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>

6 files changed, 30 insertions, 50 deletions

diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index 4dc0d44a5d31..f2c7e615f902 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -1419,11 +1419,10 @@ int ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
 		  struct net_device *dev, int strict)
 {
 	struct inet6_ifaddr *ifp;
-	struct hlist_node *node;
 	unsigned int hash = inet6_addr_hash(addr);
 
 	rcu_read_lock_bh();
-	hlist_for_each_entry_rcu(ifp, node, &inet6_addr_lst[hash], addr_lst) {
+	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
 		if (!net_eq(dev_net(ifp->idev->dev), net))
 			continue;
 		if (ipv6_addr_equal(&ifp->addr, addr) &&
@@ -1445,9 +1444,8 @@ static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
 {
 	unsigned int hash = inet6_addr_hash(addr);
 	struct inet6_ifaddr *ifp;
-	struct hlist_node *node;
 
-	hlist_for_each_entry(ifp, node, &inet6_addr_lst[hash], addr_lst) {
+	hlist_for_each_entry(ifp, &inet6_addr_lst[hash], addr_lst) {
 		if (!net_eq(dev_net(ifp->idev->dev), net))
 			continue;
 		if (ipv6_addr_equal(&ifp->addr, addr)) {
@@ -1487,10 +1485,9 @@ struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net, const struct in6_addr *add
 {
 	struct inet6_ifaddr *ifp, *result = NULL;
 	unsigned int hash = inet6_addr_hash(addr);
-	struct hlist_node *node;
 
 	rcu_read_lock_bh();
-	hlist_for_each_entry_rcu_bh(ifp, node, &inet6_addr_lst[hash], addr_lst) {
+	hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[hash], addr_lst) {
 		if (!net_eq(dev_net(ifp->idev->dev), net))
 			continue;
 		if (ipv6_addr_equal(&ifp->addr, addr)) {
@@ -2907,11 +2904,10 @@ static int addrconf_ifdown(struct net_device *dev, int how)
 	/* Step 2: clear hash table */
 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
 		struct hlist_head *h = &inet6_addr_lst[i];
-		struct hlist_node *n;
 
 		spin_lock_bh(&addrconf_hash_lock);
 	restart:
-		hlist_for_each_entry_rcu(ifa, n, h, addr_lst) {
+		hlist_for_each_entry_rcu(ifa, h, addr_lst) {
 			if (ifa->idev == idev) {
 				hlist_del_init_rcu(&ifa->addr_lst);
 				addrconf_del_timer(ifa);
@@ -3218,8 +3214,7 @@ static struct inet6_ifaddr *if6_get_first(struct seq_file *seq, loff_t pos)
 	}
 
 	for (; state->bucket < IN6_ADDR_HSIZE; ++state->bucket) {
-		struct hlist_node *n;
-		hlist_for_each_entry_rcu_bh(ifa, n, &inet6_addr_lst[state->bucket],
+		hlist_for_each_entry_rcu_bh(ifa, &inet6_addr_lst[state->bucket],
 					 addr_lst) {
 			if (!net_eq(dev_net(ifa->idev->dev), net))
 				continue;
@@ -3244,9 +3239,8 @@ static struct inet6_ifaddr *if6_get_next(struct seq_file *seq,
 {
 	struct if6_iter_state *state = seq->private;
 	struct net *net = seq_file_net(seq);
-	struct hlist_node *n = &ifa->addr_lst;
 
-	hlist_for_each_entry_continue_rcu_bh(ifa, n, addr_lst) {
+	hlist_for_each_entry_continue_rcu_bh(ifa, addr_lst) {
 		if (!net_eq(dev_net(ifa->idev->dev), net))
 			continue;
 		state->offset++;
@@ -3255,7 +3249,7 @@ static struct inet6_ifaddr *if6_get_next(struct seq_file *seq,
 
 	while (++state->bucket < IN6_ADDR_HSIZE) {
 		state->offset = 0;
-		hlist_for_each_entry_rcu_bh(ifa, n,
+		hlist_for_each_entry_rcu_bh(ifa,
 				     &inet6_addr_lst[state->bucket], addr_lst) {
 			if (!net_eq(dev_net(ifa->idev->dev), net))
 				continue;
@@ -3357,11 +3351,10 @@ int ipv6_chk_home_addr(struct net *net, const struct in6_addr *addr)
 {
 	int ret = 0;
 	struct inet6_ifaddr *ifp = NULL;
-	struct hlist_node *n;
 	unsigned int hash = inet6_addr_hash(addr);
 
 	rcu_read_lock_bh();
-	hlist_for_each_entry_rcu_bh(ifp, n, &inet6_addr_lst[hash], addr_lst) {
+	hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[hash], addr_lst) {
 		if (!net_eq(dev_net(ifp->idev->dev), net))
 			continue;
 		if (ipv6_addr_equal(&ifp->addr, addr) &&
@@ -3383,7 +3376,6 @@ static void addrconf_verify(unsigned long foo)
 {
 	unsigned long now, next, next_sec, next_sched;
 	struct inet6_ifaddr *ifp;
-	struct hlist_node *node;
 	int i;
 
 	rcu_read_lock_bh();
@@ -3395,7 +3387,7 @@ static void addrconf_verify(unsigned long foo)
 
