static void update_max_used_slots(struct b43_dmaring *ring,
int current_used_slots)
{
if (current_used_slots <= ring->max_used_slots)
return;
ring->max_used_slots = current_used_slots;
if (b43_debug(ring->dev, B43_DBG_DMAVERBOSE)) {
b43dbg(ring->dev->wl,
"max_used_slots increased to %d on %s ring %d\n",
ring->max_used_slots,
ring->tx ? "TX" : "RX", ring->index);
}
}
static inline int should_inject_overflow(struct b43_dmaring *ring)
{
#ifdef CONFIG_B43_DEBUG
if (unlikely(b43_debug(ring->dev, B43_DBG_DMAOVERFLOW))) {
unsigned long next_overflow;
next_overflow = ring->last_injected_overflow + HZ;
if (time_after(jiffies, next_overflow)) {
ring->last_injected_overflow = jiffies;
b43dbg(ring->dev->wl,
"Injecting TX ring overflow on "
"DMA controller %d\n", ring->index);
return 1;
}
}
#endif
return 0;
}
static inline int should_inject_overflow(struct b43_dmaring *ring)
{
#ifdef CPTCFG_B43_DEBUG
if (unlikely(b43_debug(ring->dev, B43_DBG_DMAOVERFLOW))) {
/* Check if we should inject another ringbuffer overflow
* to test handling of this situation in the stack. */
unsigned long next_overflow;
next_overflow = ring->last_injected_overflow + HZ;
if (time_after(jiffies, next_overflow)) {
ring->last_injected_overflow = jiffies;
b43dbg(ring->dev->wl,
"Injecting TX ring overflow on "
"DMA controller %d\n", ring->index);
return 1;
}
}
#endif /* CPTCFG_B43_DEBUG */
return 0;
}
void b43_dma_handle_txstatus(struct b43_wldev *dev,
const struct b43_txstatus *status)
{
const struct b43_dma_ops *ops;
struct b43_dmaring *ring;
struct b43_dmadesc_meta *meta;
static const struct b43_txstatus fake; /* filled with 0 */
const struct b43_txstatus *txstat;
int slot, firstused;
bool frame_succeed;
int skip;
static u8 err_out1, err_out2;
ring = parse_cookie(dev, status->cookie, &slot);
if (unlikely(!ring))
return;
B43_WARN_ON(!ring->tx);
/* Sanity check: TX packets are processed in-order on one ring.
* Check if the slot deduced from the cookie really is the first
* used slot. */
firstused = ring->current_slot - ring->used_slots + 1;
if (firstused < 0)
firstused = ring->nr_slots + firstused;
skip = 0;
if (unlikely(slot != firstused)) {
/* This possibly is a firmware bug and will result in
* malfunction, memory leaks and/or stall of DMA functionality.
*/
if (slot == next_slot(ring, next_slot(ring, firstused))) {
/* If a single header/data pair was missed, skip over
* the first two slots in an attempt to recover.
*/
slot = firstused;
skip = 2;
if (!err_out1) {
/* Report the error once. */
b43dbg(dev->wl,
"Skip on DMA ring %d slot %d.\n",
ring->index, slot);
err_out1 = 1;
}
} else {
/* More than a single header/data pair were missed.
* Report this error once.
