This patch restores the RCU marking on bucket_table->buckets as
it really does need RCU protection. Its removal had led to a fatal
bug.
Signed-off-by: Herbert Xu <herb...@gondor.apana.org.au>
diff --git a/include/linux/rhashtable.h b/include/linux/rhashtable.h
index e3def7bbe932..83ad875a7ea2 100644
--- a/include/linux/rhashtable.h
+++ b/include/linux/rhashtable.h
@@ -84,7 +84,7 @@ struct bucket_table {
struct lockdep_map dep_map;
- struct rhash_lock_head *buckets[] ____cacheline_aligned_in_smp;
+ struct rhash_lock_head __rcu *buckets[] ____cacheline_aligned_in_smp;
};
/*
@@ -261,13 +261,12 @@ void rhashtable_free_and_destroy(struct rhashtable *ht,
void *arg);
void rhashtable_destroy(struct rhashtable *ht);
-struct rhash_lock_head **rht_bucket_nested(const struct bucket_table *tbl,
- unsigned int hash);
-struct rhash_lock_head **__rht_bucket_nested(const struct bucket_table *tbl,
- unsigned int hash);
-struct rhash_lock_head **rht_bucket_nested_insert(struct rhashtable *ht,
- struct bucket_table *tbl,
- unsigned int hash);
+struct rhash_lock_head __rcu **rht_bucket_nested(
+ const struct bucket_table *tbl, unsigned int hash);
+struct rhash_lock_head __rcu **__rht_bucket_nested(
+ const struct bucket_table *tbl, unsigned int hash);
+struct rhash_lock_head __rcu **rht_bucket_nested_insert(
+ struct rhashtable *ht, struct bucket_table *tbl, unsigned int hash);
#define rht_dereference(p, ht) \
rcu_dereference_protected(p, lockdep_rht_mutex_is_held(ht))
@@ -284,21 +283,21 @@ struct rhash_lock_head **rht_bucket_nested_insert(struct
rhashtable *ht,
#define rht_entry(tpos, pos, member) \
({ tpos = container_of(pos, typeof(*tpos), member); 1; })
-static inline struct rhash_lock_head *const *rht_bucket(
+static inline struct rhash_lock_head __rcu *const *rht_bucket(
const struct bucket_table *tbl, unsigned int hash)
{
return unlikely(tbl->nest) ? rht_bucket_nested(tbl, hash) :
&tbl->buckets[hash];
}
-static inline struct rhash_lock_head **rht_bucket_var(
+static inline struct rhash_lock_head __rcu **rht_bucket_var(
struct bucket_table *tbl, unsigned int hash)
{
return unlikely(tbl->nest) ? __rht_bucket_nested(tbl, hash) :
&tbl->buckets[hash];
}
-static inline struct rhash_lock_head **rht_bucket_insert(
+static inline struct rhash_lock_head __rcu **rht_bucket_insert(
struct rhashtable *ht, struct bucket_table *tbl, unsigned int hash)
{
return unlikely(tbl->nest) ? rht_bucket_nested_insert(ht, tbl, hash) :
@@ -325,7 +324,7 @@ static inline struct rhash_lock_head **rht_bucket_insert(
*/
static inline void rht_lock(struct bucket_table *tbl,
- struct rhash_lock_head **bkt)
+ struct rhash_lock_head __rcu **bkt)
{
local_bh_disable();
bit_spin_lock(0, (unsigned long *)bkt);
@@ -333,7 +332,7 @@ static inline void rht_lock(struct bucket_table *tbl,
}
static inline void rht_lock_nested(struct bucket_table *tbl,
- struct rhash_lock_head **bucket,
+ struct rhash_lock_head __rcu **bucket,
unsigned int subclass)
{
local_bh_disable();
@@ -342,7 +341,7 @@ static inline void rht_lock_nested(struct bucket_table *tbl,
}
static inline void rht_unlock(struct bucket_table *tbl,
- struct rhash_lock_head **bkt)
+ struct rhash_lock_head __rcu **bkt)
{
lock_map_release(&tbl->dep_map);
bit_spin_unlock(0, (unsigned long *)bkt);
@@ -365,48 +364,41 @@ static inline struct rhash_head *__rht_ptr(
* access is guaranteed, such as when destroying the table.
