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v6.8
   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/kernel.h>
  25#include <linux/slab.h>
  26#include <linux/vmalloc.h>
  27#include <linux/cdev.h>
  28#include <linux/vfio.h>
  29#include <linux/iommu.h>
  30#include <linux/sysfs.h>
  31#include <linux/mdev.h>
  32#include <linux/pci.h>
  33#include <linux/dma-buf.h>
  34#include <linux/highmem.h>
  35#include <drm/drm_fourcc.h>
  36#include <drm/drm_rect.h>
  37#include <drm/drm_modeset_lock.h>
  38#include <drm/drm_property.h>
  39#include <drm/drm_plane.h>
  40
  41
  42#define VBE_DISPI_INDEX_ID		0x0
  43#define VBE_DISPI_INDEX_XRES		0x1
  44#define VBE_DISPI_INDEX_YRES		0x2
  45#define VBE_DISPI_INDEX_BPP		0x3
  46#define VBE_DISPI_INDEX_ENABLE		0x4
  47#define VBE_DISPI_INDEX_BANK		0x5
  48#define VBE_DISPI_INDEX_VIRT_WIDTH	0x6
  49#define VBE_DISPI_INDEX_VIRT_HEIGHT	0x7
  50#define VBE_DISPI_INDEX_X_OFFSET	0x8
  51#define VBE_DISPI_INDEX_Y_OFFSET	0x9
  52#define VBE_DISPI_INDEX_VIDEO_MEMORY_64K 0xa
  53#define VBE_DISPI_INDEX_COUNT		0xb
  54
  55#define VBE_DISPI_ID0			0xB0C0
  56#define VBE_DISPI_ID1			0xB0C1
  57#define VBE_DISPI_ID2			0xB0C2
  58#define VBE_DISPI_ID3			0xB0C3
  59#define VBE_DISPI_ID4			0xB0C4
  60#define VBE_DISPI_ID5			0xB0C5
  61
  62#define VBE_DISPI_DISABLED		0x00
  63#define VBE_DISPI_ENABLED		0x01
  64#define VBE_DISPI_GETCAPS		0x02
  65#define VBE_DISPI_8BIT_DAC		0x20
  66#define VBE_DISPI_LFB_ENABLED		0x40
  67#define VBE_DISPI_NOCLEARMEM		0x80
  68
  69
  70#define MBOCHS_NAME		  "mbochs"
  71#define MBOCHS_CLASS_NAME	  "mbochs"
  72
  73#define MBOCHS_EDID_REGION_INDEX  VFIO_PCI_NUM_REGIONS
  74#define MBOCHS_NUM_REGIONS        (MBOCHS_EDID_REGION_INDEX+1)
  75
  76#define MBOCHS_CONFIG_SPACE_SIZE  0xff
  77#define MBOCHS_MMIO_BAR_OFFSET	  PAGE_SIZE
  78#define MBOCHS_MMIO_BAR_SIZE	  PAGE_SIZE
  79#define MBOCHS_EDID_OFFSET	  (MBOCHS_MMIO_BAR_OFFSET +	\
  80				   MBOCHS_MMIO_BAR_SIZE)
  81#define MBOCHS_EDID_SIZE	  PAGE_SIZE
  82#define MBOCHS_MEMORY_BAR_OFFSET  (MBOCHS_EDID_OFFSET + \
  83				   MBOCHS_EDID_SIZE)
  84
  85#define MBOCHS_EDID_BLOB_OFFSET   (MBOCHS_EDID_SIZE/2)
  86
  87#define STORE_LE16(addr, val)	(*(u16 *)addr = val)
  88#define STORE_LE32(addr, val)	(*(u32 *)addr = val)
  89
  90
  91MODULE_LICENSE("GPL v2");
  92
  93static int max_mbytes = 256;
  94module_param_named(count, max_mbytes, int, 0444);
  95MODULE_PARM_DESC(mem, "megabytes available to " MBOCHS_NAME " devices");
  96
  97
  98#define MBOCHS_TYPE_1 "small"
  99#define MBOCHS_TYPE_2 "medium"
 100#define MBOCHS_TYPE_3 "large"
 101
 102static struct mbochs_type {
 103	struct mdev_type type;
 104	u32 mbytes;
 105	u32 max_x;
 106	u32 max_y;
 107} mbochs_types[] = {
 108	{
 109		.type.sysfs_name	= MBOCHS_TYPE_1,
 110		.type.pretty_name	= MBOCHS_CLASS_NAME "-" MBOCHS_TYPE_1,
 111		.mbytes = 4,
 112		.max_x  = 800,
 113		.max_y  = 600,
 114	}, {
 115		.type.sysfs_name	= MBOCHS_TYPE_2,
 116		.type.pretty_name	= MBOCHS_CLASS_NAME "-" MBOCHS_TYPE_2,
 117		.mbytes = 16,
 118		.max_x  = 1920,
 119		.max_y  = 1440,
 120	}, {
 121		.type.sysfs_name	= MBOCHS_TYPE_3,
 122		.type.pretty_name	= MBOCHS_CLASS_NAME "-" MBOCHS_TYPE_3,
 123		.mbytes = 64,
 124		.max_x  = 0,
 125		.max_y  = 0,
 126	},
 127};
 128
 129static struct mdev_type *mbochs_mdev_types[] = {
 130	&mbochs_types[0].type,
 131	&mbochs_types[1].type,
 132	&mbochs_types[2].type,
 133};
 134
 135static dev_t		mbochs_devt;
 136static struct class	*mbochs_class;
 
 
 137static struct cdev	mbochs_cdev;
 138static struct device	mbochs_dev;
 139static struct mdev_parent mbochs_parent;
 140static atomic_t mbochs_avail_mbytes;
 141static const struct vfio_device_ops mbochs_dev_ops;
 142
 143struct vfio_region_info_ext {
 144	struct vfio_region_info          base;
 145	struct vfio_region_info_cap_type type;
 146};
 147
 148struct mbochs_mode {
 149	u32 drm_format;
 150	u32 bytepp;
 151	u32 width;
 152	u32 height;
 153	u32 stride;
 154	u32 __pad;
 155	u64 offset;
 156	u64 size;
 157};
 158
 159struct mbochs_dmabuf {
 160	struct mbochs_mode mode;
 161	u32 id;
 162	struct page **pages;
 163	pgoff_t pagecount;
 164	struct dma_buf *buf;
 165	struct mdev_state *mdev_state;
 166	struct list_head next;
 167	bool unlinked;
 168};
 169
 170/* State of each mdev device */
 171struct mdev_state {
 172	struct vfio_device vdev;
 173	u8 *vconfig;
 174	u64 bar_mask[3];
 175	u32 memory_bar_mask;
 176	struct mutex ops_lock;
 177	struct mdev_device *mdev;
 178
 179	const struct mbochs_type *type;
 180	u16 vbe[VBE_DISPI_INDEX_COUNT];
 181	u64 memsize;
 182	struct page **pages;
 183	pgoff_t pagecount;
 184	struct vfio_region_gfx_edid edid_regs;
 185	u8 edid_blob[0x400];
 186
 187	struct list_head dmabufs;
 188	u32 active_id;
 189	u32 next_id;
 190};
 191
 192static const char *vbe_name_list[VBE_DISPI_INDEX_COUNT] = {
 193	[VBE_DISPI_INDEX_ID]               = "id",
 194	[VBE_DISPI_INDEX_XRES]             = "xres",
 195	[VBE_DISPI_INDEX_YRES]             = "yres",
 196	[VBE_DISPI_INDEX_BPP]              = "bpp",
 197	[VBE_DISPI_INDEX_ENABLE]           = "enable",
 198	[VBE_DISPI_INDEX_BANK]             = "bank",
 199	[VBE_DISPI_INDEX_VIRT_WIDTH]       = "virt-width",
 200	[VBE_DISPI_INDEX_VIRT_HEIGHT]      = "virt-height",
 201	[VBE_DISPI_INDEX_X_OFFSET]         = "x-offset",
 202	[VBE_DISPI_INDEX_Y_OFFSET]         = "y-offset",
 203	[VBE_DISPI_INDEX_VIDEO_MEMORY_64K] = "video-mem",
 204};
 205
 206static const char *vbe_name(u32 index)
 207{
 208	if (index < ARRAY_SIZE(vbe_name_list))
 209		return vbe_name_list[index];
 210	return "(invalid)";
 211}
 212
 213static struct page *__mbochs_get_page(struct mdev_state *mdev_state,
 214				      pgoff_t pgoff);
 215static struct page *mbochs_get_page(struct mdev_state *mdev_state,
 216				    pgoff_t pgoff);
 217
 218static void mbochs_create_config_space(struct mdev_state *mdev_state)
 219{
 220	STORE_LE16((u16 *) &mdev_state->vconfig[PCI_VENDOR_ID],
 221		   0x1234);
 222	STORE_LE16((u16 *) &mdev_state->vconfig[PCI_DEVICE_ID],
 223		   0x1111);
 224	STORE_LE16((u16 *) &mdev_state->vconfig[PCI_SUBSYSTEM_VENDOR_ID],
 225		   PCI_SUBVENDOR_ID_REDHAT_QUMRANET);
 226	STORE_LE16((u16 *) &mdev_state->vconfig[PCI_SUBSYSTEM_ID],
 227		   PCI_SUBDEVICE_ID_QEMU);
 228
 229	STORE_LE16((u16 *) &mdev_state->vconfig[PCI_COMMAND],
 230		   PCI_COMMAND_IO | PCI_COMMAND_MEMORY);
 231	STORE_LE16((u16 *) &mdev_state->vconfig[PCI_CLASS_DEVICE],
 232		   PCI_CLASS_DISPLAY_OTHER);
 233	mdev_state->vconfig[PCI_CLASS_REVISION] =  0x01;
 234
 235	STORE_LE32((u32 *) &mdev_state->vconfig[PCI_BASE_ADDRESS_0],
 236		   PCI_BASE_ADDRESS_SPACE_MEMORY |
 237		   PCI_BASE_ADDRESS_MEM_TYPE_32	 |
 238		   PCI_BASE_ADDRESS_MEM_PREFETCH);
 239	mdev_state->bar_mask[0] = ~(mdev_state->memsize) + 1;
 240
 241	STORE_LE32((u32 *) &mdev_state->vconfig[PCI_BASE_ADDRESS_2],
 242		   PCI_BASE_ADDRESS_SPACE_MEMORY |
 243		   PCI_BASE_ADDRESS_MEM_TYPE_32);
 244	mdev_state->bar_mask[2] = ~(MBOCHS_MMIO_BAR_SIZE) + 1;
 245}
 246
 247static int mbochs_check_framebuffer(struct mdev_state *mdev_state,
 248				    struct mbochs_mode *mode)
 249{
 250	struct device *dev = mdev_dev(mdev_state->mdev);
 251	u16 *vbe = mdev_state->vbe;
 252	u32 virt_width;
 253
 254	WARN_ON(!mutex_is_locked(&mdev_state->ops_lock));
 255
 256	if (!(vbe[VBE_DISPI_INDEX_ENABLE] & VBE_DISPI_ENABLED))
 257		goto nofb;
 258
 259	memset(mode, 0, sizeof(*mode));
 260	switch (vbe[VBE_DISPI_INDEX_BPP]) {
 261	case 32:
 262		mode->drm_format = DRM_FORMAT_XRGB8888;
 263		mode->bytepp = 4;
 264		break;
 265	default:
 266		dev_info_ratelimited(dev, "%s: bpp %d not supported\n",
 267				     __func__, vbe[VBE_DISPI_INDEX_BPP]);
 268		goto nofb;
 269	}
 270
 271	mode->width  = vbe[VBE_DISPI_INDEX_XRES];
 272	mode->height = vbe[VBE_DISPI_INDEX_YRES];
 273	virt_width  = vbe[VBE_DISPI_INDEX_VIRT_WIDTH];
 274	if (virt_width < mode->width)
 275		virt_width = mode->width;
 276	mode->stride = virt_width * mode->bytepp;
 277	mode->size   = (u64)mode->stride * mode->height;
 278	mode->offset = ((u64)vbe[VBE_DISPI_INDEX_X_OFFSET] * mode->bytepp +
 279		       (u64)vbe[VBE_DISPI_INDEX_Y_OFFSET] * mode->stride);
 280
 281	if (mode->width < 64 || mode->height < 64) {
 282		dev_info_ratelimited(dev, "%s: invalid resolution %dx%d\n",
 283				     __func__, mode->width, mode->height);
 284		goto nofb;
 285	}
 286	if (mode->offset + mode->size > mdev_state->memsize) {
 287		dev_info_ratelimited(dev, "%s: framebuffer memory overflow\n",
 288				     __func__);
 289		goto nofb;
 290	}
 291
 292	return 0;
 293
 294nofb:
 295	memset(mode, 0, sizeof(*mode));
 296	return -EINVAL;
 297}
 298
 299static bool mbochs_modes_equal(struct mbochs_mode *mode1,
 300			       struct mbochs_mode *mode2)
 301{
 302	return memcmp(mode1, mode2, sizeof(struct mbochs_mode)) == 0;
 303}
 304
 305static void handle_pci_cfg_write(struct mdev_state *mdev_state, u16 offset,
 306				 char *buf, u32 count)
 307{
 308	struct device *dev = mdev_dev(mdev_state->mdev);
 309	int index = (offset - PCI_BASE_ADDRESS_0) / 0x04;
 310	u32 cfg_addr;
 311
 312	switch (offset) {
 313	case PCI_BASE_ADDRESS_0:
 314	case PCI_BASE_ADDRESS_2:
 315		cfg_addr = *(u32 *)buf;
 316
 317		if (cfg_addr == 0xffffffff) {
 318			cfg_addr = (cfg_addr & mdev_state->bar_mask[index]);
 319		} else {
 320			cfg_addr &= PCI_BASE_ADDRESS_MEM_MASK;
 321			if (cfg_addr)
 322				dev_info(dev, "BAR #%d @ 0x%x\n",
 323					 index, cfg_addr);
 324		}
 325
 326		cfg_addr |= (mdev_state->vconfig[offset] &
 327			     ~PCI_BASE_ADDRESS_MEM_MASK);
 328		STORE_LE32(&mdev_state->vconfig[offset], cfg_addr);
 329		break;
 330	}
 331}
 332
 333static void handle_mmio_write(struct mdev_state *mdev_state, u16 offset,
 334			      char *buf, u32 count)
 335{
 336	struct device *dev = mdev_dev(mdev_state->mdev);
 337	int index;
 338	u16 reg16;
 339
 340	switch (offset) {
 341	case 0x400 ... 0x41f: /* vga ioports remapped */
 342		goto unhandled;
 343	case 0x500 ... 0x515: /* bochs dispi interface */
 344		if (count != 2)
 345			goto unhandled;
 346		index = (offset - 0x500) / 2;
 347		reg16 = *(u16 *)buf;
 348		if (index < ARRAY_SIZE(mdev_state->vbe))
 349			mdev_state->vbe[index] = reg16;
 350		dev_dbg(dev, "%s: vbe write %d = %d (%s)\n",
 351			__func__, index, reg16, vbe_name(index));
 352		break;
 353	case 0x600 ... 0x607: /* qemu extended regs */
 354		goto unhandled;
 355	default:
 356unhandled:
