1 files changed, 246 insertions, 164 deletions

diff --git a/fs/lockd/host.c b/fs/lockd/host.c
index ed0c59fe23ce..b7c99bfb3da6 100644
--- a/fs/lockd/host.c
+++ b/fs/lockd/host.c
@@ -25,9 +25,22 @@
 #define NLM_HOST_EXPIRE         (300 * HZ)
 #define NLM_HOST_COLLECT        (120 * HZ)
 
-static struct hlist_head        nlm_hosts[NLM_HOST_NRHASH];
+static struct hlist_head        nlm_server_hosts[NLM_HOST_NRHASH];
+static struct hlist_head        nlm_client_hosts[NLM_HOST_NRHASH];
+
+#define for_each_host(host, pos, chain, table) \
+        for ((chain) = (table); \
+             (chain) < (table) + NLM_HOST_NRHASH; ++(chain)) \
+                hlist_for_each_entry((host), (pos), (chain), h_hash)
+
+#define for_each_host_safe(host, pos, next, chain, table) \
+        for ((chain) = (table); \
+             (chain) < (table) + NLM_HOST_NRHASH; ++(chain)) \
+                hlist_for_each_entry_safe((host), (pos), (next), \
+                                                (chain), h_hash)
+
 static unsigned long            next_gc;
-static int                      nrhosts;
+static unsigned long            nrhosts;
 static DEFINE_MUTEX(nlm_host_mutex);
 
 static void                     nlm_gc_hosts(void);
@@ -40,8 +53,6 @@ struct nlm_lookup_host_info {
         const u32               version;        /* NLM version to search for */
         const char              *hostname;      /* remote's hostname */
         const size_t            hostname_len;   /* it's length */
-        const struct sockaddr   *src_sap;       /* our address (optional) */
-        const size_t            src_len;        /* it's length */
         const int               noresvport;     /* use non-priv port */
 };
 
@@ -88,127 +99,83 @@ static unsigned int nlm_hash_address(const struct sockaddr *sap)
 }
 
 /*
- * Common host lookup routine for server & client
+ * Allocate and initialize an nlm_host.  Common to both client and server.
  */
-static struct nlm_host *nlm_lookup_host(struct nlm_lookup_host_info *ni)
+static struct nlm_host *nlm_alloc_host(struct nlm_lookup_host_info *ni,
+                                       struct nsm_handle *nsm)
 {
-        struct hlist_head *chain;
-        struct hlist_node *pos;
-        struct nlm_host *host;
-        struct nsm_handle *nsm = NULL;
-
-        mutex_lock(&nlm_host_mutex);
-
-        if (time_after_eq(jiffies, next_gc))
-                nlm_gc_hosts();
-
-        /* We may keep several nlm_host objects for a peer, because each
-         * nlm_host is identified by
-         * (address, protocol, version, server/client)
-         * We could probably simplify this a little by putting all those
-         * different NLM rpc_clients into one single nlm_host object.
-         * This would allow us to have one nlm_host per address.
-         */
-        chain = &nlm_hosts[nlm_hash_address(ni->sap)];
-        hlist_for_each_entry(host, pos, chain, h_hash) {
-                if (!rpc_cmp_addr(nlm_addr(host), ni->sap))
-                        continue;
-
-                /* See if we have an NSM handle for this client */
-                if (!nsm)
-                        nsm = host->h_nsmhandle;
-
-                if (host->h_proto != ni->protocol)
-                        continue;
-                if (host->h_version != ni->version)
-                        continue;
-                if (host->h_server != ni->server)
-                        continue;
-                if (ni->server && ni->src_len != 0 &&
-                    !rpc_cmp_addr(nlm_srcaddr(host), ni->src_sap))
-                        continue;
-
-                /* Move to head of hash chain. */
-                hlist_del(&host->h_hash);
-                hlist_add_head(&host->h_hash, chain);
-
-                nlm_get_host(host);
-                dprintk("lockd: nlm_lookup_host found host %s (%s)\n",
-                                host->h_name, host->h_addrbuf);
-                goto out;
-        }
+        struct nlm_host *host = NULL;
+        unsigned long now = jiffies;
 
-        /*
-         * The host wasn't in our hash table.  If we don't
-         * have an NSM handle for it yet, create one.
-         */
-        if (nsm)
+        if (nsm != NULL)
                 atomic_inc(&nsm->sm_count);
         else {
                 host = NULL;
                 nsm = nsm_get_handle(ni->sap, ni->salen,
                                         ni->hostname, ni->hostname_len);
-                if (!nsm) {
-                        dprintk("lockd: nlm_lookup_host failed; "
-                                "no nsm handle\n");
+                if (unlikely(nsm == NULL)) {
+                        dprintk("lockd: %s failed; no nsm handle\n",
+                                __func__);
                         goto out;
                 }
         }
 
