#define GET_DURATION(__size, __rate) (((__size) * 8 * 10) / (__rate))
#define GET_DURATION_RES(__size, __rate)(((__size) * 8 * 10) % (__rate))
+/*
+ * Determine the alignment requirement,
+ * to make sure the 802.11 payload is padded to a 4-byte boundrary
+ * we must determine the address of the payload and calculate the
+ * amount of bytes needed to move the data.
+ */
+#define ALIGN_SIZE(__skb, __header) \
+ ( ((unsigned long)((__skb)->data + (__header))) & 3 )
+
/*
* Standard timing and size defines.
* These values should follow the ieee80211 specifications.
DRIVER_REQUIRE_SCHEDULED,
DRIVER_REQUIRE_DMA,
DRIVER_REQUIRE_COPY_IV,
+ DRIVER_REQUIRE_L2PAD,
/*
* Driver features
__set_bit(ENTRY_TXD_ENCRYPT_PAIRWISE, &txdesc->flags);
txdesc->key_idx = hw_key->hw_key_idx;
- txdesc->iv_offset = ieee80211_get_hdrlen_from_skb(entry->skb);
+ txdesc->iv_offset = txdesc->header_length;
txdesc->iv_len = hw_key->iv_len;
if (!(hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV))
skb_pull(skb, txdesc->iv_len);
/* IV/EIV data has officially be stripped */
- skbdesc->flags |= FRAME_DESC_IV_STRIPPED;
+ skbdesc->flags |= SKBDESC_IV_STRIPPED;
}
-void rt2x00crypto_tx_insert_iv(struct sk_buff *skb)
+void rt2x00crypto_tx_insert_iv(struct sk_buff *skb, unsigned int header_length)
{
struct skb_frame_desc *skbdesc = get_skb_frame_desc(skb);
- unsigned int header_length = ieee80211_get_hdrlen_from_skb(skb);
const unsigned int iv_len =
((!!(skbdesc->iv[0])) * 4) + ((!!(skbdesc->iv[1])) * 4);
- if (!(skbdesc->flags & FRAME_DESC_IV_STRIPPED))
+ if (!(skbdesc->flags & SKBDESC_IV_STRIPPED))
return;
skb_push(skb, iv_len);
memcpy(skb->data + header_length, skbdesc->iv, iv_len);
/* IV/EIV data has returned into the frame */
- skbdesc->flags &= ~FRAME_DESC_IV_STRIPPED;
+ skbdesc->flags &= ~SKBDESC_IV_STRIPPED;
}
-void rt2x00crypto_rx_insert_iv(struct sk_buff *skb, unsigned int align,
+void rt2x00crypto_rx_insert_iv(struct sk_buff *skb, bool l2pad,
unsigned int header_length,
struct rxdone_entry_desc *rxdesc)
{
unsigned int payload_len = rxdesc->size - header_length;
+ unsigned int align = ALIGN_SIZE(skb, header_length);
unsigned int iv_len;
unsigned int icv_len;
unsigned int transfer = 0;
}
/*
- * Make room for new data, note that we increase both
- * headsize and tailsize when required. The tailsize is
- * only needed when ICV data needs to be inserted and
- * the padding is smaller than the ICV data.
- * When alignment requirements is greater than the
- * ICV data we must trim the skb to the correct size
- * because we need to remove the extra bytes.
+ * Make room for new data. There are 2 possibilities
+ * either the alignment is already present between
+ * the 802.11 header and payload. In that case we
+ * we have to move the header less then the iv_len
+ * since we can use the already available l2pad bytes
+ * for the iv data.
+ * When the alignment must be added manually we must
+ * move the header more then iv_len since we must
+ * make room for the payload move as well.
*/
- skb_push(skb, iv_len + align);
- if (align < icv_len)
- skb_put(skb, icv_len - align);
- else if (align > icv_len)
- skb_trim(skb, rxdesc->size + iv_len + icv_len);
+ if (l2pad) {
+ skb_push(skb, iv_len - align);
+ skb_put(skb, icv_len);
- /* Move ieee80211 header */
- memmove(skb->data + transfer,
- skb->data + transfer + iv_len + align,
- header_length);
- transfer += header_length;
+ /* Move ieee80211 header */
+ memmove(skb->data + transfer,
+ skb->data + transfer + (iv_len - align),
+ header_length);
+ transfer += header_length;
+ } else {
+ skb_push(skb, iv_len + align);
+ if (align < icv_len)
+ skb_put(skb, icv_len - align);
+ else if (align > icv_len)
+ skb_trim(skb, rxdesc->size + iv_len + icv_len);
+
+ /* Move ieee80211 header */
+ memmove(skb->data + transfer,
+ skb->data + transfer + iv_len + align,
+ header_length);
+ transfer += header_length;
+ }
/* Copy IV/EIV data */
memcpy(skb->data + transfer, rxdesc->iv, iv_len);
transfer += iv_len;
- /* Move payload */
- if (align) {
+ /*
+ * Move payload for alignment purposes. Note that
+ * this is only needed when no l2 padding is present.
