convert 'memory' sysdev_class to a regular subsystem

This moves the 'memory sysdev_class' over to a regular 'memory' subsystem
and converts the devices to regular devices. The sysdev drivers are
implemented as subsystem interfaces now.

After all sysdev classes are ported to regular driver core entities, the
sysdev implementation will be entirely removed from the kernel.

Signed-off-by: Kay Sievers <[e-mail]>
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

arch/powerpc/kernel/sysfs.c

···
 int sysfs_add_device_to_node(struct device *dev, int nid)
 {
 	struct node *node = &node_devices[nid];
-	return sysfs_create_link(&node->sysdev.kobj, &dev->kobj,
+	return sysfs_create_link(&node->dev.kobj, &dev->kobj,
 			kobject_name(&dev->kobj));
 }
 EXPORT_SYMBOL_GPL(sysfs_add_device_to_node);
···
 void sysfs_remove_device_from_node(struct device *dev, int nid)
 {
 	struct node *node = &node_devices[nid];
-	sysfs_remove_link(&node->sysdev.kobj, kobject_name(&dev->kobj));
+	sysfs_remove_link(&node->dev.kobj, kobject_name(&dev->kobj));
 }
 EXPORT_SYMBOL_GPL(sysfs_remove_device_from_node);
 

drivers/base/memory.c

···
 /*
- * drivers/base/memory.c - basic Memory class support
+ * Memory subsystem support
  *
  * Written by Matt Tolentino <[e-mail]>
  *            Dave Hansen <[e-mail]>
···
  * SPARSEMEM should be contained here, or in mm/memory_hotplug.c.
  */
 
-#include <linux/sysdev.h>
 #include <linux/module.h>
 #include <linux/init.h>
 #include <linux/topology.h>
···
 	return section_nr / sections_per_block;
 }
 
-static struct sysdev_class memory_sysdev_class = {
+static struct bus_type memory_subsys = {
 	.name = MEMORY_CLASS_NAME,
-};
-
-static const char *memory_uevent_name(struct kset *kset, struct kobject *kobj)
-{
-	return MEMORY_CLASS_NAME;
-}
-
-static int memory_uevent(struct kset *kset, struct kobject *obj,
-			struct kobj_uevent_env *env)
-{
-	int retval = 0;
-
-	return retval;
-}
-
-static const struct kset_uevent_ops memory_uevent_ops = {
-	.name		= memory_uevent_name,
-	.uevent		= memory_uevent,
+	.dev_name = MEMORY_CLASS_NAME,
 };
 
 static BLOCKING_NOTIFIER_HEAD(memory_chain);
···
 {
 	int error;
 
-	memory->sysdev.cls = &memory_sysdev_class;
-	memory->sysdev.id = memory->start_section_nr / sections_per_block;
+	memory->dev.bus = &memory_subsys;
+	memory->dev.id = memory->start_section_nr / sections_per_block;
 
-	error = sysdev_register(&memory->sysdev);
+	error = device_register(&memory->dev);
 	return error;
 }
 
 static void
 unregister_memory(struct memory_block *memory)
 {
-	BUG_ON(memory->sysdev.cls != &memory_sysdev_class);
+	BUG_ON(memory->dev.bus != &memory_subsys);
 
 	/* drop the ref. we got in remove_memory_block() */
-	kobject_put(&memory->sysdev.kobj);
-	sysdev_unregister(&memory->sysdev);
+	kobject_put(&memory->dev.kobj);
+	device_unregister(&memory->dev);
 }
 
 unsigned long __weak memory_block_size_bytes(void)
···
  * uses.
  */
 
-static ssize_t show_mem_start_phys_index(struct sys_device *dev,
-			struct sysdev_attribute *attr, char *buf)
+static ssize_t show_mem_start_phys_index(struct device *dev,
+			struct device_attribute *attr, char *buf)
 {
 	struct memory_block *mem =
-		container_of(dev, struct memory_block, sysdev);
+		container_of(dev, struct memory_block, dev);
 	unsigned long phys_index;
 
 	phys_index = mem->start_section_nr / sections_per_block;
 	return sprintf(buf, "%08lx\n", phys_index);
 }
 
