tty: make tty_operations::write()'s count size_t

Unify with the rest of the code. Use size_t for counts and ssize_t for
retval.

Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20230810091510.13006-30-jirislaby@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

20 files changed, 37 insertions, 27 deletions

diff --git a/drivers/tty/amiserial.c b/drivers/tty/amiserial.c
index 91cf294ec8c1..785558c65ae8 100644
--- a/drivers/tty/amiserial.c
+++ b/drivers/tty/amiserial.c
@@ -741,7 +741,7 @@ static void rs_flush_chars(struct tty_struct *tty)
 	local_irq_restore(flags);
 }
 
-static int rs_write(struct tty_struct * tty, const u8 *buf, int count)
+static ssize_t rs_write(struct tty_struct * tty, const u8 *buf, size_t count)
 {
 	int	c, ret = 0;
 	struct serial_state *info = tty->driver_data;
diff --git a/drivers/tty/ehv_bytechan.c b/drivers/tty/ehv_bytechan.c
index de36347e2145..a067628e01c8 100644
--- a/drivers/tty/ehv_bytechan.c
+++ b/drivers/tty/ehv_bytechan.c
@@ -466,7 +466,8 @@ static irqreturn_t ehv_bc_tty_tx_isr(int irq, void *data)
  * ehv_bc_tty_write_room() will never lie, so the tty layer will never send us
  * too much data.
  */
-static int ehv_bc_tty_write(struct tty_struct *ttys, const u8 *s, int count)
+static ssize_t ehv_bc_tty_write(struct tty_struct *ttys, const u8 *s,
+				size_t count)
 {
 	struct ehv_bc_data *bc = ttys->driver_data;
 	unsigned long flags;
diff --git a/drivers/tty/goldfish.c b/drivers/tty/goldfish.c
index faa597ffbaf9..4591f940b7a1 100644
--- a/drivers/tty/goldfish.c
+++ b/drivers/tty/goldfish.c
@@ -185,7 +185,8 @@ static void goldfish_tty_hangup(struct tty_struct *tty)
 	tty_port_hangup(tty->port);
 }
 
-static int goldfish_tty_write(struct tty_struct *tty, const u8 *buf, int count)
+static ssize_t goldfish_tty_write(struct tty_struct *tty, const u8 *buf,
+				  size_t count)
 {
 	goldfish_tty_do_write(tty->index, buf, count);
 	return count;
diff --git a/drivers/tty/hvc/hvc_console.c b/drivers/tty/hvc/hvc_console.c
index 4c60d15c7a6f..e93e8072ec86 100644
--- a/drivers/tty/hvc/hvc_console.c
+++ b/drivers/tty/hvc/hvc_console.c
@@ -496,7 +496,7 @@ static int hvc_push(struct hvc_struct *hp)
 	return n;
 }
 
-static int hvc_write(struct tty_struct *tty, const u8 *buf, int count)
+static ssize_t hvc_write(struct tty_struct *tty, const u8 *buf, size_t count)
 {
 	struct hvc_struct *hp = tty->driver_data;
 	unsigned long flags;
diff --git a/drivers/tty/hvc/hvcs.c b/drivers/tty/hvc/hvcs.c
index 2465d61b4e76..1de91fa23b04 100644
--- a/drivers/tty/hvc/hvcs.c
+++ b/drivers/tty/hvc/hvcs.c
@@ -1257,7 +1257,7 @@ static void hvcs_hangup(struct tty_struct * tty)
  * tty_hangup will allow hvcs_write time to complete execution before it
  * terminates our device.
  */
-static int hvcs_write(struct tty_struct *tty, const u8 *buf, int count)
+static ssize_t hvcs_write(struct tty_struct *tty, const u8 *buf, size_t count)
 {
 	struct hvcs_struct *hvcsd = tty->driver_data;
 	unsigned int unit_address;
@@ -1299,7 +1299,8 @@ static int hvcs_write(struct tty_struct *tty, const u8 *buf, int count)
 	unit_address = hvcsd->vdev->unit_address;
 
 	while (count > 0) {
-		tosend = min(count, (HVCS_BUFF_LEN - hvcsd->chars_in_buffer));
+		tosend = min_t(unsigned, count,
+			       (HVCS_BUFF_LEN - hvcsd->chars_in_buffer));
 		/*
 		 * No more space, this probably means that the last call to
 		 * hvcs_write() didn't succeed and the buffer was filled up.
diff --git a/drivers/tty/hvc/hvsi.c b/drivers/tty/hvc/hvsi.c
index 46dd62df2442..c57bd85aa488 100644
--- a/drivers/tty/hvc/hvsi.c
+++ b/drivers/tty/hvc/hvsi.c
@@ -904,7 +904,8 @@ static unsigned int hvsi_chars_in_buffer(struct tty_struct *tty)
 	return hp->n_outbuf;
 }
 
