1 // SPDX-License-Identifier: GPL-2.0 2 /* 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 IBM Corp. 2003, 2009 9 */ 10 11 #include <linux/memblock.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> 21 22 #include <asm/ccwdev.h> 23 #include <asm/cio.h> 24 #include <asm/ebcdic.h> 25 #include <asm/idals.h> 26 27 #include "raw3270.h" 28 #include "ctrlchar.h" 29 30 static struct raw3270_fn fs3270_fn; 31 32 struct fs3270 { 33 struct raw3270_view view; 34 struct pid *fs_pid; /* Pid of controlling program. */ 35 int read_command; /* ccw command to use for reads. */ 36 int write_command; /* ccw command to use for writes. */ 37 int attention; /* Got attention. */ 38 int active; /* Fullscreen view is active. */ 39 struct raw3270_request *init; /* single init request. */ 40 wait_queue_head_t wait; /* Init & attention wait queue. */ 41 struct idal_buffer *rdbuf; /* full-screen-deactivate buffer */ 42 size_t rdbuf_size; /* size of data returned by RDBUF */ 43 }; 44 45 static DEFINE_MUTEX(fs3270_mutex); 46 47 static void 48 fs3270_wake_up(struct raw3270_request *rq, void *data) 49 { 50 wake_up((wait_queue_head_t *) data); 51 } 52 53 static inline int 54 fs3270_working(struct fs3270 *fp) 55 { 56 /* 57 * The fullscreen view is in working order if the view 58 * has been activated AND the initial request is finished. 59 */ 60 return fp->active && raw3270_request_final(fp->init); 61 } 62 63 static int 64 fs3270_do_io(struct raw3270_view *view, struct raw3270_request *rq) 65 { 66 struct fs3270 *fp; 67 int rc; 68 69 fp = (struct fs3270 *) view; 70 rq->callback = fs3270_wake_up; 71 rq->callback_data = &fp->wait; 72 73 do { 74 if (!fs3270_working(fp)) { 75 /* Fullscreen view isn't ready yet. */ 76 rc = wait_event_interruptible(fp->wait, 77 fs3270_working(fp)); 78 if (rc != 0) 79 break; 80 } 81 rc = raw3270_start(view, rq); 82 if (rc == 0) { 83 /* Started successfully. Now wait for completion. */ 84 wait_event(fp->wait, raw3270_request_final(rq)); 85 } 86 } while (rc == -EACCES); 87 return rc; 88 } 89 90 /* 91 * Switch to the fullscreen view. 92 */ 93 static void 94 fs3270_reset_callback(struct raw3270_request *rq, void *data) 95 { 96 struct fs3270 *fp; 97 98 fp = (struct fs3270 *) rq->view; 99 raw3270_request_reset(rq); 100 wake_up(&fp->wait); 101 } 102 103 static void 104 fs3270_restore_callback(struct raw3270_request *rq, void *data) 105 { 106 struct fs3270 *fp; 107 108 fp = (struct fs3270 *) rq->view; 109 if (rq->rc != 0 || rq->rescnt != 0) { 110 if (fp->fs_pid) 111 kill_pid(fp->fs_pid, SIGHUP, 1); 112 } 113 fp->rdbuf_size = 0; 114 raw3270_request_reset(rq); 115 wake_up(&fp->wait); 116 } 117 118 static int 119 fs3270_activate(struct raw3270_view *view) 120 { 121 struct fs3270 *fp; 122 char *cp; 123 int rc; 124 125 fp = (struct fs3270 *) view; 126 127 /* If an old init command is still running just return. */ 128 if (!raw3270_request_final(fp->init)) 129 return 0; 130 131 if (fp->rdbuf_size == 0) { 132 /* No saved buffer. Just clear the screen. */ 133 raw3270_request_set_cmd(fp->init, TC_EWRITEA); 134 fp->init->callback = fs3270_reset_callback; 135 } else { 136 /* Restore fullscreen buffer saved by fs3270_deactivate. */ 137 raw3270_request_set_cmd(fp->init, TC_EWRITEA); 138 raw3270_request_set_idal(fp->init, fp->rdbuf); 139 fp->init->ccw.count = fp->rdbuf_size; 140 cp = fp->rdbuf->data[0]; 141 cp[0] = TW_KR; 142 cp[1] = TO_SBA; 143 cp[2] = cp[6]; 144 cp[3] = cp[7]; 145 cp[4] = TO_IC; 146 cp[5] = TO_SBA; 147 cp[6] = 0x40; 148 cp[7] = 0x40; 149 fp->init->rescnt = 0; 150 fp->init->callback = fs3270_restore_callback; 151 } 152 rc = fp->init->rc = raw3270_start_locked(view, fp->init); 153 if (rc) 154 fp->init->callback(fp->init, NULL); 155 else 156 fp->active = 1; 157 return rc; 158 } 159 160 /* 161 * Shutdown fullscreen view. 162 */ 163 static void 164 fs3270_save_callback(struct raw3270_request *rq, void *data) 165 { 166 struct fs3270 *fp; 167 168 fp = (struct fs3270 *) rq->view; 169 170 /* Correct idal buffer element 0 address. */ 171 fp->rdbuf->data[0] -= 5; 172 fp->rdbuf->size += 5; 173 174 /* 175 * If the rdbuf command failed or the idal buffer is 176 * to small for the amount of data returned by the 177 * rdbuf command, then we have no choice but to send 178 * a SIGHUP to the application. 179 */ 180 if (rq->rc != 0 || rq->rescnt == 0) { 181 if (fp->fs_pid) 182 kill_pid(fp->fs_pid, SIGHUP, 1); 183 fp->rdbuf_size = 0; 184 } else 185 fp->rdbuf_size = fp->rdbuf->size - rq->rescnt; 186 raw3270_request_reset(rq); 187 wake_up(&fp->wait); 188 } 189 190 static void 191 fs3270_deactivate(struct raw3270_view *view) 192 { 193 struct fs3270 *fp; 194 195 fp = (struct fs3270 *) view; 196 fp->active = 0; 197 198 /* If an old init command is still running just return. */ 199 if (!raw3270_request_final(fp->init)) 200 return; 201 202 /* Prepare read-buffer request. */ 203 raw3270_request_set_cmd(fp->init, TC_RDBUF); 204 /* 205 * Hackish: skip first 5 bytes of the idal buffer to make 206 * room for the TW_KR/TO_SBA/<address>/<address>/TO_IC sequence 207 * in the activation command. 208 */ 209 fp->rdbuf->data[0] += 5; 210 fp->rdbuf->size -= 5; 211 raw3270_request_set_idal(fp->init, fp->rdbuf); 212 fp->init->rescnt = 0; 213 fp->init->callback = fs3270_save_callback; 214 215 /* Start I/O to read in the 3270 buffer. */ 216 fp->init->rc = raw3270_start_locked(view, fp->init); 217 if (fp->init->rc) 218 fp->init->callback(fp->init, NULL); 219 } 220 221 static void 222 fs3270_irq(struct fs3270 *fp, struct raw3270_request *rq, struct irb *irb) 223 { 224 /* Handle ATTN. Set indication and wake waiters for attention. */ 225 if (irb->scsw.cmd.dstat & DEV_STAT_ATTENTION) { 226 fp->attention = 1; 227 wake_up(&fp->wait); 228 } 229 230 if (rq) { 231 if (irb->scsw.cmd.dstat & DEV_STAT_UNIT_CHECK) 232 rq->rc = -EIO; 233 else 234 /* Normal end. Copy residual count. */ 235 rq->rescnt = irb->scsw.cmd.count; 236 } 237 } 238 239 /* 240 * Process reads from fullscreen 3270. 241 */ 242 static ssize_t 243 fs3270_read(struct file *filp, char __user *data, size_t count, loff_t *off) 244 { 245 struct fs3270 *fp; 246 struct raw3270_request *rq; 247 struct idal_buffer *ib; 248 ssize_t rc; 249 250 if (count == 0 || count > 65535) 251 return -EINVAL; 252 fp = filp->private_data; 253 if (!fp) 254 return -ENODEV; 255 ib = idal_buffer_alloc(count, 0); 256 if (IS_ERR(ib)) 257 return -ENOMEM; 258 rq = raw3270_request_alloc(0); 259 if (!IS_ERR(rq)) { 260 if (fp->read_command == 0 && fp->write_command != 0) 261 fp->read_command = 6; 262 raw3270_request_set_cmd(rq, fp->read_command ? : 2); 263 raw3270_request_set_idal(rq, ib); 264 rc = wait_event_interruptible(fp->wait, fp->attention); 265 fp->attention = 0; 266 if (rc == 0) { 267 rc = fs3270_do_io(&fp->view, rq); 268 if (rc == 0) { 269 count -= rq->rescnt; 270 if (idal_buffer_to_user(ib, data, count) != 0) 271 rc = -EFAULT; 272 else 273 rc = count; 274 275 } 276 } 277 raw3270_request_free(rq); 278 } else 279 rc = PTR_ERR(rq); 280 idal_buffer_free(ib); 281 return rc; 282 } 283 284 /* 285 * Process writes to fullscreen 3270. 