s390/ap: exploit new B bit from QCI config info

This patch introduces an update to the ap_config_info
struct which is filled with the QCI subfunction. There
is a new bit apsb (short 'B') showing if the AP secure
bind facility is available. The patch also includes a
simple function ap_sb_available() wrapping this bit test.
Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Reviewed-by: Tony Krowiak <akrowiak@linux.ibm.com>
Reviewed-by: Holger Dengler <dengler@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

arch/s390/include/asm/ap.h

@@ -180,15 +180,16 @@ struct ap_config_info {
 	unsigned int apxa	 : 1;	/* N bit */
 	unsigned int qact	 : 1;	/* C bit */
 	unsigned int rc8a	 : 1;	/* R bit */
-	unsigned char _reserved1 : 4;
-	unsigned char _reserved2[3];
-	unsigned char Na;		/* max # of APs - 1 */
-	unsigned char Nd;		/* max # of Domains - 1 */
-	unsigned char _reserved3[10];
+	unsigned int		 : 4;
+	unsigned int apsb	 : 1;	/* B bit */
+	unsigned int		 : 23;
+	unsigned char na;		/* max # of APs - 1 */
+	unsigned char nd;		/* max # of Domains - 1 */
+	unsigned char _reserved0[10];
 	unsigned int apm[8];		/* AP ID mask */
 	unsigned int aqm[8];		/* AP (usage) queue mask */
 	unsigned int adm[8];		/* AP (control) domain mask */
-	unsigned char _reserved4[16];
+	unsigned char _reserved1[16];
 } __aligned(8);
 
 /**

drivers/s390/crypto/ap_bus.c

@@ -200,6 +200,18 @@ static inline int ap_qact_available(void)
 	return 0;
 }
 
+/*
+ * ap_sb_available(): Test if the AP secure binding facility is available.
+ *
+ * Returns 1 if secure binding facility is available.
+ */
+int ap_sb_available(void)
+{
+	if (ap_qci_info)
+		return ap_qci_info->apsb;
+	return 0;
+}
+
 /*
  * ap_fetch_qci_info(): Fetch cryptographic config info
  *
@@ -248,13 +260,13 @@ static void __init ap_init_qci_info(void)
 	AP_DBF_INFO("%s successful fetched initial qci info\n", __func__);
 
 	if (ap_qci_info->apxa) {
-		if (ap_qci_info->Na) {
-			ap_max_adapter_id = ap_qci_info->Na;
+		if (ap_qci_info->na) {
+			ap_max_adapter_id = ap_qci_info->na;
 			AP_DBF_INFO("%s new ap_max_adapter_id is %d\n",
 				    __func__, ap_max_adapter_id);
 		}
-		if (ap_qci_info->Nd) {
-			ap_max_domain_id = ap_qci_info->Nd;
+		if (ap_qci_info->nd) {
+			ap_max_domain_id = ap_qci_info->nd;
 			AP_DBF_INFO("%s new ap_max_domain_id is %d\n",
 				    __func__, ap_max_domain_id);
 		}

drivers/s390/crypto/ap_bus.h

@@ -296,6 +296,7 @@ void ap_cancel_message(struct ap_queue *aq, struct ap_message *ap_msg);
 void ap_flush_queue(struct ap_queue *aq);
 
 void *ap_airq_ptr(void);
+int ap_sb_available(void);
 void ap_wait(enum ap_sm_wait wait);
 void ap_request_timeout(struct timer_list *t);
 void ap_bus_force_rescan(void);

drivers/s390/crypto/vfio_ap_ops.c

@@ -599,9 +599,9 @@ static int handle_pqap(struct kvm_vcpu *vcpu)
 static void vfio_ap_matrix_init(struct ap_config_info *info,
 				struct ap_matrix *matrix)
 {
-	matrix->apm_max = info->apxa ? info->Na : 63;
-	matrix->aqm_max = info->apxa ? info->Nd : 15;
-	matrix->adm_max = info->apxa ? info->Nd : 15;
+	matrix->apm_max = info->apxa ? info->na : 63;
+	matrix->aqm_max = info->apxa ? info->nd : 15;
+	matrix->adm_max = info->apxa ? info->nd : 15;
 }
 
 static void vfio_ap_mdev_update_guest_apcb(struct ap_matrix_mdev *matrix_mdev)