Commit 24e36663 authored by NeilBrown's avatar NeilBrown Committed by Linus Torvalds
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[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: 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 bc591ccf

fs/lockd/clntlock.c

+1 −1
Original line number Diff line number Diff line
@@ -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. */

fs/lockd/svc.c

+40 −7
Original line number Diff line number Diff line
@@ -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);

fs/nfs/client.c

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

fs/nfsd/nfssvc.c

+10 −6
Original line number Diff line number Diff line
@@ -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 --;

include/linux/lockd/bind.h

+1 −1
Original line number Diff line number Diff line
@@ -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 */

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