From d22b1cff099737f74f3ac5950094508b4cddec1e Mon Sep 17 00:00:00 2001
From: "J. Bruce Fields" <bfields@citi.umich.edu>
Date: Wed, 6 Feb 2008 15:05:12 -0500
Subject: lockd: reject reclaims outside the grace period

The current lockd does not reject reclaims that arrive outside of the
grace period.

Accepting a reclaim means promising to the client that no conflicting
locks were granted since last it held the lock.  We can meet that
promise if we assume the only lockers are nfs clients, and that they are
sufficiently well-behaved to reclaim only locks that they held before,
and that only reclaim locks have been permitted so far.  Once we leave
the grace period (and start permitting non-reclaims), we can no longer
keep that promise.  So we must start rejecting reclaims at that point.

Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
---
 fs/lockd/svclock.c | 4 ++++
 1 file changed, 4 insertions(+)

(limited to 'fs')

diff --git a/fs/lockd/svclock.c b/fs/lockd/svclock.c
index 808d246ada4d..6063a8e4b9f3 100644
--- a/fs/lockd/svclock.c
+++ b/fs/lockd/svclock.c
@@ -410,6 +410,10 @@ nlmsvc_lock(struct svc_rqst *rqstp, struct nlm_file *file,
 		ret = nlm_lck_denied_grace_period;
 		goto out;
 	}
+	if (reclaim && !locks_in_grace()) {
+		ret = nlm_lck_denied_grace_period;
+		goto out;
+	}
 
 	if (!wait)
 		lock->fl.fl_flags &= ~FL_SLEEP;
-- 
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