Re: [Qemu-devel] [Qemu-arm] [PATCH v3 12/19] qom/cpu: Add MemoryRegion property

[Peter Crosthwaite]

CC Andrew,

This may be the missing feature for your system_memory for CPU RAM
access problem.

Regards,
Peter

On Thu, Jan 14, 2016 at 5:52 AM, Peter Maydell <address@hidden> wrote:
> From: Peter Crosthwaite <address@hidden>
>
> Add a MemoryRegion property, which if set is used to construct
> the CPU's initial (default) AddressSpace.
>
> Signed-off-by: Peter Crosthwaite <address@hidden>
> [PMM: code is moved from qom/cpu.c to exec.c to avoid having to
>  make qom/cpu.o be a non-common object file; code to use the
>  MemoryRegion and to default it to system_memory added.]
> Signed-off-by: Peter Maydell <address@hidden>
> Acked-by: Edgar E. Iglesias <address@hidden>
> ---
>  cpus.c            |  4 +++-
>  exec.c            | 14 ++++++++++++++
>  include/qom/cpu.h |  1 +
>  3 files changed, 18 insertions(+), 1 deletion(-)
>
> diff --git a/cpus.c b/cpus.c
> index 725a51d..3efff6b 100644
> --- a/cpus.c
> +++ b/cpus.c
> @@ -1375,8 +1375,10 @@ void qemu_init_vcpu(CPUState *cpu)
>          /* If the target cpu hasn't set up any address spaces itself,
>           * give it the default one.
>           */
> +        AddressSpace *as = address_space_init_shareable(cpu->memory,
> +                                                        "cpu-memory");
>          cpu->num_ases = 1;
> -        cpu_address_space_init(cpu, &address_space_memory, 0);
> +        cpu_address_space_init(cpu, as, 0);
>      }
>
>      if (kvm_enabled()) {
> diff --git a/exec.c b/exec.c
> index 0e4f681..5a1b208 100644
> --- a/exec.c
> +++ b/exec.c
> @@ -628,6 +628,20 @@ void cpu_exec_init(CPUState *cpu, Error **errp)
>
>  #ifndef CONFIG_USER_ONLY
>      cpu->thread_id = qemu_get_thread_id();
> +
> +    /* This is a softmmu CPU object, so create a property for it
> +     * so users can wire up its memory. (This can't go in qom/cpu.c
> +     * because that file is compiled only once for both user-mode
> +     * and system builds.) The default if no link is set up is to use
> +     * the system address space.
> +     */
> +    object_property_add_link(OBJECT(cpu), "memory", TYPE_MEMORY_REGION,
> +                             (Object **)&cpu->memory,
> +                             qdev_prop_allow_set_link_before_realize,
> +                             OBJ_PROP_LINK_UNREF_ON_RELEASE,
> +                             &error_abort);
> +    cpu->memory = system_memory;
> +    object_ref(OBJECT(cpu->memory));
>  #endif
>
>  #if defined(CONFIG_USER_ONLY)
> diff --git a/include/qom/cpu.h b/include/qom/cpu.h
> index ed23246..2e5229d 100644
> --- a/include/qom/cpu.h
> +++ b/include/qom/cpu.h
> @@ -297,6 +297,7 @@ struct CPUState {
>      CPUAddressSpace *cpu_ases;
>      int num_ases;
>      AddressSpace *as;
> +    MemoryRegion *memory;
>
>      void *env_ptr; /* CPUArchState */
>      struct TranslationBlock *current_tb;
> --
> 1.9.1
>
>