xref: /openbmc/linux/drivers/s390/char/fs3270.c (revision 1da177e4)
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 	struct raw3270_request *clear;	/* single clear request. */
37 	wait_queue_head_t attn_wait;	/* Attention wait queue. */
38 };
39 
40 static void
41 fs3270_wake_up(struct raw3270_request *rq, void *data)
42 {
43 	wake_up((wait_queue_head_t *) data);
44 }
45 
46 static int
47 fs3270_do_io(struct raw3270_view *view, struct raw3270_request *rq)
48 {
49 	wait_queue_head_t wq;
50 	int rc;
51 
52 	init_waitqueue_head(&wq);
53 	rq->callback = fs3270_wake_up;
54 	rq->callback_data = &wq;
55 	rc = raw3270_start(view, rq);
56 	if (rc)
57 		return rc;
58 	/* Started sucessfully. Now wait for completion. */
59 	wait_event(wq, raw3270_request_final(rq));
60 	return rq->rc;
61 }
62 
63 static void
64 fs3270_reset_callback(struct raw3270_request *rq, void *data)
65 {
66 	raw3270_request_reset(rq);
67 }
68 
69 /*
70  * Switch to the fullscreen view.
71  */
72 static int
73 fs3270_activate(struct raw3270_view *view)
74 {
75 	struct fs3270 *fp;
76 
77 	fp = (struct fs3270 *) view;
78 	raw3270_request_set_cmd(fp->clear, TC_EWRITEA);
79 	fp->clear->callback = fs3270_reset_callback;
80 	return raw3270_start(view, fp->clear);
81 }
82 
83 /*
84  * Shutdown fullscreen view.
85  */
86 static void
87 fs3270_deactivate(struct raw3270_view *view)
88 {
89 	// FIXME: is this a good idea? The user program using fullscreen 3270
90 	// will die just because a console message appeared. On the other
91 	// hand the fullscreen device is unoperational now.
92 	struct fs3270 *fp;
93 
94 	fp = (struct fs3270 *) view;
95 	if (fp->fs_pid != 0)
96 		kill_proc(fp->fs_pid, SIGHUP, 1);
97 	fp->fs_pid = 0;
98 }
99 
100 static int
101 fs3270_irq(struct fs3270 *fp, struct raw3270_request *rq, struct irb *irb)
102 {
103 	/* Handle ATTN. Set indication and wake waiters for attention. */
104 	if (irb->scsw.dstat & DEV_STAT_ATTENTION) {
105 		fp->attention = 1;
106 		wake_up(&fp->attn_wait);
107 	}
108 
109 	if (rq) {
110 		if (irb->scsw.dstat & DEV_STAT_UNIT_CHECK)
111 			rq->rc = -EIO;
112 		else
113 			/* Normal end. Copy residual count. */
114 			rq->rescnt = irb->scsw.count;
115 	}
116 	return RAW3270_IO_DONE;
117 }
118 
119 /*
120  * Process reads from fullscreen 3270.
121  */
122 static ssize_t
123 fs3270_read(struct file *filp, char *data, size_t count, loff_t *off)
124 {
125 	struct fs3270 *fp;
126 	struct raw3270_request *rq;
127 	struct idal_buffer *ib;
128 	int rc;
129 
130 	if (count == 0 || count > 65535)
131 		return -EINVAL;
132 	fp = filp->private_data;
133 	if (!fp)
134 		return -ENODEV;
135 	ib = idal_buffer_alloc(count, 0);
136 	if (!ib)
137 		return -ENOMEM;
138 	rq = raw3270_request_alloc(0);
139 	if (!IS_ERR(rq)) {
140 		if (fp->read_command == 0 && fp->write_command != 0)
141 			fp->read_command = 6;
142 		raw3270_request_set_cmd(rq, fp->read_command ? : 2);
143 		raw3270_request_set_idal(rq, ib);
144 		wait_event(fp->attn_wait, fp->attention);
145 		rc = fs3270_do_io(&fp->view, rq);
146 		if (rc == 0 && idal_buffer_to_user(ib, data, count))
147 			rc = -EFAULT;
148 		raw3270_request_free(rq);
149 	} else
150 		rc = PTR_ERR(rq);
151 	idal_buffer_free(ib);
152 	return rc;
153 }
154 
155 /*
156  * Process writes to fullscreen 3270.
157  */
158 static ssize_t
159 fs3270_write(struct file *filp, const char *data, size_t count, loff_t *off)
160 {
161 	struct fs3270 *fp;
162 	struct raw3270_request *rq;
163 	struct idal_buffer *ib;
164 	int write_command;
165 	int rc;
166 
167 	fp = filp->private_data;
168 	if (!fp)
169 		return -ENODEV;
170 	ib = idal_buffer_alloc(count, 0);
171 	if (!ib)
172 		return -ENOMEM;
173 	rq = raw3270_request_alloc(0);
174 	if (!IS_ERR(rq)) {
175 		if (idal_buffer_from_user(ib, data, count) == 0) {
176 			write_command = fp->write_command ? : 1;
177 			if (write_command == 5)
178 				write_command = 13;
179 			raw3270_request_set_cmd(rq, write_command);
180 			raw3270_request_set_idal(rq, ib);
181 			rc = fs3270_do_io(&fp->view, rq);
182 		} else
183 			rc = -EFAULT;
184 		raw3270_request_free(rq);
185 	} else
186 		rc = PTR_ERR(rq);
187 	idal_buffer_free(ib);
188 	return rc;
189 }
190 
191 /*
192  * process ioctl commands for the tube driver
193  */
194 static int
195 fs3270_ioctl(struct inode *inode, struct file *filp,
196 	     unsigned int cmd, unsigned long arg)
197 {
198 	struct fs3270 *fp;
199 	struct raw3270_iocb iocb;
200 	int rc;
201 
202 	fp = filp->private_data;
203 	if (!fp)
204 		return -ENODEV;
205 	rc = 0;
206 	switch (cmd) {
207 	case TUBICMD:
208 		fp->read_command = arg;
209 		break;
210 	case TUBOCMD:
211 		fp->write_command = arg;
212 		break;
213 	case TUBGETI:
214 		rc = put_user(fp->read_command, (char *) arg);
215 		break;
216 	case TUBGETO:
217 		rc = put_user(fp->write_command,(char *) arg);
218 		break;
219 	case TUBGETMOD:
220 		iocb.model = fp->view.model;
221 		iocb.line_cnt = fp->view.rows;
222 		iocb.col_cnt = fp->view.cols;
223 		iocb.pf_cnt = 24;
224 		iocb.re_cnt = 20;
225 		iocb.map = 0;
226 		if (copy_to_user((char *) arg, &iocb,
227 				 sizeof(struct raw3270_iocb)))
228 			rc = -EFAULT;
229 		break;
230 	}
231 	return rc;
232 }
233 
234 /*
235  * Allocate tty3270 structure.
236  */
237 static struct fs3270 *
238 fs3270_alloc_view(void)
239 {
240 	struct fs3270 *fp;
241 
242 	fp = (struct fs3270 *) kmalloc(sizeof(struct fs3270),GFP_KERNEL);
243 	if (!fp)
244 		return ERR_PTR(-ENOMEM);
245 	memset(fp, 0, sizeof(struct fs3270));
246 	fp->clear = raw3270_request_alloc(0);
247 	if (!IS_ERR(fp->clear)) {
248 		kfree(fp);
249 		return ERR_PTR(-ENOMEM);
250 	}
251 	return fp;
252 }
253 
254 /*
255  * Free tty3270 structure.
256  */
257 static void
258 fs3270_free_view(struct raw3270_view *view)
259 {
260 	raw3270_request_free(((struct fs3270 *) view)->clear);
261 	kfree(view);
262 }
263 
264 /*
265  * Unlink fs3270 data structure from filp.
266  */
267 static void
268 fs3270_release(struct raw3270_view *view)
269 {
270 }
271 
272 /* View to a 3270 device. Can be console, tty or fullscreen. */
273 struct raw3270_fn fs3270_fn = {
274 	.activate = fs3270_activate,
275 	.deactivate = fs3270_deactivate,
276 	.intv = (void *) fs3270_irq,
277 	.release = fs3270_release,
278 	.free = fs3270_free_view
279 };
280 
281 /*
282  * This routine is called whenever a 3270 fullscreen device is opened.
283  */
284 static int
285 fs3270_open(struct inode *inode, struct file *filp)
286 {
287 	struct fs3270 *fp;
288 	int minor, rc;
289 
290 	if (imajor(filp->f_dentry->d_inode) != IBM_FS3270_MAJOR)
291 		return -ENODEV;
292 	minor = iminor(filp->f_dentry->d_inode);
293 	/* Check if some other program is already using fullscreen mode. */
294 	fp = (struct fs3270 *) raw3270_find_view(&fs3270_fn, minor);
295 	if (!IS_ERR(fp)) {
296 		raw3270_put_view(&fp->view);
297 		return -EBUSY;
298 	}
299 	/* Allocate fullscreen view structure. */
300 	fp = fs3270_alloc_view();
301 	if (IS_ERR(fp))
302 		return PTR_ERR(fp);
303 
304 	init_waitqueue_head(&fp->attn_wait);
305 	fp->fs_pid = current->pid;
306 	rc = raw3270_add_view(&fp->view, &fs3270_fn, minor);
307 	if (rc) {
308 		fs3270_free_view(&fp->view);
309 		return rc;
310 	}
311 
312 	rc = raw3270_activate_view(&fp->view);
313 	if (rc) {
314 		raw3270_del_view(&fp->view);
315 		return rc;
316 	}
317 	filp->private_data = fp;
318 	return 0;
319 }
320 
321 /*
322  * This routine is called when the 3270 tty is closed. We wait
323  * for the remaining request to be completed. Then we clean up.
324  */
325 static int
326 fs3270_close(struct inode *inode, struct file *filp)
327 {
328 	struct fs3270 *fp;
329 
330 	fp = filp->private_data;
331 	filp->private_data = 0;
332 	if (fp)
333 		raw3270_del_view(&fp->view);
334 	return 0;
335 }
336 
337 static struct file_operations fs3270_fops = {
338 	.owner	 = THIS_MODULE,		/* owner */
339 	.read	 = fs3270_read,		/* read */
340 	.write	 = fs3270_write,	/* write */
341 	.ioctl	 = fs3270_ioctl,	/* ioctl */
342 	.open	 = fs3270_open,		/* open */
343 	.release = fs3270_close,	/* release */
344 };
345 
346 /*
347  * 3270 fullscreen driver initialization.
348  */
349 static int __init
350 fs3270_init(void)
351 {
352 	int rc;
353 
354 	rc = register_chrdev(IBM_FS3270_MAJOR, "fs3270", &fs3270_fops);
355 	if (rc) {
356 		printk(KERN_ERR "fs3270 can't get major number %d: errno %d\n",
357 		       IBM_FS3270_MAJOR, rc);
358 		return rc;
359 	}
360 	return 0;
361 }
362 
363 static void __exit
364 fs3270_exit(void)
365 {
366 	unregister_chrdev(IBM_FS3270_MAJOR, "fs3270");
367 }
368 
369 MODULE_LICENSE("GPL");
370 MODULE_ALIAS_CHARDEV_MAJOR(IBM_FS3270_MAJOR);
371 
372 module_init(fs3270_init);
373 module_exit(fs3270_exit);
374