diff options
Diffstat (limited to 'drivers/net/wireless/ralink/rt2x00/rt2x00queue.c')
| -rw-r--r-- | drivers/net/wireless/ralink/rt2x00/rt2x00queue.c | 1287 |
1 files changed, 1287 insertions, 0 deletions
diff --git a/drivers/net/wireless/ralink/rt2x00/rt2x00queue.c b/drivers/net/wireless/ralink/rt2x00/rt2x00queue.c new file mode 100644 index 0000000..e1660b9 --- /dev/null +++ b/drivers/net/wireless/ralink/rt2x00/rt2x00queue.c @@ -0,0 +1,1287 @@ +/* + Copyright (C) 2010 Willow Garage <http://www.willowgarage.com> + Copyright (C) 2004 - 2010 Ivo van Doorn <IvDoorn@gmail.com> + Copyright (C) 2004 - 2009 Gertjan van Wingerde <gwingerde@gmail.com> + <http://rt2x00.serialmonkey.com> + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, see <http://www.gnu.org/licenses/>. + */ + +/* + Module: rt2x00lib + Abstract: rt2x00 queue specific routines. + */ + +#include <linux/slab.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/dma-mapping.h> + +#include "rt2x00.h" +#include "rt2x00lib.h" + +struct sk_buff *rt2x00queue_alloc_rxskb(struct queue_entry *entry, gfp_t gfp) +{ + struct data_queue *queue = entry->queue; + struct rt2x00_dev *rt2x00dev = queue->rt2x00dev; + struct sk_buff *skb; + struct skb_frame_desc *skbdesc; + unsigned int frame_size; + unsigned int head_size = 0; + unsigned int tail_size = 0; + + /* + * The frame size includes descriptor size, because the + * hardware directly receive the frame into the skbuffer. + */ + frame_size = queue->data_size + queue->desc_size + queue->winfo_size; + + /* + * The payload should be aligned to a 4-byte boundary, + * this means we need at least 3 bytes for moving the frame + * into the correct offset. + */ + head_size = 4; + + /* + * For IV/EIV/ICV assembly we must make sure there is + * at least 8 bytes bytes available in headroom for IV/EIV + * and 8 bytes for ICV data as tailroon. + */ + if (rt2x00_has_cap_hw_crypto(rt2x00dev)) { + head_size += 8; + tail_size += 8; + } + + /* + * Allocate skbuffer. + */ + skb = __dev_alloc_skb(frame_size + head_size + tail_size, gfp); + if (!skb) + return NULL; + + /* + * Make sure we not have a frame with the requested bytes + * available in the head and tail. + */ + skb_reserve(skb, head_size); + skb_put(skb, frame_size); + + /* + * Populate skbdesc. + */ + skbdesc = get_skb_frame_desc(skb); + memset(skbdesc, 0, sizeof(*skbdesc)); + + if (rt2x00_has_cap_flag(rt2x00dev, REQUIRE_DMA)) { + dma_addr_t skb_dma; + + skb_dma = dma_map_single(rt2x00dev->dev, skb->data, skb->len, + DMA_FROM_DEVICE); + if (unlikely(dma_mapping_error(rt2x00dev->dev, skb_dma))) { + dev_kfree_skb_any(skb); + return NULL; + } + + skbdesc->skb_dma = skb_dma; + skbdesc->flags |= SKBDESC_DMA_MAPPED_RX; + } + + return skb; +} + +int rt2x00queue_map_txskb(struct queue_entry *entry) +{ + struct device *dev = entry->queue->rt2x00dev->dev; + struct skb_frame_desc *skbdesc = get_skb_frame_desc(entry->skb); + + skbdesc->skb_dma = + dma_map_single(dev, entry->skb->data, entry->skb->len, DMA_TO_DEVICE); + + if (unlikely(dma_mapping_error(dev, skbdesc->skb_dma))) + return -ENOMEM; + + skbdesc->flags |= SKBDESC_DMA_MAPPED_TX; + return 0; +} +EXPORT_SYMBOL_GPL(rt2x00queue_map_txskb); + +void rt2x00queue_unmap_skb(struct queue_entry *entry) +{ + struct device *dev = entry->queue->rt2x00dev->dev; + struct skb_frame_desc *skbdesc = get_skb_frame_desc(entry->skb); + + if (skbdesc->flags & SKBDESC_DMA_MAPPED_RX) { + dma_unmap_single(dev, skbdesc->skb_dma, entry->skb->len, + DMA_FROM_DEVICE); + skbdesc->flags &= ~SKBDESC_DMA_MAPPED_RX; + } else if (skbdesc->flags & SKBDESC_DMA_MAPPED_TX) { + dma_unmap_single(dev, skbdesc->skb_dma, entry->skb->len, + DMA_TO_DEVICE); + skbdesc->flags &= ~SKBDESC_DMA_MAPPED_TX; + } +} +EXPORT_SYMBOL_GPL(rt2x00queue_unmap_skb); + +void rt2x00queue_free_skb(struct queue_entry *entry) +{ + if (!entry->skb) + return; + + rt2x00queue_unmap_skb(entry); + dev_kfree_skb_any(entry->skb); + entry->skb = NULL; +} + +void rt2x00queue_align_frame(struct sk_buff *skb) +{ + unsigned int frame_length = skb->len; + unsigned int align = ALIGN_SIZE(skb, 0); + + if (!align) + return; + + skb_push(skb, align); + memmove(skb->data, skb->data + align, frame_length); + skb_trim(skb, frame_length); +} + +/* + * H/W needs L2 padding between the header and the paylod if