From: Tonghao Zhang xiangxia.m.yue@gmail.com
[ Upstream commit 9cc9a5cb176ccb4f2cda5ac34da5a659926f125f ]
When compiling OvS-master on 4.4.0-81 kernel, there is a warning:
CC [M] /root/ovs/datapath/linux/datapath.o /root/ovs/datapath/linux/datapath.c: In function 'ovs_flow_cmd_set': /root/ovs/datapath/linux/datapath.c:1221:1: warning: the frame size of 1040 bytes is larger than 1024 bytes [-Wframe-larger-than=]
This patch factors out match-init and action-copy to avoid "Wframe-larger-than=1024" warning. Because mask is only used to get actions, we new a function to save some stack space.
Signed-off-by: Tonghao Zhang xiangxia.m.yue@gmail.com Acked-by: Pravin B Shelar pshelar@ovn.org Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin alexander.levin@microsoft.com --- net/openvswitch/datapath.c | 81 +++++++++++++++++++++++++++++++++------------- 1 file changed, 58 insertions(+), 23 deletions(-)
diff --git a/net/openvswitch/datapath.c b/net/openvswitch/datapath.c index 453f806afe6e..0f594140c5ff 100644 --- a/net/openvswitch/datapath.c +++ b/net/openvswitch/datapath.c @@ -1105,6 +1105,58 @@ static struct sw_flow_actions *get_flow_actions(struct net *net, return acts; }
+/* Factor out match-init and action-copy to avoid + * "Wframe-larger-than=1024" warning. Because mask is only + * used to get actions, we new a function to save some + * stack space. + * + * If there are not key and action attrs, we return 0 + * directly. In the case, the caller will also not use the + * match as before. If there is action attr, we try to get + * actions and save them to *acts. Before returning from + * the function, we reset the match->mask pointer. Because + * we should not to return match object with dangling reference + * to mask. + * */ +static int ovs_nla_init_match_and_action(struct net *net, + struct sw_flow_match *match, + struct sw_flow_key *key, + struct nlattr **a, + struct sw_flow_actions **acts, + bool log) +{ + struct sw_flow_mask mask; + int error = 0; + + if (a[OVS_FLOW_ATTR_KEY]) { + ovs_match_init(match, key, true, &mask); + error = ovs_nla_get_match(net, match, a[OVS_FLOW_ATTR_KEY], + a[OVS_FLOW_ATTR_MASK], log); + if (error) + goto error; + } + + if (a[OVS_FLOW_ATTR_ACTIONS]) { + if (!a[OVS_FLOW_ATTR_KEY]) { + OVS_NLERR(log, + "Flow key attribute not present in set flow."); + return -EINVAL; + } + + *acts = get_flow_actions(net, a[OVS_FLOW_ATTR_ACTIONS], key, + &mask, log); + if (IS_ERR(*acts)) { + error = PTR_ERR(*acts); + goto error; + } + } + + /* On success, error is 0. */ +error: + match->mask = NULL; + return error; +} + static int ovs_flow_cmd_set(struct sk_buff *skb, struct genl_info *info) { struct net *net = sock_net(skb->sk); @@ -1112,7 +1164,6 @@ static int ovs_flow_cmd_set(struct sk_buff *skb, struct genl_info *info) struct ovs_header *ovs_header = info->userhdr; struct sw_flow_key key; struct sw_flow *flow; - struct sw_flow_mask mask; struct sk_buff *reply = NULL; struct datapath *dp; struct sw_flow_actions *old_acts = NULL, *acts = NULL; @@ -1124,34 +1175,18 @@ static int ovs_flow_cmd_set(struct sk_buff *skb, struct genl_info *info) bool ufid_present;
ufid_present = ovs_nla_get_ufid(&sfid, a[OVS_FLOW_ATTR_UFID], log); - if (a[OVS_FLOW_ATTR_KEY]) { - ovs_match_init(&match, &key, true, &mask); - error = ovs_nla_get_match(net, &match, a[OVS_FLOW_ATTR_KEY], - a[OVS_FLOW_ATTR_MASK], log); - } else if (!ufid_present) { + if (!a[OVS_FLOW_ATTR_KEY] && !ufid_present) { OVS_NLERR(log, "Flow set message rejected, Key attribute missing."); - error = -EINVAL; + return -EINVAL; } + + error = ovs_nla_init_match_and_action(net, &match, &key, a, + &acts, log); if (error) goto error;
- /* Validate actions. */ - if (a[OVS_FLOW_ATTR_ACTIONS]) { - if (!a[OVS_FLOW_ATTR_KEY]) { - OVS_NLERR(log, - "Flow key attribute not present in set flow."); - error = -EINVAL; - goto error; - } - - acts = get_flow_actions(net, a[OVS_FLOW_ATTR_ACTIONS], &key, - &mask, log); - if (IS_ERR(acts)) { - error = PTR_ERR(acts); - goto error; - } - + if (acts) { /* Can allocate before locking if have acts. */ reply = ovs_flow_cmd_alloc_info(acts, &sfid, info, false, ufid_flags);