s390/ap/zcrypt: notify userspace with online, config and mode info

This patch brings 3 reworked/new uevent changes:
* All AP uevents caused by an ap card or queue device now carry an
  additional uevent env value MODE=<accel|cca|ep11>. Here is an
  example:
    KERNEL[1267.301292] add	 /devices/ap/card0a (ap)
    ACTION=add
    DEVPATH=/devices/ap/card0a
    SUBSYSTEM=ap
    DEVTYPE=ap_card
    DEV_TYPE=000D
    MODALIAS=ap:t0D
    MODE=ep11			 <- this is new
    SEQNUM=1095
  This is true for bind, unbind, add, remove, and change uevents
  related to ap card or ap queue devices.
* On a change of the soft online attribute on a zcrypt queue or card
  device a new CHANGE uevent is sent with an env value ONLINE=<0|1>.
  Example uevent:
    KERNEL[613.067531] change	/devices/ap/card09/09.0011 (ap)
    ACTION=change
    DEVPATH=/devices/ap/card09/09.0011
    SUBSYSTEM=ap
    ONLINE=0			<- this is new
    DEVTYPE=ap_queue
    DRIVER=cex4queue
    MODE=cca
    SEQNUM=1070
- On a change of the config state of an zcrypt card device a new
  CHANGE uevent is sent with an env value CONFIG=<0|1>.
  Example uevent:
    KERNEL[876.258680] change	/devices/ap/card09 (ap)
    ACTION=change
    DEVPATH=/devices/ap/card09
    SUBSYSTEM=ap
    CONFIG=0			<- this is new
    DEVTYPE=ap_card
    DRIVER=cex4card
    DEV_TYPE=000D
    MODALIAS=ap:t0D
    MODE=cca
    SEQNUM=1073
  Setting a card config on/off causes the dependent queue devices to
  follow the config state change and thus uevents informing about the
  config state change for the queue devices are also emitted.
Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Reviewed-by: Ingo Franzki <ifranzki@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

drivers/s390/crypto/ap_bus.c

@@ -587,22 +587,47 @@ static int ap_bus_match(struct device *dev, struct device_driver *drv)
  */
 static int ap_uevent(struct device *dev, struct kobj_uevent_env *env)
 {
-	int rc;
+	int rc = 0;
 	struct ap_device *ap_dev = to_ap_dev(dev);
 
 	/* Uevents from ap bus core don't need extensions to the env */
 	if (dev == ap_root_device)
 		return 0;
 
-	/* Set up DEV_TYPE environment variable. */
-	rc = add_uevent_var(env, "DEV_TYPE=%04X", ap_dev->device_type);
-	if (rc)
-		return rc;
+	if (is_card_dev(dev)) {
+		struct ap_card *ac = to_ap_card(&ap_dev->device);
 
-	/* Add MODALIAS= */
-	rc = add_uevent_var(env, "MODALIAS=ap:t%02X", ap_dev->device_type);
-	if (rc)
-		return rc;
+		/* Set up DEV_TYPE environment variable. */
+		rc = add_uevent_var(env, "DEV_TYPE=%04X", ap_dev->device_type);
+		if (rc)
+			return rc;
+		/* Add MODALIAS= */
+		rc = add_uevent_var(env, "MODALIAS=ap:t%02X", ap_dev->device_type);
+		if (rc)
+			return rc;
+
+		/* Add MODE=<accel|cca|ep11> */
+		if (ap_test_bit(&ac->functions, AP_FUNC_ACCEL))
+			rc = add_uevent_var(env, "MODE=accel");
+		else if (ap_test_bit(&ac->functions, AP_FUNC_COPRO))
+			rc = add_uevent_var(env, "MODE=cca");
+		else if (ap_test_bit(&ac->functions, AP_FUNC_EP11))
+			rc = add_uevent_var(env, "MODE=ep11");
+		if (rc)
+			return rc;
+	} else {
+		struct ap_queue *aq = to_ap_queue(&ap_dev->device);
+
+		/* Add MODE=<accel|cca|ep11> */
+		if (ap_test_bit(&aq->card->functions, AP_FUNC_ACCEL))
+			rc = add_uevent_var(env, "MODE=accel");
+		else if (ap_test_bit(&aq->card->functions, AP_FUNC_COPRO))
+			rc = add_uevent_var(env, "MODE=cca");
+		else if (ap_test_bit(&aq->card->functions, AP_FUNC_EP11))
+			rc = add_uevent_var(env, "MODE=ep11");
+		if (rc)
+			return rc;
+	}
 
 	return 0;
 }
@@ -624,6 +649,28 @@ static void ap_send_bindings_complete_uevent(void)
 	kobject_uevent_env(&ap_root_device->kobj, KOBJ_CHANGE, envp);
 }
 
