// SPDX-License-Identifier: GPL-2.0-only
/*
* MLO link handling
*
* Copyright (C) 2022-2024 Intel Corporation
*/
#include <linux/slab.h>
#include <linux/kernel.h>
#include <net/mac80211.h>
#include "ieee80211_i.h"
#include "driver-ops.h"
#include "key.h"
#include "debugfs_netdev.h"
void ieee80211_link_setup(struct ieee80211_link_data *link)
{
if (link->sdata->vif.type == NL80211_IFTYPE_STATION)
ieee80211_mgd_setup_link(link);
}
void ieee80211_link_init(struct ieee80211_sub_if_data *sdata,
int link_id,
struct ieee80211_link_data *link,
struct ieee80211_bss_conf *link_conf)
{
bool deflink = link_id < 0;
if (link_id < 0)
link_id = 0;
rcu_assign_pointer(sdata->vif.link_conf[link_id], link_conf);
rcu_assign_pointer(sdata->link[link_id], link);
link->sdata = sdata;
link->link_id = link_id;
link->conf = link_conf;
link_conf->link_id = link_id;
link_conf->vif = &sdata->vif;
wiphy_work_init(&link->csa.finalize_work,
ieee80211_csa_finalize_work);
wiphy_work_init(&link->color_change_finalize_work,
ieee80211_color_change_finalize_work);
INIT_DELAYED_WORK(&link->color_collision_detect_work,
ieee80211_color_collision_detection_work);
INIT_LIST_HEAD(&link->assigned_chanctx_list);
INIT_LIST_HEAD(&link->reserved_chanctx_list);
wiphy_delayed_work_init(&link->dfs_cac_timer_work,
ieee80211_dfs_cac_timer_work);
if (!deflink) {
switch (sdata->vif.type) {
case NL80211_IFTYPE_AP:
ether_addr_copy(link_conf->addr,
sdata->wdev.links[link_id].addr);
link_conf->bssid = link_conf->addr;
WARN_ON(!(sdata->wdev.valid_links & BIT(link_id)));
break;
case NL80211_IFTYPE_STATION:
/* station sets the bssid in ieee80211_mgd_setup_link */
break;
default:
WARN_ON(1);
}
ieee80211_link_debugfs_add(link);
}
}
void ieee80211_link_stop(struct ieee80211_link_data *link)
{
if (link->sdata->vif.type == NL80211_IFTYPE_STATION)
ieee80211_mgd_stop_link(link);
cancel_delayed_work_sync(&link->color_collision_detect_work);
wiphy_work_cancel(link->sdata->local->hw.wiphy,
&link->color_change_finalize_work);
wiphy_work_cancel(link->sdata->local->hw.wiphy,
&link->csa.finalize_work);
if (link->sdata->wdev.links[link->link_id].cac_started) {
wiphy_delayed_work_cancel(link->sdata->local->hw.wiphy,
&link->dfs_cac_timer_work);
cfg80211_cac_event(link->sdata->dev,
&link->conf->chanreq.oper,
NL80211_RADAR_CAC_ABORTED,
GFP_KERNEL, link->link_id);
}
ieee80211_link_release_channel(link);
}
struct link_container {
struct ieee80211_link_data data;
struct ieee80211_bss_conf conf;
};
static void ieee80211_tear_down_links(struct ieee80211_sub_if_data *sdata,
struct link_container **links, u16 mask)
{
struct ieee80211_link_data *link;
LIST_HEAD(keys);
unsigned int link_id;
for (link_id = 0; link_id < IEEE80211_MLD_MAX_NUM_LINKS; link_id++) {
if (!(mask & BIT(link_id)))
continue;
link = &links[link_id]->data;
if (link_id == 0 && !link)
link = &sdata->deflink;
if (WARN_ON(!link))
continue;
ieee80211_remove_link_keys(link, &keys);
ieee80211_link_debugfs_remove(link);
ieee80211_link_stop(link);
}
synchronize_rcu();
ieee80211_free_key_list(sdata->local, &keys);
}
static void ieee80211_free_links(struct ieee80211_sub_if_data *sdata,
struct link_container **links)
{
unsigned int link_id;
for (link_id = 0; link_id < IEEE80211_MLD_MAX_NUM_LINKS; link_id++)
kfree(links[link_id]);
