diff --git a/include/linux/notifier.h b/include/linux/notifier.h
index 10a43ed0527eb0215acba9078786105fb1f8b8de..e34221bf8946264be061c16ee56bd57ecbb4f7f6 100644
--- a/include/linux/notifier.h
+++ b/include/linux/notifier.h
@@ -112,32 +112,40 @@ extern void srcu_init_notifier_head(struct srcu_notifier_head *nh);
#ifdef __KERNEL__
-extern int atomic_notifier_chain_register(struct atomic_notifier_head *,
- struct notifier_block *);
-extern int blocking_notifier_chain_register(struct blocking_notifier_head *,
- struct notifier_block *);
-extern int raw_notifier_chain_register(struct raw_notifier_head *,
- struct notifier_block *);
-extern int srcu_notifier_chain_register(struct srcu_notifier_head *,
- struct notifier_block *);
-
-extern int atomic_notifier_chain_unregister(struct atomic_notifier_head *,
- struct notifier_block *);
-extern int blocking_notifier_chain_unregister(struct blocking_notifier_head *,
- struct notifier_block *);
-extern int raw_notifier_chain_unregister(struct raw_notifier_head *,
- struct notifier_block *);
-extern int srcu_notifier_chain_unregister(struct srcu_notifier_head *,
- struct notifier_block *);
-
-extern int atomic_notifier_call_chain(struct atomic_notifier_head *,
+extern int atomic_notifier_chain_register(struct atomic_notifier_head *nh,
+ struct notifier_block *nb);
+extern int blocking_notifier_chain_register(struct blocking_notifier_head *nh,
+ struct notifier_block *nb);
+extern int raw_notifier_chain_register(struct raw_notifier_head *nh,
+ struct notifier_block *nb);
+extern int srcu_notifier_chain_register(struct srcu_notifier_head *nh,
+ struct notifier_block *nb);
+
+extern int atomic_notifier_chain_unregister(struct atomic_notifier_head *nh,
+ struct notifier_block *nb);
+extern int blocking_notifier_chain_unregister(struct blocking_notifier_head *nh,
+ struct notifier_block *nb);
+extern int raw_notifier_chain_unregister(struct raw_notifier_head *nh,
+ struct notifier_block *nb);
+extern int srcu_notifier_chain_unregister(struct srcu_notifier_head *nh,
+ struct notifier_block *nb);
+
+extern int atomic_notifier_call_chain(struct atomic_notifier_head *nh,
unsigned long val, void *v);
-extern int blocking_notifier_call_chain(struct blocking_notifier_head *,
+extern int __atomic_notifier_call_chain(struct atomic_notifier_head *nh,
+ unsigned long val, void *v, int nr_to_call, int *nr_calls);
+extern int blocking_notifier_call_chain(struct blocking_notifier_head *nh,
unsigned long val, void *v);
-extern int raw_notifier_call_chain(struct raw_notifier_head *,
+extern int __blocking_notifier_call_chain(struct blocking_notifier_head *nh,
+ unsigned long val, void *v, int nr_to_call, int *nr_calls);
+extern int raw_notifier_call_chain(struct raw_notifier_head *nh,
unsigned long val, void *v);
-extern int srcu_notifier_call_chain(struct srcu_notifier_head *,
+extern int __raw_notifier_call_chain(struct raw_notifier_head *nh,
+ unsigned long val, void *v, int nr_to_call, int *nr_calls);
+extern int srcu_notifier_call_chain(struct srcu_notifier_head *nh,
unsigned long val, void *v);
+extern int __srcu_notifier_call_chain(struct srcu_notifier_head *nh,
+ unsigned long val, void *v, int nr_to_call, int *nr_calls);
#define NOTIFY_DONE 0x0000 /* Don't care */
#define NOTIFY_OK 0x0001 /* Suits me */
diff --git a/kernel/sys.c b/kernel/sys.c
index 8ecfe34737796a494a3cb73277ad822823fcea51..d4985df21b60cd7b4b14a14c9070d048c7da1a7c 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -134,19 +134,39 @@ static int notifier_chain_unregister(struct notifier_block **nl,
return -ENOENT;
}
+/**
+ * notifier_call_chain - Informs the registered notifiers about an event.
