crypto: qat - Use static_assert() to check struct sizes

JIRA: https://issues.redhat.com/browse/RHEL-52749
Upstream Status: merged into the linux.git

commit 8caa061
Author: Gustavo A. R. Silva <gustavoars@kernel.org>
Date:   Thu Aug 8 16:05:26 2024 -0600

    crypto: qat - Use static_assert() to check struct sizes

    Commit 140e4c8 ("crypto: qat - Avoid -Wflex-array-member-not-at-end
    warnings") introduced tagged `struct qat_alg_buf_list_hdr`. We want to
    ensure that when new members need to be added to the flexible structure,
    they are always included within this tagged struct.

    So, we use `static_assert()` to ensure that the memory layout for
    both the flexible structure and the tagged struct is the same after
    any changes.

    Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
    Acked-by: Giovanni Cabiddu <giovanni.cabiddu@intel.com>
    Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

Signed-off-by: Vladis Dronov <vdronov@redhat.com>

Author: nefigtut

drivers/crypto/intel/qat/qat_common/qat_bl.h

@@ -23,6 +23,8 @@ struct qat_alg_buf_list {
 	);
 	struct qat_alg_buf buffers[];
 } __packed;
+static_assert(offsetof(struct qat_alg_buf_list, buffers) == sizeof(struct qat_alg_buf_list_hdr),
+	      "struct member likely outside of __struct_group()");
 
 struct qat_alg_fixed_buf_list {
 	struct qat_alg_buf_list_hdr sgl_hdr;