tty3270.c

linux-2.6.15.6

 */
static void
tty3270_issue_read(struct tty3270 *tp, int lock)
{
	struct raw3270_request *rrq;
	int rc;

	rrq = xchg(&tp->read, 0);
	if (!rrq)
		/* Read already scheduled. */
		return;
	rrq->callback = tty3270_read_callback;
	rrq->callback_data = tp;
	raw3270_request_set_cmd(rrq, TC_READMOD);
	raw3270_request_set_data(rrq, tp->input->string, tp->input->len);
	/* Issue the read modified request. */
	if (lock) {
		rc = raw3270_start(&tp->view, rrq);
	} else
		rc = raw3270_start_irq(&tp->view, rrq);
	if (rc) {
		raw3270_request_reset(rrq);
		xchg(&tp->read, rrq);
	}
}

/*
 * Switch to the tty view.
 */
static int
tty3270_activate(struct raw3270_view *view)
{
	struct tty3270 *tp;
	unsigned long flags;

	tp = (struct tty3270 *) view;
	spin_lock_irqsave(&tp->view.lock, flags);
	tp->nr_up = 0;
	tty3270_rebuild_update(tp);
	tty3270_update_status(tp);
	tp->update_flags = TTY_UPDATE_ALL;
	tty3270_set_timer(tp, 1);
	spin_unlock_irqrestore(&tp->view.lock, flags);
	return 0;
}

static void
tty3270_deactivate(struct raw3270_view *view)
{
}

static int
tty3270_irq(struct tty3270 *tp, struct raw3270_request *rq, struct irb *irb)
{
	/* Handle ATTN. Schedule tasklet to read aid. */
	if (irb->scsw.dstat & DEV_STAT_ATTENTION) {
		if (!tp->throttle)
			tty3270_issue_read(tp, 0);
		else
			tp->attn = 1;
	}

	if (rq) {
		if (irb->scsw.dstat & DEV_STAT_UNIT_CHECK)
			rq->rc = -EIO;
		else
			/* Normal end. Copy residual count. */
			rq->rescnt = irb->scsw.count;
	}
	return RAW3270_IO_DONE;
}

/*
 * Allocate tty3270 structure.
 */
static struct tty3270 *
tty3270_alloc_view(void)
{
	struct tty3270 *tp;
	int pages;

	tp = kmalloc(sizeof(struct tty3270),GFP_KERNEL);
	if (!tp)
		goto out_err;
	memset(tp, 0, sizeof(struct tty3270));
	tp->freemem_pages =
		kmalloc(sizeof(void *) * TTY3270_STRING_PAGES, GFP_KERNEL);
	if (!tp->freemem_pages)
		goto out_tp;
	INIT_LIST_HEAD(&tp->freemem);
	init_timer(&tp->timer);
	for (pages = 0; pages < TTY3270_STRING_PAGES; pages++) {
		tp->freemem_pages[pages] = (void *)
			__get_free_pages(GFP_KERNEL|GFP_DMA, 0);
		if (!tp->freemem_pages[pages])
			goto out_pages;
		add_string_memory(&tp->freemem,
				  tp->freemem_pages[pages], PAGE_SIZE);
	}
	tp->write = raw3270_request_alloc(TTY3270_OUTPUT_BUFFER_SIZE);
	if (IS_ERR(tp->write))
		goto out_pages;
	tp->read = raw3270_request_alloc(0);
	if (IS_ERR(tp->read))
		goto out_write;
	tp->kreset = raw3270_request_alloc(1);
	if (IS_ERR(tp->kreset))
		goto out_read;
	tp->kbd = kbd_alloc();
	if (!tp->kbd)
		goto out_reset;
	return tp;

out_reset:
	raw3270_request_free(tp->kreset);
out_read:
	raw3270_request_free(tp->read);
out_write:
	raw3270_request_free(tp->write);
out_pages:
	while (pages--)
		free_pages((unsigned long) tp->freemem_pages[pages], 0);
	kfree(tp->freemem_pages);
out_tp:
	kfree(tp);
out_err:
	return ERR_PTR(-ENOMEM);
}

/*
 * Free tty3270 structure.
 */
static void
tty3270_free_view(struct tty3270 *tp)
{
	int pages;

	kbd_free(tp->kbd);
	raw3270_request_free(tp->kreset);
	raw3270_request_free(tp->read);
	raw3270_request_free(tp->write);
	for (pages = 0; pages < TTY3270_STRING_PAGES; pages++)
		free_pages((unsigned long) tp->freemem_pages[pages], 0);
	kfree(tp->freemem_pages);
	kfree(tp);
}

