xref: /linux/drivers/ufs/core/ufs-fault-injection.c (revision 3a39d672e7f48b8d6b91a09afa4b55352773b4b5)
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 
11 static int ufs_fault_get(char *buffer, const struct kernel_param *kp);
12 static int ufs_fault_set(const char *val, const struct kernel_param *kp);
13 
14 static const struct kernel_param_ops ufs_fault_ops = {
15 	.get = ufs_fault_get,
16 	.set = ufs_fault_set,
17 };
18 
19 enum { 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  */
25 static char g_trigger_eh_str[FAULT_INJ_STR_SIZE];
26 module_param_cb(trigger_eh, &ufs_fault_ops, g_trigger_eh_str, 0644);
27 MODULE_PARM_DESC(trigger_eh,
28 	"Fault injection. trigger_eh=<interval>,<probability>,<space>,<times>");
29 static DECLARE_FAULT_ATTR(ufs_trigger_eh_attr);
30 
31 static char g_timeout_str[FAULT_INJ_STR_SIZE];
32 module_param_cb(timeout, &ufs_fault_ops, g_timeout_str, 0644);
33 MODULE_PARM_DESC(timeout,
34 	"Fault injection. timeout=<interval>,<probability>,<space>,<times>");
35 static DECLARE_FAULT_ATTR(ufs_timeout_attr);
36 
ufs_fault_get(char * buffer,const struct kernel_param * kp)37 static 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 
ufs_fault_set(const char * val,const struct kernel_param * kp)44 static 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 
ufs_fault_inject_hba_init(struct ufs_hba * hba)64 void 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 
ufs_trigger_eh(struct ufs_hba * hba)74 bool ufs_trigger_eh(struct ufs_hba *hba)
75 {
76 	return should_fail(&hba->trigger_eh_attr, 1);
77 }
78 
ufs_fail_completion(struct ufs_hba * hba)79 bool ufs_fail_completion(struct ufs_hba *hba)
80 {
81 	return should_fail(&hba->timeout_attr, 1);
82 }
83