1 files changed, 281 insertions, 185 deletions

diff --git a/drivers/ieee1394/nodemgr.c b/drivers/ieee1394/nodemgr.c
index 8e7b83f84485..61307ca296ae 100644
--- a/drivers/ieee1394/nodemgr.c
+++ b/drivers/ieee1394/nodemgr.c
@@ -14,7 +14,9 @@
 #include <linux/slab.h>
 #include <linux/delay.h>
 #include <linux/kthread.h>
+#include <linux/module.h>
 #include <linux/moduleparam.h>
+#include <linux/freezer.h>
 #include <asm/atomic.h>
 
 #include "csr.h"
@@ -66,7 +68,7 @@ static int nodemgr_check_speed(struct nodemgr_csr_info *ci, u64 addr,
 {
 	quadlet_t q;
 	u8 i, *speed, old_speed, good_speed;
-	int ret;
+	int error;
 
 	speed = &(ci->host->speed[NODEID_TO_NODE(ci->nodeid)]);
 	old_speed = *speed;
@@ -78,9 +80,9 @@ static int nodemgr_check_speed(struct nodemgr_csr_info *ci, u64 addr,
 	 * just finished its initialization. */
 	for (i = IEEE1394_SPEED_100; i <= old_speed; i++) {
 		*speed = i;
-		ret = hpsb_read(ci->host, ci->nodeid, ci->generation, addr,
-				&q, sizeof(quadlet_t));
-		if (ret)
+		error = hpsb_read(ci->host, ci->nodeid, ci->generation, addr,
+				  &q, sizeof(quadlet_t));
+		if (error)
 			break;
 		*buffer = q;
 		good_speed = i;
@@ -94,19 +96,19 @@ static int nodemgr_check_speed(struct nodemgr_csr_info *ci, u64 addr,
 		return 0;
 	}
 	*speed = old_speed;
-	return ret;
+	return error;
 }
 
 static int nodemgr_bus_read(struct csr1212_csr *csr, u64 addr, u16 length,
-                            void *buffer, void *__ci)
+			    void *buffer, void *__ci)
 {
 	struct nodemgr_csr_info *ci = (struct nodemgr_csr_info*)__ci;
-	int i, ret;
+	int i, error;
 
 	for (i = 1; ; i++) {
-		ret = hpsb_read(ci->host, ci->nodeid, ci->generation, addr,
-				buffer, length);
-		if (!ret) {
+		error = hpsb_read(ci->host, ci->nodeid, ci->generation, addr,
+				  buffer, length);
+		if (!error) {
 			ci->speed_unverified = 0;
 			break;
 		}
@@ -117,14 +119,14 @@ static int nodemgr_bus_read(struct csr1212_csr *csr, u64 addr, u16 length,
 		/* The ieee1394_core guessed the node's speed capability from
 		 * the self ID.  Check whether a lower speed works. */
 		if (ci->speed_unverified && length == sizeof(quadlet_t)) {
-			ret = nodemgr_check_speed(ci, addr, buffer);
-			if (!ret)
+			error = nodemgr_check_speed(ci, addr, buffer);
+			if (!error)
 				break;
 		}
 		if (msleep_interruptible(334))
 			return -EINTR;
 	}
-	return ret;
+	return error;
 }
 
 static int nodemgr_get_max_rom(quadlet_t *bus_info_data, void *__ci)
@@ -259,9 +261,20 @@ static struct device nodemgr_dev_template_ne = {
 	.release	= nodemgr_release_ne,
 };
 
+/* This dummy driver prevents the host devices from being scanned. We have no
+ * useful drivers for them yet, and there would be a deadlock possible if the
+ * driver core scans the host device while the host's low-level driver (i.e.
+ * the host's parent device) is being removed. */
+static struct device_driver nodemgr_mid_layer_driver = {
+	.bus		= &ieee1394_bus_type,
+	.name		= "nodemgr",
+	.owner		= THIS_MODULE,
+};
+
 struct device nodemgr_dev_template_host = {
 	.bus		= &ieee1394_bus_type,
 	.release	= nodemgr_release_host,
+	.driver		= &nodemgr_mid_layer_driver,
 };
 
 
@@ -306,8 +319,8 @@ static ssize_t fw_drv_show_##field (struct device_driver *drv, char *buf) \
 	return sprintf(buf, format_string, (type)driver->field);\
 }								\
 static struct driver_attribute driver_attr_drv_##field = {	\
-        .attr = {.name = __stringify(field), .mode = S_IRUGO },	\
-        .show   = fw_drv_show_##field,				\
+	.attr = {.name = __stringify(field), .mode = S_IRUGO },	\
+	.show   = fw_drv_show_##field,				\
 };
 
 
@@ -361,7 +374,7 @@ static ssize_t fw_show_ne_tlabels_mask(struct device *dev,
 #endif
 	spin_unlock_irqrestore(&hpsb_tlabel_lock, flags);
 
