diff options
| author | Joe Damato <jdamato@fastly.com> | 2025-02-14 21:12:29 +0000 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2025-02-17 16:46:03 -0800 |
| commit | a127c18462ea619a1ace1f00540807e009dbf225 (patch) | |
| tree | 9b7bd2e9a8b7948ba7fe95ec172e111540a9bfdb | |
| parent | c935af429ec2344ffe716f869ddde43f5f1b20dc (diff) | |
netlink: Add nla_put_empty_nest helper
Creating empty nests is helpful when the exact attributes to be exposed
in the future are not known. Encapsulate the logic in a helper.
Signed-off-by: Joe Damato <jdamato@fastly.com>
Suggested-by: Jakub Kicinski <kuba@kernel.org>
Link: https://patch.msgid.link/20250214211255.14194-2-jdamato@fastly.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
| -rw-r--r-- | include/net/netlink.h | 15 |
1 files changed, 15 insertions, 0 deletions
diff --git a/include/net/netlink.h b/include/net/netlink.h index e015ffbed819..29e0db940382 100644 --- a/include/net/netlink.h +++ b/include/net/netlink.h @@ -118,6 +118,7 @@ * nla_nest_start(skb, type) start a nested attribute * nla_nest_end(skb, nla) finalize a nested attribute * nla_nest_cancel(skb, nla) cancel nested attribute construction + * nla_put_empty_nest(skb, type) create an empty nest * * Attribute Length Calculations: * nla_attr_size(payload) length of attribute w/o padding @@ -2241,6 +2242,20 @@ static inline void nla_nest_cancel(struct sk_buff *skb, struct nlattr *start) } /** + * nla_put_empty_nest - Create an empty nest + * @skb: socket buffer the message is stored in + * @attrtype: attribute type of the container + * + * This function is a helper for creating empty nests. + * + * Returns: 0 when successful or -EMSGSIZE on failure. + */ +static inline int nla_put_empty_nest(struct sk_buff *skb, int attrtype) +{ + return nla_nest_start(skb, attrtype) ? 0 : -EMSGSIZE; +} + +/** * __nla_validate_nested - Validate a stream of nested attributes * @start: container attribute * @maxtype: maximum attribute type to be expected |