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: Tejun Heo <htejun@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Tejun Heo 2007-06-14 03:45:16 +09:00 committed by Greg Kroah-Hartman
parent 0ab66088c8
commit 73107cb3ad
4 changed files with 13 additions and 101 deletions

View File

@ -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);

View File

@ -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);

View File

@ -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;

View File

@ -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) {