-static ssize_t show_mem_end_phys_index(struct sys_device *dev,
-			struct sysdev_attribute *attr, char *buf)
+static ssize_t show_mem_end_phys_index(struct device *dev,
+			struct device_attribute *attr, char *buf)
 {
 	struct memory_block *mem =
-		container_of(dev, struct memory_block, sysdev);
+		container_of(dev, struct memory_block, dev);
 	unsigned long phys_index;
 
 	phys_index = mem->end_section_nr / sections_per_block;
···
 /*
  * Show whether the section of memory is likely to be hot-removable
  */
-static ssize_t show_mem_removable(struct sys_device *dev,
-			struct sysdev_attribute *attr, char *buf)
+static ssize_t show_mem_removable(struct device *dev,
+			struct device_attribute *attr, char *buf)
 {
 	unsigned long i, pfn;
 	int ret = 1;
 	struct memory_block *mem =
-		container_of(dev, struct memory_block, sysdev);
+		container_of(dev, struct memory_block, dev);
 
 	for (i = 0; i < sections_per_block; i++) {
 		pfn = section_nr_to_pfn(mem->start_section_nr + i);
···
 /*
  * online, offline, going offline, etc.
  */
-static ssize_t show_mem_state(struct sys_device *dev,
-			struct sysdev_attribute *attr, char *buf)
+static ssize_t show_mem_state(struct device *dev,
+			struct device_attribute *attr, char *buf)
 {
 	struct memory_block *mem =
-		container_of(dev, struct memory_block, sysdev);
+		container_of(dev, struct memory_block, dev);
 	ssize_t len = 0;
 
 	/*
···
 }
 
 static ssize_t
-store_mem_state(struct sys_device *dev,
-		struct sysdev_attribute *attr, const char *buf, size_t count)
+store_mem_state(struct device *dev,
+		struct device_attribute *attr, const char *buf, size_t count)
 {
 	struct memory_block *mem;
 	int ret = -EINVAL;
 
-	mem = container_of(dev, struct memory_block, sysdev);
+	mem = container_of(dev, struct memory_block, dev);
 
 	if (!strncmp(buf, "online", min((int)count, 6)))
 		ret = memory_block_change_state(mem, MEM_ONLINE, MEM_OFFLINE);
···
  * s.t. if I offline all of these sections I can then
  * remove the physical device?
  */
-static ssize_t show_phys_device(struct sys_device *dev,
-				struct sysdev_attribute *attr, char *buf)
+static ssize_t show_phys_device(struct device *dev,
+				struct device_attribute *attr, char *buf)
 {
 	struct memory_block *mem =
-		container_of(dev, struct memory_block, sysdev);
+		container_of(dev, struct memory_block, dev);
 	return sprintf(buf, "%d\n", mem->phys_device);
 }
 
-static SYSDEV_ATTR(phys_index, 0444, show_mem_start_phys_index, NULL);
-static SYSDEV_ATTR(end_phys_index, 0444, show_mem_end_phys_index, NULL);
-static SYSDEV_ATTR(state, 0644, show_mem_state, store_mem_state);
-static SYSDEV_ATTR(phys_device, 0444, show_phys_device, NULL);
-static SYSDEV_ATTR(removable, 0444, show_mem_removable, NULL);
+static DEVICE_ATTR(phys_index, 0444, show_mem_start_phys_index, NULL);
+static DEVICE_ATTR(end_phys_index, 0444, show_mem_end_phys_index, NULL);
+static DEVICE_ATTR(state, 0644, show_mem_state, store_mem_state);
+static DEVICE_ATTR(phys_device, 0444, show_phys_device, NULL);
+static DEVICE_ATTR(removable, 0444, show_mem_removable, NULL);
 
 #define mem_create_simple_file(mem, attr_name)	\
-	sysdev_create_file(&mem->sysdev, &attr_##attr_name)
+	device_create_file(&mem->dev, &dev_attr_##attr_name)
 #define mem_remove_simple_file(mem, attr_name)	\
-	sysdev_remove_file(&mem->sysdev, &attr_##attr_name)
+	device_remove_file(&mem->dev, &dev_attr_##attr_name)
 
 /*
  * Block size attribute stuff
  */
 static ssize_t
-print_block_size(struct sysdev_class *class, struct sysdev_class_attribute *attr,
+print_block_size(struct device *dev, struct device_attribute *attr,
 		 char *buf)
 {
 	return sprintf(buf, "%lx\n", get_memory_block_size());
 }
 
