/*
   * Copyright (c) 2011 Bryan Schumaker <bjschuma@netapp.com>
   *
   * Uses debugfs to create fault injection points for client testing
   */
  
  #include <linux/types.h>
  #include <linux/fs.h>
  #include <linux/debugfs.h>
  #include <linux/module.h>
  
  #include "state.h"
  #include "fault_inject.h"
  
  struct nfsd_fault_inject_op {
  	char *file;
  	void (*func)(u64);
  };
  
  static struct nfsd_fault_inject_op inject_ops[] = {
  	{
  		.file   = "forget_clients",
  		.func   = nfsd_forget_clients,
  	},
  	{
  		.file   = "forget_locks",
  		.func   = nfsd_forget_locks,
  	},
  	{
  		.file   = "forget_openowners",
  		.func   = nfsd_forget_openowners,
  	},
  	{
  		.file   = "forget_delegations",
  		.func   = nfsd_forget_delegations,
  	},
  	{
  		.file   = "recall_delegations",
  		.func   = nfsd_recall_delegations,
  	},
  };
  
  static long int NUM_INJECT_OPS = sizeof(inject_ops) / sizeof(struct nfsd_fault_inject_op);
  static struct dentry *debug_dir;
  
  static int nfsd_inject_set(void *op_ptr, u64 val)
  {
  	struct nfsd_fault_inject_op *op = op_ptr;
  
  	if (val == 0)
  		printk(KERN_INFO "NFSD Fault Injection: %s (all)", op->file);
  	else
  		printk(KERN_INFO "NFSD Fault Injection: %s (n = %llu)", op->file, val);
  
  	op->func(val);
  	return 0;
  }
  
  static int nfsd_inject_get(void *data, u64 *val)
  {
  	return 0;
  }
  
  DEFINE_SIMPLE_ATTRIBUTE(fops_nfsd, nfsd_inject_get, nfsd_inject_set, "%llu
  ");
  
  void nfsd_fault_inject_cleanup(void)
  {
  	debugfs_remove_recursive(debug_dir);
  }
  
  int nfsd_fault_inject_init(void)
  {
  	unsigned int i;
  	struct nfsd_fault_inject_op *op;
  	mode_t mode = S_IFREG | S_IRUSR | S_IWUSR;
  
  	debug_dir = debugfs_create_dir("nfsd", NULL);
  	if (!debug_dir)
  		goto fail;
  
  	for (i = 0; i < NUM_INJECT_OPS; i++) {
  		op = &inject_ops[i];
  		if (!debugfs_create_file(op->file, mode, debug_dir, op, &fops_nfsd))
  			goto fail;
  	}
  	return 0;
  
  fail:
  	nfsd_fault_inject_cleanup();
  	return -ENOMEM;
  }