Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost
[cris-mirror.git] / drivers / s390 / char / fs3270.c
blob61822480a2a0bdfa808e4f9d3e19965857e7700d
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * IBM/3270 Driver - fullscreen driver.
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 IBM Corp. 2003, 2009
9 */
11 #include <linux/bootmem.h>
12 #include <linux/console.h>
13 #include <linux/init.h>
14 #include <linux/interrupt.h>
15 #include <linux/compat.h>
16 #include <linux/sched/signal.h>
17 #include <linux/module.h>
18 #include <linux/list.h>
19 #include <linux/slab.h>
20 #include <linux/types.h>
22 #include <asm/compat.h>
23 #include <asm/ccwdev.h>
24 #include <asm/cio.h>
25 #include <asm/ebcdic.h>
26 #include <asm/idals.h>
28 #include "raw3270.h"
29 #include "ctrlchar.h"
31 static struct raw3270_fn fs3270_fn;
33 struct fs3270 {
34 struct raw3270_view view;
35 struct pid *fs_pid; /* Pid of controlling program. */
36 int read_command; /* ccw command to use for reads. */
37 int write_command; /* ccw command to use for writes. */
38 int attention; /* Got attention. */
39 int active; /* Fullscreen view is active. */
40 struct raw3270_request *init; /* single init request. */
41 wait_queue_head_t wait; /* Init & attention wait queue. */
42 struct idal_buffer *rdbuf; /* full-screen-deactivate buffer */
43 size_t rdbuf_size; /* size of data returned by RDBUF */
46 static DEFINE_MUTEX(fs3270_mutex);
48 static void
49 fs3270_wake_up(struct raw3270_request *rq, void *data)
51 wake_up((wait_queue_head_t *) data);
54 static inline int
55 fs3270_working(struct fs3270 *fp)
58 * The fullscreen view is in working order if the view
59 * has been activated AND the initial request is finished.
61 return fp->active && raw3270_request_final(fp->init);
64 static int
65 fs3270_do_io(struct raw3270_view *view, struct raw3270_request *rq)
67 struct fs3270 *fp;
68 int rc;
70 fp = (struct fs3270 *) view;
71 rq->callback = fs3270_wake_up;
72 rq->callback_data = &fp->wait;
74 do {
75 if (!fs3270_working(fp)) {
76 /* Fullscreen view isn't ready yet. */
77 rc = wait_event_interruptible(fp->wait,
78 fs3270_working(fp));
79 if (rc != 0)
80 break;
82 rc = raw3270_start(view, rq);
83 if (rc == 0) {
84 /* Started successfully. Now wait for completion. */
85 wait_event(fp->wait, raw3270_request_final(rq));
87 } while (rc == -EACCES);
88 return rc;
92 * Switch to the fullscreen view.
94 static void
95 fs3270_reset_callback(struct raw3270_request *rq, void *data)
97 struct fs3270 *fp;
99 fp = (struct fs3270 *) rq->view;
100 raw3270_request_reset(rq);
101 wake_up(&fp->wait);
104 static void
105 fs3270_restore_callback(struct raw3270_request *rq, void *data)
107 struct fs3270 *fp;
109 fp = (struct fs3270 *) rq->view;
110 if (rq->rc != 0 || rq->rescnt != 0) {
111 if (fp->fs_pid)
112 kill_pid(fp->fs_pid, SIGHUP, 1);
114 fp->rdbuf_size = 0;
115 raw3270_request_reset(rq);
116 wake_up(&fp->wait);
119 static int
120 fs3270_activate(struct raw3270_view *view)
122 struct fs3270 *fp;
123 char *cp;
124 int rc;
126 fp = (struct fs3270 *) view;
128 /* If an old init command is still running just return. */
129 if (!raw3270_request_final(fp->init))
130 return 0;
132 if (fp->rdbuf_size == 0) {
133 /* No saved buffer. Just clear the screen. */
134 raw3270_request_set_cmd(fp->init, TC_EWRITEA);
135 fp->init->callback = fs3270_reset_callback;
136 } else {
137 /* Restore fullscreen buffer saved by fs3270_deactivate. */
138 raw3270_request_set_cmd(fp->init, TC_EWRITEA);
139 raw3270_request_set_idal(fp->init, fp->rdbuf);
140 fp->init->ccw.count = fp->rdbuf_size;
141 cp = fp->rdbuf->data[0];
142 cp[0] = TW_KR;
143 cp[1] = TO_SBA;
144 cp[2] = cp[6];
145 cp[3] = cp[7];
146 cp[4] = TO_IC;
147 cp[5] = TO_SBA;
148 cp[6] = 0x40;
149 cp[7] = 0x40;
150 fp->init->rescnt = 0;
151 fp->init->callback = fs3270_restore_callback;
153 rc = fp->init->rc = raw3270_start_locked(view, fp->init);
154 if (rc)
155 fp->init->callback(fp->init, NULL);
156 else
157 fp->active = 1;
158 return rc;
162 * Shutdown fullscreen view.
164 static void
165 fs3270_save_callback(struct raw3270_request *rq, void *data)
167 struct fs3270 *fp;
169 fp = (struct fs3270 *) rq->view;
171 /* Correct idal buffer element 0 address. */
172 fp->rdbuf->data[0] -= 5;
173 fp->rdbuf->size += 5;
176 * If the rdbuf command failed or the idal buffer is
177 * to small for the amount of data returned by the
178 * rdbuf command, then we have no choice but to send
179 * a SIGHUP to the application.
181 if (rq->rc != 0 || rq->rescnt == 0) {
182 if (fp->fs_pid)
183 kill_pid(fp->fs_pid, SIGHUP, 1);
184 fp->rdbuf_size = 0;
185 } else
186 fp->rdbuf_size = fp->rdbuf->size - rq->rescnt;
187 raw3270_request_reset(rq);
188 wake_up(&fp->wait);
191 static void
192 fs3270_deactivate(struct raw3270_view *view)
194 struct fs3270 *fp;
196 fp = (struct fs3270 *) view;
197 fp->active = 0;
199 /* If an old init command is still running just return. */
200 if (!raw3270_request_final(fp->init))
201 return;
203 /* Prepare read-buffer request. */
204 raw3270_request_set_cmd(fp->init, TC_RDBUF);
206 * Hackish: skip first 5 bytes of the idal buffer to make
207 * room for the TW_KR/TO_SBA/<address>/<address>/TO_IC sequence
208 * in the activation command.
210 fp->rdbuf->data[0] += 5;
211 fp->rdbuf->size -= 5;
212 raw3270_request_set_idal(fp->init, fp->rdbuf);
213 fp->init->rescnt = 0;
214 fp->init->callback = fs3270_save_callback;
216 /* Start I/O to read in the 3270 buffer. */
217 fp->init->rc = raw3270_start_locked(view, fp->init);
218 if (fp->init->rc)
219 fp->init->callback(fp->init, NULL);
222 static void
223 fs3270_irq(struct fs3270 *fp, struct raw3270_request *rq, struct irb *irb)
225 /* Handle ATTN. Set indication and wake waiters for attention. */
226 if (irb->scsw.cmd.dstat & DEV_STAT_ATTENTION) {
227 fp->attention = 1;
228 wake_up(&fp->wait);
231 if (rq) {
232 if (irb->scsw.cmd.dstat & DEV_STAT_UNIT_CHECK)
233 rq->rc = -EIO;
234 else
235 /* Normal end. Copy residual count. */
236 rq->rescnt = irb->scsw.cmd.count;
241 * Process reads from fullscreen 3270.
243 static ssize_t
244 fs3270_read(struct file *filp, char __user *data, size_t count, loff_t *off)
246 struct fs3270 *fp;
247 struct raw3270_request *rq;
248 struct idal_buffer *ib;
249 ssize_t rc;
251 if (count == 0 || count > 65535)
252 return -EINVAL;
253 fp = filp->private_data;
254 if (!fp)
255 return -ENODEV;
256 ib = idal_buffer_alloc(count, 0);
257 if (IS_ERR(ib))
258 return -ENOMEM;
259 rq = raw3270_request_alloc(0);
260 if (!IS_ERR(rq)) {
261 if (fp->read_command == 0 && fp->write_command != 0)
262 fp->read_command = 6;
263 raw3270_request_set_cmd(rq, fp->read_command ? : 2);
264 raw3270_request_set_idal(rq, ib);
265 rc = wait_event_interruptible(fp->wait, fp->attention);
266 fp->attention = 0;
267 if (rc == 0) {
268 rc = fs3270_do_io(&fp->view, rq);
269 if (rc == 0) {
270 count -= rq->rescnt;
271 if (idal_buffer_to_user(ib, data, count) != 0)
272 rc = -EFAULT;
273 else
274 rc = count;
278 raw3270_request_free(rq);
279 } else
280 rc = PTR_ERR(rq);
281 idal_buffer_free(ib);
282 return rc;
286 * Process writes to fullscreen 3270.
288 static ssize_t
289 fs3270_write(struct file *filp, const char __user *data, size_t count, loff_t *off)
291 struct fs3270 *fp;
292 struct raw3270_request *rq;
293 struct idal_buffer *ib;
294 int write_command;
295 ssize_t rc;
297 fp = filp->private_data;
298 if (!fp)
299 return -ENODEV;
300 ib = idal_buffer_alloc(count, 0);
301 if (IS_ERR(ib))
302 return -ENOMEM;
303 rq = raw3270_request_alloc(0);
304 if (!IS_ERR(rq)) {
305 if (idal_buffer_from_user(ib, data, count) == 0) {
306 write_command = fp->write_command ? : 1;
307 if (write_command == 5)
308 write_command = 13;
309 raw3270_request_set_cmd(rq, write_command);
310 raw3270_request_set_idal(rq, ib);
311 rc = fs3270_do_io(&fp->view, rq);
312 if (rc == 0)
313 rc = count - rq->rescnt;
314 } else
315 rc = -EFAULT;
316 raw3270_request_free(rq);
317 } else
318 rc = PTR_ERR(rq);
319 idal_buffer_free(ib);
320 return rc;
324 * process ioctl commands for the tube driver
326 static long
327 fs3270_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
329 char __user *argp;
330 struct fs3270 *fp;
331 struct raw3270_iocb iocb;
332 int rc;
334 fp = filp->private_data;
335 if (!fp)
336 return -ENODEV;
337 if (is_compat_task())
338 argp = compat_ptr(arg);
339 else
340 argp = (char __user *)arg;
341 rc = 0;
342 mutex_lock(&fs3270_mutex);
343 switch (cmd) {
344 case TUBICMD:
345 fp->read_command = arg;
346 break;
347 case TUBOCMD:
348 fp->write_command = arg;
349 break;
350 case TUBGETI:
351 rc = put_user(fp->read_command, argp);
352 break;
353 case TUBGETO:
354 rc = put_user(fp->write_command, argp);
355 break;
356 case TUBGETMOD:
357 iocb.model = fp->view.model;
358 iocb.line_cnt = fp->view.rows;
359 iocb.col_cnt = fp->view.cols;
360 iocb.pf_cnt = 24;
361 iocb.re_cnt = 20;
362 iocb.map = 0;
363 if (copy_to_user(argp, &iocb, sizeof(struct raw3270_iocb)))
364 rc = -EFAULT;
365 break;
367 mutex_unlock(&fs3270_mutex);
368 return rc;
372 * Allocate fs3270 structure.
374 static struct fs3270 *
375 fs3270_alloc_view(void)
377 struct fs3270 *fp;
379 fp = kzalloc(sizeof(struct fs3270),GFP_KERNEL);
380 if (!fp)
381 return ERR_PTR(-ENOMEM);
382 fp->init = raw3270_request_alloc(0);
383 if (IS_ERR(fp->init)) {
384 kfree(fp);
385 return ERR_PTR(-ENOMEM);
387 return fp;
391 * Free fs3270 structure.
393 static void
394 fs3270_free_view(struct raw3270_view *view)
396 struct fs3270 *fp;
398 fp = (struct fs3270 *) view;
399 if (fp->rdbuf)
400 idal_buffer_free(fp->rdbuf);
401 raw3270_request_free(((struct fs3270 *) view)->init);
402 kfree(view);
406 * Unlink fs3270 data structure from filp.
408 static void
409 fs3270_release(struct raw3270_view *view)
411 struct fs3270 *fp;
413 fp = (struct fs3270 *) view;
414 if (fp->fs_pid)
415 kill_pid(fp->fs_pid, SIGHUP, 1);
418 /* View to a 3270 device. Can be console, tty or fullscreen. */
419 static struct raw3270_fn fs3270_fn = {
420 .activate = fs3270_activate,
421 .deactivate = fs3270_deactivate,
422 .intv = (void *) fs3270_irq,
423 .release = fs3270_release,
424 .free = fs3270_free_view
428 * This routine is called whenever a 3270 fullscreen device is opened.
