Merge samba.org:/scratch/anton/linux-2.5

into samba.org:/scratch/anton/sfr

drivers/base/base.h

 #undef DEBUG
 
 extern struct semaphore device_sem;
+extern struct semaphore devclass_sem;
 
 extern int bus_add_device(struct device * dev);
 extern void bus_remove_device(struct device * dev);

drivers/base/class.c

@@ -13,6 +13,8 @@
 #define to_class_attr(_attr) container_of(_attr,struct devclass_attribute,attr)
 #define to_class(obj) container_of(obj,struct device_class,subsys.kset.kobj)
 
+DECLARE_MUTEX(devclass_sem);
+
 static ssize_t
 devclass_attr_show(struct kobject * kobj, struct attribute * attr, char * buf)
 {
@@ -163,29 +165,34 @@ int devclass_add_device(struct device * dev)
 	struct device_class * cls;
 	int error = 0;
 
+	down(&devclass_sem);
 	if (dev->driver) {
 		cls = get_devclass(dev->driver->devclass);
-		if (cls) {
-			down_write(&cls->subsys.rwsem);
+
+		if (!cls)
+			goto Done;
+
 		pr_debug("device class %s: adding device %s\n",
 			 cls->name,dev->name);
 		if (cls->add_device) 
 			error = cls->add_device(dev);
-			if (!error) {
-				enum_device(cls,dev);
-				interface_add_dev(dev);
+		if (error) {
+			put_devclass(cls);
+			goto Done;
 		}
 
+		down_write(&cls->subsys.rwsem);
+		enum_device(cls,dev);
 		list_add_tail(&dev->class_list,&cls->devices.list);
-
 		/* notify userspace (call /sbin/hotplug) */
 		class_hotplug (dev, "add");
 
 		up_write(&cls->subsys.rwsem);
-			if (error)
-				put_devclass(cls);
-		}
+
+		interface_add_dev(dev);
 	}
+ Done:
+	up(&devclass_sem);
 	return error;
 }
 
@@ -193,13 +200,18 @@ void devclass_remove_device(struct device * dev)
 {
 	struct device_class * cls;
 
+	down(&devclass_sem);
 	if (dev->driver) {
 		cls = dev->driver->devclass;
-		if (cls) {
+		if (!cls) 
+			goto Done;
+
+		interface_remove_dev(dev);
+
 		down_write(&cls->subsys.rwsem);
 		pr_debug("device class %s: removing device %s\n",
 			 cls->name,dev->name);
-			interface_remove_dev(dev);
+
 		unenum_device(cls,dev);
 
 		list_del(&dev->class_list);
@@ -207,12 +219,14 @@ void devclass_remove_device(struct device * dev)
 		/* notify userspace (call /sbin/hotplug) */
 		class_hotplug (dev, "remove");
 
+		up_write(&cls->subsys.rwsem);
+
 		if (cls->remove_device)
 			cls->remove_device(dev);
-			up_write(&cls->subsys.rwsem);
 		put_devclass(cls);
 	}
-	}
+ Done:
+	up(&devclass_sem);
 }
 
 struct device_class * get_devclass(struct device_class * cls)

drivers/base/core.c

@@ -143,7 +143,6 @@ void device_initialize(struct device *dev)
 	INIT_LIST_HEAD(&dev->driver_list);
 	INIT_LIST_HEAD(&dev->bus_list);
 	INIT_LIST_HEAD(&dev->class_list);
-	INIT_LIST_HEAD(&dev->intf_list);
 }
 
 /**

drivers/base/intf.c

@@ -12,80 +12,31 @@
 
 #define to_intf(node) container_of(node,struct device_interface,kset.kobj.entry)
 
-#define to_data(e) container_of(e,struct intf_data,kobj.entry)
+#define to_dev(d) container_of(d,struct device,class_list)
 
 /**
  *	intf_dev_link - create sysfs symlink for interface.
- *	@data:	interface data descriptor.
+ *	@intf:	interface.
+ *	@dev:	device.
  *
  *	Create a symlink 'phys' in the interface's directory to 
  */
 
-static int intf_dev_link(struct intf_data * data)
+static int intf_dev_link(struct device_interface * intf, struct device * dev)
 {
-	char	name[16];
-	snprintf(name,16,"%d",data->intf_num);
-	return sysfs_create_link(&data->intf->kset.kobj,&data->dev->kobj,name);
+	return sysfs_create_link(&intf->kset.kobj,&dev->kobj,dev->bus_id);
 }
 
 /**
  *	intf_dev_unlink - remove symlink for interface.
- *	@intf:	interface data descriptor.
- *
- */
-
-static void intf_dev_unlink(struct intf_data * data)
-{
-	char	name[16];
-	snprintf(name,16,"%d",data->intf_num);
-	sysfs_remove_link(&data->intf->kset.kobj,name);
-}
-
-
-/**
- *	interface_add_data - attach data descriptor
- *	@data:	interface data descriptor.
- *
- *	This attaches the per-instance interface object to the
- *	interface (by registering its kobject) and the device
- *	itself (by inserting it into the device's list).
- *
- *	Note that there is no explicit protection done in this
- *	function. This should be called from the interface's 
- *	add_device() method, which is called under the protection
- *	of the class's rwsem.
- */
-
-int interface_add_data(struct intf_data * data)
-{
-	struct device_interface * intf = data->intf;
-
-	if (intf) {
-		data->intf_num = intf->devnum++;
-		data->kobj.kset = &intf->kset;
-		kobject_register(&data->kobj);
-
-		list_add_tail(&data->dev_entry,&data->dev->intf_list);
-		return intf_dev_link(data);
-	}
-	return -EINVAL;
-}
-
-
-/**
- *	interface_remove_data - detach data descriptor.
- *	@data:	interface data descriptor.
+ *	@intf:	interface.
+ *	@dev:	device.
  *
- *	This detaches the per-instance data descriptor by removing 
- *	it from the device's list and unregistering the kobject from
- *	the subsystem.
  */
 
-void interface_remove_data(struct intf_data * data)
+static void intf_dev_unlink(struct device_interface * intf, struct device * dev)
 {
-	intf_dev_unlink(data);
-	list_del_init(&data->dev_entry);
-	kobject_unregister(&data->kobj);
+	sysfs_remove_link(&intf->kset.kobj,dev->bus_id);
 }
 
 
@@ -103,33 +54,28 @@ static int add(struct device_interface * intf, struct device * dev)
 {
 	int error = 0;
 
-	if (intf->add_device) 
-		error = intf->add_device(dev);
+	if (intf->add_device) {
+		if (!(error = intf->add_device(dev)))
+			intf_dev_link(intf,dev);
+	}
 	pr_debug(" -> %s (%d)\n",dev->bus_id,error);
 	return error;
 }
 
 /**
  *	del - detach device from interface.
- *	@data:	interface data descriptor.
- *
- *	Another simple helper. Remove the data descriptor from 
- *	the device and the interface, then call the interface's 
- *	remove_device() method.
+ *	@intf:	interface.
+ *	@dev:	device.
  */
 
-static void del(struct intf_data * data)
+static void del(struct device_interface * intf, struct device * dev)
 {
-	struct device_interface * intf = data->intf;
-
 	pr_debug(" -> %s ",intf->name);
-	interface_remove_data(data);
 	if (intf->remove_device)
-		intf->remove_device(data);
+		intf->remove_device(dev);
+	intf_dev_unlink(intf,dev);
 }
 
-#define to_dev(entry) container_of(entry,struct device,class_list)
-
 
 /**
  *	add_intf - add class's devices to interface.
@@ -145,10 +91,8 @@ static void add_intf(struct device_interface * intf)
 	struct device_class * cls = intf->devclass;
 	struct list_head * entry;
 
-	down_write(&cls->subsys.rwsem);
 	list_for_each(entry,&cls->devices.list)
 		add(intf,to_dev(entry));
-	up_write(&cls->subsys.rwsem);
 }
 
 /**
@@ -164,6 +108,7 @@ int interface_register(struct device_interface * intf)
 {
 	struct device_class * cls = get_devclass(intf->devclass);
 
+	down(&devclass_sem);
 	if (cls) {
 		pr_debug("register interface '%s' with class '%s'\n",
 			 intf->name,cls->name);
@@ -173,6 +118,7 @@ int interface_register(struct device_interface * intf)
 		kset_register(&intf->kset);
 		add_intf(intf);
 	}
+	up(&devclass_sem);
 	return 0;
 }
 
@@ -188,14 +134,13 @@ int interface_register(struct device_interface * intf)
 
 static void del_intf(struct device_interface * intf)
 {
+	struct device_class * cls = intf->devclass;
 	struct list_head * entry;
 
-	down_write(&intf->devclass->subsys.rwsem);
-	list_for_each(entry,&intf->kset.list) {
-		struct intf_data * data = to_data(entry);
-		del(data);
+	list_for_each(entry,&cls->devices.list) {
+		struct device * dev = to_dev(entry);
+		del(intf,dev);
 	}
-	up_write(&intf->devclass->subsys.rwsem);
 }
 
 /**
@@ -210,6 +155,8 @@ static void del_intf(struct device_interface * intf)
 void interface_unregister(struct device_interface * intf)
 {
 	struct device_class * cls = intf->devclass;
+
+	down(&devclass_sem);
 	if (cls) {
 		pr_debug("unregistering interface '%s' from class '%s'\n",
 			 intf->name,cls->name);
@@ -217,6 +164,7 @@ void interface_unregister(struct device_interface * intf)
 		kset_unregister(&intf->kset);
 		put_devclass(cls);
 	}
+	up(&devclass_sem);
 }
 
 
@@ -255,20 +203,21 @@ int interface_add_dev(struct device * dev)
  *	This is another helper for the class driver core, and called
  *	when the device is being removed from the class. 
  *	
- *	We iterate over the list of interface data descriptors attached
- *	to the device, and call del() [above] for each. Again, the 
- *	class's rwsem is assumed to be held during this.
+ *	We iterate over the list of the class's devices and call del() 
+ *	[above] for each. Again, the class's rwsem is _not_ held, but
+ *	the devclass_sem is (see class.c).
  */
 
 void interface_remove_dev(struct device * dev)
 {
 	struct list_head * entry, * next;
+	struct device_class * cls = dev->driver->devclass;
 
 	pr_debug("interfaces: removing device %s\n",dev->name);
 