 357		dev_dbg(dev, "%s: @0x%03x, count %d (unhandled)\n",
 358			__func__, offset, count);
 359		break;
 360	}
 361}
 362
 363static void handle_mmio_read(struct mdev_state *mdev_state, u16 offset,
 364			     char *buf, u32 count)
 365{
 366	struct device *dev = mdev_dev(mdev_state->mdev);
 367	struct vfio_region_gfx_edid *edid;
 368	u16 reg16 = 0;
 369	int index;
 370
 371	switch (offset) {
 372	case 0x000 ... 0x3ff: /* edid block */
 373		edid = &mdev_state->edid_regs;
 374		if (edid->link_state != VFIO_DEVICE_GFX_LINK_STATE_UP ||
 375		    offset >= edid->edid_size) {
 376			memset(buf, 0, count);
 377			break;
 378		}
 379		memcpy(buf, mdev_state->edid_blob + offset, count);
 380		break;
 381	case 0x500 ... 0x515: /* bochs dispi interface */
 382		if (count != 2)
 383			goto unhandled;
 384		index = (offset - 0x500) / 2;
 385		if (index < ARRAY_SIZE(mdev_state->vbe))
 386			reg16 = mdev_state->vbe[index];
 387		dev_dbg(dev, "%s: vbe read %d = %d (%s)\n",
 388			__func__, index, reg16, vbe_name(index));
 389		*(u16 *)buf = reg16;
 390		break;
 391	default:
 392unhandled:
 393		dev_dbg(dev, "%s: @0x%03x, count %d (unhandled)\n",
 394			__func__, offset, count);
 395		memset(buf, 0, count);
 396		break;
 397	}
 398}
 399
 400static void handle_edid_regs(struct mdev_state *mdev_state, u16 offset,
 401			     char *buf, u32 count, bool is_write)
 402{
 403	char *regs = (void *)&mdev_state->edid_regs;
 404
 405	if (offset + count > sizeof(mdev_state->edid_regs))
 406		return;
 407	if (count != 4)
 408		return;
 409	if (offset % 4)
 410		return;
 411
 412	if (is_write) {
 413		switch (offset) {
 414		case offsetof(struct vfio_region_gfx_edid, link_state):
 415		case offsetof(struct vfio_region_gfx_edid, edid_size):
 416			memcpy(regs + offset, buf, count);
 417			break;
 418		default:
 419			/* read-only regs */
 420			break;
 421		}
 422	} else {
 423		memcpy(buf, regs + offset, count);
 424	}
 425}
 426
 427static void handle_edid_blob(struct mdev_state *mdev_state, u16 offset,
 428			     char *buf, u32 count, bool is_write)
 429{
 430	if (offset + count > mdev_state->edid_regs.edid_max_size)
 431		return;
 432	if (is_write)
 433		memcpy(mdev_state->edid_blob + offset, buf, count);
 434	else
 435		memcpy(buf, mdev_state->edid_blob + offset, count);
 436}
 437
 438static ssize_t mdev_access(struct mdev_state *mdev_state, char *buf,
 439			   size_t count, loff_t pos, bool is_write)
 440{
 441	struct page *pg;
 442	loff_t poff;
 443	char *map;
 444	int ret = 0;
 445
 446	mutex_lock(&mdev_state->ops_lock);
 447
 448	if (pos < MBOCHS_CONFIG_SPACE_SIZE) {
 449		if (is_write)
 450			handle_pci_cfg_write(mdev_state, pos, buf, count);
 451		else
 452			memcpy(buf, (mdev_state->vconfig + pos), count);
 453
 454	} else if (pos >= MBOCHS_MMIO_BAR_OFFSET &&
 455		   pos + count <= (MBOCHS_MMIO_BAR_OFFSET +
 456				   MBOCHS_MMIO_BAR_SIZE)) {
 457		pos -= MBOCHS_MMIO_BAR_OFFSET;
 458		if (is_write)
 459			handle_mmio_write(mdev_state, pos, buf, count);
 460		else
 461			handle_mmio_read(mdev_state, pos, buf, count);
 462
 463	} else if (pos >= MBOCHS_EDID_OFFSET &&
 464		   pos + count <= (MBOCHS_EDID_OFFSET +
 465				   MBOCHS_EDID_SIZE)) {
 466		pos -= MBOCHS_EDID_OFFSET;
 467		if (pos < MBOCHS_EDID_BLOB_OFFSET) {
 468			handle_edid_regs(mdev_state, pos, buf, count, is_write);
 469		} else {
 470			pos -= MBOCHS_EDID_BLOB_OFFSET;
 471			handle_edid_blob(mdev_state, pos, buf, count, is_write);
 472		}
 473
 474	} else if (pos >= MBOCHS_MEMORY_BAR_OFFSET &&
 475		   pos + count <=
 476		   MBOCHS_MEMORY_BAR_OFFSET + mdev_state->memsize) {
 477		pos -= MBOCHS_MMIO_BAR_OFFSET;
 478		poff = pos & ~PAGE_MASK;
 479		pg = __mbochs_get_page(mdev_state, pos >> PAGE_SHIFT);
 480		map = kmap(pg);
 481		if (is_write)
 482			memcpy(map + poff, buf, count);
 483		else
 484			memcpy(buf, map + poff, count);
 485		kunmap(pg);
 486		put_page(pg);
 487
 488	} else {
 489		dev_dbg(mdev_state->vdev.dev, "%s: %s @0x%llx (unhandled)\n",
 490			__func__, is_write ? "WR" : "RD", pos);
 491		ret = -1;
 492		goto accessfailed;
 493	}
 494
 495	ret = count;
 496
 497
 498accessfailed:
 499	mutex_unlock(&mdev_state->ops_lock);
 500
 501	return ret;
 502}
 503
 504static int mbochs_reset(struct mdev_state *mdev_state)
 505{
 506	u32 size64k = mdev_state->memsize / (64 * 1024);
 507	int i;
 508
 509	for (i = 0; i < ARRAY_SIZE(mdev_state->vbe); i++)
 510		mdev_state->vbe[i] = 0;
 511	mdev_state->vbe[VBE_DISPI_INDEX_ID] = VBE_DISPI_ID5;
 512	mdev_state->vbe[VBE_DISPI_INDEX_VIDEO_MEMORY_64K] = size64k;
 513	return 0;
 514}
 515
 516static int mbochs_init_dev(struct vfio_device *vdev)
 517{
 518	struct mdev_state *mdev_state =
 519		container_of(vdev, struct mdev_state, vdev);
 520	struct mdev_device *mdev = to_mdev_device(vdev->dev);
 521	struct mbochs_type *type =
 522		container_of(mdev->type, struct mbochs_type, type);
 523	int avail_mbytes = atomic_read(&mbochs_avail_mbytes);
 524	int ret = -ENOMEM;
 525
 526	do {
 527		if (avail_mbytes < type->mbytes)
 528			return -ENOSPC;
 529	} while (!atomic_try_cmpxchg(&mbochs_avail_mbytes, &avail_mbytes,
 530				     avail_mbytes - type->mbytes));
 531
 532	mdev_state->vconfig = kzalloc(MBOCHS_CONFIG_SPACE_SIZE, GFP_KERNEL);
 533	if (!mdev_state->vconfig)
 534		goto err_avail;
 535
 536	mdev_state->memsize = type->mbytes * 1024 * 1024;
 537	mdev_state->pagecount = mdev_state->memsize >> PAGE_SHIFT;
 538	mdev_state->pages = kcalloc(mdev_state->pagecount,
 539				    sizeof(struct page *),
 540				    GFP_KERNEL);
 541	if (!mdev_state->pages)
 542		goto err_vconfig;
 543
 544	mutex_init(&mdev_state->ops_lock);
 545	mdev_state->mdev = mdev;
 546	INIT_LIST_HEAD(&mdev_state->dmabufs);
 547	mdev_state->next_id = 1;
 548
 549	mdev_state->type = type;
 550	mdev_state->edid_regs.max_xres = type->max_x;
 551	mdev_state->edid_regs.max_yres = type->max_y;
 552	mdev_state->edid_regs.edid_offset = MBOCHS_EDID_BLOB_OFFSET;
 553	mdev_state->edid_regs.edid_max_size = sizeof(mdev_state->edid_blob);
 554	mbochs_create_config_space(mdev_state);
 555	mbochs_reset(mdev_state);
 556
 557	dev_info(vdev->dev, "%s: %s, %d MB, %ld pages\n", __func__,
 558		 type->type.pretty_name, type->mbytes, mdev_state->pagecount);
 559	return 0;
 560
 561err_vconfig:
 562	kfree(mdev_state->vconfig);
 563err_avail:
 564	atomic_add(type->mbytes, &mbochs_avail_mbytes);
 565	return ret;
 566}
 567
 568static int mbochs_probe(struct mdev_device *mdev)
 569{
 570	struct mdev_state *mdev_state;
 571	int ret = -ENOMEM;
 572
 573	mdev_state = vfio_alloc_device(mdev_state, vdev, &mdev->dev,
 574				       &mbochs_dev_ops);
 575	if (IS_ERR(mdev_state))
 576		return PTR_ERR(mdev_state);
 577
 578	ret = vfio_register_emulated_iommu_dev(&mdev_state->vdev);
 579	if (ret)
 580		goto err_put_vdev;
 581	dev_set_drvdata(&mdev->dev, mdev_state);
 582	return 0;
 583
 584err_put_vdev:
 585	vfio_put_device(&mdev_state->vdev);
 586	return ret;
 587}
 588
 589static void mbochs_release_dev(struct vfio_device *vdev)
 590{
 591	struct mdev_state *mdev_state =
 592		container_of(vdev, struct mdev_state, vdev);
 593
 594	atomic_add(mdev_state->type->mbytes, &mbochs_avail_mbytes);
 595	kfree(mdev_state->pages);
 596	kfree(mdev_state->vconfig);
 597}
 598
 599static void mbochs_remove(struct mdev_device *mdev)
 600{
 601	struct mdev_state *mdev_state = dev_get_drvdata(&mdev->dev);
 602
 603	vfio_unregister_group_dev(&mdev_state->vdev);
 604	vfio_put_device(&mdev_state->vdev);
 605}
 606
 607static ssize_t mbochs_read(struct vfio_device *vdev, char __user *buf,
 608			   size_t count, loff_t *ppos)
 609{
 610	struct mdev_state *mdev_state =
 611		container_of(vdev, struct mdev_state, vdev);
 612	unsigned int done = 0;
 613	int ret;
 614
 615	while (count) {
 616		size_t filled;
 617
 618		if (count >= 4 && !(*ppos % 4)) {
 619			u32 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 = 4;
 630		} else if (count >= 2 && !(*ppos % 2)) {
 631			u16 val;
 632
 633			ret = mdev_access(mdev_state, (char *)&val, sizeof(val),
 634					  *ppos, false);
 635			if (ret <= 0)
 636				goto read_err;
 637
 638			if (copy_to_user(buf, &val, sizeof(val)))
 639				goto read_err;
 640
 641			filled = 2;
 642		} else {
 643			u8 val;
 644
 645			ret = mdev_access(mdev_state, (char *)&val, sizeof(val),
 646					  *ppos, false);
 647			if (ret <= 0)
 648				goto read_err;
 649
 650			if (copy_to_user(buf, &val, sizeof(val)))
 651				goto read_err;
 652
 653			filled = 1;
 654		}
 655
 656		count -= filled;
 657		done += filled;
 658		*ppos += filled;
 659		buf += filled;
 660	}
 661
 662	return done;
 663
 664read_err:
 665	return -EFAULT;
 666}
 667
 668static ssize_t mbochs_write(struct vfio_device *vdev, const char __user *buf,
 669			    size_t count, loff_t *ppos)
 670{
 671	struct mdev_state *mdev_state =
 672		container_of(vdev, struct mdev_state, vdev);
 673	unsigned int done = 0;
 674	int ret;
 675
 676	while (count) {
 677		size_t filled;
 678
 679		if (count >= 4 && !(*ppos % 4)) {
 680			u32 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 = 4;
 691		} else if (count >= 2 && !(*ppos % 2)) {
 692			u16 val;
 693
 694			if (copy_from_user(&val, buf, sizeof(val)))
 695				goto write_err;
 696
 697			ret = mdev_access(mdev_state, (char *)&val, sizeof(val),
 698					  *ppos, true);
 699			if (ret <= 0)
 700				goto write_err;
 701
 702			filled = 2;
 703		} else {
 704			u8 val;
 705
 706			if (copy_from_user(&val, buf, sizeof(val)))
 707				goto write_err;
 708
 709			ret = mdev_access(mdev_state, (char *)&val, sizeof(val),
 710					  *ppos, true);
 711			if (ret <= 0)
 712				goto write_err;
 713
 714			filled = 1;
 715		}
 716		count -= filled;
 717		done += filled;
 718		*ppos += filled;
 719		buf += filled;
 720	}
 721
 722	return done;
 723write_err:
 724	return -EFAULT;
 725}
 726
 727static struct page *__mbochs_get_page(struct mdev_state *mdev_state,
 728				      pgoff_t pgoff)
 729{
 730	WARN_ON(!mutex_is_locked(&mdev_state->ops_lock));
 731
 732	if (!mdev_state->pages[pgoff]) {
 733		mdev_state->pages[pgoff] =
 734			alloc_pages(GFP_HIGHUSER | __GFP_ZERO, 0);
 735		if (!mdev_state->pages[pgoff])
 736			return NULL;
 737	}
 738
 739	get_page(mdev_state->pages[pgoff]);
 740	return mdev_state->pages[pgoff];
 741}
 742
 743static struct page *mbochs_get_page(struct mdev_state *mdev_state,
 744				    pgoff_t pgoff)
 745{
 746	struct page *page;
 747
