[PATCH] configfs: Don't try to d_delete() negative dentries.

From: Joel Becker
Date: Tue Feb 22 2011 - 04:09:49 EST


When configfs is faking mkdir() on its subsystem or default group
objects, it starts by adding a negative dentry. It then tries to
instantiate the group. If that should fail, it must clean up after
itself.

I was using d_delete() here, but configfs_attach_group() promises to
return an empty dentry on error. d_delete() explodes with the entry
dentry. Let's try d_drop() instead. The unhashing is what we want for
our dentry.

Signed-off-by: Joel Becker <jlbec@xxxxxxxxxxxx>
---
fs/configfs/dir.c | 6 ++++--
1 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/fs/configfs/dir.c b/fs/configfs/dir.c
index 90ff3cb..2af26b8 100644
--- a/fs/configfs/dir.c
+++ b/fs/configfs/dir.c
@@ -689,7 +689,8 @@ static int create_default_group(struct config_group *parent_group,
sd = child->d_fsdata;
sd->s_type |= CONFIGFS_USET_DEFAULT;
} else {
- d_delete(child);
+ BUG_ON(child->d_inode);
+ d_drop(child);
dput(child);
}
}
@@ -1683,7 +1684,8 @@ int configfs_register_subsystem(struct configfs_subsystem *subsys)
err = configfs_attach_group(sd->s_element, &group->cg_item,
dentry);
if (err) {
- d_delete(dentry);
+ BUG_ON(dentry->d_inode);
+ d_drop(dentry);
dput(dentry);
} else {
spin_lock(&configfs_dirent_lock);
--
1.7.3.1


--

"But then she looks me in the eye
And says, 'We're going to last forever,'
And man you know I can't begin to doubt it.
Cause it just feels so good and so free and so right,
I know we ain't never going to change our minds about it, Hey!
Here comes my girl."

http://www.jlbec.org/
jlbec@xxxxxxxxxxxx
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