-static SYSDEV_CLASS_ATTR(block_size_bytes, 0444, print_block_size, NULL);
+static DEVICE_ATTR(block_size_bytes, 0444, print_block_size, NULL);
 
 static int block_size_init(void)
 {
-	return sysfs_create_file(&memory_sysdev_class.kset.kobj,
-				&attr_block_size_bytes.attr);
+	return device_create_file(memory_subsys.dev_root,
+				  &dev_attr_block_size_bytes);
 }
 
 /*
···
  */
 #ifdef CONFIG_ARCH_MEMORY_PROBE
 static ssize_t
-memory_probe_store(struct class *class, struct class_attribute *attr,
+memory_probe_store(struct device *dev, struct device_attribute *attr,
 		   const char *buf, size_t count)
 {
 	u64 phys_addr;
···
 out:
 	return ret;
 }
-static CLASS_ATTR(probe, S_IWUSR, NULL, memory_probe_store);
+static DEVICE_ATTR(probe, S_IWUSR, NULL, memory_probe_store);
 
 static int memory_probe_init(void)
 {
-	return sysfs_create_file(&memory_sysdev_class.kset.kobj,
-				&class_attr_probe.attr);
+	return device_create_file(memory_subsys.dev_root, &dev_attr_probe);
 }
 #else
 static inline int memory_probe_init(void)
···
 
 /* Soft offline a page */
 static ssize_t
-store_soft_offline_page(struct class *class,
-			struct class_attribute *attr,
+store_soft_offline_page(struct device *dev,
+			struct device_attribute *attr,
 			const char *buf, size_t count)
 {
 	int ret;
···
 
 /* Forcibly offline a page, including killing processes. */
 static ssize_t
-store_hard_offline_page(struct class *class,
-			struct class_attribute *attr,
+store_hard_offline_page(struct device *dev,
+			struct device_attribute *attr,
 			const char *buf, size_t count)
 {
 	int ret;
···
 	return ret ? ret : count;
 }
 
-static CLASS_ATTR(soft_offline_page, 0644, NULL, store_soft_offline_page);
-static CLASS_ATTR(hard_offline_page, 0644, NULL, store_hard_offline_page);
+static DEVICE_ATTR(soft_offline_page, 0644, NULL, store_soft_offline_page);
+static DEVICE_ATTR(hard_offline_page, 0644, NULL, store_hard_offline_page);
 
 static __init int memory_fail_init(void)
 {
 	int err;
 
-	err = sysfs_create_file(&memory_sysdev_class.kset.kobj,
-				&class_attr_soft_offline_page.attr);
+	err = device_create_file(memory_subsys.dev_root,
+				&dev_attr_soft_offline_page);
 	if (!err)
-		err = sysfs_create_file(&memory_sysdev_class.kset.kobj,
-				&class_attr_hard_offline_page.attr);
+		err = device_create_file(memory_subsys.dev_root,
+				&dev_attr_hard_offline_page);
 	return err;
 }
 #else
···
 	return 0;
 }
 
+/*
+ * A reference for the returned object is held and the reference for the
+ * hinted object is released.
+ */
 struct memory_block *find_memory_block_hinted(struct mem_section *section,
 					      struct memory_block *hint)
 {
-	struct kobject *kobj;
-	struct sys_device *sysdev;
-	struct memory_block *mem;
-	char name[sizeof(MEMORY_CLASS_NAME) + 9 + 1];
 	int block_id = base_memory_block_id(__section_nr(section));
+	struct device *hintdev = hint ? &hint->dev : NULL;
+	struct device *dev;
 
-	kobj = hint ? &hint->sysdev.kobj : NULL;
-
-	/*
-	 * This only works because we know that section == sysdev->id
-	 * slightly redundant with sysdev_register()
-	 */
-	sprintf(&name[0], "%s%d", MEMORY_CLASS_NAME, block_id);
-
-	kobj = kset_find_obj_hinted(&memory_sysdev_class.kset, name, kobj);
-	if (!kobj)
+	dev = subsys_find_device_by_id(&memory_subsys, block_id, hintdev);
+	if (hint)
+		put_device(&hint->dev);
+	if (!dev)
 		return NULL;
-
-	sysdev = container_of(kobj, struct sys_device, kobj);
-	mem = container_of(sysdev, struct memory_block, sysdev);
-
-	return mem;
+	return container_of(dev, struct memory_block, dev);
 }
 
