-
Notifications
You must be signed in to change notification settings - Fork 102
/
mbochs.c
1505 lines (1243 loc) · 36.4 KB
/
mbochs.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
// SPDX-License-Identifier: GPL-2.0
/*
* Mediated virtual PCI display host device driver
*
* Emulate enough of qemu stdvga to make bochs-drm.ko happy. That is
* basically the vram memory bar and the bochs dispi interface vbe
* registers in the mmio register bar. Specifically it does *not*
* include any legacy vga stuff. Device looks a lot like "qemu -device
* secondary-vga".
*
* (c) Gerd Hoffmann <kraxel@redhat.com>
*
* based on mtty driver which is:
* Copyright (c) 2016, NVIDIA CORPORATION. All rights reserved.
* Author: Neo Jia <cjia@nvidia.com>
* Kirti Wankhede <kwankhede@nvidia.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/init.h>
#include <linux/module.h>
#include <linux/device.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <linux/cdev.h>
#include <linux/vfio.h>
#include <linux/iommu.h>
#include <linux/sysfs.h>
#include <linux/mdev.h>
#include <linux/pci.h>
#include <linux/dma-buf.h>
#include <linux/highmem.h>
#include <drm/drm_fourcc.h>
#include <drm/drm_rect.h>
#include <drm/drm_modeset_lock.h>
#include <drm/drm_property.h>
#include <drm/drm_plane.h>
#define VBE_DISPI_INDEX_ID 0x0
#define VBE_DISPI_INDEX_XRES 0x1
#define VBE_DISPI_INDEX_YRES 0x2
#define VBE_DISPI_INDEX_BPP 0x3
#define VBE_DISPI_INDEX_ENABLE 0x4
#define VBE_DISPI_INDEX_BANK 0x5
#define VBE_DISPI_INDEX_VIRT_WIDTH 0x6
#define VBE_DISPI_INDEX_VIRT_HEIGHT 0x7
#define VBE_DISPI_INDEX_X_OFFSET 0x8
#define VBE_DISPI_INDEX_Y_OFFSET 0x9
#define VBE_DISPI_INDEX_VIDEO_MEMORY_64K 0xa
#define VBE_DISPI_INDEX_COUNT 0xb
#define VBE_DISPI_ID0 0xB0C0
#define VBE_DISPI_ID1 0xB0C1
#define VBE_DISPI_ID2 0xB0C2
#define VBE_DISPI_ID3 0xB0C3
#define VBE_DISPI_ID4 0xB0C4
#define VBE_DISPI_ID5 0xB0C5
#define VBE_DISPI_DISABLED 0x00
#define VBE_DISPI_ENABLED 0x01
#define VBE_DISPI_GETCAPS 0x02
#define VBE_DISPI_8BIT_DAC 0x20
#define VBE_DISPI_LFB_ENABLED 0x40
#define VBE_DISPI_NOCLEARMEM 0x80
#define MBOCHS_NAME "mbochs"
#define MBOCHS_CLASS_NAME "mbochs"
#define MBOCHS_EDID_REGION_INDEX VFIO_PCI_NUM_REGIONS
#define MBOCHS_NUM_REGIONS (MBOCHS_EDID_REGION_INDEX+1)
#define MBOCHS_CONFIG_SPACE_SIZE 0xff
#define MBOCHS_MMIO_BAR_OFFSET PAGE_SIZE
#define MBOCHS_MMIO_BAR_SIZE PAGE_SIZE
#define MBOCHS_EDID_OFFSET (MBOCHS_MMIO_BAR_OFFSET + \
MBOCHS_MMIO_BAR_SIZE)
#define MBOCHS_EDID_SIZE PAGE_SIZE
#define MBOCHS_MEMORY_BAR_OFFSET (MBOCHS_EDID_OFFSET + \
MBOCHS_EDID_SIZE)
#define MBOCHS_EDID_BLOB_OFFSET (MBOCHS_EDID_SIZE/2)
#define STORE_LE16(addr, val) (*(u16 *)addr = val)
#define STORE_LE32(addr, val) (*(u32 *)addr = val)
MODULE_LICENSE("GPL v2");
static int max_mbytes = 256;
module_param_named(count, max_mbytes, int, 0444);
MODULE_PARM_DESC(mem, "megabytes available to " MBOCHS_NAME " devices");
#define MBOCHS_TYPE_1 "small"
#define MBOCHS_TYPE_2 "medium"
#define MBOCHS_TYPE_3 "large"
