[PATCH net-next 2/6] netlink: add helper for extack attr presence checking
From: Jakub Kicinski <kuba@kernel.org>
Date: 2022-08-24 04:50:44
Subsystem:
networking [general], the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
Being able to check attribute presence and set extack if not on one line is handy, add a helper. Signed-off-by: Jakub Kicinski <kuba@kernel.org> --- include/linux/netlink.h | 11 +++++++++++ 1 file changed, 11 insertions(+)
diff --git a/include/linux/netlink.h b/include/linux/netlink.h
index 24f9fece7599..d20007ad7e26 100644
--- a/include/linux/netlink.h
+++ b/include/linux/netlink.h@@ -139,6 +139,17 @@ struct netlink_ext_ack { } \ } while (0) +#define NL_REQ_ATTR_CHECK(extack, nest, tb, type) ({ \ + struct nlattr **__tb = (tb); \ + u32 __attr = (type); \ + int __retval; \ + \ + __retval = !__tb[__attr]; \ + if (__retval) \ + NL_SET_ERR_ATTR_MISS((extack), (nest), __attr); \ + __retval; \ +}) + static inline void nl_set_extack_cookie_u64(struct netlink_ext_ack *extack, u64 cookie) {
--
2.37.2