X-Git-Url: https://gerrit.opnfv.org/gerrit/gitweb?a=blobdiff_plain;f=kernel%2Fdrivers%2Fedac%2Fedac_device_sysfs.c;fp=kernel%2Fdrivers%2Fedac%2Fedac_device_sysfs.c;h=fb68a06ad6837fcce67b3a3baefb98026ad146c3;hb=9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00;hp=0000000000000000000000000000000000000000;hpb=98260f3884f4a202f9ca5eabed40b1354c489b29;p=kvmfornfv.git

diff --git a/kernel/drivers/edac/edac_device_sysfs.c b/kernel/drivers/edac/edac_device_sysfs.c
new file mode 100644
index 000000000..fb68a06ad
--- /dev/null
+++ b/kernel/drivers/edac/edac_device_sysfs.c
@@ -0,0 +1,879 @@
+/*
+ * file for managing the edac_device subsystem of devices for EDAC
+ *
+ * (C) 2007 SoftwareBitMaker 
+ *
+ * This file may be distributed under the terms of the
+ * GNU General Public License.
+ *
+ * Written Doug Thompson <norsk5@xmission.com>
+ *
+ */
+
+#include <linux/ctype.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/edac.h>
+
+#include "edac_core.h"
+#include "edac_module.h"
+
+#define EDAC_DEVICE_SYMLINK	"device"
+
+#define to_edacdev(k) container_of(k, struct edac_device_ctl_info, kobj)
+#define to_edacdev_attr(a) container_of(a, struct edacdev_attribute, attr)
+
+
+/*
+ * Set of edac_device_ctl_info attribute store/show functions
+ */
+
+/* 'log_ue' */
+static ssize_t edac_device_ctl_log_ue_show(struct edac_device_ctl_info
+					*ctl_info, char *data)
+{
+	return sprintf(data, "%u\n", ctl_info->log_ue);
+}
+
+static ssize_t edac_device_ctl_log_ue_store(struct edac_device_ctl_info
+					*ctl_info, const char *data,
+					size_t count)
+{
+	/* if parameter is zero, turn off flag, if non-zero turn on flag */
+	ctl_info->log_ue = (simple_strtoul(data, NULL, 0) != 0);
+
+	return count;
+}
+
+/* 'log_ce' */
+static ssize_t edac_device_ctl_log_ce_show(struct edac_device_ctl_info
+					*ctl_info, char *data)
+{
+	return sprintf(data, "%u\n", ctl_info->log_ce);
+}
+
+static ssize_t edac_device_ctl_log_ce_store(struct edac_device_ctl_info
+					*ctl_info, const char *data,
+					size_t count)
+{
+	/* if parameter is zero, turn off flag, if non-zero turn on flag */
+	ctl_info->log_ce = (simple_strtoul(data, NULL, 0) != 0);
+
+	return count;
+}
+
+/* 'panic_on_ue' */
+static ssize_t edac_device_ctl_panic_on_ue_show(struct edac_device_ctl_info
+						*ctl_info, char *data)
+{
+	return sprintf(data, "%u\n", ctl_info->panic_on_ue);
+}
+
+static ssize_t edac_device_ctl_panic_on_ue_store(struct edac_device_ctl_info
+						 *ctl_info, const char *data,
+						 size_t count)
+{
+	/* if parameter is zero, turn off flag, if non-zero turn on flag */
+	ctl_info->panic_on_ue = (simple_strtoul(data, NULL, 0) != 0);
+
+	return count;
+}
+
+/* 'poll_msec' show and store functions*/
+static ssize_t edac_device_ctl_poll_msec_show(struct edac_device_ctl_info
+					*ctl_info, char *data)
+{
+	return sprintf(data, "%u\n", ctl_info->poll_msec);
+}
+
+static ssize_t edac_device_ctl_poll_msec_store(struct edac_device_ctl_info
+					*ctl_info, const char *data,
+					size_t count)
+{
+	unsigned long value;
+
+	/* get the value and enforce that it is non-zero, must be at least
+	 * one millisecond for the delay period, between scans
+	 * Then cancel last outstanding delay for the work request
+	 * and set a new one.