-	list_for_each_safe(entry,next,&dev->intf_list) {
-		struct intf_data * intf_data = to_data(entry);
-		del(intf_data);
+	list_for_each_safe(entry,next,&cls->subsys.kset.list) {
+		struct device_interface * intf = to_intf(entry);
+		del(intf,dev);
 	}
 }
 

drivers/char/tty_io.c

@@ -1944,26 +1944,24 @@ static void flush_to_ldisc(void *private_)
 		schedule_delayed_work(&tty->flip.work, 1);
 		return;
 	}
+
+	spin_lock_irqsave(&tty->read_lock, flags);
 	if (tty->flip.buf_num) {
 		cp = tty->flip.char_buf + TTY_FLIPBUF_SIZE;
 		fp = tty->flip.flag_buf + TTY_FLIPBUF_SIZE;
 		tty->flip.buf_num = 0;
-
-		local_irq_save(flags); // FIXME: is this safe?
 		tty->flip.char_buf_ptr = tty->flip.char_buf;
 		tty->flip.flag_buf_ptr = tty->flip.flag_buf;
 	} else {
 		cp = tty->flip.char_buf;
 		fp = tty->flip.flag_buf;
 		tty->flip.buf_num = 1;
-
-		local_irq_save(flags); // FIXME: is this safe?
 		tty->flip.char_buf_ptr = tty->flip.char_buf + TTY_FLIPBUF_SIZE;
 		tty->flip.flag_buf_ptr = tty->flip.flag_buf + TTY_FLIPBUF_SIZE;
 	}
 	count = tty->flip.count;
 	tty->flip.count = 0;
-	local_irq_restore(flags); // FIXME: is this safe?
+	spin_unlock_irqrestore(&tty->read_lock, flags);
 
 	tty->ldisc.receive_buf(tty, cp, fp, count);
 }

fs/sysfs/Makefile

@@ -2,4 +2,4 @@
 # Makefile for the sysfs virtual filesystem
 #
 
-obj-y		:= inode.o
+obj-y		:= inode.o file.o dir.o symlink.o mount.o bin.o

fs/sysfs/bin.c

+/*
+ * bin.c - binary file operations for sysfs.
+ */
+
+#include <linux/fs.h>
+#include <linux/module.h>
+#include <linux/kobject.h>
+
+#include "sysfs.h"
+
+static struct file_operations bin_fops;
+
+static int fill_read(struct file * file, struct sysfs_bin_buffer * buffer)
+{
+	struct bin_attribute * attr = file->f_dentry->d_fsdata;
+	struct kobject * kobj = file->f_dentry->d_parent->d_fsdata;
+
+	if (!buffer->data)
+		attr->read(kobj,buffer);
+	return buffer->size ? 0 : -ENOENT;
+}
+
+static int flush_read(struct file * file, char * userbuf, 
+		      struct sysfs_bin_buffer * buffer)
+{
+	return copy_to_user(userbuf,buffer->data + buffer->offset,buffer->count) ? 
+		-EFAULT : 0;
+}
+
+static ssize_t
+read(struct file * file, char * userbuf, size_t count, loff_t * off)
+{
+	struct sysfs_bin_buffer * buffer = file->private_data;
+	int ret;
+
+	ret = fill_read(file,buffer);
+	if (ret) 
+		goto Done;
+
+	buffer->offset = *off;
+
+	if (count > (buffer->size - *off))
+		count = buffer->size - *off;
+
+	buffer->count = count;
+
+	ret = flush_read(file,userbuf,buffer);
+	if (!ret) {
+		*off += count;
+		ret = count;
+	}
+ Done:
+	return ret;
+}
+
+int alloc_buf_data(struct sysfs_bin_buffer * buffer)
+{
+	buffer->data = kmalloc(buffer->count,GFP_KERNEL);
+	if (buffer->data) {
+		memset(buffer->data,0,buffer->count);
+		return 0;
+	} else
+		return -ENOMEM;
+}
+
+static int fill_write(struct file * file, const char * userbuf, 
+		      struct sysfs_bin_buffer * buffer)
+{
+	return copy_from_user(buffer,userbuf,buffer->count) ?
+		-EFAULT : 0;
+}
+
+static int flush_write(struct file * file, const char * userbuf, 
+		       struct sysfs_bin_buffer * buffer)
+{
+	struct bin_attribute * attr = file->f_dentry->d_fsdata;
+	struct kobject * kobj = file->f_dentry->d_parent->d_fsdata;
+
+	return attr->write(kobj,buffer);
+}
+
+static ssize_t write(struct file * file, const char * userbuf,
+		     size_t count, loff_t * off)
+{
+	struct sysfs_bin_buffer * buffer = file->private_data;
+	int ret;
+
+	if (count > PAGE_SIZE)
+		count = PAGE_SIZE;
+	buffer->count = count;
+
+	ret = alloc_buf_data(buffer);
+	if (ret)
+		goto Done;
+
+	ret = fill_write(file,userbuf,buffer);
+	if (ret)
+		goto Done;
+
+	ret = flush_write(file,userbuf,buffer);
+	if (ret > 0)
+		*off += count;
+ Done:
+	if (buffer->data) {
+		kfree(buffer->data);
+		buffer->data = NULL;
+	}
+	return ret;
+}
+
+static int check_perm(struct inode * inode, struct file * file)
+{
+	struct kobject * kobj = kobject_get(file->f_dentry->d_parent->d_fsdata);
+	struct bin_attribute * attr = file->f_dentry->d_fsdata;
+	struct sysfs_bin_buffer * buffer;
+	int error = 0;
+
+	if (!kobj || !attr)
+		goto Einval;
+
+	/* File needs write support.
+	 * The inode's perms must say it's ok, 
+	 * and we must have a store method.
+	 */
+	if (file->f_mode & FMODE_WRITE) {
+		if (!(inode->i_mode & S_IWUGO) || !attr->write)
+			goto Eaccess;
+	}
+
+	/* File needs read support.
+	 * The inode's perms must say it's ok, and we there
+	 * must be a show method for it.
+	 */
+	if (file->f_mode & FMODE_READ) {
+		if (!(inode->i_mode & S_IRUGO) || !attr->read)
+			goto Eaccess;
+	}
+
+	buffer = kmalloc(sizeof(struct sysfs_bin_buffer),GFP_KERNEL);
+	if (buffer) {
+		memset(buffer,0,sizeof(struct sysfs_bin_buffer));
+		file->private_data = buffer;
+	} else
+		error = -ENOMEM;
+	goto Done;
+
+ Einval:
+	error = -EINVAL;
+	goto Done;
+ Eaccess:
+	error = -EACCES;
+ Done:
+	if (error && kobj)
+		kobject_put(kobj);
+	return error;
+}
+
+static int open(struct inode * inode, struct file * file)
+{
+	return check_perm(inode,file);
+}
+
+static int release(struct inode * inode, struct file * file)
+{
+	struct kobject * kobj = file->f_dentry->d_parent->d_fsdata;
+	u8 * buffer = file->private_data;
+
+	if (kobj) 
+		kobject_put(kobj);
+	if (buffer)
+		kfree(buffer);
+	return 0;
+}
+
+static struct file_operations bin_fops = {
+	.read		= read,
+	.write		= write,
+	.llseek		= generic_file_llseek,
+	.open		= open,
+	.release	= release,
+};
+
+/**
+ *	sysfs_create_bin_file - create binary file for object.
+ *	@kobj:	object.
+ *	@attr:	attribute descriptor.
+ *
+ */
+
+int sysfs_create_bin_file(struct kobject * kobj, struct bin_attribute * attr)
+{
+	struct dentry * dentry;
+	struct dentry * parent;
+	int error = 0;
+
+	if (!kobj || !attr)
+		return -EINVAL;
+
+	parent = kobj->dentry;
+
+	down(&parent->d_inode->i_sem);
+	dentry = sysfs_get_dentry(parent,attr->attr.name);
+	if (!IS_ERR(dentry)) {
+		dentry->d_fsdata = (void *)attr;
+		error = sysfs_create(dentry,
+				     (attr->attr.mode & S_IALLUGO) | S_IFREG,
+				     NULL);
+		if (!error) {
+			dentry->d_inode->i_size = attr->size;
+			dentry->d_inode->i_fop = &bin_fops;
+		}
+	} else
+		error = PTR_ERR(dentry);
+	up(&parent->d_inode->i_sem);
+	return error;
+}
+
+
+/**
+ *	sysfs_remove_bin_file - remove binary file for object.
+ *	@kobj:	object.
+ *	@attr:	attribute descriptor.
+ *
+ */
+
+int sysfs_remove_bin_file(struct kobject * kobj, struct bin_attribute * attr)
+{
+	sysfs_hash_and_remove(kobj->dentry,attr->attr.name);
+}
+
+EXPORT_SYMBOL(sysfs_create_bin_file);
+EXPORT_SYMBOL(sysfs_remove_bin_file);

fs/sysfs/dir.c

+/*
+ * dir.c - Operations for sysfs directories.
+ */
+
+#undef DEBUG
+
+#include <linux/fs.h>
+#include <linux/mount.h>
+#include <linux/module.h>
+#include <linux/kobject.h>
+#include "sysfs.h"
+
+static int init_dir(struct inode * inode)
+{
+	inode->i_op = &simple_dir_inode_operations;
+	inode->i_fop = &simple_dir_operations;
+
+	/* directory inodes start off with i_nlink == 2 (for "." entry) */
+	inode->i_nlink++;
+	return 0;
+}
+
+/**
+ *	sysfs_create_dir - create a directory for an object.
+ *	@parent:	parent parent object.
+ *	@kobj:		object we're creating directory for. 
+ */
+
+int sysfs_create_dir(struct kobject * kobj)
+{
+	struct dentry * dentry = NULL;
+	struct dentry * parent;
+	int error = 0;
+
+	if (!kobj)
+		return -EINVAL;
+
+	if (kobj->parent)
+		parent = kobj->parent->dentry;
+	else if (sysfs_mount && sysfs_mount->mnt_sb)
+		parent = sysfs_mount->mnt_sb->s_root;
+	else
+		return -EFAULT;
+
+	down(&parent->d_inode->i_sem);
+	dentry = sysfs_get_dentry(parent,kobj->name);
+	if (!IS_ERR(dentry)) {
+		dentry->d_fsdata = (void *)kobj;
+		kobj->dentry = dentry;
+		error = sysfs_create(dentry,(S_IFDIR| S_IRWXU | S_IRUGO | S_IXUGO),
+				     init_dir);
+		if (!error)
+			parent->d_inode->i_nlink++;
+	} else
+		error = PTR_ERR(dentry);
+	up(&parent->d_inode->i_sem);
+
+	return error;
+}
+
+
+
+/**
+ *	sysfs_remove_dir - remove an object's directory.
+ *	@kobj:	object. 
+ *
+ *	The only thing special about this is that we remove any files in 
+ *	the directory before we remove the directory, and we've inlined
+ *	what used to be sysfs_rmdir() below, instead of calling separately.
+ */
+
+void sysfs_remove_dir(struct kobject * kobj)
+{
+	struct list_head * node, * next;
+	struct dentry * dentry = dget(kobj->dentry);
+	struct dentry * parent;
+
+	if (!dentry)
+		return;
+
+	pr_debug("sysfs %s: removing dir\n",dentry->d_name.name);
+	parent = dget(dentry->d_parent);
+	down(&parent->d_inode->i_sem);
+	down(&dentry->d_inode->i_sem);
+
+	list_for_each_safe(node,next,&dentry->d_subdirs) {
+		struct dentry * d = dget(list_entry(node,struct dentry,d_child));
+		/** 
+		 * Make sure dentry is still there 
+		 */
+		pr_debug(" o %s: ",d->d_name.name);
+		if (d->d_inode) {
+
+			pr_debug("removing");
+			/**
+			 * Unlink and unhash.
+			 */
+			simple_unlink(dentry->d_inode,d);
+			d_delete(d);
+
+			/**
+			 * Drop reference from initial sysfs_get_dentry().
+			 */
+			dput(d);
+		}
+		pr_debug(" done (%d)\n",atomic_read(&d->d_count));
+		/**
+		 * drop reference from dget() above.
+		 */
+		dput(d);
+	}
+
+	up(&dentry->d_inode->i_sem);
+	d_invalidate(dentry);
+	simple_rmdir(parent->d_inode,dentry);
+	d_delete(dentry);
+
+	pr_debug(" o %s removing done (%d)\n",dentry->d_name.name,
+		 atomic_read(&dentry->d_count));
+	/**
+	 * Drop reference from initial sysfs_get_dentry().
+	 */
+	dput(dentry);
+
+	/**
+	 * Drop reference from dget() on entrance.
+	 */
+	dput(dentry);
+	up(&parent->d_inode->i_sem);
+	dput(parent);
+}
+
+
+EXPORT_SYMBOL(sysfs_create_dir);
+EXPORT_SYMBOL(sysfs_remove_dir);
+

