[PATCH 34/45] C++: Fix up use of LIST_POISON*

From: David Howells
Date: Sun Apr 01 2018 - 16:43:49 EST


Implicitly casting void* to a non-void pointer is frowned upon in C++,
though -fpermissive causes it to be accepted. Fix up LIST_POISON1/2
somewhat to handle this a bit better.

Signed-off-by: David Howells <dhowells@xxxxxxxxxx>
---

include/linux/list.h | 8 ++++----
include/linux/list_bl.h | 4 ++--
include/linux/list_nulls.h | 2 +-
include/linux/poison.h | 6 ++++--
include/linux/rculist.h | 4 ++--
include/linux/rculist_bl.h | 2 +-
6 files changed, 14 insertions(+), 12 deletions(-)

diff --git a/include/linux/list.h b/include/linux/list.h
index 4b129df4d46b..6aa933e4b109 100644
--- a/include/linux/list.h
+++ b/include/linux/list.h
@@ -123,8 +123,8 @@ static inline void __list_del_entry(struct list_head *entry)
static inline void list_del(struct list_head *entry)
{
__list_del_entry(entry);
- entry->next = LIST_POISON1;
- entry->prev = LIST_POISON2;
+ entry->next = static_cast<struct list_head *>(LIST_POISON1);
+ entry->prev = static_cast<struct list_head *>(LIST_POISON2);
}

/**
@@ -654,8 +654,8 @@ static inline void __hlist_del(struct hlist_node *n)
static inline void hlist_del(struct hlist_node *n)
{
__hlist_del(n);
- n->next = LIST_POISON1;
- n->pprev = LIST_POISON2;
+ n->next = HLIST_POISON1;
+ n->pprev = HLIST_POISON2;
}

static inline void hlist_del_init(struct hlist_node *n)
diff --git a/include/linux/list_bl.h b/include/linux/list_bl.h
index 3fc2cc57ba1b..474c87c2e72e 100644
--- a/include/linux/list_bl.h
+++ b/include/linux/list_bl.h
@@ -105,8 +105,8 @@ static inline void __hlist_bl_del(struct hlist_bl_node *n)
static inline void hlist_bl_del(struct hlist_bl_node *n)
{
__hlist_bl_del(n);
- n->next = LIST_POISON1;
- n->pprev = LIST_POISON2;
+ n->next = ((struct hlist_bl_node *) (0x100 + POISON_POINTER_DELTA));
+ n->pprev = ((struct hlist_bl_node **) (0x200 + POISON_POINTER_DELTA));
}

static inline void hlist_bl_del_init(struct hlist_bl_node *n)
diff --git a/include/linux/list_nulls.h b/include/linux/list_nulls.h
index 3ef96743db8d..6c471fd62c9c 100644
--- a/include/linux/list_nulls.h
+++ b/include/linux/list_nulls.h
@@ -91,7 +91,7 @@ static inline void __hlist_nulls_del(struct hlist_nulls_node *n)
static inline void hlist_nulls_del(struct hlist_nulls_node *n)
{
__hlist_nulls_del(n);
- n->pprev = LIST_POISON2;
+ n->pprev = (struct hlist_nulls_node **)LIST_POISON2;
}

/**
diff --git a/include/linux/poison.h b/include/linux/poison.h
index 15927ebc22f2..21544c2bf1a7 100644
--- a/include/linux/poison.h
+++ b/include/linux/poison.h
@@ -20,8 +20,10 @@
* under normal circumstances, used to verify that nobody uses
* non-initialized list entries.
*/
-#define LIST_POISON1 ((void *) 0x100 + POISON_POINTER_DELTA)
-#define LIST_POISON2 ((void *) 0x200 + POISON_POINTER_DELTA)
+#define LIST_POISON1 ((struct list_head *) (0x100 + POISON_POINTER_DELTA))
+#define LIST_POISON2 ((struct list_head *) (0x200 + POISON_POINTER_DELTA))
+#define HLIST_POISON1 ((struct hlist_node *) (0x100 + POISON_POINTER_DELTA))
+#define HLIST_POISON2 ((struct hlist_node **) (0x200 + POISON_POINTER_DELTA))

/********** include/linux/timer.h **********/
/*
diff --git a/include/linux/rculist.h b/include/linux/rculist.h
index 127f534fec94..d7b6a0a697c8 100644
--- a/include/linux/rculist.h
+++ b/include/linux/rculist.h
@@ -425,7 +425,7 @@ static inline void list_splice_tail_init_rcu(struct list_head *list,
static inline void hlist_del_rcu(struct hlist_node *n)
{
__hlist_del(n);
- n->pprev = LIST_POISON2;
+ n->pprev = HLIST_POISON2;
}

/**
@@ -445,7 +445,7 @@ static inline void hlist_replace_rcu(struct hlist_node *old,
rcu_assign_pointer(*(struct hlist_node __rcu **)new->pprev, new);
if (next)
new->next->pprev = &new->next;
- old->pprev = LIST_POISON2;
+ old->pprev = HLIST_POISON2;
}

/*
diff --git a/include/linux/rculist_bl.h b/include/linux/rculist_bl.h
index 66e73ec1aa99..e5a2c59deb6d 100644
--- a/include/linux/rculist_bl.h
+++ b/include/linux/rculist_bl.h
@@ -74,7 +74,7 @@ static inline void hlist_bl_del_init_rcu(struct hlist_bl_node *n)
static inline void hlist_bl_del_rcu(struct hlist_bl_node *n)
{
__hlist_bl_del(n);
- n->pprev = LIST_POISON2;
+ n->pprev = ((struct hlist_bl_node **) (0x200 + POISON_POINTER_DELTA));
}

/**