ftrace: Provide API to use global filtering for ftrace ops

Currently the global_ops filtering hash is not available to outside users
registering for function tracing. Provide an API for those users to be
able to choose global filtering.

This is in preparation for pstore's ftrace feature to be able to
use the global filters.

Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Anton Vorontsov <anton@enomsg.org>
Cc: Colin Cross <ccross@android.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Tony Luck <tony.luck@intel.com>
Signed-off-by: Joel Fernandes <joelaf@google.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Kees Cook <keescook@chromium.org>

1 files changed, 2 insertions, 0 deletions

diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h
index b3d34d3e0e7e..d4a884db16a3 100644
--- a/include/linux/ftrace.h
+++ b/include/linux/ftrace.h
@@ -398,6 +398,7 @@ int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf,
 void ftrace_set_global_filter(unsigned char *buf, int len, int reset);
 void ftrace_set_global_notrace(unsigned char *buf, int len, int reset);
 void ftrace_free_filter(struct ftrace_ops *ops);
+void ftrace_ops_set_global_filter(struct ftrace_ops *ops);
 
 int register_ftrace_command(struct ftrace_func_command *cmd);
 int unregister_ftrace_command(struct ftrace_func_command *cmd);
@@ -645,6 +646,7 @@ static inline unsigned long ftrace_location(unsigned long ip)
 #define ftrace_set_filter(ops, buf, len, reset) ({ -ENODEV; })
 #define ftrace_set_notrace(ops, buf, len, reset) ({ -ENODEV; })
 #define ftrace_free_filter(ops) do { } while (0)
+#define ftrace_ops_set_global_filter(ops) do { } while (0)
 
 static inline ssize_t ftrace_filter_write(struct file *file, const char __user *ubuf,
                             size_t cnt, loff_t *ppos) { return -ENODEV; }