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TOMOYO Linux Cross Reference
Linux/samples/vfio-mdev/mbochs.c

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

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