Johannes Berg | f444de0 | 2010-05-05 15:25:02 +0200 | [diff] [blame] | 1 | /* |
| 2 | * mac80211 - channel management |
| 3 | */ |
| 4 | |
Johannes Berg | 0aaffa9 | 2010-05-05 15:28:27 +0200 | [diff] [blame] | 5 | #include <linux/nl80211.h> |
Paul Stewart | 3117bbdb | 2012-03-13 07:46:18 -0700 | [diff] [blame] | 6 | #include <net/cfg80211.h> |
Johannes Berg | f444de0 | 2010-05-05 15:25:02 +0200 | [diff] [blame] | 7 | #include "ieee80211_i.h" |
Michal Kazior | 35f2fce | 2012-06-26 14:37:20 +0200 | [diff] [blame^] | 8 | #include "driver-ops.h" |
Johannes Berg | f444de0 | 2010-05-05 15:25:02 +0200 | [diff] [blame] | 9 | |
Johannes Berg | 368a07d | 2010-05-28 14:26:23 +0200 | [diff] [blame] | 10 | static enum ieee80211_chan_mode |
Johannes Berg | f444de0 | 2010-05-05 15:25:02 +0200 | [diff] [blame] | 11 | __ieee80211_get_channel_mode(struct ieee80211_local *local, |
| 12 | struct ieee80211_sub_if_data *ignore) |
| 13 | { |
| 14 | struct ieee80211_sub_if_data *sdata; |
| 15 | |
Johannes Berg | 46a5eba | 2010-09-15 13:28:15 +0200 | [diff] [blame] | 16 | lockdep_assert_held(&local->iflist_mtx); |
Johannes Berg | f444de0 | 2010-05-05 15:25:02 +0200 | [diff] [blame] | 17 | |
| 18 | list_for_each_entry(sdata, &local->interfaces, list) { |
| 19 | if (sdata == ignore) |
| 20 | continue; |
| 21 | |
| 22 | if (!ieee80211_sdata_running(sdata)) |
| 23 | continue; |
| 24 | |
Johannes Berg | e9980e6 | 2012-01-09 13:57:36 +0100 | [diff] [blame] | 25 | switch (sdata->vif.type) { |
| 26 | case NL80211_IFTYPE_MONITOR: |
Johannes Berg | f444de0 | 2010-05-05 15:25:02 +0200 | [diff] [blame] | 27 | continue; |
Johannes Berg | e9980e6 | 2012-01-09 13:57:36 +0100 | [diff] [blame] | 28 | case NL80211_IFTYPE_STATION: |
| 29 | if (!sdata->u.mgd.associated) |
| 30 | continue; |
| 31 | break; |
| 32 | case NL80211_IFTYPE_ADHOC: |
Johannes Berg | f444de0 | 2010-05-05 15:25:02 +0200 | [diff] [blame] | 33 | if (!sdata->u.ibss.ssid_len) |
| 34 | continue; |
| 35 | if (!sdata->u.ibss.fixed_channel) |
| 36 | return CHAN_MODE_HOPPING; |
Johannes Berg | e9980e6 | 2012-01-09 13:57:36 +0100 | [diff] [blame] | 37 | break; |
| 38 | case NL80211_IFTYPE_AP_VLAN: |
| 39 | /* will also have _AP interface */ |
Johannes Berg | f444de0 | 2010-05-05 15:25:02 +0200 | [diff] [blame] | 40 | continue; |
Johannes Berg | e9980e6 | 2012-01-09 13:57:36 +0100 | [diff] [blame] | 41 | case NL80211_IFTYPE_AP: |
| 42 | if (!sdata->u.ap.beacon) |
| 43 | continue; |
| 44 | break; |
Thomas Pedersen | be0f423 | 2012-05-13 22:24:08 -0700 | [diff] [blame] | 45 | case NL80211_IFTYPE_MESH_POINT: |
| 46 | if (!sdata->wdev.mesh_id_len) |
| 47 | continue; |
| 48 | break; |
Johannes Berg | e9980e6 | 2012-01-09 13:57:36 +0100 | [diff] [blame] | 49 | default: |
| 50 | break; |
| 51 | } |
Johannes Berg | f444de0 | 2010-05-05 15:25:02 +0200 | [diff] [blame] | 52 | |
| 53 | return CHAN_MODE_FIXED; |
| 54 | } |
| 55 | |
| 56 | return CHAN_MODE_UNDEFINED; |
| 57 | } |
| 58 | |
| 59 | enum ieee80211_chan_mode |
