con3270.c

linux-2.6.15.6

/*
 *  drivers/s390/char/con3270.c
 *    IBM/3270 Driver - console view.
 *
 *  Author(s):
 *    Original 3270 Code for 2.4 written by Richard Hitt (UTS Global)
 *    Rewritten for 2.5 by Martin Schwidefsky <[e-mail]>
 *	-- Copyright (C) 2003 IBM Deutschland Entwicklung GmbH, IBM Corporation
 */

#include <linux/config.h>
#include <linux/bootmem.h>
#include <linux/console.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/list.h>
#include <linux/types.h>

#include <asm/ccwdev.h>
#include <asm/cio.h>
#include <asm/cpcmd.h>
#include <asm/ebcdic.h>

#include "raw3270.h"
#include "ctrlchar.h"

#define CON3270_OUTPUT_BUFFER_SIZE 1024
#define CON3270_STRING_PAGES 4

static struct raw3270_fn con3270_fn;

/*
 * Main 3270 console view data structure.
 */
struct con3270 {
	struct raw3270_view view;
	spinlock_t lock;
	struct list_head freemem;	/* list of free memory for strings. */

	/* Output stuff. */
	struct list_head lines;		/* list of lines. */
	struct list_head update;	/* list of lines to update. */
	int line_nr;			/* line number for next update. */
	int nr_lines;			/* # lines in list. */
	int nr_up;			/* # lines up in history. */
	unsigned long update_flags;	/* Update indication bits. */
	struct string *cline;		/* current output line. */
	struct string *status;		/* last line of display. */
	struct raw3270_request *write;	/* single write request. */
	struct timer_list timer;

	/* Input stuff. */
	struct string *input;		/* input string for read request. */
	struct raw3270_request *read;	/* single read request. */
	struct raw3270_request *kreset;	/* single keyboard reset request. */
	struct tasklet_struct readlet;	/* tasklet to issue read request. */
};

static struct con3270 *condev;

/* con3270->update_flags. See con3270_update for details. */
#define CON_UPDATE_ERASE	1	/* Use EWRITEA instead of WRITE. */
#define CON_UPDATE_LIST		2	/* Update lines in tty3270->update. */
#define CON_UPDATE_STATUS	4	/* Update status line. */
#define CON_UPDATE_ALL		7

static void con3270_update(struct con3270 *);

/*
 * Setup timeout for a device. On timeout trigger an update.
 */
void
con3270_set_timer(struct con3270 *cp, int expires)
{
	if (expires == 0) {
		if (timer_pending(&cp->timer))
			del_timer(&cp->timer);
		return;
	}
	if (timer_pending(&cp->timer) &&
	    mod_timer(&cp->timer, jiffies + expires))
		return;
	cp->timer.function = (void (*)(unsigned long)) con3270_update;
	cp->timer.data = (unsigned long) cp;
	cp->timer.expires = jiffies + expires;
	add_timer(&cp->timer);
}

/*
 * The status line is the last line of the screen. It shows the string
 * "console view" in the lower left corner and "Running"/"More..."/"Holding"
 * in the lower right corner of the screen.
 */
static void
con3270_update_status(struct con3270 *cp)
{
	char *str;

	str = (cp->nr_up != 0) ? "History" : "Running";
	memcpy(cp->status->string + 24, str, 7);
	codepage_convert(cp->view.ascebc, cp->status->string + 24, 7);
	cp->update_flags |= CON_UPDATE_STATUS;
}

static void
con3270_create_status(struct con3270 *cp)
{
	static const unsigned char blueprint[] =
		{ TO_SBA, 0, 0, TO_SF,TF_LOG,TO_SA,TAT_COLOR, TAC_GREEN,
		  'c','o','n','s','o','l','e',' ','v','i','e','w',
		  TO_RA,0,0,0,'R','u','n','n','i','n','g',TO_SF,TF_LOG };

	cp->status = alloc_string(&cp->freemem, sizeof(blueprint));
	/* Copy blueprint to status line */
	memcpy(cp->status->string, blueprint, sizeof(blueprint));
	/* Set TO_RA addresses. */
	raw3270_buffer_address(cp->view.dev, cp->status->string + 1,
			       cp->view.cols * (cp->view.rows - 1));
	raw3270_buffer_address(cp->view.dev, cp->status->string + 21,
			       cp->view.cols * cp->view.rows - 8);
	/* Convert strings to ebcdic. */
	codepage_convert(cp->view.ascebc, cp->status->string + 8, 12);
	codepage_convert(cp->view.ascebc, cp->status->string + 24, 7);
}

/*
 * Set output offsets to 3270 datastream fragment of a console string.
 */
static void
con3270_update_string(struct con3270 *cp, struct string *s, int nr)
{
	if (s->len >= cp->view.cols - 5)
		return;
	raw3270_buffer_address(cp->view.dev, s->string + s->len - 3,
			       cp->view.cols * (nr + 1));
}

/*
 * Rebuild update list to print all lines.
 */
static void
con3270_rebuild_update(struct con3270 *cp)
{
	struct string *s, *n;
	int nr;