 748	if (WARN_ON(pgoff >= mdev_state->pagecount))
 749		return NULL;
 750
 751	mutex_lock(&mdev_state->ops_lock);
 752	page = __mbochs_get_page(mdev_state, pgoff);
 753	mutex_unlock(&mdev_state->ops_lock);
 754
 755	return page;
 756}
 757
 758static void mbochs_put_pages(struct mdev_state *mdev_state)
 759{
 760	struct device *dev = mdev_dev(mdev_state->mdev);
 761	int i, count = 0;
 762
 763	WARN_ON(!mutex_is_locked(&mdev_state->ops_lock));
 764
 765	for (i = 0; i < mdev_state->pagecount; i++) {
 766		if (!mdev_state->pages[i])
 767			continue;
 768		put_page(mdev_state->pages[i]);
 769		mdev_state->pages[i] = NULL;
 770		count++;
 771	}
 772	dev_dbg(dev, "%s: %d pages released\n", __func__, count);
 773}
 774
 775static vm_fault_t mbochs_region_vm_fault(struct vm_fault *vmf)
 776{
 777	struct vm_area_struct *vma = vmf->vma;
 778	struct mdev_state *mdev_state = vma->vm_private_data;
 779	pgoff_t page_offset = (vmf->address - vma->vm_start) >> PAGE_SHIFT;
 780
 781	if (page_offset >= mdev_state->pagecount)
 782		return VM_FAULT_SIGBUS;
 783
 784	vmf->page = mbochs_get_page(mdev_state, page_offset);
 785	if (!vmf->page)
 786		return VM_FAULT_SIGBUS;
 787
 788	return 0;
 789}
 790
 791static const struct vm_operations_struct mbochs_region_vm_ops = {
 792	.fault = mbochs_region_vm_fault,
 793};
 794
 795static int mbochs_mmap(struct vfio_device *vdev, struct vm_area_struct *vma)
 796{
 797	struct mdev_state *mdev_state =
 798		container_of(vdev, struct mdev_state, vdev);
 799
 800	if (vma->vm_pgoff != MBOCHS_MEMORY_BAR_OFFSET >> PAGE_SHIFT)
 801		return -EINVAL;
 802	if (vma->vm_end < vma->vm_start)
 803		return -EINVAL;
 804	if (vma->vm_end - vma->vm_start > mdev_state->memsize)
 805		return -EINVAL;
 806	if ((vma->vm_flags & VM_SHARED) == 0)
 807		return -EINVAL;
 808
 809	vma->vm_ops = &mbochs_region_vm_ops;
 810	vma->vm_private_data = mdev_state;
 811	return 0;
 812}
 813
 814static vm_fault_t mbochs_dmabuf_vm_fault(struct vm_fault *vmf)
 815{
 816	struct vm_area_struct *vma = vmf->vma;
 817	struct mbochs_dmabuf *dmabuf = vma->vm_private_data;
 818
 819	if (WARN_ON(vmf->pgoff >= dmabuf->pagecount))
 820		return VM_FAULT_SIGBUS;
 821
 822	vmf->page = dmabuf->pages[vmf->pgoff];
 823	get_page(vmf->page);
 824	return 0;
 825}
 826
 827static const struct vm_operations_struct mbochs_dmabuf_vm_ops = {
 828	.fault = mbochs_dmabuf_vm_fault,
 829};
 830
 831static int mbochs_mmap_dmabuf(struct dma_buf *buf, struct vm_area_struct *vma)
 832{
 833	struct mbochs_dmabuf *dmabuf = buf->priv;
 834	struct device *dev = mdev_dev(dmabuf->mdev_state->mdev);
 835
 836	dev_dbg(dev, "%s: %d\n", __func__, dmabuf->id);
 837
 838	if ((vma->vm_flags & VM_SHARED) == 0)
 839		return -EINVAL;
 840
 841	vma->vm_ops = &mbochs_dmabuf_vm_ops;
 842	vma->vm_private_data = dmabuf;
 843	return 0;
 844}
 845
 846static void mbochs_print_dmabuf(struct mbochs_dmabuf *dmabuf,
 847				const char *prefix)
 848{
 849	struct device *dev = mdev_dev(dmabuf->mdev_state->mdev);
 850	u32 fourcc = dmabuf->mode.drm_format;
 851
 852	dev_dbg(dev, "%s/%d: %c%c%c%c, %dx%d, stride %d, off 0x%llx, size 0x%llx, pages %ld\n",
 853		prefix, dmabuf->id,
 854		fourcc ? ((fourcc >>  0) & 0xff) : '-',
 855		fourcc ? ((fourcc >>  8) & 0xff) : '-',
 856		fourcc ? ((fourcc >> 16) & 0xff) : '-',
 857		fourcc ? ((fourcc >> 24) & 0xff) : '-',
 858		dmabuf->mode.width, dmabuf->mode.height, dmabuf->mode.stride,
 859		dmabuf->mode.offset, dmabuf->mode.size, dmabuf->pagecount);
 860}
 861
 862static struct sg_table *mbochs_map_dmabuf(struct dma_buf_attachment *at,
 863					  enum dma_data_direction direction)
 864{
 865	struct mbochs_dmabuf *dmabuf = at->dmabuf->priv;
 866	struct device *dev = mdev_dev(dmabuf->mdev_state->mdev);
 867	struct sg_table *sg;
 868
 869	dev_dbg(dev, "%s: %d\n", __func__, dmabuf->id);
 870
 871	sg = kzalloc(sizeof(*sg), GFP_KERNEL);
 872	if (!sg)
 873		goto err1;
 874	if (sg_alloc_table_from_pages(sg, dmabuf->pages, dmabuf->pagecount,
 875				      0, dmabuf->mode.size, GFP_KERNEL) < 0)
 876		goto err2;
 877	if (dma_map_sgtable(at->dev, sg, direction, 0))
 878		goto err3;
 879
 880	return sg;
 881
 882err3:
 883	sg_free_table(sg);
 884err2:
 885	kfree(sg);
 886err1:
 887	return ERR_PTR(-ENOMEM);
 888}
 889
 890static void mbochs_unmap_dmabuf(struct dma_buf_attachment *at,
 891				struct sg_table *sg,
 892				enum dma_data_direction direction)
 893{
 894	struct mbochs_dmabuf *dmabuf = at->dmabuf->priv;
 895	struct device *dev = mdev_dev(dmabuf->mdev_state->mdev);
 896
 897	dev_dbg(dev, "%s: %d\n", __func__, dmabuf->id);
 898
 899	dma_unmap_sgtable(at->dev, sg, direction, 0);
 900	sg_free_table(sg);
 901	kfree(sg);
 902}
 903
 904static void mbochs_release_dmabuf(struct dma_buf *buf)
 905{
 906	struct mbochs_dmabuf *dmabuf = buf->priv;
 907	struct mdev_state *mdev_state = dmabuf->mdev_state;
 908	struct device *dev = mdev_dev(mdev_state->mdev);
 909	pgoff_t pg;
 910
 911	dev_dbg(dev, "%s: %d\n", __func__, dmabuf->id);
 912
 913	for (pg = 0; pg < dmabuf->pagecount; pg++)
 914		put_page(dmabuf->pages[pg]);
 915
 916	mutex_lock(&mdev_state->ops_lock);
 917	dmabuf->buf = NULL;
 918	if (dmabuf->unlinked)
 919		kfree(dmabuf);
 920	mutex_unlock(&mdev_state->ops_lock);
 921}
 922
 923static struct dma_buf_ops mbochs_dmabuf_ops = {
 924	.map_dma_buf	  = mbochs_map_dmabuf,
 925	.unmap_dma_buf	  = mbochs_unmap_dmabuf,
 926	.release	  = mbochs_release_dmabuf,
 927	.mmap		  = mbochs_mmap_dmabuf,
 928};
 929
 930static struct mbochs_dmabuf *mbochs_dmabuf_alloc(struct mdev_state *mdev_state,
 931						 struct mbochs_mode *mode)
 932{
 933	struct mbochs_dmabuf *dmabuf;
 934	pgoff_t page_offset, pg;
 935
 936	WARN_ON(!mutex_is_locked(&mdev_state->ops_lock));
 937
 938	dmabuf = kzalloc(sizeof(struct mbochs_dmabuf), GFP_KERNEL);
 939	if (!dmabuf)
 940		return NULL;
 941
 942	dmabuf->mode = *mode;
 943	dmabuf->id = mdev_state->next_id++;
 944	dmabuf->pagecount = DIV_ROUND_UP(mode->size, PAGE_SIZE);
 945	dmabuf->pages = kcalloc(dmabuf->pagecount, sizeof(struct page *),
 946				GFP_KERNEL);
 947	if (!dmabuf->pages)
 948		goto err_free_dmabuf;
 949
 950	page_offset = dmabuf->mode.offset >> PAGE_SHIFT;
 951	for (pg = 0; pg < dmabuf->pagecount; pg++) {
 952		dmabuf->pages[pg] = __mbochs_get_page(mdev_state,
 953						      page_offset + pg);
 954		if (!dmabuf->pages[pg])
 955			goto err_free_pages;
 956	}
 957
 958	dmabuf->mdev_state = mdev_state;
 959	list_add(&dmabuf->next, &mdev_state->dmabufs);
 960
 961	mbochs_print_dmabuf(dmabuf, __func__);
 962	return dmabuf;
 963
 964err_free_pages:
 965	while (pg > 0)
 966		put_page(dmabuf->pages[--pg]);
 967	kfree(dmabuf->pages);
 968err_free_dmabuf:
 969	kfree(dmabuf);
 970	return NULL;
 971}
 972
 973static struct mbochs_dmabuf *
 974mbochs_dmabuf_find_by_mode(struct mdev_state *mdev_state,
 975			   struct mbochs_mode *mode)
 976{
 977	struct mbochs_dmabuf *dmabuf;
 978
 979	WARN_ON(!mutex_is_locked(&mdev_state->ops_lock));
 980
 981	list_for_each_entry(dmabuf, &mdev_state->dmabufs, next)
 982		if (mbochs_modes_equal(&dmabuf->mode, mode))
 983			return dmabuf;
 984
 985	return NULL;
 986}
 987
 988static struct mbochs_dmabuf *
 989mbochs_dmabuf_find_by_id(struct mdev_state *mdev_state, u32 id)
 990{
 991	struct mbochs_dmabuf *dmabuf;
 992
 993	WARN_ON(!mutex_is_locked(&mdev_state->ops_lock));
 994
 995	list_for_each_entry(dmabuf, &mdev_state->dmabufs, next)
 996		if (dmabuf->id == id)
 997			return dmabuf;
 998
 999	return NULL;
1000}
1001
1002static int mbochs_dmabuf_export(struct mbochs_dmabuf *dmabuf)
1003{
1004	struct mdev_state *mdev_state = dmabuf->mdev_state;
1005	struct device *dev = mdev_state->vdev.dev;
1006	DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
1007	struct dma_buf *buf;
1008
1009	WARN_ON(!mutex_is_locked(&mdev_state->ops_lock));
1010
1011	if (!IS_ALIGNED(dmabuf->mode.offset, PAGE_SIZE)) {
1012		dev_info_ratelimited(dev, "%s: framebuffer not page-aligned\n",
1013				     __func__);
1014		return -EINVAL;
1015	}
1016
1017	exp_info.ops = &mbochs_dmabuf_ops;
1018	exp_info.size = dmabuf->mode.size;
1019	exp_info.priv = dmabuf;
1020
1021	buf = dma_buf_export(&exp_info);
1022	if (IS_ERR(buf)) {
1023		dev_info_ratelimited(dev, "%s: dma_buf_export failed: %ld\n",
1024				     __func__, PTR_ERR(buf));
1025		return PTR_ERR(buf);
1026	}
1027
1028	dmabuf->buf = buf;
1029	dev_dbg(dev, "%s: %d\n", __func__, dmabuf->id);
1030	return 0;
1031}
1032
1033static int mbochs_get_region_info(struct mdev_state *mdev_state,
1034				  struct vfio_region_info_ext *ext)
1035{
1036	struct vfio_region_info *region_info = &ext->base;
1037
1038	if (region_info->index >= MBOCHS_NUM_REGIONS)
1039		return -EINVAL;
1040
1041	switch (region_info->index) {
1042	case VFIO_PCI_CONFIG_REGION_INDEX:
1043		region_info->offset = 0;
1044		region_info->size   = MBOCHS_CONFIG_SPACE_SIZE;
1045		region_info->flags  = (VFIO_REGION_INFO_FLAG_READ |
1046				       VFIO_REGION_INFO_FLAG_WRITE);
1047		break;
1048	case VFIO_PCI_BAR0_REGION_INDEX:
1049		region_info->offset = MBOCHS_MEMORY_BAR_OFFSET;
1050		region_info->size   = mdev_state->memsize;
1051		region_info->flags  = (VFIO_REGION_INFO_FLAG_READ  |
1052				       VFIO_REGION_INFO_FLAG_WRITE |
1053				       VFIO_REGION_INFO_FLAG_MMAP);
1054		break;
1055	case VFIO_PCI_BAR2_REGION_INDEX:
1056		region_info->offset = MBOCHS_MMIO_BAR_OFFSET;
1057		region_info->size   = MBOCHS_MMIO_BAR_SIZE;
1058		region_info->flags  = (VFIO_REGION_INFO_FLAG_READ  |
1059				       VFIO_REGION_INFO_FLAG_WRITE);
1060		break;
1061	case MBOCHS_EDID_REGION_INDEX:
1062		ext->base.argsz = sizeof(*ext);
1063		ext->base.offset = MBOCHS_EDID_OFFSET;
1064		ext->base.size = MBOCHS_EDID_SIZE;
1065		ext->base.flags = (VFIO_REGION_INFO_FLAG_READ  |
1066				   VFIO_REGION_INFO_FLAG_WRITE |
1067				   VFIO_REGION_INFO_FLAG_CAPS);
1068		ext->base.cap_offset = offsetof(typeof(*ext), type);
1069		ext->type.header.id = VFIO_REGION_INFO_CAP_TYPE;
1070		ext->type.header.version = 1;
1071		ext->type.header.next = 0;
1072		ext->type.type = VFIO_REGION_TYPE_GFX;
1073		ext->type.subtype = VFIO_REGION_SUBTYPE_GFX_EDID;
1074		break;
1075	default:
1076		region_info->size   = 0;
1077		region_info->offset = 0;
1078		region_info->flags  = 0;
1079	}
1080
1081	return 0;
1082}
1083
1084static int mbochs_get_irq_info(struct vfio_irq_info *irq_info)
1085{
1086	irq_info->count = 0;
1087	return 0;
1088}
1089
1090static int mbochs_get_device_info(struct vfio_device_info *dev_info)
1091{
