um: switch users of ->chan_list to ->chan_{in,out} (easy cases)

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>

5 files changed, 88 insertions, 128 deletions

diff --git a/arch/um/drivers/chan.h b/arch/um/drivers/chan.h
index 8df0fd9024d..5078ec701c6 100644
--- a/arch/um/drivers/chan.h
+++ b/arch/um/drivers/chan.h
@@ -27,24 +27,24 @@ struct chan {
 	void *data;
 };
 
-extern void chan_interrupt(struct list_head *chans, struct delayed_work *task,
+extern void chan_interrupt(struct line *line, struct delayed_work *task,
 			   struct tty_struct *tty, int irq);
 extern int parse_chan_pair(char *str, struct line *line, int device,
 			   const struct chan_opts *opts, char **error_out);
-extern int write_chan(struct list_head *chans, const char *buf, int len,
+extern int write_chan(struct chan *chan, const char *buf, int len,
 			     int write_irq);
-extern int console_write_chan(struct list_head *chans, const char *buf, 
+extern int console_write_chan(struct chan *chan, const char *buf, 
 			      int len);
 extern int console_open_chan(struct line *line, struct console *co);
-extern void deactivate_chan(struct list_head *chans, int irq);
-extern void reactivate_chan(struct list_head *chans, int irq);
-extern void chan_enable_winch(struct list_head *chans, struct tty_struct *tty);
+extern void deactivate_chan(struct chan *chan, int irq);
+extern void reactivate_chan(struct chan *chan, int irq);
+extern void chan_enable_winch(struct chan *chan, struct tty_struct *tty);
 extern int enable_chan(struct line *line);
 extern void close_chan(struct list_head *chans, int delay_free_irq);
-extern int chan_window_size(struct list_head *chans, 
+extern int chan_window_size(struct line *line, 
 			     unsigned short *rows_out, 
 			     unsigned short *cols_out);
-extern int chan_config_string(struct list_head *chans, char *str, int size,
+extern int chan_config_string(struct line *line, char *str, int size,
 			      char **error_out);
 
 #endif
diff --git a/arch/um/drivers/chan_kern.c b/arch/um/drivers/chan_kern.c
index 390920d63a2..73d7bc018ab 100644
--- a/arch/um/drivers/chan_kern.c
+++ b/arch/um/drivers/chan_kern.c
@@ -140,18 +140,10 @@ static int open_chan(struct list_head *chans)
 	return err;
 }
 
-void chan_enable_winch(struct list_head *chans, struct tty_struct *tty)
+void chan_enable_winch(struct chan *chan, struct tty_struct *tty)
 {
-	struct list_head *ele;
-	struct chan *chan;
-
-	list_for_each(ele, chans) {
-		chan = list_entry(ele, struct chan, list);
-		if (chan->primary && chan->output && chan->ops->winch) {
-			register_winch(chan->fd, tty);
-			return;
-		}
-	}
+	if (chan && chan->primary && chan->ops->winch)
+		register_winch(chan->fd, tty);
 }
 
 int enable_chan(struct line *line)
@@ -258,72 +250,45 @@ void close_chan(struct list_head *chans, int delay_free_irq)
 	}
 }
 
-void deactivate_chan(struct list_head *chans, int irq)
+void deactivate_chan(struct chan *chan, int irq)
 {
-	struct list_head *ele;
-
-	struct chan *chan;
-	list_for_each(ele, chans) {
-		chan = list_entry(ele, struct chan, list);
-
-		if (chan->enabled && chan->input)
-			deactivate_fd(chan->fd, irq);
-	}
+	if (chan && chan->enabled)
+		deactivate_fd(chan->fd, irq);
 }
 
-void reactivate_chan(struct list_head *chans, int irq)
+void reactivate_chan(struct chan *chan, int irq)
 {
-	struct list_head *ele;
-	struct chan *chan;
-
-	list_for_each(ele, chans) {
-		chan = list_entry(ele, struct chan, list);
-
-		if (chan->enabled && chan->input)
-			reactivate_fd(chan->fd, irq);
-	}
+	if (chan && chan->enabled)
+		reactivate_fd(chan->fd, irq);
 }
 
