On Thu, Mar 10, 2016 at 02:20:42AM +0000, Al Viro wrote:
> I'll pick it. Mind if I fold it into the one I'd posted (with credits,
> obviously)?
Actually, it's still racy - there's a window between d_obtain_alias() and
ll_d_init() where it can be picked by d_splice_alias().
Sigh... I'm really tempted to just add ->d_init() and let d_alloc() call it
if non-NULL.
The question is what should it get and what should it be the method of...
How about
int (*d_init)(struct dentry *);
in dentry_operations, with __d_alloc() ending with
d_set_d_op(dentry, dentry->d_sb->s_d_op);
if (unlikely(dentry->d_op && dentry->d_op->d_init)) {
int err = dentry->d_op->d_init(dentry);
if (unlikely(err)) {
dentry_free(dentry);
return ERR_PTR(err);
}
}
this_cpu_inc(nr_dentry);
return dentry;
}
Then lustre would simply have
int ll_d_init(struct dentry *de)
{
struct ll_dentry_data *lld = kzalloc(sizeof(*lld), GFP_NOFS);
if (unlikely(!lld))
return -ENOMEM;
lld->lld_invalid = 1;
smp_wmb(); /* read barrier in whatever will find us */
de->d_fsdata = lld;
return 0;
}
as its ->d_init() and forget about all that mess.
Objections, better ideas?
--
To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
