#include <linux/mount.h>
#include <linux/module.h>
#include <linux/kobject.h>
+#include <linux/namei.h>
#include "sysfs.h"
DECLARE_RWSEM(sysfs_rename_sem);
+static void sysfs_d_iput(struct dentry * dentry, struct inode * inode)
+{
+ struct sysfs_dirent * sd = dentry->d_fsdata;
+
+ if (sd) {
+ BUG_ON(sd->s_dentry != dentry);
+ sd->s_dentry = NULL;
+ sysfs_put(sd);
+ }
+ iput(inode);
+}
+
+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(struct sysfs_dirent * parent_sd,
+ void * element)
+{
+ struct sysfs_dirent * sd;
+
+ sd = kmem_cache_alloc(sysfs_dir_cachep, GFP_KERNEL);
+ if (!sd)
+ return NULL;
+
+ memset(sd, 0, sizeof(*sd));
+ atomic_set(&sd->s_count, 1);
+ atomic_set(&sd->s_event, 1);
+ INIT_LIST_HEAD(&sd->s_children);
+ list_add(&sd->s_sibling, &parent_sd->s_children);
+ sd->s_element = element;
+
+ return sd;
+}
+
+/*
+ *
+ * Return -EEXIST if there is already a sysfs element with the same name for
+ * the same parent.
+ *
+ * called with parent inode's i_mutex held
+ */
+int sysfs_dirent_exist(struct sysfs_dirent *parent_sd,
+ const unsigned char *new)
+{
+ struct sysfs_dirent * sd;
+
+ list_for_each_entry(sd, &parent_sd->s_children, s_sibling) {
+ if (sd->s_element) {
+ const unsigned char *existing = sysfs_get_name(sd);
+ if (strcmp(existing, new))
+ continue;
+ else
+ return -EEXIST;
+ }
+ }
+
+ return 0;
+}
+
+
+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_new_dirent(parent_sd, element);
+ if (!sd)
+ return -ENOMEM;
+
+ 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;
+ }
+
+ return 0;
+}
+
static int init_dir(struct inode * inode)
{
- inode->i_op = &simple_dir_inode_operations;
- inode->i_fop = &simple_dir_operations;
+ inode->i_op = &sysfs_dir_inode_operations;
+ inode->i_fop = &sysfs_dir_operations;
/* directory inodes start off with i_nlink == 2 (for "." entry) */
- inode->i_nlink++;
+ inc_nlink(inode);
+ return 0;
+}
+
+static int init_file(struct inode * inode)
+{
+ inode->i_size = PAGE_SIZE;
+ inode->i_fop = &sysfs_file_operations;
return 0;
}
+static int init_symlink(struct inode * inode)
+{
+ inode->i_op = &sysfs_symlink_inode_operations;
+ return 0;
+}
static int create_dir(struct kobject * k, struct dentry * p,
const char * n, struct dentry ** d)
{
int error;
+ umode_t mode = S_IFDIR| S_IRWXU | S_IRUGO | S_IXUGO;
- down(&p->d_inode->i_sem);
- *d = sysfs_get_dentry(p,n);
+ mutex_lock(&p->d_inode->i_mutex);
+ *d = lookup_one_len(n, p, strlen(n));
if (!IS_ERR(*d)) {
- error = sysfs_create(*d,
- S_IFDIR| S_IRWXU | S_IRUGO | S_IXUGO,
- init_dir);
+ if (sysfs_dirent_exist(p->d_fsdata, n))
+ error = -EEXIST;
+ else
+ error = sysfs_make_dirent(p->d_fsdata, *d, k, mode,
+ SYSFS_DIR);
if (!error) {
- (*d)->d_fsdata = k;
- p->d_inode->i_nlink++;
+ error = sysfs_create(*d, mode, init_dir);
+ if (!error) {
+ inc_nlink(p->d_inode);
+ (*d)->d_op = &sysfs_dentry_ops;
+ d_rehash(*d);
+ }
+ }
+ if (error && (error != -EEXIST)) {
+ struct sysfs_dirent *sd = (*d)->d_fsdata;
+ if (sd) {
+ list_del_init(&sd->s_sibling);
+ sysfs_put(sd);
+ }
+ d_drop(*d);
}
dput(*d);
} else
error = PTR_ERR(*d);
- up(&p->d_inode->i_sem);
+ mutex_unlock(&p->d_inode->i_mutex);
return error;
}
struct dentry * parent;
int error = 0;
