xref: /linux/drivers/s390/char/con3270.c (revision e58e871becec2d3b04ed91c0c16fe8deac9c9dfa)
1 /*
2  * IBM/3270 Driver - console view.
3  *
4  * Author(s):
5  *   Original 3270 Code for 2.4 written by Richard Hitt (UTS Global)
6  *   Rewritten for 2.5 by Martin Schwidefsky <schwidefsky@de.ibm.com>
7  *     Copyright IBM Corp. 2003, 2009
8  */
9 
10 #include <linux/module.h>
11 #include <linux/console.h>
12 #include <linux/init.h>
13 #include <linux/interrupt.h>
14 #include <linux/list.h>
15 #include <linux/types.h>
16 #include <linux/slab.h>
17 #include <linux/err.h>
18 #include <linux/reboot.h>
19 
20 #include <asm/ccwdev.h>
21 #include <asm/cio.h>
22 #include <asm/cpcmd.h>
23 #include <asm/ebcdic.h>
24 
25 #include "raw3270.h"
26 #include "tty3270.h"
27 #include "ctrlchar.h"
28 
29 #define CON3270_OUTPUT_BUFFER_SIZE 1024
30 #define CON3270_STRING_PAGES 4
31 
32 static struct raw3270_fn con3270_fn;
33 
34 static bool auto_update = true;
35 module_param(auto_update, bool, 0);
36 
37 /*
38  * Main 3270 console view data structure.
39  */
40 struct con3270 {
41 	struct raw3270_view view;
42 	struct list_head freemem;	/* list of free memory for strings. */
43 
44 	/* Output stuff. */
45 	struct list_head lines;		/* list of lines. */
46 	struct list_head update;	/* list of lines to update. */
47 	int line_nr;			/* line number for next update. */
48 	int nr_lines;			/* # lines in list. */
49 	int nr_up;			/* # lines up in history. */
50 	unsigned long update_flags;	/* Update indication bits. */
51 	struct string *cline;		/* current output line. */
52 	struct string *status;		/* last line of display. */
53 	struct raw3270_request *write;	/* single write request. */
54 	struct timer_list timer;
55 
56 	/* Input stuff. */
57 	struct string *input;		/* input string for read request. */
58 	struct raw3270_request *read;	/* single read request. */
59 	struct raw3270_request *kreset;	/* single keyboard reset request. */
60 	struct tasklet_struct readlet;	/* tasklet to issue read request. */
61 };
62 
63 static struct con3270 *condev;
64 
65 /* con3270->update_flags. See con3270_update for details. */
66 #define CON_UPDATE_ERASE	1	/* Use EWRITEA instead of WRITE. */
67 #define CON_UPDATE_LIST		2	/* Update lines in tty3270->update. */
68 #define CON_UPDATE_STATUS	4	/* Update status line. */
69 #define CON_UPDATE_ALL		8	/* Recreate screen. */
70 
71 static void con3270_update(struct con3270 *);
72 
73 /*
74  * Setup timeout for a device. On timeout trigger an update.
75  */
76 static void con3270_set_timer(struct con3270 *cp, int expires)
77 {
78 	if (expires == 0)
79 		del_timer(&cp->timer);
80 	else
81 		mod_timer(&cp->timer, jiffies + expires);
82 }
83 
84 /*
85  * The status line is the last line of the screen. It shows the string
86  * "console view" in the lower left corner and "Running"/"More..."/"Holding"
87  * in the lower right corner of the screen.