+	 */
+	value = simple_strtoul(data, NULL, 0);
+	edac_device_reset_delay_period(ctl_info, value);
+
+	return count;
+}
+
+/* edac_device_ctl_info specific attribute structure */
+struct ctl_info_attribute {
+	struct attribute attr;
+	ssize_t(*show) (struct edac_device_ctl_info *, char *);
+	ssize_t(*store) (struct edac_device_ctl_info *, const char *, size_t);
+};
+
+#define to_ctl_info(k) container_of(k, struct edac_device_ctl_info, kobj)
+#define to_ctl_info_attr(a) container_of(a,struct ctl_info_attribute,attr)
+
+/* Function to 'show' fields from the edac_dev 'ctl_info' structure */
+static ssize_t edac_dev_ctl_info_show(struct kobject *kobj,
+				struct attribute *attr, char *buffer)
+{
+	struct edac_device_ctl_info *edac_dev = to_ctl_info(kobj);
+	struct ctl_info_attribute *ctl_info_attr = to_ctl_info_attr(attr);
+
+	if (ctl_info_attr->show)
+		return ctl_info_attr->show(edac_dev, buffer);
+	return -EIO;
+}
+
+/* Function to 'store' fields into the edac_dev 'ctl_info' structure */
+static ssize_t edac_dev_ctl_info_store(struct kobject *kobj,
+				struct attribute *attr,
+				const char *buffer, size_t count)
+{
+	struct edac_device_ctl_info *edac_dev = to_ctl_info(kobj);
+	struct ctl_info_attribute *ctl_info_attr = to_ctl_info_attr(attr);
+
+	if (ctl_info_attr->store)
+		return ctl_info_attr->store(edac_dev, buffer, count);
+	return -EIO;
+}
+
+/* edac_dev file operations for an 'ctl_info' */
+static const struct sysfs_ops device_ctl_info_ops = {
+	.show = edac_dev_ctl_info_show,
+	.store = edac_dev_ctl_info_store
+};
+
+#define CTL_INFO_ATTR(_name,_mode,_show,_store)        \
+static struct ctl_info_attribute attr_ctl_info_##_name = {      \
+	.attr = {.name = __stringify(_name), .mode = _mode },   \
+	.show   = _show,                                        \
+	.store  = _store,                                       \
+};
+
+/* Declare the various ctl_info attributes here and their respective ops */
+CTL_INFO_ATTR(log_ue, S_IRUGO | S_IWUSR,
+	edac_device_ctl_log_ue_show, edac_device_ctl_log_ue_store);
+CTL_INFO_ATTR(log_ce, S_IRUGO | S_IWUSR,
+	edac_device_ctl_log_ce_show, edac_device_ctl_log_ce_store);
+CTL_INFO_ATTR(panic_on_ue, S_IRUGO | S_IWUSR,
+	edac_device_ctl_panic_on_ue_show,
+	edac_device_ctl_panic_on_ue_store);
+CTL_INFO_ATTR(poll_msec, S_IRUGO | S_IWUSR,
+	edac_device_ctl_poll_msec_show, edac_device_ctl_poll_msec_store);
+
+/* Base Attributes of the EDAC_DEVICE ECC object */
+static struct ctl_info_attribute *device_ctrl_attr[] = {
+	&attr_ctl_info_panic_on_ue,
+	&attr_ctl_info_log_ue,
+	&attr_ctl_info_log_ce,
+	&attr_ctl_info_poll_msec,
+	NULL,
+};
+
+/*
+ * edac_device_ctrl_master_release
+ *
+ *	called when the reference count for the 'main' kobj
+ *	for a edac_device control struct reaches zero
+ *
+ *	Reference count model:
+ *		One 'main' kobject for each control structure allocated.
