/* -*- mode: c; c-basic-offset: 8; -*-
   * vim: noexpandtab sw=8 ts=8 sts=0:
   *
   * netdebug.c
   *
   * debug functionality for o2net
   *
   * Copyright (C) 2005, 2008 Oracle.  All rights reserved.
   *
   * This program 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 of the License, or (at your option) any later version.
   *
   * This program 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 this program; if not, write to the
   * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
   * Boston, MA 021110-1307, USA.
   *
   */
  
  #ifdef CONFIG_DEBUG_FS
  
  #include <linux/module.h>
  #include <linux/types.h>
  #include <linux/slab.h>
  #include <linux/idr.h>
  #include <linux/kref.h>
  #include <linux/seq_file.h>
  #include <linux/debugfs.h>
  
  #include <linux/uaccess.h>
  
  #include "tcp.h"
  #include "nodemanager.h"
  #define MLOG_MASK_PREFIX ML_TCP
  #include "masklog.h"
  
  #include "tcp_internal.h"
  
  #define O2NET_DEBUG_DIR		"o2net"
  #define SC_DEBUG_NAME		"sock_containers"
  #define NST_DEBUG_NAME		"send_tracking"
  
  static struct dentry *o2net_dentry;
  static struct dentry *sc_dentry;
  static struct dentry *nst_dentry;
  
  static DEFINE_SPINLOCK(o2net_debug_lock);
  
  static LIST_HEAD(sock_containers);
  static LIST_HEAD(send_tracking);
  
  void o2net_debug_add_nst(struct o2net_send_tracking *nst)
  {
  	spin_lock(&o2net_debug_lock);
  	list_add(&nst->st_net_debug_item, &send_tracking);
  	spin_unlock(&o2net_debug_lock);
  }
  
  void o2net_debug_del_nst(struct o2net_send_tracking *nst)
  {
  	spin_lock(&o2net_debug_lock);
  	if (!list_empty(&nst->st_net_debug_item))
  		list_del_init(&nst->st_net_debug_item);
  	spin_unlock(&o2net_debug_lock);
  }
  
  static struct o2net_send_tracking
  			*next_nst(struct o2net_send_tracking *nst_start)
  {
  	struct o2net_send_tracking *nst, *ret = NULL;
  
  	assert_spin_locked(&o2net_debug_lock);
  
  	list_for_each_entry(nst, &nst_start->st_net_debug_item,
  			    st_net_debug_item) {
  		/* discover the head of the list */
  		if (&nst->st_net_debug_item == &send_tracking)
  			break;
  
  		/* use st_task to detect real nsts in the list */
  		if (nst->st_task != NULL) {
  			ret = nst;
  			break;
  		}
  	}
  
  	return ret;
  }
  
  static void *nst_seq_start(struct seq_file *seq, loff_t *pos)
  {
  	struct o2net_send_tracking *nst, *dummy_nst = seq->private;
  
  	spin_lock(&o2net_debug_lock);
  	nst = next_nst(dummy_nst);
  	spin_unlock(&o2net_debug_lock);
  
  	return nst;
  }
  
  static void *nst_seq_next(struct seq_file *seq, void *v, loff_t *pos)
  {
  	struct o2net_send_tracking *nst, *dummy_nst = seq->private;
  
  	spin_lock(&o2net_debug_lock);
  	nst = next_nst(dummy_nst);
  	list_del_init(&dummy_nst->st_net_debug_item);
  	if (nst)
  		list_add(&dummy_nst->st_net_debug_item,
  			 &nst->st_net_debug_item);
  	spin_unlock(&o2net_debug_lock);
  
  	return nst; /* unused, just needs to be null when done */
  }
  
  static int nst_seq_show(struct seq_file *seq, void *v)
  {
  	struct o2net_send_tracking *nst, *dummy_nst = seq->private;
  
  	spin_lock(&o2net_debug_lock);
  	nst = next_nst(dummy_nst);
  
  	if (nst != NULL) {
  		/* get_task_comm isn't exported.  oh well. */
  		seq_printf(seq, "%p:
  "
  			   "  pid:          %lu
  "
  			   "  tgid:         %lu
  "
  			   "  process name: %s
  "
  			   "  node:         %u
  "
  			   "  sc:           %p
  "
  			   "  message id:   %d
  "
  			   "  message type: %u
  "
  			   "  message key:  0x%08x
  "

  			   "  sock acquiry: %lu.%ld
  "
  			   "  send start:   %lu.%ld
  "
  			   "  wait start:   %lu.%ld
  ",

  			   nst, (unsigned long)nst->st_task->pid,
  			   (unsigned long)nst->st_task->tgid,
  			   nst->st_task->comm, nst->st_node,
  			   nst->st_sc, nst->st_id, nst->st_msg_type,
  			   nst->st_msg_key,

  			   nst->st_sock_time.tv_sec,

  			   (long)nst->st_sock_time.tv_usec,

  			   nst->st_send_time.tv_sec,

  			   (long)nst->st_send_time.tv_usec,

  			   nst->st_status_time.tv_sec,

  			   (long)nst->st_status_time.tv_usec);

