Adding upstream version 6.8.9.upstream/6.8.9

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

12 files changed, 129 insertions, 93 deletions

diff --git a/drivers/tty/hvc/Kconfig b/drivers/tty/hvc/Kconfig
index 4f9264d00..c2a4e88b3 100644
--- a/drivers/tty/hvc/Kconfig
+++ b/drivers/tty/hvc/Kconfig
@@ -108,13 +108,15 @@ config HVC_DCC_SERIALIZE_SMP
 
 config HVC_RISCV_SBI
 	bool "RISC-V SBI console support"
-	depends on RISCV_SBI_V01
+	depends on RISCV_SBI && NONPORTABLE
 	select HVC_DRIVER
 	help
 	  This enables support for console output via RISC-V SBI calls, which
-	  is normally used only during boot to output printk.
+	  is normally used only during boot to output printk.  This driver
+	  conflicts with real console drivers and should not be enabled on
+	  systems that directly access the console.
 
-	  If you don't know what do to here, say Y.
+	  If you don't know what do to here, say N.
 
 config HVCS
 	tristate "IBM Hypervisor Virtual Console Server support"
diff --git a/drivers/tty/hvc/hvc_console.c b/drivers/tty/hvc/hvc_console.c
index 959fae54c..cd1f657f7 100644
--- a/drivers/tty/hvc/hvc_console.c
+++ b/drivers/tty/hvc/hvc_console.c
@@ -922,8 +922,7 @@ struct hvc_struct *hvc_alloc(uint32_t vtermno, int data,
 			return ERR_PTR(err);
 	}
 
-	hp = kzalloc(ALIGN(sizeof(*hp), sizeof(long)) + outbuf_size,
-			GFP_KERNEL);
+	hp = kzalloc(struct_size(hp, outbuf, outbuf_size), GFP_KERNEL);
 	if (!hp)
 		return ERR_PTR(-ENOMEM);
 
@@ -931,7 +930,6 @@ struct hvc_struct *hvc_alloc(uint32_t vtermno, int data,
 	hp->data = data;
 	hp->ops = ops;
 	hp->outbuf_size = outbuf_size;
-	hp->outbuf = &((char *)hp)[ALIGN(sizeof(*hp), sizeof(long))];
 
 	tty_port_init(&hp->port);
 	hp->port.ops = &hvc_port_ops;
@@ -976,7 +974,7 @@ struct hvc_struct *hvc_alloc(uint32_t vtermno, int data,
 }
 EXPORT_SYMBOL_GPL(hvc_alloc);
 
-int hvc_remove(struct hvc_struct *hp)
+void hvc_remove(struct hvc_struct *hp)
 {
 	unsigned long flags;
 	struct tty_struct *tty;
@@ -1010,7 +1008,6 @@ int hvc_remove(struct hvc_struct *hp)
 		tty_vhangup(tty);
 		tty_kref_put(tty);
 	}
-	return 0;
 }
 EXPORT_SYMBOL_GPL(hvc_remove);
 
diff --git a/drivers/tty/hvc/hvc_console.h b/drivers/tty/hvc/hvc_console.h
index 9668f821d..cf4c1af08 100644
--- a/drivers/tty/hvc/hvc_console.h
+++ b/drivers/tty/hvc/hvc_console.h
@@ -37,7 +37,6 @@ struct hvc_struct {
 	spinlock_t lock;
 	int index;
 	int do_wakeup;
-	char *outbuf;
 	int outbuf_size;
 	int n_outbuf;
 	uint32_t vtermno;
@@ -48,12 +47,13 @@ struct hvc_struct {
 	struct work_struct tty_resize;
 	struct list_head next;
 	unsigned long flags;
+	u8 outbuf[] __aligned(sizeof(long));
 };
 
 /* implemented by a low level driver */
 struct hv_ops {
-	int (*get_chars)(uint32_t vtermno, char *buf, int count);
-	int (*put_chars)(uint32_t vtermno, const char *buf, int count);
+	ssize_t (*get_chars)(uint32_t vtermno, u8 *buf, size_t count);
+	ssize_t (*put_chars)(uint32_t vtermno, const u8 *buf, size_t count);
 	int (*flush)(uint32_t vtermno, bool wait);
 
