text: // SPDX-License-Identifier: GPL-2.0-or-later
  /* -*- 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.
   */
  
  #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"
  #define STATS_DEBUG_NAME	"stats"
  #define NODES_DEBUG_NAME	"connected_nodes"
  
  #define SHOW_SOCK_CONTAINERS	0
  #define SHOW_SOCK_STATS		1
  
  static struct dentry *o2net_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;
  	ktime_t now;
  	s64 sock, send, status;
  
  	spin_lock(&o2net_debug_lock);
  	nst = next_nst(dummy_nst);
  	if (!nst)
  		goto out;
  
  	now = ktime_get();
  	sock = ktime_to_us(ktime_sub(now, nst->st_sock_time));
  	send = ktime_to_us(ktime_sub(now, nst->st_send_time));
  	status = ktime_to_us(ktime_sub(now, nst->st_status_time));
  
  	/* get_task_comm isn't exported.  oh well. */
  	seq_printf(seq, "%p:\n"
  		   "  pid:          %lu\n"
  		   "  tgid:         %lu\n"
  		   "  process name: %s\n"
  		   "  node:         %u\n"
  		   "  sc:           %p\n"
  		   "  message id:   %d\n"
  		   "  message type: %u\n"
  		   "  message key:  0x%08x\n"
  		   "  sock acquiry: %lld usecs ago\n"
  		   "  send start:   %lld usecs ago\n"
  		   "  wait start:   %lld usecs ago\n",
  		   nst, (unsigned long)task_pid_nr(nst->st_task),
  		   (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,
  		   (long long)sock,
  		   (long long)send,
  		   (long long)status);
  
  out:
  	spin_unlock(&o2net_debug_lock);
  
  	return 0;
  }
  
  static void nst_seq_stop(struct seq_file *seq, void *v)
  {
  }
  
  static const 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;
  
  	dummy_nst = __seq_open_private(file, &nst_seq_ops, sizeof(*dummy_nst));
  	if (!dummy_nst)
  		return -ENOMEM;
  	o2net_debug_add_nst(dummy_nst);
  
  	return 0;
  }
  
  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 const 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);
  }
  
  struct o2net_sock_debug {
  	int dbg_ctxt;
  	struct o2net_sock_container *dbg_sock;
  };
  
  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_debug *sd = seq->private;
  	struct o2net_sock_container *sc, *dummy_sc = sd->dbg_sock;
  
  	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_debug *sd = seq->private;
  	struct o2net_sock_container *sc, *dummy_sc = sd->dbg_sock;
  
  	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 */
  }
  
  #ifdef CONFIG_OCFS2_FS_STATS
  # define sc_send_count(_s)		((_s)->sc_send_count)
  # define sc_recv_count(_s)		((_s)->sc_recv_count)
  # define sc_tv_acquiry_total_ns(_s)	(ktime_to_ns((_s)->sc_tv_acquiry_total))
  # define sc_tv_send_total_ns(_s)	(ktime_to_ns((_s)->sc_tv_send_total))
  # define sc_tv_status_total_ns(_s)	(ktime_to_ns((_s)->sc_tv_status_total))
  # define sc_tv_process_total_ns(_s)	(ktime_to_ns((_s)->sc_tv_process_total))
  #else
  # define sc_send_count(_s)		(0U)
  # define sc_recv_count(_s)		(0U)
  # define sc_tv_acquiry_total_ns(_s)	(0LL)
  # define sc_tv_send_total_ns(_s)	(0LL)
  # define sc_tv_status_total_ns(_s)	(0LL)
  # define sc_tv_process_total_ns(_s)	(0LL)
  #endif
  
