1 /*
2 * SCLP event types
3 * Operations Command - Line Mode input
4 * Message - Line Mode output
5 *
6 * Copyright IBM, Corp. 2013
7 *
8 * Authors:
9 * Heinz Graalfs <graalfs@linux.vnet.ibm.com>
10 *
11 * This work is licensed under the terms of the GNU GPL, version 2 or (at your
12 * option) any later version. See the COPYING file in the top-level directory.
13 *
14 */
15
16 #include "qemu/osdep.h"
17 #include "qemu/thread.h"
18 #include "qemu/error-report.h"
19 #include "qemu/module.h"
20 #include "chardev/char-fe.h"
21
22 #include "hw/s390x/sclp.h"
23 #include "migration/vmstate.h"
24 #include "hw/s390x/event-facility.h"
25 #include "hw/qdev-properties.h"
26 #include "hw/qdev-properties-system.h"
27 #include "hw/s390x/ebcdic.h"
28 #include "qom/object.h"
29
30 #define SIZE_BUFFER 4096
31 #define NEWLINE "\n"
32
33 typedef struct OprtnsCommand {
34 EventBufferHeader header;
35 MDMSU message_unit;
36 char data[];
37 } QEMU_PACKED OprtnsCommand;
38
39 /* max size for line-mode data in 4K SCCB page */
40 #define SIZE_CONSOLE_BUFFER (SCCB_DATA_LEN - sizeof(OprtnsCommand))
41
42 struct SCLPConsoleLM {
43 SCLPEvent event;
44 CharBackend chr;
45 bool echo; /* immediate echo of input if true */
46 uint32_t write_errors; /* errors writing to char layer */
47 uint32_t length; /* length of byte stream in buffer */
48 uint8_t buf[SIZE_CONSOLE_BUFFER];
49 };
50 typedef struct SCLPConsoleLM SCLPConsoleLM;
51
52 #define TYPE_SCLPLM_CONSOLE "sclplmconsole"
DECLARE_INSTANCE_CHECKER(SCLPConsoleLM,SCLPLM_CONSOLE,TYPE_SCLPLM_CONSOLE)53 DECLARE_INSTANCE_CHECKER(SCLPConsoleLM, SCLPLM_CONSOLE,
54 TYPE_SCLPLM_CONSOLE)
55
56 /*
57 * Character layer call-back functions
58 *
59 * Allow 1 character at a time
60 *
61 * Accumulate bytes from character layer in console buffer,
62 * event_pending is set when a newline character is encountered
63 *
64 * The maximum command line length is limited by the maximum
65 * space available in an SCCB. Line mode console input is sent
66 * truncated to the guest in case it doesn't fit into the SCCB.
67 */
68
69 static int chr_can_read(void *opaque)
70 {
71 SCLPConsoleLM *scon = opaque;
72
73 if (scon->event.event_pending) {
74 return 0;
75 }
76 return 1;
77 }
78
chr_read(void * opaque,const uint8_t * buf,int size)79 static void chr_read(void *opaque, const uint8_t *buf, int size)
80 {
81 SCLPConsoleLM *scon = opaque;
82
83 assert(size == 1);
84
85 if (*buf == '\r' || *buf == '\n') {
86 scon->event.event_pending = true;
87 sclp_service_interrupt(0);
88 return;
89 }
90 if (scon->length == SIZE_CONSOLE_BUFFER) {
91 /* Eat the character, but still process CR and LF. */
92 return;
93 }
94 scon->buf[scon->length] = *buf;
95 scon->length += 1;
96 if (scon->echo) {
97 /* XXX this blocks entire thread. Rewrite to use
98 * qemu_chr_fe_write and background I/O callbacks */
99 qemu_chr_fe_write_all(&scon->chr, buf, size);
100 }
101 }
102
103 /* functions to be called by event facility */
104
can_handle_event(uint8_t type)105 static bool can_handle_event(uint8_t type)
106 {
107 return type == SCLP_EVENT_MESSAGE || type == SCLP_EVENT_PMSGCMD;
108 }
109
send_mask(void)110 static sccb_mask_t send_mask(void)
111 {
112 return SCLP_EVENT_MASK_OP_CMD | SCLP_EVENT_MASK_PMSGCMD;
113 }
114
receive_mask(void)115 static sccb_mask_t receive_mask(void)
116 {
117 return SCLP_EVENT_MASK_MSG | SCLP_EVENT_MASK_PMSGCMD;
118 }
119
120 /*
121 * Triggered by SCLP's read_event_data
122 * - convert ASCII byte stream to EBCDIC and
123 * - copy converted data into provided (SCLP) buffer
124 */
get_console_data(SCLPEvent * event,uint8_t * buf,size_t * size,int avail)125 static int get_console_data(SCLPEvent *event, uint8_t *buf, size_t *size,
126 int avail)
127 {
128 int len;