- if (!kobj)
- return -EINVAL;
+ BUG_ON(!kobj);
if (kobj->parent)
parent = kobj->parent->dentry;
return error;
}
+/* attaches attribute's sysfs_dirent to the dentry corresponding to the
+ * attribute file
+ */
+static int sysfs_attach_attr(struct sysfs_dirent * sd, struct dentry * dentry)
+{
+ struct attribute * attr = NULL;
+ struct bin_attribute * bin_attr = NULL;
+ int (* init) (struct inode *) = NULL;
+ int error = 0;
+
+ if (sd->s_type & SYSFS_KOBJ_BIN_ATTR) {
+ bin_attr = sd->s_element;
+ attr = &bin_attr->attr;
+ } else {
+ attr = sd->s_element;
+ init = init_file;
+ }
+
+ dentry->d_fsdata = sysfs_get(sd);
+ sd->s_dentry = dentry;
+ error = sysfs_create(dentry, (attr->mode & S_IALLUGO) | S_IFREG, init);
+ if (error) {
+ sysfs_put(sd);
+ return error;
+ }
+
+ if (bin_attr) {
+ dentry->d_inode->i_size = bin_attr->size;
+ dentry->d_inode->i_fop = &bin_fops;
+ }
+ dentry->d_op = &sysfs_dentry_ops;
+ d_rehash(dentry);
+
+ return 0;
+}
+
+static int sysfs_attach_link(struct sysfs_dirent * sd, struct dentry * dentry)
+{
+ int err = 0;
+
+ dentry->d_fsdata = sysfs_get(sd);
+ sd->s_dentry = dentry;
+ err = sysfs_create(dentry, S_IFLNK|S_IRWXUGO, init_symlink);
+ if (!err) {
+ dentry->d_op = &sysfs_dentry_ops;
+ d_rehash(dentry);
+ } else
+ sysfs_put(sd);
+
+ return err;
+}
+
+static struct dentry * sysfs_lookup(struct inode *dir, struct dentry *dentry,
+ struct nameidata *nd)
+{
+ struct sysfs_dirent * parent_sd = dentry->d_parent->d_fsdata;
+ struct sysfs_dirent * sd;
+ int err = 0;
+
+ list_for_each_entry(sd, &parent_sd->s_children, s_sibling) {
+ if (sd->s_type & SYSFS_NOT_PINNED) {
+ const unsigned char * name = sysfs_get_name(sd);
+
+ if (strcmp(name, dentry->d_name.name))
+ continue;
+
+ if (sd->s_type & SYSFS_KOBJ_LINK)
+ err = sysfs_attach_link(sd, dentry);
+ else
+ err = sysfs_attach_attr(sd, dentry);
+ break;
+ }
+ }
+
+ return ERR_PTR(err);
+}
+
+struct inode_operations sysfs_dir_inode_operations = {
+ .lookup = sysfs_lookup,
+ .setattr = sysfs_setattr,
+};
static void remove_dir(struct dentry * d)
{
struct dentry * parent = dget(d->d_parent);
- down(&parent->d_inode->i_sem);
+ struct sysfs_dirent * sd;
+
+ mutex_lock(&parent->d_inode->i_mutex);
d_delete(d);
+ sd = d->d_fsdata;
+ list_del_init(&sd->s_sibling);
+ sysfs_put(sd);
if (d->d_inode)
simple_rmdir(parent->d_inode,d);
pr_debug(" o %s removing done (%d)\n",d->d_name.name,
atomic_read(&d->d_count));
- up(&parent->d_inode->i_sem);
+ mutex_unlock(&parent->d_inode->i_mutex);
dput(parent);
}
void sysfs_remove_dir(struct kobject * kobj)
{
- struct list_head * node;
struct dentry * dentry = dget(kobj->dentry);
+ struct sysfs_dirent * parent_sd;
+ struct sysfs_dirent * sd, * tmp;
if (!dentry)
return;
pr_debug("sysfs %s: removing dir\n",dentry->d_name.name);
- down(&dentry->d_inode->i_sem);
-
- spin_lock(&dcache_lock);
-restart:
- node = dentry->d_subdirs.next;
- while (node != &dentry->d_subdirs) {
- struct dentry * d = list_entry(node,struct dentry,d_child);
-
- node = node->next;
- pr_debug(" o %s (%d): ",d->d_name.name,atomic_read(&d->d_count));
- if (!d_unhashed(d) && (d->d_inode)) {
- d = dget_locked(d);
- pr_debug("removing");
-
- /**
- * Unlink and unhash.
