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         u64 (*forget)(struct nfs4_client *, u64);
  17         u64 (*print)(struct nfs4_client *, u64);
  18 };
  19
  20 static struct nfsd_fault_inject_op inject_ops[] = {
  21         {
  22                 .file   = "forget_clients",
  23                 .forget = nfsd_forget_client,
  24                 .print  = nfsd_print_client,
  25         },
  26         {
  27                 .file   = "forget_locks",
  28                 .forget = nfsd_forget_client_locks,
  29                 .print  = nfsd_print_client_locks,
  30         },
  31         {
  32                 .file   = "forget_openowners",
  33                 .forget = nfsd_forget_client_openowners,
  34                 .print  = nfsd_print_client_openowners,
  35         },
  36         {
  37                 .file   = "forget_delegations",
  38                 .forget = nfsd_forget_client_delegations,
  39                 .print  = nfsd_print_client_delegations,
  40         },
  41         {
  42                 .file   = "recall_delegations",
  43                 .forget = nfsd_recall_client_delegations,
  44                 .print  = nfsd_print_client_delegations,
  45         },
  46 };
  47
  48 static long int NUM_INJECT_OPS = sizeof(inject_ops) / sizeof(struct nfsd_fault_inject_op);
  49 static struct dentry *debug_dir;
  50
  51 static int nfsd_inject_set(void *op_ptr, u64 val)
  52 {
  53         u64 count = 0;
  54         struct nfsd_fault_inject_op *op = op_ptr;
  55
  56         if (val == 0)
  57                 printk(KERN_INFO "NFSD Fault Injection: %s (all)", op->file);
  58         else
  59                 printk(KERN_INFO "NFSD Fault Injection: %s (n = %llu)", op->file, val);
  60
  61         nfs4_lock_state();
  62         count = nfsd_for_n_state(val, op->forget);
  63         nfs4_unlock_state();
  64         printk(KERN_INFO "NFSD: %s: found %llu", op->file, count);
  65         return 0;
  66 }
  67
  68 static int nfsd_inject_get(void *op_ptr, u64 *val)
  69 {
  70         struct nfsd_fault_inject_op *op = op_ptr;
  71         nfs4_lock_state();
  72         *val = nfsd_for_n_state(0, op->print);
  73         nfs4_unlock_state();
  74         return 0;
  75 }
  76
  77 DEFINE_SIMPLE_ATTRIBUTE(fops_nfsd, nfsd_inject_get, nfsd_inject_set, "%llu\n");
  78
  79 void nfsd_fault_inject_cleanup(void)
  80 {
  81         debugfs_remove_recursive(debug_dir);
  82 }
  83
  84 int nfsd_fault_inject_init(void)
  85 {
  86         unsigned int i;
  87         struct nfsd_fault_inject_op *op;
  88         umode_t mode = S_IFREG | S_IRUSR | S_IWUSR;
  89
  90         debug_dir = debugfs_create_dir("nfsd", NULL);
  91         if (!debug_dir)
  92                 goto fail;
  93
  94         for (i = 0; i < NUM_INJECT_OPS; i++) {
  95                 op = &inject_ops[i];
  96                 if (!debugfs_create_file(op->file, mode, debug_dir, op, &fops_nfsd))
  97                         goto fail;
  98         }
  99         return 0;
 100
 101 fail:
 102         nfsd_fault_inject_cleanup();
 103         return -ENOMEM;
 104 }