sysfs: consolidate sysfs_dirent creation functions

Currently there are four functions to create sysfs_dirent -
__sysfs_new_dirent(), sysfs_new_dirent(), __sysfs_make_dirent() and
sysfs_make_dirent().  Other than sysfs_make_dirent(), no function has
two users if calls to implement other functions are excluded.

This patch consolidates sysfs_dirent creation functions into the
following two.

* sysfs_new_dirent() : allocate and initialize
* sysfs_attach_dirent() : attach to sysfs_dirent hierarchy and/or
			  associate with dentry

This simplifies interface and gives callers more flexibility.  This is
in preparation of object reference simplification.

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 03:45:14 +09:00 committed by Greg Kroah-Hartman
parent 996b73764e
commit a26cd7226c
4 changed files with 50 additions and 67 deletions

View File

@ -85,10 +85,7 @@ static struct dentry_operations sysfs_dentry_ops = {
.d_iput = sysfs_d_iput,
};
/*
* Allocates a new sysfs_dirent and links it to the parent sysfs_dirent
*/
static struct sysfs_dirent * __sysfs_new_dirent(void * element)
struct sysfs_dirent *sysfs_new_dirent(void *element, umode_t mode, int type)
{
struct sysfs_dirent * sd;
@ -105,27 +102,27 @@ static struct sysfs_dirent * __sysfs_new_dirent(void * element)
atomic_set(&sd->s_event, 1);
INIT_LIST_HEAD(&sd->s_children);
INIT_LIST_HEAD(&sd->s_sibling);
sd->s_element = element;
sd->s_mode = mode;
sd->s_type = type;
return sd;
}
static void __sysfs_list_dirent(struct sysfs_dirent *parent_sd,
struct sysfs_dirent *sd)
void sysfs_attach_dirent(struct sysfs_dirent *sd,
struct sysfs_dirent *parent_sd, struct dentry *dentry)
{
if (sd)
if (dentry) {
sd->s_dentry = dentry;
dentry->d_fsdata = sysfs_get(sd);
dentry->d_op = &sysfs_dentry_ops;
}
if (parent_sd)
list_add(&sd->s_sibling, &parent_sd->s_children);
}
static struct sysfs_dirent * sysfs_new_dirent(struct sysfs_dirent *parent_sd,
void * element)
{
struct sysfs_dirent *sd;
sd = __sysfs_new_dirent(element);
__sysfs_list_dirent(parent_sd, sd);
return sd;
}
/*
*
* Return -EEXIST if there is already a sysfs element with the same name for
@ -151,39 +148,6 @@ int sysfs_dirent_exist(struct sysfs_dirent *parent_sd,
return 0;
}
static struct sysfs_dirent *
__sysfs_make_dirent(struct dentry *dentry, void *element, mode_t mode, int type)
{
struct sysfs_dirent * sd;
sd = __sysfs_new_dirent(element);
if (!sd)
goto out;
sd->s_mode = mode;
sd->s_type = type;
sd->s_dentry = dentry;
if (dentry) {
dentry->d_fsdata = sysfs_get(sd);
dentry->d_op = &sysfs_dentry_ops;
}
out:
return sd;
}
int sysfs_make_dirent(struct sysfs_dirent * parent_sd, struct dentry * dentry,
void * element, umode_t mode, int type)
{
struct sysfs_dirent *sd;
sd = __sysfs_make_dirent(dentry, element, mode, type);
__sysfs_list_dirent(parent_sd, sd);
return sd ? 0 : -ENOMEM;
}
static int init_dir(struct inode * inode)
{
inode->i_op = &sysfs_dir_inode_operations;
@ -227,10 +191,11 @@ static int create_dir(struct kobject *kobj, struct dentry *parent,
if (sysfs_dirent_exist(parent->d_fsdata, name))
goto out_dput;
error = sysfs_make_dirent(parent->d_fsdata, dentry, kobj, mode,
SYSFS_DIR);
if (error)
error = -ENOMEM;
sd = sysfs_new_dirent(kobj, mode, SYSFS_DIR);
if (!sd)
goto out_drop;
sysfs_attach_dirent(sd, parent->d_fsdata, dentry);
error = sysfs_create(dentry, mode, init_dir);
if (error)
@ -245,7 +210,6 @@ static int create_dir(struct kobject *kobj, struct dentry *parent,
goto out_dput;
out_sput:
sd = dentry->d_fsdata;
list_del_init(&sd->s_sibling);
sysfs_put(sd);
out_drop:
@ -557,13 +521,16 @@ static int sysfs_dir_open(struct inode *inode, struct file *file)
{
struct dentry * dentry = file->f_path.dentry;
struct sysfs_dirent * parent_sd = dentry->d_fsdata;
struct sysfs_dirent * sd;
mutex_lock(&dentry->d_inode->i_mutex);
file->private_data = sysfs_new_dirent(parent_sd, NULL);
sd = sysfs_new_dirent(NULL, 0, 0);
if (sd)
sysfs_attach_dirent(sd, parent_sd, NULL);
mutex_unlock(&dentry->d_inode->i_mutex);
return file->private_data ? 0 : -ENOMEM;
file->private_data = sd;
return sd ? 0 : -ENOMEM;
}
static int sysfs_dir_close(struct inode *inode, struct file *file)
@ -736,9 +703,10 @@ struct dentry *sysfs_create_shadow_dir(struct kobject *kobj)
if (!shadow)
goto nomem;
sd = __sysfs_make_dirent(shadow, kobj, inode->i_mode, SYSFS_DIR);
sd = sysfs_new_dirent(kobj, inode->i_mode, SYSFS_DIR);
if (!sd)
goto nomem;
sysfs_attach_dirent(sd, NULL, shadow);
d_instantiate(shadow, igrab(inode));
inc_nlink(inode);

