From: Daniel C Halperin Date: Thu, 13 Aug 2009 20:30:56 +0000 (-0700) Subject: iwlwifi: refactor packet reception code X-Git-Tag: v2.6.32-rc1~703^2~335^2~92 X-Git-Url: https://git.openpandora.org/cgi-bin/gitweb.cgi?p=pandora-kernel.git;a=commitdiff_plain;h=9f30e04e041cf9943940f71fd76094dd5a237018 iwlwifi: refactor packet reception code This patch fixes a number of issues in iwl_rx_reply_rx and iwl_pass_packet_to_mac80211. These issues stem from the complexities of managing two different types of packet commands for different hardware. - Unify code handling rx_phy_res in SKB or cached to eliminate redundancy and remove potential NULL pointer accesses - Replace magic number with proper constant - Optimize functions by moving early exit conditions before computation - Comment code and improve some variable names - Remove redundant computation in iwl_pass_packet_to_mac80211 by passing in the correct, already-computed arguments. Signed-off-by: Daniel C Halperin Signed-off-by: Reinette Chatre Signed-off-by: John W. Linville --- diff --git a/drivers/net/wireless/iwlwifi/iwl-commands.h b/drivers/net/wireless/iwlwifi/iwl-commands.h index 68d7719071f7..9398ad7e42b1 100644 --- a/drivers/net/wireless/iwlwifi/iwl-commands.h +++ b/drivers/net/wireless/iwlwifi/iwl-commands.h @@ -1156,6 +1156,7 @@ struct iwl_wep_cmd { #define RX_RES_PHY_FLAGS_SHORT_PREAMBLE_MSK cpu_to_le16(1 << 2) #define RX_RES_PHY_FLAGS_NARROW_BAND_MSK cpu_to_le16(1 << 3) #define RX_RES_PHY_FLAGS_ANTENNA_MSK cpu_to_le16(0xf0) +#define RX_RES_PHY_FLAGS_ANTENNA_POS 4 #define RX_RES_STATUS_SEC_TYPE_MSK (0x7 << 8) #define RX_RES_STATUS_SEC_TYPE_NONE (0x0 << 8) diff --git a/drivers/net/wireless/iwlwifi/iwl-rx.c b/drivers/net/wireless/iwlwifi/iwl-rx.c index 43b2fce4cbf0..092d3276175a 100644 --- a/drivers/net/wireless/iwlwifi/iwl-rx.c +++ b/drivers/net/wireless/iwlwifi/iwl-rx.c @@ -853,61 +853,12 @@ static u32 iwl_translate_rx_status(struct iwl_priv *priv, u32 decrypt_in) } static void iwl_pass_packet_to_mac80211(struct iwl_priv *priv, - int include_phy, - struct iwl_rx_mem_buffer *rxb, - struct ieee80211_rx_status *stats) + struct ieee80211_hdr *hdr, + u16 len, + u32 ampdu_status, + struct iwl_rx_mem_buffer *rxb, + struct ieee80211_rx_status *stats) { - struct iwl_rx_packet *pkt = (struct iwl_rx_packet *)rxb->skb->data; - struct iwl_rx_phy_res *rx_start = (include_phy) ? - (struct iwl_rx_phy_res *)&(pkt->u.raw[0]) : NULL; - struct ieee80211_hdr *hdr; - u16 len; - __le32 *rx_end; - unsigned int skblen; - u32 ampdu_status; - u32 ampdu_status_legacy; - - if (!include_phy && priv->last_phy_res[0]) - rx_start = (struct iwl_rx_phy_res *)&priv->last_phy_res[1]; - - if (!rx_start) { - IWL_ERR(priv, "MPDU frame without a PHY data\n"); - return; - } - if (include_phy) { - hdr = (struct ieee80211_hdr *)((u8 *) &rx_start[1] + - rx_start->cfg_phy_cnt); - - len = le16_to_cpu(rx_start->byte_count); - - rx_end = (__le32 *)((u8 *) &pkt->u.raw[0] + - sizeof(struct iwl_rx_phy_res) + - rx_start->cfg_phy_cnt + len); - - } else { - struct iwl4965_rx_mpdu_res_start *amsdu = - (struct iwl4965_rx_mpdu_res_start *)pkt->u.raw; - - hdr = (struct ieee80211_hdr *)(pkt->u.raw + - sizeof(struct iwl4965_rx_mpdu_res_start)); - len = le16_to_cpu(amsdu->byte_count); - rx_start->byte_count = amsdu->byte_count; - rx_end = (__le32 *) (((u8 *) hdr) + len); - } - - ampdu_status = le32_to_cpu(*rx_end); - skblen = ((u8 *) rx_end - (u8 *) &pkt->u.raw[0]) + sizeof(u32); - - if (!include_phy) { - /* New status scheme, need to translate */ - ampdu_status_legacy = ampdu_status; - ampdu_status = iwl_translate_rx_status(priv, ampdu_status); - } - - /* start from MAC */ - skb_reserve(rxb->skb, (void *)hdr - (void *)pkt); - skb_put(rxb->skb, len); /* end