xref: /openbmc/linux/drivers/s390/char/fs3270.c (revision 87c2ce3b) 
1 /*
2  *  drivers/s390/char/fs3270.c
3  *    IBM/3270 Driver - fullscreen driver.
4  *
5  *  Author(s):
6  *    Original 3270 Code for 2.4 written by Richard Hitt (UTS Global)
7  *    Rewritten for 2.5/2.6 by Martin Schwidefsky <schwidefsky@de.ibm.com>
8  *	-- Copyright (C) 2003 IBM Deutschland Entwicklung GmbH, IBM Corporation
9  */
10 
11 #include <linux/config.h>
12 #include <linux/bootmem.h>
13 #include <linux/console.h>
14 #include <linux/init.h>
15 #include <linux/interrupt.h>
16 #include <linux/list.h>
17 #include <linux/types.h>
18 
19 #include <asm/ccwdev.h>
20 #include <asm/cio.h>
21 #include <asm/cpcmd.h>
22 #include <asm/ebcdic.h>
23 #include <asm/idals.h>
24 
25 #include "raw3270.h"
26 #include "ctrlchar.h"
27 
28 struct raw3270_fn fs3270_fn;
29 
30 struct fs3270 {
31 	struct raw3270_view view;
32 	pid_t fs_pid;			/* Pid of controlling program. */
33 	int read_command;		/* ccw command to use for reads. */
34 	int write_command;		/* ccw command to use for writes. */
35 	int attention;			/* Got attention. */
36 	int active;			/* Fullscreen view is active. */
37 	struct raw3270_request *init;	/* single init request. */
38 	wait_queue_head_t wait;		/* Init & attention wait queue. */
39 	struct idal_buffer *rdbuf;	/* full-screen-deactivate buffer */
40 	size_t rdbuf_size;		/* size of data returned by RDBUF */
41 };
42 
43 static void
44 fs3270_wake_up(struct raw3270_request *rq, void *data)
45 {
46 	wake_up((wait_queue_head_t *) data);
47 }
48 
49 static inline int
50 fs3270_working(struct fs3270 *fp)
51 {
52 	/*
53 	 * The fullscreen view is in working order if the view
54 	 * has been activated AND the initial request is finished.
55 	 */
56 	return fp->active && raw3270_request_final(fp->init);
57 }
58 
59 static int
60 fs3270_do_io(struct raw3270_view *view, struct raw3270_request *rq)
61 {
62 	struct fs3270 *fp;
63 	int rc;
64 
65 	fp = (struct fs3270 *) view;
66 	rq->callback = fs3270_wake_up;
67 	rq->callback_data = &fp->wait;
68 
69 	do {
70 		if (!fs3270_working(fp)) {
71 			/* Fullscreen view isn't ready yet. */
72 			rc = wait_event_interruptible(fp->wait,
73 						      fs3270_working(fp));
74 			if (rc != 0)
75 				break;
76 		}
77 		rc = raw3270_start(view, rq);
78 		if (rc == 0) {
79 			/* Started sucessfully. Now wait for completion. */
80 			wait_event(fp->wait, raw3270_request_final(rq));
81 		}
82 	} while (rc == -EACCES);
83 	return rc;
84 }
85 
86 /*
87  * Switch to the fullscreen view.
88  */
89 static void
90 fs3270_reset_callback(struct raw3270_request *rq, void *data)
91 {
92 	struct fs3270 *fp;
93 
94 	fp = (struct fs3270 *) rq->view;
95 	raw3270_request_reset(rq);
96 	wake_up(&fp->wait);
97 }
98 
99 static void
100 fs3270_restore_callback(struct raw3270_request *rq, void *data)
101 {
102 	struct fs3270 *fp;
103 
104 	fp = (struct fs3270 *) rq->view;
105 	if (rq->rc != 0 || rq->rescnt != 0) {
106 		if (fp->fs_pid)
107 			kill_proc(fp->fs_pid, SIGHUP, 1);
108 	}
109 	fp->rdbuf_size = 0;
110 	raw3270_request_reset(rq);
111 	wake_up(&fp->wait);
112 }
113 
114 static int
115 fs3270_activate(struct raw3270_view *view)
116 {
117 	struct fs3270 *fp;
118 	char *cp;
119 	int rc;
120 
121 	fp = (struct fs3270 *) view;
122 
123 	/* If an old init command is still running just return. */
124 	if (!raw3270_request_final(fp->init))
125 		return 0;
126 
127 	if (fp->rdbuf_size == 0) {
128 		/* No saved buffer. Just clear the screen. */
129 		raw3270_request_set_cmd(fp->init, TC_EWRITEA);
130 		fp->init->callback = fs3270_reset_callback;
131 	} else {
132 		/* Restore fullscreen buffer saved by fs3270_deactivate. */
133 		raw3270_request_set_cmd(fp->init, TC_EWRITEA);
134 		raw3270_request_set_idal(fp->init, fp->rdbuf);
135 		fp->init->ccw.count = fp->rdbuf_size;
136 		cp = fp->rdbuf->data[0];
137 		cp[0] = TW_KR;
138 		cp[1] = TO_SBA;
139 		cp[2] = cp[6];
140 		cp[3] = cp[7];
141 		cp[4] = TO_IC;
142 		cp[5] = TO_SBA;
143 		cp[6] = 0x40;
144 		cp[7] = 0x40;
145 		fp->init->rescnt = 0;
146 		fp->init->callback = fs3270_restore_callback;
147 	}
148 	rc = fp->init->rc = raw3270_start_locked(view, fp->init);
149 	if (rc)
150 		fp->init->callback(fp->init, NULL);
151 	else
152 		fp->active = 1;
153 	return rc;
154 }
155 
156 /*
157  * Shutdown fullscreen view.
