From 34e895075e21be3e21e71d6317440d1ee7969ad0 Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Wed, 3 Feb 2010 13:59:58 +0100 Subject: mac80211: allow station add/remove to sleep Many drivers would like to sleep during station addition and removal, and currently have a high complexity there from not being able to. This introduces two new callbacks sta_add() and sta_remove() that drivers can implement instead of using sta_notify() and that can sleep, and the new sta_add() callback is also allowed to fail. The reason we didn't do this previously is that the IBSS code wants to insert stations from the RX path, which is a tasklet, so cannot sleep. This patch will keep the station allocation in that path, but moves adding the station to the driver out of line. Since the addition can now fail, we can have IBSS peer structs the driver rejected -- in that case we still talk to the station but never tell the driver about it in the control.sta pointer. If there will ever be a driver that has a low limit on the number of stations and that cannot talk to any stations that are not known to it, we need to do come up with a new strategy of handling larger IBSSs, maybe quicker expiry or rejecting peers. Signed-off-by: Johannes Berg Signed-off-by: John W. Linville --- net/mac80211/mesh_plink.c | 17 +++++++++-------- 1 file changed, 9 insertions(+), 8 deletions(-) (limited to 'net/mac80211/mesh_plink.c') diff --git a/net/mac80211/mesh_plink.c b/net/mac80211/mesh_plink.c index 7985e5150898..bc4e20e57ff5 100644 --- a/net/mac80211/mesh_plink.c +++ b/net/mac80211/mesh_plink.c @@ -102,7 +102,7 @@ static struct sta_info *mesh_plink_alloc(struct ieee80211_sub_if_data *sdata, if (local->num_sta >= MESH_MAX_PLINKS) return NULL; - sta = sta_info_alloc(sdata, hw_addr, GFP_ATOMIC); + sta = sta_info_alloc(sdata, hw_addr, GFP_KERNEL); if (!sta) return NULL; @@ -236,12 +236,12 @@ void mesh_neighbour_update(u8 *hw_addr, u32 rates, struct ieee80211_sub_if_data sta = sta_info_get(sdata, hw_addr); if (!sta) { + rcu_read_unlock(); + sta = mesh_plink_alloc(sdata, hw_addr, rates); - if (!sta) { - rcu_read_unlock(); + if (!sta) return; - } - if (sta_info_insert(sta)) { + if (sta_info_insert_rcu(sta)) { rcu_read_unlock(); return; } @@ -485,9 +485,11 @@ void mesh_rx_plink_frame(struct ieee80211_sub_if_data *sdata, struct ieee80211_m } else if (!sta) { /* ftype == PLINK_OPEN */ u32 rates; + + rcu_read_unlock(); + if (!mesh_plink_free_count(sdata)) { mpl_dbg("Mesh plink error: no more free plinks\n"); - rcu_read_unlock(); return; } @@ -495,10 +497,9 @@ void mesh_rx_plink_frame(struct ieee80211_sub_if_data *sdata, struct ieee80211_m sta = mesh_plink_alloc(sdata, mgmt->sa, rates); if (!sta) { mpl_dbg("Mesh plink error: plink table full\n"); - rcu_read_unlock(); return; } - if (sta_info_insert(sta)) { + if (sta_info_insert_rcu(sta)) { rcu_read_unlock(); return; } -- cgit v1.2.3-59-g8ed1b