From: Christian Borntraeger Date: Fri, 20 Jun 2008 13:24:18 +0000 (+0200) Subject: s390: use virtio_console for KVM on s390 X-Git-Tag: v2.6.27-rc1~504^2~3 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=faeba830b086bc9e58748869054e994cb09693cd;p=linux-2.6 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 Signed-off-by: Rusty Russell --- diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig index eb530b4128..2ed88122be 100644 --- a/arch/s390/Kconfig +++ b/arch/s390/Kconfig @@ -565,6 +565,7 @@ bool "s390 guest support (EXPERIMENTAL)" depends on 64BIT && EXPERIMENTAL select VIRTIO select VIRTIO_RING + select VIRTIO_CONSOLE help Select this option if you want to run the kernel under s390 linux endmenu diff --git a/arch/s390/kernel/setup.c b/arch/s390/kernel/setup.c index b358e18273..62122bad1e 100644 --- a/arch/s390/kernel/setup.c +++ b/arch/s390/kernel/setup.c @@ -54,6 +54,7 @@ #include #include #include +#include long psw_kernel_bits = (PSW_BASE_BITS | PSW_MASK_DAT | PSW_ASC_PRIMARY | PSW_MASK_MCHECK | PSW_DEFAULT_KEY); @@ -766,7 +767,8 @@ setup_arch(char **cmdline_p) printk("We are running under VM (64 bit mode)\n"); else if (MACHINE_IS_KVM) { printk("We are running under KVM (64 bit mode)\n"); - add_preferred_console("ttyS", 1, NULL); + add_preferred_console("hvc", 0, NULL); + s390_virtio_console_init(); } else printk("We are running native (64 bit mode)\n"); #endif /* CONFIG_64BIT */ diff --git a/drivers/s390/kvm/kvm_virtio.c b/drivers/s390/kvm/kvm_virtio.c index 5ab3434091..d41f234bb2 100644 --- a/drivers/s390/kvm/kvm_virtio.c +++ b/drivers/s390/kvm/kvm_virtio.c @@ -15,6 +15,7 @@ #include #include #include +#include #include #include #include @@ -333,6 +334,25 @@ static int __init kvm_devices_init(void) 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. */ diff --git a/include/asm-s390/kvm_virtio.h b/include/asm-s390/kvm_virtio.h index 5c871a990c..146100224d 100644 --- a/include/asm-s390/kvm_virtio.h +++ b/include/asm-s390/kvm_virtio.h @@ -50,4 +50,14 @@ struct kvm_vqconfig { #define KVM_S390_VIRTIO_RESET 1 #define KVM_S390_VIRTIO_SET_STATUS 2 +#ifdef __KERNEL__ +/* early virtio console setup */ +#ifdef CONFIG_VIRTIO_CONSOLE +extern void s390_virtio_console_init(void); +#else +static inline void s390_virtio_console_init(void) +{ +} +#endif /* CONFIG_VIRTIO_CONSOLE */ +#endif /* __KERNEL__ */ #endif