 /*
···
  * this gets to be a real problem, we can always use a radix
  * tree or something here.
  *
- * This could be made generic for all sysdev classes.
+ * This could be made generic for all device subsystems.
  */
 struct memory_block *find_memory_block(struct mem_section *section)
 {
···
 	mem = find_memory_block(section);
 	if (mem) {
 		mem->section_count++;
-		kobject_put(&mem->sysdev.kobj);
+		kobject_put(&mem->dev.kobj);
 	} else
 		ret = init_memory_block(&mem, section, state);
 
···
 		unregister_memory(mem);
 		kfree(mem);
 	} else
-		kobject_put(&mem->sysdev.kobj);
+		kobject_put(&mem->dev.kobj);
 
 	mutex_unlock(&mem_sysfs_mutex);
 	return 0;
···
 	int err;
 	unsigned long block_sz;
 
-	memory_sysdev_class.kset.uevent_ops = &memory_uevent_ops;
-	ret = sysdev_class_register(&memory_sysdev_class);
+	ret = subsys_system_register(&memory_subsys, NULL);
 	if (ret)
 		goto out;
 

drivers/base/node.c

···
 /*
- * drivers/base/node.c - basic Node class support
+ * Basic Node interface support
  */
 
-#include <linux/sysdev.h>
 #include <linux/module.h>
 #include <linux/init.h>
 #include <linux/mm.h>
···
 #include <linux/swap.h>
 #include <linux/slab.h>
 
-static struct sysdev_class_attribute *node_state_attrs[];
-
-static struct sysdev_class node_class = {
+static struct bus_type node_subsys = {
 	.name = "node",
-	.attrs = node_state_attrs,
+	.dev_name = "node",
 };
 
 
-static ssize_t node_read_cpumap(struct sys_device *dev, int type, char *buf)
+static ssize_t node_read_cpumap(struct device *dev, int type, char *buf)
 {
 	struct node *node_dev = to_node(dev);
-	const struct cpumask *mask = cpumask_of_node(node_dev->sysdev.id);
+	const struct cpumask *mask = cpumask_of_node(node_dev->dev.id);
 	int len;
 
 	/* 2008/04/07: buf currently PAGE_SIZE, need 9 chars per 32 bits. */
···
 	return len;
 }
 
-static inline ssize_t node_read_cpumask(struct sys_device *dev,
-				struct sysdev_attribute *attr, char *buf)
+static inline ssize_t node_read_cpumask(struct device *dev,
+				struct device_attribute *attr, char *buf)
 {
 	return node_read_cpumap(dev, 0, buf);
 }
-static inline ssize_t node_read_cpulist(struct sys_device *dev,
-				struct sysdev_attribute *attr, char *buf)
+static inline ssize_t node_read_cpulist(struct device *dev,
+				struct device_attribute *attr, char *buf)
 {
 	return node_read_cpumap(dev, 1, buf);
 }
 
-static SYSDEV_ATTR(cpumap,  S_IRUGO, node_read_cpumask, NULL);
-static SYSDEV_ATTR(cpulist, S_IRUGO, node_read_cpulist, NULL);
+static DEVICE_ATTR(cpumap,  S_IRUGO, node_read_cpumask, NULL);
+static DEVICE_ATTR(cpulist, S_IRUGO, node_read_cpulist, NULL);
 
 #define K(x) ((x) << (PAGE_SHIFT - 10))
-static ssize_t node_read_meminfo(struct sys_device * dev,
-			struct sysdev_attribute *attr, char * buf)
+static ssize_t node_read_meminfo(struct device *dev,
+			struct device_attribute *attr, char *buf)
 {
 	int n;
 	int nid = dev->id;
···
 }
 
 #undef K
-static SYSDEV_ATTR(meminfo, S_IRUGO, node_read_meminfo, NULL);
+static DEVICE_ATTR(meminfo, S_IRUGO, node_read_meminfo, NULL);
 
-static ssize_t node_read_numastat(struct sys_device * dev,
-				struct sysdev_attribute *attr, char * buf)
+static ssize_t node_read_numastat(struct device *dev,
+				struct device_attribute *attr, char *buf)
 {
 	return sprintf(buf,
 		       "numa_hit %lu\n"
···
 		       node_page_state(dev->id, NUMA_LOCAL),
 		       node_page_state(dev->id, NUMA_OTHER));
 }
-static SYSDEV_ATTR(numastat, S_IRUGO, node_read_numastat, NULL);
+static DEVICE_ATTR(numastat, S_IRUGO, node_read_numastat, NULL);
 
