s390/ap: add card/queue deconfig state

This patch adds a new config state to the ap card and queue
devices. This state reflects the response code
0x03 "AP deconfigured" on TQAP invocation and is tracked with
every ap bus scan.

Together with this new state now a card/queue device which
is 'deconfigured' is not disposed any more. However, for backward
compatibility the online state now needs to take this state into
account. So a card/queue is offline when the device is not configured.
Furthermore a device can't get switched from offline to online state
when not configured.

The config state is shown in sysfs at
  /sys/devices/ap/cardxx/config
for the card and
  /sys/devices/ap/cardxx/xx.yyyy/config
for each queue within each card.
It is a read-only attribute reflecting the negation of the
'AP deconfig' state as it is noted in the AP documents.

Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

1 files changed, 246 insertions, 118 deletions

diff --git a/drivers/s390/crypto/ap_bus.c b/drivers/s390/crypto/ap_bus.c
index 6d61e89c5984..485cbfcbf06e 100644
--- a/drivers/s390/crypto/ap_bus.c
+++ b/drivers/s390/crypto/ap_bus.c
@@ -307,7 +307,7 @@ EXPORT_SYMBOL(ap_test_config_ctrl_domain);
  * false otherwise.
  */
 static bool ap_queue_info(ap_qid_t qid, int *q_type,
-			  unsigned int *q_fac, int *q_depth)
+			  unsigned int *q_fac, int *q_depth, bool *q_decfg)
 {
 	struct ap_queue_status status;
 	unsigned long info = 0;
@@ -322,6 +322,9 @@ static bool ap_queue_info(ap_qid_t qid, int *q_type,
 	switch (status.response_code) {
 	case AP_RESPONSE_NORMAL:
 	case AP_RESPONSE_RESET_IN_PROGRESS:
+	case AP_RESPONSE_DECONFIGURED:
+	case AP_RESPONSE_CHECKSTOPPED:
+	case AP_RESPONSE_BUSY:
 		/*
 		 * According to the architecture in all these cases the
 		 * info should be filled. All bits 0 is not possible as
@@ -332,6 +335,7 @@ static bool ap_queue_info(ap_qid_t qid, int *q_type,
 		*q_type = (int)((info >> 24) & 0xff);
 		*q_fac = (unsigned int)(info >> 32);
 		*q_depth = (int)(info & 0xff);
+		*q_decfg = status.response_code == AP_RESPONSE_DECONFIGURED;
 		switch (*q_type) {
 			/* For CEX2 and CEX3 the available functions
 			 * are not reflected by the facilities bits.
@@ -1290,154 +1294,278 @@ static int __match_queue_device_with_queue_id(struct device *dev, const void *da
 
