Re: [Qemu-devel] [PATCH v8 10/20] cpu: introduce CPUClass::virtio_is_big_endian()

[Alexander Graf <agraf@suse.de>]

On 13.06.14 13:22, Greg Kurz wrote:
> If we want to support targets that can change endianness (modern PPC and
> ARM for the moment), we need to add a per-CPU class method to be called
> from the virtio code. The virtio_ prefix in the name is a hint for people
> to avoid misusage (aka. anywhere but from the virtio code).
>
> The default behaviour is to return the compile-time default target
> endianness.
>
> Suggested-by: Peter Maydell <peter.maydell@linaro.org>
> Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
> ---
>   include/qom/cpu.h |   10 ++++++++++
>   qom/cpu.c         |    6 ++++++
>   2 files changed, 16 insertions(+)
>
> diff --git a/include/qom/cpu.h b/include/qom/cpu.h
> index 4b352a2..30e8fe3 100644
> --- a/include/qom/cpu.h
> +++ b/include/qom/cpu.h
> @@ -116,6 +116,7 @@ typedef struct CPUClass {
>       CPUUnassignedAccess do_unassigned_access;
>       void (*do_unaligned_access)(CPUState *cpu, vaddr addr,
>                                   int is_write, int is_user, uintptr_t retaddr);
> +    bool (*virtio_is_big_endian)(CPUState *cpu);
>       int (*memory_rw_debug)(CPUState *cpu, vaddr addr,
>                              uint8_t *buf, int len, bool is_write);
>       void (*dump_state)(CPUState *cpu, FILE *f, fprintf_function cpu_fprintf,
> @@ -548,6 +549,15 @@ void cpu_interrupt(CPUState *cpu, int mask);
>   
>   #endif /* USER_ONLY */
>   
> +#ifndef CONFIG_USER_ONLY
> +static inline bool cpu_virtio_is_big_endian(CPUState *cpu)
> +{
> +    CPUClass *cc = CPU_GET_CLASS(cpu);
> +
> +    return cc->virtio_is_big_endian(cpu);
> +}
> +#endif
> +

Why? Just do this from virtio code directly.


Alex