158  */
159 static void
160 fs3270_save_callback(struct raw3270_request *rq, void *data)
161 {
162 	struct fs3270 *fp;
163 
164 	fp = (struct fs3270 *) rq->view;
165 
166 	/* Correct idal buffer element 0 address. */
167 	fp->rdbuf->data[0] -= 5;
168 	fp->rdbuf->size += 5;
169 
170 	/*
171 	 * If the rdbuf command failed or the idal buffer is
172 	 * to small for the amount of data returned by the
173 	 * rdbuf command, then we have no choice but to send
174 	 * a SIGHUP to the application.
175 	 */
176 	if (rq->rc != 0 || rq->rescnt == 0) {
177 		if (fp->fs_pid)
178 			kill_proc(fp->fs_pid, SIGHUP, 1);
179 		fp->rdbuf_size = 0;
180 	} else
181 		fp->rdbuf_size = fp->rdbuf->size - rq->rescnt;
182 	raw3270_request_reset(rq);
183 	wake_up(&fp->wait);
184 }
185 
186 static void
187 fs3270_deactivate(struct raw3270_view *view)
188 {
189 	struct fs3270 *fp;
190 
191 	fp = (struct fs3270 *) view;
192 	fp->active = 0;
193 
194 	/* If an old init command is still running just return. */
195 	if (!raw3270_request_final(fp->init))
196 		return;
197 
198 	/* Prepare read-buffer request. */
199 	raw3270_request_set_cmd(fp->init, TC_RDBUF);
200 	/*
201 	 * Hackish: skip first 5 bytes of the idal buffer to make
202 	 * room for the TW_KR/TO_SBA/<address>/<address>/TO_IC sequence
203 	 * in the activation command.
204 	 */
205 	fp->rdbuf->data[0] += 5;
206 	fp->rdbuf->size -= 5;
207 	raw3270_request_set_idal(fp->init, fp->rdbuf);
208 	fp->init->rescnt = 0;
209 	fp->init->callback = fs3270_save_callback;
210 
211 	/* Start I/O to read in the 3270 buffer. */
212 	fp->init->rc = raw3270_start_locked(view, fp->init);
213 	if (fp->init->rc)
214 		fp->init->callback(fp->init, NULL);
215 }
216 
217 static int
218 fs3270_irq(struct fs3270 *fp, struct raw3270_request *rq, struct irb *irb)
219 {
220 	/* Handle ATTN. Set indication and wake waiters for attention. */
221 	if (irb->scsw.dstat & DEV_STAT_ATTENTION) {
222 		fp->attention = 1;
223 		wake_up(&fp->wait);
224 	}
225 
226 	if (rq) {
227 		if (irb->scsw.dstat & DEV_STAT_UNIT_CHECK)
228 			rq->rc = -EIO;
229 		else
230 			/* Normal end. Copy residual count. */
231 			rq->rescnt = irb->scsw.count;
232 	}
233 	return RAW3270_IO_DONE;
234 }
235 
236 /*
237  * Process reads from fullscreen 3270.
