Merge remote-tracking branch 'target-merge/for-next-merge'

3 files changed, 458 insertions, 180 deletions

diff --git a/drivers/scsi/mpt3sas/mpt3sas_base.h b/drivers/scsi/mpt3sas/mpt3sas_base.h
index f0e462b0880d..9a73c8b66b96 100644
--- a/drivers/scsi/mpt3sas/mpt3sas_base.h
+++ b/drivers/scsi/mpt3sas/mpt3sas_base.h
@@ -248,6 +248,7 @@ struct Mpi2ManufacturingPage11_t {
  * @flags: MPT_TARGET_FLAGS_XXX flags
  * @deleted: target flaged for deletion
  * @tm_busy: target is busy with TM request.
+ * @sdev: The sas_device associated with this target
  */
 struct MPT3SAS_TARGET {
 	struct scsi_target *starget;
@@ -257,6 +258,7 @@ struct MPT3SAS_TARGET {
 	u32	flags;
 	u8	deleted;
 	u8	tm_busy;
+	struct	_sas_device *sdev;
 };
 
 
@@ -335,6 +337,9 @@ struct _internal_cmd {
  * @pfa_led_on: flag for PFA LED status
  * @pend_sas_rphy_add: flag to check if device is in sas_rphy_add()
  *	addition routine.
+ * @enclosure_level: used for enclosure services
+ * @connector_name: ASCII value from pg0.ConnectorName
+ * @refcount: reference count for deletion
  */
 struct _sas_device {
 	struct list_head list;
@@ -358,8 +363,24 @@ struct _sas_device {
 	u8	pend_sas_rphy_add;
 	u8	enclosure_level;
 	u8	connector_name[4];
+	struct kref refcount;
 };
 
+static inline void sas_device_get(struct _sas_device *s)
+{
+	kref_get(&s->refcount);
+}
+
+static inline void sas_device_free(struct kref *r)
+{
+	kfree(container_of(r, struct _sas_device, refcount));
+}
+
+static inline void sas_device_put(struct _sas_device *s)
+{
+	kref_put(&s->refcount, sas_device_free);
+}
+
 /**
  * struct _raid_device - raid volume link list
  * @list: sas device list
@@ -1090,7 +1111,9 @@ struct _sas_node *mpt3sas_scsih_expander_find_by_handle(
 	struct MPT3SAS_ADAPTER *ioc, u16 handle);
 struct _sas_node *mpt3sas_scsih_expander_find_by_sas_address(
 	struct MPT3SAS_ADAPTER *ioc, u64 sas_address);
-struct _sas_device *mpt3sas_scsih_sas_device_find_by_sas_address(
+struct _sas_device *mpt3sas_get_sdev_by_addr(
+	 struct MPT3SAS_ADAPTER *ioc, u64 sas_address);
+struct _sas_device *__mpt3sas_get_sdev_by_addr(
 	struct MPT3SAS_ADAPTER *ioc, u64 sas_address);
 
 void mpt3sas_port_enable_complete(struct MPT3SAS_ADAPTER *ioc);
diff --git a/drivers/scsi/mpt3sas/mpt3sas_scsih.c b/drivers/scsi/mpt3sas/mpt3sas_scsih.c
index 8ccef38523fa..9e6843275fdf 100644
--- a/drivers/scsi/mpt3sas/mpt3sas_scsih.c
+++ b/drivers/scsi/mpt3sas/mpt3sas_scsih.c
@@ -175,6 +175,7 @@ struct sense_info {
  * @VP_ID: virtual port id
  * @ignore: flag meaning this event has been marked to ignore
  * @event: firmware event MPI2_EVENT_XXX defined in mpt2_ioc.h
+ * @refcount: reference count for fw_event_work
  * @event_data: reply event data payload follows
  *
  * This object stored on ioc->fw_event_list.
@@ -191,9 +192,37 @@ struct fw_event_work {
 	u8			VP_ID;
 	u8			ignore;
 	u16			event;
+	struct kref		refcount;
 	char			event_data[0] __aligned(4);
 };
 
+static void fw_event_work_free(struct kref *r)
+{
+	kfree(container_of(r, struct fw_event_work, refcount));
+}
+
+static void fw_event_work_get(struct fw_event_work *fw_work)
+{
+	kref_get(&fw_work->refcount);
+}
+
+static void fw_event_work_put(struct fw_event_work *fw_work)
+{
+	kref_put(&fw_work->refcount, fw_event_work_free);
+}
+
+static struct fw_event_work *alloc_fw_event_work(int len)
+{
+	struct fw_event_work *fw_event;
+
+	fw_event = kzalloc(sizeof(*fw_event) + len, GFP_ATOMIC);
+	if (!fw_event)
+		return NULL;
+
+	kref_init(&fw_event->refcount);
+	return fw_event;
+}
+
 /* raid transport support */
 static struct raid_template *mpt3sas_raid_template;
 
@@ -518,8 +547,61 @@ _scsih_determine_boot_device(struct MPT3SAS_ADAPTER *ioc,
 	}
 }
 
+static struct _sas_device *
+__mpt3sas_get_sdev_from_target(struct MPT3SAS_ADAPTER *ioc,
+	struct MPT3SAS_TARGET *tgt_priv)
+{
+	struct _sas_device *ret;
+
+	assert_spin_locked(&ioc->sas_device_lock);
+
+	ret = tgt_priv->sdev;
+	if (ret)
+		sas_device_get(ret);
+
+	return ret;
+}
+
+static struct _sas_device *
+mpt3sas_get_sdev_from_target(struct MPT3SAS_ADAPTER *ioc,
+	struct MPT3SAS_TARGET *tgt_priv)
+{
+	struct _sas_device *ret;
+	unsigned long flags;
+
+	spin_lock_irqsave(&ioc->sas_device_lock, flags);
+	ret = __mpt3sas_get_sdev_from_target(ioc, tgt_priv);
+	spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
+
+	return ret;
+}
+
+struct _sas_device *
+__mpt3sas_get_sdev_by_addr(struct MPT3SAS_ADAPTER *ioc,
+	u64 sas_address)
+{
+	struct _sas_device *sas_device;
+
+	assert_spin_locked(&ioc->sas_device_lock);
+
+	list_for_each_entry(sas_device, &ioc->sas_device_list, list)
+		if (sas_device->sas_address == sas_address)
+			goto found_device;
+
+	list_for_each_entry(sas_device, &ioc->sas_device_init_list, list)
+		if (sas_device->sas_address == sas_address)
+			goto found_device;
+
+	return NULL;
+
+found_device:
+	sas_device_get(sas_device);
+	return sas_device;
+}
+
+
 /**
- * mpt3sas_scsih_sas_device_find_by_sas_address - sas device search
+ * mpt3sas_get_sdev_by_addr - sas device search
  * @ioc: per adapter object
  * @sas_address: sas address
  * Context: Calling function should acquire ioc->sas_device_lock
@@ -528,24 +610,44 @@ _scsih_determine_boot_device(struct MPT3SAS_ADAPTER *ioc,
  * object.
  */
 struct _sas_device *
-mpt3sas_scsih_sas_device_find_by_sas_address(struct MPT3SAS_ADAPTER *ioc,
+mpt3sas_get_sdev_by_addr(struct MPT3SAS_ADAPTER *ioc,
 	u64 sas_address)
 {
 	struct _sas_device *sas_device;
+	unsigned long flags;
+
+	spin_lock_irqsave(&ioc->sas_device_lock, flags);
+	sas_device = __mpt3sas_get_sdev_by_addr(ioc,
+			sas_address);
+	spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
+
+	return sas_device;
+}
+
+static struct _sas_device *
+__mpt3sas_get_sdev_by_handle(struct MPT3SAS_ADAPTER *ioc, u16 handle)
+{
+	struct _sas_device *sas_device;
+
+	assert_spin_locked(&ioc->sas_device_lock);
 
 	list_for_each_entry(sas_device, &ioc->sas_device_list, list)
-		if (sas_device->sas_address == sas_address)
-			return sas_device;
+		if (sas_device->handle == handle)
+			goto found_device;
 
 	list_for_each_entry(sas_device, &ioc->sas_device_init_list, list)
-		if (sas_device->sas_address == sas_address)
-			return sas_device;
+		if (sas_device->handle == handle)
+			goto found_device;
 
 	return NULL;
+
+found_device:
+	sas_device_get(sas_device);
+	return sas_device;
 }
 