+void ap_send_config_uevent(struct ap_device *ap_dev, bool cfg)
+{
+	char buf[16];
+	char *envp[] = { buf, NULL };
+
+	snprintf(buf, sizeof(buf), "CONFIG=%d", cfg ? 1 : 0);
+
+	kobject_uevent_env(&ap_dev->device.kobj, KOBJ_CHANGE, envp);
+}
+EXPORT_SYMBOL(ap_send_config_uevent);
+
+void ap_send_online_uevent(struct ap_device *ap_dev, int online)
+{
+	char buf[16];
+	char *envp[] = { buf, NULL };
+
+	snprintf(buf, sizeof(buf), "ONLINE=%d", online ? 1 : 0);
+
+	kobject_uevent_env(&ap_dev->device.kobj, KOBJ_CHANGE, envp);
+}
+EXPORT_SYMBOL(ap_send_online_uevent);
+
 /*
  * calc # of bound APQNs
  */
@@ -1546,6 +1593,7 @@ static inline void ap_scan_domains(struct ap_card *ac)
 			spin_unlock_bh(&aq->lock);
 			AP_DBF_INFO("%s(%d,%d) queue device config off\n",
 				    __func__, ac->id, dom);
+			ap_send_config_uevent(&aq->ap_dev, aq->config);
 			/* 'receive' pending messages with -EAGAIN */
 			ap_flush_queue(aq);
 			goto put_dev_and_continue;
@@ -1560,6 +1608,7 @@ static inline void ap_scan_domains(struct ap_card *ac)
 			spin_unlock_bh(&aq->lock);
 			AP_DBF_INFO("%s(%d,%d) queue device config on\n",
 				    __func__, ac->id, dom);
+			ap_send_config_uevent(&aq->ap_dev, aq->config);
 			goto put_dev_and_continue;
 		}
 		/* handle other error states */
@@ -1669,12 +1718,13 @@ static inline void ap_scan_adapter(int ap)
 				ac->config = false;
 				AP_DBF_INFO("%s(%d) card device config off\n",
 					    __func__, ap);
-
+				ap_send_config_uevent(&ac->ap_dev, ac->config);
 			}
 			if (!decfg && !ac->config) {
 				ac->config = true;
 				AP_DBF_INFO("%s(%d) card device config on\n",
 					    __func__, ap);
+				ap_send_config_uevent(&ac->ap_dev, ac->config);
 			}
 		}
 	}

drivers/s390/crypto/ap_bus.h

@@ -362,4 +362,7 @@ int ap_parse_mask_str(const char *str,
  */
 int ap_wait_init_apqn_bindings_complete(unsigned long timeout);
 
+void ap_send_config_uevent(struct ap_device *ap_dev, bool cfg);
+void ap_send_online_uevent(struct ap_device *ap_dev, int online);
+
 #endif /* _AP_BUS_H_ */

drivers/s390/crypto/ap_card.c

@@ -167,6 +167,8 @@ static ssize_t config_store(struct device *dev,
 
 	ac->config = cfg ? true : false;
 
+	ap_send_config_uevent(&ac->ap_dev, ac->config);
+
 	return count;
 }
 

drivers/s390/crypto/zcrypt_api.h

@@ -145,7 +145,7 @@ void zcrypt_queue_get(struct zcrypt_queue *);
 int zcrypt_queue_put(struct zcrypt_queue *);
 int zcrypt_queue_register(struct zcrypt_queue *);
 void zcrypt_queue_unregister(struct zcrypt_queue *);
-void zcrypt_queue_force_online(struct zcrypt_queue *, int);
+bool zcrypt_queue_force_online(struct zcrypt_queue *zq, int online);
 
 int zcrypt_rng_device_add(void);
 void zcrypt_rng_device_remove(void);

drivers/s390/crypto/zcrypt_card.c

@@ -64,7 +64,8 @@ static ssize_t online_store(struct device *dev,
 	struct ap_card *ac = to_ap_card(dev);
 	struct zcrypt_card *zc = ac->private;
 	struct zcrypt_queue *zq;
-	int online, id;
+	int online, id, i = 0, maxzqs = 0;
+	struct zcrypt_queue **zq_uelist = NULL;
 
 	if (sscanf(buf, "%d\n", &online) != 1 || online < 0 || online > 1)
 		return -EINVAL;
@@ -77,10 +78,35 @@ static ssize_t online_store(struct device *dev,
 
 	ZCRYPT_DBF(DBF_INFO, "card=%02x online=%d\n", id, online);
 
