1 /*
2 * IBM/3270 Driver - fullscreen driver.
3 *
4 * Author(s):
5 * Original 3270 Code for 2.4 written by Richard Hitt (UTS Global)
6 * Rewritten for 2.5/2.6 by Martin Schwidefsky <schwidefsky@de.ibm.com>
7 * Copyright IBM Corp. 2003, 2009
8 */
9
10 #include <linux/bootmem.h>
11 #include <linux/console.h>
12 #include <linux/init.h>
13 #include <linux/interrupt.h>
14 #include <linux/list.h>
15 #include <linux/slab.h>
16 #include <linux/types.h>
17
18 #include <asm/compat.h>
19 #include <asm/ccwdev.h>
20 #include <asm/cio.h>
21 #include <asm/ebcdic.h>
22 #include <asm/idals.h>
23
24 #include "raw3270.h"
25 #include "ctrlchar.h"
26
27 static struct raw3270_fn fs3270_fn;
28
29 struct fs3270 {
30 struct raw3270_view view;
31 struct pid *fs_pid; /* Pid of controlling program. */
32 int read_command; /* ccw command to use for reads. */
33 int write_command; /* ccw command to use for writes. */
34 int attention; /* Got attention. */
35 int active; /* Fullscreen view is active. */
36 struct raw3270_request *init; /* single init request. */
37 wait_queue_head_t wait; /* Init & attention wait queue. */
38 struct idal_buffer *rdbuf; /* full-screen-deactivate buffer */
39 size_t rdbuf_size; /* size of data returned by RDBUF */
40 };
41
42 static DEFINE_MUTEX(fs3270_mutex);
43
44 static void
fs3270_wake_up(struct raw3270_request * rq,void * data)45 fs3270_wake_up(struct raw3270_request *rq, void *data)
46 {
47 wake_up((wait_queue_head_t *) data);
48 }
49
50 static inline int
fs3270_working(struct fs3270 * fp)51 fs3270_working(struct fs3270 *fp)
52 {
53 /*
54 * The fullscreen view is in working order if the view
55 * has been activated AND the initial request is finished.
56 */
57 return fp->active && raw3270_request_final(fp->init);
58 }
59
60 static int
fs3270_do_io(struct raw3270_view * view,struct raw3270_request * rq)61 fs3270_do_io(struct raw3270_view *view, struct raw3270_request *rq)
62 {
63 struct fs3270 *fp;
64 int rc;
65
66 fp = (struct fs3270 *) view;
67 rq->callback = fs3270_wake_up;
68 rq->callback_data = &fp->wait;
69
70 do {
71 if (!fs3270_working(fp)) {
72 /* Fullscreen view isn't ready yet. */
73 rc = wait_event_interruptible(fp->wait,
74 fs3270_working(fp));
75 if (rc != 0)
76 break;
77 }
78 rc = raw3270_start(view, rq);
79 if (rc == 0) {
80 /* Started successfully. Now wait for completion. */
81 wait_event(fp->wait, raw3270_request_final(rq));
82 }
83 } while (rc == -EACCES);
84 return rc;
85 }
86
87 /*
88 * Switch to the fullscreen view.
