diff options
Diffstat (limited to 'fs/kernfs/dir.c')
| -rw-r--r-- | fs/kernfs/dir.c | 24 |
1 files changed, 17 insertions, 7 deletions
diff --git a/fs/kernfs/dir.c b/fs/kernfs/dir.c index 3990f3e270cb..6acd9c3d4cff 100644 --- a/fs/kernfs/dir.c +++ b/fs/kernfs/dir.c @@ -1073,20 +1073,30 @@ static int kernfs_dop_revalidate(struct dentry *dentry, unsigned int flags) /* If the kernfs parent node has changed discard and * proceed to ->lookup. + * + * There's nothing special needed here when getting the + * dentry parent, even if a concurrent rename is in + * progress. That's because the dentry is negative so + * it can only be the target of the rename and it will + * be doing a d_move() not a replace. Consequently the + * dentry d_parent won't change over the d_move(). + * + * Also kernfs negative dentries transitioning from + * negative to positive during revalidate won't happen + * because they are invalidated on containing directory + * changes and the lookup re-done so that a new positive + * dentry can be properly created. */ - spin_lock(&dentry->d_lock); + root = kernfs_root_from_sb(dentry->d_sb); + down_read(&root->kernfs_rwsem); parent = kernfs_dentry_node(dentry->d_parent); if (parent) { - spin_unlock(&dentry->d_lock); - root = kernfs_root(parent); - down_read(&root->kernfs_rwsem); if (kernfs_dir_changed(parent, dentry)) { up_read(&root->kernfs_rwsem); return 0; } - up_read(&root->kernfs_rwsem); - } else - spin_unlock(&dentry->d_lock); + } + up_read(&root->kernfs_rwsem); /* The kernfs parent node hasn't changed, leave the * dentry negative and return success. |