+	ap_send_online_uevent(&ac->ap_dev, online);
+
 	spin_lock(&zcrypt_list_lock);
+	/*
+	 * As we are in atomic context here, directly sending uevents
+	 * does not work. So collect the zqueues in a dynamic array
+	 * and process them after zcrypt_list_lock release. As we get/put
+	 * the zqueue objects, we make sure they exist after lock release.
+	 */
+	list_for_each_entry(zq, &zc->zqueues, list)
+		maxzqs++;
+	if (maxzqs > 0)
+		zq_uelist = kcalloc(maxzqs + 1, sizeof(zq), GFP_ATOMIC);
 	list_for_each_entry(zq, &zc->zqueues, list)
-		zcrypt_queue_force_online(zq, online);
+		if (zcrypt_queue_force_online(zq, online))
+			if (zq_uelist) {
+				zcrypt_queue_get(zq);
+				zq_uelist[i++] = zq;
+			}
 	spin_unlock(&zcrypt_list_lock);
+	if (zq_uelist) {
+		for (i = 0; zq_uelist[i]; i++) {
+			zq = zq_uelist[i];
+			ap_send_online_uevent(&zq->queue->ap_dev, online);
+			zcrypt_queue_put(zq);
+		}
+		kfree(zq_uelist);
+	}
+
 	return count;
 }
 

drivers/s390/crypto/zcrypt_msgtype50.c

@@ -375,6 +375,7 @@ static int convert_type80(struct zcrypt_queue *zq,
 			       AP_QID_CARD(zq->queue->qid),
 			       AP_QID_QUEUE(zq->queue->qid),
 			       t80h->code);
+		ap_send_online_uevent(&zq->queue->ap_dev, zq->online);
 		return -EAGAIN;
 	}
 	if (zq->zcard->user_space_type == ZCRYPT_CEX2A)
@@ -412,6 +413,7 @@ static int convert_response_cex2a(struct zcrypt_queue *zq,
 			       AP_QID_CARD(zq->queue->qid),
 			       AP_QID_QUEUE(zq->queue->qid),
 			       (int) rtype);
+		ap_send_online_uevent(&zq->queue->ap_dev, zq->online);
 		return -EAGAIN;
 	}
 }

drivers/s390/crypto/zcrypt_msgtype6.c

@@ -675,6 +675,7 @@ static int convert_type86_ica(struct zcrypt_queue *zq,
 			       AP_QID_CARD(zq->queue->qid),
 			       AP_QID_QUEUE(zq->queue->qid),
 			       (int) service_rc, (int) service_rs);
+		ap_send_online_uevent(&zq->queue->ap_dev, zq->online);
 		return -EAGAIN;
 	}
 	data = msg->text;
@@ -820,6 +821,7 @@ static int convert_response_ica(struct zcrypt_queue *zq,
 			       AP_QID_CARD(zq->queue->qid),
 			       AP_QID_QUEUE(zq->queue->qid),
 			       (int) msg->hdr.type);
+		ap_send_online_uevent(&zq->queue->ap_dev, zq->online);
 		return -EAGAIN;
 	}
 }
@@ -854,6 +856,7 @@ static int convert_response_xcrb(bool userspace, struct zcrypt_queue *zq,
 			       AP_QID_CARD(zq->queue->qid),
 			       AP_QID_QUEUE(zq->queue->qid),
 			       (int) msg->hdr.type);
+		ap_send_online_uevent(&zq->queue->ap_dev, zq->online);
 		return -EAGAIN;
 	}
 }
@@ -883,6 +886,7 @@ static int convert_response_ep11_xcrb(bool userspace, struct zcrypt_queue *zq,
 			       AP_QID_CARD(zq->queue->qid),
 			       AP_QID_QUEUE(zq->queue->qid),
 			       (int) msg->hdr.type);
+		ap_send_online_uevent(&zq->queue->ap_dev, zq->online);
 		return -EAGAIN;
 	}
 }
@@ -913,6 +917,7 @@ static int convert_response_rng(struct zcrypt_queue *zq,
 			       AP_QID_CARD(zq->queue->qid),
 			       AP_QID_QUEUE(zq->queue->qid),
 			       (int) msg->hdr.type);
+		ap_send_online_uevent(&zq->queue->ap_dev, zq->online);
 		return -EAGAIN;
 	}
 }

drivers/s390/crypto/zcrypt_queue.c

@@ -70,6 +70,8 @@ static ssize_t online_store(struct device *dev,
 		   AP_QID_QUEUE(zq->queue->qid),
 		   online);
 
+	ap_send_online_uevent(&aq->ap_dev, online);
+
 	if (!online)
 		ap_flush_queue(zq->queue);
 	return count;
@@ -98,11 +100,15 @@ static const struct attribute_group zcrypt_queue_attr_group = {
 	.attrs = zcrypt_queue_attrs,
 };
 
-void zcrypt_queue_force_online(struct zcrypt_queue *zq, int online)
+bool zcrypt_queue_force_online(struct zcrypt_queue *zq, int online)
 {
-	zq->online = online;
-	if (!online)
-		ap_flush_queue(zq->queue);
+	if (!!zq->online != !!online) {
+		zq->online = online;
+		if (!online)
+			ap_flush_queue(zq->queue);
+		return true;
+	}
+	return false;
 }
 
 struct zcrypt_queue *zcrypt_queue_alloc(size_t max_response_size)