-	return sprintf(buf, "0x%016llx\n", tm);
+	return sprintf(buf, "0x%016llx\n", (unsigned long long)tm);
 }
 static DEVICE_ATTR(tlabels_mask, S_IRUGO, fw_show_ne_tlabels_mask, NULL);
 #endif /* HPSB_DEBUG_TLABELS */
@@ -373,11 +386,11 @@ static ssize_t fw_set_ignore_driver(struct device *dev, struct device_attribute
 	int state = simple_strtoul(buf, NULL, 10);
 
 	if (state == 1) {
-		down_write(&dev->bus->subsys.rwsem);
-		device_release_driver(dev);
 		ud->ignore_driver = 1;
-		up_write(&dev->bus->subsys.rwsem);
-	} else if (!state)
+		down_write(&ieee1394_bus_type.subsys.rwsem);
+		device_release_driver(dev);
+		up_write(&ieee1394_bus_type.subsys.rwsem);
+	} else if (state == 0)
 		ud->ignore_driver = 0;
 
 	return count;
@@ -412,11 +425,14 @@ static ssize_t fw_get_destroy_node(struct bus_type *bus, char *buf)
 static BUS_ATTR(destroy_node, S_IWUSR | S_IRUGO, fw_get_destroy_node, fw_set_destroy_node);
 
 
-static ssize_t fw_set_rescan(struct bus_type *bus, const char *buf, size_t count)
+static ssize_t fw_set_rescan(struct bus_type *bus, const char *buf,
+			     size_t count)
 {
+	int error = 0;
+
 	if (simple_strtoul(buf, NULL, 10) == 1)
-		bus_rescan_devices(&ieee1394_bus_type);
-	return count;
+		error = bus_rescan_devices(&ieee1394_bus_type);
+	return error ? error : count;
 }
 static ssize_t fw_get_rescan(struct bus_type *bus, char *buf)
 {
@@ -432,7 +448,7 @@ static ssize_t fw_set_ignore_drivers(struct bus_type *bus, const char *buf, size
 
 	if (state == 1)
 		ignore_drivers = 1;
-	else if (!state)
+	else if (state == 0)
 		ignore_drivers = 0;
 
 	return count;
@@ -525,7 +541,7 @@ static ssize_t fw_show_drv_device_ids(struct device_driver *drv, char *buf)
 	int length = 0;
 	char *scratch = buf;
 
-        driver = container_of(drv, struct hpsb_protocol_driver, driver);
+	driver = container_of(drv, struct hpsb_protocol_driver, driver);
 
 	for (id = driver->id_table; id->match_flags != 0; id++) {
 		int need_coma = 0;
@@ -582,7 +598,11 @@ static void nodemgr_create_drv_files(struct hpsb_protocol_driver *driver)
 	int i;
 
 	for (i = 0; i < ARRAY_SIZE(fw_drv_attrs); i++)
-		driver_create_file(drv, fw_drv_attrs[i]);
+		if (driver_create_file(drv, fw_drv_attrs[i]))
+			goto fail;
+	return;
+fail:
+	HPSB_ERR("Failed to add sysfs attribute for driver %s", driver->name);
 }
 
 
@@ -602,7 +622,12 @@ static void nodemgr_create_ne_dev_files(struct node_entry *ne)
 	int i;
 
 	for (i = 0; i < ARRAY_SIZE(fw_ne_attrs); i++)
-		device_create_file(dev, fw_ne_attrs[i]);
+		if (device_create_file(dev, fw_ne_attrs[i]))
+			goto fail;
+	return;
+fail:
+	HPSB_ERR("Failed to add sysfs attribute for node %016Lx",
+		 (unsigned long long)ne->guid);
 }
 
 
@@ -612,11 +637,16 @@ static void nodemgr_create_host_dev_files(struct hpsb_host *host)
 	int i;
 
 	for (i = 0; i < ARRAY_SIZE(fw_host_attrs); i++)
-		device_create_file(dev, fw_host_attrs[i]);
+		if (device_create_file(dev, fw_host_attrs[i]))
+			goto fail;
+	return;
+fail:
+	HPSB_ERR("Failed to add sysfs attribute for host %d", host->id);
 }
 
 
-static struct node_entry *find_entry_by_nodeid(struct hpsb_host *host, nodeid_t nodeid);
+static struct node_entry *find_entry_by_nodeid(struct hpsb_host *host,
+					       nodeid_t nodeid);
 
 static void nodemgr_update_host_dev_links(struct hpsb_host *host)
 {
@@ -627,12 +657,18 @@ static void nodemgr_update_host_dev_links(struct hpsb_host *host)
 	sysfs_remove_link(&dev->kobj, "busmgr_id");
 	sysfs_remove_link(&dev->kobj, "host_id");
 