 /**
- * _scsih_sas_device_find_by_handle - sas device search
+ * mpt3sas_get_sdev_by_handle - sas device search
  * @ioc: per adapter object
  * @handle: sas device handle (assigned by firmware)
  * Context: Calling function should acquire ioc->sas_device_lock
@@ -554,19 +656,16 @@ mpt3sas_scsih_sas_device_find_by_sas_address(struct MPT3SAS_ADAPTER *ioc,
  * object.
  */
 static struct _sas_device *
-_scsih_sas_device_find_by_handle(struct MPT3SAS_ADAPTER *ioc, u16 handle)
+mpt3sas_get_sdev_by_handle(struct MPT3SAS_ADAPTER *ioc, u16 handle)
 {
 	struct _sas_device *sas_device;
+	unsigned long flags;
 
-	list_for_each_entry(sas_device, &ioc->sas_device_list, list)
-		if (sas_device->handle == handle)
-			return sas_device;
-
-	list_for_each_entry(sas_device, &ioc->sas_device_init_list, list)
-		if (sas_device->handle == handle)
-			return sas_device;
+	spin_lock_irqsave(&ioc->sas_device_lock, flags);
+	sas_device = __mpt3sas_get_sdev_by_handle(ioc, handle);
+	spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
 
-	return NULL;
+	return sas_device;
 }
 
 /**
@@ -575,7 +674,7 @@ _scsih_sas_device_find_by_handle(struct MPT3SAS_ADAPTER *ioc, u16 handle)
  * @sas_device: the sas_device object
  * Context: This function will acquire ioc->sas_device_lock.
  *
- * Removing object and freeing associated memory from the ioc->sas_device_list.
+ * If sas_device is on the list, remove it and decrement its reference count.
  */
 static void
 _scsih_sas_device_remove(struct MPT3SAS_ADAPTER *ioc,
@@ -601,10 +700,15 @@ _scsih_sas_device_remove(struct MPT3SAS_ADAPTER *ioc,
 		   "removing enclosure level(0x%04x), connector name( %s)\n",
 		   ioc->name, sas_device->enclosure_level,
 		   sas_device->connector_name);
-
+	/*
+	 * The lock serializes access to the list, but we still need to verify
+	 * that nobody removed the entry while we were waiting on the lock.
+	 */
 	spin_lock_irqsave(&ioc->sas_device_lock, flags);
-	list_del(&sas_device->list);
-	kfree(sas_device);
+	if (!list_empty(&sas_device->list)) {
+		list_del_init(&sas_device->list);
+		sas_device_put(sas_device);
+	}
 	spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
 }
 
@@ -625,12 +729,17 @@ _scsih_device_remove_by_handle(struct MPT3SAS_ADAPTER *ioc, u16 handle)
 		return;
 
 	spin_lock_irqsave(&ioc->sas_device_lock, flags);
-	sas_device = _scsih_sas_device_find_by_handle(ioc, handle);
-	if (sas_device)
-		list_del(&sas_device->list);
+	sas_device = __mpt3sas_get_sdev_by_handle(ioc, handle);
+	if (sas_device) {
+		list_del_init(&sas_device->list);
+		sas_device_put(sas_device);
+	}
 	spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
-	if (sas_device)
+
+	if (sas_device) {
 		_scsih_remove_device(ioc, sas_device);
+		sas_device_put(sas_device);
+	}
 }
 
 /**
@@ -651,13 +760,17 @@ mpt3sas_device_remove_by_sas_address(struct MPT3SAS_ADAPTER *ioc,
 		return;
 
 	spin_lock_irqsave(&ioc->sas_device_lock, flags);
-	sas_device = mpt3sas_scsih_sas_device_find_by_sas_address(ioc,
-	    sas_address);
-	if (sas_device)
-		list_del(&sas_device->list);
+	sas_device = __mpt3sas_get_sdev_by_addr(ioc, sas_address);
+	if (sas_device) {
+		list_del_init(&sas_device->list);
+		sas_device_put(sas_device);
+	}
 	spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
-	if (sas_device)
+
+	if (sas_device) {
 		_scsih_remove_device(ioc, sas_device);
+		sas_device_put(sas_device);
+	}
 }
 
 /**
@@ -692,6 +805,7 @@ _scsih_sas_device_add(struct MPT3SAS_ADAPTER *ioc,
 		    sas_device->enclosure_level, sas_device->connector_name));
 
 	spin_lock_irqsave(&ioc->sas_device_lock, flags);
+	sas_device_get(sas_device);
 	list_add_tail(&sas_device->list, &ioc->sas_device_list);
 	spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
 
@@ -745,6 +859,7 @@ _scsih_sas_device_init_add(struct MPT3SAS_ADAPTER *ioc,
 		    sas_device->connector_name));
 
 	spin_lock_irqsave(&ioc->sas_device_lock, flags);
+	sas_device_get(sas_device);
 	list_add_tail(&sas_device->list, &ioc->sas_device_init_list);
 	_scsih_determine_boot_device(ioc, sas_device, 0);
 	spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
@@ -1123,12 +1238,15 @@ _scsih_change_queue_depth(struct scsi_device *sdev, int qdepth)
 		goto not_sata;
 	if ((sas_target_priv_data->flags & MPT_TARGET_FLAGS_VOLUME))
 		goto not_sata;
+
 	spin_lock_irqsave(&ioc->sas_device_lock, flags);
-	sas_device = mpt3sas_scsih_sas_device_find_by_sas_address(ioc,
-	   sas_device_priv_data->sas_target->sas_address);
-	if (sas_device && sas_device->device_info &
-	    MPI2_SAS_DEVICE_INFO_SATA_DEVICE)
-		max_depth = MPT3SAS_SATA_QUEUE_DEPTH;
+	sas_device = __mpt3sas_get_sdev_from_target(ioc, sas_target_priv_data);
+	if (sas_device) {
+		if (sas_device->device_info & MPI2_SAS_DEVICE_INFO_SATA_DEVICE)
+			max_depth = MPT3SAS_SATA_QUEUE_DEPTH;
+
+		sas_device_put(sas_device);
+	}
 	spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
 
  not_sata:
@@ -1185,12 +1303,13 @@ _scsih_target_alloc(struct scsi_target *starget)
 	/* sas/sata devices */
 	spin_lock_irqsave(&ioc->sas_device_lock, flags);
 	rphy = dev_to_rphy(starget->dev.parent);
-	sas_device = mpt3sas_scsih_sas_device_find_by_sas_address(ioc,
+	sas_device = __mpt3sas_get_sdev_by_addr(ioc,
 	   rphy->identify.sas_address);
 
 	if (sas_device) {
 		sas_target_priv_data->handle = sas_device->handle;
 		sas_target_priv_data->sas_address = sas_device->sas_address;
+		sas_target_priv_data->sdev = sas_device;
 		sas_device->starget = starget;
 		sas_device->id = starget->id;
 		sas_device->channel = starget->channel;
@@ -1240,13 +1359,21 @@ _scsih_target_destroy(struct scsi_target *starget)
 
 	spin_lock_irqsave(&ioc->sas_device_lock, flags);
 	rphy = dev_to_rphy(starget->dev.parent);
-	sas_device = mpt3sas_scsih_sas_device_find_by_sas_address(ioc,
-	   rphy->identify.sas_address);
+	sas_device = __mpt3sas_get_sdev_from_target(ioc, sas_target_priv_data);
 	if (sas_device && (sas_device->starget == starget) &&
 	    (sas_device->id == starget->id) &&
 	    (sas_device->channel == starget->channel))
 		sas_device->starget = NULL;
 
