From 1452b28ca636521b6e16f76787524f83205ec7a3 Mon Sep 17 00:00:00 2001
From: Jesse Gross <jesse@nicira.com>
Date: Fri, 24 Dec 2010 19:53:26 -0800
Subject: [PATCH] datapath: Add get_vport_protected().
In some places we access the array of datapath ports without
RCU protection. This introduces a new function to check that in
these case the dp mutex is held for protection.
Found with sparse.
Signed-off-by: Jesse Gross <jesse@nicira.com>
Acked-by: Ben Pfaff <blp@nicira.com>
---
datapath/datapath.c | 22 +++++++++++++++-------
1 file changed, 15 insertions(+), 7 deletions(-)
diff --git a/datapath/datapath.c b/datapath/datapath.c
index bf9fc820..4df7e9ff 100644
--- a/datapath/datapath.c
+++ b/datapath/datapath.c
@@ -94,9 +94,17 @@ static struct datapath *get_dp_locked(int dp_idx)
return dp;
}
-static struct tbl *get_table_protected(struct datapath *dp)
+static struct tbl *get_table_protected(const struct datapath *dp)
{
- return rcu_dereference_protected(dp->table, lockdep_is_held(&dp->mutex));
+ return rcu_dereference_protected(dp->table,
+ lockdep_is_held(&dp->mutex));
+}
+
+static struct vport *get_vport_protected(const struct datapath *dp,
+ u16 port_no)
+{
+ return rcu_dereference_protected(dp->ports[port_no],
+ lockdep_is_held(&dp->mutex));
}
/* Must be called with rcu_read_lock or RTNL lock. */
@@ -146,7 +154,7 @@ static int dp_fill_ifinfo(struct sk_buff *skb,
NLA_PUT_STRING(skb, IFLA_IFNAME, vport_get_name(port));
NLA_PUT_U32(skb, IFLA_MASTER,
- vport_get_ifindex(rtnl_dereference(dp->ports[ODPP_LOCAL])));
+ vport_get_ifindex(get_vport_protected(dp, ODPP_LOCAL)));
NLA_PUT_U32(skb, IFLA_MTU, vport_get_mtu(port));
#ifdef IFLA_OPERSTATE
NLA_PUT_U8(skb, IFLA_OPERSTATE,
@@ -284,7 +292,7 @@ static int create_dp(int dp_idx, const char __user *devnamep)
return 0;
err_destroy_local_port:
- dp_detach_port(dp->ports[ODPP_LOCAL]);
+ dp_detach_port(get_vport_protected(dp, ODPP_LOCAL));
err_destroy_table:
tbl_destroy(get_table_protected(dp), NULL);
err_free_dp:
@@ -311,7 +319,7 @@ static void do_destroy_dp(struct datapath *dp)
rcu_assign_pointer(dps[dp->dp_idx], NULL);
- dp_detach_port(dp->ports[ODPP_LOCAL]);
+ dp_detach_port(get_vport_protected(dp, ODPP_LOCAL));
tbl_destroy(get_table_protected(dp), flow_free_tbl);
for (i = 0; i < DP_N_QUEUES; i++)
@@ -401,7 +409,7 @@ got_port_no:
goto out_unlock_dp;
set_internal_devs_mtu(dp);
- dp_sysfs_add_if(dp->ports[port_no]);
+ dp_sysfs_add_if(get_vport_protected(dp, port_no));
err = put_user(port_no, &portp->port);
@@ -452,7 +460,7 @@ static int detach_port(int dp_idx, int port_no)
if (!dp)
goto out_unlock_rtnl;
- p = dp->ports[port_no];
+ p = get_vport_protected(dp, port_no);
err = -ENOENT;
if (!p)
goto out_unlock_dp;
--
2.30.2