From 9720bb3ab0b80659c63ed337eab66104a4156db0 Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Tue, 21 Jun 2011 09:45:33 +0200 Subject: [PATCH] nl80211: use netlink consistent dump feature for BSS dumps Use the new consistent dump feature from (generic) netlink to advertise when dumps are incomplete. Readers may note that this does not initialize the rdev->bss_generation counter to a non-zero value. This is still OK since the value is modified only under spinlock when the list is modified. Since the dump code holds the spinlock, the value will either be > 0 already, or the list will still be empty in which case a consistent dump will actually be made (and be empty). Signed-off-by: Johannes Berg Signed-off-by: John W. Linville --- net/wireless/nl80211.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c index 10823e2b60ce..aed6d2ad4c90 100644 --- a/net/wireless/nl80211.c +++ b/net/wireless/nl80211.c @@ -3620,7 +3620,8 @@ static int nl80211_stop_sched_scan(struct sk_buff *skb, return __cfg80211_stop_sched_scan(rdev, false); } -static int nl80211_send_bss(struct sk_buff *msg, u32 pid, u32 seq, int flags, +static int nl80211_send_bss(struct sk_buff *msg, struct netlink_callback *cb, + u32 seq, int flags, struct cfg80211_registered_device *rdev, struct wireless_dev *wdev, struct cfg80211_internal_bss *intbss) @@ -3632,11 +3633,13 @@ static int nl80211_send_bss(struct sk_buff *msg, u32 pid, u32 seq, int flags, ASSERT_WDEV_LOCK(wdev); - hdr = nl80211hdr_put(msg, pid, seq, flags, + hdr = nl80211hdr_put(msg, NETLINK_CB(cb->skb).pid, seq, flags, NL80211_CMD_NEW_SCAN_RESULTS); if (!hdr) return -1; + genl_dump_check_consistent(cb, hdr, &nl80211_fam); + NLA_PUT_U32(msg, NL80211_ATTR_GENERATION, rdev->bss_generation); NLA_PUT_U32(msg, NL80211_ATTR_IFINDEX, wdev->netdev->ifindex); @@ -3725,11 +3728,12 @@ static int nl80211_dump_scan(struct sk_buff *skb, spin_lock_bh(&rdev->bss_lock); cfg80211_bss_expire(rdev); + cb->seq = rdev->bss_generation; + list_for_each_entry(scan, &rdev->bss_list, list) { if (++idx <= start) continue; - if (nl80211_send_bss(skb, - NETLINK_CB(cb->skb).pid, + if (nl80211_send_bss(skb, cb, cb->nlh->nlmsg_seq, NLM_F_MULTI, rdev, wdev, scan) < 0) { idx--; -- 2.20.1