-static ssize_t node_read_vmstat(struct sys_device *dev,
-				struct sysdev_attribute *attr, char *buf)
+static ssize_t node_read_vmstat(struct device *dev,
+				struct device_attribute *attr, char *buf)
 {
 	int nid = dev->id;
 	int i;
···
 
 	return n;
 }
-static SYSDEV_ATTR(vmstat, S_IRUGO, node_read_vmstat, NULL);
+static DEVICE_ATTR(vmstat, S_IRUGO, node_read_vmstat, NULL);
 
-static ssize_t node_read_distance(struct sys_device * dev,
-			struct sysdev_attribute *attr, char * buf)
+static ssize_t node_read_distance(struct device *dev,
+			struct device_attribute *attr, char * buf)
 {
 	int nid = dev->id;
 	int len = 0;
···
 	len += sprintf(buf + len, "\n");
 	return len;
 }
-static SYSDEV_ATTR(distance, S_IRUGO, node_read_distance, NULL);
+static DEVICE_ATTR(distance, S_IRUGO, node_read_distance, NULL);
 
 #ifdef CONFIG_HUGETLBFS
 /*
···
 static inline bool hugetlb_register_node(struct node *node)
 {
 	if (__hugetlb_register_node &&
-			node_state(node->sysdev.id, N_HIGH_MEMORY)) {
+			node_state(node->dev.id, N_HIGH_MEMORY)) {
 		__hugetlb_register_node(node);
 		return true;
 	}
···
 {
 	int error;
 
-	node->sysdev.id = num;
-	node->sysdev.cls = &node_class;
-	error = sysdev_register(&node->sysdev);
+	node->dev.id = num;
+	node->dev.bus = &node_subsys;
+	error = device_register(&node->dev);
 
 	if (!error){
-		sysdev_create_file(&node->sysdev, &attr_cpumap);
-		sysdev_create_file(&node->sysdev, &attr_cpulist);
-		sysdev_create_file(&node->sysdev, &attr_meminfo);
-		sysdev_create_file(&node->sysdev, &attr_numastat);
-		sysdev_create_file(&node->sysdev, &attr_distance);
-		sysdev_create_file(&node->sysdev, &attr_vmstat);
+		device_create_file(&node->dev, &dev_attr_cpumap);
+		device_create_file(&node->dev, &dev_attr_cpulist);
+		device_create_file(&node->dev, &dev_attr_meminfo);
+		device_create_file(&node->dev, &dev_attr_numastat);
+		device_create_file(&node->dev, &dev_attr_distance);
+		device_create_file(&node->dev, &dev_attr_vmstat);
 
 		scan_unevictable_register_node(node);
 
···
  */
 void unregister_node(struct node *node)
 {
-	sysdev_remove_file(&node->sysdev, &attr_cpumap);
-	sysdev_remove_file(&node->sysdev, &attr_cpulist);
-	sysdev_remove_file(&node->sysdev, &attr_meminfo);
-	sysdev_remove_file(&node->sysdev, &attr_numastat);
-	sysdev_remove_file(&node->sysdev, &attr_distance);
-	sysdev_remove_file(&node->sysdev, &attr_vmstat);
+	device_remove_file(&node->dev, &dev_attr_cpumap);
+	device_remove_file(&node->dev, &dev_attr_cpulist);
+	device_remove_file(&node->dev, &dev_attr_meminfo);
+	device_remove_file(&node->dev, &dev_attr_numastat);
+	device_remove_file(&node->dev, &dev_attr_distance);
+	device_remove_file(&node->dev, &dev_attr_vmstat);
 
 	scan_unevictable_unregister_node(node);
 	hugetlb_unregister_node(node);		/* no-op, if memoryless node */
 
-	sysdev_unregister(&node->sysdev);
+	device_unregister(&node->dev);
 }
 
 struct node node_devices[MAX_NUMNODES];
···
 	if (!obj)
 		return 0;
 
-	ret = sysfs_create_link(&node_devices[nid].sysdev.kobj,
+	ret = sysfs_create_link(&node_devices[nid].dev.kobj,
 				&obj->kobj,
 				kobject_name(&obj->kobj));
 	if (ret)
 		return ret;
 
 	return sysfs_create_link(&obj->kobj,
-				 &node_devices[nid].sysdev.kobj,
-				 kobject_name(&node_devices[nid].sysdev.kobj));
+				 &node_devices[nid].dev.kobj,
+				 kobject_name(&node_devices[nid].dev.kobj));
 }
 
 int unregister_cpu_under_node(unsigned int cpu, unsigned int nid)
···
 	if (!obj)
 		return 0;
 