+ *		That main kobj is initially set to one AND
+ *		the reference count for the EDAC 'core' module is
+ *		bumped by one, thus added 'keep in memory' dependency.
+ *
+ *		Each new internal kobj (in instances and blocks) then
+ *		bumps the 'main' kobject.
+ *
+ *		When they are released their release functions decrement
+ *		the 'main' kobj.
+ *
+ *		When the main kobj reaches zero (0) then THIS function
+ *		is called which then decrements the EDAC 'core' module.
+ *		When the module reference count reaches zero then the
+ *		module no longer has dependency on keeping the release
+ *		function code in memory and module can be unloaded.
+ *
+ *		This will support several control objects as well, each
+ *		with its own 'main' kobj.
+ */
+static void edac_device_ctrl_master_release(struct kobject *kobj)
+{
+	struct edac_device_ctl_info *edac_dev = to_edacdev(kobj);
+
+	edac_dbg(4, "control index=%d\n", edac_dev->dev_idx);
+
+	/* decrement the EDAC CORE module ref count */
+	module_put(edac_dev->owner);
+
+	/* free the control struct containing the 'main' kobj
+	 * passed in to this routine
+	 */
+	kfree(edac_dev);
+}
+
+/* ktype for the main (master) kobject */
+static struct kobj_type ktype_device_ctrl = {
+	.release = edac_device_ctrl_master_release,
+	.sysfs_ops = &device_ctl_info_ops,
+	.default_attrs = (struct attribute **)device_ctrl_attr,
+};
+
+/*
+ * edac_device_register_sysfs_main_kobj
+ *
+ *	perform the high level setup for the new edac_device instance
+ *
+ * Return:  0 SUCCESS
+ *         !0 FAILURE
+ */
+int edac_device_register_sysfs_main_kobj(struct edac_device_ctl_info *edac_dev)
+{
+	struct bus_type *edac_subsys;
+	int err;
+
+	edac_dbg(1, "\n");
+
+	/* get the /sys/devices/system/edac reference */
+	edac_subsys = edac_get_sysfs_subsys();
+	if (edac_subsys == NULL) {
+		edac_dbg(1, "no edac_subsys error\n");
+		err = -ENODEV;
+		goto err_out;
+	}
+
+	/* Point to the 'edac_subsys' this instance 'reports' to */
+	edac_dev->edac_subsys = edac_subsys;
+
+	/* Init the devices's kobject */
+	memset(&edac_dev->kobj, 0, sizeof(struct kobject));
+
+	/* Record which module 'owns' this control structure
+	 * and bump the ref count of the module
+	 */
+	edac_dev->owner = THIS_MODULE;
+
+	if (!try_module_get(edac_dev->owner)) {
+		err = -ENODEV;
+		goto err_mod_get;
+	}
+
+	/* register */
+	err = kobject_init_and_add(&edac_dev->kobj, &ktype_device_ctrl,
+				   &edac_subsys->dev_root->kobj,
+				   "%s", edac_dev->name);
+	if (err) {
+		edac_dbg(1, "Failed to register '.../edac/%s'\n",
+			 edac_dev->name);
+		goto err_kobj_reg;
+	}
+	kobject_uevent(&edac_dev->kobj, KOBJ_ADD);
+
+	/* At this point, to 'free' the control struct,
+	 * edac_device_unregister_sysfs_main_kobj() must be used
+	 */
+
+	edac_dbg(4, "Registered '.../edac/%s' kobject\n", edac_dev->name);
+
+	return 0;
+
+	/* Error exit stack */
+err_kobj_reg:
+	module_put(edac_dev->owner);
+
+err_mod_get:
+	edac_put_sysfs_subsys();
+
+err_out:
+	return err;
+}
+
+/*
+ * edac_device_unregister_sysfs_main_kobj:
+ *	the '..../edac/<name>' kobject
+ */
+void edac_device_unregister_sysfs_main_kobj(struct edac_device_ctl_info *dev)
+{
+	edac_dbg(0, "\n");
+	edac_dbg(4, "name of kobject is: %s\n", kobject_name(&dev->kobj));