+	if (sas_device) {
+		/*
+		 * Corresponding get() is in _scsih_target_alloc()
+		 */
+		sas_target_priv_data->sdev = NULL;
+		sas_device_put(sas_device);
+
+		sas_device_put(sas_device);
+	}
 	spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
 
  out:
@@ -1302,7 +1429,7 @@ _scsih_slave_alloc(struct scsi_device *sdev)
 
 	if (!(sas_target_priv_data->flags & MPT_TARGET_FLAGS_VOLUME)) {
 		spin_lock_irqsave(&ioc->sas_device_lock, flags);
-		sas_device = mpt3sas_scsih_sas_device_find_by_sas_address(ioc,
+		sas_device = __mpt3sas_get_sdev_by_addr(ioc,
 					sas_target_priv_data->sas_address);
 		if (sas_device && (sas_device->starget == NULL)) {
 			sdev_printk(KERN_INFO, sdev,
@@ -1310,6 +1437,10 @@ _scsih_slave_alloc(struct scsi_device *sdev)
 				__func__, __LINE__);
 			sas_device->starget = starget;
 		}
+
+		if (sas_device)
+			sas_device_put(sas_device);
+
 		spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
 	}
 
@@ -1344,10 +1475,14 @@ _scsih_slave_destroy(struct scsi_device *sdev)
 
 	if (!(sas_target_priv_data->flags & MPT_TARGET_FLAGS_VOLUME)) {
 		spin_lock_irqsave(&ioc->sas_device_lock, flags);
-		sas_device = mpt3sas_scsih_sas_device_find_by_sas_address(ioc,
-		   sas_target_priv_data->sas_address);
+		sas_device = __mpt3sas_get_sdev_from_target(ioc,
+				sas_target_priv_data);
 		if (sas_device && !sas_target_priv_data->num_luns)
 			sas_device->starget = NULL;
+
+		if (sas_device)
+			sas_device_put(sas_device);
+
 		spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
 	}
 
@@ -1783,7 +1918,7 @@ _scsih_slave_configure(struct scsi_device *sdev)
 	}
 
 	spin_lock_irqsave(&ioc->sas_device_lock, flags);
-	sas_device = mpt3sas_scsih_sas_device_find_by_sas_address(ioc,
+	sas_device = __mpt3sas_get_sdev_by_addr(ioc,
 	   sas_device_priv_data->sas_target->sas_address);
 	if (!sas_device) {
 		spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
@@ -1823,12 +1958,12 @@ _scsih_slave_configure(struct scsi_device *sdev)
 		     ds, sas_device->enclosure_level,
 		     sas_device->connector_name);
 
+	sas_device_put(sas_device);
 	spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
 
 	if (!ssp_target)
 		_scsih_display_sata_capabilities(ioc, handle, sdev);
 
-
 	_scsih_change_queue_depth(sdev, qdepth);
 
 	if (ssp_target) {
@@ -2219,8 +2354,7 @@ _scsih_tm_display_info(struct MPT3SAS_ADAPTER *ioc, struct scsi_cmnd *scmd)
 		    device_str, (unsigned long long)priv_target->sas_address);
 	} else {
 		spin_lock_irqsave(&ioc->sas_device_lock, flags);
-		sas_device = mpt3sas_scsih_sas_device_find_by_sas_address(ioc,
-		    priv_target->sas_address);
+		sas_device = __mpt3sas_get_sdev_from_target(ioc, priv_target);
 		if (sas_device) {
 			if (priv_target->flags &
 			    MPT_TARGET_FLAGS_RAID_COMPONENT) {
@@ -2246,8 +2380,9 @@ _scsih_tm_display_info(struct MPT3SAS_ADAPTER *ioc, struct scsi_cmnd *scmd)
 				"enclosure level(0x%04x),connector name(%s)\n",
 				 sas_device->enclosure_level,
 				 sas_device->connector_name);
+
+			sas_device_put(sas_device);
 		}
-		spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
 	}
 }
 
@@ -2321,10 +2456,11 @@ _scsih_dev_reset(struct scsi_cmnd *scmd)
 {
 	struct MPT3SAS_ADAPTER *ioc = shost_priv(scmd->device->host);
 	struct MPT3SAS_DEVICE *sas_device_priv_data;
-	struct _sas_device *sas_device;
-	unsigned long flags;
+	struct _sas_device *sas_device = NULL;
 	u16	handle;
 	int r;
+	struct scsi_target *starget = scmd->device->sdev_target;
+	struct MPT3SAS_TARGET *target_priv_data = starget->hostdata;
 
 	sdev_printk(KERN_INFO, scmd->device,
 		"attempting device reset! scmd(%p)\n", scmd);
@@ -2344,12 +2480,10 @@ _scsih_dev_reset(struct scsi_cmnd *scmd)
 	handle = 0;
 	if (sas_device_priv_data->sas_target->flags &
 	    MPT_TARGET_FLAGS_RAID_COMPONENT) {
-		spin_lock_irqsave(&ioc->sas_device_lock, flags);
-		sas_device = _scsih_sas_device_find_by_handle(ioc,
-		   sas_device_priv_data->sas_target->handle);
+		sas_device = mpt3sas_get_sdev_from_target(ioc,
+				target_priv_data);
 		if (sas_device)
 			handle = sas_device->volume_handle;
-		spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
 	} else
 		handle = sas_device_priv_data->sas_target->handle;
 
@@ -2366,6 +2500,10 @@ _scsih_dev_reset(struct scsi_cmnd *scmd)
  out:
 	sdev_printk(KERN_INFO, scmd->device, "device reset: %s scmd(%p)\n",
 	    ((r == SUCCESS) ? "SUCCESS" : "FAILED"), scmd);
+
+	if (sas_device)
+		sas_device_put(sas_device);
+
 	return r;
 }
 
@@ -2380,11 +2518,11 @@ _scsih_target_reset(struct scsi_cmnd *scmd)
 {
 	struct MPT3SAS_ADAPTER *ioc = shost_priv(scmd->device->host);
 	struct MPT3SAS_DEVICE *sas_device_priv_data;
-	struct _sas_device *sas_device;
-	unsigned long flags;
+	struct _sas_device *sas_device = NULL;
 	u16	handle;
 	int r;
 	struct scsi_target *starget = scmd->device->sdev_target;
+	struct MPT3SAS_TARGET *target_priv_data = starget->hostdata;
 
 	starget_printk(KERN_INFO, starget, "attempting target reset! scmd(%p)\n",
 		scmd);
@@ -2404,12 +2542,10 @@ _scsih_target_reset(struct scsi_cmnd *scmd)
 	handle = 0;
 	if (sas_device_priv_data->sas_target->flags &
 	    MPT_TARGET_FLAGS_RAID_COMPONENT) {
-		spin_lock_irqsave(&ioc->sas_device_lock, flags);
-		sas_device = _scsih_sas_device_find_by_handle(ioc,
-		   sas_device_priv_data->sas_target->handle);
+		sas_device = mpt3sas_get_sdev_from_target(ioc,
+				target_priv_data);
 		if (sas_device)
 			handle = sas_device->volume_handle;
-		spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
 	} else
 		handle = sas_device_priv_data->sas_target->handle;
 