238  */
239 static ssize_t
240 fs3270_read(struct file *filp, char *data, size_t count, loff_t *off)
241 {
242 	struct fs3270 *fp;
243 	struct raw3270_request *rq;
244 	struct idal_buffer *ib;
245 	ssize_t rc;
246 
247 	if (count == 0 || count > 65535)
248 		return -EINVAL;
249 	fp = filp->private_data;
250 	if (!fp)
251 		return -ENODEV;
252 	ib = idal_buffer_alloc(count, 0);
253 	if (IS_ERR(ib))
254 		return -ENOMEM;
255 	rq = raw3270_request_alloc(0);
256 	if (!IS_ERR(rq)) {
257 		if (fp->read_command == 0 && fp->write_command != 0)
258 			fp->read_command = 6;
259 		raw3270_request_set_cmd(rq, fp->read_command ? : 2);
260 		raw3270_request_set_idal(rq, ib);
261 		rc = wait_event_interruptible(fp->wait, fp->attention);
262 		fp->attention = 0;
263 		if (rc == 0) {
264 			rc = fs3270_do_io(&fp->view, rq);
265 			if (rc == 0) {
266 				count -= rq->rescnt;
267 				if (idal_buffer_to_user(ib, data, count) != 0)
268 					rc = -EFAULT;
269 				else
270 					rc = count;
271 
272 			}
273 		}
274 		raw3270_request_free(rq);
275 	} else
276 		rc = PTR_ERR(rq);
277 	idal_buffer_free(ib);
278 	return rc;
279 }
280 
281 /*
282  * Process writes to fullscreen 3270.
283  */
284 static ssize_t
285 fs3270_write(struct file *filp, const char *data, size_t count, loff_t *off)
286 {
287 	struct fs3270 *fp;
288 	struct raw3270_request *rq;
289 	struct idal_buffer *ib;
290 	int write_command;
291 	ssize_t rc;
292 
293 	fp = filp->private_data;
294 	if (!fp)
295 		return -ENODEV;
296 	ib = idal_buffer_alloc(count, 0);
297 	if (IS_ERR(ib))
298 		return -ENOMEM;
299 	rq = raw3270_request_alloc(0);
300 	if (!IS_ERR(rq)) {
301 		if (idal_buffer_from_user(ib, data, count) == 0) {
302 			write_command = fp->write_command ? : 1;
303 			if (write_command == 5)
304 				write_command = 13;
305 			raw3270_request_set_cmd(rq, write_command);
306 			raw3270_request_set_idal(rq, ib);
307 			rc = fs3270_do_io(&fp->view, rq);
308 			if (rc == 0)
309 				rc = count - rq->rescnt;
310 		} else
311 			rc = -EFAULT;
312 		raw3270_request_free(rq);
313 	} else
314 		rc = PTR_ERR(rq);
315 	idal_buffer_free(ib);
316 	return rc;
317 }
318 
319 /*
320  * process ioctl commands for the tube driver
321  */
322 static long
323 fs3270_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
324 {
325 	struct fs3270 *fp;
326 	struct raw3270_iocb iocb;
327 	int rc;
328 
329 	fp = filp->private_data;
330 	if (!fp)
331 		return -ENODEV;
332 	rc = 0;
333 	lock_kernel();
334 	switch (cmd) {
335 	case TUBICMD:
336 		fp->read_command = arg;
337 		break;
338 	case TUBOCMD:
339 		fp->write_command = arg;
340 		break;
341 	case TUBGETI:
342 		rc = put_user(fp->read_command, (char *) arg);
343 		break;
344 	case TUBGETO:
345 		rc = put_user(fp->write_command,(char *) arg);
346 		break;
347 	case TUBGETMOD:
348 		iocb.model = fp->view.model;
349 		iocb.line_cnt = fp->view.rows;
350 		iocb.col_cnt = fp->view.cols;
351 		iocb.pf_cnt = 24;
352 		iocb.re_cnt = 20;
353 		iocb.map = 0;
354 		if (copy_to_user((char *) arg, &iocb,
355 				 sizeof(struct raw3270_iocb)))
356 			rc = -EFAULT;
357 		break;
358 	}
359 	unlock_kernel();
360 	return rc;
361 }
362 
363 /*
364  * Allocate fs3270 structure.
365  */
366 static struct fs3270 *
367 fs3270_alloc_view(void)
368 {
369 	struct fs3270 *fp;
370 
371 	fp = (struct fs3270 *) kmalloc(sizeof(struct fs3270),GFP_KERNEL);
372 	if (!fp)
373 		return ERR_PTR(-ENOMEM);
374 	memset(fp, 0, sizeof(struct fs3270));
375 	fp->init = raw3270_request_alloc(0);
376 	if (IS_ERR(fp->init)) {
377 		kfree(fp);
378 		return ERR_PTR(-ENOMEM);
379 	}
380 	return fp;
381 }
382 
383 /*
384  * Free fs3270 structure.
385  */
386 static void
387 fs3270_free_view(struct raw3270_view *view)
388 {
389 	struct fs3270 *fp;
390 
391 	fp = (struct fs3270 *) view;
392 	if (fp->rdbuf)
393 		idal_buffer_free(fp->rdbuf);
394 	raw3270_request_free(((struct fs3270 *) view)->init);
395 	kfree(view);
396 }
397 
398 /*
399  * Unlink fs3270 data structure from filp.