1092	dev_info->flags = VFIO_DEVICE_FLAGS_PCI;
1093	dev_info->num_regions = MBOCHS_NUM_REGIONS;
1094	dev_info->num_irqs = VFIO_PCI_NUM_IRQS;
1095	return 0;
1096}
1097
1098static int mbochs_query_gfx_plane(struct mdev_state *mdev_state,
1099				  struct vfio_device_gfx_plane_info *plane)
1100{
1101	struct mbochs_dmabuf *dmabuf;
1102	struct mbochs_mode mode;
1103	int ret;
1104
1105	if (plane->flags & VFIO_GFX_PLANE_TYPE_PROBE) {
1106		if (plane->flags == (VFIO_GFX_PLANE_TYPE_PROBE |
1107				     VFIO_GFX_PLANE_TYPE_DMABUF))
1108			return 0;
1109		return -EINVAL;
1110	}
1111
1112	if (plane->flags != VFIO_GFX_PLANE_TYPE_DMABUF)
1113		return -EINVAL;
1114
1115	plane->drm_format_mod = 0;
1116	plane->x_pos	      = 0;
1117	plane->y_pos	      = 0;
1118	plane->x_hot	      = 0;
1119	plane->y_hot	      = 0;
1120
1121	mutex_lock(&mdev_state->ops_lock);
1122
1123	ret = -EINVAL;
1124	if (plane->drm_plane_type == DRM_PLANE_TYPE_PRIMARY)
1125		ret = mbochs_check_framebuffer(mdev_state, &mode);
1126	if (ret < 0) {
1127		plane->drm_format     = 0;
1128		plane->width	      = 0;
1129		plane->height	      = 0;
1130		plane->stride	      = 0;
1131		plane->size	      = 0;
1132		plane->dmabuf_id      = 0;
1133		goto done;
1134	}
1135
1136	dmabuf = mbochs_dmabuf_find_by_mode(mdev_state, &mode);
1137	if (!dmabuf)
1138		mbochs_dmabuf_alloc(mdev_state, &mode);
1139	if (!dmabuf) {
1140		mutex_unlock(&mdev_state->ops_lock);
1141		return -ENOMEM;
1142	}
1143
1144	plane->drm_format     = dmabuf->mode.drm_format;
1145	plane->width	      = dmabuf->mode.width;
1146	plane->height	      = dmabuf->mode.height;
1147	plane->stride	      = dmabuf->mode.stride;
1148	plane->size	      = dmabuf->mode.size;
1149	plane->dmabuf_id      = dmabuf->id;
1150
1151done:
1152	if (plane->drm_plane_type == DRM_PLANE_TYPE_PRIMARY &&
1153	    mdev_state->active_id != plane->dmabuf_id) {
1154		dev_dbg(mdev_state->vdev.dev, "%s: primary: %d => %d\n",
1155			__func__, mdev_state->active_id, plane->dmabuf_id);
1156		mdev_state->active_id = plane->dmabuf_id;
1157	}
1158	mutex_unlock(&mdev_state->ops_lock);
1159	return 0;
1160}
1161
1162static int mbochs_get_gfx_dmabuf(struct mdev_state *mdev_state, u32 id)
1163{
1164	struct mbochs_dmabuf *dmabuf;
1165
1166	mutex_lock(&mdev_state->ops_lock);
1167
1168	dmabuf = mbochs_dmabuf_find_by_id(mdev_state, id);
1169	if (!dmabuf) {
1170		mutex_unlock(&mdev_state->ops_lock);
1171		return -ENOENT;
1172	}
1173
1174	if (!dmabuf->buf)
1175		mbochs_dmabuf_export(dmabuf);
1176
1177	mutex_unlock(&mdev_state->ops_lock);
1178
1179	if (!dmabuf->buf)
1180		return -EINVAL;
1181
1182	return dma_buf_fd(dmabuf->buf, 0);
1183}
1184
1185static long mbochs_ioctl(struct vfio_device *vdev, unsigned int cmd,
1186			 unsigned long arg)
1187{
1188	struct mdev_state *mdev_state =
1189		container_of(vdev, struct mdev_state, vdev);
1190	int ret = 0;
1191	unsigned long minsz, outsz;
1192
1193	switch (cmd) {
1194	case VFIO_DEVICE_GET_INFO:
1195	{
1196		struct vfio_device_info info;
1197
1198		minsz = offsetofend(struct vfio_device_info, num_irqs);
1199
1200		if (copy_from_user(&info, (void __user *)arg, minsz))
1201			return -EFAULT;
1202
1203		if (info.argsz < minsz)
1204			return -EINVAL;
1205
1206		ret = mbochs_get_device_info(&info);
1207		if (ret)
1208			return ret;
1209
1210		if (copy_to_user((void __user *)arg, &info, minsz))
1211			return -EFAULT;
1212
1213		return 0;
1214	}
1215	case VFIO_DEVICE_GET_REGION_INFO:
1216	{
1217		struct vfio_region_info_ext info;
1218
1219		minsz = offsetofend(typeof(info), base.offset);
1220
1221		if (copy_from_user(&info, (void __user *)arg, minsz))
1222			return -EFAULT;
1223
1224		outsz = info.base.argsz;
1225		if (outsz < minsz)
1226			return -EINVAL;
1227		if (outsz > sizeof(info))
1228			return -EINVAL;
1229
1230		ret = mbochs_get_region_info(mdev_state, &info);
1231		if (ret)
1232			return ret;
1233
1234		if (copy_to_user((void __user *)arg, &info, outsz))
1235			return -EFAULT;
1236
1237		return 0;
1238	}
1239
1240	case VFIO_DEVICE_GET_IRQ_INFO:
1241	{
1242		struct vfio_irq_info info;
1243
1244		minsz = offsetofend(struct vfio_irq_info, count);
1245
1246		if (copy_from_user(&info, (void __user *)arg, minsz))
1247			return -EFAULT;
1248
1249		if ((info.argsz < minsz) ||
1250		    (info.index >= VFIO_PCI_NUM_IRQS))
1251			return -EINVAL;
1252
1253		ret = mbochs_get_irq_info(&info);
1254		if (ret)
1255			return ret;
1256
1257		if (copy_to_user((void __user *)arg, &info, minsz))
1258			return -EFAULT;
1259
1260		return 0;
1261	}
1262
1263	case VFIO_DEVICE_QUERY_GFX_PLANE:
1264	{
1265		struct vfio_device_gfx_plane_info plane = {};
1266
1267		minsz = offsetofend(struct vfio_device_gfx_plane_info,
1268				    region_index);
1269
1270		if (copy_from_user(&plane, (void __user *)arg, minsz))
1271			return -EFAULT;
1272
1273		if (plane.argsz < minsz)
1274			return -EINVAL;
1275
1276		ret = mbochs_query_gfx_plane(mdev_state, &plane);
1277		if (ret)
1278			return ret;
1279
1280		if (copy_to_user((void __user *)arg, &plane, minsz))
1281			return -EFAULT;
1282
1283		return 0;
1284	}
1285
1286	case VFIO_DEVICE_GET_GFX_DMABUF:
1287	{
1288		u32 dmabuf_id;
1289
1290		if (get_user(dmabuf_id, (__u32 __user *)arg))
1291			return -EFAULT;
1292
1293		return mbochs_get_gfx_dmabuf(mdev_state, dmabuf_id);
1294	}
1295
1296	case VFIO_DEVICE_SET_IRQS:
1297		return -EINVAL;
1298
1299	case VFIO_DEVICE_RESET:
1300		return mbochs_reset(mdev_state);
1301	}
1302	return -ENOTTY;
1303}
1304
1305static void mbochs_close_device(struct vfio_device *vdev)
1306{
1307	struct mdev_state *mdev_state =
1308		container_of(vdev, struct mdev_state, vdev);
1309	struct mbochs_dmabuf *dmabuf, *tmp;
1310
1311	mutex_lock(&mdev_state->ops_lock);
1312
1313	list_for_each_entry_safe(dmabuf, tmp, &mdev_state->dmabufs, next) {
1314		list_del(&dmabuf->next);
1315		if (dmabuf->buf) {
1316			/* free in mbochs_release_dmabuf() */
1317			dmabuf->unlinked = true;
1318		} else {
1319			kfree(dmabuf);
1320		}
1321	}
1322	mbochs_put_pages(mdev_state);
1323
1324	mutex_unlock(&mdev_state->ops_lock);
1325}
1326
1327static ssize_t
1328memory_show(struct device *dev, struct device_attribute *attr,
1329	    char *buf)
1330{
1331	struct mdev_state *mdev_state = dev_get_drvdata(dev);
1332
1333	return sprintf(buf, "%d MB\n", mdev_state->type->mbytes);
1334}
1335static DEVICE_ATTR_RO(memory);
1336
1337static struct attribute *mdev_dev_attrs[] = {
1338	&dev_attr_memory.attr,
1339	NULL,
1340};
1341
1342static const struct attribute_group mdev_dev_group = {
1343	.name  = "vendor",
1344	.attrs = mdev_dev_attrs,
1345};
1346
1347static const struct attribute_group *mdev_dev_groups[] = {
1348	&mdev_dev_group,
1349	NULL,
1350};
1351
1352static ssize_t mbochs_show_description(struct mdev_type *mtype, char *buf)
1353{
1354	struct mbochs_type *type =
1355		container_of(mtype, struct mbochs_type, type);
1356
1357	return sprintf(buf, "virtual display, %d MB video memory\n",
1358		       type ? type->mbytes  : 0);
1359}
1360
1361static unsigned int mbochs_get_available(struct mdev_type *mtype)
1362{
1363	struct mbochs_type *type =
1364		container_of(mtype, struct mbochs_type, type);
1365
1366	return atomic_read(&mbochs_avail_mbytes) / type->mbytes;
1367}
1368
1369static const struct vfio_device_ops mbochs_dev_ops = {
1370	.close_device = mbochs_close_device,
1371	.init = mbochs_init_dev,
1372	.release = mbochs_release_dev,
1373	.read = mbochs_read,
1374	.write = mbochs_write,
1375	.ioctl = mbochs_ioctl,
1376	.mmap = mbochs_mmap,
1377	.bind_iommufd	= vfio_iommufd_emulated_bind,
1378	.unbind_iommufd	= vfio_iommufd_emulated_unbind,
1379	.attach_ioas	= vfio_iommufd_emulated_attach_ioas,
1380	.detach_ioas	= vfio_iommufd_emulated_detach_ioas,
1381};
1382
1383static struct mdev_driver mbochs_driver = {
1384	.device_api = VFIO_DEVICE_API_PCI_STRING,
1385	.driver = {
1386		.name = "mbochs",
1387		.owner = THIS_MODULE,
1388		.mod_name = KBUILD_MODNAME,
1389		.dev_groups = mdev_dev_groups,
1390	},
1391	.probe = mbochs_probe,
1392	.remove	= mbochs_remove,
1393	.get_available = mbochs_get_available,
1394	.show_description = mbochs_show_description,
1395};
1396
1397static const struct file_operations vd_fops = {
1398	.owner		= THIS_MODULE,
1399};
1400
1401static void mbochs_device_release(struct device *dev)
1402{
1403	/* nothing */
1404}
1405
1406static int __init mbochs_dev_init(void)
1407{
1408	int ret = 0;
1409
1410	atomic_set(&mbochs_avail_mbytes, max_mbytes);
1411
1412	ret = alloc_chrdev_region(&mbochs_devt, 0, MINORMASK + 1, MBOCHS_NAME);
1413	if (ret < 0) {
1414		pr_err("Error: failed to register mbochs_dev, err: %d\n", ret);
1415		return ret;
1416	}
1417	cdev_init(&mbochs_cdev, &vd_fops);
1418	cdev_add(&mbochs_cdev, mbochs_devt, MINORMASK + 1);
1419	pr_info("%s: major %d\n", __func__, MAJOR(mbochs_devt));
1420
1421	ret = mdev_register_driver(&mbochs_driver);
1422	if (ret)
1423		goto err_cdev;
1424
1425	mbochs_class = class_create(MBOCHS_CLASS_NAME);
1426	if (IS_ERR(mbochs_class)) {
1427		pr_err("Error: failed to register mbochs_dev class\n");
1428		ret = PTR_ERR(mbochs_class);
1429		goto err_driver;
1430	}
1431	mbochs_dev.class = mbochs_class;
1432	mbochs_dev.release = mbochs_device_release;
1433	dev_set_name(&mbochs_dev, "%s", MBOCHS_NAME);
1434
1435	ret = device_register(&mbochs_dev);
1436	if (ret)
1437		goto err_put;
1438
1439	ret = mdev_register_parent(&mbochs_parent, &mbochs_dev, &mbochs_driver,
1440				   mbochs_mdev_types,
1441				   ARRAY_SIZE(mbochs_mdev_types));
1442	if (ret)
1443		goto err_device;
1444
1445	return 0;
1446
1447err_device:
1448	device_del(&mbochs_dev);
1449err_put:
1450	put_device(&mbochs_dev);
1451	class_destroy(mbochs_class);
1452err_driver:
1453	mdev_unregister_driver(&mbochs_driver);
1454err_cdev:
1455	cdev_del(&mbochs_cdev);
1456	unregister_chrdev_region(mbochs_devt, MINORMASK + 1);
1457	return ret;
1458}
1459
1460static void __exit mbochs_dev_exit(void)
1461{
1462	mbochs_dev.bus = NULL;
1463	mdev_unregister_parent(&mbochs_parent);
1464
1465	device_unregister(&mbochs_dev);
1466	mdev_unregister_driver(&mbochs_driver);
1467	cdev_del(&mbochs_cdev);
1468	unregister_chrdev_region(mbochs_devt, MINORMASK + 1);
1469	class_destroy(mbochs_class);
1470	mbochs_class = NULL;
1471}
1472
1473MODULE_IMPORT_NS(DMA_BUF);
1474module_init(mbochs_dev_init)
1475module_exit(mbochs_dev_exit)
v6.9.4
   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/kernel.h>
  25#include <linux/slab.h>