/*
 * Allocate tty3270 screen.
 */
static int
tty3270_alloc_screen(struct tty3270 *tp)
{
	unsigned long size;
	int lines;

	size = sizeof(struct tty3270_line) * (tp->view.rows - 2);
	tp->screen = kmalloc(size, GFP_KERNEL);
	if (!tp->screen)
		goto out_err;
	memset(tp->screen, 0, size);
	for (lines = 0; lines < tp->view.rows - 2; lines++) {
		size = sizeof(struct tty3270_cell) * tp->view.cols;
		tp->screen[lines].cells = kmalloc(size, GFP_KERNEL);
		if (!tp->screen[lines].cells)
			goto out_screen;
		memset(tp->screen[lines].cells, 0, size);
	}
	return 0;
out_screen:
	while (lines--)
		kfree(tp->screen[lines].cells);
	kfree(tp->screen);
out_err:
	return -ENOMEM;
}

/*
 * Free tty3270 screen.
 */
static void
tty3270_free_screen(struct tty3270 *tp)
{
	int lines;

	for (lines = 0; lines < tp->view.rows - 2; lines++)
		kfree(tp->screen[lines].cells);
	kfree(tp->screen);
}

/*
 * Unlink tty3270 data structure from tty.
 */
static void
tty3270_release(struct raw3270_view *view)
{
	struct tty3270 *tp;
	struct tty_struct *tty;

	tp = (struct tty3270 *) view;
	tty = tp->tty;
	if (tty) {
		tty->driver_data = 0;
		tp->tty = tp->kbd->tty = 0;
		tty_hangup(tty);
		raw3270_put_view(&tp->view);
	}
}

/*
 * Free tty3270 data structure
 */
static void
tty3270_free(struct raw3270_view *view)
{
	tty3270_free_screen((struct tty3270 *) view);
	tty3270_free_view((struct tty3270 *) view);
}

/*
 * Delayed freeing of tty3270 views.
 */
static void
tty3270_del_views(void)
{
	struct tty3270 *tp;
	int i;

	for (i = 0; i < tty3270_max_index; i++) {
		tp = (struct tty3270 *)
			raw3270_find_view(&tty3270_fn, i + RAW3270_FIRSTMINOR);
		if (!IS_ERR(tp))
			raw3270_del_view(&tp->view);
	}
}

struct raw3270_fn tty3270_fn = {
	.activate = tty3270_activate,
	.deactivate = tty3270_deactivate,
	.intv = (void *) tty3270_irq,
	.release = tty3270_release,
	.free = tty3270_free
};

/*
 * This routine is called whenever a 3270 tty is opened.
 */
static int
tty3270_open(struct tty_struct *tty, struct file * filp)
{
	struct tty3270 *tp;
	int i, rc;

	if (tty->count > 1)
		return 0;
	/* Check if the tty3270 is already there. */
	tp = (struct tty3270 *)
		raw3270_find_view(&tty3270_fn,
				  tty->index + RAW3270_FIRSTMINOR);
	if (!IS_ERR(tp)) {
		tty->driver_data = tp;
		tty->winsize.ws_row = tp->view.rows - 2;
		tty->winsize.ws_col = tp->view.cols;
		tty->low_latency = 0;
		tp->tty = tty;
		tp->kbd->tty = tty;
		tp->inattr = TF_INPUT;
		return 0;
	}
	if (tty3270_max_index < tty->index + 1)
		tty3270_max_index = tty->index + 1;

	/* Quick exit if there is no device for tty->index. */
	if (PTR_ERR(tp) == -ENODEV)
		return -ENODEV;

	/* Allocate tty3270 structure on first open. */
	tp = tty3270_alloc_view();
	if (IS_ERR(tp))
		return PTR_ERR(tp);

	INIT_LIST_HEAD(&tp->lines);
	INIT_LIST_HEAD(&tp->update);
	INIT_LIST_HEAD(&tp->rcl_lines);
	tp->rcl_max = 20;
	init_timer(&tp->timer);
	tasklet_init(&tp->readlet, 
		     (void (*)(unsigned long)) tty3270_read_tasklet,
		     (unsigned long) tp->read);

	rc = raw3270_add_view(&tp->view, &tty3270_fn,
			      tty->index + RAW3270_FIRSTMINOR);
	if (rc) {
		tty3270_free_view(tp);
		return rc;
	}

	rc = tty3270_alloc_screen(tp);
	if (rc) {
		raw3270_put_view(&tp->view);
		raw3270_del_view(&tp->view);
		return rc;
	}

	tp->tty = tty;
	tty->low_latency = 0;
	tty->driver_data = tp;
	tty->winsize.ws_row = tp->view.rows - 2;
	tty->winsize.ws_col = tp->view.cols;

	tty3270_create_prompt(tp);
	tty3270_create_status(tp);
	tty3270_update_status(tp);