-        host = kzalloc(sizeof(*host), GFP_KERNEL);
-        if (!host) {
+        host = kmalloc(sizeof(*host), GFP_KERNEL);
+        if (unlikely(host == NULL)) {
+                dprintk("lockd: %s failed; no memory\n", __func__);
                 nsm_release(nsm);
-                dprintk("lockd: nlm_lookup_host failed; no memory\n");
                 goto out;
         }
-        host->h_name       = nsm->sm_name;
-        host->h_addrbuf    = nsm->sm_addrbuf;
+
         memcpy(nlm_addr(host), ni->sap, ni->salen);
-        host->h_addrlen = ni->salen;
+        host->h_addrlen    = ni->salen;
         rpc_set_port(nlm_addr(host), 0);
-        memcpy(nlm_srcaddr(host), ni->src_sap, ni->src_len);
-        host->h_srcaddrlen = ni->src_len;
+        host->h_srcaddrlen = 0;
+
+        host->h_rpcclnt    = NULL;
+        host->h_name       = nsm->sm_name;
         host->h_version    = ni->version;
         host->h_proto      = ni->protocol;
-        host->h_rpcclnt    = NULL;
-        mutex_init(&host->h_mutex);
-        host->h_nextrebind = jiffies + NLM_HOST_REBIND;
-        host->h_expires    = jiffies + NLM_HOST_EXPIRE;
-        atomic_set(&host->h_count, 1);
+        host->h_reclaiming = 0;
+        host->h_server     = ni->server;
+        host->h_noresvport = ni->noresvport;
+        host->h_inuse      = 0;
         init_waitqueue_head(&host->h_gracewait);
         init_rwsem(&host->h_rwsem);
-        host->h_state      = 0;                 /* pseudo NSM state */
-        host->h_nsmstate   = 0;                 /* real NSM state */
-        host->h_nsmhandle  = nsm;
-        host->h_server     = ni->server;
-        host->h_noresvport = ni->noresvport;
-        hlist_add_head(&host->h_hash, chain);
+        host->h_state      = 0;
+        host->h_nsmstate   = 0;
+        host->h_pidcount   = 0;
+        atomic_set(&host->h_count, 1);
+        mutex_init(&host->h_mutex);
+        host->h_nextrebind = now + NLM_HOST_REBIND;
+        host->h_expires    = now + NLM_HOST_EXPIRE;
         INIT_LIST_HEAD(&host->h_lockowners);
         spin_lock_init(&host->h_lock);
         INIT_LIST_HEAD(&host->h_granted);
         INIT_LIST_HEAD(&host->h_reclaim);
-
-        nrhosts++;
-
-        dprintk("lockd: nlm_lookup_host created host %s\n",
-                        host->h_name);
+        host->h_nsmhandle  = nsm;
+        host->h_addrbuf    = nsm->sm_addrbuf;
 
 out:
-        mutex_unlock(&nlm_host_mutex);
         return host;
 }
 
 /*
- * Destroy a host
+ * Destroy an nlm_host and free associated resources
+ *
+ * Caller must hold nlm_host_mutex.
  */
-static void
-nlm_destroy_host(struct nlm_host *host)
+static void nlm_destroy_host_locked(struct nlm_host *host)
 {
         struct rpc_clnt *clnt;
 
+        dprintk("lockd: destroy host %s\n", host->h_name);
+
         BUG_ON(!list_empty(&host->h_lockowners));
         BUG_ON(atomic_read(&host->h_count));
 
+        hlist_del_init(&host->h_hash);
+
         nsm_unmonitor(host);
         nsm_release(host->h_nsmhandle);
 
@@ -216,6 +183,8 @@ nlm_destroy_host(struct nlm_host *host)
         if (clnt != NULL)
                 rpc_shutdown_client(clnt);
         kfree(host);
+
+        nrhosts--;
 }
 
 /**
@@ -249,12 +218,76 @@ struct nlm_host *nlmclnt_lookup_host(const struct sockaddr *sap,
                 .hostname_len   = strlen(hostname),
                 .noresvport     = noresvport,
         };
+        struct hlist_head *chain;
+        struct hlist_node *pos;
+        struct nlm_host *host;
+        struct nsm_handle *nsm = NULL;
 
         dprintk("lockd: %s(host='%s', vers=%u, proto=%s)\n", __func__,
                         (hostname ? hostname : "<none>"), version,
                         (protocol == IPPROTO_UDP ? "udp" : "tcp"));
 