  26#include <linux/vmalloc.h>
  27#include <linux/cdev.h>
  28#include <linux/vfio.h>
  29#include <linux/iommu.h>
  30#include <linux/sysfs.h>
  31#include <linux/mdev.h>
  32#include <linux/pci.h>
  33#include <linux/dma-buf.h>
  34#include <linux/highmem.h>
  35#include <drm/drm_fourcc.h>
  36#include <drm/drm_rect.h>
  37#include <drm/drm_modeset_lock.h>
  38#include <drm/drm_property.h>
  39#include <drm/drm_plane.h>
  40
  41
  42#define VBE_DISPI_INDEX_ID		0x0
  43#define VBE_DISPI_INDEX_XRES		0x1
  44#define VBE_DISPI_INDEX_YRES		0x2
  45#define VBE_DISPI_INDEX_BPP		0x3
  46#define VBE_DISPI_INDEX_ENABLE		0x4
  47#define VBE_DISPI_INDEX_BANK		0x5
  48#define VBE_DISPI_INDEX_VIRT_WIDTH	0x6
  49#define VBE_DISPI_INDEX_VIRT_HEIGHT	0x7
  50#define VBE_DISPI_INDEX_X_OFFSET	0x8
  51#define VBE_DISPI_INDEX_Y_OFFSET	0x9
  52#define VBE_DISPI_INDEX_VIDEO_MEMORY_64K 0xa
  53#define VBE_DISPI_INDEX_COUNT		0xb
  54
  55#define VBE_DISPI_ID0			0xB0C0
  56#define VBE_DISPI_ID1			0xB0C1
  57#define VBE_DISPI_ID2			0xB0C2
  58#define VBE_DISPI_ID3			0xB0C3
  59#define VBE_DISPI_ID4			0xB0C4
  60#define VBE_DISPI_ID5			0xB0C5
  61
  62#define VBE_DISPI_DISABLED		0x00
  63#define VBE_DISPI_ENABLED		0x01
  64#define VBE_DISPI_GETCAPS		0x02
  65#define VBE_DISPI_8BIT_DAC		0x20
  66#define VBE_DISPI_LFB_ENABLED		0x40
  67#define VBE_DISPI_NOCLEARMEM		0x80
  68
  69
  70#define MBOCHS_NAME		  "mbochs"
  71#define MBOCHS_CLASS_NAME	  "mbochs"
  72
  73#define MBOCHS_EDID_REGION_INDEX  VFIO_PCI_NUM_REGIONS
  74#define MBOCHS_NUM_REGIONS        (MBOCHS_EDID_REGION_INDEX+1)
  75
  76#define MBOCHS_CONFIG_SPACE_SIZE  0xff
  77#define MBOCHS_MMIO_BAR_OFFSET	  PAGE_SIZE
  78#define MBOCHS_MMIO_BAR_SIZE	  PAGE_SIZE
  79#define MBOCHS_EDID_OFFSET	  (MBOCHS_MMIO_BAR_OFFSET +	\
  80				   MBOCHS_MMIO_BAR_SIZE)
  81#define MBOCHS_EDID_SIZE	  PAGE_SIZE
  82#define MBOCHS_MEMORY_BAR_OFFSET  (MBOCHS_EDID_OFFSET + \
  83				   MBOCHS_EDID_SIZE)
  84
  85#define MBOCHS_EDID_BLOB_OFFSET   (MBOCHS_EDID_SIZE/2)
  86
  87#define STORE_LE16(addr, val)	(*(u16 *)addr = val)
  88#define STORE_LE32(addr, val)	(*(u32 *)addr = val)
  89
  90
  91MODULE_LICENSE("GPL v2");
  92
  93static int max_mbytes = 256;
  94module_param_named(count, max_mbytes, int, 0444);
  95MODULE_PARM_DESC(mem, "megabytes available to " MBOCHS_NAME " devices");
  96
  97
  98#define MBOCHS_TYPE_1 "small"
  99#define MBOCHS_TYPE_2 "medium"
 100#define MBOCHS_TYPE_3 "large"
 101
 102static struct mbochs_type {
 103	struct mdev_type type;
 104	u32 mbytes;
 105	u32 max_x;
 106	u32 max_y;
 107} mbochs_types[] = {
 108	{
 109		.type.sysfs_name	= MBOCHS_TYPE_1,
 110		.type.pretty_name	= MBOCHS_CLASS_NAME "-" MBOCHS_TYPE_1,
 111		.mbytes = 4,
 112		.max_x  = 800,
 113		.max_y  = 600,
 114	}, {
 115		.type.sysfs_name	= MBOCHS_TYPE_2,
 116		.type.pretty_name	= MBOCHS_CLASS_NAME "-" MBOCHS_TYPE_2,
 117		.mbytes = 16,
 118		.max_x  = 1920,
 119		.max_y  = 1440,
 120	}, {
 121		.type.sysfs_name	= MBOCHS_TYPE_3,
 122		.type.pretty_name	= MBOCHS_CLASS_NAME "-" MBOCHS_TYPE_3,
 123		.mbytes = 64,
 124		.max_x  = 0,
 125		.max_y  = 0,
 126	},
 127};
 128
 129static struct mdev_type *mbochs_mdev_types[] = {
 130	&mbochs_types[0].type,
 131	&mbochs_types[1].type,
 132	&mbochs_types[2].type,
 133};
 134
 135static dev_t		mbochs_devt;
 136static const struct class mbochs_class = {
 137	.name = MBOCHS_CLASS_NAME,
 138};
 139static struct cdev	mbochs_cdev;
 140static struct device	mbochs_dev;
 141static struct mdev_parent mbochs_parent;
 142static atomic_t mbochs_avail_mbytes;
 143static const struct vfio_device_ops mbochs_dev_ops;
 144
 145struct vfio_region_info_ext {
 146	struct vfio_region_info          base;
 147	struct vfio_region_info_cap_type type;
 148};
 149
 150struct mbochs_mode {
 151	u32 drm_format;
 152	u32 bytepp;
 153	u32 width;
 154	u32 height;
 155	u32 stride;
 156	u32 __pad;
 157	u64 offset;
 158	u64 size;
 159};
 160
 161struct mbochs_dmabuf {
 162	struct mbochs_mode mode;
 163	u32 id;
 164	struct page **pages;
 165	pgoff_t pagecount;
 166	struct dma_buf *buf;
 167	struct mdev_state *mdev_state;
 168	struct list_head next;
 169	bool unlinked;
 170};
 171
 172/* State of each mdev device */
 173struct mdev_state {
 174	struct vfio_device vdev;
 175	u8 *vconfig;
 176	u64 bar_mask[3];
 177	u32 memory_bar_mask;
 178	struct mutex ops_lock;
 179	struct mdev_device *mdev;
 180
 181	const struct mbochs_type *type;
 182	u16 vbe[VBE_DISPI_INDEX_COUNT];
 183	u64 memsize;
 184	struct page **pages;
 185	pgoff_t pagecount;
 186	struct vfio_region_gfx_edid edid_regs;
 187	u8 edid_blob[0x400];
 188
 189	struct list_head dmabufs;
 190	u32 active_id;
 191	u32 next_id;
 192};
 193
 194static const char *vbe_name_list[VBE_DISPI_INDEX_COUNT] = {
 195	[VBE_DISPI_INDEX_ID]               = "id",
 196	[VBE_DISPI_INDEX_XRES]             = "xres",
 197	[VBE_DISPI_INDEX_YRES]             = "yres",
 198	[VBE_DISPI_INDEX_BPP]              = "bpp",
 199	[VBE_DISPI_INDEX_ENABLE]           = "enable",
 200	[VBE_DISPI_INDEX_BANK]             = "bank",
 201	[VBE_DISPI_INDEX_VIRT_WIDTH]       = "virt-width",
 202	[VBE_DISPI_INDEX_VIRT_HEIGHT]      = "virt-height",
 203	[VBE_DISPI_INDEX_X_OFFSET]         = "x-offset",
 204	[VBE_DISPI_INDEX_Y_OFFSET]         = "y-offset",
 205	[VBE_DISPI_INDEX_VIDEO_MEMORY_64K] = "video-mem",
 206};
 207
 208static const char *vbe_name(u32 index)
 209{
 210	if (index < ARRAY_SIZE(vbe_name_list))
 211		return vbe_name_list[index];
 212	return "(invalid)";
 213}
 214
 215static struct page *__mbochs_get_page(struct mdev_state *mdev_state,
 216				      pgoff_t pgoff);
 217static struct page *mbochs_get_page(struct mdev_state *mdev_state,
 218				    pgoff_t pgoff);
 219
 220static void mbochs_create_config_space(struct mdev_state *mdev_state)
 221{
 222	STORE_LE16((u16 *) &mdev_state->vconfig[PCI_VENDOR_ID],
 223		   0x1234);
 224	STORE_LE16((u16 *) &mdev_state->vconfig[PCI_DEVICE_ID],
 225		   0x1111);
 226	STORE_LE16((u16 *) &mdev_state->vconfig[PCI_SUBSYSTEM_VENDOR_ID],
 227		   PCI_SUBVENDOR_ID_REDHAT_QUMRANET);
 228	STORE_LE16((u16 *) &mdev_state->vconfig[PCI_SUBSYSTEM_ID],
 229		   PCI_SUBDEVICE_ID_QEMU);
 230
 231	STORE_LE16((u16 *) &mdev_state->vconfig[PCI_COMMAND],
 232		   PCI_COMMAND_IO | PCI_COMMAND_MEMORY);
 233	STORE_LE16((u16 *) &mdev_state->vconfig[PCI_CLASS_DEVICE],
 234		   PCI_CLASS_DISPLAY_OTHER);
 235	mdev_state->vconfig[PCI_CLASS_REVISION] =  0x01;
 236
 237	STORE_LE32((u32 *) &mdev_state->vconfig[PCI_BASE_ADDRESS_0],
 238		   PCI_BASE_ADDRESS_SPACE_MEMORY |
 239		   PCI_BASE_ADDRESS_MEM_TYPE_32	 |
 240		   PCI_BASE_ADDRESS_MEM_PREFETCH);
 241	mdev_state->bar_mask[0] = ~(mdev_state->memsize) + 1;
 242
 243	STORE_LE32((u32 *) &mdev_state->vconfig[PCI_BASE_ADDRESS_2],
 244		   PCI_BASE_ADDRESS_SPACE_MEMORY |
 245		   PCI_BASE_ADDRESS_MEM_TYPE_32);
 246	mdev_state->bar_mask[2] = ~(MBOCHS_MMIO_BAR_SIZE) + 1;
 247}
 248
 249static int mbochs_check_framebuffer(struct mdev_state *mdev_state,
 250				    struct mbochs_mode *mode)
 251{
 252	struct device *dev = mdev_dev(mdev_state->mdev);
 253	u16 *vbe = mdev_state->vbe;
 254	u32 virt_width;
 255
 256	WARN_ON(!mutex_is_locked(&mdev_state->ops_lock));
 257
 258	if (!(vbe[VBE_DISPI_INDEX_ENABLE] & VBE_DISPI_ENABLED))
 259		goto nofb;
 260
 261	memset(mode, 0, sizeof(*mode));
 262	switch (vbe[VBE_DISPI_INDEX_BPP]) {
 263	case 32:
 264		mode->drm_format = DRM_FORMAT_XRGB8888;
 265		mode->bytepp = 4;
 266		break;
 267	default:
 268		dev_info_ratelimited(dev, "%s: bpp %d not supported\n",
 269				     __func__, vbe[VBE_DISPI_INDEX_BPP]);
 270		goto nofb;
 271	}
 272
 273	mode->width  = vbe[VBE_DISPI_INDEX_XRES];
 274	mode->height = vbe[VBE_DISPI_INDEX_YRES];
 275	virt_width  = vbe[VBE_DISPI_INDEX_VIRT_WIDTH];
 276	if (virt_width < mode->width)
 277		virt_width = mode->width;
 278	mode->stride = virt_width * mode->bytepp;
 279	mode->size   = (u64)mode->stride * mode->height;
 280	mode->offset = ((u64)vbe[VBE_DISPI_INDEX_X_OFFSET] * mode->bytepp +
 281		       (u64)vbe[VBE_DISPI_INDEX_Y_OFFSET] * mode->stride);
 282
 283	if (mode->width < 64 || mode->height < 64) {
 284		dev_info_ratelimited(dev, "%s: invalid resolution %dx%d\n",
 285				     __func__, mode->width, mode->height);
 286		goto nofb;
 287	}
 288	if (mode->offset + mode->size > mdev_state->memsize) {
 289		dev_info_ratelimited(dev, "%s: framebuffer memory overflow\n",
 290				     __func__);
 291		goto nofb;
 292	}
 293
 294	return 0;
 295
 296nofb:
 297	memset(mode, 0, sizeof(*mode));
 298	return -EINVAL;
 299}
 300
 301static bool mbochs_modes_equal(struct mbochs_mode *mode1,
 302			       struct mbochs_mode *mode2)
 303{
 304	return memcmp(mode1, mode2, sizeof(struct mbochs_mode)) == 0;
 305}
 306
 307static void handle_pci_cfg_write(struct mdev_state *mdev_state, u16 offset,
 308				 char *buf, u32 count)
 309{
 310	struct device *dev = mdev_dev(mdev_state->mdev);
 311	int index = (offset - PCI_BASE_ADDRESS_0) / 0x04;
 312	u32 cfg_addr;
 313
 314	switch (offset) {
 315	case PCI_BASE_ADDRESS_0:
 316	case PCI_BASE_ADDRESS_2:
 317		cfg_addr = *(u32 *)buf;
 318
 319		if (cfg_addr == 0xffffffff) {
 320			cfg_addr = (cfg_addr & mdev_state->bar_mask[index]);
 321		} else {
 322			cfg_addr &= PCI_BASE_ADDRESS_MEM_MASK;
 323			if (cfg_addr)
 324				dev_info(dev, "BAR #%d @ 0x%x\n",
 325					 index, cfg_addr);
 326		}
 327
 328		cfg_addr |= (mdev_state->vconfig[offset] &
 329			     ~PCI_BASE_ADDRESS_MEM_MASK);
 330		STORE_LE32(&mdev_state->vconfig[offset], cfg_addr);
 331		break;
 332	}
 333}
 334
 335static void handle_mmio_write(struct mdev_state *mdev_state, u16 offset,
 336			      char *buf, u32 count)
 337{
 338	struct device *dev = mdev_dev(mdev_state->mdev);
 339	int index;
 340	u16 reg16;
 341
 342	switch (offset) {
 343	case 0x400 ... 0x41f: /* vga ioports remapped */
 344		goto unhandled;
 345	case 0x500 ... 0x515: /* bochs dispi interface */
 346		if (count != 2)
 347			goto unhandled;
 348		index = (offset - 0x500) / 2;
 349		reg16 = *(u16 *)buf;
 350		if (index < ARRAY_SIZE(mdev_state->vbe))
 351			mdev_state->vbe[index] = reg16;
 352		dev_dbg(dev, "%s: vbe write %d = %d (%s)\n",
 353			__func__, index, reg16, vbe_name(index));
 354		break;
 355	case 0x600 ... 0x607: /* qemu extended regs */
 356		goto unhandled;
 357	default:
 358unhandled:
 359		dev_dbg(dev, "%s: @0x%03x, count %d (unhandled)\n",
 360			__func__, offset, count);
 361		break;
 362	}
 363}
 364
