From aac6af5534fade2b18682a0b9efad1a6c04c34c6 Mon Sep 17 00:00:00 2001 From: Yogesh Ashok Powar Date: Wed, 27 Apr 2011 18:40:29 +0530 Subject: [PATCH] mac80211: Skip tailroom reservation for full HW-crypto devices In xmit path, devices that do full hardware crypto (including TKIP MMIC) need no tailroom. For such devices, tailroom reservation can be skipped if all the keys are programmed into the hardware (i.e software crypto is not used for any of the keys) and none of the keys wants software to generate Michael MIC. Signed-off-by: Yogesh Ashok Powar Signed-off-by: John W. Linville --- net/mac80211/ieee80211_i.h | 3 +++ net/mac80211/key.c | 19 +++++++++++++++++-- net/mac80211/tx.c | 7 +------ 3 files changed, 21 insertions(+), 8 deletions(-) diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h index 8d6d6e3..9e3b4f0 100644 --- a/net/mac80211/ieee80211_i.h +++ b/net/mac80211/ieee80211_i.h @@ -766,6 +766,9 @@ struct ieee80211_local { int tx_headroom; /* required headroom for hardware/radiotap */ + /* count for keys needing tailroom space allocation */ + int crypto_tx_tailroom_needed_cnt; + /* Tasklet and skb queue to process calls from IRQ mode. All frames * added to skb_queue will be processed, but frames in * skb_queue_unreliable may be dropped if the total length of these diff --git a/net/mac80211/key.c b/net/mac80211/key.c index af3c564..ca3c626 100644 --- a/net/mac80211/key.c +++ b/net/mac80211/key.c @@ -101,6 +101,10 @@ static int ieee80211_key_enable_hw_accel(struct ieee80211_key *key) if (!ret) { key->flags |= KEY_FLAG_UPLOADED_TO_HARDWARE; + + if (!(key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC)) + key->local->crypto_tx_tailroom_needed_cnt--; + return 0; } @@ -156,6 +160,9 @@ static void ieee80211_key_disable_hw_accel(struct ieee80211_key *key) key->conf.keyidx, sta ? sta->addr : bcast_addr, ret); key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE; + + if (!(key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC)) + key->local->crypto_tx_tailroom_needed_cnt++; } void ieee80211_key_removed(struct ieee80211_key_conf *key_conf) @@ -388,8 +395,10 @@ static void __ieee80211_key_destroy(struct ieee80211_key *key) ieee80211_aes_key_free(key->u.ccmp.tfm); if (key->conf.cipher == WLAN_CIPHER_SUITE_AES_CMAC) ieee80211_aes_cmac_key_free(key->u.aes_cmac.tfm); - if (key->local) + if (key->local) { ieee80211_debugfs_key_remove(key); + key->local->crypto_tx_tailroom_needed_cnt--; + } kfree(key); } @@ -451,6 +460,8 @@ int ieee80211_key_link(struct ieee80211_key *key, ieee80211_debugfs_key_add(key); + key->local->crypto_tx_tailroom_needed_cnt++; + ret = ieee80211_key_enable_hw_accel(key); mutex_unlock(&sdata->local->key_mtx); @@ -492,8 +503,12 @@ void ieee80211_enable_keys(struct ieee80211_sub_if_data *sdata) mutex_lock(&sdata->local->key_mtx); - list_for_each_entry(key, &sdata->key_list, list) + sdata->local->crypto_tx_tailroom_needed_cnt = 0; + + list_for_each_entry(key, &sdata->key_list, list) { + sdata->local->crypto_tx_tailroom_needed_cnt++; ieee80211_key_enable_hw_accel(key); + } mutex_unlock(&sdata->local->key_mtx); } diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c index a2043e4..e3e3aa1 100644 --- a/net/mac80211/tx.c +++ b/net/mac80211/tx.c @@ -1476,12 +1476,7 @@ static int ieee80211_skb_resize(struct ieee80211_local *local, { int tail_need = 0; - /* - * This could be optimised, devices that do full hardware - * crypto (including TKIP MMIC) need no tailroom... But we - * have no drivers for such devices currently. - */ - if (may_encrypt) { + if (may_encrypt && local->crypto_tx_tailroom_needed_cnt) { tail_need = IEEE80211_ENCRYPT_TAILROOM; tail_need -= skb_tailroom(skb); tail_need = max_t(int, tail_need, 0); -- 2.7.4