From 62b0e0c94beefd2134a5eb09c10b69b964e78aa9 Mon Sep 17 00:00:00 2001
From: Juan Quintela <quintela@redhat.com>
Date: Mon, 26 Nov 2007 07:38:29 +0100
Subject: [PATCH] xen dom0: Make hvc_xen console work for dom0.

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
---
 arch/x86/xen/events.c  |    2 +-
 drivers/char/hvc_xen.c |   61 +++++++++++++++++++++++++++++++++++++++++------
 include/xen/events.h   |    2 +
 3 files changed, 56 insertions(+), 9 deletions(-)

diff --git a/arch/x86/xen/events.c b/arch/x86/xen/events.c
index 6d1da58..2bf9731 100644
--- a/arch/x86/xen/events.c
+++ b/arch/x86/xen/events.c
@@ -311,7 +311,7 @@ static int bind_ipi_to_irq(unsigned int ipi, unsigned int cpu)
 }
 
 
-static int bind_virq_to_irq(unsigned int virq, unsigned int cpu)
+int bind_virq_to_irq(unsigned int virq, unsigned int cpu)
 {
 	struct evtchn_bind_virq bind_virq;
 	int evtchn, irq;
diff --git a/drivers/char/hvc_xen.c b/drivers/char/hvc_xen.c
index dd68f85..511fa6a 100644
--- a/drivers/char/hvc_xen.c
+++ b/drivers/char/hvc_xen.c
@@ -50,7 +50,7 @@ static inline void notify_daemon(void)
 	notify_remote_via_evtchn(xen_start_info->console.domU.evtchn);
 }
 
-static int write_console(uint32_t vtermno, const char *data, int len)
+static int domU_write_console(uint32_t vtermno, const char *data, int len)
 {
 	struct xencons_interface *intf = xencons_interface();
 	XENCONS_RING_IDX cons, prod;
@@ -71,7 +71,28 @@ static int write_console(uint32_t vtermno, const char *data, int len)
 	return sent;
 }
 
-static int read_console(uint32_t vtermno, char *buf, int len)
+static int dom0_write_console(uint32_t vtermno, const char *data, int len)
+{
+	int ret;
+
+	ret = HYPERVISOR_console_io(CONSOLEIO_write, len, (char *)data);
+
+	return ret < 0 ? 0 : len;
+}
+
+static int write_console(uint32_t vtermno, const char *data, int len)
+{
+	int ret;
+
+	if (is_initial_xendomain())
+		ret = dom0_write_console(vtermno, data, len);
+	else
+		ret = domU_write_console(vtermno, data, len);
+
+	return ret;
+}
+
+static int domU_read_console(uint32_t vtermno, char *buf, int len)
 {
 	struct xencons_interface *intf = xencons_interface();
 	XENCONS_RING_IDX cons, prod;
@@ -92,22 +113,40 @@ static int read_console(uint32_t vtermno, char *buf, int len)
 	return recv;
 }
 
-static struct hv_ops hvc_ops = {
-	.get_chars = read_console,
-	.put_chars = write_console,
+static int dom0_read_console(uint32_t vtermno, char *buf, int len)
+{
+	return HYPERVISOR_console_io(CONSOLEIO_read, len, buf);
+}
+
+static struct hv_ops domU_hvc_ops = {
+	.get_chars = domU_read_console,
+	.put_chars = domU_write_console,
+};
+
+static struct hv_ops dom0_hvc_ops = {
+	.get_chars = dom0_read_console,
+	.put_chars = dom0_write_console,
 };
 
 static int __init xen_init(void)
 {
 	struct hvc_struct *hp;
+	struct hv_ops *ops;
 
 	if (!is_running_on_xen())
 		return 0;
 
-	xencons_irq = bind_evtchn_to_irq(xen_start_info->console.domU.evtchn);
+	if (is_initial_xendomain()) {
+		ops = &dom0_hvc_ops;
+		xencons_irq = bind_virq_to_irq(VIRQ_CONSOLE, smp_processor_id());
+	} else {
+		ops = &domU_hvc_ops;
+		xencons_irq = bind_evtchn_to_irq(xen_start_info->console.domU.evtchn);
+	}
+
 	if (xencons_irq < 0)
 		xencons_irq = 0 /* NO_IRQ */;
-	hp = hvc_alloc(HVC_COOKIE, xencons_irq, &hvc_ops, 256);
+	hp = hvc_alloc(HVC_COOKIE, xencons_irq, ops, 256);
 	if (IS_ERR(hp))
 		return PTR_ERR(hp);
 
@@ -123,10 +162,16 @@ static void __exit xen_fini(void)
 
 static int xen_cons_init(void)
 {
+	struct hv_ops *ops;
+
 	if (!is_running_on_xen())
 		return 0;
 
-	hvc_instantiate(HVC_COOKIE, 0, &hvc_ops);
+	ops = &domU_hvc_ops;
+	if (is_initial_xendomain())
+		ops = &dom0_hvc_ops;
+
+	hvc_instantiate(HVC_COOKIE, 0, ops);
 	return 0;
 }
 
diff --git a/include/xen/events.h b/include/xen/events.h
index 2bde54d..0436486 100644
--- a/include/xen/events.h
+++ b/include/xen/events.h
@@ -18,6 +18,8 @@ int bind_evtchn_to_irqhandler(unsigned int evtchn,
 			      irq_handler_t handler,
 			      unsigned long irqflags, const char *devname,
 			      void *dev_id);
+int bind_virq_to_irq(unsigned int virq, unsigned int cpu);
+
 int bind_virq_to_irqhandler(unsigned int virq, unsigned int cpu,
 			    irq_handler_t handler,
 			    unsigned long irqflags, const char *devname,
-- 
1.5.3.4