Re: [Qemu-devel] [PATCH 4/4] acpi-build: simplify rsdp management for legacy

[Igor Mammedov]

On Tue, 17 Feb 2015 11:05:45 +0100
"Michael S. Tsirkin" <address@hidden> wrote:

> For legacy machine types, rsdp is not in RAM, so we need a copy of rsdp
> for fw cfg. We previously used g_array_free with false parameter,
> but this seems to confuse people.
> This also wastes a bit of memory as the buffer is unused for new
> machine types.
> 
> Let's just use plain g_memdup, and free original memory together with
> the array.
> 
> TODO: rationalize tcpalog memory management, and get rid of the mfre
> parameter.
> 
> Signed-off-by: Michael S. Tsirkin <address@hidden>
Reviewed-by: Igor Mammedov <address@hidden>

> ---
>  hw/i386/acpi-build.c | 10 ++++++----
>  1 file changed, 6 insertions(+), 4 deletions(-)
> 
> diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
> index ffa3f00..f712277 100644
> --- a/hw/i386/acpi-build.c
> +++ b/hw/i386/acpi-build.c
> @@ -1257,7 +1257,7 @@ static inline void 
> acpi_build_tables_cleanup(AcpiBuildTables *tables, bool mfre)
>  {
>      void *linker_data = bios_linker_loader_cleanup(tables->linker);
>      g_free(linker_data);
> -    g_array_free(tables->rsdp, mfre);
> +    g_array_free(tables->rsdp, true);
>      g_array_free(tables->table_data, true);
>      g_array_free(tables->tcpalog, mfre);
>  }
> @@ -1560,12 +1560,14 @@ void acpi_setup(PcGuestInfo *guest_info)
>          /*
>           * Keep for compatibility with old machine types.
>           * Though RSDP is small, its contents isn't immutable, so
> -         * update it along with the rest of tables on guest access.
> +         * we'll update it along with the rest of tables on guest access.
>           */
> +        uint32_t rsdp_size = acpi_data_len(tables.rsdp);
> +
> +        build_state->rsdp = g_memdup(tables.rsdp->data, rsdp_size);
>          fw_cfg_add_file_callback(guest_info->fw_cfg, ACPI_BUILD_RSDP_FILE,
>                                   acpi_build_update, build_state,
> -                                 tables.rsdp->data, 
> acpi_data_len(tables.rsdp));
> -        build_state->rsdp = tables.rsdp->data;
> +                                 build_state->rsdp, rsdp_size);
>          build_state->rsdp_ram = (ram_addr_t)-1;
>      } else {
>          build_state->rsdp = NULL;