 	/* Callbacks for notification. Called in open, close and hangup */
@@ -77,7 +77,7 @@ extern int hvc_instantiate(uint32_t vtermno, int index,
 extern struct hvc_struct * hvc_alloc(uint32_t vtermno, int data,
 				     const struct hv_ops *ops, int outbuf_size);
 /* remove a vterm from hvc tty operation (module_exit or hotplug remove) */
-extern int hvc_remove(struct hvc_struct *hp);
+extern void hvc_remove(struct hvc_struct *hp);
 
 /* data available */
 int hvc_poll(struct hvc_struct *hp);
diff --git a/drivers/tty/hvc/hvc_dcc.c b/drivers/tty/hvc/hvc_dcc.c
index 1751108cf..dfc5c9c38 100644
--- a/drivers/tty/hvc/hvc_dcc.c
+++ b/drivers/tty/hvc/hvc_dcc.c
@@ -26,10 +26,10 @@
 /* Lock to serialize access to DCC fifo */
 static DEFINE_SPINLOCK(dcc_lock);
 
-static DEFINE_KFIFO(inbuf, unsigned char, DCC_INBUF_SIZE);
-static DEFINE_KFIFO(outbuf, unsigned char, DCC_OUTBUF_SIZE);
+static DEFINE_KFIFO(inbuf, u8, DCC_INBUF_SIZE);
+static DEFINE_KFIFO(outbuf, u8, DCC_OUTBUF_SIZE);
 
-static void dcc_uart_console_putchar(struct uart_port *port, unsigned char ch)
+static void dcc_uart_console_putchar(struct uart_port *port, u8 ch)
 {
 	while (__dcc_getstatus() & DCC_STATUS_TX)
 		cpu_relax();
@@ -47,6 +47,14 @@ static void dcc_early_write(struct console *con, const char *s, unsigned n)
 static int __init dcc_early_console_setup(struct earlycon_device *device,
 					  const char *opt)
 {
+	unsigned int count = 0x4000000;
+
+	while (--count && (__dcc_getstatus() & DCC_STATUS_TX))
+		cpu_relax();
+
+	if (__dcc_getstatus() & DCC_STATUS_TX)
+		return -ENODEV;
+
 	device->con->write = dcc_early_write;
 
 	return 0;
@@ -54,9 +62,9 @@ static int __init dcc_early_console_setup(struct earlycon_device *device,
 
 EARLYCON_DECLARE(dcc, dcc_early_console_setup);
 
-static int hvc_dcc_put_chars(uint32_t vt, const char *buf, int count)
+static ssize_t hvc_dcc_put_chars(uint32_t vt, const u8 *buf, size_t count)
 {
-	int i;
+	size_t i;
 
 	for (i = 0; i < count; i++) {
 		while (__dcc_getstatus() & DCC_STATUS_TX)
@@ -68,9 +76,9 @@ static int hvc_dcc_put_chars(uint32_t vt, const char *buf, int count)
 	return count;
 }
 
-static int hvc_dcc_get_chars(uint32_t vt, char *buf, int count)
+static ssize_t hvc_dcc_get_chars(uint32_t vt, u8 *buf, size_t count)
 {
-	int i;
+	size_t i;
 
 	for (i = 0; i < count; ++i)
 		if (__dcc_getstatus() & DCC_STATUS_RX)
@@ -149,8 +157,8 @@ static DECLARE_WORK(dcc_pwork, dcc_put_work);
  */
 static void dcc_get_work(struct work_struct *work)
 {
-	unsigned char ch;
 	unsigned long irqflags;
+	u8 ch;
 
 	/*
 	 * Read characters from DCC and put them into the input FIFO, as
@@ -172,10 +180,10 @@ static DECLARE_WORK(dcc_gwork, dcc_get_work);
  * Write characters directly to the DCC if we're on core 0 and the FIFO
  * is empty, or write them to the FIFO if we're not.
  */
-static int hvc_dcc0_put_chars(u32 vt, const char *buf, int count)
+static ssize_t hvc_dcc0_put_chars(u32 vt, const u8 *buf, size_t count)
 {
-	int len;
 	unsigned long irqflags;
+	ssize_t len;
 
