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>

1 files changed, 12 insertions, 21 deletions

diff --git a/net/ipv4/fib_trie.c b/net/ipv4/fib_trie.c
index 61e03da3e1f5..ff06b7543d9f 100644
--- a/net/ipv4/fib_trie.c
+++ b/net/ipv4/fib_trie.c
@@ -920,10 +920,9 @@ nomem:
 static struct leaf_info *find_leaf_info(struct leaf *l, int plen)
 {
         struct hlist_head *head = &l->list;
-        struct hlist_node *node;
         struct leaf_info *li;
 
-        hlist_for_each_entry_rcu(li, node, head, hlist)
+        hlist_for_each_entry_rcu(li, head, hlist)
                 if (li->plen == plen)
                         return li;
 
@@ -943,12 +942,11 @@ static inline struct list_head *get_fa_head(struct leaf *l, int plen)
 static void insert_leaf_info(struct hlist_head *head, struct leaf_info *new)
 {
         struct leaf_info *li = NULL, *last = NULL;
-        struct hlist_node *node;
 
         if (hlist_empty(head)) {
                 hlist_add_head_rcu(&new->hlist, head);
         } else {
-                hlist_for_each_entry(li, node, head, hlist) {
+                hlist_for_each_entry(li, head, hlist) {
                         if (new->plen > li->plen)
                                 break;
 
@@ -1354,9 +1352,8 @@ static int check_leaf(struct fib_table *tb, struct trie *t, struct leaf *l,
 {
         struct leaf_info *li;
         struct hlist_head *hhead = &l->list;
-        struct hlist_node *node;
 
-        hlist_for_each_entry_rcu(li, node, hhead, hlist) {
+        hlist_for_each_entry_rcu(li, hhead, hlist) {
                 struct fib_alias *fa;
 
                 if (l->key != (key & li->mask_plen))
@@ -1740,10 +1737,10 @@ static int trie_flush_leaf(struct leaf *l)
 {
         int found = 0;
         struct hlist_head *lih = &l->list;
-        struct hlist_node *node, *tmp;
+        struct hlist_node *tmp;
         struct leaf_info *li = NULL;
 
-        hlist_for_each_entry_safe(li, node, tmp, lih, hlist) {
+        hlist_for_each_entry_safe(li, tmp, lih, hlist) {
                 found += trie_flush_list(&li->falh);
 
                 if (list_empty(&li->falh)) {
@@ -1895,14 +1892,13 @@ static int fn_trie_dump_leaf(struct leaf *l, struct fib_table *tb,
                         struct sk_buff *skb, struct netlink_callback *cb)
 {
         struct leaf_info *li;
-        struct hlist_node *node;
         int i, s_i;
 
         s_i = cb->args[4];
         i = 0;
 
         /* rcu_read_lock is hold by caller */
-        hlist_for_each_entry_rcu(li, node, &l->list, hlist) {
+        hlist_for_each_entry_rcu(li, &l->list, hlist) {
                 if (i < s_i) {
                         i++;
                         continue;
@@ -2092,14 +2088,13 @@ static void trie_collect_stats(struct trie *t, struct trie_stat *s)
                 if (IS_LEAF(n)) {
                         struct leaf *l = (struct leaf *)n;
                         struct leaf_info *li;
-                        struct hlist_node *tmp;
 
                         s->leaves++;
                         s->totdepth += iter.depth;
                         if (iter.depth > s->maxdepth)
                                 s->maxdepth = iter.depth;
 
-                        hlist_for_each_entry_rcu(li, tmp, &l->list, hlist)
+                        hlist_for_each_entry_rcu(li, &l->list, hlist)
                                 ++s->prefixes;
                 } else {
                         const struct tnode *tn = (const struct tnode *) n;
@@ -2200,10 +2195,9 @@ static int fib_triestat_seq_show(struct seq_file *seq, void *v)
 
         for (h = 0; h < FIB_TABLE_HASHSZ; h++) {
                 struct hlist_head *head = &net->ipv4.fib_table_hash[h];
-                struct hlist_node *node;
                 struct fib_table *tb;
 
-                hlist_for_each_entry_rcu(tb, node, head, tb_hlist) {
+                hlist_for_each_entry_rcu(tb, head, tb_hlist) {
                         struct trie *t = (struct trie *) tb->tb_data;
                         struct trie_stat stat;
 
@@ -2245,10 +2239,9 @@ static struct rt_trie_node *fib_trie_get_idx(struct seq_file *seq, loff_t pos)
 
         for (h = 0; h < FIB_TABLE_HASHSZ; h++) {
                 struct hlist_head *head = &net->ipv4.fib_table_hash[h];
-                struct hlist_node *node;
                 struct fib_table *tb;
 
-                hlist_for_each_entry_rcu(tb, node, head, tb_hlist) {
+                hlist_for_each_entry_rcu(tb, head, tb_hlist) {
                         struct rt_trie_node *n;
 
                         for (n = fib_trie_get_first(iter,
@@ -2298,7 +2291,7 @@ static void *fib_trie_seq_next(struct seq_file *seq, void *v, loff_t *pos)
         /* new hash chain */
         while (++h < FIB_TABLE_HASHSZ) {
                 struct hlist_head *head = &net->ipv4.fib_table_hash[h];
-                hlist_for_each_entry_rcu(tb, tb_node, head, tb_hlist) {
+                hlist_for_each_entry_rcu(tb, head, tb_hlist) {
                         n = fib_trie_get_first(iter, (struct trie *) tb->tb_data);
                         if (n)
                                 goto found;
@@ -2381,13 +2374,12 @@ static int fib_trie_seq_show(struct seq_file *seq, void *v)
         } else {
                 struct leaf *l = (struct leaf *) n;
                 struct leaf_info *li;
-                struct hlist_node *node;
                 __be32 val = htonl(l->key);
 
                 seq_indent(seq, iter->depth);
                 seq_printf(seq, "  |-- %pI4\n", &val);
 
-                hlist_for_each_entry_rcu(li, node, &l->list, hlist) {
+                hlist_for_each_entry_rcu(li, &l->list, hlist) {
                         struct fib_alias *fa;
 
                         list_for_each_entry_rcu(fa, &li->falh, fa_list) {
@@ -2532,7 +2524,6 @@ static int fib_route_seq_show(struct seq_file *seq, void *v)
 {
         struct leaf *l = v;
         struct leaf_info *li;
-        struct hlist_node *node;
 
         if (v == SEQ_START_TOKEN) {
                 seq_printf(seq, "%-127s\n", "Iface\tDestination\tGateway "
@@ -2541,7 +2532,7 @@ static int fib_route_seq_show(struct seq_file *seq, void *v)
                 return 0;
         }
 
-        hlist_for_each_entry_rcu(li, node, &l->list, hlist) {
+        hlist_for_each_entry_rcu(li, &l->list, hlist) {
                 struct fib_alias *fa;
                 __be32 mask, prefix;