-        return nlm_lookup_host(&ni);
+        mutex_lock(&nlm_host_mutex);
+
+        chain = &nlm_client_hosts[nlm_hash_address(sap)];
+        hlist_for_each_entry(host, pos, chain, h_hash) {
+                if (!rpc_cmp_addr(nlm_addr(host), sap))
+                        continue;
+
+                /* Same address. Share an NSM handle if we already have one */
+                if (nsm == NULL)
+                        nsm = host->h_nsmhandle;
+
+                if (host->h_proto != protocol)
+                        continue;
+                if (host->h_version != version)
+                        continue;
+
+                nlm_get_host(host);
+                dprintk("lockd: %s found host %s (%s)\n", __func__,
+                        host->h_name, host->h_addrbuf);
+                goto out;
+        }
+
+        host = nlm_alloc_host(&ni, nsm);
+        if (unlikely(host == NULL))
+                goto out;
+
+        hlist_add_head(&host->h_hash, chain);
+        nrhosts++;
+
+        dprintk("lockd: %s created host %s (%s)\n", __func__,
+                host->h_name, host->h_addrbuf);
+
+out:
+        mutex_unlock(&nlm_host_mutex);
+        return host;
+}
+
+/**
+ * nlmclnt_release_host - release client nlm_host
+ * @host: nlm_host to release
+ *
+ */
+void nlmclnt_release_host(struct nlm_host *host)
+{
+        if (host == NULL)
+                return;
+
+        dprintk("lockd: release client host %s\n", host->h_name);
+
+        BUG_ON(atomic_read(&host->h_count) < 0);
+        BUG_ON(host->h_server);
+
+        if (atomic_dec_and_test(&host->h_count)) {
+                BUG_ON(!list_empty(&host->h_lockowners));
+                BUG_ON(!list_empty(&host->h_granted));
+                BUG_ON(!list_empty(&host->h_reclaim));
+
+                mutex_lock(&nlm_host_mutex);
+                nlm_destroy_host_locked(host);
+                mutex_unlock(&nlm_host_mutex);
+        }
 }
 
 /**
@@ -279,12 +312,18 @@ struct nlm_host *nlmsvc_lookup_host(const struct svc_rqst *rqstp,
                                     const char *hostname,
                                     const size_t hostname_len)
 {
+        struct hlist_head *chain;
+        struct hlist_node *pos;
+        struct nlm_host *host = NULL;
+        struct nsm_handle *nsm = NULL;
         struct sockaddr_in sin = {
                 .sin_family     = AF_INET,
         };
         struct sockaddr_in6 sin6 = {
                 .sin6_family    = AF_INET6,
         };
+        struct sockaddr *src_sap;
+        size_t src_len = rqstp->rq_addrlen;
         struct nlm_lookup_host_info ni = {
                 .server         = 1,
                 .sap            = svc_addr(rqstp),
@@ -293,27 +332,91 @@ struct nlm_host *nlmsvc_lookup_host(const struct svc_rqst *rqstp,
                 .version        = rqstp->rq_vers,
                 .hostname       = hostname,
                 .hostname_len   = hostname_len,
-                .src_len        = rqstp->rq_addrlen,
         };
 
         dprintk("lockd: %s(host='%*s', vers=%u, proto=%s)\n", __func__,
                         (int)hostname_len, hostname, rqstp->rq_vers,
                         (rqstp->rq_prot == IPPROTO_UDP ? "udp" : "tcp"));
 
+        mutex_lock(&nlm_host_mutex);
+
         switch (ni.sap->sa_family) {
         case AF_INET:
                 sin.sin_addr.s_addr = rqstp->rq_daddr.addr.s_addr;
-                ni.src_sap = (struct sockaddr *)&sin;
+                src_sap = (struct sockaddr *)&sin;
                 break;
         case AF_INET6:
                 ipv6_addr_copy(&sin6.sin6_addr, &rqstp->rq_daddr.addr6);
-                ni.src_sap = (struct sockaddr *)&sin6;
+                src_sap = (struct sockaddr *)&sin6;
                 break;
         default:
-                return NULL;
+                dprintk("lockd: %s failed; unrecognized address family\n",
+                        __func__);
+                goto out;
         }
 
