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, 9 deletions

diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
index 87d284289012..51be64f163ec 100644
--- a/net/unix/af_unix.c
+++ b/net/unix/af_unix.c
@@ -263,9 +263,8 @@ static struct sock *__unix_find_socket_byname(struct net *net,
                                               int len, int type, unsigned int hash)
 {
         struct sock *s;
-        struct hlist_node *node;
 
-        sk_for_each(s, node, &unix_socket_table[hash ^ type]) {
+        sk_for_each(s, &unix_socket_table[hash ^ type]) {
                 struct unix_sock *u = unix_sk(s);
 
                 if (!net_eq(sock_net(s), net))
@@ -298,10 +297,9 @@ static inline struct sock *unix_find_socket_byname(struct net *net,
 static struct sock *unix_find_socket_byinode(struct inode *i)
 {
         struct sock *s;
-        struct hlist_node *node;
 
         spin_lock(&unix_table_lock);
-        sk_for_each(s, node,
+        sk_for_each(s,
                     &unix_socket_table[i->i_ino & (UNIX_HASH_SIZE - 1)]) {
                 struct dentry *dentry = unix_sk(s)->path.dentry;
 
diff --git a/net/unix/diag.c b/net/unix/diag.c
index 5ac19dc1d5e4..d591091603bf 100644
--- a/net/unix/diag.c
+++ b/net/unix/diag.c
@@ -192,10 +192,9 @@ static int unix_diag_dump(struct sk_buff *skb, struct netlink_callback *cb)
              slot < ARRAY_SIZE(unix_socket_table);
              s_num = 0, slot++) {
                 struct sock *sk;
-                struct hlist_node *node;
 
                 num = 0;
-                sk_for_each(sk, node, &unix_socket_table[slot]) {
+                sk_for_each(sk, &unix_socket_table[slot]) {
                         if (!net_eq(sock_net(sk), net))
                                 continue;
                         if (num < s_num)
@@ -226,9 +225,7 @@ static struct sock *unix_lookup_by_ino(int ino)
 
         spin_lock(&unix_table_lock);
         for (i = 0; i < ARRAY_SIZE(unix_socket_table); i++) {
-                struct hlist_node *node;
-
-                sk_for_each(sk, node, &unix_socket_table[i])
+                sk_for_each(sk, &unix_socket_table[i])
                         if (ino == sock_i_ino(sk)) {
                                 sock_hold(sk);
                                 spin_unlock(&unix_table_lock);