430 static int
431 fs3270_open(struct inode *inode, struct file *filp)
433 struct fs3270 *fp;
434 struct idal_buffer *ib;
435 int minor, rc = 0;
437 if (imajor(file_inode(filp)) != IBM_FS3270_MAJOR)
438 return -ENODEV;
439 minor = iminor(file_inode(filp));
440 /* Check for minor 0 multiplexer. */
441 if (minor == 0) {
442 struct tty_struct *tty = get_current_tty();
443 if (!tty || tty->driver->major != IBM_TTY3270_MAJOR) {
444 tty_kref_put(tty);
445 return -ENODEV;
447 minor = tty->index;
448 tty_kref_put(tty);
450 mutex_lock(&fs3270_mutex);
451 /* Check if some other program is already using fullscreen mode. */
452 fp = (struct fs3270 *) raw3270_find_view(&fs3270_fn, minor);
453 if (!IS_ERR(fp)) {
454 raw3270_put_view(&fp->view);
455 rc = -EBUSY;
456 goto out;
458 /* Allocate fullscreen view structure. */
459 fp = fs3270_alloc_view();
460 if (IS_ERR(fp)) {
461 rc = PTR_ERR(fp);
462 goto out;
465 init_waitqueue_head(&fp->wait);
466 fp->fs_pid = get_pid(task_pid(current));
467 rc = raw3270_add_view(&fp->view, &fs3270_fn, minor);
468 if (rc) {
469 fs3270_free_view(&fp->view);
470 goto out;
473 /* Allocate idal-buffer. */
474 ib = idal_buffer_alloc(2*fp->view.rows*fp->view.cols + 5, 0);
475 if (IS_ERR(ib)) {
476 raw3270_put_view(&fp->view);
477 raw3270_del_view(&fp->view);
478 rc = PTR_ERR(ib);
479 goto out;
481 fp->rdbuf = ib;
483 rc = raw3270_activate_view(&fp->view);
484 if (rc) {
485 raw3270_put_view(&fp->view);
486 raw3270_del_view(&fp->view);
487 goto out;
489 nonseekable_open(inode, filp);
490 filp->private_data = fp;
491 out:
492 mutex_unlock(&fs3270_mutex);
493 return rc;
497 * This routine is called when the 3270 tty is closed. We wait
498 * for the remaining request to be completed. Then we clean up.
500 static int
501 fs3270_close(struct inode *inode, struct file *filp)
503 struct fs3270 *fp;
505 fp = filp->private_data;
506 filp->private_data = NULL;
507 if (fp) {
508 put_pid(fp->fs_pid);
509 fp->fs_pid = NULL;
510 raw3270_reset(&fp->view);
511 raw3270_put_view(&fp->view);
512 raw3270_del_view(&fp->view);
514 return 0;
517 static const struct file_operations fs3270_fops = {
518 .owner = THIS_MODULE, /* owner */
519 .read = fs3270_read, /* read */
520 .write = fs3270_write, /* write */
521 .unlocked_ioctl = fs3270_ioctl, /* ioctl */
522 .compat_ioctl = fs3270_ioctl, /* ioctl */
523 .open = fs3270_open, /* open */
524 .release = fs3270_close, /* release */
525 .llseek = no_llseek,
528 static void fs3270_create_cb(int minor)
530 __register_chrdev(IBM_FS3270_MAJOR, minor, 1, "tub", &fs3270_fops);
531 device_create(class3270, NULL, MKDEV(IBM_FS3270_MAJOR, minor),
532 NULL, "3270/tub%d", minor);
535 static void fs3270_destroy_cb(int minor)
537 device_destroy(class3270, MKDEV(IBM_FS3270_MAJOR, minor));
538 __unregister_chrdev(IBM_FS3270_MAJOR, minor, 1, "tub");
541 static struct raw3270_notifier fs3270_notifier =
543 .create = fs3270_create_cb,
544 .destroy = fs3270_destroy_cb,
548 * 3270 fullscreen driver initialization.
550 static int __init
551 fs3270_init(void)
553 int rc;
555 rc = __register_chrdev(IBM_FS3270_MAJOR, 0, 1, "fs3270", &fs3270_fops);
556 if (rc)
557 return rc;
558 device_create(class3270, NULL, MKDEV(IBM_FS3270_MAJOR, 0),
559 NULL, "3270/tub");
560 raw3270_register_notifier(&fs3270_notifier);
561 return 0;
564 static void __exit
565 fs3270_exit(void)
567 raw3270_unregister_notifier(&fs3270_notifier);
568 device_destroy(class3270, MKDEV(IBM_FS3270_MAJOR, 0));
569 __unregister_chrdev(IBM_FS3270_MAJOR, 0, 1, "fs3270");
572 MODULE_LICENSE("GPL");
573 MODULE_ALIAS_CHARDEV_MAJOR(IBM_FS3270_MAJOR);
575 module_init(fs3270_init);
576 module_exit(fs3270_exit);