 	if (!IS_ENABLED(CONFIG_HVC_DCC_SERIALIZE_SMP))
 		return hvc_dcc_put_chars(vt, buf, count);
@@ -211,10 +219,10 @@ static int hvc_dcc0_put_chars(u32 vt, const char *buf, int count)
  * Read characters directly from the DCC if we're on core 0 and the FIFO
  * is empty, or read them from the FIFO if we're not.
  */
-static int hvc_dcc0_get_chars(u32 vt, char *buf, int count)
+static ssize_t hvc_dcc0_get_chars(u32 vt, u8 *buf, size_t count)
 {
-	int len;
 	unsigned long irqflags;
+	ssize_t len;
 
 	if (!IS_ENABLED(CONFIG_HVC_DCC_SERIALIZE_SMP))
 		return hvc_dcc_get_chars(vt, buf, count);
diff --git a/drivers/tty/hvc/hvc_iucv.c b/drivers/tty/hvc/hvc_iucv.c
index 543f35ddf..fdecc0d63 100644
--- a/drivers/tty/hvc/hvc_iucv.c
+++ b/drivers/tty/hvc/hvc_iucv.c
@@ -215,11 +215,11 @@ static void destroy_tty_buffer_list(struct list_head *list)
  * If the IUCV path has been severed, then -EPIPE is returned to cause a
  * hang up (that is issued by the HVC layer).
  */
-static int hvc_iucv_write(struct hvc_iucv_private *priv,
-			  char *buf, int count, int *has_more_data)
+static ssize_t hvc_iucv_write(struct hvc_iucv_private *priv,
+			      u8 *buf, size_t count, int *has_more_data)
 {
 	struct iucv_tty_buffer *rb;
-	int written;
+	ssize_t written;
 	int rc;
 
 	/* immediately return if there is no IUCV connection */
@@ -312,10 +312,10 @@ out_written:
  *		the routine locks the struct hvc_iucv_private->lock to call
  *		helper functions.
  */
-static int hvc_iucv_get_chars(uint32_t vtermno, char *buf, int count)
+static ssize_t hvc_iucv_get_chars(uint32_t vtermno, u8 *buf, size_t count)
 {
 	struct hvc_iucv_private *priv = hvc_iucv_get_private(vtermno);
-	int written;
+	ssize_t written;
 	int has_more_data;
 
 	if (count <= 0)
@@ -352,8 +352,8 @@ static int hvc_iucv_get_chars(uint32_t vtermno, char *buf, int count)
  * If an existing IUCV communicaton path has been severed, -EPIPE is returned
  * (that can be passed to HVC layer to cause a tty hangup).
  */
-static int hvc_iucv_queue(struct hvc_iucv_private *priv, const char *buf,
-			  int count)
+static ssize_t hvc_iucv_queue(struct hvc_iucv_private *priv, const u8 *buf,
+			      size_t count)
 {
 	size_t len;
 
@@ -455,12 +455,12 @@ static void hvc_iucv_sndbuf_work(struct work_struct *work)
  * Locking:	The method gets called under an irqsave() spinlock; and
  *		locks struct hvc_iucv_private->lock.
  */
-static int hvc_iucv_put_chars(uint32_t vtermno, const char *buf, int count)
+static ssize_t hvc_iucv_put_chars(uint32_t vtermno, const u8 *buf, size_t count)
 {
 	struct hvc_iucv_private *priv = hvc_iucv_get_private(vtermno);
 	int queued;
 
-	if (count <= 0)
+	if (!count)
 		return 0;
 
 	if (!priv)
diff --git a/drivers/tty/hvc/hvc_opal.c b/drivers/tty/hvc/hvc_opal.c
index 992e199e0..095c33ad1 100644
--- a/drivers/tty/hvc/hvc_opal.c
+++ b/drivers/tty/hvc/hvc_opal.c
@@ -58,7 +58,7 @@ static const struct hv_ops hvc_opal_raw_ops = {
 	.notifier_hangup = notifier_hangup_irq,
 };
 
-static int hvc_opal_hvsi_get_chars(uint32_t vtermno, char *buf, int count)
+static ssize_t hvc_opal_hvsi_get_chars(uint32_t vtermno, u8 *buf, size_t count)
 {
 	struct hvc_opal_priv *pv = hvc_opal_privs[vtermno];
 
@@ -68,7 +68,8 @@ static int hvc_opal_hvsi_get_chars(uint32_t vtermno, char *buf, int count)
 	return hvsilib_get_chars(&pv->hvsi, buf, count);
 }
 