}
static int ieee80211_check_dup_link_addrs(struct ieee80211_sub_if_data *sdata)
{
unsigned int i, j;
for (i = 0; i < IEEE80211_MLD_MAX_NUM_LINKS; i++) {
struct ieee80211_link_data *link1;
link1 = sdata_dereference(sdata->link[i], sdata);
if (!link1)
continue;
for (j = i + 1; j < IEEE80211_MLD_MAX_NUM_LINKS; j++) {
struct ieee80211_link_data *link2;
link2 = sdata_dereference(sdata->link[j], sdata);
if (!link2)
continue;
if (ether_addr_equal(link1->conf->addr,
link2->conf->addr))
return -EALREADY;
}
}
return 0;
}
static void ieee80211_set_vif_links_bitmaps(struct ieee80211_sub_if_data *sdata,
u16 valid_links, u16 dormant_links)
{
sdata->vif.valid_links = valid_links;
sdata->vif.dormant_links = dormant_links;
if (!valid_links ||
WARN((~valid_links & dormant_links) ||
!(valid_links & ~dormant_links),
"Invalid links: valid=0x%x, dormant=0x%x",
valid_links, dormant_links)) {
sdata->vif.active_links = 0;
sdata->vif.dormant_links = 0;
return;
}
switch (sdata->vif.type) {
case NL80211_IFTYPE_AP:
/* in an AP all links are always active */
sdata->vif.active_links = valid_links;
/* AP links are not expected to be disabled */
WARN_ON(dormant_links);
break;
case NL80211_IFTYPE_STATION:
if (sdata->vif.active_links)
break;
sdata->vif.active_links = valid_links & ~dormant_links;
WARN_ON(hweight16(sdata->vif.active_links) > 1);
break;
default:
WARN_ON(1);
}
}
static int ieee80211_vif_update_links(struct ieee80211_sub_if_data *sdata,
struct link_container **to_free,
u16 new_links, u16 dormant_links)
{
u16 old_links = sdata->vif.valid_links;
u16 old_active = sdata->vif.active_links;
unsigned long add = new_links & ~old_links;
unsigned long rem = old_links & ~new_links;
unsigned int link_id;
int ret;
struct link_container *links[IEEE80211_MLD_MAX_NUM_LINKS] = {}, *link;
struct ieee80211_bss_conf *old[IEEE80211_MLD_MAX_NUM_LINKS];
struct ieee80211_link_data *old_data[IEEE80211_MLD_MAX_NUM_LINKS];
bool use_deflink = old_links == 0; /* set for error case */
lockdep_assert_wiphy(sdata->local->hw.wiphy);
memset(to_free, 0, sizeof(links));
if (old_links == new_links && dormant_links == sdata->vif.dormant_links)
return 0;
/* if there were no old links, need to clear the pointers to deflink */
if (!old_links)
rem |= BIT(0);
/* allocate new link structures first */
for_each_set_bit(link_id, &add, IEEE80211_MLD_MAX_NUM_LINKS) {
link = kzalloc(sizeof(*link), GFP_KERNEL);
if (!link) {
ret = -ENOMEM;
goto free;
}
links[link_id] = link;
}
/* keep track of the old pointers for the driver */
BUILD_BUG_ON(sizeof(old) != sizeof(sdata->vif.link_conf));
memcpy(old, sdata->vif.link_conf, sizeof(old));
/* and for us in error cases */
BUILD_BUG_ON(sizeof(old_data) != sizeof(sdata->link));
memcpy(old_data, sdata->link, sizeof(old_data));
/* grab old links to free later */
for_each_set_bit(link_id, &rem, IEEE80211_MLD_MAX_NUM_LINKS) {
if (rcu_access_pointer(sdata->link[link_id]) != &sdata->deflink) {
/*
* we must have allocated the data through this path so
* we know we can free both at the same time
*/
to_free[link_id] = container_of(rcu_access_pointer(sdata->link[link_id]),
typeof(*links[link_id]),
data);
}
RCU_INIT_POINTER(sdata->link[link_id], NULL);
RCU_INIT_POINTER(sdata->vif.link_conf[link_id], NULL);
}
if (!old_links)