header size + * is not 4 bytes aligned. + */ +void rt2x00queue_insert_l2pad(struct sk_buff *skb, unsigned int hdr_len) +{ + unsigned int l2pad = (skb->len > hdr_len) ? L2PAD_SIZE(hdr_len) : 0; + + if (!l2pad) + return; + + skb_push(skb, l2pad); + memmove(skb->data, skb->data + l2pad, hdr_len); +} + +void rt2x00queue_remove_l2pad(struct sk_buff *skb, unsigned int hdr_len) +{ + unsigned int l2pad = (skb->len > hdr_len) ? L2PAD_SIZE(hdr_len) : 0; + + if (!l2pad) + return; + + memmove(skb->data + l2pad, skb->data, hdr_len); + skb_pull(skb, l2pad); +} + +static void rt2x00queue_create_tx_descriptor_seq(struct rt2x00_dev *rt2x00dev, + struct sk_buff *skb, + struct txentry_desc *txdesc) +{ + struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb); + struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; + struct rt2x00_intf *intf = vif_to_intf(tx_info->control.vif); + u16 seqno; + + if (!(tx_info->flags & IEEE80211_TX_CTL_ASSIGN_SEQ)) + return; + + __set_bit(ENTRY_TXD_GENERATE_SEQ, &txdesc->flags); + + if (!rt2x00_has_cap_flag(rt2x00dev, REQUIRE_SW_SEQNO)) { + /* + * rt2800 has a H/W (or F/W) bug, device incorrectly increase + * seqno on retransmited data (non-QOS) frames. To workaround + * the problem let's generate seqno in software if QOS is + * disabled. + */ + if (test_bit(CONFIG_QOS_DISABLED, &rt2x00dev->flags)) + __clear_bit(ENTRY_TXD_GENERATE_SEQ, &txdesc->flags); + else + /* H/W will generate sequence number */ + return; + } + + /* + * The hardware is not able to insert a sequence number. Assign a + * software generated one here. + * + * This is wrong because beacons are not getting sequence + * numbers assigned properly. + * + * A secondary problem exists for drivers that cannot toggle + * sequence counting per-frame, since those will override the + * sequence counter given by mac80211. + */ + if (test_bit(ENTRY_TXD_FIRST_FRAGMENT, &txdesc->flags)) + seqno = atomic_add_return(0x10, &intf->seqno); + else + seqno = atomic_read(&intf->seqno); + + hdr->seq_ctrl &= cpu_to_le16(IEEE80211_SCTL_FRAG); + hdr->seq_ctrl |= cpu_to_le16(seqno); +} + +static void rt2x00queue_create_tx_descriptor_plcp(struct rt2x00_dev *rt2x00dev, + struct sk_buff *skb, + struct txentry_desc *txdesc, + const struct rt2x00_rate *hwrate) +{ + struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb); + struct ieee80211_tx_rate *txrate = &tx_info->control.rates[0]; + unsigned int data_length; + unsigned int duration; + unsigned int residual; + + /* + * Determine with what IFS priority this frame should be send. + * Set ifs to IFS_SIFS when the this is not the first fragment, + * or this fragment came after RTS/CTS. + */ + if (test_bit(ENTRY_TXD_FIRST_FRAGMENT, &txdesc->flags)) + txdesc->u.plcp.ifs = IFS_BACKOFF; + else + txdesc->u.plcp.ifs = IFS_SIFS; + + /* Data length + CRC + Crypto overhead (IV/EIV/ICV/MIC) */ + data_length = skb->len + 4; + data_length += rt2x00crypto_tx_overhead(rt2x00dev, skb); + + /* + * PLCP setup + * Length calculation depends on OFDM/CCK rate. + */ + txdesc->u.plcp.signal = hwrate->plcp; + txdesc->u.plcp.service = 0x04; + + if (hwrate->flags & DEV_RATE_OFDM) { + txdesc->u.plcp.length_high = (data_length >> 6) & 0x3f; + txdesc->u.plcp.length_low = data_length & 0x3f; + } else { + /* + * Convert length to microseconds. + */ + residual = GET_DURATION_RES(data_length, hwrate->bitrate); + duration = GET_DURATION(data_length, hwrate->bitrate); + + if (residual != 0) { + duration++; + + /* + * Check if we need to set the Length Extension + */ + if (hwrate->bitrate == 110 && residual <= 30) + txdesc->u.plcp.service |= 0x80; + } + + txdesc->u.plcp.length_high = (duration >> 8) & 0xff; + txdesc->u.plcp.length_low = duration & 0xff; + + /* + * When preamble is enabled we should set the + * preamble bit for the signal. + */ + if (txrate->flags & IEEE80211_TX_RC_USE_SHORT_PREAMBLE) + txdesc->u.plcp.signal |= 0x08; + } +} + +static void rt2x00queue_create_tx_descriptor_ht(struct rt2x00_dev *rt2x00dev, + struct sk_buff *skb, + struct txentry_desc *txdesc, + struct ieee80211_sta *sta, + const struct rt2x00_rate *hwrate) +{ + struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb); + struct ieee80211_tx_rate *txrate = &tx_info->control.rates[0]; + struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; + struct