-        return nlm_lookup_host(&ni);
+        if (time_after_eq(jiffies, next_gc))
+                nlm_gc_hosts();
+
+        chain = &nlm_server_hosts[nlm_hash_address(ni.sap)];
+        hlist_for_each_entry(host, pos, chain, h_hash) {
+                if (!rpc_cmp_addr(nlm_addr(host), ni.sap))
+                        continue;
+
+                /* Same address. Share an NSM handle if we already have one */
+                if (nsm == NULL)
+                        nsm = host->h_nsmhandle;
+
+                if (host->h_proto != ni.protocol)
+                        continue;
+                if (host->h_version != ni.version)
+                        continue;
+                if (!rpc_cmp_addr(nlm_srcaddr(host), src_sap))
+                        continue;
+
+                /* Move to head of hash chain. */
+                hlist_del(&host->h_hash);
+                hlist_add_head(&host->h_hash, chain);
+
+                nlm_get_host(host);
+                dprintk("lockd: %s found host %s (%s)\n",
+                        __func__, host->h_name, host->h_addrbuf);
+                goto out;
+        }
+
+        host = nlm_alloc_host(&ni, nsm);
+        if (unlikely(host == NULL))
+                goto out;
+
+        memcpy(nlm_srcaddr(host), src_sap, src_len);
+        host->h_srcaddrlen = src_len;
+        hlist_add_head(&host->h_hash, chain);
+        nrhosts++;
+
+        dprintk("lockd: %s created host %s (%s)\n",
+                __func__, host->h_name, host->h_addrbuf);
+
+out:
+        mutex_unlock(&nlm_host_mutex);
+        return host;
+}
+
+/**
+ * nlmsvc_release_host - release server nlm_host
+ * @host: nlm_host to release
+ *
+ * Host is destroyed later in nlm_gc_host().
+ */
+void nlmsvc_release_host(struct nlm_host *host)
+{
+        if (host == NULL)
+                return;
+
+        dprintk("lockd: release server host %s\n", host->h_name);
+
+        BUG_ON(atomic_read(&host->h_count) < 0);
+        BUG_ON(!host->h_server);
+        atomic_dec(&host->h_count);
 }
 
 /*
@@ -413,20 +516,29 @@ struct nlm_host * nlm_get_host(struct nlm_host *host)
         return host;
 }
 
-/*
- * Release NLM host after use
- */
-void nlm_release_host(struct nlm_host *host)
+static struct nlm_host *next_host_state(struct hlist_head *cache,
+                                        struct nsm_handle *nsm,
+                                        const struct nlm_reboot *info)
 {
-        if (host != NULL) {
-                dprintk("lockd: release host %s\n", host->h_name);
-                BUG_ON(atomic_read(&host->h_count) < 0);
-                if (atomic_dec_and_test(&host->h_count)) {
-                        BUG_ON(!list_empty(&host->h_lockowners));
-                        BUG_ON(!list_empty(&host->h_granted));
-                        BUG_ON(!list_empty(&host->h_reclaim));
+        struct nlm_host *host;
+        struct hlist_head *chain;
+        struct hlist_node *pos;
+
+        mutex_lock(&nlm_host_mutex);
+        for_each_host(host, pos, chain, cache) {
+                if (host->h_nsmhandle == nsm
+                    && host->h_nsmstate != info->state) {
+                        host->h_nsmstate = info->state;
+                        host->h_state++;
+
+                        nlm_get_host(host);
+                        mutex_unlock(&nlm_host_mutex);
+                        return host;
                 }
         }
+
+        mutex_unlock(&nlm_host_mutex);
+        return NULL;
 }
 
 /**
@@ -438,8 +550,6 @@ void nlm_release_host(struct nlm_host *host)
  */
 void nlm_host_rebooted(const struct nlm_reboot *info)
 {
-        struct hlist_head *chain;
-        struct hlist_node *pos;
         struct nsm_handle *nsm;
         struct nlm_host *host;
 
@@ -452,32 +562,15 @@ void nlm_host_rebooted(const struct nlm_reboot *info)
          * lock for this.
          * To avoid processing a host several times, we match the nsmstate.
          */
-again:  mutex_lock(&nlm_host_mutex);
-        for (chain = nlm_hosts; chain < nlm_hosts + NLM_HOST_NRHASH; ++chain) {
-                hlist_for_each_entry(host, pos, chain, h_hash) {
-                        if (host->h_nsmhandle == nsm
-                         && host->h_nsmstate != info->state) {
-                                host->h_nsmstate = info->state;
-                                host->h_state++;
-
-                                nlm_get_host(host);
-                                mutex_unlock(&nlm_host_mutex);
-
-                                if (host->h_server) {
-                                        /* We're server for this guy, just ditch
-                                         * all the locks he held. */
-                                        nlmsvc_free_host_resources(host);
-                                } else {
-                                        /* He's the server, initiate lock recovery. */
-                                        nlmclnt_recovery(host);
-                                }
-
-                                nlm_release_host(host);
-                                goto again;
-                        }
-                }
+        while ((host = next_host_state(nlm_server_hosts, nsm, info)) != NULL) {
+                nlmsvc_free_host_resources(host);
+                nlmsvc_release_host(host);
         }
-        mutex_unlock(&nlm_host_mutex);
+        while ((host = next_host_state(nlm_client_hosts, nsm, info)) != NULL) {
+                nlmclnt_recovery(host);
+                nlmclnt_release_host(host);
+        }
+
         nsm_release(nsm);
 }
 
