1 files changed, 576 insertions, 0 deletions
diff --git a/drivers/s390/char/fs3270.c b/drivers/s390/char/fs3270.c
new file mode 100644
index 000000000..4c4683d87
--- /dev/null
+++ b/drivers/s390/char/fs3270.c
@@ -0,0 +1,576 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * IBM/3270 Driver - fullscreen driver.
+ *
+ * Author(s):
+ *   Original 3270 Code for 2.4 written by Richard Hitt (UTS Global)
+ *   Rewritten for 2.5/2.6 by Martin Schwidefsky <schwidefsky@de.ibm.com>
+ *     Copyright IBM Corp. 2003, 2009
+ */
+
+#include <linux/memblock.h>
+#include <linux/console.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/compat.h>
+#include <linux/sched/signal.h>
+#include <linux/module.h>
+#include <linux/list.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+
+#include <asm/ccwdev.h>
+#include <asm/cio.h>
+#include <asm/ebcdic.h>
+#include <asm/idals.h>
+
+#include "raw3270.h"
+#include "ctrlchar.h"
+
+static struct raw3270_fn fs3270_fn;
+
+struct fs3270 {
+	struct raw3270_view view;
+	struct pid *fs_pid;		/* Pid of controlling program. */
+	int read_command;		/* ccw command to use for reads. */
+	int write_command;		/* ccw command to use for writes. */
+	int attention;			/* Got attention. */
+	int active;			/* Fullscreen view is active. */
+	struct raw3270_request *init;	/* single init request. */
+	wait_queue_head_t wait;		/* Init & attention wait queue. */
+	struct idal_buffer *rdbuf;	/* full-screen-deactivate buffer */
+	size_t rdbuf_size;		/* size of data returned by RDBUF */
+};
+
+static DEFINE_MUTEX(fs3270_mutex);
+
+static void
+fs3270_wake_up(struct raw3270_request *rq, void *data)
+{
+	wake_up((wait_queue_head_t *) data);
+}
+
+static inline int
+fs3270_working(struct fs3270 *fp)
+{
+	/*
+	 * The fullscreen view is in working order if the view
+	 * has been activated AND the initial request is finished.
+	 */
+	return fp->active && raw3270_request_final(fp->init);
+}
+
+static int
+fs3270_do_io(struct raw3270_view *view, struct raw3270_request *rq)
+{
+	struct fs3270 *fp;
+	int rc;
+
+	fp = (struct fs3270 *) view;
+	rq->callback = fs3270_wake_up;
+	rq->callback_data = &fp->wait;
+
+	do {
+		if (!fs3270_working(fp)) {
+			/* Fullscreen view isn't ready yet. */
+			rc = wait_event_interruptible(fp->wait,
+						      fs3270_working(fp));
+			if (rc != 0)
+				break;
+		}
+		rc = raw3270_start(view, rq);
+		if (rc == 0) {
+			/* Started successfully. Now wait for completion. */
+			wait_event(fp->wait, raw3270_request_final(rq));
+		}
+	} while (rc == -EACCES);
+	return rc;
+}
+
+/*
+ * Switch to the fullscreen view.