-int write_chan(struct list_head *chans, const char *buf, int len,
+int write_chan(struct chan *chan, const char *buf, int len,
 	       int write_irq)
 {
-	struct list_head *ele;
-	struct chan *chan = NULL;
 	int n, ret = 0;
 
-	if (len == 0)
+	if (len == 0 || !chan || !chan->ops->write)
 		return 0;
 
-	list_for_each(ele, chans) {
-		chan = list_entry(ele, struct chan, list);
-		if (!chan->output || (chan->ops->write == NULL))
-			continue;
-
-		n = chan->ops->write(chan->fd, buf, len, chan->data);
-		if (chan->primary) {
-			ret = n;
-			if ((ret == -EAGAIN) || ((ret >= 0) && (ret < len)))
-				reactivate_fd(chan->fd, write_irq);
-		}
+	n = chan->ops->write(chan->fd, buf, len, chan->data);
+	if (chan->primary) {
+		ret = n;
+		if ((ret == -EAGAIN) || ((ret >= 0) && (ret < len)))
+			reactivate_fd(chan->fd, write_irq);
 	}
 	return ret;
 }
 
-int console_write_chan(struct list_head *chans, const char *buf, int len)
+int console_write_chan(struct chan *chan, const char *buf, int len)
 {
-	struct list_head *ele;
-	struct chan *chan;
 	int n, ret = 0;
 
-	list_for_each(ele, chans) {
-		chan = list_entry(ele, struct chan, list);
-		if (!chan->output || (chan->ops->console_write == NULL))
-			continue;
+	if (!chan || !chan->ops->console_write)
+		return 0;
 
-		n = chan->ops->console_write(chan->fd, buf, len);
-		if (chan->primary)
-			ret = n;
-	}
+	n = chan->ops->console_write(chan->fd, buf, len);
+	if (chan->primary)
+		ret = n;
 	return ret;
 }
 
@@ -340,20 +305,24 @@ int console_open_chan(struct line *line, struct console *co)
 	return 0;
 }
 
-int chan_window_size(struct list_head *chans, unsigned short *rows_out,
+int chan_window_size(struct line *line, unsigned short *rows_out,
 		      unsigned short *cols_out)
 {
-	struct list_head *ele;
 	struct chan *chan;
 
-	list_for_each(ele, chans) {
-		chan = list_entry(ele, struct chan, list);
-		if (chan->primary) {
-			if (chan->ops->window_size == NULL)
-				return 0;
-			return chan->ops->window_size(chan->fd, chan->data,
-						      rows_out, cols_out);
-		}
+	chan = line->chan_in;
+	if (chan && chan->primary) {
+		if (chan->ops->window_size == NULL)
+			return 0;
+		return chan->ops->window_size(chan->fd, chan->data,
+					      rows_out, cols_out);
+	}
+	chan = line->chan_out;
+	if (chan && chan->primary) {
+		if (chan->ops->window_size == NULL)
+			return 0;
+		return chan->ops->window_size(chan->fd, chan->data,
+					      rows_out, cols_out);
 	}
 	return 0;
 }
@@ -429,21 +398,15 @@ static int chan_pair_config_string(struct chan *in, struct chan *out,
 	return n;
 }
 
-int chan_config_string(struct list_head *chans, char *str, int size,
+int chan_config_string(struct line *line, char *str, int size,
 		       char **error_out)
 {
-	struct list_head *ele;
-	struct chan *chan, *in = NULL, *out = NULL;
+	struct chan *in = line->chan_in, *out = line->chan_out;
 
-	list_for_each(ele, chans) {
-		chan = list_entry(ele, struct chan, list);
-		if (!chan->primary)
-			continue;
-		if (chan->input)
-			in = chan;
-		if (chan->output)
-			out = chan;
-	}
+	if (in && !in->primary)
+		in = NULL;
+	if (out && !out->primary)
+		out = NULL;
 
 	return chan_pair_config_string(in, out, str, size, error_out);
 }
@@ -589,39 +552,36 @@ int parse_chan_pair(char *str, struct line *line, int device,
 	return 0;
 }
 
