summaryrefslogtreecommitdiffstats
path: root/drivers/s390/char/fs3270.c
blob: 40759c33477d1d38bca2400f034affbf24e3efcc (plain)
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
/*
 *  drivers/s390/char/fs3270.c
 *    IBM/3270 Driver - fullscreen driver.
 *
 *  Author(s):
 *    Original 3270 Code for 2.4 written by Richard Hitt (UTS Global)
 *    Rewritten for 2.5/2.6 by Martin Schwidefsky <schwidefsky@de.ibm.com>
 *	-- Copyright (C) 2003 IBM Deutschland Entwicklung GmbH, IBM Corporation
 */

#include <linux/bootmem.h>
#include <linux/console.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/list.h>
#include <linux/types.h>
#include <linux/smp_lock.h>

#include <asm/ccwdev.h>
#include <asm/cio.h>
#include <asm/ebcdic.h>
#include <asm/idals.h>

#include "raw3270.h"
#include "ctrlchar.h"

static struct raw3270_fn fs3270_fn;

struct fs3270 {
	struct raw3270_view view;
	struct pid *fs_pid;		/* Pid of controlling program. */
	int read_command;		/* ccw command to use for reads. */
	int write_command;		/* ccw command to use for writes. */
	int attention;			/* Got attention. */
	int active;			/* Fullscreen view is active. */
	struct raw3270_request *init;	/* single init request. */
	wait_queue_head_t wait;		/* Init & attention wait queue. */
	struct idal_buffer *rdbuf;	/* full-screen-deactivate buffer */
	size_t rdbuf_size;		/* size of data returned by RDBUF */
};

static void
fs3270_wake_up(struct raw3270_request *rq, void *data)
{
	wake_up((wait_queue_head_t *) data);
}

static inline int
fs3270_working(struct fs3270 *fp)
{
	/*
	 * The fullscreen view is in working order if the view
	 * has been activated AND the initial request is finished.
	 */
	return fp->active && raw3270_request_final(fp->init);
}

static int
fs3270_do_io(struct raw3270_view *view, struct raw3270_request *rq)
{
	struct fs3270 *fp;
	int rc;

	fp = (struct fs3270 *) view;
	rq->callback = fs3270_wake_up;
	rq->callback_data = &fp->wait;

	do {
		if (!fs3270_working(fp)) {
			/* Fullscreen view isn't ready yet. */
			rc = wait_event_interruptible(fp->wait,
						      fs3270_working(fp));
			if (rc != 0)
				break;
		}
		rc = raw3270_start(view, rq);
		if (rc == 0) {
			/* Started sucessfully. Now wait for completion. */
			wait_event(fp->wait, raw3270_request_final(rq));
		}
	} while (rc == -EACCES);
	return rc;
}

/*
 * Switch to the fullscreen view.
 */
static void
fs3270_reset_callback(struct raw3270_request *rq, void *data)
{
	struct fs3270 *fp;

	fp = (struct fs3270 *) rq->view;
	raw3270_request_reset(rq);
	wake_up(&fp->wait);
}

static void
fs3270_restore_callback(struct raw3270_request *rq, void *data)
{
	struct fs3270 *fp;

	fp = (struct fs3270 *) rq->view;
	if (rq->rc != 0 || rq->rescnt != 0) {
		if (fp->fs_pid)
			kill_pid(fp->fs_pid, SIGHUP, 1);
	}
	fp->rdbuf_size = 0;
	raw3270_request_reset(rq);
	wake_up(&fp->wait);
}

static int
fs3270_activate(struct raw3270_view *view)
{
	struct fs3270 *fp;
	char *cp;
	int rc;

	fp = (struct fs3270 *) view;

	/* If an old init command is still running just return. */
	if (!raw3270_request_final(fp->init))
		return 0;

	if (fp->rdbuf_size == 0) {
		/* No saved buffer. Just clear the screen. */
		raw3270_request_set_cmd(fp->init, TC_EWRITEA);
		fp->init->callback = fs3270_reset_callback;
	} else {
		/* Restore fullscreen buffer saved by fs3270_deactivate. */
		raw3270_request_set_cmd(fp->init, TC_EWRITEA);
		raw3270_request_set_idal(fp->init, fp->rdbuf);
		fp->init->ccw.count = fp->rdbuf_size;
		cp = fp->rdbuf->data[0];
		cp[0] = TW_KR;
		cp[1] = TO_SBA;
		cp[2] = cp[6];
		cp[3] = cp[7];
		cp[4] = TO_IC;
		cp[5] = TO_SBA;
		cp[6] = 0x40;
		cp[7] = 0x40;
		fp->init->rescnt = 0;
		fp->init->callback = fs3270_restore_callback;
	}
	rc = fp->init->rc = raw3270_start_locked(view, fp->init);
	if (rc)
		fp->init->callback(fp->init, NULL);
	else
		fp->active = 1;
	return rc;
}

/*
 * Shutdown fullscreen view.
 */
static void
fs3270_save_callback(struct raw3270_request *rq, void *data)
{
	struct fs3270 *fp;

	fp = (struct fs3270 *) rq->view;

	/* Correct idal buffer element 0 address. */
	fp->rdbuf->data[0] -= 5;
	fp->rdbuf->size += 5;

	/*
	 * If the rdbuf command failed or the idal buffer is
	 * to small for the amount of data returned by the
	 * rdbuf command, then we have no choice but to send
	 * a SIGHUP to the application.
	 */
	if (rq->rc != 0 || rq->rescnt == 0) {
		if (fp->fs_pid)
			kill_pid(fp->fs_pid, SIGHUP, 1);
		fp->rdbuf_size = 0;
	} else
		fp->rdbuf_size = fp->rdbuf->size - rq->rescnt;
	raw3270_request_reset(rq);
	wake_up(&fp->wait);
}

static void
fs3270_deactivate(struct raw3270_view *view)
{
	struct fs3270 *fp;

	fp = (struct fs3270 *) view;
	fp->active = 0;

	/* If an old init command is still running just return. */
	if (!raw3270_request_final(fp->init))
		return;

	/* Prepare read-buffer request. */
	raw3270_request_set_cmd(fp->init, TC_RDBUF);
	/*
	 * Hackish: skip first 5 bytes of the idal buffer to make
	 * room for the TW_KR/TO_SBA/<address>/<address>/TO_IC sequence
	 * in the activation command.
	 */
	fp->rdbuf->data[0] += 5;
	fp->rdbuf->size -= 5;
	raw3270_request_set_idal(fp->init, fp->rdbuf);
	fp->init->rescnt = 0;
	fp->init->callback = fs3270_save_callback;

	/* Start I/O to read in the 3270 buffer. */
	fp->init->rc = raw3270_start_locked(view, fp->init);
	if (fp->init->rc)
		fp->init->callback(fp->init, NULL);
}

static int
fs3270_irq(struct fs3270 *fp, struct raw3270_request *rq, struct irb *irb)
{
	/* Handle ATTN. Set indication and wake waiters for attention. */
	if (irb->scsw.cmd.dstat & DEV_STAT_ATTENTION) {
		fp->attention = 1;
		wake_up(&fp->wait);
	}

	if (rq) {
		if (irb->scsw.cmd.dstat & DEV_STAT_UNIT_CHECK)
			rq->rc = -EIO;
		else
			/* Normal end. Copy residual count. */
			rq->rescnt = irb->scsw.cmd.count;
	}
	return RAW3270_IO_DONE;
}

/*
 * Process reads from fullscreen 3270.
 */
static ssize_t
fs3270_read(struct file *filp, char __user *data, size_t count, loff_t *off)
{
	struct fs3270 *fp;
	struct raw3270_request *rq;
	struct idal_buffer *ib;
	ssize_t rc;
	
	if (count == 0 || count > 65535)
		return -EINVAL;
	fp = filp->private_data;
	if (!fp)
		return -ENODEV;
	ib = idal_buffer_alloc(count, 0);
	if (IS_ERR(ib))
		return -ENOMEM;
	rq = raw3270_request_alloc(0);
	if (!IS_ERR(rq)) {
		if (fp->read_command == 0 && fp->write_command != 0)
			fp->read_command = 6;
		raw3270_request_set_cmd(rq, fp->read_command ? : 2);
		raw3270_request_set_idal(rq, ib);
		rc = wait_event_interruptible(fp->wait, fp->attention);
		fp->attention = 0;
		if (rc == 0) {
			rc = fs3270_do_io(&fp->view, rq);
			if (rc == 0) {
				count -= rq->rescnt;
				if (idal_buffer_to_user(ib, data, count) != 0)
					rc = -EFAULT;
				else
					rc = count;

			}
		}
		raw3270_request_free(rq);
	} else
		rc = PTR_ERR(rq);
	idal_buffer_free(ib);
	return rc;
}

/*
 * Process writes to fullscreen 3270.
 */
static ssize_t
fs3270_write(struct file *filp, const char __user *data, size_t count, loff_t *off)
{
	struct fs3270 *fp;
	struct raw3270_request *rq;
	struct idal_buffer *ib;
	int write_command;
	ssize_t rc;

	fp = filp->private_data;
	if (!fp)
		return -ENODEV;
	ib = idal_buffer_alloc(count, 0);
	if (IS_ERR(ib))
		return -ENOMEM;
	rq = raw3270_request_alloc(0);
	if (!IS_ERR(rq)) {
		if (idal_buffer_from_user(ib, data, count) == 0) {
			write_command = fp->write_command ? : 1;
			if (write_command == 5)
				write_command = 13;
			raw3270_request_set_cmd(rq, write_command);
			raw3270_request_set_idal(rq, ib);
			rc = fs3270_do_io(&fp->view, rq);
			if (rc == 0)
				rc = count - rq->rescnt;
		} else
			rc = -EFAULT;
		raw3270_request_free(rq);
	} else
		rc = PTR_ERR(rq);
	idal_buffer_free(ib);
	return rc;
}

/*
 * process ioctl commands for the tube driver
 */
static long
fs3270_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
{
	struct fs3270 *fp;
	struct raw3270_iocb iocb;
	int rc;

	fp = filp->private_data;
	if (!fp)
		return -ENODEV;
	rc = 0;
	lock_kernel();
	switch (cmd) {
	case TUBICMD:
		fp->read_command = arg;
		break;
	case TUBOCMD:
		fp->write_command = arg;
		break;
	case TUBGETI:
		rc = put_user(fp->read_command, (char __user *) arg);
		break;
	case TUBGETO:
		rc = put_user(fp->write_command,(char __user *) arg);
		break;
	case TUBGETMOD:
		iocb.model = fp->view.model;
		iocb.line_cnt = fp->view.rows;
		iocb.col_cnt = fp->view.cols;
		iocb.pf_cnt = 24;
		iocb.re_cnt = 20;
		iocb.map = 0;
		if (copy_to_user((char __user *) arg, &iocb,
				 sizeof(struct raw3270_iocb)))
			rc = -EFAULT;
		break;
	}
	unlock_kernel();
	return rc;
}

/*
 * Allocate fs3270 structure.
 */
static struct fs3270 *
fs3270_alloc_view(void)
{
	struct fs3270 *fp;

	fp = kzalloc(sizeof(struct fs3270),GFP_KERNEL);
	if (!fp)
		return ERR_PTR(-ENOMEM);
	fp->init = raw3270_request_alloc(0);
	if (IS_ERR(fp->init)) {
		kfree(fp);
		return ERR_PTR(-ENOMEM);
	}
	return fp;
}

/*
 * Free fs3270 structure.
 */
static void
fs3270_free_view(struct raw3270_view *view)
{
	struct fs3270 *fp;

	fp = (struct fs3270 *) view;
	if (fp->rdbuf)
		idal_buffer_free(fp->rdbuf);
	raw3270_request_free(((struct fs3270 *) view)->init);
	kfree(view);
}

/*
 * Unlink fs3270 data structure from filp.
 */
static void
fs3270_release(struct raw3270_view *view)
{
}

/* View to a 3270 device. Can be console, tty or fullscreen. */
static struct raw3270_fn fs3270_fn = {
	.activate = fs3270_activate,
	.deactivate = fs3270_deactivate,
	.intv = (void *) fs3270_irq,
	.release = fs3270_release,
	.free = fs3270_free_view
};

/*
 * This routine is called whenever a 3270 fullscreen device is opened.
 */
static int
fs3270_open(struct inode *inode, struct file *filp)
{
	struct fs3270 *fp;
	struct idal_buffer *ib;
	int minor, rc = 0;

	if (imajor(filp->f_path.dentry->d_inode) != IBM_FS3270_MAJOR)
		return -ENODEV;
	minor = iminor(filp->f_path.dentry->d_inode);
	/* Check for minor 0 multiplexer. */
	if (minor == 0) {
		struct tty_struct *tty = get_current_tty();
		if (!tty || tty->driver->major != IBM_TTY3270_MAJOR) {
			tty_kref_put(tty);
			return -ENODEV;
		}
		minor = tty->index + RAW3270_FIRSTMINOR;
		tty_kref_put(tty);
	}
	lock_kernel();
	/* Check if some other program is already using fullscreen mode. */
	fp = (struct fs3270 *) raw3270_find_view(&fs3270_fn, minor);
	if (!IS_ERR(fp)) {
		raw3270_put_view(&fp->view);
		rc = -EBUSY;
		goto out;
	}
	/* Allocate fullscreen view structure. */
	fp = fs3270_alloc_view();
	if (IS_ERR(fp)) {
		rc = PTR_ERR(fp);
		goto out;
	}

	init_waitqueue_head(&fp->wait);
	fp->fs_pid = get_pid(task_pid(current));
	rc = raw3270_add_view(&fp->view, &fs3270_fn, minor);
	if (rc) {
		fs3270_free_view(&fp->view);
		goto out;
	}

	/* Allocate idal-buffer. */
	ib = idal_buffer_alloc(2*fp->view.rows*fp->view.cols + 5, 0);
	if (IS_ERR(ib)) {
		raw3270_put_view(&fp->view);
		raw3270_del_view(&fp->view);
		rc = PTR_ERR(fp);
		goto out;
	}
	fp->rdbuf = ib;

	rc = raw3270_activate_view(&fp->view);
	if (rc) {
		raw3270_put_view(&fp->view);
		raw3270_del_view(&fp->view);
		goto out;
	}
	filp->private_data = fp;
out:
	unlock_kernel();
	return rc;
}

/*
 * This routine is called when the 3270 tty is closed. We wait
 * for the remaining request to be completed. Then we clean up.
 */
static int
fs3270_close(struct inode *inode, struct file *filp)
{
	struct fs3270 *fp;

	fp = filp->private_data;
	filp->private_data = NULL;
	if (fp) {
		put_pid(fp->fs_pid);
		fp->fs_pid = NULL;
		raw3270_reset(&fp->view);
		raw3270_put_view(&fp->view);
		raw3270_del_view(&fp->view);
	}
	return 0;
}

static const struct file_operations fs3270_fops = {
	.owner		 = THIS_MODULE,		/* owner */
	.read		 = fs3270_read,		/* read */
	.write		 = fs3270_write,	/* write */
	.unlocked_ioctl	 = fs3270_ioctl,	/* ioctl */
	.compat_ioctl	 = fs3270_ioctl,	/* ioctl */
	.open	 	= fs3270_open,		/* open */
	.release 	= fs3270_close,		/* release */
};

/*
 * 3270 fullscreen driver initialization.
 */
static int __init
fs3270_init(void)
{
	int rc;

	rc = register_chrdev(IBM_FS3270_MAJOR, "fs3270", &fs3270_fops);
	if (rc)
		return rc;
	return 0;
}

static void __exit
fs3270_exit(void)
{
	unregister_chrdev(IBM_FS3270_MAJOR, "fs3270");
}

MODULE_LICENSE("GPL");
MODULE_ALIAS_CHARDEV_MAJOR(IBM_FS3270_MAJOR);

module_init(fs3270_init);
module_exit(fs3270_exit);
OpenPOWER on IntegriCloud