From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:40233) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1abkUK-0000OL-6s for qemu-devel@nongnu.org; Fri, 04 Mar 2016 02:49:29 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1abkUJ-00012v-6W for qemu-devel@nongnu.org; Fri, 04 Mar 2016 02:49:28 -0500 Received: from mx1.redhat.com ([209.132.183.28]:59701) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1abkUJ-00012K-25 for qemu-devel@nongnu.org; Fri, 04 Mar 2016 02:49:27 -0500 Date: Fri, 4 Mar 2016 09:49:23 +0200 From: "Michael S. Tsirkin" Message-ID: <1457077710-17678-5-git-send-email-mst@redhat.com> References: <1457077710-17678-1-git-send-email-mst@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1457077710-17678-1-git-send-email-mst@redhat.com> Subject: [Qemu-devel] [PULL 04/16] acpi: add build_append_named_dword, returning an offset in buffer List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Peter Maydell , Xiao Guangrong , Igor Mammedov This is a very limited form of support for runtime patching - similar in functionality to what we can do with ACPI_EXTRACT macros in python, but implemented in C. This is to allow ACPI code direct access to data tables - which is exactly what DataTableRegion is there for, except no known windows release so far implements DataTableRegion. Signed-off-by: Michael S. Tsirkin Signed-off-by: Xiao Guangrong Reviewed-by: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin --- include/hw/acpi/aml-build.h | 3 +++ hw/acpi/aml-build.c | 28 ++++++++++++++++++++++++++++ 2 files changed, 31 insertions(+) diff --git a/include/hw/acpi/aml-build.h b/include/hw/acpi/aml-build.h index b16017e..66f48ec 100644 --- a/include/hw/acpi/aml-build.h +++ b/include/hw/acpi/aml-build.h @@ -368,4 +368,7 @@ void build_rsdt(GArray *table_data, GArray *linker, GArray *table_offsets, const char *oem_id, const char *oem_table_id); +int +build_append_named_dword(GArray *array, const char *name_format, ...); + #endif diff --git a/hw/acpi/aml-build.c b/hw/acpi/aml-build.c index f26fa26..ab89ca6 100644 --- a/hw/acpi/aml-build.c +++ b/hw/acpi/aml-build.c @@ -258,6 +258,34 @@ static void build_append_int(GArray *table, uint64_t value) } } +/* + * Build NAME(XXXX, 0x00000000) where 0x00000000 is encoded as a dword, + * and return the offset to 0x00000000 for runtime patching. + * + * Warning: runtime patching is best avoided. Only use this as + * a replacement for DataTableRegion (for guests that don't + * support it). + */ +int +build_append_named_dword(GArray *array, const char *name_format, ...) +{ + int offset; + va_list ap; + + build_append_byte(array, 0x08); /* NameOp */ + va_start(ap, name_format); + build_append_namestringv(array, name_format, ap); + va_end(ap); + + build_append_byte(array, 0x0C); /* DWordPrefix */ + + offset = array->len; + build_append_int_noprefix(array, 0x00000000, 4); + assert(array->len == offset + 4); + + return offset; +} + static GPtrArray *alloc_list; static Aml *aml_alloc(void) -- MST