 /*
  * Helper function for ap_scan_bus().
- * Does the scan bus job for the given adapter id.
+ * Remove card device and associated queue devices.
+ */
+static inline void ap_scan_rm_card_dev_and_queue_devs(struct ap_card *ac)
+{
+	bus_for_each_dev(&ap_bus_type, NULL,
+			 (void *)(long) ac->id,
+			 __ap_queue_devices_with_id_unregister);
+	device_unregister(&ac->ap_dev.device);
+}
+
+/*
+ * Helper function for ap_scan_bus().
+ * Does the scan bus job for all the domains within
+ * a valid adapter given by an ap_card ptr.
  */
-static void _ap_scan_bus_adapter(int id)
+static inline void ap_scan_domains(struct ap_card *ac)
 {
-	bool broken;
+	bool decfg;
 	ap_qid_t qid;
 	unsigned int func;
-	struct ap_card *ac;
 	struct device *dev;
 	struct ap_queue *aq;
+	int rc, dom, depth, type;
+
+	/*
+	 * Go through the configuration for the domains and compare them
+	 * to the existing queue devices. Also take care of the config
+	 * and error state for the queue devices.
+	 */
+
+	for (dom = 0; dom <= ap_max_domain_id; dom++) {
+		qid = AP_MKQID(ac->id, dom);
+		dev = bus_find_device(&ap_bus_type, NULL,
+				      (void *)(long) qid,
+				      __match_queue_device_with_qid);
+		aq = dev ? to_ap_queue(dev) : NULL;
+		if (!ap_test_config_usage_domain(dom)) {
+			if (dev) {
+				AP_DBF_INFO("%s(%d,%d) not in config any more, rm queue device\n",
+					    __func__, ac->id, dom);
+				device_unregister(dev);
+				put_device(dev);
+			}
+			continue;
+		}
+		/* domain is valid, get info from this APQN */
+		if (!ap_queue_info(qid, &type, &func, &depth, &decfg)) {
+			if (aq) {
+				AP_DBF_INFO(
+					"%s(%d,%d) ap_queue_info() not successful, rm queue device\n",
+					__func__, ac->id, dom);
+				device_unregister(dev);
+				put_device(dev);
+			}
+			continue;
+		}
+		/* if no queue device exists, create a new one */
+		if (!aq) {
+			aq = ap_queue_create(qid, ac->ap_dev.device_type);
+			if (!aq) {
+				AP_DBF_WARN("%s(%d,%d) ap_queue_create() failed\n",
+					    __func__, ac->id, dom);
+				continue;
+			}
+			aq->card = ac;
+			aq->config = !decfg;
+			dev = &aq->ap_dev.device;
+			dev->bus = &ap_bus_type;
+			dev->parent = &ac->ap_dev.device;
+			dev_set_name(dev, "%02x.%04x", ac->id, dom);
+			/* register queue device */
+			rc = device_register(dev);
+			if (rc) {
+				AP_DBF_WARN("%s(%d,%d) device_register() failed\n",
+					    __func__, ac->id, dom);
+				goto put_dev_and_continue;
+			}
+			if (decfg)
+				AP_DBF_INFO("%s(%d,%d) new (decfg) queue device created\n",
+					    __func__, ac->id, dom);
+			else
+				AP_DBF_INFO("%s(%d,%d) new queue device created\n",
+					    __func__, ac->id, dom);
+			goto put_dev_and_continue;
+		}
+		/* Check config state on the already existing queue device */
+		spin_lock_bh(&aq->lock);
+		if (decfg && aq->config) {
+			/* config off this queue device */
+			aq->config = false;
+			if (aq->dev_state > AP_DEV_STATE_UNINITIATED) {
+				aq->dev_state = AP_DEV_STATE_ERROR;
+				aq->last_err_rc = AP_RESPONSE_DECONFIGURED;
+			}
+			spin_unlock_bh(&aq->lock);
+			AP_DBF_INFO("%s(%d,%d) queue device config off\n",
+				    __func__, ac->id, dom);
+			/* 'receive' pending messages with -EAGAIN */
+			ap_flush_queue(aq);
+			goto put_dev_and_continue;
+		}
+		if (!decfg && !aq->config) {
+			/* config on this queue device */
+			aq->config = true;
+			if (aq->dev_state > AP_DEV_STATE_UNINITIATED) {
+				aq->dev_state = AP_DEV_STATE_OPERATING;
+				aq->sm_state = AP_SM_STATE_RESET_START;
+			}
+			spin_unlock_bh(&aq->lock);
+			AP_DBF_INFO("%s(%d,%d) queue device config on\n",
+				    __func__, ac->id, dom);
+			goto put_dev_and_continue;
+		}
+		/* handle other error states */
+		if (!decfg && aq->dev_state == AP_DEV_STATE_ERROR) {
+			spin_unlock_bh(&aq->lock);
+			/* 'receive' pending messages with -EAGAIN */
+			ap_flush_queue(aq);
+			/* re-init (with reset) the queue device */
+			ap_queue_init_state(aq);
+			AP_DBF_INFO("%s(%d,%d) queue device reinit enforced\n",
+				    __func__, ac->id, dom);
+			goto put_dev_and_continue;
+		}
+		spin_unlock_bh(&aq->lock);
+put_dev_and_continue:
+		put_device(dev);
+	}
+}
+
+/*
+ * Helper function for ap_scan_bus().
+ * Does the scan bus job for the given adapter id.
+ */
+static inline void ap_scan_adapter(int ap)
+{
+	bool decfg;
+	ap_qid_t qid;
+	unsigned int func;
+	struct device *dev;
+	struct ap_card *ac;
 	int rc, dom, depth, type, comp_type;
 
-	/* check if there is a card device registered with this id */
+	/* Is there currently a card device for this adapter ? */
 	dev = bus_find_device(&ap_bus_type, NULL,
-			      (void *)(long) id,
+			      (void *)(long) ap,
 			      __match_card_device_with_id);
 	ac = dev ? to_ap_card(dev) : NULL;
-	if (!ap_test_config_card_id(id)) {
-		if (dev) {
-			/* Card device has been removed from configuration */
-			bus_for_each_dev(&ap_bus_type, NULL,
-					 (void *)(long) id,
-					 __ap_queue_devices_with_id_unregister);
-			device_unregister(dev);
+
+	/* Adapter not in configuration ? */
+	if (!ap_test_config_card_id(ap)) {
+		if (ac) {
+			AP_DBF_INFO("%s(%d) ap not in config any more, rm card and queue devices\n",
+				    __func__, ap);
+			ap_scan_rm_card_dev_and_queue_devs(ac);
 			put_device(dev);
 		}
 		return;
 	}
 