88  */
89 static void
90 con3270_update_status(struct con3270 *cp)
91 {
92 	char *str;
93 
94 	str = (cp->nr_up != 0) ? "History" : "Running";
95 	memcpy(cp->status->string + 24, str, 7);
96 	codepage_convert(cp->view.ascebc, cp->status->string + 24, 7);
97 	cp->update_flags |= CON_UPDATE_STATUS;
98 }
99 
100 static void
101 con3270_create_status(struct con3270 *cp)
102 {
103 	static const unsigned char blueprint[] =
104 		{ TO_SBA, 0, 0, TO_SF,TF_LOG,TO_SA,TAT_COLOR, TAC_GREEN,
105 		  'c','o','n','s','o','l','e',' ','v','i','e','w',
106 		  TO_RA,0,0,0,'R','u','n','n','i','n','g',TO_SF,TF_LOG };
107 
108 	cp->status = alloc_string(&cp->freemem, sizeof(blueprint));
109 	/* Copy blueprint to status line */
110 	memcpy(cp->status->string, blueprint, sizeof(blueprint));
111 	/* Set TO_RA addresses. */
112 	raw3270_buffer_address(cp->view.dev, cp->status->string + 1,
113 			       cp->view.cols * (cp->view.rows - 1));
114 	raw3270_buffer_address(cp->view.dev, cp->status->string + 21,
115 			       cp->view.cols * cp->view.rows - 8);
116 	/* Convert strings to ebcdic. */
117 	codepage_convert(cp->view.ascebc, cp->status->string + 8, 12);
118 	codepage_convert(cp->view.ascebc, cp->status->string + 24, 7);
119 }
120 
121 /*
122  * Set output offsets to 3270 datastream fragment of a console string.
123  */
124 static void
125 con3270_update_string(struct con3270 *cp, struct string *s, int nr)
126 {
127 	if (s->len < 4) {
128 		/* This indicates a bug, but printing a warning would
129 		 * cause a deadlock. */
130 		return;
131 	}
132 	if (s->string[s->len - 4] != TO_RA)
133 		return;
134 	raw3270_buffer_address(cp->view.dev, s->string + s->len - 3,
135 			       cp->view.cols * (nr + 1));
136 }
137 
138 /*
139  * Rebuild update list to print all lines.
140  */
141 static void
142 con3270_rebuild_update(struct con3270 *cp)
143 {
144 	struct string *s, *n;
145 	int nr;
146 
147 	/*
148 	 * Throw away update list and create a new one,
149 	 * containing all lines that will fit on the screen.
150 	 */
151 	list_for_each_entry_safe(s, n, &cp->update, update)
152 		list_del_init(&s->update);
153 	nr = cp->view.rows - 2 + cp->nr_up;
154 	list_for_each_entry_reverse(s, &cp->lines, list) {
155 		if (nr < cp->view.rows - 1)
156 			list_add(&s->update, &cp->update);
157 		if (--nr < 0)
158 			break;
159 	}
160 	cp->line_nr = 0;
161 	cp->update_flags |= CON_UPDATE_LIST;
162 }
163 
164 /*
165  * Alloc string for size bytes. Free strings from history if necessary.
166  */
167 static struct string *
168 con3270_alloc_string(struct con3270 *cp, size_t size)
169 {
170 	struct string *s, *n;
171 
172 	s = alloc_string(&cp->freemem, size);
173 	if (s)
174 		return s;
175 	list_for_each_entry_safe(s, n, &cp->lines, list) {
176 		list_del(&s->list);
177 		if (!list_empty(&s->update))
178 			list_del(&s->update);
179 		cp->nr_lines--;
180 		if (free_string(&cp->freemem, s) >= size)
181 			break;
182 	}
183 	s = alloc_string(&cp->freemem, size);
184 	BUG_ON(!s);
185 	if (cp->nr_up != 0 && cp->nr_up + cp->view.rows > cp->nr_lines) {
186 		cp->nr_up = cp->nr_lines - cp->view.rows + 1;
187 		con3270_rebuild_update(cp);
188 		con3270_update_status(cp);
189 	}
190 	return s;
191 }
192 
193 /*
194  * Write completion callback.
195  */
196 static void
197 con3270_write_callback(struct raw3270_request *rq, void *data)
198 {
199 	raw3270_request_reset(rq);
200 	xchg(&((struct con3270 *) rq->view)->write, rq);
201 }
202 
203 /*
204  * Update console display.