static const struct mbochs_type {
const char *name;
u32 mbytes;
u32 max_x;
u32 max_y;
} mbochs_types[] = {
{
.name = MBOCHS_CLASS_NAME "-" MBOCHS_TYPE_1,
.mbytes = 4,
.max_x = 800,
.max_y = 600,
}, {
.name = MBOCHS_CLASS_NAME "-" MBOCHS_TYPE_2,
.mbytes = 16,
.max_x = 1920,
.max_y = 1440,
}, {
.name = MBOCHS_CLASS_NAME "-" MBOCHS_TYPE_3,
.mbytes = 64,
.max_x = 0,
.max_y = 0,
},
};
static dev_t mbochs_devt;
static struct class *mbochs_class;
static struct cdev mbochs_cdev;
static struct device mbochs_dev;
static atomic_t mbochs_avail_mbytes;
static const struct vfio_device_ops mbochs_dev_ops;
struct vfio_region_info_ext {
struct vfio_region_info base;
struct vfio_region_info_cap_type type;
};
struct mbochs_mode {
u32 drm_format;
u32 bytepp;
u32 width;
u32 height;
u32 stride;
u32 __pad;
u64 offset;
u64 size;
};
struct mbochs_dmabuf {
struct mbochs_mode mode;
u32 id;
struct page **pages;
pgoff_t pagecount;
struct dma_buf *buf;
struct mdev_state *mdev_state;
struct list_head next;
bool unlinked;
};
/* State of each mdev device */
struct mdev_state {
struct vfio_device vdev;
u8 *vconfig;
u64 bar_mask[3];
u32 memory_bar_mask;
struct mutex ops_lock;
struct mdev_device *mdev;
const struct mbochs_type *type;
u16 vbe[VBE_DISPI_INDEX_COUNT];
u64 memsize;
struct page **pages;
pgoff_t pagecount;
struct vfio_region_gfx_edid edid_regs;
u8 edid_blob[0x400];
struct list_head dmabufs;
u32 active_id;
u32 next_id;
};
static const char *vbe_name_list[VBE_DISPI_INDEX_COUNT] = {
[VBE_DISPI_INDEX_ID] = "id",
[VBE_DISPI_INDEX_XRES] = "xres",
[VBE_DISPI_INDEX_YRES] = "yres",
[VBE_DISPI_INDEX_BPP] = "bpp",
[VBE_DISPI_INDEX_ENABLE] = "enable",
[VBE_DISPI_INDEX_BANK] = "bank",
[VBE_DISPI_INDEX_VIRT_WIDTH] = "virt-width",
[VBE_DISPI_INDEX_VIRT_HEIGHT] = "virt-height",
[VBE_DISPI_INDEX_X_OFFSET] = "x-offset",
[VBE_DISPI_INDEX_Y_OFFSET] = "y-offset",
[VBE_DISPI_INDEX_VIDEO_MEMORY_64K] = "video-mem",
};
static const char *vbe_name(u32 index)
{
if (index < ARRAY_SIZE(vbe_name_list))
return vbe_name_list[index];
return "(invalid)";
}
static struct page *__mbochs_get_page(struct mdev_state *mdev_state,
pgoff_t pgoff);
static struct page *mbochs_get_page(struct mdev_state *mdev_state,
pgoff_t pgoff);
static void mbochs_create_config_space(struct mdev_state *mdev_state)
{
STORE_LE16((u16 *) &mdev_state->vconfig[PCI_VENDOR_ID],
0x1234);
STORE_LE16((u16 *) &mdev_state->vconfig[PCI_DEVICE_ID],
0x1111);
STORE_LE16((u16 *) &mdev_state->vconfig[PCI_SUBSYSTEM_VENDOR_ID],
PCI_SUBVENDOR_ID_REDHAT_QUMRANET);
STORE_LE16((u16 *) &mdev_state->vconfig[PCI_SUBSYSTEM_ID],
PCI_SUBDEVICE_ID_QEMU);
STORE_LE16((u16 *) &mdev_state->vconfig[PCI_COMMAND],
PCI_COMMAND_IO | PCI_COMMAND_MEMORY);
STORE_LE16((u16 *) &mdev_state->vconfig[PCI_CLASS_DEVICE],
PCI_CLASS_DISPLAY_OTHER);
mdev_state->vconfig[PCI_CLASS_REVISION] = 0x01;
STORE_LE32((u32 *) &mdev_state->vconfig[PCI_BASE_ADDRESS_0],
PCI_BASE_ADDRESS_SPACE_MEMORY |
PCI_BASE_ADDRESS_MEM_TYPE_32 |
PCI_BASE_ADDRESS_MEM_PREFETCH);
