lk/linux-kernel-test
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

nl80211: add generation number to all dumps

Browse Source 
In order for userspace to be able to figure out whether
it obtained a consistent snapshot of data or not when
using netlink dumps, we need to have a generation number
in each dump message that indicates whether the list has
changed or not -- its value is arbitrary.

This patch adds such a number to all dumps, this needs
some mac80211 involvement to keep track of a generation
number to start with when adding/removing mesh paths or
stations.

The wiphy and netdev lists can be fully handled within
cfg80211, of course, but generation numbers need to be
stored there as well.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This commit is contained in:
Johannes Berg
2009-08-07 16:17:38 +02:00
committed by John W. Linville
parent f401a6f7ed
commit f5ea9120be
11 changed files with 67 additions and 15 deletions
Download Patch File Download Diff File Expand all files Collapse all files

31
net/wireless/nl80211.c
View File

@@ -408,6 +408,9 @@ static int nl80211_send_wiphy(struct sk_buff *msg, u32 pid, u32 seq, int flags,
NLA_PUT_U32(msg, NL80211_ATTR_WIPHY, dev->wiphy_idx);
NLA_PUT_STRING(msg, NL80211_ATTR_WIPHY_NAME, wiphy_name(&dev->wiphy));
NLA_PUT_U32(msg, NL80211_ATTR_GENERATION,
cfg80211_rdev_list_generation);
NLA_PUT_U8(msg, NL80211_ATTR_WIPHY_RETRY_SHORT,
dev->wiphy.retry_short);
NLA_PUT_U8(msg, NL80211_ATTR_WIPHY_RETRY_LONG,
@@ -825,6 +828,11 @@ static int nl80211_send_iface(struct sk_buff *msg, u32 pid, u32 seq, int flags,
NLA_PUT_U32(msg, NL80211_ATTR_WIPHY, rdev->wiphy_idx);
NLA_PUT_STRING(msg, NL80211_ATTR_IFNAME, dev->name);
NLA_PUT_U32(msg, NL80211_ATTR_IFTYPE, dev->ieee80211_ptr->iftype);
NLA_PUT_U32(msg, NL80211_ATTR_GENERATION,
rdev->devlist_generation ^
(cfg80211_rdev_list_generation << 2));
return genlmsg_end(msg, hdr);
nla_put_failure:
@@ -838,12 +846,12 @@ static int nl80211_dump_interface(struct sk_buff *skb, struct netlink_callback *
int if_idx = 0;
int wp_start = cb->args[0];
int if_start = cb->args[1];
struct cfg80211_registered_device *dev;
struct cfg80211_registered_device *rdev;
struct wireless_dev *wdev;
mutex_lock(&cfg80211_mutex);
list_for_each_entry(dev, &cfg80211_rdev_list, list) {
if (!net_eq(wiphy_net(&dev->wiphy), sock_net(skb->sk)))
list_for_each_entry(rdev, &cfg80211_rdev_list, list) {
if (!net_eq(wiphy_net(&rdev->wiphy), sock_net(skb->sk)))
continue;
if (wp_idx < wp_start) {
wp_idx++;
@@ -851,21 +859,21 @@ static int nl80211_dump_interface(struct sk_buff *skb, struct netlink_callback *
}
if_idx = 0;
mutex_lock(&dev->devlist_mtx);
list_for_each_entry(wdev, &dev->netdev_list, list) {
mutex_lock(&rdev->devlist_mtx);
list_for_each_entry(wdev, &rdev->netdev_list, list) {
if (if_idx < if_start) {
if_idx++;
continue;
}
if (nl80211_send_iface(skb, NETLINK_CB(cb->skb).pid,
cb->nlh->nlmsg_seq, NLM_F_MULTI,
dev, wdev->netdev) < 0) {
mutex_unlock(&dev->devlist_mtx);
rdev, wdev->netdev) < 0) {
mutex_unlock(&rdev->devlist_mtx);
goto out;
}
if_idx++;
}
mutex_unlock(&dev->devlist_mtx);
mutex_unlock(&rdev->devlist_mtx);
wp_idx++;
}
@@ -1616,6 +1624,8 @@ static int nl80211_send_station(struct sk_buff *msg, u32 pid, u32 seq,
NLA_PUT_U32(msg, NL80211_ATTR_IFINDEX, dev->ifindex);
NLA_PUT(msg, NL80211_ATTR_MAC, ETH_ALEN, mac_addr);
NLA_PUT_U32(msg, NL80211_ATTR_GENERATION, sinfo->generation);
sinfoattr = nla_nest_start(msg, NL80211_ATTR_STA_INFO);
if (!sinfoattr)
goto nla_put_failure;
@@ -2101,6 +2111,8 @@ static int nl80211_send_mpath(struct sk_buff *msg, u32 pid, u32 seq,
NLA_PUT(msg, NL80211_ATTR_MAC, ETH_ALEN, dst);
NLA_PUT(msg, NL80211_ATTR_MPATH_NEXT_HOP, ETH_ALEN, next_hop);
NLA_PUT_U32(msg, NL80211_ATTR_GENERATION, pinfo->generation);
pinfoattr = nla_nest_start(msg, NL80211_ATTR_MPATH_INFO);
if (!pinfoattr)
goto nla_put_failure;
@@ -3090,8 +3102,7 @@ static int nl80211_send_bss(struct sk_buff *msg, u32 pid, u32 seq, int flags,
if (!hdr)
return -1;
NLA_PUT_U32(msg, NL80211_ATTR_SCAN_GENERATION,
rdev->bss_generation);
NLA_PUT_U32(msg, NL80211_ATTR_GENERATION, rdev->bss_generation);
NLA_PUT_U32(msg, NL80211_ATTR_IFINDEX, wdev->netdev->ifindex);
bss = nla_nest_start(msg, NL80211_ATTR_BSS);