1 files changed, 65 insertions, 52 deletions

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 94f1b9124939..26ee280f852b 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -304,6 +304,17 @@ void trace_array_put(struct trace_array *this_tr)
         mutex_unlock(&trace_types_lock);
 }
 
+int tracing_check_open_get_tr(struct trace_array *tr)
+{
+        if (tracing_disabled)
+                return -ENODEV;
+
+        if (tr && trace_array_get(tr) < 0)
+                return -ENODEV;
+
+        return 0;
+}
+
 int call_filter_check_discard(struct trace_event_call *call, void *rec,
                               struct ring_buffer *buffer,
                               struct ring_buffer_event *event)
@@ -4140,8 +4151,11 @@ release:
 
 int tracing_open_generic(struct inode *inode, struct file *filp)
 {
-        if (tracing_disabled)
-                return -ENODEV;
+        int ret;
+
+        ret = tracing_check_open_get_tr(NULL);
+        if (ret)
+                return ret;
 
         filp->private_data = inode->i_private;
         return 0;
@@ -4159,12 +4173,11 @@ bool tracing_is_disabled(void)
 int tracing_open_generic_tr(struct inode *inode, struct file *filp)
 {
         struct trace_array *tr = inode->i_private;
+        int ret;
 
-        if (tracing_disabled)
-                return -ENODEV;
-
-        if (trace_array_get(tr) < 0)
-                return -ENODEV;
+        ret = tracing_check_open_get_tr(tr);
+        if (ret)
+                return ret;
 
         filp->private_data = inode->i_private;
 
@@ -4233,10 +4246,11 @@ static int tracing_open(struct inode *inode, struct file *file)
 {
         struct trace_array *tr = inode->i_private;
         struct trace_iterator *iter;
-        int ret = 0;
+        int ret;
 
-        if (trace_array_get(tr) < 0)
-                return -ENODEV;
+        ret = tracing_check_open_get_tr(tr);
+        if (ret)
+                return ret;
 
         /* If this file was open for write, then erase contents */
         if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) {
@@ -4352,11 +4366,9 @@ static int show_traces_open(struct inode *inode, struct file *file)
         struct seq_file *m;
         int ret;
 
-        if (tracing_disabled)
-                return -ENODEV;
-
-        if (trace_array_get(tr) < 0)
-                return -ENODEV;
+        ret = tracing_check_open_get_tr(tr);
+        if (ret)
+                return ret;
 
         ret = seq_open(file, &show_traces_seq_ops);
         if (ret) {
@@ -4710,11 +4722,9 @@ static int tracing_trace_options_open(struct inode *inode, struct file *file)
         struct trace_array *tr = inode->i_private;
         int ret;
 
-        if (tracing_disabled)
-                return -ENODEV;
-
-        if (trace_array_get(tr) < 0)
-                return -ENODEV;
+        ret = tracing_check_open_get_tr(tr);
+        if (ret)
+                return ret;
 
         ret = single_open(file, tracing_trace_options_show, inode->i_private);
         if (ret < 0)
@@ -5051,8 +5061,11 @@ static const struct seq_operations tracing_saved_tgids_seq_ops = {
 
 static int tracing_saved_tgids_open(struct inode *inode, struct file *filp)
 {
-        if (tracing_disabled)
-                return -ENODEV;
+        int ret;
+
+        ret = tracing_check_open_get_tr(NULL);
+        if (ret)
+                return ret;
 
         return seq_open(filp, &tracing_saved_tgids_seq_ops);
 }
@@ -5128,8 +5141,11 @@ static const struct seq_operations tracing_saved_cmdlines_seq_ops = {
 
 static int tracing_saved_cmdlines_open(struct inode *inode, struct file *filp)
 {
-        if (tracing_disabled)
-                return -ENODEV;
+        int ret;
+
+        ret = tracing_check_open_get_tr(NULL);
+        if (ret)
+                return ret;
 
         return seq_open(filp, &tracing_saved_cmdlines_seq_ops);
 }
@@ -5293,8 +5309,11 @@ static const struct seq_operations tracing_eval_map_seq_ops = {
 
 static int tracing_eval_map_open(struct inode *inode, struct file *filp)
 {
-        if (tracing_disabled)
-                return -ENODEV;
+        int ret;
+
+        ret = tracing_check_open_get_tr(NULL);
+        if (ret)
+                return ret;
 
         return seq_open(filp, &tracing_eval_map_seq_ops);
 }
@@ -5817,13 +5836,11 @@ static int tracing_open_pipe(struct inode *inode, struct file *filp)
 {
         struct trace_array *tr = inode->i_private;
         struct trace_iterator *iter;
-        int ret = 0;
-
-        if (tracing_disabled)
-                return -ENODEV;
+        int ret;
 
-        if (trace_array_get(tr) < 0)
-                return -ENODEV;
+        ret = tracing_check_open_get_tr(tr);
+        if (ret)
+                return ret;
 
         mutex_lock(&trace_types_lock);
 
@@ -6560,11 +6577,9 @@ static int tracing_clock_open(struct inode *inode, struct file *file)
         struct trace_array *tr = inode->i_private;
         int ret;
 
-        if (tracing_disabled)
-                return -ENODEV;
-
-        if (trace_array_get(tr))
-                return -ENODEV;
+        ret = tracing_check_open_get_tr(tr);
+        if (ret)
+                return ret;
 
         ret = single_open(file, tracing_clock_show, inode->i_private);
         if (ret < 0)
@@ -6594,11 +6609,9 @@ static int tracing_time_stamp_mode_open(struct inode *inode, struct file *file)
         struct trace_array *tr = inode->i_private;
         int ret;
 
-        if (tracing_disabled)
-                return -ENODEV;
-
-        if (trace_array_get(tr))
-                return -ENODEV;
+        ret = tracing_check_open_get_tr(tr);
+        if (ret)
+                return ret;
 
         ret = single_open(file, tracing_time_stamp_mode_show, inode->i_private);
         if (ret < 0)
@@ -6651,10 +6664,11 @@ static int tracing_snapshot_open(struct inode *inode, struct file *file)
         struct trace_array *tr = inode->i_private;
         struct trace_iterator *iter;
         struct seq_file *m;
-        int ret = 0;
+        int ret;
 
-        if (trace_array_get(tr) < 0)
-                return -ENODEV;
+        ret = tracing_check_open_get_tr(tr);
+        if (ret)
+                return ret;
 
         if (file->f_mode & FMODE_READ) {
                 iter = __tracing_open(inode, file, true);
@@ -7118,8 +7132,9 @@ static int tracing_err_log_open(struct inode *inode, struct file *file)
         struct trace_array *tr = inode->i_private;
         int ret = 0;
 
-        if (trace_array_get(tr) < 0)
-                return -ENODEV;
+        ret = tracing_check_open_get_tr(tr);
+        if (ret)
+                return ret;
 
         /* If this file was opened for write, then erase contents */
         if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC))
@@ -7170,11 +7185,9 @@ static int tracing_buffers_open(struct inode *inode, struct file *filp)
         struct ftrace_buffer_info *info;
         int ret;
 
-        if (tracing_disabled)
-                return -ENODEV;
-
-        if (trace_array_get(tr) < 0)
-                return -ENODEV;
+        ret = tracing_check_open_get_tr(tr);
+        if (ret)
+                return ret;
 
         info = kzalloc(sizeof(*info), GFP_KERNEL);
         if (!info) {