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
|
/*
* Copyright (C) 2010 - 2015 UNISYS CORPORATION
* All rights reserved.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
* NON INFRINGEMENT. See the GNU General Public License for more
* details.
*/
/*
* This provides s-Par channel communication primitives, which are
* independent of the mechanism used to access the channel data.
*/
#include <linux/uuid.h>
#include <linux/io.h>
#include <linux/slab.h>
#include "visorbus.h"
#include "visorbus_private.h"
#include "controlvmchannel.h"
#define VISOR_DRV_NAME "visorchannel"
#define VISOR_CONSOLEVIDEO_CHANNEL_GUID \
GUID_INIT(0x3cd6e705, 0xd6a2, 0x4aa5, \
0xad, 0x5c, 0x7b, 0x8, 0x88, 0x9d, 0xff, 0xe2)
static const guid_t visor_video_guid = VISOR_CONSOLEVIDEO_CHANNEL_GUID;
struct visorchannel {
u64 physaddr;
ulong nbytes;
void *mapped;
bool requested;
struct channel_header chan_hdr;
guid_t guid;
/*
* channel creator knows if more than one thread will be inserting or
* removing
*/
bool needs_lock;
/* protect head writes in chan_hdr */
spinlock_t insert_lock;
/* protect tail writes in chan_hdr */
spinlock_t remove_lock;
guid_t type;
guid_t inst;
};
void visorchannel_destroy(struct visorchannel *channel)
{
if (!channel)
return;
if (channel->mapped) {
memunmap(channel->mapped);
if (channel->requested)
release_mem_region(channel->physaddr, channel->nbytes);
}
kfree(channel);
}
u64 visorchannel_get_physaddr(struct visorchannel *channel)
{
return channel->physaddr;
}
ulong visorchannel_get_nbytes(struct visorchannel *channel)
{
return channel->nbytes;
}
char *visorchannel_guid_id(const guid_t *guid, char *s)
{
sprintf(s, "%pUL", guid);
return s;
}
char *visorchannel_id(struct visorchannel *channel, char *s)
{
return visorchannel_guid_id(&channel->guid, s);
}
char *visorchannel_zoneid(struct visorchannel *channel, char *s)
{
return visorchannel_guid_id(&channel->chan_hdr.zone_guid, s);
}
u64 visorchannel_get_clientpartition(struct visorchannel *channel)
{
return channel->chan_hdr.partition_handle;
}
int visorchannel_set_clientpartition(struct visorchannel *channel,
u64 partition_handle)
{
channel->chan_hdr.partition_handle = partition_handle;
return 0;
}
/**
* visorchannel_get_guid() - queries the GUID of the designated channel
* @channel: the channel to query
*
* Return: the GUID of the provided channel
*/
const guid_t *visorchannel_get_guid(struct visorchannel *channel)
{
return &channel->guid;
}
EXPORT_SYMBOL_GPL(visorchannel_get_guid);
int visorchannel_read(struct visorchannel *channel, ulong offset, void *dest,
ulong nbytes)
{
if (offset + nbytes > channel->nbytes)
return -EIO;
memcpy(dest, channel->mapped + offset, nbytes);
return 0;
}
int visorchannel_write(struct visorchannel *channel, ulong offset, void *dest,
ulong nbytes)
{
size_t chdr_size = sizeof(struct channel_header);
size_t copy_size;
if (offset + nbytes > channel->nbytes)
return -EIO;
if (offset < chdr_size) {
copy_size = min(chdr_size - offset, nbytes);
memcpy(((char *)(&channel->chan_hdr)) + offset,
dest, copy_size);
}
memcpy(channel->mapped + offset, dest, nbytes);
return 0;
}
void *visorchannel_get_header(struct visorchannel *channel)
{
return &channel->chan_hdr;
}
/*
* Return offset of a specific SIGNAL_QUEUE_HEADER from the beginning of a
* channel header
*/
static int sig_queue_offset(struct channel_header *chan_hdr, int q)
{
return ((chan_hdr)->ch_space_offset +
((q) * sizeof(struct signal_queue_header)));
}
/*
* Return offset of a specific queue entry (data) from the beginning of a
