[PATCH 10/11] nfsd: allow delegation state ids to be revoked and then freed

[NeilBrown <neilb@xxxxxxx>]

Revoking state through 'unlock_filesystem' now revokes any delegation
states found.  When the stateids are then freed by the client, the
revoked stateids will be cleaned up correctly.

As there is already support for revoking delegations, we build on that
for admin-revoking.

Signed-off-by: NeilBrown <neilb@xxxxxxx>
---
 fs/nfsd/nfs4state.c | 28 +++++++++++++++++++++++++---
 1 file changed, 25 insertions(+), 3 deletions(-)

diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 8712eb81123f..3d85c88ec4d7 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -1340,9 +1340,12 @@ unhash_delegation_locked(struct nfs4_delegation *dp, unsigned short statusmask)
 	if (!delegation_hashed(dp))
 		return false;
 
-	if (dp->dl_stid.sc_client->cl_minorversion == 0)
+	if (statusmask == NFS4_STID_REVOKED &&
+	    dp->dl_stid.sc_client->cl_minorversion == 0)
 		statusmask = NFS4_STID_CLOSED;
 	dp->dl_stid.sc_status |= statusmask;
+	if (statusmask & NFS4_STID_ADMIN_REVOKED)
+		atomic_inc(&dp->dl_stid.sc_client->cl_admin_revoked);
 
 	/* Ensure that deleg break won't try to requeue it */
 	++dp->dl_time;
@@ -1373,7 +1376,8 @@ static void revoke_delegation(struct nfs4_delegation *dp)
 
 	trace_nfsd_stid_revoke(&dp->dl_stid);
 
-	if (dp->dl_stid.sc_status & NFS4_STID_REVOKED) {
+	if (dp->dl_stid.sc_status &
+	    (NFS4_STID_REVOKED | NFS4_STID_ADMIN_REVOKED)) {
 		spin_lock(&clp->cl_lock);
 		refcount_inc(&dp->dl_stid.sc_count);
 		list_add(&dp->dl_recall_lru, &clp->cl_revoked);
@@ -1708,7 +1712,7 @@ void nfsd4_revoke_states(struct net *net, struct super_block *sb)
 	unsigned int idhashval;
 	unsigned int sc_types;
 
-	sc_types = NFS4_OPEN_STID | NFS4_LOCK_STID;
+	sc_types = NFS4_OPEN_STID | NFS4_LOCK_STID | NFS4_DELEG_STID;
 
 	spin_lock(&nn->client_lock);
 	for (idhashval = 0; idhashval < CLIENT_HASH_MASK; idhashval++) {
@@ -1720,6 +1724,7 @@ void nfsd4_revoke_states(struct net *net, struct super_block *sb)
 								  sc_types);
 			if (stid) {
 				struct nfs4_ol_stateid *stp;
+				struct nfs4_delegation *dp;
 
 				spin_unlock(&nn->client_lock);
 				switch (stid->sc_type) {
@@ -1765,6 +1770,16 @@ void nfsd4_revoke_states(struct net *net, struct super_block *sb)
 						spin_unlock(&clp->cl_lock);
 					mutex_unlock(&stp->st_mutex);
 					break;
+				case NFS4_DELEG_STID:
+					dp = delegstateid(stid);
+					spin_lock(&state_lock);
+					if (!unhash_delegation_locked(
+						    dp, NFS4_STID_ADMIN_REVOKED))
+						dp = NULL;
+					spin_unlock(&state_lock);
+					if (dp)
+						revoke_delegation(dp);
+					break;
 				}
 				nfs4_put_stid(stid);
 				spin_lock(&nn->client_lock);
@@ -4705,6 +4720,7 @@ static void nfsd_drop_revoked_stid(struct nfs4_stid *s)
 	struct nfs4_client *cl = s->sc_client;
 	LIST_HEAD(reaplist);
 	struct nfs4_ol_stateid *stp;
+	struct nfs4_delegation *dp;
 	bool unhashed;
 
 	switch (s->sc_type) {
@@ -4722,6 +4738,12 @@ static void nfsd_drop_revoked_stid(struct nfs4_stid *s)
 		if (unhashed)
 			nfs4_put_stid(s);
 		break;
+	case NFS4_DELEG_STID:
+		dp = delegstateid(s);
+		list_del_init(&dp->dl_recall_lru);
+		spin_unlock(&cl->cl_lock);
+		nfs4_put_stid(s);
+		break;
 	default:
 		spin_unlock(&cl->cl_lock);
 	}
-- 
2.42.1