From: Ido Schimmel <idosch@mellanox.com>
Date: Tue, 6 Aug 2019 16:19:56 +0300
Subject: drop_monitor: Use pre_doit / post_doit hooks
Patch-mainline: v5.4-rc1
Git-commit: b19d955055480ac4e03f5afec0ca80f0de7b7013
References: bsc#1154353
Each operation from user space should be protected by the global drop
monitor mutex. Use the pre_doit / post_doit hooks to take / release the
lock instead of doing it explicitly in each function.
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
net/core/drop_monitor.c | 24 +++++++++++++++++-------
1 file changed, 17 insertions(+), 7 deletions(-)
--- a/net/core/drop_monitor.c
+++ b/net/core/drop_monitor.c
@@ -247,12 +247,9 @@ static int set_all_monitor_traces(int st
struct dm_hw_stat_delta *new_stat = NULL;
struct dm_hw_stat_delta *temp;
- mutex_lock(&net_dm_mutex);
-
if (state == trace_state) {
NL_SET_ERR_MSG_MOD(extack, "Trace state already set to requested state");
- rc = -EAGAIN;
- goto out_unlock;
+ return -EAGAIN;
}
switch (state) {
@@ -296,9 +293,6 @@ static int set_all_monitor_traces(int st
else
rc = -EINPROGRESS;
-out_unlock:
- mutex_unlock(&net_dm_mutex);
-
return rc;
}
@@ -380,10 +374,26 @@ static const struct genl_ops dropmon_ops
},
};
+static int net_dm_nl_pre_doit(const struct genl_ops *ops,
+ struct sk_buff *skb, struct genl_info *info)
+{
+ mutex_lock(&net_dm_mutex);
+
+ return 0;
+}
+
+static void net_dm_nl_post_doit(const struct genl_ops *ops,
+ struct sk_buff *skb, struct genl_info *info)
+{
+ mutex_unlock(&net_dm_mutex);
+}
+
static struct genl_family net_drop_monitor_family __ro_after_init = {
.hdrsize = 0,
.name = "NET_DM",
.version = 2,
+ .pre_doit = net_dm_nl_pre_doit,
+ .post_doit = net_dm_nl_post_doit,
.module = THIS_MODULE,
.ops = dropmon_ops,
.n_ops = ARRAY_SIZE(dropmon_ops),