-	if ((ne = find_entry_by_nodeid(host, host->irm_id)))
-		sysfs_create_link(&dev->kobj, &ne->device.kobj, "irm_id");
-	if ((ne = find_entry_by_nodeid(host, host->busmgr_id)))
-		sysfs_create_link(&dev->kobj, &ne->device.kobj, "busmgr_id");
-	if ((ne = find_entry_by_nodeid(host, host->node_id)))
-		sysfs_create_link(&dev->kobj, &ne->device.kobj, "host_id");
+	if ((ne = find_entry_by_nodeid(host, host->irm_id)) &&
+	    sysfs_create_link(&dev->kobj, &ne->device.kobj, "irm_id"))
+		goto fail;
+	if ((ne = find_entry_by_nodeid(host, host->busmgr_id)) &&
+	    sysfs_create_link(&dev->kobj, &ne->device.kobj, "busmgr_id"))
+		goto fail;
+	if ((ne = find_entry_by_nodeid(host, host->node_id)) &&
+	    sysfs_create_link(&dev->kobj, &ne->device.kobj, "host_id"))
+		goto fail;
+	return;
+fail:
+	HPSB_ERR("Failed to update sysfs attributes for host %d", host->id);
 }
 
 static void nodemgr_create_ud_dev_files(struct unit_directory *ud)
@@ -641,32 +677,39 @@ static void nodemgr_create_ud_dev_files(struct unit_directory *ud)
 	int i;
 
 	for (i = 0; i < ARRAY_SIZE(fw_ud_attrs); i++)
-		device_create_file(dev, fw_ud_attrs[i]);
-
+		if (device_create_file(dev, fw_ud_attrs[i]))
+			goto fail;
 	if (ud->flags & UNIT_DIRECTORY_SPECIFIER_ID)
-		device_create_file(dev, &dev_attr_ud_specifier_id);
-
+		if (device_create_file(dev, &dev_attr_ud_specifier_id))
+			goto fail;
 	if (ud->flags & UNIT_DIRECTORY_VERSION)
-		device_create_file(dev, &dev_attr_ud_version);
-
+		if (device_create_file(dev, &dev_attr_ud_version))
+			goto fail;
 	if (ud->flags & UNIT_DIRECTORY_VENDOR_ID) {
-		device_create_file(dev, &dev_attr_ud_vendor_id);
-		if (ud->vendor_name_kv)
-			device_create_file(dev, &dev_attr_ud_vendor_name_kv);
+		if (device_create_file(dev, &dev_attr_ud_vendor_id))
+			goto fail;
+		if (ud->vendor_name_kv &&
+		    device_create_file(dev, &dev_attr_ud_vendor_name_kv))
+			goto fail;
 	}
-
 	if (ud->flags & UNIT_DIRECTORY_MODEL_ID) {
-		device_create_file(dev, &dev_attr_ud_model_id);
-		if (ud->model_name_kv)
-			device_create_file(dev, &dev_attr_ud_model_name_kv);
+		if (device_create_file(dev, &dev_attr_ud_model_id))
+			goto fail;
+		if (ud->model_name_kv &&
+		    device_create_file(dev, &dev_attr_ud_model_name_kv))
+			goto fail;
 	}
+	return;
+fail:
+	HPSB_ERR("Failed to add sysfs attributes for unit %s",
+		 ud->device.bus_id);
 }
 
 
 static int nodemgr_bus_match(struct device * dev, struct device_driver * drv)
 {
-        struct hpsb_protocol_driver *driver;
-        struct unit_directory *ud;
+	struct hpsb_protocol_driver *driver;
+	struct unit_directory *ud;
 	struct ieee1394_device_id *id;
 
 	/* We only match unit directories */
@@ -674,55 +717,77 @@ static int nodemgr_bus_match(struct device * dev, struct device_driver * drv)
 		return 0;
 
 	ud = container_of(dev, struct unit_directory, device);
-	driver = container_of(drv, struct hpsb_protocol_driver, driver);
-
 	if (ud->ne->in_limbo || ud->ignore_driver)
 		return 0;
 
-        for (id = driver->id_table; id->match_flags != 0; id++) {
-                if ((id->match_flags & IEEE1394_MATCH_VENDOR_ID) &&
-                    id->vendor_id != ud->vendor_id)
-                        continue;
+	/* We only match drivers of type hpsb_protocol_driver */
+	if (drv == &nodemgr_mid_layer_driver)
+		return 0;
 
-                if ((id->match_flags & IEEE1394_MATCH_MODEL_ID) &&
-                    id->model_id != ud->model_id)
-                        continue;
+	driver = container_of(drv, struct hpsb_protocol_driver, driver);
+	for (id = driver->id_table; id->match_flags != 0; id++) {
+		if ((id->match_flags & IEEE1394_MATCH_VENDOR_ID) &&
+		    id->vendor_id != ud->vendor_id)
+			continue;
 
-                if ((id->match_flags & IEEE1394_MATCH_SPECIFIER_ID) &&
-                    id->specifier_id != ud->specifier_id)
-                        continue;
+		if ((id->match_flags & IEEE1394_MATCH_MODEL_ID) &&
+		    id->model_id != ud->model_id)
+			continue;
 
