On Tue, May 20, 2008 at 12:24:57PM +1000, Barry Naujok wrote:
> +/**
> + * d_drop_neg_children - drop negative child dentries
> + * @parent: parent dentry
> + *
> + * Searches the children of the @parent dentry for negative dentries and
> + * drops them as they are found.
> + *
> + * This is primarily useful for case-insensitive filesystems to drop these
> + * entries when a new entry is created in the parent. The new entry must
> + * be instantiated before calling this function.
> + */
> +
> +void d_drop_neg_children(struct dentry *parent)
please spell out the negative :) also no empty line between the
kerneldoc sand the actual function please.
> +{
> + struct dentry *dentry;
> +
> + spin_lock(&dcache_lock);
> + list_for_each_entry(dentry, &parent->d_subdirs, d_u.d_child) {
> + if (!dentry->d_inode) {
> + spin_lock(&dentry->d_lock);
> + __d_drop(dentry);
> + spin_unlock(&dentry->d_lock);
> + cond_resched_lock(&dcache_lock);
The cond_resched_lock here is not safe here, because the pointer you
are going to dereference in list_for_each_entry might not be valid
anymore. This should look more like:
void d_drop_negative_children(struct dentry *parent)
{
struct dentry *dentry;
again:
spin_lock(&dcache_lock);
list_for_each_entry(dentry, &parent->d_subdirs, d_u.d_child) {
if !dentry->d_inode)
continue;
spin_lock(&dentry->d_lock);
__d_drop(dentry);
spin_unlock(&dentry->d_lock);
if (need_resched()) {
spin_unlock(&dcache_lock);
cond_resched();
goto again;
}
}
spin_unlock(&dcache_lock);
}
Btw, any reason you haven't commited patches 1 and 2 yet? Also maybe
splitting 3 and 4 differently with one patch for the two new functions
in dcache.c and one for the full XFS ascii CI support might be best.
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