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 * Copyright (C) 2023 Intel Corporation 8 */ 9 10 #include <linux/slab.h> 11 #include "core.h" 12 #include "debugfs.h" 13 14 #define DEBUGFS_READONLY_FILE(name, buflen, fmt, value...) \ 15 static ssize_t name## _read(struct file *file, char __user *userbuf, \ 16 size_t count, loff_t *ppos) \ 17 { \ 18 struct wiphy *wiphy = file->private_data; \ 19 char buf[buflen]; \ 20 int res; \ 21 \ 22 res = scnprintf(buf, buflen, fmt "\n", ##value); \ 23 return simple_read_from_buffer(userbuf, count, ppos, buf, res); \ 24 } \ 25 \ 26 static const struct file_operations name## _ops = { \ 27 .read = name## _read, \ 28 .open = simple_open, \ 29 .llseek = generic_file_llseek, \ 30 } 31 32 #define DEBUGFS_RADIO_READONLY_FILE(name, buflen, fmt, value...) \ 33 static ssize_t name## _read(struct file *file, char __user *userbuf, \ 34 size_t count, loff_t *ppos) \ 35 { \ 36 struct wiphy_radio_cfg *radio_cfg = file->private_data; \ 37 char buf[buflen]; \ 38 int res; \ 39 \ 40 res = scnprintf(buf, buflen, fmt "\n", ##value); \ 41 return simple_read_from_buffer(userbuf, count, ppos, buf, res); \ 42 } \ 43 \ 44 static const struct file_operations name## _ops = { \ 45 .read = name## _read, \ 46 .open = simple_open, \ 47 .llseek = generic_file_llseek, \ 48 } 49 50 DEBUGFS_READONLY_FILE(rts_threshold, 20, "%d", 51 wiphy->rts_threshold); 52 DEBUGFS_READONLY_FILE(fragmentation_threshold, 20, "%d", 53 wiphy->frag_threshold); 54 DEBUGFS_READONLY_FILE(short_retry_limit, 20, "%d", 55 wiphy->retry_short); 56 DEBUGFS_READONLY_FILE(long_retry_limit, 20, "%d", 57 wiphy->retry_long); 58 59 DEBUGFS_RADIO_READONLY_FILE(radio_rts_threshold, 20, "%d", 60 radio_cfg->rts_threshold); 61 62 static int ht_print_chan(struct ieee80211_channel *chan, 63 char *buf, int buf_size, int offset) 64 { 65 if (WARN_ON(offset > buf_size)) 66 return 0; 67 68 if (chan->flags & IEEE80211_CHAN_DISABLED) 69 return scnprintf(buf + offset, 70 buf_size - offset, 71 "%d Disabled\n", 72 chan->center_freq); 73 74 return scnprintf(buf + offset, 75 buf_size - offset, 76 "%d HT40 %c%c\n", 77 chan->center_freq, 78 (chan->flags & IEEE80211_CHAN_NO_HT40MINUS) ? 79 ' ' : '-', 80 (chan->flags & IEEE80211_CHAN_NO_HT40PLUS) ? 81 ' ' : '+'); 82 } 83 84 static ssize_t ht40allow_map_read(struct file *file, 85 char __user *user_buf, 86 size_t count, loff_t *ppos) 87 { 88 struct wiphy *wiphy = file->private_data; 89 char *buf; 90 unsigned int offset = 0, buf_size = PAGE_SIZE, i; 91 enum nl80211_band band; 92 struct ieee80211_supported_band *sband; 93 ssize_t r; 94 95 buf = kzalloc(buf_size, GFP_KERNEL); 96 if (!buf) 97 return -ENOMEM; 98 99 for (band = 0; band < NUM_NL80211_BANDS; band++) { 100 sband = wiphy->bands[band]; 101 if (!sband) 102 continue; 103 for (i = 0; i < sband->n_channels; i++) 104 offset += ht_print_chan(&sband->channels[i], 105 buf, buf_size, offset); 106 } 107 108 r = simple_read_from_buffer(user_buf, count, ppos, buf, offset); 109 110 kfree(buf); 111 112 return r; 113 } 114 115 static const struct file_operations ht40allow_map_ops = { 116 .read = ht40allow_map_read, 117 .open = simple_open, 118 .llseek = default_llseek, 119 }; 120 121 #define DEBUGFS_ADD(name) \ 122 debugfs_create_file(#name, 0444, phyd, &rdev->wiphy, &name## _ops) 123 124 #define DEBUGFS_RADIO_ADD(name, radio_idx) \ 125 debugfs_create_file(#name, 0444, radiod, \ 126 &rdev->wiphy.radio_cfg[radio_idx], \ 127 &name## _ops) 128 129 void cfg80211_debugfs_rdev_add(struct cfg80211_registered_device *rdev) 130 { 131 struct dentry *phyd = rdev->wiphy.debugfsdir; 132 struct dentry *radiod; 133 u8 i; 134 135 DEBUGFS_ADD(rts_threshold); 136 DEBUGFS_ADD(fragmentation_threshold); 137 DEBUGFS_ADD(short_retry_limit); 138 DEBUGFS_ADD(long_retry_limit); 139 DEBUGFS_ADD(ht40allow_map); 140 141 for (i = 0; i < rdev->wiphy.n_radio; i++) { 142 radiod = rdev->wiphy.radio_cfg[i].radio_debugfsdir; 143 DEBUGFS_RADIO_ADD(radio_rts_threshold, i); 144 } 145 } 146 147 struct debugfs_read_work { 148 struct wiphy_work work; 149 ssize_t (*handler)(struct wiphy *wiphy, 150 struct file *file, 151 