rt2x00_sta *sta_priv = NULL; + u8 density = 0; + + if (sta) { + sta_priv = sta_to_rt2x00_sta(sta); + txdesc->u.ht.wcid = sta_priv->wcid; + density = sta->ht_cap.ampdu_density; + } + + /* + * If IEEE80211_TX_RC_MCS is set txrate->idx just contains the + * mcs rate to be used + */ + if (txrate->flags & IEEE80211_TX_RC_MCS) { + txdesc->u.ht.mcs = txrate->idx; + + /* + * MIMO PS should be set to 1 for STA's using dynamic SM PS + * when using more then one tx stream (>MCS7). + */ + if (sta && txdesc->u.ht.mcs > 7 && + sta->smps_mode == IEEE80211_SMPS_DYNAMIC) + __set_bit(ENTRY_TXD_HT_MIMO_PS, &txdesc->flags); + } else { + txdesc->u.ht.mcs = rt2x00_get_rate_mcs(hwrate->mcs); + if (txrate->flags & IEEE80211_TX_RC_USE_SHORT_PREAMBLE) + txdesc->u.ht.mcs |= 0x08; + } + + if (test_bit(CONFIG_HT_DISABLED, &rt2x00dev->flags)) { + if (!(tx_info->flags & IEEE80211_TX_CTL_FIRST_FRAGMENT)) + txdesc->u.ht.txop = TXOP_SIFS; + else + txdesc->u.ht.txop = TXOP_BACKOFF; + + /* Left zero on all other settings. */ + return; + } + + /* + * Only one STBC stream is supported for now. + */ + if (tx_info->flags & IEEE80211_TX_CTL_STBC) + txdesc->u.ht.stbc = 1; + + /* + * This frame is eligible for an AMPDU, however, don't aggregate + * frames that are intended to probe a specific tx rate. + */ + if (tx_info->flags & IEEE80211_TX_CTL_AMPDU && + !(tx_info->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE)) { + __set_bit(ENTRY_TXD_HT_AMPDU, &txdesc->flags); + txdesc->u.ht.mpdu_density = density; + txdesc->u.ht.ba_size = 7; /* FIXME: What value is needed? */ + } + + /* + * Set 40Mhz mode if necessary (for legacy rates this will + * duplicate the frame to both channels). + */ + if (txrate->flags & IEEE80211_TX_RC_40_MHZ_WIDTH || + txrate->flags & IEEE80211_TX_RC_DUP_DATA) + __set_bit(ENTRY_TXD_HT_BW_40, &txdesc->flags); + if (txrate->flags & IEEE80211_TX_RC_SHORT_GI) + __set_bit(ENTRY_TXD_HT_SHORT_GI, &txdesc->flags); + + /* + * Determine IFS values + * - Use TXOP_BACKOFF for management frames except beacons + * - Use TXOP_SIFS for fragment bursts + * - Use TXOP_HTTXOP for everything else + * + * Note: rt2800 devices won't use CTS protection (if used) + * for frames not transmitted with TXOP_HTTXOP + */ + if (ieee80211_is_mgmt(hdr->frame_control) && + !ieee80211_is_beacon(hdr->frame_control)) + txdesc->u.ht.txop = TXOP_BACKOFF; + else if (!(tx_info->flags & IEEE80211_TX_CTL_FIRST_FRAGMENT)) + txdesc->u.ht.txop = TXOP_SIFS; + else + txdesc->u.ht.txop = TXOP_HTTXOP; +} + +static void rt2x00queue_create_tx_descriptor(struct rt2x00_dev *rt2x00dev, + struct sk_buff *skb, + struct txentry_desc *txdesc, + struct ieee80211_sta *sta) +{ + struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb); + struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; + struct ieee80211_tx_rate *txrate = &tx_info->control.rates[0]; + struct ieee80211_rate *rate; + const struct rt2x00_rate *hwrate = NULL; + + memset(txdesc, 0, sizeof(*txdesc)); + + /* + * Header and frame information. + */ + txdesc->length = skb->len; + txdesc->header_length = ieee80211_get_hdrlen_from_skb(skb); + + /* + * Check whether this frame is to be acked. + */ + if (!(tx_info->flags & IEEE80211_TX_CTL_NO_ACK)) + __set_bit(ENTRY_TXD_ACK, &txdesc->flags); + + /* + * Check if this is a RTS/CTS frame + */ + if (ieee80211_is_rts(hdr->frame_control) || + ieee80211_is_cts(hdr->frame_control)) { + __set_bit(ENTRY_TXD_BURST, &txdesc->flags); + if (ieee80211_is_rts(hdr->frame_control)) + __set_bit(ENTRY_TXD_RTS_FRAME, &txdesc->flags); + else + __set_bit(ENTRY_TXD_CTS_FRAME, &txdesc->flags); + if (tx_info->control.rts_cts_rate_idx >= 0) + rate = + ieee80211_get_rts_cts_rate(rt2x00dev->hw, tx_info); + } + + /* + * Determine retry information. + */ + txdesc->retry_limit = tx_info->control.rates[0].count - 1; + if (txdesc->retry_limit >= rt2x00dev->long_retry) + __set_bit(ENTRY_TXD_RETRY_MODE, &txdesc->flags); + + /* + * Check if more fragments are pending + */ + if (ieee80211_has_morefrags(hdr->frame_control)) { + __set_bit(ENTRY_TXD_BURST, &txdesc->flags); + __set_bit(ENTRY_TXD_MORE_FRAG, &txdesc->flags); + } + + /* + * Check if more frames (!