[PATCH] knfsd: be more selective in which sockets lockd listens on

Currently lockd listens on UDP always, and TCP if CONFIG_NFSD_TCP is set.

However as lockd performs services of the client as well, this is a problem.
If CONFIG_NfSD_TCP is not set, and a tcp mount is used, the server will not be
able to call back to lockd.

So:
 - add an option to lockd_up saying which protocol is needed
 - Always open sockets for which an explicit port was given, otherwise
   only open a socket of the type required
 - Change nfsd to do one lockd_up per socket rather than one per thread.

This
 - removes the dependancy on CONFIG_NFSD_TCP
 - means that lockd may open sockets other than at startup
 - means that lockd will *not* listen on UDP if the only
   mounts are TCP mount (and nfsd hasn't started).

The latter is the only one that concerns me at all - I don't know if this
might be a problem with some servers.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/fs/lockd/clntlock.c b/fs/lockd/clntlock.c
index f95cc3f..6abb465 100644 (file)
--- a/fs/lockd/clntlock.c
+++ b/fs/lockd/clntlock.c
@@ -202,7 +202,7 @@ reclaimer(void *ptr)
        /* This one ensures that our parent doesn't terminate while the
         * reclaim is in progress */
        lock_kernel();
-       lockd_up();
+       lockd_up(0);
 
        nlmclnt_prepare_reclaim(host);
        /* First, reclaim all locks that have been marked. */

diff --git a/fs/lockd/svc.c b/fs/lockd/svc.c
index 13feba4..8d19de6 100644 (file)
--- a/fs/lockd/svc.c
+++ b/fs/lockd/svc.c
@@ -31,6 +31,7 @@
 #include <linux/sunrpc/clnt.h>
 #include <linux/sunrpc/svc.h>
 #include <linux/sunrpc/svcsock.h>
+#include <net/ip.h>
 #include <linux/lockd/lockd.h>
 #include <linux/nfs.h>
 
@@ -46,6 +47,7 @@ EXPORT_SYMBOL(nlmsvc_ops);
 static DEFINE_MUTEX(nlmsvc_mutex);
 static unsigned int            nlmsvc_users;
 static pid_t                   nlmsvc_pid;
+static struct svc_serv         *nlmsvc_serv;
 int                            nlmsvc_grace_period;
 unsigned long                  nlmsvc_timeout;
 
@@ -112,6 +114,7 @@ lockd(struct svc_rqst *rqstp)
         * Let our maker know we're running.
         */
        nlmsvc_pid = current->pid;
+       nlmsvc_serv = serv;
        complete(&lockd_start_done);
 
        daemonize("lockd");
@@ -189,6 +192,7 @@ lockd(struct svc_rqst *rqstp)
                        nlmsvc_invalidate_all();
                nlm_shutdown_hosts();
                nlmsvc_pid = 0;
+               nlmsvc_serv = NULL;
        } else
                printk(KERN_DEBUG
                        "lockd: new process, skipping host shutdown\n");
@@ -205,11 +209,42 @@ lockd(struct svc_rqst *rqstp)
        module_put_and_exit(0);
 }
 
+
+static int find_socket(struct svc_serv *serv, int proto)
+{
+       struct svc_sock *svsk;
+       int found = 0;
+       list_for_each_entry(svsk, &serv->sv_permsocks, sk_list)
+               if (svsk->sk_sk->sk_protocol == proto) {
+                       found = 1;
+                       break;
+               }
+       return found;
+}
+
+static int make_socks(struct svc_serv *serv, int proto)
+{
+       /* Make any sockets that are needed but not present.
+        * If nlm_udpport or nlm_tcpport were set as module
+        * options, make those sockets unconditionally
+        */
+       int err = 0;
+       if (proto == IPPROTO_UDP || nlm_udpport)
+               if (!find_socket(serv, IPPROTO_UDP))
+                       err = svc_makesock(serv, IPPROTO_UDP, nlm_udpport);
+       if (err)
+               return err;
+       if (proto == IPPROTO_TCP || nlm_tcpport)
+               if (!find_socket(serv, IPPROTO_TCP))
+                       err= svc_makesock(serv, IPPROTO_TCP, nlm_tcpport);
+       return err;
+}
+
 /*
  * Bring up the lockd process if it's not already up.
  */
 int
-lockd_up(void)
+lockd_up(int proto) /* Maybe add a 'family' option when IPv6 is supported ?? */
 {
        static int              warned;
        struct svc_serv *       serv;
@@ -224,8 +259,10 @@ lockd_up(void)
        /*
         * Check whether we're already up and running.
         */
-       if (nlmsvc_pid)
+       if (nlmsvc_pid) {
+               error = make_socks(nlmsvc_serv, proto);
                goto out;
+       }
 