*/
if (!err_out2)
b43dbg(dev->wl,
"Out of order TX status report on DMA ring %d. Expected %d, but got %d\n",
ring->index, firstused, slot);
err_out2 = 1;
return;
}
}
ops = ring->ops;
while (1) {
B43_WARN_ON(slot < 0 || slot >= ring->nr_slots);
/* get meta - ignore returned value */
ops->idx2desc(ring, slot, &meta);
if (b43_dma_ptr_is_poisoned(meta->skb)) {
b43dbg(dev->wl, "Poisoned TX slot %d (first=%d) "
"on ring %d\n",
slot, firstused, ring->index);
break;
}
if (meta->skb) {
struct b43_private_tx_info *priv_info =
b43_get_priv_tx_info(IEEE80211_SKB_CB(meta->skb));
unmap_descbuffer(ring, meta->dmaaddr,
meta->skb->len, 1);
kfree(priv_info->bouncebuffer);
priv_info->bouncebuffer = NULL;
} else {
unmap_descbuffer(ring, meta->dmaaddr,
b43_txhdr_size(dev), 1);
}
if (meta->is_last_fragment) {
struct ieee80211_tx_info *info;
if (unlikely(!meta->skb)) {
/* This is a scatter-gather fragment of a frame,
* so the skb pointer must not be NULL.
*/
b43dbg(dev->wl, "TX status unexpected NULL skb "
"at slot %d (first=%d) on ring %d\n",
slot, firstused, ring->index);
break;
}
info = IEEE80211_SKB_CB(meta->skb);
/*
* Call back to inform the ieee80211 subsystem about
* the status of the transmission. When skipping over
* a missed TX status report, use a status structure
* filled with zeros to indicate that the frame was not
* sent (frame_count 0) and not acknowledged
*/
if (unlikely(skip))
txstat = &fake;
else
txstat = status;
frame_succeed = b43_fill_txstatus_report(dev, info,
txstat);
#ifdef CPTCFG_B43_DEBUG
if (frame_succeed)
ring->nr_succeed_tx_packets++;
else
ring->nr_failed_tx_packets++;
ring->nr_total_packet_tries += status->frame_count;
#endif /* DEBUG */
ieee80211_tx_status(dev->wl->hw, meta->skb);
/* skb will be freed by ieee80211_tx_status().
* Poison our pointer. */
meta->skb = B43_DMA_PTR_POISON;
} else {
/* No need to call free_descriptor_buffer here, as
* this is only the txhdr, which is not allocated.
*/
if (unlikely(meta->skb)) {
b43dbg(dev->wl, "TX status unexpected non-NULL skb "
"at slot %d (first=%d) on ring %d\n",
slot, firstused, ring->index);
break;
}
}
/* Everything unmapped and free'd. So it's not used anymore. */
ring->used_slots--;
if (meta->is_last_fragment && !skip) {
/* This is the last scatter-gather
* fragment of the frame. We are done. */
break;
}
slot = next_slot(ring, slot);
if (skip > 0)
--skip;
}
if (ring->stopped) {
B43_WARN_ON(free_slots(ring) < TX_SLOTS_PER_FRAME);
ring->stopped = false;
}
if (dev->wl->tx_queue_stopped[ring->queue_prio]) {
dev->wl->tx_queue_stopped[ring->queue_prio] = 0;
} else {
/* If the driver queue is running wake the corresponding
* mac80211 queue. */
ieee80211_wake_queue(dev->wl->hw, ring->queue_prio);
if (b43_debug(dev, B43_DBG_DMAVERBOSE)) {
b43dbg(dev->wl, "Woke up TX ring %d\n", ring->index);
}
}
/* Add work to the queue. */
ieee80211_queue_work(dev->wl->hw, &dev->wl->tx_work);
}
int b43_dma_tx(struct b43_wldev *dev, struct sk_buff *skb)
{
struct b43_dmaring *ring;
struct ieee80211_hdr *hdr;
int err = 0;
struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
hdr = (struct ieee80211_hdr *)skb->data;
if (info->flags & IEEE80211_TX_CTL_SEND_AFTER_DTIM) {
/* The multicast ring will be sent after the DTIM */
ring = dev->dma.tx_ring_mcast;
/* Set the more-data bit. Ucode will clear it on
* the last frame for us. */
hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_MOREDATA);
} else {
/* Decide by priority where to put this frame. */
ring = select_ring_by_priority(
dev, skb_get_queue_mapping(skb));
}
B43_WARN_ON(!ring->tx);
if (unlikely(ring->stopped)) {
/* We get here only because of a bug in mac80211.