where data ends */ - /* We only process data packets if the interface is open */ if (unlikely(!priv->is_open)) { IWL_DEBUG_DROP_LIMIT(priv, @@ -915,13 +866,15 @@ static void iwl_pass_packet_to_mac80211(struct iwl_priv *priv, return; } - hdr = (struct ieee80211_hdr *)rxb->skb->data; - - /* in case of HW accelerated crypto and bad decryption, drop */ + /* In case of HW accelerated crypto and bad decryption, drop */ if (!priv->cfg->mod_params->sw_crypto && iwl_set_decrypted_flag(priv, hdr, ampdu_status, stats)) return; + /* Resize SKB from mac header to end of packet */ + skb_reserve(rxb->skb, (void *)hdr - (void *)rxb->skb->data); + skb_put(rxb->skb, len); + iwl_update_stats(priv, false, hdr->frame_control, len); memcpy(IEEE80211_SKB_RXCB(rxb->skb), stats, sizeof(*stats)); ieee80211_rx_irqsafe(priv->hw, rxb->skb); @@ -955,25 +908,66 @@ void iwl_rx_reply_rx(struct iwl_priv *priv, struct ieee80211_hdr *header; struct ieee80211_rx_status rx_status; struct iwl_rx_packet *pkt = (struct iwl_rx_packet *)rxb->skb->data; - /* Use phy data (Rx signal strength, etc.) contained within - * this rx packet for legacy frames, - * or phy data cached from REPLY_RX_PHY_CMD for HT frames. */ - int include_phy = (pkt->hdr.cmd == REPLY_RX); - struct iwl_rx_phy_res *rx_start = (include_phy) ? - (struct iwl_rx_phy_res *)&(pkt->u.raw[0]) : - (struct iwl_rx_phy_res *)&priv->last_phy_res[1]; - __le32 *rx_end; - unsigned int len = 0; + struct iwl_rx_phy_res *phy_res; + __le32 rx_pkt_status; + struct iwl4965_rx_mpdu_res_start *amsdu; + u32 len; + u32 ampdu_status; u16 fc; - u8 network_packet; - rx_status.mactime = le64_to_cpu(rx_start->timestamp); + /** + * REPLY_RX and REPLY_RX_MPDU_CMD are handled differently. + * REPLY_RX: physical layer info is in this buffer + * REPLY_RX_MPDU_CMD: physical layer info was sent in separate + * command and cached in priv->last_phy_res + * + * Here we set up local variables depending on which command is + * received. + */ + if (pkt->hdr.cmd == REPLY_RX) { + phy_res = (struct iwl_rx_phy_res *)pkt->u.raw; + header = (struct ieee80211_hdr *)(pkt->u.raw + sizeof(*phy_res) + + phy_res->cfg_phy_cnt); + + len = le16_to_cpu(phy_res->byte_count); + rx_pkt_status = *(__le32 *)(pkt->u.raw + sizeof(*phy_res) + + phy_res->cfg_phy_cnt + len); + ampdu_status = le32_to_cpu(rx_pkt_status); + } else { + if (!priv->last_phy_res[0]) { + IWL_ERR(priv, "MPDU frame without cached PHY data\n"); + return; + } + phy_res = (struct iwl_rx_phy_res *)&priv->last_phy_res[1]; + amsdu = (struct iwl4965_rx_mpdu_res_start *)pkt->u.raw; + header = (struct ieee80211_hdr *)(pkt->u.raw + sizeof(*amsdu)); + len = le16_to_cpu(amsdu->byte_count); + rx_pkt_status = *(__le32 *)(pkt->u.raw + sizeof(*amsdu) + len); + ampdu_status = iwl_translate_rx_status(priv, + le32_to_cpu(rx_pkt_status)); + } + + if ((unlikely(phy_res->cfg_phy_cnt > 20))) { + IWL_DEBUG_DROP(priv, "dsp size out of range [0,20]: %d/n", + phy_res->cfg_phy_cnt); + return; + } + + if (!(rx_pkt_status & RX_RES_STATUS_NO_CRC32_ERROR) || + !(rx_pkt_status & RX_RES_STATUS_NO_RXE_OVERFLOW)) { + IWL_DEBUG_RX(priv, "Bad CRC or FIFO: 0x%08X.\n", + le32_to_cpu(rx_pkt_status)); + return; + } + + /* rx_status carries information about the packet to mac80211 */ + rx_status.mactime = le64_to_cpu(phy_res->timestamp); rx_status.freq = - ieee80211_channel_to_frequency(le16_to_cpu(rx_start->channel)); - rx_status.band = (rx_start->phy_flags & RX_RES_PHY_FLAGS_BAND_24_MSK) ? + ieee80211_channel_to_frequency(le16_to_cpu(phy_res->channel)); + rx_status.band = (phy_res->phy_flags & RX_RES_PHY_FLAGS_BAND_24_MSK) ? IEEE80211_BAND_2GHZ : IEEE80211_BAND_5GHZ; rx_status.rate_idx = - iwl_hwrate_to_plcp_idx(le32_to_cpu(rx_start->rate_n_flags)); + iwl_hwrate_to_plcp_idx(le32_to_cpu(phy_res->rate_n_flags)); if (rx_status.band == IEEE80211_BAND_5GHZ) rx_status.rate_idx -= IWL_FIRST_OFDM_RATE; @@ -983,54 +977,10 @@ void iwl_rx_reply_rx(struct iwl_priv *priv, * this W/A doesn't propagate it to the mac80211 */ /*rx_status.flag |= RX_FLAG_TSFT;*/ - if ((unlikely(rx_start->cfg_phy_cnt > 20))) { - IWL_DEBUG_DROP(priv, "dsp size out of range [0,20]: %d/n", - rx_start->cfg_phy_cnt); - return; - } - - if (!include_phy) { - if (priv->last_phy_res[0]) - rx_start = (struct iwl_rx_phy_res *) - &priv->last_phy_res[1]; - else - rx_start = NULL; - } - - if (!rx_start) { - IWL_ERR(priv, "MPDU frame without a PHY data\n"); - return; - } - - if (include_phy) { - header = (struct ieee80211_hdr *)((u8 *) &rx_start[1] - + rx_start->cfg_phy_cnt); - - len = le16_to_cpu(rx_start->byte_count); - rx_end = (__le32 *)(pkt->u.raw + rx_start->cfg_phy_cnt + - sizeof(struct iwl_rx_phy_res) + len); - } else { - struct iwl4965_rx_mpdu_res_start *amsdu = - (struct iwl4965_rx_mpdu_res_start *)pkt->u.raw; - - header = (void *)(pkt->u.raw + - sizeof(struct iwl4965_rx_mpdu_res_start)); - len = le16_to_cpu(amsdu->byte_count); - rx_end = (__le32 *) (pkt->u.raw + - sizeof(struct iwl4965_rx_mpdu_res_start) + len); - } - - if (!(*rx_end & RX_RES_STATUS_NO_CRC32_ERROR) || - !(*rx_end & RX_RES_STATUS_NO_RXE_OVERFLOW)) { - IWL_DEBUG_RX(priv, "Bad CRC or FIFO: 0x%08X.\n", - le32_to_cpu(*rx_end)); - return; - } - - priv->ucode_beacon_time = le32_to_cpu(rx_start->beacon_time_stamp); + priv->ucode_beacon_time = le32_to_cpu(phy_res->beacon_time_stamp); /* Find max signal strength (dBm) among 3 antenna/receiver chains */ - rx_status.signal = iwl_calc_rssi(priv, rx_start); + rx_status.signal = iwl_calc_rssi(priv, phy_res); /* Meaningful noise values are available only from beacon statistics, * which are gathered only when associated, and indicate noise @@ -1050,10 +1000,10 @@ void iwl_rx_reply_rx(struct iwl_priv *priv, if (!iwl_is_associated(priv)) priv->last_rx_noise = IWL_NOISE_MEAS_NOT_AVAILABLE; - /* Set "1" to report good data frames in groups of 100 */ #ifdef CONFIG_IWLWIFI_DEBUG + /* Set "1" to report good data frames in groups of 100 */ if (unlikely(iwl_get_debug_level(priv) & IWL_DL_RX)) - iwl_dbg_report_frame(priv, rx_start, len, header, 1); + iwl_dbg_report_frame(priv, phy_res, len, header, 1); #endif iwl_dbg_log_rx_data_frame(priv, len, header); IWL_DEBUG_STATS_LIMIT(priv, "Rssi %d, noise %d, qual %d, TSF %llu\n", @@ -1073,18 +1023,18 @@ void iwl_rx_reply_rx(struct iwl_priv *priv, * new 802.11n radiotap field "RX chains" that is defined * as a bitmask. */ - rx_status.antenna = le16_to_cpu(rx_start->phy_flags & - RX_RES_PHY_FLAGS_ANTENNA_MSK) >> 4; + rx_status.antenna = + le16_to_cpu(phy_res->phy_flags & RX_RES_PHY_FLAGS_ANTENNA_MSK) + >> RX_RES_PHY_FLAGS_ANTENNA_POS; /* set the preamble flag if appropriate */ - if (rx_start->phy_flags & RX_RES_PHY_FLAGS_SHORT_PREAMBLE_MSK) + if (phy_res->phy_flags & RX_RES_PHY_FLAGS_SHORT_PREAMBLE_MSK) rx_status.flag |= RX_FLAG_SHORTPRE; - network_packet = iwl_is_network_packet(priv, header); - if (network_packet) { + if (iwl_is_network_packet(priv, header)) { priv->last_rx_rssi = rx_status.signal; priv->last_beacon_time = priv->ucode_beacon_time; - priv->last_tsf = le64_to_cpu(rx_start->timestamp); + priv->last_tsf = le64_to_cpu(phy_res->timestamp); } fc = le16_to_cpu(header->frame_control); @@ -1096,8 +1046,8 @@ void iwl_rx_reply_rx(struct iwl_priv *priv, header->addr2); /* fall through */ default: - iwl_pass_packet_to_mac80211(priv, include_phy, rxb, - &rx_status); + iwl_pass_packet_to_mac80211(priv, header, len, ampdu_status, + rxb, &rx_status); break; }