-static int hvsi_write(struct tty_struct *tty, const u8 *source, int count)
+static ssize_t hvsi_write(struct tty_struct *tty, const u8 *source,
+			  size_t count)
 {
 	struct hvsi_struct *hp = tty->driver_data;
 	unsigned long flags;
diff --git a/drivers/tty/ipwireless/tty.c b/drivers/tty/ipwireless/tty.c
index cd43208c523c..b6de40815fb9 100644
--- a/drivers/tty/ipwireless/tty.c
+++ b/drivers/tty/ipwireless/tty.c
@@ -186,7 +186,8 @@ static void ipw_write_packet_sent_callback(void *callback_data,
 	tty->tx_bytes_queued -= packet_length;
 }
 
-static int ipw_write(struct tty_struct *linux_tty, const u8 *buf, int count)
+static ssize_t ipw_write(struct tty_struct *linux_tty, const u8 *buf,
+			 size_t count)
 {
 	struct ipw_tty *tty = linux_tty->driver_data;
 	int room, ret;
diff --git a/drivers/tty/mips_ejtag_fdc.c b/drivers/tty/mips_ejtag_fdc.c
index cf4ef0c38624..369ec71c24ef 100644
--- a/drivers/tty/mips_ejtag_fdc.c
+++ b/drivers/tty/mips_ejtag_fdc.c
@@ -796,8 +796,8 @@ static void mips_ejtag_fdc_tty_hangup(struct tty_struct *tty)
 	tty_port_hangup(tty->port);
 }
 
-static int mips_ejtag_fdc_tty_write(struct tty_struct *tty, const u8 *buf,
-				    int total)
+static ssize_t mips_ejtag_fdc_tty_write(struct tty_struct *tty, const u8 *buf,
+					size_t total)
 {
 	int count, block;
 	struct mips_ejtag_fdc_tty_port *dport = tty->driver_data;
@@ -816,7 +816,7 @@ static int mips_ejtag_fdc_tty_write(struct tty_struct *tty, const u8 *buf,
 	 */
 	spin_lock(&dport->xmit_lock);
 	/* Work out how many bytes we can write to the xmit buffer */
-	total = min(total, (int)(priv->xmit_size - dport->xmit_cnt));
+	total = min_t(size_t, total, priv->xmit_size - dport->xmit_cnt);
 	atomic_add(total, &priv->xmit_total);
 	dport->xmit_cnt += total;
 	/* Write the actual bytes (may need splitting if it wraps) */
diff --git a/drivers/tty/moxa.c b/drivers/tty/moxa.c
index d94cf1be651b..bf3f87ba3a92 100644
--- a/drivers/tty/moxa.c
+++ b/drivers/tty/moxa.c
@@ -487,7 +487,7 @@ module_param(ttymajor, int, 0);
  */
 static int moxa_open(struct tty_struct *, struct file *);
 static void moxa_close(struct tty_struct *, struct file *);
-static int moxa_write(struct tty_struct *, const u8 *, int);
+static ssize_t moxa_write(struct tty_struct *, const u8 *, size_t);
 static unsigned int moxa_write_room(struct tty_struct *);
 static void moxa_flush_buffer(struct tty_struct *);
 static unsigned int moxa_chars_in_buffer(struct tty_struct *);
@@ -1499,7 +1499,7 @@ static void moxa_close(struct tty_struct *tty, struct file *filp)
 	tty_port_close(&ch->port, tty, filp);
 }
 