	/* Create blank line for every line in the tty output area. */
	for (i = 0; i < tp->view.rows - 2; i++)
		tty3270_blank_line(tp);

	tp->kbd->tty = tty;
	tp->kbd->fn_handler[KVAL(K_INCRCONSOLE)] = tty3270_exit_tty;
	tp->kbd->fn_handler[KVAL(K_SCROLLBACK)] = tty3270_scroll_backward;
	tp->kbd->fn_handler[KVAL(K_SCROLLFORW)] = tty3270_scroll_forward;
	tp->kbd->fn_handler[KVAL(K_CONS)] = tty3270_rcl_backward;
	kbd_ascebc(tp->kbd, tp->view.ascebc);

	raw3270_activate_view(&tp->view);
	return 0;
}

/*
 * This routine is called when the 3270 tty is closed. We wait
 * for the remaining request to be completed. Then we clean up.
 */
static void
tty3270_close(struct tty_struct *tty, struct file * filp)
{
	struct tty3270 *tp;

	if (tty->count > 1)
		return;
	tp = (struct tty3270 *) tty->driver_data;
	if (tp) {
		tty->driver_data = 0;
		tp->tty = tp->kbd->tty = 0;
		raw3270_put_view(&tp->view);
	}
}

/*
 * We always have room.
 */
static int
tty3270_write_room(struct tty_struct *tty)
{
	return INT_MAX;
}

/*
 * Insert character into the screen at the current position with the
 * current color and highlight. This function does NOT do cursor movement.
 */
static void
tty3270_put_character(struct tty3270 *tp, char ch)
{
	struct tty3270_line *line;
	struct tty3270_cell *cell;

	line = tp->screen + tp->cy;
	if (line->len <= tp->cx) {
		while (line->len < tp->cx) {
			cell = line->cells + line->len;
			cell->character = tp->view.ascebc[' '];
			cell->highlight = tp->highlight;
			cell->f_color = tp->f_color;
			line->len++;
		}
		line->len++;
	}
	cell = line->cells + tp->cx;
	cell->character = tp->view.ascebc[(unsigned int) ch];
	cell->highlight = tp->highlight;
	cell->f_color = tp->f_color;
}

/*
 * Convert a tty3270_line to a 3270 data fragment usable for output.
 */
static void
tty3270_convert_line(struct tty3270 *tp, int line_nr)
{
	struct tty3270_line *line;
	struct tty3270_cell *cell;
	struct string *s, *n;
	unsigned char highlight;
	unsigned char f_color;
	char *cp;
	int flen, i;

	/* Determine how long the fragment will be. */
	flen = 3;		/* Prefix (TO_SBA). */
	line = tp->screen + line_nr;
	flen += line->len;
	highlight = TAX_RESET;
	f_color = TAC_RESET;
	for (i = 0, cell = line->cells; i < line->len; i++, cell++) {
		if (cell->highlight != highlight) {
			flen += 3;	/* TO_SA to switch highlight. */
			highlight = cell->highlight;
		}
		if (cell->f_color != f_color) {
			flen += 3;	/* TO_SA to switch color. */
			f_color = cell->f_color;
		}
	}
	if (highlight != TAX_RESET)
		flen += 3;	/* TO_SA to reset hightlight. */
	if (f_color != TAC_RESET)
		flen += 3;	/* TO_SA to reset color. */
	if (line->len < tp->view.cols)
		flen += 4;	/* Postfix (TO_RA). */

	/* Find the line in the list. */
	i = tp->view.rows - 2 - line_nr;
	list_for_each_entry_reverse(s, &tp->lines, list)
		if (--i <= 0)
			break;
	/*
	 * Check if the line needs to get reallocated.
	 */
	if (s->len != flen) {
		/* Reallocate string. */
		n = tty3270_alloc_string(tp, flen);
		list_add(&n->list, &s->list);
		list_del_init(&s->list);
		if (!list_empty(&s->update))
			list_del_init(&s->update);
		free_string(&tp->freemem, s);
		s = n;
	}

