/**
* sysfs_remove_one - remove sysfs_dirent from parent
* @acxt: addrm context to use
* @sd: sysfs_dirent to be removed
*
* Mark @sd removed and drop nlink of parent inode if @sd is a
* directory. @sd is unlinked from the children list.
*
* This function should be called between calls to
* sysfs_addrm_start() and sysfs_addrm_finish() and should be
* passed the same @acxt as passed to sysfs_addrm_start().
*
* LOCKING:
* Determined by sysfs_addrm_start().
*/
static void sysfs_remove_one(struct sysfs_addrm_cxt *acxt,
struct sysfs_dirent *sd)
{
struct sysfs_inode_attrs *ps_iattr;
/*
* Removal can be called multiple times on the same node. Only the
* first invocation is effective and puts the base ref.
*/
if (sd->s_flags & SYSFS_FLAG_REMOVED)
return;
sysfs_unlink_sibling(sd);
/* Update timestamps on the parent */
ps_iattr = sd->s_parent->s_iattr;
if (ps_iattr) {
struct iattr *ps_iattrs = &ps_iattr->ia_iattr;
ps_iattrs->ia_ctime = ps_iattrs->ia_mtime = CURRENT_TIME;
}
sd->s_flags |= SYSFS_FLAG_REMOVED;
sd->u.removed_list = acxt->removed;
acxt->removed = sd;
}
static void remove_dir(struct sysfs_dirent *sd)
{
struct sysfs_addrm_cxt acxt;
sysfs_addrm_start(&acxt, sd->s_parent);
sysfs_unlink_sibling(sd);
sysfs_remove_one(&acxt, sd);
sysfs_addrm_finish(&acxt);
}
static int sysfs_dir_close(struct inode *inode, struct file *file)
{
struct sysfs_dirent * cursor = file->private_data;
mutex_lock(&sysfs_mutex);
sysfs_unlink_sibling(cursor);
mutex_unlock(&sysfs_mutex);
release_sysfs_dirent(cursor);
return 0;
}
int sysfs_rename(struct sysfs_dirent *sd, struct sysfs_dirent *new_parent_sd,
const char *new_name, const void *new_ns)
{
int error;
mutex_lock(&sysfs_mutex);
error = 0;
if ((sd->s_parent == new_parent_sd) && (sd->s_ns == new_ns) &&
(strcmp(sd->s_name, new_name) == 0))
goto out; /* nothing to rename */
error = -EEXIST;
if (sysfs_find_dirent(new_parent_sd, new_name, new_ns))
goto out;
/* rename sysfs_dirent */
if (strcmp(sd->s_name, new_name) != 0) {
error = -ENOMEM;
new_name = kstrdup(new_name, GFP_KERNEL);
if (!new_name)
goto out;
kfree(sd->s_name);
sd->s_name = new_name;
}
/*
* Move to the appropriate place in the appropriate directories rbtree.
*/
sysfs_unlink_sibling(sd);
sysfs_get(new_parent_sd);
sysfs_put(sd->s_parent);
sd->s_ns = new_ns;
sd->s_hash = sysfs_name_hash(sd->s_name, sd->s_ns);
sd->s_parent = new_parent_sd;
sysfs_link_sibling(sd);
error = 0;
out:
mutex_unlock(&sysfs_mutex);
return error;
}
int sysfs_rename(struct sysfs_dirent *sd,
struct sysfs_dirent *new_parent_sd, const char *new_name)
{
const char *dup_name = NULL;
int error;
mutex_lock(&sysfs_mutex);
error = 0;
if ((sd->s_parent == new_parent_sd) &&
(strcmp(sd->s_name, new_name) == 0))
goto out; /* nothing to rename */
error = -EEXIST;
if (sysfs_find_dirent(new_parent_sd, new_name))
goto out;
/* rename sysfs_dirent */
if (strcmp(sd->s_name, new_name) != 0) {
error = -ENOMEM;
new_name = dup_name = kstrdup(new_name, GFP_KERNEL);
if (!new_name)
goto out;
dup_name = sd->s_name;
sd->s_name = new_name;
}
/* Remove from old parent's list and insert into new parent's list. */
if (sd->s_parent != new_parent_sd) {
sysfs_unlink_sibling(sd);
sysfs_get(new_parent_sd);
sysfs_put(sd->s_parent);
sd->s_parent = new_parent_sd;
sysfs_link_sibling(sd);
}
error = 0;
out:
mutex_unlock(&sysfs_mutex);
kfree(dup_name);
return error;
}
/**
* sysfs_remove_one - remove sysfs_dirent from parent
* @acxt: addrm context to use
* @sd: sysfs_dirent to be removed
*
* Mark @sd removed and drop nlink of parent inode if @sd is a
* directory. @sd is unlinked from the children list.
*
* This function should be called between calls to
* sysfs_addrm_start() and sysfs_addrm_finish() and should be
* passed the same @acxt as passed to sysfs_addrm_start().
*
* LOCKING:
* Determined by sysfs_addrm_start().
