module/spl/spl-err.c

   1 /*****************************************************************************\
   2  *  Copyright (C) 2007-2010 Lawrence Livermore National Security, LLC.
   3  *  Copyright (C) 2007 The Regents of the University of California.
   4  *  Produced at Lawrence Livermore National Laboratory (cf, DISCLAIMER).
   5  *  Written by Brian Behlendorf <behlendorf1@llnl.gov>.
   6  *  UCRL-CODE-235197
   7  *
   8  *  This file is part of the SPL, Solaris Porting Layer.
   9  *  For details, see <http://zfsonlinux.org/>.
  10  *
  11  *  The SPL is free software; you can redistribute it and/or modify it
  12  *  under the terms of the GNU General Public License as published by the
  13  *  Free Software Foundation; either version 2 of the License, or (at your
  14  *  option) any later version.
  15  *
  16  *  The SPL is distributed in the hope that it will be useful, but WITHOUT
  17  *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  18  *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  19  *  for more details.
  20  *
  21  *  You should have received a copy of the GNU General Public License along
  22  *  with the SPL.  If not, see <http://www.gnu.org/licenses/>.
  23  *****************************************************************************
  24  *  Solaris Porting Layer (SPL) Error Implementation.
  25 \*****************************************************************************/
  26
  27 #include <sys/sysmacros.h>
  28 #include <sys/cmn_err.h>
  29 #include <linux/ratelimit.h>
  30
  31 /*
  32  * Limit the number of stack traces dumped to not more than 5 every
  33  * 60 seconds to prevent denial-of-service attacks from debug code.
  34  */
  35 DEFINE_RATELIMIT_STATE(dumpstack_ratelimit_state, 60 * HZ, 5);
  36
  37 void
  38 spl_dumpstack(void)
  39 {
  40         if (__ratelimit(&dumpstack_ratelimit_state)) {
  41                 printk("Showing stack for process %d\n", current->pid);
  42                 dump_stack();
  43         }
  44 }
  45 EXPORT_SYMBOL(spl_dumpstack);
  46
  47 int
  48 spl_panic(const char *file, const char *func, int line, const char *fmt, ...) {
  49         const char *newfile;
  50         char msg[MAXMSGLEN];
  51         va_list ap;
  52
  53         newfile = strrchr(file, '/');
  54         if (newfile != NULL)
  55                 newfile = newfile + 1;
  56         else
  57                 newfile = file;
  58
  59         va_start(ap, fmt);
  60         (void) vsnprintf(msg, sizeof (msg), fmt, ap);
  61         va_end(ap);
  62
  63         printk(KERN_EMERG "%s", msg);
  64         printk(KERN_EMERG "PANIC at %s:%d:%s()\n", newfile, line, func);
  65         spl_dumpstack();
  66
  67         /* Halt the thread to facilitate further debugging */
  68         set_current_state(TASK_UNINTERRUPTIBLE);
  69         while (1)
  70                 schedule();
  71
  72         /* Unreachable */
  73         return (1);
  74 }
  75 EXPORT_SYMBOL(spl_panic);
  76
  77 void
  78 vcmn_err(int ce, const char *fmt, va_list ap)
  79 {
  80         char msg[MAXMSGLEN];
  81
  82         vsnprintf(msg, MAXMSGLEN - 1, fmt, ap);
  83
  84         switch (ce) {
  85         case CE_IGNORE:
  86                 break;
  87         case CE_CONT:
  88                 printk("%s", msg);
  89                 break;
  90         case CE_NOTE:
  91                 printk(KERN_NOTICE "NOTICE: %s\n", msg);
  92                 break;
  93         case CE_WARN:
  94                 printk(KERN_WARNING "WARNING: %s\n", msg);
  95                 break;
  96         case CE_PANIC:
  97                 printk(KERN_EMERG "PANIC: %s\n", msg);
  98                 spl_dumpstack();
  99
 100                 /* Halt the thread to facilitate further debugging */
 101                 set_current_state(TASK_UNINTERRUPTIBLE);
 102                 while (1)
 103                         schedule();
 104         }
 105 } /* vcmn_err() */
 106 EXPORT_SYMBOL(vcmn_err);
 107
 108 void
 109 cmn_err(int ce, const char *fmt, ...)
 110 {
 111         va_list ap;
 112
 113         va_start(ap, fmt);
 114         vcmn_err(ce, fmt, ap);
 115         va_end(ap);
 116 } /* cmn_err() */
 117 EXPORT_SYMBOL(cmn_err);