| 60 | ieee80211_get_channel_mode(struct ieee80211_local *local, |
| 61 | struct ieee80211_sub_if_data *ignore) |
| 62 | { |
| 63 | enum ieee80211_chan_mode mode; |
| 64 | |
| 65 | mutex_lock(&local->iflist_mtx); |
| 66 | mode = __ieee80211_get_channel_mode(local, ignore); |
| 67 | mutex_unlock(&local->iflist_mtx); |
| 68 | |
| 69 | return mode; |
| 70 | } |
Johannes Berg | 0aaffa9 | 2010-05-05 15:28:27 +0200 | [diff] [blame] | 71 | |
Michal Kazior | 23a85b45 | 2012-06-26 14:37:21 +0200 | [diff] [blame] | 72 | static enum nl80211_channel_type |
| 73 | ieee80211_get_superchan(struct ieee80211_local *local, |
| 74 | struct ieee80211_sub_if_data *sdata) |
Johannes Berg | 0aaffa9 | 2010-05-05 15:28:27 +0200 | [diff] [blame] | 75 | { |
Johannes Berg | 0aaffa9 | 2010-05-05 15:28:27 +0200 | [diff] [blame] | 76 | enum nl80211_channel_type superchan = NL80211_CHAN_NO_HT; |
Michal Kazior | 23a85b45 | 2012-06-26 14:37:21 +0200 | [diff] [blame] | 77 | struct ieee80211_sub_if_data *tmp; |
Johannes Berg | 0aaffa9 | 2010-05-05 15:28:27 +0200 | [diff] [blame] | 78 | |
| 79 | mutex_lock(&local->iflist_mtx); |
Johannes Berg | 0aaffa9 | 2010-05-05 15:28:27 +0200 | [diff] [blame] | 80 | list_for_each_entry(tmp, &local->interfaces, list) { |
| 81 | if (tmp == sdata) |
| 82 | continue; |
| 83 | |
| 84 | if (!ieee80211_sdata_running(tmp)) |
| 85 | continue; |
| 86 | |
| 87 | switch (tmp->vif.bss_conf.channel_type) { |
| 88 | case NL80211_CHAN_NO_HT: |
| 89 | case NL80211_CHAN_HT20: |
Felix Fietkau | 9db372f | 2011-03-11 21:45:51 +0100 | [diff] [blame] | 90 | if (superchan > tmp->vif.bss_conf.channel_type) |
| 91 | break; |
| 92 | |
Johannes Berg | 0aaffa9 | 2010-05-05 15:28:27 +0200 | [diff] [blame] | 93 | superchan = tmp->vif.bss_conf.channel_type; |
| 94 | break; |
| 95 | case NL80211_CHAN_HT40PLUS: |
| 96 | WARN_ON(superchan == NL80211_CHAN_HT40MINUS); |
| 97 | superchan = NL80211_CHAN_HT40PLUS; |
| 98 | break; |
| 99 | case NL80211_CHAN_HT40MINUS: |
| 100 | WARN_ON(superchan == NL80211_CHAN_HT40PLUS); |
| 101 | superchan = NL80211_CHAN_HT40MINUS; |
| 102 | break; |
| 103 | } |
| 104 | } |
Michal Kazior | 23a85b45 | 2012-06-26 14:37:21 +0200 | [diff] [blame] | 105 | mutex_unlock(&local->iflist_mtx); |
Johannes Berg | 0aaffa9 | 2010-05-05 15:28:27 +0200 | [diff] [blame] | 106 | |
Michal Kazior | 23a85b45 | 2012-06-26 14:37:21 +0200 | [diff] [blame] | 107 | return superchan; |
| 108 | } |
| 109 | |
| 110 | static bool |
| 111 | ieee80211_channel_types_are_compatible(enum nl80211_channel_type chantype1, |
| 112 | enum nl80211_channel_type chantype2, |
| 113 | enum nl80211_channel_type *compat) |
| 114 | { |
| 115 | /* |
| 116 | * start out with chantype1 being the result, |
| 117 | * overwriting later if needed |
| 118 | */ |
| 119 | if (compat) |
| 120 | *compat = chantype1; |
| 121 | |
| 122 | switch (chantype1) { |
Johannes Berg | 0aaffa9 | 2010-05-05 15:28:27 +0200 | [diff] [blame] | 123 | case NL80211_CHAN_NO_HT: |
Michal Kazior | 23a85b45 | 2012-06-26 14:37:21 +0200 | [diff] [blame] | 124 | if (compat) |