	/* 
	 * Throw away update list and create a new one,
	 * containing all lines that will fit on the screen.
	 */
	list_for_each_entry_safe(s, n, &cp->update, update)
		list_del_init(&s->update);
	nr = cp->view.rows - 2 + cp->nr_up;
	list_for_each_entry_reverse(s, &cp->lines, list) {
		if (nr < cp->view.rows - 1)
			list_add(&s->update, &cp->update);
		if (--nr < 0)
			break;
	}
	cp->line_nr = 0;
	cp->update_flags |= CON_UPDATE_LIST;
}

/*
 * Alloc string for size bytes. Free strings from history if necessary.
 */
static struct string *
con3270_alloc_string(struct con3270 *cp, size_t size)
{
	struct string *s, *n;

	s = alloc_string(&cp->freemem, size);
	if (s)
		return s;
	list_for_each_entry_safe(s, n, &cp->lines, list) {
		list_del(&s->list);
		if (!list_empty(&s->update))
			list_del(&s->update);
		cp->nr_lines--;
		if (free_string(&cp->freemem, s) >= size)
			break;
	}
	s = alloc_string(&cp->freemem, size);
	BUG_ON(!s);
	if (cp->nr_up != 0 && cp->nr_up + cp->view.rows > cp->nr_lines) {
		cp->nr_up = cp->nr_lines - cp->view.rows + 1;
		con3270_rebuild_update(cp);
		con3270_update_status(cp);
	}
	return s;
}

/*
 * Write completion callback.
 */
static void
con3270_write_callback(struct raw3270_request *rq, void *data)
{
	raw3270_request_reset(rq);
	xchg(&((struct con3270 *) rq->view)->write, rq);
}

/*
 * Update console display.
 */
static void
con3270_update(struct con3270 *cp)
{
	struct raw3270_request *wrq;
	char wcc, prolog[6];
	unsigned long flags;
	unsigned long updated;
	struct string *s, *n;
	int rc;

	if (cp->view.dev)
		raw3270_activate_view(&cp->view);

	wrq = xchg(&cp->write, 0);
	if (!wrq) {
		con3270_set_timer(cp, 1);
		return;
	}

	spin_lock_irqsave(&cp->view.lock, flags);
	updated = 0;
	if (cp->update_flags & CON_UPDATE_ERASE) {
		/* Use erase write alternate to initialize display. */
		raw3270_request_set_cmd(wrq, TC_EWRITEA);
		updated |= CON_UPDATE_ERASE;
	} else
		raw3270_request_set_cmd(wrq, TC_WRITE);

	wcc = TW_NONE;
	raw3270_request_add_data(wrq, &wcc, 1);

	/*
	 * Update status line.
	 */
	if (cp->update_flags & CON_UPDATE_STATUS)
		if (raw3270_request_add_data(wrq, cp->status->string,
					     cp->status->len) == 0)
			updated |= CON_UPDATE_STATUS;

	if (cp->update_flags & CON_UPDATE_LIST) {
		prolog[0] = TO_SBA;
		prolog[3] = TO_SA;
		prolog[4] = TAT_COLOR;
		prolog[5] = TAC_TURQ;
		raw3270_buffer_address(cp->view.dev, prolog + 1,
				       cp->view.cols * cp->line_nr);
		raw3270_request_add_data(wrq, prolog, 6);
		/* Write strings in the update list to the screen. */
		list_for_each_entry_safe(s, n, &cp->update, update) {
			if (s != cp->cline)
				con3270_update_string(cp, s, cp->line_nr);
			if (raw3270_request_add_data(wrq, s->string,
						     s->len) != 0)
				break;
			list_del_init(&s->update);
			if (s != cp->cline)
				cp->line_nr++;
		}
		if (list_empty(&cp->update))
			updated |= CON_UPDATE_LIST;
	}
	wrq->callback = con3270_write_callback;
	rc = raw3270_start(&cp->view, wrq);
	if (rc == 0) {
		cp->update_flags &= ~updated;
		if (cp->update_flags)
			con3270_set_timer(cp, 1);
	} else {
		raw3270_request_reset(wrq);
		xchg(&cp->write, wrq);
	}
	spin_unlock_irqrestore(&cp->view.lock, flags);
}

/*
 * Read tasklet.
 */
static void
con3270_read_tasklet(struct raw3270_request *rrq)
{
	static char kreset_data = TW_KR;
	struct con3270 *cp;
	unsigned long flags;
	int nr_up, deactivate;

	cp = (struct con3270 *) rrq->view;
	spin_lock_irqsave(&cp->view.lock, flags);
	nr_up = cp->nr_up;
	deactivate = 0;
	/* Check aid byte. */
	switch (cp->input->string[0]) {
	case 0x7d:	/* enter: jump to bottom. */
		nr_up = 0;
		break;
	case 0xf3:	/* PF3: deactivate the console view. */
		deactivate = 1;
		break;
	case 0x6d:	/* clear: start from scratch. */
		con3270_rebuild_update(cp);
		cp->update_flags = CON_UPDATE_ALL;
		con3270_set_timer(cp, 1);
		break;
	case 0xf7:	/* PF7: do a page up in the console log. */
		nr_up += cp->view.rows - 2;
		if (nr_up + cp->view.rows - 1 > cp->nr_lines) {
			nr_up = cp->nr_lines - cp->view.rows + 1;
			if (nr_up < 0)
				nr_up = 0;
		}
		break;
	case 0xf8:	/* PF8: do a page down in the console log. */
		nr_up -= cp->view.rows - 2;
		if (nr_up < 0)
			nr_up = 0;
		break;