 	/*
-	 * This card id is enabled in the configuration. If we already have
-	 * a card device with this id, check if type and functions are still
-	 * the very same. Also verify that at least one queue is available.
+	 * Adapter ap is valid in the current configuration. So do some checks:
+	 * If no card device exists, build one. If a card device exists, check
+	 * for type and functions changed. For all this we need to find a valid
+	 * APQN first.
 	 */
-	if (ac) {
-		/* find the first valid queue */
-		for (dom = 0; dom < AP_DOMAINS; dom++) {
-			qid = AP_MKQID(id, dom);
-			if (ap_queue_info(qid, &type, &func, &depth))
+
+	for (dom = 0; dom <= ap_max_domain_id; dom++)
+		if (ap_test_config_usage_domain(dom)) {
+			qid = AP_MKQID(ap, dom);
+			if (ap_queue_info(qid, &type, &func, &depth, &decfg))
 				break;
 		}
-		broken = false;
-		if (dom >= AP_DOMAINS) {
-			/* no accessible queue on this card */
-			broken = true;
-		} else if (ac->raw_hwtype != type) {
-			/* card type has changed */
-			AP_DBF_INFO("card=%02x type changed.\n", id);
-			broken = true;
-		} else if (ac->functions != func) {
-			/* card functions have changed */
-			AP_DBF_INFO("card=%02x functions changed.\n", id);
-			broken = true;
+	if (dom > ap_max_domain_id) {
+		/* Could not find a valid APQN for this adapter */
+		if (ac) {
+			AP_DBF_INFO(
+				"%s(%d) no type info (no APQN found), rm card and queue devices\n",
+				__func__, ap);
+			ap_scan_rm_card_dev_and_queue_devs(ac);
+			put_device(dev);
+		} else {
+			AP_DBF_DBG("%s(%d) no type info (no APQN found), ignored\n",
+				   __func__, ap);
 		}
-		if (broken) {
-			/* unregister card device and associated queues */
-			bus_for_each_dev(&ap_bus_type, NULL,
-					 (void *)(long) id,
-					 __ap_queue_devices_with_id_unregister);
-			device_unregister(dev);
+		return;
+	}
+	if (!type) {
+		/* No apdater type info available, an unusable adapter */
+		if (ac) {
+			AP_DBF_INFO("%s(%d) no valid type (0) info, rm card and queue devices\n",
+				    __func__, ap);
+			ap_scan_rm_card_dev_and_queue_devs(ac);
 			put_device(dev);
-			/* go back if there is no valid queue on this card */
-			if (dom >= AP_DOMAINS)
-				return;
-			ac = NULL;
+		} else {
+			AP_DBF_DBG("%s(%d) no valid type (0) info, ignored\n",
+				   __func__, ap);
 		}
+		return;
 	}
 
