Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi

Pull SCSI updates from James Bottomley:
 "This is mostly update of the usual drivers: aacraid, ufs, zfcp,
  NCR5380, lpfc, qla2xxx, smartpqi, hisi_sas, target, mpt3sas, pm80xx
  plus a whole load of minor updates and fixes.

  The major core changes are Al Viro's reworking of sg's handling of
  copy to/from user, Ming Lei's removal of the host busy counter to
  avoid contention in the multiqueue case and Damien Le Moal's fixing of
  residual tracking across error handling"

* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (251 commits)
  scsi: bnx2fc: timeout calculation invalid for bnx2fc_eh_abort()
  scsi: target: core: Fix a pr_debug() argument
  scsi: iscsi: Don't send data to unbound connection
  scsi: target: iscsi: Wait for all commands to finish before freeing a session
  scsi: target: core: Release SPC-2 reservations when closing a session
  scsi: target: core: Document target_cmd_size_check()
  scsi: bnx2i: fix potential use after free
  Revert "scsi: qla2xxx: Fix memory leak when sending I/O fails"
  scsi: NCR5380: Add disconnect_mask module parameter
  scsi: NCR5380: Unconditionally clear ICR after do_abort()
  scsi: NCR5380: Call scsi_set_resid() on command completion
  scsi: scsi_debug: num_tgts must be >= 0
  scsi: lpfc: use hdwq assigned cpu for allocation
  scsi: arcmsr: fix indentation issues
  scsi: qla4xxx: fix double free bug
  scsi: pm80xx: Modified the logic to collect fatal dump
  scsi: pm80xx: Tie the interrupt name to the module instance
  scsi: pm80xx: Controller fatal error through sysfs
  scsi: pm80xx: Do not request 12G sas speeds
  scsi: pm80xx: Cleanup command when a reset times out
  ...

12 files changed, 683 insertions, 22 deletions

diff --git a/drivers/s390/scsi/Makefile b/drivers/s390/scsi/Makefile
index 9dda431ec8f3..352056eb0dd1 100644
--- a/drivers/s390/scsi/Makefile
+++ b/drivers/s390/scsi/Makefile
@@ -5,6 +5,6 @@
 
 zfcp-objs := zfcp_aux.o zfcp_ccw.o zfcp_dbf.o zfcp_erp.o \
 	     zfcp_fc.o zfcp_fsf.o zfcp_qdio.o zfcp_scsi.o zfcp_sysfs.o \
-	     zfcp_unit.o
+	     zfcp_unit.o zfcp_diag.o
 
 obj-$(CONFIG_ZFCP) += zfcp.o
diff --git a/drivers/s390/scsi/zfcp_aux.c b/drivers/s390/scsi/zfcp_aux.c
index e390f8c6d5f3..09ec846fe01d 100644
--- a/drivers/s390/scsi/zfcp_aux.c
+++ b/drivers/s390/scsi/zfcp_aux.c
@@ -4,7 +4,7 @@
  *
  * Module interface and handling of zfcp data structures.
  *
- * Copyright IBM Corp. 2002, 2017
+ * Copyright IBM Corp. 2002, 2018
  */
 
 /*
@@ -25,6 +25,7 @@
  *            Martin Petermann
  *            Sven Schuetz
  *            Steffen Maier
+ *	      Benjamin Block
  */
 
 #define KMSG_COMPONENT "zfcp"
@@ -36,6 +37,7 @@
 #include "zfcp_ext.h"
 #include "zfcp_fc.h"
 #include "zfcp_reqlist.h"
+#include "zfcp_diag.h"
 
 #define ZFCP_BUS_ID_SIZE	20
 
@@ -356,6 +358,9 @@ struct zfcp_adapter *zfcp_adapter_enqueue(struct ccw_device *ccw_device)
 
 	adapter->erp_action.adapter = adapter;
 
+	if (zfcp_diag_adapter_setup(adapter))
+		goto failed;
+
 	if (zfcp_qdio_setup(adapter))
 		goto failed;
 
@@ -402,6 +407,9 @@ struct zfcp_adapter *zfcp_adapter_enqueue(struct ccw_device *ccw_device)
 			       &zfcp_sysfs_adapter_attrs))
 		goto failed;
 
+	if (zfcp_diag_sysfs_setup(adapter))
+		goto failed;
+
 	/* report size limit per scatter-gather segment */
 	adapter->ccw_device->dev.dma_parms = &adapter->dma_parms;
 
@@ -426,6 +434,7 @@ void zfcp_adapter_unregister(struct zfcp_adapter *adapter)
 
 	zfcp_fc_wka_ports_force_offline(adapter->gs);
 	zfcp_scsi_adapter_unregister(adapter);
+	zfcp_diag_sysfs_destroy(adapter);
 	sysfs_remove_group(&cdev->dev.kobj, &zfcp_sysfs_adapter_attrs);
 
 	zfcp_erp_thread_kill(adapter);
@@ -449,6 +458,7 @@ void zfcp_adapter_release(struct kref *ref)
 	dev_set_drvdata(&adapter->ccw_device->dev, NULL);
 	zfcp_fc_gs_destroy(adapter);
 	zfcp_free_low_mem_buffers(adapter);
+	zfcp_diag_adapter_free(adapter);
 	kfree(adapter->req_list);
 	kfree(adapter->fc_stats);
 	kfree(adapter->stats_reset_data);
diff --git a/drivers/s390/scsi/zfcp_dbf.c b/drivers/s390/scsi/zfcp_dbf.c
index dccdb41bed8c..1234294700c4 100644
--- a/drivers/s390/scsi/zfcp_dbf.c
+++ b/drivers/s390/scsi/zfcp_dbf.c
@@ -95,11 +95,9 @@ void zfcp_dbf_hba_fsf_res(char *tag, int level, struct zfcp_fsf_req *req)
 	memcpy(rec->u.res.fsf_status_qual, &q_head->fsf_status_qual,
 	       FSF_STATUS_QUALIFIER_SIZE);
 