 365static void handle_mmio_read(struct mdev_state *mdev_state, u16 offset,
 366			     char *buf, u32 count)
 367{
 368	struct device *dev = mdev_dev(mdev_state->mdev);
 369	struct vfio_region_gfx_edid *edid;
 370	u16 reg16 = 0;
 371	int index;
 372
 373	switch (offset) {
 374	case 0x000 ... 0x3ff: /* edid block */
 375		edid = &mdev_state->edid_regs;
 376		if (edid->link_state != VFIO_DEVICE_GFX_LINK_STATE_UP ||
 377		    offset >= edid->edid_size) {
 378			memset(buf, 0, count);
 379			break;
 380		}
 381		memcpy(buf, mdev_state->edid_blob + offset, count);
 382		break;
 383	case 0x500 ... 0x515: /* bochs dispi interface */
 384		if (count != 2)
 385			goto unhandled;
 386		index = (offset - 0x500) / 2;
 387		if (index < ARRAY_SIZE(mdev_state->vbe))
 388			reg16 = mdev_state->vbe[index];
 389		dev_dbg(dev, "%s: vbe read %d = %d (%s)\n",
 390			__func__, index, reg16, vbe_name(index));
 391		*(u16 *)buf = reg16;
 392		break;
 393	default:
 394unhandled:
 395		dev_dbg(dev, "%s: @0x%03x, count %d (unhandled)\n",
 396			__func__, offset, count);
 397		memset(buf, 0, count);
 398		break;
 399	}
 400}
 401
 402static void handle_edid_regs(struct mdev_state *mdev_state, u16 offset,
 403			     char *buf, u32 count, bool is_write)
 404{
 405	char *regs = (void *)&mdev_state->edid_regs;
 406
 407	if (offset + count > sizeof(mdev_state->edid_regs))
 408		return;
 409	if (count != 4)
 410		return;
 411	if (offset % 4)
 412		return;
 413
 414	if (is_write) {
 415		switch (offset) {
 416		case offsetof(struct vfio_region_gfx_edid, link_state):
 417		case offsetof(struct vfio_region_gfx_edid, edid_size):
 418			memcpy(regs + offset, buf, count);
 419			break;
 420		default:
 421			/* read-only regs */
 422			break;
 423		}
 424	} else {
 425		memcpy(buf, regs + offset, count);
 426	}
 427}
 428
 429static void handle_edid_blob(struct mdev_state *mdev_state, u16 offset,
 430			     char *buf, u32 count, bool is_write)
 431{
 432	if (offset + count > mdev_state->edid_regs.edid_max_size)
 433		return;
 434	if (is_write)
 435		memcpy(mdev_state->edid_blob + offset, buf, count);
 436	else
 437		memcpy(buf, mdev_state->edid_blob + offset, count);
 438}
 439
 440static ssize_t mdev_access(struct mdev_state *mdev_state, char *buf,
 441			   size_t count, loff_t pos, bool is_write)
 442{
 443	struct page *pg;
 444	loff_t poff;
 445	char *map;
 446	int ret = 0;
 447
 448	mutex_lock(&mdev_state->ops_lock);
 449
 450	if (pos < MBOCHS_CONFIG_SPACE_SIZE) {
 451		if (is_write)
 452			handle_pci_cfg_write(mdev_state, pos, buf, count);
 453		else
 454			memcpy(buf, (mdev_state->vconfig + pos), count);
 455
 456	} else if (pos >= MBOCHS_MMIO_BAR_OFFSET &&
 457		   pos + count <= (MBOCHS_MMIO_BAR_OFFSET +
 458				   MBOCHS_MMIO_BAR_SIZE)) {
 459		pos -= MBOCHS_MMIO_BAR_OFFSET;
 460		if (is_write)
 461			handle_mmio_write(mdev_state, pos, buf, count);
 462		else
 463			handle_mmio_read(mdev_state, pos, buf, count);
 464
 465	} else if (pos >= MBOCHS_EDID_OFFSET &&
 466		   pos + count <= (MBOCHS_EDID_OFFSET +
 467				   MBOCHS_EDID_SIZE)) {
 468		pos -= MBOCHS_EDID_OFFSET;
 469		if (pos < MBOCHS_EDID_BLOB_OFFSET) {
 470			handle_edid_regs(mdev_state, pos, buf, count, is_write);
 471		} else {
 472			pos -= MBOCHS_EDID_BLOB_OFFSET;
 473			handle_edid_blob(mdev_state, pos, buf, count, is_write);
 474		}
 475
 476	} else if (pos >= MBOCHS_MEMORY_BAR_OFFSET &&
 477		   pos + count <=
 478		   MBOCHS_MEMORY_BAR_OFFSET + mdev_state->memsize) {
 479		pos -= MBOCHS_MMIO_BAR_OFFSET;
 480		poff = pos & ~PAGE_MASK;
 481		pg = __mbochs_get_page(mdev_state, pos >> PAGE_SHIFT);
 482		map = kmap(pg);
 483		if (is_write)
 484			memcpy(map + poff, buf, count);
 485		else
 486			memcpy(buf, map + poff, count);
 487		kunmap(pg);
 488		put_page(pg);
 489
 490	} else {
 491		dev_dbg(mdev_state->vdev.dev, "%s: %s @0x%llx (unhandled)\n",
 492			__func__, is_write ? "WR" : "RD", pos);
 493		ret = -1;
 494		goto accessfailed;
 495	}
 496
 497	ret = count;
 498
 499
 500accessfailed:
 501	mutex_unlock(&mdev_state->ops_lock);
 502
 503	return ret;
 504}
 505
 506static int mbochs_reset(struct mdev_state *mdev_state)
 507{
 508	u32 size64k = mdev_state->memsize / (64 * 1024);
 509	int i;
 510
 511	for (i = 0; i < ARRAY_SIZE(mdev_state->vbe); i++)
 512		mdev_state->vbe[i] = 0;
 513	mdev_state->vbe[VBE_DISPI_INDEX_ID] = VBE_DISPI_ID5;
 514	mdev_state->vbe[VBE_DISPI_INDEX_VIDEO_MEMORY_64K] = size64k;
 515	return 0;
 516}
 517
 518static int mbochs_init_dev(struct vfio_device *vdev)
 519{
 520	struct mdev_state *mdev_state =
 521		container_of(vdev, struct mdev_state, vdev);
 522	struct mdev_device *mdev = to_mdev_device(vdev->dev);
 523	struct mbochs_type *type =
 524		container_of(mdev->type, struct mbochs_type, type);
 525	int avail_mbytes = atomic_read(&mbochs_avail_mbytes);
 526	int ret = -ENOMEM;
 527
 528	do {
 529		if (avail_mbytes < type->mbytes)
 530			return -ENOSPC;
 531	} while (!atomic_try_cmpxchg(&mbochs_avail_mbytes, &avail_mbytes,
 532				     avail_mbytes - type->mbytes));
 533
 534	mdev_state->vconfig = kzalloc(MBOCHS_CONFIG_SPACE_SIZE, GFP_KERNEL);
 535	if (!mdev_state->vconfig)
 536		goto err_avail;
 537
 538	mdev_state->memsize = type->mbytes * 1024 * 1024;
 539	mdev_state->pagecount = mdev_state->memsize >> PAGE_SHIFT;
 540	mdev_state->pages = kcalloc(mdev_state->pagecount,
 541				    sizeof(struct page *),
 542				    GFP_KERNEL);
 543	if (!mdev_state->pages)
 544		goto err_vconfig;
 545
 546	mutex_init(&mdev_state->ops_lock);
 547	mdev_state->mdev = mdev;
 548	INIT_LIST_HEAD(&mdev_state->dmabufs);
 549	mdev_state->next_id = 1;
 550
 551	mdev_state->type = type;
 552	mdev_state->edid_regs.max_xres = type->max_x;
 553	mdev_state->edid_regs.max_yres = type->max_y;
 554	mdev_state->edid_regs.edid_offset = MBOCHS_EDID_BLOB_OFFSET;
 555	mdev_state->edid_regs.edid_max_size = sizeof(mdev_state->edid_blob);
 556	mbochs_create_config_space(mdev_state);
 557	mbochs_reset(mdev_state);
 558
 559	dev_info(vdev->dev, "%s: %s, %d MB, %ld pages\n", __func__,
 560		 type->type.pretty_name, type->mbytes, mdev_state->pagecount);
 561	return 0;
 562
 563err_vconfig:
 564	kfree(mdev_state->vconfig);
 565err_avail:
 566	atomic_add(type->mbytes, &mbochs_avail_mbytes);
 567	return ret;
 568}
 569
 570static int mbochs_probe(struct mdev_device *mdev)
 571{
 572	struct mdev_state *mdev_state;
 573	int ret = -ENOMEM;
 574
 575	mdev_state = vfio_alloc_device(mdev_state, vdev, &mdev->dev,
 576				       &mbochs_dev_ops);
 577	if (IS_ERR(mdev_state))
 578		return PTR_ERR(mdev_state);
 579
 580	ret = vfio_register_emulated_iommu_dev(&mdev_state->vdev);
 581	if (ret)
 582		goto err_put_vdev;
 583	dev_set_drvdata(&mdev->dev, mdev_state);
 584	return 0;
 585
 586err_put_vdev:
 587	vfio_put_device(&mdev_state->vdev);
 588	return ret;
 589}
 590
 591static void mbochs_release_dev(struct vfio_device *vdev)
 592{
 593	struct mdev_state *mdev_state =
 594		container_of(vdev, struct mdev_state, vdev);
 595
 596	atomic_add(mdev_state->type->mbytes, &mbochs_avail_mbytes);
 597	kfree(mdev_state->pages);
 598	kfree(mdev_state->vconfig);
 599}
 600
 601static void mbochs_remove(struct mdev_device *mdev)
 602{
 603	struct mdev_state *mdev_state = dev_get_drvdata(&mdev->dev);
 604
 605	vfio_unregister_group_dev(&mdev_state->vdev);
 606	vfio_put_device(&mdev_state->vdev);
 607}
 608
 609static ssize_t mbochs_read(struct vfio_device *vdev, char __user *buf,
 610			   size_t count, loff_t *ppos)
 611{
 612	struct mdev_state *mdev_state =
 613		container_of(vdev, struct mdev_state, vdev);
 614	unsigned int done = 0;
 615	int ret;
 616
 617	while (count) {
 618		size_t filled;
 619
 620		if (count >= 4 && !(*ppos % 4)) {
 621			u32 val;
 622
 623			ret =  mdev_access(mdev_state, (char *)&val, sizeof(val),
 624					   *ppos, false);
 625			if (ret <= 0)
 626				goto read_err;
 627
 628			if (copy_to_user(buf, &val, sizeof(val)))
 629				goto read_err;
 630
 631			filled = 4;
 632		} else if (count >= 2 && !(*ppos % 2)) {
 633			u16 val;
 634
 635			ret = mdev_access(mdev_state, (char *)&val, sizeof(val),
 636					  *ppos, false);
 637			if (ret <= 0)
 638				goto read_err;
 639
 640			if (copy_to_user(buf, &val, sizeof(val)))
 641				goto read_err;
 642
 643			filled = 2;
 644		} else {
 645			u8 val;
 646
 647			ret = mdev_access(mdev_state, (char *)&val, sizeof(val),
 648					  *ppos, false);
 649			if (ret <= 0)
 650				goto read_err;
 651
 652			if (copy_to_user(buf, &val, sizeof(val)))
 653				goto read_err;
 654
 655			filled = 1;
 656		}
 657
 658		count -= filled;
 659		done += filled;
 660		*ppos += filled;
 661		buf += filled;
 662	}
 663
 664	return done;
 665
 666read_err:
 667	return -EFAULT;
 668}
 669
 670static ssize_t mbochs_write(struct vfio_device *vdev, const char __user *buf,
 671			    size_t count, loff_t *ppos)
 672{
 673	struct mdev_state *mdev_state =
 674		container_of(vdev, struct mdev_state, vdev);
 675	unsigned int done = 0;
 676	int ret;
 677
 678	while (count) {
 679		size_t filled;
 680
 681		if (count >= 4 && !(*ppos % 4)) {
 682			u32 val;
 683
 684			if (copy_from_user(&val, buf, sizeof(val)))
 685				goto write_err;
 686
 687			ret = mdev_access(mdev_state, (char *)&val, sizeof(val),
 688					  *ppos, true);
 689			if (ret <= 0)
 690				goto write_err;
 691
 692			filled = 4;
 693		} else if (count >= 2 && !(*ppos % 2)) {
 694			u16 val;
 695
 696			if (copy_from_user(&val, buf, sizeof(val)))
 697				goto write_err;
 698
 699			ret = mdev_access(mdev_state, (char *)&val, sizeof(val),
 700					  *ppos, true);
 701			if (ret <= 0)
 702				goto write_err;
 703
 704			filled = 2;
 705		} else {
 706			u8 val;
 707
 708			if (copy_from_user(&val, buf, sizeof(val)))
 709				goto write_err;
 710
 711			ret = mdev_access(mdev_state, (char *)&val, sizeof(val),
 712					  *ppos, true);
 713			if (ret <= 0)
 714				goto write_err;
 715
 716			filled = 1;
 717		}
 718		count -= filled;
 719		done += filled;
 720		*ppos += filled;
 721		buf += filled;
 722	}
 723
 724	return done;
 725write_err:
 726	return -EFAULT;
 727}
 728
 729static struct page *__mbochs_get_page(struct mdev_state *mdev_state,
 730				      pgoff_t pgoff)
 731{
 732	WARN_ON(!mutex_is_locked(&mdev_state->ops_lock));
 733
 734	if (!mdev_state->pages[pgoff]) {
 735		mdev_state->pages[pgoff] =
 736			alloc_pages(GFP_HIGHUSER | __GFP_ZERO, 0);
 737		if (!mdev_state->pages[pgoff])
 738			return NULL;