@@ -2426,6 +2562,10 @@ _scsih_target_reset(struct scsi_cmnd *scmd)
  out:
 	starget_printk(KERN_INFO, starget, "target reset: %s scmd(%p)\n",
 	    ((r == SUCCESS) ? "SUCCESS" : "FAILED"), scmd);
+
+	if (sas_device)
+		sas_device_put(sas_device);
+
 	return r;
 }
 
@@ -2483,32 +2623,36 @@ _scsih_fw_event_add(struct MPT3SAS_ADAPTER *ioc, struct fw_event_work *fw_event)
 		return;
 
 	spin_lock_irqsave(&ioc->fw_event_lock, flags);
+	fw_event_work_get(fw_event);
 	INIT_LIST_HEAD(&fw_event->list);
 	list_add_tail(&fw_event->list, &ioc->fw_event_list);
 	INIT_WORK(&fw_event->work, _firmware_event_work);
+	fw_event_work_get(fw_event);
 	queue_work(ioc->firmware_event_thread, &fw_event->work);
 	spin_unlock_irqrestore(&ioc->fw_event_lock, flags);
 }
 
 /**
- * _scsih_fw_event_free - delete fw_event
+ * _scsih_fw_event_del_from_list - delete fw_event from the list
  * @ioc: per adapter object
  * @fw_event: object describing the event
  * Context: This function will acquire ioc->fw_event_lock.
  *
- * This removes firmware event object from link list, frees associated memory.
+ * If the fw_event is on the fw_event_list, remove it and do a put.
  *
  * Return nothing.
  */
 static void
-_scsih_fw_event_free(struct MPT3SAS_ADAPTER *ioc, struct fw_event_work
+_scsih_fw_event_del_from_list(struct MPT3SAS_ADAPTER *ioc, struct fw_event_work
 	*fw_event)
 {
 	unsigned long flags;
 
 	spin_lock_irqsave(&ioc->fw_event_lock, flags);
-	list_del(&fw_event->list);
-	kfree(fw_event);
+	if (!list_empty(&fw_event->list)) {
+		list_del_init(&fw_event->list);
+		fw_event_work_put(fw_event);
+	}
 	spin_unlock_irqrestore(&ioc->fw_event_lock, flags);
 }
 
@@ -2528,14 +2672,14 @@ mpt3sas_send_trigger_data_event(struct MPT3SAS_ADAPTER *ioc,
 
 	if (ioc->is_driver_loading)
 		return;
-	fw_event = kzalloc(sizeof(*fw_event) + sizeof(*event_data),
-			   GFP_ATOMIC);
+	fw_event = alloc_fw_event_work(sizeof(*event_data));
 	if (!fw_event)
 		return;
 	fw_event->event = MPT3SAS_PROCESS_TRIGGER_DIAG;
 	fw_event->ioc = ioc;
 	memcpy(fw_event->event_data, event_data, sizeof(*event_data));
 	_scsih_fw_event_add(ioc, fw_event);
+	fw_event_work_put(fw_event);
 }
 
 /**
@@ -2551,12 +2695,13 @@ _scsih_error_recovery_delete_devices(struct MPT3SAS_ADAPTER *ioc)
 
 	if (ioc->is_driver_loading)
 		return;
-	fw_event = kzalloc(sizeof(struct fw_event_work), GFP_ATOMIC);
+	fw_event = alloc_fw_event_work(0);
 	if (!fw_event)
 		return;
 	fw_event->event = MPT3SAS_REMOVE_UNRESPONDING_DEVICES;
 	fw_event->ioc = ioc;
 	_scsih_fw_event_add(ioc, fw_event);
+	fw_event_work_put(fw_event);
 }
 
 /**
@@ -2570,12 +2715,29 @@ mpt3sas_port_enable_complete(struct MPT3SAS_ADAPTER *ioc)
 {
 	struct fw_event_work *fw_event;
 
-	fw_event = kzalloc(sizeof(struct fw_event_work), GFP_ATOMIC);
+	fw_event = alloc_fw_event_work(0);
 	if (!fw_event)
 		return;
 	fw_event->event = MPT3SAS_PORT_ENABLE_COMPLETE;
 	fw_event->ioc = ioc;
 	_scsih_fw_event_add(ioc, fw_event);
+	fw_event_work_put(fw_event);
+}
+
+static struct fw_event_work *dequeue_next_fw_event(struct MPT3SAS_ADAPTER *ioc)
+{
+	unsigned long flags;
+	struct fw_event_work *fw_event = NULL;
+
+	spin_lock_irqsave(&ioc->fw_event_lock, flags);
+	if (!list_empty(&ioc->fw_event_list)) {
+		fw_event = list_first_entry(&ioc->fw_event_list,
+				struct fw_event_work, list);
+		list_del_init(&fw_event->list);
+	}
+	spin_unlock_irqrestore(&ioc->fw_event_lock, flags);
+
+	return fw_event;
 }
 
 /**
@@ -2590,17 +2752,25 @@ mpt3sas_port_enable_complete(struct MPT3SAS_ADAPTER *ioc)
 static void
 _scsih_fw_event_cleanup_queue(struct MPT3SAS_ADAPTER *ioc)
 {
-	struct fw_event_work *fw_event, *next;
+	struct fw_event_work *fw_event;
 
 	if (list_empty(&ioc->fw_event_list) ||
 	     !ioc->firmware_event_thread || in_interrupt())
 		return;
 
-	list_for_each_entry_safe(fw_event, next, &ioc->fw_event_list, list) {
-		if (cancel_delayed_work_sync(&fw_event->delayed_work)) {
-			_scsih_fw_event_free(ioc, fw_event);
-			continue;
-		}
+	while ((fw_event = dequeue_next_fw_event(ioc))) {
+		/*
+		 * Wait on the fw_event to complete. If this returns 1, then
+		 * the event was never executed, and we need a put for the
+		 * reference the delayed_work had on the fw_event.
+		 *
+		 * If it did execute, we wait for it to finish, and the put will
+		 * happen from _firmware_event_work()
+		 */
+		if (cancel_work_sync(&fw_event->work))
+			fw_event_work_put(fw_event);
+
+		fw_event_work_put(fw_event);
 	}
 }
 
@@ -2763,7 +2933,7 @@ _scsih_block_io_device(struct MPT3SAS_ADAPTER *ioc, u16 handle)
 	struct scsi_device *sdev;
 	struct _sas_device *sas_device;
 
-	sas_device = _scsih_sas_device_find_by_handle(ioc, handle);
+	sas_device = mpt3sas_get_sdev_by_handle(ioc, handle);
 	if (!sas_device)
 		return;
 
@@ -2779,6 +2949,8 @@ _scsih_block_io_device(struct MPT3SAS_ADAPTER *ioc, u16 handle)
 			continue;
 		_scsih_internal_device_block(sdev, sas_device_priv_data);
 	}
+
+	sas_device_put(sas_device);
 }
 