129
130 SCLPConsoleLM *cons = SCLPLM_CONSOLE(event);
131
132 len = cons->length;
133 /* data need to fit into provided SCLP buffer */
134 if (len > avail) {
135 return 1;
136 }
137
138 ebcdic_put(buf, (char *)&cons->buf, len);
139 *size = len;
140 cons->length = 0;
141 /* data provided and no more data pending */
142 event->event_pending = false;
143 qemu_notify_event();
144 return 0;
145 }
146
read_event_data(SCLPEvent * event,EventBufferHeader * evt_buf_hdr,int * slen)147 static int read_event_data(SCLPEvent *event, EventBufferHeader *evt_buf_hdr,
148 int *slen)
149 {
150 int avail, rc;
151 size_t src_len;
152 uint8_t *to;
153 OprtnsCommand *oc = (OprtnsCommand *) evt_buf_hdr;
154
155 if (!event->event_pending) {
156 /* no data pending */
157 return 0;
158 }
159
160 to = (uint8_t *)&oc->data;
161 avail = *slen - sizeof(OprtnsCommand);
162 rc = get_console_data(event, to, &src_len, avail);
163 if (rc) {
164 /* data didn't fit, try next SCCB */
165 return 1;
166 }
167
168 oc->message_unit.mdmsu.gds_id = GDS_ID_MDSMU;
169 oc->message_unit.mdmsu.length = cpu_to_be16(sizeof(struct MDMSU));
170
171 oc->message_unit.cpmsu.gds_id = GDS_ID_CPMSU;
172 oc->message_unit.cpmsu.length =
173 cpu_to_be16(sizeof(struct MDMSU) - sizeof(GdsVector));
174
175 oc->message_unit.text_command.gds_id = GDS_ID_TEXTCMD;
176 oc->message_unit.text_command.length =
177 cpu_to_be16(sizeof(struct MDMSU) - (2 * sizeof(GdsVector)));
178
179 oc->message_unit.self_def_text_message.key = GDS_KEY_SELFDEFTEXTMSG;
180 oc->message_unit.self_def_text_message.length =
181 cpu_to_be16(sizeof(struct MDMSU) - (3 * sizeof(GdsVector)));
182
183 oc->message_unit.text_message.key = GDS_KEY_TEXTMSG;
184 oc->message_unit.text_message.length =
185 cpu_to_be16(sizeof(GdsSubvector) + src_len);
186
187 oc->header.length = cpu_to_be16(sizeof(OprtnsCommand) + src_len);
188 oc->header.type = SCLP_EVENT_OPRTNS_COMMAND;
189 *slen = avail - src_len;
190
191 return 1;
192 }
193
194 /*
195 * Triggered by SCLP's write_event_data
196 * - write console data to character layer
197 * returns < 0 if an error occurred
198 */
write_console_data(SCLPEvent * event,const uint8_t * buf,int len)199 static int write_console_data(SCLPEvent *event, const uint8_t *buf, int len)
200 {
201 SCLPConsoleLM *scon = SCLPLM_CONSOLE(event);
202
203 if (!qemu_chr_fe_backend_connected(&scon->chr)) {
204 /* If there's no backend, we can just say we consumed all data. */
205 return len;
206 }
207
208 /* XXX this blocks entire thread. Rewrite to use
209 * qemu_chr_fe_write and background I/O callbacks */
210 return qemu_chr_fe_write_all(&scon->chr, buf, len);
211 }
212
process_mdb(SCLPEvent * event,MDBO * mdbo)213 static int process_mdb(SCLPEvent *event, MDBO *mdbo)
214 {
215 int rc;
216 int len;
217 uint8_t buffer[SIZE_BUFFER];
218
219 len = be16_to_cpu(mdbo->length);
220 len -= sizeof(mdbo->length) + sizeof(mdbo->type)
221 + sizeof(mdbo->mto.line_type_flags)
222 + sizeof(mdbo->mto.alarm_control)
223 + sizeof(mdbo->mto._reserved);
224
225 assert(len <= SIZE_BUFFER);
226
227 /* convert EBCDIC SCLP contents to ASCII console message */
228 ascii_put(buffer, mdbo->mto.message, len);
229 rc = write_console_data(event, (uint8_t *)NEWLINE, 1);
230 if (rc < 0) {
231 return rc;
232 }
233 return write_console_data(event, buffer, len);
234 }
235
write_event_data(SCLPEvent * event,EventBufferHeader * ebh)236 static int write_event_data(SCLPEvent *event, EventBufferHeader *ebh)
237 {
238 int len;
239 int written;
240 int errors = 0;
241 MDBO *mdbo;
242 SclpMsg *data = (SclpMsg *) ebh;
243 SCLPConsoleLM *scon = SCLPLM_CONSOLE(event);
244
245 len = be16_to_cpu(data->mdb.header.length);
246 if (len < sizeof(data->mdb.header)) {
247 return SCLP_RC_INCONSISTENT_LENGTHS;
