| Message ID | 20210426190534.12667-3-alokad@codeaurora.org |
|---|---|
| State | Superseded |
| Headers | show |
| Series | [v10,1/4] nl80211: multiple bssid and EMA support in AP mode | expand |
On Mon, 2021-04-26 at 12:05 -0700, Aloka Dixit wrote: > > + * @IEEE80211_HW_SUPPORTS_MBSSID_AP: Hardware supports multiple BSSID > + * advertisements in AP mode. > + * @IEEE80211_HW_SUPPORTS_EMA_AP: Hardware supports enhanced multiple BSSID > + * advertisements in AP mode. Is there a good reason for these - the driver can just set the extended nl80211 flags instead and we can check, or nl80211 already checked? > > +static int ieee80211_set_mbssid_options(struct ieee80211_sub_if_data *sdata, > + struct cfg80211_mbssid_config params) > +{ > + struct ieee80211_local *local = sdata->local; > + struct wiphy *wiphy = local->hw.wiphy; > + struct net_device *parent; > + struct ieee80211_sub_if_data *psdata; > + > + if (!params.count || sdata->vif.type != NL80211_IFTYPE_AP || > + !ieee80211_hw_check(&local->hw, SUPPORTS_MBSSID_AP)) > + return -EINVAL; > + > + sdata->vif.mbssid.parent = NULL; > + sdata->vif.mbssid.flags = IEEE80211_VIF_MBSSID_TX; > + if (params.parent) { > + parent = __dev_get_by_index(wiphy_net(wiphy), params.parent); > + if (!parent || !parent->ieee80211_ptr) > + return -EINVAL; Hm wait, didn't I see the same code in cfg80211 - maybe cfg80211 should just pass the pointer? > > static int ieee80211_del_iface(struct wiphy *wiphy, struct wireless_dev *wdev) > { > + struct ieee80211_sub_if_data *sdata = IEEE80211_WDEV_TO_SUB_IF(wdev); > + struct ieee80211_local *local; > + struct ieee80211_vif *vif; > + > + if (!sdata) > + return 0; > + > + local = sdata->local; > + vif = &sdata->vif; > + if (vif->type == NL80211_IFTYPE_AP && > + ieee80211_hw_check(&local->hw, SUPPORTS_MBSSID_AP)) { > + if (vif->mbssid.flags & IEEE80211_VIF_MBSSID_TX) { > + struct ieee80211_sub_if_data *child, *tmpsdata; > + > + wiphy_unlock(local->hw.wiphy); > + mutex_lock(&local->iflist_mtx); I really don't think you can drop the locking like that in the middle of something. That's almost always a recipe for disaster. > @@ -375,6 +375,18 @@ static void ieee80211_do_stop(struct ieee80211_sub_if_data *sdata, bool going_do > struct cfg80211_chan_def chandef; > bool cancel_scan; > struct cfg80211_nan_func *func; > + struct ieee80211_sub_if_data *parent; > + > + if (sdata->vif.type == NL80211_IFTYPE_AP && > + ieee80211_hw_check(&local->hw, SUPPORTS_MBSSID_AP) && > + sdata->vif.mbssid.flags & IEEE80211_VIF_MBSSID_NON_TX) { > + parent = vif_to_sdata(sdata->vif.mbssid.parent); > + if (parent && ieee80211_sdata_running(parent)) { > + wiphy_unlock(local->hw.wiphy); > + dev_close(parent->wdev.netdev); > + wiphy_lock(local->hw.wiphy); Same here. johannes
On 2021-06-23 08:57, Johannes Berg wrote: > On Mon, 2021-04-26 at 12:05 -0700, Aloka Dixit wrote: >> > Hm wait, didn't I see the same code in cfg80211 - maybe cfg80211 should > just pass the pointer? >> >> static int ieee80211_del_iface(struct wiphy *wiphy, struct >> wireless_dev *wdev) >> { >> + struct ieee80211_sub_if_data *sdata = >> IEEE80211_WDEV_TO_SUB_IF(wdev); >> + struct ieee80211_local *local; >> + struct ieee80211_vif *vif; >> + >> + if (!sdata) >> + return 0; >> + >> + local = sdata->local; >> + vif = &sdata->vif; >> + if (vif->type == NL80211_IFTYPE_AP && >> + ieee80211_hw_check(&local->hw, SUPPORTS_MBSSID_AP)) { >> + if (vif->mbssid.flags & IEEE80211_VIF_MBSSID_TX) { >> + struct ieee80211_sub_if_data *child, *tmpsdata; >> + >> + wiphy_unlock(local->hw.wiphy); >> + mutex_lock(&local->iflist_mtx); > > I really don't think you can drop the locking like that in the middle > of > something. That's almost always a recipe for disaster. > >> @@ -375,6 +375,18 @@ static void ieee80211_do_stop(struct >> ieee80211_sub_if_data *sdata, bool going_do >> struct cfg80211_chan_def chandef; >> bool cancel_scan; >> struct cfg80211_nan_func *func; >> + struct ieee80211_sub_if_data *parent; >> + >> + if (sdata->vif.type == NL80211_IFTYPE_AP && >> + ieee80211_hw_check(&local->hw, SUPPORTS_MBSSID_AP) && >> + sdata->vif.mbssid.flags & IEEE80211_VIF_MBSSID_NON_TX) { >> + parent = vif_to_sdata(sdata->vif.mbssid.parent); >> + if (parent && ieee80211_sdata_running(parent)) { >> + wiphy_unlock(local->hw.wiphy); >> + dev_close(parent->wdev.netdev); >> + wiphy_lock(local->hw.wiphy); > > Same here. > > johannes Hi Johannes, Thanks for the comments, will go through all, but need your help with this particular one - I'm not able to come up with a different solution which does not cause a deadlock by continuing to hold wiphy_lock() as we discussed last time that dev_close() will in turn call into cfg80211. You had suggested looking at dev_close() for VLAN, that code also doesn't lock wiphy_lock hence I did same here but locked 'local->iflist_mtx'. Dropping both won't be good for sure. Can you please suggest a better way? I'm really not able to come up with one. Thanks.
Hi Aloka, > > > static int ieee80211_del_iface(struct wiphy *wiphy, struct > > > wireless_dev *wdev) > > > { > > > + struct ieee80211_sub_if_data *sdata = > > > IEEE80211_WDEV_TO_SUB_IF(wdev); > > > + struct ieee80211_local *local; > > > + struct ieee80211_vif *vif; > > > + > > > + if (!sdata) > > > + return 0; > > > + > > > + local = sdata->local; > > > + vif = &sdata->vif; > > > + if (vif->type == NL80211_IFTYPE_AP && > > > + ieee80211_hw_check(&local->hw, SUPPORTS_MBSSID_AP)) { > > > + if (vif->mbssid.flags & IEEE80211_VIF_MBSSID_TX) { > > > + struct ieee80211_sub_if_data *child, *tmpsdata; > > > + > > > + wiphy_unlock(local->hw.wiphy); > > > + mutex_lock(&local->iflist_mtx); > > > > I really don't think you can drop the locking like that in the middle > > of something. That's almost always a recipe for disaster. [...] > > I'm not able to come up with a different solution which does not cause a > deadlock by continuing to hold wiphy_lock() as we discussed last time > that dev_close() will in turn call into cfg80211. > > You had suggested looking at dev_close() for VLAN, that code also > doesn't lock wiphy_lock hence I did same here but locked > 'local->iflist_mtx'. Dropping both won't be good for sure. > > Can you please suggest a better way? I'm really not able to come up with > one. Yeah, it's a tricky one for sure, especially with the locking changes. Now that I look at this more closely - the code in ieee80211_del_iface() must be redundant since the interface has to go through ieee80211_do_stop() (perhaps during this) if it's actually up? However, I'm hnsure why you don't understand the VLAN code - see what I did in commit d5befb224edb ("mac80211: fix deadlock in AP/VLAN handling")? johannes
