drivers/s390/char/fs3270.c

   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);