383 	.attrs = mdev_types_attrs,
1384 };
1385 
1386 static struct attribute_group mdev_type_group3 = {
1387 	.name  = MBOCHS_TYPE_3,
1388 	.attrs = mdev_types_attrs,
1389 };
1390 
1391 static struct attribute_group *mdev_type_groups[] = {
1392 	&mdev_type_group1,
1393 	&mdev_type_group2,
1394 	&mdev_type_group3,
1395 	NULL,
1396 };
1397 
1398 static const struct vfio_device_ops mbochs_dev_ops = {
1399 	.close_device = mbochs_close_device,
1400 	.read = mbochs_read,
1401 	.write = mbochs_write,
1402 	.ioctl = mbochs_ioctl,
1403 	.mmap = mbochs_mmap,
1404 };
1405 
1406 static struct mdev_driver mbochs_driver = {
1407 	.driver = {
1408 		.name = "mbochs",
1409 		.owner = THIS_MODULE,
1410 		.mod_name = KBUILD_MODNAME,
1411 		.dev_groups = mdev_dev_groups,
1412 	},
1413 	.probe = mbochs_probe,
1414 	.remove	= mbochs_remove,
1415 };
1416 
1417 static const struct mdev_parent_ops mdev_fops = {
1418 	.owner			= THIS_MODULE,
1419 	.device_driver		= &mbochs_driver,
1420 	.supported_type_groups	= mdev_type_groups,
1421 };
1422 
1423 static const struct file_operations vd_fops = {
1424 	.owner		= THIS_MODULE,
1425 };
1426 
1427 static void mbochs_device_release(struct device *dev)
1428 {
1429 	/* nothing */
1430 }
1431 
1432 static int __init mbochs_dev_init(void)
1433 {
1434 	int ret = 0;
1435 
1436 	atomic_set(&mbochs_avail_mbytes, max_mbytes);
1437 
1438 	ret = alloc_chrdev_region(&mbochs_devt, 0, MINORMASK + 1, MBOCHS_NAME);
1439 	if (ret < 0) {
1440 		pr_err("Error: failed to register mbochs_dev, err: %d\n", ret);
1441 		return ret;
1442 	}
1443 	cdev_init(&mbochs_cdev, &vd_fops);
1444 	cdev_add(&mbochs_cdev, mbochs_devt, MINORMASK + 1);
1445 	pr_info("%s: major %d\n", __func__, MAJOR(mbochs_devt));
1446 
1447 	ret = mdev_register_driver(&mbochs_driver);
1448 	if (ret)
1449 		goto err_cdev;
1450 
1451 	mbochs_class = class_create(THIS_MODULE, MBOCHS_CLASS_NAME);
1452 	if (IS_ERR(mbochs_class)) {
1453 		pr_err("Error: failed to register mbochs_dev class\n");
1454 		ret = PTR_ERR(mbochs_class);
1455 		goto err_driver;
1456 	}
1457 	mbochs_dev.class = mbochs_class;
1458 	mbochs_dev.release = mbochs_device_release;
1459 	dev_set_name(&mbochs_dev, "%s", MBOCHS_NAME);
1460 
1461 	ret = device_register(&mbochs_dev);
1462 	if (ret)
1463 		goto err_class;
1464 
1465 	ret = mdev_register_device(&mbochs_dev, &mdev_fops);
1466 	if (ret)
1467 		goto err_device;
1468 
1469 	return 0;
1470 
1471 err_device:
1472 	device_unregister(&mbochs_dev);
1473 err_class:
1474 	class_destroy(mbochs_class);
1475 err_driver:
1476 	mdev_unregister_driver(&mbochs_driver);
1477 err_cdev:
1478 	cdev_del(&mbochs_cdev);
1479 	unregister_chrdev_region(mbochs_devt, MINORMASK + 1);
1480 	return ret;
1481 }
1482 
1483 static void __exit mbochs_dev_exit(void)
1484 {
1485 	mbochs_dev.bus = NULL;
1486 	mdev_unregister_device(&mbochs_dev);
1487 
1488 	device_unregister(&mbochs_dev);
1489 	mdev_unregister_driver(&mbochs_driver);
1490 	cdev_del(&mbochs_cdev);
1491 	unregister_chrdev_region(mbochs_devt, MINORMASK + 1);
1492 	class_destroy(mbochs_class);
1493 	mbochs_class = NULL;
1494 }
1495 
1496 module_init(mbochs_dev_init)
1497 module_exit(mbochs_dev_exit)
1498