+ */
+static void
+fs3270_reset_callback(struct raw3270_request *rq, void *data)
+{
+	struct fs3270 *fp;
+
+	fp = (struct fs3270 *) rq->view;
+	raw3270_request_reset(rq);
+	wake_up(&fp->wait);
+}
+
+static void
+fs3270_restore_callback(struct raw3270_request *rq, void *data)
+{
+	struct fs3270 *fp;
+
+	fp = (struct fs3270 *) rq->view;
+	if (rq->rc != 0 || rq->rescnt != 0) {
+		if (fp->fs_pid)
+			kill_pid(fp->fs_pid, SIGHUP, 1);
+	}
+	fp->rdbuf_size = 0;
+	raw3270_request_reset(rq);
+	wake_up(&fp->wait);
+}
+
+static int
+fs3270_activate(struct raw3270_view *view)
+{
+	struct fs3270 *fp;
+	char *cp;
+	int rc;
+
+	fp = (struct fs3270 *) view;
+
+	/* If an old init command is still running just return. */
+	if (!raw3270_request_final(fp->init))
+		return 0;
+
+	if (fp->rdbuf_size == 0) {
+		/* No saved buffer. Just clear the screen. */
+		raw3270_request_set_cmd(fp->init, TC_EWRITEA);
+		fp->init->callback = fs3270_reset_callback;
+	} else {
+		/* Restore fullscreen buffer saved by fs3270_deactivate. */
+		raw3270_request_set_cmd(fp->init, TC_EWRITEA);
+		raw3270_request_set_idal(fp->init, fp->rdbuf);
+		fp->init->ccw.count = fp->rdbuf_size;
+		cp = fp->rdbuf->data[0];
+		cp[0] = TW_KR;
+		cp[1] = TO_SBA;
+		cp[2] = cp[6];
+		cp[3] = cp[7];
+		cp[4] = TO_IC;
+		cp[5] = TO_SBA;
+		cp[6] = 0x40;
+		cp[7] = 0x40;
+		fp->init->rescnt = 0;
+		fp->init->callback = fs3270_restore_callback;
+	}
+	rc = fp->init->rc = raw3270_start_locked(view, fp->init);
+	if (rc)
+		fp->init->callback(fp->init, NULL);
+	else
+		fp->active = 1;
+	return rc;
+}
+
+/*
+ * Shutdown fullscreen view.
+ */
+static void
+fs3270_save_callback(struct raw3270_request *rq, void *data)
+{
+	struct fs3270 *fp;
+
+	fp = (struct fs3270 *) rq->view;
+
+	/* Correct idal buffer element 0 address. */
+	fp->rdbuf->data[0] -= 5;
+	fp->rdbuf->size += 5;
+
+	/*
+	 * If the rdbuf command failed or the idal buffer is
+	 * to small for the amount of data returned by the
+	 * rdbuf command, then we have no choice but to send
+	 * a SIGHUP to the application.
+	 */
+	if (rq->rc != 0 || rq->rescnt == 0) {
+		if (fp->fs_pid)
+			kill_pid(fp->fs_pid, SIGHUP, 1);
+		fp->rdbuf_size = 0;
+	} else
+		fp->rdbuf_size = fp->rdbuf->size - rq->rescnt;
+	raw3270_request_reset(rq);
+	wake_up(&fp->wait);
+}
+
+static void
+fs3270_deactivate(struct raw3270_view *view)
+{
+	struct fs3270 *fp;
+
+	fp = (struct fs3270 *) view;
+	fp->active = 0;
+
+	/* If an old init command is still running just return. */
+	if (!raw3270_request_final(fp->init))
+		return;
+
+	/* Prepare read-buffer request. */
+	raw3270_request_set_cmd(fp->init, TC_RDBUF);
+	/*
+	 * Hackish: skip first 5 bytes of the idal buffer to make
+	 * room for the TW_KR/TO_SBA/<address>/<address>/TO_IC sequence
+	 * in the activation command.
+	 */
+	fp->rdbuf->data[0] += 5;
+	fp->rdbuf->size -= 5;
+	raw3270_request_set_idal(fp->init, fp->rdbuf);
+	fp->init->rescnt = 0;
+	fp->init->callback = fs3270_save_callback;
+
+	/* Start I/O to read in the 3270 buffer. */
+	fp->init->rc = raw3270_start_locked(view, fp->init);
+	if (fp->init->rc)
+		fp->init->callback(fp->init, NULL);
+}
+
+static void
+fs3270_irq(struct fs3270 *fp, struct raw3270_request *rq, struct irb *irb)
+{
+	/* Handle ATTN. Set indication and wake waiters for attention. */
+	if (irb->scsw.cmd.dstat & DEV_STAT_ATTENTION) {
+		fp->attention = 1;
+		wake_up(&fp->wait);
+	}
+
+	if (rq) {
+		if (irb->scsw.cmd.dstat & DEV_STAT_UNIT_CHECK)
+			rq->rc = -EIO;
+		else
+			/* Normal end. Copy residual count. */
+			rq->rescnt = irb->scsw.cmd.count;
+	}
+}
+
+/*
+ * Process reads from fullscreen 3270.