+ * @nl: Pointer to head of the blocking notifier chain
+ * @val: Value passed unmodified to notifier function
+ * @v: Pointer passed unmodified to notifier function
+ * @nr_to_call: Number of notifier functions to be called. Don't care
+ * value of this parameter is -1.
+ * @nr_calls: Records the number of notifications sent. Don't care
+ * value of this field is NULL.
+ * @returns: notifier_call_chain returns the value returned by the
+ * last notifier function called.
+ */
+
static int __kprobes notifier_call_chain(struct notifier_block **nl,
- unsigned long val, void *v)
+ unsigned long val, void *v,
+ int nr_to_call, int *nr_calls)
{
int ret = NOTIFY_DONE;
struct notifier_block *nb, *next_nb;
nb = rcu_dereference(*nl);
- while (nb) {
+
+ while (nb && nr_to_call) {
next_nb = rcu_dereference(nb->next);
ret = nb->notifier_call(nb, val, v);
+
+ if (nr_calls)
+ (*nr_calls)++;
+
if ((ret & NOTIFY_STOP_MASK) == NOTIFY_STOP_MASK)
break;
nb = next_nb;
+ nr_to_call--;
}
return ret;
}
@@ -205,10 +225,12 @@ int atomic_notifier_chain_unregister(struct atomic_notifier_head *nh,
EXPORT_SYMBOL_GPL(atomic_notifier_chain_unregister);
/**
- * atomic_notifier_call_chain - Call functions in an atomic notifier chain
+ * __atomic_notifier_call_chain - Call functions in an atomic notifier chain
* @nh: Pointer to head of the atomic notifier chain
* @val: Value passed unmodified to notifier function
* @v: Pointer passed unmodified to notifier function
+ * @nr_to_call: See the comment for notifier_call_chain.
+ * @nr_calls: See the comment for notifier_call_chain.
*
* Calls each function in a notifier chain in turn. The functions
* run in an atomic context, so they must not block.
@@ -222,19 +244,27 @@ EXPORT_SYMBOL_GPL(atomic_notifier_chain_unregister);
* of the last notifier function called.
*/
-int __kprobes atomic_notifier_call_chain(struct atomic_notifier_head *nh,
- unsigned long val, void *v)
+int __kprobes __atomic_notifier_call_chain(struct atomic_notifier_head *nh,
+ unsigned long val, void *v,
+ int nr_to_call, int *nr_calls)
{
int ret;
rcu_read_lock();
- ret = notifier_call_chain(&nh->head, val, v);
+ ret = notifier_call_chain(&nh->head, val, v, nr_to_call, nr_calls);
rcu_read_unlock();
return ret;
}
-EXPORT_SYMBOL_GPL(atomic_notifier_call_chain);
+EXPORT_SYMBOL_GPL(__atomic_notifier_call_chain);
+
+int __kprobes atomic_notifier_call_chain(struct atomic_notifier_head *nh,
+ unsigned long val, void *v)
+{
+ return __atomic_notifier_call_chain(nh, val, v, -1, NULL);
+}
+EXPORT_SYMBOL_GPL(atomic_notifier_call_chain);
/*
* Blocking notifier chain routines. All access to the chain is
* synchronized by an rwsem.
@@ -304,10 +334,12 @@ int blocking_notifier_chain_unregister(struct blocking_notifier_head *nh,
EXPORT_SYMBOL_GPL(blocking_notifier_chain_unregister);
/**
- * blocking_notifier_call_chain - Call functions in a blocking notifier chain
+ * __blocking_notifier_call_chain - Call functions in a blocking notifier chain
* @nh: Pointer to head of the blocking notifier chain
* @val: Value passed unmodified to notifier function
* @v: Pointer passed unmodified to notifier function
+ * @nr_to_call: See comment for notifier_call_chain.
+ * @nr_calls: See comment for notifier_call_chain.
*
* Calls each function in a notifier chain in turn. The functions
* run in a process context, so they are allowed to block.
@@ -320,8 +352,9 @@ EXPORT_SYMBOL_GPL(blocking_notifier_chain_unregister);
* of the last notifier function called.
