567 lines · c
1// SPDX-License-Identifier: GPL-2.02/*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, 20099 */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 <uapi/asm/fs3270.h>23#include <asm/ccwdev.h>24#include <asm/cio.h>25#include <asm/ebcdic.h>26#include <asm/idals.h>27 28#include "raw3270.h"29#include "ctrlchar.h"30 31static struct raw3270_fn fs3270_fn;32 33struct 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 */44};45 46static DEFINE_MUTEX(fs3270_mutex);47 48static void fs3270_wake_up(struct raw3270_request *rq, void *data)49{50 wake_up((wait_queue_head_t *)data);51}52 53static inline int fs3270_working(struct fs3270 *fp)54{55 /*56 * The fullscreen view is in working order if the view57 * has been activated AND the initial request is finished.58 */59 return fp->active && raw3270_request_final(fp->init);60}61 62static int fs3270_do_io(struct raw3270_view *view, struct raw3270_request *rq)63{64 struct fs3270 *fp;65 int rc;66 67 fp = (struct fs3270 *)view;68 rq->callback = fs3270_wake_up;69 rq->callback_data = &fp->wait;70 71 do {72 if (!fs3270_working(fp)) {73 /* Fullscreen view isn't ready yet. */74 rc = wait_event_interruptible(fp->wait,75 fs3270_working(fp));76 if (rc != 0)77 break;78 }79 rc = raw3270_start(view, rq);80 if (rc == 0) {81 /* Started successfully. Now wait for completion. */82 wait_event(fp->wait, raw3270_request_final(rq));83 }84 } while (rc == -EACCES);85 return rc;86}87 88/*89 * Switch to the fullscreen view.90 */91static void 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 100static void 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_pid(fp->fs_pid, SIGHUP, 1);108 }109 fp->rdbuf_size = 0;110 raw3270_request_reset(rq);111 wake_up(&fp->wait);112}113 114static int fs3270_activate(struct raw3270_view *view)115{116 struct fs3270 *fp;117 char *cp;118 int rc;119 120 fp = (struct fs3270 *)view;121 122 /* If an old init command is still running just return. */123 if (!raw3270_request_final(fp->init))124 return 0;125 126 raw3270_request_set_cmd(fp->init, TC_EWRITEA);127 raw3270_request_set_idal(fp->init, fp->rdbuf);128 fp->init->rescnt = 0;129 cp = dma64_to_virt(fp->rdbuf->data[0]);130 if (fp->rdbuf_size == 0) {131 /* No saved buffer. Just clear the screen. */132 fp->init->ccw.count = 1;133 fp->init->callback = fs3270_reset_callback;134 cp[0] = 0;135 } else {136 /* Restore fullscreen buffer saved by fs3270_deactivate. */137 fp->init->ccw.count = fp->rdbuf_size;138 fp->init->callback = fs3270_restore_callback;139 cp[0] = TW_KR;140 cp[1] = TO_SBA;141 cp[2] = cp[6];142 cp[3] = cp[7];143 cp[4] = TO_IC;144 cp[5] = TO_SBA;145 cp[6] = 0x40;146 cp[7] = 0x40;147 }148 rc = raw3270_start_locked(view, fp->init);149 fp->init->rc = rc;150 if (rc)151 fp->init->callback(fp->init, NULL);152 else153 fp->active = 1;154 return rc;155}156 157/*158 * Shutdown fullscreen view.159 */160static void 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] = dma64_add(fp->rdbuf->data[0], -5);168 fp->rdbuf->size += 5;169 170 /*171 * If the rdbuf command failed or the idal buffer is172 * to small for the amount of data returned by the173 * rdbuf command, then we have no choice but to send174 * a SIGHUP to the application.175 */176 if (rq->rc != 0 || rq->rescnt == 0) {177 if (fp->fs_pid)178 kill_pid(fp->fs_pid, SIGHUP, 1);179 fp->rdbuf_size = 0;180 } else {181 fp->rdbuf_size = fp->rdbuf->size - rq->rescnt;182 }183 raw3270_request_reset(rq);184 wake_up(&fp->wait);185}186 187static void 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 make202 * room for the TW_KR/TO_SBA/<address>/<address>/TO_IC sequence203 * in the activation command.204 */205 fp->rdbuf->data[0] = dma64_add(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 217static void fs3270_irq(struct fs3270 *fp, struct raw3270_request *rq,218 struct irb *irb)219{220 /* Handle ATTN. Set indication and wake waiters for attention. */221 if (irb->scsw.cmd.dstat & DEV_STAT_ATTENTION) {222 fp->attention = 1;223 wake_up(&fp->wait);224 }225 226 if (rq) {227 if (irb->scsw.cmd.dstat & DEV_STAT_UNIT_CHECK)228 