-                if ((id->match_flags & IEEE1394_MATCH_VERSION) &&
-                    id->version != ud->version)
-                        continue;
+		if ((id->match_flags & IEEE1394_MATCH_SPECIFIER_ID) &&
+		    id->specifier_id != ud->specifier_id)
+			continue;
+
+		if ((id->match_flags & IEEE1394_MATCH_VERSION) &&
+		    id->version != ud->version)
+			continue;
 
 		return 1;
-        }
+	}
 
 	return 0;
 }
 
 
+static DEFINE_MUTEX(nodemgr_serialize_remove_uds);
+
 static void nodemgr_remove_uds(struct node_entry *ne)
 {
-	struct class_device *cdev, *next;
-	struct unit_directory *ud;
-
-	list_for_each_entry_safe(cdev, next, &nodemgr_ud_class.children, node) {
-		ud = container_of(cdev, struct unit_directory, class_dev);
-
-		if (ud->ne != ne)
-			continue;
-
+	struct class_device *cdev;
+	struct unit_directory *tmp, *ud;
+
+	/* Iteration over nodemgr_ud_class.children has to be protected by
+	 * nodemgr_ud_class.sem, but class_device_unregister() will eventually
+	 * take nodemgr_ud_class.sem too. Therefore pick out one ud at a time,
+	 * release the semaphore, and then unregister the ud. Since this code
+	 * may be called from other contexts besides the knodemgrds, protect the
+	 * gap after release of the semaphore by nodemgr_serialize_remove_uds.
+	 */
+	mutex_lock(&nodemgr_serialize_remove_uds);
+	for (;;) {
+		ud = NULL;
+		down(&nodemgr_ud_class.sem);
+		list_for_each_entry(cdev, &nodemgr_ud_class.children, node) {
+			tmp = container_of(cdev, struct unit_directory,
+					   class_dev);
+			if (tmp->ne == ne) {
+				ud = tmp;
+				break;
+			}
+		}
+		up(&nodemgr_ud_class.sem);
+		if (ud == NULL)
+			break;
 		class_device_unregister(&ud->class_dev);
 		device_unregister(&ud->device);
 	}
+	mutex_unlock(&nodemgr_serialize_remove_uds);
 }
 
 
 static void nodemgr_remove_ne(struct node_entry *ne)
 {
-	struct device *dev = &ne->device;
+	struct device *dev;
 
 	dev = get_device(&ne->device);
 	if (!dev)
@@ -747,7 +812,7 @@ static int __nodemgr_remove_host_dev(struct device *dev, void *data)
 
 static void nodemgr_remove_host_dev(struct device *dev)
 {
-	device_for_each_child(dev, NULL, __nodemgr_remove_host_dev);
+	WARN_ON(device_for_each_child(dev, NULL, __nodemgr_remove_host_dev));
 	sysfs_remove_link(&dev->kobj, "irm_id");
 	sysfs_remove_link(&dev->kobj, "busmgr_id");
 	sysfs_remove_link(&dev->kobj, "host_id");
@@ -761,16 +826,16 @@ static void nodemgr_update_bus_options(struct node_entry *ne)
 #endif
 	quadlet_t busoptions = be32_to_cpu(ne->csr->bus_info_data[2]);
 
-	ne->busopt.irmc         = (busoptions >> 31) & 1;
-	ne->busopt.cmc          = (busoptions >> 30) & 1;
-	ne->busopt.isc          = (busoptions >> 29) & 1;
-	ne->busopt.bmc          = (busoptions >> 28) & 1;
-	ne->busopt.pmc          = (busoptions >> 27) & 1;
-	ne->busopt.cyc_clk_acc  = (busoptions >> 16) & 0xff;
-	ne->busopt.max_rec      = 1 << (((busoptions >> 12) & 0xf) + 1);
+	ne->busopt.irmc		= (busoptions >> 31) & 1;
+	ne->busopt.cmc		= (busoptions >> 30) & 1;
+	ne->busopt.isc		= (busoptions >> 29) & 1;
+	ne->busopt.bmc		= (busoptions >> 28) & 1;
+	ne->busopt.pmc		= (busoptions >> 27) & 1;
+	ne->busopt.cyc_clk_acc	= (busoptions >> 16) & 0xff;
+	ne->busopt.max_rec	= 1 << (((busoptions >> 12) & 0xf) + 1);
 	ne->busopt.max_rom	= (busoptions >> 8) & 0x3;
-	ne->busopt.generation   = (busoptions >> 4) & 0xf;
-	ne->busopt.lnkspd       = busoptions & 0x7;
+	ne->busopt.generation	= (busoptions >> 4) & 0xf;
+	ne->busopt.lnkspd	= busoptions & 0x7;
 