diff --git a/include/net/mac80211.h b/include/net/mac80211.h index 445b66c6eb7e..ca83bfe14355 100644 --- a/include/net/mac80211.h +++ b/include/net/mac80211.h @@ -631,6 +631,7 @@ struct ieee80211_fils_discovery { * @s1g: BSS is S1G BSS (affects Association Request format). * @beacon_tx_rate: The configured beacon transmit rate that needs to be passed * to driver when rate control is offloaded to firmware. + * @mbssid: Multiple bssid settings for AP mode */ struct ieee80211_bss_conf { const u8 *bssid; @@ -700,6 +701,7 @@ struct ieee80211_bss_conf { u32 unsol_bcast_probe_resp_interval; bool s1g; struct cfg80211_bitrate_mask beacon_tx_rate; + struct cfg80211_mbssid_config mbssid; }; /** @@ -1663,6 +1665,20 @@ enum ieee80211_offload_flags { IEEE80211_OFFLOAD_DECAP_ENABLED = BIT(2), }; +/** + * enum ieee80211_vif_mbssid_flags - virtual interface multiple bssid flags + * + * @IEEE80211_VIF_MBSSID_TX: Set for the transmitting profile. + * @IEEE80211_VIF_MBSSID_NON_TX: Set for non-transmitting profiles. + * @IEEE80211_VIF_MBSSID_EMA: Set when enhanced multi-BSS advertisements + * are enabled. + */ +enum ieee80211_vif_mbssid_flags { + IEEE80211_VIF_MBSSID_TX = BIT(1), + IEEE80211_VIF_MBSSID_NON_TX = BIT(2), + IEEE80211_VIF_MBSSID_EMA = BIT(3), +}; + /** * struct ieee80211_vif - per-interface data * @@ -1709,6 +1725,10 @@ enum ieee80211_offload_flags { * protected by fq->lock. * @offload_flags: 802.3 -> 802.11 enapsulation offload flags, see * &enum ieee80211_offload_flags. + * + * @mbssid: Multiple BSSID configurations. + * @mbssid.parent: Interface index of the transmitted BSS. + * @mbssid.flags: multiple bssid flags, see enum ieee80211_vif_mbssid_flags. */ struct ieee80211_vif { enum nl80211_iftype type; @@ -1737,6 +1757,11 @@ struct ieee80211_vif { bool txqs_stopped[IEEE80211_NUM_ACS]; + struct { + struct ieee80211_vif *parent; + u32 flags; + } mbssid; + /* must be last */ u8 drv_priv[] __aligned(sizeof(void *)); }; @@ -2381,7 +2406,7 @@ struct ieee80211_txq { * @IEEE80211_HW_TX_STATUS_NO_AMPDU_LEN: Driver does not report accurate A-MPDU * length in tx status information * - * @IEEE80211_HW_SUPPORTS_MULTI_BSSID: Hardware supports multi BSSID + * @IEEE80211_HW_SUPPORTS_MULTI_BSSID: Hardware supports multi BSSID in STA mode * * @IEEE80211_HW_SUPPORTS_ONLY_HE_MULTI_BSSID: Hardware supports multi BSSID * only for HE APs. Applies if @IEEE80211_HW_SUPPORTS_MULTI_BSSID is set. @@ -2402,6 +2427,11 @@ struct ieee80211_txq { * usage and 802.11 frames with %RX_FLAG_ONLY_MONITOR set for monitor to * the stack. * + * @IEEE80211_HW_SUPPORTS_MBSSID_AP: Hardware supports multiple BSSID + * advertisements in AP mode. + * @IEEE80211_HW_SUPPORTS_EMA_AP: Hardware supports enhanced multiple BSSID + * advertisements in AP mode. + * * @NUM_IEEE80211_HW_FLAGS: number of hardware flags, used for sizing arrays */ enum ieee80211_hw_flags { @@ -2457,6 +2487,8 @@ enum ieee80211_hw_flags { IEEE80211_HW_SUPPORTS_TX_ENCAP_OFFLOAD, IEEE80211_HW_SUPPORTS_RX_DECAP_OFFLOAD, IEEE80211_HW_SUPPORTS_CONC_MON_RX_DECAP, + IEEE80211_HW_SUPPORTS_MBSSID_AP, + IEEE80211_HW_SUPPORTS_EMA_AP, /* keep last, obviously */ NUM_IEEE80211_HW_FLAGS diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c index 7a99892e5aba..d1a965897b9d 100644 --- a/net/mac80211/cfg.c +++ b/net/mac80211/cfg.c @@ -111,6 +111,44 @@ static int ieee80211_set_mon_options(struct ieee80211_sub_if_data *sdata, return 0; } +static int ieee80211_set_mbssid_options(struct ieee80211_sub_if_data *sdata, + struct cfg80211_mbssid_config params) +{ + struct ieee80211_local *local = sdata->local; + struct wiphy *wiphy = local->hw.wiphy; + struct net_device *parent; + struct ieee80211_sub_if_data *psdata; + + if (!params.count || sdata->vif.type != NL80211_IFTYPE_AP || + !ieee80211_hw_check(&local->hw, SUPPORTS_MBSSID_AP)) + return -EINVAL; + + sdata->vif.mbssid.parent = NULL; + sdata->vif.mbssid.flags = IEEE80211_VIF_MBSSID_TX; + if (params.parent) { + parent = __dev_get_by_index(wiphy_net(wiphy), params.parent); + if (!parent || !parent->ieee80211_ptr) + return -EINVAL; + + psdata = IEEE80211_WDEV_TO_SUB_IF(parent->ieee80211_ptr); + if (psdata != sdata) { + if (psdata->vif.mbssid.parent) + return -EINVAL; + sdata->vif.mbssid.parent = &psdata->vif; + sdata->vif.mbssid.flags = IEEE80211_VIF_MBSSID_NON_TX; + } + } + + if (params.ema) { + if (!ieee80211_hw_check(&local->hw, SUPPORTS_EMA_AP)) + return -EINVAL; + sdata->vif.mbssid.flags |= IEEE80211_VIF_MBSSID_EMA; + } + + sdata->vif.bss_conf.mbssid = params; + return 0; +} + static struct wireless_dev *ieee80211_add_iface(struct wiphy *wiphy, const char *name, unsigned char name_assign_type, @@ -141,6 +179,36 @@ static struct wireless_dev *ieee80211_add_iface(struct wiphy *wiphy, static int ieee80211_del_iface(struct wiphy *wiphy, struct wireless_dev *wdev) { + struct ieee80211_sub_if_data *sdata = IEEE80211_WDEV_TO_SUB_IF(wdev); + struct ieee80211_local *local; + struct ieee80211_vif *vif; + + if (!sdata) + return 0; + + local = sdata->local; + vif = &sdata->vif; + if (vif->type == NL80211_IFTYPE_AP && + ieee80211_hw_check(&local->hw, SUPPORTS_MBSSID_AP)) { + if (vif->mbssid.flags & IEEE80211_VIF_MBSSID_TX) { + struct ieee80211_sub_if_data *child, *tmpsdata; + + wiphy_unlock(local->hw.wiphy); + mutex_lock(&local->iflist_mtx); + list_for_each_entry_safe(child, tmpsdata, + &local->interfaces, list) { + if (child->vif.mbssid.parent == vif && + ieee80211_sdata_running(child)) + dev_close(child->wdev.netdev); + } + mutex_unlock(&local->iflist_mtx); + wiphy_lock(local->hw.wiphy); + } else { + vif->mbssid.parent = NULL; + vif->mbssid.flags = 0; + } + } + ieee80211_if_remove(IEEE80211_WDEV_TO_SUB_IF(wdev)); return 0; @@ -1078,6 +1146,12 @@ static int ieee80211_start_ap(struct wiphy *wiphy, struct net_device *dev, changed |= BSS_CHANGED_HE_BSS_COLOR; } + if (params->mbssid.count) { + err = ieee80211_set_mbssid_options(sdata, params->mbssid); + if (err) + return err; + } + mutex_lock(&local->mtx); err = ieee80211_vif_use_channel(sdata, ¶ms->chandef, IEEE80211_CHANCTX_SHARED); diff --git a/net/mac80211/debugfs.c b/net/mac80211/debugfs.c index 9245c0421bda..00e5089a4a6c 100644 --- a/net/mac80211/debugfs.c +++ b/net/mac80211/debugfs.c @@ -457,6 +457,8 @@ static const char *hw_flag_names[] = { FLAG(SUPPORTS_TX_ENCAP_OFFLOAD), FLAG(SUPPORTS_RX_DECAP_OFFLOAD), FLAG(SUPPORTS_CONC_MON_RX_DECAP), + FLAG(SUPPORTS_MBSSID_AP), + FLAG(SUPPORTS_EMA_AP), #undef FLAG }; diff --git a/net/mac80211/iface.c b/net/mac80211/iface.c index b1c170939e44..1ab75d464569 100644 --- a/net/mac80211/iface.c +++ b/net/mac80211/iface.c @@ -375,6 +375,18 @@ static void ieee80211_do_stop(struct ieee80211_sub_if_data *sdata, bool going_do struct cfg80211_chan_def chandef; bool cancel_scan; struct cfg80211_nan_func *func; + struct ieee80211_sub_if_data *parent; + + if (sdata->vif.type == NL80211_IFTYPE_AP && + ieee80211_hw_check(&local->hw, SUPPORTS_MBSSID_AP) && + sdata->vif.mbssid.flags & IEEE80211_VIF_MBSSID_NON_TX) { + parent = vif_to_sdata(sdata->vif.mbssid.parent); + if (parent && ieee80211_sdata_running(parent)) { + wiphy_unlock(local->hw.wiphy); + dev_close(parent->wdev.netdev); + wiphy_lock(local->hw.wiphy); + } + } clear_bit(SDATA_STATE_RUNNING, &sdata->state);