fs/nfsd/fault_inject.c

   1 /*
   2  * Copyright (c) 2011 Bryan Schumaker <bjschuma@netapp.com>
   3  *
   4  * Uses debugfs to create fault injection points for client testing
   5  */
   6
   7 #include <linux/types.h>
   8 #include <linux/fs.h>
   9 #include <linux/debugfs.h>
  10 #include <linux/module.h>
  11
  12 #include "state.h"
  13
  14 struct nfsd_fault_inject_op {
  15         char *file;
  16         void (*func)(u64);
  17 };
  18
  19 static struct nfsd_fault_inject_op inject_ops[] = {
  20         {
  21                 .file   = "forget_clients",
  22                 .func   = nfsd_forget_clients,
  23         },
  24         {
  25                 .file   = "forget_locks",
  26                 .func   = nfsd_forget_locks,
  27         },
  28         {
  29                 .file   = "forget_openowners",
  30                 .func   = nfsd_forget_openowners,
  31         },
  32         {
  33                 .file   = "forget_delegations",
  34                 .func   = nfsd_forget_delegations,
  35         },
  36         {
  37                 .file   = "recall_delegations",
  38                 .func   = nfsd_recall_delegations,
  39         },
  40 };
  41
  42 static long int NUM_INJECT_OPS = sizeof(inject_ops) / sizeof(struct nfsd_fault_inject_op);
  43 static struct dentry *debug_dir;
  44
  45 static int nfsd_inject_set(void *op_ptr, u64 val)
  46 {
  47         struct nfsd_fault_inject_op *op = op_ptr;
  48
  49         if (val == 0)
  50                 printk(KERN_INFO "NFSD Fault Injection: %s (all)", op->file);
  51         else
  52                 printk(KERN_INFO "NFSD Fault Injection: %s (n = %llu)", op->file, val);
  53
  54         op->func(val);
  55         return 0;
  56 }
  57
  58 static int nfsd_inject_get(void *data, u64 *val)
  59 {
  60         *val = 0;
  61         return 0;
  62 }
  63
  64 DEFINE_SIMPLE_ATTRIBUTE(fops_nfsd, nfsd_inject_get, nfsd_inject_set, "%llu\n");
  65
  66 void nfsd_fault_inject_cleanup(void)
  67 {
  68         debugfs_remove_recursive(debug_dir);
  69 }
  70
  71 int nfsd_fault_inject_init(void)
  72 {
  73         unsigned int i;
  74         struct nfsd_fault_inject_op *op;
  75         umode_t mode = S_IFREG | S_IRUSR | S_IWUSR;
  76
  77         debug_dir = debugfs_create_dir("nfsd", NULL);
  78         if (!debug_dir)
  79                 goto fail;
  80
  81         for (i = 0; i < NUM_INJECT_OPS; i++) {
  82                 op = &inject_ops[i];
  83                 if (!debugfs_create_file(op->file, mode, debug_dir, op, &fops_nfsd))
  84                         goto fail;
  85         }
  86         return 0;
  87
  88 fail:
  89         nfsd_fault_inject_cleanup();
  90         return -ENOMEM;
  91 }