* channel header
*/
static int sig_data_offset(struct channel_header *chan_hdr, int q,
struct signal_queue_header *sig_hdr, int slot)
{
return (sig_queue_offset(chan_hdr, q) + sig_hdr->sig_base_offset +
(slot * sig_hdr->signal_size));
}
/*
* Write the contents of a specific field within a SIGNAL_QUEUE_HEADER back into
* host memory
*/
#define SIG_WRITE_FIELD(channel, queue, sig_hdr, FIELD) \
visorchannel_write(channel, \
sig_queue_offset(&channel->chan_hdr, queue) + \
offsetof(struct signal_queue_header, FIELD), \
&((sig_hdr)->FIELD), \
sizeof((sig_hdr)->FIELD))
static int sig_read_header(struct visorchannel *channel, u32 queue,
struct signal_queue_header *sig_hdr)
{
if (channel->chan_hdr.ch_space_offset < sizeof(struct channel_header))
return -EINVAL;
/* Read the appropriate SIGNAL_QUEUE_HEADER into local memory. */
return visorchannel_read(channel,
sig_queue_offset(&channel->chan_hdr, queue),
sig_hdr, sizeof(struct signal_queue_header));
}
static int sig_read_data(struct visorchannel *channel, u32 queue,
struct signal_queue_header *sig_hdr, u32 slot,
void *data)
{
int signal_data_offset = sig_data_offset(&channel->chan_hdr, queue,
sig_hdr, slot);
return visorchannel_read(channel, signal_data_offset,
data, sig_hdr->signal_size);
}
static int sig_write_data(struct visorchannel *channel, u32 queue,
struct signal_queue_header *sig_hdr, u32 slot,
void *data)
{
int signal_data_offset = sig_data_offset(&channel->chan_hdr, queue,
sig_hdr, slot);
return visorchannel_write(channel, signal_data_offset,
data, sig_hdr->signal_size);
}
static int signalremove_inner(struct visorchannel *channel, u32 queue,
void *msg)
{
struct signal_queue_header sig_hdr;
int error;
error = sig_read_header(channel, queue, &sig_hdr);
if (error)
return error;
/* No signals to remove; have caller try again. */
if (sig_hdr.head == sig_hdr.tail)
return -EAGAIN;
sig_hdr.tail = (sig_hdr.tail + 1) % sig_hdr.max_slots;
error = sig_read_data(channel, queue, &sig_hdr, sig_hdr.tail, msg);
if (error)
return error;
sig_hdr.num_received++;
/*
* For each data field in SIGNAL_QUEUE_HEADER that was modified, update
* host memory. Required for channel sync.
*/
mb();
error = SIG_WRITE_FIELD(channel, queue, &sig_hdr, tail);
if (error)
return error;
error = SIG_WRITE_FIELD(channel, queue, &sig_hdr, num_received);
if (error)
return error;
return 0;
}
/**
* visorchannel_signalremove() - removes a message from the designated
* channel/queue
* @channel: the channel the message will be removed from
* @queue: the queue the message will be removed from
* @msg: the message to remove
*
* Return: integer error code indicating the status of the removal
*/
int visorchannel_signalremove(struct visorchannel *channel, u32 queue,
void *msg)
{
int rc;
unsigned long flags;
if (channel->needs_lock) {
spin_lock_irqsave(&channel->remove_lock, flags);
rc = signalremove_inner(channel, queue, msg);
spin_unlock_irqrestore(&channel->remove_lock, flags);
} else {
rc = signalremove_inner(channel, queue, msg);
}
return rc;
}
EXPORT_SYMBOL_GPL(visorchannel_signalremove);
static bool queue_empty(struct visorchannel *channel, u32 queue)
{
struct signal_queue_header sig_hdr;
if (sig_read_header(channel, queue, &sig_hdr))
return true;
return (sig_hdr.head == sig_hdr.tail);
}
/**
* visorchannel_signalempty() - checks if the designated channel/queue contains
* any messages
* @channel: the channel to query
* @queue: the queue in the channel to query
*
* Return: boolean indicating whether any messages in the designated
* channel/queue are present
*/
bool
|