-	sysfs_remove_link(&node_devices[nid].sysdev.kobj,
+	sysfs_remove_link(&node_devices[nid].dev.kobj,
 			  kobject_name(&obj->kobj));
 	sysfs_remove_link(&obj->kobj,
-			  kobject_name(&node_devices[nid].sysdev.kobj));
+			  kobject_name(&node_devices[nid].dev.kobj));
 
 	return 0;
 }
···
 			continue;
 		if (page_nid != nid)
 			continue;
-		ret = sysfs_create_link_nowarn(&node_devices[nid].sysdev.kobj,
-					&mem_blk->sysdev.kobj,
-					kobject_name(&mem_blk->sysdev.kobj));
+		ret = sysfs_create_link_nowarn(&node_devices[nid].dev.kobj,
+					&mem_blk->dev.kobj,
+					kobject_name(&mem_blk->dev.kobj));
 		if (ret)
 			return ret;
 
-		return sysfs_create_link_nowarn(&mem_blk->sysdev.kobj,
-				&node_devices[nid].sysdev.kobj,
-				kobject_name(&node_devices[nid].sysdev.kobj));
+		return sysfs_create_link_nowarn(&mem_blk->dev.kobj,
+				&node_devices[nid].dev.kobj,
+				kobject_name(&node_devices[nid].dev.kobj));
 	}
 	/* mem section does not span the specified node */
 	return 0;
···
 			continue;
 		if (node_test_and_set(nid, *unlinked_nodes))
 			continue;
-		sysfs_remove_link(&node_devices[nid].sysdev.kobj,
-			 kobject_name(&mem_blk->sysdev.kobj));
-		sysfs_remove_link(&mem_blk->sysdev.kobj,
-			 kobject_name(&node_devices[nid].sysdev.kobj));
+		sysfs_remove_link(&node_devices[nid].dev.kobj,
+			 kobject_name(&mem_blk->dev.kobj));
+		sysfs_remove_link(&mem_blk->dev.kobj,
+			 kobject_name(&node_devices[nid].dev.kobj));
 	}
 	NODEMASK_FREE(unlinked_nodes);
 	return 0;
···
 	}
 
 	if (mem_blk)
-		kobject_put(&mem_blk->sysdev.kobj);
+		kobject_put(&mem_blk->dev.kobj);
 	return err;
 }
 
···
 }
 
 struct node_attr {
-	struct sysdev_class_attribute attr;
+	struct device_attribute attr;
 	enum node_states state;
 };
 
-static ssize_t show_node_state(struct sysdev_class *class,
-			       struct sysdev_class_attribute *attr, char *buf)
+static ssize_t show_node_state(struct device *dev,
+			       struct device_attribute *attr, char *buf)
 {
 	struct node_attr *na = container_of(attr, struct node_attr, attr);
 	return print_nodes_state(na->state, buf);
 }
 
 #define _NODE_ATTR(name, state) \
-	{ _SYSDEV_CLASS_ATTR(name, 0444, show_node_state, NULL), state }
+	{ __ATTR(name, 0444, show_node_state, NULL), state }
 
 static struct node_attr node_state_attr[] = {
 	_NODE_ATTR(possible, N_POSSIBLE),
···
 #endif
 };
 
-static struct sysdev_class_attribute *node_state_attrs[] = {
-	&node_state_attr[0].attr,
-	&node_state_attr[1].attr,
-	&node_state_attr[2].attr,
-	&node_state_attr[3].attr,
+static struct attribute *node_state_attrs[] = {
+	&node_state_attr[0].attr.attr,
+	&node_state_attr[1].attr.attr,
+	&node_state_attr[2].attr.attr,
+	&node_state_attr[3].attr.attr,
 #ifdef CONFIG_HIGHMEM
-	&node_state_attr[4].attr,
+	&node_state_attr[4].attr.attr,
 #endif
 	NULL
+};
+
+static struct attribute_group memory_root_attr_group = {
+	.attrs = node_state_attrs,
+};
+
+static const struct attribute_group *cpu_root_attr_groups[] = {
+	&memory_root_attr_group,
+	NULL,
 };
 