 	HPSB_VERBOSE("NodeMgr: raw=0x%08x irmc=%d cmc=%d isc=%d bmc=%d pmc=%d "
 		     "cyc_clk_acc=%d max_rec=%d max_rom=%d gen=%d lspd=%d",
@@ -791,7 +856,7 @@ static struct node_entry *nodemgr_create_node(octlet_t guid, struct csr1212_csr
 
 	ne = kzalloc(sizeof(*ne), GFP_KERNEL);
 	if (!ne)
-		return NULL;
+		goto fail_alloc;
 
 	ne->host = host;
 	ne->nodeid = nodeid;
@@ -814,12 +879,15 @@ static struct node_entry *nodemgr_create_node(octlet_t guid, struct csr1212_csr
 	snprintf(ne->class_dev.class_id, BUS_ID_SIZE, "%016Lx",
 		 (unsigned long long)(ne->guid));
 
-	device_register(&ne->device);
-	class_device_register(&ne->class_dev);
+	if (device_register(&ne->device))
+		goto fail_devreg;
+	if (class_device_register(&ne->class_dev))
+		goto fail_classdevreg;
 	get_device(&ne->device);
 
-	if (ne->guid_vendor_oui)
-		device_create_file(&ne->device, &dev_attr_ne_guid_vendor_oui);
+	if (ne->guid_vendor_oui &&
+	    device_create_file(&ne->device, &dev_attr_ne_guid_vendor_oui))
+		goto fail_addoiu;
 	nodemgr_create_ne_dev_files(ne);
 
 	nodemgr_update_bus_options(ne);
@@ -829,17 +897,28 @@ static struct node_entry *nodemgr_create_node(octlet_t guid, struct csr1212_csr
 		   NODE_BUS_ARGS(host, nodeid), (unsigned long long)guid);
 
 	return ne;
+
+fail_addoiu:
+	put_device(&ne->device);
+fail_classdevreg:
+	device_unregister(&ne->device);
+fail_devreg:
+	kfree(ne);
+fail_alloc:
+	HPSB_ERR("Failed to create node ID:BUS[" NODE_BUS_FMT "]  GUID[%016Lx]",
+		 NODE_BUS_ARGS(host, nodeid), (unsigned long long)guid);
+
+	return NULL;
 }
 
 
 static struct node_entry *find_entry_by_guid(u64 guid)
 {
-	struct class *class = &nodemgr_ne_class;
 	struct class_device *cdev;
 	struct node_entry *ne, *ret_ne = NULL;
 
-	down_read(&class->subsys.rwsem);
-	list_for_each_entry(cdev, &class->children, node) {
+	down(&nodemgr_ne_class.sem);
+	list_for_each_entry(cdev, &nodemgr_ne_class.children, node) {
 		ne = container_of(cdev, struct node_entry, class_dev);
 
 		if (ne->guid == guid) {
@@ -847,20 +926,20 @@ static struct node_entry *find_entry_by_guid(u64 guid)
 			break;
 		}
 	}
-	up_read(&class->subsys.rwsem);
+	up(&nodemgr_ne_class.sem);
 
-        return ret_ne;
+	return ret_ne;
 }
 
 
-static struct node_entry *find_entry_by_nodeid(struct hpsb_host *host, nodeid_t nodeid)
+static struct node_entry *find_entry_by_nodeid(struct hpsb_host *host,
+					       nodeid_t nodeid)
 {
-	struct class *class = &nodemgr_ne_class;
 	struct class_device *cdev;
 	struct node_entry *ne, *ret_ne = NULL;
 
-	down_read(&class->subsys.rwsem);
-	list_for_each_entry(cdev, &class->children, node) {
+	down(&nodemgr_ne_class.sem);
+	list_for_each_entry(cdev, &nodemgr_ne_class.children, node) {
 		ne = container_of(cdev, struct node_entry, class_dev);
 
 		if (ne->host == host && ne->nodeid == nodeid) {
@@ -868,7 +947,7 @@ static struct node_entry *find_entry_by_nodeid(struct hpsb_host *host, nodeid_t
 			break;
 		}
 	}
-	up_read(&class->subsys.rwsem);
+	up(&nodemgr_ne_class.sem);
 
 	return ret_ne;
 }
@@ -890,13 +969,25 @@ static void nodemgr_register_device(struct node_entry *ne,
 	snprintf(ud->class_dev.class_id, BUS_ID_SIZE, "%s-%u",
 		 ne->device.bus_id, ud->id);
 
-	device_register(&ud->device);
-	class_device_register(&ud->class_dev);
+	if (device_register(&ud->device))
+		goto fail_devreg;
+	if (class_device_register(&ud->class_dev))
+		goto fail_classdevreg;
 	get_device(&ud->device);
 
-	if (ud->vendor_oui)
-		device_create_file(&ud->device, &dev_attr_ud_vendor_oui);
+	if (ud->vendor_oui &&
+	    device_create_file(&ud->device, &dev_attr_ud_vendor_oui))
+		goto fail_addoui;
 	nodemgr_create_ud_dev_files(ud);
+
+	return;
+
+fail_addoui:
+	put_device(&ud->device);
+fail_classdevreg:
+	device_unregister(&ud->device);
+fail_devreg:
+	HPSB_ERR("Failed to create unit %s", ud->device.bus_id);
 }	
 