fs/sysfs/file.c

+/*
+ * file.c - operations for regular (text) files.
+ */
+
+#include <linux/module.h>
+#include <linux/dnotify.h>
+#include <linux/kobject.h>
+
+#include "sysfs.h"
+
+static struct file_operations sysfs_file_operations;
+
+static int init_file(struct inode * inode)
+{
+	inode->i_size = PAGE_SIZE;
+	inode->i_fop = &sysfs_file_operations;
+	return 0;
+}
+
+#define to_subsys(k) container_of(k,struct subsystem,kset.kobj)
+#define to_sattr(a) container_of(a,struct subsys_attribute,attr)
+
+/**
+ * Subsystem file operations.
+ * These operations allow subsystems to have files that can be 
+ * read/written. 
+ */
+static ssize_t 
+subsys_attr_show(struct kobject * kobj, struct attribute * attr, char * page)
+{
+	struct subsystem * s = to_subsys(kobj);
+	struct subsys_attribute * sattr = to_sattr(attr);
+	ssize_t ret = 0;
+
+	if (sattr->show)
+		ret = sattr->show(s,page);
+	return ret;
+}
+
+static ssize_t 
+subsys_attr_store(struct kobject * kobj, struct attribute * attr, 
+		  const char * page, size_t count)
+{
+	struct subsystem * s = to_subsys(kobj);
+	struct subsys_attribute * sattr = to_sattr(attr);
+	ssize_t ret = 0;
+
+	if (sattr->store)
+		ret = sattr->store(s,page,count);
+	return ret;
+}
+
+static struct sysfs_ops subsys_sysfs_ops = {
+	.show	= subsys_attr_show,
+	.store	= subsys_attr_store,
+};
+
+
+struct sysfs_buffer {
+	size_t			count;
+	loff_t			pos;
+	char			* page;
+	struct sysfs_ops	* ops;
+};
+
+
+/**
+ *	fill_read_buffer - allocate and fill buffer from object.
+ *	@file:		file pointer.
+ *	@buffer:	data buffer for file.
+ *
+ *	Allocate @buffer->page, if it hasn't been already, then call the
+ *	kobject's show() method to fill the buffer with this attribute's 
+ *	data. 
+ *	This is called only once, on the file's first read. 
+ */
+static int fill_read_buffer(struct file * file, struct sysfs_buffer * buffer)
+{
+	struct attribute * attr = file->f_dentry->d_fsdata;
+	struct kobject * kobj = file->f_dentry->d_parent->d_fsdata;
+	struct sysfs_ops * ops = buffer->ops;
+	int ret = 0;
+	size_t count;
+
+	if (!buffer->page)
+		buffer->page = (char *) __get_free_page(GFP_KERNEL);
+	if (!buffer->page)
+		return -ENOMEM;
+
+	count = ops->show(kobj,attr,buffer->page);
+	if (count >= 0)
+		buffer->count = count;
+	else
+		ret = count;
+	return ret;
+}
+
+
+/**
+ *	flush_read_buffer - push buffer to userspace.
+ *	@buffer:	data buffer for file.
+ *	@userbuf:	user-passed buffer.
+ *	@count:		number of bytes requested.
+ *	@ppos:		file position.
+ *
+ *	Copy the buffer we filled in fill_read_buffer() to userspace.
+ *	This is done at the reader's leisure, copying and advancing 
+ *	the amount they specify each time.
+ *	This may be called continuously until the buffer is empty.
+ */
+static int flush_read_buffer(struct sysfs_buffer * buffer, char * buf, 
+			     size_t count, loff_t * ppos)
+{
+	int error;
+
+	if (count > (buffer->count - *ppos))
+		count = buffer->count - *ppos;
+
+	error = copy_to_user(buf,buffer->page + *ppos,count);
+	if (!error)
+		*ppos += count;
+	return error ? -EFAULT : count;
+}
+
+/**
+ *	sysfs_read_file - read an attribute. 
+ *	@file:	file pointer.
+ *	@buf:	buffer to fill.
+ *	@count:	number of bytes to read.
+ *	@ppos:	starting offset in file.
+ *
+ *	Userspace wants to read an attribute file. The attribute descriptor
+ *	is in the file's ->d_fsdata. The target object is in the directory's
+ *	->d_fsdata.
+ *
+ *	We call fill_read_buffer() to allocate and fill the buffer from the
+ *	object's show() method exactly once (if the read is happening from
+ *	the beginning of the file). That should fill the entire buffer with
+ *	all the data the object has to offer for that attribute.
+ *	We then call flush_read_buffer() to copy the buffer to userspace
+ *	in the increments specified.
+ */
+
+static ssize_t
+sysfs_read_file(struct file *file, char *buf, size_t count, loff_t *ppos)
+{
+	struct sysfs_buffer * buffer = file->private_data;
+	ssize_t retval = 0;
+
+	if (!*ppos) {
+		if ((retval = fill_read_buffer(file,buffer)))
+			return retval;
+	}
+	pr_debug("%s: count = %d, ppos = %lld, buf = %s\n",
+		 __FUNCTION__,count,*ppos,buffer->page);
+	return flush_read_buffer(buffer,buf,count,ppos);
+}
+
+
+/**
+ *	fill_write_buffer - copy buffer from userspace.
+ *	@buffer:	data buffer for file.
+ *	@userbuf:	data from user.
+ *	@count:		number of bytes in @userbuf.
+ *
+ *	Allocate @buffer->page if it hasn't been already, then
+ *	copy the user-supplied buffer into it.
+ */
+
+static int 
+fill_write_buffer(struct sysfs_buffer * buffer, const char * buf, size_t count)
+{
+	int error;
+
+	if (!buffer->page)
+		buffer->page = (char *)__get_free_page(GFP_KERNEL);
+	if (!buffer->page)
+		return -ENOMEM;
+
+	if (count >= PAGE_SIZE)
+		count = PAGE_SIZE - 1;
+	error = copy_from_user(buffer->page,buf,count);
+	return error ? -EFAULT : count;
+}
+
+
+/**
+ *	flush_write_buffer - push buffer to kobject.
+ *	@file:		file pointer.
+ *	@buffer:	data buffer for file.
+ *
+ *	Get the correct pointers for the kobject and the attribute we're
+ *	dealing with, then call the store() method for the attribute, 
+ *	passing the buffer that we acquired in fill_write_buffer().
+ */
+
+static int 
+flush_write_buffer(struct file * file, struct sysfs_buffer * buffer, size_t count)
+{
+	struct attribute * attr = file->f_dentry->d_fsdata;
+	struct kobject * kobj = file->f_dentry->d_parent->d_fsdata;
+	struct sysfs_ops * ops = buffer->ops;
+
+	return ops->store(kobj,attr,buffer->page,count);
+}
+
+
+/**
+ *	sysfs_write_file - write an attribute.
+ *	@file:	file pointer
+ *	@buf:	data to write
+ *	@count:	number of bytes
+ *	@ppos:	starting offset
+ *
+ *	Similar to sysfs_read_file(), though working in the opposite direction.
+ *	We allocate and fill the data from the user in fill_write_buffer(),
+ *	then push it to the kobject in flush_write_buffer().
+ *	There is no easy way for us to know if userspace is only doing a partial
+ *	write, so we don't support them. We expect the entire buffer to come
+ *	on the first write. 
+ *	Hint: if you're writing a value, first read the file, modify only the
+ *	the value you're changing, then write entire buffer back. 
+ */
+
+static ssize_t
+sysfs_write_file(struct file *file, const char *buf, size_t count, loff_t *ppos)
+{
+	struct sysfs_buffer * buffer = file->private_data;
+
+	count = fill_write_buffer(buffer,buf,count);
+	if (count > 0)
+		count = flush_write_buffer(file,buffer,count);
+	if (count > 0)
+		*ppos += count;
+	return count;
+}
+
+static int check_perm(struct inode * inode, struct file * file)
+{
+	struct kobject * kobj = kobject_get(file->f_dentry->d_parent->d_fsdata);
+	struct attribute * attr = file->f_dentry->d_fsdata;
+	struct sysfs_buffer * buffer;
+	struct sysfs_ops * ops = NULL;
+	int error = 0;
+
+	if (!kobj || !attr)
+		goto Einval;
+
+	/* if the kobject has no ktype, then we assume that it is a subsystem
+	 * itself, and use ops for it.
+	 */
+	if (kobj->kset && kobj->kset->ktype)
+		ops = kobj->kset->ktype->sysfs_ops;
+	else if (kobj->ktype)
+		ops = kobj->ktype->sysfs_ops;
+	else
+		ops = &subsys_sysfs_ops;
+
+	/* No sysfs operations, either from having no subsystem,
+	 * or the subsystem have no operations.
+	 */
+	if (!ops)
+		goto Eaccess;
+
+	/* File needs write support.
+	 * The inode's perms must say it's ok, 
+	 * and we must have a store method.
+	 */
+	if (file->f_mode & FMODE_WRITE) {
+
+		if (!(inode->i_mode & S_IWUGO) || !ops->store)
+			goto Eaccess;
+
+	}
+
+	/* File needs read support.
+	 * The inode's perms must say it's ok, and we there
+	 * must be a show method for it.
+	 */
+	if (file->f_mode & FMODE_READ) {
+		if (!(inode->i_mode & S_IRUGO) || !ops->show)
+			goto Eaccess;
+	}
+
+	/* No error? Great, allocate a buffer for the file, and store it
+	 * it in file->private_data for easy access.
+	 */
+	buffer = kmalloc(sizeof(struct sysfs_buffer),GFP_KERNEL);
+	if (buffer) {
+		memset(buffer,0,sizeof(struct sysfs_buffer));
+		buffer->ops = ops;
+		file->private_data = buffer;
+	} else
+		error = -ENOMEM;
+	goto Done;
+
+ Einval:
+	error = -EINVAL;
+	goto Done;
+ Eaccess:
+	error = -EACCES;
+ Done:
+	if (error && kobj)
+		kobject_put(kobj);
+	return error;
+}
+
+static int sysfs_open_file(struct inode * inode, struct file * filp)
+{
+	return check_perm(inode,filp);
+}
+
+static int sysfs_release(struct inode * inode, struct file * filp)
+{
+	struct kobject * kobj = filp->f_dentry->d_parent->d_fsdata;
+	struct sysfs_buffer * buffer = filp->private_data;
+
+	if (kobj) 
+		kobject_put(kobj);
+
+	if (buffer) {
+		if (buffer->page)
+			free_page((unsigned long)buffer->page);
+		kfree(buffer);
+	}
+	return 0;
+}
+
+static struct file_operations sysfs_file_operations = {
+	.read		= sysfs_read_file,
+	.write		= sysfs_write_file,
+	.llseek		= generic_file_llseek,
+	.open		= sysfs_open_file,
+	.release	= sysfs_release,
+};
+
+/**
+ *	sysfs_create_file - create an attribute file for an object.
+ *	@kobj:	object we're creating for. 
+ *	@attr:	atrribute descriptor.
+ */
+
+int sysfs_create_file(struct kobject * kobj, struct attribute * attr)
+{
+	struct dentry * dentry;
+	struct dentry * parent;
+	int error = 0;
+
+	if (!kobj || !attr)
+		return -EINVAL;
+
+	parent = kobj->dentry;
+
+	down(&parent->d_inode->i_sem);
+	dentry = sysfs_get_dentry(parent,attr->name);
+	if (!IS_ERR(dentry)) {
+		dentry->d_fsdata = (void *)attr;
+		error = sysfs_create(dentry,(attr->mode & S_IALLUGO) | S_IFREG,init_file);
+	} else
+		error = PTR_ERR(dentry);
+	up(&parent->d_inode->i_sem);
+	return error;
+}
+
+
+/**
+ * sysfs_update_file - update the modified timestamp on an object attribute.
+ * @kobj: object we're acting for.
+ * @attr: attribute descriptor.
+ *
+ * Also call dnotify for the dentry, which lots of userspace programs
+ * use.
+ */
+int sysfs_update_file(struct kobject * kobj, struct attribute * attr)
+{
+	struct dentry * dir = kobj->dentry;
+	struct dentry * victim;
+	int res = -ENOENT;
+
+	down(&dir->d_inode->i_sem);
+	victim = sysfs_get_dentry(dir, attr->name);
+	if (!IS_ERR(victim)) {
+		/* make sure dentry is really there */
+		if (victim->d_inode && 
+		    (victim->d_parent->d_inode == dir->d_inode)) {
+			victim->d_inode->i_mtime = CURRENT_TIME;
+			dnotify_parent(victim, DN_MODIFY);
+
+			/**
+			 * Drop reference from initial sysfs_get_dentry().
+			 */
+			dput(victim);
+			res = 0;
+		}
+		
+		/**
+		 * Drop the reference acquired from sysfs_get_dentry() above.
+		 */
+		dput(victim);
+	}
+	up(&dir->d_inode->i_sem);
+
+	return res;
+}
+
+
+/**
+ *	sysfs_remove_file - remove an object attribute.
+ *	@kobj:	object we're acting for.
+ *	@attr:	attribute descriptor.
+ *
+ *	Hash the attribute name and kill the victim.
+ */
+
+void sysfs_remove_file(struct kobject * kobj, struct attribute * attr)
+{
+	sysfs_hash_and_remove(kobj->dentry,attr->name);
+}
+
+
+EXPORT_SYMBOL(sysfs_create_file);
+EXPORT_SYMBOL(sysfs_remove_file);
+EXPORT_SYMBOL(sysfs_update_file);
+

fs/sysfs/inode.c

 /*
- * sysfs.c - The filesystem to export kernel objects.
+ * inode.c - basic inode and dentry operations.
  *
- * Copyright (c) 2001, 2002 Patrick Mochel
- *
- *  This program is free software; you can redistribute it and/or modify
- *  it under the terms of the GNU General Public License as published by
- *  the Free Software Foundation; either version 2 of the License, or
- *  (at your option) any later version.
- *
- *  This program is distributed in the hope that it will be useful,
- *  but WITHOUT ANY WARRANTY; without even the implied warranty of
- *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- *  GNU General Public License for more details.
- *
- *  You should have received a copy of the GNU General Public License
- *  along with this program; if not, write to the Free Software
- *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
- *
- * This is a simple, ramfs-based filesystem, designed to export kernel 
- * objects, their attributes, and the linkgaes between each other.
+ * sysfs is Copyright (c) 2001-3 Patrick Mochel
  *
  * Please see Documentation/filesystems/sysfs.txt for more information.
  */
 
 #undef DEBUG 
 
-#include <linux/list.h>
-#include <linux/init.h>
 #include <linux/pagemap.h>
-#include <linux/stat.h>
-#include <linux/fs.h>
-#include <linux/dcache.h>
 #include <linux/namei.h>
-#include <linux/module.h>
-#include <linux/slab.h>
 #include <linux/backing-dev.h>
-#include <linux/kobject.h>
-#include <linux/mount.h>
-#include <linux/dnotify.h>
-#include <asm/uaccess.h>
-
-/* Random magic number */
-#define SYSFS_MAGIC 0x62656572
+extern struct super_block * sysfs_sb;
 
-static struct super_operations sysfs_ops;
-static struct file_operations sysfs_file_operations;
-static struct address_space_operations sysfs_aops;
-
-static struct vfsmount *sysfs_mount;
+static struct address_space_operations sysfs_aops = {
+	.readpage	= simple_readpage,
+	.prepare_write	= simple_prepare_write,
+	.commit_write	= simple_commit_write
+};
 
 static struct backing_dev_info sysfs_backing_dev_info = {
 	.ra_pages	= 0,	/* No readahead */
 	.memory_backed	= 1,	/* Does not contribute to dirty memory */
 };
 
-static struct inode *sysfs_get_inode(struct super_block *sb, int mode, int dev)
+struct inode * sysfs_new_inode(mode_t mode)
 {
-	struct inode *inode = new_inode(sb);
-
+	struct inode * inode = new_inode(sysfs_sb);
 	if (inode) {
 		inode->i_mode = mode;
 		inode->i_uid = current->fsuid;
@@ -68,472 +37,43 @@ static struct inode *sysfs_get_inode(struct super_block *sb, int mode, int dev)
 		inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
 		inode->i_mapping->a_ops = &sysfs_aops;
 		inode->i_mapping->backing_dev_info = &sysfs_backing_dev_info;
-		switch (mode & S_IFMT) {
-		default:
-			init_special_inode(inode, mode, dev);
-			break;
-		case S_IFREG:
-			inode->i_size = PAGE_SIZE;
-			inode->i_fop = &sysfs_file_operations;
-			break;
-		case S_IFDIR:
-			inode->i_op = &simple_dir_inode_operations;
-			inode->i_fop = &simple_dir_operations;
-
-			/* directory inodes start off with i_nlink == 2 (for "." entry) */
-			inode->i_nlink++;
-			break;
-		case S_IFLNK:
-			inode->i_op = &page_symlink_inode_operations;
-			break;
-		}
 	}
 	return inode;
 }
 
-static int sysfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
+int sysfs_create(struct dentry * dentry, int mode, int (*init)(struct inode *))
 {
-	struct inode *inode;
 	int error = 0;
-
+	struct inode * inode = NULL;
+	if (dentry) {
 		if (!dentry->d_inode) {
-		inode = sysfs_get_inode(dir->i_sb, mode, dev);
-		if (inode) {
-			d_instantiate(dentry, inode);
-			dget(dentry);
-		} else
-			error = -ENOSPC;
+			if ((inode = sysfs_new_inode(mode)))
+				goto Proceed;
+			else 
+				error = -ENOMEM;
 		} else
 			error = -EEXIST;
-	return error;
-}
-
-static int sysfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
-{
-	int res;
-	mode = (mode & (S_IRWXUGO|S_ISVTX)) | S_IFDIR;
- 	res = sysfs_mknod(dir, dentry, mode, 0);
- 	if (!res)
- 		dir->i_nlink++;
-	return res;
-}
-
-static int sysfs_create(struct inode *dir, struct dentry *dentry, int mode)
-{
-	int res;
-	mode = (mode & S_IALLUGO) | S_IFREG;
- 	res = sysfs_mknod(dir, dentry, mode, 0);
-	return res;
-}
-
-static int sysfs_symlink(struct inode * dir, struct dentry *dentry, const char * symname)
-{
-	struct inode *inode;
-	int error = -ENOSPC;
-
-	if (dentry->d_inode)
-		return -EEXIST;
-
-	inode = sysfs_get_inode(dir->i_sb, S_IFLNK|S_IRWXUGO, 0);
-	if (inode) {
-		int l = strlen(symname)+1;
-		error = page_symlink(inode, symname, l);
-		if (!error) {
-			d_instantiate(dentry, inode);
-			dget(dentry);
 	} else 
-			iput(inode);
-	}
-	return error;
-}
-
-#define to_subsys(k) container_of(k,struct subsystem,kset.kobj)
-#define to_sattr(a) container_of(a,struct subsys_attribute,attr)
-
-/**
- * Subsystem file operations.
- * These operations allow subsystems to have files that can be 
- * read/written. 
- */
-static ssize_t 
-subsys_attr_show(struct kobject * kobj, struct attribute * attr, char * page)
-{
-	struct subsystem * s = to_subsys(kobj);
-	struct subsys_attribute * sattr = to_sattr(attr);
-	ssize_t ret = 0;
-
-	if (sattr->show)
-		ret = sattr->show(s,page);
-	return ret;
-}
-
-static ssize_t 
-subsys_attr_store(struct kobject * kobj, struct attribute * attr, 
-		  const char * page, size_t count)
-{
-	struct subsystem * s = to_subsys(kobj);
-	struct subsys_attribute * sattr = to_sattr(attr);
-	ssize_t ret = 0;
-
-	if (sattr->store)
-		ret = sattr->store(s,page,count);
-	return ret;
-}
-
-static struct sysfs_ops subsys_sysfs_ops = {
-	.show	= subsys_attr_show,
-	.store	= subsys_attr_store,
-};
-
-
-struct sysfs_buffer {
-	size_t			count;
-	loff_t			pos;
-	char			* page;
-	struct sysfs_ops	* ops;
-};
-
-
-/**
- *	fill_read_buffer - allocate and fill buffer from object.
- *	@file:		file pointer.
- *	@buffer:	data buffer for file.
- *
- *	Allocate @buffer->page, if it hasn't been already, then call the
- *	kobject's show() method to fill the buffer with this attribute's 
- *	data. 
- *	This is called only once, on the file's first read. 
- */
-static int fill_read_buffer(struct file * file, struct sysfs_buffer * buffer)
-{
-	struct attribute * attr = file->f_dentry->d_fsdata;
-	struct kobject * kobj = file->f_dentry->d_parent->d_fsdata;
-	struct sysfs_ops * ops = buffer->ops;
-	int ret = 0;
-	ssize_t count;
-
-	if (!buffer->page)
-		buffer->page = (char *) __get_free_page(GFP_KERNEL);
-	if (!buffer->page)
-		return -ENOMEM;
-
-	count = ops->show(kobj,attr,buffer->page);
-	if (count >= 0)
-		buffer->count = count;
-	else
-		ret = count;
-	return ret;
-}
-
-
-/**
- *	flush_read_buffer - push buffer to userspace.
- *	@buffer:	data buffer for file.
- *	@userbuf:	user-passed buffer.
- *	@count:		number of bytes requested.
- *	@ppos:		file position.
- *
- *	Copy the buffer we filled in fill_read_buffer() to userspace.
- *	This is done at the reader's leisure, copying and advancing 
- *	the amount they specify each time.
- *	This may be called continuously until the buffer is empty.
- */
-static int flush_read_buffer(struct sysfs_buffer * buffer, char * buf, 
-			     size_t count, loff_t * ppos)
-{
-	int error;
-
-	if (count > (buffer->count - *ppos))
-		count = buffer->count - *ppos;
+		error = -ENOENT;
+	goto Done;
 