- */
- __d_drop(d);
- spin_unlock(&dcache_lock);
- /* release the target kobject in case of
- * a symlink
- */
- if (S_ISLNK(d->d_inode->i_mode))
- kobject_put(d->d_fsdata);
-
- simple_unlink(dentry->d_inode,d);
- dput(d);
- pr_debug(" done\n");
- spin_lock(&dcache_lock);
- /* re-acquired dcache_lock, need to restart */
- goto restart;
- }
+ mutex_lock(&dentry->d_inode->i_mutex);
+ parent_sd = dentry->d_fsdata;
+ list_for_each_entry_safe(sd, tmp, &parent_sd->s_children, s_sibling) {
+ if (!sd->s_element || !(sd->s_type & SYSFS_NOT_PINNED))
+ continue;
+ list_del_init(&sd->s_sibling);
+ sysfs_drop_dentry(sd, dentry);
+ sysfs_put(sd);
}
- spin_unlock(&dcache_lock);
- up(&dentry->d_inode->i_sem);
+ mutex_unlock(&dentry->d_inode->i_mutex);
remove_dir(dentry);
/**
* Drop reference from dget() on entrance.
*/
dput(dentry);
+ kobj->dentry = NULL;
}
int sysfs_rename_dir(struct kobject * kobj, const char *new_name)
down_write(&sysfs_rename_sem);
parent = kobj->parent->dentry;
- down(&parent->d_inode->i_sem);
+ mutex_lock(&parent->d_inode->i_mutex);
- new_dentry = sysfs_get_dentry(parent, new_name);
+ new_dentry = lookup_one_len(new_name, parent, strlen(new_name));
if (!IS_ERR(new_dentry)) {
if (!new_dentry->d_inode) {
- error = kobject_set_name(kobj,new_name);
- if (!error)
+ error = kobject_set_name(kobj, "%s", new_name);
+ if (!error) {
+ d_add(new_dentry, NULL);
d_move(kobj->dentry, new_dentry);
- }
+ }
+ else
+ d_drop(new_dentry);
+ } else
+ error = -EEXIST;
dput(new_dentry);
}
- up(&parent->d_inode->i_sem);
+ mutex_unlock(&parent->d_inode->i_mutex);
up_write(&sysfs_rename_sem);
return error;
}
-EXPORT_SYMBOL(sysfs_create_dir);
-EXPORT_SYMBOL(sysfs_remove_dir);
-EXPORT_SYMBOL(sysfs_rename_dir);
+int sysfs_move_dir(struct kobject *kobj, struct kobject *new_parent)
+{
+ struct dentry *old_parent_dentry, *new_parent_dentry, *new_dentry;
+ struct sysfs_dirent *new_parent_sd, *sd;
+ int error;
+
+ if (!new_parent)
+ return -EINVAL;
+
+ old_parent_dentry = kobj->parent ?
+ kobj->parent->dentry : sysfs_mount->mnt_sb->s_root;
+ new_parent_dentry = new_parent->dentry;
+
+again:
+ mutex_lock(&old_parent_dentry->d_inode->i_mutex);
+ if (!mutex_trylock(&new_parent_dentry->d_inode->i_mutex)) {
+ mutex_unlock(&old_parent_dentry->d_inode->i_mutex);
+ goto again;
+ }
+
+ new_parent_sd = new_parent_dentry->d_fsdata;
+ sd = kobj->dentry->d_fsdata;
+
+ new_dentry = lookup_one_len(kobj->name, new_parent_dentry,
+ strlen(kobj->name));
+ if (IS_ERR(new_dentry)) {
+ error = PTR_ERR(new_dentry);
+ goto out;
+ } else
+ error = 0;
+ d_add(new_dentry, NULL);
+ d_move(kobj->dentry, new_dentry);
+ dput(new_dentry);
+
+ /* Remove from old parent's list and insert into new parent's list. */
+ list_del_init(&sd->s_sibling);
+ list_add(&sd->s_sibling, &new_parent_sd->s_children);
+
+out:
+ mutex_unlock(&new_parent_dentry->d_inode->i_mutex);
+ mutex_unlock(&old_parent_dentry->d_inode->i_mutex);
+
+ return error;
+}
+
+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;
+
+ mutex_lock(&dentry->d_inode->i_mutex);