248 }
249 len -= sizeof(data->mdb.header);
250
251 /* first check message buffers */
252 mdbo = data->mdb.mdbo;
253 while (len > 0) {
254 if (be16_to_cpu(mdbo->length) > len
255 || be16_to_cpu(mdbo->length) == 0) {
256 return SCLP_RC_INCONSISTENT_LENGTHS;
257 }
258 len -= be16_to_cpu(mdbo->length);
259 mdbo = (void *) mdbo + be16_to_cpu(mdbo->length);
260 }
261
262 /* then execute */
263 len = be16_to_cpu(data->mdb.header.length) - sizeof(data->mdb.header);
264 mdbo = data->mdb.mdbo;
265 while (len > 0) {
266 switch (be16_to_cpu(mdbo->type)) {
267 case MESSAGE_TEXT:
268 /* message text object */
269 written = process_mdb(event, mdbo);
270 if (written < 0) {
271 /* character layer error */
272 errors++;
273 }
274 break;
275 default: /* ignore */
276 break;
277 }
278 len -= be16_to_cpu(mdbo->length);
279 mdbo = (void *) mdbo + be16_to_cpu(mdbo->length);
280 }
281 if (errors) {
282 scon->write_errors += errors;
283 }
284 data->header.flags = SCLP_EVENT_BUFFER_ACCEPTED;
285
286 return SCLP_RC_NORMAL_COMPLETION;
287 }
288
289 /* functions for live migration */
290
291 static const VMStateDescription vmstate_sclplmconsole = {
292 .name = "sclplmconsole",
293 .version_id = 0,
294 .minimum_version_id = 0,
295 .fields = (const VMStateField[]) {
296 VMSTATE_BOOL(event.event_pending, SCLPConsoleLM),
297 VMSTATE_UINT32(write_errors, SCLPConsoleLM),
298 VMSTATE_UINT32(length, SCLPConsoleLM),
299 VMSTATE_UINT8_ARRAY(buf, SCLPConsoleLM, SIZE_CONSOLE_BUFFER),
300 VMSTATE_END_OF_LIST()
301 }
302 };
303
304 /* qemu object creation and initialization functions */
305
306 /* tell character layer our call-back functions */
307
console_init(SCLPEvent * event)308 static int console_init(SCLPEvent *event)
309 {
310 static bool console_available;
311
312 SCLPConsoleLM *scon = SCLPLM_CONSOLE(event);
313
314 if (console_available) {
315 error_report("Multiple line-mode operator consoles are not supported");
316 return -1;
317 }
318 console_available = true;
319
320 qemu_chr_fe_set_handlers(&scon->chr, chr_can_read,
321 chr_read, NULL, NULL, scon, NULL, true);
322
323 return 0;
324 }
325
console_reset(DeviceState * dev)326 static void console_reset(DeviceState *dev)
327 {
328 SCLPEvent *event = SCLP_EVENT(dev);
329 SCLPConsoleLM *scon = SCLPLM_CONSOLE(event);
330
331 event->event_pending = false;
332 scon->length = 0;
333 scon->write_errors = 0;
334 }
335
336 static Property console_properties[] = {
337 DEFINE_PROP_CHR("chardev", SCLPConsoleLM, chr),
338 DEFINE_PROP_UINT32("write_errors", SCLPConsoleLM, write_errors, 0),
339 DEFINE_PROP_BOOL("echo", SCLPConsoleLM, echo, true),
340 DEFINE_PROP_END_OF_LIST(),
341 };
342
console_class_init(ObjectClass * klass,void * data)343 static void console_class_init(ObjectClass *klass, void *data)
344 {
345 DeviceClass *dc = DEVICE_CLASS(klass);
346 SCLPEventClass *ec = SCLP_EVENT_CLASS(klass);
347
348 device_class_set_props(dc, console_properties);
349 device_class_set_legacy_reset(dc, console_reset);
350 dc->vmsd = &vmstate_sclplmconsole;
351 ec->init = console_init;
352 ec->get_send_mask = send_mask;
353 ec->get_receive_mask = receive_mask;
354 ec->can_handle_event = can_handle_event;
355 ec->read_event_data = read_event_data;
356 ec->write_event_data = write_event_data;
357 set_bit(DEVICE_CATEGORY_INPUT, dc->categories);
358 }
359
360 static const TypeInfo sclp_console_info = {
361 .name = TYPE_SCLPLM_CONSOLE,
362 .parent = TYPE_SCLP_EVENT,
363 .instance_size = sizeof(SCLPConsoleLM),
364 .class_init = console_class_init,
365 .class_size = sizeof(SCLPEventClass),
366 };
367
register_types(void)368 static void register_types(void)
369 {
370 type_register_static(&sclp_console_info);
371 }
372
373 type_init(register_types)
374