-static int hvc_opal_hvsi_put_chars(uint32_t vtermno, const char *buf, int count)
+static ssize_t hvc_opal_hvsi_put_chars(uint32_t vtermno, const u8 *buf,
+				       size_t count)
 {
 	struct hvc_opal_priv *pv = hvc_opal_privs[vtermno];
 
@@ -232,24 +233,21 @@ static int hvc_opal_probe(struct platform_device *dev)
 	return 0;
 }
 
-static int hvc_opal_remove(struct platform_device *dev)
+static void hvc_opal_remove(struct platform_device *dev)
 {
 	struct hvc_struct *hp = dev_get_drvdata(&dev->dev);
-	int rc, termno;
+	int termno;
 
 	termno = hp->vtermno;
-	rc = hvc_remove(hp);
-	if (rc == 0) {
-		if (hvc_opal_privs[termno] != &hvc_opal_boot_priv)
-			kfree(hvc_opal_privs[termno]);
-		hvc_opal_privs[termno] = NULL;
-	}
-	return rc;
+	hvc_remove(hp);
+	if (hvc_opal_privs[termno] != &hvc_opal_boot_priv)
+		kfree(hvc_opal_privs[termno]);
+	hvc_opal_privs[termno] = NULL;
 }
 
 static struct platform_driver hvc_opal_driver = {
 	.probe		= hvc_opal_probe,
-	.remove		= hvc_opal_remove,
+	.remove_new	= hvc_opal_remove,
 	.driver		= {
 		.name	= hvc_opal_name,
 		.of_match_table	= hvc_opal_match,
diff --git a/drivers/tty/hvc/hvc_riscv_sbi.c b/drivers/tty/hvc/hvc_riscv_sbi.c
index 31f53fa77..cede8a572 100644
--- a/drivers/tty/hvc/hvc_riscv_sbi.c
+++ b/drivers/tty/hvc/hvc_riscv_sbi.c
@@ -15,9 +15,9 @@
 
 #include "hvc_console.h"
 
-static int hvc_sbi_tty_put(uint32_t vtermno, const char *buf, int count)
+static ssize_t hvc_sbi_tty_put(uint32_t vtermno, const u8 *buf, size_t count)
 {
-	int i;
+	size_t i;
 
 	for (i = 0; i < count; i++)
 		sbi_console_putchar(buf[i]);
@@ -25,9 +25,10 @@ static int hvc_sbi_tty_put(uint32_t vtermno, const char *buf, int count)
 	return i;
 }
 
-static int hvc_sbi_tty_get(uint32_t vtermno, char *buf, int count)
+static ssize_t hvc_sbi_tty_get(uint32_t vtermno, u8 *buf, size_t count)
 {
-	int i, c;
+	size_t i;
+	int c;
 
 	for (i = 0; i < count; i++) {
 		c = sbi_console_getchar();
@@ -39,21 +40,44 @@ static int hvc_sbi_tty_get(uint32_t vtermno, char *buf, int count)
 	return i;
 }
 
-static const struct hv_ops hvc_sbi_ops = {
+static const struct hv_ops hvc_sbi_v01_ops = {
 	.get_chars = hvc_sbi_tty_get,
 	.put_chars = hvc_sbi_tty_put,
 };
 
-static int __init hvc_sbi_init(void)
+static ssize_t hvc_sbi_dbcn_tty_put(uint32_t vtermno, const u8 *buf, size_t count)
 {
-	return PTR_ERR_OR_ZERO(hvc_alloc(0, 0, &hvc_sbi_ops, 16));
+	return sbi_debug_console_write(buf, count);
 }
-device_initcall(hvc_sbi_init);
 
-static int __init hvc_sbi_console_init(void)
+static ssize_t hvc_sbi_dbcn_tty_get(uint32_t vtermno, u8 *buf, size_t count)
 {
-	hvc_instantiate(0, 0, &hvc_sbi_ops);
+	return sbi_debug_console_read(buf, count);
+}
+
+static const struct hv_ops hvc_sbi_dbcn_ops = {
+	.put_chars = hvc_sbi_dbcn_tty_put,
+	.get_chars = hvc_sbi_dbcn_tty_get,
+};
+
+static int __init hvc_sbi_init(void)
+{
+	int err;
+
+	if (sbi_debug_console_available) {
+		err = PTR_ERR_OR_ZERO(hvc_alloc(0, 0, &hvc_sbi_dbcn_ops, 256));
+		if (err)
+			return err;
+		hvc_instantiate(0, 0, &hvc_sbi_dbcn_ops);
+	} else if (IS_ENABLED(CONFIG_RISCV_SBI_V01)) {
+		err = PTR_ERR_OR_ZERO(hvc_alloc(0, 0, &hvc_sbi_v01_ops, 256));
+		if (err)
+			return err;
+		hvc_instantiate(0, 0, &hvc_sbi_v01_ops);
+	} else {
+		return -ENODEV;
+	}
 
