Commit 73107cb3 authored by Tejun Heo's avatar Tejun Heo Committed by Greg Kroah-Hartman
Browse files

sysfs: kill attribute file orphaning 



Now that sysfs_dirent can be disconnected from kobject on deletion,
there is no need to orphan each attribute files.  All [bin_]attribute
nodes are automatically orphaned when the parent node is deleted.
Kill attribute file orphaning.

Signed-off-by: default avatarTejun Heo <htejun@gmail.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent 0ab66088

fs/sysfs/file.c

+13 −52
Original line number Diff line number Diff line
@@ -50,29 +50,15 @@ static struct sysfs_ops subsys_sysfs_ops = { 
	.store	= subsys_attr_store,

};



/**

 *	add_to_collection - add buffer to a collection

 *	@buffer:	buffer to be added

 *	@node:		inode of set to add to

 */



static inline void

add_to_collection(struct sysfs_buffer *buffer, struct inode *node)

{

	struct sysfs_buffer_collection *set = node->i_private;



	mutex_lock(&node->i_mutex);

	list_add(&buffer->associates, &set->associates);

	mutex_unlock(&node->i_mutex);

}



static inline void

remove_from_collection(struct sysfs_buffer *buffer, struct inode *node)

{

	mutex_lock(&node->i_mutex);

	list_del(&buffer->associates);

	mutex_unlock(&node->i_mutex);

}

struct sysfs_buffer {

	size_t			count;

	loff_t			pos;

	char			* page;

	struct sysfs_ops	* ops;

	struct semaphore	sem;

	int			needs_read_fill;

	int			event;

};



/**

 *	fill_read_buffer - allocate and fill buffer from object.
@@ -144,9 +130,6 @@ sysfs_read_file(struct file *file, char __user *buf, size_t count, loff_t *ppos) 


	down(&buffer->sem);

	if (buffer->needs_read_fill) {

		if (buffer->orphaned)

			retval = -ENODEV;

		else

		retval = fill_read_buffer(file->f_path.dentry,buffer);

		if (retval)

			goto out;
@@ -246,16 +229,11 @@ sysfs_write_file(struct file *file, const char __user *buf, size_t count, loff_t 
	ssize_t len;



	down(&buffer->sem);

	if (buffer->orphaned) {

		len = -ENODEV;

		goto out;

	}

	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;

out:

	up(&buffer->sem);

	return len;

}
@@ -265,7 +243,6 @@ static int sysfs_open_file(struct inode *inode, struct file *file) 
	struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;

	struct attribute *attr = attr_sd->s_elem.attr.attr;

	struct kobject *kobj = attr_sd->s_parent->s_elem.dir.kobj;

	struct sysfs_buffer_collection *set;

	struct sysfs_buffer * buffer;

	struct sysfs_ops * ops = NULL;

	int error;
@@ -289,26 +266,14 @@ static int sysfs_open_file(struct inode *inode, struct file *file) 
	else

		ops = &subsys_sysfs_ops;



	error = -EACCES;



	/* No sysfs operations, either from having no subsystem,

	 * or the subsystem have no operations.

	 */

	error = -EACCES;

	if (!ops)

		goto err_mput;



	/* make sure we have a collection to add our buffers to */

	mutex_lock(&inode->i_mutex);

	if (!(set = inode->i_private)) {

		error = -ENOMEM;

		if (!(set = inode->i_private = kmalloc(sizeof(struct sysfs_buffer_collection), GFP_KERNEL)))

			goto err_mput;

		else

			INIT_LIST_HEAD(&set->associates);

	}

	mutex_unlock(&inode->i_mutex);



	error = -EACCES;



	/* File needs write support.

