NLM: Convert nlm_lookup_host() to use a single argument

The nlm_lookup_host() function already has a large number of arguments,
and I'm about to add a few more.  As a clean up, convert the function
to use a single data structure argument.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

1 files changed, 56 insertions, 30 deletions

diff --git a/fs/lockd/host.c b/fs/lockd/host.c
index be8f19d53183..3c4dc33c1bea 100644
--- a/fs/lockd/host.c
+++ b/fs/lockd/host.c
@@ -38,6 +38,17 @@ static struct nsm_handle	*nsm_find(const struct sockaddr *sap,
                                                 const size_t hostname_len,
                                                 const int create);
 
+struct nlm_lookup_host_info {
+        const int               server;         /* search for server|client */
+        const struct sockaddr_in *sin;          /* address to search for */
+        const unsigned short    protocol;       /* transport to search for*/
+        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_in *src_sin;      /* our address (optional) */
+        const size_t            src_len;        /* it's length */
+};
+
 /*
  * Hash function must work well on big- and little-endian platforms
  */
@@ -121,23 +132,13 @@ static void nlm_display_address(const struct sockaddr *sap,
 /*
  * Common host lookup routine for server & client
  */
-static struct nlm_host *nlm_lookup_host(int server,
-                                        const struct sockaddr_in *sin,
-                                        int proto, u32 version,
-                                        const char *hostname,
-                                        unsigned int hostname_len,
-                                        const struct sockaddr_in *ssin)
+static struct nlm_host *nlm_lookup_host(struct nlm_lookup_host_info *ni)
 {
         struct hlist_head *chain;
         struct hlist_node *pos;
         struct nlm_host *host;
         struct nsm_handle *nsm = NULL;
 
-        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>");
-
         mutex_lock(&nlm_host_mutex);
 
         if (time_after_eq(jiffies, next_gc))
@@ -150,22 +151,23 @@ 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[nlm_hash_address((struct sockaddr *)sin)];
+        chain = &nlm_hosts[nlm_hash_address((struct sockaddr *)ni->sin)];
         hlist_for_each_entry(host, pos, chain, h_hash) {
-                if (!nlm_cmp_addr(nlm_addr(host), (struct sockaddr *)sin))
+                if (!nlm_cmp_addr(nlm_addr(host), (struct sockaddr *)ni->sin))
                         continue;
 
                 /* See if we have an NSM handle for this client */
                 if (!nsm)
                         nsm = host->h_nsmhandle;
 
-                if (host->h_proto != proto)
+                if (host->h_proto != ni->protocol)
                         continue;
-                if (host->h_version != version)
+                if (host->h_version != ni->version)
                         continue;
-                if (host->h_server != server)
+                if (host->h_server != ni->server)
                         continue;
-                if (!nlm_cmp_addr(nlm_srcaddr(host), (struct sockaddr *)ssin))
+                if (!nlm_cmp_addr(nlm_srcaddr(host),
+                                        (struct sockaddr *)ni->src_sin))
                         continue;
 
                 /* Move to head of hash chain. */
@@ -186,8 +188,9 @@ static struct nlm_host *nlm_lookup_host(int server,
                 atomic_inc(&nsm->sm_count);
         else {
                 host = NULL;
-                nsm = nsm_find((struct sockaddr *)sin, sizeof(*sin),
-                                hostname, hostname_len, 1);
+                nsm = nsm_find((struct sockaddr *)ni->sin,
+                                sizeof(struct sockaddr_in),
+                                ni->hostname, ni->hostname_len, 1);
                 if (!nsm) {
                         dprintk("lockd: nlm_lookup_host failed; "
                                 "no nsm handle\n");
@@ -202,12 +205,12 @@ static struct nlm_host *nlm_lookup_host(int server,
                 goto out;
         }
         host->h_name       = nsm->sm_name;
-        memcpy(nlm_addr(host), sin, sizeof(*sin));
-        host->h_addrlen = sizeof(*sin);
+        memcpy(nlm_addr(host), ni->sin, sizeof(struct sockaddr_in));
+        host->h_addrlen = sizeof(struct sockaddr_in);
         nlm_clear_port(nlm_addr(host));
-        memcpy(nlm_srcaddr(host), ssin, sizeof(*ssin));
-        host->h_version    = version;
-        host->h_proto      = proto;
+        memcpy(nlm_srcaddr(host), ni->src_sin, sizeof(struct sockaddr_in));
+        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;
@@ -218,7 +221,7 @@ static struct nlm_host *nlm_lookup_host(int server,
         host->h_state      = 0;                 /* pseudo NSM state */
         host->h_nsmstate   = 0;                 /* real NSM state */
         host->h_nsmhandle  = nsm;
-        host->h_server     = server;
+        host->h_server     = ni->server;
         hlist_add_head(&host->h_hash, chain);
         INIT_LIST_HEAD(&host->h_lockowners);
         spin_lock_init(&host->h_lock);
@@ -273,9 +276,21 @@ struct nlm_host *nlmclnt_lookup_host(const struct sockaddr_in *sin,
         const struct sockaddr_in source = {
                 .sin_family     = AF_UNSPEC,
         };
+        struct nlm_lookup_host_info ni = {
+                .server         = 0,
+                .sin            = sin,
+                .protocol       = proto,
+                .version        = version,
+                .hostname       = hostname,
+                .hostname_len   = hostname_len,
+                .src_sin        = &source,
+        };
 
-        return nlm_lookup_host(0, sin, proto, version,
-                               hostname, hostname_len, &source);
+        dprintk("lockd: %s(host='%s', vers=%u, proto=%s)\n", __func__,
+                        (hostname ? hostname : "<none>"), version,
+                        (proto == IPPROTO_UDP ? "udp" : "tcp"));
+
+        return nlm_lookup_host(&ni);
 }
 
 /*
@@ -289,10 +304,21 @@ nlmsvc_lookup_host(struct svc_rqst *rqstp,
                 .sin_family     = AF_INET,
                 .sin_addr       = rqstp->rq_daddr.addr,
         };
+        struct nlm_lookup_host_info ni = {
+                .server         = 1,
+                .sin            = svc_addr_in(rqstp),
+                .protocol       = rqstp->rq_prot,
+                .version        = rqstp->rq_vers,
+                .hostname       = hostname,
+                .hostname_len   = hostname_len,
+                .src_sin        = &source,
+        };
+
+        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"));
 
-        return nlm_lookup_host(1, svc_addr_in(rqstp),
-                               rqstp->rq_prot, rqstp->rq_vers,
-                               hostname, hostname_len, &source);
+        return nlm_lookup_host(&ni);
 }
 
 /*