linux_dsm_epyc7002/net/batman-adv/log.c
Sven Eckelmann 0dacc7fab6 batman-adv: Allow to use BATMAN_ADV_DEBUG without BATMAN_ADV_DEBUGFS
The BATMAN_ADV_DEBUGFS portion of batman-adv is marked as deprecated. Thus
all required functionality should be available without it. The debug log
was already modified to also output via the kernel tracing function but
still retained its BATMAN_ADV_DEBUGFS functionality.

Separate the entry point for the debug log from the debugfs portions to
make it possible to build with BATMAN_ADV_DEBUG and without
BATMAN_ADV_DEBUGFS.

Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
2018-11-12 10:41:50 +01:00

268 lines
6.0 KiB
C

// SPDX-License-Identifier: GPL-2.0
/* Copyright (C) 2010-2018 B.A.T.M.A.N. contributors:
*
* Marek Lindner
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of version 2 of the GNU General Public
* License as published by the Free Software Foundation.
*
* 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, see <http://www.gnu.org/licenses/>.
*/
#include "log.h"
#include "main.h"
#include <linux/compiler.h>
#include <linux/debugfs.h>
#include <linux/errno.h>
#include <linux/eventpoll.h>
#include <linux/export.h>
#include <linux/fcntl.h>
#include <linux/fs.h>
#include <linux/gfp.h>
#include <linux/jiffies.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/poll.h>
#include <linux/sched.h> /* for linux/wait.h */
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/stddef.h>
#include <linux/types.h>
#include <linux/uaccess.h>
#include <linux/wait.h>
#include <stdarg.h>
#include "debugfs.h"
#include "trace.h"
#ifdef CONFIG_BATMAN_ADV_DEBUGFS
#define BATADV_LOG_BUFF_MASK (batadv_log_buff_len - 1)
static const int batadv_log_buff_len = BATADV_LOG_BUF_LEN;
static char *batadv_log_char_addr(struct batadv_priv_debug_log *debug_log,
size_t idx)
{
return &debug_log->log_buff[idx & BATADV_LOG_BUFF_MASK];
}
static void batadv_emit_log_char(struct batadv_priv_debug_log *debug_log,
char c)
{
char *char_addr;
char_addr = batadv_log_char_addr(debug_log, debug_log->log_end);
*char_addr = c;
debug_log->log_end++;
if (debug_log->log_end - debug_log->log_start > batadv_log_buff_len)
debug_log->log_start = debug_log->log_end - batadv_log_buff_len;
}
__printf(2, 3)
static int batadv_fdebug_log(struct batadv_priv_debug_log *debug_log,
const char *fmt, ...)
{
va_list args;
static char debug_log_buf[256];
char *p;
if (!debug_log)
return 0;
spin_lock_bh(&debug_log->lock);
va_start(args, fmt);
vscnprintf(debug_log_buf, sizeof(debug_log_buf), fmt, args);
va_end(args);
for (p = debug_log_buf; *p != 0; p++)
batadv_emit_log_char(debug_log, *p);
spin_unlock_bh(&debug_log->lock);
wake_up(&debug_log->queue_wait);
return 0;
}
static int batadv_log_open(struct inode *inode, struct file *file)
{
if (!try_module_get(THIS_MODULE))
return -EBUSY;
batadv_debugfs_deprecated(file,
"Use tracepoint batadv:batadv_dbg instead\n");
nonseekable_open(inode, file);
file->private_data = inode->i_private;
return 0;
}
static int batadv_log_release(struct inode *inode, struct file *file)
{
module_put(THIS_MODULE);
return 0;
}
static bool batadv_log_empty(struct batadv_priv_debug_log *debug_log)
{
return !(debug_log->log_start - debug_log->log_end);
}
static ssize_t batadv_log_read(struct file *file, char __user *buf,
size_t count, loff_t *ppos)
{
struct batadv_priv *bat_priv = file->private_data;
struct batadv_priv_debug_log *debug_log = bat_priv->debug_log;
int error, i = 0;
char *char_addr;
char c;
if ((file->f_flags & O_NONBLOCK) && batadv_log_empty(debug_log))
return -EAGAIN;
if (!buf)
return -EINVAL;
if (count == 0)
return 0;
if (!access_ok(VERIFY_WRITE, buf, count))
return -EFAULT;
error = wait_event_interruptible(debug_log->queue_wait,
(!batadv_log_empty(debug_log)));
if (error)
return error;
spin_lock_bh(&debug_log->lock);
while ((!error) && (i < count) &&
(debug_log->log_start != debug_log->log_end)) {
char_addr = batadv_log_char_addr(debug_log,
debug_log->log_start);
c = *char_addr;
debug_log->log_start++;
spin_unlock_bh(&debug_log->lock);
error = __put_user(c, buf);
spin_lock_bh(&debug_log->lock);
buf++;
i++;
}
spin_unlock_bh(&debug_log->lock);
if (!error)
return i;
return error;
}
static __poll_t batadv_log_poll(struct file *file, poll_table *wait)
{
struct batadv_priv *bat_priv = file->private_data;
struct batadv_priv_debug_log *debug_log = bat_priv->debug_log;
poll_wait(file, &debug_log->queue_wait, wait);
if (!batadv_log_empty(debug_log))
return EPOLLIN | EPOLLRDNORM;
return 0;
}
static const struct file_operations batadv_log_fops = {
.open = batadv_log_open,
.release = batadv_log_release,
.read = batadv_log_read,
.poll = batadv_log_poll,
.llseek = no_llseek,
};
/**
* batadv_debug_log_setup() - Initialize debug log
* @bat_priv: the bat priv with all the soft interface information
*
* Return: 0 on success or negative error number in case of failure
*/
int batadv_debug_log_setup(struct batadv_priv *bat_priv)
{
struct dentry *d;
if (!bat_priv->debug_dir)
goto err;
bat_priv->debug_log = kzalloc(sizeof(*bat_priv->debug_log), GFP_ATOMIC);
if (!bat_priv->debug_log)
goto err;
spin_lock_init(&bat_priv->debug_log->lock);
init_waitqueue_head(&bat_priv->debug_log->queue_wait);
d = debugfs_create_file("log", 0400, bat_priv->debug_dir, bat_priv,
&batadv_log_fops);
if (!d)
goto err;
return 0;
err:
return -ENOMEM;
}
/**
* batadv_debug_log_cleanup() - Destroy debug log
* @bat_priv: the bat priv with all the soft interface information
*/
void batadv_debug_log_cleanup(struct batadv_priv *bat_priv)
{
kfree(bat_priv->debug_log);
bat_priv->debug_log = NULL;
}
#endif /* CONFIG_BATMAN_ADV_DEBUGFS */
/**
* batadv_debug_log() - Add debug log entry
* @bat_priv: the bat priv with all the soft interface information
* @fmt: format string
*
* Return: 0 on success or negative error number in case of failure
*/
int batadv_debug_log(struct batadv_priv *bat_priv, const char *fmt, ...)
{
struct va_format vaf;
va_list args;
va_start(args, fmt);
vaf.fmt = fmt;
vaf.va = &args;
#ifdef CONFIG_BATMAN_ADV_DEBUGFS
batadv_fdebug_log(bat_priv->debug_log, "[%10u] %pV",
jiffies_to_msecs(jiffies), &vaf);
#endif
trace_batadv_dbg(bat_priv, &vaf);
va_end(args);
return 0;
}