-static int moxa_write(struct tty_struct *tty, const u8 *buf, int count)
+static ssize_t moxa_write(struct tty_struct *tty, const u8 *buf, size_t count)
 {
 	struct moxa_port *ch = tty->driver_data;
 	unsigned long flags;
diff --git a/drivers/tty/mxser.c b/drivers/tty/mxser.c
index a5dfd08d4ea2..10aa4ed38793 100644
--- a/drivers/tty/mxser.c
+++ b/drivers/tty/mxser.c
@@ -901,7 +901,7 @@ static void mxser_close(struct tty_struct *tty, struct file *filp)
 	tty_port_close(tty->port, tty, filp);
 }
 
-static int mxser_write(struct tty_struct *tty, const u8 *buf, int count)
+static ssize_t mxser_write(struct tty_struct *tty, const u8 *buf, size_t count)
 {
 	struct mxser_port *info = tty->driver_data;
 	unsigned long flags;
diff --git a/drivers/tty/n_gsm.c b/drivers/tty/n_gsm.c
index d167e36873fe..3e5cc30941a7 100644
--- a/drivers/tty/n_gsm.c
+++ b/drivers/tty/n_gsm.c
@@ -4256,7 +4256,7 @@ static void gsmtty_hangup(struct tty_struct *tty)
 	gsm_dlci_begin_close(dlci);
 }
 
-static int gsmtty_write(struct tty_struct *tty, const u8 *buf, int len)
+static ssize_t gsmtty_write(struct tty_struct *tty, const u8 *buf, size_t len)
 {
 	int sent;
 	struct gsm_dlci *dlci = tty->driver_data;
diff --git a/drivers/tty/nozomi.c b/drivers/tty/nozomi.c
index b3756402f5d9..02cd40147b3a 100644
--- a/drivers/tty/nozomi.c
+++ b/drivers/tty/nozomi.c
@@ -1599,7 +1599,8 @@ static void ntty_hangup(struct tty_struct *tty)
  * called when the userspace process writes to the tty (/dev/noz*).
  * Data is inserted into a fifo, which is then read and transferred to the modem.
  */
-static int ntty_write(struct tty_struct *tty, const u8 *buffer, int count)
+static ssize_t ntty_write(struct tty_struct *tty, const u8 *buffer,
+			  size_t count)
 {
 	int rval = -EINVAL;
 	struct nozomi *dc = get_dc_by_tty(tty);
diff --git a/drivers/tty/pty.c b/drivers/tty/pty.c
index 335f5744f320..df08f13052ff 100644
--- a/drivers/tty/pty.c
+++ b/drivers/tty/pty.c
@@ -108,7 +108,7 @@ static void pty_unthrottle(struct tty_struct *tty)
  *	the other side of the pty/tty pair.
  */
 
-static int pty_write(struct tty_struct *tty, const u8 *buf, int c)
+static ssize_t pty_write(struct tty_struct *tty, const u8 *buf, size_t c)
 {
 	struct tty_struct *to = tty->link;
 
diff --git a/drivers/tty/rpmsg_tty.c b/drivers/tty/rpmsg_tty.c
index 29db413bbc03..60a2915f5cfe 100644
--- a/drivers/tty/rpmsg_tty.c
+++ b/drivers/tty/rpmsg_tty.c
@@ -73,7 +73,8 @@ static void rpmsg_tty_close(struct tty_struct *tty, struct file *filp)
 	return tty_port_close(tty->port, tty, filp);
 }
 
-static int rpmsg_tty_write(struct tty_struct *tty, const u8 *buf, int len)
+static ssize_t rpmsg_tty_write(struct tty_struct *tty, const u8 *buf,
+			       size_t len)
 {
 	struct rpmsg_tty_port *cport = tty->driver_data;
 	struct rpmsg_device *rpdev;
@@ -86,7 +87,7 @@ static int rpmsg_tty_write(struct tty_struct *tty, const u8 *buf, int len)
 	if (msg_max_size < 0)
 		return msg_max_size;
 
-	msg_size = min(len, msg_max_size);
+	msg_size = min_t(unsigned int, len, msg_max_size);
 
 	/*
 	 * Use rpmsg_trysend instead of rpmsg_send to send the message so the caller is not
diff --git a/drivers/tty/serial/kgdb_nmi.c b/drivers/tty/serial/kgdb_nmi.c
index 2a04d19d5ec0..e93850f6447a 100644
--- a/drivers/tty/serial/kgdb_nmi.c
+++ b/drivers/tty/serial/kgdb_nmi.c
@@ -304,7 +304,8 @@ static unsigned int kgdb_nmi_tty_write_room(struct tty_struct *tty)
 	return 2048;
 }
 
