1 files changed, 268 insertions, 607 deletions

diff --git a/fs/sysfs/file.c b/fs/sysfs/file.c
index 15ef5eb1366..e9ef59b3abb 100644
--- a/fs/sysfs/file.c
+++ b/fs/sysfs/file.c
@@ -14,77 +14,56 @@
 #include <linux/kobject.h>
 #include <linux/kallsyms.h>
 #include <linux/slab.h>
-#include <linux/fsnotify.h>
-#include <linux/namei.h>
-#include <linux/poll.h>
 #include <linux/list.h>
 #include <linux/mutex.h>
-#include <linux/limits.h>
-#include <linux/uaccess.h>
+#include <linux/seq_file.h>
 
 #include "sysfs.h"
+#include "../kernfs/kernfs-internal.h"
 
 /*
- * There's one sysfs_buffer for each open file and one
- * sysfs_open_dirent for each sysfs_dirent with one or more open
- * files.
- *
- * filp->private_data points to sysfs_buffer and
- * sysfs_dirent->s_attr.open points to sysfs_open_dirent.  s_attr.open
- * is protected by sysfs_open_dirent_lock.
+ * Determine ktype->sysfs_ops for the given kernfs_node.  This function
+ * must be called while holding an active reference.
  */
-static DEFINE_SPINLOCK(sysfs_open_dirent_lock);
-
-struct sysfs_open_dirent {
-	atomic_t		refcnt;
-	atomic_t		event;
-	wait_queue_head_t	poll;
-	struct list_head	buffers; /* goes through sysfs_buffer.list */
-};
+static const struct sysfs_ops *sysfs_file_ops(struct kernfs_node *kn)
+{
+	struct kobject *kobj = kn->parent->priv;
 
-struct sysfs_buffer {
-	size_t			count;
-	loff_t			pos;
-	char			*page;
-	const struct sysfs_ops	*ops;
-	struct mutex		mutex;
-	int			needs_read_fill;
-	int			event;
-	struct list_head	list;
-};
+	if (kn->flags & KERNFS_LOCKDEP)
+		lockdep_assert_held(kn);
+	return kobj->ktype ? kobj->ktype->sysfs_ops : NULL;
+}
 
-/**
- *	fill_read_buffer - allocate and fill buffer from object.
- *	@dentry:	dentry 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 unless an error
- *	is returned.
+/*
+ * Reads on sysfs are handled through seq_file, which takes care of hairy
+ * details like buffering and seeking.  The following function pipes
+ * sysfs_ops->show() result through seq_file.
  */
-static int fill_read_buffer(struct dentry *dentry, struct sysfs_buffer *buffer)
+static int sysfs_kf_seq_show(struct seq_file *sf, void *v)
 {
-	struct sysfs_dirent *attr_sd = dentry->d_fsdata;
-	struct kobject *kobj = attr_sd->s_parent->s_dir.kobj;
-	const struct sysfs_ops *ops = buffer->ops;
-	int ret = 0;
+	struct kernfs_open_file *of = sf->private;
+	struct kobject *kobj = of->kn->parent->priv;
+	const struct sysfs_ops *ops = sysfs_file_ops(of->kn);
 	ssize_t count;
+	char *buf;
 
-	if (!buffer->page)
-		buffer->page = (char *) get_zeroed_page(GFP_KERNEL);
-	if (!buffer->page)
-		return -ENOMEM;
-
-	/* need attr_sd for attr and ops, its parent for kobj */
-	if (!sysfs_get_active(attr_sd))
-		return -ENODEV;
-
-	buffer->event = atomic_read(&attr_sd->s_attr.open->event);
-	count = ops->show(kobj, attr_sd->s_attr.attr, buffer->page);
+	/* acquire buffer and ensure that it's >= PAGE_SIZE and clear */
+	count = seq_get_buf(sf, &buf);
+	if (count < PAGE_SIZE) {
+		seq_commit(sf, -1);
+		return 0;
+	}
+	memset(buf, 0, PAGE_SIZE);
 
-	sysfs_put_active(attr_sd);
+	/*
+	 * Invoke show().  Control may reach here via seq file lseek even
+	 * if @ops->show() isn't implemented.
+	 */
+	if (ops->show) {
+		count = ops->show(kobj, of->kn->priv, buf);
+		if (count < 0)
+			return count;
+	}
 
