ufs-fault-injection.c

 1// SPDX-License-Identifier: GPL-2.0-or-later
 2
 3#include <linux/kconfig.h>
 4#include <linux/types.h>
 5#include <linux/fault-inject.h>
 6#include <linux/debugfs.h>
 7#include <linux/module.h>
 8#include <ufs/ufshcd.h>
 9#include "ufs-fault-injection.h"
10
11static int ufs_fault_get(char *buffer, const struct kernel_param *kp);
12static int ufs_fault_set(const char *val, const struct kernel_param *kp);
13
14static const struct kernel_param_ops ufs_fault_ops = {
15	.get = ufs_fault_get,
16	.set = ufs_fault_set,
17};
18
19enum { FAULT_INJ_STR_SIZE = 80 };
20
21/*
22 * For more details about fault injection, please refer to
23 * Documentation/fault-injection/fault-injection.rst.
24 */
25static char g_trigger_eh_str[FAULT_INJ_STR_SIZE];
26module_param_cb(trigger_eh, &ufs_fault_ops, g_trigger_eh_str, 0644);
27MODULE_PARM_DESC(trigger_eh,
28	"Fault injection. trigger_eh=<interval>,<probability>,<space>,<times>");
29static DECLARE_FAULT_ATTR(ufs_trigger_eh_attr);
30
31static char g_timeout_str[FAULT_INJ_STR_SIZE];
32module_param_cb(timeout, &ufs_fault_ops, g_timeout_str, 0644);
33MODULE_PARM_DESC(timeout,
34	"Fault injection. timeout=<interval>,<probability>,<space>,<times>");
35static DECLARE_FAULT_ATTR(ufs_timeout_attr);
36
37static int ufs_fault_get(char *buffer, const struct kernel_param *kp)
38{
39	const char *fault_str = kp->arg;
40
41	return sysfs_emit(buffer, "%s\n", fault_str);
42}
43
44static int ufs_fault_set(const char *val, const struct kernel_param *kp)
45{
46	struct fault_attr *attr = NULL;
47
48	if (kp->arg == g_trigger_eh_str)
49		attr = &ufs_trigger_eh_attr;
50	else if (kp->arg == g_timeout_str)
51		attr = &ufs_timeout_attr;
52
53	if (WARN_ON_ONCE(!attr))
54		return -EINVAL;
55
56	if (!setup_fault_attr(attr, (char *)val))
57		return -EINVAL;
58
59	strscpy(kp->arg, val, FAULT_INJ_STR_SIZE);
60
61	return 0;
62}
63
64void ufs_fault_inject_hba_init(struct ufs_hba *hba)
65{
66	hba->trigger_eh_attr = ufs_trigger_eh_attr;
67	hba->timeout_attr = ufs_timeout_attr;
68#ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
69	fault_create_debugfs_attr("trigger_eh_inject", hba->debugfs_root, &hba->trigger_eh_attr);
70	fault_create_debugfs_attr("timeout_inject", hba->debugfs_root, &hba->timeout_attr);
71#endif
72}
73
74bool ufs_trigger_eh(struct ufs_hba *hba)
75{
76	return should_fail(&hba->trigger_eh_attr, 1);
77}
78
79bool ufs_fail_completion(struct ufs_hba *hba)
80{
81	return should_fail(&hba->timeout_attr, 1);
82}