[PATCH] knfsd: add a callback for when last rpc thread finishes

nfsd has some cleanup that it wants to do when the last thread exits, and
there will shortly be some more.  So collect this all into one place and
define a callback for an rpc service to call when the service is about to be
destroyed.

[akpm@osdl.org: cleanups, build fix]
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

5 files changed, 33 insertions, 26 deletions

diff --git a/fs/lockd/svc.c b/fs/lockd/svc.c
index 9a991b52c647..13feba45030e 100644
--- a/fs/lockd/svc.c
+++ b/fs/lockd/svc.c
@@ -236,7 +236,7 @@ lockd_up(void)
                         "lockd_up: no pid, %d users??\n", nlmsvc_users);
 
         error = -ENOMEM;
-        serv = svc_create(&nlmsvc_program, LOCKD_BUFSIZE);
+        serv = svc_create(&nlmsvc_program, LOCKD_BUFSIZE, NULL);
         if (!serv) {
                 printk(KERN_WARNING "lockd_up: create service failed\n");
                 goto out;
diff --git a/fs/nfs/callback.c b/fs/nfs/callback.c
index a3ee11364db0..e244cdc7afab 100644
--- a/fs/nfs/callback.c
+++ b/fs/nfs/callback.c
@@ -116,7 +116,7 @@ int nfs_callback_up(void)
                 goto out;
         init_completion(&nfs_callback_info.started);
         init_completion(&nfs_callback_info.stopped);
-        serv = svc_create(&nfs4_callback_program, NFS4_CALLBACK_BUFSIZE);
+        serv = svc_create(&nfs4_callback_program, NFS4_CALLBACK_BUFSIZE, NULL);
         ret = -ENOMEM;
         if (!serv)
                 goto out_err;
diff --git a/fs/nfsd/nfssvc.c b/fs/nfsd/nfssvc.c
index ec1decf29bab..c52c99964a4c 100644
--- a/fs/nfsd/nfssvc.c
+++ b/fs/nfsd/nfssvc.c
@@ -130,11 +130,25 @@ int nfsd_nrthreads(void)
                 return nfsd_serv->sv_nrthreads;
 }
 
+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 */
+        nfsd_serv = NULL;
+        nfsd_racache_shutdown();
+        nfs4_state_shutdown();
+
+        printk(KERN_WARNING "nfsd: last server has exited\n");
+        if (killsig != SIG_NOCLEAN) {
+                printk(KERN_WARNING "nfsd: unexporting all filesystems\n");
+                nfsd_export_flush();
+        }
+}
 int
 nfsd_svc(unsigned short port, int nrservs)
 {
         int     error;
-        int     none_left, found_one, i;
+        int     found_one, i;
         struct list_head *victim;
         
         lock_kernel();
@@ -197,7 +211,8 @@ nfsd_svc(unsigned short port, int nrservs)
 
                 atomic_set(&nfsd_busy, 0);
                 error = -ENOMEM;
-                nfsd_serv = svc_create(&nfsd_program, NFSD_BUFSIZE);
+                nfsd_serv = svc_create(&nfsd_program, NFSD_BUFSIZE,
+                                       nfsd_last_thread);
                 if (nfsd_serv == NULL)
                         goto out;
                 error = svc_makesock(nfsd_serv, IPPROTO_UDP, port);
@@ -231,13 +246,7 @@ nfsd_svc(unsigned short port, int nrservs)
                 nrservs++;
         }
  failure:
-        none_left = (nfsd_serv->sv_nrthreads == 1);
         svc_destroy(nfsd_serv);         /* Release server */
-        if (none_left) {
-                nfsd_serv = NULL;
-                nfsd_racache_shutdown();
-                nfs4_state_shutdown();
-        }
  out:
         unlock_kernel();
         return error;
@@ -353,7 +362,7 @@ nfsd(struct svc_rqst *rqstp)
                         if (sigismember(&current->pending.signal, signo) &&
                             !sigismember(&current->blocked, signo))
                                 break;
-                err = signo;
+                killsig = signo;
         }
         /* Clear signals before calling lockd_down() and svc_exit_thread() */
         flush_signals(current);
@@ -362,19 +371,6 @@ nfsd(struct svc_rqst *rqstp)
 
         /* Release lockd */
         lockd_down();
-
-        /* Check if this is last thread */
-        if (serv->sv_nrthreads==1) {
-                
-                printk(KERN_WARNING "nfsd: last server has exited\n");
-                if (err != SIG_NOCLEAN) {
-                        printk(KERN_WARNING "nfsd: unexporting all filesystems\n");
-                        nfsd_export_flush();
-                }
-                nfsd_serv = NULL;
-                nfsd_racache_shutdown();        /* release read-ahead cache */
-                nfs4_state_shutdown();
-        }
         list_del(&me.list);
         nfsdstats.th_cnt --;
 
diff --git a/include/linux/sunrpc/svc.h b/include/linux/sunrpc/svc.h
index 73140ee5c638..bff5e9b486c2 100644
--- a/include/linux/sunrpc/svc.h
+++ b/include/linux/sunrpc/svc.h
@@ -42,6 +42,11 @@ struct svc_serv {
         int                     sv_tmpcnt;      /* count of temporary sockets */
 
         char *                  sv_name;        /* service name */
+
+        void                    (*sv_shutdown)(struct svc_serv *serv);
+                                                /* Callback to use when last thread
+                                                 * exits.
+                                                 */
 };
 
 /*
@@ -328,7 +333,8 @@ typedef void		(*svc_thread_fn)(struct svc_rqst *);
 /*
  * Function prototypes.
  */
-struct svc_serv *  svc_create(struct svc_program *, unsigned int);
+struct svc_serv *  svc_create(struct svc_program *, unsigned int,
+                              void (*shutdown)(struct svc_serv*));
 int                svc_create_thread(svc_thread_fn, struct svc_serv *);
 void               svc_exit_thread(struct svc_rqst *);
 void               svc_destroy(struct svc_serv *);
diff --git a/net/sunrpc/svc.c b/net/sunrpc/svc.c
index 44b8d9d4c18a..f5aee4c61676 100644
--- a/net/sunrpc/svc.c
+++ b/net/sunrpc/svc.c
@@ -26,7 +26,8 @@
  * Create an RPC service
  */
 struct svc_serv *
-svc_create(struct svc_program *prog, unsigned int bufsize)
+svc_create(struct svc_program *prog, unsigned int bufsize,
+           void (*shutdown)(struct svc_serv *serv))
 {
         struct svc_serv *serv;
         int vers;
@@ -39,6 +40,7 @@ svc_create(struct svc_program *prog, unsigned int bufsize)
         serv->sv_nrthreads = 1;
         serv->sv_stats     = prog->pg_stats;
         serv->sv_bufsz     = bufsize? bufsize : 4096;
+        serv->sv_shutdown  = shutdown;
         xdrsize = 0;
         while (prog) {
                 prog->pg_lovers = prog->pg_nvers-1;
@@ -91,6 +93,9 @@ svc_destroy(struct svc_serv *serv)
                                   sk_list);
                 svc_delete_socket(svsk);
         }
+        if (serv->sv_shutdown)
+                serv->sv_shutdown(serv);
+
         while (!list_empty(&serv->sv_permsocks)) {
                 svsk = list_entry(serv->sv_permsocks.next,
                                   struct svc_sock,