 	/*
 	 * The code works fine with PAGE_SIZE return but it's likely to
@@ -96,486 +75,215 @@ static int fill_read_buffer(struct dentry *dentry, struct sysfs_buffer *buffer)
 		/* Try to struggle along */
 		count = PAGE_SIZE - 1;
 	}
-	if (count >= 0) {
-		buffer->needs_read_fill = 0;
-		buffer->count = count;
-	} else {
-		ret = count;
-	}
-	return ret;
-}
-
-/**
- *	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 __user *buf, size_t count, loff_t *ppos)
-{
-	struct sysfs_buffer *buffer = file->private_data;
-	ssize_t retval = 0;
-
-	mutex_lock(&buffer->mutex);
-	if (buffer->needs_read_fill || *ppos == 0) {
-		retval = fill_read_buffer(file->f_path.dentry, buffer);
-		if (retval)
-			goto out;
-	}
-	pr_debug("%s: count = %zd, ppos = %lld, buf = %s\n",
-		 __func__, count, *ppos, buffer->page);
-	retval = simple_read_from_buffer(buf, count, ppos, buffer->page,
-					 buffer->count);
-out:
-	mutex_unlock(&buffer->mutex);
-	return retval;
-}
-
-/**
- *	fill_write_buffer - copy buffer from userspace.
- *	@buffer:	data buffer for file.
- *	@buf:		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 __user *buf, size_t count)
-{
-	int error;
-
-	if (!buffer->page)
-		buffer->page = (char *)get_zeroed_page(GFP_KERNEL);
-	if (!buffer->page)
-		return -ENOMEM;
-
-	if (count >= PAGE_SIZE)
-		count = PAGE_SIZE - 1;
-	error = copy_from_user(buffer->page, buf, count);
-	buffer->needs_read_fill = 1;
-	/* if buf is assumed to contain a string, terminate it by \0,
-	   so e.g. sscanf() can scan the string easily */
-	buffer->page[count] = 0;
-	return error ? -EFAULT : count;
-}
-
-
-/**
- *	flush_write_buffer - push buffer to kobject.
- *	@dentry:	dentry to the attribute
- *	@buffer:	data buffer for file.
- *	@count:		number of bytes
- *
- *	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 dentry *dentry,
-			      struct sysfs_buffer *buffer, size_t count)
-{
-	struct sysfs_dirent *attr_sd = dentry->d_fsdata;
-	struct kobject *kobj = attr_sd->s_parent->s_dir.kobj;
-	const struct sysfs_ops *ops = buffer->ops;
-	int rc;
-
-	/* need attr_sd for attr and ops, its parent for kobj */
-	if (!sysfs_get_active(attr_sd))
-		return -ENODEV;
-
-	rc = ops->store(kobj, attr_sd->s_attr.attr, buffer->page, count);
-
-	sysfs_put_active(attr_sd);
-
-	return rc;
-}
-
-
-/**
- *	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 __user *buf,
-				size_t count, loff_t *ppos)
-{
-	struct sysfs_buffer *buffer = file->private_data;
-	ssize_t len;
-
-	mutex_lock(&buffer->mutex);
-	len = fill_write_buffer(buffer, buf, count);
-	if (len > 0)
-		len = flush_write_buffer(file->f_path.dentry, buffer, len);
-	if (len > 0)
-		*ppos += len;
-	mutex_unlock(&buffer->mutex);
-	return len;
+	seq_commit(sf, count);
+	return 0;
 }
 
-/**
- *	sysfs_get_open_dirent - get or create sysfs_open_dirent
- *	@sd: target sysfs_dirent
- *	@buffer: sysfs_buffer for this instance of open
- *
- *	If @sd->s_attr.open exists, increment its reference count;
- *	otherwise, create one.  @buffer is chained to the buffers
- *	list.
- *
- *	LOCKING:
- *	Kernel thread context (may sleep).
- *
- *	RETURNS:
- *	0 on success, -errno on failure.
- */
-static int sysfs_get_open_dirent(struct sysfs_dirent *sd,
-				 struct sysfs_buffer *buffer)
+static ssize_t sysfs_kf_bin_read(struct kernfs_open_file *of, char *buf,
+				 size_t count, loff_t pos)
 {
-	struct sysfs_open_dirent *od, *new_od = NULL;
+	struct bin_attribute *battr = of->kn->priv;
+	struct kobject *kobj = of->kn->parent->priv;
+	loff_t size = file_inode(of->file)->i_size;
 
