UBUNTU: Start new release

[mirror_ubuntu-bionic-kernel.git] / fs / dcache.c

diff --git a/fs/dcache.c b/fs/dcache.c
index 426bd0a718c061523942bfb616067d9f9075a655..ca3129bfe1089a7d71cded900fc04f6354d2fcaf 100644 (file)
--- a/fs/dcache.c
+++ b/fs/dcache.c
@@ -1868,6 +1868,28 @@ void d_instantiate(struct dentry *entry, struct inode * inode)
 }
 EXPORT_SYMBOL(d_instantiate);
 
+/*
+ * This should be equivalent to d_instantiate() + unlock_new_inode(),
+ * with lockdep-related part of unlock_new_inode() done before
+ * anything else.  Use that instead of open-coding d_instantiate()/
+ * unlock_new_inode() combinations.
+ */
+void d_instantiate_new(struct dentry *entry, struct inode *inode)
+{
+       BUG_ON(!hlist_unhashed(&entry->d_u.d_alias));
+       BUG_ON(!inode);
+       lockdep_annotate_inode_mutex_key(inode);
+       security_d_instantiate(entry, inode);
+       spin_lock(&inode->i_lock);
+       __d_instantiate(entry, inode);
+       WARN_ON(!(inode->i_state & I_NEW));
+       inode->i_state &= ~I_NEW;
+       smp_mb();
+       wake_up_bit(&inode->i_state, __I_NEW);
+       spin_unlock(&inode->i_lock);
+}
+EXPORT_SYMBOL(d_instantiate_new);
+
 /**
  * d_instantiate_no_diralias - instantiate a non-aliased dentry
  * @entry: dentry to complete
@@ -2461,7 +2483,7 @@ struct dentry *d_alloc_parallel(struct dentry *parent,
 
 retry:
        rcu_read_lock();
-       seq = smp_load_acquire(&parent->d_inode->i_dir_seq) & ~1;
+       seq = smp_load_acquire(&parent->d_inode->i_dir_seq);
        r_seq = read_seqbegin(&rename_lock);
        dentry = __d_lookup_rcu(parent, name, &d_seq);
        if (unlikely(dentry)) {
@@ -2482,8 +2504,14 @@ retry:
                rcu_read_unlock();
                goto retry;
        }
+
+       if (unlikely(seq & 1)) {
+               rcu_read_unlock();
+               goto retry;
+       }
+
        hlist_bl_lock(b);
-       if (unlikely(parent->d_inode->i_dir_seq != seq)) {
+       if (unlikely(READ_ONCE(parent->d_inode->i_dir_seq) != seq)) {
                hlist_bl_unlock(b);
                rcu_read_unlock();
                goto retry;