In message <5.1.0.14.2.20030218101309.048d4288@mail1.qualcomm.com> you write:
> At 07:46 PM 2/17/2003, David S. Miller wrote:
>
> >After talking to Alexey, I don't like this patch.
> >
> >The new module subsystem was supposed to deal with things
> >like this cleanly, and this patch is merely a hack to cover
> >up for it's shortcomings.
I don't quite understand.
There are some issue with this patch, however.
Firstly, the owner field should probably be in struct proto_ops not
struct socket, where the function pointers are.
The sk thing looks reasonable at first glance. Getting a reference to
npf->owner, then holding it for the socket is a little confusing, but
an obvious optimization over a naive "get, use, drop, get".
In sys_accept:
> @@ -1196,9 +1198,13 @@
> if (!(newsock = sock_alloc()))
> goto out_put;
>
> - newsock->type = sock->type;
> - newsock->ops = sock->ops;
> + newsock->type = sock->type;
> + newsock->ops = sock->ops;
> + newsock->owner = sock->owner;
>
> + try_module_get(sock->owner);
> + newsock->owner = sock->owner;
> +
> err = sock->ops->accept(sock, newsock, sock->file->f_flags);
> if (err < 0)
> goto out_release;
You still need to check the result of try_module_get, and fail if it
fails. The *only* time this will fail is when someone is doing an
"rmmod --wait" on the module, which presumably means they really do
not want you to increase the reference count furthur.
Hope that helps,
Rusty.
-- Anyone who quotes me in their sig is an idiot. -- Rusty Russell. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
This archive was generated by hypermail 2b29 : Sun Feb 23 2003 - 22:00:24 EST