= fragments) are pending + */ + if (tx_info->flags & IEEE80211_TX_CTL_MORE_FRAMES) + __set_bit(ENTRY_TXD_BURST, &txdesc->flags); + + /* + * Beacons and probe responses require the tsf timestamp + * to be inserted into the frame. + */ + if (ieee80211_is_beacon(hdr->frame_control) || + ieee80211_is_probe_resp(hdr->frame_control)) + __set_bit(ENTRY_TXD_REQ_TIMESTAMP, &txdesc->flags); + + if ((tx_info->flags & IEEE80211_TX_CTL_FIRST_FRAGMENT) && + !test_bit(ENTRY_TXD_RTS_FRAME, &txdesc->flags)) + __set_bit(ENTRY_TXD_FIRST_FRAGMENT, &txdesc->flags); + + /* + * Determine rate modulation. + */ + if (txrate->flags & IEEE80211_TX_RC_GREEN_FIELD) + txdesc->rate_mode = RATE_MODE_HT_GREENFIELD; + else if (txrate->flags & IEEE80211_TX_RC_MCS) + txdesc->rate_mode = RATE_MODE_HT_MIX; + else { + rate = ieee80211_get_tx_rate(rt2x00dev->hw, tx_info); + hwrate = rt2x00_get_rate(rate->hw_value); + if (hwrate->flags & DEV_RATE_OFDM) + txdesc->rate_mode = RATE_MODE_OFDM; + else + txdesc->rate_mode = RATE_MODE_CCK; + } + + /* + * Apply TX descriptor handling by components + */ + rt2x00crypto_create_tx_descriptor(rt2x00dev, skb, txdesc); + rt2x00queue_create_tx_descriptor_seq(rt2x00dev, skb, txdesc); + + if (rt2x00_has_cap_flag(rt2x00dev, REQUIRE_HT_TX_DESC)) + rt2x00queue_create_tx_descriptor_ht(rt2x00dev, skb, txdesc, + sta, hwrate); + else + rt2x00queue_create_tx_descriptor_plcp(rt2x00dev, skb, txdesc, + hwrate); +} + +static int rt2x00queue_write_tx_data(struct queue_entry *entry, + struct txentry_desc *txdesc) +{ + struct rt2x00_dev *rt2x00dev = entry->queue->rt2x00dev; + + /* + * This should not happen, we already checked the entry + * was ours. When the hardware disagrees there has been + * a queue corruption! + */ + if (unlikely(rt2x00dev->ops->lib->get_entry_state && + rt2x00dev->ops->lib->get_entry_state(entry))) { + rt2x00_err(rt2x00dev, + "Corrupt queue %d, accessing entry which is not ours\n" + "Please file bug report to %s\n", + entry->queue->qid, DRV_PROJECT); + return -EINVAL; + } + + /* + * Add the requested extra tx headroom in front of the skb. + */ + skb_push(entry->skb, rt2x00dev->extra_tx_headroom); + memset(entry->skb->data, 0, rt2x00dev->extra_tx_headroom); + + /* + * Call the driver's write_tx_data function, if it exists. + */ + if (rt2x00dev->ops->lib->write_tx_data) + rt2x00dev->ops->lib->write_tx_data(entry, txdesc); + + /* + * Map the skb to DMA. + */ + if (rt2x00_has_cap_flag(rt2x00dev, REQUIRE_DMA) && + rt2x00queue_map_txskb(entry)) + return -ENOMEM; + + return 0; +} + +static void rt2x00queue_write_tx_descriptor(struct queue_entry *entry, + struct txentry_desc *txdesc) +{ + struct data_queue *queue = entry->queue; + + queue->rt2x00dev->ops->lib->write_tx_desc(entry, txdesc); + + /* + * All processing on the frame has been completed, this means + * it is now ready to be dumped to userspace through debugfs. + */ + rt2x00debug_dump_frame(queue->rt2x00dev, DUMP_FRAME_TX, entry); +} + +static void rt2x00queue_kick_tx_queue(struct data_queue *queue, + struct txentry_desc *txdesc) +{ + /* + * Check if we need to kick the queue, there are however a few rules + * 1) Don't kick unless this is the last in frame in a burst. + * When the burst flag is set, this frame is always followed + * by another frame which in some way are related to eachother. + * This is true for fragments, RTS or CTS-to-self frames. + * 2) Rule 1 can be broken when the available entries + * in the queue are less then a certain threshold. + */ + if (rt2x00queue_threshold(queue) || + !test_bit(ENTRY_TXD_BURST, &txdesc->flags)) + queue->rt2x00dev->ops->lib->kick_queue(queue); +} + +static void rt2x00queue_bar_check(struct queue_entry *entry) +{ + struct rt2x00_dev *rt2x00dev = entry->queue->rt2x00dev; + struct ieee80211_bar *bar = (void *) (entry->skb->data + + rt2x00dev->extra_tx_headroom); + struct rt2x00_bar_list_entry *bar_entry; + + if (likely(!ieee80211_is_back_req(bar->frame_control))) + return; + + bar_entry = kmalloc(sizeof(*bar_entry), GFP_ATOMIC); + + /* + * If the alloc fails we still send the BAR out but just don't track + * it in our bar list. And as a result we will report it to mac80211 + * back as failed. + */ + if (!bar_entry) + return; + + bar_entry->entry = entry; + bar_entry->block_acked = 0; + + /* + * Copy the relevant parts of the 802.11 BAR into out check list + * such that we can use RCU for less-overhead in the RX path since + * sending BARs and processing the