 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
 restart:
-		hlist_for_each_entry_rcu_bh(ifp, node,
+		hlist_for_each_entry_rcu_bh(ifp,
 					 &inet6_addr_lst[i], addr_lst) {
 			unsigned long age;
 
@@ -3866,7 +3858,6 @@ static int inet6_dump_addr(struct sk_buff *skb, struct netlink_callback *cb,
 	struct net_device *dev;
 	struct inet6_dev *idev;
 	struct hlist_head *head;
-	struct hlist_node *node;
 
 	s_h = cb->args[0];
 	s_idx = idx = cb->args[1];
@@ -3876,7 +3867,7 @@ static int inet6_dump_addr(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 (h > s_h || idx > s_idx)
@@ -4222,7 +4213,6 @@ static int inet6_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
 	struct net_device *dev;
 	struct inet6_dev *idev;
 	struct hlist_head *head;
-	struct hlist_node *node;
 
 	s_h = cb->args[0];
 	s_idx = cb->args[1];
@@ -4231,7 +4221,7 @@ static int inet6_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;
 			idev = __in6_dev_get(dev);
diff --git a/net/ipv6/addrlabel.c b/net/ipv6/addrlabel.c
index ff76eecfd622..aad64352cb60 100644
--- a/net/ipv6/addrlabel.c
+++ b/net/ipv6/addrlabel.c
@@ -173,9 +173,8 @@ static struct ip6addrlbl_entry *__ipv6_addr_label(struct net *net,
 						  const struct in6_addr *addr,
 						  int type, int ifindex)
 {
-	struct hlist_node *pos;
 	struct ip6addrlbl_entry *p;
-	hlist_for_each_entry_rcu(p, pos, &ip6addrlbl_table.head, list) {
+	hlist_for_each_entry_rcu(p, &ip6addrlbl_table.head, list) {
 		if (__ip6addrlbl_match(net, p, addr, type, ifindex))
 			return p;
 	}
@@ -261,9 +260,9 @@ static int __ip6addrlbl_add(struct ip6addrlbl_entry *newp, int replace)
 	if (hlist_empty(&ip6addrlbl_table.head)) {
 		hlist_add_head_rcu(&newp->list, &ip6addrlbl_table.head);
 	} else {
-		struct hlist_node *pos, *n;
+		struct hlist_node *n;
 		struct ip6addrlbl_entry *p = NULL;
-		hlist_for_each_entry_safe(p, pos, n,
+		hlist_for_each_entry_safe(p, n,
 					  &ip6addrlbl_table.head, list) {
 			if (p->prefixlen == newp->prefixlen &&
 			    net_eq(ip6addrlbl_net(p), ip6addrlbl_net(newp)) &&
@@ -319,13 +318,13 @@ static int __ip6addrlbl_del(struct net *net,
 			    int ifindex)
 {
 	struct ip6addrlbl_entry *p = NULL;
-	struct hlist_node *pos, *n;
+	struct hlist_node *n;
 	int ret = -ESRCH;
 
 	ADDRLABEL(KERN_DEBUG "%s(prefix=%pI6, prefixlen=%d, ifindex=%d)\n",
 		  __func__, prefix, prefixlen, ifindex);
 
-	hlist_for_each_entry_safe(p, pos, n, &ip6addrlbl_table.head, list) {
+	hlist_for_each_entry_safe(p, n, &ip6addrlbl_table.head, list) {
 		if (p->prefixlen == prefixlen &&
 		    net_eq(ip6addrlbl_net(p), net) &&
 		    p->ifindex == ifindex &&
@@ -380,11 +379,11 @@ static int __net_init ip6addrlbl_net_init(struct net *net)
 static void __net_exit ip6addrlbl_net_exit(struct net *net)
 {
 	struct ip6addrlbl_entry *p = NULL;
-	struct hlist_node *pos, *n;
+	struct hlist_node *n;
 