  	}
  
  	spin_unlock(&o2net_debug_lock);
  
  	return 0;
  }
  
  static void nst_seq_stop(struct seq_file *seq, void *v)
  {
  }
  
  static struct seq_operations nst_seq_ops = {
  	.start = nst_seq_start,
  	.next = nst_seq_next,
  	.stop = nst_seq_stop,
  	.show = nst_seq_show,
  };
  
  static int nst_fop_open(struct inode *inode, struct file *file)
  {
  	struct o2net_send_tracking *dummy_nst;
  	struct seq_file *seq;
  	int ret;
  
  	dummy_nst = kmalloc(sizeof(struct o2net_send_tracking), GFP_KERNEL);
  	if (dummy_nst == NULL) {
  		ret = -ENOMEM;
  		goto out;
  	}
  	dummy_nst->st_task = NULL;
  
  	ret = seq_open(file, &nst_seq_ops);
  	if (ret)
  		goto out;
  
  	seq = file->private_data;
  	seq->private = dummy_nst;
  	o2net_debug_add_nst(dummy_nst);
  
  	dummy_nst = NULL;
  
  out:
  	kfree(dummy_nst);
  	return ret;
  }
  
  static int nst_fop_release(struct inode *inode, struct file *file)
  {
  	struct seq_file *seq = file->private_data;
  	struct o2net_send_tracking *dummy_nst = seq->private;
  
  	o2net_debug_del_nst(dummy_nst);
  	return seq_release_private(inode, file);
  }
  
  static struct file_operations nst_seq_fops = {
  	.open = nst_fop_open,
  	.read = seq_read,
  	.llseek = seq_lseek,
  	.release = nst_fop_release,
  };
  
  void o2net_debug_add_sc(struct o2net_sock_container *sc)
  {
  	spin_lock(&o2net_debug_lock);
  	list_add(&sc->sc_net_debug_item, &sock_containers);
  	spin_unlock(&o2net_debug_lock);
  }
  
  void o2net_debug_del_sc(struct o2net_sock_container *sc)
  {
  	spin_lock(&o2net_debug_lock);
  	list_del_init(&sc->sc_net_debug_item);
  	spin_unlock(&o2net_debug_lock);
  }
  
  static struct o2net_sock_container
  			*next_sc(struct o2net_sock_container *sc_start)
  {
  	struct o2net_sock_container *sc, *ret = NULL;
  
  	assert_spin_locked(&o2net_debug_lock);
  
  	list_for_each_entry(sc, &sc_start->sc_net_debug_item,
  			    sc_net_debug_item) {
  		/* discover the head of the list miscast as a sc */
  		if (&sc->sc_net_debug_item == &sock_containers)
  			break;
  
  		/* use sc_page to detect real scs in the list */
  		if (sc->sc_page != NULL) {
  			ret = sc;
  			break;
  		}
  	}
  
  	return ret;
  }
  
  static void *sc_seq_start(struct seq_file *seq, loff_t *pos)
  {
  	struct o2net_sock_container *sc, *dummy_sc = seq->private;
  
  	spin_lock(&o2net_debug_lock);
  	sc = next_sc(dummy_sc);
  	spin_unlock(&o2net_debug_lock);
  
  	return sc;
  }
  
  static void *sc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
  {
  	struct o2net_sock_container *sc, *dummy_sc = seq->private;
  
  	spin_lock(&o2net_debug_lock);
  	sc = next_sc(dummy_sc);
  	list_del_init(&dummy_sc->sc_net_debug_item);
  	if (sc)
  		list_add(&dummy_sc->sc_net_debug_item, &sc->sc_net_debug_item);
  	spin_unlock(&o2net_debug_lock);
  
  	return sc; /* unused, just needs to be null when done */
  }

  #define TV_SEC_USEC(TV) TV.tv_sec, (long)TV.tv_usec

  
  static int sc_seq_show(struct seq_file *seq, void *v)
  {
  	struct o2net_sock_container *sc, *dummy_sc = seq->private;
  
  	spin_lock(&o2net_debug_lock);
  	sc = next_sc(dummy_sc);
  
  	if (sc != NULL) {
  		struct inet_sock *inet = NULL;
  
  		__be32 saddr = 0, daddr = 0;
  		__be16 sport = 0, dport = 0;
  
  		if (sc->sc_sock) {
  			inet = inet_sk(sc->sc_sock->sk);
  			/* the stack's structs aren't sparse endian clean */
  			saddr = (__force __be32)inet->saddr;
  			daddr = (__force __be32)inet->daddr;
  			sport = (__force __be16)inet->sport;
  			dport = (__force __be16)inet->dport;
  		}
  