* Because of a race, one packet may be queued after
* the queue is stopped, thus we got called when we shouldn't.
* For now, just refuse the transmit. */
if (b43_debug(dev, B43_DBG_DMAVERBOSE))
b43err(dev->wl, "Packet after queue stopped\n");
err = -ENOSPC;
goto out;
}
if (unlikely(WARN_ON(free_slots(ring) < TX_SLOTS_PER_FRAME))) {
/* If we get here, we have a real error with the queue
* full, but queues not stopped. */
b43err(dev->wl, "DMA queue overflow\n");
err = -ENOSPC;
goto out;
}
/* Assign the queue number to the ring (if not already done before)
* so TX status handling can use it. The queue to ring mapping is
* static, so we don't need to store it per frame. */
ring->queue_prio = skb_get_queue_mapping(skb);
err = dma_tx_fragment(ring, skb);
if (unlikely(err == -ENOKEY)) {
/* Drop this packet, as we don't have the encryption key
* anymore and must not transmit it unencrypted. */
ieee80211_free_txskb(dev->wl->hw, skb);
err = 0;
goto out;
}
if (unlikely(err)) {
b43err(dev->wl, "DMA tx mapping failure\n");
goto out;
}
if ((free_slots(ring) < TX_SLOTS_PER_FRAME) ||
should_inject_overflow(ring)) {
/* This TX ring is full. */
unsigned int skb_mapping = skb_get_queue_mapping(skb);
ieee80211_stop_queue(dev->wl->hw, skb_mapping);
dev->wl->tx_queue_stopped[skb_mapping] = 1;
ring->stopped = true;
if (b43_debug(dev, B43_DBG_DMAVERBOSE)) {
b43dbg(dev->wl, "Stopped TX ring %d\n", ring->index);
}
}
out:
return err;
}
int b43_dma_tx(struct b43_wldev *dev, struct sk_buff *skb)
{
struct b43_dmaring *ring;
struct ieee80211_hdr *hdr;
int err = 0;
struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
hdr = (struct ieee80211_hdr *)skb->data;
if (info->flags & IEEE80211_TX_CTL_SEND_AFTER_DTIM) {
ring = dev->dma.tx_ring_mcast;
hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_MOREDATA);
} else {
ring = select_ring_by_priority(
dev, skb_get_queue_mapping(skb));
}
B43_WARN_ON(!ring->tx);
if (unlikely(ring->stopped)) {
if (b43_debug(dev, B43_DBG_DMAVERBOSE))
b43err(dev->wl, "Packet after queue stopped\n");
err = -ENOSPC;
goto out;
}
if (unlikely(WARN_ON(free_slots(ring) < TX_SLOTS_PER_FRAME))) {
b43err(dev->wl, "DMA queue overflow\n");
err = -ENOSPC;
goto out;
}
ring->queue_prio = skb_get_queue_mapping(skb);
err = dma_tx_fragment(ring, skb);
if (unlikely(err == -ENOKEY)) {
/* Drop this packet, as we don't have the encryption key
* anymore and must not transmit it unencrypted. */
ieee80211_free_txskb(dev->wl->hw, skb);
err = 0;
goto out;
}
if (unlikely(err)) {
b43err(dev->wl, "DMA tx mapping failure\n");
goto out;
}
if ((free_slots(ring) < TX_SLOTS_PER_FRAME) ||
should_inject_overflow(ring)) {
unsigned int skb_mapping = skb_get_queue_mapping(skb);
ieee80211_stop_queue(dev->wl->hw, skb_mapping);
dev->wl->tx_queue_stopped[skb_mapping] = 1;
ring->stopped = true;
if (b43_debug(dev, B43_DBG_DMAVERBOSE)) {
b43dbg(dev->wl, "Stopped TX ring %d\n", ring->index);
}
}
out:
return err;
}
void b43_dma_handle_txstatus(struct b43_wldev *dev,
const struct b43_txstatus *status)
{
const struct b43_dma_ops *ops;
struct b43_dmaring *ring;
struct b43_dmadesc_meta *meta;
int slot, firstused;
bool frame_succeed;
ring = parse_cookie(dev, status->cookie, &slot);
if (unlikely(!ring))
return;
B43_WARN_ON(!ring->tx);
/* Sanity check: TX packets are processed in-order on one ring.