  /* So that debugfs.ocfs2 can determine which format is being used */
  #define O2NET_STATS_STR_VERSION		1
  static void sc_show_sock_stats(struct seq_file *seq,
  			       struct o2net_sock_container *sc)
  {
  	if (!sc)
  		return;
  
  	seq_printf(seq, "%d,%u,%lu,%lld,%lld,%lld,%lu,%lld\n", O2NET_STATS_STR_VERSION,
  		   sc->sc_node->nd_num, (unsigned long)sc_send_count(sc),
  		   (long long)sc_tv_acquiry_total_ns(sc),
  		   (long long)sc_tv_send_total_ns(sc),
  		   (long long)sc_tv_status_total_ns(sc),
  		   (unsigned long)sc_recv_count(sc),
  		   (long long)sc_tv_process_total_ns(sc));
  }
  
  static void sc_show_sock_container(struct seq_file *seq,
  				   struct o2net_sock_container *sc)
  {
  	struct inet_sock *inet = NULL;
  	__be32 saddr = 0, daddr = 0;
  	__be16 sport = 0, dport = 0;
  
  	if (!sc)
  		return;
  
  	if (sc->sc_sock) {
  		inet = inet_sk(sc->sc_sock->sk);
  		/* the stack's structs aren't sparse endian clean */
  		saddr = (__force __be32)inet->inet_saddr;
  		daddr = (__force __be32)inet->inet_daddr;
  		sport = (__force __be16)inet->inet_sport;
  		dport = (__force __be16)inet->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:\n"
  		   "  krefs:           %d\n"
  		   "  sock:            %pI4:%u -> "
  				      "%pI4:%u\n"
  		   "  remote node:     %s\n"
  		   "  page off:        %zu\n"
  		   "  handshake ok:    %u\n"
  		   "  timer:           %lld usecs\n"
  		   "  data ready:      %lld usecs\n"
  		   "  advance start:   %lld usecs\n"
  		   "  advance stop:    %lld usecs\n"
  		   "  func start:      %lld usecs\n"
  		   "  func stop:       %lld usecs\n"
  		   "  func key:        0x%08x\n"
  		   "  func type:       %u\n",
  		   sc,
  		   kref_read(&sc->sc_kref),
  		   &saddr, inet ? ntohs(sport) : 0,
  		   &daddr, inet ? ntohs(dport) : 0,
  		   sc->sc_node->nd_name,
  		   sc->sc_page_off,
  		   sc->sc_handshake_ok,
  		   (long long)ktime_to_us(sc->sc_tv_timer),
  		   (long long)ktime_to_us(sc->sc_tv_data_ready),
  		   (long long)ktime_to_us(sc->sc_tv_advance_start),
  		   (long long)ktime_to_us(sc->sc_tv_advance_stop),
  		   (long long)ktime_to_us(sc->sc_tv_func_start),
  		   (long long)ktime_to_us(sc->sc_tv_func_stop),
  		   sc->sc_msg_key,
  		   sc->sc_msg_type);
  }
  
  static int sc_seq_show(struct seq_file *seq, void *v)
  {
  	struct o2net_sock_debug *sd = seq->private;
  	struct o2net_sock_container *sc, *dummy_sc = sd->dbg_sock;
  
  	spin_lock(&o2net_debug_lock);
  	sc = next_sc(dummy_sc);
  
  	if (sc) {
  		if (sd->dbg_ctxt == SHOW_SOCK_CONTAINERS)
  			sc_show_sock_container(seq, sc);
  		else
  			sc_show_sock_stats(seq, sc);
  	}
  
  	spin_unlock(&o2net_debug_lock);
  
  	return 0;
  }
  
  static void sc_seq_stop(struct seq_file *seq, void *v)
  {
  }
  
  static const 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_common_open(struct file *file, int ctxt)
  {
  	struct o2net_sock_debug *sd;
  	struct o2net_sock_container *dummy_sc;
  
  	dummy_sc = kzalloc(sizeof(*dummy_sc), GFP_KERNEL);
  	if (!dummy_sc)
  		return -ENOMEM;
  
  	sd = __seq_open_private(file, &sc_seq_ops, sizeof(*sd));
  	if (!sd) {
  		kfree(dummy_sc);
  		return -ENOMEM;
  	}
  
