linux/net/mac80211/chan.c
Johannes Berg 8a61af65c6 mac80211: fix channel context iteration
During suspend/resume channel contexts might be
iterated even if they haven't been re-added to
the driver, keep track of this and skip them in
iteration. Also use the new status for sanity
checks.

Also clarify the fact that during HW restart all
contexts are iterated over (thanks Eliad.)

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2013-01-03 13:01:35 +01:00

389 lines
9.4 KiB
C

/*
* mac80211 - channel management
*/
#include <linux/nl80211.h>
#include <linux/export.h>
#include <linux/rtnetlink.h>
#include <net/cfg80211.h>
#include "ieee80211_i.h"
#include "driver-ops.h"
static void ieee80211_change_chandef(struct ieee80211_local *local,
struct ieee80211_chanctx *ctx,
const struct cfg80211_chan_def *chandef)
{
if (cfg80211_chandef_identical(&ctx->conf.def, chandef))
return;
WARN_ON(!cfg80211_chandef_compatible(&ctx->conf.def, chandef));
ctx->conf.def = *chandef;
drv_change_chanctx(local, ctx, IEEE80211_CHANCTX_CHANGE_WIDTH);
if (!local->use_chanctx) {
local->_oper_channel_type = cfg80211_get_chandef_type(chandef);
ieee80211_hw_config(local, 0);
}
}
static struct ieee80211_chanctx *
ieee80211_find_chanctx(struct ieee80211_local *local,
const struct cfg80211_chan_def *chandef,
enum ieee80211_chanctx_mode mode)
{
struct ieee80211_chanctx *ctx;
lockdep_assert_held(&local->chanctx_mtx);
if (mode == IEEE80211_CHANCTX_EXCLUSIVE)
return NULL;
list_for_each_entry(ctx, &local->chanctx_list, list) {
const struct cfg80211_chan_def *compat;
if (ctx->mode == IEEE80211_CHANCTX_EXCLUSIVE)
continue;
compat = cfg80211_chandef_compatible(&ctx->conf.def, chandef);
if (!compat)
continue;
ieee80211_change_chandef(local, ctx, compat);
return ctx;
}
return NULL;
}
static struct ieee80211_chanctx *
ieee80211_new_chanctx(struct ieee80211_local *local,
const struct cfg80211_chan_def *chandef,
enum ieee80211_chanctx_mode mode)
{
struct ieee80211_chanctx *ctx;
int err;
lockdep_assert_held(&local->chanctx_mtx);
ctx = kzalloc(sizeof(*ctx) + local->hw.chanctx_data_size, GFP_KERNEL);
if (!ctx)
return ERR_PTR(-ENOMEM);
ctx->conf.def = *chandef;
ctx->conf.rx_chains_static = 1;
ctx->conf.rx_chains_dynamic = 1;
ctx->mode = mode;
if (!local->use_chanctx) {
local->_oper_channel_type =
cfg80211_get_chandef_type(chandef);
local->_oper_channel = chandef->chan;
ieee80211_hw_config(local, 0);
} else {
err = drv_add_chanctx(local, ctx);
if (err) {
kfree(ctx);
return ERR_PTR(err);
}
}
list_add_rcu(&ctx->list, &local->chanctx_list);
return ctx;
}
static void ieee80211_free_chanctx(struct ieee80211_local *local,
struct ieee80211_chanctx *ctx)
{
lockdep_assert_held(&local->chanctx_mtx);
WARN_ON_ONCE(ctx->refcount != 0);
if (!local->use_chanctx) {
local->_oper_channel_type = NL80211_CHAN_NO_HT;
ieee80211_hw_config(local, 0);
} else {
drv_remove_chanctx(local, ctx);
}
list_del_rcu(&ctx->list);
kfree_rcu(ctx, rcu_head);
}
static int ieee80211_assign_vif_chanctx(struct ieee80211_sub_if_data *sdata,
struct ieee80211_chanctx *ctx)
{
struct ieee80211_local *local = sdata->local;
int ret;
lockdep_assert_held(&local->chanctx_mtx);
ret = drv_assign_vif_chanctx(local, sdata, ctx);