205  */
206 static void
207 con3270_update(struct con3270 *cp)
208 {
209 	struct raw3270_request *wrq;
210 	char wcc, prolog[6];
211 	unsigned long flags;
212 	unsigned long updated;
213 	struct string *s, *n;
214 	int rc;
215 
216 	if (!auto_update && !raw3270_view_active(&cp->view))
217 		return;
218 	if (cp->view.dev)
219 		raw3270_activate_view(&cp->view);
220 
221 	wrq = xchg(&cp->write, 0);
222 	if (!wrq) {
223 		con3270_set_timer(cp, 1);
224 		return;
225 	}
226 
227 	spin_lock_irqsave(&cp->view.lock, flags);
228 	updated = 0;
229 	if (cp->update_flags & CON_UPDATE_ALL) {
230 		con3270_rebuild_update(cp);
231 		con3270_update_status(cp);
232 		cp->update_flags = CON_UPDATE_ERASE | CON_UPDATE_LIST |
233 			CON_UPDATE_STATUS;
234 	}
235 	if (cp->update_flags & CON_UPDATE_ERASE) {
236 		/* Use erase write alternate to initialize display. */
237 		raw3270_request_set_cmd(wrq, TC_EWRITEA);
238 		updated |= CON_UPDATE_ERASE;
239 	} else
240 		raw3270_request_set_cmd(wrq, TC_WRITE);
241 
242 	wcc = TW_NONE;
243 	raw3270_request_add_data(wrq, &wcc, 1);
244 
245 	/*
246 	 * Update status line.
247 	 */
248 	if (cp->update_flags & CON_UPDATE_STATUS)
249 		if (raw3270_request_add_data(wrq, cp->status->string,
250 					     cp->status->len) == 0)
251 			updated |= CON_UPDATE_STATUS;
252 
253 	if (cp->update_flags & CON_UPDATE_LIST) {
254 		prolog[0] = TO_SBA;
255 		prolog[3] = TO_SA;
256 		prolog[4] = TAT_COLOR;
257 		prolog[5] = TAC_TURQ;
258 		raw3270_buffer_address(cp->view.dev, prolog + 1,
259 				       cp->view.cols * cp->line_nr);
260 		raw3270_request_add_data(wrq, prolog, 6);
261 		/* Write strings in the update list to the screen. */
262 		list_for_each_entry_safe(s, n, &cp->update, update) {
263 			if (s != cp->cline)
264 				con3270_update_string(cp, s, cp->line_nr);
265 			if (raw3270_request_add_data(wrq, s->string,
266 						     s->len) != 0)
267 				break;
268 			list_del_init(&s->update);
269 			if (s != cp->cline)
270 				cp->line_nr++;
271 		}
272 		if (list_empty(&cp->update))
273 			updated |= CON_UPDATE_LIST;
274 	}
275 	wrq->callback = con3270_write_callback;
276 	rc = raw3270_start(&cp->view, wrq);
277 	if (rc == 0) {
278 		cp->update_flags &= ~updated;
279 		if (cp->update_flags)
280 			con3270_set_timer(cp, 1);
281 	} else {
282 		raw3270_request_reset(wrq);
283 		xchg(&cp->write, wrq);
284 	}
285 	spin_unlock_irqrestore(&cp->view.lock, flags);
286 }
287 
288 /*
289  * Read tasklet.