mdev_state->bar_mask[0] = ~(mdev_state->memsize) + 1;
STORE_LE32((u32 *) &mdev_state->vconfig[PCI_BASE_ADDRESS_2],
PCI_BASE_ADDRESS_SPACE_MEMORY |
PCI_BASE_ADDRESS_MEM_TYPE_32);
mdev_state->bar_mask[2] = ~(MBOCHS_MMIO_BAR_SIZE) + 1;
}
static int mbochs_check_framebuffer(struct mdev_state *mdev_state,
struct mbochs_mode *mode)
{
struct device *dev = mdev_dev(mdev_state->mdev);
u16 *vbe = mdev_state->vbe;
u32 virt_width;
WARN_ON(!mutex_is_locked(&mdev_state->ops_lock));
if (!(vbe[VBE_DISPI_INDEX_ENABLE] & VBE_DISPI_ENABLED))
goto nofb;
memset(mode, 0, sizeof(*mode));
switch (vbe[VBE_DISPI_INDEX_BPP]) {
case 32:
mode->drm_format = DRM_FORMAT_XRGB8888;
mode->bytepp = 4;
break;
default:
dev_info_ratelimited(dev, "%s: bpp %d not supported\n",
__func__, vbe[VBE_DISPI_INDEX_BPP]);
goto nofb;
}
mode->width = vbe[VBE_DISPI_INDEX_XRES];
mode->height = vbe[VBE_DISPI_INDEX_YRES];
virt_width = vbe[VBE_DISPI_INDEX_VIRT_WIDTH];
if (virt_width < mode->width)
virt_width = mode->width;
mode->stride = virt_width * mode->bytepp;
mode->size = (u64)mode->stride * mode->height;
mode->offset = ((u64)vbe[VBE_DISPI_INDEX_X_OFFSET] * mode->bytepp +
(u64)vbe[VBE_DISPI_INDEX_Y_OFFSET] * mode->stride);
if (mode->width < 64 || mode->height < 64) {
dev_info_ratelimited(dev, "%s: invalid resolution %dx%d\n",
__func__, mode->width, mode->height);
goto nofb;
}
if (mode->offset + mode->size > mdev_state->memsize) {
dev_info_ratelimited(dev, "%s: framebuffer memory overflow\n",
__func__);
goto nofb;
}
return 0;
nofb:
memset(mode, 0, sizeof(*mode));
return -EINVAL;
}
static bool mbochs_modes_equal(struct mbochs_mode *mode1,
struct mbochs_mode *mode2)
{
return memcmp(mode1, mode2, sizeof(struct mbochs_mode)) == 0;
}
static void handle_pci_cfg_write(struct mdev_state *mdev_state, u16 offset,
char *buf, u32 count)
{
struct device *dev = mdev_dev(mdev_state->mdev);
int index = (offset - PCI_BASE_ADDRESS_0) / 0x04;
u32 cfg_addr;
switch (offset) {
case PCI_BASE_ADDRESS_0:
case PCI_BASE_ADDRESS_2:
cfg_addr = *(u32 *)buf;
if (cfg_addr == 0xffffffff) {
cfg_addr = (cfg_addr & mdev_state->bar_mask[index]);
} else {
cfg_addr &= PCI_BASE_ADDRESS_MEM_MASK;
if (cfg_addr)
dev_info(dev, "BAR #%d @ 0x%x\n",
index, cfg_addr);
}
cfg_addr |= (mdev_state->vconfig[offset] &
~PCI_BASE_ADDRESS_MEM_MASK);
STORE_LE32(&mdev_state->vconfig[offset], cfg_addr);
break;
}
}
static void handle_mmio_write(struct mdev_state *mdev_state, u16 offset,
char *buf, u32 count)
{
struct device *dev = mdev_dev(mdev_state->mdev);
int index;
u16 reg16;
switch (offset) {
case 0x400 ... 0x41f: /* vga ioports remapped */
goto unhandled;
case 0x500 ... 0x515: /* bochs dispi interface */
if (count != 2)
goto unhandled;
index = (offset - 0x500) / 2;
reg16 = *(u16 *)buf;
if (index < ARRAY_SIZE(mdev_state->vbe))
mdev_state->vbe[index] = reg16;
dev_dbg(dev, "%s: vbe write %d = %d (%s)\n",
__func__, index, reg16, vbe_name(index));
break;
case 0x600 ... 0x607: /* qemu extended regs */
goto unhandled;
default:
unhandled:
dev_dbg(dev, "%s: @0x%03x, count %d (unhandled)\n",
__func__, offset, count);
break;
}
}
static void handle_mmio_read(struct mdev_state *mdev_state, u16 offset,
char *buf, u32 count)
{
struct device *dev = mdev_dev(mdev_state->mdev);
struct vfio_region_gfx_edid *edid;
u16 reg16 = 0;
int index;
switch (offset) {
case 0x000 ... 0x3ff: /* edid block */
edid = &mdev_state->edid_regs;
if (edid->link_state != VFIO_DEVICE_GFX_LINK_STATE_UP ||
offset >= edid->edid_size) {
memset(buf, 0, count);
break;
}
memcpy(buf, mdev_state->edid_blob + offset, count);
break;
case 0x500 ... 0x515: /* bochs dispi interface */
if (count != 2)
goto unhandled;
index = (offset - 0x500) / 2;
if (index < ARRAY_SIZE(mdev_state->vbe))
reg16 = mdev_state->vbe[index];
dev_dbg(dev, "%s: vbe read %d = %d (%s)\n",
__func__, index, reg16, vbe_name(index));
*(u16 *)buf = reg16;
break;
default:
unhandled:
dev_dbg(dev, "%s: @0x%03x, count %d (unhandled)\n",
__func__, offset, count);
memset(buf, 0, count);
break;
}
}
static void handle_edid_regs(struct mdev_state *mdev_state, u16 offset,
char *buf, u32 count, bool is_write)
{
char *regs = (void *)&mdev_state->edid_regs;
if (offset + count > sizeof(mdev_state->edid_regs))
return;
if (count != 4)
return;
if (offset % 4)
return;
if (is_write) {
switch (offset) {
case offsetof(struct vfio_region_gfx_edid, link_state):
case offsetof(struct vfio_region_gfx_edid, edid_size):
memcpy(regs + offset, buf, count);
break;
default:
/* read-only regs */
break;
}
} else {
memcpy(buf, regs + offset, count);
}
}
static void handle_edid_blob(struct mdev_state *mdev_state, u16 offset,
char *buf, u32 count, bool is_write)
{
if (offset + count > mdev_state->edid_regs.edid_max_size)
return;
if (is_write)
memcpy(mdev_state->edid_blob + offset, buf, count);
else
memcpy(buf, mdev_state->edid_blob + offset, count);
}
static ssize_t mdev_access(struct mdev_state *mdev_state, char *buf,
size_t count, loff_t pos, bool is_write)
{
struct page *pg;
loff_t poff;
char *map;
int ret = 0;
mutex_lock(&mdev_state->ops_lock);
if (pos < MBOCHS_CONFIG_SPACE_SIZE) {
if (is_write)
handle_pci_cfg_write(mdev_state, pos, buf, count);
else
memcpy(buf, (mdev_state->vconfig + pos), count);
} else if (pos >= MBOCHS_MMIO_BAR_OFFSET &&
pos + count <= (MBOCHS_MMIO_BAR_OFFSET +
MBOCHS_MMIO_BAR_SIZE)) {
pos -= MBOCHS_MMIO_BAR_OFFSET;
if (is_write)
handle_mmio_write(mdev_state, pos, buf, count);
else
handle_mmio_read(mdev_state, pos, buf, count);
} else if (pos >= MBOCHS_EDID_OFFSET &&
pos + count <= (MBOCHS_EDID_OFFSET +
MBOCHS_EDID_SIZE)) {
pos -= MBOCHS_EDID_OFFSET;
if (pos < MBOCHS_EDID_BLOB_OFFSET) {
handle_edid_regs(mdev_state, pos, buf, count, is_write);
} else {
pos -= MBOCHS_EDID_BLOB_OFFSET;
handle_edid_blob(mdev_state, pos, buf, count, is_write);
}
} else if (pos >= MBOCHS_MEMORY_BAR_OFFSET &&
pos + count <=
MBOCHS_MEMORY_BAR_OFFSET + mdev_state->memsize) {
pos -= MBOCHS_MMIO_BAR_OFFSET;
poff = pos & ~PAGE_MASK;
pg = __mbochs_get_page(mdev_state, pos >> PAGE_SHIFT);
map = kmap(pg);