-	error = copy_to_user(buf,buffer->page + *ppos,count);
+ Proceed:
+	if (init)
+		error = init(inode);
 	if (!error)
-		*ppos += count;
-	return error ? -EFAULT : count;
-}
-
-/**
- *	sysfs_read_file - read an attribute. 
- *	@file:	file pointer.
- *	@buf:	buffer to fill.
- *	@count:	number of bytes to read.
- *	@ppos:	starting offset in file.
- *
- *	Userspace wants to read an attribute file. The attribute descriptor
- *	is in the file's ->d_fsdata. The target object is in the directory's
- *	->d_fsdata.
- *
- *	We call fill_read_buffer() to allocate and fill the buffer from the
- *	object's show() method exactly once (if the read is happening from
- *	the beginning of the file). That should fill the entire buffer with
- *	all the data the object has to offer for that attribute.
- *	We then call flush_read_buffer() to copy the buffer to userspace
- *	in the increments specified.
- */
-
-static ssize_t
-sysfs_read_file(struct file *file, char *buf, size_t count, loff_t *ppos)
-{
-	struct sysfs_buffer * buffer = file->private_data;
-	ssize_t retval = 0;
-
-	if (!*ppos) {
-		if ((retval = fill_read_buffer(file,buffer)))
-			return retval;
-	}
-	pr_debug("%s: count = %d, ppos = %lld, buf = %s\n",
-		 __FUNCTION__,count,*ppos,buffer->page);
-	return flush_read_buffer(buffer,buf,count,ppos);
-}
-
-
-/**
- *	fill_write_buffer - copy buffer from userspace.
- *	@buffer:	data buffer for file.
- *	@userbuf:	data from user.
- *	@count:		number of bytes in @userbuf.
- *
- *	Allocate @buffer->page if it hasn't been already, then
- *	copy the user-supplied buffer into it.
- */
-
-static int 
-fill_write_buffer(struct sysfs_buffer * buffer, const char * buf, size_t count)
-{
-	int error;
-
-	if (!buffer->page)
-		buffer->page = (char *)__get_free_page(GFP_KERNEL);
-	if (!buffer->page)
-		return -ENOMEM;
-
-	if (count >= PAGE_SIZE)
-		count = PAGE_SIZE - 1;
-	error = copy_from_user(buffer->page,buf,count);
-	return error ? -EFAULT : count;
-}
-
-
-/**
- *	flush_write_buffer - push buffer to kobject.
- *	@file:		file pointer.
- *	@buffer:	data buffer for file.
- *
- *	Get the correct pointers for the kobject and the attribute we're
- *	dealing with, then call the store() method for the attribute, 
- *	passing the buffer that we acquired in fill_write_buffer().
- */
-
-static int 
-flush_write_buffer(struct file * file, struct sysfs_buffer * buffer, size_t count)
-{
-	struct attribute * attr = file->f_dentry->d_fsdata;
-	struct kobject * kobj = file->f_dentry->d_parent->d_fsdata;
-	struct sysfs_ops * ops = buffer->ops;
-
-	return ops->store(kobj,attr,buffer->page,count);
-}
-
-
-/**
- *	sysfs_write_file - write an attribute.
- *	@file:	file pointer
- *	@buf:	data to write
- *	@count:	number of bytes
- *	@ppos:	starting offset
- *
- *	Similar to sysfs_read_file(), though working in the opposite direction.
- *	We allocate and fill the data from the user in fill_write_buffer(),
- *	then push it to the kobject in flush_write_buffer().
- *	There is no easy way for us to know if userspace is only doing a partial
- *	write, so we don't support them. We expect the entire buffer to come
- *	on the first write. 
- *	Hint: if you're writing a value, first read the file, modify only the
- *	the value you're changing, then write entire buffer back. 
- */
-
-static ssize_t
-sysfs_write_file(struct file *file, const char *buf, size_t count, loff_t *ppos)
-{
-	struct sysfs_buffer * buffer = file->private_data;
-
-	count = fill_write_buffer(buffer,buf,count);
-	if (count > 0)
-		count = flush_write_buffer(file,buffer,count);
-	if (count > 0)
-		*ppos += count;
-	return count;
-}
-
-static int check_perm(struct inode * inode, struct file * file)
-{
-	struct kobject * kobj = kobject_get(file->f_dentry->d_parent->d_fsdata);
-	struct attribute * attr = file->f_dentry->d_fsdata;
-	struct sysfs_buffer * buffer;
-	struct sysfs_ops * ops = NULL;
-	int error = 0;
-
-	if (!kobj || !attr)
-		goto Einval;
-
-	/* if the kobject has no ktype, then we assume that it is a subsystem
-	 * itself, and use ops for it.
-	 */
-	if (kobj->kset && kobj->kset->ktype)
-		ops = kobj->kset->ktype->sysfs_ops;
-	else if (kobj->ktype)
-		ops = kobj->ktype->sysfs_ops;
+		d_instantiate(dentry, inode);
 	else
-		ops = &subsys_sysfs_ops;
-
-	/* No sysfs operations, either from having no subsystem,
-	 * or the subsystem have no operations.
-	 */
-	if (!ops)
-		goto Eaccess;
-
-	/* File needs write support.
-	 * The inode's perms must say it's ok, 
-	 * and we must have a store method.
-	 */
-	if (file->f_mode & FMODE_WRITE) {
-
-		if (!(inode->i_mode & S_IWUGO) || !ops->store)
-			goto Eaccess;
-
-	}
-
-	/* File needs read support.
-	 * The inode's perms must say it's ok, and we there
-	 * must be a show method for it.
-	 */
-	if (file->f_mode & FMODE_READ) {
-		if (!(inode->i_mode & S_IRUGO) || !ops->show)
-			goto Eaccess;
-	}
-
-	/* No error? Great, allocate a buffer for the file, and store it
-	 * it in file->private_data for easy access.
-	 */
-	buffer = kmalloc(sizeof(struct sysfs_buffer),GFP_KERNEL);
-	if (buffer) {
-		memset(buffer,0,sizeof(struct sysfs_buffer));
-		buffer->ops = ops;
-		file->private_data = buffer;
-	} else
-		error = -ENOMEM;
-	goto Done;
-
- Einval:
-	error = -EINVAL;
-	goto Done;
- Eaccess:
-	error = -EACCES;
+		iput(inode);
  Done:
-	if (error && kobj)
-		kobject_put(kobj);
 	return error;
 }
 
-static int sysfs_open_file(struct inode * inode, struct file * filp)
-{
-	return check_perm(inode,filp);
-}
-
-static int sysfs_release(struct inode * inode, struct file * filp)
-{
-	struct kobject * kobj = filp->f_dentry->d_parent->d_fsdata;
-	struct sysfs_buffer * buffer = filp->private_data;
-
-	if (kobj) 
-		kobject_put(kobj);
-
-	if (buffer) {
-		if (buffer->page)
-			free_page((unsigned long)buffer->page);
-		kfree(buffer);
-	}
-	return 0;
-}
-
-static struct file_operations sysfs_file_operations = {
-	.read		= sysfs_read_file,
-	.write		= sysfs_write_file,
-	.llseek		= generic_file_llseek,
-	.open		= sysfs_open_file,
-	.release	= sysfs_release,
-};
-
-static struct address_space_operations sysfs_aops = {
-	.readpage	= simple_readpage,
-	.prepare_write	= simple_prepare_write,
-	.commit_write	= simple_commit_write
-};
-
-static struct super_operations sysfs_ops = {
-	.statfs		= simple_statfs,
-	.drop_inode	= generic_delete_inode,
-};
-
-static int sysfs_fill_super(struct super_block *sb, void *data, int silent)
-{
-	struct inode *inode;
-	struct dentry *root;
-
-	sb->s_blocksize = PAGE_CACHE_SIZE;
-	sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
-	sb->s_magic = SYSFS_MAGIC;
-	sb->s_op = &sysfs_ops;
-	inode = sysfs_get_inode(sb, S_IFDIR | 0755, 0);
-
-	if (!inode) {
-		pr_debug("%s: could not get inode!\n",__FUNCTION__);
-		return -ENOMEM;
-	}
-
-	root = d_alloc_root(inode);
-	if (!root) {
-		pr_debug("%s: could not get root dentry!\n",__FUNCTION__);
-		iput(inode);
-		return -ENOMEM;
-	}
-	sb->s_root = root;
-	return 0;
-}
-
-static struct super_block *sysfs_get_sb(struct file_system_type *fs_type,
-	int flags, char *dev_name, void *data)
-{
-	return get_sb_single(fs_type, flags, data, sysfs_fill_super);
-}
-
-static struct file_system_type sysfs_fs_type = {
-	.owner		= THIS_MODULE,
-	.name		= "sysfs",
-	.get_sb		= sysfs_get_sb,
-	.kill_sb	= kill_litter_super,
-};
-
-static int __init sysfs_init(void)
+int sysfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
 {
-	int err;
-
-	err = register_filesystem(&sysfs_fs_type);
-	if (!err) {
-		sysfs_mount = kern_mount(&sysfs_fs_type);
-		if (IS_ERR(sysfs_mount)) {
-			printk(KERN_ERR "sysfs: could not mount!\n");
-			err = PTR_ERR(sysfs_mount);
-			sysfs_mount = NULL;
-		}
-	}
-	return err;
+	return sysfs_create(dentry, mode, NULL);
 }
 
-core_initcall(sysfs_init);
-
-
-static struct dentry * get_dentry(struct dentry * parent, const char * name)
+struct dentry * sysfs_get_dentry(struct dentry * parent, const char * name)
 {
 	struct qstr qstr;
 
@@ -543,157 +83,12 @@ static struct dentry * get_dentry(struct dentry * parent, const char * name)
 	return lookup_hash(&qstr,parent);
 }
 
