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>

2 files changed, 4 insertions, 8 deletions

diff --git a/net/rds/bind.c b/net/rds/bind.c
index 637bde56c9db..b5ad65a0067e 100644
--- a/net/rds/bind.c
+++ b/net/rds/bind.c
@@ -52,13 +52,12 @@ static struct rds_sock *rds_bind_lookup(__be32 addr, __be16 port,
                                         struct rds_sock *insert)
 {
         struct rds_sock *rs;
-        struct hlist_node *node;
         struct hlist_head *head = hash_to_bucket(addr, port);
         u64 cmp;
         u64 needle = ((u64)be32_to_cpu(addr) << 32) | be16_to_cpu(port);
 
         rcu_read_lock();
-        hlist_for_each_entry_rcu(rs, node, head, rs_bound_node) {
+        hlist_for_each_entry_rcu(rs, head, rs_bound_node) {
                 cmp = ((u64)be32_to_cpu(rs->rs_bound_addr) << 32) |
                       be16_to_cpu(rs->rs_bound_port);
 
diff --git a/net/rds/connection.c b/net/rds/connection.c
index 9e07c756d1f9..642ad42c416b 100644
--- a/net/rds/connection.c
+++ b/net/rds/connection.c
@@ -69,9 +69,8 @@ static struct rds_connection *rds_conn_lookup(struct hlist_head *head,
                                               struct rds_transport *trans)
 {
         struct rds_connection *conn, *ret = NULL;
-        struct hlist_node *pos;
 
-        hlist_for_each_entry_rcu(conn, pos, head, c_hash_node) {
+        hlist_for_each_entry_rcu(conn, head, c_hash_node) {
                 if (conn->c_faddr == faddr && conn->c_laddr == laddr &&
                                 conn->c_trans == trans) {
                         ret = conn;
@@ -376,7 +375,6 @@ static void rds_conn_message_info(struct socket *sock, unsigned int len,
                                   int want_send)
 {
         struct hlist_head *head;
-        struct hlist_node *pos;
         struct list_head *list;
         struct rds_connection *conn;
         struct rds_message *rm;
@@ -390,7 +388,7 @@ static void rds_conn_message_info(struct socket *sock, unsigned int len,
 
         for (i = 0, head = rds_conn_hash; i < ARRAY_SIZE(rds_conn_hash);
              i++, head++) {
-                hlist_for_each_entry_rcu(conn, pos, head, c_hash_node) {
+                hlist_for_each_entry_rcu(conn, head, c_hash_node) {
                         if (want_send)
                                 list = &conn->c_send_queue;
                         else
@@ -439,7 +437,6 @@ void rds_for_each_conn_info(struct socket *sock, unsigned int len,
 {
         uint64_t buffer[(item_len + 7) / 8];
         struct hlist_head *head;
-        struct hlist_node *pos;
         struct rds_connection *conn;
         size_t i;
 
@@ -450,7 +447,7 @@ void rds_for_each_conn_info(struct socket *sock, unsigned int len,
 
         for (i = 0, head = rds_conn_hash; i < ARRAY_SIZE(rds_conn_hash);
              i++, head++) {
-                hlist_for_each_entry_rcu(conn, pos, head, c_hash_node) {
+                hlist_for_each_entry_rcu(conn, head, c_hash_node) {
 
                         /* XXX no c_lock usage.. */
                         if (!visitor(conn, buffer))