tty: um: convert to u8/__u8 and size_t

Switch character types to u8 and sizes to size_t. To conform to
characters/sizes in the rest of the tty layer.

Note we use __u8 in the userspace files.

Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: linux-um@lists.infradead.org
Link: https://lore.kernel.org/r/20231206073712.17776-27-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

arch/um/drivers/chan.h

@@ -30,7 +30,7 @@ struct chan {
 extern void chan_interrupt(struct line *line, 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 chan *chan, const char *buf, int len,
+extern int write_chan(struct chan *chan, const u8 *buf, size_t len,
 			     int write_irq);
 extern int console_write_chan(struct chan *chan, const char *buf, 
 			      int len);

arch/um/drivers/chan_kern.c

@@ -33,14 +33,14 @@ static void not_configged_close(int fd, void *data)
 	       "UML\n");
 }
 
-static int not_configged_read(int fd, char *c_out, void *data)
+static int not_configged_read(int fd, u8 *c_out, void *data)
 {
 	printk(KERN_ERR "Using a channel type which is configured out of "
 	       "UML\n");
 	return -EIO;
 }
 
-static int not_configged_write(int fd, const char *buf, int len, void *data)
+static int not_configged_write(int fd, const u8 *buf, size_t len, void *data)
 {
 	printk(KERN_ERR "Using a channel type which is configured out of "
 	       "UML\n");
@@ -247,8 +247,7 @@ void deactivate_chan(struct chan *chan, int irq)
 		deactivate_fd(chan->fd, irq);
 }
 
-int write_chan(struct chan *chan, const char *buf, int len,
-	       int write_irq)
+int write_chan(struct chan *chan, const u8 *buf, size_t len, int write_irq)
 {
 	int n, ret = 0;
 
@@ -540,7 +539,7 @@ void chan_interrupt(struct line *line, int irq)
 	struct tty_port *port = &line->port;
 	struct chan *chan = line->chan_in;
 	int err;
-	char c;
+	u8 c;
 
 	if (!chan || !chan->ops->read)
 		goto out;

arch/um/drivers/chan_user.c

@@ -19,7 +19,7 @@ void generic_close(int fd, void *unused)
 	close(fd);
 }
 
-int generic_read(int fd, char *c_out, void *unused)
+int generic_read(int fd, __u8 *c_out, void *unused)
 {
 	int n;
 
@@ -35,7 +35,7 @@ int generic_read(int fd, char *c_out, void *unused)
 
 /* XXX Trivial wrapper around write */
 
-int generic_write(int fd, const char *buf, int n, void *unused)
+int generic_write(int fd, const __u8 *buf, size_t n, void *unused)
 {
 	int err;
 

arch/um/drivers/chan_user.h

@@ -7,6 +7,7 @@
 #define __CHAN_USER_H__
 
 #include <init.h>
+#include <linux/types.h>
 
 struct chan_opts {
 	void (*const announce)(char *dev_name, int dev);
@@ -19,8 +20,8 @@ struct chan_ops {
 	void *(*init)(char *, int, const struct chan_opts *);
 	int (*open)(int, int, int, void *, char **);
 	void (*close)(int, void *);
-	int (*read)(int, char *, void *);
-	int (*write)(int, const char *, int, void *);
+	int (*read)(int, __u8 *, void *);
+	int (*write)(int, const __u8 *, size_t, void *);
 	int (*console_write)(int, const char *, int);
 	int (*window_size)(int, void *, unsigned short *, unsigned short *);
 	void (*free)(void *);
@@ -31,8 +32,8 @@ extern const struct chan_ops fd_ops, null_ops, port_ops, pts_ops, pty_ops,
 	tty_ops, xterm_ops;
 
 extern void generic_close(int fd, void *unused);
-extern int generic_read(int fd, char *c_out, void *unused);
-extern int generic_write(int fd, const char *buf, int n, void *unused);
+extern int generic_read(int fd, __u8 *c_out, void *unused);
+extern int generic_write(int fd, const __u8 *buf, size_t n, void *unused);
 extern int generic_console_write(int fd, const char *buf, int n);
 extern int generic_window_size(int fd, void *unused, unsigned short *rows_out,
 			       unsigned short *cols_out);

arch/um/drivers/line.c

@@ -83,7 +83,7 @@ unsigned int line_chars_in_buffer(struct tty_struct *tty)
  *
  * Must be called while holding line->lock!
  */
-static int buffer_data(struct line *line, const char *buf, int len)
+static int buffer_data(struct line *line, const u8 *buf, size_t len)
 {
 	int end, room;
 

arch/um/drivers/line.h

@@ -47,9 +47,9 @@ struct line {
 	 *
 	 * buffer points to a buffer allocated on demand, of length
 	 * LINE_BUFSIZE, head to the start of the ring, tail to the end.*/
-	char *buffer;
-	char *head;
-	char *tail;
+	u8 *buffer;
+	u8 *head;
+	u8 *tail;
 
 	int sigio;
 	struct delayed_work task;

arch/um/drivers/null.c

@@ -28,7 +28,7 @@ static int null_open(int input, int output, int primary, void *d,
 	return (fd < 0) ? -errno : fd;
 }
 
-static int null_read(int fd, char *c_out, void *unused)
+static int null_read(int fd, __u8 *c_out, void *unused)
 {
 	return -ENODEV;
 }