Merge tag 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck...

[linux-drm-fsl-dcu.git] / fs / configfs / dir.c

diff --git a/fs/configfs/dir.c b/fs/configfs/dir.c
index 277bd1be21fd70061fcd8d6694ed65ab4a34abd3..e081acbac2e756372340379fea7a69a84c9c3dd0 100644 (file)
--- a/fs/configfs/dir.c
+++ b/fs/configfs/dir.c
@@ -56,29 +56,28 @@ static void configfs_d_iput(struct dentry * dentry,
        struct configfs_dirent *sd = dentry->d_fsdata;
 
        if (sd) {
-               BUG_ON(sd->s_dentry != dentry);
                /* Coordinate with configfs_readdir */
                spin_lock(&configfs_dirent_lock);
-               sd->s_dentry = NULL;
+               /* Coordinate with configfs_attach_attr where will increase
+                * sd->s_count and update sd->s_dentry to new allocated one.
+                * Only set sd->dentry to null when this dentry is the only
+                * sd owner.
+                * If not do so, configfs_d_iput may run just after
+                * configfs_attach_attr and set sd->s_dentry to null
+                * even it's still in use.
+                */
+               if (atomic_read(&sd->s_count) <= 2)
+                       sd->s_dentry = NULL;
+
                spin_unlock(&configfs_dirent_lock);
                configfs_put(sd);
        }
        iput(inode);
 }
 
-/*
- * We _must_ delete our dentries on last dput, as the chain-to-parent
- * behavior is required to clear the parents of default_groups.
- */
-static int configfs_d_delete(const struct dentry *dentry)
-{
-       return 1;
-}
-
 const struct dentry_operations configfs_dentry_ops = {
        .d_iput         = configfs_d_iput,
-       /* simple_delete_dentry() isn't exported */
-       .d_delete       = configfs_d_delete,
+       .d_delete       = always_delete_dentry,
 };
 
 #ifdef CONFIG_LOCKDEP
@@ -426,8 +425,11 @@ static int configfs_attach_attr(struct configfs_dirent * sd, struct dentry * den
        struct configfs_attribute * attr = sd->s_element;
        int error;
 
+       spin_lock(&configfs_dirent_lock);
        dentry->d_fsdata = configfs_get(sd);
        sd->s_dentry = dentry;
+       spin_unlock(&configfs_dirent_lock);
+
        error = configfs_create(dentry, (attr->ca_mode & S_IALLUGO) | S_IFREG,
                                configfs_init_file);
        if (error) {