- retry:
-	spin_lock_irq(&sysfs_open_dirent_lock);
-
-	if (!sd->s_attr.open && new_od) {
-		sd->s_attr.open = new_od;
-		new_od = NULL;
-	}
-
-	od = sd->s_attr.open;
-	if (od) {
-		atomic_inc(&od->refcnt);
-		list_add_tail(&buffer->list, &od->buffers);
-	}
-
-	spin_unlock_irq(&sysfs_open_dirent_lock);
-
-	if (od) {
-		kfree(new_od);
+	if (!count)
 		return 0;
+
+	if (size) {
+		if (pos > size)
+			return 0;
+		if (pos + count > size)
+			count = size - pos;
 	}
 
-	/* not there, initialize a new one and retry */
-	new_od = kmalloc(sizeof(*new_od), GFP_KERNEL);
-	if (!new_od)
-		return -ENOMEM;
+	if (!battr->read)
+		return -EIO;
 
-	atomic_set(&new_od->refcnt, 0);
-	atomic_set(&new_od->event, 1);
-	init_waitqueue_head(&new_od->poll);
-	INIT_LIST_HEAD(&new_od->buffers);
-	goto retry;
+	return battr->read(of->file, kobj, battr, buf, pos, count);
 }
 
-/**
- *	sysfs_put_open_dirent - put sysfs_open_dirent
- *	@sd: target sysfs_dirent
- *	@buffer: associated sysfs_buffer
- *
- *	Put @sd->s_attr.open and unlink @buffer from the buffers list.
- *	If reference count reaches zero, disassociate and free it.
- *
- *	LOCKING:
- *	None.
- */
-static void sysfs_put_open_dirent(struct sysfs_dirent *sd,
-				  struct sysfs_buffer *buffer)
+/* kernfs write callback for regular sysfs files */
+static ssize_t sysfs_kf_write(struct kernfs_open_file *of, char *buf,
+			      size_t count, loff_t pos)
 {
-	struct sysfs_open_dirent *od = sd->s_attr.open;
-	unsigned long flags;
+	const struct sysfs_ops *ops = sysfs_file_ops(of->kn);
+	struct kobject *kobj = of->kn->parent->priv;
 
-	spin_lock_irqsave(&sysfs_open_dirent_lock, flags);
-
-	list_del(&buffer->list);
-	if (atomic_dec_and_test(&od->refcnt))
-		sd->s_attr.open = NULL;
-	else
-		od = NULL;
-
-	spin_unlock_irqrestore(&sysfs_open_dirent_lock, flags);
+	if (!count)
+		return 0;
 
-	kfree(od);
+	return ops->store(kobj, of->kn->priv, buf, count);
 }
 
-static int sysfs_open_file(struct inode *inode, struct file *file)
+/* kernfs write callback for bin sysfs files */
+static ssize_t sysfs_kf_bin_write(struct kernfs_open_file *of, char *buf,
+				  size_t count, loff_t pos)
 {
-	struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
-	struct kobject *kobj = attr_sd->s_parent->s_dir.kobj;
-	struct sysfs_buffer *buffer;
-	const struct sysfs_ops *ops;
-	int error = -EACCES;
-
-	/* need attr_sd for attr and ops, its parent for kobj */
-	if (!sysfs_get_active(attr_sd))
-		return -ENODEV;
-
-	/* every kobject with an attribute needs a ktype assigned */
-	if (kobj->ktype && kobj->ktype->sysfs_ops)
-		ops = kobj->ktype->sysfs_ops;
-	else {
-		WARN(1, KERN_ERR
-		     "missing sysfs attribute operations for kobject: %s\n",
-		     kobject_name(kobj));
-		goto err_out;
-	}
-
-	/* 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 err_out;
-	}
-
-	/* 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 err_out;
+	struct bin_attribute *battr = of->kn->priv;
+	struct kobject *kobj = of->kn->parent->priv;
+	loff_t size = file_inode(of->file)->i_size;
+
+	if (size) {
+		if (size <= pos)
+			return 0;
+		count = min_t(ssize_t, count, size - pos);
 	}
+	if (!count)
+		return 0;
 
