From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from ug-out-1314.google.com ([66.249.92.174]:7052 "EHLO ug-out-1314.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751372AbXCJXZq (ORCPT ); Sat, 10 Mar 2007 18:25:46 -0500 Received: by ug-out-1314.google.com with SMTP id 44so1772801uga for ; Sat, 10 Mar 2007 15:25:45 -0800 (PST) To: Michael Buesch Subject: Re: [PATCH v3] d80211: Add software sequence support Date: Sun, 11 Mar 2007 00:25:30 +0100 Cc: John Linville , Jiri Benc , Johannes Berg , linux-wireless@vger.kernel.org, Michael Wu , Jouni Malinen References: <200702141423.27823.IvDoorn@gmail.com> <200703102021.40041.IvDoorn@gmail.com> <200703102032.36463.mb@bu3sch.de> In-Reply-To: <200703102032.36463.mb@bu3sch.de> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Message-Id: <200703110025.30400.IvDoorn@gmail.com> From: Ivo van Doorn Sender: linux-wireless-owner@vger.kernel.org List-ID: On Saturday 10 March 2007 20:32, Michael Buesch wrote: > On Saturday 10 March 2007 20:21, Ivo van Doorn wrote: > > Most hardware can keep track of sequence numbers themselves, > > unfortunately *most* doesn't cover all devices. ;) > > This patch will keep track of the (per-bss) sequence number > > if the flag IEEE80211_HW_SOFTWARE_SEQUENCE has been set. > > The question has been asked (by Jouni), but I didn't see > a good answer (maybe I missed it). > Why is this a flag at all? The sequence counter is such a > trivial thing that having an extra conditional is just _more_ > overhead. Why not simply calculate the seq all the time and > let hardware override it, if it has the capability to do so? > Calculation of the seq is cheap. No need to bloat code. It would also safe me a patch for rt2400pci and rt2500pci as well. ;) Well if nobody objects against setting the sequence number always, then below patch would be sufficient. :) Signed-off-by: Ivo van Doorn --- diff --git a/net/mac80211/ieee80211.c b/net/mac80211/ieee80211.c index 577dbe3..05a0929 100644 --- a/net/mac80211/ieee80211.c +++ b/net/mac80211/ieee80211.c @@ -54,6 +54,20 @@ static u8 * ieee80211_get_bssid(struct ieee80211_hdr *hdr, size_t len); static int ieee80211_mgmt_start_xmit(struct sk_buff *skb, struct net_device *dev); +static void ieee80211_include_sequence(struct ieee80211_sub_if_data *sdata, + struct ieee80211_hdr *hdr) +{ + /* + * Set the sequence number for this frame. + */ + hdr->seq_ctrl = cpu_to_le16(sdata->sequence & IEEE80211_SCTL_SEQ); + + /* + * Increase the sequence number. + */ + sdata->sequence = (sdata->sequence + 0x10) & IEEE80211_SCTL_SEQ; +} + struct ieee80211_key_conf * ieee80211_key_data2conf(struct ieee80211_local *local, const struct ieee80211_key *data) @@ -445,6 +459,7 @@ ieee80211_tx_h_fragment(struct ieee80211_txrx_data *tx) size_t hdrlen, per_fragm, num_fragm, payload_len, left; struct sk_buff **frags, *first, *frag; int i; + u16 seq; u8 *pos; int frag_threshold = tx->local->fragmentation_threshold; @@ -463,6 +478,7 @@ ieee80211_tx_h_fragment(struct ieee80211_txrx_data *tx) goto fail; hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_MOREFRAGS); + seq = le16_to_cpu(hdr->seq_ctrl) & IEEE80211_SCTL_SEQ; pos = first->data + hdrlen + per_fragm; left = payload_len - per_fragm; for (i = 0; i < num_fragm - 1; i++) { @@ -490,7 +506,7 @@ ieee80211_tx_h_fragment(struct ieee80211_txrx_data *tx) memcpy(fhdr, first->data, hdrlen); if (i == num_fragm - 2) fhdr->frame_control &= cpu_to_le16(~IEEE80211_FCTL_MOREFRAGS); - fhdr->seq_ctrl = cpu_to_le16(i + 1); + fhdr->seq_ctrl = cpu_to_le16(seq + ((i + 1) & IEEE80211_SCTL_FRAG)); copylen = left > per_fragm ? per_fragm : left; memcpy(skb_put(frag, copylen), pos, copylen); @@ -900,6 +916,16 @@ ieee80211_tx_h_check_assoc(struct ieee80211_txrx_data *tx) return TXRX_CONTINUE; } +static ieee80211_txrx_result +ieee80211_tx_h_sequence(struct ieee80211_txrx_data *tx) +{ + struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data; + + if (ieee80211_get_hdrlen(le16_to_cpu(hdr->frame_control)) >= 24) + ieee80211_include_sequence(tx->sdata, hdr); + + return TXRX_CONTINUE; +} /* This function is called whenever the AP is about to exceed the maximum limit * of buffered frames for power saving STAs. This situation should not really @@ -1770,6 +1796,8 @@ struct sk_buff * ieee80211_beacon_get(struct ieee80211_hw *hw, int if_id, skb_reserve(skb, local->hw.extra_tx_headroom); memcpy(skb_put(skb, bh_len), b_head, bh_len); + ieee80211_include_sequence(sdata, (struct ieee80211_hdr *)skb->data); + ieee80211_beacon_add_tim(local, ap, skb); if (b_tail) { @@ -4381,6 +4409,7 @@ static ieee80211_rx_handler ieee80211_rx_handlers[] = static ieee80211_tx_handler ieee80211_tx_handlers[] = { ieee80211_tx_h_check_assoc, + ieee80211_tx_h_sequence, ieee80211_tx_h_ps_buf, ieee80211_tx_h_select_key, ieee80211_tx_h_michael_mic_add, diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h index 9df8ef0..4b7c427 100644 --- a/net/mac80211/ieee80211_i.h +++ b/net/mac80211/ieee80211_i.h @@ -317,6 +317,8 @@ struct ieee80211_sub_if_data { int ieee802_1x; /* IEEE 802.1X PAE - drop packet to/from unauthorized * port */ + u16 sequence; + /* Fragment table for host-based reassembly */ struct ieee80211_fragment_entry fragments[IEEE80211_FRAGMENT_MAX]; unsigned int fragment_next;