*/
-int blocking_notifier_call_chain(struct blocking_notifier_head *nh,
- unsigned long val, void *v)
+int __blocking_notifier_call_chain(struct blocking_notifier_head *nh,
+ unsigned long val, void *v,
+ int nr_to_call, int *nr_calls)
{
int ret = NOTIFY_DONE;
@@ -332,12 +365,19 @@ int blocking_notifier_call_chain(struct blocking_notifier_head *nh,
*/
if (rcu_dereference(nh->head)) {
down_read(&nh->rwsem);
- ret = notifier_call_chain(&nh->head, val, v);
+ ret = notifier_call_chain(&nh->head, val, v, nr_to_call,
+ nr_calls);
up_read(&nh->rwsem);
}
return ret;
}
+EXPORT_SYMBOL_GPL(__blocking_notifier_call_chain);
+int blocking_notifier_call_chain(struct blocking_notifier_head *nh,
+ unsigned long val, void *v)
+{
+ return __blocking_notifier_call_chain(nh, val, v, -1, NULL);
+}
EXPORT_SYMBOL_GPL(blocking_notifier_call_chain);
/*
@@ -383,10 +423,12 @@ int raw_notifier_chain_unregister(struct raw_notifier_head *nh,
EXPORT_SYMBOL_GPL(raw_notifier_chain_unregister);
/**
- * raw_notifier_call_chain - Call functions in a raw notifier chain
+ * __raw_notifier_call_chain - Call functions in a raw notifier chain
* @nh: Pointer to head of the raw notifier chain
* @val: Value passed unmodified to notifier function
* @v: Pointer passed unmodified to notifier function
+ * @nr_to_call: See comment for notifier_call_chain.
+ * @nr_calls: See comment for notifier_call_chain
*
* Calls each function in a notifier chain in turn. The functions
* run in an undefined context.
@@ -400,10 +442,19 @@ EXPORT_SYMBOL_GPL(raw_notifier_chain_unregister);
* of the last notifier function called.
*/
+int __raw_notifier_call_chain(struct raw_notifier_head *nh,
+ unsigned long val, void *v,
+ int nr_to_call, int *nr_calls)
+{
+ return notifier_call_chain(&nh->head, val, v, nr_to_call, nr_calls);
+}
+
+EXPORT_SYMBOL_GPL(__raw_notifier_call_chain);
+
int raw_notifier_call_chain(struct raw_notifier_head *nh,
unsigned long val, void *v)
{
- return notifier_call_chain(&nh->head, val, v);
+ return __raw_notifier_call_chain(nh, val, v, -1, NULL);
}
EXPORT_SYMBOL_GPL(raw_notifier_call_chain);
@@ -478,10 +529,12 @@ int srcu_notifier_chain_unregister(struct srcu_notifier_head *nh,
EXPORT_SYMBOL_GPL(srcu_notifier_chain_unregister);
/**
- * srcu_notifier_call_chain - Call functions in an SRCU notifier chain
+ * __srcu_notifier_call_chain - Call functions in an SRCU notifier chain
* @nh: Pointer to head of the SRCU notifier chain
* @val: Value passed unmodified to notifier function
* @v: Pointer passed unmodified to notifier function
+ * @nr_to_call: See comment for notifier_call_chain.
+ * @nr_calls: See comment for notifier_call_chain
*
* Calls each function in a notifier chain in turn. The functions
* run in a process context, so they are allowed to block.
@@ -494,18 +547,25 @@ EXPORT_SYMBOL_GPL(srcu_notifier_chain_unregister);
* of the last notifier function called.
*/
-int srcu_notifier_call_chain(struct srcu_notifier_head *nh,
- unsigned long val, void *v)
+int __srcu_notifier_call_chain(struct srcu_notifier_head *nh,
+ unsigned long val, void *v,
+ int nr_to_call, int *nr_calls)
{
int ret;
int idx;
idx = srcu_read_lock(&nh->srcu);
- ret = notifier_call_chain(&nh->head, val, v);
+ ret = notifier_call_chain(&nh->head, val, v, nr_to_call, nr_calls);
srcu_read_unlock(&nh->srcu, idx);
return ret;
}
+EXPORT_SYMBOL_GPL(__srcu_notifier_call_chain);
+int srcu_notifier_call_chain(struct srcu_notifier_head *nh,
+ unsigned long val, void *v)
+{
+ return __srcu_notifier_call_chain(nh, val, v, -1, NULL);
+}
EXPORT_SYMBOL_GPL(srcu_notifier_call_chain);
/**