s390: use virtio_console for KVM on s390
This patch enables virtio_console as the default console on kvm for
s390. We currently use the same notify hack as lguest for early
console output. I will try to address this for lguest and s390 later.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
diff --git a/drivers/s390/kvm/kvm_virtio.c b/drivers/s390/kvm/kvm_virtio.c
index 5ab3434..d41f234 100644
--- a/drivers/s390/kvm/kvm_virtio.c
+++ b/drivers/s390/kvm/kvm_virtio.c
@@ -15,6 +15,7 @@
#include <linux/err.h>
#include <linux/virtio.h>
#include <linux/virtio_config.h>
+#include <linux/virtio_console.h>
#include <linux/interrupt.h>
#include <linux/virtio_ring.h>
#include <linux/pfn.h>
@@ -333,6 +334,25 @@
return 0;
}
+/* code for early console output with virtio_console */
+static __init int early_put_chars(u32 vtermno, const char *buf, int count)
+{
+ char scratch[17];
+ unsigned int len = count;
+
+ if (len > sizeof(scratch) - 1)
+ len = sizeof(scratch) - 1;
+ scratch[len] = '\0';
+ memcpy(scratch, buf, len);
+ kvm_hypercall1(KVM_S390_VIRTIO_NOTIFY, __pa(scratch));
+ return len;
+}
+
+void s390_virtio_console_init(void)
+{
+ virtio_cons_early_init(early_put_chars);
+}
+
/*
* We do this after core stuff, but before the drivers.
*/