 739	}
 740
 741	get_page(mdev_state->pages[pgoff]);
 742	return mdev_state->pages[pgoff];
 743}
 744
 745static struct page *mbochs_get_page(struct mdev_state *mdev_state,
 746				    pgoff_t pgoff)
 747{
 748	struct page *page;
 749
 750	if (WARN_ON(pgoff >= mdev_state->pagecount))
 751		return NULL;
 752
 753	mutex_lock(&mdev_state->ops_lock);
 754	page = __mbochs_get_page(mdev_state, pgoff);
 755	mutex_unlock(&mdev_state->ops_lock);
 756
 757	return page;
 758}
 759
 760static void mbochs_put_pages(struct mdev_state *mdev_state)
 761{
 762	struct device *dev = mdev_dev(mdev_state->mdev);
 763	int i, count = 0;
 764
 765	WARN_ON(!mutex_is_locked(&mdev_state->ops_lock));
 766
 767	for (i = 0; i < mdev_state->pagecount; i++) {
 768		if (!mdev_state->pages[i])
 769			continue;
 770		put_page(mdev_state->pages[i]);
 771		mdev_state->pages[i] = NULL;
 772		count++;
 773	}
 774	dev_dbg(dev, "%s: %d pages released\n", __func__, count);
 775}
 776
 777static vm_fault_t mbochs_region_vm_fault(struct vm_fault *vmf)
 778{
 779	struct vm_area_struct *vma = vmf->vma;
 780	struct mdev_state *mdev_state = vma->vm_private_data;
 781	pgoff_t page_offset = (vmf->address - vma->vm_start) >> PAGE_SHIFT;
 782
 783	if (page_offset >= mdev_state->pagecount)
 784		return VM_FAULT_SIGBUS;
 785
 786	vmf->page = mbochs_get_page(mdev_state, page_offset);
 787	if (!vmf->page)
 788		return VM_FAULT_SIGBUS;
 789
 790	return 0;
 791}
 792
 793static const struct vm_operations_struct mbochs_region_vm_ops = {
 794	.fault = mbochs_region_vm_fault,
 795};
 796
 797static int mbochs_mmap(struct vfio_device *vdev, struct vm_area_struct *vma)
 798{
 799	struct mdev_state *mdev_state =
 800		container_of(vdev, struct mdev_state, vdev);
 801
 802	if (vma->vm_pgoff != MBOCHS_MEMORY_BAR_OFFSET >> PAGE_SHIFT)
 803		return -EINVAL;
 804	if (vma->vm_end < vma->vm_start)
 805		return -EINVAL;
 806	if (vma->vm_end - vma->vm_start > mdev_state->memsize)
 807		return -EINVAL;
 808	if ((vma->vm_flags & VM_SHARED) == 0)
 809		return -EINVAL;
 810
 811	vma->vm_ops = &mbochs_region_vm_ops;
 812	vma->vm_private_data = mdev_state;
 813	return 0;
 814}
 815
 816static vm_fault_t mbochs_dmabuf_vm_fault(struct vm_fault *vmf)
 817{
 818	struct vm_area_struct *vma = vmf->vma;
 819	struct mbochs_dmabuf *dmabuf = vma->vm_private_data;
 820
 821	if (WARN_ON(vmf->pgoff >= dmabuf->pagecount))
 822		return VM_FAULT_SIGBUS;
 823
 824	vmf->page = dmabuf->pages[vmf->pgoff];
 825	get_page(vmf->page);
 826	return 0;
 827}
 828
 829static const struct vm_operations_struct mbochs_dmabuf_vm_ops = {
 830	.fault = mbochs_dmabuf_vm_fault,
 831};
 832
 833static int mbochs_mmap_dmabuf(struct dma_buf *buf, struct vm_area_struct *vma)
 834{
 835	struct mbochs_dmabuf *dmabuf = buf->priv;
 836	struct device *dev = mdev_dev(dmabuf->mdev_state->mdev);
 837
 838	dev_dbg(dev, "%s: %d\n", __func__, dmabuf->id);
 839
 840	if ((vma->vm_flags & VM_SHARED) == 0)
 841		return -EINVAL;
 842
 843	vma->vm_ops = &mbochs_dmabuf_vm_ops;
 844	vma->vm_private_data = dmabuf;
 845	return 0;
 846}
 847
 848static void mbochs_print_dmabuf(struct mbochs_dmabuf *dmabuf,
 849				const char *prefix)
 850{
 851	struct device *dev = mdev_dev(dmabuf->mdev_state->mdev);
 852	u32 fourcc = dmabuf->mode.drm_format;
 853
 854	dev_dbg(dev, "%s/%d: %c%c%c%c, %dx%d, stride %d, off 0x%llx, size 0x%llx, pages %ld\n",
 855		prefix, dmabuf->id,
 856		fourcc ? ((fourcc >>  0) & 0xff) : '-',
 857		fourcc ? ((fourcc >>  8) & 0xff) : '-',
 858		fourcc ? ((fourcc >> 16) & 0xff) : '-',
 859		fourcc ? ((fourcc >> 24) & 0xff) : '-',
 860		dmabuf->mode.width, dmabuf->mode.height, dmabuf->mode.stride,
 861		dmabuf->mode.offset, dmabuf->mode.size, dmabuf->pagecount);
 862}
 863
 864static struct sg_table *mbochs_map_dmabuf(struct dma_buf_attachment *at,
 865					  enum dma_data_direction direction)
 866{
 867	struct mbochs_dmabuf *dmabuf = at->dmabuf->priv;
 868	struct device *dev = mdev_dev(dmabuf->mdev_state->mdev);
 869	struct sg_table *sg;
 870
 871	dev_dbg(dev, "%s: %d\n", __func__, dmabuf->id);
 872
 873	sg = kzalloc(sizeof(*sg), GFP_KERNEL);
 874	if (!sg)
 875		goto err1;
 876	if (sg_alloc_table_from_pages(sg, dmabuf->pages, dmabuf->pagecount,
 877				      0, dmabuf->mode.size, GFP_KERNEL) < 0)
 878		goto err2;
 879	if (dma_map_sgtable(at->dev, sg, direction, 0))
 880		goto err3;
 881
 882	return sg;
 883
 884err3:
 885	sg_free_table(sg);
 886err2:
 887	kfree(sg);
 888err1:
 889	return ERR_PTR(-ENOMEM);
 890}
 891
 892static void mbochs_unmap_dmabuf(struct dma_buf_attachment *at,
 893				struct sg_table *sg,
 894				enum dma_data_direction direction)
 895{
 896	struct mbochs_dmabuf *dmabuf = at->dmabuf->priv;
 897	struct device *dev = mdev_dev(dmabuf->mdev_state->mdev);
 898
 899	dev_dbg(dev, "%s: %d\n", __func__, dmabuf->id);
 900
 901	dma_unmap_sgtable(at->dev, sg, direction, 0);
 902	sg_free_table(sg);
 903	kfree(sg);
 904}
 905
 906static void mbochs_release_dmabuf(struct dma_buf *buf)
 907{
 908	struct mbochs_dmabuf *dmabuf = buf->priv;
 909	struct mdev_state *mdev_state = dmabuf->mdev_state;
 910	struct device *dev = mdev_dev(mdev_state->mdev);
 911	pgoff_t pg;
 912
 913	dev_dbg(dev, "%s: %d\n", __func__, dmabuf->id);
 914
 915	for (pg = 0; pg < dmabuf->pagecount; pg++)
 916		put_page(dmabuf->pages[pg]);
 917
 918	mutex_lock(&mdev_state->ops_lock);
 919	dmabuf->buf = NULL;
 920	if (dmabuf->unlinked)
 921		kfree(dmabuf);
 922	mutex_unlock(&mdev_state->ops_lock);
 923}
 924
 925static struct dma_buf_ops mbochs_dmabuf_ops = {
 926	.map_dma_buf	  = mbochs_map_dmabuf,
 927	.unmap_dma_buf	  = mbochs_unmap_dmabuf,
 928	.release	  = mbochs_release_dmabuf,
 929	.mmap		  = mbochs_mmap_dmabuf,
 930};
 931
 932static struct mbochs_dmabuf *mbochs_dmabuf_alloc(struct mdev_state *mdev_state,
 933						 struct mbochs_mode *mode)
 934{
 935	struct mbochs_dmabuf *dmabuf;
 936	pgoff_t page_offset, pg;
 937
 938	WARN_ON(!mutex_is_locked(&mdev_state->ops_lock));
 939
 940	dmabuf = kzalloc(sizeof(struct mbochs_dmabuf), GFP_KERNEL);
 941	if (!dmabuf)
 942		return NULL;
 943
 944	dmabuf->mode = *mode;
 945	dmabuf->id = mdev_state->next_id++;
 946	dmabuf->pagecount = DIV_ROUND_UP(mode->size, PAGE_SIZE);
 947	dmabuf->pages = kcalloc(dmabuf->pagecount, sizeof(struct page *),
 948				GFP_KERNEL);
 949	if (!dmabuf->pages)
 950		goto err_free_dmabuf;
 951
 952	page_offset = dmabuf->mode.offset >> PAGE_SHIFT;
 953	for (pg = 0; pg < dmabuf->pagecount; pg++) {
 954		dmabuf->pages[pg] = __mbochs_get_page(mdev_state,
 955						      page_offset + pg);
 956		if (!dmabuf->pages[pg])
 957			goto err_free_pages;
 958	}
 959
 960	dmabuf->mdev_state = mdev_state;
 961	list_add(&dmabuf->next, &mdev_state->dmabufs);
 962
 963	mbochs_print_dmabuf(dmabuf, __func__);
 964	return dmabuf;
 965
 966err_free_pages:
 967	while (pg > 0)
 968		put_page(dmabuf->pages[--pg]);
 969	kfree(dmabuf->pages);
 970err_free_dmabuf:
 971	kfree(dmabuf);
 972	return NULL;
 973}
 974
 975static struct mbochs_dmabuf *
 976mbochs_dmabuf_find_by_mode(struct mdev_state *mdev_state,
 977			   struct mbochs_mode *mode)
 978{
 979	struct mbochs_dmabuf *dmabuf;
 980
 981	WARN_ON(!mutex_is_locked(&mdev_state->ops_lock));
 982
 983	list_for_each_entry(dmabuf, &mdev_state->dmabufs, next)
 984		if (mbochs_modes_equal(&dmabuf->mode, mode))
 985			return dmabuf;
 986
 987	return NULL;
 988}
 989
 990static struct mbochs_dmabuf *
 991mbochs_dmabuf_find_by_id(struct mdev_state *mdev_state, u32 id)
 992{
 993	struct mbochs_dmabuf *dmabuf;
 994
 995	WARN_ON(!mutex_is_locked(&mdev_state->ops_lock));
 996
 997	list_for_each_entry(dmabuf, &mdev_state->dmabufs, next)
 998		if (dmabuf->id == id)
 999			return dmabuf;
1000
1001	return NULL;
1002}
1003
1004static int mbochs_dmabuf_export(struct mbochs_dmabuf *dmabuf)
1005{
1006	struct mdev_state *mdev_state = dmabuf->mdev_state;
1007	struct device *dev = mdev_state->vdev.dev;
1008	DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
1009	struct dma_buf *buf;
1010
1011	WARN_ON(!mutex_is_locked(&mdev_state->ops_lock));
1012
1013	if (!IS_ALIGNED(dmabuf->mode.offset, PAGE_SIZE)) {
1014		dev_info_ratelimited(dev, "%s: framebuffer not page-aligned\n",
1015				     __func__);
1016		return -EINVAL;
1017	}
1018
1019	exp_info.ops = &mbochs_dmabuf_ops;
1020	exp_info.size = dmabuf->mode.size;
1021	exp_info.priv = dmabuf;
1022
1023	buf = dma_buf_export(&exp_info);
1024	if (IS_ERR(buf)) {
1025		dev_info_ratelimited(dev, "%s: dma_buf_export failed: %ld\n",
1026				     __func__, PTR_ERR(buf));
1027		return PTR_ERR(buf);
1028	}
1029
1030	dmabuf->buf = buf;
1031	dev_dbg(dev, "%s: %d\n", __func__, dmabuf->id);
1032	return 0;
1033}
1034
1035static int mbochs_get_region_info(struct mdev_state *mdev_state,
1036				  struct vfio_region_info_ext *ext)
1037{
1038	struct vfio_region_info *region_info = &ext->base;
1039
1040	if (region_info->index >= MBOCHS_NUM_REGIONS)
1041		return -EINVAL;
1042
1043	switch (region_info->index) {
1044	case VFIO_PCI_CONFIG_REGION_INDEX:
1045		region_info->offset = 0;
1046		region_info->size   = MBOCHS_CONFIG_SPACE_SIZE;
1047		region_info->flags  = (VFIO_REGION_INFO_FLAG_READ |
1048				       VFIO_REGION_INFO_FLAG_WRITE);
1049		break;
1050	case VFIO_PCI_BAR0_REGION_INDEX:
1051		region_info->offset = MBOCHS_MEMORY_BAR_OFFSET;
1052		region_info->size   = mdev_state->memsize;
1053		region_info->flags  = (VFIO_REGION_INFO_FLAG_READ  |
1054				       VFIO_REGION_INFO_FLAG_WRITE |
1055				       VFIO_REGION_INFO_FLAG_MMAP);
1056		break;
1057	case VFIO_PCI_BAR2_REGION_INDEX:
1058		region_info->offset = MBOCHS_MMIO_BAR_OFFSET;
1059		region_info->size   = MBOCHS_MMIO_BAR_SIZE;
1060		region_info->flags  = (VFIO_REGION_INFO_FLAG_READ  |
1061				       VFIO_REGION_INFO_FLAG_WRITE);
1062		break;
1063	case MBOCHS_EDID_REGION_INDEX:
1064		ext->base.argsz = sizeof(*ext);
1065		ext->base.offset = MBOCHS_EDID_OFFSET;
1066		ext->base.size = MBOCHS_EDID_SIZE;
1067		ext->base.flags = (VFIO_REGION_INFO_FLAG_READ  |
1068				   VFIO_REGION_INFO_FLAG_WRITE |
1069				   VFIO_REGION_INFO_FLAG_CAPS);
1070		ext->base.cap_offset = offsetof(typeof(*ext), type);
1071		ext->type.header.id = VFIO_REGION_INFO_CAP_TYPE;
1072		ext->type.header.version = 1;
1073		ext->type.header.next = 0;
1074		ext->type.type = VFIO_REGION_TYPE_GFX;
1075		ext->type.subtype = VFIO_REGION_SUBTYPE_GFX_EDID;
1076		break;
1077	default:
1078		region_info->size   = 0;
1079		region_info->offset = 0;
1080		region_info->flags  = 0;
