unsigned add_flags = d_flags_for_inode(inode);
spin_lock(&dentry->d_lock);
- if (inode)
- hlist_add_head(&dentry->d_u.d_alias, &inode->i_dentry);
+ hlist_add_head(&dentry->d_u.d_alias, &inode->i_dentry);
raw_write_seqcount_begin(&dentry->d_seq);
__d_set_inode_and_type(dentry, inode, add_flags);
raw_write_seqcount_end(&dentry->d_seq);
+ __fsnotify_d_instantiate(dentry);
spin_unlock(&dentry->d_lock);
- fsnotify_d_instantiate(dentry, inode);
}
/**
void d_instantiate(struct dentry *entry, struct inode * inode)
{
BUG_ON(!hlist_unhashed(&entry->d_u.d_alias));
- if (inode)
+ if (inode) {
spin_lock(&inode->i_lock);
- __d_instantiate(entry, inode);
- if (inode)
+ __d_instantiate(entry, inode);
spin_unlock(&inode->i_lock);
+ }
security_d_instantiate(entry, inode);
}
EXPORT_SYMBOL(d_instantiate);
-/**
- * d_instantiate_unique - instantiate a non-aliased dentry
- * @entry: dentry to instantiate
- * @inode: inode to attach to this dentry
- *
- * Fill in inode information in the entry. On success, it returns NULL.
- * If an unhashed alias of "entry" already exists, then we return the
- * aliased dentry instead and drop one reference to inode.
- *
- * Note that in order to avoid conflicts with rename() etc, the caller
- * had better be holding the parent directory semaphore.
- *
- * This also assumes that the inode count has been incremented
- * (or otherwise set) by the caller to indicate that it is now
- * in use by the dcache.
- */
-static struct dentry *__d_instantiate_unique(struct dentry *entry,
- struct inode *inode)
-{
- struct dentry *alias;
- int len = entry->d_name.len;
- const char *name = entry->d_name.name;
- unsigned int hash = entry->d_name.hash;
-
- if (!inode) {
- __d_instantiate(entry, NULL);
- return NULL;
- }
-
- hlist_for_each_entry(alias, &inode->i_dentry, d_u.d_alias) {
- /*
- * Don't need alias->d_lock here, because aliases with
- * d_parent == entry->d_parent are not subject to name or
- * parent changes, because the parent inode i_mutex is held.
- */
- if (alias->d_name.hash != hash)
- continue;
- if (alias->d_parent != entry->d_parent)
- continue;
- if (alias->d_name.len != len)
- continue;
- if (dentry_cmp(alias, name, len))
- continue;
- __dget(alias);
- return alias;
- }
-
- __d_instantiate(entry, inode);
- return NULL;
-}
-
-struct dentry *d_instantiate_unique(struct dentry *entry, struct inode *inode)
-{
- struct dentry *result;
-
- BUG_ON(!hlist_unhashed(&entry->d_u.d_alias));
-
- if (inode)
- spin_lock(&inode->i_lock);
- result = __d_instantiate_unique(entry, inode);
- if (inode)
- spin_unlock(&inode->i_lock);
-
- if (!result) {
- security_d_instantiate(entry, inode);
- return NULL;
- }
-
- BUG_ON(!d_unhashed(result));
- iput(inode);
- return result;
-}
-
-EXPORT_SYMBOL(d_instantiate_unique);
-
/**
* d_instantiate_no_diralias - instantiate a non-aliased dentry
* @entry: dentry to complete
}
EXPORT_SYMBOL(d_rehash);
+
+/* inode->i_lock held if inode is non-NULL */
+
+static inline void __d_add(struct dentry *dentry, struct inode *inode)
+{
+ if (inode) {
+ __d_instantiate(dentry, inode);
+ spin_unlock(&inode->i_lock);
+ }
+ security_d_instantiate(dentry, inode);
+ d_rehash(dentry);
+}
+
+/**
+ * d_add - add dentry to hash queues
+ * @entry: dentry to add
+ * @inode: The inode to attach to this dentry
+ *
+ * This adds the entry to the hash queues and initializes @inode.
+ * The entry was actually filled in earlier during d_alloc().
+ */
+
+void d_add(struct dentry *entry, struct inode *inode)
+{
+ if (inode)
+ spin_lock(&inode->i_lock);
+ __d_add(entry, inode);
+}
+EXPORT_SYMBOL(d_add);
+
+/**
+ * d_exact_alias - find and hash an exact unhashed alias
+ * @entry: dentry to add
+ * @inode: The inode to go with this dentry
+ *
+ * If an unhashed dentry with the same name/parent and desired
+ * inode already exists, hash and return it. Otherwise, return
+ * NULL.
+ *
+ * Parent directory should be locked.
+ */
+struct dentry *d_exact_alias(struct dentry *entry, struct inode *inode)
+{
+ struct dentry *alias;
+ int len = entry->d_name.len;
+ const char *name = entry->d_name.name;
+ unsigned int hash = entry->d_name.hash;
+
+ spin_lock(&inode->i_lock);
+ hlist_for_each_entry(alias, &inode->i_dentry, d_u.d_alias) {
+ /*
+ * Don't need alias->d_lock here, because aliases with
+ * d_parent == entry->d_parent are not subject to name or
+ * parent changes, because the parent inode i_mutex is held.
+ */
+ if (alias->d_name.hash != hash)
+ continue;
+ if (alias->d_parent != entry->d_parent)
+ continue;
+ if (alias->d_name.len != len)
+ continue;
+ if (dentry_cmp(alias, name, len))
+ continue;
+ spin_lock(&alias->d_lock);
+ if (!d_unhashed(alias)) {
+ spin_unlock(&alias->d_lock);
+ alias = NULL;
+ } else {
+ __dget_dlock(alias);
+ _d_rehash(alias);
+ spin_unlock(&alias->d_lock);
+ }
+ spin_unlock(&inode->i_lock);
+ return alias;
+ }
+ spin_unlock(&inode->i_lock);
+ return NULL;
+}
+EXPORT_SYMBOL(d_exact_alias);
+
/**
* dentry_update_name_case - update case insensitive dentry with a new name
* @dentry: dentry to be updated
BUG_ON(!d_unhashed(dentry));
- if (!inode) {
- __d_instantiate(dentry, NULL);
+ if (!inode)
goto out;
- }
+
spin_lock(&inode->i_lock);
if (S_ISDIR(inode->i_mode)) {
struct dentry *new = __d_find_any_alias(inode);
return new;
}
}
- /* already taking inode->i_lock, so d_add() by hand */
- __d_instantiate(dentry, inode);
- spin_unlock(&inode->i_lock);
out:
- security_d_instantiate(dentry, inode);
- d_rehash(dentry);
+ __d_add(dentry, inode);
return NULL;
}
EXPORT_SYMBOL(d_splice_alias);
projects / cascardo / linux.git / blobdiff