net/wireless/debugfs.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * cfg80211 debugfs
   4  *
   5  * Copyright 2009       Luis R. Rodriguez <lrodriguez@atheros.com>
   6  * Copyright 2007       Johannes Berg <johannes@sipsolutions.net>
   7  */
   8
   9 #include <linux/slab.h>
  10 #include "core.h"
  11 #include "debugfs.h"
  12
  13 #define DEBUGFS_READONLY_FILE(name, buflen, fmt, value...)              \
  14 static ssize_t name## _read(struct file *file, char __user *userbuf,    \
  15                             size_t count, loff_t *ppos)                 \
  16 {                                                                       \
  17         struct wiphy *wiphy = file->private_data;                       \
  18         char buf[buflen];                                               \
  19         int res;                                                        \
  20                                                                         \
  21         res = scnprintf(buf, buflen, fmt "\n", ##value);                \
  22         return simple_read_from_buffer(userbuf, count, ppos, buf, res); \
  23 }                                                                       \
  24                                                                         \
  25 static const struct file_operations name## _ops = {                     \
  26         .read = name## _read,                                           \
  27         .open = simple_open,                                            \
  28         .llseek = generic_file_llseek,                                  \
  29 }
  30
  31 DEBUGFS_READONLY_FILE(rts_threshold, 20, "%d",
  32                       wiphy->rts_threshold);
  33 DEBUGFS_READONLY_FILE(fragmentation_threshold, 20, "%d",
  34                       wiphy->frag_threshold);
  35 DEBUGFS_READONLY_FILE(short_retry_limit, 20, "%d",
  36                       wiphy->retry_short);
  37 DEBUGFS_READONLY_FILE(long_retry_limit, 20, "%d",
  38                       wiphy->retry_long);
  39
  40 static int ht_print_chan(struct ieee80211_channel *chan,
  41                          char *buf, int buf_size, int offset)
  42 {
  43         if (WARN_ON(offset > buf_size))
  44                 return 0;
  45
  46         if (chan->flags & IEEE80211_CHAN_DISABLED)
  47                 return scnprintf(buf + offset,
  48                                  buf_size - offset,
  49                                  "%d Disabled\n",
  50                                  chan->center_freq);
  51
  52         return scnprintf(buf + offset,
  53                          buf_size - offset,
  54                          "%d HT40 %c%c\n",
  55                          chan->center_freq,
  56                          (chan->flags & IEEE80211_CHAN_NO_HT40MINUS) ?
  57                                 ' ' : '-',
  58                          (chan->flags & IEEE80211_CHAN_NO_HT40PLUS) ?
  59                                 ' ' : '+');
  60 }
  61
  62 static ssize_t ht40allow_map_read(struct file *file,
  63                                   char __user *user_buf,
  64                                   size_t count, loff_t *ppos)
  65 {
  66         struct wiphy *wiphy = file->private_data;
  67         char *buf;
  68         unsigned int offset = 0, buf_size = PAGE_SIZE, i, r;
  69         enum nl80211_band band;
  70         struct ieee80211_supported_band *sband;
  71
  72         buf = kzalloc(buf_size, GFP_KERNEL);
  73         if (!buf)
  74                 return -ENOMEM;
  75
  76         rtnl_lock();
  77
  78         for (band = 0; band < NUM_NL80211_BANDS; band++) {
  79                 sband = wiphy->bands[band];
  80                 if (!sband)
  81                         continue;
  82                 for (i = 0; i < sband->n_channels; i++)
  83                         offset += ht_print_chan(&sband->channels[i],
  84                                                 buf, buf_size, offset);
  85         }
  86
  87         rtnl_unlock();
  88
  89         r = simple_read_from_buffer(user_buf, count, ppos, buf, offset);
  90
  91         kfree(buf);
  92
  93         return r;
  94 }
  95
  96 static const struct file_operations ht40allow_map_ops = {
  97         .read = ht40allow_map_read,
  98         .open = simple_open,
  99         .llseek = default_llseek,
 100 };
 101
 102 #define DEBUGFS_ADD(name)                                               \
 103         debugfs_create_file(#name, 0444, phyd, &rdev->wiphy, &name## _ops)
 104
 105 void cfg80211_debugfs_rdev_add(struct cfg80211_registered_device *rdev)
 106 {
 107         struct dentry *phyd = rdev->wiphy.debugfsdir;
 108
 109         DEBUGFS_ADD(rts_threshold);
 110         DEBUGFS_ADD(fragmentation_threshold);
 111         DEBUGFS_ADD(short_retry_limit);
 112         DEBUGFS_ADD(long_retry_limit);
 113         DEBUGFS_ADD(ht40allow_map);
 114 }