From: Olaf Kirch Date: Wed, 4 Oct 2006 09:15:53 +0000 (-0700) Subject: [PATCH] knfsd: lockd: introduce nsm_handle X-Git-Tag: v2.6.19-rc1~127 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=8dead0dbd478f35fd943f3719591e5af1ac0950d;p=linux-2.6 [PATCH] knfsd: lockd: introduce nsm_handle This patch introduces the nsm_handle, which is shared by all nlm_host objects referring to the same client. With this patch applied, all nlm_hosts from the same address will share the same nsm_handle. A future patch will add sharing by name. Note: this patch changes h_name so that it is no longer guaranteed to be an IP address of the host. When the host represents an NFS server, h_name will be the name passed in the mount call. When the host represents a client, h_name will be the name presented in the lock request received from the client. A h_name is only used for printing informational messages, this change should not be significant. Signed-off-by: Olaf Kirch Signed-off-by: Neil Brown Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/fs/lockd/clntlock.c b/fs/lockd/clntlock.c index 87e1d03e82..54e63ddef0 100644 --- a/fs/lockd/clntlock.c +++ b/fs/lockd/clntlock.c @@ -150,7 +150,8 @@ u32 nlmclnt_grant(const struct sockaddr_in *addr, const struct nlm_lock *lock) static void nlmclnt_prepare_reclaim(struct nlm_host *host) { down_write(&host->h_rwsem); - host->h_monitored = 0; + if (host->h_nsmhandle) + host->h_nsmhandle->sm_monitored = 0; host->h_state++; host->h_nextrebind = 0; nlm_rebind_host(host); diff --git a/fs/lockd/host.c b/fs/lockd/host.c index 481ce7ee10..0bf4afb71d 100644 --- a/fs/lockd/host.c +++ b/fs/lockd/host.c @@ -34,6 +34,8 @@ static DEFINE_MUTEX(nlm_host_mutex); static void nlm_gc_hosts(void); +static struct nsm_handle * __nsm_find(const struct sockaddr_in *, + const char *, int, int); /* * Find an NLM server handle in the cache. If there is none, create it. @@ -68,7 +70,7 @@ nlm_lookup_host(int server, const struct sockaddr_in *sin, int hostname_len) { struct nlm_host *host, **hp; - u32 addr; + struct nsm_handle *nsm = NULL; int hash; dprintk("lockd: nlm_lookup_host(%u.%u.%u.%u, p=%d, v=%d, my role=%s, name=%.*s)\n", @@ -86,7 +88,21 @@ nlm_lookup_host(int server, const struct sockaddr_in *sin, 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. + */ for (hp = &nlm_hosts[hash]; (host = *hp) != 0; hp = &host->h_next) { + if (!nlm_cmp_addr(&host->h_addr, sin)) + continue; + + /* See if we have an NSM handle for this client */ + if (!nsm && (nsm = host->h_nsmhandle) != 0) + atomic_inc(&nsm->sm_count); + if (host->h_proto != proto) continue; if (host->h_version != version) @@ -94,7 +110,7 @@ nlm_lookup_host(int server, const struct sockaddr_in *sin, if (host->h_server != server) continue; - if (nlm_cmp_addr(&host->h_addr, sin)) { + { if (hp != nlm_hosts + hash) { *hp = host->h_next; host->h_next = nlm_hosts[hash]; @@ -106,16 +122,18 @@ nlm_lookup_host(int server, const struct sockaddr_in *sin, } } - /* Ooops, no host found, create it */ - dprintk("lockd: creating host entry\n"); + /* Sadly, the host isn't in our hash table yet. See if + * we have an NSM handle for it. If not, create one. + */ + if (!nsm && !(nsm = nsm_find(sin, hostname, hostname_len))) + goto out; host = kzalloc(sizeof(*host), GFP_KERNEL); - if (!host) - goto nohost; - - addr = sin->sin_addr.s_addr; - sprintf(host->h_name, "%u.%u.%u.%u", NIPQUAD(addr)); - + if (!host) { + nsm_release(nsm); + goto out; + } + host->h_name = nsm->sm_name; host->h_addr = *sin; host->h_addr.sin_port = 0; /* ouch! */ host->h_version = version; @@ -129,6 +147,7 @@ nlm_lookup_host(int server, const struct sockaddr_in *sin, 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 = server; host->h_next = nlm_hosts[hash]; nlm_hosts[hash] = host; @@ -140,7 +159,7 @@ nlm_lookup_host(int server, const struct sockaddr_in *sin, if (++nrhosts > NLM_HOST_MAX) next_gc = 0; -nohost: +out: mutex_unlock(&nlm_host_mutex); return host; } @@ -393,3 +412,83 @@ nlm_gc_hosts(void) next_gc = jiffies + NLM_HOST_COLLECT; } + +/* + * Manage NSM handles + */ +static LIST_HEAD(nsm_handles); +static DECLARE_MUTEX(nsm_sema); + +static struct nsm_handle * +__nsm_find(const struct sockaddr_in *sin, + const char *hostname, int hostname_len, + int create) +{ + struct nsm_handle *nsm = NULL; + struct list_head *pos; + + if (!sin) + return NULL; + + if (hostname && memchr(hostname, '/', hostname_len) != NULL) { + if (printk_ratelimit()) { + printk(KERN_WARNING "Invalid hostname \"%.