89 */
90 static void
fs3270_reset_callback(struct raw3270_request * rq,void * data)91 fs3270_reset_callback(struct raw3270_request *rq, void *data)
92 {
93 struct fs3270 *fp;
94
95 fp = (struct fs3270 *) rq->view;
96 raw3270_request_reset(rq);
97 wake_up(&fp->wait);
98 }
99
100 static void
fs3270_restore_callback(struct raw3270_request * rq,void * data)101 fs3270_restore_callback(struct raw3270_request *rq, void *data)
102 {
103 struct fs3270 *fp;
104
105 fp = (struct fs3270 *) rq->view;
106 if (rq->rc != 0 || rq->rescnt != 0) {
107 if (fp->fs_pid)
108 kill_pid(fp->fs_pid, SIGHUP, 1);
109 }
110 fp->rdbuf_size = 0;
111 raw3270_request_reset(rq);
112 wake_up(&fp->wait);
113 }
114
115 static int
fs3270_activate(struct raw3270_view * view)116 fs3270_activate(struct raw3270_view *view)
117 {
118 struct fs3270 *fp;
119 char *cp;
120 int rc;
121
122 fp = (struct fs3270 *) view;
123
124 /* If an old init command is still running just return. */
125 if (!raw3270_request_final(fp->init))
126 return 0;
127
128 if (fp->rdbuf_size == 0) {
129 /* No saved buffer. Just clear the screen. */
130 raw3270_request_set_cmd(fp->init, TC_EWRITEA);
131 fp->init->callback = fs3270_reset_callback;
132 } else {
133 /* Restore fullscreen buffer saved by fs3270_deactivate. */
134 raw3270_request_set_cmd(fp->init, TC_EWRITEA);
135 raw3270_request_set_idal(fp->init, fp->rdbuf);
136 fp->init->ccw.count = fp->rdbuf_size;
137 cp = fp->rdbuf->data[0];
138 cp[0] = TW_KR;
139 cp[1] = TO_SBA;
140 cp[2] = cp[6];
141 cp[3] = cp[7];
142 cp[4] = TO_IC;
143 cp[5] = TO_SBA;
144 cp[6] = 0x40;
145 cp[7] = 0x40;
146 fp->init->rescnt = 0;
147 fp->init->callback = fs3270_restore_callback;
148 }
149 rc = fp->init->rc = raw3270_start_locked(view, fp->init);
150 if (rc)
151 fp->init->callback(fp->init, NULL);
152 else
153 fp->active = 1;
154 return rc;
155 }
156
157 /*
158 * Shutdown fullscreen view.
159 */
160 static void
fs3270_save_callback(struct raw3270_request * rq,void * data)161 fs3270_save_callback(struct raw3270_request *rq, void *data)
162 {
163 struct fs3270 *fp;
164
165 fp = (struct fs3270 *) rq->view;
166
167 /* Correct idal buffer element 0 address. */
168 fp->rdbuf->data[0] -= 5;
169 fp->rdbuf->size += 5;
170
171 /*
172 * If the rdbuf command failed or the idal buffer is
173 * to small for the amount of data returned by the
174 * rdbuf command, then we have no choice but to send
175 * a SIGHUP to the application.
176 */
177 if (rq->rc != 0 || rq->rescnt == 0) {
178 if (fp->fs_pid)
179 kill_pid(fp->fs_pid, SIGHUP, 1);
180 fp->rdbuf_size = 0;
181 } else
182 fp->rdbuf_size = fp->rdbuf->size - rq->rescnt;
183 raw3270_request_reset(rq);
184 wake_up(&fp->wait);
185 }
186
187 static void
fs3270_deactivate(struct raw3270_view * view)188 fs3270_deactivate(struct raw3270_view *view)
189 {
190 struct fs3270 *fp;
191
192 fp = (struct fs3270 *) view;
193 fp->active = 0;
194
195 /* If an old init command is still running just return. */
196 if (!raw3270_request_final(fp->init))
197 return;
198
199 /* Prepare read-buffer request. */
200 raw3270_request_set_cmd(fp->init, TC_RDBUF);
201 /*
202 * Hackish: skip first 5 bytes of the idal buffer to make
203 * room for the TW_KR/TO_SBA/<address>/<address>/TO_IC sequence
204 * in the activation command.