 	/* Remove all labels belonging to the exiting net */
 	spin_lock(&ip6addrlbl_table.lock);
-	hlist_for_each_entry_safe(p, pos, n, &ip6addrlbl_table.head, list) {
+	hlist_for_each_entry_safe(p, n, &ip6addrlbl_table.head, list) {
 		if (net_eq(ip6addrlbl_net(p), net)) {
 			hlist_del_rcu(&p->list);
 			ip6addrlbl_put(p);
@@ -505,12 +504,11 @@ static int ip6addrlbl_dump(struct sk_buff *skb, struct netlink_callback *cb)
 {
 	struct net *net = sock_net(skb->sk);
 	struct ip6addrlbl_entry *p;
-	struct hlist_node *pos;
 	int idx = 0, s_idx = cb->args[0];
 	int err;
 
 	rcu_read_lock();
-	hlist_for_each_entry_rcu(p, pos, &ip6addrlbl_table.head, list) {
+	hlist_for_each_entry_rcu(p, &ip6addrlbl_table.head, list) {
 		if (idx >= s_idx &&
 		    net_eq(ip6addrlbl_net(p), net)) {
 			if ((err = ip6addrlbl_fill(skb, p,
diff --git a/net/ipv6/inet6_connection_sock.c b/net/ipv6/inet6_connection_sock.c
index b386a2ce4c6f..9bfab19ff3c0 100644
--- a/net/ipv6/inet6_connection_sock.c
+++ b/net/ipv6/inet6_connection_sock.c
@@ -31,7 +31,6 @@ int inet6_csk_bind_conflict(const struct sock *sk,
 			    const struct inet_bind_bucket *tb, bool relax)
 {
 	const struct sock *sk2;
-	const struct hlist_node *node;
 	int reuse = sk->sk_reuse;
 	int reuseport = sk->sk_reuseport;
 	kuid_t uid = sock_i_uid((struct sock *)sk);
@@ -41,7 +40,7 @@ int inet6_csk_bind_conflict(const struct sock *sk,
 	 * See comment in inet_csk_bind_conflict about sock lookup
 	 * vs net namespaces issues.
 	 */
-	sk_for_each_bound(sk2, node, &tb->owners) {
+	sk_for_each_bound(sk2, &tb->owners) {
 		if (sk != sk2 &&
 		    (!sk->sk_bound_dev_if ||
 		     !sk2->sk_bound_dev_if ||
@@ -58,7 +57,7 @@ int inet6_csk_bind_conflict(const struct sock *sk,
 		}
 	}
 
-	return node != NULL;
+	return sk2 != NULL;
 }
 
 EXPORT_SYMBOL_GPL(inet6_csk_bind_conflict);
diff --git a/net/ipv6/ip6_fib.c b/net/ipv6/ip6_fib.c
index 710cafd2e1a9..192dd1a0e188 100644
--- a/net/ipv6/ip6_fib.c
+++ b/net/ipv6/ip6_fib.c
@@ -224,7 +224,6 @@ struct fib6_table *fib6_get_table(struct net *net, u32 id)
 {
 	struct fib6_table *tb;
 	struct hlist_head *head;
-	struct hlist_node *node;
 	unsigned int h;
 
 	if (id == 0)
@@ -232,7 +231,7 @@ struct fib6_table *fib6_get_table(struct net *net, u32 id)
 	h = id & (FIB6_TABLE_HASHSZ - 1);
 	rcu_read_lock();
 	head = &net->ipv6.fib_table_hash[h];
-	hlist_for_each_entry_rcu(tb, node, head, tb6_hlist) {
+	hlist_for_each_entry_rcu(tb, head, tb6_hlist) {
 		if (tb->tb6_id == id) {
 			rcu_read_unlock();
 			return tb;
@@ -363,7 +362,6 @@ static int inet6_dump_fib(struct sk_buff *skb, struct netlink_callback *cb)
 	struct rt6_rtnl_dump_arg arg;
 	struct fib6_walker_t *w;
 	struct fib6_table *tb;
-	struct hlist_node *node;
 	struct hlist_head *head;
 	int res = 0;
 
@@ -398,7 +396,7 @@ static int inet6_dump_fib(struct sk_buff *skb, struct netlink_callback *cb)
 	for (h = s_h; h < FIB6_TABLE_HASHSZ; h++, s_e = 0) {
 		e = 0;
 		head = &net->ipv6.fib_table_hash[h];
-		hlist_for_each_entry_rcu(tb, node, head, tb6_hlist) {
+		hlist_for_each_entry_rcu(tb, head, tb6_hlist) {
 			if (e < s_e)
 				goto next;
 			res = fib6_dump_table(tb, skb, cb);
@@ -1520,14 +1518,13 @@ void fib6_clean_all_ro(struct net *net, int (*func)(struct rt6_info *, void *arg
 		    int prune, void *arg)
 {
 	struct fib6_table *table;
-	struct hlist_node *node;
 	struct hlist_head *head;
 	unsigned int h;
 