ieee80211_debugfs_recreate_netdev(sdata, true);
/* link them into data structures */
for_each_set_bit(link_id, &add, IEEE80211_MLD_MAX_NUM_LINKS) {
WARN_ON(!use_deflink &&
rcu_access_pointer(sdata->link[link_id]) == &sdata->deflink);
link = links[link_id];
ieee80211_link_init(sdata, link_id, &link->data, &link->conf);
ieee80211_link_setup(&link->data);
}
if (new_links == 0)
ieee80211_link_init(sdata, -1, &sdata->deflink,
&sdata->vif.bss_conf);
ret = ieee80211_check_dup_link_addrs(sdata);
if (!ret) {
/* for keys we will not be able to undo this */
ieee80211_tear_down_links(sdata, to_free, rem);
ieee80211_set_vif_links_bitmaps(sdata, new_links, dormant_links);
/* tell the driver */
ret = drv_change_vif_links(sdata->local, sdata,
old_links & old_active,
new_links & sdata->vif.active_links,
old);
if (!new_links)
ieee80211_debugfs_recreate_netdev(sdata, false);
}
if (ret) {
/* restore config */
memcpy(sdata->link, old_data, sizeof(old_data));
memcpy(sdata->vif.link_conf, old, sizeof(old));
ieee80211_set_vif_links_bitmaps(sdata, old_links, dormant_links);
/* and free (only) the newly allocated links */
memset(to_free, 0, sizeof(links));
goto free;
}
/* use deflink/bss_conf again if and only if there are no more links */
use_deflink = new_links == 0;
goto deinit;
free:
/* if we failed during allocation, only free all */
for (link_id = 0; link_id < IEEE80211_MLD_MAX_NUM_LINKS; link_id++) {
kfree(links[link_id]);
links[link_id] = NULL;
}
deinit:
if (use_deflink)
ieee80211_link_init(sdata, -1, &sdata->deflink,
&sdata->vif.bss_conf);
return ret;
}
int ieee80211_vif_set_links(struct ieee80211_sub_if_data *sdata,
u16 new_links, u16 dormant_links)
{
struct link_container *links[IEEE80211_MLD_MAX_NUM_LINKS];
int ret;
ret = ieee80211_vif_update_links(sdata, links, new_links,
dormant_links);
ieee80211_free_links(sdata, links);
return ret;
}
static int _ieee80211_set_active_links(struct ieee80211_sub_if_data *sdata,
u16 active_links)
{
struct ieee80211_bss_conf *link_confs[IEEE80211_MLD_MAX_NUM_LINKS];
struct ieee80211_local *local = sdata->local;
u16 old_active = sdata->vif.active_links;
unsigned long rem = old_active & ~active_links;
unsigned long add = active_links & ~old_active;
struct sta_info *sta;
unsigned int link_id;
int ret, i;
if (!ieee80211_sdata_running(sdata))
return -ENETDOWN;
if (sdata->vif.type != NL80211_IFTYPE_STATION)
return -EINVAL;
if (active_links & ~ieee80211_vif_usable_links(&sdata->vif))
return -EINVAL;
/* nothing to do */
if (old_active == active_links)
return 0;
for (i = 0; i < IEEE80211_MLD_MAX_NUM_LINKS; i++)
link_confs[i] = sdata_dereference(sdata->vif.link_conf[i],
sdata);
if (add) {
sdata->vif.active_links |= active_links;
ret = drv_change_vif_links(local, sdata,
old_active,
sdata->vif.active_links,
link_confs);
if (ret) {
sdata->vif.active_links = old_active;
return ret;
}
}
for_each_set_bit(link_id, &rem, IEEE80211_MLD_MAX_NUM_LINKS) {
struct ieee80211_link_data *link;
link = sdata_dereference(sdata->link[link_id], sdata);
ieee80211_teardown_tdls_peers(link);
__ieee80211_link_release_channel(link, true);
/*
* If CSA is (still) active while the link is deactivated,
* just schedule the channel switch work for the time we
* had previously calculated, and we'll take the process
* from there.