*s\" " + "in NFS lock request\n", + hostname_len, hostname); + } + return NULL; + } + + down(&nsm_sema); + list_for_each(pos, &nsm_handles) { + nsm = list_entry(pos, struct nsm_handle, sm_link); + + if (!nlm_cmp_addr(&nsm->sm_addr, sin)) + continue; + atomic_inc(&nsm->sm_count); + goto out; + } + + if (!create) { + nsm = NULL; + goto out; + } + + nsm = kzalloc(sizeof(*nsm) + hostname_len + 1, GFP_KERNEL); + if (nsm != NULL) { + nsm->sm_addr = *sin; + nsm->sm_name = (char *) (nsm + 1); + memcpy(nsm->sm_name, hostname, hostname_len); + nsm->sm_name[hostname_len] = '\0'; + atomic_set(&nsm->sm_count, 1); + + list_add(&nsm->sm_link, &nsm_handles); + } + +out: up(&nsm_sema); + return nsm; +} + +struct nsm_handle * +nsm_find(const struct sockaddr_in *sin, const char *hostname, int hostname_len) +{ + return __nsm_find(sin, hostname, hostname_len, 1); +} + +/* + * Release an NSM handle + */ +void +nsm_release(struct nsm_handle *nsm) +{ + if (!nsm) + return; + if (atomic_dec_and_test(&nsm->sm_count)) { + down(&nsm_sema); + if (atomic_read(&nsm->sm_count) == 0) { + list_del(&nsm->sm_link); + kfree(nsm); + } + up(&nsm_sema); + } +} diff --git a/fs/lockd/mon.c b/fs/lockd/mon.c index e02a1a4dfc..e27981403f 100644 --- a/fs/lockd/mon.c +++ b/fs/lockd/mon.c @@ -70,11 +70,14 @@ nsm_mon_unmon(struct nlm_host *host, u32 proc, struct nsm_res *res) int nsm_monitor(struct nlm_host *host) { + struct nsm_handle *nsm = host->h_nsmhandle; struct nsm_res res; int status; dprintk("lockd: nsm_monitor(%s)\n", host->h_name); - if (host->h_monitored) + BUG_ON(nsm == NULL); + + if (nsm->sm_monitored) return 0; status = nsm_mon_unmon(host, SM_MON, &res); @@ -82,7 +85,7 @@ nsm_monitor(struct nlm_host *host) if (status < 0 || res.status != 0) printk(KERN_NOTICE "lockd: cannot monitor %s\n", host->h_name); else - host->h_monitored = 1; + nsm->sm_monitored = 1; return status; } @@ -92,19 +95,22 @@ nsm_monitor(struct nlm_host *host) int nsm_unmonitor(struct nlm_host *host) { + struct nsm_handle *nsm = host->h_nsmhandle; struct nsm_res res; int status = 0; dprintk("lockd: nsm_unmonitor(%s)\n", host->h_name); - if (!host->h_monitored) + if (nsm == NULL) return 0; - host->h_monitored = 0; + host->h_nsmhandle = NULL; if (!host->h_killed) { status = nsm_mon_unmon(host, SM_UNMON, &res); if (status < 0) printk(KERN_NOTICE "lockd: cannot unmonitor %s\n", host->h_name); + nsm->sm_monitored = 0; } + nsm_release(nsm); return status; } diff --git a/include/linux/lockd/lockd.h b/include/linux/lockd/lockd.h index 0f9b236bca..ab2ffc8a0b 100644 --- a/include/linux/lockd/lockd.h +++ b/include/linux/lockd/lockd.h @@ -40,14 +40,13 @@ struct nlm_host { struct nlm_host * h_next; /* linked list (hash table) */ struct sockaddr_in h_addr; /* peer address */ struct rpc_clnt * h_rpcclnt; /* RPC client to talk to peer */ - char h_name[20]; /* remote hostname */ + char * h_name; /* remote hostname */ u32 h_version; /* interface version */ unsigned short h_proto; /* transport proto */ unsigned short h_reclaiming : 1, h_server : 1, /* server side, not client side */ h_inuse : 1, - h_killed : 1, - h_monitored : 1; + h_killed : 1; wait_queue_head_t h_gracewait; /* wait while reclaiming */ struct rw_semaphore h_rwsem; /* Reboot recovery lock */ u32 h_state; /* pseudo-state counter */ @@ -61,6 +60,16 @@ struct nlm_host { spinlock_t h_lock; struct list_head h_granted; /* Locks in GRANTED state */ struct list_head h_reclaim; /* Locks in RECLAIM state */ + struct nsm_handle * h_nsmhandle; /* NSM status handle */ +}; + +struct nsm_handle { + struct list_head sm_link; + atomic_t sm_count; + char * sm_name; + struct sockaddr_in sm_addr; + unsigned int sm_monitored : 1, + sm_sticky : 1; /* don't unmonitor */ }; /* @@ -171,6 +180,8 @@ 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 *); +struct nsm_handle *nsm_find(const struct sockaddr_in *, const char *, int); +void nsm_release(struct nsm_handle *); /*