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 <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/base/memory.c b/drivers/base/memory.c
index 8272d92..f17e3ea 100644
--- a/drivers/base/memory.c
+++ b/drivers/base/memory.c
@@ -1,5 +1,5 @@
 /*
- * drivers/base/memory.c - basic Memory class support
+ * Memory subsystem support
  *
  * Written by Matt Tolentino <matthew.e.tolentino@intel.com>
  *            Dave Hansen <haveblue@us.ibm.com>
@@ -10,7 +10,6 @@
  * 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>
@@ -38,26 +37,9 @@
 	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);
@@ -96,21 +78,21 @@
 {
 	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)
@@ -138,22 +120,22 @@
  * 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;
@@ -163,13 +145,13 @@
 /*
  * 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);
@@ -182,11 +164,11 @@
 /*
  * 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;
 
 	/*
@@ -324,13 +306,13 @@
 }
 
 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);
@@ -351,41 +333,41 @@
  * 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);
 }
 
 /*
@@ -396,7 +378,7 @@
  */
 #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;
@@ -423,12 +405,11 @@
 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)
@@ -444,8 +425,8 @@
 
 /* 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;
@@ -463,8 +444,8 @@
 
 /* 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;
@@ -478,18 +459,18 @@
 	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
@@ -509,31 +490,23 @@
 	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);
 }
 
 /*
@@ -542,7 +515,7 @@
  * 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)
 {
@@ -598,7 +571,7 @@
 	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);
 
@@ -631,7 +604,7 @@
 		unregister_memory(mem);
 		kfree(mem);
 	} else
-		kobject_put(&mem->sysdev.kobj);
+		kobject_put(&mem->dev.kobj);
 
 	mutex_unlock(&mem_sysfs_mutex);
 	return 0;
@@ -664,8 +637,7 @@
 	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;