  	sd->dbg_ctxt = ctxt;
  	sd->dbg_sock = dummy_sc;
  
  	o2net_debug_add_sc(dummy_sc);
  
  	return 0;
  }
  
  static int sc_fop_release(struct inode *inode, struct file *file)
  {
  	struct seq_file *seq = file->private_data;
  	struct o2net_sock_debug *sd = seq->private;
  	struct o2net_sock_container *dummy_sc = sd->dbg_sock;
  
  	o2net_debug_del_sc(dummy_sc);
  	kfree(dummy_sc);
  	return seq_release_private(inode, file);
  }
  
  static int stats_fop_open(struct inode *inode, struct file *file)
  {
  	return sc_common_open(file, SHOW_SOCK_STATS);
  }
  
  static const struct file_operations stats_seq_fops = {
  	.open = stats_fop_open,
  	.read = seq_read,
  	.llseek = seq_lseek,
  	.release = sc_fop_release,
  };
  
  static int sc_fop_open(struct inode *inode, struct file *file)
  {
  	return sc_common_open(file, SHOW_SOCK_CONTAINERS);
  }
  
  static const struct file_operations sc_seq_fops = {
  	.open = sc_fop_open,
  	.read = seq_read,
  	.llseek = seq_lseek,
  	.release = sc_fop_release,
  };
  
  static int o2net_fill_bitmap(char *buf, int len)
  {
  	unsigned long map[BITS_TO_LONGS(O2NM_MAX_NODES)];
  	int i = -1, out = 0;
  
  	o2net_fill_node_map(map, sizeof(map));
  
  	while ((i = find_next_bit(map, O2NM_MAX_NODES, i + 1)) < O2NM_MAX_NODES)
  		out += scnprintf(buf + out, PAGE_SIZE - out, "%d ", i);
  	out += scnprintf(buf + out, PAGE_SIZE - out, "\n");
  
  	return out;
  }
  
  static int nodes_fop_open(struct inode *inode, struct file *file)
  {
  	char *buf;
  
  	buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
  	if (!buf)
  		return -ENOMEM;
  
  	i_size_write(inode, o2net_fill_bitmap(buf, PAGE_SIZE));
  
  	file->private_data = buf;
  
  	return 0;
  }
  
  static int o2net_debug_release(struct inode *inode, struct file *file)
  {
  	kfree(file->private_data);
  	return 0;
  }
  
  static ssize_t o2net_debug_read(struct file *file, char __user *buf,
  				size_t nbytes, loff_t *ppos)
  {
  	return simple_read_from_buffer(buf, nbytes, ppos, file->private_data,
  				       i_size_read(file->f_mapping->host));
  }
  
  static const struct file_operations nodes_fops = {
  	.open		= nodes_fop_open,
  	.release	= o2net_debug_release,
  	.read		= o2net_debug_read,
  	.llseek		= generic_file_llseek,
  };
  
  void o2net_debugfs_exit(void)
  {
  	debugfs_remove_recursive(o2net_dentry);
  }
  
  void o2net_debugfs_init(void)
  {
  	umode_t mode = S_IFREG|S_IRUSR;
  
  	o2net_dentry = debugfs_create_dir(O2NET_DEBUG_DIR, NULL);
  
  	debugfs_create_file(NST_DEBUG_NAME, mode, o2net_dentry, NULL,
  			    &nst_seq_fops);
  	debugfs_create_file(SC_DEBUG_NAME, mode, o2net_dentry, NULL,
  			    &sc_seq_fops);
  	debugfs_create_file(STATS_DEBUG_NAME, mode, o2net_dentry, NULL,
  			    &stats_seq_fops);
  	debugfs_create_file(NODES_DEBUG_NAME, mode, o2net_dentry, NULL,
  			    &nodes_fops);
  }
  
  #endif	/* CONFIG_DEBUG_FS */
  