+
+	/*
+	 * Unregister the edac device's kobject and
+	 * allow for reference count to reach 0 at which point
+	 * the callback will be called to:
+	 *   a) module_put() this module
+	 *   b) 'kfree' the memory
+	 */
+	kobject_put(&dev->kobj);
+	edac_put_sysfs_subsys();
+}
+
+/* edac_dev -> instance information */
+
+/*
+ * Set of low-level instance attribute show functions
+ */
+static ssize_t instance_ue_count_show(struct edac_device_instance *instance,
+				char *data)
+{
+	return sprintf(data, "%u\n", instance->counters.ue_count);
+}
+
+static ssize_t instance_ce_count_show(struct edac_device_instance *instance,
+				char *data)
+{
+	return sprintf(data, "%u\n", instance->counters.ce_count);
+}
+
+#define to_instance(k) container_of(k, struct edac_device_instance, kobj)
+#define to_instance_attr(a) container_of(a,struct instance_attribute,attr)
+
+/* DEVICE instance kobject release() function */
+static void edac_device_ctrl_instance_release(struct kobject *kobj)
+{
+	struct edac_device_instance *instance;
+
+	edac_dbg(1, "\n");
+
+	/* map from this kobj to the main control struct
+	 * and then dec the main kobj count
+	 */
+	instance = to_instance(kobj);
+	kobject_put(&instance->ctl->kobj);
+}
+
+/* instance specific attribute structure */
+struct instance_attribute {
+	struct attribute attr;
+	ssize_t(*show) (struct edac_device_instance *, char *);
+	ssize_t(*store) (struct edac_device_instance *, const char *, size_t);
+};
+
+/* Function to 'show' fields from the edac_dev 'instance' structure */
+static ssize_t edac_dev_instance_show(struct kobject *kobj,
+				struct attribute *attr, char *buffer)
+{
+	struct edac_device_instance *instance = to_instance(kobj);
+	struct instance_attribute *instance_attr = to_instance_attr(attr);
+
+	if (instance_attr->show)
+		return instance_attr->show(instance, buffer);
+	return -EIO;
+}
+
+/* Function to 'store' fields into the edac_dev 'instance' structure */
+static ssize_t edac_dev_instance_store(struct kobject *kobj,
+				struct attribute *attr,
+				const char *buffer, size_t count)
+{
+	struct edac_device_instance *instance = to_instance(kobj);
+	struct instance_attribute *instance_attr = to_instance_attr(attr);
+
+	if (instance_attr->store)
+		return instance_attr->store(instance, buffer, count);
+	return -EIO;
+}
+
+/* edac_dev file operations for an 'instance' */
+static const struct sysfs_ops device_instance_ops = {
+	.show = edac_dev_instance_show,
+	.store = edac_dev_instance_store
+};
+
+#define INSTANCE_ATTR(_name,_mode,_show,_store)        \
+static struct instance_attribute attr_instance_##_name = {      \
+	.attr = {.name = __stringify(_name), .mode = _mode },   \
+	.show   = _show,                                        \
+	.store  = _store,                                       \
+};
+
+/*
+ * Define attributes visible for the edac_device instance object
+ *	Each contains a pointer to a show and an optional set
+ *	function pointer that does the low level output/input
+ */
+INSTANCE_ATTR(ce_count, S_IRUGO, instance_ce_count_show, NULL);
+INSTANCE_ATTR(ue_count, S_IRUGO, instance_ue_count_show, NULL);
+
+/* list of edac_dev 'instance' attributes */