	 * The inode's perms must say it's ok, 

	 * and we must have a store method.
@@ -335,11 +300,9 @@ static int sysfs_open_file(struct inode *inode, struct file *file) 
	if (!buffer)

		goto err_mput;



	INIT_LIST_HEAD(&buffer->associates);

	init_MUTEX(&buffer->sem);

	buffer->needs_read_fill = 1;

	buffer->ops = ops;

	add_to_collection(buffer, inode);

	file->private_data = buffer;



	/* open succeeded, put active references and pin attr_sd */
@@ -360,8 +323,6 @@ static int sysfs_release(struct inode * inode, struct file * filp) 
	struct attribute *attr = attr_sd->s_elem.attr.attr;

	struct sysfs_buffer *buffer = filp->private_data;



	if (buffer)

		remove_from_collection(buffer, inode);

	sysfs_put(attr_sd);

	/* After this point, attr should not be accessed. */

	module_put(attr->owner);

fs/sysfs/inode.c

+0 −25
Original line number Diff line number Diff line
@@ -191,24 +191,6 @@ int sysfs_create(struct dentry * dentry, int mode, int (*init)(struct inode *)) 
	return error;

}



static inline void orphan_all_buffers(struct inode *node)

{

	struct sysfs_buffer_collection *set;

	struct sysfs_buffer *buf;



	mutex_lock_nested(&node->i_mutex, I_MUTEX_CHILD);

	set = node->i_private;

	if (set) {

		list_for_each_entry(buf, &set->associates, associates) {

			down(&buf->sem);

			buf->orphaned = 1;

			up(&buf->sem);

		}

	}

	mutex_unlock(&node->i_mutex);

}





/*

 * Unhashes the dentry corresponding to given sysfs_dirent

 * Called with parent inode's i_mutex held.
@@ -216,7 +198,6 @@ static inline void orphan_all_buffers(struct inode *node) 
void sysfs_drop_dentry(struct sysfs_dirent * sd, struct dentry * parent)

{

	struct dentry *dentry = NULL;

	struct inode *inode;



	/* We're not holding a reference to ->s_dentry dentry but the

	 * field will stay valid as long as sysfs_lock is held.
@@ -236,17 +217,11 @@ void sysfs_drop_dentry(struct sysfs_dirent * sd, struct dentry * parent) 
		spin_lock(&dcache_lock);

		spin_lock(&dentry->d_lock);

		if (!d_unhashed(dentry) && dentry->d_inode) {

			inode = dentry->d_inode;

			spin_lock(&inode->i_lock);

			__iget(inode);

			spin_unlock(&inode->i_lock);

			dget_locked(dentry);

			__d_drop(dentry);

			spin_unlock(&dentry->d_lock);

			spin_unlock(&dcache_lock);

			simple_unlink(parent->d_inode, dentry);

			orphan_all_buffers(inode);

			iput(inode);

		} else {

			spin_unlock(&dentry->d_lock);

			spin_unlock(&dcache_lock);

fs/sysfs/mount.c

+0 −8
Original line number Diff line number Diff line
@@ -19,12 +19,9 @@ struct vfsmount *sysfs_mount; 
struct super_block * sysfs_sb = NULL;

struct kmem_cache *sysfs_dir_cachep;



static void sysfs_clear_inode(struct inode *inode);



static const struct super_operations sysfs_ops = {

	.statfs		= simple_statfs,

	.drop_inode	= sysfs_delete_inode,

	.clear_inode	= sysfs_clear_inode,

};



static struct sysfs_dirent sysfs_root = {
@@ -36,11 +33,6 @@ static struct sysfs_dirent sysfs_root = { 
	.s_ino		= 1,

};



static void sysfs_clear_inode(struct inode *inode)

{

	kfree(inode->i_private);

}



static int sysfs_fill_super(struct super_block *sb, void *data, int silent)

{

	struct inode *inode;

fs/sysfs/sysfs.h

+0 −16
Original line number Diff line number Diff line
@@ -88,22 +88,6 @@ extern const struct file_operations bin_fops; 
extern const struct inode_operations sysfs_dir_inode_operations;

extern const struct inode_operations sysfs_symlink_inode_operations;



struct sysfs_buffer {

	struct list_head		associates;

	size_t				count;

	loff_t				pos;

	char				* page;

	struct sysfs_ops		* ops;

	struct semaphore		sem;

	int				orphaned;

	int				needs_read_fill;

	int				event;

};



struct sysfs_buffer_collection {

	struct list_head	associates;

};



static inline struct sysfs_dirent * sysfs_get(struct sysfs_dirent * sd)

{

	if (sd) {

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