diff options
Diffstat (limited to 'net/ipv4/devinet.c')
| -rw-r--r-- | net/ipv4/devinet.c | 78 |
1 files changed, 78 insertions, 0 deletions
diff --git a/net/ipv4/devinet.c b/net/ipv4/devinet.c index 036652c..6d85800d 100644 --- a/net/ipv4/devinet.c +++ b/net/ipv4/devinet.c @@ -51,6 +51,7 @@ #include <linux/inetdevice.h> #include <linux/igmp.h> #include <linux/slab.h> +#include <linux/hash.h> #ifdef CONFIG_SYSCTL #include <linux/sysctl.h> #endif @@ -92,6 +93,71 @@ static const struct nla_policy ifa_ipv4_policy[IFA_MAX+1] = { [IFA_LABEL] = { .type = NLA_STRING, .len = IFNAMSIZ - 1 }, }; +/* inet_addr_hash's shifting is dependent upon this IN4_ADDR_HSIZE + * value. So if you change this define, make appropriate changes to + * inet_addr_hash as well. + */ +#define IN4_ADDR_HSIZE 256 +static struct hlist_head inet_addr_lst[IN4_ADDR_HSIZE]; +static DEFINE_SPINLOCK(inet_addr_hash_lock); + +static inline unsigned int inet_addr_hash(struct net *net, __be32 addr) +{ + u32 val = (__force u32) addr ^ hash_ptr(net, 8); + + return ((val ^ (val >> 8) ^ (val >> 16) ^ (val >> 24)) & + (IN4_ADDR_HSIZE - 1)); +} + +static void inet_hash_insert(struct net *net, struct in_ifaddr *ifa) +{ + unsigned int hash = inet_addr_hash(net, ifa->ifa_local); + + spin_lock(&inet_addr_hash_lock); + hlist_add_head_rcu(&ifa->hash, &inet_addr_lst[hash]); + spin_unlock(&inet_addr_hash_lock); +} + +static void inet_hash_remove(struct in_ifaddr *ifa) +{ + spin_lock(&inet_addr_hash_lock); + hlist_del_init_rcu(&ifa->hash); + spin_unlock(&inet_addr_hash_lock); +} + +/** + * __ip_dev_find - find the first device with a given source address. + * @net: the net namespace + * @addr: the source address + * @devref: if true, take a reference on the found device + * + * If a caller uses devref=false, it should be protected by RCU, or RTNL + */ +struct net_device *__ip_dev_find(struct net *net, __be32 addr, bool devref) +{ + unsigned int hash = inet_addr_hash(net, addr); + struct net_device *result = NULL; + struct in_ifaddr *ifa; + struct hlist_node *node; + + rcu_read_lock(); + hlist_for_each_entry_rcu(ifa, node, &inet_addr_lst[hash], hash) { + struct net_device *dev = ifa->ifa_dev->dev; + + if (!net_eq(dev_net(dev), net)) + continue; + if (ifa->ifa_local == addr) { + result = dev; + break; + } + } + if (result && devref) + dev_hold(result); + rcu_read_unlock(); + return result; +} +EXPORT_SYMBOL(__ip_dev_find); + static void rtmsg_ifa(int event, struct in_ifaddr *, struct nlmsghdr *, u32); static BLOCKING_NOTIFIER_HEAD(inetaddr_chain); @@ -265,6 +331,7 @@ static void __inet_del_ifa(struct in_device *in_dev, struct in_ifaddr **ifap, } if (!do_promote) { + inet_hash_remove(ifa); *ifap1 = ifa->ifa_next; rtmsg_ifa(RTM_DELADDR, ifa, nlh, pid); @@ -281,6 +348,7 @@ static void __inet_del_ifa(struct in_device *in_dev, struct in_ifaddr **ifap, /* 2. Unlink it */ *ifap = ifa1->ifa_next; + inet_hash_remove(ifa1); /* 3. Announce address deletion */ @@ -368,6 +436,8 @@ static int __inet_insert_ifa(struct in_ifaddr *ifa, struct nlmsghdr *nlh, ifa->ifa_next = *ifap; *ifap = ifa; + inet_hash_insert(dev_net(in_dev->dev), ifa); + /* Send message first, then call notifier. Notifier will trigger FIB update, so that listeners of netlink will know about new ifaddr */ @@ -521,6 +591,7 @@ static struct in_ifaddr *rtm_to_ifaddr(struct net *net, struct nlmsghdr *nlh) if (tb[IFA_ADDRESS] == NULL) tb[IFA_ADDRESS] = tb[IFA_LOCAL]; + INIT_HLIST_NODE(&ifa->hash); ifa->ifa_prefixlen = ifm->ifa_prefixlen; ifa->ifa_mask = inet_make_mask(ifm->ifa_prefixlen); ifa->ifa_flags = ifm->ifa_flags; @@ -728,6 +799,7 @@ int devinet_ioctl(struct net *net, unsigned int cmd, void __user *arg) if (!ifa) { ret = -ENOBUFS; ifa = inet_alloc_ifa(); + INIT_HLIST_NODE(&ifa->hash); if (!ifa) break; if (colon) @@ -1084,6 +1156,7 @@ static int inetdev_event(struct notifier_block *this, unsigned long event, struct in_ifaddr *ifa = inet_alloc_ifa(); if (ifa) { + INIT_HLIST_NODE(&ifa->hash); ifa->ifa_local = ifa->ifa_address = htonl(INADDR_LOOPBACK); ifa->ifa_prefixlen = 8; @@ -1720,6 +1793,11 @@ static struct rtnl_af_ops inet_af_ops = { void __init devinet_init(void) { + int i; + + for (i = 0; i < IN4_ADDR_HSIZE; i++) + INIT_HLIST_HEAD(&inet_addr_lst[i]); + register_pernet_subsys(&devinet_ops); register_gifconf(PF_INET, inet_gifconf); |
