[PATCH 006 of 19] knfsd: lockd: Make nlm_host_rebooted use the nsm_handle

NeilBrown
2006-09-01T04:38:58Z

From: Olaf Kirch <okir@suse.de>

This patch makes the SM_NOTIFY handling understand and use
the nsm_handle.

To make it a bit clear what is happening:
nlmclent_prepare_reclaim and nlmclnt_finish_reclaim
get open-coded into 'reclaimer'
The result is tidied up.
Then some of that functionality is moved out into
nlm_host_rebooted (which calls nlmclnt_recovery which
starts a thread which runs reclaimer).

Also host_rebooted now finds an nsm_handle rather than a
host, then then iterates over all hosts and deals with
each host that shares that nsm_handle.

Signed-off-by: Olaf Kirch <okir@suse.de>
Signed-off-by: Neil Brown <neilb@suse.de>

### Diffstat output
./fs/lockd/clntlock.c | 55 ++++++++++++-----------------------
./fs/lockd/host.c | 65 ++++++++++++++++++++++++++++++------------
./fs/lockd/svc4proc.c | 2 -
./fs/lockd/svcproc.c | 2 -
./include/linux/lockd/lockd.h | 4 +-
5 files changed, 70 insertions(+), 58 deletions(-)

diff .prev/fs/lockd/clntlock.c ./fs/lockd/clntlock.c
--- .prev/fs/lockd/clntlock.c 2006-08-31 17:00:03.000000000 +1000
+++ ./fs/lockd/clntlock.c 2006-08-31 17:02:23.000000000 +1000
@@ -144,43 +144,12 @@ u32 nlmclnt_grant(const struct sockaddr_
*/

/*
- * Someone has sent us an SM_NOTIFY. Ensure we bind to the new port number,
- * that we mark locks for reclaiming, and that we bump the pseudo NSM state.
- */
-static void nlmclnt_prepare_reclaim(struct nlm_host *host)
-{
- down_write(&host->h_rwsem);
- if (host->h_nsmhandle)
- host->h_nsmhandle->sm_monitored = 0;
- host->h_state++;
- host->h_nextrebind = 0;
- nlm_rebind_host(host);
-
- /*
- * Mark the locks for reclaiming.
- */
- list_splice_init(&host->h_granted, &host->h_reclaim);
-
- dprintk("NLM: reclaiming locks for host %s\n", host->h_name);
-}
-
-static void nlmclnt_finish_reclaim(struct nlm_host *host)
-{
- host->h_reclaiming = 0;
- up_write(&host->h_rwsem);
- dprintk("NLM: done reclaiming locks for host %s", host->h_name);
-}
-
-/*
* Reclaim all locks on server host. We do this by spawning a separate
* reclaimer thread.
*/
void
-nlmclnt_recovery(struct nlm_host *host, u32 newstate)
+nlmclnt_recovery(struct nlm_host *host)
{
- if (host->h_nsmstate == newstate)
- return;
- host->h_nsmstate = newstate;
if (!host->h_reclaiming++) {
nlm_get_host(host);
__module_get(THIS_MODULE);
@@ -200,18 +169,30 @@ reclaimer(void *ptr)
daemonize("%s-reclaim", host->h_name);
allow_signal(SIGKILL);

+ down_write(&host->h_rwsem);
+
/* This one ensures that our parent doesn't terminate while the
* reclaim is in progress */
lock_kernel();
lockd_up(0); /* note: this cannot fail as lockd is already running */

- nlmclnt_prepare_reclaim(host);
- /* First, reclaim all locks that have been marked. */
+ dprintk("lockd: reclaiming locks for host %s", host->h_name);
+
restart:
nsmstate = host->h_nsmstate;
+
+ /* Force a portmap getport - the peer's lockd will
+ * most likely end up on a different port.
+ */
+ host->h_nextrebind = 0;
+ nlm_rebind_host(host);
+
+ /* First, reclaim all locks that have been granted. */
+ list_splice_init(&host->h_granted, &host->h_reclaim);
list_for_each_entry_safe(fl, next, &host->h_reclaim, fl_u.nfs_fl.list) {
list_del_init(&fl->fl_u.nfs_fl.list);

+ /* Why are we leaking memory here? --okir */
if (signalled())
continue;
if (nlmclnt_reclaim(host, fl) != 0)
@@ -219,11 +200,13 @@ restart:
list_add_tail(&fl->fl_u.nfs_fl.list, &host->h_granted);
if (host->h_nsmstate != nsmstate) {
/* Argh! The server rebooted again! */
- list_splice_init(&host->h_granted, &host->h_reclaim);
goto restart;
}
}
- nlmclnt_finish_reclaim(host);
+
+ host->h_reclaiming = 0;
+ up_write(&host->h_rwsem);
+ dprintk("NLM: done reclaiming locks for host %s", host->h_name);

/* Now, wake up all processes that sleep on a blocked lock */
list_for_each_entry(block, &nlm_blocked, b_list) {

diff .prev/fs/lockd/host.c ./fs/lockd/host.c
--- .prev/fs/lockd/host.c 2006-08-31 17:01:00.000000000 +1000
+++ ./fs/lockd/host.c 2006-08-31 17:02:03.000000000 +1000
@@ -290,28 +290,57 @@ void nlm_release_host(struct nlm_host *h
* has rebooted.
* Release all resources held by that peer.
*/
-void nlm_host_rebooted(const struct sockaddr_in *sin, const struct nlm_reboot *argp)
-{
- struct nlm_host *host;
- int server;
+void nlm_host_rebooted(const struct sockaddr_in *sin,
+ const char *hostname, int hostname_len,
+ u32 new_state)
+{
+ struct nsm_handle *nsm;
+ struct nlm_host *host, **hp;
+ int hash;

- /* Obtain the host pointer for this NFS server and try to
- * reclaim all locks we hold on this server.
- */
- server = (argp->proto & 1)? 1 : 0;
- host = nlm_lookup_host(server, sin, argp->proto >> 1, argp->vers,
- argp->mon, argp->len);
- if (host == NULL)
+ dprintk("lockd: nlm_host_rebooted(%s, %u.%u.%u.%u)\n",
+ hostname, NIPQUAD(sin->sin_addr));
+
+ /* Find the NSM handle for this peer */
+ if (!(nsm = __nsm_find(sin, hostname, hostname_len, 0)))
return;

- if (server == 0) {
- /* We are client, he's the server: try to reclaim all locks. */
- nlmclnt_recovery(host, argp->state);
- } else {
- /* He's the client, we're the server: delete all locks held by the client */
- nlmsvc_free_host_resources(host);
+ /* When reclaiming locks on this peer, make sure that
+ * we set up a new notification */
+ nsm->sm_monitored = 0;
+
+ /* Mark all hosts tied to this NSM state as having rebooted.
+ * We run the loop repeatedly, because we drop the host table
+ * lock for this.
+ * To avoid processing a host several times, we match the nsmstate.
+ */
+again: mutex_lock(&nlm_host_mutex);
+ for (hash = 0; hash < NLM_HOST_NRHASH; hash++) {
+ for (hp = &nlm_hosts[hash]; (host = *hp); hp = &host->h_next) {
+ if (host->h_nsmhandle == nsm
+ && host->h_nsmstate != new_state) {
+ host->h_nsmstate = new_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;
+ }
+ }
}
- nlm_release_host(host);
+
+ mutex_unlock(&nlm_host_mutex);
}

/*

diff .prev/fs/lockd/svc4proc.c ./fs/lockd/svc4proc.c
--- .prev/fs/lockd/svc4proc.c 2006-08-31 16:59:53.000000000 +1000
+++ ./fs/lockd/svc4proc.c 2006-08-31 17:02:03.000000000 +1000
@@ -438,7 +438,7 @@ nlm4svc_proc_sm_notify(struct svc_rqst *
*/
memset(&saddr, 0, sizeof(saddr));
saddr.sin_addr.s_addr = argp->addr;
- nlm_host_rebooted(&saddr, argp);
+ nlm_host_rebooted(&saddr, argp->mon, argp->len, argp->state);

return rpc_success;
}

diff .prev/fs/lockd/svcproc.c ./fs/lockd/svcproc.c
--- .prev/fs/lockd/svcproc.c 2006-08-31 16:59:39.000000000 +1000
+++ ./fs/lockd/svcproc.c 2006-08-31 17:02:03.000000000 +1000
@@ -467,7 +467,7 @@ nlmsvc_proc_sm_notify(struct svc_rqst *r
*/
memset(&saddr, 0, sizeof(saddr));
saddr.sin_addr.s_addr = argp->addr;
- nlm_host_rebooted(&saddr, argp);
+ nlm_host_rebooted(&saddr, argp->mon, argp->len, argp->state);

return rpc_success;
}

diff .prev/include/linux/lockd/lockd.h ./include/linux/lockd/lockd.h
--- .prev/include/linux/lockd/lockd.h 2006-08-31 17:00:03.000000000 +1000
+++ ./include/linux/lockd/lockd.h 2006-08-31 17:02:03.000000000 +1000
@@ -164,7 +164,7 @@ struct nlm_wait * nlmclnt_prepare_block(
void nlmclnt_finish_block(struct nlm_wait *block);
int nlmclnt_block(struct nlm_wait *block, struct nlm_rqst *req, long timeout);
u32 nlmclnt_grant(const struct sockaddr_in *addr, const struct nlm_lock *);
-void nlmclnt_recovery(struct nlm_host *, u32);
+void nlmclnt_recovery(struct nlm_host *);
int nlmclnt_reclaim(struct nlm_host *, struct file_lock *);

/*
@@ -179,7 +179,7 @@ struct nlm_host * nlm_get_host(struct nl
void nlm_release_host(struct nlm_host *);
void nlm_shutdown_hosts(void);
extern struct nlm_host *nlm_find_client(void);
-extern void nlm_host_rebooted(const struct sockaddr_in *, const struct nlm_reboot *);
+extern void nlm_host_rebooted(const struct sockaddr_in *, const char *, int, u32);
struct nsm_handle *nsm_find(const struct sockaddr_in *, const char *, int);
void nsm_release(struct nsm_handle *);