+ */
+ if (!l2pad) {
memmove(skb->data + transfer,
skb->data + transfer + align,
payload_len);
struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(entry->skb);
struct skb_frame_desc *skbdesc = get_skb_frame_desc(entry->skb);
enum data_queue_qid qid = skb_get_queue_mapping(entry->skb);
+ unsigned int header_length = ieee80211_get_hdrlen_from_skb(entry->skb);
u8 rate_idx, rate_flags;
/*
*/
rt2x00queue_unmap_skb(rt2x00dev, entry->skb);
+ /*
+ * Remove L2 padding which was added during
+ */
+ if (test_bit(DRIVER_REQUIRE_L2PAD, &rt2x00dev->flags))
+ rt2x00queue_payload_align(entry->skb, true, header_length);
+
/*
* If the IV/EIV data was stripped from the frame before it was
* passed to the hardware, we should now reinsert it again because
* frame as it was passed to us.
*/
if (test_bit(CONFIG_SUPPORT_HW_CRYPTO, &rt2x00dev->flags))
- rt2x00crypto_tx_insert_iv(entry->skb);
+ rt2x00crypto_tx_insert_iv(entry->skb, header_length);
/*
* Send frame to debugfs immediately, after this call is completed
struct ieee80211_supported_band *sband;
const struct rt2x00_rate *rate;
unsigned int header_length;
- unsigned int align;
+ bool l2pad;
unsigned int i;
int idx = -1;
memset(&rxdesc, 0, sizeof(rxdesc));
rt2x00dev->ops->lib->fill_rxdone(entry, &rxdesc);
+ /* Trim buffer to correct size */
+ skb_trim(entry->skb, rxdesc.size);
+
/*
* The data behind the ieee80211 header must be
* aligned on a 4 byte boundary.
*/
header_length = ieee80211_get_hdrlen_from_skb(entry->skb);
- align = ((unsigned long)(entry->skb->data + header_length)) & 3;
+ l2pad = !!(rxdesc.dev_flags & RXDONE_L2PAD);
/*
* Hardware might have stripped the IV/EIV/ICV data,
* in which case we should reinsert the data into the frame.
*/
if ((rxdesc.dev_flags & RXDONE_CRYPTO_IV) &&
- (rxdesc.flags & RX_FLAG_IV_STRIPPED)) {
- rt2x00crypto_rx_insert_iv(entry->skb, align,
- header_length, &rxdesc);
- } else if (align) {
- skb_push(entry->skb, align);
- /* Move entire frame in 1 command */
- memmove(entry->skb->data, entry->skb->data + align,
- rxdesc.size);
- }
-
- /* Update data pointers, trim buffer to correct size */
- skb_trim(entry->skb, rxdesc.size);
+ (rxdesc.flags & RX_FLAG_IV_STRIPPED))
+ rt2x00crypto_rx_insert_iv(entry->skb, l2pad, header_length,
+ &rxdesc);
+ else
+ rt2x00queue_payload_align(entry->skb, l2pad, header_length);
/*
* Update RX statistics.
*/
void rt2x00queue_free_skb(struct rt2x00_dev *rt2x00dev, struct sk_buff *skb);
+/**
+ * rt2x00queue_payload_align - Align 802.11 payload to 4-byte boundary
+ * @skb: The skb to align
+ * @l2pad: Should L2 padding be used
+ * @header_length: Length of 802.11 header
+ *
+ * This function prepares the @skb to be send to the device or mac80211.
+ * If @l2pad is set to true padding will occur between the 802.11 header
+ * and payload. Otherwise the padding will be done in front of the 802.11
+ * header.
+ * When @l2pad is set the function will check for the &SKBDESC_L2_PADDED
+ * flag in &skb_frame_desc. If that flag is set, the padding is removed
+ * and the flag cleared. Otherwise the padding is added and the flag is set.
