From fc766e4c4965915ab52a1d1fa3c7a7b3e7bc07f0 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Fri, 29 Oct 2010 03:09:24 +0000 Subject: decnet: RCU conversion and get rid of dev_base_lock While tracking dev_base_lock users, I found decnet used it in dnet_select_source(), but for a wrong purpose: Writers only hold RTNL, not dev_base_lock, so readers must use RCU if they cannot use RTNL. Adds an rcu_head in struct dn_ifaddr and handle proper RCU management. Adds __rcu annotation in dn_route as well. Signed-off-by: Eric Dumazet Acked-by: Steven Whitehouse Signed-off-by: David S. Miller --- include/net/dn_dev.h | 27 ++++++++++++++++++--------- 1 file changed, 18 insertions(+), 9 deletions(-) (limited to 'include/net/dn_dev.h') diff --git a/include/net/dn_dev.h b/include/net/dn_dev.h index 0916bbf3bdff..b9e32db03f20 100644 --- a/include/net/dn_dev.h +++ b/include/net/dn_dev.h @@ -5,13 +5,14 @@ struct dn_dev; struct dn_ifaddr { - struct dn_ifaddr *ifa_next; + struct dn_ifaddr __rcu *ifa_next; struct dn_dev *ifa_dev; __le16 ifa_local; __le16 ifa_address; __u8 ifa_flags; __u8 ifa_scope; char ifa_label[IFNAMSIZ]; + struct rcu_head rcu; }; #define DN_DEV_S_RU 0 /* Run - working normally */ @@ -83,7 +84,7 @@ struct dn_dev_parms { struct dn_dev { - struct dn_ifaddr *ifa_list; + struct dn_ifaddr __rcu *ifa_list; struct net_device *dev; struct dn_dev_parms parms; char use_long; @@ -171,19 +172,27 @@ extern int unregister_dnaddr_notifier(struct notifier_block *nb); static inline int dn_dev_islocal(struct net_device *dev, __le16 addr) { - struct dn_dev *dn_db = dev->dn_ptr; + struct dn_dev *dn_db; struct dn_ifaddr *ifa; + int res = 0; + rcu_read_lock(); + dn_db = rcu_dereference(dev->dn_ptr); if (dn_db == NULL) { printk(KERN_DEBUG "dn_dev_islocal: Called for non DECnet device\n"); - return 0; + goto out; } - for(ifa = dn_db->ifa_list; ifa; ifa = ifa->ifa_next) - if ((addr ^ ifa->ifa_local) == 0) - return 1; - - return 0; + for (ifa = rcu_dereference(dn_db->ifa_list); + ifa != NULL; + ifa = rcu_dereference(ifa->ifa_next)) + if ((addr ^ ifa->ifa_local) == 0) { + res = 1; + break; + } +out: + rcu_read_unlock(); + return res; } #endif /* _NET_DN_DEV_H */ -- cgit v1.2.3-59-g8ed1b