  		/* XXX sigh, inet-> doesn't have sparse annotation so any
  		 * use of it here generates a warning with -Wbitwise */
  		seq_printf(seq, "%p:
  "
  			   "  krefs:           %d
  "

  			   "  sock:            %pI4:%u -> "
  					      "%pI4:%u
  "

  			   "  remote node:     %s
  "
  			   "  page off:        %zu
  "
  			   "  handshake ok:    %u
  "

  			   "  timer:           %lu.%ld
  "
  			   "  data ready:      %lu.%ld
  "
  			   "  advance start:   %lu.%ld
  "
  			   "  advance stop:    %lu.%ld
  "
  			   "  func start:      %lu.%ld
  "
  			   "  func stop:       %lu.%ld
  "

  			   "  func key:        %u
  "
  			   "  func type:       %u
  ",
  			   sc,
  			   atomic_read(&sc->sc_kref.refcount),

  			   &saddr, inet ? ntohs(sport) : 0,
  			   &daddr, inet ? ntohs(dport) : 0,

  			   sc->sc_node->nd_name,
  			   sc->sc_page_off,
  			   sc->sc_handshake_ok,
  			   TV_SEC_USEC(sc->sc_tv_timer),
  			   TV_SEC_USEC(sc->sc_tv_data_ready),
  			   TV_SEC_USEC(sc->sc_tv_advance_start),
  			   TV_SEC_USEC(sc->sc_tv_advance_stop),
  			   TV_SEC_USEC(sc->sc_tv_func_start),
  			   TV_SEC_USEC(sc->sc_tv_func_stop),
  			   sc->sc_msg_key,
  			   sc->sc_msg_type);
  	}
  
  
  	spin_unlock(&o2net_debug_lock);
  
  	return 0;
  }
  
  static void sc_seq_stop(struct seq_file *seq, void *v)
  {
  }
  
  static struct seq_operations sc_seq_ops = {
  	.start = sc_seq_start,
  	.next = sc_seq_next,
  	.stop = sc_seq_stop,
  	.show = sc_seq_show,
  };
  
  static int sc_fop_open(struct inode *inode, struct file *file)
  {
  	struct o2net_sock_container *dummy_sc;
  	struct seq_file *seq;
  	int ret;
  
  	dummy_sc = kmalloc(sizeof(struct o2net_sock_container), GFP_KERNEL);
  	if (dummy_sc == NULL) {
  		ret = -ENOMEM;
  		goto out;
  	}
  	dummy_sc->sc_page = NULL;
  
  	ret = seq_open(file, &sc_seq_ops);
  	if (ret)
  		goto out;
  
  	seq = file->private_data;
  	seq->private = dummy_sc;
  	o2net_debug_add_sc(dummy_sc);
  
  	dummy_sc = NULL;
  
  out:
  	kfree(dummy_sc);
  	return ret;
  }
  
  static int sc_fop_release(struct inode *inode, struct file *file)
  {
  	struct seq_file *seq = file->private_data;
  	struct o2net_sock_container *dummy_sc = seq->private;
  
  	o2net_debug_del_sc(dummy_sc);
  	return seq_release_private(inode, file);
  }
  
  static struct file_operations sc_seq_fops = {
  	.open = sc_fop_open,
  	.read = seq_read,
  	.llseek = seq_lseek,
  	.release = sc_fop_release,
  };
  
  int o2net_debugfs_init(void)
  {
  	o2net_dentry = debugfs_create_dir(O2NET_DEBUG_DIR, NULL);
  	if (!o2net_dentry) {
  		mlog_errno(-ENOMEM);
  		goto bail;
  	}
  
  	nst_dentry = debugfs_create_file(NST_DEBUG_NAME, S_IFREG|S_IRUSR,
  					 o2net_dentry, NULL,
  					 &nst_seq_fops);
  	if (!nst_dentry) {
  		mlog_errno(-ENOMEM);
  		goto bail;
  	}
  
  	sc_dentry = debugfs_create_file(SC_DEBUG_NAME, S_IFREG|S_IRUSR,
  					o2net_dentry, NULL,
  					&sc_seq_fops);
  	if (!sc_dentry) {
  		mlog_errno(-ENOMEM);
  		goto bail;
  	}
  
  	return 0;
  bail:
  	if (sc_dentry)
  		debugfs_remove(sc_dentry);
  	if (nst_dentry)
  		debugfs_remove(nst_dentry);
  	if (o2net_dentry)
  		debugfs_remove(o2net_dentry);
  	return -ENOMEM;
  }
  
  void o2net_debugfs_exit(void)
  {
  	if (sc_dentry)
  		debugfs_remove(sc_dentry);
  	if (nst_dentry)
  		debugfs_remove(nst_dentry);
  	if (o2net_dentry)
  		debugfs_remove(o2net_dentry);
  }
  
  #endif	/* CONFIG_DEBUG_FS */