| 125 | *compat = chantype2; |
| 126 | break; |
Johannes Berg | 0aaffa9 | 2010-05-05 15:28:27 +0200 | [diff] [blame] | 127 | case NL80211_CHAN_HT20: |
| 128 | /* |
| 129 | * allow any change that doesn't go to no-HT |
| 130 | * (if it already is no-HT no change is needed) |
| 131 | */ |
Michal Kazior | 23a85b45 | 2012-06-26 14:37:21 +0200 | [diff] [blame] | 132 | if (chantype2 == NL80211_CHAN_NO_HT) |
Johannes Berg | 0aaffa9 | 2010-05-05 15:28:27 +0200 | [diff] [blame] | 133 | break; |
Michal Kazior | 23a85b45 | 2012-06-26 14:37:21 +0200 | [diff] [blame] | 134 | if (compat) |
| 135 | *compat = chantype2; |
Johannes Berg | 0aaffa9 | 2010-05-05 15:28:27 +0200 | [diff] [blame] | 136 | break; |
| 137 | case NL80211_CHAN_HT40PLUS: |
| 138 | case NL80211_CHAN_HT40MINUS: |
| 139 | /* allow smaller bandwidth and same */ |
Michal Kazior | 23a85b45 | 2012-06-26 14:37:21 +0200 | [diff] [blame] | 140 | if (chantype2 == NL80211_CHAN_NO_HT) |
Johannes Berg | 0aaffa9 | 2010-05-05 15:28:27 +0200 | [diff] [blame] | 141 | break; |
Michal Kazior | 23a85b45 | 2012-06-26 14:37:21 +0200 | [diff] [blame] | 142 | if (chantype2 == NL80211_CHAN_HT20) |
Johannes Berg | 0aaffa9 | 2010-05-05 15:28:27 +0200 | [diff] [blame] | 143 | break; |
Michal Kazior | 23a85b45 | 2012-06-26 14:37:21 +0200 | [diff] [blame] | 144 | if (chantype2 == chantype1) |
Johannes Berg | 0aaffa9 | 2010-05-05 15:28:27 +0200 | [diff] [blame] | 145 | break; |
Michal Kazior | 23a85b45 | 2012-06-26 14:37:21 +0200 | [diff] [blame] | 146 | return false; |
Johannes Berg | 0aaffa9 | 2010-05-05 15:28:27 +0200 | [diff] [blame] | 147 | } |
| 148 | |
Michal Kazior | 23a85b45 | 2012-06-26 14:37:21 +0200 | [diff] [blame] | 149 | return true; |
| 150 | } |
| 151 | |
| 152 | bool ieee80211_set_channel_type(struct ieee80211_local *local, |
| 153 | struct ieee80211_sub_if_data *sdata, |
| 154 | enum nl80211_channel_type chantype) |
| 155 | { |
| 156 | enum nl80211_channel_type superchan; |
| 157 | enum nl80211_channel_type compatchan; |
| 158 | |
| 159 | superchan = ieee80211_get_superchan(local, sdata); |
| 160 | if (!ieee80211_channel_types_are_compatible(superchan, chantype, |
| 161 | &compatchan)) |
| 162 | return false; |
| 163 | |
| 164 | local->_oper_channel_type = compatchan; |
Johannes Berg | 0aaffa9 | 2010-05-05 15:28:27 +0200 | [diff] [blame] | 165 | |
| 166 | if (sdata) |
| 167 | sdata->vif.bss_conf.channel_type = chantype; |
| 168 | |
Michal Kazior | 23a85b45 | 2012-06-26 14:37:21 +0200 | [diff] [blame] | 169 | return true; |
Johannes Berg | 0aaffa9 | 2010-05-05 15:28:27 +0200 | [diff] [blame] | 170 | |
Johannes Berg | 0aaffa9 | 2010-05-05 15:28:27 +0200 | [diff] [blame] | 171 | } |
Michal Kazior | d01a1e6 | 2012-06-26 14:37:16 +0200 | [diff] [blame] | 172 | |
| 173 | static struct ieee80211_chanctx * |
| 174 | ieee80211_find_chanctx(struct ieee80211_local *local, |
| 175 | struct ieee80211_channel *channel, |
| 176 | enum nl80211_channel_type channel_type, |
