drivers/scsi/ufs/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/module.h>
   7 #include "ufs-fault-injection.h"
   8
   9 static int ufs_fault_get(char *buffer, const struct kernel_param *kp);
  10 static int ufs_fault_set(const char *val, const struct kernel_param *kp);
  11
  12 static const struct kernel_param_ops ufs_fault_ops = {
  13         .get = ufs_fault_get,
  14         .set = ufs_fault_set,
  15 };
  16
  17 enum { FAULT_INJ_STR_SIZE = 80 };
  18
  19 /*
  20  * For more details about fault injection, please refer to
  21  * Documentation/fault-injection/fault-injection.rst.
  22  */
  23 static char g_trigger_eh_str[FAULT_INJ_STR_SIZE];
  24 module_param_cb(trigger_eh, &ufs_fault_ops, g_trigger_eh_str, 0644);
  25 MODULE_PARM_DESC(trigger_eh,
  26         "Fault injection. trigger_eh=<interval>,<probability>,<space>,<times>");
  27 static DECLARE_FAULT_ATTR(ufs_trigger_eh_attr);
  28
  29 static char g_timeout_str[FAULT_INJ_STR_SIZE];
  30 module_param_cb(timeout, &ufs_fault_ops, g_timeout_str, 0644);
  31 MODULE_PARM_DESC(timeout,
  32         "Fault injection. timeout=<interval>,<probability>,<space>,<times>");
  33 static DECLARE_FAULT_ATTR(ufs_timeout_attr);
  34
  35 static int ufs_fault_get(char *buffer, const struct kernel_param *kp)
  36 {
  37         const char *fault_str = kp->arg;
  38
  39         return sysfs_emit(buffer, "%s\n", fault_str);
  40 }
  41
  42 static int ufs_fault_set(const char *val, const struct kernel_param *kp)
  43 {
  44         struct fault_attr *attr = NULL;
  45
  46         if (kp->arg == g_trigger_eh_str)
  47                 attr = &ufs_trigger_eh_attr;
  48         else if (kp->arg == g_timeout_str)
  49                 attr = &ufs_timeout_attr;
  50
  51         if (WARN_ON_ONCE(!attr))
  52                 return -EINVAL;
  53
  54         if (!setup_fault_attr(attr, (char *)val))
  55                 return -EINVAL;
  56
  57         strlcpy(kp->arg, val, FAULT_INJ_STR_SIZE);
  58
  59         return 0;
  60 }
  61
  62 bool ufs_trigger_eh(void)
  63 {
  64         return should_fail(&ufs_trigger_eh_attr, 1);
  65 }
  66
  67 bool ufs_fail_completion(void)
  68 {
  69         return should_fail(&ufs_timeout_attr, 1);
  70 }