if (ret)
return ret;
rcu_assign_pointer(sdata->vif.chanctx_conf, &ctx->conf);
ctx->refcount++;
ieee80211_recalc_txpower(sdata);
return 0;
}
static void ieee80211_recalc_chanctx_chantype(struct ieee80211_local *local,
struct ieee80211_chanctx *ctx)
{
struct ieee80211_chanctx_conf *conf = &ctx->conf;
struct ieee80211_sub_if_data *sdata;
const struct cfg80211_chan_def *compat = NULL;
lockdep_assert_held(&local->chanctx_mtx);
rcu_read_lock();
list_for_each_entry_rcu(sdata, &local->interfaces, list) {
if (!ieee80211_sdata_running(sdata))
continue;
if (rcu_access_pointer(sdata->vif.chanctx_conf) != conf)
continue;
if (!compat)
compat = &sdata->vif.bss_conf.chandef;
compat = cfg80211_chandef_compatible(
&sdata->vif.bss_conf.chandef, compat);
if (!compat)
break;
}
rcu_read_unlock();
if (WARN_ON_ONCE(!compat))
return;
ieee80211_change_chandef(local, ctx, compat);
}
static void ieee80211_unassign_vif_chanctx(struct ieee80211_sub_if_data *sdata,
struct ieee80211_chanctx *ctx)
{
struct ieee80211_local *local = sdata->local;
lockdep_assert_held(&local->chanctx_mtx);
ctx->refcount--;
rcu_assign_pointer(sdata->vif.chanctx_conf, NULL);
drv_unassign_vif_chanctx(local, sdata, ctx);
if (ctx->refcount > 0) {
ieee80211_recalc_chanctx_chantype(sdata->local, ctx);
ieee80211_recalc_smps_chanctx(local, ctx);
}
}
static void __ieee80211_vif_release_channel(struct ieee80211_sub_if_data *sdata)
{
struct ieee80211_local *local = sdata->local;
struct ieee80211_chanctx_conf *conf;
struct ieee80211_chanctx *ctx;
lockdep_assert_held(&local->chanctx_mtx);
conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
lockdep_is_held(&local->chanctx_mtx));
if (!conf)
return;
ctx = container_of(conf, struct ieee80211_chanctx, conf);
if (sdata->vif.type == NL80211_IFTYPE_AP) {
struct ieee80211_sub_if_data *vlan;
/* for the VLAN list */
ASSERT_RTNL();
list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
rcu_assign_pointer(vlan->vif.chanctx_conf, NULL);
}
ieee80211_unassign_vif_chanctx(sdata, ctx);
if (ctx->refcount == 0)
ieee80211_free_chanctx(local, ctx);
}
void ieee80211_recalc_smps_chanctx(struct ieee80211_local *local,
struct ieee80211_chanctx *chanctx)
{
struct ieee80211_sub_if_data *sdata;
u8 rx_chains_static, rx_chains_dynamic;
lockdep_assert_held(&local->chanctx_mtx);
rx_chains_static = 1;
rx_chains_dynamic = 1;
rcu_read_lock();
list_for_each_entry_rcu(sdata, &local->interfaces, list) {
u8 needed_static, needed_dynamic;
if (!ieee80211_sdata_running(sdata))
continue;
if (rcu_access_pointer(sdata->vif.chanctx_conf) !=
&chanctx->conf)
continue;
switch (sdata->vif.type) {
case NL80211_IFTYPE_P2P_DEVICE:
continue;
case NL80211_IFTYPE_STATION:
if (!sdata->u.mgd.associated)
continue;
break;
case NL80211_IFTYPE_AP_VLAN:
continue;
case NL80211_IFTYPE_AP:
case NL80211_IFTYPE_ADHOC:
case NL80211_IFTYPE_WDS:
case NL80211_IFTYPE_MESH_POINT:
break;
default:
WARN_ON_ONCE(1);
}
switch (sdata->smps_mode) {
default:
WARN_ONCE(1, "Invalid SMPS mode %d\n",
sdata->smps_mode);
/* fall through */
case IEEE80211_SMPS_OFF:
needed_static = sdata->needed_rx_chains;
needed_dynamic = sdata->needed_rx_chains;
break;
case IEEE80211_SMPS_DYNAMIC:
