[PATCH] nfsd4: fix sleep under spinlock

We shouldn't be calling release_deleg under a spinlock.
Signed-off-by: Andy Adamson <andros@citi.umich.edu>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

fs/nfsd/nfs4state.c

@@ -207,7 +207,9 @@ release_delegation(struct nfs4_delegation *dp)
 {
 	list_del_init(&dp->dl_del_perfile);
 	list_del_init(&dp->dl_del_perclnt);
+	spin_lock(&recall_lock);
 	list_del_init(&dp->dl_recall_lru);
+	spin_unlock(&recall_lock);
 	nfs4_close_delegation(dp);
 	nfs4_put_delegation(dp);
 }
@@ -321,6 +323,7 @@ expire_client(struct nfs4_client *clp)
 	struct nfs4_delegation *dp;
 	struct nfs4_callback *cb = &clp->cl_callback;
 	struct rpc_clnt *clnt = clp->cl_callback.cb_client;
+	struct list_head reaplist;
 
 	dprintk("NFSD: expire_client cl_count %d\n",
 	                    atomic_read(&clp->cl_count));
@@ -330,6 +333,8 @@ expire_client(struct nfs4_client *clp)
 		rpc_shutdown_client(clnt);
 		clnt = clp->cl_callback.cb_client = NULL;
 	}
+
+	INIT_LIST_HEAD(&reaplist);
 	spin_lock(&recall_lock);
 	while (!list_empty(&clp->cl_del_perclnt)) {
 		dp = list_entry(clp->cl_del_perclnt.next, struct nfs4_delegation, dl_del_perclnt);
@@ -338,9 +343,15 @@ expire_client(struct nfs4_client *clp)
 
 		/* force release of delegation. */
 		atomic_set(&dp->dl_state, NFS4_RECALL_COMPLETE);
-		release_delegation(dp);
+		list_del_init(&dp->dl_del_perclnt);
+		list_move(&dp->dl_recall_lru, &reaplist);
 	}
 	spin_unlock(&recall_lock);
+	while (!list_empty(&reaplist)) {
+		dp = list_entry(reaplist.next, struct nfs4_delegation, dl_recall_lru);
+		list_del_init(&dp->dl_recall_lru);
+		release_delegation(dp);
+	}
 	list_del(&clp->cl_idhash);
 	list_del(&clp->cl_strhash);
 	list_del(&clp->cl_lru);
@@ -1812,7 +1823,7 @@ nfs4_laundromat(void)
 	struct nfs4_client *clp;
 	struct nfs4_stateowner *sop;
 	struct nfs4_delegation *dp;
-	struct list_head *pos, *next;
+	struct list_head *pos, *next, reaplist;
 	time_t cutoff = get_seconds() - NFSD_LEASE_TIME;
 	time_t t, clientid_val = NFSD_LEASE_TIME;
 	time_t u, test_val = NFSD_LEASE_TIME;
@@ -1832,6 +1843,7 @@ nfs4_laundromat(void)
 			clp->cl_clientid.cl_id);
 		expire_client(clp);
 	}
+	INIT_LIST_HEAD(&reaplist);
 	spin_lock(&recall_lock);
 	list_for_each_safe(pos, next, &del_recall_lru) {
 		dp = list_entry (pos, struct nfs4_delegation, dl_recall_lru);
@@ -1843,9 +1855,14 @@ nfs4_laundromat(void)
 		}
 		dprintk("NFSD: purging unused delegation dp %p, fp %p\n",
 			            dp, dp->dl_flock);
-		release_delegation(dp);
+		list_move(&dp->dl_recall_lru, &reaplist);
 	}
 	spin_unlock(&recall_lock);
+	list_for_each_safe(pos, next, &reaplist) {
+		dp = list_entry (pos, struct nfs4_delegation, dl_recall_lru);
+		list_del_init(&dp->dl_recall_lru);
+		release_delegation(dp);
+	}
 	test_val = NFSD_LEASE_TIME;
 	list_for_each_safe(pos, next, &close_lru) {
 		sop = list_entry(pos, struct nfs4_stateowner, so_close_lru);
@@ -2049,9 +2066,7 @@ nfs4_preprocess_stateid_op(struct svc_fh *current_fh, stateid_t *stateid, int fl
 		renew_client(dp->dl_client);
 		if (flags & DELEG_RET) {
 			atomic_set(&dp->dl_state,NFS4_RECALL_COMPLETE);
-			spin_lock(&recall_lock);
 			release_delegation(dp);
-			spin_unlock(&recall_lock);
 		}
 	}
 	status = nfs_ok;
@@ -3197,7 +3212,7 @@ __nfs4_state_shutdown(void)
 	struct nfs4_client *clp = NULL;
 	struct nfs4_delegation *dp = NULL;
 	struct nfs4_stateowner *sop = NULL;
-	struct list_head *pos, *next;
+	struct list_head *pos, *next, reaplist;
 
 	list_for_each_safe(pos, next, &close_lru) {
 		sop = list_entry(pos, struct nfs4_stateowner, so_close_lru);
@@ -3215,13 +3230,19 @@ __nfs4_state_shutdown(void)
 			expire_client(clp);
 		}
 	}
+	INIT_LIST_HEAD(&reaplist);
 	spin_lock(&recall_lock);
 	list_for_each_safe(pos, next, &del_recall_lru) {
 		dp = list_entry (pos, struct nfs4_delegation, dl_recall_lru);
 		atomic_set(&dp->dl_state, NFS4_RECALL_COMPLETE);
-		release_delegation(dp);
+		list_move(&dp->dl_recall_lru, &reaplist);
 	}
 	spin_unlock(&recall_lock);
+	list_for_each_safe(pos, next, &reaplist) {
+		dp = list_entry (pos, struct nfs4_delegation, dl_recall_lru);
+		list_del_init(&dp->dl_recall_lru);
+		release_delegation(dp);
+	}
 
 	release_all_files();
 	cancel_delayed_work(&laundromat_work);