-	if (q_head->fsf_command != FSF_QTCB_FCP_CMND) {
-		rec->pl_len = q_head->log_length;
-		zfcp_dbf_pl_write(dbf, (char *)q_pref + q_head->log_start,
-				  rec->pl_len, "fsf_res", req->req_id);
-	}
+	rec->pl_len = q_head->log_length;
+	zfcp_dbf_pl_write(dbf, (char *)q_pref + q_head->log_start,
+			  rec->pl_len, "fsf_res", req->req_id);
 
 	debug_event(dbf->hba, level, rec, sizeof(*rec));
 	spin_unlock_irqrestore(&dbf->hba_lock, flags);
diff --git a/drivers/s390/scsi/zfcp_def.h b/drivers/s390/scsi/zfcp_def.h
index 87d2f47a6990..8cc0eefe4ccc 100644
--- a/drivers/s390/scsi/zfcp_def.h
+++ b/drivers/s390/scsi/zfcp_def.h
@@ -4,7 +4,7 @@
  *
  * Global definitions for the zfcp device driver.
  *
- * Copyright IBM Corp. 2002, 2017
+ * Copyright IBM Corp. 2002, 2018
  */
 
 #ifndef ZFCP_DEF_H
@@ -86,6 +86,7 @@
 #define ZFCP_STATUS_FSFREQ_ABORTNOTNEEDED       0x00000080
 #define ZFCP_STATUS_FSFREQ_TMFUNCFAILED         0x00000200
 #define ZFCP_STATUS_FSFREQ_DISMISSED            0x00001000
+#define ZFCP_STATUS_FSFREQ_XDATAINCOMPLETE	0x00020000
 
 /************************* STRUCTURE DEFINITIONS *****************************/
 
@@ -197,6 +198,7 @@ struct zfcp_adapter {
 	struct device_dma_parameters dma_parms;
 	struct zfcp_fc_events events;
 	unsigned long		next_port_scan;
+	struct zfcp_diag_adapter	*diagnostics;
 };
 