 
@@ -976,10 +1067,9 @@ static struct unit_directory *nodemgr_process_unit_directory
 			/* Logical Unit Number */
 			if (kv->key.type == CSR1212_KV_TYPE_IMMEDIATE) {
 				if (ud->flags & UNIT_DIRECTORY_HAS_LUN) {
-					ud_child = kmalloc(sizeof(*ud_child), GFP_KERNEL);
+					ud_child = kmemdup(ud, sizeof(*ud_child), GFP_KERNEL);
 					if (!ud_child)
 						goto unit_directory_error;
-					memcpy(ud_child, ud, sizeof(*ud_child));
 					nodemgr_register_device(ne, ud_child, &ne->device);
 					ud_child = NULL;
 					
@@ -1093,10 +1183,16 @@ static void nodemgr_process_root_directory(struct host_info *hi, struct node_ent
 		last_key_id = kv->key.id;
 	}
 
-	if (ne->vendor_oui)
-		device_create_file(&ne->device, &dev_attr_ne_vendor_oui);
-	if (ne->vendor_name_kv)
-		device_create_file(&ne->device, &dev_attr_ne_vendor_name_kv);
+	if (ne->vendor_oui &&
+	    device_create_file(&ne->device, &dev_attr_ne_vendor_oui))
+		goto fail;
+	if (ne->vendor_name_kv &&
+	    device_create_file(&ne->device, &dev_attr_ne_vendor_name_kv))
+		goto fail;
+	return;
+fail:
+	HPSB_ERR("Failed to add sysfs attribute for node %016Lx",
+		 (unsigned long long)ne->guid);
 }
 
 #ifdef CONFIG_HOTPLUG
@@ -1160,16 +1256,20 @@ static int nodemgr_uevent(struct class_device *cdev, char **envp, int num_envp,
 #endif /* CONFIG_HOTPLUG */
 
 
-int hpsb_register_protocol(struct hpsb_protocol_driver *driver)
+int __hpsb_register_protocol(struct hpsb_protocol_driver *drv,
+			     struct module *owner)
 {
-	int ret;
+	int error;
 
-	/* This will cause a probe for devices */
-	ret = driver_register(&driver->driver);
-	if (!ret)
-		nodemgr_create_drv_files(driver);
+	drv->driver.bus = &ieee1394_bus_type;
+	drv->driver.owner = owner;
+	drv->driver.name = drv->name;
 
-	return ret;
+	/* This will cause a probe for devices */
+	error = driver_register(&drv->driver);
+	if (!error)
+		nodemgr_create_drv_files(drv);
+	return error;
 }
 
 void hpsb_unregister_protocol(struct hpsb_protocol_driver *driver)
@@ -1297,26 +1397,25 @@ static void nodemgr_node_scan_one(struct host_info *hi,
 
 static void nodemgr_node_scan(struct host_info *hi, int generation)
 {
-        int count;
-        struct hpsb_host *host = hi->host;
-        struct selfid *sid = (struct selfid *)host->topology_map;
-        nodeid_t nodeid = LOCAL_BUS;
+	int count;
+	struct hpsb_host *host = hi->host;
+	struct selfid *sid = (struct selfid *)host->topology_map;
+	nodeid_t nodeid = LOCAL_BUS;
 
-        /* Scan each node on the bus */
-        for (count = host->selfid_count; count; count--, sid++) {
-                if (sid->extended)
-                        continue;
+	/* Scan each node on the bus */
+	for (count = host->selfid_count; count; count--, sid++) {
+		if (sid->extended)
+			continue;
 
-                if (!sid->link_active) {
-                        nodeid++;
-                        continue;
-                }
-                nodemgr_node_scan_one(hi, nodeid++, generation);
-        }
+		if (!sid->link_active) {
+			nodeid++;
+			continue;
+		}
+		nodemgr_node_scan_one(hi, nodeid++, generation);
+	}
 }
 
 
-/* Caller needs to hold nodemgr_ud_class.subsys.rwsem as reader. */
 static void nodemgr_suspend_ne(struct node_entry *ne)
 {
 	struct class_device *cdev;
@@ -1326,21 +1425,22 @@ static void nodemgr_suspend_ne(struct node_entry *ne)
 		   NODE_BUS_ARGS(ne->host, ne->nodeid), (unsigned long long)ne->guid);
 
 	ne->in_limbo = 1;
-	device_create_file(&ne->device, &dev_attr_ne_in_limbo);
+	WARN_ON(device_create_file(&ne->device, &dev_attr_ne_in_limbo));
 
-	down_write(&ne->device.bus->subsys.rwsem);
+	down(&nodemgr_ud_class.sem);
 	list_for_each_entry(cdev, &nodemgr_ud_class.children, node) {
 		ud = container_of(cdev, struct unit_directory, class_dev);
-
 		if (ud->ne != ne)
 			continue;
 