        /*
         * Sanity check: if there's no pid,
@@ -242,11 +279,7 @@ lockd_up(void)
                goto out;
        }
 
-       if ((error = svc_makesock(serv, IPPROTO_UDP, nlm_udpport)) < 0 
-#ifdef CONFIG_NFSD_TCP
-        || (error = svc_makesock(serv, IPPROTO_TCP, nlm_tcpport)) < 0
-#endif
-               ) {
+       if ((error = make_socks(serv, proto)) < 0) {
                if (warned++ == 0) 
                        printk(KERN_WARNING
                                "lockd_up: makesock failed, error=%d\n", error);

diff --git a/fs/nfs/client.c b/fs/nfs/client.c
index ec1938d..8106f3b 100644 (file)
--- a/fs/nfs/client.c
+++ b/fs/nfs/client.c
@@ -460,7 +460,8 @@ static int nfs_start_lockd(struct nfs_server *server)
                goto out;
        if (server->flags & NFS_MOUNT_NONLM)
                goto out;
-       error = lockd_up();
+       error = lockd_up((server->flags & NFS_MOUNT_TCP) ?
+                       IPPROTO_TCP : IPPROTO_UDP);
        if (error < 0)
                server->flags |= NFS_MOUNT_NONLM;
        else

diff --git a/fs/nfsd/nfssvc.c b/fs/nfsd/nfssvc.c
index c52c999..0339b4d 100644 (file)
--- a/fs/nfsd/nfssvc.c
+++ b/fs/nfsd/nfssvc.c
@@ -134,6 +134,9 @@ static int killsig; /* signal that was used to kill last nfsd */
 static void nfsd_last_thread(struct svc_serv *serv)
 {
        /* When last nfsd thread exits we need to do some clean-up */
+       struct svc_sock *svsk;
+       list_for_each_entry(svsk, &serv->sv_permsocks, sk_list)
+               lockd_down();
        nfsd_serv = NULL;
        nfsd_racache_shutdown();
        nfs4_state_shutdown();
@@ -218,11 +221,16 @@ nfsd_svc(unsigned short port, int nrservs)
                error = svc_makesock(nfsd_serv, IPPROTO_UDP, port);
                if (error < 0)
                        goto failure;
-
+               error = lockd_up(IPPROTO_UDP);
+               if (error < 0)
+                       goto failure;
 #ifdef CONFIG_NFSD_TCP
                error = svc_makesock(nfsd_serv, IPPROTO_TCP, port);
                if (error < 0)
                        goto failure;
+               error = lockd_up(IPPROTO_TCP);
+               if (error < 0)
+                       goto failure;
 #endif
                do_gettimeofday(&nfssvc_boot);          /* record boot time */
        } else
@@ -306,8 +314,6 @@ nfsd(struct svc_rqst *rqstp)
 
        nfsdstats.th_cnt++;
 
-       lockd_up();                             /* start lockd */
-
        me.task = current;
        list_add(&me.list, &nfsd_list);
 
@@ -364,13 +370,11 @@ nfsd(struct svc_rqst *rqstp)
                                break;
                killsig = signo;
        }
-       /* Clear signals before calling lockd_down() and svc_exit_thread() */
+       /* Clear signals before calling svc_exit_thread() */
        flush_signals(current);
 
        lock_kernel();
 
-       /* Release lockd */
-       lockd_down();
        list_del(&me.list);
        nfsdstats.th_cnt --;
 

diff --git a/include/linux/lockd/bind.h b/include/linux/lockd/bind.h
index b054deb..81e3a18 100644 (file)
--- a/include/linux/lockd/bind.h
+++ b/include/linux/lockd/bind.h
@@ -30,7 +30,7 @@ extern struct nlmsvc_binding *        nlmsvc_ops;
  * Functions exported by the lockd module
  */
 extern int     nlmclnt_proc(struct inode *, int, struct file_lock *);
-extern int     lockd_up(void);
+extern int     lockd_up(int proto);
 extern void    lockd_down(void);
 
 #endif /* LINUX_LOCKD_BIND_H */