hlist: drop the node parameter from iterators

I'm not sure why, but the hlist for each entry iterators were conceived

        list_for_each_entry(pos, head, member)

The hlist ones were greedy and wanted an extra parameter:

        hlist_for_each_entry(tpos, pos, head, member)

Why did they need an extra pos parameter? I'm not quite sure. Not only
they don't really need it, it also prevents the iterator from looking
exactly like the list iterator, which is unfortunate.

Besides the semantic patch, there was some manual work required:

 - Fix up the actual hlist iterators in linux/list.h
 - Fix up the declaration of other iterators based on the hlist ones.
 - A very small amount of places were using the 'node' parameter, this
 was modified to use 'obj->member' instead.
 - Coccinelle didn't handle the hlist_for_each_entry_safe iterator
 properly, so those had to be fixed up manually.

The semantic patch which is mostly the work of Peter Senna Tschudin is here:

@@
iterator name hlist_for_each_entry, hlist_for_each_entry_continue, hlist_for_each_entry_from, hlist_for_each_entry_rcu, hlist_for_each_entry_rcu_bh, hlist_for_each_entry_continue_rcu_bh, for_each_busy_worker, ax25_uid_for_each, ax25_for_each, inet_bind_bucket_for_each, sctp_for_each_hentry, sk_for_each, sk_for_each_rcu, sk_for_each_from, sk_for_each_safe, sk_for_each_bound, hlist_for_each_entry_safe, hlist_for_each_entry_continue_rcu, nr_neigh_for_each, nr_neigh_for_each_safe, nr_node_for_each, nr_node_for_each_safe, for_each_gfn_indirect_valid_sp, for_each_gfn_sp, for_each_host;

type T;
expression a,c,d,e;
identifier b;
statement S;
@@

-T b;
    <+... when != b
(
hlist_for_each_entry(a,
- b,
c, d) S
|
hlist_for_each_entry_continue(a,
- b,
c) S
|
hlist_for_each_entry_from(a,
- b,
c) S
|
hlist_for_each_entry_rcu(a,
- b,
c, d) S
|
hlist_for_each_entry_rcu_bh(a,
- b,
c, d) S
|
hlist_for_each_entry_continue_rcu_bh(a,
- b,
c) S
|
for_each_busy_worker(a, c,
- b,
d) S
|
ax25_uid_for_each(a,
- b,
c) S
|
ax25_for_each(a,
- b,
c) S
|
inet_bind_bucket_for_each(a,
- b,
c) S
|
sctp_for_each_hentry(a,
- b,
c) S
|
sk_for_each(a,
- b,
c) S
|
sk_for_each_rcu(a,
- b,
c) S
|
sk_for_each_from
-(a, b)
+(a)
S
+ sk_for_each_from(a) S
|
sk_for_each_safe(a,
- b,
c, d) S
|
sk_for_each_bound(a,
- b,
c) S
|
hlist_for_each_entry_safe(a,
- b,
c, d, e) S
|
hlist_for_each_entry_continue_rcu(a,
- b,
c) S
|
nr_neigh_for_each(a,
- b,
c) S
|
nr_neigh_for_each_safe(a,
- b,
c, d) S
|
nr_node_for_each(a,
- b,
c) S
|
nr_node_for_each_safe(a,
- b,
c, d) S
|
- for_each_gfn_sp(a, c, d, b) S
+ for_each_gfn_sp(a, c, d) S
|
- for_each_gfn_indirect_valid_sp(a, c, d, b) S
+ for_each_gfn_indirect_valid_sp(a, c, d) S
|
for_each_host(a,
- b,
c) S
|
for_each_host_safe(a,
- b,
c, d) S
|
for_each_mesh_entry(a,
- b,
c, d) S
)
    ...+>

[akpm@linux-foundation.org: drop bogus change from net/ipv4/raw.c]
[akpm@linux-foundation.org: drop bogus hunk from net/ipv6/raw.c]
[akpm@linux-foundation.org: checkpatch fixes]
[akpm@linux-foundation.org: fix warnings]
[akpm@linux-foudnation.org: redo intrusive kvm changes]
Tested-by: Peter Senna Tschudin <peter.senna@gmail.com>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

3 files changed, 10 insertions, 16 deletions

diff --git a/net/openvswitch/datapath.c b/net/openvswitch/datapath.c
index 9dc537d..e87a265 100644
--- a/net/openvswitch/datapath.c
+++ b/net/openvswitch/datapath.c
@@ -158,11 +158,10 @@ static struct hlist_head *vport_hash_bucket(const struct datapath *dp,
 struct vport *ovs_lookup_vport(const struct datapath *dp, u16 port_no)
 {
 	struct vport *vport;
-	struct hlist_node *n;
 	struct hlist_head *head;
 
 	head = vport_hash_bucket(dp, port_no);
-	hlist_for_each_entry_rcu(vport, n, head, dp_hash_node) {
+	hlist_for_each_entry_rcu(vport, head, dp_hash_node) {
 		if (vport->port_no == port_no)
 			return vport;
 	}
@@ -1386,9 +1385,9 @@ static void __dp_destroy(struct datapath *dp)
 
 	for (i = 0; i < DP_VPORT_HASH_BUCKETS; i++) {
 		struct vport *vport;
-		struct hlist_node *node, *n;
+		struct hlist_node *n;
 