286 */ 287 static ssize_t 288 fs3270_write(struct file *filp, const char __user *data, size_t count, loff_t *off) 289 { 290 struct fs3270 *fp; 291 struct raw3270_request *rq; 292 struct idal_buffer *ib; 293 int write_command; 294 ssize_t rc; 295 296 fp = filp->private_data; 297 if (!fp) 298 return -ENODEV; 299 ib = idal_buffer_alloc(count, 0); 300 if (IS_ERR(ib)) 301 return -ENOMEM; 302 rq = raw3270_request_alloc(0); 303 if (!IS_ERR(rq)) { 304 if (idal_buffer_from_user(ib, data, count) == 0) { 305 write_command = fp->write_command ? : 1; 306 if (write_command == 5) 307 write_command = 13; 308 raw3270_request_set_cmd(rq, write_command); 309 raw3270_request_set_idal(rq, ib); 310 rc = fs3270_do_io(&fp->view, rq); 311 if (rc == 0) 312 rc = count - rq->rescnt; 313 } else 314 rc = -EFAULT; 315 raw3270_request_free(rq); 316 } else 317 rc = PTR_ERR(rq); 318 idal_buffer_free(ib); 319 return rc; 320 } 321 322 /* 323 * process ioctl commands for the tube driver 324 */ 325 static long 326 fs3270_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) 327 { 328 char __user *argp; 329 struct fs3270 *fp; 330 struct raw3270_iocb iocb; 331 int rc; 332 333 fp = filp->private_data; 334 if (!fp) 335 return -ENODEV; 336 if (is_compat_task()) 337 argp = compat_ptr(arg); 338 else 339 argp = (char __user *)arg; 340 rc = 0; 341 mutex_lock(&fs3270_mutex); 342 switch (cmd) { 343 case TUBICMD: 344 fp->read_command = arg; 345 break; 346 case TUBOCMD: 347 fp->write_command = arg; 348 break; 349 case TUBGETI: 350 rc = put_user(fp->read_command, argp); 351 break; 352 case TUBGETO: 353 rc = put_user(fp->write_command, argp); 354 break; 355 case TUBGETMOD: 356 iocb.model = fp->view.model; 357 iocb.line_cnt = fp->view.rows; 358 iocb.col_cnt = fp->view.cols; 359 iocb.pf_cnt = 24; 360 iocb.re_cnt = 20; 361 iocb.map = 0; 362 if (copy_to_user(argp, &iocb, sizeof(struct raw3270_iocb))) 363 rc = -EFAULT; 364 break; 365 } 366 mutex_unlock(&fs3270_mutex); 367 return rc; 368 } 369 370 /* 371 * Allocate fs3270 structure. 372 */ 373 static struct fs3270 * 374 fs3270_alloc_view(void) 375 { 376 struct fs3270 *fp; 377 378 fp = kzalloc(sizeof(struct fs3270),GFP_KERNEL); 379 if (!fp) 380 return ERR_PTR(-ENOMEM); 381 fp->init = raw3270_request_alloc(0); 382 if (IS_ERR(fp->init)) { 383 kfree(fp); 384 return ERR_PTR(-ENOMEM); 385 } 386 return fp; 387 } 388 389 /* 390 * Free fs3270 structure. 391 */ 392 static void 393 fs3270_free_view(struct raw3270_view *view) 394 { 395 struct fs3270 *fp; 396 397 fp = (struct fs3270 *) view; 398 if (fp->rdbuf) 399 idal_buffer_free(fp->rdbuf); 400 raw3270_request_free(((struct fs3270 *) view)->init); 401 kfree(view); 402 } 403 404 /* 405 * Unlink fs3270 data structure from filp. 406 */ 407 static void 408 fs3270_release(struct raw3270_view *view) 409 { 410 struct fs3270 *fp; 411 412 fp = (struct fs3270 *) view; 413 if (fp->fs_pid) 414 kill_pid(fp->fs_pid, SIGHUP, 1); 415 } 416 417 /* View to a 3270 device. Can be console, tty or fullscreen. */ 418 static struct raw3270_fn fs3270_fn = { 419 .activate = fs3270_activate, 420 .deactivate = fs3270_deactivate, 421 .intv = (void *) fs3270_irq, 422 .release = fs3270_release, 423 .free = fs3270_free_view 424 }; 425 426 /* 427 * This routine is called whenever a 3270 fullscreen device is opened. 