xref: /linux/drivers/ras/debugfs.c (revision bfb921b2a9d5d1123d1d10b196a39db629ddef87)
1 // SPDX-License-Identifier: GPL-2.0-only
2 #include <linux/debugfs.h>
3 #include <linux/ras.h>
4 #include "debugfs.h"
5 
6 static struct dentry *ras_debugfs_dir;
7 
8 static atomic_t trace_count = ATOMIC_INIT(0);
9 
10 struct dentry *ras_get_debugfs_root(void)
11 {
12 	return ras_debugfs_dir;
13 }
14 EXPORT_SYMBOL_GPL(ras_get_debugfs_root);
15 
16 int ras_userspace_consumers(void)
17 {
18 	return atomic_read(&trace_count);
19 }
20 EXPORT_SYMBOL_GPL(ras_userspace_consumers);
21 
22 static int trace_show(struct seq_file *m, void *v)
23 {
24 	return 0;
25 }
26 
27 static int trace_open(struct inode *inode, struct file *file)
28 {
29 	atomic_inc(&trace_count);
30 	return single_open(file, trace_show, NULL);
31 }
32 
33 static int trace_release(struct inode *inode, struct file *file)
34 {
35 	atomic_dec(&trace_count);
36 	return single_release(inode, file);
37 }
38 
39 static const struct file_operations trace_fops = {
40 	.open    = trace_open,
41 	.read    = seq_read,
42 	.llseek  = seq_lseek,
43 	.release = trace_release,
44 };
45 
46 int __init ras_add_daemon_trace(void)
47 {
48 	struct dentry *fentry;
49 
50 	if (!ras_debugfs_dir)
51 		return -ENOENT;
52 
53 	fentry = debugfs_create_file("daemon_active", S_IRUSR, ras_debugfs_dir,
54 				     NULL, &trace_fops);
55 	if (IS_ERR(fentry))
56 		return -ENODEV;
57 
58 	return 0;
59 
60 }
61 
62 void __init ras_debugfs_init(void)
63 {
64 	ras_debugfs_dir = debugfs_create_dir("ras", NULL);
65 }
66