*/
void sysfs_remove_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd)
{
struct sysfs_inode_attrs *ps_iattr;
BUG_ON(sd->s_flags & SYSFS_FLAG_REMOVED);
sysfs_unlink_sibling(sd);
/* Update timestamps on the parent */
ps_iattr = acxt->parent_sd->s_iattr;
if (ps_iattr) {
struct iattr *ps_iattrs = &ps_iattr->ia_iattr;
ps_iattrs->ia_ctime = ps_iattrs->ia_mtime = CURRENT_TIME;
}
sd->s_flags |= SYSFS_FLAG_REMOVED;
sd->s_sibling = acxt->removed;
acxt->removed = sd;
}
static loff_t sysfs_dir_lseek(struct file * file, loff_t offset, int origin)
{
struct dentry * dentry = file->f_path.dentry;
switch (origin) {
case 1:
offset += file->f_pos;
case 0:
if (offset >= 0)
break;
default:
return -EINVAL;
}
if (offset != file->f_pos) {
mutex_lock(&sysfs_mutex);
file->f_pos = offset;
if (file->f_pos >= 2) {
struct sysfs_dirent *sd = dentry->d_fsdata;
struct sysfs_dirent *cursor = file->private_data;
struct sysfs_dirent **pos;
loff_t n = file->f_pos - 2;
sysfs_unlink_sibling(cursor);
pos = &sd->s_children;
while (n && *pos) {
struct sysfs_dirent *next = *pos;
if (sysfs_type(next))
n--;
pos = &(*pos)->s_sibling;
}
cursor->s_sibling = *pos;
*pos = cursor;
}
mutex_unlock(&sysfs_mutex);
}
return offset;
}
int sysfs_move_dir(struct kobject *kobj, struct kobject *new_parent_kobj)
{
struct sysfs_dirent *sd = kobj->sd;
struct sysfs_dirent *new_parent_sd;
struct dentry *old_parent, *new_parent = NULL;
struct dentry *old_dentry = NULL, *new_dentry = NULL;
int error;
BUG_ON(!sd->s_parent);
new_parent_sd = new_parent_kobj->sd ? new_parent_kobj->sd : &sysfs_root;
/* get dentries */
old_dentry = sysfs_get_dentry(sd);
if (IS_ERR(old_dentry)) {
error = PTR_ERR(old_dentry);
goto out_dput;
}
old_parent = sd->s_parent->s_dentry;
new_parent = sysfs_get_dentry(new_parent_sd);
if (IS_ERR(new_parent)) {
error = PTR_ERR(new_parent);
goto out_dput;
}
if (old_parent->d_inode == new_parent->d_inode) {
error = 0;
goto out_dput; /* nothing to move */
}
again:
mutex_lock(&old_parent->d_inode->i_mutex);
if (!mutex_trylock(&new_parent->d_inode->i_mutex)) {
mutex_unlock(&old_parent->d_inode->i_mutex);
goto again;
}
new_dentry = lookup_one_len(kobj->name, new_parent, strlen(kobj->name));
if (IS_ERR(new_dentry)) {
error = PTR_ERR(new_dentry);
goto out_unlock;
} else
error = 0;
d_add(new_dentry, NULL);
d_move(sd->s_dentry, new_dentry);
dput(new_dentry);
/* Remove from old parent's list and insert into new parent's list. */
mutex_lock(&sysfs_mutex);
sysfs_unlink_sibling(sd);
sysfs_get(new_parent_sd);
sysfs_put(sd->s_parent);
sd->s_parent = new_parent_sd;
sysfs_link_sibling(sd);
mutex_unlock(&sysfs_mutex);
out_unlock:
mutex_unlock(&new_parent->d_inode->i_mutex);
mutex_unlock(&old_parent->d_inode->i_mutex);
out_dput:
dput(new_parent);
dput(old_dentry);
dput(new_dentry);
return error;
}
int sysfs_rename_dir(struct kobject *kobj, struct sysfs_dirent *new_parent_sd,
const char *new_name)
{
struct sysfs_dirent *sd = kobj->sd;
struct dentry *new_parent = NULL;
struct dentry *old_dentry = NULL, *new_dentry = NULL;
const char *dup_name = NULL;
int error;
/* get dentries */
old_dentry = sysfs_get_dentry(sd);
if (IS_ERR(old_dentry)) {
error = PTR_ERR(old_dentry);
goto out_dput;
}
new_parent = sysfs_get_dentry(new_parent_sd);
if (IS_ERR(new_parent)) {
error = PTR_ERR(new_parent);
goto out_dput;
}
/* lock new_parent and get dentry for new name */
mutex_lock(&new_parent->d_inode->i_mutex);
new_dentry = lookup_one_len(new_name, new_parent, strlen(new_name));
if (IS_ERR(new_dentry)) {
error = PTR_ERR(new_dentry);
goto out_unlock;
}
/* By allowing two different directories with the same
* d_parent we allow this routine to move between different
* shadows of the same directory
*/
error = -EINVAL;
if (old_dentry->d_parent->d_inode != new_parent->d_inode ||
new_dentry->d_parent->d_inode != new_parent->d_inode ||
old_dentry == new_dentry)
goto out_unlock;
error = -EEXIST;
if (new_dentry->d_inode)
goto out_unlock;
/* rename kobject and sysfs_dirent */
error = -ENOMEM;
new_name = dup_name = kstrdup(new_name, GFP_KERNEL);
if (!new_name)
goto out_drop;
error = kobject_set_name(kobj, "%s", new_name);
if (error)
goto out_drop;
mutex_lock(&sysfs_mutex);
dup_name = sd->s_name;
sd->s_name = new_name;
/* move under the new parent */
d_add(new_dentry, NULL);
d_move(sd->s_dentry, new_dentry);
sysfs_unlink_sibling(sd);
sysfs_get(new_parent_sd);
sysfs_put(sd->s_parent);
sd->s_parent = new_parent_sd;
sysfs_link_sibling(sd);
mutex_unlock(&sysfs_mutex);
error = 0;
goto out_unlock;
out_drop:
d_drop(new_dentry);
out_unlock:
mutex_unlock(&new_parent->d_inode->i_mutex);
out_dput:
kfree(dup_name);
dput(new_parent);
dput(old_dentry);
dput(new_dentry);
return error;
}
