Commit 4a3ae42d authored by NeilBrown's avatar NeilBrown Committed by Linus Torvalds
Browse files

[PATCH] knfsd: Correctly handle error condition from lockd_up 



If lockd_up fails - what should we expect?  Do we have to later call
lockd_down?

Well the nfs client thinks "no", the nfs server thinks "yes".  lockd thinks
"yes".

The only answer that really makes sense is "no" !!

So:
  Make lockd_up only increment  nlmsvc_users on success.
  Make nfsd handle errors from lockd_up properly.
  Make sure lockd_up(0) never fails when lockd is running
    so that the 'reclaimer' call to lockd_up doesn't need to
    be error checked.

Cc: "J. Bruce Fields" <bfields@fieldses.org>
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 7dcf91ec

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(0);

	lockd_up(0); /* note: this cannot fail as lockd is already running */



	nlmclnt_prepare_reclaim(host);

	/* First, reclaim all locks that have been marked. */

fs/lockd/svc.c

+5 −7
Original line number Diff line number Diff line
@@ -253,15 +253,11 @@ lockd_up(int proto) /* Maybe add a 'family' option when IPv6 is supported ?? */ 
	int			error = 0;



	mutex_lock(&nlmsvc_mutex);

	/*

	 * Unconditionally increment the user count ... this is

	 * the number of clients who _want_ a lockd process.

	 */

	nlmsvc_users++; 

	/*

	 * Check whether we're already up and running.

	 */

	if (nlmsvc_pid) {

		if (proto)

			error = make_socks(nlmsvc_serv, proto);

		goto out;

	}
@@ -270,7 +266,7 @@ lockd_up(int proto) /* Maybe add a 'family' option when IPv6 is supported ?? */ 
	 * Sanity check: if there's no pid,

	 * we should be the first user ...

	 */

	if (nlmsvc_users > 1)

	if (nlmsvc_users)

		printk(KERN_WARNING

			"lockd_up: no pid, %d users??\n", nlmsvc_users);
@@ -302,6 +298,8 @@ lockd_up(int proto) /* Maybe add a 'family' option when IPv6 is supported ?? */ 
destroy_and_out:

	svc_destroy(serv);

out:

	if (!error)

		nlmsvc_users++;

	mutex_unlock(&nlmsvc_mutex);

	return error;

}

fs/nfsd/nfssvc.c

+10 −6
Original line number Diff line number Diff line
@@ -221,18 +221,22 @@ static int nfsd_init_socks(int port) 
	if (!list_empty(&nfsd_serv->sv_permsocks))

		return 0;



	error = lockd_up(IPPROTO_UDP);

	if (error >= 0) {

		error = svc_makesock(nfsd_serv, IPPROTO_UDP, port);

		if (error < 0)

		return error;

	error = lockd_up(IPPROTO_UDP);

			lockd_down();

	}

	if (error < 0)

		return error;



#ifdef CONFIG_NFSD_TCP

	error = lockd_up(IPPROTO_TCP);

	if (error >= 0) {

		error = svc_makesock(nfsd_serv, IPPROTO_TCP, port);

		if (error < 0)

		return error;

	error = lockd_up(IPPROTO_TCP);

			lockd_down();

	}

	if (error < 0)

		return error;

#endif

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