 struct zfcp_port {
diff --git a/drivers/s390/scsi/zfcp_diag.c b/drivers/s390/scsi/zfcp_diag.c
new file mode 100644
index 000000000000..67a8f4e57db1
--- /dev/null
+++ b/drivers/s390/scsi/zfcp_diag.c
@@ -0,0 +1,305 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * zfcp device driver
+ *
+ * Functions to handle diagnostics.
+ *
+ * Copyright IBM Corp. 2018
+ */
+
+#include <linux/spinlock.h>
+#include <linux/jiffies.h>
+#include <linux/string.h>
+#include <linux/kernfs.h>
+#include <linux/sysfs.h>
+#include <linux/errno.h>
+#include <linux/slab.h>
+
+#include "zfcp_diag.h"
+#include "zfcp_ext.h"
+#include "zfcp_def.h"
+
+static DECLARE_WAIT_QUEUE_HEAD(__zfcp_diag_publish_wait);
+
+/**
+ * zfcp_diag_adapter_setup() - Setup storage for adapter diagnostics.
+ * @adapter: the adapter to setup diagnostics for.
+ *
+ * Creates the data-structures to store the diagnostics for an adapter. This
+ * overwrites whatever was stored before at &zfcp_adapter->diagnostics!
+ *
+ * Return:
+ * * 0	     - Everyting is OK
+ * * -ENOMEM - Could not allocate all/parts of the data-structures;
+ *	       &zfcp_adapter->diagnostics remains unchanged
+ */
+int zfcp_diag_adapter_setup(struct zfcp_adapter *const adapter)
+{
+	struct zfcp_diag_adapter *diag;
+	struct zfcp_diag_header *hdr;
+
+	diag = kzalloc(sizeof(*diag), GFP_KERNEL);
+	if (diag == NULL)
+		return -ENOMEM;
+
+	diag->max_age = (5 * 1000); /* default value: 5 s */
+
+	/* setup header for port_data */
+	hdr = &diag->port_data.header;
+
+	spin_lock_init(&hdr->access_lock);
+	hdr->buffer = &diag->port_data.data;
+	hdr->buffer_size = sizeof(diag->port_data.data);
+	/* set the timestamp so that the first test on age will always fail */
+	hdr->timestamp = jiffies - msecs_to_jiffies(diag->max_age);
+
+	/* setup header for config_data */
+	hdr = &diag->config_data.header;
+
+	spin_lock_init(&hdr->access_lock);
+	hdr->buffer = &diag->config_data.data;
+	hdr->buffer_size = sizeof(diag->config_data.data);
+	/* set the timestamp so that the first test on age will always fail */
+	hdr->timestamp = jiffies - msecs_to_jiffies(diag->max_age);
+
+	adapter->diagnostics = diag;
+	return 0;
+}
+
+/**
+ * zfcp_diag_adapter_free() - Frees all adapter diagnostics allocations.
+ * @adapter: the adapter whose diagnostic structures should be freed.
+ *
+ * Frees all data-structures in the given adapter that store diagnostics
+ * information. Can savely be called with partially setup diagnostics.
+ */
+void zfcp_diag_adapter_free(struct zfcp_adapter *const adapter)
+{
+	kfree(adapter->diagnostics);
+	adapter->diagnostics = NULL;
+}
+
+/**
+ * zfcp_diag_sysfs_setup() - Setup the sysfs-group for adapter-diagnostics.
+ * @adapter: target adapter to which the group should be added.
+ *
+ * Return: 0 on success; Something else otherwise (see sysfs_create_group()).
+ */
+int zfcp_diag_sysfs_setup(struct zfcp_adapter *const adapter)
+{
+	int rc = sysfs_create_group(&adapter->ccw_device->dev.kobj,
+				    &zfcp_sysfs_diag_attr_group);
+	if (rc == 0)
+		adapter->diagnostics->sysfs_established = 1;
+
+	return rc;
+}
+
+/**
+ * zfcp_diag_sysfs_destroy() - Remove the sysfs-group for adapter-diagnostics.
+ * @adapter: target adapter from which the group should be removed.
+ */
+void zfcp_diag_sysfs_destroy(struct zfcp_adapter *const adapter)
+{
+	if (adapter->diagnostics == NULL ||
+	    !adapter->diagnostics->sysfs_established)
+		return;
+
+	/*
+	 * We need this state-handling so we can prevent warnings being printed
+	 * on the kernel-console in case we have to abort a halfway done
+	 * zfcp_adapter_enqueue(), in which the sysfs-group was not yet
+	 * established. sysfs_remove_group() does this checking as well, but
+	 * still prints a warning in case we try to remove a group that has not
+	 * been established before
+	 */
+	adapter->diagnostics->sysfs_established = 0;
+	sysfs_remove_group(&adapter->ccw_device->dev.kobj,
+			   &zfcp_sysfs_diag_attr_group);
+}
+
+
+/**
+ * zfcp_diag_update_xdata() - Update a diagnostics buffer.
+ * @hdr: the meta data to update.
+ * @data: data to use for the update.
+ * @incomplete: flag stating whether the data in @data is incomplete.
+ */
+void zfcp_diag_update_xdata(struct zfcp_diag_header *const hdr,
+			    const void *const data, const bool incomplete)
+{
+	const unsigned long capture_timestamp = jiffies;
+	unsigned long flags;
+
+	spin_lock_irqsave(&hdr->access_lock, flags);
+
+	/* make sure we never go into the past with an update */
+	if (!time_after_eq(capture_timestamp, hdr->timestamp))
+		goto out;
+
+	hdr->timestamp = capture_timestamp;
+	hdr->incomplete = incomplete;
+	memcpy(hdr->buffer, data, hdr->buffer_size);
+out:
+	spin_unlock_irqrestore(&hdr->access_lock, flags);
+}
+
+/**
+ * zfcp_diag_update_port_data_buffer() - Implementation of
+ *					 &typedef zfcp_diag_update_buffer_func
+ *					 to collect and update Port Data.
+ * @adapter: Adapter to collect Port Data from.
+ *
+ * This call is SYNCHRONOUS ! It blocks till the respective command has
+ * finished completely, or has failed in some way.
+ *
+ * Return:
+ * * 0		- Successfully retrieved new Diagnostics and Updated the buffer;
+ *		  this also includes cases where data was retrieved, but
+ *		  incomplete; you'll have to check the flag ``incomplete``
+ *		  of &struct zfcp_diag_header.
+ * * see zfcp_fsf_exchange_port_data_sync() for possible error-codes (
+ *   excluding -EAGAIN)
+ */
+int zfcp_diag_update_port_data_buffer(struct zfcp_adapter *const adapter)
+{
+	int rc;
+
+	rc = zfcp_fsf_exchange_port_data_sync(adapter->qdio, NULL);
+	if (rc == -EAGAIN)
+		rc = 0; /* signaling incomplete via struct zfcp_diag_header */
+
+	/* buffer-data was updated in zfcp_fsf_exchange_port_data_handler() */
+
+	return rc;
+}
+
+/**
+ * zfcp_diag_update_config_data_buffer() - Implementation of
+ *					   &typedef zfcp_diag_update_buffer_func
+ *					   to collect and update Config Data.
+ * @adapter: Adapter to collect Config Data from.
+ *
+ * This call is SYNCHRONOUS ! It blocks till the respective command has
+ * finished completely, or has failed in some way.
+ *
+ * Return:
+ * * 0		- Successfully retrieved new Diagnostics and Updated the buffer;
+ *		  this also includes cases where data was retrieved, but
+ *		  incomplete; you'll have to check the flag ``incomplete``
+ *		  of &struct zfcp_diag_header.
+ * * see zfcp_fsf_exchange_config_data_sync() for possible error-codes (
+ *   excluding -EAGAIN)
+ */
+int zfcp_diag_update_config_data_buffer(struct zfcp_adapter *const adapter)
+{
+	int rc;
+
+	rc = zfcp_fsf_exchange_config_data_sync(adapter->qdio, NULL);
+	if (rc == -EAGAIN)
+		rc = 0; /* signaling incomplete via struct zfcp_diag_header */
+
+	/* buffer-data was updated in zfcp_fsf_exchange_config_data_handler() */
+
+	return rc;
+}
+
+static int __zfcp_diag_update_buffer(struct zfcp_adapter *const adapter,
+				     struct zfcp_diag_header *const hdr,
+				     zfcp_diag_update_buffer_func buffer_update,
+				     unsigned long *const flags)
+	__must_hold(hdr->access_lock)
+{
+	int rc;
+
+	if (hdr->updating == 1) {
+		rc = wait_event_interruptible_lock_irq(__zfcp_diag_publish_wait,
+						       hdr->updating == 0,
+						       hdr->access_lock);
+		rc = (rc == 0 ? -EAGAIN : -EINTR);
+	} else {
+		hdr->updating = 1;
+		spin_unlock_irqrestore(&hdr->access_lock, *flags);
+
+		/* unlocked, because update function sleeps */
+		rc = buffer_update(adapter);
+
+		spin_lock_irqsave(&hdr->access_lock, *flags);
+		hdr->updating = 0;
+
+		/*
+		 * every thread waiting here went via an interruptible wait,
+		 * so its fine to only wake those
+		 */
+		wake_up_interruptible_all(&__zfcp_diag_publish_wait);
+	}
+
+	return rc;
+}
+
+static bool
+__zfcp_diag_test_buffer_age_isfresh(const struct zfcp_diag_adapter *const diag,
+				    const struct zfcp_diag_header *const hdr)
+	__must_hold(hdr->access_lock)
+{
+	const unsigned long now = jiffies;
+
+	/*
+	 * Should not happen (data is from the future).. if it does, still
+	 * signal that it needs refresh
+	 */
+	if (!time_after_eq(now, hdr->timestamp))
+		return false;
+
+	if (jiffies_to_msecs(now - hdr->timestamp) >= diag->max_age)
+		return false;
+
+	return true;
+}
+
+/**
+ * zfcp_diag_update_buffer_limited() - Collect diagnostics and update a
+ *				       diagnostics buffer rate limited.
+ * @adapter: Adapter to collect the diagnostics from.
+ * @hdr: buffer-header for which to update with the collected diagnostics.
+ * @buffer_update: Specific implementation for collecting and updating.
+ *
+ * This function will cause an update of the given @hdr by calling the also
+ * given @buffer_update function. If called by multiple sources at the same
+ * time, it will synchornize the update by only allowing one source to call
+ * @buffer_update and the others to wait for that source to complete instead
+ * (the wait is interruptible).
+ *
+ * Additionally this version is rate-limited and will only exit if either the
+ * buffer is fresh enough (within the limit) - it will do nothing if the buffer
+ * is fresh enough to begin with -, or if the source/thread that started this
+ * update is the one that made the update (to prevent endless loops).
+ *
+ * Return:
+ * * 0		- If the update was successfully published and/or the buffer is
+ *		  fresh enough
+ * * -EINTR	- If the thread went into the wait-state and was interrupted
+ * * whatever @buffer_update returns
+ */
+int zfcp_diag_update_buffer_limited(struct zfcp_adapter *const adapter,
+				    struct zfcp_diag_header *const hdr,
+				    zfcp_diag_update_buffer_func buffer_update)
+{
+	unsigned long flags;
+	int rc;
+
+	spin_lock_irqsave(&hdr->access_lock, flags);
+
+	for (rc = 0;
+	     !__zfcp_diag_test_buffer_age_isfresh(adapter->diagnostics, hdr);
+	     rc = 0) {
+		rc = __zfcp_diag_update_buffer(adapter, hdr, buffer_update,
+					       &flags);
+		if (rc != -EAGAIN)
+			break;
+	}
+
+	spin_unlock_irqrestore(&hdr->access_lock, flags);
+
+	return rc;
+}
diff --git a/drivers/s390/scsi/zfcp_diag.h b/drivers/s390/scsi/zfcp_diag.h
new file mode 100644
index 000000000000..b9c93d15f67c
--- /dev/null
+++ b/drivers/s390/scsi/zfcp_diag.h
@@ -0,0 +1,101 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * zfcp device driver
+ *
+ * Definitions for handling diagnostics in the the zfcp device driver.
+ *
+ * Copyright IBM Corp. 2018
+ */
+
+#ifndef ZFCP_DIAG_H
+#define ZFCP_DIAG_H
+
+#include <linux/spinlock.h>
+
+#include "zfcp_fsf.h"
+#include "zfcp_def.h"
+
+/**
+ * struct zfcp_diag_header - general part of a diagnostic buffer.
+ * @access_lock: lock protecting all the data in this buffer.
+ * @updating: flag showing that an update for this buffer is currently running.
+ * @incomplete: flag showing that the data in @buffer is incomplete.
+ * @timestamp: time in jiffies when the data of this buffer was last captured.
+ * @buffer: implementation-depending data of this buffer
+ * @buffer_size: size of @buffer
+ */
+struct zfcp_diag_header {
+	spinlock_t	access_lock;
+
+	/* Flags */
+	u64		updating	:1;
+	u64		incomplete	:1;
+
+	unsigned long	timestamp;
+
+	void		*buffer;
+	size_t		buffer_size;
+};
+
+/**
+ * struct zfcp_diag_adapter - central storage for all diagnostics concerning an
+ *			      adapter.
+ * @sysfs_established: flag showing that the associated sysfs-group was created
+ *		       during run of zfcp_adapter_enqueue().
+ * @max_age: maximum age of data in diagnostic buffers before they need to be
+ *	     refreshed (in ms).
+ * @port_data: data retrieved using exchange port data.
+ * @port_data.header: header with metadata for the cache in @port_data.data.
+ * @port_data.data: cached QTCB Bottom of command exchange port data.
+ * @config_data: data retrieved using exchange config data.
+ * @config_data.header: header with metadata for the cache in @config_data.data.
+ * @config_data.data: cached QTCB Bottom of command exchange config data.
+ */
+struct zfcp_diag_adapter {
+	u64	sysfs_established	:1;
+
+	unsigned long	max_age;
+
+	struct {
+		struct zfcp_diag_header		header;
+		struct fsf_qtcb_bottom_port	data;
+	} port_data;
+	struct {
+		struct zfcp_diag_header		header;
+		struct fsf_qtcb_bottom_config	data;
+	} config_data;
+};
+
+int zfcp_diag_adapter_setup(struct zfcp_adapter *const adapter);
+void zfcp_diag_adapter_free(struct zfcp_adapter *const adapter);
+
+int zfcp_diag_sysfs_setup(struct zfcp_adapter *const adapter);
+void zfcp_diag_sysfs_destroy(struct zfcp_adapter *const adapter);
+
+void zfcp_diag_update_xdata(struct zfcp_diag_header *const hdr,
+			    const void *const data, const bool incomplete);
+
+/*
+ * Function-Type used in zfcp_diag_update_buffer_limited() for the function
+ * that does the buffer-implementation dependent work.
+ */
+typedef int (*zfcp_diag_update_buffer_func)(struct zfcp_adapter *const adapter);
+
+int zfcp_diag_update_config_data_buffer(struct zfcp_adapter *const adapter);
+int zfcp_diag_update_port_data_buffer(struct zfcp_adapter *const adapter);
+int zfcp_diag_update_buffer_limited(struct zfcp_adapter *const adapter,
+				    struct zfcp_diag_header *const hdr,
+				    zfcp_diag_update_buffer_func buffer_update);
+
+/**
+ * zfcp_diag_support_sfp() - Return %true if the @adapter supports reporting
+ *			     SFP Data.
+ * @adapter: adapter to test the availability of SFP Data reporting for.
+ */
+static inline bool
+zfcp_diag_support_sfp(const struct zfcp_adapter *const adapter)
+{
+	return !!(adapter->adapter_features & FSF_FEATURE_REPORT_SFP_DATA);
+}
+
+#endif /* ZFCP_DIAG_H */
diff --git a/drivers/s390/scsi/zfcp_erp.c b/drivers/s390/scsi/zfcp_erp.c
index 96f0d34e9459..93655b85b73f 100644
--- a/drivers/s390/scsi/zfcp_erp.c
+++ b/drivers/s390/scsi/zfcp_erp.c
@@ -174,7 +174,7 @@ static enum zfcp_erp_act_type zfcp_erp_required_act(enum zfcp_erp_act_type want,
 			return 0;
 		p_status = atomic_read(&port->status);
 		if (!(p_status & ZFCP_STATUS_COMMON_RUNNING) ||
-		      p_status & ZFCP_STATUS_COMMON_ERP_FAILED)
+		    p_status & ZFCP_STATUS_COMMON_ERP_FAILED)
 			return 0;
 		if (!(p_status & ZFCP_STATUS_COMMON_UNBLOCKED))
 			need = ZFCP_ERP_ACTION_REOPEN_PORT;
@@ -190,7 +190,7 @@ static enum zfcp_erp_act_type zfcp_erp_required_act(enum zfcp_erp_act_type want,
 			return 0;
 		a_status = atomic_read(&adapter->status);
 		if (!(a_status & ZFCP_STATUS_COMMON_RUNNING) ||
-		      a_status & ZFCP_STATUS_COMMON_ERP_FAILED)
+		    a_status & ZFCP_STATUS_COMMON_ERP_FAILED)
 			return 0;
 		if (p_status & ZFCP_STATUS_COMMON_NOESC)
 			return need;
diff --git a/drivers/s390/scsi/zfcp_ext.h b/drivers/s390/scsi/zfcp_ext.h
index 31e8a7240fd7..c8556787cfdc 100644
--- a/drivers/s390/scsi/zfcp_ext.h
+++ b/drivers/s390/scsi/zfcp_ext.h
@@ -167,6 +167,7 @@ extern const struct attribute_group *zfcp_port_attr_groups[];
 extern struct mutex zfcp_sysfs_port_units_mutex;
 extern struct device_attribute *zfcp_sysfs_sdev_attrs[];
 extern struct device_attribute *zfcp_sysfs_shost_attrs[];
+extern const struct attribute_group zfcp_sysfs_diag_attr_group;
 bool zfcp_sysfs_port_is_removing(const struct zfcp_port *const port);
 
 /* zfcp_unit.c */
diff --git a/drivers/s390/scsi/zfcp_fsf.c b/drivers/s390/scsi/zfcp_fsf.c
index cf63916814cc..223a805f0b0b 100644
--- a/drivers/s390/scsi/zfcp_fsf.c
+++ b/drivers/s390/scsi/zfcp_fsf.c
@@ -11,6 +11,7 @@
 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
 
 #include <linux/blktrace_api.h>
+#include <linux/jiffies.h>
 #include <linux/types.h>
 #include <linux/slab.h>
 #include <scsi/fc/fc_els.h>
@@ -19,6 +20,7 @@
 #include "zfcp_dbf.h"
 #include "zfcp_qdio.h"
 #include "zfcp_reqlist.h"
+#include "zfcp_diag.h"
 
 /* timeout for FSF requests sent during scsi_eh: abort or FCP TMF */
 #define ZFCP_FSF_SCSI_ER_TIMEOUT (10*HZ)
@@ -554,6 +556,8 @@ static int zfcp_fsf_exchange_config_evaluate(struct zfcp_fsf_req *req)
 static void zfcp_fsf_exchange_config_data_handler(struct zfcp_fsf_req *req)
 {
 	struct zfcp_adapter *adapter = req->adapter;
+	struct zfcp_diag_header *const diag_hdr =
+		&adapter->diagnostics->config_data.header;
 	struct fsf_qtcb *qtcb = req->qtcb;
 	struct fsf_qtcb_bottom_config *bottom = &qtcb->bottom.config;
 	struct Scsi_Host *shost = adapter->scsi_host;
@@ -570,6 +574,12 @@ static void zfcp_fsf_exchange_config_data_handler(struct zfcp_fsf_req *req)
 
 	switch (qtcb->header.fsf_status) {
 	case FSF_GOOD:
+		/*
+		 * usually we wait with an update till the cache is too old,
+		 * but because we have the data available, update it anyway
+		 */
+		zfcp_diag_update_xdata(diag_hdr, bottom, false);
+
 		if (zfcp_fsf_exchange_config_evaluate(req))
 			return;
 
@@ -585,6 +595,9 @@ static void zfcp_fsf_exchange_config_data_handler(struct zfcp_fsf_req *req)
 				&adapter->status);
 		break;
 	case FSF_EXCHANGE_CONFIG_DATA_INCOMPLETE:
+		zfcp_diag_update_xdata(diag_hdr, bottom, true);
+		req->status |= ZFCP_STATUS_FSFREQ_XDATAINCOMPLETE;
+
 		fc_host_node_name(shost) = 0;
 		fc_host_port_name(shost) = 0;
 		fc_host_port_id(shost) = 0;
@@ -653,16 +666,28 @@ static void zfcp_fsf_exchange_port_evaluate(struct zfcp_fsf_req *req)
 
 static void zfcp_fsf_exchange_port_data_handler(struct zfcp_fsf_req *req)
 {
+	struct zfcp_diag_header *const diag_hdr =
+		&req->adapter->diagnostics->port_data.header;
 	struct fsf_qtcb *qtcb = req->qtcb;
+	struct fsf_qtcb_bottom_port *bottom = &qtcb->bottom.port;
 
 	if (req->status & ZFCP_STATUS_FSFREQ_ERROR)
 		return;
 
 	switch (qtcb->header.fsf_status) {
 	case FSF_GOOD:
+		/*
+		 * usually we wait with an update till the cache is too old,
+		 * but because we have the data available, update it anyway
+		 */
+		zfcp_diag_update_xdata(diag_hdr, bottom, false);
+
 		zfcp_fsf_exchange_port_evaluate(req);
 		break;
 	case FSF_EXCHANGE_CONFIG_DATA_INCOMPLETE:
+		zfcp_diag_update_xdata(diag_hdr, bottom, true);
+		req->status |= ZFCP_STATUS_FSFREQ_XDATAINCOMPLETE;
+
 		zfcp_fsf_exchange_port_evaluate(req);
 		zfcp_fsf_link_down_info_eval(req,
 			&qtcb->header.fsf_status_qual.link_down_info);
@@ -1261,7 +1286,8 @@ int zfcp_fsf_exchange_config_data(struct zfcp_erp_action *erp_action)
 
 	req->qtcb->bottom.config.feature_selection =
 			FSF_FEATURE_NOTIFICATION_LOST |
-			FSF_FEATURE_UPDATE_ALERT;
+			FSF_FEATURE_UPDATE_ALERT |
+			FSF_FEATURE_REQUEST_SFP_DATA;
 	req->erp_action = erp_action;
 	req->handler = zfcp_fsf_exchange_config_data_handler;
 	erp_action->fsf_req_id = req->req_id;
@@ -1278,6 +1304,19 @@ out:
 	return retval;
 }
 