View File

@ -444,14 +444,25 @@ int sysfs_add_file(struct dentry * dir, const struct attribute * attr, int type)
{
struct sysfs_dirent * parent_sd = dir->d_fsdata;
umode_t mode = (attr->mode & S_IALLUGO) | S_IFREG;
int error = -EEXIST;
struct sysfs_dirent *sd;
int error = 0;
mutex_lock(&dir->d_inode->i_mutex);
if (!sysfs_dirent_exist(parent_sd, attr->name))
error = sysfs_make_dirent(parent_sd, NULL, (void *)attr,
mode, type);
mutex_unlock(&dir->d_inode->i_mutex);
if (sysfs_dirent_exist(parent_sd, attr->name)) {
error = -EEXIST;
goto out_unlock;
}
sd = sysfs_new_dirent((void *)attr, mode, type);
if (!sd) {
error = -ENOMEM;
goto out_unlock;
}
sysfs_attach_dirent(sd, parent_sd, NULL);
out_unlock:
mutex_unlock(&dir->d_inode->i_mutex);
return error;
}

View File

@ -49,6 +49,7 @@ static int sysfs_add_link(struct dentry * parent, const char * name, struct kobj
{
struct sysfs_dirent * parent_sd = parent->d_fsdata;
struct sysfs_symlink * sl;
struct sysfs_dirent * sd;
int error;
error = -ENOMEM;
@ -63,10 +64,10 @@ static int sysfs_add_link(struct dentry * parent, const char * name, struct kobj
strcpy(sl->link_name, name);
sl->target_kobj = kobject_get(target);
error = sysfs_make_dirent(parent_sd, NULL, sl, S_IFLNK|S_IRWXUGO,
SYSFS_KOBJ_LINK);
if (error)
sd = sysfs_new_dirent(sl, S_IFLNK|S_IRWXUGO, SYSFS_KOBJ_LINK);
if (!sd)
goto err_out;
sysfs_attach_dirent(sd, parent_sd, NULL);
return 0;

View File

@ -20,8 +20,11 @@ extern int sysfs_create(struct dentry *, int mode, int (*init)(struct inode *));
extern void release_sysfs_dirent(struct sysfs_dirent * sd);
extern int sysfs_dirent_exist(struct sysfs_dirent *, const unsigned char *);
extern int sysfs_make_dirent(struct sysfs_dirent *, struct dentry *, void *,
umode_t, int);
extern struct sysfs_dirent *sysfs_new_dirent(void *element, umode_t mode,
int type);
extern void sysfs_attach_dirent(struct sysfs_dirent *sd,
struct sysfs_dirent *parent_sd,
struct dentry *dentry);
extern int sysfs_add_file(struct dentry *, const struct attribute *, int);
extern int sysfs_hash_and_remove(struct dentry * dir, const char * name);