 /**
@@ -2804,15 +2976,15 @@ _scsih_block_io_to_children_attached_to_ex(struct MPT3SAS_ADAPTER *ioc,
 
 	list_for_each_entry(mpt3sas_port,
 	   &sas_expander->sas_port_list, port_list) {
-		if (mpt3sas_port->remote_identify.device_type ==
-		    SAS_END_DEVICE) {
+		if (mpt3sas_port->remote_identify.device_type == SAS_END_DEVICE) {
 			spin_lock_irqsave(&ioc->sas_device_lock, flags);
-			sas_device =
-			    mpt3sas_scsih_sas_device_find_by_sas_address(ioc,
-			   mpt3sas_port->remote_identify.sas_address);
-			if (sas_device)
+			sas_device = __mpt3sas_get_sdev_by_addr(ioc,
+					mpt3sas_port->remote_identify.sas_address);
+			if (sas_device) {
 				set_bit(sas_device->handle,
-				    ioc->blocking_handles);
+					ioc->blocking_handles);
+				sas_device_put(sas_device);
+			}
 			spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
 		}
 	}
@@ -2880,7 +3052,7 @@ _scsih_tm_tr_send(struct MPT3SAS_ADAPTER *ioc, u16 handle)
 {
 	Mpi2SCSITaskManagementRequest_t *mpi_request;
 	u16 smid;
-	struct _sas_device *sas_device;
+	struct _sas_device *sas_device = NULL;
 	struct MPT3SAS_TARGET *sas_target_priv_data = NULL;
 	u64 sas_address = 0;
 	unsigned long flags;
@@ -2913,7 +3085,7 @@ _scsih_tm_tr_send(struct MPT3SAS_ADAPTER *ioc, u16 handle)
 		return;
 
 	spin_lock_irqsave(&ioc->sas_device_lock, flags);
-	sas_device = _scsih_sas_device_find_by_handle(ioc, handle);
+	sas_device = __mpt3sas_get_sdev_by_handle(ioc, handle);
 	if (sas_device && sas_device->starget &&
 	    sas_device->starget->hostdata) {
 		sas_target_priv_data = sas_device->starget->hostdata;
@@ -2947,14 +3119,14 @@ _scsih_tm_tr_send(struct MPT3SAS_ADAPTER *ioc, u16 handle)
 	if (!smid) {
 		delayed_tr = kzalloc(sizeof(*delayed_tr), GFP_ATOMIC);
 		if (!delayed_tr)
-			return;
+			goto out;
 		INIT_LIST_HEAD(&delayed_tr->list);
 		delayed_tr->handle = handle;
 		list_add_tail(&delayed_tr->list, &ioc->delayed_tr_list);
 		dewtprintk(ioc, pr_info(MPT3SAS_FMT
 		    "DELAYED:tr:handle(0x%04x), (open)\n",
 		    ioc->name, handle));
-		return;
+		goto out;
 	}
 
 	dewtprintk(ioc, pr_info(MPT3SAS_FMT
@@ -2968,6 +3140,9 @@ _scsih_tm_tr_send(struct MPT3SAS_ADAPTER *ioc, u16 handle)
 	mpi_request->TaskType = MPI2_SCSITASKMGMT_TASKTYPE_TARGET_RESET;
 	mpt3sas_base_put_smid_hi_priority(ioc, smid);
 	mpt3sas_trigger_master(ioc, MASTER_TRIGGER_DEVICE_REMOVAL);
+out:
+	if (sas_device)
+		sas_device_put(sas_device);
 }
 
 /**
@@ -3818,7 +3993,6 @@ _scsih_scsi_ioc_info(struct MPT3SAS_ADAPTER *ioc, struct scsi_cmnd *scmd,
 	char *desc_scsi_state = ioc->tmp_string;
 	u32 log_info = le32_to_cpu(mpi_reply->IOCLogInfo);
 	struct _sas_device *sas_device = NULL;
-	unsigned long flags;
 	struct scsi_target *starget = scmd->device->sdev_target;
 	struct MPT3SAS_TARGET *priv_target = starget->hostdata;
 	char *device_str = NULL;
@@ -3946,9 +4120,7 @@ _scsih_scsi_ioc_info(struct MPT3SAS_ADAPTER *ioc, struct scsi_cmnd *scmd,
 		pr_warn(MPT3SAS_FMT "\t%s wwid(0x%016llx)\n", ioc->name,
 		    device_str, (unsigned long long)priv_target->sas_address);
 	} else {
-		spin_lock_irqsave(&ioc->sas_device_lock, flags);
-		sas_device = mpt3sas_scsih_sas_device_find_by_sas_address(ioc,
-		    priv_target->sas_address);
+		sas_device = mpt3sas_get_sdev_from_target(ioc, priv_target);
 		if (sas_device) {
 			pr_warn(MPT3SAS_FMT
 				"\tsas_address(0x%016llx), phy(%d)\n",
@@ -3967,8 +4139,9 @@ _scsih_scsi_ioc_info(struct MPT3SAS_ADAPTER *ioc, struct scsi_cmnd *scmd,
 				  " connector name( %s)\n", ioc->name,
 				  sas_device->enclosure_level,
 				  sas_device->connector_name);
+
+			sas_device_put(sas_device);
 		}
-		spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
 	}
 
 	pr_warn(MPT3SAS_FMT
@@ -4020,7 +4193,7 @@ _scsih_turn_on_pfa_led(struct MPT3SAS_ADAPTER *ioc, u16 handle)
 	Mpi2SepRequest_t mpi_request;
 	struct _sas_device *sas_device;
 
-	sas_device = _scsih_sas_device_find_by_handle(ioc, handle);
+	sas_device = mpt3sas_get_sdev_by_handle(ioc, handle);
 	if (!sas_device)
 		return;
 
@@ -4035,7 +4208,7 @@ _scsih_turn_on_pfa_led(struct MPT3SAS_ADAPTER *ioc, u16 handle)
 	    &mpi_request)) != 0) {
 		pr_err(MPT3SAS_FMT "failure at %s:%d/%s()!\n", ioc->name,
 		__FILE__, __LINE__, __func__);
-		return;
+		goto out;
 	}
 	sas_device->pfa_led_on = 1;
 
@@ -4044,8 +4217,10 @@ _scsih_turn_on_pfa_led(struct MPT3SAS_ADAPTER *ioc, u16 handle)
 			"enclosure_processor: ioc_status (0x%04x), loginfo(0x%08x)\n",
 			ioc->name, le16_to_cpu(mpi_reply.IOCStatus),
 		    le32_to_cpu(mpi_reply.IOCLogInfo)));
-		return;
+		goto out;
 	}
+out:
+	sas_device_put(sas_device);
 }
 /**
  * _scsih_turn_off_pfa_led - turn off Fault LED
@@ -4098,13 +4273,14 @@ _scsih_send_event_to_turn_on_pfa_led(struct MPT3SAS_ADAPTER *ioc, u16 handle)
 {
 	struct fw_event_work *fw_event;
 
-	fw_event = kzalloc(sizeof(struct fw_event_work), GFP_ATOMIC);
+	fw_event = alloc_fw_event_work(0);
 	if (!fw_event)
 		return;
 	fw_event->event = MPT3SAS_TURN_ON_PFA_LED;
 	fw_event->device_handle = handle;
 	fw_event->ioc = ioc;
 	_scsih_fw_event_add(ioc, fw_event);
+	fw_event_work_put(fw_event);
 }
 
 /**
@@ -4128,19 +4304,17 @@ _scsih_smart_predicted_fault(struct MPT3SAS_ADAPTER *ioc, u16 handle)
 
