diff options
Diffstat (limited to 'fs/lockd/host.c')
| -rw-r--r-- | fs/lockd/host.c | 49 |
1 files changed, 43 insertions, 6 deletions
diff --git a/fs/lockd/host.c b/fs/lockd/host.c index dbf3fe620a0..1f9d72a7a03 100644 --- a/fs/lockd/host.c +++ b/fs/lockd/host.c @@ -22,7 +22,6 @@ #define NLMDBG_FACILITY NLMDBG_HOSTCACHE #define NLM_HOST_NRHASH 32 -#define NLM_ADDRHASH(addr) (ntohl(addr) & (NLM_HOST_NRHASH-1)) #define NLM_HOST_REBIND (60 * HZ) #define NLM_HOST_EXPIRE (300 * HZ) #define NLM_HOST_COLLECT (120 * HZ) @@ -40,6 +39,48 @@ static struct nsm_handle * nsm_find(const struct sockaddr_in *sin, const char *hostname, unsigned int hostname_len); +/* + * Hash function must work well on big- and little-endian platforms + */ +static unsigned int __nlm_hash32(const __be32 n) +{ + unsigned int hash = (__force u32)n ^ ((__force u32)n >> 16); + return hash ^ (hash >> 8); +} + +static unsigned int __nlm_hash_addr4(const struct sockaddr *sap) +{ + const struct sockaddr_in *sin = (struct sockaddr_in *)sap; + return __nlm_hash32(sin->sin_addr.s_addr); +} + +static unsigned int __nlm_hash_addr6(const struct sockaddr *sap) +{ + const struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap; + const struct in6_addr addr = sin6->sin6_addr; + return __nlm_hash32(addr.s6_addr32[0]) ^ + __nlm_hash32(addr.s6_addr32[1]) ^ + __nlm_hash32(addr.s6_addr32[2]) ^ + __nlm_hash32(addr.s6_addr32[3]); +} + +static unsigned int nlm_hash_address(const struct sockaddr *sap) +{ + unsigned int hash; + + switch (sap->sa_family) { + case AF_INET: + hash = __nlm_hash_addr4(sap); + break; + case AF_INET6: + hash = __nlm_hash_addr6(sap); + break; + default: + hash = 0; + } + return hash & (NLM_HOST_NRHASH - 1); +} + static void nlm_clear_port(struct sockaddr *sap) { switch (sap->sa_family) { @@ -92,16 +133,12 @@ static struct nlm_host *nlm_lookup_host(int server, struct hlist_node *pos; struct nlm_host *host; struct nsm_handle *nsm = NULL; - int hash; dprintk("lockd: nlm_lookup_host(proto=%d, vers=%u," " my role is %s, hostname=%.*s)\n", proto, version, server ? "server" : "client", hostname_len, hostname ? hostname : "<none>"); - hash = NLM_ADDRHASH(sin->sin_addr.s_addr); - - /* Lock hash table */ mutex_lock(&nlm_host_mutex); if (time_after_eq(jiffies, next_gc)) @@ -114,7 +151,7 @@ static struct nlm_host *nlm_lookup_host(int server, * different NLM rpc_clients into one single nlm_host object. * This would allow us to have one nlm_host per address. */ - chain = &nlm_hosts[hash]; + chain = &nlm_hosts[nlm_hash_address((struct sockaddr *)sin)]; hlist_for_each_entry(host, pos, chain, h_hash) { if (!nlm_cmp_addr(nlm_addr(host), (struct sockaddr *)sin)) continue; |