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, 8 insertions, 11 deletions

diff --git a/drivers/gpu/drm/drm_hashtab.c b/drivers/gpu/drm/drm_hashtab.c
index 80254547a3f8..7e4bae760e27 100644
--- a/drivers/gpu/drm/drm_hashtab.c
+++ b/drivers/gpu/drm/drm_hashtab.c
@@ -60,14 +60,13 @@ void drm_ht_verbose_list(struct drm_open_hash *ht, unsigned long key)
 {
         struct drm_hash_item *entry;
         struct hlist_head *h_list;
-        struct hlist_node *list;
         unsigned int hashed_key;
         int count = 0;
 
         hashed_key = hash_long(key, ht->order);
         DRM_DEBUG("Key is 0x%08lx, Hashed key is 0x%08x\n", key, hashed_key);
         h_list = &ht->table[hashed_key];
-        hlist_for_each_entry(entry, list, h_list, head)
+        hlist_for_each_entry(entry, h_list, head)
                 DRM_DEBUG("count %d, key: 0x%08lx\n", count++, entry->key);
 }
 
@@ -76,14 +75,13 @@ static struct hlist_node *drm_ht_find_key(struct drm_open_hash *ht,
 {
         struct drm_hash_item *entry;
         struct hlist_head *h_list;
-        struct hlist_node *list;
         unsigned int hashed_key;
 
         hashed_key = hash_long(key, ht->order);
         h_list = &ht->table[hashed_key];
-        hlist_for_each_entry(entry, list, h_list, head) {
+        hlist_for_each_entry(entry, h_list, head) {
                 if (entry->key == key)
-                        return list;
+                        return &entry->head;
                 if (entry->key > key)
                         break;
         }
@@ -95,14 +93,13 @@ static struct hlist_node *drm_ht_find_key_rcu(struct drm_open_hash *ht,
 {
         struct drm_hash_item *entry;
         struct hlist_head *h_list;
-        struct hlist_node *list;
         unsigned int hashed_key;
 
         hashed_key = hash_long(key, ht->order);
         h_list = &ht->table[hashed_key];
-        hlist_for_each_entry_rcu(entry, list, h_list, head) {
+        hlist_for_each_entry_rcu(entry, h_list, head) {
                 if (entry->key == key)
-                        return list;
+                        return &entry->head;
                 if (entry->key > key)
                         break;
         }
@@ -113,19 +110,19 @@ int drm_ht_insert_item(struct drm_open_hash *ht, struct drm_hash_item *item)
 {
         struct drm_hash_item *entry;
         struct hlist_head *h_list;
-        struct hlist_node *list, *parent;
+        struct hlist_node *parent;
         unsigned int hashed_key;
         unsigned long key = item->key;
 
         hashed_key = hash_long(key, ht->order);
         h_list = &ht->table[hashed_key];
         parent = NULL;
-        hlist_for_each_entry(entry, list, h_list, head) {
+        hlist_for_each_entry(entry, h_list, head) {
                 if (entry->key == key)
                         return -EINVAL;
                 if (entry->key > key)
                         break;
-                parent = list;
+                parent = &entry->head;
         }
         if (parent) {
                 hlist_add_after_rcu(parent, &item->head);