+
+/**
+ * zfcp_fsf_exchange_config_data_sync() - Request information about FCP channel.
+ * @qdio: pointer to the QDIO-Queue to use for sending the command.
+ * @data: pointer to the QTCB-Bottom for storing the result of the command,
+ *	  might be %NULL.
+ *
+ * Returns:
+ * * 0		- Exchange Config Data was successful, @data is complete
+ * * -EIO	- Exchange Config Data was not successful, @data is invalid
+ * * -EAGAIN	- @data contains incomplete data
+ * * -ENOMEM	- Some memory allocation failed along the way
+ */
 int zfcp_fsf_exchange_config_data_sync(struct zfcp_qdio *qdio,
 				       struct fsf_qtcb_bottom_config *data)
 {
@@ -1301,7 +1340,8 @@ int zfcp_fsf_exchange_config_data_sync(struct zfcp_qdio *qdio,
 
 	req->qtcb->bottom.config.feature_selection =
 			FSF_FEATURE_NOTIFICATION_LOST |
-			FSF_FEATURE_UPDATE_ALERT;
+			FSF_FEATURE_UPDATE_ALERT |
+			FSF_FEATURE_REQUEST_SFP_DATA;
 
 	if (data)
 		req->data = data;
@@ -1309,9 +1349,16 @@ int zfcp_fsf_exchange_config_data_sync(struct zfcp_qdio *qdio,
 	zfcp_fsf_start_timer(req, ZFCP_FSF_REQUEST_TIMEOUT);
 	retval = zfcp_fsf_req_send(req);
 	spin_unlock_irq(&qdio->req_q_lock);
+
 	if (!retval) {
 		/* NOTE: ONLY TOUCH SYNC req AGAIN ON req->completion. */
 		wait_for_completion(&req->completion);
+
+		if (req->status &
+		    (ZFCP_STATUS_FSFREQ_ERROR | ZFCP_STATUS_FSFREQ_DISMISSED))
+			retval = -EIO;
+		else if (req->status & ZFCP_STATUS_FSFREQ_XDATAINCOMPLETE)
+			retval = -EAGAIN;
 	}
 
 	zfcp_fsf_req_free(req);
@@ -1369,10 +1416,17 @@ out:
 }
 
 /**
- * zfcp_fsf_exchange_port_data_sync - request information about local port
- * @qdio: pointer to struct zfcp_qdio
- * @data: pointer to struct fsf_qtcb_bottom_port
- * Returns: 0 on success, error otherwise
+ * zfcp_fsf_exchange_port_data_sync() - Request information about local port.
+ * @qdio: pointer to the QDIO-Queue to use for sending the command.
+ * @data: pointer to the QTCB-Bottom for storing the result of the command,
+ *	  might be %NULL.
+ *
+ * Returns:
+ * * 0		- Exchange Port Data was successful, @data is complete
+ * * -EIO	- Exchange Port Data was not successful, @data is invalid
+ * * -EAGAIN	- @data contains incomplete data
+ * * -ENOMEM	- Some memory allocation failed along the way
+ * * -EOPNOTSUPP	- This operation is not supported
  */
 int zfcp_fsf_exchange_port_data_sync(struct zfcp_qdio *qdio,
 				     struct fsf_qtcb_bottom_port *data)
@@ -1408,10 +1462,15 @@ int zfcp_fsf_exchange_port_data_sync(struct zfcp_qdio *qdio,
 	if (!retval) {
 		/* NOTE: ONLY TOUCH SYNC req AGAIN ON req->completion. */
 		wait_for_completion(&req->completion);
+
+		if (req->status &
+		    (ZFCP_STATUS_FSFREQ_ERROR | ZFCP_STATUS_FSFREQ_DISMISSED))
+			retval = -EIO;
+		else if (req->status & ZFCP_STATUS_FSFREQ_XDATAINCOMPLETE)
+			retval = -EAGAIN;
 	}
 
 	zfcp_fsf_req_free(req);
-
 	return retval;
 
 out_unlock:
diff --git a/drivers/s390/scsi/zfcp_fsf.h b/drivers/s390/scsi/zfcp_fsf.h
index 2c658b66318c..2b1e4da1944f 100644
--- a/drivers/s390/scsi/zfcp_fsf.h
+++ b/drivers/s390/scsi/zfcp_fsf.h
@@ -163,6 +163,8 @@
 #define FSF_FEATURE_ELS_CT_CHAINED_SBALS	0x00000020
 #define FSF_FEATURE_UPDATE_ALERT		0x00000100
 #define FSF_FEATURE_MEASUREMENT_DATA		0x00000200
+#define FSF_FEATURE_REQUEST_SFP_DATA		0x00000200
+#define FSF_FEATURE_REPORT_SFP_DATA		0x00000800
 #define FSF_FEATURE_DIF_PROT_TYPE1		0x00010000
 #define FSF_FEATURE_DIX_PROT_TCPIP		0x00020000
 
