static int sysfs_fill_super(struct super_block *sb, void *data, int silent)
{
struct inode *inode;
struct dentry *root;
sb->s_blocksize = PAGE_CACHE_SIZE;
sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
sb->s_magic = SYSFS_MAGIC;
sb->s_op = &sysfs_ops;
sb->s_time_gran = 1;
/* get root inode, initialize and unlock it */
mutex_lock(&sysfs_mutex);
inode = sysfs_get_inode(sb, &sysfs_root);
mutex_unlock(&sysfs_mutex);
if (!inode) {
pr_debug("sysfs: could not get root inode\n");
return -ENOMEM;
}
/* instantiate and link root dentry */
root = d_alloc_root(inode);
if (!root) {
pr_debug("%s: could not get root dentry!\n",__func__);
iput(inode);
return -ENOMEM;
}
root->d_fsdata = &sysfs_root;
sb->s_root = root;
return 0;
}
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;
}
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 bin_attribute *bin_attr;
struct inode *inode;
int found = 0;
mutex_lock(&sysfs_mutex);
for (sd = parent_sd->s_children; sd; sd = sd->s_sibling) {
if (sysfs_type(sd) &&
!strcmp(sd->s_name, dentry->d_name.name)) {
found = 1;
break;
}
}
/* no such entry */
if (!found)
goto out_unlock;
/* attach dentry and inode */
inode = sysfs_get_inode(sd);
if (!inode) {
ret = ERR_PTR(-ENOMEM);
goto out_unlock;
}
if (inode->i_state & I_NEW) {
/* initialize inode according to type */
switch (sysfs_type(sd)) {
case SYSFS_DIR:
inode->i_op = &sysfs_dir_inode_operations;
inode->i_fop = &sysfs_dir_operations;
inode->i_nlink = sysfs_count_nlink(sd);
break;
case SYSFS_KOBJ_ATTR:
inode->i_size = PAGE_SIZE;
inode->i_fop = &sysfs_file_operations;
break;
case SYSFS_KOBJ_BIN_ATTR:
bin_attr = sd->s_elem.bin_attr.bin_attr;
inode->i_size = bin_attr->size;
inode->i_fop = &bin_fops;
break;
case SYSFS_KOBJ_LINK:
inode->i_op = &sysfs_symlink_inode_operations;
break;
default:
BUG();
}
}
sysfs_instantiate(dentry, inode);
sysfs_attach_dentry(sd, dentry);
out_unlock:
mutex_unlock(&sysfs_mutex);
return ret;
}