Re: [PATCH v3 08/35] acpi: build_mcfg: use acpi_table_begin()/acpi_table_end() instead of build_header()

[Eric Auger]

On 9/7/21 4:47 PM, Igor Mammedov wrote:
> it replaces error-prone pointer arithmetic for build_header() API,
> with 2 calls to start and finish table creation,
> which hides offsets magic from API user.
> 
> Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>

Eric
> ---
> v3:
>   * s/acpi_init_table|acpi_table_composed/acpi_table_begin|acpi_table_end/
> ---
>  hw/acpi/pci.c | 18 +++++++++---------
>  1 file changed, 9 insertions(+), 9 deletions(-)
> 
> diff --git a/hw/acpi/pci.c b/hw/acpi/pci.c
> index 75b1103ec4..20b70dcd81 100644
> --- a/hw/acpi/pci.c
> +++ b/hw/acpi/pci.c
> @@ -28,19 +28,20 @@
>  #include "hw/acpi/pci.h"
>  #include "hw/pci/pcie_host.h"
>  
> +/*
> + * PCI Firmware Specification, Revision 3.0
> + * 4.1.2 MCFG Table Description.
> + */
>  void build_mcfg(GArray *table_data, BIOSLinker *linker, AcpiMcfgInfo *info,
>                  const char *oem_id, const char *oem_table_id)
>  {
> -    int mcfg_start = table_data->len;
> +    AcpiTable table = { .sig = "MCFG", .rev = 1,
> +                        .oem_id = oem_id, .oem_table_id = oem_table_id };
> +
> +    acpi_table_begin(&table, table_data);
>  
> -    /*
> -     * PCI Firmware Specification, Revision 3.0
> -     * 4.1.2 MCFG Table Description.
> -     */
> -    acpi_data_push(table_data, sizeof(AcpiTableHeader));
>      /* Reserved */
>      build_append_int_noprefix(table_data, 0, 8);
> -
>      /*
>       * Memory Mapped Enhanced Configuration Space Base Address Allocation
>       * Structure
> @@ -56,6 +57,5 @@ void build_mcfg(GArray *table_data, BIOSLinker *linker, 
> AcpiMcfgInfo *info,
>      /* Reserved */
>      build_append_int_noprefix(table_data, 0, 4);
>  
> -    build_header(linker, table_data, (void *)(table_data->data + mcfg_start),
> -                 "MCFG", table_data->len - mcfg_start, 1, oem_id, 
> oem_table_id);
> +    acpi_table_end(linker, &table);
>  }
>