290  */
291 static void
292 con3270_read_tasklet(struct raw3270_request *rrq)
293 {
294 	static char kreset_data = TW_KR;
295 	struct con3270 *cp;
296 	unsigned long flags;
297 	int nr_up, deactivate;
298 
299 	cp = (struct con3270 *) rrq->view;
300 	spin_lock_irqsave(&cp->view.lock, flags);
301 	nr_up = cp->nr_up;
302 	deactivate = 0;
303 	/* Check aid byte. */
304 	switch (cp->input->string[0]) {
305 	case 0x7d:	/* enter: jump to bottom. */
306 		nr_up = 0;
307 		break;
308 	case 0xf3:	/* PF3: deactivate the console view. */
309 		deactivate = 1;
310 		break;
311 	case 0x6d:	/* clear: start from scratch. */
312 		cp->update_flags = CON_UPDATE_ALL;
313 		con3270_set_timer(cp, 1);
314 		break;
315 	case 0xf7:	/* PF7: do a page up in the console log. */
316 		nr_up += cp->view.rows - 2;
317 		if (nr_up + cp->view.rows - 1 > cp->nr_lines) {
318 			nr_up = cp->nr_lines - cp->view.rows + 1;
319 			if (nr_up < 0)
320 				nr_up = 0;
321 		}
322 		break;
323 	case 0xf8:	/* PF8: do a page down in the console log. */
324 		nr_up -= cp->view.rows - 2;
325 		if (nr_up < 0)
326 			nr_up = 0;
327 		break;
328 	}
329 	if (nr_up != cp->nr_up) {
330 		cp->nr_up = nr_up;
331 		con3270_rebuild_update(cp);
332 		con3270_update_status(cp);
333 		con3270_set_timer(cp, 1);
334 	}
335 	spin_unlock_irqrestore(&cp->view.lock, flags);
336 
337 	/* Start keyboard reset command. */
338 	raw3270_request_reset(cp->kreset);
339 	raw3270_request_set_cmd(cp->kreset, TC_WRITE);
340 	raw3270_request_add_data(cp->kreset, &kreset_data, 1);
341 	raw3270_start(&cp->view, cp->kreset);
342 
343 	if (deactivate)
344 		raw3270_deactivate_view(&cp->view);
345 
346 	raw3270_request_reset(rrq);
347 	xchg(&cp->read, rrq);
348 	raw3270_put_view(&cp->view);
349 }
350 
351 /*
352  * Read request completion callback.
353  */
354 static void
355 con3270_read_callback(struct raw3270_request *rq, void *data)
356 {
357 	raw3270_get_view(rq->view);
358 	/* Schedule tasklet to pass input to tty. */
359 	tasklet_schedule(&((struct con3270 *) rq->view)->readlet);
360 }
361 
362 /*
363  * Issue a read request. Called only from interrupt function.
364  */
365 static void
366 con3270_issue_read(struct con3270 *cp)
367 {
368 	struct raw3270_request *rrq;
369 	int rc;
370 
371 	rrq = xchg(&cp->read, 0);
372 	if (!rrq)
373 		/* Read already scheduled. */
374 		return;
375 	rrq->callback = con3270_read_callback;
376 	rrq->callback_data = cp;
377 	raw3270_request_set_cmd(rrq, TC_READMOD);
378 	raw3270_request_set_data(rrq, cp->input->string, cp->input->len);
379 	/* Issue the read modified request. */
380 	rc = raw3270_start_irq(&cp->view, rrq);
381 	if (rc)
382 		raw3270_request_reset(rrq);
383 }
384 
385 /*
386  * Switch to the console view.
387  */
388 static int
389 con3270_activate(struct raw3270_view *view)
390 {
391 	struct con3270 *cp;
392 
393 	cp = (struct con3270 *) view;
394 	cp->update_flags = CON_UPDATE_ALL;
395 	con3270_set_timer(cp, 1);
396 	return 0;
397 }
398 
399 static void
400 con3270_deactivate(struct raw3270_view *view)
401 {
402 	struct con3270 *cp;
403 
404 	cp = (struct con3270 *) view;
405 	del_timer(&cp->timer);
406 }
407 
408 static void
409 con3270_irq(struct con3270 *cp, struct raw3270_request *rq, struct irb *irb)
410 {
411 	/* Handle ATTN. Schedule tasklet to read aid. */
412 	if (irb->scsw.cmd.dstat & DEV_STAT_ATTENTION)
413 		con3270_issue_read(cp);
414 