@@ -497,13 +590,11 @@ nlm_shutdown_hosts(void)
 
         /* First, make all hosts eligible for gc */
         dprintk("lockd: nuking all hosts...\n");
-        for (chain = nlm_hosts; chain < nlm_hosts + NLM_HOST_NRHASH; ++chain) {
-                hlist_for_each_entry(host, pos, chain, h_hash) {
-                        host->h_expires = jiffies - 1;
-                        if (host->h_rpcclnt) {
-                                rpc_shutdown_client(host->h_rpcclnt);
-                                host->h_rpcclnt = NULL;
-                        }
+        for_each_host(host, pos, chain, nlm_server_hosts) {
+                host->h_expires = jiffies - 1;
+                if (host->h_rpcclnt) {
+                        rpc_shutdown_client(host->h_rpcclnt);
+                        host->h_rpcclnt = NULL;
                 }
         }
 
@@ -512,15 +603,13 @@ nlm_shutdown_hosts(void)
         mutex_unlock(&nlm_host_mutex);
 
         /* complain if any hosts are left */
-        if (nrhosts) {
+        if (nrhosts != 0) {
                 printk(KERN_WARNING "lockd: couldn't shutdown host module!\n");
-                dprintk("lockd: %d hosts left:\n", nrhosts);
-                for (chain = nlm_hosts; chain < nlm_hosts + NLM_HOST_NRHASH; ++chain) {
-                        hlist_for_each_entry(host, pos, chain, h_hash) {
-                                dprintk("       %s (cnt %d use %d exp %ld)\n",
-                                        host->h_name, atomic_read(&host->h_count),
-                                        host->h_inuse, host->h_expires);
-                        }
+                dprintk("lockd: %lu hosts left:\n", nrhosts);
+                for_each_host(host, pos, chain, nlm_server_hosts) {
+                        dprintk("       %s (cnt %d use %d exp %ld)\n",
+                                host->h_name, atomic_read(&host->h_count),
+                                host->h_inuse, host->h_expires);
                 }
         }
 }
@@ -538,29 +627,22 @@ nlm_gc_hosts(void)
         struct nlm_host *host;
 
         dprintk("lockd: host garbage collection\n");
-        for (chain = nlm_hosts; chain < nlm_hosts + NLM_HOST_NRHASH; ++chain) {
-                hlist_for_each_entry(host, pos, chain, h_hash)
-                        host->h_inuse = 0;
-        }
+        for_each_host(host, pos, chain, nlm_server_hosts)
+                host->h_inuse = 0;
 
         /* Mark all hosts that hold locks, blocks or shares */
         nlmsvc_mark_resources();
 
-        for (chain = nlm_hosts; chain < nlm_hosts + NLM_HOST_NRHASH; ++chain) {
-                hlist_for_each_entry_safe(host, pos, next, chain, h_hash) {
-                        if (atomic_read(&host->h_count) || host->h_inuse
-                         || time_before(jiffies, host->h_expires)) {
-                                dprintk("nlm_gc_hosts skipping %s (cnt %d use %d exp %ld)\n",
-                                        host->h_name, atomic_read(&host->h_count),
-                                        host->h_inuse, host->h_expires);
-                                continue;
-                        }
-                        dprintk("lockd: delete host %s\n", host->h_name);
-                        hlist_del_init(&host->h_hash);
-
-                        nlm_destroy_host(host);
-                        nrhosts--;
+        for_each_host_safe(host, pos, next, chain, nlm_server_hosts) {
+                if (atomic_read(&host->h_count) || host->h_inuse
+                 || time_before(jiffies, host->h_expires)) {
+                        dprintk("nlm_gc_hosts skipping %s "
+                                "(cnt %d use %d exp %ld)\n",
+                                host->h_name, atomic_read(&host->h_count),
+                                host->h_inuse, host->h_expires);
+                        continue;
                 }
+                nlm_destroy_host_locked(host);
         }
 
         next_gc = jiffies + NLM_HOST_COLLECT;