Re: [PATCH 5/5] KVM: s390: Split out early console code.

Alexander Graf
2012-12-09T12:45:47Z

On 07.12.2012, at 13:29, Cornelia Huck wrote:

> This code is transport agnostic and can be used by both the legacy
> virtio code and virtio_ccw.

This code should die. It's a nightmare to implement in QEMU, because it ends up being a separate char device. I'd prefer if we don't carry it over to the virtio-ccw world :).

Alex

>
> Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
> Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
> ---
> drivers/s390/kvm/Makefile | 2 +-
> drivers/s390/kvm/early_printk.c | 42 +++++++++++++++++++++++++++++++++++++++++
> drivers/s390/kvm/kvm_virtio.c | 29 ++--------------------------
> drivers/s390/kvm/virtio_ccw.c | 1 -
> 4 files changed, 45 insertions(+), 29 deletions(-)
> create mode 100644 drivers/s390/kvm/early_printk.c
>
> diff --git a/drivers/s390/kvm/Makefile b/drivers/s390/kvm/Makefile
> index 241891a..a3c8fc4 100644
> --- a/drivers/s390/kvm/Makefile
> +++ b/drivers/s390/kvm/Makefile
> @@ -6,4 +6,4 @@
> # it under the terms of the GNU General Public License (version 2 only)
> # as published by the Free Software Foundation.
>
> -obj-$(CONFIG_S390_GUEST) += kvm_virtio.o virtio_ccw.o
> +obj-$(CONFIG_S390_GUEST) += kvm_virtio.o early_printk.o virtio_ccw.o
> diff --git a/drivers/s390/kvm/early_printk.c b/drivers/s390/kvm/early_printk.c
> new file mode 100644
> index 0000000..915d687
> --- /dev/null
> +++ b/drivers/s390/kvm/early_printk.c
> @@ -0,0 +1,42 @@
> +/*
> + * early_printk.c - code for early console output with virtio_console
> + * split off from kvm_virtio.c
> + *
> + * Copyright IBM Corp. 2008
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License (version 2 only)
> + * as published by the Free Software Foundation.
> + *
> + * Author(s): Christian Borntraeger <borntraeger@de.ibm.com>
> + */
> +
> +#include <linux/kernel_stat.h>
> +#include <linux/init.h>
> +#include <linux/err.h>
> +#include <linux/virtio_console.h>
> +#include <linux/kvm_para.h>
> +#include <asm/kvm_virtio.h>
> +#include <asm/setup.h>
> +#include <asm/sclp.h>
> +
> +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;
> +}
> +
> +static int __init s390_virtio_console_init(void)
> +{
> + if (sclp_has_vt220() || sclp_has_linemode())
> + return -ENODEV;
> + return virtio_cons_early_init(early_put_chars);
> +}
> +console_initcall(s390_virtio_console_init);
> diff --git a/drivers/s390/kvm/kvm_virtio.c b/drivers/s390/kvm/kvm_virtio.c
> index 779e480..6ca06ed 100644
> --- a/drivers/s390/kvm/kvm_virtio.c
> +++ b/drivers/s390/kvm/kvm_virtio.c
> @@ -17,7 +17,6 @@
> #include <linux/virtio.h>
> #include <linux/virtio_config.h>
> #include <linux/slab.h>
> -#include <linux/virtio_console.h>
> #include <linux/interrupt.h>
> #include <linux/virtio_ring.h>
> #include <linux/export.h>
> @@ -25,9 +24,9 @@
> #include <asm/io.h>
> #include <asm/kvm_para.h>
> #include <asm/kvm_virtio.h>
> -#include <asm/sclp.h>
> #include <asm/setup.h>
> #include <asm/irq.h>
> +#include <asm/sclp.h>
>
> #define VIRTIO_SUBCODE_64 0x0D00
>
> @@ -453,8 +452,7 @@ static int __init kvm_devices_init(void)
> return -ENODEV;
>
> if (test_devices_support(real_memory_size) < 0)
> - /* No error. */
> - return 0;
> + return -ENODEV;
>
> rc = vmem_add_mapping(real_memory_size, PAGE_SIZE);
> if (rc)
> @@ -479,29 +477,6 @@ 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;
> -}
> -
> -static int __init s390_virtio_console_init(void)
> -{
> - if (sclp_has_vt220() || sclp_has_linemode())
> - return -ENODEV;
> - return virtio_cons_early_init(early_put_chars);
> -}
> -console_initcall(s390_virtio_console_init);
> -
> -
> /*
> * We do this after core stuff, but before the drivers.
> */
> diff --git a/drivers/s390/kvm/virtio_ccw.c b/drivers/s390/kvm/virtio_ccw.c
> index 0e98b523a..1350391 100644
> --- a/drivers/s390/kvm/virtio_ccw.c
> +++ b/drivers/s390/kvm/virtio_ccw.c
> @@ -17,7 +17,6 @@
> #include <linux/virtio.h>
> #include <linux/virtio_config.h>
> #include <linux/slab.h>
> -#include <linux/virtio_console.h>
> #include <linux/interrupt.h>
> #include <linux/virtio_ring.h>
> #include <linux/pfn.h>
> --
> 1.7.12.4
>