-static int kgdb_nmi_tty_write(struct tty_struct *tty, const u8 *buf, int c)
+static ssize_t kgdb_nmi_tty_write(struct tty_struct *tty, const u8 *buf,
+				  size_t c)
 {
 	int i;
 
diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c
index d5b682ff20b3..7bdc21d5e13b 100644
--- a/drivers/tty/serial/serial_core.c
+++ b/drivers/tty/serial/serial_core.c
@@ -580,7 +580,7 @@ static void uart_flush_chars(struct tty_struct *tty)
 	uart_start(tty);
 }
 
-static int uart_write(struct tty_struct *tty, const u8 *buf, int count)
+static ssize_t uart_write(struct tty_struct *tty, const u8 *buf, size_t count)
 {
 	struct uart_state *state = tty->driver_data;
 	struct uart_port *port;
diff --git a/drivers/tty/synclink_gt.c b/drivers/tty/synclink_gt.c
index 0264e9f7699c..8112d9d5a0d8 100644
--- a/drivers/tty/synclink_gt.c
+++ b/drivers/tty/synclink_gt.c
@@ -745,7 +745,7 @@ static void update_tx_timer(struct slgt_info *info)
 	}
 }
 
-static int write(struct tty_struct *tty, const u8 *buf, int count)
+static ssize_t write(struct tty_struct *tty, const u8 *buf, size_t count)
 {
 	int ret = 0;
 	struct slgt_info *info = tty->driver_data;
@@ -754,7 +754,7 @@ static int write(struct tty_struct *tty, const u8 *buf, int count)
 	if (sanity_check(info, tty->name, "write"))
 		return -EIO;
 
-	DBGINFO(("%s write count=%d\n", info->device_name, count));
+	DBGINFO(("%s write count=%zu\n", info->device_name, count));
 
 	if (!info->tx_buf || (count > info->max_frame_size))
 		return -EIO;
diff --git a/drivers/tty/ttynull.c b/drivers/tty/ttynull.c
index 6b74ebaa0f2d..e4c4273993bc 100644
--- a/drivers/tty/ttynull.c
+++ b/drivers/tty/ttynull.c
@@ -29,7 +29,8 @@ static void ttynull_hangup(struct tty_struct *tty)
 	tty_port_hangup(&ttynull_port);
 }
 
-static int ttynull_write(struct tty_struct *tty, const u8 *buf, int count)
+static ssize_t ttynull_write(struct tty_struct *tty, const u8 *buf,
+			     size_t count)
 {
 	return count;
 }
diff --git a/drivers/tty/vcc.c b/drivers/tty/vcc.c
index c223879039b8..9cc569174c83 100644
--- a/drivers/tty/vcc.c
+++ b/drivers/tty/vcc.c
@@ -804,7 +804,7 @@ static void vcc_hangup(struct tty_struct *tty)
 	tty_port_hangup(tty->port);
 }
 
-static int vcc_write(struct tty_struct *tty, const u8 *buf, int count)
+static ssize_t vcc_write(struct tty_struct *tty, const u8 *buf, size_t count)
 {
 	struct vcc_port *port;
 	struct vio_vcc *pkt;
@@ -826,7 +826,8 @@ static int vcc_write(struct tty_struct *tty, const u8 *buf, int count)
 
 	while (count > 0) {
 		/* Minimum of data to write and space available */
-		tosend = min(count, (VCC_BUFF_LEN - port->chars_in_buffer));
+		tosend = min_t(size_t, count,
+			       (VCC_BUFF_LEN - port->chars_in_buffer));
 
 		if (!tosend)
 			break;
diff --git a/drivers/tty/vt/vt.c b/drivers/tty/vt/vt.c
index ea7c20d66acb..5c47f77804f0 100644
--- a/drivers/tty/vt/vt.c
+++ b/drivers/tty/vt/vt.c
@@ -3238,7 +3238,7 @@ int tioclinux(struct tty_struct *tty, unsigned long arg)
  * /dev/ttyN handling
  */
 
-static int con_write(struct tty_struct *tty, const u8 *buf, int count)
+static ssize_t con_write(struct tty_struct *tty, const u8 *buf, size_t count)
 {
 	int	retval;