From 6335698e24ec11e1324b916177da6721df724dd8 Mon Sep 17 00:00:00 2001
From: Benjamin Beichler <benjamin.beichler@uni-rostock.de>
Date: Mon, 22 Jan 2018 18:04:37 +0100
Subject: [PATCH] mac80211_hwsim: add generation count for netlink dump operation
Git-commit: 6335698e24ec11e1324b916177da6721df724dd8
Patch-mainline: v4.17-rc1
References: FATE#326294
Make the dump operation aware of changes on radio list and corresponding
inconsistent dumps. Changed variable name for better understanding.
Signed-off-by: Benjamin Beichler <benjamin.beichler@uni-rostock.de>
[compress ternary operator]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/net/wireless/mac80211_hwsim.c | 31 ++++++++++++++++++++++++-------
1 file changed, 24 insertions(+), 7 deletions(-)
--- a/drivers/net/wireless/mac80211_hwsim.c
+++ b/drivers/net/wireless/mac80211_hwsim.c
@@ -493,6 +493,7 @@ static LIST_HEAD(hwsim_radios);
static struct workqueue_struct *hwsim_wq;
static struct rhashtable hwsim_radios_rht;
static int hwsim_radio_idx;
+static int hwsim_radios_generation = 1;
static struct platform_driver mac80211_hwsim_driver = {
.driver = {
@@ -2792,6 +2793,7 @@ static int mac80211_hwsim_new_radio(stru
}
list_add_tail(&data->list, &hwsim_radios);
+ hwsim_radios_generation++;
spin_unlock_bh(&hwsim_radio_lock);
if (idx > 0)
@@ -3249,6 +3251,7 @@ static int hwsim_del_radio_nl(struct sk_
list_del(&data->list);
rhashtable_remove_fast(&hwsim_radios_rht, &data->rht,
hwsim_rht_params);
+ hwsim_radios_generation++;
spin_unlock_bh(&hwsim_radio_lock);
mac80211_hwsim_del_radio(data, wiphy_name(data->hw->wiphy),
info);
@@ -3305,17 +3308,19 @@ out_err:
static int hwsim_dump_radio_nl(struct sk_buff *skb,
struct netlink_callback *cb)
{
- int idx = cb->args[0];
+ int last_idx = cb->args[0];
struct mac80211_hwsim_data *data = NULL;
- int res;
+ int res = 0;
+ void *hdr;
spin_lock_bh(&hwsim_radio_lock);
+ cb->seq = hwsim_radios_generation;
- if (idx == hwsim_radio_idx)
+ if (last_idx >= hwsim_radio_idx-1)
goto done;
list_for_each_entry(data, &hwsim_radios, list) {
- if (data->idx < idx)
+ if (data->idx <= last_idx)
continue;
if (!net_eq(wiphy_net(data->hw->wiphy), sock_net(skb->sk)))
@@ -3328,14 +3333,25 @@ static int hwsim_dump_radio_nl(struct sk
if (res < 0)
break;
- idx = data->idx + 1;
+ last_idx = data->idx;
}
- cb->args[0] = idx;
+ cb->args[0] = last_idx;
+
+ /* list changed, but no new element sent, set interrupted flag */
+ if (skb->len == 0 && cb->prev_seq && cb->seq != cb->prev_seq) {
+ hdr = genlmsg_put(skb, NETLINK_CB(cb->skb).portid,
+ cb->nlh->nlmsg_seq, &hwsim_genl_family,
+ NLM_F_MULTI, HWSIM_CMD_GET_RADIO);
+ if (!hdr)
+ res = -EMSGSIZE;
+ genl_dump_check_consistent(cb, hdr);
+ genlmsg_end(skb, hdr);
+ }
done:
spin_unlock_bh(&hwsim_radio_lock);
- return skb->len;
+ return res ?: skb->len;
}
/* Generic Netlink operations array */
@@ -3393,6 +3409,7 @@ static void destroy_radio(struct work_st
struct mac80211_hwsim_data *data =
container_of(work, struct mac80211_hwsim_data, destroy_work);
+ hwsim_radios_generation++;
mac80211_hwsim_del_radio(data, wiphy_name(data->hw->wiphy), NULL);
}