+ */
+static ssize_t
+fs3270_read(struct file *filp, char __user *data, size_t count, loff_t *off)
+{
+	struct fs3270 *fp;
+	struct raw3270_request *rq;
+	struct idal_buffer *ib;
+	ssize_t rc;
+	
+	if (count == 0 || count > 65535)
+		return -EINVAL;
+	fp = filp->private_data;
+	if (!fp)
+		return -ENODEV;
+	ib = idal_buffer_alloc(count, 0);
+	if (IS_ERR(ib))
+		return -ENOMEM;
+	rq = raw3270_request_alloc(0);
+	if (!IS_ERR(rq)) {
+		if (fp->read_command == 0 && fp->write_command != 0)
+			fp->read_command = 6;
+		raw3270_request_set_cmd(rq, fp->read_command ? : 2);
+		raw3270_request_set_idal(rq, ib);
+		rc = wait_event_interruptible(fp->wait, fp->attention);
+		fp->attention = 0;
+		if (rc == 0) {
+			rc = fs3270_do_io(&fp->view, rq);
+			if (rc == 0) {
+				count -= rq->rescnt;
+				if (idal_buffer_to_user(ib, data, count) != 0)
+					rc = -EFAULT;
+				else
+					rc = count;
+
+			}
+		}
+		raw3270_request_free(rq);
+	} else
+		rc = PTR_ERR(rq);
+	idal_buffer_free(ib);
+	return rc;
+}
+
+/*
+ * Process writes to fullscreen 3270.
+ */
+static ssize_t
+fs3270_write(struct file *filp, const char __user *data, size_t count, loff_t *off)
+{
+	struct fs3270 *fp;
+	struct raw3270_request *rq;
+	struct idal_buffer *ib;
+	int write_command;
+	ssize_t rc;
+
+	fp = filp->private_data;
+	if (!fp)
+		return -ENODEV;
+	ib = idal_buffer_alloc(count, 0);
+	if (IS_ERR(ib))
+		return -ENOMEM;
+	rq = raw3270_request_alloc(0);
+	if (!IS_ERR(rq)) {
+		if (idal_buffer_from_user(ib, data, count) == 0) {
+			write_command = fp->write_command ? : 1;
+			if (write_command == 5)
+				write_command = 13;
+			raw3270_request_set_cmd(rq, write_command);
+			raw3270_request_set_idal(rq, ib);
+			rc = fs3270_do_io(&fp->view, rq);
+			if (rc == 0)
+				rc = count - rq->rescnt;
+		} else
+			rc = -EFAULT;
+		raw3270_request_free(rq);
+	} else
+		rc = PTR_ERR(rq);
+	idal_buffer_free(ib);
+	return rc;
+}
+
+/*
+ * process ioctl commands for the tube driver
+ */
+static long
+fs3270_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
+{
+	char __user *argp;
+	struct fs3270 *fp;
+	struct raw3270_iocb iocb;
+	int rc;
+
+	fp = filp->private_data;
+	if (!fp)
+		return -ENODEV;
+	if (is_compat_task())
+		argp = compat_ptr(arg);
+	else
+		argp = (char __user *)arg;
+	rc = 0;
+	mutex_lock(&fs3270_mutex);
+	switch (cmd) {
+	case TUBICMD:
+		fp->read_command = arg;
+		break;
+	case TUBOCMD:
+		fp->write_command = arg;
+		break;
+	case TUBGETI:
+		rc = put_user(fp->read_command, argp);
+		break;
+	case TUBGETO:
+		rc = put_user(fp->write_command, argp);
+		break;
+	case TUBGETMOD:
+		iocb.model = fp->view.model;
+		iocb.line_cnt = fp->view.rows;
+		iocb.col_cnt = fp->view.cols;
+		iocb.pf_cnt = 24;
+		iocb.re_cnt = 20;
+		iocb.map = 0;
+		if (copy_to_user(argp, &iocb, sizeof(struct raw3270_iocb)))
+			rc = -EFAULT;
+		break;
+	}
+	mutex_unlock(&fs3270_mutex);
+	return rc;
+}
+
+/*
+ * Allocate fs3270 structure.