+static struct instance_attribute *device_instance_attr[] = {
+	&attr_instance_ce_count,
+	&attr_instance_ue_count,
+	NULL,
+};
+
+/* The 'ktype' for each edac_dev 'instance' */
+static struct kobj_type ktype_instance_ctrl = {
+	.release = edac_device_ctrl_instance_release,
+	.sysfs_ops = &device_instance_ops,
+	.default_attrs = (struct attribute **)device_instance_attr,
+};
+
+/* edac_dev -> instance -> block information */
+
+#define to_block(k) container_of(k, struct edac_device_block, kobj)
+#define to_block_attr(a) \
+	container_of(a, struct edac_dev_sysfs_block_attribute, attr)
+
+/*
+ * Set of low-level block attribute show functions
+ */
+static ssize_t block_ue_count_show(struct kobject *kobj,
+					struct attribute *attr, char *data)
+{
+	struct edac_device_block *block = to_block(kobj);
+
+	return sprintf(data, "%u\n", block->counters.ue_count);
+}
+
+static ssize_t block_ce_count_show(struct kobject *kobj,
+					struct attribute *attr, char *data)
+{
+	struct edac_device_block *block = to_block(kobj);
+
+	return sprintf(data, "%u\n", block->counters.ce_count);
+}
+
+/* DEVICE block kobject release() function */
+static void edac_device_ctrl_block_release(struct kobject *kobj)
+{
+	struct edac_device_block *block;
+
+	edac_dbg(1, "\n");
+
+	/* get the container of the kobj */
+	block = to_block(kobj);
+
+	/* map from 'block kobj' to 'block->instance->controller->main_kobj'
+	 * now 'release' the block kobject
+	 */
+	kobject_put(&block->instance->ctl->kobj);
+}
+
+
+/* Function to 'show' fields from the edac_dev 'block' structure */
+static ssize_t edac_dev_block_show(struct kobject *kobj,
+				struct attribute *attr, char *buffer)
+{
+	struct edac_dev_sysfs_block_attribute *block_attr =
+						to_block_attr(attr);
+
+	if (block_attr->show)
+		return block_attr->show(kobj, attr, buffer);
+	return -EIO;
+}
+
+/* Function to 'store' fields into the edac_dev 'block' structure */
+static ssize_t edac_dev_block_store(struct kobject *kobj,
+				struct attribute *attr,
+				const char *buffer, size_t count)
+{
+	struct edac_dev_sysfs_block_attribute *block_attr;
+
+	block_attr = to_block_attr(attr);
+
+	if (block_attr->store)
+		return block_attr->store(kobj, attr, buffer, count);
+	return -EIO;
+}
+
+/* edac_dev file operations for a 'block' */
+static const struct sysfs_ops device_block_ops = {
+	.show = edac_dev_block_show,
+	.store = edac_dev_block_store
+};
+
+#define BLOCK_ATTR(_name,_mode,_show,_store)        \
+static struct edac_dev_sysfs_block_attribute attr_block_##_name = {	\
+	.attr = {.name = __stringify(_name), .mode = _mode },   \
+	.show   = _show,                                        \
+	.store  = _store,                                       \
+};
+
+BLOCK_ATTR(ce_count, S_IRUGO, block_ce_count_show, NULL);
+BLOCK_ATTR(ue_count, S_IRUGO, block_ue_count_show, NULL);
+
+/* list of edac_dev 'block' attributes */
+static struct edac_dev_sysfs_block_attribute *device_block_attr[] = {
+	&attr_block_ce_count,
+	&attr_block_ue_count,
+	NULL,
+};
+
+/* The 'ktype' for each edac_dev 'block' */
+static struct kobj_type ktype_block_ctrl = {
+	.release = edac_device_ctrl_block_release,
+	.sysfs_ops = &device_block_ops,
+	.default_attrs = (struct attribute **)device_block_attr,