 	/* only handle non-raid devices */
 	spin_lock_irqsave(&ioc->sas_device_lock, flags);
-	sas_device = _scsih_sas_device_find_by_handle(ioc, handle);
+	sas_device = __mpt3sas_get_sdev_by_handle(ioc, handle);
 	if (!sas_device) {
-		spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
-		return;
+		goto out_unlock;
 	}
 	starget = sas_device->starget;
 	sas_target_priv_data = starget->hostdata;
 
 	if ((sas_target_priv_data->flags & MPT_TARGET_FLAGS_RAID_COMPONENT) ||
-	   ((sas_target_priv_data->flags & MPT_TARGET_FLAGS_VOLUME))) {
-		spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
-		return;
-	}
+	   ((sas_target_priv_data->flags & MPT_TARGET_FLAGS_VOLUME)))
+		goto out_unlock;
+
 	if (sas_device->enclosure_handle != 0)
 		starget_printk(KERN_INFO, starget, "predicted fault, "
 			"enclosure logical id(0x%016llx), slot(%d)\n",
@@ -4163,7 +4337,7 @@ _scsih_smart_predicted_fault(struct MPT3SAS_ADAPTER *ioc, u16 handle)
 	if (!event_reply) {
 		pr_err(MPT3SAS_FMT "failure at %s:%d/%s()!\n",
 		    ioc->name, __FILE__, __LINE__, __func__);
-		return;
+		goto out;
 	}
 
 	event_reply->Function = MPI2_FUNCTION_EVENT_NOTIFICATION;
@@ -4180,6 +4354,14 @@ _scsih_smart_predicted_fault(struct MPT3SAS_ADAPTER *ioc, u16 handle)
 	event_data->SASAddress = cpu_to_le64(sas_target_priv_data->sas_address);
 	mpt3sas_ctl_add_to_event_log(ioc, event_reply);
 	kfree(event_reply);
+out:
+	if (sas_device)
+		sas_device_put(sas_device);
+	return;
+
+out_unlock:
+	spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
+	goto out;
 }
 
 /**
@@ -4933,13 +5115,11 @@ _scsih_check_device(struct MPT3SAS_ADAPTER *ioc,
 
 	spin_lock_irqsave(&ioc->sas_device_lock, flags);
 	sas_address = le64_to_cpu(sas_device_pg0.SASAddress);
-	sas_device = mpt3sas_scsih_sas_device_find_by_sas_address(ioc,
+	sas_device = __mpt3sas_get_sdev_by_addr(ioc,
 	    sas_address);
 
-	if (!sas_device) {
-		spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
-		return;
-	}
+	if (!sas_device)
+		goto out_unlock;
 
 	if (unlikely(sas_device->handle != handle)) {
 		starget = sas_device->starget;
@@ -4967,20 +5147,24 @@ _scsih_check_device(struct MPT3SAS_ADAPTER *ioc,
 		pr_err(MPT3SAS_FMT
 			"device is not present handle(0x%04x), flags!!!\n",
 			ioc->name, handle);
-		spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
-		return;
+		goto out_unlock;
 	}
 
 	/* check if there were any issues with discovery */
 	if (_scsih_check_access_status(ioc, sas_address, handle,
-	    sas_device_pg0.AccessStatus)) {
-		spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
-		return;
-	}
+	    sas_device_pg0.AccessStatus))
+		goto out_unlock;
 
 	spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
 	_scsih_ublock_io_device(ioc, sas_address);
+	if (sas_device)
+		sas_device_put(sas_device);
+	return;
 
+out_unlock:
+	spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
+	if (sas_device)
+		sas_device_put(sas_device);
 }
 
 /**
@@ -5005,7 +5189,6 @@ _scsih_add_device(struct MPT3SAS_ADAPTER *ioc, u16 handle, u8 phy_num,
 	u32 ioc_status;
 	u64 sas_address;
 	u32 device_info;
-	unsigned long flags;
 
 	if ((mpt3sas_config_get_sas_device_pg0(ioc, &mpi_reply, &sas_device_pg0,
 	    MPI2_SAS_DEVICE_PGAD_FORM_HANDLE, handle))) {
@@ -5041,13 +5224,11 @@ _scsih_add_device(struct MPT3SAS_ADAPTER *ioc, u16 handle, u8 phy_num,
 	    sas_device_pg0.AccessStatus))
 		return -1;
 
-	spin_lock_irqsave(&ioc->sas_device_lock, flags);
-	sas_device = mpt3sas_scsih_sas_device_find_by_sas_address(ioc,
-	    sas_address);
-	spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
-
-	if (sas_device)
+	sas_device = mpt3sas_get_sdev_by_addr(ioc, sas_address);
+	if (sas_device) {
+		sas_device_put(sas_device);
 		return -1;
+	}
 
 	sas_device = kzalloc(sizeof(struct _sas_device),
 	    GFP_KERNEL);
@@ -5057,6 +5238,7 @@ _scsih_add_device(struct MPT3SAS_ADAPTER *ioc, u16 handle, u8 phy_num,
 		return 0;
 	}
 
+	kref_init(&sas_device->refcount);
 	sas_device->handle = handle;
 	if (_scsih_get_sas_address(ioc,
 	    le16_to_cpu(sas_device_pg0.ParentDevHandle),
@@ -5098,6 +5280,7 @@ _scsih_add_device(struct MPT3SAS_ADAPTER *ioc, u16 handle, u8 phy_num,
 	else
 		_scsih_sas_device_add(ioc, sas_device);
 
+	sas_device_put(sas_device);
 	return 0;
 }
 
@@ -5506,25 +5689,25 @@ _scsih_sas_device_status_change_event(struct MPT3SAS_ADAPTER *ioc,
 
 	spin_lock_irqsave(&ioc->sas_device_lock, flags);
 	sas_address = le64_to_cpu(event_data->SASAddress);
-	sas_device = mpt3sas_scsih_sas_device_find_by_sas_address(ioc,
-	    sas_address);
+	sas_device = __mpt3sas_get_sdev_by_addr(ioc, sas_address);
 
-	if (!sas_device || !sas_device->starget) {
-		spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
-		return;
-	}
+	if (!sas_device || !sas_device->starget)
+		goto out;
 
 	target_priv_data = sas_device->starget->hostdata;
-	if (!target_priv_data) {
-		spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
-		return;
-	}
+	if (!target_priv_data)
+		goto out;
 
 	if (event_data->ReasonCode ==
 	    MPI2_EVENT_SAS_DEV_STAT_RC_INTERNAL_DEVICE_RESET)
 		target_priv_data->tm_busy = 1;
 	else
 		target_priv_data->tm_busy = 0;
+
+out:
+	if (sas_device)
+		sas_device_put(sas_device);
+
 	spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
 }
 
@@ -6008,7 +6191,7 @@ _scsih_sas_pd_expose(struct MPT3SAS_ADAPTER *ioc,
 	u16 handle = le16_to_cpu(element->PhysDiskDevHandle);
 
 	spin_lock_irqsave(&ioc->sas_device_lock, flags);
-	sas_device = _scsih_sas_device_find_by_handle(ioc, handle);
+	sas_device = __mpt3sas_get_sdev_by_handle(ioc, handle);
 	if (sas_device) {
 		sas_device->volume_handle = 0;
 		sas_device->volume_wwid = 0;
@@ -6027,6 +6210,8 @@ _scsih_sas_pd_expose(struct MPT3SAS_ADAPTER *ioc,
 	/* exposing raid component */
 	if (starget)
 		starget_for_each_device(starget, NULL, _scsih_reprobe_lun);
+
+	sas_device_put(sas_device);
 }
 
 /**
@@ -6055,7 +6240,7 @@ _scsih_sas_pd_hide(struct MPT3SAS_ADAPTER *ioc,
 		    &volume_wwid);
 
 	spin_lock_irqsave(&ioc->sas_device_lock, flags);
-	sas_device = _scsih_sas_device_find_by_handle(ioc, handle);
+	sas_device = __mpt3sas_get_sdev_by_handle(ioc, handle);
 	if (sas_device) {
 		set_bit(handle, ioc->pd_handles);
 		if (sas_device->starget && sas_device->starget->hostdata) {
@@ -6075,6 +6260,8 @@ _scsih_sas_pd_hide(struct MPT3SAS_ADAPTER *ioc,
 	_scsih_ir_fastpath(ioc, handle, element->PhysDiskNum);
 	if (starget)
 		starget_for_each_device(starget, (void *)1, _scsih_reprobe_lun);
+
+	sas_device_put(sas_device);
 }
 
