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>

4 files changed, 11 insertions, 18 deletions

diff --git a/net/core/dev.c b/net/core/dev.c
index 18d8b5acc34..a06a7a58dd1 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -658,11 +658,10 @@ __setup("netdev=", netdev_boot_setup);
 
 struct net_device *__dev_get_by_name(struct net *net, const char *name)
 {
-	struct hlist_node *p;
 	struct net_device *dev;
 	struct hlist_head *head = dev_name_hash(net, name);
 
-	hlist_for_each_entry(dev, p, head, name_hlist)
+	hlist_for_each_entry(dev, head, name_hlist)
 		if (!strncmp(dev->name, name, IFNAMSIZ))
 			return dev;
 
@@ -684,11 +683,10 @@ EXPORT_SYMBOL(__dev_get_by_name);
 
 struct net_device *dev_get_by_name_rcu(struct net *net, const char *name)
 {
-	struct hlist_node *p;
 	struct net_device *dev;
 	struct hlist_head *head = dev_name_hash(net, name);
 
-	hlist_for_each_entry_rcu(dev, p, head, name_hlist)
+	hlist_for_each_entry_rcu(dev, head, name_hlist)
 		if (!strncmp(dev->name, name, IFNAMSIZ))
 			return dev;
 
@@ -735,11 +733,10 @@ EXPORT_SYMBOL(dev_get_by_name);
 
 struct net_device *__dev_get_by_index(struct net *net, int ifindex)
 {
-	struct hlist_node *p;
 	struct net_device *dev;
 	struct hlist_head *head = dev_index_hash(net, ifindex);
 
-	hlist_for_each_entry(dev, p, head, index_hlist)
+	hlist_for_each_entry(dev, head, index_hlist)
 		if (dev->ifindex == ifindex)
 			return dev;
 
@@ -760,11 +757,10 @@ EXPORT_SYMBOL(__dev_get_by_index);
 
 struct net_device *dev_get_by_index_rcu(struct net *net, int ifindex)
 {
-	struct hlist_node *p;
 	struct net_device *dev;
 	struct hlist_head *head = dev_index_hash(net, ifindex);
 
-	hlist_for_each_entry_rcu(dev, p, head, index_hlist)
+	hlist_for_each_entry_rcu(dev, head, index_hlist)
 		if (dev->ifindex == ifindex)
 			return dev;
 
diff --git a/net/core/flow.c b/net/core/flow.c
index 43f7495df27..c56ea6f7f6c 100644
--- a/net/core/flow.c
+++ b/net/core/flow.c
@@ -132,14 +132,14 @@ static void __flow_cache_shrink(struct flow_cache *fc,
 				int shrink_to)
 {
 	struct flow_cache_entry *fle;
-	struct hlist_node *entry, *tmp;
+	struct hlist_node *tmp;
 	LIST_HEAD(gc_list);
 	int i, deleted = 0;
 
 	for (i = 0; i < flow_cache_hash_size(fc); i++) {
 		int saved = 0;
 
-		hlist_for_each_entry_safe(fle, entry, tmp,
+		hlist_for_each_entry_safe(fle, tmp,
 					  &fcp->hash_table[i], u.hlist) {
 			if (saved < shrink_to &&
 			    flow_entry_valid(fle)) {
@@ -211,7 +211,6 @@ flow_cache_lookup(struct net *net, const struct flowi *key, u16 family, u8 dir,
 	struct flow_cache *fc = &flow_cache_global;
 	struct flow_cache_percpu *fcp;
 	struct flow_cache_entry *fle, *tfle;
-	struct hlist_node *entry;
 	struct flow_cache_object *flo;
 	size_t keysize;
 	unsigned int hash;
@@ -235,7 +234,7 @@ flow_cache_lookup(struct net *net, const struct flowi *key, u16 family, u8 dir,
 		flow_new_hash_rnd(fc, fcp);
 
 	hash = flow_hash_code(fc, fcp, key, keysize);
-	hlist_for_each_entry(tfle, entry, &fcp->hash_table[hash], u.hlist) {
+	hlist_for_each_entry(tfle, &fcp->hash_table[hash], u.hlist) {
 		if (tfle->net == net &&
 		    tfle->family == family &&
 		    tfle->dir == dir &&
@@ -301,13 +300,13 @@ static void flow_cache_flush_tasklet(unsigned long data)
 	struct flow_cache *fc = info->cache;
 	struct flow_cache_percpu *fcp;
 	struct flow_cache_entry *fle;
-	struct hlist_node *entry, *tmp;
+	struct hlist_node *tmp;
 	LIST_HEAD(gc_list);
 	int i, deleted = 0;
 
 	fcp = this_cpu_ptr(fc->percpu);
 	for (i = 0; i < flow_cache_hash_size(fc); i++) {
-		hlist_for_each_entry_safe(fle, entry, tmp,
+		hlist_for_each_entry_safe(fle, tmp,
 					  &fcp->hash_table[i], u.hlist) {
 			if (flow_entry_valid(fle))
 				continue;
diff --git a/net/core/net-procfs.c b/net/core/net-procfs.c
index 0f6bb6f8d39..3174f1998ee 100644
--- a/net/core/net-procfs.c
+++ b/net/core/net-procfs.c
@@ -16,12 +16,11 @@ static inline struct net_device *dev_from_same_bucket(struct seq_file *seq, loff
 {
 	struct net *net = seq_file_net(seq);
 	struct net_device *dev;
-	struct hlist_node *p;
 	struct hlist_head *h;
 	unsigned int count = 0, offset = get_offset(*pos);
 
 	h = &net->dev_name_head[get_bucket(*pos)];
-	hlist_for_each_entry_rcu(dev, p, h, name_hlist) {
+	hlist_for_each_entry_rcu(dev, h, name_hlist) {
 		if (++count == offset)
 			return dev;
 	}
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index d8aa20f6a46..b376410ff25 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -1060,7 +1060,6 @@ static int rtnl_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
 	int idx = 0, s_idx;
 	struct net_device *dev;
 	struct hlist_head *head;
-	struct hlist_node *node;
 	struct nlattr *tb[IFLA_MAX+1];
 	u32 ext_filter_mask = 0;
 
@@ -1080,7 +1079,7 @@ static int rtnl_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
 		idx = 0;
 		head = &net->dev_index_head[h];
-		hlist_for_each_entry_rcu(dev, node, head, index_hlist) {
+		hlist_for_each_entry_rcu(dev, head, index_hlist) {
 			if (idx < s_idx)
 				goto cont;
 			if (rtnl_fill_ifinfo(skb, dev, RTM_NEWLINK,