From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6DA06C433EF for ; Fri, 15 Jul 2022 03:42:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232495AbiGODm0 (ORCPT ); Thu, 14 Jul 2022 23:42:26 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54496 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229481AbiGODmZ (ORCPT ); Thu, 14 Jul 2022 23:42:25 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 22CF776EB0 for ; Thu, 14 Jul 2022 20:42:23 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1657856542; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=nyKxt2XEtsC/aPZCk8DnRSFJexkBwqHFbw++HLQkWyY=; b=RV0qrdesP5FpXkLv6iOWbLEqY1IdMPxl2Yg6KcJtxpuucejuD7JLsC3nbudWm4E0GpJUSF S/9sC6PsSz1qBujycaNaKufSpj2mcgyJBLs1tmbLZK0LlaC9N7H0FP1CGdwlJ0QdnRBOZL LxZh1W2m9cb1v1LPJJQpKKFYzL+C9UI= Received: from mail-qk1-f198.google.com (mail-qk1-f198.google.com [209.85.222.198]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-499-eM4WQaLBPVy5Jpx8-9Eb8g-1; Thu, 14 Jul 2022 23:42:20 -0400 X-MC-Unique: eM4WQaLBPVy5Jpx8-9Eb8g-1 Received: by mail-qk1-f198.google.com with SMTP id s9-20020a05620a254900b006b54dd4d6deso2591409qko.3 for ; Thu, 14 Jul 2022 20:42:19 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=nyKxt2XEtsC/aPZCk8DnRSFJexkBwqHFbw++HLQkWyY=; b=K3TU/69Xr/Dq6/X2zCPNMY3Dj/AgKF7+vkeCsjDgYlnYDQcQsORM5IN8Y+gKDz/UZ6 HLeclGWQz+za9JSOZaE2KiC3WRe0b+UIsDyPd3xqljwkyN8tetgU39BdwsBkgaVQ5EPP G2JTnjCo3ZY+npc/hYcqBN8FttoJJAmthF3Y/l3qggRtqVetnJjiAURZpqlgV0a44hbi 7heYRYnOgYRxfQ6Bj6IKOoK9nWvHilF9HDs9c7iUFpjwxo2FSJ6ZYjakTDFQyxT+M1Wj D5xJEWQSujGkzCqfv/WzeTGdEaZpg6L7tR9Degmfw14cV4yFIAaLQi9Y94zwLCfQv48q 0kKg== X-Gm-Message-State: AJIora8HKgeL1d20yIoctk/kA2IiAl2kVpEz5q92mrEkXDJPTBtqiB7+ 3BS/Y888CHTKq22VoreGQKSpe7/4PhJUQ/Y9Gi6gT9BdSLrmpUYOqG9M14liGmmmvWYRcEQZeXc LIPAft70TErkRj3ezIkDVSM8GWM3fIS4BsiU5pA== X-Received: by 2002:ac8:5c12:0:b0:31e:9f86:1632 with SMTP id i18-20020ac85c12000000b0031e9f861632mr10573927qti.123.1657856539266; Thu, 14 Jul 2022 20:42:19 -0700 (PDT) X-Google-Smtp-Source: AGRyM1ttuYaz7Vxg+7YMNHvdG2QimNukxvYQAtVyx7dWlYHQ3OTSTftEefj4wafoNp2zjjsunfSRMUNmWQYnHJdWL+s= X-Received: by 2002:ac8:5c12:0:b0:31e:9f86:1632 with SMTP id i18-20020ac85c12000000b0031e9f861632mr10573912qti.123.1657856538939; Thu, 14 Jul 2022 20:42:18 -0700 (PDT) MIME-Version: 1.0 References: <20220701143052.1267509-1-miquel.raynal@bootlin.com> <20220701143052.1267509-11-miquel.raynal@bootlin.com> In-Reply-To: From: Alexander Aring Date: Thu, 14 Jul 2022 23:42:08 -0400 Message-ID: Subject: Re: [PATCH wpan-next 10/20] net: mac802154: Handle passive scanning To: Miquel Raynal Cc: Alexander Aring , Stefan Schmidt , linux-wpan - ML , "David S. Miller" , Jakub Kicinski , Paolo Abeni , Eric Dumazet , Network Development , David Girault , Romuald Despres , Frederic Blain , Nicolas Schodet , Thomas Petazzoni Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-wpan@vger.kernel.org Hi, On Thu, Jul 14, 2022 at 11:33 PM Alexander Aring wrote: > > Hi, > > On Fri, Jul 1, 2022 at 10:36 AM Miquel Raynal wrote: > > > > Implement the core hooks in order to provide the softMAC layer support > > for passive scans. Scans are requested by the user and can be aborted. > > > > Changing the channels is prohibited during the scan. > > > > As transceivers enter promiscuous mode during scans, they might stop > > checking frame validity so we ensure this gets done at mac level. > > > > The implementation uses a workqueue triggered at a certain interval > > depending on the symbol duration for the current channel and the > > duration order provided. > > > > Received beacons during a passive scan are processed also in a work > > queue and forwarded to the upper layer. > > > > Active scanning is not supported yet. > > > > Co-developed-by: David Girault > > Signed-off-by: David Girault > > Signed-off-by: Miquel Raynal > > --- > > include/linux/ieee802154.h | 4 + > > include/net/cfg802154.h | 12 ++ > > net/mac802154/Makefile | 2 +- > > net/mac802154/cfg.c | 39 ++++++ > > net/mac802154/ieee802154_i.h | 29 ++++ > > net/mac802154/iface.c | 6 + > > net/mac802154/main.c | 4 + > > net/mac802154/rx.c | 49 ++++++- > > net/mac802154/scan.c | 264 +++++++++++++++++++++++++++++++++++ > > 9 files changed, 405 insertions(+), 4 deletions(-) > > create mode 100644 net/mac802154/scan.c > > > > diff --git a/include/linux/ieee802154.h b/include/linux/ieee802154.h > > index 929d4e672575..94bfee22bd0a 100644 > > --- a/include/linux/ieee802154.h > > +++ b/include/linux/ieee802154.h > > @@ -47,6 +47,10 @@ > > /* Duration in superframe order */ > > #define IEEE802154_MAX_SCAN_DURATION 14 > > #define IEEE802154_ACTIVE_SCAN_DURATION 15 > > +/* Superframe duration in slots */ > > +#define IEEE802154_SUPERFRAME_PERIOD 16 > > +/* Various periods expressed in symbols */ > > +#define IEEE802154_SLOT_PERIOD 60 > > #define IEEE802154_LIFS_PERIOD 40 > > #define IEEE802154_SIFS_PERIOD 12 > > #define IEEE802154_MAX_SIFS_FRAME_SIZE 18 > > diff --git a/include/net/cfg802154.h b/include/net/cfg802154.h > > index f05ce3c45b5d..206283fd4b72 100644 > > --- a/include/net/cfg802154.h > > +++ b/include/net/cfg802154.h > > @@ -300,6 +300,18 @@ struct cfg802154_scan_request { > > struct wpan_phy *wpan_phy; > > }; > > > > +/** > > + * struct cfg802154_mac_pkt - MAC packet descriptor (beacon/command) > > + * @node: MAC packets to process list member > > + * @skb: the received sk_buff > > + * @sdata: the interface on which @skb was received > > + */ > > +struct cfg802154_mac_pkt { > > + struct list_head node; > > + struct sk_buff *skb; > > + struct ieee802154_sub_if_data *sdata; > > +}; > > + > > struct ieee802154_llsec_key_id { > > u8 mode; > > u8 id; > > diff --git a/net/mac802154/Makefile b/net/mac802154/Makefile > > index 4059295fdbf8..43d1347b37ee 100644 > > --- a/net/mac802154/Makefile > > +++ b/net/mac802154/Makefile > > @@ -1,6 +1,6 @@ > > # SPDX-License-Identifier: GPL-2.0-only > > obj-$(CONFIG_MAC802154) += mac802154.o > > mac802154-objs := main.o rx.o tx.o mac_cmd.o mib.o \ > > - iface.o llsec.o util.o cfg.o trace.o > > + iface.o llsec.o util.o cfg.o scan.o trace.o > > > > CFLAGS_trace.o := -I$(src) > > diff --git a/net/mac802154/cfg.c b/net/mac802154/cfg.c > > index 4116a894c86e..1f532d93d870 100644 > > --- a/net/mac802154/cfg.c > > +++ b/net/mac802154/cfg.c > > @@ -114,6 +114,10 @@ ieee802154_set_channel(struct wpan_phy *wpan_phy, u8 page, u8 channel) > > wpan_phy->current_channel == channel) > > return 0; > > > > + /* Refuse to change channels during a scanning operation */ > > + if (mac802154_is_scanning(local)) > > + return -EBUSY; > > + > > okay, that answered one of my other questions in another mail. > > > ret = drv_set_channel(local, page, channel); > > if (!ret) { > > wpan_phy->current_page = page; > > @@ -261,6 +265,39 @@ ieee802154_set_ackreq_default(struct wpan_phy *wpan_phy, > > return 0; > > } > > > > +static int mac802154_trigger_scan(struct wpan_phy *wpan_phy, > > + struct cfg802154_scan_request *request) > > +{ > > + struct ieee802154_local *local = wpan_phy_priv(wpan_phy); > > + struct ieee802154_sub_if_data *sdata; > > + int ret; > > + > > + sdata = IEEE802154_WPAN_DEV_TO_SUB_IF(request->wpan_dev); > > + > > + ASSERT_RTNL(); > > + > > + mutex_lock(&local->scan_lock); > > + ret = mac802154_trigger_scan_locked(sdata, request); > > + mutex_unlock(&local->scan_lock); > > + > > + return ret; > > +} > > + > > +static int mac802154_abort_scan(struct wpan_phy *wpan_phy, > > + struct wpan_dev *wpan_dev) > > +{ > > + struct ieee802154_local *local = wpan_phy_priv(wpan_phy); > > + int ret; > > + > > + ASSERT_RTNL(); > > + > > + mutex_lock(&local->scan_lock); > > + ret = mac802154_abort_scan_locked(local); > > + mutex_unlock(&local->scan_lock); > > + > > + return ret; > > +} > > + > > #ifdef CONFIG_IEEE802154_NL802154_EXPERIMENTAL > > static void > > ieee802154_get_llsec_table(struct wpan_phy *wpan_phy, > > @@ -468,6 +505,8 @@ const struct cfg802154_ops mac802154_config_ops = { > > .set_max_frame_retries = ieee802154_set_max_frame_retries, > > .set_lbt_mode = ieee802154_set_lbt_mode, > > .set_ackreq_default = ieee802154_set_ackreq_default, > > + .trigger_scan = mac802154_trigger_scan, > > + .abort_scan = mac802154_abort_scan, > > #ifdef CONFIG_IEEE802154_NL802154_EXPERIMENTAL > > .get_llsec_table = ieee802154_get_llsec_table, > > .lock_llsec_table = ieee802154_lock_llsec_table, > > diff --git a/net/mac802154/ieee802154_i.h b/net/mac802154/ieee802154_i.h > > index b8775bcc9003..46394e2e0486 100644 > > --- a/net/mac802154/ieee802154_i.h > > +++ b/net/mac802154/ieee802154_i.h > > @@ -21,6 +21,10 @@ > > > > #include "llsec.h" > > > > +enum ieee802154_ongoing { > > + IEEE802154_IS_SCANNING = BIT(0), > > +}; > > + > > /* mac802154 device private data */ > > struct ieee802154_local { > > struct ieee802154_hw hw; > > @@ -50,8 +54,19 @@ struct ieee802154_local { > > > > struct hrtimer ifs_timer; > > > > + /* Scanning */ > > + struct mutex scan_lock; > > + int scan_channel_idx; > > + struct cfg802154_scan_request __rcu *scan_req; > > + struct delayed_work scan_work; > > + > > + /* Asynchronous tasks */ > > + struct list_head rx_beacon_list; > > + struct work_struct rx_beacon_work; > > + > > bool started; > > bool suspended; > > + unsigned long ongoing; > > > > struct tasklet_struct tasklet; > > struct sk_buff_head skb_queue; > > @@ -210,6 +225,20 @@ void mac802154_unlock_table(struct net_device *dev); > > > > int mac802154_wpan_update_llsec(struct net_device *dev); > > > > +/* PAN management handling */ > > +void mac802154_scan_worker(struct work_struct *work); > > +int mac802154_trigger_scan_locked(struct ieee802154_sub_if_data *sdata, > > + struct cfg802154_scan_request *request); > > +int mac802154_abort_scan_locked(struct ieee802154_local *local); > > +int mac802154_process_beacon(struct ieee802154_local *local, > > + struct sk_buff *skb); > > +void mac802154_rx_beacon_worker(struct work_struct *work); > > + > > +static inline bool mac802154_is_scanning(struct ieee802154_local *local) > > +{ > > + return test_bit(IEEE802154_IS_SCANNING, &local->ongoing); > > +} > > + > > /* interface handling */ > > int ieee802154_iface_init(void); > > void ieee802154_iface_exit(void); > > diff --git a/net/mac802154/iface.c b/net/mac802154/iface.c > > index 7715e17d9ba1..431cc544dbf2 100644 > > --- a/net/mac802154/iface.c > > +++ b/net/mac802154/iface.c > > @@ -315,6 +315,12 @@ static int mac802154_slave_close(struct net_device *dev) > > > > ASSERT_RTNL(); > > > > + if (mac802154_is_scanning(local)) { > > + mutex_lock(&local->scan_lock); > > + mac802154_abort_scan_locked(local); > > + mutex_unlock(&local->scan_lock); > > + } > > + > > mutex_lock(&local->device_lock); > > > > netif_stop_queue(dev); > > diff --git a/net/mac802154/main.c b/net/mac802154/main.c > > index e5fb7ed73663..604fbc5b07df 100644 > > --- a/net/mac802154/main.c > > +++ b/net/mac802154/main.c > > @@ -89,14 +89,18 @@ ieee802154_alloc_hw(size_t priv_data_len, const struct ieee802154_ops *ops) > > local->ops = ops; > > > > INIT_LIST_HEAD(&local->interfaces); > > + INIT_LIST_HEAD(&local->rx_beacon_list); > > mutex_init(&local->iflist_mtx); > > mutex_init(&local->device_lock); > > + mutex_init(&local->scan_lock); > > > > tasklet_setup(&local->tasklet, ieee802154_tasklet_handler); > > > > skb_queue_head_init(&local->skb_queue); > > > > INIT_WORK(&local->sync_tx_work, ieee802154_xmit_sync_worker); > > + INIT_DELAYED_WORK(&local->scan_work, mac802154_scan_worker); > > + INIT_WORK(&local->rx_beacon_work, mac802154_rx_beacon_worker); > > > > /* init supported flags with 802.15.4 default ranges */ > > phy->supported.max_minbe = 8; > > diff --git a/net/mac802154/rx.c b/net/mac802154/rx.c > > index 39459d8d787a..0b1cf8c85ee9 100644 > > --- a/net/mac802154/rx.c > > +++ b/net/mac802154/rx.c > > @@ -29,11 +29,36 @@ static int ieee802154_deliver_skb(struct sk_buff *skb) > > return netif_receive_skb(skb); > > } > > > > +void mac802154_rx_beacon_worker(struct work_struct *work) > > +{ > > + struct ieee802154_local *local = > > + container_of(work, struct ieee802154_local, rx_beacon_work); > > + struct cfg802154_mac_pkt *mac_pkt; > > + > > + mutex_lock(&local->scan_lock); > > + > > + if (list_empty(&local->rx_beacon_list)) > > + goto unlock; > > + > > + mac_pkt = list_first_entry(&local->rx_beacon_list, > > + struct cfg802154_mac_pkt, node); > > + > > + mac802154_process_beacon(local, mac_pkt->skb); > > + > > + list_del(&mac_pkt->node); > > + kfree_skb(mac_pkt->skb); > > + kfree(mac_pkt); > > + > > +unlock: > > + mutex_unlock(&local->scan_lock); > > +} > > + > > static int > > ieee802154_subif_frame(struct ieee802154_sub_if_data *sdata, > > struct sk_buff *skb, const struct ieee802154_hdr *hdr) > > { > > struct wpan_dev *wpan_dev = &sdata->wpan_dev; > > + struct cfg802154_mac_pkt *mac_pkt; > > __le16 span, sshort; > > int rc; > > > > @@ -94,6 +119,18 @@ ieee802154_subif_frame(struct ieee802154_sub_if_data *sdata, > > > > switch (mac_cb(skb)->type) { > > case IEEE802154_FC_TYPE_BEACON: > > + if (!mac802154_is_scanning(sdata->local)) > > + goto fail; > > + > > + mac_pkt = kzalloc(sizeof(*mac_pkt), GFP_ATOMIC); > > + if (!mac_pkt) > > + goto fail; > > + > > + mac_pkt->skb = skb_get(skb); > > + mac_pkt->sdata = sdata; > > + list_add_tail(&mac_pkt->node, &sdata->local->rx_beacon_list); > > + queue_work(sdata->local->workqueue, &sdata->local->rx_beacon_work); > > + goto success; > > case IEEE802154_FC_TYPE_ACK: > > case IEEE802154_FC_TYPE_MAC_CMD: > > goto fail; > > @@ -109,6 +146,10 @@ ieee802154_subif_frame(struct ieee802154_sub_if_data *sdata, > > fail: > > kfree_skb(skb); > > return NET_RX_DROP; > > + > > +success: > > + kfree_skb(skb); > > + return NET_RX_SUCCESS; > > } > > > > static void > > @@ -268,10 +309,12 @@ void ieee802154_rx(struct ieee802154_local *local, struct sk_buff *skb) > > > > ieee802154_monitors_rx(local, skb); > > > > - /* Check if transceiver doesn't validate the checksum. > > - * If not we validate the checksum here. > > + /* Check if the transceiver doesn't validate the checksum, or if the > > + * check might have been disabled like during a scan. In these cases, > > + * we validate the checksum here. > > */ > > - if (local->hw.flags & IEEE802154_HW_RX_DROP_BAD_CKSUM) { > > + if (local->hw.flags & IEEE802154_HW_RX_DROP_BAD_CKSUM || > > + mac802154_is_scanning(local)) { > > crc = crc_ccitt(0, skb->data, skb->len); > > if (crc) { > > rcu_read_unlock(); > > diff --git a/net/mac802154/scan.c b/net/mac802154/scan.c > > new file mode 100644 > > index 000000000000..c74f6c3baa95 > > --- /dev/null > > +++ b/net/mac802154/scan.c > > @@ -0,0 +1,264 @@ > > +// SPDX-License-Identifier: GPL-2.0-only > > +/* > > + * IEEE 802.15.4 scanning management > > + * > > + * Copyright (C) Qorvo, 2021 > > + * Authors: > > + * - David Girault > > + * - Miquel Raynal > > + */ > > + > > +#include > > +#include > > +#include > > + > > +#include "ieee802154_i.h" > > +#include "driver-ops.h" > > +#include "../ieee802154/nl802154.h" > > + > > +static bool mac802154_check_promiscuous(struct ieee802154_local *local) > > +{ > > + struct ieee802154_sub_if_data *sdata; > > + bool promiscuous_on = false; > > + > > + /* Check if one subif is already in promiscuous mode. Since the list is > > + * protected by its own mutex, take it here to ensure no modification > > + * occurs during the check. > > + */ > > + rcu_read_lock(); > > + list_for_each_entry(sdata, &local->interfaces, list) { > > + if (ieee802154_sdata_running(sdata) && > > + sdata->wpan_dev.promiscuous_mode) { > > + /* At least one is in promiscuous mode */ > > + promiscuous_on = true; > > + break; > > + } > > + } > > + rcu_read_unlock(); > > + > > + return promiscuous_on; > > +} > > + > > +static int mac802154_set_promiscuous_mode(struct ieee802154_local *local, > > + bool state) > > +{ > > + bool promiscuous_on = mac802154_check_promiscuous(local); > > + int ret; > > + > > + if ((state && promiscuous_on) || (!state && !promiscuous_on)) > > + return 0; > > + > > + ret = drv_set_promiscuous_mode(local, state); > > + if (ret) > > + pr_err("Failed to %s promiscuous mode for SW scanning", > > + state ? "set" : "reset"); > > + > > + return ret; > > +} > > + > > +static int mac802154_send_scan_done(struct ieee802154_local *local) > > +{ > > + struct cfg802154_scan_request *scan_req; > > + struct wpan_phy *wpan_phy; > > + struct wpan_dev *wpan_dev; > > + > > + scan_req = rcu_dereference_protected(local->scan_req, > > + lockdep_is_held(&local->scan_lock)); > > + wpan_phy = scan_req->wpan_phy; > > + wpan_dev = scan_req->wpan_dev; > > + > > + cfg802154_flush_known_coordinators(wpan_dev); > > + > > + return nl802154_send_scan_done(wpan_phy, wpan_dev, scan_req); > > +} > > + > > +static int mac802154_end_of_scan(struct ieee802154_local *local) > > +{ > > + drv_set_channel(local, local->phy->current_page, > > + local->phy->current_channel); > > + ieee802154_configure_durations(local->phy, local->phy->current_page, > > + local->phy->current_channel); > > + clear_bit(IEEE802154_IS_SCANNING, &local->ongoing); > > + mac802154_set_promiscuous_mode(local, false); > > + ieee802154_mlme_op_post(local); > > + module_put(local->hw.parent->driver->owner); > > + > > + return mac802154_send_scan_done(local); > > +} > > + > > +int mac802154_abort_scan_locked(struct ieee802154_local *local) > > +{ > > + lockdep_assert_held(&local->scan_lock); > > + > > + if (!mac802154_is_scanning(local)) > > + return -ESRCH; > > + > > + cancel_delayed_work(&local->scan_work); > > + > > + return mac802154_end_of_scan(local); > > +} > > + > > +static unsigned int mac802154_scan_get_channel_time(u8 duration_order, > > + u8 symbol_duration) > > +{ > > + u64 base_super_frame_duration = (u64)symbol_duration * > > + IEEE802154_SUPERFRAME_PERIOD * IEEE802154_SLOT_PERIOD; > > + > > + return usecs_to_jiffies(base_super_frame_duration * > > + (BIT(duration_order) + 1)); > > +} > > + > > +void mac802154_flush_queued_beacons(struct ieee802154_local *local) > > +{ > > + struct cfg802154_mac_pkt *beacon, *tmp; > > + > > + lockdep_assert_held(&local->scan_lock); > > + > > + list_for_each_entry_safe(beacon, tmp, &local->rx_beacon_list, node) { > > + list_del(&beacon->node); > > + kfree_skb(beacon->skb); > > + kfree(beacon); > > + } > > +} > > + > > +void mac802154_scan_worker(struct work_struct *work) > > +{ > > + struct ieee802154_local *local = > > + container_of(work, struct ieee802154_local, scan_work.work); > > + struct cfg802154_scan_request *scan_req; > > + struct ieee802154_sub_if_data *sdata; > > + unsigned int scan_duration; > > + unsigned long chan; > > + int ret; > > + > > + mutex_lock(&local->scan_lock); > > + > > + if (!mac802154_is_scanning(local)) > > + goto unlock_mutex; > > + > > + scan_req = rcu_dereference_protected(local->scan_req, > > + lockdep_is_held(&local->scan_lock)); > > + sdata = IEEE802154_WPAN_DEV_TO_SUB_IF(scan_req->wpan_dev); > > + > > + if (local->suspended || !ieee802154_sdata_running(sdata)) > > + goto queue_work; > > + > > + do { > > + chan = find_next_bit((const unsigned long *)&scan_req->channels, > > + IEEE802154_MAX_CHANNEL + 1, > > + local->scan_channel_idx + 1); > > + > > + /* If there are no more channels left, complete the scan */ > > + if (chan > IEEE802154_MAX_CHANNEL) { > > + mac802154_end_of_scan(local); > > + goto unlock_mutex; > > + } > > + > > + /* Bypass the stack on purpose. As the channel change cannot be > > + * made atomic with regard to the incoming beacon flow, we flush > > + * the beacons list after changing the channel and before > > + * releasing the scan lock, to avoid processing beacons which > > + * have been received during this time frame. > > + */ > > + ret = drv_set_channel(local, scan_req->page, chan); > > + local->scan_channel_idx = chan; > > + ieee802154_configure_durations(local->phy, scan_req->page, chan); > > + mac802154_flush_queued_beacons(local); > > + } while (ret); > > + > > +queue_work: > > + scan_duration = mac802154_scan_get_channel_time(scan_req->duration, > > + local->phy->symbol_duration); > > + pr_debug("Scan channel %lu of page %u for %ums\n", > > + chan, scan_req->page, jiffies_to_msecs(scan_duration)); > > + queue_delayed_work(local->workqueue, &local->scan_work, scan_duration); > > + > > +unlock_mutex: > > + mutex_unlock(&local->scan_lock); > > +} > > + > > +int mac802154_trigger_scan_locked(struct ieee802154_sub_if_data *sdata, > > + struct cfg802154_scan_request *request) > > +{ > > + struct ieee802154_local *local = sdata->local; > > + int ret; > > + > > + lockdep_assert_held(&local->scan_lock); > > + > > + if (mac802154_is_scanning(local)) > > + return -EBUSY; > > + > > + /* TODO: support other scanning type */ > > + if (request->type != NL802154_SCAN_PASSIVE) > > + return -EOPNOTSUPP; > > + > > + /* Store scanning parameters */ > > + rcu_assign_pointer(local->scan_req, request); > > + > > + /* Software scanning requires to set promiscuous mode, so we need to > > + * pause the Tx queue during the entire operation. > > + */ > > + ieee802154_mlme_op_pre(local); > > + > > + ret = mac802154_set_promiscuous_mode(local, true); > > + if (ret) > > + goto cancel_mlme; > > I know some driver datasheets and as I said before, it's not allowed > to set promiscuous mode while in receive mode. We need to stop tx, > what we are doing. Then call stop() driver callback, > synchronize_net(), mac802154_set_promiscuous_mode(...), start(). The > same always for the opposite. s/always/as well/ I need to say, it needs to be something like that... we need to be careful here e.g. lots of monitor interfaces on one phy which has currently a serious use case for hwsim. We also don't need to do anything above if we already are in promiscuous mode, which might be worth checking. - Alex