205 */
206 fp->rdbuf->data[0] += 5;
207 fp->rdbuf->size -= 5;
208 raw3270_request_set_idal(fp->init, fp->rdbuf);
209 fp->init->rescnt = 0;
210 fp->init->callback = fs3270_save_callback;
211
212 /* Start I/O to read in the 3270 buffer. */
213 fp->init->rc = raw3270_start_locked(view, fp->init);
214 if (fp->init->rc)
215 fp->init->callback(fp->init, NULL);
216 }
217
218 static int
fs3270_irq(struct fs3270 * fp,struct raw3270_request * rq,struct irb * irb)219 fs3270_irq(struct fs3270 *fp, struct raw3270_request *rq, struct irb *irb)
220 {
221 /* Handle ATTN. Set indication and wake waiters for attention. */
222 if (irb->scsw.cmd.dstat & DEV_STAT_ATTENTION) {
223 fp->attention = 1;
224 wake_up(&fp->wait);
225 }
226
227 if (rq) {
228 if (irb->scsw.cmd.dstat & DEV_STAT_UNIT_CHECK)
229 rq->rc = -EIO;
230 else
231 /* Normal end. Copy residual count. */
232 rq->rescnt = irb->scsw.cmd.count;
233 }
234 return RAW3270_IO_DONE;
235 }
236
237 /*
238 * Process reads from fullscreen 3270.
239 */
240 static ssize_t
fs3270_read(struct file * filp,char __user * data,size_t count,loff_t * off)241 fs3270_read(struct file *filp, char __user *data, size_t count, loff_t *off)
242 {
243 struct fs3270 *fp;
244 struct raw3270_request *rq;
245 struct idal_buffer *ib;
246 ssize_t rc;
247
248 if (count == 0 || count > 65535)
249 return -EINVAL;
250 fp = filp->private_data;
251 if (!fp)
252 return -ENODEV;
253 ib = idal_buffer_alloc(count, 0);
254 if (IS_ERR(ib))
255 return -ENOMEM;
256 rq = raw3270_request_alloc(0);
257 if (!IS_ERR(rq)) {
258 if (fp->read_command == 0 && fp->write_command != 0)
259 fp->read_command = 6;
260 raw3270_request_set_cmd(rq, fp->read_command ? : 2);
261 raw3270_request_set_idal(rq, ib);
262 rc = wait_event_interruptible(fp->wait, fp->attention);
263 fp->attention = 0;
264 if (rc == 0) {
265 rc = fs3270_do_io(&fp->view, rq);
266 if (rc == 0) {
267 count -= rq->rescnt;
268 if (idal_buffer_to_user(ib, data, count) != 0)
269 rc = -EFAULT;
270 else
271 rc = count;
272
273 }
274 }
275 raw3270_request_free(rq);
276 } else
277 rc = PTR_ERR(rq);
278 idal_buffer_free(ib);
279 return rc;
280 }
281
282 /*
283 * Process writes to fullscreen 3270.
284 */
285 static ssize_t
fs3270_write(struct file * filp,const char __user * data,size_t count,loff_t * off)286 fs3270_write(struct file *filp, const char __user *data, size_t count, loff_t *off)
287 {
288 struct fs3270 *fp;
289 struct raw3270_request *rq;
290 struct idal_buffer *ib;
291 int write_command;
292 ssize_t rc;
293
294 fp = filp->private_data;
295 if (!fp)
296 return -ENODEV;
297 ib = idal_buffer_alloc(count, 0);
298 if (IS_ERR(ib))
299 return -ENOMEM;
300 rq = raw3270_request_alloc(0);
301 if (!IS_ERR(rq)) {
302 if (idal_buffer_from_user(ib, data, count) == 0) {
303 write_command = fp->write_command ? : 1;
304 if (write_command == 5)
305 write_command = 13;