according BlockAck should be + * the exception. + */ + memcpy(bar_entry->ra, bar->ra, sizeof(bar->ra)); + memcpy(bar_entry->ta, bar->ta, sizeof(bar->ta)); + bar_entry->control = bar->control; + bar_entry->start_seq_num = bar->start_seq_num; + + /* + * Insert BAR into our BAR check list. + */ + spin_lock_bh(&rt2x00dev->bar_list_lock); + list_add_tail_rcu(&bar_entry->list, &rt2x00dev->bar_list); + spin_unlock_bh(&rt2x00dev->bar_list_lock); +} + +int rt2x00queue_write_tx_frame(struct data_queue *queue, struct sk_buff *skb, + struct ieee80211_sta *sta, bool local) +{ + struct ieee80211_tx_info *tx_info; + struct queue_entry *entry; + struct txentry_desc txdesc; + struct skb_frame_desc *skbdesc; + u8 rate_idx, rate_flags; + int ret = 0; + + /* + * Copy all TX descriptor information into txdesc, + * after that we are free to use the skb->cb array + * for our information. + */ + rt2x00queue_create_tx_descriptor(queue->rt2x00dev, skb, &txdesc, sta); + + /* + * All information is retrieved from the skb->cb array, + * now we should claim ownership of the driver part of that + * array, preserving the bitrate index and flags. + */ + tx_info = IEEE80211_SKB_CB(skb); + rate_idx = tx_info->control.rates[0].idx; + rate_flags = tx_info->control.rates[0].flags; + skbdesc = get_skb_frame_desc(skb); + memset(skbdesc, 0, sizeof(*skbdesc)); + skbdesc->tx_rate_idx = rate_idx; + skbdesc->tx_rate_flags = rate_flags; + + if (local) + skbdesc->flags |= SKBDESC_NOT_MAC80211; + + /* + * When hardware encryption is supported, and this frame + * is to be encrypted, we should strip the IV/EIV data from + * the frame so we can provide it to the driver separately. + */ + if (test_bit(ENTRY_TXD_ENCRYPT, &txdesc.flags) && + !test_bit(ENTRY_TXD_ENCRYPT_IV, &txdesc.flags)) { + if (rt2x00_has_cap_flag(queue->rt2x00dev, REQUIRE_COPY_IV)) + rt2x00crypto_tx_copy_iv(skb, &txdesc); + else + rt2x00crypto_tx_remove_iv(skb, &txdesc); + } + + /* + * When DMA allocation is required we should guarantee to the + * driver that the DMA is aligned to a 4-byte boundary. + * However some drivers require L2 padding to pad the payload + * rather then the header. This could be a requirement for + * PCI and USB devices, while header alignment only is valid + * for PCI devices. + */ + if (rt2x00_has_cap_flag(queue->rt2x00dev, REQUIRE_L2PAD)) + rt2x00queue_insert_l2pad(skb, txdesc.header_length); + else if (rt2x00_has_cap_flag(queue->rt2x00dev, REQUIRE_DMA)) + rt2x00queue_align_frame(skb); + + /* + * That function must be called with bh disabled. + */ + spin_lock(&queue->tx_lock); + + if (unlikely(rt2x00queue_full(queue))) { + rt2x00_err(queue->rt2x00dev, "Dropping frame due to full tx queue %d\n", + queue->qid); + ret = -ENOBUFS; + goto out; + } + + entry = rt2x00queue_get_entry(queue, Q_INDEX); + + if (unlikely(test_and_set_bit(ENTRY_OWNER_DEVICE_DATA, + &entry->flags))) { + rt2x00_err(queue->rt2x00dev, + "Arrived at non-free entry in the non-full queue %d\n" + "Please file bug report to %s\n", + queue->qid, DRV_PROJECT); + ret = -EINVAL; + goto out; + } + + entry->skb = skb; + + /* + * It could be possible that the queue was corrupted and this + * call failed. Since we always return NETDEV_TX_OK to mac80211, + * this frame will simply be dropped. + */ + if (unlikely(rt2x00queue_write_tx_data(entry, &txdesc))) { + clear_bit(ENTRY_OWNER_DEVICE_DATA, &entry->flags); + entry->skb = NULL; + ret = -EIO; + goto out; + } + + /* + * Put BlockAckReqs into our check list for driver BA processing. + */ + rt2x00queue_bar_check(entry); + + set_bit(ENTRY_DATA_PENDING, &entry->flags); + + rt2x00queue_index_inc(entry, Q_INDEX); + rt2x00queue_write_tx_descriptor(entry, &txdesc); + rt2x00queue_kick_tx_queue(queue, &txdesc); + +out: + spin_unlock(&queue->tx_lock); + return ret; +} + +int rt2x00queue_clear_beacon(struct rt2x00_dev *rt2x00dev, + struct ieee80211_vif *vif) +{ + struct rt2x00_intf *intf = vif_to_intf(vif); + + if (unlikely(!intf->beacon)) + return -ENOBUFS; + + /* + * Clean up the beacon skb. + */ + rt2x00queue_free_skb(intf->beacon); + + /* + * Clear beacon (single bssid devices don't need to clear the beacon + * since the beacon queue will get stopped anyway). + */ + if (rt2x00dev->ops->lib->clear_beacon) + rt2x00dev->ops->lib->clear_beacon(intf->beacon); + + return 