 	return 0;
 }
-console_initcall(hvc_sbi_console_init);
+device_initcall(hvc_sbi_init);
diff --git a/drivers/tty/hvc/hvc_rtas.c b/drivers/tty/hvc/hvc_rtas.c
index 184d325ab..a0b90275b 100644
--- a/drivers/tty/hvc/hvc_rtas.c
+++ b/drivers/tty/hvc/hvc_rtas.c
@@ -31,10 +31,10 @@ static struct hvc_struct *hvc_rtas_dev;
 static int rtascons_put_char_token = RTAS_UNKNOWN_SERVICE;
 static int rtascons_get_char_token = RTAS_UNKNOWN_SERVICE;
 
-static inline int hvc_rtas_write_console(uint32_t vtermno, const char *buf,
-		int count)
+static ssize_t hvc_rtas_write_console(uint32_t vtermno, const u8 *buf,
+				      size_t count)
 {
-	int i;
+	size_t i;
 
 	for (i = 0; i < count; i++) {
 		if (rtas_call(rtascons_put_char_token, 1, 1, NULL, buf[i]))
@@ -44,9 +44,10 @@ static inline int hvc_rtas_write_console(uint32_t vtermno, const char *buf,
 	return i;
 }
 
-static int hvc_rtas_read_console(uint32_t vtermno, char *buf, int count)
+static ssize_t hvc_rtas_read_console(uint32_t vtermno, u8 *buf, size_t count)
 {
-	int i, c;
+	size_t i;
+	int c;
 
 	for (i = 0; i < count; i++) {
 		if (rtas_call(rtascons_get_char_token, 0, 2, &c))
diff --git a/drivers/tty/hvc/hvc_udbg.c b/drivers/tty/hvc/hvc_udbg.c
index ff0dcc564..fdc2699b7 100644
--- a/drivers/tty/hvc/hvc_udbg.c
+++ b/drivers/tty/hvc/hvc_udbg.c
@@ -19,9 +19,9 @@
 
 static struct hvc_struct *hvc_udbg_dev;
 
-static int hvc_udbg_put(uint32_t vtermno, const char *buf, int count)
+static ssize_t hvc_udbg_put(uint32_t vtermno, const u8 *buf, size_t count)
 {
-	int i;
+	size_t i;
 
 	for (i = 0; i < count && udbg_putc; i++)
 		udbg_putc(buf[i]);
@@ -29,9 +29,10 @@ static int hvc_udbg_put(uint32_t vtermno, const char *buf, int count)
 	return i;
 }
 
-static int hvc_udbg_get(uint32_t vtermno, char *buf, int count)
+static ssize_t hvc_udbg_get(uint32_t vtermno, u8 *buf, size_t count)
 {
-	int i, c;
+	size_t i;
+	int c;
 
 	if (!udbg_getc_poll)
 		return 0;
diff --git a/drivers/tty/hvc/hvc_vio.c b/drivers/tty/hvc/hvc_vio.c
index 736b230f5..47930601a 100644
--- a/drivers/tty/hvc/hvc_vio.c
+++ b/drivers/tty/hvc/hvc_vio.c
@@ -58,20 +58,20 @@ struct hvterm_priv {
 	hv_protocol_t		proto;	/* Raw data or HVSI packets */
 	struct hvsi_priv	hvsi;	/* HVSI specific data */
 	spinlock_t		buf_lock;
-	char			buf[SIZE_VIO_GET_CHARS];
-	int			left;
-	int			offset;
+	u8			buf[SIZE_VIO_GET_CHARS];
+	size_t			left;
+	size_t			offset;
 };
 static struct hvterm_priv *hvterm_privs[MAX_NR_HVC_CONSOLES];
 /* For early boot console */
 static struct hvterm_priv hvterm_priv0;
 