 /**
@@ -6107,7 +6294,6 @@ _scsih_sas_pd_add(struct MPT3SAS_ADAPTER *ioc,
 	Mpi2EventIrConfigElement_t *element)
 {
 	struct _sas_device *sas_device;
-	unsigned long flags;
 	u16 handle = le16_to_cpu(element->PhysDiskDevHandle);
 	Mpi2ConfigReply_t mpi_reply;
 	Mpi2SasDevicePage0_t sas_device_pg0;
@@ -6117,11 +6303,10 @@ _scsih_sas_pd_add(struct MPT3SAS_ADAPTER *ioc,
 
 	set_bit(handle, ioc->pd_handles);
 
-	spin_lock_irqsave(&ioc->sas_device_lock, flags);
-	sas_device = _scsih_sas_device_find_by_handle(ioc, handle);
-	spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
+	sas_device = mpt3sas_get_sdev_by_handle(ioc, handle);
 	if (sas_device) {
 		_scsih_ir_fastpath(ioc, handle, element->PhysDiskNum);
+		sas_device_put(sas_device);
 		return;
 	}
 
@@ -6398,7 +6583,6 @@ _scsih_sas_ir_physical_disk_event(struct MPT3SAS_ADAPTER *ioc,
 	u16 handle, parent_handle;
 	u32 state;
 	struct _sas_device *sas_device;
-	unsigned long flags;
 	Mpi2ConfigReply_t mpi_reply;
 	Mpi2SasDevicePage0_t sas_device_pg0;
 	u32 ioc_status;
@@ -6427,12 +6611,12 @@ _scsih_sas_ir_physical_disk_event(struct MPT3SAS_ADAPTER *ioc,
 	case MPI2_RAID_PD_STATE_HOT_SPARE:
 
 		set_bit(handle, ioc->pd_handles);
-		spin_lock_irqsave(&ioc->sas_device_lock, flags);
-		sas_device = _scsih_sas_device_find_by_handle(ioc, handle);
-		spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
 
-		if (sas_device)
+		sas_device = mpt3sas_get_sdev_by_handle(ioc, handle);
+		if (sas_device) {
+			sas_device_put(sas_device);
 			return;
+		}
 
 		if ((mpt3sas_config_get_sas_device_pg0(ioc, &mpi_reply,
 		    &sas_device_pg0, MPI2_SAS_DEVICE_PGAD_FORM_HANDLE,
@@ -6906,6 +7090,7 @@ _scsih_remove_unresponding_sas_devices(struct MPT3SAS_ADAPTER *ioc)
 	struct _raid_device *raid_device, *raid_device_next;
 	struct list_head tmp_list;
 	unsigned long flags;
+	LIST_HEAD(head);
 
 	pr_info(MPT3SAS_FMT "removing unresponding devices: start\n",
 	    ioc->name);
@@ -6913,14 +7098,29 @@ _scsih_remove_unresponding_sas_devices(struct MPT3SAS_ADAPTER *ioc)
 	/* removing unresponding end devices */
 	pr_info(MPT3SAS_FMT "removing unresponding devices: end-devices\n",
 	    ioc->name);
+
+	/*
+	 * Iterate, pulling off devices marked as non-responding. We become the
+	 * owner for the reference the list had on any object we prune.
+	 */
+	spin_lock_irqsave(&ioc->sas_device_lock, flags);
 	list_for_each_entry_safe(sas_device, sas_device_next,
-	    &ioc->sas_device_list, list) {
+				 &ioc->sas_device_list, list) {
 		if (!sas_device->responding)
-			mpt3sas_device_remove_by_sas_address(ioc,
-			    sas_device->sas_address);
+			list_move_tail(&sas_device->list, &head);
 		else
 			sas_device->responding = 0;
 	}
+	spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
+
+	/*
+	 * Now, uninitialize and remove the unresponding devices we pruned.
+	 */
+	list_for_each_entry_safe(sas_device, sas_device_next, &head, list) {
+		_scsih_remove_device(ioc, sas_device);
+		list_del_init(&sas_device->list);
+		sas_device_put(sas_device);
+	}
 
 	/* removing unresponding volumes */
 	if (ioc->ir_firmware) {
@@ -7074,11 +7274,11 @@ _scsih_scan_for_devices_after_reset(struct MPT3SAS_ADAPTER *ioc)
 		}
 		phys_disk_num = pd_pg0.PhysDiskNum;
 		handle = le16_to_cpu(pd_pg0.DevHandle);
-		spin_lock_irqsave(&ioc->sas_device_lock, flags);
-		sas_device = _scsih_sas_device_find_by_handle(ioc, handle);
-		spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
-		if (sas_device)
+		sas_device = mpt3sas_get_sdev_by_handle(ioc, handle);
+		if (sas_device) {
+			sas_device_put(sas_device);
 			continue;
+		}
 		if (mpt3sas_config_get_sas_device_pg0(ioc, &mpi_reply,
 		    &sas_device_pg0, MPI2_SAS_DEVICE_PGAD_FORM_HANDLE,
 		    handle) != 0)
@@ -7199,12 +7399,12 @@ _scsih_scan_for_devices_after_reset(struct MPT3SAS_ADAPTER *ioc)
 		if (!(_scsih_is_end_device(
 		    le32_to_cpu(sas_device_pg0.DeviceInfo))))
 			continue;
-		spin_lock_irqsave(&ioc->sas_device_lock, flags);
-		sas_device = mpt3sas_scsih_sas_device_find_by_sas_address(ioc,
+		sas_device = mpt3sas_get_sdev_by_addr(ioc,
 		    le64_to_cpu(sas_device_pg0.SASAddress));
-		spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
-		if (sas_device)
+		if (sas_device) {
+			sas_device_put(sas_device);
 			continue;
+		}
 		parent_handle = le16_to_cpu(sas_device_pg0.ParentDevHandle);
 		if (!_scsih_get_sas_address(ioc, parent_handle, &sas_address)) {
 			pr_info(MPT3SAS_FMT "\tBEFORE adding end device: " \
@@ -7296,10 +7496,11 @@ mpt3sas_scsih_reset_handler(struct MPT3SAS_ADAPTER *ioc, int reset_phase)
 static void
 _mpt3sas_fw_work(struct MPT3SAS_ADAPTER *ioc, struct fw_event_work *fw_event)
 {
+	_scsih_fw_event_del_from_list(ioc, fw_event);
+
 	/* the queue is being flushed so ignore this event */
-	if (ioc->remove_host ||
-	    ioc->pci_error_recovery) {
-		_scsih_fw_event_free(ioc, fw_event);
+	if (ioc->remove_host || ioc->pci_error_recovery) {
+		fw_event_work_put(fw_event);
 		return;
 	}
 
@@ -7310,8 +7511,17 @@ _mpt3sas_fw_work(struct MPT3SAS_ADAPTER *ioc, struct fw_event_work *fw_event)
 			fw_event->event_data);
 		break;
 	case MPT3SAS_REMOVE_UNRESPONDING_DEVICES:
-		while (scsi_host_in_recovery(ioc->shost) || ioc->shost_recovery)
+		while (scsi_host_in_recovery(ioc->shost) ||
+				ioc->shost_recovery) {
+			/*
+			 * If we're unloading, bail. Otherwise, this can become
+			 * an infinite loop.
+			 */
+			if (ioc->remove_host)
+				goto out;
+
 			ssleep(1);
+		}
 		_scsih_remove_unresponding_sas_devices(ioc);
 		_scsih_scan_for_devices_after_reset(ioc);
 		break;
@@ -7356,7 +7566,8 @@ _mpt3sas_fw_work(struct MPT3SAS_ADAPTER *ioc, struct fw_event_work *fw_event)
 		_scsih_sas_ir_operation_status_event(ioc, fw_event);
 		break;
 	}
-	_scsih_fw_event_free(ioc, fw_event);
+out:
+	fw_event_work_put(fw_event);
 }
 
