[PATCH] s390: Add attestation query information

[PATCH] s390: Add attestation query information

[Steffen Eiden]

We have information about the supported attestation header version
and paf (=  plaintext attestation flag) bits.
Let's expose it via the sysfs files.

Signed-off-by: Steffen Eiden <seiden@linux.ibm.com>
---
 arch/s390/boot/uv.c        |  2 ++
 arch/s390/include/asm/uv.h |  7 ++++++-
 arch/s390/kernel/uv.c      | 20 ++++++++++++++++++++
 3 files changed, 28 insertions(+), 1 deletion(-)

diff --git a/arch/s390/boot/uv.c b/arch/s390/boot/uv.c
index e6be155ab2e5..5e17c657e3d6 100644
--- a/arch/s390/boot/uv.c
+++ b/arch/s390/boot/uv.c
@@ -41,6 +41,8 @@ void uv_query_info(void)
 		uv_info.max_num_sec_conf = uvcb.max_num_sec_conf;
 		uv_info.max_guest_cpu_id = uvcb.max_guest_cpu_id;
 		uv_info.uv_feature_indications = uvcb.uv_feature_indications;
+		uv_info.supp_att_req_hdr_ver = uvcb.supp_att_req_hdr_ver;
+		uv_info.supp_att_pflags = uvcb.supp_att_pflags;
 	}
 
 #ifdef CONFIG_PROTECTED_VIRTUALIZATION_GUEST
diff --git a/arch/s390/include/asm/uv.h b/arch/s390/include/asm/uv.h
index cfea7b77a5b8..99f459c0eacc 100644
--- a/arch/s390/include/asm/uv.h
+++ b/arch/s390/include/asm/uv.h
@@ -110,7 +110,10 @@ struct uv_cb_qui {
 	u8  reserved88[158 - 136];		/* 0x0088 */
 	u16 max_guest_cpu_id;			/* 0x009e */
 	u64 uv_feature_indications;		/* 0x00a0 */
-	u8  reserveda8[200 - 168];		/* 0x00a8 */
+	u8  reserveda8[224 - 168];		/* 0x00a8 */
+	u64 supp_att_req_hdr_ver;		/* 0x00e0 */
+	u64 supp_att_pflags;			/* 0x00e8 */
+	u8 reservedf0[256 - 240];		/* 0x00f0 */
 } __packed __aligned(8);
 
 /* Initialize Ultravisor */
@@ -307,6 +310,8 @@ struct uv_info {
 	unsigned int max_num_sec_conf;
 	unsigned short max_guest_cpu_id;
 	unsigned long uv_feature_indications;
+	unsigned long supp_att_req_hdr_ver;
+	unsigned long supp_att_pflags;
 };
 
 extern struct uv_info uv_info;
diff --git a/arch/s390/kernel/uv.c b/arch/s390/kernel/uv.c
index a5425075dd25..095afd375ad1 100644
--- a/arch/s390/kernel/uv.c
+++ b/arch/s390/kernel/uv.c
@@ -431,12 +431,32 @@ static ssize_t uv_query_max_guest_addr(struct kobject *kobj,
 static struct kobj_attribute uv_query_max_guest_addr_attr =
 	__ATTR(max_address, 0444, uv_query_max_guest_addr, NULL);
 
+static ssize_t uv_query_supp_att_req_hdr_ver(struct kobject *kobj,
+					     struct kobj_attribute *attr, char *page)
+{
+	return scnprintf(page, PAGE_SIZE, "%lx\n", uv_info.supp_att_req_hdr_ver);
+}
+
+static struct kobj_attribute uv_query_supp_att_req_hdr_ver_attr =
+	__ATTR(supp_att_req_hdr_ver, 0444, uv_query_supp_att_req_hdr_ver, NULL);
+
+static ssize_t uv_query_supp_att_pflags(struct kobject *kobj,
+					struct kobj_attribute *attr, char *page)
+{
+	return scnprintf(page, PAGE_SIZE, "%lx\n", uv_info.supp_att_pflags);
+}
+
+static struct kobj_attribute uv_query_supp_att_pflags_attr =
+	__ATTR(supp_att_pflags, 0444, uv_query_supp_att_pflags, NULL);
+
 static struct attribute *uv_query_attrs[] = {
 	&uv_query_facilities_attr.attr,
 	&uv_query_feature_indications_attr.attr,
 	&uv_query_max_guest_cpus_attr.attr,
 	&uv_query_max_guest_vms_attr.attr,
 	&uv_query_max_guest_addr_attr.attr,
+	&uv_query_supp_att_req_hdr_ver_attr.attr,
+	&uv_query_supp_att_pflags_attr.attr,
 	NULL,
 };
 
-- 
2.30.2

Re: [PATCH] s390: Add attestation query information

[Heiko Carstens]

On Wed, May 18, 2022 at 09:51:13AM +0000, Steffen Eiden wrote:
> We have information about the supported attestation header version
> and paf (=  plaintext attestation flag) bits.
> Let's expose it via the sysfs files.
> 
> Signed-off-by: Steffen Eiden <seiden@linux.ibm.com>
> ---
>  arch/s390/boot/uv.c        |  2 ++
>  arch/s390/include/asm/uv.h |  7 ++++++-
>  arch/s390/kernel/uv.c      | 20 ++++++++++++++++++++
>  3 files changed, 28 insertions(+), 1 deletion(-)

Please write in the cover-letter *why* this is needed.