415 	if (rq) {
416 		if (irb->scsw.cmd.dstat & DEV_STAT_UNIT_CHECK)
417 			rq->rc = -EIO;
418 		else
419 			/* Normal end. Copy residual count. */
420 			rq->rescnt = irb->scsw.cmd.count;
421 	} else if (irb->scsw.cmd.dstat & DEV_STAT_DEV_END) {
422 		/* Interrupt without an outstanding request -> update all */
423 		cp->update_flags = CON_UPDATE_ALL;
424 		con3270_set_timer(cp, 1);
425 	}
426 }
427 
428 /* Console view to a 3270 device. */
429 static struct raw3270_fn con3270_fn = {
430 	.activate = con3270_activate,
431 	.deactivate = con3270_deactivate,
432 	.intv = (void *) con3270_irq
433 };
434 
435 static inline void
436 con3270_cline_add(struct con3270 *cp)
437 {
438 	if (!list_empty(&cp->cline->list))
439 		/* Already added. */
440 		return;
441 	list_add_tail(&cp->cline->list, &cp->lines);
442 	cp->nr_lines++;
443 	con3270_rebuild_update(cp);
444 }
445 
446 static inline void
447 con3270_cline_insert(struct con3270 *cp, unsigned char c)
448 {
449 	cp->cline->string[cp->cline->len++] =
450 		cp->view.ascebc[(c < ' ') ? ' ' : c];
451 	if (list_empty(&cp->cline->update)) {
452 		list_add_tail(&cp->cline->update, &cp->update);
453 		cp->update_flags |= CON_UPDATE_LIST;
454 	}
455 }
456 
457 static inline void
458 con3270_cline_end(struct con3270 *cp)
459 {
460 	struct string *s;
461 	unsigned int size;
462 
463 	/* Copy cline. */
464 	size = (cp->cline->len < cp->view.cols - 5) ?
465 		cp->cline->len + 4 : cp->view.cols;
466 	s = con3270_alloc_string(cp, size);
467 	memcpy(s->string, cp->cline->string, cp->cline->len);
468 	if (cp->cline->len < cp->view.cols - 5) {
469 		s->string[s->len - 4] = TO_RA;
470 		s->string[s->len - 1] = 0;
471 	} else {
472 		while (--size >= cp->cline->len)
473 			s->string[size] = cp->view.ascebc[' '];
474 	}
475 	/* Replace cline with allocated line s and reset cline. */
476 	list_add(&s->list, &cp->cline->list);
477 	list_del_init(&cp->cline->list);
478 	if (!list_empty(&cp->cline->update)) {
479 		list_add(&s->update, &cp->cline->update);
480 		list_del_init(&cp->cline->update);
481 	}
482 	cp->cline->len = 0;
483 }
484 
485 /*
486  * Write a string to the 3270 console
487  */
488 static void
489 con3270_write(struct console *co, const char *str, unsigned int count)
490 {
491 	struct con3270 *cp;
492 	unsigned long flags;
493 	unsigned char c;
494 
495 	cp = condev;
496 	spin_lock_irqsave(&cp->view.lock, flags);
497 	while (count-- > 0) {
498 		c = *str++;
499 		if (cp->cline->len == 0)
500 			con3270_cline_add(cp);
501 		if (c != '\n')
502 			con3270_cline_insert(cp, c);
503 		if (c == '\n' || cp->cline->len >= cp->view.cols)
504 			con3270_cline_end(cp);
505 	}
506 	/* Setup timer to output current console buffer after 1/10 second */
507 	cp->nr_up = 0;
508 	if (cp->view.dev && !timer_pending(&cp->timer))
509 		con3270_set_timer(cp, HZ/10);
510 	spin_unlock_irqrestore(&cp->view.lock,flags);
511 }
512 
513 static struct tty_driver *
514 con3270_device(struct console *c, int *index)
515 {
516 	*index = c->index;
517 	return tty3270_driver;
518 }
519 
520 /*
521  * Wait for end of write request.
522  */
523 static void
524 con3270_wait_write(struct con3270 *cp)
525 {
526 	while (!cp->write) {
527 		raw3270_wait_cons_dev(cp->view.dev);
528 		barrier();
529 	}
530 }
531 
532 /*
533  * panic() calls con3270_flush through a panic_notifier
534  * before the system enters a disabled, endless loop.
