/* SCTP kernel implementation
   * (C) Copyright IBM Corp. 2001, 2004
   *
   * This file is part of the SCTP kernel implementation
   *
   * Support for memory object debugging.  This allows one to monitor the
   * object allocations/deallocations for types instrumented for this
   * via the proc fs.
   *
   * This SCTP implementation is free software;
   * you can redistribute it and/or modify it under the terms of
   * the GNU General Public License as published by
   * the Free Software Foundation; either version 2, or (at your option)
   * any later version.
   *
   * This SCTP implementation is distributed in the hope that it
   * will be useful, but WITHOUT ANY WARRANTY; without even the implied
   *                 ************************
   * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
   * See the GNU General Public License for more details.
   *
   * You should have received a copy of the GNU General Public License
   * along with GNU CC; see the file COPYING.  If not, see
   * <http://www.gnu.org/licenses/>.
   *
   * Please send any bug reports or fixes you make to the
   * email address(es):
   *    lksctp developers <linux-sctp@vger.kernel.org>
   *
   * Written or modified by:
   *    Jon Grimm             <jgrimm@us.ibm.com>
   */
  
  #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  
  #include <linux/kernel.h>
  #include <net/sctp/sctp.h>
  
  /*
   * Global counters to count raw object allocation counts.
   * To add new counters, choose a unique suffix for the variable
   * name as the helper macros key off this suffix to make
   * life easier for the programmer.
   */
  
  SCTP_DBG_OBJCNT(sock);
  SCTP_DBG_OBJCNT(ep);
  SCTP_DBG_OBJCNT(transport);
  SCTP_DBG_OBJCNT(assoc);
  SCTP_DBG_OBJCNT(bind_addr);
  SCTP_DBG_OBJCNT(bind_bucket);
  SCTP_DBG_OBJCNT(chunk);
  SCTP_DBG_OBJCNT(addr);
  SCTP_DBG_OBJCNT(ssnmap);
  SCTP_DBG_OBJCNT(datamsg);
  SCTP_DBG_OBJCNT(keys);
  
  /* An array to make it easy to pretty print the debug information
   * to the proc fs.
   */
  static sctp_dbg_objcnt_entry_t sctp_dbg_objcnt[] = {
  	SCTP_DBG_OBJCNT_ENTRY(sock),
  	SCTP_DBG_OBJCNT_ENTRY(ep),
  	SCTP_DBG_OBJCNT_ENTRY(assoc),
  	SCTP_DBG_OBJCNT_ENTRY(transport),
  	SCTP_DBG_OBJCNT_ENTRY(chunk),
  	SCTP_DBG_OBJCNT_ENTRY(bind_addr),
  	SCTP_DBG_OBJCNT_ENTRY(bind_bucket),
  	SCTP_DBG_OBJCNT_ENTRY(addr),
  	SCTP_DBG_OBJCNT_ENTRY(ssnmap),
  	SCTP_DBG_OBJCNT_ENTRY(datamsg),
  	SCTP_DBG_OBJCNT_ENTRY(keys),
  };
  
  /* Callback from procfs to read out objcount information.
   * Walk through the entries in the sctp_dbg_objcnt array, dumping
   * the raw object counts for each monitored type.
   */
  static int sctp_objcnt_seq_show(struct seq_file *seq, void *v)
  {
  	int i;
  
  	i = (int)*(loff_t *)v;
  	seq_setwidth(seq, 127);
  	seq_printf(seq, "%s: %d", sctp_dbg_objcnt[i].label,
  				atomic_read(sctp_dbg_objcnt[i].counter));
  	seq_pad(seq, '
  ');
  	return 0;
  }
  
  static void *sctp_objcnt_seq_start(struct seq_file *seq, loff_t *pos)
  {
  	return (*pos >= ARRAY_SIZE(sctp_dbg_objcnt)) ? NULL : (void *)pos;
  }
  
  static void sctp_objcnt_seq_stop(struct seq_file *seq, void *v)
  {
  }
  
  static void *sctp_objcnt_seq_next(struct seq_file *seq, void *v, loff_t *pos)
  {
  	++*pos;
  	return (*pos >= ARRAY_SIZE(sctp_dbg_objcnt)) ? NULL : (void *)pos;
  }
  
  static const struct seq_operations sctp_objcnt_seq_ops = {
  	.start = sctp_objcnt_seq_start,
  	.next  = sctp_objcnt_seq_next,
  	.stop  = sctp_objcnt_seq_stop,
  	.show  = sctp_objcnt_seq_show,
  };
  
  static int sctp_objcnt_seq_open(struct inode *inode, struct file *file)
  {
  	return seq_open(file, &sctp_objcnt_seq_ops);
  }
  
  static const struct file_operations sctp_objcnt_ops = {
  	.open	 = sctp_objcnt_seq_open,
  	.read	 = seq_read,
  	.llseek	 = seq_lseek,
  	.release = seq_release,
  };
  
  /* Initialize the objcount in the proc filesystem.  */
  void sctp_dbg_objcnt_init(struct net *net)
  {
  	struct proc_dir_entry *ent;
  
  	ent = proc_create("sctp_dbg_objcnt", 0,
  			  net->sctp.proc_net_sctp, &sctp_objcnt_ops);
  	if (!ent)
  		pr_warn("sctp_dbg_objcnt: Unable to create /proc entry.
  ");
  }
  
  /* Cleanup the objcount entry in the proc filesystem.  */
  void sctp_dbg_objcnt_exit(struct net *net)
  {
  	remove_proc_entry("sctp_dbg_objcnt", net->sctp.proc_net_sctp);
  }