+ */
+void rt2x00queue_payload_align(struct sk_buff *skb,
+ bool l2pad, unsigned int header_length);
+
/**
* rt2x00queue_write_tx_frame - Write TX frame to hardware
* @queue: Queue over which the frame should be send
struct txentry_desc *txdesc);
void rt2x00crypto_tx_remove_iv(struct sk_buff *skb,
struct txentry_desc *txdesc);
-void rt2x00crypto_tx_insert_iv(struct sk_buff *skb);
-void rt2x00crypto_rx_insert_iv(struct sk_buff *skb, unsigned int align,
+void rt2x00crypto_tx_insert_iv(struct sk_buff *skb, unsigned int header_length);
+void rt2x00crypto_rx_insert_iv(struct sk_buff *skb, bool l2pad,
unsigned int header_length,
struct rxdone_entry_desc *rxdesc);
#else
{
}
-static inline void rt2x00crypto_tx_insert_iv(struct sk_buff *skb)
+static inline void rt2x00crypto_tx_insert_iv(struct sk_buff *skb,
+ unsigned int header_length)
{
}
-static inline void rt2x00crypto_rx_insert_iv(struct sk_buff *skb,
- unsigned int align,
+static inline void rt2x00crypto_rx_insert_iv(struct sk_buff *skb, bool l2pad,
unsigned int header_length,
struct rxdone_entry_desc *rxdesc)
{
dev_kfree_skb_any(skb);
}
+void rt2x00queue_payload_align(struct sk_buff *skb,
+ bool l2pad, unsigned int header_length)
+{
+ struct skb_frame_desc *skbdesc = get_skb_frame_desc(skb);
+ unsigned int frame_length = skb->len;
+ unsigned int align = ALIGN_SIZE(skb, header_length);
+
+ if (!align)
+ return;
+
+ if (l2pad) {
+ if (skbdesc->flags & SKBDESC_L2_PADDED) {
+ /* Remove L2 padding */
+ memmove(skb->data + align, skb->data, header_length);
+ skb_pull(skb, align);
+ skbdesc->flags &= ~SKBDESC_L2_PADDED;
+ } else {
+ /* Add L2 padding */
+ skb_push(skb, align);
+ memmove(skb->data, skb->data + align, header_length);
+ skbdesc->flags |= SKBDESC_L2_PADDED;
+ }
+ } else {
+ /* Generic payload alignment to 4-byte boundary */
+ skb_push(skb, align);
+ memmove(skb->data, skb->data + align, frame_length);
+ }
+}
+
static void rt2x00queue_create_tx_descriptor_seq(struct queue_entry *entry,
struct txentry_desc *txdesc)
{
txdesc->cw_max = entry->queue->cw_max;
txdesc->aifs = entry->queue->aifs;
+ /*
+ * Header and alignment information.
+ */
+ txdesc->header_length = ieee80211_get_hdrlen_from_skb(entry->skb);
+ txdesc->l2pad = ALIGN_SIZE(entry->skb, txdesc->header_length);
+
/*
* Check whether this frame is to be acked.
*/
rt2x00crypto_tx_remove_iv(skb, &txdesc);
}
+ if (test_bit(DRIVER_REQUIRE_L2PAD, &queue->rt2x00dev->flags))
+ rt2x00queue_payload_align(entry->skb, true,
+ txdesc.header_length);
+
/*
* It could be possible that the queue was corrupted and this
* call failed. Since we always return NETDEV_TX_OK to mac80211,
*
* @SKBDESC_DMA_MAPPED_RX: &skb_dma field has been mapped for RX
* @SKBDESC_DMA_MAPPED_TX: &skb_dma field has been mapped for TX
- * @FRAME_DESC_IV_STRIPPED: Frame contained a IV/EIV provided by
+ * @SKBDESC_IV_STRIPPED: Frame contained a IV/EIV provided by
* mac80211 but was stripped for processing by the driver.
+ * @SKBDESC_L2_PADDED: Payload has been padded for 4-byte alignment,
+ * the padded bytes are located between header and payload.
*/
enum skb_frame_desc_flags {
SKBDESC_DMA_MAPPED_RX = 1 << 0,
SKBDESC_DMA_MAPPED_TX = 1 << 1,
- FRAME_DESC_IV_STRIPPED = 1 << 2,
+ SKBDESC_IV_STRIPPED = 1 << 2,
+ SKBDESC_L2_PADDED = 1 << 3
};
/**
* @RXDONE_MY_BSS: Does this frame originate from device's BSS.
* @RXDONE_CRYPTO_IV: Driver provided IV/EIV data.
* @RXDONE_CRYPTO_ICV: Driver provided ICV data.
+ * @RXDONE_L2PAD: 802.11 payload has been padded to 4-byte boundary.
*/
enum rxdone_entry_desc_flags {
RXDONE_SIGNAL_PLCP = 1 << 0,
RXDONE_MY_BSS = 1 << 2,
RXDONE_CRYPTO_IV = 1 << 3,
RXDONE_CRYPTO_ICV = 1 << 4,
+ RXDONE_L2PAD = 1 << 5,
};
/**
*
* @flags: Descriptor flags (See &enum queue_entry_flags).
* @queue: Queue identification (See &enum data_queue_qid).
+ * @header_length: Length of 802.11 header.
+ * @l2pad: Amount of padding to align 802.11 payload to 4-byte boundrary.
* @length_high: PLCP length high word.
* @length_low: PLCP length low word.
* @signal: PLCP signal.
enum data_queue_qid queue;
+ u16 header_length;
+ u16 l2pad;
+
u16 length_high;
u16 length_low;
u16 signal;