samples/vfio-mdev/mbochs.c

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