@@ -407,7 +409,24 @@ struct fsf_qtcb_bottom_port {
 	u8 cp_util;
 	u8 cb_util;
 	u8 a_util;
-	u8 res2[253];
+	u8 res2;
+	u16 temperature;
+	u16 vcc;
+	u16 tx_bias;
+	u16 tx_power;
+	u16 rx_power;
+	union {
+		u16 raw;
+		struct {
+			u16 fec_active		:1;
+			u16:7;
+			u16 connector_type	:2;
+			u16 sfp_invalid		:1;
+			u16 optical_port	:1;
+			u16 port_tx_type	:4;
+		};
+	} sfp_flags;
+	u8 res3[240];
 } __attribute__ ((packed));
 
 union fsf_qtcb_bottom {
diff --git a/drivers/s390/scsi/zfcp_scsi.c b/drivers/s390/scsi/zfcp_scsi.c
index e9ded2befa0d..3910d529c15a 100644
--- a/drivers/s390/scsi/zfcp_scsi.c
+++ b/drivers/s390/scsi/zfcp_scsi.c
@@ -605,7 +605,7 @@ zfcp_scsi_get_fc_host_stats(struct Scsi_Host *host)
 		return NULL;
 
 	ret = zfcp_fsf_exchange_port_data_sync(adapter->qdio, data);
-	if (ret) {
+	if (ret != 0 && ret != -EAGAIN) {
 		kfree(data);
 		return NULL;
 	}
@@ -634,7 +634,7 @@ static void zfcp_scsi_reset_fc_host_stats(struct Scsi_Host *shost)
 		return;
 
 	ret = zfcp_fsf_exchange_port_data_sync(adapter->qdio, data);
-	if (ret)
+	if (ret != 0 && ret != -EAGAIN)
 		kfree(data);
 	else {
 		adapter->stats_reset = jiffies/HZ;
diff --git a/drivers/s390/scsi/zfcp_sysfs.c b/drivers/s390/scsi/zfcp_sysfs.c
index af197e2b3e69..494b9fe9cc94 100644
--- a/drivers/s390/scsi/zfcp_sysfs.c
+++ b/drivers/s390/scsi/zfcp_sysfs.c
@@ -11,6 +11,7 @@
 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
 
 #include <linux/slab.h>
+#include "zfcp_diag.h"
 #include "zfcp_ext.h"
 
 #define ZFCP_DEV_ATTR(_feat, _name, _mode, _show, _store) \
@@ -325,6 +326,50 @@ static ssize_t zfcp_sysfs_port_remove_store(struct device *dev,
 static ZFCP_DEV_ATTR(adapter, port_remove, S_IWUSR, NULL,
 		     zfcp_sysfs_port_remove_store);
 
+static ssize_t
+zfcp_sysfs_adapter_diag_max_age_show(struct device *dev,
+				     struct device_attribute *attr, char *buf)
+{
+	struct zfcp_adapter *adapter = zfcp_ccw_adapter_by_cdev(to_ccwdev(dev));
+	ssize_t rc;
+
+	if (!adapter)
+		return -ENODEV;
+
+	/* ceil(log(2^64 - 1) / log(10)) = 20 */
+	rc = scnprintf(buf, 20 + 2, "%lu\n", adapter->diagnostics->max_age);
+
+	zfcp_ccw_adapter_put(adapter);
+	return rc;
+}
+
+static ssize_t
+zfcp_sysfs_adapter_diag_max_age_store(struct device *dev,
+				      struct device_attribute *attr,
+				      const char *buf, size_t count)
+{
+	struct zfcp_adapter *adapter = zfcp_ccw_adapter_by_cdev(to_ccwdev(dev));
+	unsigned long max_age;
+	ssize_t rc;
+
+	if (!adapter)
+		return -ENODEV;
+
+	rc = kstrtoul(buf, 10, &max_age);
+	if (rc != 0)
+		goto out;
+
+	adapter->diagnostics->max_age = max_age;
+
+	rc = count;
+out:
+	zfcp_ccw_adapter_put(adapter);
+	return rc;
+}
+static ZFCP_DEV_ATTR(adapter, diag_max_age, 0644,
+		     zfcp_sysfs_adapter_diag_max_age_show,
+		     zfcp_sysfs_adapter_diag_max_age_store);
+
 static struct attribute *zfcp_adapter_attrs[] = {
 	&dev_attr_adapter_failed.attr,
 	&dev_attr_adapter_in_recovery.attr,
@@ -337,6 +382,7 @@ static struct attribute *zfcp_adapter_attrs[] = {
 	&dev_attr_adapter_lic_version.attr,
 	&dev_attr_adapter_status.attr,
 	&dev_attr_adapter_hardware_version.attr,
+	&dev_attr_adapter_diag_max_age.attr,
 	NULL
 };
 
@@ -577,7 +623,7 @@ static ssize_t zfcp_sysfs_adapter_util_show(struct device *dev,
 		return -ENOMEM;
 
 	retval = zfcp_fsf_exchange_port_data_sync(adapter->qdio, qtcb_port);
-	if (!retval)
+	if (retval == 0 || retval == -EAGAIN)
 		retval = sprintf(buf, "%u %u %u\n", qtcb_port->cp_util,
 				 qtcb_port->cb_util, qtcb_port->a_util);
 	kfree(qtcb_port);
@@ -603,7 +649,7 @@ static int zfcp_sysfs_adapter_ex_config(struct device *dev,
 		return -ENOMEM;
 
 	retval = zfcp_fsf_exchange_config_data_sync(adapter->qdio, qtcb_config);
-	if (!retval)
+	if (retval == 0 || retval == -EAGAIN)
 		*stat_inf = qtcb_config->stat_info;
 