needed_static = 1;
needed_dynamic = sdata->needed_rx_chains;
break;
case IEEE80211_SMPS_STATIC:
needed_static = 1;
needed_dynamic = 1;
break;
}
rx_chains_static = max(rx_chains_static, needed_static);
rx_chains_dynamic = max(rx_chains_dynamic, needed_dynamic);
}
rcu_read_unlock();
if (!local->use_chanctx) {
if (rx_chains_static > 1)
local->smps_mode = IEEE80211_SMPS_OFF;
else if (rx_chains_dynamic > 1)
local->smps_mode = IEEE80211_SMPS_DYNAMIC;
else
local->smps_mode = IEEE80211_SMPS_STATIC;
ieee80211_hw_config(local, 0);
}
if (rx_chains_static == chanctx->conf.rx_chains_static &&
rx_chains_dynamic == chanctx->conf.rx_chains_dynamic)
return;
chanctx->conf.rx_chains_static = rx_chains_static;
chanctx->conf.rx_chains_dynamic = rx_chains_dynamic;
drv_change_chanctx(local, chanctx, IEEE80211_CHANCTX_CHANGE_RX_CHAINS);
}
int ieee80211_vif_use_channel(struct ieee80211_sub_if_data *sdata,
const struct cfg80211_chan_def *chandef,
enum ieee80211_chanctx_mode mode)
{
struct ieee80211_local *local = sdata->local;
struct ieee80211_chanctx *ctx;
int ret;
WARN_ON(sdata->dev && netif_carrier_ok(sdata->dev));
mutex_lock(&local->chanctx_mtx);
__ieee80211_vif_release_channel(sdata);
ctx = ieee80211_find_chanctx(local, chandef, mode);
if (!ctx)
ctx = ieee80211_new_chanctx(local, chandef, mode);
if (IS_ERR(ctx)) {
ret = PTR_ERR(ctx);
goto out;
}
sdata->vif.bss_conf.chandef = *chandef;
ret = ieee80211_assign_vif_chanctx(sdata, ctx);
if (ret) {
/* if assign fails refcount stays the same */
if (ctx->refcount == 0)
ieee80211_free_chanctx(local, ctx);
goto out;
}
if (sdata->vif.type == NL80211_IFTYPE_AP) {
struct ieee80211_sub_if_data *vlan;
/* for the VLAN list */
ASSERT_RTNL();
list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
rcu_assign_pointer(vlan->vif.chanctx_conf, &ctx->conf);
}
ieee80211_recalc_smps_chanctx(local, ctx);
out:
mutex_unlock(&local->chanctx_mtx);
return ret;
}
void ieee80211_vif_release_channel(struct ieee80211_sub_if_data *sdata)
{
WARN_ON(sdata->dev && netif_carrier_ok(sdata->dev));
mutex_lock(&sdata->local->chanctx_mtx);
__ieee80211_vif_release_channel(sdata);
mutex_unlock(&sdata->local->chanctx_mtx);
}
void ieee80211_vif_vlan_copy_chanctx(struct ieee80211_sub_if_data *sdata)
{
struct ieee80211_local *local = sdata->local;
struct ieee80211_sub_if_data *ap;
struct ieee80211_chanctx_conf *conf;
if (WARN_ON(sdata->vif.type != NL80211_IFTYPE_AP_VLAN || !sdata->bss))
return;
ap = container_of(sdata->bss, struct ieee80211_sub_if_data, u.ap);
mutex_lock(&local->chanctx_mtx);
conf = rcu_dereference_protected(ap->vif.chanctx_conf,
lockdep_is_held(&local->chanctx_mtx));
rcu_assign_pointer(sdata->vif.chanctx_conf, conf);
mutex_unlock(&local->chanctx_mtx);
}
void ieee80211_iter_chan_contexts_atomic(
struct ieee80211_hw *hw,
void (*iter)(struct ieee80211_hw *hw,
struct ieee80211_chanctx_conf *chanctx_conf,
void *data),
void *iter_data)
{
struct ieee80211_local *local = hw_to_local(hw);
struct ieee80211_chanctx *ctx;
rcu_read_lock();
list_for_each_entry_rcu(ctx, &local->chanctx_list, list)
if (ctx->driver_present)
iter(hw, &ctx->conf, iter_data);
rcu_read_unlock();
}
EXPORT_SYMBOL_GPL(ieee80211_iter_chan_contexts_atomic);