-	/* No error? Great, allocate a buffer for the file, and store it
-	 * it in file->private_data for easy access.
-	 */
-	error = -ENOMEM;
-	buffer = kzalloc(sizeof(struct sysfs_buffer), GFP_KERNEL);
-	if (!buffer)
-		goto err_out;
-
-	mutex_init(&buffer->mutex);
-	buffer->needs_read_fill = 1;
-	buffer->ops = ops;
-	file->private_data = buffer;
-
-	/* make sure we have open dirent struct */
-	error = sysfs_get_open_dirent(attr_sd, buffer);
-	if (error)
-		goto err_free;
-
-	/* open succeeded, put active references */
-	sysfs_put_active(attr_sd);
-	return 0;
+	if (!battr->write)
+		return -EIO;
 
- err_free:
-	kfree(buffer);
- err_out:
-	sysfs_put_active(attr_sd);
-	return error;
+	return battr->write(of->file, kobj, battr, buf, pos, count);
 }
 
-static int sysfs_release(struct inode *inode, struct file *filp)
+static int sysfs_kf_bin_mmap(struct kernfs_open_file *of,
+			     struct vm_area_struct *vma)
 {
-	struct sysfs_dirent *sd = filp->f_path.dentry->d_fsdata;
-	struct sysfs_buffer *buffer = filp->private_data;
-
-	sysfs_put_open_dirent(sd, buffer);
-
-	if (buffer->page)
-		free_page((unsigned long)buffer->page);
-	kfree(buffer);
+	struct bin_attribute *battr = of->kn->priv;
+	struct kobject *kobj = of->kn->parent->priv;
 
-	return 0;
+	return battr->mmap(of->file, kobj, battr, vma);
 }
 
-/* Sysfs attribute files are pollable.  The idea is that you read
- * the content and then you use 'poll' or 'select' to wait for
- * the content to change.  When the content changes (assuming the
- * manager for the kobject supports notification), poll will
- * return POLLERR|POLLPRI, and select will return the fd whether
- * it is waiting for read, write, or exceptions.
- * Once poll/select indicates that the value has changed, you
- * need to close and re-open the file, or seek to 0 and read again.
- * Reminder: this only works for attributes which actively support
- * it, and it is not possible to test an attribute from userspace
- * to see if it supports poll (Neither 'poll' nor 'select' return
- * an appropriate error code).  When in doubt, set a suitable timeout value.
- */
-static unsigned int sysfs_poll(struct file *filp, poll_table *wait)
+void sysfs_notify(struct kobject *kobj, const char *dir, const char *attr)
 {
-	struct sysfs_buffer *buffer = filp->private_data;
-	struct sysfs_dirent *attr_sd = filp->f_path.dentry->d_fsdata;
-	struct sysfs_open_dirent *od = attr_sd->s_attr.open;
-
-	/* need parent for the kobj, grab both */
-	if (!sysfs_get_active(attr_sd))
-		goto trigger;
-
-	poll_wait(filp, &od->poll, wait);
-
-	sysfs_put_active(attr_sd);
+	struct kernfs_node *kn = kobj->sd, *tmp;
 
-	if (buffer->event != atomic_read(&od->event))
-		goto trigger;
+	if (kn && dir)
+		kn = kernfs_find_and_get(kn, dir);
+	else
+		kernfs_get(kn);
 
-	return DEFAULT_POLLMASK;
+	if (kn && attr) {
+		tmp = kernfs_find_and_get(kn, attr);
+		kernfs_put(kn);
+		kn = tmp;
+	}
 
- trigger:
-	buffer->needs_read_fill = 1;
-	return DEFAULT_POLLMASK|POLLERR|POLLPRI;
+	if (kn) {
+		kernfs_notify(kn);
+		kernfs_put(kn);
+	}
 }
+EXPORT_SYMBOL_GPL(sysfs_notify);
 
-void sysfs_notify_dirent(struct sysfs_dirent *sd)
-{
-	struct sysfs_open_dirent *od;
-	unsigned long flags;
-
-	spin_lock_irqsave(&sysfs_open_dirent_lock, flags);
+static const struct kernfs_ops sysfs_file_kfops_empty = {
+};
 
-	if (!WARN_ON(sysfs_type(sd) != SYSFS_KOBJ_ATTR)) {
-		od = sd->s_attr.open;
-		if (od) {
-			atomic_inc(&od->event);
-			wake_up_interruptible(&od->poll);
-		}
-	}
+static const struct kernfs_ops sysfs_file_kfops_ro = {
+	.seq_show	= sysfs_kf_seq_show,
+};
 