rq->rc = -EIO;229 else230 /* Normal end. Copy residual count. */231 rq->rescnt = irb->scsw.cmd.count;232 }233}234 235/*236 * Process reads from fullscreen 3270.237 */238static ssize_t fs3270_read(struct file *filp, char __user *data,239 size_t count, loff_t *off)240{241 struct fs3270 *fp;242 struct raw3270_request *rq;243 struct idal_buffer *ib;244 ssize_t rc;245 246 if (count == 0 || count > 65535)247 return -EINVAL;248 fp = filp->private_data;249 if (!fp)250 return -ENODEV;251 ib = idal_buffer_alloc(count, 0);252 if (IS_ERR(ib))253 return -ENOMEM;254 rq = raw3270_request_alloc(0);255 if (!IS_ERR(rq)) {256 if (fp->read_command == 0 && fp->write_command != 0)257 fp->read_command = 6;258 raw3270_request_set_cmd(rq, fp->read_command ? : 2);259 raw3270_request_set_idal(rq, ib);260 rc = wait_event_interruptible(fp->wait, fp->attention);261 fp->attention = 0;262 if (rc == 0) {263 rc = fs3270_do_io(&fp->view, rq);264 if (rc == 0) {265 count -= rq->rescnt;266 if (idal_buffer_to_user(ib, data, count) != 0)267 rc = -EFAULT;268 else269 rc = count;270 }271 }272 raw3270_request_free(rq);273 } else {274 rc = PTR_ERR(rq);275 }276 idal_buffer_free(ib);277 return rc;278}279 280/*281 * Process writes to fullscreen 3270.282 */283static ssize_t fs3270_write(struct file *filp, const char __user *data,284 size_t count, loff_t *off)285{286 struct fs3270 *fp;287 struct raw3270_request *rq;288 struct idal_buffer *ib;289 int write_command;290 ssize_t rc;291 292 fp = filp->private_data;293 if (!fp)294 return -ENODEV;295 ib = idal_buffer_alloc(count, 0);296 if (IS_ERR(ib))297 return -ENOMEM;298 rq = raw3270_request_alloc(0);299 if (!IS_ERR(rq)) {300 if (idal_buffer_from_user(ib, data, count) == 0) {301 write_command = fp->write_command ? : 1;302 if (write_command == 5)303 write_command = 13;304 raw3270_request_set_cmd(rq, write_command);305 raw3270_request_set_idal(rq, ib);306 rc = fs3270_do_io(&fp->view, rq);307 if (rc == 0)308 rc = count - rq->rescnt;309 } else {310 rc = -EFAULT;311 }312 raw3270_request_free(rq);313 } else {314 rc = PTR_ERR(rq);315 }316 idal_buffer_free(ib);317 return rc;318}319 320/*321 * process ioctl commands for the tube driver322 */323static long fs3270_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)324{325 char __user *argp;326 struct fs3270 *fp;327 struct raw3270_iocb iocb;328 int rc;329 330 fp = filp->private_data;331 if (!fp)332 return -ENODEV;333 if (is_compat_task())334 argp = compat_ptr(arg);335 else336 argp = (char __user *)arg;337 rc = 0;338 mutex_lock(&fs3270_mutex);339 switch (cmd) {340 case TUBICMD:341 fp->read_command = arg;342 break;343 case TUBOCMD:344 fp->write_command = arg;345 break;346 case TUBGETI:347 rc = put_user(fp->read_command, argp);348 break;349 case TUBGETO:350 rc = put_user(fp->write_command, argp);351 break;352 case TUBGETMOD:353 iocb.model = fp->view.model;354 iocb.line_cnt = fp->view.rows;355 iocb.col_cnt = fp->view.cols;356 iocb.pf_cnt = 24;357 iocb.re_cnt = 20;358 iocb.map = 0;359 if (copy_to_user(argp, &iocb, sizeof(struct raw3270_iocb)))360 rc = -EFAULT;361 break;362 }363 mutex_unlock(&fs3270_mutex);364 return rc;365}366 367/*368 * Allocate fs3270 structure.369 */370static struct fs3270 *fs3270_alloc_view(void)371{372 struct fs3270 *fp;373 374 fp = kzalloc(sizeof(*fp), GFP_KERNEL);375 if (!fp)376 return ERR_PTR(-ENOMEM);377 fp->init = raw3270_request_alloc(0);378 if (IS_ERR(fp->init)) {379 kfree(fp);380 return ERR_PTR(-ENOMEM);381 }382 return fp;383}384 385/*386 * Free fs3270 structure.387 */388static void fs3270_free_view(struct raw3270_view *view)389{390 struct fs3270 *fp;391 392 fp = (struct fs3270 *)view;393 if (fp->rdbuf)394 idal_buffer_free(fp->rdbuf);395 raw3270_request_free(((struct fs3270 *)view)->init);396 kfree(view);397}398 399/*400 * Unlink fs3270 data structure from filp.401 */402static void fs3270_release(struct raw3270_view *view)403{404 struct fs3270 *fp;405 406 fp = (struct fs3270 *)view;407 if (fp->fs_pid)408 kill_pid(fp->fs_pid, SIGHUP, 1);409}410 411/* View to a 3270 device. Can be console, tty or fullscreen. */412static