tracing: Add generic tracing_lseek() function

Trace event triggers added a lseek that uses the ftrace_filter_lseek()
function. Unfortunately, when function tracing is not configured in
that function is not defined and the kernel fails to build.

This is the second time that function was added to a file ops and
it broke the build due to requiring special config dependencies.

Make a generic tracing_lseek() that all the tracing utilities may
use.

Also, modify the old ftrace_filter_lseek() to return 0 instead of
1 on WRONLY. Not sure why it was a 1 as that does not make sense.

This also changes the old tracing_seek() to modify the file pos
pointer on WRONLY as well.

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Tested-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Acked-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

1 files changed, 1 insertions, 1 deletions

diff --git a/kernel/trace/trace_events_trigger.c b/kernel/trace/trace_events_trigger.c
index f5b3f780fda4..12ac8a5d4d95 100644
--- a/kernel/trace/trace_events_trigger.c
+++ b/kernel/trace/trace_events_trigger.c
@@ -281,7 +281,7 @@ const struct file_operations event_trigger_fops = {
 	.open = event_trigger_open,
 	.read = seq_read,
 	.write = event_trigger_write,
-	.llseek = ftrace_filter_lseek,
+	.llseek = tracing_lseek,
 	.release = event_trigger_release,
 };