306 raw3270_request_set_cmd(rq, write_command);
307 raw3270_request_set_idal(rq, ib);
308 rc = fs3270_do_io(&fp->view, rq);
309 if (rc == 0)
310 rc = count - rq->rescnt;
311 } else
312 rc = -EFAULT;
313 raw3270_request_free(rq);
314 } else
315 rc = PTR_ERR(rq);
316 idal_buffer_free(ib);
317 return rc;
318 }
319
320 /*
321 * process ioctl commands for the tube driver
322 */
323 static long
fs3270_ioctl(struct file * filp,unsigned int cmd,unsigned long arg)324 fs3270_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
325 {
326 char __user *argp;
327 struct fs3270 *fp;
328 struct raw3270_iocb iocb;
329 int rc;
330
331 fp = filp->private_data;
332 if (!fp)
333 return -ENODEV;
334 if (is_compat_task())
335 argp = compat_ptr(arg);
336 else
337 argp = (char __user *)arg;
338 rc = 0;
339 mutex_lock(&fs3270_mutex);
340 switch (cmd) {
341 case TUBICMD:
342 fp->read_command = arg;
343 break;
344 case TUBOCMD:
345 fp->write_command = arg;
346 break;
347 case TUBGETI:
348 rc = put_user(fp->read_command, argp);
349 break;
350 case TUBGETO:
351 rc = put_user(fp->write_command, argp);
352 break;
353 case TUBGETMOD:
354 iocb.model = fp->view.model;
355 iocb.line_cnt = fp->view.rows;
356 iocb.col_cnt = fp->view.cols;
357 iocb.pf_cnt = 24;
358 iocb.re_cnt = 20;
359 iocb.map = 0;
360 if (copy_to_user(argp, &iocb, sizeof(struct raw3270_iocb)))
361 rc = -EFAULT;
362 break;
363 }
364 mutex_unlock(&fs3270_mutex);
365 return rc;
366 }
367
368 /*
369 * Allocate fs3270 structure.
370 */
371 static struct fs3270 *
fs3270_alloc_view(void)372 fs3270_alloc_view(void)
373 {
374 struct fs3270 *fp;
375
376 fp = kzalloc(sizeof(struct fs3270),GFP_KERNEL);
377 if (!fp)
378 return ERR_PTR(-ENOMEM);
379 fp->init = raw3270_request_alloc(0);
380 if (IS_ERR(fp->init)) {
381 kfree(fp);
382 return ERR_PTR(-ENOMEM);
383 }
384 return fp;
385 }
386
387 /*
388 * Free fs3270 structure.
389 */
390 static void
fs3270_free_view(struct raw3270_view * view)391 fs3270_free_view(struct raw3270_view *view)
392 {
393 struct fs3270 *fp;
394
395 fp = (struct fs3270 *) view;
396 if (fp->rdbuf)
397 idal_buffer_free(fp->rdbuf);
398 raw3270_request_free(((struct fs3270 *) view)->init);
399 kfree(view);
400 }
401
402 /*
403 * Unlink fs3270 data structure from filp.
404 */
405 static void
fs3270_release(struct raw3270_view * view)406 fs3270_release(struct raw3270_view *view)
407 {
408 struct fs3270 *fp;
409
410 fp = (struct fs3270 *) view;
411 if (fp->fs_pid)
412 kill_pid(fp->fs_pid, SIGHUP, 1);
413 }
414
415 /* View to a 3270 device. Can be console, tty or fullscreen. */
416 static struct raw3270_fn fs3270_fn = {
417 .activate = fs3270_activate,
418 .deactivate = fs3270_deactivate,
419 .intv = (void *) fs3270_irq,
420 .release = fs3270_release,
421 .free = fs3270_free_view
422 };
423
424 /*
425 * This routine is called whenever a 3270 fullscreen device is opened.
