Re: [Qemu-devel] [PATCH v4 3/7] hw/acpi: extract standard table headers as a standalone structure

[Anthony Liguori <anthony@codemonkey.ws>]

Laszlo Ersek <lersek@redhat.com> writes:

> This enables reuse when preparing per-table fw_cfg blobs later.
>
> Signed-off-by: Laszlo Ersek <lersek@redhat.com>
> Acked-by: Michael S. Tsirkin <mst@redhat.com>
> ---
>  include/hw/acpi/acpi.h |   11 +++++++++++
>  hw/acpi/core.c         |   48 +++++++++++++++++++++---------------------------
>  2 files changed, 32 insertions(+), 27 deletions(-)
>
> diff --git a/include/hw/acpi/acpi.h b/include/hw/acpi/acpi.h
> index 635be7b..0e26f63 100644
> --- a/include/hw/acpi/acpi.h
> +++ b/include/hw/acpi/acpi.h
> @@ -167,4 +167,15 @@ extern size_t acpi_tables_len;
>  
>  void acpi_table_add(const QemuOpts *opts, Error **errp);
>  
> +typedef struct acpi_table_std_header {
> +    char sig[4];              /* ACPI signature (4 ASCII characters) */
> +    uint32_t length;          /* Length of table, in bytes, including header */
> +    uint8_t revision;         /* ACPI Specification minor version # */
> +    uint8_t checksum;         /* To make sum of entire table == 0 */
> +    char oem_id[6];           /* OEM identification */
> +    char oem_table_id[8];     /* OEM table identification */
> +    uint32_t oem_revision;    /* OEM revision number */
> +    char asl_compiler_id[4];  /* ASL compiler vendor ID */
> +    uint32_t asl_compiler_revision; /* ASL compiler revision number */
> +} QEMU_PACKED AcpiTableStdHdr;

Since you're giving it a CamelCaseName why don't you do the same for the
struct.  After that:

Reviewed-by: Anthony Liguori <aliguori@us.ibm.com>

Regards,

Anthony Liguori

>  #endif /* !QEMU_HW_ACPI_H */
> diff --git a/hw/acpi/core.c b/hw/acpi/core.c
> index 69cadb0..d348f81 100644
> --- a/hw/acpi/core.c
> +++ b/hw/acpi/core.c
> @@ -31,21 +31,13 @@
>  struct acpi_table_header {
>      uint16_t _length;         /* our length, not actual part of the hdr */
>                                /* allows easier parsing for fw_cfg clients */
> -    char sig[4];              /* ACPI signature (4 ASCII characters) */
> -    uint32_t length;          /* Length of table, in bytes, including header */
> -    uint8_t revision;         /* ACPI Specification minor version # */
> -    uint8_t checksum;         /* To make sum of entire table == 0 */
> -    char oem_id[6];           /* OEM identification */
> -    char oem_table_id[8];     /* OEM table identification */
> -    uint32_t oem_revision;    /* OEM revision number */
> -    char asl_compiler_id[4];  /* ASL compiler vendor ID */
> -    uint32_t asl_compiler_revision; /* ASL compiler revision number */
> +    AcpiTableStdHdr std;
>  } QEMU_PACKED;
>  
> -#define ACPI_TABLE_HDR_SIZE sizeof(struct acpi_table_header)
> -#define ACPI_TABLE_PFX_SIZE sizeof(uint16_t)  /* size of the extra prefix */
> +/* size of the extra prefix */
> +#define ACPI_TABLE_PFX_SIZE offsetof(struct acpi_table_header, std)
>  
> -static const char unsigned dfl_hdr[ACPI_TABLE_HDR_SIZE - ACPI_TABLE_PFX_SIZE] =
> +static const char unsigned dfl_hdr[sizeof(AcpiTableStdHdr)] =
>      "QEMU\0\0\0\0\1\0"       /* sig (4), len(4), revno (1), csum (1) */
>      "QEMUQEQEMUQEMU\1\0\0\0" /* OEM id (6), table (8), revno (4) */
>      "QEMU\1\0\0\0"           /* ASL compiler ID (4), version (4) */
> @@ -105,6 +97,7 @@ static void acpi_table_install(const char unsigned *blob, size_t bloblen,
>      size_t body_size, acpi_payload_size;
>      struct acpi_table_header *ext_hdr;
>      unsigned changed_fields;
> +    AcpiTableStdHdr *std;
>  
>      /* Calculate where the ACPI table body starts within the blob, plus where
>       * to copy the ACPI table header from.
> @@ -177,46 +170,47 @@ static void acpi_table_install(const char unsigned *blob, size_t bloblen,
>      changed_fields = 0;
>      ext_hdr->_length = cpu_to_le16(acpi_payload_size);
>  
> +    std = &ext_hdr->std;
>      if (hdrs->has_sig) {
> -        strncpy(ext_hdr->sig, hdrs->sig, sizeof ext_hdr->sig);
> +        strncpy(std->sig, hdrs->sig, sizeof std->sig);
>          ++changed_fields;
>      }
>  
> -    if (has_header && le32_to_cpu(ext_hdr->length) != acpi_payload_size) {
> +    if (has_header && le32_to_cpu(std->length) != acpi_payload_size) {
>          fprintf(stderr,
>                  "warning: ACPI table has wrong length, header says "
>                  "%" PRIu32 ", actual size %zu bytes\n",
> -                le32_to_cpu(ext_hdr->length), acpi_payload_size);
> +                le32_to_cpu(std->length), acpi_payload_size);
>      }
> -    ext_hdr->length = cpu_to_le32(acpi_payload_size);
> +    std->length = cpu_to_le32(acpi_payload_size);
>  
>      if (hdrs->has_rev) {
> -        ext_hdr->revision = hdrs->rev;
> +        std->revision = hdrs->rev;
>          ++changed_fields;
>      }
>  
> -    ext_hdr->checksum = 0;
> +    std->checksum = 0;
>  
>      if (hdrs->has_oem_id) {
> -        strncpy(ext_hdr->oem_id, hdrs->oem_id, sizeof ext_hdr->oem_id);
> +        strncpy(std->oem_id, hdrs->oem_id, sizeof std->oem_id);
>          ++changed_fields;
>      }
>      if (hdrs->has_oem_table_id) {
> -        strncpy(ext_hdr->oem_table_id, hdrs->oem_table_id,
> -                sizeof ext_hdr->oem_table_id);
> +        strncpy(std->oem_table_id, hdrs->oem_table_id,
> +                sizeof std->oem_table_id);
>          ++changed_fields;
>      }
>      if (hdrs->has_oem_rev) {
> -        ext_hdr->oem_revision = cpu_to_le32(hdrs->oem_rev);
> +        std->oem_revision = cpu_to_le32(hdrs->oem_rev);
>          ++changed_fields;
>      }
>      if (hdrs->has_asl_compiler_id) {
> -        strncpy(ext_hdr->asl_compiler_id, hdrs->asl_compiler_id,
> -                sizeof ext_hdr->asl_compiler_id);
> +        strncpy(std->asl_compiler_id, hdrs->asl_compiler_id,
> +                sizeof std->asl_compiler_id);
>          ++changed_fields;
>      }
>      if (hdrs->has_asl_compiler_rev) {
> -        ext_hdr->asl_compiler_revision = cpu_to_le32(hdrs->asl_compiler_rev);
> +        std->asl_compiler_revision = cpu_to_le32(hdrs->asl_compiler_rev);
>          ++changed_fields;
>      }
>  
> @@ -225,8 +219,8 @@ static void acpi_table_install(const char unsigned *blob, size_t bloblen,
>      }
>  
>      /* recalculate checksum */
> -    ext_hdr->checksum = acpi_checksum((const char unsigned *)ext_hdr +
> -                                      ACPI_TABLE_PFX_SIZE, acpi_payload_size);
> +    std->checksum = acpi_checksum((const char unsigned *)std,
> +                                  acpi_payload_size);
>  }
>  
>  void acpi_table_add(const QemuOpts *opts, Error **errp)
> -- 
> 1.7.1