- struct dentry * result;
- struct inode *dir = parent->d_inode;
-
- mutex_lock(&dir->i_mutex);
- /*
- * First re-do the cached lookup just in case it was created
- * while we waited for the directory semaphore..
- *
- * FIXME! This could use version numbering or similar to
- * avoid unnecessary cache lookups.
- *
- * The "dcache_lock" is purely to protect the RCU list walker
- * from concurrent renames at this point (we mustn't get false
- * negatives from the RCU list walk here, unlike the optimistic
- * fast walk).
- *
- * so doing d_lookup() (with seqlock), instead of lockfree __d_lookup
- */
- result = d_lookup(parent, name);
- if (!result) {
- struct dentry *dentry;
-
- /* Don't create child dentry for a dead directory. */
- result = ERR_PTR(-ENOENT);
- if (IS_DEADDIR(dir))
- goto out_unlock;
-
- dentry = d_alloc(parent, name);
- result = ERR_PTR(-ENOMEM);
- if (dentry) {
- result = dir->i_op->lookup(dir, dentry, nd);
- if (result)
- dput(dentry);
- else
- result = dentry;
- }
-out_unlock:
- mutex_unlock(&dir->i_mutex);
- return result;
- }
-
- /*
- * Uhhuh! Nasty case: the cache was re-populated while
- * we waited on the semaphore. Need to revalidate.
- */
- mutex_unlock(&dir->i_mutex);
- if (result->d_op && result->d_op->d_revalidate) {
- result = do_revalidate(result, nd);
- if (!result)
- result = ERR_PTR(-ENOENT);