Commit 8dead0db authored by Olaf Kirch's avatar Olaf Kirch Committed by Linus Torvalds
Browse files

[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: default avatarOlaf Kirch <okir@suse.de>
Signed-off-by: default avatarNeil Brown <neilb@suse.de>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent db4e4c9a

fs/lockd/clntlock.c

+2 −1
Original line number Diff line number Diff line
@@ -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);

fs/lockd/host.c

+110 −11
Original line number Diff line number Diff line
@@ -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);

	}

}

fs/lockd/mon.c

+10 −4
Original line number Diff line number Diff line
@@ -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;

}

include/linux/lockd/lockd.h

+14 −3
Original line number Diff line number Diff line
@@ -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 *);





/*

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