-		hlist_for_each_entry_safe(vport, node, n, &dp->ports[i], dp_hash_node)
+		hlist_for_each_entry_safe(vport, n, &dp->ports[i], dp_hash_node)
 			if (vport->port_no != OVSP_LOCAL)
 				ovs_dp_detach_port(vport);
 	}
@@ -1825,10 +1824,9 @@ static int ovs_vport_cmd_dump(struct sk_buff *skb, struct netlink_callback *cb)
 	rcu_read_lock();
 	for (i = bucket; i < DP_VPORT_HASH_BUCKETS; i++) {
 		struct vport *vport;
-		struct hlist_node *n;
 
 		j = 0;
-		hlist_for_each_entry_rcu(vport, n, &dp->ports[i], dp_hash_node) {
+		hlist_for_each_entry_rcu(vport, &dp->ports[i], dp_hash_node) {
 			if (j >= skip &&
 			    ovs_vport_cmd_fill_info(vport, skb,
 						    NETLINK_CB(cb->skb).portid,
diff --git a/net/openvswitch/flow.c b/net/openvswitch/flow.c
index c3294ce..20605ec 100644
--- a/net/openvswitch/flow.c
+++ b/net/openvswitch/flow.c
@@ -299,10 +299,10 @@ void ovs_flow_tbl_destroy(struct flow_table *table)
 	for (i = 0; i < table->n_buckets; i++) {
 		struct sw_flow *flow;
 		struct hlist_head *head = flex_array_get(table->buckets, i);
-		struct hlist_node *node, *n;
+		struct hlist_node *n;
 		int ver = table->node_ver;
 
-		hlist_for_each_entry_safe(flow, node, n, head, hash_node[ver]) {
+		hlist_for_each_entry_safe(flow, n, head, hash_node[ver]) {
 			hlist_del_rcu(&flow->hash_node[ver]);
 			ovs_flow_free(flow);
 		}
@@ -332,7 +332,6 @@ struct sw_flow *ovs_flow_tbl_next(struct flow_table *table, u32 *bucket, u32 *la
 {
 	struct sw_flow *flow;
 	struct hlist_head *head;
-	struct hlist_node *n;
 	int ver;
 	int i;
 
@@ -340,7 +339,7 @@ struct sw_flow *ovs_flow_tbl_next(struct flow_table *table, u32 *bucket, u32 *la
 	while (*bucket < table->n_buckets) {
 		i = 0;
 		head = flex_array_get(table->buckets, *bucket);
-		hlist_for_each_entry_rcu(flow, n, head, hash_node[ver]) {
+		hlist_for_each_entry_rcu(flow, head, hash_node[ver]) {
 			if (i < *last) {
 				i++;
 				continue;
@@ -367,11 +366,10 @@ static void flow_table_copy_flows(struct flow_table *old, struct flow_table *new
 	for (i = 0; i < old->n_buckets; i++) {
 		struct sw_flow *flow;
 		struct hlist_head *head;
-		struct hlist_node *n;
 
 		head = flex_array_get(old->buckets, i);
 
-		hlist_for_each_entry(flow, n, head, hash_node[old_ver])
+		hlist_for_each_entry(flow, head, hash_node[old_ver])
 			ovs_flow_tbl_insert(new, flow);
 	}
 	old->keep_flows = true;
@@ -766,14 +764,13 @@ struct sw_flow *ovs_flow_tbl_lookup(struct flow_table *table,
 				struct sw_flow_key *key, int key_len)
 {
 	struct sw_flow *flow;
-	struct hlist_node *n;
 	struct hlist_head *head;
 	u32 hash;
 
 	hash = ovs_flow_hash(key, key_len);
 
 	head = find_bucket(table, hash);
-	hlist_for_each_entry_rcu(flow, n, head, hash_node[table->node_ver]) {
+	hlist_for_each_entry_rcu(flow, head, hash_node[table->node_ver]) {
 
 		if (flow->hash == hash &&
 		    !memcmp(&flow->key, key, key_len)) {
diff --git a/net/openvswitch/vport.c b/net/openvswitch/vport.c
index 70af0be..ba717cc 100644
--- a/net/openvswitch/vport.c
+++ b/net/openvswitch/vport.c
@@ -86,9 +86,8 @@ struct vport *ovs_vport_locate(struct net *net, const char *name)
 {
 	struct hlist_head *bucket = hash_bucket(net, name);
 	struct vport *vport;
-	struct hlist_node *node;
 
-	hlist_for_each_entry_rcu(vport, node, bucket, hash_node)
+	hlist_for_each_entry_rcu(vport, bucket, hash_node)
 		if (!strcmp(name, vport->ops->get_name(vport)) &&
 		    net_eq(ovs_dp_get_net(vport->dp), net))
 			return vport;