if (is_write)
memcpy(map + poff, buf, count);
else
memcpy(buf, map + poff, count);
kunmap(pg);
put_page(pg);
} else {
dev_dbg(mdev_state->vdev.dev, "%s: %s @0x%llx (unhandled)\n",
__func__, is_write ? "WR" : "RD", pos);
ret = -1;
goto accessfailed;
}
ret = count;
accessfailed:
mutex_unlock(&mdev_state->ops_lock);
return ret;
}
static int mbochs_reset(struct mdev_state *mdev_state)
{
u32 size64k = mdev_state->memsize / (64 * 1024);
int i;
for (i = 0; i < ARRAY_SIZE(mdev_state->vbe); i++)
mdev_state->vbe[i] = 0;
mdev_state->vbe[VBE_DISPI_INDEX_ID] = VBE_DISPI_ID5;
mdev_state->vbe[VBE_DISPI_INDEX_VIDEO_MEMORY_64K] = size64k;
return 0;
}
static int mbochs_probe(struct mdev_device *mdev)
{
int avail_mbytes = atomic_read(&mbochs_avail_mbytes);
const struct mbochs_type *type =
&mbochs_types[mdev_get_type_group_id(mdev)];
struct device *dev = mdev_dev(mdev);
struct mdev_state *mdev_state;
int ret = -ENOMEM;
do {
if (avail_mbytes < type->mbytes)
return -ENOSPC;
} while (!atomic_try_cmpxchg(&mbochs_avail_mbytes, &avail_mbytes,
avail_mbytes - type->mbytes));
mdev_state = kzalloc(sizeof(struct mdev_state), GFP_KERNEL);
if (mdev_state == NULL)
goto err_avail;
vfio_init_group_dev(&mdev_state->vdev, &mdev->dev, &mbochs_dev_ops);
mdev_state->vconfig = kzalloc(MBOCHS_CONFIG_SPACE_SIZE, GFP_KERNEL);
if (mdev_state->vconfig == NULL)
goto err_mem;
mdev_state->memsize = type->mbytes * 1024 * 1024;
mdev_state->pagecount = mdev_state->memsize >> PAGE_SHIFT;
mdev_state->pages = kcalloc(mdev_state->pagecount,
sizeof(struct page *),
GFP_KERNEL);
if (!mdev_state->pages)
goto err_mem;
dev_info(dev, "%s: %s, %d MB, %ld pages\n", __func__,
type->name, type->mbytes, mdev_state->pagecount);
mutex_init(&mdev_state->ops_lock);
mdev_state->mdev = mdev;
INIT_LIST_HEAD(&mdev_state->dmabufs);
mdev_state->next_id = 1;
mdev_state->type = type;
mdev_state->edid_regs.max_xres = type->max_x;
mdev_state->edid_regs.max_yres = type->max_y;
mdev_state->edid_regs.edid_offset = MBOCHS_EDID_BLOB_OFFSET;
mdev_state->edid_regs.edid_max_size = sizeof(mdev_state->edid_blob);
mbochs_create_config_space(mdev_state);
mbochs_reset(mdev_state);
ret = vfio_register_group_dev(&mdev_state->vdev);
if (ret)
goto err_mem;
dev_set_drvdata(&mdev->dev, mdev_state);
return 0;
err_mem:
kfree(mdev_state->pages);
kfree(mdev_state->vconfig);
kfree(mdev_state);
err_avail:
atomic_add(type->mbytes, &mbochs_avail_mbytes);
return ret;
}
static void mbochs_remove(struct mdev_device *mdev)
{
struct mdev_state *mdev_state = dev_get_drvdata(&mdev->dev);
vfio_unregister_group_dev(&mdev_state->vdev);
atomic_add(mdev_state->type->mbytes, &mbochs_avail_mbytes);
kfree(mdev_state->pages);
kfree(mdev_state->vconfig);
kfree(mdev_state);
}
static ssize_t mbochs_read(struct vfio_device *vdev, char __user *buf,
size_t count, loff_t *ppos)
{
struct mdev_state *mdev_state =
container_of(vdev, struct mdev_state, vdev);
unsigned int done = 0;
int ret;
while (count) {
size_t filled;
if (count >= 4 && !(*ppos % 4)) {
u32 val;