+};
+
+/* block ctor/dtor  code */
+
+/*
+ * edac_device_create_block
+ */
+static int edac_device_create_block(struct edac_device_ctl_info *edac_dev,
+				struct edac_device_instance *instance,
+				struct edac_device_block *block)
+{
+	int i;
+	int err;
+	struct edac_dev_sysfs_block_attribute *sysfs_attrib;
+	struct kobject *main_kobj;
+
+	edac_dbg(4, "Instance '%s' inst_p=%p  block '%s'  block_p=%p\n",
+		 instance->name, instance, block->name, block);
+	edac_dbg(4, "block kobj=%p  block kobj->parent=%p\n",
+		 &block->kobj, &block->kobj.parent);
+
+	/* init this block's kobject */
+	memset(&block->kobj, 0, sizeof(struct kobject));
+
+	/* bump the main kobject's reference count for this controller
+	 * and this instance is dependent on the main
+	 */
+	main_kobj = kobject_get(&edac_dev->kobj);
+	if (!main_kobj) {
+		err = -ENODEV;
+		goto err_out;
+	}
+
+	/* Add this block's kobject */
+	err = kobject_init_and_add(&block->kobj, &ktype_block_ctrl,
+				   &instance->kobj,
+				   "%s", block->name);
+	if (err) {
+		edac_dbg(1, "Failed to register instance '%s'\n", block->name);
+		kobject_put(main_kobj);
+		err = -ENODEV;
+		goto err_out;
+	}
+
+	/* If there are driver level block attributes, then added them
+	 * to the block kobject
+	 */
+	sysfs_attrib = block->block_attributes;
+	if (sysfs_attrib && block->nr_attribs) {
+		for (i = 0; i < block->nr_attribs; i++, sysfs_attrib++) {
+
+			edac_dbg(4, "creating block attrib='%s' attrib->%p to kobj=%p\n",
+				 sysfs_attrib->attr.name,
+				 sysfs_attrib, &block->kobj);
+
+			/* Create each block_attribute file */
+			err = sysfs_create_file(&block->kobj,
+				&sysfs_attrib->attr);
+			if (err)
+				goto err_on_attrib;
+		}
+	}
+	kobject_uevent(&block->kobj, KOBJ_ADD);
+
+	return 0;
+
+	/* Error unwind stack */
+err_on_attrib:
+	kobject_put(&block->kobj);
+
+err_out:
+	return err;
+}
+
+/*
+ * edac_device_delete_block(edac_dev,block);
+ */
+static void edac_device_delete_block(struct edac_device_ctl_info *edac_dev,
+				struct edac_device_block *block)
+{
+	struct edac_dev_sysfs_block_attribute *sysfs_attrib;
+	int i;
+
+	/* if this block has 'attributes' then we need to iterate over the list
+	 * and 'remove' the attributes on this block
+	 */
+	sysfs_attrib = block->block_attributes;
+	if (sysfs_attrib && block->nr_attribs) {
+		for (i = 0; i < block->nr_attribs; i++, sysfs_attrib++) {
+
+			/* remove each block_attrib file */
+			sysfs_remove_file(&block->kobj,
+				(struct attribute *) sysfs_attrib);
+		}
+	}
+
+	/* unregister this block's kobject, SEE:
+	 *	edac_device_ctrl_block_release() callback operation
+	 */
+	kobject_put(&block->kobj);
+}
+
+/* instance ctor/dtor code */
+
+/*
+ * edac_device_create_instance
+ *	create just one instance of an edac_device 'instance'
+ */
+static int edac_device_create_instance(struct edac_device_ctl_info *edac_dev,
+				int idx)
+{
+	int i, j;
+	int err;
+	struct edac_device_instance *instance;
+	struct kobject *main_kobj;
+
+	instance = &edac_dev->instances[idx];
+
+	/* Init the instance's kobject */
+	memset(&instance->kobj, 0, sizeof(struct kobject));
+
+	instance->ctl = edac_dev;
+
+	/* bump the main kobject's reference count for this controller