426 */
427 static int
fs3270_open(struct inode * inode,struct file * filp)428 fs3270_open(struct inode *inode, struct file *filp)
429 {
430 struct fs3270 *fp;
431 struct idal_buffer *ib;
432 int minor, rc = 0;
433
434 if (imajor(filp->f_path.dentry->d_inode) != IBM_FS3270_MAJOR)
435 return -ENODEV;
436 minor = iminor(filp->f_path.dentry->d_inode);
437 /* Check for minor 0 multiplexer. */
438 if (minor == 0) {
439 struct tty_struct *tty = get_current_tty();
440 if (!tty || tty->driver->major != IBM_TTY3270_MAJOR) {
441 tty_kref_put(tty);
442 return -ENODEV;
443 }
444 minor = tty->index + RAW3270_FIRSTMINOR;
445 tty_kref_put(tty);
446 }
447 mutex_lock(&fs3270_mutex);
448 /* Check if some other program is already using fullscreen mode. */
449 fp = (struct fs3270 *) raw3270_find_view(&fs3270_fn, minor);
450 if (!IS_ERR(fp)) {
451 raw3270_put_view(&fp->view);
452 rc = -EBUSY;
453 goto out;
454 }
455 /* Allocate fullscreen view structure. */
456 fp = fs3270_alloc_view();
457 if (IS_ERR(fp)) {
458 rc = PTR_ERR(fp);
459 goto out;
460 }
461
462 init_waitqueue_head(&fp->wait);
463 fp->fs_pid = get_pid(task_pid(current));
464 rc = raw3270_add_view(&fp->view, &fs3270_fn, minor);
465 if (rc) {
466 fs3270_free_view(&fp->view);
467 goto out;
468 }
469
470 /* Allocate idal-buffer. */
471 ib = idal_buffer_alloc(2*fp->view.rows*fp->view.cols + 5, 0);
472 if (IS_ERR(ib)) {
473 raw3270_put_view(&fp->view);
474 raw3270_del_view(&fp->view);
475 rc = PTR_ERR(ib);
476 goto out;
477 }
478 fp->rdbuf = ib;
479
480 rc = raw3270_activate_view(&fp->view);
481 if (rc) {
482 raw3270_put_view(&fp->view);
483 raw3270_del_view(&fp->view);
484 goto out;
485 }
486 nonseekable_open(inode, filp);
487 filp->private_data = fp;
488 out:
489 mutex_unlock(&fs3270_mutex);
490 return rc;
491 }
492
493 /*
494 * This routine is called when the 3270 tty is closed. We wait
495 * for the remaining request to be completed. Then we clean up.
496 */
497 static int
fs3270_close(struct inode * inode,struct file * filp)498 fs3270_close(struct inode *inode, struct file *filp)
499 {
500 struct fs3270 *fp;
501
502 fp = filp->private_data;
503 filp->private_data = NULL;
504 if (fp) {
505 put_pid(fp->fs_pid);
506 fp->fs_pid = NULL;
507 raw3270_reset(&fp->view);
508 raw3270_put_view(&fp->view);
509 raw3270_del_view(&fp->view);
510 }
511 return 0;
512 }
513
514 static const struct file_operations fs3270_fops = {
515 .owner = THIS_MODULE, /* owner */
516 .read = fs3270_read, /* read */
517 .write = fs3270_write, /* write */
518 .unlocked_ioctl = fs3270_ioctl, /* ioctl */
519 .compat_ioctl = fs3270_ioctl, /* ioctl */
520 .open = fs3270_open, /* open */
521 .release = fs3270_close, /* release */
522 .llseek = no_llseek,
523 };
524
525 /*
526 * 3270 fullscreen driver initialization.
527 */
528 static int __init
fs3270_init(void)529 fs3270_init(void)
530 {
531 int rc;
532
533 rc = register_chrdev(IBM_FS3270_MAJOR, "fs3270", &fs3270_fops);
534 if (rc)
535 return rc;
536 return 0;
537 }
538
539 static void __exit
fs3270_exit(void)540 fs3270_exit(void)
541 {
542 unregister_chrdev(IBM_FS3270_MAJOR, "fs3270");
543 }
544
545 MODULE_LICENSE("GPL");
546 MODULE_ALIAS_CHARDEV_MAJOR(IBM_FS3270_MAJOR);
547
548 module_init(fs3270_init);
549 module_exit(fs3270_exit);
550