-
-/**
- *	sysfs_create_dir - create a directory for an object.
- *	@parent:	parent parent object.
- *	@kobj:		object we're creating directory for. 
- */
-
-int sysfs_create_dir(struct kobject * kobj)
-{
-	struct dentry * dentry = NULL;
-	struct dentry * parent;
-	int error = 0;
-
-	if (!kobj)
-		return -EINVAL;
-
-	if (kobj->parent)
-		parent = kobj->parent->dentry;
-	else if (sysfs_mount && sysfs_mount->mnt_sb)
-		parent = sysfs_mount->mnt_sb->s_root;
-	else
-		return -EFAULT;
-
-	down(&parent->d_inode->i_sem);
-	dentry = get_dentry(parent,kobj->name);
-	if (!IS_ERR(dentry)) {
-		dentry->d_fsdata = (void *)kobj;
-		kobj->dentry = dentry;
-		error = sysfs_mkdir(parent->d_inode,dentry,
-				    (S_IFDIR| S_IRWXU | S_IRUGO | S_IXUGO));
-	} else
-		error = PTR_ERR(dentry);
-	up(&parent->d_inode->i_sem);
-
-	return error;
-}
-
-
-/**
- *	sysfs_create_file - create an attribute file for an object.
- *	@kobj:	object we're creating for. 
- *	@attr:	atrribute descriptor.
- */
-
-int sysfs_create_file(struct kobject * kobj, struct attribute * attr)
-{
-	struct dentry * dentry;
-	struct dentry * parent;
-	int error = 0;
-
-	if (!kobj || !attr)
-		return -EINVAL;
-
-	parent = kobj->dentry;
-
-	down(&parent->d_inode->i_sem);
-	dentry = get_dentry(parent,attr->name);
-	if (!IS_ERR(dentry)) {
-		dentry->d_fsdata = (void *)attr;
-		error = sysfs_create(parent->d_inode,dentry,attr->mode);
-	} else
-		error = PTR_ERR(dentry);
-	up(&parent->d_inode->i_sem);
-	return error;
-}
-
-
-static int object_depth(struct kobject * kobj)
-{
-	struct kobject * p = kobj;
-	int depth = 0;
-	do { depth++; } while ((p = p->parent));
-	return depth;
-}
-
-static int object_path_length(struct kobject * kobj)
-{
-	struct kobject * p = kobj;
-	int length = 1;
-	do {
-		length += strlen(p->name) + 1;
-		p = p->parent;
-	} while (p);
-	return length;
-}
-
-static void fill_object_path(struct kobject * kobj, char * buffer, int length)
-{
-	struct kobject * p;
-
-	--length;
-	for (p = kobj; p; p = p->parent) {
-		int cur = strlen(p->name);
-
-		/* back up enough to print this bus id with '/' */
-		length -= cur;
-		strncpy(buffer + length,p->name,cur);
-		*(buffer + --length) = '/';
-	}
-}
-
-/**
- *	sysfs_create_link - create symlink between two objects.
- *	@kobj:	object whose directory we're creating the link in.
- *	@target:	object we're pointing to.
- *	@name:		name of the symlink.
- */
-int sysfs_create_link(struct kobject * kobj, struct kobject * target, char * name)
-{
-	struct dentry * dentry = kobj->dentry;
-	struct dentry * d;
-	int error = 0;
-	int size;
-	int depth;
-	char * path;
-	char * s;
-
-	depth = object_depth(kobj);
-	size = object_path_length(target) + depth * 3 - 1;
-	if (size > PATH_MAX)
-		return -ENAMETOOLONG;
-	pr_debug("%s: depth = %d, size = %d\n",__FUNCTION__,depth,size);
-
-	path = kmalloc(size,GFP_KERNEL);
-	if (!path)
-		return -ENOMEM;
-	memset(path,0,size);
-
-	for (s = path; depth--; s += 3)
-		strcpy(s,"../");
-
-	fill_object_path(target,path,size);
-	pr_debug("%s: path = '%s'\n",__FUNCTION__,path);
-
-	down(&dentry->d_inode->i_sem);
-	d = get_dentry(dentry,name);
-	if (!IS_ERR(d))
-		error = sysfs_symlink(dentry->d_inode,d,path);
-	else
-		error = PTR_ERR(d);
-	up(&dentry->d_inode->i_sem);
-	kfree(path);
-	return error;
-}
-
-static void hash_and_remove(struct dentry * dir, const char * name)
+void sysfs_hash_and_remove(struct dentry * dir, const char * name)
 {
 	struct dentry * victim;
 
 	down(&dir->d_inode->i_sem);
-	victim = get_dentry(dir,name);
+	victim = sysfs_get_dentry(dir,name);
 	if (!IS_ERR(victim)) {
 		/* make sure dentry is really there */
 		if (victim->d_inode && 
@@ -703,161 +98,18 @@ static void hash_and_remove(struct dentry * dir, const char * name)
 
 			pr_debug("sysfs: Removing %s (%d)\n", victim->d_name.name,
 				 atomic_read(&victim->d_count));
-			/**
-			 * Drop reference from initial get_dentry().
-			 */
-			dput(victim);
-		}
-		
-		/**
-		 * Drop the reference acquired from get_dentry() above.
-		 */
-		dput(victim);
-	}
-	up(&dir->d_inode->i_sem);
-}
-
-/**
- * sysfs_update_file - update the modified timestamp on an object attribute.
- * @kobj: object we're acting for.
- * @attr: attribute descriptor.
- *
- * Also call dnotify for the dentry, which lots of userspace programs
- * use.
- */
-int sysfs_update_file(struct kobject * kobj, struct attribute * attr)
-{
-	struct dentry * dir = kobj->dentry;
-	struct dentry * victim;
-	int res = -ENOENT;
-
-	down(&dir->d_inode->i_sem);
-	victim = get_dentry(dir, attr->name);
-	if (!IS_ERR(victim)) {
-		/* make sure dentry is really there */
-		if (victim->d_inode && 
-		    (victim->d_parent->d_inode == dir->d_inode)) {
-			victim->d_inode->i_mtime = CURRENT_TIME;
-			dnotify_parent(victim, DN_MODIFY);
-
-			/**
-			 * Drop reference from initial get_dentry().
+			/*
+			 * Drop reference from initial sysfs_get_dentry().
 			 */
 			dput(victim);
-			res = 0;
 		}
 		
 		/**
-		 * Drop the reference acquired from get_dentry() above.
+		 * Drop the reference acquired from sysfs_get_dentry() above.
 		 */
 		dput(victim);
 	}
 	up(&dir->d_inode->i_sem);
-
-	return res;
 }
 
 
-/**
- *	sysfs_remove_file - remove an object attribute.
- *	@kobj:	object we're acting for.
- *	@attr:	attribute descriptor.
- *
- *	Hash the attribute name and kill the victim.
- */
-
-void sysfs_remove_file(struct kobject * kobj, struct attribute * attr)
-{
-	hash_and_remove(kobj->dentry,attr->name);
-}
-
-
-/**
- *	sysfs_remove_link - remove symlink in object's directory.
- *	@kobj:	object we're acting for.
- *	@name:	name of the symlink to remove.
- */
-
-void sysfs_remove_link(struct kobject * kobj, char * name)
-{
-	hash_and_remove(kobj->dentry,name);
-}
-
-
-/**
- *	sysfs_remove_dir - remove an object's directory.
- *	@kobj:	object. 
- *
- *	The only thing special about this is that we remove any files in 
- *	the directory before we remove the directory, and we've inlined
- *	what used to be sysfs_rmdir() below, instead of calling separately.
- */
-
-void sysfs_remove_dir(struct kobject * kobj)
-{
-	struct list_head * node, * next;
-	struct dentry * dentry = dget(kobj->dentry);
-	struct dentry * parent;
-
-	if (!dentry)
-		return;
-
-	pr_debug("sysfs %s: removing dir\n",dentry->d_name.name);
-	parent = dget(dentry->d_parent);
-	down(&parent->d_inode->i_sem);
-	down(&dentry->d_inode->i_sem);
-
-	list_for_each_safe(node,next,&dentry->d_subdirs) {
-		struct dentry * d = dget(list_entry(node,struct dentry,d_child));
-		/** 
-		 * Make sure dentry is still there 
-		 */
-		pr_debug(" o %s: ",d->d_name.name);
-		if (d->d_inode) {
-
-			pr_debug("removing");
-			/**
-			 * Unlink and unhash.
-			 */
-			simple_unlink(dentry->d_inode,d);
-			d_delete(d);
-
-			/**
-			 * Drop reference from initial get_dentry().
-			 */
-			dput(d);
-		}
-		pr_debug(" done (%d)\n",atomic_read(&d->d_count));
-		/**
-		 * drop reference from dget() above.
-		 */
-		dput(d);
-	}
-
-	up(&dentry->d_inode->i_sem);
-	d_invalidate(dentry);
-	simple_rmdir(parent->d_inode,dentry);
-	d_delete(dentry);
-
-	pr_debug(" o %s removing done (%d)\n",dentry->d_name.name,
-		 atomic_read(&dentry->d_count));
-	/**
-	 * Drop reference from initial get_dentry().
-	 */
-	dput(dentry);
-
-	/**
-	 * Drop reference from dget() on entrance.
-	 */
-	dput(dentry);
-	up(&parent->d_inode->i_sem);
-	dput(parent);
-}
-
-EXPORT_SYMBOL(sysfs_create_file);
-EXPORT_SYMBOL(sysfs_update_file);
-EXPORT_SYMBOL(sysfs_remove_file);
-EXPORT_SYMBOL(sysfs_create_link);
-EXPORT_SYMBOL(sysfs_remove_link);
-EXPORT_SYMBOL(sysfs_create_dir);
-EXPORT_SYMBOL(sysfs_remove_dir);

