void sysfs_notify(struct kobject *k, char *dir, char *attr)
{
struct sysfs_dirent *sd = k->sd;
mutex_lock(&sysfs_mutex);
if (sd && dir)
sd = sysfs_find_dirent(sd, dir);
if (sd && attr)
sd = sysfs_find_dirent(sd, attr);
if (sd) {
struct sysfs_open_dirent *od;
spin_lock(&sysfs_open_dirent_lock);
od = sd->s_attr.open;
if (od) {
atomic_inc(&od->event);
wake_up_interruptible(&od->poll);
}
spin_unlock(&sysfs_open_dirent_lock);
}
mutex_unlock(&sysfs_mutex);
}
void sysfs_notify(struct kobject *k, const char *dir, const char *attr)
{
struct sysfs_dirent *sd = k->sd;
mutex_lock(&sysfs_mutex);
if (sd && dir)
sd = sysfs_find_dirent(sd, dir);
if (sd && attr)
sd = sysfs_find_dirent(sd, attr);
if (sd)
sysfs_notify_dirent(sd);
mutex_unlock(&sysfs_mutex);
}
int sysfs_add_file(struct sysfs_dirent *dir_sd, const struct attribute *attr,
int type)
{
umode_t mode = (attr->mode & S_IALLUGO) | S_IFREG;
struct sysfs_addrm_cxt acxt;
struct sysfs_dirent *sd;
sd = sysfs_new_dirent(attr->name, mode, type);
if (!sd)
return -ENOMEM;
sd->s_elem.attr.attr = (void *)attr;
sysfs_addrm_start(&acxt, dir_sd);
if (!sysfs_find_dirent(dir_sd, attr->name)) {
sysfs_add_one(&acxt, sd);
sysfs_link_sibling(sd);
}
if (!sysfs_addrm_finish(&acxt)) {
sysfs_put(sd);
return -EEXIST;
}
return 0;
}
static int create_dir(struct kobject *kobj, struct sysfs_dirent *parent_sd,
const char *name, struct sysfs_dirent **p_sd)
{
umode_t mode = S_IFDIR| S_IRWXU | S_IRUGO | S_IXUGO;
struct sysfs_addrm_cxt acxt;
struct sysfs_dirent *sd;
/* allocate */
sd = sysfs_new_dirent(name, mode, SYSFS_DIR);
if (!sd)
return -ENOMEM;
sd->s_elem.dir.kobj = kobj;
/* link in */
sysfs_addrm_start(&acxt, parent_sd);
if (!sysfs_find_dirent(parent_sd, name)) {
sysfs_add_one(&acxt, sd);
sysfs_link_sibling(sd);
}
if (!sysfs_addrm_finish(&acxt)) {
sysfs_put(sd);
return -EEXIST;
}
*p_sd = sd;
return 0;
}
/**
* sysfs_hash_and_remove - find a sysfs_dirent by name and remove it
* @dir_sd: parent of the target
* @name: name of the sysfs_dirent to remove
* @ns: namespace tag of the sysfs_dirent to remove
*
* Look for the sysfs_dirent with @name and @ns under @dir_sd and remove
* it. Returns 0 on success, -ENOENT if such entry doesn't exist.
*/
int sysfs_hash_and_remove(struct sysfs_dirent *dir_sd, const char *name,
const void *ns)
{
struct sysfs_addrm_cxt acxt;
struct sysfs_dirent *sd;
if (!dir_sd) {
WARN(1, KERN_WARNING "sysfs: can not remove '%s', no directory\n",
name);
return -ENOENT;
}
sysfs_addrm_start(&acxt);
sd = sysfs_find_dirent(dir_sd, name, ns);
if (sd)
__sysfs_remove(&acxt, sd);
sysfs_addrm_finish(&acxt);
if (sd)
return 0;
else
return -ENOENT;
}
void sysfs_notify(struct kobject *k, char *dir, char *attr)
{
struct sysfs_dirent *sd = k->sd;
mutex_lock(&sysfs_mutex);
if (sd && dir)
sd = sysfs_find_dirent(sd, dir);
if (sd && attr)
sd = sysfs_find_dirent(sd, attr);
if (sd) {
atomic_inc(&sd->s_event);
wake_up_interruptible(&k->poll);
}
mutex_unlock(&sysfs_mutex);
}
void sysfs_notify(struct kobject *k, const char *dir, const char *attr)
{
struct sysfs_dirent *sd = k->sd;
mutex_lock(&sysfs_mutex);
if (sd && dir)
/* Only directories are tagged, so no need to pass
* a tag explicitly.
*/
sd = sysfs_find_dirent(sd, NULL, dir);
if (sd && attr)
sd = sysfs_find_dirent(sd, NULL, attr);
if (sd)
sysfs_notify_dirent(sd);
mutex_unlock(&sysfs_mutex);
}
/**
* sysfs_get_dirent - find and get sysfs_dirent with the given name
* @parent_sd: sysfs_dirent to search under
* @name: name to look for
*
* Look for sysfs_dirent with name @name under @parent_sd and get
* it if found.