400  */
401 static void
402 fs3270_release(struct raw3270_view *view)
403 {
404 }
405 
406 /* View to a 3270 device. Can be console, tty or fullscreen. */
407 struct raw3270_fn fs3270_fn = {
408 	.activate = fs3270_activate,
409 	.deactivate = fs3270_deactivate,
410 	.intv = (void *) fs3270_irq,
411 	.release = fs3270_release,
412 	.free = fs3270_free_view
413 };
414 
415 /*
416  * This routine is called whenever a 3270 fullscreen device is opened.
417  */
418 static int
419 fs3270_open(struct inode *inode, struct file *filp)
420 {
421 	struct fs3270 *fp;
422 	struct idal_buffer *ib;
423 	int minor, rc;
424 
425 	if (imajor(filp->f_dentry->d_inode) != IBM_FS3270_MAJOR)
426 		return -ENODEV;
427 	minor = iminor(filp->f_dentry->d_inode);
428 	/* Check for minor 0 multiplexer. */
429 	if (minor == 0) {
430 		if (!current->signal->tty)
431 			return -ENODEV;
432 		if (current->signal->tty->driver->major != IBM_TTY3270_MAJOR)
433 			return -ENODEV;
434 		minor = current->signal->tty->index + RAW3270_FIRSTMINOR;
435 	}
436 	/* Check if some other program is already using fullscreen mode. */
437 	fp = (struct fs3270 *) raw3270_find_view(&fs3270_fn, minor);
438 	if (!IS_ERR(fp)) {
439 		raw3270_put_view(&fp->view);
440 		return -EBUSY;
441 	}
442 	/* Allocate fullscreen view structure. */
443 	fp = fs3270_alloc_view();
444 	if (IS_ERR(fp))
445 		return PTR_ERR(fp);
446 
447 	init_waitqueue_head(&fp->wait);
448 	fp->fs_pid = current->pid;
449 	rc = raw3270_add_view(&fp->view, &fs3270_fn, minor);
450 	if (rc) {
451 		fs3270_free_view(&fp->view);
452 		return rc;
453 	}
454 
455 	/* Allocate idal-buffer. */
456 	ib = idal_buffer_alloc(2*fp->view.rows*fp->view.cols + 5, 0);
457 	if (IS_ERR(ib)) {
458 		raw3270_put_view(&fp->view);
459 		raw3270_del_view(&fp->view);
460 		return PTR_ERR(fp);
461 	}
462 	fp->rdbuf = ib;
463 
464 	rc = raw3270_activate_view(&fp->view);
465 	if (rc) {
466 		raw3270_put_view(&fp->view);
467 		raw3270_del_view(&fp->view);
468 		return rc;
469 	}
470 	filp->private_data = fp;
471 	return 0;
472 }
473 
474 /*
475  * This routine is called when the 3270 tty is closed. We wait
476  * for the remaining request to be completed. Then we clean up.
477  */
478 static int
479 fs3270_close(struct inode *inode, struct file *filp)
480 {
481 	struct fs3270 *fp;
482 
483 	fp = filp->private_data;
484 	filp->private_data = 0;
485 	if (fp) {
486 		fp->fs_pid = 0;
487 		raw3270_reset(&fp->view);
488 		raw3270_put_view(&fp->view);
489 		raw3270_del_view(&fp->view);
490 	}
491 	return 0;
492 }
493 
494 static struct file_operations fs3270_fops = {
495 	.owner		 = THIS_MODULE,		/* owner */
496 	.read		 = fs3270_read,		/* read */
497 	.write		 = fs3270_write,	/* write */
498 	.unlocked_ioctl	 = fs3270_ioctl,	/* ioctl */
499 	.compat_ioctl	 = fs3270_ioctl,	/* ioctl */
500 	.open	 	= fs3270_open,		/* open */
501 	.release 	= fs3270_close,		/* release */
502 };
503 
504 /*
505  * 3270 fullscreen driver initialization.
506  */
507 static int __init
508 fs3270_init(void)
509 {
510 	int rc;
511 
512 	rc = register_chrdev(IBM_FS3270_MAJOR, "fs3270", &fs3270_fops);
513 	if (rc) {
514 		printk(KERN_ERR "fs3270 can't get major number %d: errno %d\n",
515 		       IBM_FS3270_MAJOR, rc);
516 		return rc;
517 	}
518 	return 0;
519 }
520 
521 static void __exit
522 fs3270_exit(void)
523 {
524 	unregister_chrdev(IBM_FS3270_MAJOR, "fs3270");
525 }
526 
527 MODULE_LICENSE("GPL");
528 MODULE_ALIAS_CHARDEV_MAJOR(IBM_FS3270_MAJOR);
529 
530 module_init(fs3270_init);
531 module_exit(fs3270_exit);
532