 /**
@@ -7472,7 +7683,7 @@ mpt3sas_scsih_event_callback(struct MPT3SAS_ADAPTER *ioc, u8 msix_index,
 	}
 
 	sz = le16_to_cpu(mpi_reply->EventDataLength) * 4;
-	fw_event = kzalloc(sizeof(*fw_event) + sz, GFP_ATOMIC);
+	fw_event = alloc_fw_event_work(sz);
 	if (!fw_event) {
 		pr_err(MPT3SAS_FMT "failure at %s:%d/%s()!\n",
 		    ioc->name, __FILE__, __LINE__, __func__);
@@ -7485,6 +7696,7 @@ mpt3sas_scsih_event_callback(struct MPT3SAS_ADAPTER *ioc, u8 msix_index,
 	fw_event->VP_ID = mpi_reply->VP_ID;
 	fw_event->event = event;
 	_scsih_fw_event_add(ioc, fw_event);
+	fw_event_work_put(fw_event);
 	return 1;
 }
 
@@ -7831,6 +8043,48 @@ _scsih_probe_raid(struct MPT3SAS_ADAPTER *ioc)
 	}
 }
 
+static struct _sas_device *get_next_sas_device(struct MPT3SAS_ADAPTER *ioc)
+{
+	struct _sas_device *sas_device = NULL;
+	unsigned long flags;
+
+	spin_lock_irqsave(&ioc->sas_device_lock, flags);
+	if (!list_empty(&ioc->sas_device_init_list)) {
+		sas_device = list_first_entry(&ioc->sas_device_init_list,
+				struct _sas_device, list);
+		sas_device_get(sas_device);
+	}
+	spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
+
+	return sas_device;
+}
+
+static void sas_device_make_active(struct MPT3SAS_ADAPTER *ioc,
+		struct _sas_device *sas_device)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&ioc->sas_device_lock, flags);
+
+	/*
+	 * Since we dropped the lock during the call to port_add(), we need to
+	 * be careful here that somebody else didn't move or delete this item
+	 * while we were busy with other things.
+	 *
+	 * If it was on the list, we need a put() for the reference the list
+	 * had. Either way, we need a get() for the destination list.
+	 */
+	if (!list_empty(&sas_device->list)) {
+		list_del_init(&sas_device->list);
+		sas_device_put(sas_device);
+	}
+
+	sas_device_get(sas_device);
+	list_add_tail(&sas_device->list, &ioc->sas_device_list);
+
+	spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
+}
+
 /**
  * _scsih_probe_sas - reporting sas devices to sas transport
  * @ioc: per adapter object
@@ -7840,17 +8094,13 @@ _scsih_probe_raid(struct MPT3SAS_ADAPTER *ioc)
 static void
 _scsih_probe_sas(struct MPT3SAS_ADAPTER *ioc)
 {
-	struct _sas_device *sas_device, *next;
-	unsigned long flags;
-
-	/* SAS Device List */
-	list_for_each_entry_safe(sas_device, next, &ioc->sas_device_init_list,
-	    list) {
+	struct _sas_device *sas_device;
 
+	while ((sas_device = get_next_sas_device(ioc))) {
 		if (!mpt3sas_transport_port_add(ioc, sas_device->handle,
-		    sas_device->sas_address_parent)) {
-			list_del(&sas_device->list);
-			kfree(sas_device);
+				sas_device->sas_address_parent)) {
+			_scsih_sas_device_remove(ioc, sas_device);
+			sas_device_put(sas_device);
 			continue;
 		} else if (!sas_device->starget) {
 			/*
@@ -7861,17 +8111,16 @@ _scsih_probe_sas(struct MPT3SAS_ADAPTER *ioc)
 			 */
 			if (!ioc->is_driver_loading) {
 				mpt3sas_transport_port_remove(ioc,
-				    sas_device->sas_address,
-				    sas_device->sas_address_parent);
-				list_del(&sas_device->list);
-				kfree(sas_device);
+						sas_device->sas_address,
+						sas_device->sas_address_parent);
+				_scsih_sas_device_remove(ioc, sas_device);
+				sas_device_put(sas_device);
 				continue;
 			}
 		}
 
-		spin_lock_irqsave(&ioc->sas_device_lock, flags);
-		list_move_tail(&sas_device->list, &ioc->sas_device_list);
-		spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
+		sas_device_make_active(ioc, sas_device);
+		sas_device_put(sas_device);
 	}
 }
 
diff --git a/drivers/scsi/mpt3sas/mpt3sas_transport.c b/drivers/scsi/mpt3sas/mpt3sas_transport.c
index 70fd019e7ee5..ca36d7ea0964 100644
--- a/drivers/scsi/mpt3sas/mpt3sas_transport.c
+++ b/drivers/scsi/mpt3sas/mpt3sas_transport.c
@@ -734,7 +734,7 @@ mpt3sas_transport_port_add(struct MPT3SAS_ADAPTER *ioc, u16 handle,
 	rphy->identify = mpt3sas_port->remote_identify;
 
 	if (mpt3sas_port->remote_identify.device_type == SAS_END_DEVICE) {
-		sas_device = mpt3sas_scsih_sas_device_find_by_sas_address(ioc,
+		sas_device = mpt3sas_get_sdev_by_addr(ioc,
 				    mpt3sas_port->remote_identify.sas_address);
 		if (!sas_device) {
 			dfailprintk(ioc, printk(MPT3SAS_FMT
@@ -750,8 +750,10 @@ mpt3sas_transport_port_add(struct MPT3SAS_ADAPTER *ioc, u16 handle,
 		    ioc->name, __FILE__, __LINE__, __func__);
 	}
 
-	if (mpt3sas_port->remote_identify.device_type == SAS_END_DEVICE)
+	if (mpt3sas_port->remote_identify.device_type == SAS_END_DEVICE) {
 		sas_device->pend_sas_rphy_add = 0;
+		sas_device_put(sas_device);
+	}
 
 	if ((ioc->logging_level & MPT_DEBUG_TRANSPORT))
 		dev_printk(KERN_INFO, &rphy->dev,
@@ -1324,15 +1326,17 @@ _transport_get_enclosure_identifier(struct sas_rphy *rphy, u64 *identifier)
 	int rc;
 
 	spin_lock_irqsave(&ioc->sas_device_lock, flags);
-	sas_device = mpt3sas_scsih_sas_device_find_by_sas_address(ioc,
+	sas_device = __mpt3sas_get_sdev_by_addr(ioc,
 	    rphy->identify.sas_address);
 	if (sas_device) {
 		*identifier = sas_device->enclosure_logical_id;
 		rc = 0;
+		sas_device_put(sas_device);
 	} else {
 		*identifier = 0;
 		rc = -ENXIO;
 	}
+
 	spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
 	return rc;
 }
@@ -1352,12 +1356,14 @@ _transport_get_bay_identifier(struct sas_rphy *rphy)
 	int rc;
 
 	spin_lock_irqsave(&ioc->sas_device_lock, flags);
-	sas_device = mpt3sas_scsih_sas_device_find_by_sas_address(ioc,
+	sas_device = __mpt3sas_get_sdev_by_addr(ioc,
 	    rphy->identify.sas_address);
-	if (sas_device)
+	if (sas_device) {
 		rc = sas_device->slot;
-	else
+		sas_device_put(sas_device);
+	} else {
 		rc = -ENXIO;
+	}
 	spin_unlock_irqrestore(&ioc->sas_device_lock, flags);
 	return rc;
 }