 	kfree(qtcb_config);
@@ -664,3 +710,123 @@ struct device_attribute *zfcp_sysfs_shost_attrs[] = {
 	&dev_attr_queue_full,
 	NULL
 };
+
+static ssize_t zfcp_sysfs_adapter_diag_b2b_credit_show(
+	struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct zfcp_adapter *adapter = zfcp_ccw_adapter_by_cdev(to_ccwdev(dev));
+	struct zfcp_diag_header *diag_hdr;
+	struct fc_els_flogi *nsp;
+	ssize_t rc = -ENOLINK;
+	unsigned long flags;
+	unsigned int status;
+
+	if (!adapter)
+		return -ENODEV;
+
+	status = atomic_read(&adapter->status);
+	if (0 == (status & ZFCP_STATUS_COMMON_OPEN) ||
+	    0 == (status & ZFCP_STATUS_COMMON_UNBLOCKED) ||
+	    0 != (status & ZFCP_STATUS_COMMON_ERP_FAILED))
+		goto out;
+
+	diag_hdr = &adapter->diagnostics->config_data.header;
+
+	rc = zfcp_diag_update_buffer_limited(
+		adapter, diag_hdr, zfcp_diag_update_config_data_buffer);
+	if (rc != 0)
+		goto out;
+
+	spin_lock_irqsave(&diag_hdr->access_lock, flags);
+	/* nport_serv_param doesn't contain the ELS_Command code */
+	nsp = (struct fc_els_flogi *)((unsigned long)
+					      adapter->diagnostics->config_data
+						      .data.nport_serv_param -
+				      sizeof(u32));
+
+	rc = scnprintf(buf, 5 + 2, "%hu\n",
+		       be16_to_cpu(nsp->fl_csp.sp_bb_cred));
+	spin_unlock_irqrestore(&diag_hdr->access_lock, flags);
+
+out:
+	zfcp_ccw_adapter_put(adapter);
+	return rc;
+}
+static ZFCP_DEV_ATTR(adapter_diag, b2b_credit, 0400,
+		     zfcp_sysfs_adapter_diag_b2b_credit_show, NULL);
+
+#define ZFCP_DEFINE_DIAG_SFP_ATTR(_name, _qtcb_member, _prtsize, _prtfmt)      \
+	static ssize_t zfcp_sysfs_adapter_diag_sfp_##_name##_show(	       \
+		struct device *dev, struct device_attribute *attr, char *buf)  \
+	{								       \
+		struct zfcp_adapter *const adapter =			       \
+			zfcp_ccw_adapter_by_cdev(to_ccwdev(dev));	       \
+		struct zfcp_diag_header *diag_hdr;			       \
+		ssize_t rc = -ENOLINK;					       \
+		unsigned long flags;					       \
+		unsigned int status;					       \
+									       \
+		if (!adapter)						       \
+			return -ENODEV;					       \
+									       \
+		status = atomic_read(&adapter->status);			       \
+		if (0 == (status & ZFCP_STATUS_COMMON_OPEN) ||		       \
+		    0 == (status & ZFCP_STATUS_COMMON_UNBLOCKED) ||	       \
+		    0 != (status & ZFCP_STATUS_COMMON_ERP_FAILED))	       \
+			goto out;					       \
+									       \
+		if (!zfcp_diag_support_sfp(adapter)) {			       \
+			rc = -EOPNOTSUPP;				       \
+			goto out;					       \
+		}							       \
+									       \
+		diag_hdr = &adapter->diagnostics->port_data.header;	       \
+									       \
+		rc = zfcp_diag_update_buffer_limited(			       \
+			adapter, diag_hdr, zfcp_diag_update_port_data_buffer); \
+		if (rc != 0)						       \
+			goto out;					       \
+									       \
+		spin_lock_irqsave(&diag_hdr->access_lock, flags);	       \
+		rc = scnprintf(						       \
+			buf, (_prtsize) + 2, _prtfmt "\n",		       \
+			adapter->diagnostics->port_data.data._qtcb_member);    \
+		spin_unlock_irqrestore(&diag_hdr->access_lock, flags);	       \
+									       \
+	out:								       \
+		zfcp_ccw_adapter_put(adapter);				       \
+		return rc;						       \
+	}								       \
+	static ZFCP_DEV_ATTR(adapter_diag_sfp, _name, 0400,		       \
+			     zfcp_sysfs_adapter_diag_sfp_##_name##_show, NULL)
+
+ZFCP_DEFINE_DIAG_SFP_ATTR(temperature, temperature, 5, "%hu");
+ZFCP_DEFINE_DIAG_SFP_ATTR(vcc, vcc, 5, "%hu");
+ZFCP_DEFINE_DIAG_SFP_ATTR(tx_bias, tx_bias, 5, "%hu");
+ZFCP_DEFINE_DIAG_SFP_ATTR(tx_power, tx_power, 5, "%hu");
+ZFCP_DEFINE_DIAG_SFP_ATTR(rx_power, rx_power, 5, "%hu");
+ZFCP_DEFINE_DIAG_SFP_ATTR(port_tx_type, sfp_flags.port_tx_type, 2, "%hu");
+ZFCP_DEFINE_DIAG_SFP_ATTR(optical_port, sfp_flags.optical_port, 1, "%hu");
+ZFCP_DEFINE_DIAG_SFP_ATTR(sfp_invalid, sfp_flags.sfp_invalid, 1, "%hu");
+ZFCP_DEFINE_DIAG_SFP_ATTR(connector_type, sfp_flags.connector_type, 1, "%hu");
+ZFCP_DEFINE_DIAG_SFP_ATTR(fec_active, sfp_flags.fec_active, 1, "%hu");
+
+static struct attribute *zfcp_sysfs_diag_attrs[] = {
+	&dev_attr_adapter_diag_sfp_temperature.attr,
+	&dev_attr_adapter_diag_sfp_vcc.attr,
+	&dev_attr_adapter_diag_sfp_tx_bias.attr,
+	&dev_attr_adapter_diag_sfp_tx_power.attr,
+	&dev_attr_adapter_diag_sfp_rx_power.attr,
+	&dev_attr_adapter_diag_sfp_port_tx_type.attr,
+	&dev_attr_adapter_diag_sfp_optical_port.attr,
+	&dev_attr_adapter_diag_sfp_sfp_invalid.attr,
+	&dev_attr_adapter_diag_sfp_connector_type.attr,
+	&dev_attr_adapter_diag_sfp_fec_active.attr,
+	&dev_attr_adapter_diag_b2b_credit.attr,
+	NULL,
+};
+
+const struct attribute_group zfcp_sysfs_diag_attr_group = {
+	.name = "diagnostics",
+	.attrs = zfcp_sysfs_diag_attrs,
+};