-	spin_unlock_irqrestore(&sysfs_open_dirent_lock, flags);
-}
-EXPORT_SYMBOL_GPL(sysfs_notify_dirent);
+static const struct kernfs_ops sysfs_file_kfops_wo = {
+	.write		= sysfs_kf_write,
+};
 
-void sysfs_notify(struct kobject *k, const char *dir, const char *attr)
-{
-	struct sysfs_dirent *sd = k->sd;
+static const struct kernfs_ops sysfs_file_kfops_rw = {
+	.seq_show	= sysfs_kf_seq_show,
+	.write		= sysfs_kf_write,
+};
 
-	mutex_lock(&sysfs_mutex);
+static const struct kernfs_ops sysfs_bin_kfops_ro = {
+	.read		= sysfs_kf_bin_read,
+};
 
-	if (sd && dir)
-		sd = sysfs_find_dirent(sd, NULL, dir);
-	if (sd && attr)
-		sd = sysfs_find_dirent(sd, NULL, attr);
-	if (sd)
-		sysfs_notify_dirent(sd);
+static const struct kernfs_ops sysfs_bin_kfops_wo = {
+	.write		= sysfs_kf_bin_write,
+};
 
-	mutex_unlock(&sysfs_mutex);
-}
-EXPORT_SYMBOL_GPL(sysfs_notify);
+static const struct kernfs_ops sysfs_bin_kfops_rw = {
+	.read		= sysfs_kf_bin_read,
+	.write		= sysfs_kf_bin_write,
+};
 
-const 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,
-	.poll		= sysfs_poll,
+static const struct kernfs_ops sysfs_bin_kfops_mmap = {
+	.read		= sysfs_kf_bin_read,
+	.write		= sysfs_kf_bin_write,
+	.mmap		= sysfs_kf_bin_mmap,
 };
 
-static int sysfs_attr_ns(struct kobject *kobj, const struct attribute *attr,
-			 const void **pns)
+int sysfs_add_file_mode_ns(struct kernfs_node *parent,
+			   const struct attribute *attr, bool is_bin,
+			   umode_t mode, const void *ns)
 {
-	struct sysfs_dirent *dir_sd = kobj->sd;
-	const struct sysfs_ops *ops;
-	const void *ns = NULL;
-	int err;
-
-	if (!dir_sd) {
-		WARN(1, KERN_ERR "sysfs: kobject %s without dirent\n",
-			kobject_name(kobj));
-		return -ENOENT;
+	struct lock_class_key *key = NULL;
+	const struct kernfs_ops *ops;
+	struct kernfs_node *kn;
+	loff_t size;
+
+	if (!is_bin) {
+		struct kobject *kobj = parent->priv;
+		const struct sysfs_ops *sysfs_ops = kobj->ktype->sysfs_ops;
+
+		/* every kobject with an attribute needs a ktype assigned */
+		if (WARN(!sysfs_ops, KERN_ERR
+			 "missing sysfs attribute operations for kobject: %s\n",
+			 kobject_name(kobj)))
+			return -EINVAL;
+
+		if (sysfs_ops->show && sysfs_ops->store)
+			ops = &sysfs_file_kfops_rw;
+		else if (sysfs_ops->show)
+			ops = &sysfs_file_kfops_ro;
+		else if (sysfs_ops->store)
+			ops = &sysfs_file_kfops_wo;
+		else
+			ops = &sysfs_file_kfops_empty;
+
+		size = PAGE_SIZE;
+	} else {
+		struct bin_attribute *battr = (void *)attr;
+
+		if (battr->mmap)
+			ops = &sysfs_bin_kfops_mmap;
+		else if (battr->read && battr->write)
+			ops = &sysfs_bin_kfops_rw;
+		else if (battr->read)
+			ops = &sysfs_bin_kfops_ro;
+		else if (battr->write)
+			ops = &sysfs_bin_kfops_wo;
+		else
+			ops = &sysfs_file_kfops_empty;
+
+		size = battr->size;
 	}
 