*/
static inline struct rhash_head *rht_ptr_rcu(
- struct rhash_lock_head *const *p)
+ struct rhash_lock_head __rcu *const *bkt)
{
- struct rhash_lock_head __rcu *const *bkt = (void *)p;
return __rht_ptr(rcu_dereference(*bkt), bkt);
}
static inline struct rhash_head *rht_ptr(
- struct rhash_lock_head *const *p,
+ struct rhash_lock_head __rcu *const *bkt,
struct bucket_table *tbl,
unsigned int hash)
{
- struct rhash_lock_head __rcu *const *bkt = (void *)p;
return __rht_ptr(rht_dereference_bucket(*bkt, tbl, hash), bkt);
}
static inline struct rhash_head *rht_ptr_exclusive(
- struct rhash_lock_head *const *p)
+ struct rhash_lock_head __rcu *const *bkt)
{
- struct rhash_lock_head __rcu *const *bkt = (void *)p;
return __rht_ptr(rcu_dereference_protected(*bkt, 1), bkt);
}
-static inline void rht_assign_locked(struct rhash_lock_head **bkt,
+static inline void rht_assign_locked(struct rhash_lock_head __rcu **bkt,
struct rhash_head *obj)
{
- struct rhash_head __rcu **p = (struct rhash_head __rcu **)bkt;
-
if (rht_is_a_nulls(obj))
obj = NULL;
- rcu_assign_pointer(*p, (void *)((unsigned long)obj | BIT(0)));
+ rcu_assign_pointer(*bkt, (void *)((unsigned long)obj | BIT(0)));
}
static inline void rht_assign_unlock(struct bucket_table *tbl,
- struct rhash_lock_head **bkt,
+ struct rhash_lock_head __rcu **bkt,
struct rhash_head *obj)
{
- struct rhash_head __rcu **p = (struct rhash_head __rcu **)bkt;
-
if (rht_is_a_nulls(obj))
obj = NULL;
lock_map_release(&tbl->dep_map);
- rcu_assign_pointer(*p, obj);
+ rcu_assign_pointer(*bkt, (void *)obj);
preempt_enable();
__release(bitlock);
local_bh_enable();
@@ -594,7 +586,7 @@ static inline struct rhash_head *__rhashtable_lookup(
.ht = ht,
.key = key,
};
- struct rhash_lock_head *const *bkt;
+ struct rhash_lock_head __rcu *const *bkt;
struct bucket_table *tbl;
struct rhash_head *he;
unsigned int hash;
@@ -710,7 +702,7 @@ static inline void *__rhashtable_insert_fast(
.ht = ht,
.key = key,
};
- struct rhash_lock_head **bkt;
+ struct rhash_lock_head __rcu **bkt;
struct rhash_head __rcu **pprev;
struct bucket_table *tbl;
struct rhash_head *head;
@@ -996,7 +988,7 @@ static inline int __rhashtable_remove_fast_one(
struct rhash_head *obj, const struct rhashtable_params params,
bool rhlist)
{
- struct rhash_lock_head **bkt;
+ struct rhash_lock_head __rcu **bkt;
struct rhash_head __rcu **pprev;
struct rhash_head *he;
unsigned int hash;
@@ -1148,7 +1140,7 @@ static inline int __rhashtable_replace_fast(
struct rhash_head *obj_old, struct rhash_head *obj_new,
const struct rhashtable_params params)
{
- struct rhash_lock_head **bkt;
+ struct rhash_lock_head __rcu **bkt;
struct rhash_head __rcu **pprev;
struct rhash_head *he;
unsigned int hash;
diff --git a/lib/rhashtable.c b/lib/rhashtable.c
index 9f6890aedd1a..c949c1e3b87c 100644
--- a/lib/rhashtable.c
+++ b/lib/rhashtable.c
@@ -31,7 +31,7 @@
union nested_table {
union nested_table __rcu *table;
- struct rhash_lock_head *bucket;
+ struct rhash_lock_head __rcu *bucket;
};
static u32 head_hashfn(struct rhashtable *ht,
@@ -222,7 +222,7 @@ static struct bucket_table *rhashtable_last_table(struct
rhashtable *ht,
}
