drivers/ufs/core/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
  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
  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
  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
  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
  74 bool ufs_trigger_eh(struct ufs_hba *hba)
  75 {
  76         return should_fail(&hba->trigger_eh_attr, 1);
  77 }
  78
  79 bool ufs_fail_completion(struct ufs_hba *hba)
  80 {
  81         return should_fail(&hba->timeout_attr, 1);
  82 }