-void chan_interrupt(struct list_head *chans, struct delayed_work *task,
+void chan_interrupt(struct line *line, struct delayed_work *task,
 		    struct tty_struct *tty, int irq)
 {
-	struct list_head *ele, *next;
-	struct chan *chan;
+	struct chan *chan = line->chan_in;
 	int err;
 	char c;
 
-	list_for_each_safe(ele, next, chans) {
-		chan = list_entry(ele, struct chan, list);
-		if (!chan->input || (chan->ops->read == NULL))
-			continue;
-		do {
-			if (tty && !tty_buffer_request_room(tty, 1)) {
-				schedule_delayed_work(task, 1);
-				goto out;
-			}
-			err = chan->ops->read(chan->fd, &c, chan->data);
-			if (err > 0)
-				tty_receive_char(tty, c);
-		} while (err > 0);
-
-		if (err == 0)
-			reactivate_fd(chan->fd, irq);
-		if (err == -EIO) {
-			if (chan->primary) {
-				if (tty != NULL)
-					tty_hangup(tty);
-				close_chan(chans, 1);
-				return;
-			}
-			else close_one_chan(chan, 1);
+	if (!chan || !chan->ops->read)
+		goto out;
+
+	do {
+		if (tty && !tty_buffer_request_room(tty, 1)) {
+			schedule_delayed_work(task, 1);
+			goto out;
+		}
+		err = chan->ops->read(chan->fd, &c, chan->data);
+		if (err > 0)
+			tty_receive_char(tty, c);
+	} while (err > 0);
+
+	if (err == 0)
+		reactivate_fd(chan->fd, irq);
+	if (err == -EIO) {
+		if (chan->primary) {
+			if (tty != NULL)
+				tty_hangup(tty);
+			close_chan(&line->chan_list, 1);
+			return;
 		}
+		else close_one_chan(chan, 1);
 	}
  out:
 	if (tty)
diff --git a/arch/um/drivers/line.c b/arch/um/drivers/line.c
index 9ffade87a8c..c1aa89cefae 100644
--- a/arch/um/drivers/line.c
+++ b/arch/um/drivers/line.c
@@ -21,7 +21,7 @@ static irqreturn_t line_interrupt(int irq, void *data)
 	struct line *line = chan->line;
 
 	if (line)
-		chan_interrupt(&line->chan_list, &line->task, line->tty, irq);
+		chan_interrupt(line, &line->task, line->tty, irq);
 	return IRQ_HANDLED;
 }
 
@@ -30,7 +30,7 @@ static void line_timer_cb(struct work_struct *work)
 	struct line *line = container_of(work, struct line, task.work);
 
 	if (!line->throttled)
-		chan_interrupt(&line->chan_list, &line->task, line->tty,
+		chan_interrupt(line, &line->task, line->tty,
 			       line->driver->read_irq);
 }
 
@@ -145,7 +145,7 @@ static int flush_buffer(struct line *line)
 		/* line->buffer + LINE_BUFSIZE is the end of the buffer! */
 		count = line->buffer + LINE_BUFSIZE - line->head;
 
-		n = write_chan(&line->chan_list, line->head, count,
+		n = write_chan(line->chan_out, line->head, count,
 			       line->driver->write_irq);
 		if (n < 0)
 			return n;
@@ -162,7 +162,7 @@ static int flush_buffer(struct line *line)
 	}
 
 	count = line->tail - line->head;
-	n = write_chan(&line->chan_list, line->head, count,
+	n = write_chan(line->chan_out, line->head, count,
 		       line->driver->write_irq);
 
 	if (n < 0)
@@ -206,7 +206,7 @@ int line_write(struct tty_struct *tty, const unsigned char *buf, int len)
 	if (line->head != line->tail)
 		ret = buffer_data(line, buf, len);
 	else {
-		n = write_chan(&line->chan_list, buf, len,
+		n = write_chan(line->chan_out, buf, len,
 			       line->driver->write_irq);
 		if (n < 0) {
 			ret = n;
@@ -318,7 +318,7 @@ void line_throttle(struct tty_struct *tty)
 {
 	struct line *line = tty->driver_data;
 