 #define NODE_CALLBACK_PRI	2	/* lower than SLAB */
···
  	BUILD_BUG_ON(ARRAY_SIZE(node_state_attr) != NR_NODE_STATES);
  	BUILD_BUG_ON(ARRAY_SIZE(node_state_attrs)-1 != NR_NODE_STATES);
 
-	ret = sysdev_class_register(&node_class);
+	ret = subsys_system_register(&node_subsys, cpu_root_attr_groups);
 	if (!ret) {
 		hotplug_memory_notifier(node_memory_callback,
 					NODE_CALLBACK_PRI);

include/linux/memory.h

···
 #ifndef _LINUX_MEMORY_H_
 #define _LINUX_MEMORY_H_
 
-#include <linux/sysdev.h>
 #include <linux/node.h>
 #include <linux/compiler.h>
 #include <linux/mutex.h>
···
 	int phys_device;		/* to which fru does this belong? */
 	void *hw;			/* optional pointer to fw/hw data */
 	int (*phys_callback)(struct memory_block *);
-	struct sys_device sysdev;
+	struct device dev;
 };
 
 int arch_get_memory_phys_device(unsigned long start_pfn);

include/linux/node.h

···
 #ifndef _LINUX_NODE_H_
 #define _LINUX_NODE_H_
 
-#include <linux/sysdev.h>
+#include <linux/device.h>
 #include <linux/cpumask.h>
 #include <linux/workqueue.h>
 
 struct node {
-	struct sys_device	sysdev;
+	struct device	dev;
 
 #if defined(CONFIG_MEMORY_HOTPLUG_SPARSE) && defined(CONFIG_HUGETLBFS)
 	struct work_struct	node_work;
···
 }
 #endif
 
-#define to_node(sys_device) container_of(sys_device, struct node, sysdev)
+#define to_node(device) container_of(device, struct node, dev)
 
 #endif /* _LINUX_NODE_H_ */

mm/compaction.c

···
 }
 
 #if defined(CONFIG_SYSFS) && defined(CONFIG_NUMA)
-ssize_t sysfs_compact_node(struct sys_device *dev,
-			struct sysdev_attribute *attr,
+ssize_t sysfs_compact_node(struct device *dev,
+			struct device_attribute *attr,
 			const char *buf, size_t count)
 {
 	compact_node(dev->id);
 
 	return count;
 }
-static SYSDEV_ATTR(compact, S_IWUSR, NULL, sysfs_compact_node);
+static DEVICE_ATTR(compact, S_IWUSR, NULL, sysfs_compact_node);
 
 int compaction_register_node(struct node *node)
 {
-	return sysdev_create_file(&node->sysdev, &attr_compact);
+	return device_create_file(&node->dev, &dev_attr_compact);
 }
 
 void compaction_unregister_node(struct node *node)
 {
-	return sysdev_remove_file(&node->sysdev, &attr_compact);
+	return device_remove_file(&node->dev, &dev_attr_compact);
 }
 #endif /* CONFIG_SYSFS && CONFIG_NUMA */

mm/hugetlb.c

···
 
 /*
  * node_hstate/s - associate per node hstate attributes, via their kobjects,
- * with node sysdevs in node_devices[] using a parallel array.  The array
- * index of a node sysdev or _hstate == node id.
- * This is here to avoid any static dependency of the node sysdev driver, in
+ * with node devices in node_devices[] using a parallel array.  The array
+ * index of a node device or _hstate == node id.
+ * This is here to avoid any static dependency of the node device driver, in
  * the base kernel, on the hugetlb module.
  */
 struct node_hstate {
···
 struct node_hstate node_hstates[MAX_NUMNODES];
 
 /*
- * A subset of global hstate attributes for node sysdevs
+ * A subset of global hstate attributes for node devices
  */
 static struct attribute *per_node_hstate_attrs[] = {
 	&nr_hugepages_attr.attr,
···
 };
 
 /*
- * kobj_to_node_hstate - lookup global hstate for node sysdev hstate attr kobj.
+ * kobj_to_node_hstate - lookup global hstate for node device hstate attr kobj.
  * Returns node id via non-NULL nidp.
  */
 static struct hstate *kobj_to_node_hstate(struct kobject *kobj, int *nidp)
···
 }
 