+		down_write(&ieee1394_bus_type.subsys.rwsem);
 		if (ud->device.driver &&
 		    (!ud->device.driver->suspend ||
 		      ud->device.driver->suspend(&ud->device, PMSG_SUSPEND)))
 			device_release_driver(&ud->device);
+		up_write(&ieee1394_bus_type.subsys.rwsem);
 	}
-	up_write(&ne->device.bus->subsys.rwsem);
+	up(&nodemgr_ud_class.sem);
 }
 
 
@@ -1352,45 +1452,47 @@ static void nodemgr_resume_ne(struct node_entry *ne)
 	ne->in_limbo = 0;
 	device_remove_file(&ne->device, &dev_attr_ne_in_limbo);
 
-	down_read(&nodemgr_ud_class.subsys.rwsem);
-	down_read(&ne->device.bus->subsys.rwsem);
+	down(&nodemgr_ud_class.sem);
 	list_for_each_entry(cdev, &nodemgr_ud_class.children, node) {
 		ud = container_of(cdev, struct unit_directory, class_dev);
-
 		if (ud->ne != ne)
 			continue;
 
+		down_read(&ieee1394_bus_type.subsys.rwsem);
 		if (ud->device.driver && ud->device.driver->resume)
 			ud->device.driver->resume(&ud->device);
+		up_read(&ieee1394_bus_type.subsys.rwsem);
 	}
-	up_read(&ne->device.bus->subsys.rwsem);
-	up_read(&nodemgr_ud_class.subsys.rwsem);
+	up(&nodemgr_ud_class.sem);
 
 	HPSB_DEBUG("Node resumed: ID:BUS[" NODE_BUS_FMT "]  GUID[%016Lx]",
 		   NODE_BUS_ARGS(ne->host, ne->nodeid), (unsigned long long)ne->guid);
 }
 
 
-/* Caller needs to hold nodemgr_ud_class.subsys.rwsem as reader. */
 static void nodemgr_update_pdrv(struct node_entry *ne)
 {
 	struct unit_directory *ud;
 	struct hpsb_protocol_driver *pdrv;
 	struct class_device *cdev;
 
+	down(&nodemgr_ud_class.sem);
 	list_for_each_entry(cdev, &nodemgr_ud_class.children, node) {
 		ud = container_of(cdev, struct unit_directory, class_dev);
-		if (ud->ne != ne || !ud->device.driver)
+		if (ud->ne != ne)
 			continue;
 
-		pdrv = container_of(ud->device.driver, struct hpsb_protocol_driver, driver);
-
-		if (pdrv->update && pdrv->update(ud)) {
-			down_write(&ud->device.bus->subsys.rwsem);
-			device_release_driver(&ud->device);
-			up_write(&ud->device.bus->subsys.rwsem);
+		down_write(&ieee1394_bus_type.subsys.rwsem);
+		if (ud->device.driver) {
+			pdrv = container_of(ud->device.driver,
+					    struct hpsb_protocol_driver,
+					    driver);
+			if (pdrv->update && pdrv->update(ud))
+				device_release_driver(&ud->device);
 		}
+		up_write(&ieee1394_bus_type.subsys.rwsem);
 	}
+	up(&nodemgr_ud_class.sem);
 }
 
 
@@ -1404,7 +1506,7 @@ static void nodemgr_irm_write_bc(struct node_entry *ne, int generation)
 {
 	const u64 bc_addr = (CSR_REGISTER_BASE | CSR_BROADCAST_CHANNEL);
 	quadlet_t bc_remote, bc_local;
-	int ret;
+	int error;
 
 	if (!ne->host->is_irm || ne->generation != generation ||
 	    ne->nodeid == ne->host->node_id)
@@ -1413,16 +1515,14 @@ static void nodemgr_irm_write_bc(struct node_entry *ne, int generation)
 	bc_local = cpu_to_be32(ne->host->csr.broadcast_channel);
 
 	/* Check if the register is implemented and 1394a compliant. */
-	ret = hpsb_read(ne->host, ne->nodeid, generation, bc_addr, &bc_remote,
-			sizeof(bc_remote));
-	if (!ret && bc_remote & cpu_to_be32(0x80000000) &&
+	error = hpsb_read(ne->host, ne->nodeid, generation, bc_addr, &bc_remote,
+			  sizeof(bc_remote));
+	if (!error && bc_remote & cpu_to_be32(0x80000000) &&
 	    bc_remote != bc_local)
 		hpsb_node_write(ne, bc_addr, &bc_local, sizeof(bc_local));
 }
 
 
-/* Caller needs to hold nodemgr_ud_class.subsys.rwsem as reader because the
- * calls to nodemgr_update_pdrv() and nodemgr_suspend_ne() here require it. */
 static void nodemgr_probe_ne(struct host_info *hi, struct node_entry *ne, int generation)
 {
 	struct device *dev;
@@ -1455,7 +1555,6 @@ static void nodemgr_probe_ne(struct host_info *hi, struct node_entry *ne, int ge
 static void nodemgr_node_probe(struct host_info *hi, int generation)
 {
 	struct hpsb_host *host = hi->host;
-	struct class *class = &nodemgr_ne_class;
 	struct class_device *cdev;
 	struct node_entry *ne;
 