| 177 | enum ieee80211_chanctx_mode mode) |
| 178 | { |
| 179 | struct ieee80211_chanctx *ctx; |
| 180 | |
| 181 | lockdep_assert_held(&local->chanctx_mtx); |
| 182 | |
| 183 | if (mode == IEEE80211_CHANCTX_EXCLUSIVE) |
| 184 | return NULL; |
| 185 | if (WARN_ON(!channel)) |
| 186 | return NULL; |
| 187 | |
| 188 | list_for_each_entry(ctx, &local->chanctx_list, list) { |
| 189 | if (ctx->mode == IEEE80211_CHANCTX_EXCLUSIVE) |
| 190 | continue; |
| 191 | if (ctx->conf.channel != channel) |
| 192 | continue; |
| 193 | if (ctx->conf.channel_type != channel_type) |
| 194 | continue; |
| 195 | |
| 196 | return ctx; |
| 197 | } |
| 198 | |
| 199 | return NULL; |
| 200 | } |
| 201 | |
| 202 | static struct ieee80211_chanctx * |
| 203 | ieee80211_new_chanctx(struct ieee80211_local *local, |
| 204 | struct ieee80211_channel *channel, |
| 205 | enum nl80211_channel_type channel_type, |
| 206 | enum ieee80211_chanctx_mode mode) |
| 207 | { |
| 208 | struct ieee80211_chanctx *ctx; |
Michal Kazior | 35f2fce | 2012-06-26 14:37:20 +0200 | [diff] [blame^] | 209 | int err; |
Michal Kazior | d01a1e6 | 2012-06-26 14:37:16 +0200 | [diff] [blame] | 210 | |
| 211 | lockdep_assert_held(&local->chanctx_mtx); |
| 212 | |
| 213 | ctx = kzalloc(sizeof(*ctx) + local->hw.chanctx_data_size, GFP_KERNEL); |
| 214 | if (!ctx) |
| 215 | return ERR_PTR(-ENOMEM); |
| 216 | |
| 217 | ctx->conf.channel = channel; |
| 218 | ctx->conf.channel_type = channel_type; |
| 219 | ctx->mode = mode; |
| 220 | |
Michal Kazior | 35f2fce | 2012-06-26 14:37:20 +0200 | [diff] [blame^] | 221 | err = drv_add_chanctx(local, ctx); |
| 222 | if (err) { |
| 223 | kfree(ctx); |
| 224 | return ERR_PTR(err); |
| 225 | } |
| 226 | |
Michal Kazior | d01a1e6 | 2012-06-26 14:37:16 +0200 | [diff] [blame] | 227 | list_add(&ctx->list, &local->chanctx_list); |
| 228 | |
| 229 | return ctx; |
| 230 | } |
| 231 | |
| 232 | static void ieee80211_free_chanctx(struct ieee80211_local *local, |
| 233 | struct ieee80211_chanctx *ctx) |
| 234 | { |
| 235 | lockdep_assert_held(&local->chanctx_mtx); |
| 236 | |
| 237 | WARN_ON_ONCE(ctx->refcount != 0); |
| 238 | |
Michal Kazior | 35f2fce | 2012-06-26 14:37:20 +0200 | [diff] [blame^] | 239 | drv_remove_chanctx(local, ctx); |
| 240 | |
Michal Kazior | d01a1e6 | 2012-06-26 14:37:16 +0200 | [diff] [blame] | 241 | list_del(&ctx->list); |
| 242 | kfree_rcu(ctx, rcu_head); |
| 243 | } |
| 244 | |
| 245 | static int ieee80211_assign_vif_chanctx(struct ieee80211_sub_if_data *sdata, |
| 246 | struct ieee80211_chanctx *ctx) |
| 247 | { |
Michal Kazior | 35f2fce | 2012-06-26 14:37:20 +0200 | [diff] [blame^] | 248 | struct ieee80211_local *local = sdata->local; |
| 249 | int ret; |
Michal Kazior | d01a1e6 | 2012-06-26 14:37:16 +0200 | [diff] [blame] | 250 | |
| 251 | lockdep_assert_held(&local->chanctx_mtx); |
| 252 | |
Michal Kazior | 35f2fce | 2012-06-26 14:37:20 +0200 | [diff] [blame^] | 253 | ret = drv_assign_vif_chanctx(local, sdata, ctx); |
| 254 | if (ret) |
| 255 | return ret; |
| 256 | |