535  */
536 static void
537 con3270_flush(void)
538 {
539 	struct con3270 *cp;
540 	unsigned long flags;
541 
542 	cp = condev;
543 	if (!cp->view.dev)
544 		return;
545 	raw3270_pm_unfreeze(&cp->view);
546 	raw3270_activate_view(&cp->view);
547 	spin_lock_irqsave(&cp->view.lock, flags);
548 	con3270_wait_write(cp);
549 	cp->nr_up = 0;
550 	con3270_rebuild_update(cp);
551 	con3270_update_status(cp);
552 	while (cp->update_flags != 0) {
553 		spin_unlock_irqrestore(&cp->view.lock, flags);
554 		con3270_update(cp);
555 		spin_lock_irqsave(&cp->view.lock, flags);
556 		con3270_wait_write(cp);
557 	}
558 	spin_unlock_irqrestore(&cp->view.lock, flags);
559 }
560 
561 static int con3270_notify(struct notifier_block *self,
562 			  unsigned long event, void *data)
563 {
564 	con3270_flush();
565 	return NOTIFY_OK;
566 }
567 
568 static struct notifier_block on_panic_nb = {
569 	.notifier_call = con3270_notify,
570 	.priority = 0,
571 };
572 
573 static struct notifier_block on_reboot_nb = {
574 	.notifier_call = con3270_notify,
575 	.priority = 0,
576 };
577 
578 /*
579  *  The console structure for the 3270 console
580  */
581 static struct console con3270 = {
582 	.name	 = "tty3270",
583 	.write	 = con3270_write,
584 	.device	 = con3270_device,
585 	.flags	 = CON_PRINTBUFFER,
586 };
587 
588 /*
589  * 3270 console initialization code called from console_init().
590  */
591 static int __init
592 con3270_init(void)
593 {
594 	struct raw3270 *rp;
595 	void *cbuf;
596 	int i;
597 
598 	/* Check if 3270 is to be the console */
599 	if (!CONSOLE_IS_3270)
600 		return -ENODEV;
601 
602 	/* Set the console mode for VM */
603 	if (MACHINE_IS_VM) {
604 		cpcmd("TERM CONMODE 3270", NULL, 0, NULL);
605 		cpcmd("TERM AUTOCR OFF", NULL, 0, NULL);
606 	}
607 
608 	rp = raw3270_setup_console();
609 	if (IS_ERR(rp))
610 		return PTR_ERR(rp);
611 
612 	condev = kzalloc(sizeof(struct con3270), GFP_KERNEL | GFP_DMA);
613 	if (!condev)
614 		return -ENOMEM;
615 	condev->view.dev = rp;
616 
617 	condev->read = raw3270_request_alloc(0);
618 	condev->read->callback = con3270_read_callback;
619 	condev->read->callback_data = condev;
620 	condev->write = raw3270_request_alloc(CON3270_OUTPUT_BUFFER_SIZE);
621 	condev->kreset = raw3270_request_alloc(1);
622 
623 	INIT_LIST_HEAD(&condev->lines);
624 	INIT_LIST_HEAD(&condev->update);
625 	setup_timer(&condev->timer, (void (*)(unsigned long)) con3270_update,
626 		    (unsigned long) condev);
627 	tasklet_init(&condev->readlet,
628 		     (void (*)(unsigned long)) con3270_read_tasklet,
629 		     (unsigned long) condev->read);
630 
631 	raw3270_add_view(&condev->view, &con3270_fn, 1);
632 
633 	INIT_LIST_HEAD(&condev->freemem);
634 	for (i = 0; i < CON3270_STRING_PAGES; i++) {
635 		cbuf = (void *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
636 		add_string_memory(&condev->freemem, cbuf, PAGE_SIZE);
637 	}
638 	condev->cline = alloc_string(&condev->freemem, condev->view.cols);
639 	condev->cline->len = 0;
640 	con3270_create_status(condev);
641 	condev->input = alloc_string(&condev->freemem, 80);
642 	atomic_notifier_chain_register(&panic_notifier_list, &on_panic_nb);
643 	register_reboot_notifier(&on_reboot_nb);
644 	register_console(&con3270);
645 	return 0;
646 }
647 
648 console_initcall(con3270_init);
649