-	err = 0;
-	if (!sysfs_ns_type(dir_sd))
-		goto out;
-
-	err = -EINVAL;
-	if (!kobj->ktype)
-		goto out;
-	ops = kobj->ktype->sysfs_ops;
-	if (!ops)
-		goto out;
-	if (!ops->namespace)
-		goto out;
-
-	err = 0;
-	ns = ops->namespace(kobj, attr);
-out:
-	if (err) {
-		WARN(1, KERN_ERR
-		     "missing sysfs namespace attribute operation for kobject: %s\n",
-		     kobject_name(kobj));
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+	if (!attr->ignore_lockdep)
+		key = attr->key ?: (struct lock_class_key *)&attr->skey;
+#endif
+	kn = __kernfs_create_file(parent, attr->name, mode, size, ops,
+				  (void *)attr, ns, true, key);
+	if (IS_ERR(kn)) {
+		if (PTR_ERR(kn) == -EEXIST)
+			sysfs_warn_dup(parent, attr->name);
+		return PTR_ERR(kn);
 	}
-	*pns = ns;
-	return err;
-}
-
-int sysfs_add_file_mode(struct sysfs_dirent *dir_sd,
-			const struct attribute *attr, int type, umode_t amode)
-{
-	umode_t mode = (amode & S_IALLUGO) | S_IFREG;
-	struct sysfs_addrm_cxt acxt;
-	struct sysfs_dirent *sd;
-	const void *ns;
-	int rc;
-
-	rc = sysfs_attr_ns(dir_sd->s_dir.kobj, attr, &ns);
-	if (rc)
-		return rc;
-
-	sd = sysfs_new_dirent(attr->name, mode, type);
-	if (!sd)
-		return -ENOMEM;
-
-	sd->s_ns = ns;
-	sd->s_attr.attr = (void *)attr;
-	sysfs_dirent_init_lockdep(sd);
-
-	sysfs_addrm_start(&acxt, dir_sd);
-	rc = sysfs_add_one(&acxt, sd);
-	sysfs_addrm_finish(&acxt);
-
-	if (rc)
-		sysfs_put(sd);
-
-	return rc;
+	return 0;
 }
 
-
-int sysfs_add_file(struct sysfs_dirent *dir_sd, const struct attribute *attr,
-		   int type)
+int sysfs_add_file(struct kernfs_node *parent, const struct attribute *attr,
+		   bool is_bin)
 {
-	return sysfs_add_file_mode(dir_sd, attr, type, attr->mode);
+	return sysfs_add_file_mode_ns(parent, attr, is_bin, attr->mode, NULL);
 }
 
-
 /**
- *	sysfs_create_file - create an attribute file for an object.
- *	@kobj:	object we're creating for.
- *	@attr:	attribute descriptor.
+ * sysfs_create_file_ns - create an attribute file for an object with custom ns
+ * @kobj: object we're creating for
+ * @attr: attribute descriptor
+ * @ns: namespace the new file should belong to
  */
-int sysfs_create_file(struct kobject *kobj, const struct attribute *attr)
+int sysfs_create_file_ns(struct kobject *kobj, const struct attribute *attr,
+			 const void *ns)
 {
 	BUG_ON(!kobj || !kobj->sd || !attr);
 
-	return sysfs_add_file(kobj->sd, attr, SYSFS_KOBJ_ATTR);
+	return sysfs_add_file_mode_ns(kobj->sd, attr, false, attr->mode, ns);
 
 }
-EXPORT_SYMBOL_GPL(sysfs_create_file);
+EXPORT_SYMBOL_GPL(sysfs_create_file_ns);
 
 int sysfs_create_files(struct kobject *kobj, const struct attribute **ptr)
 {
@@ -600,19 +308,21 @@ EXPORT_SYMBOL_GPL(sysfs_create_files);
 int sysfs_add_file_to_group(struct kobject *kobj,
 		const struct attribute *attr, const char *group)
 {
-	struct sysfs_dirent *dir_sd;
+	struct kernfs_node *parent;
 	int error;
 
-	if (group)
-		dir_sd = sysfs_get_dirent(kobj->sd, NULL, group);
-	else
-		dir_sd = sysfs_get(kobj->sd);
+	if (group) {
+		parent = kernfs_find_and_get(kobj->sd, group);
+	} else {
+		parent = kobj->sd;
+		kernfs_get(parent);
+	}
 
-	if (!dir_sd)
+	if (!parent)
 		return -ENOENT;
 
-	error = sysfs_add_file(dir_sd, attr, SYSFS_KOBJ_ATTR);
-	sysfs_put(dir_sd);
+	error = sysfs_add_file(parent, attr, false);
+	kernfs_put(parent);
 
 	return error;
 }
@@ -628,49 +338,63 @@ EXPORT_SYMBOL_GPL(sysfs_add_file_to_group);
 int sysfs_chmod_file(struct kobject *kobj, const struct attribute *attr,
 		     umode_t mode)
 {
-	struct sysfs_dirent *sd;
+	struct kernfs_node *kn;
 	struct iattr newattrs;
-	const void *ns;
 	int rc;
 