fs/sysfs/mount.c

+/*
+ * mount.c - operations for initializing and mounting sysfs.
+ */
+
+#define DEBUG 
+
+#include <linux/fs.h>
+#include <linux/mount.h>
+#include <linux/pagemap.h>
+
+#include "sysfs.h"
+
+/* Random magic number */
+#define SYSFS_MAGIC 0x62656572
+
+struct vfsmount *sysfs_mount;
+struct super_block * sysfs_sb = NULL;
+
+static struct super_operations sysfs_ops = {
+	.statfs		= simple_statfs,
+	.drop_inode	= generic_delete_inode,
+};
+
+static int sysfs_fill_super(struct super_block *sb, void *data, int silent)
+{
+	struct inode *inode;
+	struct dentry *root;
+
+	sb->s_blocksize = PAGE_CACHE_SIZE;
+	sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
+	sb->s_magic = SYSFS_MAGIC;
+	sb->s_op = &sysfs_ops;
+	sysfs_sb = sb;
+
+	inode = sysfs_new_inode(S_IFDIR | S_IRUGO | S_IWUSR);
+	if (inode) {
+		inode->i_op = &simple_dir_inode_operations;
+		inode->i_fop = &simple_dir_operations;
+		/* directory inodes start off with i_nlink == 2 (for "." entry) */
+		inode->i_nlink++;	
+	} else {
+		pr_debug("sysfs: could not get root inode\n");
+		return -ENOMEM;
+	}
+
+	root = d_alloc_root(inode);
+	if (!root) {
+		pr_debug("%s: could not get root dentry!\n",__FUNCTION__);
+		iput(inode);
+		return -ENOMEM;
+	}
+	sb->s_root = root;
+	return 0;
+}
+
+static struct super_block *sysfs_get_sb(struct file_system_type *fs_type,
+	int flags, char *dev_name, void *data)
+{
+	return get_sb_single(fs_type, flags, data, sysfs_fill_super);
+}
+
+static struct file_system_type sysfs_fs_type = {
+	.name		= "sysfs",
+	.get_sb		= sysfs_get_sb,
+	.kill_sb	= kill_litter_super,
+};
+
+static int __init sysfs_init(void)
+{
+	int err;
+
+	err = register_filesystem(&sysfs_fs_type);
+	if (!err) {
+		sysfs_mount = kern_mount(&sysfs_fs_type);
+		if (IS_ERR(sysfs_mount)) {
+			printk(KERN_ERR "sysfs: could not mount!\n");
+			err = PTR_ERR(sysfs_mount);
+			sysfs_mount = NULL;
+		}
+	}
+	return err;
+}
+
+core_initcall(sysfs_init);

fs/sysfs/symlink.c

+/*
+ * symlink.c - operations for sysfs symlinks.
+ */
+
+#include <linux/fs.h>
+#include <linux/module.h>
+#include <linux/kobject.h>
+
+#include "sysfs.h"
+
+
+static int init_symlink(struct inode * inode)
+{
+	inode->i_op = &page_symlink_inode_operations;
+	return 0;
+}
+
+static int sysfs_symlink(struct inode * dir, struct dentry *dentry, const char * symname)
+{
+	int error;
+
+	error = sysfs_create(dentry, S_IFLNK|S_IRWXUGO, init_symlink);
+	if (!error) {
+		int l = strlen(symname)+1;
+		error = page_symlink(dentry->d_inode, symname, l);
+		if (error)
+			iput(dentry->d_inode);
+	}
+	return error;
+}
+
+static int object_depth(struct kobject * kobj)
+{
+	struct kobject * p = kobj;
+	int depth = 0;
+	do { depth++; } while ((p = p->parent));
+	return depth;
+}
+
+static int object_path_length(struct kobject * kobj)
+{
+	struct kobject * p = kobj;
+	int length = 1;
+	do {
+		length += strlen(p->name) + 1;
+		p = p->parent;
+	} while (p);
+	return length;
+}
+
+static void fill_object_path(struct kobject * kobj, char * buffer, int length)
+{
+	struct kobject * p;
+
+	--length;
+	for (p = kobj; p; p = p->parent) {
+		int cur = strlen(p->name);
+
+		/* back up enough to print this bus id with '/' */
+		length -= cur;
+		strncpy(buffer + length,p->name,cur);
+		*(buffer + --length) = '/';
+	}
+}
+
+/**
+ *	sysfs_create_link - create symlink between two objects.
+ *	@kobj:	object whose directory we're creating the link in.
+ *	@target:	object we're pointing to.
+ *	@name:		name of the symlink.
+ */
+int sysfs_create_link(struct kobject * kobj, struct kobject * target, char * name)
+{
+	struct dentry * dentry = kobj->dentry;
+	struct dentry * d;
+	int error = 0;
+	int size;
+	int depth;
+	char * path;
+	char * s;
+
+	depth = object_depth(kobj);
+	size = object_path_length(target) + depth * 3 - 1;
+	if (size > PATH_MAX)
+		return -ENAMETOOLONG;
+	pr_debug("%s: depth = %d, size = %d\n",__FUNCTION__,depth,size);
+
+	path = kmalloc(size,GFP_KERNEL);
+	if (!path)
+		return -ENOMEM;
+	memset(path,0,size);
+
+	for (s = path; depth--; s += 3)
+		strcpy(s,"../");
+
+	fill_object_path(target,path,size);
+	pr_debug("%s: path = '%s'\n",__FUNCTION__,path);
+
+	down(&dentry->d_inode->i_sem);
+	d = sysfs_get_dentry(dentry,name);
+	if (!IS_ERR(d))
+		error = sysfs_symlink(dentry->d_inode,d,path);
+	else
+		error = PTR_ERR(d);
+	up(&dentry->d_inode->i_sem);
+	kfree(path);
+	return error;
+}
+
+
+/**
+ *	sysfs_remove_link - remove symlink in object's directory.
+ *	@kobj:	object we're acting for.
+ *	@name:	name of the symlink to remove.
+ */
+
+void sysfs_remove_link(struct kobject * kobj, char * name)
+{
+	sysfs_hash_and_remove(kobj->dentry,name);
+}
+
+
+EXPORT_SYMBOL(sysfs_create_link);
+EXPORT_SYMBOL(sysfs_remove_link);
+

fs/sysfs/sysfs.h

+
+extern struct vfsmount * sysfs_mount;
+
+extern struct inode * sysfs_new_inode(mode_t mode);
+extern int sysfs_create(struct dentry *, int mode, int (*init)(struct inode *));
+
+extern struct dentry * sysfs_get_dentry(struct dentry *, char *);
+
+extern void sysfs_hash_and_remove(struct dentry * dir, const char * name);
+

include/linux/cpufreq.h

@@ -67,7 +67,8 @@ struct cpufreq_policy {
         unsigned int            policy; /* see above */
 	struct cpufreq_governor *governor; /* see below */
 	struct cpufreq_cpuinfo  cpuinfo;     /* see above */
-	struct intf_data        intf;   /* interface data */
+	struct device		* dev;
+	struct kobject		kobj;
 };
 
 #define CPUFREQ_ADJUST          (0)

include/linux/device.h

@@ -27,9 +27,9 @@
 #include <linux/ioport.h>
 #include <linux/kobject.h>
 #include <linux/list.h>
-#include <linux/sched.h>
 #include <linux/spinlock.h>
 #include <linux/types.h>
+#include <asm/semaphore.h>
 #include <asm/atomic.h>
 
 #define DEVICE_NAME_SIZE	50
@@ -207,8 +207,6 @@ extern void devclass_remove_file(struct device_class *, struct devclass_attribut
  * it supports the device.
  */
 
-struct intf_data;
-
 struct device_interface {
 	char			* name;
 	struct device_class	* devclass;
@@ -217,41 +215,19 @@ struct device_interface {
 	u32			devnum;
 
 	int (*add_device)	(struct device *);
-	int (*remove_device)	(struct intf_data *);
+	int (*remove_device)	(struct device *);
 };
 
 extern int interface_register(struct device_interface *);
 extern void interface_unregister(struct device_interface *);
 
 
-/*
- * intf_data - per-device data for an interface
- * Each interface typically has a per-device data structure 
- * that it allocates. It should embed one of these structures 
- * in that structure and call interface_add_data() to add it
- * to the device's list.
- * That will also enumerate the device within the interface
- * and create a driverfs symlink for it.
- */
-struct intf_data {
-	struct device_interface	* intf;
-	struct device		* dev;
-	u32			intf_num;
-	struct list_head	dev_entry;
-	struct kobject		kobj;
-};
-
-extern int interface_add_data(struct intf_data *);
-
-
-
 struct device {
 	struct list_head node;		/* node in sibling list */
 	struct list_head bus_list;	/* node in bus's list */
 	struct list_head class_list;
 	struct list_head driver_list;
 	struct list_head children;
-	struct list_head intf_list;
 	struct device 	* parent;
 
 	struct kobject kobj;

include/linux/kobject.h

@@ -73,7 +73,7 @@ extern void kset_unregister(struct kset * k);
 
 static inline struct kset * to_kset(struct kobject * kobj)
 {
-	return container_of(kobj,struct kset,kobj);
+	return kobj ? container_of(kobj,struct kset,kobj) : NULL;
 }
 
 static inline struct kset * kset_get(struct kset * k)

include/linux/pnpbios.h

@@ -85,8 +85,8 @@
 #define PNPBIOS_BOOTABLE		0x0010
 #define PNPBIOS_DOCK			0x0020
 #define PNPBIOS_REMOVABLE		0x0040
-#define pnpbios_is_static(x) ((x)->flags & 0x0100) == 0x0000
-#define pnpbios_is_dynamic(x) (x)->flags & 0x0080
+#define pnpbios_is_static(x) (((x)->flags & 0x0100) == 0x0000)
+#define pnpbios_is_dynamic(x) ((x)->flags & 0x0080)
 
 /* 0x8000 through 0xffff are OEM defined */
 

include/linux/sysfs.h

@@ -16,6 +16,20 @@ struct attribute {
 	mode_t			mode;
 };
 
+struct sysfs_bin_buffer {
+	u8 * 	data;
+	size_t	size;
+	size_t	count;
+	loff_t	offset;
+};
+
+struct bin_attribute {
+	struct attribute	attr;
+	size_t			size;
+	ssize_t (*read)(struct kobject *, struct sysfs_bin_buffer *);
+	ssize_t (*write)(struct kobject *, struct sysfs_bin_buffer *);
+};
+
 struct sysfs_ops {
 	ssize_t	(*show)(struct kobject *, struct attribute *,char *);
 	ssize_t	(*store)(struct kobject *,struct attribute *,const char *, size_t);

kernel/cpufreq.c

@@ -88,7 +88,7 @@ EXPORT_SYMBOL_GPL(cpufreq_parse_governor);
 
 /* forward declarations */
 static int cpufreq_add_dev (struct device * dev);
-static int cpufreq_remove_dev (struct intf_data * dev);
+static int cpufreq_remove_dev (struct device * dev);
 
 /* drivers/base/cpu.c */
 extern struct device_class cpu_devclass;
@@ -116,70 +116,59 @@ static inline int to_cpu_nr (struct device *dev)
  * "unsigned int".
  */
 
-#define cpufreq_per_cpu_attr_read(file_name, object) 			\
+#define show_one(file_name, object)		 			\
 static ssize_t show_##file_name 					\
-(struct device *dev, char *buf)						\
+(struct cpufreq_policy * policy, char *buf)				\
 {									\
 	unsigned int value = 0;						\
 									\
-	if (!dev)							\
-		return 0;						\
-									\
 	down(&cpufreq_driver_sem);					\
 	if (cpufreq_driver)						\
-		value = cpufreq_driver->policy[to_cpu_nr(dev)].object;	\
+		value = policy->object;					\
 	up(&cpufreq_driver_sem);					\
 									\
 	return sprintf (buf, "%u\n", value);				\
 }
 
+show_one(cpuinfo_min_freq, cpuinfo.min_freq);
+show_one(cpuinfo_max_freq, cpuinfo.max_freq);
+show_one(scaling_min_freq, min);
+show_one(scaling_max_freq, max);
 
