/**
* sysfs_name_hash
- * @ns: Namespace tag to hash
* @name: Null terminated string to hash
+ * @ns: Namespace tag to hash
*
* Returns 31 bit hash of ns + name (so it fits in an off_t )
*/
-static unsigned int sysfs_name_hash(const void *ns, const char *name)
+static unsigned int sysfs_name_hash(const char *name, const void *ns)
{
unsigned long hash = init_name_hash();
unsigned int len = strlen(name);
return hash;
}
-static int sysfs_name_compare(unsigned int hash, const void *ns,
- const char *name, const struct sysfs_dirent *sd)
+static int sysfs_name_compare(unsigned int hash, const char *name,
+ const void *ns, const struct sysfs_dirent *sd)
{
if (hash != sd->s_hash)
return hash - sd->s_hash;
static int sysfs_sd_compare(const struct sysfs_dirent *left,
const struct sysfs_dirent *right)
{
- return sysfs_name_compare(left->s_hash, left->s_ns, left->s_name,
+ return sysfs_name_compare(left->s_hash, left->s_name, left->s_ns,
right);
}
/**
* sysfs_addrm_start - prepare for sysfs_dirent add/remove
* @acxt: pointer to sysfs_addrm_cxt to be used
- * @parent_sd: parent sysfs_dirent
*
- * This function is called when the caller is about to add or
- * remove sysfs_dirent under @parent_sd. This function acquires
- * sysfs_mutex. @acxt is used to keep and pass context to
- * other addrm functions.
+ * This function is called when the caller is about to add or remove
+ * sysfs_dirent. This function acquires sysfs_mutex. @acxt is used
+ * to keep and pass context to other addrm functions.
*
* LOCKING:
* Kernel thread context (may sleep). sysfs_mutex is locked on
* return.
*/
-void sysfs_addrm_start(struct sysfs_addrm_cxt *acxt,
- struct sysfs_dirent *parent_sd)
+void sysfs_addrm_start(struct sysfs_addrm_cxt *acxt)
+ __acquires(sysfs_mutex)
{
memset(acxt, 0, sizeof(*acxt));
- acxt->parent_sd = parent_sd;
mutex_lock(&sysfs_mutex);
}
* __sysfs_add_one - add sysfs_dirent to parent without warning
* @acxt: addrm context to use
* @sd: sysfs_dirent to be added
+ * @parent_sd: the parent sysfs_dirent to add @sd to
*
- * 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.
+ * Get @parent_sd and set @sd->s_parent to it and increment nlink of
+ * the 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
* 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)
+int __sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd,
+ struct sysfs_dirent *parent_sd)
{
struct sysfs_inode_attrs *ps_iattr;
int ret;
- sd->s_hash = sysfs_name_hash(sd->s_ns, sd->s_name);
- sd->s_parent = sysfs_get(acxt->parent_sd);
+ sd->s_hash = sysfs_name_hash(sd->s_name, sd->s_ns);
+ sd->s_parent = sysfs_get(parent_sd);
ret = sysfs_link_sibling(sd);
if (ret)
return ret;
/* Update timestamps on the parent */
- ps_iattr = acxt->parent_sd->s_iattr;
+ ps_iattr = 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;
* sysfs_add_one - add sysfs_dirent to parent
* @acxt: addrm context to use
* @sd: sysfs_dirent to be added
+ * @parent_sd: the parent sysfs_dirent to add @sd to
*
- * 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.
+ * Get @parent_sd and set @sd->s_parent to it and increment nlink of
+ * the 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
* 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)
+int sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd,
+ struct sysfs_dirent *parent_sd)
{
int ret;
- ret = __sysfs_add_one(acxt, sd);
+ ret = __sysfs_add_one(acxt, sd, parent_sd);
if (ret == -EEXIST) {
char *path = kzalloc(PATH_MAX, GFP_KERNEL);
WARN(1, KERN_WARNING
"sysfs: cannot create duplicate filename '%s'\n",
(path == NULL) ? sd->s_name
- : (sysfs_pathname(acxt->parent_sd, path),
+ : (sysfs_pathname(parent_sd, path),
strlcat(path, "/", PATH_MAX),
strlcat(path, sd->s_name, PATH_MAX),
path));
{
struct sysfs_inode_attrs *ps_iattr;
- BUG_ON(sd->s_flags & SYSFS_FLAG_REMOVED);
+ /*
+ * 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 = acxt->parent_sd->s_iattr;
+ 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;
* sysfs_mutex is released.
*/
void sysfs_addrm_finish(struct sysfs_addrm_cxt *acxt)
+ __releases(sysfs_mutex)
{
/* release resources acquired by sysfs_addrm_start() */
mutex_unlock(&sysfs_mutex);
* sysfs_find_dirent - find sysfs_dirent with the given name
* @parent_sd: sysfs_dirent to search under
* @name: name to look for
+ * @ns: the namespace tag to use
*
* Look for sysfs_dirent with name @name under @parent_sd.
*
* Pointer to sysfs_dirent if found, NULL if not.