0; +} + +int rt2x00queue_update_beacon(struct rt2x00_dev *rt2x00dev, + struct ieee80211_vif *vif) +{ + struct rt2x00_intf *intf = vif_to_intf(vif); + struct skb_frame_desc *skbdesc; + struct txentry_desc txdesc; + + if (unlikely(!intf->beacon)) + return -ENOBUFS; + + /* + * Clean up the beacon skb. + */ + rt2x00queue_free_skb(intf->beacon); + + intf->beacon->skb = ieee80211_beacon_get(rt2x00dev->hw, vif); + if (!intf->beacon->skb) + return -ENOMEM; + + /* + * Copy all TX descriptor information into txdesc, + * after that we are free to use the skb->cb array + * for our information. + */ + rt2x00queue_create_tx_descriptor(rt2x00dev, intf->beacon->skb, &txdesc, NULL); + + /* + * Fill in skb descriptor + */ + skbdesc = get_skb_frame_desc(intf->beacon->skb); + memset(skbdesc, 0, sizeof(*skbdesc)); + + /* + * Send beacon to hardware. + */ + rt2x00dev->ops->lib->write_beacon(intf->beacon, &txdesc); + + return 0; + +} + +bool rt2x00queue_for_each_entry(struct data_queue *queue, + enum queue_index start, + enum queue_index end, + void *data, + bool (*fn)(struct queue_entry *entry, + void *data)) +{ + unsigned long irqflags; + unsigned int index_start; + unsigned int index_end; + unsigned int i; + + if (unlikely(start >= Q_INDEX_MAX || end >= Q_INDEX_MAX)) { + rt2x00_err(queue->rt2x00dev, + "Entry requested from invalid index range (%d - %d)\n", + start, end); + return true; + } + + /* + * Only protect the range we are going to loop over, + * if during our loop a extra entry is set to pending + * it should not be kicked during this run, since it + * is part of another TX operation. + */ + spin_lock_irqsave(&queue->index_lock, irqflags); + index_start = queue->index[start]; + index_end = queue->index[end]; + spin_unlock_irqrestore(&queue->index_lock, irqflags); + + /* + * Start from the TX done pointer, this guarantees that we will + * send out all frames in the correct order. + */ + if (index_start < index_end) { + for (i = index_start; i < index_end; i++) { + if (fn(&queue->entries[i], data)) + return true; + } + } else { + for (i = index_start; i < queue->limit; i++) { + if (fn(&queue->entries[i], data)) + return true; + } + + for (i = 0; i < index_end; i++) { + if (fn(&queue->entries[i], data)) + return true; + } + } + + return false; +} +EXPORT_SYMBOL_GPL(rt2x00queue_for_each_entry); + +struct queue_entry *rt2x00queue_get_entry(struct data_queue *queue, + enum queue_index index) +{ + struct queue_entry *entry; + unsigned long irqflags; + + if (unlikely(index >= Q_INDEX_MAX)) { + rt2x00_err(queue->rt2x00dev, "Entry requested from invalid index type (%d)\n", + index); + return NULL; + } + + spin_lock_irqsave(&queue->index_lock, irqflags); + + entry = &queue->entries[queue->index[index]]; + + spin_unlock_irqrestore(&queue->index_lock, irqflags); + + return entry; +} +EXPORT_SYMBOL_GPL(rt2x00queue_get_entry); + +void rt2x00queue_index_inc(struct queue_entry *entry, enum queue_index index) +{ + struct data_queue *queue = entry->queue; + unsigned long irqflags; + + if (unlikely(index >= Q_INDEX_MAX)) { + rt2x00_err(queue->rt2x00dev, + "Index change on invalid index type (%d)\n", index); + return; + } + + spin_lock_irqsave(&queue->index_lock, irqflags); + + queue->index[index]++; + if (queue->index[index] >= queue->limit) + queue->index[index] = 0; + + entry->last_action = jiffies; + + if (index == Q_INDEX) { + queue->length++; + } else if (index == Q_INDEX_DONE) { + queue->length--; + queue->count++; + } + + spin_unlock_irqrestore(&queue->index_lock, irqflags); +} + +static void rt2x00queue_pause_queue_nocheck(struct data_queue *queue) +{ + switch (queue->qid) { + case QID_AC_VO: + case QID_AC_VI: + case QID_AC_BE: + case QID_AC_BK: + /* + * For TX queues, we have to disable the queue + * inside mac80211. + */ + ieee80211_stop_queue(queue->rt2x00dev->hw, queue->qid); + break; + default: + break; + } +} +void rt2x00queue_pause_queue(struct data_queue *queue) +{ + if (!test_bit(DEVICE_STATE_PRESENT, &queue->rt2x00dev->flags) || + !test_bit(QUEUE_STARTED, &queue->flags) || + test_and_set_bit(QUEUE_PAUSED, &queue->flags)) + return; + + rt2x00queue_pause_queue_nocheck(queue); +} +EXPORT_SYMBOL_GPL(rt2x00queue_pause_queue); + +void rt2x00queue_unpause_queue(struct data_queue *queue) +{ + if (!test_bit(DEVICE_STATE_PRESENT, &queue->rt2x00dev->flags) || + !test_bit(QUEUE_STARTED, &queue->flags) || + !test_and_clear_bit(QUEUE_PAUSED, &queue->flags)) + return; + + switch (queue->qid) { + case QID_AC_VO: + case QID_AC_VI: + case QID_AC_BE: + case QID_AC_BK: + /* + * For TX queues, we have to enable the queue + * inside mac80211. + */ + ieee80211_wake_queue(queue->rt2x00dev->hw, queue->qid); + break; + case QID_RX: + /* + * For RX we need to kick the queue now in order to + * receive frames. + */ + queue->rt2x00dev->ops->lib->kick_queue(queue); + default: + break; + } +} +EXPORT_SYMBOL_GPL(rt2x00queue_unpause_queue); + +void rt2x00queue_start_queue(struct data_queue *queue) +{ + mutex_lock(&queue->status_lock); + + if (!test_bit(DEVICE_STATE_PRESENT, &queue->rt2x00dev->flags) || + test_and_set_bit(QUEUE_STARTED, &queue->flags)) { + mutex_unlock(&queue->status_lock); + return; + } + + set_bit(QUEUE_PAUSED, &queue->flags); + + queue->rt2x00dev->ops->lib->start_queue(queue); + + rt2x00queue_unpause_queue(queue); + + mutex_unlock(&queue->status_lock); +} +EXPORT_SYMBOL_GPL(rt2x00queue_start_queue); + +void rt2x00queue_stop_queue(struct data_queue *queue) +{ + mutex_lock(&queue->status_lock); + + if (!test_and_clear_bit(QUEUE_STARTED, &queue->flags)) { + mutex_unlock(&queue->status_lock); + return; + } + + rt2x00queue_pause_queue_nocheck(queue); + + queue->rt2x00dev->ops->lib->stop_queue(queue); + + mutex_unlock(&queue->status_lock); +} +EXPORT_SYMBOL_GPL(rt2x00queue_stop_queue); + +void rt2x00queue_flush_queue(struct data_queue *queue, bool drop) +{ + bool tx_queue = + (queue->qid == QID_AC_VO) || + (queue->qid == QID_AC_VI) || + (queue->qid == QID_AC_BE) || + (queue->qid == QID_AC_BK); + + + /* + * If we are not supposed to drop any pending + * frames, this means we must force a start (=kick) + * to the queue to make sure the hardware will + * start transmitting. + */ + if (!drop && tx_queue) + queue->rt2x00dev->ops->lib->kick_queue(queue); + + /* + * Check if driver supports flushing, if that is the case we can + * defer the flushing to the driver. Otherwise we must use the + * alternative which just waits for the queue to become empty. + */ + if (likely(queue->rt2x00dev->ops->lib->flush_queue)) + queue->rt2x00dev->ops->lib->flush_queue(queue, drop); + + /* + * The queue flush has failed... + */ + if (unlikely(!rt2x00queue_empty(queue))) + rt2x00_warn(queue->rt2x00dev, "Queue %d failed to flush\n", + queue->qid); +} +EXPORT_SYMBOL_GPL(rt2x00queue_flush_queue); + +void rt2x00queue_start_queues(struct rt2x00_dev *rt2x00dev) +{ + struct data_queue *queue; + + /* + * rt2x00queue_start_queue will call ieee80211_wake_queue + * for each queue after is has been properly initialized. + */ + tx_queue_for_each(rt2x00dev, queue) + rt2x00queue_start_queue(queue); + + rt2x00queue_start_queue(rt2x00dev->rx); +} +EXPORT_SYMBOL_GPL(rt2x00queue_start_queues); + +void rt2x00queue_stop_queues(struct rt2x00_dev *rt2x00dev) +{ + struct data_queue *queue; + + /* + * rt2x00queue_stop_queue will call ieee80211_stop_queue + * as well, but we are completely shutting doing everything + * now, so it is much safer to stop all TX queues at once, + * and use rt2x00queue_stop_queue for cleaning up. + */ + ieee80211_stop_queues(rt2x00dev->hw); + + tx_queue_for_each(rt2x00dev, queue) + rt2x00queue_stop_queue(queue); + + rt2x00queue_stop_queue(rt2x00dev->rx); +} +EXPORT_SYMBOL_GPL(rt2x00queue_stop_queues); + +void rt2x00queue_flush_queues(struct rt2x00_dev *rt2x00dev, bool drop) +{ + struct data_queue *queue; + + tx_queue_for_each(rt2x00dev, queue) + rt2x00queue_flush_queue(queue, drop); + + rt2x00queue_flush_queue(rt2x00dev->rx, drop); +} +EXPORT_SYMBOL_GPL(rt2x00queue_flush_queues); + +static void rt2x00queue_reset(struct data_queue *queue) +{ + unsigned long irqflags; + unsigned int i; + + spin_lock_irqsave(&queue->index_lock, irqflags); + + queue->count = 0; + queue->length = 0; + + for (i = 0; i < Q_INDEX_MAX; i++) + queue->index[i] = 0; + + spin_unlock_irqrestore(&queue->index_lock, irqflags); +} + +void rt2x00queue_init_queues(struct rt2x00_dev *rt2x00dev) +{ + struct data_queue *queue; + unsigned int i; + + queue_for_each(rt2x00dev, queue) { + rt2x00queue_reset(queue); + + for (i = 0; i < queue->limit; i++) + rt2x00dev->ops->lib->clear_entry(&queue->entries[i]); + } +} + +static