ret = mdev_access(mdev_state, (char *)&val, sizeof(val),
*ppos, false);
if (ret <= 0)
goto read_err;
if (copy_to_user(buf, &val, sizeof(val)))
goto read_err;
filled = 4;
} else if (count >= 2 && !(*ppos % 2)) {
u16 val;
ret = mdev_access(mdev_state, (char *)&val, sizeof(val),
*ppos, false);
if (ret <= 0)
goto read_err;
if (copy_to_user(buf, &val, sizeof(val)))
goto read_err;
filled = 2;
} else {
u8 val;
ret = mdev_access(mdev_state, (char *)&val, sizeof(val),
*ppos, false);
if (ret <= 0)
goto read_err;
if (copy_to_user(buf, &val, sizeof(val)))
goto read_err;
filled = 1;
}
count -= filled;
done += filled;
*ppos += filled;
buf += filled;
}
return done;
read_err:
return -EFAULT;
}
static ssize_t mbochs_write(struct vfio_device *vdev, const char __user *buf,
size_t count, loff_t *ppos)
{
struct mdev_state *mdev_state =
container_of(vdev, struct mdev_state, vdev);
unsigned int done = 0;
int ret;
while (count) {
size_t filled;
if (count >= 4 && !(*ppos % 4)) {
u32 val;
if (copy_from_user(&val, buf, sizeof(val)))
goto write_err;
ret = mdev_access(mdev_state, (char *)&val, sizeof(val),
*ppos, true);
if (ret <= 0)
goto write_err;
filled = 4;
} else if (count >= 2 && !(*ppos % 2)) {
u16 val;
if (copy_from_user(&val, buf, sizeof(val)))
goto write_err;
ret = mdev_access(mdev_state, (char *)&val, sizeof(val),
*ppos, true);
if (ret <= 0)
goto write_err;
filled = 2;
} else {
u8 val;
if (copy_from_user(&val, buf, sizeof(val)))
goto write_err;
ret = mdev_access(mdev_state, (char *)&val, sizeof(val),
*ppos, true);
if (ret <= 0)
goto write_err;
filled = 1;
}
count -= filled;
done += filled;
*ppos += filled;
buf += filled;
}
return done;
write_err:
return -EFAULT;
}
static struct page *__mbochs_get_page(struct mdev_state *mdev_state,
pgoff_t pgoff)
{
WARN_ON(!mutex_is_locked(&mdev_state->ops_lock));
if (!mdev_state->pages[pgoff]) {
mdev_state->pages[pgoff] =
alloc_pages(GFP_HIGHUSER | __GFP_ZERO, 0);
if (!mdev_state->pages[pgoff])
return NULL;
}
get_page(mdev_state->pages[pgoff]);
return mdev_state->pages[pgoff];
}
static struct page *mbochs_get_page(struct mdev_state *mdev_state,
pgoff_t pgoff)
{
struct page *page;
if (WARN_ON(pgoff >= mdev_state->pagecount))
return NULL;
mutex_lock(&mdev_state->ops_lock);
page = __mbochs_get_page(mdev_state, pgoff);
mutex_unlock(&mdev_state->ops_lock);
return page;
}
static void mbochs_put_pages(struct mdev_state *mdev_state)
{
struct device *dev = mdev_dev(mdev_state->mdev);
int i, count = 0;
WARN_ON(!mutex_is_locked(&mdev_state->ops_lock));
for (i = 0; i < mdev_state->pagecount; i++) {
if (!mdev_state->pages[i])
continue;
put_page(mdev_state->pages[i]);
mdev_state->pages[i] = NULL;
count++;
}
dev_dbg(dev, "%s: %d pages released\n", __func__, count);
}
static vm_fault_t mbochs_region_vm_fault(struct vm_fault *vmf)
{
struct vm_area_struct *vma = vmf->vma;
struct mdev_state *mdev_state = vma->vm_private_data;
pgoff_t page_offset = (vmf->address - vma->vm_start) >> PAGE_SHIFT;
if (page_offset >= mdev_state->pagecount)