 	rcu_read_lock();
 	for (h = 0; h < FIB6_TABLE_HASHSZ; h++) {
 		head = &net->ipv6.fib_table_hash[h];
-		hlist_for_each_entry_rcu(table, node, head, tb6_hlist) {
+		hlist_for_each_entry_rcu(table, head, tb6_hlist) {
 			read_lock_bh(&table->tb6_lock);
 			fib6_clean_tree(net, &table->tb6_root,
 					func, prune, arg);
@@ -1540,14 +1537,13 @@ void fib6_clean_all(struct net *net, int (*func)(struct rt6_info *, void *arg),
 		    int prune, void *arg)
 {
 	struct fib6_table *table;
-	struct hlist_node *node;
 	struct hlist_head *head;
 	unsigned int h;
 
 	rcu_read_lock();
 	for (h = 0; h < FIB6_TABLE_HASHSZ; h++) {
 		head = &net->ipv6.fib_table_hash[h];
-		hlist_for_each_entry_rcu(table, node, head, tb6_hlist) {
+		hlist_for_each_entry_rcu(table, head, tb6_hlist) {
 			write_lock_bh(&table->tb6_lock);
 			fib6_clean_tree(net, &table->tb6_root,
 					func, prune, arg);
diff --git a/net/ipv6/raw.c b/net/ipv6/raw.c
index c65907db8c44..330b5e7b7df6 100644
--- a/net/ipv6/raw.c
+++ b/net/ipv6/raw.c
@@ -71,10 +71,9 @@ static struct sock *__raw_v6_lookup(struct net *net, struct sock *sk,
 		unsigned short num, const struct in6_addr *loc_addr,
 		const struct in6_addr *rmt_addr, int dif)
 {
-	struct hlist_node *node;
 	bool is_multicast = ipv6_addr_is_multicast(loc_addr);
 
-	sk_for_each_from(sk, node)
+	sk_for_each_from(sk)
 		if (inet_sk(sk)->inet_num == num) {
 			struct ipv6_pinfo *np = inet6_sk(sk);
 
diff --git a/net/ipv6/xfrm6_tunnel.c b/net/ipv6/xfrm6_tunnel.c
index 6cc48012b730..de2bcfaaf759 100644
--- a/net/ipv6/xfrm6_tunnel.c
+++ b/net/ipv6/xfrm6_tunnel.c
@@ -89,9 +89,8 @@ static struct xfrm6_tunnel_spi *__xfrm6_tunnel_spi_lookup(struct net *net, const
 {
 	struct xfrm6_tunnel_net *xfrm6_tn = xfrm6_tunnel_pernet(net);
 	struct xfrm6_tunnel_spi *x6spi;
-	struct hlist_node *pos;
 
-	hlist_for_each_entry_rcu(x6spi, pos,
+	hlist_for_each_entry_rcu(x6spi,
 			     &xfrm6_tn->spi_byaddr[xfrm6_tunnel_spi_hash_byaddr(saddr)],
 			     list_byaddr) {
 		if (xfrm6_addr_equal(&x6spi->addr, saddr))
@@ -120,9 +119,8 @@ static int __xfrm6_tunnel_spi_check(struct net *net, u32 spi)
 	struct xfrm6_tunnel_net *xfrm6_tn = xfrm6_tunnel_pernet(net);
 	struct xfrm6_tunnel_spi *x6spi;
 	int index = xfrm6_tunnel_spi_hash_byspi(spi);
-	struct hlist_node *pos;
 
-	hlist_for_each_entry(x6spi, pos,
+	hlist_for_each_entry(x6spi,
 			     &xfrm6_tn->spi_byspi[index],
 			     list_byspi) {
 		if (x6spi->spi == spi)
@@ -203,11 +201,11 @@ static void xfrm6_tunnel_free_spi(struct net *net, xfrm_address_t *saddr)
 {
 	struct xfrm6_tunnel_net *xfrm6_tn = xfrm6_tunnel_pernet(net);
 	struct xfrm6_tunnel_spi *x6spi;
-	struct hlist_node *pos, *n;
+	struct hlist_node *n;
 
 	spin_lock_bh(&xfrm6_tunnel_spi_lock);
 
-	hlist_for_each_entry_safe(x6spi, pos, n,
+	hlist_for_each_entry_safe(x6spi, n,
 				  &xfrm6_tn->spi_byaddr[xfrm6_tunnel_spi_hash_byaddr(saddr)],
 				  list_byaddr)
 	{