+ */
+static struct fs3270 *
+fs3270_alloc_view(void)
+{
+	struct fs3270 *fp;
+
+	fp = kzalloc(sizeof(struct fs3270),GFP_KERNEL);
+	if (!fp)
+		return ERR_PTR(-ENOMEM);
+	fp->init = raw3270_request_alloc(0);
+	if (IS_ERR(fp->init)) {
+		kfree(fp);
+		return ERR_PTR(-ENOMEM);
+	}
+	return fp;
+}
+
+/*
+ * Free fs3270 structure.
+ */
+static void
+fs3270_free_view(struct raw3270_view *view)
+{
+	struct fs3270 *fp;
+
+	fp = (struct fs3270 *) view;
+	if (fp->rdbuf)
+		idal_buffer_free(fp->rdbuf);
+	raw3270_request_free(((struct fs3270 *) view)->init);
+	kfree(view);
+}
+
+/*
+ * Unlink fs3270 data structure from filp.
+ */
+static void
+fs3270_release(struct raw3270_view *view)
+{
+	struct fs3270 *fp;
+
+	fp = (struct fs3270 *) view;
+	if (fp->fs_pid)
+		kill_pid(fp->fs_pid, SIGHUP, 1);
+}
+
+/* View to a 3270 device. Can be console, tty or fullscreen. */
+static struct raw3270_fn fs3270_fn = {
+	.activate = fs3270_activate,
+	.deactivate = fs3270_deactivate,
+	.intv = (void *) fs3270_irq,
+	.release = fs3270_release,
+	.free = fs3270_free_view
+};
+
+/*
+ * This routine is called whenever a 3270 fullscreen device is opened.
+ */
+static int
+fs3270_open(struct inode *inode, struct file *filp)
+{
+	struct fs3270 *fp;
+	struct idal_buffer *ib;
+	int minor, rc = 0;
+
+	if (imajor(file_inode(filp)) != IBM_FS3270_MAJOR)
+		return -ENODEV;
+	minor = iminor(file_inode(filp));
+	/* Check for minor 0 multiplexer. */
+	if (minor == 0) {
+		struct tty_struct *tty = get_current_tty();
+		if (!tty || tty->driver->major != IBM_TTY3270_MAJOR) {
+			tty_kref_put(tty);
+			return -ENODEV;
+		}
+		minor = tty->index;
+		tty_kref_put(tty);
+	}
+	mutex_lock(&fs3270_mutex);
+	/* Check if some other program is already using fullscreen mode. */
+	fp = (struct fs3270 *) raw3270_find_view(&fs3270_fn, minor);
+	if (!IS_ERR(fp)) {
+		raw3270_put_view(&fp->view);
+		rc = -EBUSY;
+		goto out;
+	}
+	/* Allocate fullscreen view structure. */
+	fp = fs3270_alloc_view();
+	if (IS_ERR(fp)) {
+		rc = PTR_ERR(fp);
+		goto out;
+	}
+
+	init_waitqueue_head(&fp->wait);
+	fp->fs_pid = get_pid(task_pid(current));
+	rc = raw3270_add_view(&fp->view, &fs3270_fn, minor,
+			      RAW3270_VIEW_LOCK_BH);
+	if (rc) {
+		fs3270_free_view(&fp->view);
+		goto out;
+	}
+
+	/* Allocate idal-buffer. */
+	ib = idal_buffer_alloc(2*fp->view.rows*fp->view.cols + 5, 0);
+	if (IS_ERR(ib)) {
+		raw3270_put_view(&fp->view);
+		raw3270_del_view(&fp->view);
+		rc = PTR_ERR(ib);
+		goto out;
+	}
+	fp->rdbuf = ib;
+
+	rc = raw3270_activate_view(&fp->view);
+	if (rc) {
+		raw3270_put_view(&fp->view);
+		raw3270_del_view(&fp->view);
+		goto out;
+	}
+	stream_open(inode, filp);
+	filp->private_data = fp;
+out:
+	mutex_unlock(&fs3270_mutex);
+	return rc;
+}
+
+/*
+ * This routine is called when the 3270 tty is closed. We wait
+ * for the remaining request to be completed. Then we clean up.