char *buf, 152 size_t count, 153 void *data); 154 struct wiphy *wiphy; 155 struct file *file; 156 char *buf; 157 size_t bufsize; 158 void *data; 159 ssize_t ret; 160 struct completion completion; 161 }; 162 163 static void wiphy_locked_debugfs_read_work(struct wiphy *wiphy, 164 struct wiphy_work *work) 165 { 166 struct debugfs_read_work *w = container_of(work, typeof(*w), work); 167 168 w->ret = w->handler(w->wiphy, w->file, w->buf, w->bufsize, w->data); 169 complete(&w->completion); 170 } 171 172 static void wiphy_locked_debugfs_read_cancel(struct dentry *dentry, 173 void *data) 174 { 175 struct debugfs_read_work *w = data; 176 177 wiphy_work_cancel(w->wiphy, &w->work); 178 complete(&w->completion); 179 } 180 181 ssize_t wiphy_locked_debugfs_read(struct wiphy *wiphy, struct file *file, 182 char *buf, size_t bufsize, 183 char __user *userbuf, size_t count, 184 loff_t *ppos, 185 ssize_t (*handler)(struct wiphy *wiphy, 186 struct file *file, 187 char *buf, 188 size_t bufsize, 189 void *data), 190 void *data) 191 { 192 struct debugfs_read_work work = { 193 .handler = handler, 194 .wiphy = wiphy, 195 .file = file, 196 .buf = buf, 197 .bufsize = bufsize, 198 .data = data, 199 .ret = -ENODEV, 200 .completion = COMPLETION_INITIALIZER_ONSTACK(work.completion), 201 }; 202 struct debugfs_cancellation cancellation = { 203 .cancel = wiphy_locked_debugfs_read_cancel, 204 .cancel_data = &work, 205 }; 206 207 /* don't leak stack data or whatever */ 208 memset(buf, 0, bufsize); 209 210 wiphy_work_init(&work.work, wiphy_locked_debugfs_read_work); 211 wiphy_work_queue(wiphy, &work.work); 212 213 debugfs_enter_cancellation(file, &cancellation); 214 wait_for_completion(&work.completion); 215 debugfs_leave_cancellation(file, &cancellation); 216 217 if (work.ret < 0) 218 return work.ret; 219 220 if (WARN_ON(work.ret > bufsize)) 221 return -EINVAL; 222 223 return simple_read_from_buffer(userbuf, count, ppos, buf, work.ret); 224 } 225 EXPORT_SYMBOL_GPL(wiphy_locked_debugfs_read); 226 227 struct debugfs_write_work { 228 struct wiphy_work work; 229 ssize_t (*handler)(struct wiphy *wiphy, 230 struct file *file, 231 char *buf, 232 size_t count, 233 void *data); 234 struct wiphy *wiphy; 235 struct file *file; 236 char *buf; 237 size_t count; 238 void *data; 239 ssize_t ret; 240 struct completion completion; 241 }; 242 243 static void wiphy_locked_debugfs_write_work(struct wiphy *wiphy, 244 struct wiphy_work *work) 245 { 246 struct debugfs_write_work *w = container_of(work, typeof(*w), work); 247 248 w->ret = w->handler(w->wiphy, w->file, w->buf, w->count, w->data); 249 complete(&w->completion); 250 } 251 252 static void wiphy_locked_debugfs_write_cancel(struct dentry *dentry, 253 void *data) 254 { 255 struct debugfs_write_work *w = data; 256 257 wiphy_work_cancel(w->wiphy, &w->work); 258 complete(&w->completion); 259 } 260 261 ssize_t wiphy_locked_debugfs_write(struct wiphy *wiphy, 262 struct file *file, char *buf, size_t bufsize, 263 const char __user *userbuf, size_t count, 264 ssize_t (*handler)(struct wiphy *wiphy, 265 struct file *file, 266 char *buf, 267 size_t count, 268 void *data), 269 void *data) 270 { 271 struct debugfs_write_work work = { 272 .handler = handler, 273 .wiphy = wiphy, 274 .file = file, 275 .buf = buf, 276 .count = count, 277 .data = data, 278 .ret = -ENODEV, 279 .completion = COMPLETION_INITIALIZER_ONSTACK(work.completion), 280 }; 281 struct debugfs_cancellation cancellation = { 282 .cancel = wiphy_locked_debugfs_write_cancel, 283 .cancel_data = &work, 284 }; 285 286 /* mostly used for strings so enforce NUL-termination for safety */ 287 if (count >= bufsize) 288 return -EINVAL; 289 290 memset(buf, 0, bufsize); 291 292 if (copy_from_user(buf, userbuf, count)) 293 return -EFAULT; 294 295 wiphy_work_init(&work.work, wiphy_locked_debugfs_write_work); 296 wiphy_work_queue(wiphy, &work.work); 297 298 debugfs_enter_cancellation(file, &cancellation); 299 wait_for_completion(&work.completion); 300 debugfs_leave_cancellation(file, &cancellation); 301 302 return work.ret; 303 } 304 EXPORT_SYMBOL_GPL(wiphy_locked_debugfs_write); 305