-	rc = sysfs_attr_ns(kobj, attr, &ns);
-	if (rc)
-		return rc;
-
-	mutex_lock(&sysfs_mutex);
-
-	rc = -ENOENT;
-	sd = sysfs_find_dirent(kobj->sd, ns, attr->name);
-	if (!sd)
-		goto out;
+	kn = kernfs_find_and_get(kobj->sd, attr->name);
+	if (!kn)
+		return -ENOENT;
 
-	newattrs.ia_mode = (mode & S_IALLUGO) | (sd->s_mode & ~S_IALLUGO);
+	newattrs.ia_mode = (mode & S_IALLUGO) | (kn->mode & ~S_IALLUGO);
 	newattrs.ia_valid = ATTR_MODE;
-	rc = sysfs_sd_setattr(sd, &newattrs);
 
- out:
-	mutex_unlock(&sysfs_mutex);
+	rc = kernfs_setattr(kn, &newattrs);
+
+	kernfs_put(kn);
 	return rc;
 }
 EXPORT_SYMBOL_GPL(sysfs_chmod_file);
 
 /**
- *	sysfs_remove_file - remove an object attribute.
- *	@kobj:	object we're acting for.
- *	@attr:	attribute descriptor.
+ * sysfs_remove_file_ns - remove an object attribute with a custom ns tag
+ * @kobj: object we're acting for
+ * @attr: attribute descriptor
+ * @ns: namespace tag of the file to remove
+ *
+ * Hash the attribute name and namespace tag and kill the victim.
+ */
+void sysfs_remove_file_ns(struct kobject *kobj, const struct attribute *attr,
+			  const void *ns)
+{
+	struct kernfs_node *parent = kobj->sd;
+
+	kernfs_remove_by_name_ns(parent, attr->name, ns);
+}
+EXPORT_SYMBOL_GPL(sysfs_remove_file_ns);
+
+/**
+ * sysfs_remove_file_self - remove an object attribute from its own method
+ * @kobj: object we're acting for
+ * @attr: attribute descriptor
  *
- *	Hash the attribute name and kill the victim.
+ * See kernfs_remove_self() for details.
  */
-void sysfs_remove_file(struct kobject *kobj, const struct attribute *attr)
+bool sysfs_remove_file_self(struct kobject *kobj, const struct attribute *attr)
 {
-	const void *ns;
+	struct kernfs_node *parent = kobj->sd;
+	struct kernfs_node *kn;
+	bool ret;
+
+	kn = kernfs_find_and_get(parent, attr->name);
+	if (WARN_ON_ONCE(!kn))
+		return false;
 
-	if (sysfs_attr_ns(kobj, attr, &ns))
-		return;
+	ret = kernfs_remove_self(kn);
 
-	sysfs_hash_and_remove(kobj->sd, ns, attr->name);
+	kernfs_put(kn);
+	return ret;
 }
-EXPORT_SYMBOL_GPL(sysfs_remove_file);
 
 void sysfs_remove_files(struct kobject *kobj, const struct attribute **ptr)
 {
@@ -689,107 +413,44 @@ EXPORT_SYMBOL_GPL(sysfs_remove_files);
 void sysfs_remove_file_from_group(struct kobject *kobj,
 		const struct attribute *attr, const char *group)
 {
-	struct sysfs_dirent *dir_sd;
+	struct kernfs_node *parent;
 
-	if (group)
-		dir_sd = sysfs_get_dirent(kobj->sd, NULL, group);
-	else
-		dir_sd = sysfs_get(kobj->sd);
-	if (dir_sd) {
-		sysfs_hash_and_remove(dir_sd, NULL, attr->name);
-		sysfs_put(dir_sd);
+	if (group) {
+		parent = kernfs_find_and_get(kobj->sd, group);
+	} else {
+		parent = kobj->sd;
+		kernfs_get(parent);
+	}
+
+	if (parent) {
+		kernfs_remove_by_name(parent, attr->name);
+		kernfs_put(parent);
 	}
 }
 EXPORT_SYMBOL_GPL(sysfs_remove_file_from_group);
 