@@ -1468,18 +1567,18 @@ static void nodemgr_node_probe(struct host_info *hi, int generation)
 	 * while probes are time-consuming. (Well, those probes need some
 	 * improvement...) */
 
-	down_read(&class->subsys.rwsem);
-	list_for_each_entry(cdev, &class->children, node) {
+	down(&nodemgr_ne_class.sem);
+	list_for_each_entry(cdev, &nodemgr_ne_class.children, node) {
 		ne = container_of(cdev, struct node_entry, class_dev);
 		if (!ne->needs_probe)
 			nodemgr_probe_ne(hi, ne, generation);
 	}
-	list_for_each_entry(cdev, &class->children, node) {
+	list_for_each_entry(cdev, &nodemgr_ne_class.children, node) {
 		ne = container_of(cdev, struct node_entry, class_dev);
 		if (ne->needs_probe)
 			nodemgr_probe_ne(hi, ne, generation);
 	}
-        up_read(&class->subsys.rwsem);
+	up(&nodemgr_ne_class.sem);
 
 
 	/* If we had a bus reset while we were scanning the bus, it is
@@ -1497,15 +1596,14 @@ static void nodemgr_node_probe(struct host_info *hi, int generation)
 	 * just removed.  */
 
 	if (generation == get_hpsb_generation(host))
-		bus_rescan_devices(&ieee1394_bus_type);
-
-	return;
+		if (bus_rescan_devices(&ieee1394_bus_type))
+			HPSB_DEBUG("bus_rescan_devices had an error");
 }
 
 static int nodemgr_send_resume_packet(struct hpsb_host *host)
 {
 	struct hpsb_packet *packet;
-	int ret = 1;
+	int error = -ENOMEM;
 
 	packet = hpsb_make_phypacket(host,
 			EXTPHYPACKET_TYPE_RESUME |
@@ -1513,12 +1611,12 @@ static int nodemgr_send_resume_packet(struct hpsb_host *host)
 	if (packet) {
 		packet->no_waiter = 1;
 		packet->generation = get_hpsb_generation(host);
-		ret = hpsb_send_packet(packet);
+		error = hpsb_send_packet(packet);
 	}
-	if (ret)
+	if (error)
 		HPSB_WARN("fw-host%d: Failed to broadcast resume packet",
 			  host->id);
-	return ret;
+	return error;
 }
 
 /* Perform a few high-level IRM responsibilities. */
@@ -1691,19 +1789,18 @@ exit:
 
 int nodemgr_for_each_host(void *__data, int (*cb)(struct hpsb_host *, void *))
 {
-	struct class *class = &hpsb_host_class;
 	struct class_device *cdev;
 	struct hpsb_host *host;
 	int error = 0;
 
-	down_read(&class->subsys.rwsem);
-	list_for_each_entry(cdev, &class->children, node) {
+	down(&hpsb_host_class.sem);
+	list_for_each_entry(cdev, &hpsb_host_class.children, node) {
 		host = container_of(cdev, struct hpsb_host, class_dev);
 
 		if ((error = cb(host, __data)))
 			break;
 	}
-	up_read(&class->subsys.rwsem);
+	up(&hpsb_host_class.sem);
 
 	return error;
 }
@@ -1725,10 +1822,10 @@ int nodemgr_for_each_host(void *__data, int (*cb)(struct hpsb_host *, void *))
 
 void hpsb_node_fill_packet(struct node_entry *ne, struct hpsb_packet *pkt)
 {
-        pkt->host = ne->host;
-        pkt->generation = ne->generation;
+	pkt->host = ne->host;
+	pkt->generation = ne->generation;
 	barrier();
-        pkt->node_id = ne->nodeid;
+	pkt->node_id = ne->nodeid;
 }
 
 int hpsb_node_write(struct node_entry *ne, u64 addr,
@@ -1788,26 +1885,25 @@ static struct hpsb_highlevel nodemgr_highlevel = {
 
 int init_ieee1394_nodemgr(void)
 {
-	int ret;
+	int error;
 
-	ret = class_register(&nodemgr_ne_class);
-	if (ret < 0)
-		return ret;
+	error = class_register(&nodemgr_ne_class);
+	if (error)
+		return error;
 
-	ret = class_register(&nodemgr_ud_class);
-	if (ret < 0) {
+	error = class_register(&nodemgr_ud_class);
+	if (error) {
 		class_unregister(&nodemgr_ne_class);
-		return ret;
+		return error;
 	}
-
+	error = driver_register(&nodemgr_mid_layer_driver);
 	hpsb_register_highlevel(&nodemgr_highlevel);
-
 	return 0;
 }
 
 void cleanup_ieee1394_nodemgr(void)
 {
-        hpsb_unregister_highlevel(&nodemgr_highlevel);
+	hpsb_unregister_highlevel(&nodemgr_highlevel);
 
 	class_unregister(&nodemgr_ud_class);
 	class_unregister(&nodemgr_ne_class);