+	 * and this instance is dependent on the main
+	 */
+	main_kobj = kobject_get(&edac_dev->kobj);
+	if (!main_kobj) {
+		err = -ENODEV;
+		goto err_out;
+	}
+
+	/* Formally register this instance's kobject under the edac_device */
+	err = kobject_init_and_add(&instance->kobj, &ktype_instance_ctrl,
+				   &edac_dev->kobj, "%s", instance->name);
+	if (err != 0) {
+		edac_dbg(2, "Failed to register instance '%s'\n",
+			 instance->name);
+		kobject_put(main_kobj);
+		goto err_out;
+	}
+
+	edac_dbg(4, "now register '%d' blocks for instance %d\n",
+		 instance->nr_blocks, idx);
+
+	/* register all blocks of this instance */
+	for (i = 0; i < instance->nr_blocks; i++) {
+		err = edac_device_create_block(edac_dev, instance,
+						&instance->blocks[i]);
+		if (err) {
+			/* If any fail, remove all previous ones */
+			for (j = 0; j < i; j++)
+				edac_device_delete_block(edac_dev,
+							&instance->blocks[j]);
+			goto err_release_instance_kobj;
+		}
+	}
+	kobject_uevent(&instance->kobj, KOBJ_ADD);
+
+	edac_dbg(4, "Registered instance %d '%s' kobject\n",
+		 idx, instance->name);
+
+	return 0;
+
+	/* error unwind stack */
+err_release_instance_kobj:
+	kobject_put(&instance->kobj);
+
+err_out:
+	return err;
+}
+
+/*
+ * edac_device_remove_instance
+ *	remove an edac_device instance
+ */
+static void edac_device_delete_instance(struct edac_device_ctl_info *edac_dev,
+					int idx)
+{
+	struct edac_device_instance *instance;
+	int i;
+
+	instance = &edac_dev->instances[idx];
+
+	/* unregister all blocks in this instance */
+	for (i = 0; i < instance->nr_blocks; i++)
+		edac_device_delete_block(edac_dev, &instance->blocks[i]);
+
+	/* unregister this instance's kobject, SEE:
+	 *	edac_device_ctrl_instance_release() for callback operation
+	 */
+	kobject_put(&instance->kobj);
+}
+
+/*
+ * edac_device_create_instances
+ *	create the first level of 'instances' for this device
+ *	(ie  'cache' might have 'cache0', 'cache1', 'cache2', etc
+ */
+static int edac_device_create_instances(struct edac_device_ctl_info *edac_dev)
+{
+	int i, j;
+	int err;
+
+	edac_dbg(0, "\n");
+
+	/* iterate over creation of the instances */
+	for (i = 0; i < edac_dev->nr_instances; i++) {
+		err = edac_device_create_instance(edac_dev, i);
+		if (err) {
+			/* unwind previous instances on error */
+			for (j = 0; j < i; j++)
+				edac_device_delete_instance(edac_dev, j);
+			return err;
+		}
+	}
+
+	return 0;
+}
+
+/*
+ * edac_device_delete_instances(edac_dev);
+ *	unregister all the kobjects of the instances
+ */
+static void edac_device_delete_instances(struct edac_device_ctl_info *edac_dev)
+{
+	int i;
+
+	/* iterate over creation of the instances */
+	for (i = 0; i < edac_dev->nr_instances; i++)
+		edac_device_delete_instance(edac_dev, i);
+}
+
+/* edac_dev sysfs ctor/dtor  code */
+
+/*
+ * edac_device_add_main_sysfs_attributes
+ *	add some attributes to this instance's main kobject
+ */
+static int edac_device_add_main_sysfs_attributes(
+			struct edac_device_ctl_info *edac_dev)
+{
+	struct edac_dev_sysfs_attribute *sysfs_attrib;
+	int err = 0;
+
+	sysfs_attrib = edac_dev->sysfs_attributes;
+	if (sysfs_attrib) {
+		/* iterate over the array and create an attribute for each
+		 * entry in the list
+		 */