-struct sysfs_schedule_callback_struct {
-	struct list_head	workq_list;
-	struct kobject		*kobj;
-	void			(*func)(void *);
-	void			*data;
-	struct module		*owner;
-	struct work_struct	work;
-};
-
-static struct workqueue_struct *sysfs_workqueue;
-static DEFINE_MUTEX(sysfs_workq_mutex);
-static LIST_HEAD(sysfs_workq);
-static void sysfs_schedule_callback_work(struct work_struct *work)
+/**
+ *	sysfs_create_bin_file - create binary file for object.
+ *	@kobj:	object.
+ *	@attr:	attribute descriptor.
+ */
+int sysfs_create_bin_file(struct kobject *kobj,
+			  const struct bin_attribute *attr)
 {
-	struct sysfs_schedule_callback_struct *ss = container_of(work,
-			struct sysfs_schedule_callback_struct, work);
-
-	(ss->func)(ss->data);
-	kobject_put(ss->kobj);
-	module_put(ss->owner);
-	mutex_lock(&sysfs_workq_mutex);
-	list_del(&ss->workq_list);
-	mutex_unlock(&sysfs_workq_mutex);
-	kfree(ss);
+	BUG_ON(!kobj || !kobj->sd || !attr);
+
+	return sysfs_add_file(kobj->sd, &attr->attr, true);
 }
+EXPORT_SYMBOL_GPL(sysfs_create_bin_file);
 
 /**
- * sysfs_schedule_callback - helper to schedule a callback for a kobject
- * @kobj: object we're acting for.
- * @func: callback function to invoke later.
- * @data: argument to pass to @func.
- * @owner: module owning the callback code
- *
- * sysfs attribute methods must not unregister themselves or their parent
- * kobject (which would amount to the same thing).  Attempts to do so will
- * deadlock, since unregistration is mutually exclusive with driver
- * callbacks.
- *
- * Instead methods can call this routine, which will attempt to allocate
- * and schedule a workqueue request to call back @func with @data as its
- * argument in the workqueue's process context.  @kobj will be pinned
- * until @func returns.
- *
- * Returns 0 if the request was submitted, -ENOMEM if storage could not
- * be allocated, -ENODEV if a reference to @owner isn't available,
- * -EAGAIN if a callback has already been scheduled for @kobj.
+ *	sysfs_remove_bin_file - remove binary file for object.
+ *	@kobj:	object.
+ *	@attr:	attribute descriptor.
  */
-int sysfs_schedule_callback(struct kobject *kobj, void (*func)(void *),
-		void *data, struct module *owner)
+void sysfs_remove_bin_file(struct kobject *kobj,
+			   const struct bin_attribute *attr)
 {
-	struct sysfs_schedule_callback_struct *ss, *tmp;
-
-	if (!try_module_get(owner))
-		return -ENODEV;
-
-	mutex_lock(&sysfs_workq_mutex);
-	list_for_each_entry_safe(ss, tmp, &sysfs_workq, workq_list)
-		if (ss->kobj == kobj) {
-			module_put(owner);
-			mutex_unlock(&sysfs_workq_mutex);
-			return -EAGAIN;
-		}
-	mutex_unlock(&sysfs_workq_mutex);
-
-	if (sysfs_workqueue == NULL) {
-		sysfs_workqueue = create_singlethread_workqueue("sysfsd");
-		if (sysfs_workqueue == NULL) {
-			module_put(owner);
-			return -ENOMEM;
-		}
-	}
-
-	ss = kmalloc(sizeof(*ss), GFP_KERNEL);
-	if (!ss) {
-		module_put(owner);
-		return -ENOMEM;
-	}
-	kobject_get(kobj);
-	ss->kobj = kobj;
-	ss->func = func;
-	ss->data = data;
-	ss->owner = owner;
-	INIT_WORK(&ss->work, sysfs_schedule_callback_work);
-	INIT_LIST_HEAD(&ss->workq_list);
-	mutex_lock(&sysfs_workq_mutex);
-	list_add_tail(&ss->workq_list, &sysfs_workq);
-	mutex_unlock(&sysfs_workq_mutex);
-	queue_work(sysfs_workqueue, &ss->work);
-	return 0;
+	kernfs_remove_by_name(kobj->sd, attr->attr.name);
 }
-EXPORT_SYMBOL_GPL(sysfs_schedule_callback);
+EXPORT_SYMBOL_GPL(sysfs_remove_bin_file);