debugfs.c

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/*
 * cfg80211 debugfs
 *
 * Copyright 2009   Luis R. Rodriguez <[email protected]>
 * Copyright 2007   Johannes Berg <[email protected]>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#include <linux/slab.h>
#include "core.h"
#include "debugfs.h"

#define DEBUGFS_READONLY_FILE(name, buflen, fmt, value...)      \
static ssize_t name## _read(struct file *file, char __user *userbuf,    \
                size_t count, loff_t *ppos)         \
{                                   \
    struct wiphy *wiphy= file->private_data;        \
    char buf[buflen];                       \
    int res;                            \
                                    \
    res = scnprintf(buf, buflen, fmt "\n", ##value);        \
    return simple_read_from_buffer(userbuf, count, ppos, buf, res); \
}                                   \
                                    \
static const struct file_operations name## _ops = {         \
    .read = name## _read,                       \
    .open = simple_open,                        \
    .llseek = generic_file_llseek,                  \
};

DEBUGFS_READONLY_FILE(rts_threshold, 20, "%d",
              wiphy->rts_threshold)
DEBUGFS_READONLY_FILE(fragmentation_threshold, 20, "%d",
              wiphy->frag_threshold);
DEBUGFS_READONLY_FILE(short_retry_limit, 20, "%d",
              wiphy->retry_short)
DEBUGFS_READONLY_FILE(long_retry_limit, 20, "%d",
              wiphy->retry_long);

static int ht_print_chan(struct ieee80211_channel *chan,
             char *buf, int buf_size, int offset)
{
    if (WARN_ON(offset > buf_size))
        return 0;

    if (chan->flags & IEEE80211_CHAN_DISABLED)
        return snprintf(buf + offset,
                buf_size - offset,
                "%d Disabled\n",
                chan->center_freq);

    return snprintf(buf + offset,
            buf_size - offset,
            "%d HT40 %c%c\n",
            chan->center_freq,
            (chan->flags & IEEE80211_CHAN_NO_HT40MINUS) ? ' ' : '-',
            (chan->flags & IEEE80211_CHAN_NO_HT40PLUS)  ? ' ' : '+');
}

static ssize_t ht40allow_map_read(struct file *file,
                  char __user *user_buf,
                  size_t count, loff_t *ppos)
{
    struct wiphy *wiphy = file->private_data;
    char *buf;
    unsigned int offset = 0, buf_size = PAGE_SIZE, i, r;
    enum ieee80211_band band;
    struct ieee80211_supported_band *sband;

    buf = kzalloc(buf_size, GFP_KERNEL);
    if (!buf)
        return -ENOMEM;

    mutex_lock(&cfg80211_mutex);

    for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
        sband = wiphy->bands[band];
        if (!sband)
            continue;
        for (i = 0; i < sband->n_channels; i++)
            offset += ht_print_chan(&sband->channels[i],
                        buf, buf_size, offset);
    }

    mutex_unlock(&cfg80211_mutex);

    r = simple_read_from_buffer(user_buf, count, ppos, buf, offset);

    kfree(buf);

    return r;
}

static const struct file_operations ht40allow_map_ops = {
    .read = ht40allow_map_read,
    .open = simple_open,
    .llseek = default_llseek,
};

#define DEBUGFS_ADD(name)                       \
    debugfs_create_file(#name, S_IRUGO, phyd, &rdev->wiphy, &name## _ops);

void cfg80211_debugfs_rdev_add(struct cfg80211_registered_device *rdev)
{
    struct dentry *phyd = rdev->wiphy.debugfsdir;

    DEBUGFS_ADD(rts_threshold);
    DEBUGFS_ADD(fragmentation_threshold);
    DEBUGFS_ADD(short_retry_limit);
    DEBUGFS_ADD(long_retry_limit);
    DEBUGFS_ADD(ht40allow_map);
}