	/* Write 3270 data fragment. */
	cp = s->string;
	*cp++ = TO_SBA;
	*cp++ = 0;
	*cp++ = 0;

	highlight = TAX_RESET;
	f_color = TAC_RESET;
	for (i = 0, cell = line->cells; i < line->len; i++, cell++) {
		if (cell->highlight != highlight) {
			*cp++ = TO_SA;
			*cp++ = TAT_EXTHI;
			*cp++ = cell->highlight;
			highlight = cell->highlight;
		}
		if (cell->f_color != f_color) {
			*cp++ = TO_SA;
			*cp++ = TAT_COLOR;
			*cp++ = cell->f_color;
			f_color = cell->f_color;
		}
		*cp++ = cell->character;
	}
	if (highlight != TAX_RESET) {
		*cp++ = TO_SA;
		*cp++ = TAT_EXTHI;
		*cp++ = TAX_RESET;
	}
	if (f_color != TAC_RESET) {
		*cp++ = TO_SA;
		*cp++ = TAT_COLOR;
		*cp++ = TAC_RESET;
	}
	if (line->len < tp->view.cols) {
		*cp++ = TO_RA;
		*cp++ = 0;
		*cp++ = 0;
		*cp++ = 0;
	}

	if (tp->nr_up + line_nr < tp->view.rows - 2) {
		/* Line is currently visible on screen. */
		tty3270_update_string(tp, s, line_nr);
		/* Add line to update list. */
		if (list_empty(&s->update)) {
			list_add_tail(&s->update, &tp->update);
			tp->update_flags |= TTY_UPDATE_LIST;
		}
	}
}

/*
 * Do carriage return.
 */
static void
tty3270_cr(struct tty3270 *tp)
{
	tp->cx = 0;
}

/*
 * Do line feed.
 */
static void
tty3270_lf(struct tty3270 *tp)
{
	struct tty3270_line temp;
	int i;

	tty3270_convert_line(tp, tp->cy);
	if (tp->cy < tp->view.rows - 3) {
		tp->cy++;
		return;
	}
	/* Last line just filled up. Add new, blank line. */
	tty3270_blank_line(tp);
	temp = tp->screen[0];
	temp.len = 0;
	for (i = 0; i < tp->view.rows - 3; i++)
		tp->screen[i] = tp->screen[i+1];
	tp->screen[tp->view.rows - 3] = temp;
	tty3270_rebuild_update(tp);
}

static void
tty3270_ri(struct tty3270 *tp)
{
	if (tp->cy > 0) {
	    tty3270_convert_line(tp, tp->cy);
	    tp->cy--;
	}
}

/*
 * Insert characters at current position.
 */
static void
tty3270_insert_characters(struct tty3270 *tp, int n)
{
	struct tty3270_line *line;
	int k;

	line = tp->screen + tp->cy;
	while (line->len < tp->cx) {
		line->cells[line->len].character = tp->view.ascebc[' '];
		line->cells[line->len].highlight = TAX_RESET;
		line->cells[line->len].f_color = TAC_RESET;
		line->len++;
	}
	if (n > tp->view.cols - tp->cx)
		n = tp->view.cols - tp->cx;
	k = min_t(int, line->len - tp->cx, tp->view.cols - tp->cx - n);
	while (k--)
		line->cells[tp->cx + n + k] = line->cells[tp->cx + k];
	line->len += n;
	if (line->len > tp->view.cols)
		line->len = tp->view.cols;
	while (n-- > 0) {
		line->cells[tp->cx + n].character = tp->view.ascebc[' '];
		line->cells[tp->cx + n].highlight = tp->highlight;
		line->cells[tp->cx + n].f_color = tp->f_color;
	}
}

/*
 * Delete characters at current position.
 */
static void
tty3270_delete_characters(struct tty3270 *tp, int n)
{
	struct tty3270_line *line;
	int i;

	line = tp->screen + tp->cy;
	if (line->len <= tp->cx)
		return;
	if (line->len - tp->cx <= n) {
		line->len = tp->cx;
		return;
	}
	for (i = tp->cx; i + n < line->len; i++)
		line->cells[i] = line->cells[i + n];
	line->len -= n;
}

/*
 * Erase characters at current position.
 */
static void
tty3270_erase_characters(struct tty3270 *tp, int n)
{
	struct tty3270_line *line;
	struct tty3270_cell *cell;

	line = tp->screen + tp->cy;
	while (line->len > tp->cx && n-- > 0) {
		cell = line->cells + tp->cx++;
		cell->character = ' ';
		cell->highlight = TAX_RESET;
		cell->f_color = TAC_RESET;
	}
	tp->cx += n;
	tp->cx = min_t(int, tp->cx, tp->view.cols - 1);
}

/*
 * Erase line, 3 different cases:
 *  Esc [ 0 K	Erase from current position to end of line inclusive
 *  Esc [ 1 K	Erase from beginning of line to current position inclusive
 *  Esc [ 2 K	Erase entire line (without moving cursor)
 */
static void