* Check if the slot deduced from the cookie really is the first
* used slot. */
firstused = ring->current_slot - ring->used_slots + 1;
if (firstused < 0)
firstused = ring->nr_slots + firstused;
if (unlikely(slot != firstused)) {
/* This possibly is a firmware bug and will result in
* malfunction, memory leaks and/or stall of DMA functionality. */
b43dbg(dev->wl, "Out of order TX status report on DMA ring %d. "
"Expected %d, but got %d\n",
ring->index, firstused, slot);
return;
}
ops = ring->ops;
while (1) {
B43_WARN_ON(slot < 0 || slot >= ring->nr_slots);
/* get meta - ignore returned value */
ops->idx2desc(ring, slot, &meta);
if (b43_dma_ptr_is_poisoned(meta->skb)) {
b43dbg(dev->wl, "Poisoned TX slot %d (first=%d) "
"on ring %d\n",
slot, firstused, ring->index);
break;
}
if (meta->skb) {
struct b43_private_tx_info *priv_info =
b43_get_priv_tx_info(IEEE80211_SKB_CB(meta->skb));
unmap_descbuffer(ring, meta->dmaaddr, meta->skb->len, 1);
kfree(priv_info->bouncebuffer);
priv_info->bouncebuffer = NULL;
} else {
unmap_descbuffer(ring, meta->dmaaddr,
b43_txhdr_size(dev), 1);
}
if (meta->is_last_fragment) {
struct ieee80211_tx_info *info;
if (unlikely(!meta->skb)) {
/* This is a scatter-gather fragment of a frame, so
* the skb pointer must not be NULL. */
b43dbg(dev->wl, "TX status unexpected NULL skb "
"at slot %d (first=%d) on ring %d\n",
slot, firstused, ring->index);
break;
}
info = IEEE80211_SKB_CB(meta->skb);
/*
* Call back to inform the ieee80211 subsystem about
* the status of the transmission.
*/
frame_succeed = b43_fill_txstatus_report(dev, info, status);
#ifdef CONFIG_B43_DEBUG
if (frame_succeed)
ring->nr_succeed_tx_packets++;
else
ring->nr_failed_tx_packets++;
ring->nr_total_packet_tries += status->frame_count;
#endif /* DEBUG */
ieee80211_tx_status(dev->wl->hw, meta->skb);
/* skb will be freed by ieee80211_tx_status().
* Poison our pointer. */
meta->skb = B43_DMA_PTR_POISON;
} else {
/* No need to call free_descriptor_buffer here, as
* this is only the txhdr, which is not allocated.
*/
if (unlikely(meta->skb)) {
b43dbg(dev->wl, "TX status unexpected non-NULL skb "
"at slot %d (first=%d) on ring %d\n",
slot, firstused, ring->index);
break;
}
}
/* Everything unmapped and free'd. So it's not used anymore. */
ring->used_slots--;
if (meta->is_last_fragment) {
/* This is the last scatter-gather
* fragment of the frame. We are done. */
break;
}
slot = next_slot(ring, slot);
}
if (ring->stopped) {
B43_WARN_ON(free_slots(ring) < TX_SLOTS_PER_FRAME);
ieee80211_wake_queue(dev->wl->hw, ring->queue_prio);
ring->stopped = 0;
if (b43_debug(dev, B43_DBG_DMAVERBOSE)) {
b43dbg(dev->wl, "Woke up TX ring %d\n", ring->index);
}
}
}