Michal Kazior | d01a1e6 | 2012-06-26 14:37:16 +0200 | [diff] [blame] | 257 | rcu_assign_pointer(sdata->vif.chanctx_conf, &ctx->conf); |
| 258 | ctx->refcount++; |
| 259 | |
| 260 | return 0; |
| 261 | } |
| 262 | |
| 263 | static void ieee80211_unassign_vif_chanctx(struct ieee80211_sub_if_data *sdata, |
| 264 | struct ieee80211_chanctx *ctx) |
| 265 | { |
Michal Kazior | 35f2fce | 2012-06-26 14:37:20 +0200 | [diff] [blame^] | 266 | struct ieee80211_local *local = sdata->local; |
Michal Kazior | d01a1e6 | 2012-06-26 14:37:16 +0200 | [diff] [blame] | 267 | |
| 268 | lockdep_assert_held(&local->chanctx_mtx); |
| 269 | |
| 270 | ctx->refcount--; |
| 271 | rcu_assign_pointer(sdata->vif.chanctx_conf, NULL); |
Michal Kazior | 35f2fce | 2012-06-26 14:37:20 +0200 | [diff] [blame^] | 272 | |
| 273 | drv_unassign_vif_chanctx(local, sdata, ctx); |
Michal Kazior | d01a1e6 | 2012-06-26 14:37:16 +0200 | [diff] [blame] | 274 | } |
| 275 | |
| 276 | static void __ieee80211_vif_release_channel(struct ieee80211_sub_if_data *sdata) |
| 277 | { |
| 278 | struct ieee80211_local *local = sdata->local; |
| 279 | struct ieee80211_chanctx_conf *conf; |
| 280 | struct ieee80211_chanctx *ctx; |
| 281 | |
| 282 | lockdep_assert_held(&local->chanctx_mtx); |
| 283 | |
| 284 | conf = rcu_dereference_protected(sdata->vif.chanctx_conf, |
| 285 | lockdep_is_held(&local->chanctx_mtx)); |
| 286 | if (!conf) |
| 287 | return; |
| 288 | |
| 289 | ctx = container_of(conf, struct ieee80211_chanctx, conf); |
| 290 | |
| 291 | ieee80211_unassign_vif_chanctx(sdata, ctx); |
| 292 | if (ctx->refcount == 0) |
| 293 | ieee80211_free_chanctx(local, ctx); |
| 294 | } |
| 295 | |
| 296 | int ieee80211_vif_use_channel(struct ieee80211_sub_if_data *sdata, |
| 297 | struct ieee80211_channel *channel, |
| 298 | enum nl80211_channel_type channel_type, |
| 299 | enum ieee80211_chanctx_mode mode) |
| 300 | { |
| 301 | struct ieee80211_local *local = sdata->local; |
| 302 | struct ieee80211_chanctx *ctx; |
| 303 | int ret; |
| 304 | |
| 305 | mutex_lock(&local->chanctx_mtx); |
| 306 | __ieee80211_vif_release_channel(sdata); |
| 307 | |
| 308 | ctx = ieee80211_find_chanctx(local, channel, channel_type, mode); |
| 309 | if (!ctx) |
| 310 | ctx = ieee80211_new_chanctx(local, channel, channel_type, mode); |
| 311 | if (IS_ERR(ctx)) { |
| 312 | ret = PTR_ERR(ctx); |
| 313 | goto out; |
| 314 | } |
| 315 | |
| 316 | ret = ieee80211_assign_vif_chanctx(sdata, ctx); |
| 317 | if (ret) { |
| 318 | /* if assign fails refcount stays the same */ |
| 319 | if (ctx->refcount == 0) |
| 320 | ieee80211_free_chanctx(local, ctx); |
| 321 | goto out; |
| 322 | } |
| 323 | |
| 324 | out: |
| 325 | mutex_unlock(&local->chanctx_mtx); |
| 326 | return ret; |
| 327 | } |
| 328 | |
| 329 | void ieee80211_vif_release_channel(struct ieee80211_sub_if_data *sdata) |
| 330 | { |
| 331 | mutex_lock(&sdata->local->chanctx_mtx); |
| 332 | __ieee80211_vif_release_channel(sdata); |
| 333 | mutex_unlock(&sdata->local->chanctx_mtx); |
| 334 | } |