1081	}
1082
1083	return 0;
1084}
1085
1086static int mbochs_get_irq_info(struct vfio_irq_info *irq_info)
1087{
1088	irq_info->count = 0;
1089	return 0;
1090}
1091
1092static int mbochs_get_device_info(struct vfio_device_info *dev_info)
1093{
1094	dev_info->flags = VFIO_DEVICE_FLAGS_PCI;
1095	dev_info->num_regions = MBOCHS_NUM_REGIONS;
1096	dev_info->num_irqs = VFIO_PCI_NUM_IRQS;
1097	return 0;
1098}
1099
1100static int mbochs_query_gfx_plane(struct mdev_state *mdev_state,
1101				  struct vfio_device_gfx_plane_info *plane)
1102{
1103	struct mbochs_dmabuf *dmabuf;
1104	struct mbochs_mode mode;
1105	int ret;
1106
1107	if (plane->flags & VFIO_GFX_PLANE_TYPE_PROBE) {
1108		if (plane->flags == (VFIO_GFX_PLANE_TYPE_PROBE |
1109				     VFIO_GFX_PLANE_TYPE_DMABUF))
1110			return 0;
1111		return -EINVAL;
1112	}
1113
1114	if (plane->flags != VFIO_GFX_PLANE_TYPE_DMABUF)
1115		return -EINVAL;
1116
1117	plane->drm_format_mod = 0;
1118	plane->x_pos	      = 0;
1119	plane->y_pos	      = 0;
1120	plane->x_hot	      = 0;
1121	plane->y_hot	      = 0;
1122
1123	mutex_lock(&mdev_state->ops_lock);
1124
1125	ret = -EINVAL;
1126	if (plane->drm_plane_type == DRM_PLANE_TYPE_PRIMARY)
1127		ret = mbochs_check_framebuffer(mdev_state, &mode);
1128	if (ret < 0) {
1129		plane->drm_format     = 0;
1130		plane->width	      = 0;
1131		plane->height	      = 0;
1132		plane->stride	      = 0;
1133		plane->size	      = 0;
1134		plane->dmabuf_id      = 0;
1135		goto done;
1136	}
1137
1138	dmabuf = mbochs_dmabuf_find_by_mode(mdev_state, &mode);
1139	if (!dmabuf)
1140		mbochs_dmabuf_alloc(mdev_state, &mode);
1141	if (!dmabuf) {
1142		mutex_unlock(&mdev_state->ops_lock);
1143		return -ENOMEM;
1144	}
1145
1146	plane->drm_format     = dmabuf->mode.drm_format;
1147	plane->width	      = dmabuf->mode.width;
1148	plane->height	      = dmabuf->mode.height;
1149	plane->stride	      = dmabuf->mode.stride;
1150	plane->size	      = dmabuf->mode.size;
1151	plane->dmabuf_id      = dmabuf->id;
1152
1153done:
1154	if (plane->drm_plane_type == DRM_PLANE_TYPE_PRIMARY &&
1155	    mdev_state->active_id != plane->dmabuf_id) {
1156		dev_dbg(mdev_state->vdev.dev, "%s: primary: %d => %d\n",
1157			__func__, mdev_state->active_id, plane->dmabuf_id);
1158		mdev_state->active_id = plane->dmabuf_id;
1159	}
1160	mutex_unlock(&mdev_state->ops_lock);
1161	return 0;
1162}
1163
1164static int mbochs_get_gfx_dmabuf(struct mdev_state *mdev_state, u32 id)
1165{
1166	struct mbochs_dmabuf *dmabuf;
1167
1168	mutex_lock(&mdev_state->ops_lock);
1169
1170	dmabuf = mbochs_dmabuf_find_by_id(mdev_state, id);
1171	if (!dmabuf) {
1172		mutex_unlock(&mdev_state->ops_lock);
1173		return -ENOENT;
1174	}
1175
1176	if (!dmabuf->buf)
1177		mbochs_dmabuf_export(dmabuf);
1178
1179	mutex_unlock(&mdev_state->ops_lock);
1180
1181	if (!dmabuf->buf)
1182		return -EINVAL;
1183
1184	return dma_buf_fd(dmabuf->buf, 0);
1185}
1186
1187static long mbochs_ioctl(struct vfio_device *vdev, unsigned int cmd,
1188			 unsigned long arg)
1189{
1190	struct mdev_state *mdev_state =
1191		container_of(vdev, struct mdev_state, vdev);
1192	int ret = 0;
1193	unsigned long minsz, outsz;
1194
1195	switch (cmd) {
1196	case VFIO_DEVICE_GET_INFO:
1197	{
1198		struct vfio_device_info info;
1199
1200		minsz = offsetofend(struct vfio_device_info, num_irqs);
1201
1202		if (copy_from_user(&info, (void __user *)arg, minsz))
1203			return -EFAULT;
1204
1205		if (info.argsz < minsz)
1206			return -EINVAL;
1207
1208		ret = mbochs_get_device_info(&info);
1209		if (ret)
1210			return ret;
1211
1212		if (copy_to_user((void __user *)arg, &info, minsz))
1213			return -EFAULT;
1214
1215		return 0;
1216	}
1217	case VFIO_DEVICE_GET_REGION_INFO:
1218	{
1219		struct vfio_region_info_ext info;
1220
1221		minsz = offsetofend(typeof(info), base.offset);
1222
1223		if (copy_from_user(&info, (void __user *)arg, minsz))
1224			return -EFAULT;
1225
1226		outsz = info.base.argsz;
1227		if (outsz < minsz)
1228			return -EINVAL;
1229		if (outsz > sizeof(info))
1230			return -EINVAL;
1231
1232		ret = mbochs_get_region_info(mdev_state, &info);
1233		if (ret)
1234			return ret;
1235
1236		if (copy_to_user((void __user *)arg, &info, outsz))
1237			return -EFAULT;
1238
1239		return 0;
1240	}
1241
1242	case VFIO_DEVICE_GET_IRQ_INFO:
1243	{
1244		struct vfio_irq_info info;
1245
1246		minsz = offsetofend(struct vfio_irq_info, count);
1247
1248		if (copy_from_user(&info, (void __user *)arg, minsz))
1249			return -EFAULT;
1250
1251		if ((info.argsz < minsz) ||
1252		    (info.index >= VFIO_PCI_NUM_IRQS))
1253			return -EINVAL;
1254
1255		ret = mbochs_get_irq_info(&info);
1256		if (ret)
1257			return ret;
1258
1259		if (copy_to_user((void __user *)arg, &info, minsz))
1260			return -EFAULT;
1261
1262		return 0;
1263	}
1264
1265	case VFIO_DEVICE_QUERY_GFX_PLANE:
1266	{
1267		struct vfio_device_gfx_plane_info plane = {};
1268
1269		minsz = offsetofend(struct vfio_device_gfx_plane_info,
1270				    region_index);
1271
1272		if (copy_from_user(&plane, (void __user *)arg, minsz))
1273			return -EFAULT;
1274
1275		if (plane.argsz < minsz)
1276			return -EINVAL;
1277
1278		ret = mbochs_query_gfx_plane(mdev_state, &plane);
1279		if (ret)
1280			return ret;
1281
1282		if (copy_to_user((void __user *)arg, &plane, minsz))
1283			return -EFAULT;
1284
1285		return 0;
1286	}
1287
1288	case VFIO_DEVICE_GET_GFX_DMABUF:
1289	{
1290		u32 dmabuf_id;
1291
1292		if (get_user(dmabuf_id, (__u32 __user *)arg))
1293			return -EFAULT;
1294
1295		return mbochs_get_gfx_dmabuf(mdev_state, dmabuf_id);
1296	}
1297
1298	case VFIO_DEVICE_SET_IRQS:
1299		return -EINVAL;
1300
1301	case VFIO_DEVICE_RESET:
1302		return mbochs_reset(mdev_state);
1303	}
1304	return -ENOTTY;
1305}
1306
1307static void mbochs_close_device(struct vfio_device *vdev)
1308{
1309	struct mdev_state *mdev_state =
1310		container_of(vdev, struct mdev_state, vdev);
1311	struct mbochs_dmabuf *dmabuf, *tmp;
1312
1313	mutex_lock(&mdev_state->ops_lock);
1314
1315	list_for_each_entry_safe(dmabuf, tmp, &mdev_state->dmabufs, next) {
1316		list_del(&dmabuf->next);
1317		if (dmabuf->buf) {
1318			/* free in mbochs_release_dmabuf() */
1319			dmabuf->unlinked = true;
1320		} else {
1321			kfree(dmabuf);
1322		}
1323	}
1324	mbochs_put_pages(mdev_state);
1325
1326	mutex_unlock(&mdev_state->ops_lock);
1327}
1328
1329static ssize_t
1330memory_show(struct device *dev, struct device_attribute *attr,
1331	    char *buf)
1332{
1333	struct mdev_state *mdev_state = dev_get_drvdata(dev);
1334
1335	return sprintf(buf, "%d MB\n", mdev_state->type->mbytes);
1336}
1337static DEVICE_ATTR_RO(memory);
1338
1339static struct attribute *mdev_dev_attrs[] = {
1340	&dev_attr_memory.attr,
1341	NULL,
1342};
1343
1344static const struct attribute_group mdev_dev_group = {
1345	.name  = "vendor",
1346	.attrs = mdev_dev_attrs,
1347};
1348
1349static const struct attribute_group *mdev_dev_groups[] = {
1350	&mdev_dev_group,
1351	NULL,
1352};
1353
1354static ssize_t mbochs_show_description(struct mdev_type *mtype, char *buf)
1355{
1356	struct mbochs_type *type =
1357		container_of(mtype, struct mbochs_type, type);
1358
1359	return sprintf(buf, "virtual display, %d MB video memory\n",
1360		       type ? type->mbytes  : 0);
1361}
1362
1363static unsigned int mbochs_get_available(struct mdev_type *mtype)
1364{
1365	struct mbochs_type *type =
1366		container_of(mtype, struct mbochs_type, type);
1367
1368	return atomic_read(&mbochs_avail_mbytes) / type->mbytes;
1369}
1370
1371static const struct vfio_device_ops mbochs_dev_ops = {
1372	.close_device = mbochs_close_device,
1373	.init = mbochs_init_dev,
1374	.release = mbochs_release_dev,
1375	.read = mbochs_read,
1376	.write = mbochs_write,
1377	.ioctl = mbochs_ioctl,
1378	.mmap = mbochs_mmap,
1379	.bind_iommufd	= vfio_iommufd_emulated_bind,
1380	.unbind_iommufd	= vfio_iommufd_emulated_unbind,
1381	.attach_ioas	= vfio_iommufd_emulated_attach_ioas,
1382	.detach_ioas	= vfio_iommufd_emulated_detach_ioas,
1383};
1384
1385static struct mdev_driver mbochs_driver = {
1386	.device_api = VFIO_DEVICE_API_PCI_STRING,
1387	.driver = {
1388		.name = "mbochs",
1389		.owner = THIS_MODULE,
1390		.mod_name = KBUILD_MODNAME,
1391		.dev_groups = mdev_dev_groups,
1392	},
1393	.probe = mbochs_probe,
1394	.remove	= mbochs_remove,
1395	.get_available = mbochs_get_available,
1396	.show_description = mbochs_show_description,
1397};
1398
1399static const struct file_operations vd_fops = {
1400	.owner		= THIS_MODULE,
1401};
1402
1403static void mbochs_device_release(struct device *dev)
1404{
1405	/* nothing */
1406}
1407
1408static int __init mbochs_dev_init(void)
1409{
1410	int ret = 0;
1411
1412	atomic_set(&mbochs_avail_mbytes, max_mbytes);
1413
1414	ret = alloc_chrdev_region(&mbochs_devt, 0, MINORMASK + 1, MBOCHS_NAME);
1415	if (ret < 0) {
1416		pr_err("Error: failed to register mbochs_dev, err: %d\n", ret);
1417		return ret;
1418	}
1419	cdev_init(&mbochs_cdev, &vd_fops);
1420	cdev_add(&mbochs_cdev, mbochs_devt, MINORMASK + 1);
1421	pr_info("%s: major %d\n", __func__, MAJOR(mbochs_devt));
1422
1423	ret = mdev_register_driver(&mbochs_driver);
1424	if (ret)
1425		goto err_cdev;
1426
1427	ret = class_register(&mbochs_class);
1428	if (ret)
 
 
1429		goto err_driver;
1430	mbochs_dev.class = &mbochs_class;
 
1431	mbochs_dev.release = mbochs_device_release;
1432	dev_set_name(&mbochs_dev, "%s", MBOCHS_NAME);
1433
1434	ret = device_register(&mbochs_dev);
1435	if (ret)
1436		goto err_put;
1437
1438	ret = mdev_register_parent(&mbochs_parent, &mbochs_dev, &mbochs_driver,
1439				   mbochs_mdev_types,
1440				   ARRAY_SIZE(mbochs_mdev_types));
1441	if (ret)
1442		goto err_device;
1443
1444	return 0;
1445
1446err_device:
1447	device_del(&mbochs_dev);
1448err_put:
1449	put_device(&mbochs_dev);
1450	class_unregister(&mbochs_class);
1451err_driver:
1452	mdev_unregister_driver(&mbochs_driver);
1453err_cdev:
1454	cdev_del(&mbochs_cdev);
1455	unregister_chrdev_region(mbochs_devt, MINORMASK + 1);
1456	return ret;
1457}
1458
1459static void __exit mbochs_dev_exit(void)
1460{
1461	mbochs_dev.bus = NULL;
1462	mdev_unregister_parent(&mbochs_parent);
1463
1464	device_unregister(&mbochs_dev);
1465	mdev_unregister_driver(&mbochs_driver);
1466	cdev_del(&mbochs_cdev);
1467	unregister_chrdev_region(mbochs_devt, MINORMASK + 1);
1468	class_unregister(&mbochs_class);
 
1469}
1470
1471MODULE_IMPORT_NS(DMA_BUF);
1472module_init(mbochs_dev_init)
1473module_exit(mbochs_dev_exit)