+ file->private_data = sysfs_new_dirent(parent_sd, NULL);
+ mutex_unlock(&dentry->d_inode->i_mutex);
+
+ return file->private_data ? 0 : -ENOMEM;
+
+}
+
+static int sysfs_dir_close(struct inode *inode, struct file *file)
+{
+ struct dentry * dentry = file->f_path.dentry;
+ struct sysfs_dirent * cursor = file->private_data;
+
+ mutex_lock(&dentry->d_inode->i_mutex);
+ list_del_init(&cursor->s_sibling);
+ mutex_unlock(&dentry->d_inode->i_mutex);
+
+ release_sysfs_dirent(cursor);
+
+ return 0;
+}
+
+/* Relationship between s_mode and the DT_xxx types */
+static inline unsigned char dt_type(struct sysfs_dirent *sd)
+{
+ return (sd->s_mode >> 12) & 15;
+}
+
+static int sysfs_readdir(struct file * filp, void * dirent, filldir_t filldir)
+{
+ struct dentry *dentry = filp->f_path.dentry;
+ struct sysfs_dirent * parent_sd = dentry->d_fsdata;
+ struct sysfs_dirent *cursor = filp->private_data;
+ struct list_head *p, *q = &cursor->s_sibling;
+ ino_t ino;
+ int i = filp->f_pos;
+
+ switch (i) {
+ case 0:
+ ino = dentry->d_inode->i_ino;
+ if (filldir(dirent, ".", 1, i, ino, DT_DIR) < 0)
+ break;
+ filp->f_pos++;
+ i++;
+ /* fallthrough */
+ case 1:
+ ino = parent_ino(dentry);
+ if (filldir(dirent, "..", 2, i, ino, DT_DIR) < 0)
+ break;
+ filp->f_pos++;
+ i++;
+ /* fallthrough */
+ default:
+ if (filp->f_pos == 2)
+ list_move(q, &parent_sd->s_children);
+
+ for (p=q->next; p!= &parent_sd->s_children; p=p->next) {
+ struct sysfs_dirent *next;
+ const char * name;
+ int len;
+
+ next = list_entry(p, struct sysfs_dirent,
+ s_sibling);
+ if (!next->s_element)
+ continue;
+
+ name = sysfs_get_name(next);
+ len = strlen(name);
+ if (next->s_dentry)
+ ino = next->s_dentry->d_inode->i_ino;
+ else
+ ino = iunique(sysfs_sb, 2);
+
+ if (filldir(dirent, name, len, filp->f_pos, ino,
+ dt_type(next)) < 0)
+ return 0;
+
+ list_move(q, p);
+ p = q;
+ filp->f_pos++;
+ }
+ }
+ return 0;
+}
+
+static loff_t sysfs_dir_lseek(struct file * file, loff_t offset, int origin)
+{
+ struct dentry * dentry = file->f_path.dentry;
+
+ mutex_lock(&dentry->d_inode->i_mutex);
+ switch (origin) {
+ case 1:
+ offset += file->f_pos;
+ case 0:
+ if (offset >= 0)
+ break;
+ default:
+ mutex_unlock(&file->f_path.dentry->d_inode->i_mutex);
+ return -EINVAL;
+ }
+ if (offset != file->f_pos) {
+ file->f_pos = offset;
+ if (file->f_pos >= 2) {
+ struct sysfs_dirent *sd = dentry->d_fsdata;
+ struct sysfs_dirent *cursor = file->private_data;
+ struct list_head *p;
+ loff_t n = file->f_pos - 2;
+
+ list_del(&cursor->s_sibling);
+ p = sd->s_children.next;
+ while (n && p != &sd->s_children) {
+ struct sysfs_dirent *next;
+ next = list_entry(p, struct sysfs_dirent,
+ s_sibling);
+ if (next->s_element)
+ n--;
+ p = p->next;
+ }
+ list_add_tail(&cursor->s_sibling, p);
+ }
+ }
+ mutex_unlock(&dentry->d_inode->i_mutex);
+ return offset;
+}
+const struct file_operations sysfs_dir_operations = {
+ .open = sysfs_dir_open,
+ .release = sysfs_dir_close,
+ .llseek = sysfs_dir_lseek,
+ .read = generic_read_dir,
+ .readdir = sysfs_readdir,
+};