*
* LOCKING:
* Kernel thread context (may sleep). Grabs sysfs_mutex.
*
* RETURNS:
* Pointer to sysfs_dirent if found, NULL if not.
*/
struct sysfs_dirent *sysfs_get_dirent(struct sysfs_dirent *parent_sd,
const unsigned char *name)
{
struct sysfs_dirent *sd;
mutex_lock(&sysfs_mutex);
sd = sysfs_find_dirent(parent_sd, name);
sysfs_get(sd);
mutex_unlock(&sysfs_mutex);
return sd;
}
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_add_one - add sysfs_dirent to parent without warning
* @acxt: addrm context to use
* @sd: sysfs_dirent to be added
*
* Get @acxt->parent_sd and set sd->s_parent to it and increment
* nlink of parent inode if @sd is a directory and link into the
* children list of the parent.
*
* 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().
*
* RETURNS:
* 0 on success, -EEXIST if entry with the given name already
* exists.
*/
int __sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd)
{
struct sysfs_inode_attrs *ps_iattr;
if (sysfs_find_dirent(acxt->parent_sd, sd->s_name))
return -EEXIST;
sd->s_parent = sysfs_get(acxt->parent_sd);
sysfs_link_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;
}
return 0;
}
int sysfs_hash_and_remove(struct sysfs_dirent *dir_sd, const char *name)
{
struct sysfs_addrm_cxt acxt;
struct sysfs_dirent *sd;
if (!dir_sd)
return -ENOENT;
sysfs_addrm_start(&acxt, dir_sd);
sd = sysfs_find_dirent(dir_sd, name);
if (sd)
sysfs_remove_one(&acxt, sd);
sysfs_addrm_finish(&acxt);
if (sd)
return 0;
else
return -ENOENT;
}
int sysfs_chmod_file(struct kobject *kobj, struct attribute *attr, mode_t mode)
{
struct sysfs_dirent *sd;
struct iattr newattrs;
int rc;
mutex_lock(&sysfs_mutex);
rc = -ENOENT;
sd = sysfs_find_dirent(kobj->sd, NULL, attr->name);
if (!sd)
goto out;
newattrs.ia_mode = (mode & S_IALLUGO) | (sd->s_mode & ~S_IALLUGO);
newattrs.ia_valid = ATTR_MODE;
rc = sysfs_sd_setattr(sd, &newattrs);
out:
mutex_unlock(&sysfs_mutex);
return rc;
}
static struct dentry * sysfs_lookup(struct inode *dir, struct dentry *dentry,
struct nameidata *nd)
{
struct dentry *ret = NULL;
struct sysfs_dirent *parent_sd = dentry->d_parent->d_fsdata;
struct sysfs_dirent *sd;
struct inode *inode;
mutex_lock(&sysfs_mutex);
sd = sysfs_find_dirent(parent_sd, dentry->d_name.name);
/* no such entry */
if (!sd) {
ret = ERR_PTR(-ENOENT);
goto out_unlock;
}
/* attach dentry and inode */
inode = sysfs_get_inode(dir->i_sb, sd);
if (!inode) {
ret = ERR_PTR(-ENOMEM);
goto out_unlock;
}
/* instantiate and hash dentry */
ret = d_find_alias(inode);
if (!ret) {
dentry->d_op = &sysfs_dentry_ops;
dentry->d_fsdata = sysfs_get(sd);
d_add(dentry, inode);
} else {
d_move(ret, dentry);
iput(inode);
}
out_unlock:
mutex_unlock(&sysfs_mutex);
return ret;
}
static struct dentry *sysfs_lookup(struct inode *dir, struct dentry *dentry,
unsigned int flags)
{
struct dentry *ret = NULL;
struct dentry *parent = dentry->d_parent;
struct sysfs_dirent *parent_sd = parent->d_fsdata;
struct sysfs_dirent *sd;
struct inode *inode;
enum kobj_ns_type type;
const void *ns;
mutex_lock(&sysfs_mutex);
type = sysfs_ns_type(parent_sd);
ns = sysfs_info(dir->i_sb)->ns[type];
sd = sysfs_find_dirent(parent_sd, dentry->d_name.name, ns);
/* no such entry */
if (!sd) {
ret = ERR_PTR(-ENOENT);
goto out_unlock;
}
dentry->d_fsdata = sysfs_get(sd);
/* attach dentry and inode */
inode = sysfs_get_inode(dir->i_sb, sd);
if (!inode) {
ret = ERR_PTR(-ENOMEM);
goto out_unlock;
}
/* instantiate and hash dentry */
ret = d_materialise_unique(dentry, inode);
out_unlock:
mutex_unlock(&sysfs_mutex);
return ret;
}