-	deactivate_chan(&line->chan_list, line->driver->read_irq);
+	deactivate_chan(line->chan_in, line->driver->read_irq);
 	line->throttled = 1;
 }
 
@@ -327,7 +327,7 @@ void line_unthrottle(struct tty_struct *tty)
 	struct line *line = tty->driver_data;
 
 	line->throttled = 0;
-	chan_interrupt(&line->chan_list, &line->task, tty,
+	chan_interrupt(line, &line->task, tty,
 		       line->driver->read_irq);
 
 	/*
@@ -336,7 +336,7 @@ void line_unthrottle(struct tty_struct *tty)
 	 * again and we shouldn't turn the interrupt back on.
 	 */
 	if (!line->throttled)
-		reactivate_chan(&line->chan_list, line->driver->read_irq);
+		reactivate_chan(line->chan_in, line->driver->read_irq);
 }
 
 static irqreturn_t line_write_interrupt(int irq, void *data)
@@ -428,11 +428,11 @@ int line_open(struct line *lines, struct tty_struct *tty)
 	INIT_DELAYED_WORK(&line->task, line_timer_cb);
 
 	if (!line->sigio) {
-		chan_enable_winch(&line->chan_list, tty);
+		chan_enable_winch(line->chan_out, tty);
 		line->sigio = 1;
 	}
 
-	chan_window_size(&line->chan_list, &tty->winsize.ws_row,
+	chan_window_size(line, &tty->winsize.ws_row,
 			 &tty->winsize.ws_col);
 out_unlock:
 	mutex_unlock(&line->count_lock);
@@ -624,7 +624,7 @@ int line_get_config(char *name, struct line *lines, unsigned int num, char *str,
 		CONFIG_CHUNK(str, size, n, "none", 1);
 	else if (line->tty == NULL)
 		CONFIG_CHUNK(str, size, n, line->init_str, 1);
-	else n = chan_config_string(&line->chan_list, str, size, error_out);
+	else n = chan_config_string(line, str, size, error_out);
 	mutex_unlock(&line->count_lock);
 
 	return n;
@@ -761,7 +761,7 @@ static irqreturn_t winch_interrupt(int irq, void *data)
 	if (tty != NULL) {
 		line = tty->driver_data;
 		if (line != NULL) {
-			chan_window_size(&line->chan_list, &tty->winsize.ws_row,
+			chan_window_size(line, &tty->winsize.ws_row,
 					 &tty->winsize.ws_col);
 			kill_pgrp(tty->pgrp, SIGWINCH, 1);
 		}
diff --git a/arch/um/drivers/ssl.c b/arch/um/drivers/ssl.c
index d0b5ccf2379..e09801a1327 100644
--- a/arch/um/drivers/ssl.c
+++ b/arch/um/drivers/ssl.c
@@ -151,7 +151,7 @@ static void ssl_console_write(struct console *c, const char *string,
 	unsigned long flags;
 
 	spin_lock_irqsave(&line->lock, flags);
-	console_write_chan(&line->chan_list, string, len);
+	console_write_chan(line->chan_out, string, len);
 	spin_unlock_irqrestore(&line->lock, flags);
 }
 
diff --git a/arch/um/drivers/stdio_console.c b/arch/um/drivers/stdio_console.c
index fe581209d62..7663541c372 100644
--- a/arch/um/drivers/stdio_console.c
+++ b/arch/um/drivers/stdio_console.c
@@ -124,7 +124,7 @@ static void uml_console_write(struct console *console, const char *string,
 	unsigned long flags;
 
 	spin_lock_irqsave(&line->lock, flags);
-	console_write_chan(&line->chan_list, string, len);
+	console_write_chan(line->chan_out, string, len);
 	spin_unlock_irqrestore(&line->lock, flags);
 }