-	/*
-	 * Go through all possible queue ids. Check and maybe create or release
-	 * queue devices for this card. If there exists no card device yet,
-	 * create a card device also.
-	 */
-	for (dom = 0; dom < AP_DOMAINS; dom++) {
-		qid = AP_MKQID(id, dom);
-		dev = bus_find_device(&ap_bus_type, NULL,
-				      (void *)(long) qid,
-				      __match_queue_device_with_qid);
-		aq = dev ? to_ap_queue(dev) : NULL;
-		if (!ap_test_config_usage_domain(dom)) {
-			if (dev) {
-				/* Queue device exists but has been
-				 * removed from configuration.
-				 */
-				device_unregister(dev);
-				put_device(dev);
-			}
-			continue;
-		}
-		/* try to fetch infos about this queue */
-		broken = !ap_queue_info(qid, &type, &func, &depth);
-		if (dev) {
-			if (!broken) {
-				spin_lock_bh(&aq->lock);
-				broken = aq->dev_state == AP_DEV_STATE_ERROR;
-				spin_unlock_bh(&aq->lock);
+	if (ac) {
+		/* Check APQN against existing card device for changes */
+		if (ac->raw_hwtype != type) {
+			AP_DBF_INFO("%s(%d) hwtype %d changed, rm card and queue devices\n",
+				    __func__, ap, type);
+			ap_scan_rm_card_dev_and_queue_devs(ac);
+			put_device(dev);
+			ac = NULL;
+		} else if (ac->functions != func) {
+			AP_DBF_INFO("%s(%d) functions 0x%08x changed, rm card and queue devices\n",
+				    __func__, ap, type);
+			ap_scan_rm_card_dev_and_queue_devs(ac);
+			put_device(dev);
+			ac = NULL;
+		} else {
+			if (decfg && ac->config) {
+				ac->config = false;
+				AP_DBF_INFO("%s(%d) card device config off\n",
+					    __func__, ap);
+
 			}
-			if (broken) {
-				/* Remove broken device */
-				AP_DBF_DBG("removing broken queue=%02x.%04x\n",
-					   id, dom);
-				device_unregister(dev);
+			if (!decfg && !ac->config) {
+				ac->config = true;
+				AP_DBF_INFO("%s(%d) card device config on\n",
+					    __func__, ap);
 			}
-			put_device(dev);
-			continue;
 		}
-		if (broken)
-			continue;
-		/* a new queue device is needed, check out comp type */
+	}
+
+	if (!ac) {
+		/* Build a new card device */
 		comp_type = ap_get_compatible_type(qid, type, func);
-		if (!comp_type)
-			continue;
-		/* maybe a card device needs to be created first */
+		if (!comp_type) {
+			AP_DBF_WARN("%s(%d) type %d, can't get compatibility type\n",
+				    __func__, ap, type);
+			return;
+		}
+		ac = ap_card_create(ap, depth, type, comp_type, func);
 		if (!ac) {
-			ac = ap_card_create(id, depth, type, comp_type, func);
-			if (!ac)
-				continue;
-			ac->ap_dev.device.bus = &ap_bus_type;
-			ac->ap_dev.device.parent = ap_root_device;
-			dev_set_name(&ac->ap_dev.device, "card%02x", id);
-			/* Register card device with AP bus */
-			rc = device_register(&ac->ap_dev.device);
-			if (rc) {
-				put_device(&ac->ap_dev.device);
-				ac = NULL;
-				break;
-			}
-			/* get it and thus adjust reference counter */
-			get_device(&ac->ap_dev.device);
+			AP_DBF_WARN("%s(%d) ap_card_create() failed\n",
+				    __func__, ap);
+			return;
 		}
-		/* now create the new queue device */
-		aq = ap_queue_create(qid, comp_type);
-		if (!aq)
-			continue;
-		aq->card = ac;
-		aq->ap_dev.device.bus = &ap_bus_type;
-		aq->ap_dev.device.parent = &ac->ap_dev.device;
-		dev_set_name(&aq->ap_dev.device, "%02x.%04x", id, dom);
-		/* Register queue device */
-		rc = device_register(&aq->ap_dev.device);
+		ac->config = !decfg;
+		dev = &ac->ap_dev.device;
+		dev->bus = &ap_bus_type;
+		dev->parent = ap_root_device;
+		dev_set_name(dev, "card%02x", ap);
+		/* Register the new card device with AP bus */
+		rc = device_register(dev);
 		if (rc) {
-			put_device(&aq->ap_dev.device);
-			continue;
+			AP_DBF_WARN("%s(%d) device_register() failed\n",
+				    __func__, ap);
+			put_device(dev);
+			return;
 		}
-	} /* end domain loop */
+		/* get it and thus adjust reference counter */
+		get_device(dev);
+		if (decfg)
+			AP_DBF_INFO("%s(%d) new (decfg) card device type=%d func=0x%08x created\n",
+				    __func__, ap, type, func);
+		else
+			AP_DBF_INFO("%s(%d) new card device type=%d func=0x%08x created\n",
+				    __func__, ap, type, func);
+	}
+
+	/* Verify the domains and the queue devices for this card */
+	ap_scan_domains(ac);
 
-	if (ac)
-		put_device(&ac->ap_dev.device);
+	/* release the card device */
+	put_device(&ac->ap_dev.device);
 }
 
 /**
@@ -1446,7 +1574,7 @@ static void _ap_scan_bus_adapter(int id)
  */
 static void ap_scan_bus(struct work_struct *unused)
 {
-	int id;
+	int ap;
 
 	ap_fetch_qci_info(ap_qci_info);
 	ap_select_domain();
@@ -1454,8 +1582,8 @@ static void ap_scan_bus(struct work_struct *unused)
 	AP_DBF_DBG("%s running\n", __func__);
 
 	/* loop over all possible adapters */
-	for (id = 0; id < AP_DEVICES; id++)
-		_ap_scan_bus_adapter(id);
+	for (ap = 0; ap <= ap_max_adapter_id; ap++)
+		ap_scan_adapter(ap);
 
 	/* check if there is at least one queue available with default domain */
 	if (ap_domain_index >= 0) {