-static int hvterm_raw_get_chars(uint32_t vtermno, char *buf, int count)
+static ssize_t hvterm_raw_get_chars(uint32_t vtermno, u8 *buf, size_t count)
 {
 	struct hvterm_priv *pv = hvterm_privs[vtermno];
 	unsigned long i;
 	unsigned long flags;
-	int got;
+	size_t got;
 
 	if (WARN_ON(!pv))
 		return 0;
@@ -115,7 +115,8 @@ static int hvterm_raw_get_chars(uint32_t vtermno, char *buf, int count)
  *       you are sending fewer chars.
  * @count: number of chars to send.
  */
-static int hvterm_raw_put_chars(uint32_t vtermno, const char *buf, int count)
+static ssize_t hvterm_raw_put_chars(uint32_t vtermno, const u8 *buf,
+				    size_t count)
 {
 	struct hvterm_priv *pv = hvterm_privs[vtermno];
 
@@ -133,7 +134,7 @@ static const struct hv_ops hvterm_raw_ops = {
 	.notifier_hangup = notifier_hangup_irq,
 };
 
-static int hvterm_hvsi_get_chars(uint32_t vtermno, char *buf, int count)
+static ssize_t hvterm_hvsi_get_chars(uint32_t vtermno, u8 *buf, size_t count)
 {
 	struct hvterm_priv *pv = hvterm_privs[vtermno];
 
@@ -143,7 +144,8 @@ static int hvterm_hvsi_get_chars(uint32_t vtermno, char *buf, int count)
 	return hvsilib_get_chars(&pv->hvsi, buf, count);
 }
 
-static int hvterm_hvsi_put_chars(uint32_t vtermno, const char *buf, int count)
+static ssize_t hvterm_hvsi_put_chars(uint32_t vtermno, const u8 *buf,
+				     size_t count)
 {
 	struct hvterm_priv *pv = hvterm_privs[vtermno];
 
diff --git a/drivers/tty/hvc/hvc_xen.c b/drivers/tty/hvc/hvc_xen.c
index 34c01874f..0e497501f 100644
--- a/drivers/tty/hvc/hvc_xen.c
+++ b/drivers/tty/hvc/hvc_xen.c
@@ -84,13 +84,13 @@ static inline void notify_daemon(struct xencons_info *cons)
 	notify_remote_via_evtchn(cons->evtchn);
 }
 
-static int __write_console(struct xencons_info *xencons,
-		const char *data, int len)
+static ssize_t __write_console(struct xencons_info *xencons,
+			       const u8 *data, size_t len)
 {
 	XENCONS_RING_IDX cons, prod;
 	struct xencons_interface *intf = xencons->intf;
-	int sent = 0;
 	unsigned long flags;
+	size_t sent = 0;
 
 	spin_lock_irqsave(&xencons->ring_lock, flags);
 	cons = intf->out_cons;
@@ -115,10 +115,11 @@ static int __write_console(struct xencons_info *xencons,
 	return sent;
 }
 
-static int domU_write_console(uint32_t vtermno, const char *data, int len)
+static ssize_t domU_write_console(uint32_t vtermno, const u8 *data, size_t len)
 {
-	int ret = len;
 	struct xencons_info *cons = vtermno_to_xencons(vtermno);
+	size_t ret = len;
+
 	if (cons == NULL)
 		return -EINVAL;
 
@@ -129,7 +130,7 @@ static int domU_write_console(uint32_t vtermno, const char *data, int len)
 	 * kernel is crippled.
 	 */
 	while (len) {
-		int sent = __write_console(cons, data, len);
+		ssize_t sent = __write_console(cons, data, len);
 
 		if (sent < 0)
 			return sent;
@@ -144,14 +145,14 @@ static int domU_write_console(uint32_t vtermno, const char *data, int len)
 	return ret;
 }
 
-static int domU_read_console(uint32_t vtermno, char *buf, int len)
+static ssize_t domU_read_console(uint32_t vtermno, u8 *buf, size_t len)
 {
 	struct xencons_interface *intf;
 	XENCONS_RING_IDX cons, prod;
-	int recv = 0;
 	struct xencons_info *xencons = vtermno_to_xencons(vtermno);
 	unsigned int eoiflag = 0;
 	unsigned long flags;
+	size_t recv = 0;
 
 	if (xencons == NULL)
 		return -EINVAL;
@@ -209,7 +210,7 @@ static const struct hv_ops domU_hvc_ops = {
 	.notifier_hangup = notifier_hangup_irq,
 };
 