*/
if (link->conf->csa_active)
wiphy_delayed_work_queue(local->hw.wiphy,
&link->u.mgd.csa.switch_work,
link->u.mgd.csa.time -
jiffies);
}
list_for_each_entry(sta, &local->sta_list, list) {
if (sdata != sta->sdata)
continue;
/* this is very temporary, but do it anyway */
__ieee80211_sta_recalc_aggregates(sta,
old_active | active_links);
ret = drv_change_sta_links(local, sdata, &sta->sta,
old_active,
old_active | active_links);
WARN_ON_ONCE(ret);
}
ret = ieee80211_key_switch_links(sdata, rem, add);
WARN_ON_ONCE(ret);
list_for_each_entry(sta, &local->sta_list, list) {
if (sdata != sta->sdata)
continue;
__ieee80211_sta_recalc_aggregates(sta, active_links);
ret = drv_change_sta_links(local, sdata, &sta->sta,
old_active | active_links,
active_links);
WARN_ON_ONCE(ret);
/*
* Do it again, just in case - the driver might very
* well have called ieee80211_sta_recalc_aggregates()
* from there when filling in the new links, which
* would set it wrong since the vif's active links are
* not switched yet...
*/
__ieee80211_sta_recalc_aggregates(sta, active_links);
}
for_each_set_bit(link_id, &add, IEEE80211_MLD_MAX_NUM_LINKS) {
struct ieee80211_link_data *link;
link = sdata_dereference(sdata->link[link_id], sdata);
/*
* This call really should not fail. Unfortunately, it appears
* that this may happen occasionally with some drivers. Should
* it happen, we are stuck in a bad place as going backwards is
* not really feasible.
*
* So lets just tell link_use_channel that it must not fail to
* assign the channel context (from mac80211's perspective) and
* assume the driver is going to trigger a recovery flow if it
* had a failure.
* That really is not great nor guaranteed to work. But at least
* the internal mac80211 state remains consistent and there is
* a chance that we can recover.
*/
ret = _ieee80211_link_use_channel(link,
&link->conf->chanreq,
IEEE80211_CHANCTX_SHARED,
true);
WARN_ON_ONCE(ret);
ieee80211_mgd_set_link_qos_params(link);
ieee80211_link_info_change_notify(sdata, link,
BSS_CHANGED_ERP_CTS_PROT |
BSS_CHANGED_ERP_PREAMBLE |
BSS_CHANGED_ERP_SLOT |
BSS_CHANGED_HT |
BSS_CHANGED_BASIC_RATES |
BSS_CHANGED_BSSID |
BSS_CHANGED_CQM |
BSS_CHANGED_QOS |
BSS_CHANGED_TXPOWER |
BSS_CHANGED_BANDWIDTH |
BSS_CHANGED_TWT |
BSS_CHANGED_HE_OBSS_PD |
BSS_CHANGED_HE_BSS_COLOR);
}
old_active = sdata->vif.active_links;
sdata->vif.active_links = active_links;
if (rem) {
ret = drv_change_vif_links(local, sdata, old_active,
active_links, link_confs);
WARN_ON_ONCE(ret);
}
return 0;
}
int ieee80211_set_active_links(struct ieee80211_vif *vif, u16 active_links)
{
struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
struct ieee80211_local *local = sdata->local;
u16 old_active;
int ret;
lockdep_assert_wiphy(local->hw.wiphy);
if (WARN_ON(!active_links))
return -EINVAL;
old_active = sdata->vif.active_links;
if (old_active == active_links)
return 0;
if (!drv_can_activate_links(local, sdata, active_links))
return -EINVAL;
if (old_active & active_links) {
/*
* if there's at least one link that stays active across
* the change then switch to it (to those) first, and
* then enable the additional links
*/
ret = _ieee80211_set_active_links(sdata,
old_active & active_links);
if (!ret)
ret = _ieee80211_set_active_links(sdata, active_links);
} else {
/* otherwise switch directly */
ret = _ieee80211_set_active_links(sdata, active_links);
}
return ret;
}
EXPORT_SYMBOL_GPL(ieee80211_set_active_links);
void ieee80211_set_active_links_async(struct ieee80211_vif *vif,
u16 active_links)
{
struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
if (WARN_ON(!active_links))
return;
if (!ieee80211_sdata_running(sdata))
return;
if (sdata->vif.type != NL80211_IFTYPE_STATION)
return;
if (active_links & ~ieee80211_vif_usable_links(&sdata->vif))
return;
/* nothing to do */
if (sdata->vif.active_links == active_links)
return;
sdata->desired_active_links = active_links;
wiphy_work_queue(sdata->local->hw.wiphy, &sdata->activate_links_work);
}
EXPORT_SYMBOL_GPL(ieee80211_set_active_links_async);
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