 /*
- * Unregister hstate attributes from a single node sysdev.
+ * Unregister hstate attributes from a single node device.
  * No-op if no hstate attributes attached.
  */
 void hugetlb_unregister_node(struct node *node)
 {
 	struct hstate *h;
-	struct node_hstate *nhs = &node_hstates[node->sysdev.id];
+	struct node_hstate *nhs = &node_hstates[node->dev.id];
 
 	if (!nhs->hugepages_kobj)
 		return;		/* no hstate attributes */
···
 }
 
 /*
- * hugetlb module exit:  unregister hstate attributes from node sysdevs
+ * hugetlb module exit:  unregister hstate attributes from node devices
  * that have them.
  */
 static void hugetlb_unregister_all_nodes(void)
···
 	int nid;
 
 	/*
-	 * disable node sysdev registrations.
+	 * disable node device registrations.
 	 */
 	register_hugetlbfs_with_node(NULL, NULL);
 
···
 }
 
 /*
- * Register hstate attributes for a single node sysdev.
+ * Register hstate attributes for a single node device.
  * No-op if attributes already registered.
  */
 void hugetlb_register_node(struct node *node)
 {
 	struct hstate *h;
-	struct node_hstate *nhs = &node_hstates[node->sysdev.id];
+	struct node_hstate *nhs = &node_hstates[node->dev.id];
 	int err;
 
 	if (nhs->hugepages_kobj)
 		return;		/* already allocated */
 
 	nhs->hugepages_kobj = kobject_create_and_add("hugepages",
-							&node->sysdev.kobj);
+							&node->dev.kobj);
 	if (!nhs->hugepages_kobj)
 		return;
 
···
 		if (err) {
 			printk(KERN_ERR "Hugetlb: Unable to add hstate %s"
 					" for node %d\n",
-						h->name, node->sysdev.id);
+						h->name, node->dev.id);
 			hugetlb_unregister_node(node);
 			break;
 		}
···
 
 /*
  * hugetlb init time:  register hstate attributes for all registered node
- * sysdevs of nodes that have memory.  All on-line nodes should have
- * registered their associated sysdev by this time.
+ * devices of nodes that have memory.  All on-line nodes should have
+ * registered their associated device by this time.
  */
 static void hugetlb_register_all_nodes(void)
 {
···
 
 	for_each_node_state(nid, N_HIGH_MEMORY) {
 		struct node *node = &node_devices[nid];
-		if (node->sysdev.id == nid)
+		if (node->dev.id == nid)
 			hugetlb_register_node(node);
 	}
 
 	/*
-	 * Let the node sysdev driver know we're here so it can
+	 * Let the node device driver know we're here so it can
 	 * [un]register hstate attributes on node hotplug.
 	 */
 	register_hugetlbfs_with_node(hugetlb_register_node,

mm/vmscan.c

···
  * a specified node's per zone unevictable lists for evictable pages.
  */
 
-static ssize_t read_scan_unevictable_node(struct sys_device *dev,
-					  struct sysdev_attribute *attr,
+static ssize_t read_scan_unevictable_node(struct device *dev,
+					  struct device_attribute *attr,
 					  char *buf)
 {
 	warn_scan_unevictable_pages();
 	return sprintf(buf, "0\n");	/* always zero; should fit... */
 }
 
-static ssize_t write_scan_unevictable_node(struct sys_device *dev,
-					   struct sysdev_attribute *attr,
+static ssize_t write_scan_unevictable_node(struct device *dev,
+					   struct device_attribute *attr,
 					const char *buf, size_t count)
 {
 	warn_scan_unevictable_pages();
···
 }
 
 
-static SYSDEV_ATTR(scan_unevictable_pages, S_IRUGO | S_IWUSR,
+static DEVICE_ATTR(scan_unevictable_pages, S_IRUGO | S_IWUSR,
 			read_scan_unevictable_node,
 			write_scan_unevictable_node);
 
 int scan_unevictable_register_node(struct node *node)
 {
-	return sysdev_create_file(&node->sysdev, &attr_scan_unevictable_pages);
+	return device_create_file(&node->dev, &dev_attr_scan_unevictable_pages);
 }
 
 void scan_unevictable_unregister_node(struct node *node)
 {
-	sysdev_remove_file(&node->sysdev, &attr_scan_unevictable_pages);
+	device_remove_file(&node->dev, &dev_attr_scan_unevictable_pages);
 }
 #endif