 /**
  * cpufreq_per_cpu_attr_write() / store_##file_name() - sysfs write access
  */
-#define cpufreq_per_cpu_attr_write(file_name, object)			\
+#define store_one(file_name, object)			\
 static ssize_t store_##file_name					\
-(struct device *dev, const char *buf, size_t count)			\
+(struct cpufreq_policy * policy, const char *buf, size_t count)		\
 {									\
 	unsigned int ret = -EINVAL;					\
-	struct cpufreq_policy policy;					\
-									\
-	if (!dev)							\
-		return 0;						\
 									\
-	ret = cpufreq_get_policy(&policy, to_cpu_nr(dev));		\
-	if (ret)							\
-		return ret;						\
-									\
-	ret = sscanf (buf, "%u", &policy.object);			\
+	ret = sscanf (buf, "%u", &policy->object);			\
 	if (ret != 1)							\
 		return -EINVAL;						\
 									\
-	ret = cpufreq_set_policy(&policy);				\
-	if (ret)							\
-		return ret;						\
+	ret = cpufreq_set_policy(policy);				\
 									\
-	return count;							\
+	return ret ? ret : count;					\
 }
 
+store_one(scaling_min_freq,min);
+store_one(scaling_max_freq,max);
 
 /**
  * show_scaling_governor - show the current policy for the specified CPU
  */
-static ssize_t show_scaling_governor (struct device *dev, char *buf)
+static ssize_t show_scaling_governor (struct cpufreq_policy * policy, char *buf)
 {
 	unsigned int value = 0;
 	char value2[CPUFREQ_NAME_LEN];
 
-
-	if (!dev)
-		return 0;
-
 	down(&cpufreq_driver_sem);
 	if (cpufreq_driver)
-		value = cpufreq_driver->policy[to_cpu_nr(dev)].policy;
+		value = policy->policy;
 	if (value == CPUFREQ_POLICY_GOVERNOR)
-		strncpy(value2, cpufreq_driver->policy[to_cpu_nr(dev)].governor->name, CPUFREQ_NAME_LEN);
+		strncpy(value2, policy->governor->name, CPUFREQ_NAME_LEN);
 	up(&cpufreq_driver_sem);
 
 	switch (value) {
@@ -198,34 +187,88 @@ static ssize_t show_scaling_governor (struct device *dev, char *buf)
 /**
  * store_scaling_governor - store policy for the specified CPU
  */
-static ssize_t 
-store_scaling_governor (struct device *dev, const char *buf, size_t count) 
+static ssize_t store_scaling_governor (struct cpufreq_policy * policy, 
+				       const char *buf, size_t count) 
 {
 	unsigned int ret = -EINVAL;
 	char	str_governor[16];
-	struct cpufreq_policy policy;
-
-	if (!dev)
-		return 0;
-
-	ret = cpufreq_get_policy(&policy, to_cpu_nr(dev));
-	if (ret)
-		return ret;
 
 	ret = sscanf (buf, "%15s", str_governor);
 	if (ret != 1)
 		return -EINVAL;
 
-	if (cpufreq_parse_governor(str_governor, &policy.policy, &policy.governor))
+	if (cpufreq_parse_governor(str_governor, &policy->policy, &policy->governor))
 		return -EINVAL;
 
-	ret = cpufreq_set_policy(&policy);
-	if (ret)
-		return ret;
+	ret = cpufreq_set_policy(policy);
+
+	return ret ? ret : count;
+}
+
+
+struct freq_attr {
+	struct attribute attr;
+	ssize_t (*show)(struct cpufreq_policy *, char *);
+	ssize_t (*store)(struct cpufreq_policy *, const char *, size_t count);
+};
 
-	return count;
+#define define_one_ro(_name) \
+struct freq_attr _name = { \
+	.attr = { .name = __stringify(_name), .mode = 0444 }, \
+	.show = show_##_name, \
 }
 
+#define define_one_rw(_name) \
+struct freq_attr _name = { \
+	.attr = { .name = __stringify(_name), .mode = 0644 }, \
+	.show = show_##_name, \
+	.store = store_##_name, \
+}
+
+define_one_ro(cpuinfo_min_freq);
+define_one_ro(cpuinfo_max_freq);
+define_one_rw(scaling_min_freq);
+define_one_rw(scaling_max_freq);
+define_one_rw(scaling_governor);
+
+static struct attribute * default_attrs[] = {
+	&cpuinfo_min_freq.attr,
+	&cpuinfo_max_freq.attr,
+	&scaling_min_freq.attr,
+	&scaling_max_freq.attr,
+	&scaling_governor.attr,
+	NULL
+};
+
+
+#define to_policy(k) container_of(k,struct cpufreq_policy,kobj)
+#define to_attr(a) container_of(a,struct freq_attr,attr)
+
+static ssize_t show(struct kobject * kobj, struct attribute * attr ,char * buf)
+{
+	struct cpufreq_policy * policy = to_policy(kobj);
+	struct freq_attr * fattr = to_attr(attr);
+	return fattr->show ? fattr->show(policy,buf) : 0;
+}
+
+static ssize_t store(struct kobject * kobj, struct attribute * attr, 
+		     const char * buf, size_t count)
+{
+	struct cpufreq_policy * policy = to_policy(kobj);
+	struct freq_attr * fattr = to_attr(attr);
+	return fattr->store ? fattr->store(policy,buf,count) : 0;
+}
+
+static struct sysfs_ops sysfs_ops = {
+	.show	= show,
+	.store	= store,
+};
+
+static struct kobj_type ktype_cpufreq = {
+	.sysfs_ops	= &sysfs_ops,
+	.default_attrs	= default_attrs,
+};
+
 
 /**
  * show_scaling_governor - show the current policy for the specified CPU
@@ -274,34 +317,9 @@ static ssize_t show_available_govs(struct device *dev, char *buf)
 }
 
 
-/**
- * cpufreq_per_cpu_attr_ro - read-only cpufreq per-CPU file
- */
-#define cpufreq_per_cpu_attr_ro(file_name, object)			\
-cpufreq_per_cpu_attr_read(file_name, object) 				\
-static DEVICE_ATTR(file_name, S_IRUGO, show_##file_name, NULL);
-
-
-/**
- * cpufreq_per_cpu_attr_rw - read-write cpufreq per-CPU file
- */
-#define cpufreq_per_cpu_attr_rw(file_name, object) 			\
-cpufreq_per_cpu_attr_read(file_name, object) 				\
-cpufreq_per_cpu_attr_write(file_name, object) 				\
-static DEVICE_ATTR(file_name, (S_IRUGO | S_IWUSR), show_##file_name, store_##file_name);
-
-
-/* create the file functions */
-cpufreq_per_cpu_attr_ro(cpuinfo_min_freq, cpuinfo.min_freq);
-cpufreq_per_cpu_attr_ro(cpuinfo_max_freq, cpuinfo.max_freq);
-cpufreq_per_cpu_attr_rw(scaling_min_freq, min);
-cpufreq_per_cpu_attr_rw(scaling_max_freq, max);
-
-static DEVICE_ATTR(scaling_governor, (S_IRUGO | S_IWUSR), show_scaling_governor, store_scaling_governor);
 static DEVICE_ATTR(scaling_driver, S_IRUGO, show_scaling_driver, NULL);
 static DEVICE_ATTR(available_scaling_governors, S_IRUGO, show_available_govs, NULL);
 
-
 /**
  * cpufreq_add_dev - add a CPU device
  *
@@ -346,28 +364,13 @@ static int cpufreq_add_dev (struct device * dev)
 	down(&cpufreq_driver_sem);
 
 	/* prepare interface data */
-	cpufreq_driver->policy[cpu].intf.dev  = dev;
-	cpufreq_driver->policy[cpu].intf.intf = &cpufreq_interface;
-	strncpy(cpufreq_driver->policy[cpu].intf.kobj.name, cpufreq_interface.name, KOBJ_NAME_LEN);
-	cpufreq_driver->policy[cpu].intf.kobj.parent = &(dev->kobj);
-	cpufreq_driver->policy[cpu].intf.kobj.kset = &(cpufreq_interface.kset);
-
-	/* add interface */
-	/* currently commented out due to deadlock */
-	//ret = interface_add_data(&(cpufreq_driver->policy[cpu].intf));
-	if (ret) {
-		up(&cpufreq_driver_sem);
-		return ret;
-	}
+	policy.kobj.parent = &dev->kobj;
+	policy.kobj.ktype = &ktype_cpufreq;
+	policy.dev = dev;
+	strncpy(policy.kobj.name, 
+		cpufreq_interface.name, KOBJ_NAME_LEN);
 
-	/* create files */
-	device_create_file (dev, &dev_attr_cpuinfo_min_freq);
-	device_create_file (dev, &dev_attr_cpuinfo_max_freq);
-	device_create_file (dev, &dev_attr_scaling_min_freq);
-	device_create_file (dev, &dev_attr_scaling_max_freq);
-	device_create_file (dev, &dev_attr_scaling_governor);
-	device_create_file (dev, &dev_attr_scaling_driver);
-	device_create_file (dev, &dev_attr_available_scaling_governors);
+	ret = kobject_register(&policy.kobj);
 
 	up(&cpufreq_driver_sem);
 	return ret;
@@ -380,9 +383,8 @@ static int cpufreq_add_dev (struct device * dev)
  * Removes the cpufreq interface for a CPU device. Is called with
  * cpufreq_driver_sem locked.
  */
-static int cpufreq_remove_dev (struct intf_data *intf)
+static int cpufreq_remove_dev (struct device * dev)
 {
-	struct device * dev = intf->dev;
 	unsigned int cpu = to_cpu_nr(dev);
 
 	if (cpufreq_driver->target)
@@ -391,13 +393,7 @@ static int cpufreq_remove_dev (struct intf_data *intf)
 	if (cpufreq_driver->exit)
 		cpufreq_driver->exit(&cpufreq_driver->policy[cpu]);
 
-	device_remove_file (dev, &dev_attr_cpuinfo_min_freq);
-	device_remove_file (dev, &dev_attr_cpuinfo_max_freq);
-	device_remove_file (dev, &dev_attr_scaling_min_freq);
-	device_remove_file (dev, &dev_attr_scaling_max_freq);
-	device_remove_file (dev, &dev_attr_scaling_governor);
-	device_remove_file (dev, &dev_attr_scaling_driver);
-	device_remove_file (dev, &dev_attr_available_scaling_governors);
+	kobject_unregister(&cpufreq_driver->policy[cpu].kobj);
 
 	return 0;
 }
@@ -851,15 +847,6 @@ int cpufreq_unregister_driver(struct cpufreq_driver *driver)
 		return -EINVAL;
 	}
 
-	/* remove this workaround as soon as interface_add_data works */
-	{
-		unsigned int i;
-		for (i=0; i<NR_CPUS; i++) {
-			if (cpu_online(i)) 
-				cpufreq_remove_dev(&cpufreq_driver->policy[i].intf);
-		}
-	}
-
 	interface_unregister(&cpufreq_interface);
 
 	if (driver)