int rt2x00queue_alloc_entries(struct data_queue *queue) +{ + struct queue_entry *entries; + unsigned int entry_size; + unsigned int i; + + rt2x00queue_reset(queue); + + /* + * Allocate all queue entries. + */ + entry_size = sizeof(*entries) + queue->priv_size; + entries = kcalloc(queue->limit, entry_size, GFP_KERNEL); + if (!entries) + return -ENOMEM; + +#define QUEUE_ENTRY_PRIV_OFFSET(__base, __index, __limit, __esize, __psize) \ + (((char *)(__base)) + ((__limit) * (__esize)) + \ + ((__index) * (__psize))) + + for (i = 0; i < queue->limit; i++) { + entries[i].flags = 0; + entries[i].queue = queue; + entries[i].skb = NULL; + entries[i].entry_idx = i; + entries[i].priv_data = + QUEUE_ENTRY_PRIV_OFFSET(entries, i, queue->limit, + sizeof(*entries), queue->priv_size); + } + +#undef QUEUE_ENTRY_PRIV_OFFSET + + queue->entries = entries; + + return 0; +} + +static void rt2x00queue_free_skbs(struct data_queue *queue) +{ + unsigned int i; + + if (!queue->entries) + return; + + for (i = 0; i < queue->limit; i++) { + rt2x00queue_free_skb(&queue->entries[i]); + } +} + +static int rt2x00queue_alloc_rxskbs(struct data_queue *queue) +{ + unsigned int i; + struct sk_buff *skb; + + for (i = 0; i < queue->limit; i++) { + skb = rt2x00queue_alloc_rxskb(&queue->entries[i], GFP_KERNEL); + if (!skb) + return -ENOMEM; + queue->entries[i].skb = skb; + } + + return 0; +} + +int rt2x00queue_initialize(struct rt2x00_dev *rt2x00dev) +{ + struct data_queue *queue; + int status; + + status = rt2x00queue_alloc_entries(rt2x00dev->rx); + if (status) + goto exit; + + tx_queue_for_each(rt2x00dev, queue) { + status = rt2x00queue_alloc_entries(queue); + if (status) + goto exit; + } + + status = rt2x00queue_alloc_entries(rt2x00dev->bcn); + if (status) + goto exit; + + if (rt2x00_has_cap_flag(rt2x00dev, REQUIRE_ATIM_QUEUE)) { + status = rt2x00queue_alloc_entries(rt2x00dev->atim); + if (status) + goto exit; + } + + status = rt2x00queue_alloc_rxskbs(rt2x00dev->rx); + if (status) + goto exit; + + return 0; + +exit: + rt2x00_err(rt2x00dev, "Queue entries allocation failed\n"); + + rt2x00queue_uninitialize(rt2x00dev); + + return status; +} + +void rt2x00queue_uninitialize(struct rt2x00_dev *rt2x00dev) +{ + struct data_queue *queue; + + rt2x00queue_free_skbs(rt2x00dev->rx); + + queue_for_each(rt2x00dev, queue) { + kfree(queue->entries); + queue->entries = NULL; + } +} + +static void rt2x00queue_init(struct rt2x00_dev *rt2x00dev, + struct data_queue *queue, enum data_queue_qid qid) +{ + mutex_init(&queue->status_lock); + spin_lock_init(&queue->tx_lock); + spin_lock_init(&queue->index_lock); + + queue->rt2x00dev = rt2x00dev; + queue->qid = qid; + queue->txop = 0; + queue->aifs = 2; + queue->cw_min = 5; + queue->cw_max = 10; + + rt2x00dev->ops->queue_init(queue); + + queue->threshold = DIV_ROUND_UP(queue->limit, 10); +} + +int rt2x00queue_allocate(struct rt2x00_dev *rt2x00dev) +{ + struct data_queue *queue; + enum data_queue_qid qid; + unsigned int req_atim = + rt2x00_has_cap_flag(rt2x00dev, REQUIRE_ATIM_QUEUE); + + /* + * We need the following queues: + * RX: 1 + * TX: ops->tx_queues + * Beacon: 1 + * Atim: 1 (if required) + */ + rt2x00dev->data_queues = 2 + rt2x00dev->ops->tx_queues + req_atim; + + queue = kcalloc(rt2x00dev->data_queues, sizeof(*queue), GFP_KERNEL); + if (!queue) { + rt2x00_err(rt2x00dev, "Queue allocation failed\n"); + return -ENOMEM; + } + + /* + * Initialize pointers + */ + rt2x00dev->rx = queue; + rt2x00dev->tx = &queue[1]; + rt2x00dev->bcn = &queue[1 + rt2x00dev->ops->tx_queues]; + rt2x00dev->atim = req_atim ? &queue[2 + rt2x00dev->ops->tx_queues] : NULL; + + /* + * Initialize queue parameters. + * RX: qid = QID_RX + * TX: qid = QID_AC_VO + index + * TX: cw_min: 2^5 = 32. + * TX: cw_max: 2^10 = 1024. + * BCN: qid = QID_BEACON + * ATIM: qid = QID_ATIM + */ + rt2x00queue_init(rt2x00dev, rt2x00dev->rx, QID_RX); + + qid = QID_AC_VO; + tx_queue_for_each(rt2x00dev, queue) + rt2x00queue_init(rt2x00dev, queue, qid++); + + rt2x00queue_init(rt2x00dev, rt2x00dev->bcn, QID_BEACON); + if (req_atim) + rt2x00queue_init(rt2x00dev, rt2x00dev->atim, QID_ATIM); + + return 0; +} + +void rt2x00queue_free(struct rt2x00_dev *rt2x00dev) +{ + kfree(rt2x00dev->rx); + rt2x00dev->rx = NULL; + rt2x00dev->tx = NULL; + rt2x00dev->bcn = NULL; +} |