+		while (sysfs_attrib->attr.name != NULL) {
+			err = sysfs_create_file(&edac_dev->kobj,
+				(struct attribute*) sysfs_attrib);
+			if (err)
+				goto err_out;
+
+			sysfs_attrib++;
+		}
+	}
+
+err_out:
+	return err;
+}
+
+/*
+ * edac_device_remove_main_sysfs_attributes
+ *	remove any attributes to this instance's main kobject
+ */
+static void edac_device_remove_main_sysfs_attributes(
+			struct edac_device_ctl_info *edac_dev)
+{
+	struct edac_dev_sysfs_attribute *sysfs_attrib;
+
+	/* if there are main attributes, defined, remove them. First,
+	 * point to the start of the array and iterate over it
+	 * removing each attribute listed from this device's instance's kobject
+	 */
+	sysfs_attrib = edac_dev->sysfs_attributes;
+	if (sysfs_attrib) {
+		while (sysfs_attrib->attr.name != NULL) {
+			sysfs_remove_file(&edac_dev->kobj,
+					(struct attribute *) sysfs_attrib);
+			sysfs_attrib++;
+		}
+	}
+}
+
+/*
+ * edac_device_create_sysfs() Constructor
+ *
+ * accept a created edac_device control structure
+ * and 'export' it to sysfs. The 'main' kobj should already have been
+ * created. 'instance' and 'block' kobjects should be registered
+ * along with any 'block' attributes from the low driver. In addition,
+ * the main attributes (if any) are connected to the main kobject of
+ * the control structure.
+ *
+ * Return:
+ *	0	Success
+ *	!0	Failure
+ */
+int edac_device_create_sysfs(struct edac_device_ctl_info *edac_dev)
+{
+	int err;
+	struct kobject *edac_kobj = &edac_dev->kobj;
+
+	edac_dbg(0, "idx=%d\n", edac_dev->dev_idx);
+
+	/*  go create any main attributes callers wants */
+	err = edac_device_add_main_sysfs_attributes(edac_dev);
+	if (err) {
+		edac_dbg(0, "failed to add sysfs attribs\n");
+		goto err_out;
+	}
+
+	/* create a symlink from the edac device
+	 * to the platform 'device' being used for this
+	 */
+	err = sysfs_create_link(edac_kobj,
+				&edac_dev->dev->kobj, EDAC_DEVICE_SYMLINK);
+	if (err) {
+		edac_dbg(0, "sysfs_create_link() returned err= %d\n", err);
+		goto err_remove_main_attribs;
+	}
+
+	/* Create the first level instance directories
+	 * In turn, the nested blocks beneath the instances will
+	 * be registered as well
+	 */
+	err = edac_device_create_instances(edac_dev);
+	if (err) {
+		edac_dbg(0, "edac_device_create_instances() returned err= %d\n",
+			 err);
+		goto err_remove_link;
+	}
+
+
+	edac_dbg(4, "create-instances done, idx=%d\n", edac_dev->dev_idx);
+
+	return 0;
+
+	/* Error unwind stack */
+err_remove_link:
+	/* remove the sym link */
+	sysfs_remove_link(&edac_dev->kobj, EDAC_DEVICE_SYMLINK);
+
+err_remove_main_attribs:
+	edac_device_remove_main_sysfs_attributes(edac_dev);
+
+err_out:
+	return err;
+}
+
+/*
+ * edac_device_remove_sysfs() destructor
+ *
+ * given an edac_device struct, tear down the kobject resources
+ */
+void edac_device_remove_sysfs(struct edac_device_ctl_info *edac_dev)
+{
+	edac_dbg(0, "\n");
+
+	/* remove any main attributes for this device */
+	edac_device_remove_main_sysfs_attributes(edac_dev);
+
+	/* remove the device sym link */
+	sysfs_remove_link(&edac_dev->kobj, EDAC_DEVICE_SYMLINK);
+
+	/* walk the instance/block kobject tree, deconstructing it */
+	edac_device_delete_instances(edac_dev);
+}