+ */
+static int
+fs3270_close(struct inode *inode, struct file *filp)
+{
+	struct fs3270 *fp;
+
+	fp = filp->private_data;
+	filp->private_data = NULL;
+	if (fp) {
+		put_pid(fp->fs_pid);
+		fp->fs_pid = NULL;
+		raw3270_reset(&fp->view);
+		raw3270_put_view(&fp->view);
+		raw3270_del_view(&fp->view);
+	}
+	return 0;
+}
+
+static const struct file_operations fs3270_fops = {
+	.owner		 = THIS_MODULE,		/* owner */
+	.read		 = fs3270_read,		/* read */
+	.write		 = fs3270_write,	/* write */
+	.unlocked_ioctl	 = fs3270_ioctl,	/* ioctl */
+	.compat_ioctl	 = fs3270_ioctl,	/* ioctl */
+	.open		 = fs3270_open,		/* open */
+	.release	 = fs3270_close,	/* release */
+	.llseek		= no_llseek,
+};
+
+static void fs3270_create_cb(int minor)
+{
+	__register_chrdev(IBM_FS3270_MAJOR, minor, 1, "tub", &fs3270_fops);
+	device_create(class3270, NULL, MKDEV(IBM_FS3270_MAJOR, minor),
+		      NULL, "3270/tub%d", minor);
+}
+
+static void fs3270_destroy_cb(int minor)
+{
+	device_destroy(class3270, MKDEV(IBM_FS3270_MAJOR, minor));
+	__unregister_chrdev(IBM_FS3270_MAJOR, minor, 1, "tub");
+}
+
+static struct raw3270_notifier fs3270_notifier =
+{
+	.create = fs3270_create_cb,
+	.destroy = fs3270_destroy_cb,
+};
+
+/*
+ * 3270 fullscreen driver initialization.
+ */
+static int __init
+fs3270_init(void)
+{
+	int rc;
+
+	rc = __register_chrdev(IBM_FS3270_MAJOR, 0, 1, "fs3270", &fs3270_fops);
+	if (rc)
+		return rc;
+	device_create(class3270, NULL, MKDEV(IBM_FS3270_MAJOR, 0),
+		      NULL, "3270/tub");
+	raw3270_register_notifier(&fs3270_notifier);
+	return 0;
+}
+
+static void __exit
+fs3270_exit(void)
+{
+	raw3270_unregister_notifier(&fs3270_notifier);
+	device_destroy(class3270, MKDEV(IBM_FS3270_MAJOR, 0));
+	__unregister_chrdev(IBM_FS3270_MAJOR, 0, 1, "fs3270");
+}
+
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_CHARDEV_MAJOR(IBM_FS3270_MAJOR);
+
+module_init(fs3270_init);
+module_exit(fs3270_exit);