return VM_FAULT_SIGBUS;
vmf->page = mbochs_get_page(mdev_state, page_offset);
if (!vmf->page)
return VM_FAULT_SIGBUS;
return 0;
}
static const struct vm_operations_struct mbochs_region_vm_ops = {
.fault = mbochs_region_vm_fault,
};
static int mbochs_mmap(struct vfio_device *vdev, struct vm_area_struct *vma)
{
struct mdev_state *mdev_state =
container_of(vdev, struct mdev_state, vdev);
if (vma->vm_pgoff != MBOCHS_MEMORY_BAR_OFFSET >> PAGE_SHIFT)
return -EINVAL;
if (vma->vm_end < vma->vm_start)
return -EINVAL;
if (vma->vm_end - vma->vm_start > mdev_state->memsize)
return -EINVAL;
if ((vma->vm_flags & VM_SHARED) == 0)
return -EINVAL;
vma->vm_ops = &mbochs_region_vm_ops;
vma->vm_private_data = mdev_state;
return 0;
}
static vm_fault_t mbochs_dmabuf_vm_fault(struct vm_fault *vmf)
{
struct vm_area_struct *vma = vmf->vma;
struct mbochs_dmabuf *dmabuf = vma->vm_private_data;
if (WARN_ON(vmf->pgoff >= dmabuf->pagecount))
return VM_FAULT_SIGBUS;
vmf->page = dmabuf->pages[vmf->pgoff];
get_page(vmf->page);
return 0;
}
static const struct vm_operations_struct mbochs_dmabuf_vm_ops = {
.fault = mbochs_dmabuf_vm_fault,
};
static int mbochs_mmap_dmabuf(struct dma_buf *buf, struct vm_area_struct *vma)
{
struct mbochs_dmabuf *dmabuf = buf->priv;
struct device *dev = mdev_dev(dmabuf->mdev_state->mdev);
dev_dbg(dev, "%s: %d\n", __func__, dmabuf->id);
if ((vma->vm_flags & VM_SHARED) == 0)
return -EINVAL;
vma->vm_ops = &mbochs_dmabuf_vm_ops;
vma->vm_private_data = dmabuf;
return 0;
}
static void mbochs_print_dmabuf(struct mbochs_dmabuf *dmabuf,
const char *prefix)
{
struct device *dev = mdev_dev(dmabuf->mdev_state->mdev);
u32 fourcc = dmabuf->mode.drm_format;
dev_dbg(dev, "%s/%d: %c%c%c%c, %dx%d, stride %d, off 0x%llx, size 0x%llx, pages %ld\n",
prefix, dmabuf->id,
fourcc ? ((fourcc >> 0) & 0xff) : '-',
fourcc ? ((fourcc >> 8) & 0xff) : '-',
fourcc ? ((fourcc >> 16) & 0xff) : '-',
fourcc ? ((fourcc >> 24) & 0xff) : '-',
dmabuf->mode.width, dmabuf->mode.height, dmabuf->mode.stride,
dmabuf->mode.offset, dmabuf->mode.size, dmabuf->pagecount);
}
static struct sg_table *mbochs_map_dmabuf(struct dma_buf_attachment *at,
enum dma_data_direction direction)
{
struct mbochs_dmabuf *dmabuf = at->dmabuf->priv;
struct device *dev = mdev_dev(dmabuf->mdev_state->mdev);
struct sg_table *sg;
dev_dbg(dev, "%s: %d\n", __func__, dmabuf->id);
sg = kzalloc(sizeof(*sg), GFP_KERNEL);
if (!sg)
goto err1;
if (sg_alloc_table_from_pages(sg, dmabuf->pages, dmabuf->pagecount,
0, dmabuf->mode.size, GFP_KERNEL) < 0)
goto err2;
if (dma_map_sgtable(at->dev, sg, direction, 0))
goto err3;
return sg;
err3:
sg_free_table(sg);
err2:
kfree(sg);
err1:
return ERR_PTR(-ENOMEM);
}
static void mbochs_unmap_dmabuf(struct dma_buf_attachment *at,
struct sg_table *sg,
enum dma_data_direction direction)
{
struct mbochs_dmabuf *dmabuf = at->dmabuf->priv;
struct device *dev = mdev_dev(dmabuf->mdev_state->mdev);
dev_dbg(dev, "%s: %d\n", __func__, dmabuf->id);
dma_unmap_sgtable(at->dev, sg, direction, 0);