-static int dom0_read_console(uint32_t vtermno, char *buf, int len)
+static ssize_t dom0_read_console(uint32_t vtermno, u8 *buf, size_t len)
 {
 	return HYPERVISOR_console_io(CONSOLEIO_read, len, buf);
 }
@@ -218,9 +219,9 @@ static int dom0_read_console(uint32_t vtermno, char *buf, int len)
  * Either for a dom0 to write to the system console, or a domU with a
  * debug version of Xen
  */
-static int dom0_write_console(uint32_t vtermno, const char *str, int len)
+static ssize_t dom0_write_console(uint32_t vtermno, const u8 *str, size_t len)
 {
-	int rc = HYPERVISOR_console_io(CONSOLEIO_write, len, (char *)str);
+	int rc = HYPERVISOR_console_io(CONSOLEIO_write, len, (u8 *)str);
 	if (rc < 0)
 		return rc;
 
diff --git a/drivers/tty/hvc/hvsi_lib.c b/drivers/tty/hvc/hvsi_lib.c
index 09289c815..22e1bc4d8 100644
--- a/drivers/tty/hvc/hvsi_lib.c
+++ b/drivers/tty/hvc/hvsi_lib.c
@@ -12,7 +12,7 @@ static int hvsi_send_packet(struct hvsi_priv *pv, struct hvsi_header *packet)
 	packet->seqno = cpu_to_be16(atomic_inc_return(&pv->seqno));
 
 	/* Assumes that always succeeds, works in practice */
-	return pv->put_chars(pv->termno, (char *)packet, packet->len);
+	return pv->put_chars(pv->termno, (u8 *)packet, packet->len);
 }
 
 static void hvsi_start_handshake(struct hvsi_priv *pv)
@@ -178,9 +178,10 @@ static int hvsi_get_packet(struct hvsi_priv *pv)
 	return 0;
 }
 
-int hvsilib_get_chars(struct hvsi_priv *pv, char *buf, int count)
+ssize_t hvsilib_get_chars(struct hvsi_priv *pv, u8 *buf, size_t count)
 {
-	unsigned int tries, read = 0;
+	unsigned int tries;
+	size_t read = 0;
 
 	if (WARN_ON(!pv))
 		return -ENXIO;
@@ -199,7 +200,7 @@ int hvsilib_get_chars(struct hvsi_priv *pv, char *buf, int count)
 	for (tries = 1; count && tries < 2; tries++) {
 		/* Consume existing data packet */
 		if (pv->inbuf_pktlen) {
-			unsigned int l = min(count, (int)pv->inbuf_pktlen);
+			size_t l = min(count, pv->inbuf_pktlen);
 			memcpy(&buf[read], &pv->inbuf[pv->inbuf_cur], l);
 			pv->inbuf_cur += l;
 			pv->inbuf_pktlen -= l;
@@ -228,10 +229,11 @@ int hvsilib_get_chars(struct hvsi_priv *pv, char *buf, int count)
 	return read;
 }
 
-int hvsilib_put_chars(struct hvsi_priv *pv, const char *buf, int count)
+ssize_t hvsilib_put_chars(struct hvsi_priv *pv, const u8 *buf, size_t count)
 {
 	struct hvsi_data dp;
-	int rc, adjcount = min(count, HVSI_MAX_OUTGOING_DATA);
+	size_t adjcount = min_t(size_t, count, HVSI_MAX_OUTGOING_DATA);
+	int rc;
 
 	if (WARN_ON(!pv))
 		return -ENODEV;
@@ -411,9 +413,9 @@ void hvsilib_close(struct hvsi_priv *pv, struct hvc_struct *hp)
 }
 
 void hvsilib_init(struct hvsi_priv *pv,
-		  int (*get_chars)(uint32_t termno, char *buf, int count),
-		  int (*put_chars)(uint32_t termno, const char *buf,
-				   int count),
+		  ssize_t (*get_chars)(uint32_t termno, u8 *buf, size_t count),
+		  ssize_t (*put_chars)(uint32_t termno, const u8 *buf,
+				       size_t count),
 		  int termno, int is_console)
 {
 	memset(pv, 0, sizeof(*pv));