static void __d_free(struct dentry *dentry)
{
+ WARN_ON(!list_empty(&dentry->d_alias));
if (dname_external(dentry))
kfree(dentry->d_name.name);
kmem_cache_free(dentry_cache, dentry);
return d_alloc(parent, &q);
}
+/* the caller must hold dcache_lock */
+static void __d_instantiate(struct dentry *dentry, struct inode *inode)
+{
+ if (inode)
+ list_add(&dentry->d_alias, &inode->i_dentry);
+ dentry->d_inode = inode;
+ fsnotify_d_instantiate(dentry, inode);
+}
+
/**
* d_instantiate - fill in inode information for a dentry
* @entry: dentry to complete
{
BUG_ON(!list_empty(&entry->d_alias));
spin_lock(&dcache_lock);
- if (inode)
- list_add(&entry->d_alias, &inode->i_dentry);
- entry->d_inode = inode;
- fsnotify_d_instantiate(entry, inode);
+ __d_instantiate(entry, inode);
spin_unlock(&dcache_lock);
security_d_instantiate(entry, inode);
}
unsigned int hash = entry->d_name.hash;
if (!inode) {
- entry->d_inode = NULL;
+ __d_instantiate(entry, NULL);
return NULL;
}
return alias;
}
- list_add(&entry->d_alias, &inode->i_dentry);
- entry->d_inode = inode;
- fsnotify_d_instantiate(entry, inode);
+ __d_instantiate(entry, inode);
return NULL;
}
new = __d_find_alias(inode, 1);
if (new) {
BUG_ON(!(new->d_flags & DCACHE_DISCONNECTED));
- fsnotify_d_instantiate(new, inode);
spin_unlock(&dcache_lock);
security_d_instantiate(new, inode);
d_rehash(dentry);
d_move(new, dentry);
iput(inode);
} else {
- /* d_instantiate takes dcache_lock, so we do it by hand */
- list_add(&dentry->d_alias, &inode->i_dentry);
- dentry->d_inode = inode;
- fsnotify_d_instantiate(dentry, inode);
+ /* already taking dcache_lock, so d_add() by hand */
+ __d_instantiate(dentry, inode);
spin_unlock(&dcache_lock);
security_d_instantiate(dentry, inode);
d_rehash(dentry);
* d_instantiate() by hand because it takes dcache_lock which
* we already hold.
*/
- list_add(&found->d_alias, &inode->i_dentry);
- found->d_inode = inode;
+ __d_instantiate(found, inode);
spin_unlock(&dcache_lock);
security_d_instantiate(found, inode);
return found;
* d_validate - verify dentry provided from insecure source
* @dentry: The dentry alleged to be valid child of @dparent
* @dparent: The parent dentry (known to be valid)
- * @hash: Hash of the dentry
- * @len: Length of the name
*
* An insecure source has sent us a dentry, here we verify it and dget() it.
* This is used by ncpfs in its readdir implementation.
spin_unlock(&dcache_lock);
}
-/*
- * Helper that returns 1 if p1 is a parent of p2, else 0
+/**
+ * d_ancestor - search for an ancestor
+ * @p1: ancestor dentry
+ * @p2: child dentry
+ *
+ * Returns the ancestor dentry of p2 which is a child of p1, if p1 is
+ * an ancestor of p2, else NULL.
*/
-static int d_isparent(struct dentry *p1, struct dentry *p2)
+struct dentry *d_ancestor(struct dentry *p1, struct dentry *p2)
{
struct dentry *p;
for (p = p2; !IS_ROOT(p); p = p->d_parent) {
if (p->d_parent == p1)
- return 1;
+ return p;
}
- return 0;
+ return NULL;
}
/*
/* Check for loops */
ret = ERR_PTR(-ELOOP);
- if (d_isparent(alias, dentry))
+ if (d_ancestor(alias, dentry))
goto out_err;
/* See lock_rename() */
if (!inode) {
actual = dentry;
- dentry->d_inode = NULL;
+ __d_instantiate(dentry, NULL);
goto found_lock;
}
* Caller must ensure that "new_dentry" is pinned before calling is_subdir()
*/
-int is_subdir(struct dentry * new_dentry, struct dentry * old_dentry)
+int is_subdir(struct dentry *new_dentry, struct dentry *old_dentry)
{
int result;
- struct dentry * saved = new_dentry;
unsigned long seq;
- /* need rcu_readlock to protect against the d_parent trashing due to
- * d_move
+ /* FIXME: This is old behavior, needed? Please check callers. */
+ if (new_dentry == old_dentry)
+ return 1;
+
+ /*
+ * Need rcu_readlock to protect against the d_parent trashing
+ * due to d_move
*/
rcu_read_lock();
- do {
+ do {
/* for restarting inner loop in case of seq retry */
- new_dentry = saved;
- result = 0;
seq = read_seqbegin(&rename_lock);
- for (;;) {
- if (new_dentry != old_dentry) {
- if (IS_ROOT(new_dentry))
- break;
- new_dentry = new_dentry->d_parent;
- continue;
- }
+ if (d_ancestor(old_dentry, new_dentry))
result = 1;
- break;
- }
+ else
+ result = 0;
} while (read_seqretry(&rename_lock, seq));
rcu_read_unlock();