struct raw3270_fn fs3270_fn = {413 .activate = fs3270_activate,414 .deactivate = fs3270_deactivate,415 .intv = (void *)fs3270_irq,416 .release = fs3270_release,417 .free = fs3270_free_view418};419 420/*421 * This routine is called whenever a 3270 fullscreen device is opened.422 */423static int fs3270_open(struct inode *inode, struct file *filp)424{425 struct fs3270 *fp;426 struct idal_buffer *ib;427 int minor, rc = 0;428 429 if (imajor(file_inode(filp)) != IBM_FS3270_MAJOR)430 return -ENODEV;431 minor = iminor(file_inode(filp));432 /* Check for minor 0 multiplexer. */433 if (minor == 0) {434 struct tty_struct *tty = get_current_tty();435 436 if (!tty || tty->driver->major != IBM_TTY3270_MAJOR) {437 tty_kref_put(tty);438 return -ENODEV;439 }440 minor = tty->index;441 tty_kref_put(tty);442 }443 mutex_lock(&fs3270_mutex);444 /* Check if some other program is already using fullscreen mode. */445 fp = (struct fs3270 *)raw3270_find_view(&fs3270_fn, minor);446 if (!IS_ERR(fp)) {447 raw3270_put_view(&fp->view);448 rc = -EBUSY;449 goto out;450 }451 /* Allocate fullscreen view structure. */452 fp = fs3270_alloc_view();453 if (IS_ERR(fp)) {454 rc = PTR_ERR(fp);455 goto out;456 }457 458 init_waitqueue_head(&fp->wait);459 fp->fs_pid = get_pid(task_pid(current));460 rc = raw3270_add_view(&fp->view, &fs3270_fn, minor,461 RAW3270_VIEW_LOCK_BH);462 if (rc) {463 fs3270_free_view(&fp->view);464 goto out;465 }466 467 /* Allocate idal-buffer. */468 ib = idal_buffer_alloc(2 * fp->view.rows * fp->view.cols + 5, 0);469 if (IS_ERR(ib)) {470 raw3270_put_view(&fp->view);471 raw3270_del_view(&fp->view);472 rc = PTR_ERR(ib);473 goto out;474 }475 fp->rdbuf = ib;476 477 rc = raw3270_activate_view(&fp->view);478 if (rc) {479 raw3270_put_view(&fp->view);480 raw3270_del_view(&fp->view);481 goto out;482 }483 stream_open(inode, filp);484 filp->private_data = fp;485out:486 mutex_unlock(&fs3270_mutex);487 return rc;488}489 490/*491 * This routine is called when the 3270 tty is closed. We wait492 * for the remaining request to be completed. Then we clean up.493 */494static int fs3270_close(struct inode *inode, struct file *filp)495{496 struct fs3270 *fp;497 498 fp = filp->private_data;499 filp->private_data = NULL;500 if (fp) {501 put_pid(fp->fs_pid);502 fp->fs_pid = NULL;503 raw3270_reset(&fp->view);504 raw3270_put_view(&fp->view);505 raw3270_del_view(&fp->view);506 }507 return 0;508}509 510static const struct file_operations fs3270_fops = {511 .owner = THIS_MODULE, /* owner */512 .read = fs3270_read, /* read */513 .write = fs3270_write, /* write */514 .unlocked_ioctl = fs3270_ioctl, /* ioctl */515 .compat_ioctl = fs3270_ioctl, /* ioctl */516 .open = fs3270_open, /* open */517 .release = fs3270_close, /* release */518};519 520static void fs3270_create_cb(int minor)521{522 __register_chrdev(IBM_FS3270_MAJOR, minor, 1, "tub", &fs3270_fops);523 device_create(&class3270, NULL, MKDEV(IBM_FS3270_MAJOR, minor),524 NULL, "3270/tub%d", minor);525}526 527static void fs3270_destroy_cb(int minor)528{529 device_destroy(&class3270, MKDEV(IBM_FS3270_MAJOR, minor));530 __unregister_chrdev(IBM_FS3270_MAJOR, minor, 1, "tub");531}532 533static struct raw3270_notifier fs3270_notifier = {534 .create = fs3270_create_cb,535 .destroy = fs3270_destroy_cb,536};537 538/*539 * 3270 fullscreen driver initialization.540 */541static int __init fs3270_init(void)542{543 int rc;544 545 rc = __register_chrdev(IBM_FS3270_MAJOR, 0, 1, "fs3270", &fs3270_fops);546 if (rc)547 return rc;548 device_create(&class3270, NULL, MKDEV(IBM_FS3270_MAJOR, 0),549 NULL, "3270/tub");550 raw3270_register_notifier(&fs3270_notifier);551 return 0;552}553 554static void __exit fs3270_exit(void)555{556 raw3270_unregister_notifier(&fs3270_notifier);557 device_destroy(&class3270, MKDEV(IBM_FS3270_MAJOR, 0));558 __unregister_chrdev(IBM_FS3270_MAJOR, 0, 1, "fs3270");559}560 561MODULE_DESCRIPTION("IBM/3270 Driver - fullscreen driver");562MODULE_LICENSE("GPL");563MODULE_ALIAS_CHARDEV_MAJOR(IBM_FS3270_MAJOR);564 565module_init(fs3270_init);566module_exit(fs3270_exit);567