*/
struct sysfs_dirent *sysfs_find_dirent(struct sysfs_dirent *parent_sd,
- const void *ns,
- const unsigned char *name)
+ const unsigned char *name,
+ const void *ns)
{
struct rb_node *node = parent_sd->s_dir.children.rb_node;
unsigned int hash;
- hash = sysfs_name_hash(ns, name);
+ hash = sysfs_name_hash(name, ns);
while (node) {
struct sysfs_dirent *sd;
int result;
sd = to_sysfs_dirent(node);
- result = sysfs_name_compare(hash, ns, name, sd);
+ result = sysfs_name_compare(hash, name, ns, sd);
if (result < 0)
node = node->rb_left;
else if (result > 0)
}
/**
- * sysfs_get_dirent - find and get sysfs_dirent with the given name
+ * sysfs_get_dirent_ns - find and get sysfs_dirent with the given name
* @parent_sd: sysfs_dirent to search under
* @name: name to look for
+ * @ns: the namespace tag to use
*
* Look for sysfs_dirent with name @name under @parent_sd and get
* it if found.
* RETURNS:
* Pointer to sysfs_dirent if found, NULL if not.
*/
-struct sysfs_dirent *sysfs_get_dirent(struct sysfs_dirent *parent_sd,
- const void *ns,
- const unsigned char *name)
+struct sysfs_dirent *sysfs_get_dirent_ns(struct sysfs_dirent *parent_sd,
+ const unsigned char *name,
+ const void *ns)
{
struct sysfs_dirent *sd;
mutex_lock(&sysfs_mutex);
- sd = sysfs_find_dirent(parent_sd, ns, name);
+ sd = sysfs_find_dirent(parent_sd, name, ns);
sysfs_get(sd);
mutex_unlock(&sysfs_mutex);
return sd;
}
-EXPORT_SYMBOL_GPL(sysfs_get_dirent);
+EXPORT_SYMBOL_GPL(sysfs_get_dirent_ns);
static int create_dir(struct kobject *kobj, struct sysfs_dirent *parent_sd,
- const void *ns, const char *name, struct sysfs_dirent **p_sd)
+ const char *name, const void *ns,
+ struct sysfs_dirent **p_sd)
{
umode_t mode = S_IFDIR | S_IRWXU | S_IRUGO | S_IXUGO;
struct sysfs_addrm_cxt acxt;
sd->s_dir.kobj = kobj;
/* link in */
- sysfs_addrm_start(&acxt, parent_sd);
- rc = sysfs_add_one(&acxt, sd);
+ sysfs_addrm_start(&acxt);
+ rc = sysfs_add_one(&acxt, sd, parent_sd);
sysfs_addrm_finish(&acxt);
if (rc == 0)
int sysfs_create_subdir(struct kobject *kobj, const char *name,
struct sysfs_dirent **p_sd)
{
- return create_dir(kobj, kobj->sd, NULL, name, p_sd);
+ return create_dir(kobj, kobj->sd, name, NULL, p_sd);
}
/**
if (!parent_sd)
return -ENOENT;
- error = create_dir(kobj, parent_sd, ns, kobject_name(kobj), &sd);
+ error = create_dir(kobj, parent_sd, kobject_name(kobj), ns, &sd);
if (!error)
kobj->sd = sd;
return error;
if (parent_sd->s_flags & SYSFS_FLAG_HAS_NS)
ns = sysfs_info(dir->i_sb)->ns;
- sd = sysfs_find_dirent(parent_sd, ns, dentry->d_name.name);
+ sd = sysfs_find_dirent(parent_sd, dentry->d_name.name, ns);
/* no such entry */
if (!sd) {
{
struct sysfs_addrm_cxt acxt;
- sysfs_addrm_start(&acxt, sd->s_parent);
+ sysfs_addrm_start(&acxt);
sysfs_remove_one(&acxt, sd);
sysfs_addrm_finish(&acxt);
}
return;
pr_debug("sysfs %s: removing dir\n", dir_sd->s_name);
- sysfs_addrm_start(&acxt, dir_sd);
+ sysfs_addrm_start(&acxt);
pos = rb_first(&dir_sd->s_dir.children);
while (pos) {
struct sysfs_dirent *sd = to_sysfs_dirent(pos);
__sysfs_remove_dir(sd);
}
-int sysfs_rename(struct sysfs_dirent *sd,
- struct sysfs_dirent *new_parent_sd, const void *new_ns,
- const char *new_name)
+int sysfs_rename(struct sysfs_dirent *sd, struct sysfs_dirent *new_parent_sd,
+ const char *new_name, const void *new_ns)
{
int error;
goto out; /* nothing to rename */
error = -EEXIST;
- if (sysfs_find_dirent(new_parent_sd, new_ns, new_name))
+ if (sysfs_find_dirent(new_parent_sd, new_name, new_ns))
goto out;
/* rename sysfs_dirent */
sysfs_get(new_parent_sd);
sysfs_put(sd->s_parent);
sd->s_ns = new_ns;
- sd->s_hash = sysfs_name_hash(sd->s_ns, sd->s_name);
+ sd->s_hash = sysfs_name_hash(sd->s_name, sd->s_ns);
sd->s_parent = new_parent_sd;
sysfs_link_sibling(sd);
{
struct sysfs_dirent *parent_sd = kobj->sd->s_parent;
- return sysfs_rename(kobj->sd, parent_sd, new_ns, new_name);
+ return sysfs_rename(kobj->sd, parent_sd, new_name, new_ns);
}
int sysfs_move_dir_ns(struct kobject *kobj, struct kobject *new_parent_kobj,
new_parent_sd = new_parent_kobj && new_parent_kobj->sd ?
new_parent_kobj->sd : &sysfs_root;
- return sysfs_rename(sd, new_parent_sd, new_ns, sd->s_name);
+ return sysfs_rename(sd, new_parent_sd, sd->s_name, new_ns);
}
/* Relationship between s_mode and the DT_xxx types */