sg_free_table(sg);
kfree(sg);
}
static void mbochs_release_dmabuf(struct dma_buf *buf)
{
struct mbochs_dmabuf *dmabuf = buf->priv;
struct mdev_state *mdev_state = dmabuf->mdev_state;
struct device *dev = mdev_dev(mdev_state->mdev);
pgoff_t pg;
dev_dbg(dev, "%s: %d\n", __func__, dmabuf->id);
for (pg = 0; pg < dmabuf->pagecount; pg++)
put_page(dmabuf->pages[pg]);
mutex_lock(&mdev_state->ops_lock);
dmabuf->buf = NULL;
if (dmabuf->unlinked)
kfree(dmabuf);
mutex_unlock(&mdev_state->ops_lock);
}
static struct dma_buf_ops mbochs_dmabuf_ops = {
.map_dma_buf = mbochs_map_dmabuf,
.unmap_dma_buf = mbochs_unmap_dmabuf,
.release = mbochs_release_dmabuf,
.mmap = mbochs_mmap_dmabuf,
};
static struct mbochs_dmabuf *mbochs_dmabuf_alloc(struct mdev_state *mdev_state,
struct mbochs_mode *mode)
{
struct mbochs_dmabuf *dmabuf;
pgoff_t page_offset, pg;
WARN_ON(!mutex_is_locked(&mdev_state->ops_lock));
dmabuf = kzalloc(sizeof(struct mbochs_dmabuf), GFP_KERNEL);
if (!dmabuf)
return NULL;
dmabuf->mode = *mode;
dmabuf->id = mdev_state->next_id++;
dmabuf->pagecount = DIV_ROUND_UP(mode->size, PAGE_SIZE);
dmabuf->pages = kcalloc(dmabuf->pagecount, sizeof(struct page *),
GFP_KERNEL);
if (!dmabuf->pages)
goto err_free_dmabuf;
page_offset = dmabuf->mode.offset >> PAGE_SHIFT;
for (pg = 0; pg < dmabuf->pagecount; pg++) {
dmabuf->pages[pg] = __mbochs_get_page(mdev_state,
page_offset + pg);
if (!dmabuf->pages[pg])
goto err_free_pages;
}
dmabuf->mdev_state = mdev_state;
list_add(&dmabuf->next, &mdev_state->dmabufs);
mbochs_print_dmabuf(dmabuf, __func__);
return dmabuf;
err_free_pages:
while (pg > 0)
put_page(dmabuf->pages[--pg]);
kfree(dmabuf->pages);
err_free_dmabuf:
kfree(dmabuf);
return NULL;
}
static struct mbochs_dmabuf *
mbochs_dmabuf_find_by_mode(struct mdev_state *mdev_state,
struct mbochs_mode *mode)
{
struct mbochs_dmabuf *dmabuf;
WARN_ON(!mutex_is_locked(&mdev_state->ops_lock));
list_for_each_entry(dmabuf, &mdev_state->dmabufs, next)
if (mbochs_modes_equal(&dmabuf->mode, mode))
return dmabuf;
return NULL;
}
static struct mbochs_dmabuf *
mbochs_dmabuf_find_by_id(struct mdev_state *mdev_state, u32 id)
{
struct mbochs_dmabuf *dmabuf;
WARN_ON(!mutex_is_locked(&mdev_state->ops_lock));
list_for_each_entry(dmabuf, &mdev_state->dmabufs, next)
if (dmabuf->id == id)
return dmabuf;
return NULL;
}
static int mbochs_dmabuf_export(struct mbochs_dmabuf *dmabuf)
{
struct mdev_state *mdev_state = dmabuf->mdev_state;
struct device *dev = mdev_state->vdev.dev;
DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
struct dma_buf *buf;
WARN_ON(!mutex_is_locked(&mdev_state->ops_lock));
if (!IS_ALIGNED(dmabuf->mode.offset, PAGE_SIZE)) {
dev_info_ratelimited(dev, "%s: framebuffer not page-aligned\n",
__func__);
return -EINVAL;
}
exp_info.ops = &mbochs_dmabuf_ops;
exp_info.size = dmabuf->mode.size;
exp_info.priv = dmabuf;
buf = dma_buf_export(&exp_info);
if (IS_ERR(buf)) {
dev_info_ratelimited(dev, "%s: dma_buf_export failed: %ld\n",
__func__, PTR_ERR(buf));
return PTR_ERR(buf);
}