428 */ 429 static int 430 fs3270_open(struct inode *inode, struct file *filp) 431 { 432 struct fs3270 *fp; 433 struct idal_buffer *ib; 434 int minor, rc = 0; 435 436 if (imajor(file_inode(filp)) != IBM_FS3270_MAJOR) 437 return -ENODEV; 438 minor = iminor(file_inode(filp)); 439 /* Check for minor 0 multiplexer. */ 440 if (minor == 0) { 441 struct tty_struct *tty = get_current_tty(); 442 if (!tty || tty->driver->major != IBM_TTY3270_MAJOR) { 443 tty_kref_put(tty); 444 return -ENODEV; 445 } 446 minor = tty->index; 447 tty_kref_put(tty); 448 } 449 mutex_lock(&fs3270_mutex); 450 /* Check if some other program is already using fullscreen mode. */ 451 fp = (struct fs3270 *) raw3270_find_view(&fs3270_fn, minor); 452 if (!IS_ERR(fp)) { 453 raw3270_put_view(&fp->view); 454 rc = -EBUSY; 455 goto out; 456 } 457 /* Allocate fullscreen view structure. */ 458 fp = fs3270_alloc_view(); 459 if (IS_ERR(fp)) { 460 rc = PTR_ERR(fp); 461 goto out; 462 } 463 464 init_waitqueue_head(&fp->wait); 465 fp->fs_pid = get_pid(task_pid(current)); 466 rc = raw3270_add_view(&fp->view, &fs3270_fn, minor, 467 RAW3270_VIEW_LOCK_BH); 468 if (rc) { 469 fs3270_free_view(&fp->view); 470 goto out; 471 } 472 473 /* 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; 480 } 481 fp->rdbuf = ib; 482 483 rc = raw3270_activate_view(&fp->view); 484 if (rc) { 485 raw3270_put_view(&fp->view); 486 raw3270_del_view(&fp->view); 487 goto out; 488 } 489 stream_open(inode, filp); 490 filp->private_data = fp; 491 out: 492 mutex_unlock(&fs3270_mutex); 493 return rc; 494 } 495 496 /* 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. 499 */ 500 static int 501 fs3270_close(struct inode *inode, struct file *filp) 502 { 503 struct fs3270 *fp; 504 505 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); 513 } 514 return 0; 515 } 516 517 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, 526 }; 527 528 static void fs3270_create_cb(int minor) 529 { 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); 533 } 534 535 static void fs3270_destroy_cb(int minor) 536 { 537 device_destroy(class3270, MKDEV(IBM_FS3270_MAJOR, minor)); 538 __unregister_chrdev(IBM_FS3270_MAJOR, minor, 1, "tub"); 539 } 540 541 static struct raw3270_notifier fs3270_notifier = 542 { 543 .create = fs3270_create_cb, 544 .destroy = fs3270_destroy_cb, 545 }; 546 547 /* 548 * 3270 fullscreen driver initialization. 549 */ 550 static int __init 551 fs3270_init(void) 552 { 553 int rc; 554 555 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; 562 } 563 564 static void __exit 565 fs3270_exit(void) 566 { 567 raw3270_unregister_notifier(&fs3270_notifier); 568 device_destroy(class3270, MKDEV(IBM_FS3270_MAJOR, 0)); 569 __unregister_chrdev(IBM_FS3270_MAJOR, 0, 1, "fs3270"); 570 } 571 572 MODULE_LICENSE("GPL"); 573 MODULE_ALIAS_CHARDEV_MAJOR(IBM_FS3270_MAJOR); 574 575 module_init(fs3270_init); 576 module_exit(fs3270_exit); 577