ovl: rearrange ovl_follow_link to it doesn't need to call ->put_link

ovl_follow_link current calls ->put_link on an error path.
However ->put_link is about to change in a way that it will be
impossible to call it from ovl_follow_link.

So rearrange the code to avoid the need for that error path.
Specifically: move the kmalloc() call before the ->follow_link()
call to the subordinate filesystem.

Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
NeilBrown 2015-03-23 13:37:39 +11:00 committed by Al Viro
parent 90e4fc8890
commit 3188b2955d
1 changed files with 12 additions and 13 deletions

View File

@ -145,6 +145,7 @@ static void *ovl_follow_link(struct dentry *dentry, struct nameidata *nd)
void *ret;
struct dentry *realdentry;
struct inode *realinode;
struct ovl_link_data *data = NULL;
realdentry = ovl_dentry_real(dentry);
realinode = realdentry->d_inode;
@ -152,25 +153,23 @@ static void *ovl_follow_link(struct dentry *dentry, struct nameidata *nd)
if (WARN_ON(!realinode->i_op->follow_link))
return ERR_PTR(-EPERM);
ret = realinode->i_op->follow_link(realdentry, nd);
if (IS_ERR(ret))
return ret;
if (realinode->i_op->put_link) {
struct ovl_link_data *data;
data = kmalloc(sizeof(struct ovl_link_data), GFP_KERNEL);
if (!data) {
realinode->i_op->put_link(realdentry, nd, ret);
if (!data)
return ERR_PTR(-ENOMEM);
}
data->realdentry = realdentry;
}
ret = realinode->i_op->follow_link(realdentry, nd);
if (IS_ERR(ret)) {
kfree(data);
return ret;
}
if (data)
data->cookie = ret;
return data;
} else {
return NULL;
}
return data;
}
static void ovl_put_link(struct dentry *dentry, struct nameidata *nd, void *c)