static int rhashtable_rehash_one(struct rhashtable *ht,
- struct rhash_lock_head **bkt,
+ struct rhash_lock_head __rcu **bkt,
unsigned int old_hash)
{
struct bucket_table *old_tbl = rht_dereference(ht->tbl, ht);
@@ -275,7 +275,7 @@ static int rhashtable_rehash_chain(struct rhashtable *ht,
unsigned int old_hash)
{
struct bucket_table *old_tbl = rht_dereference(ht->tbl, ht);
- struct rhash_lock_head **bkt = rht_bucket_var(old_tbl, old_hash);
+ struct rhash_lock_head __rcu **bkt = rht_bucket_var(old_tbl, old_hash);
int err;
if (!bkt)
@@ -485,7 +485,7 @@ static int rhashtable_insert_rehash(struct rhashtable *ht,
}
static void *rhashtable_lookup_one(struct rhashtable *ht,
- struct rhash_lock_head **bkt,
+ struct rhash_lock_head __rcu **bkt,
struct bucket_table *tbl, unsigned int hash,
const void *key, struct rhash_head *obj)
{
@@ -535,12 +535,10 @@ static void *rhashtable_lookup_one(struct rhashtable *ht,
return ERR_PTR(-ENOENT);
}
-static struct bucket_table *rhashtable_insert_one(struct rhashtable *ht,
- struct rhash_lock_head **bkt,
- struct bucket_table *tbl,
- unsigned int hash,
- struct rhash_head *obj,
- void *data)
+static struct bucket_table *rhashtable_insert_one(
+ struct rhashtable *ht, struct rhash_lock_head __rcu **bkt,
+ struct bucket_table *tbl, unsigned int hash, struct rhash_head *obj,
+ void *data)
{
struct bucket_table *new_tbl;
struct rhash_head *head;
@@ -591,7 +589,7 @@ static void *rhashtable_try_insert(struct rhashtable *ht,
const void *key,
{
struct bucket_table *new_tbl;
struct bucket_table *tbl;
- struct rhash_lock_head **bkt;
+ struct rhash_lock_head __rcu **bkt;
unsigned int hash;
void *data;
@@ -1173,8 +1171,8 @@ void rhashtable_destroy(struct rhashtable *ht)
}
EXPORT_SYMBOL_GPL(rhashtable_destroy);
-struct rhash_lock_head **__rht_bucket_nested(const struct bucket_table *tbl,
- unsigned int hash)
+struct rhash_lock_head __rcu **__rht_bucket_nested(
+ const struct bucket_table *tbl, unsigned int hash)
{
const unsigned int shift = PAGE_SHIFT - ilog2(sizeof(void *));
unsigned int index = hash & ((1 << tbl->nest) - 1);
@@ -1202,10 +1200,10 @@ struct rhash_lock_head **__rht_bucket_nested(const
struct bucket_table *tbl,
}
EXPORT_SYMBOL_GPL(__rht_bucket_nested);
-struct rhash_lock_head **rht_bucket_nested(const struct bucket_table *tbl,
- unsigned int hash)
+struct rhash_lock_head __rcu **rht_bucket_nested(
+ const struct bucket_table *tbl, unsigned int hash)
{
- static struct rhash_lock_head *rhnull;
+ static struct rhash_lock_head __rcu *rhnull;
if (!rhnull)
INIT_RHT_NULLS_HEAD(rhnull);
@@ -1213,9 +1211,8 @@ struct rhash_lock_head **rht_bucket_nested(const struct
bucket_table *tbl,
}
EXPORT_SYMBOL_GPL(rht_bucket_nested);
-struct rhash_lock_head **rht_bucket_nested_insert(struct rhashtable *ht,
- struct bucket_table *tbl,
- unsigned int hash)
+struct rhash_lock_head __rcu **rht_bucket_nested_insert(
+ struct rhashtable *ht, struct bucket_table *tbl, unsigned int hash)
{
const unsigned int shift = PAGE_SHIFT - ilog2(sizeof(void *));
unsigned int index = hash & ((1 << tbl->nest) - 1);
--
Email: Herbert Xu <herb...@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt
