rt2x00: Replace statically allocated DMA buffers with mapped skb's.

The current PCI drivers require a lot of pre-allocated DMA buffers. Reduce this
by using dynamically mapped skb's (using pci_map_single) instead of the pre-
allocated DMA buffers that are allocated at device start-up time.

At the same time move common RX path code into rt2x00lib from rt2x00pci and
rt2x00usb, as the RX paths now are now almost the same.

Signed-off-by: Gertjan van Wingerde <gwingerde@kpnplanet.nl>
Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 9 insertions, 7 deletions

diff --git a/drivers/net/wireless/rt2x00/rt2x00queue.h b/drivers/net/wireless/rt2x00/rt2x00queue.h
index fcf52520b016..192b6e789a7f 100644
--- a/drivers/net/wireless/rt2x00/rt2x00queue.h
+++ b/drivers/net/wireless/rt2x00/rt2x00queue.h
@@ -83,9 +83,10 @@ enum data_queue_qid {
  * enum skb_frame_desc_flags: Flags for &struct skb_frame_desc
  *
  */
-//enum skb_frame_desc_flags {
-//      TEMPORARILY EMPTY
-//};
+enum skb_frame_desc_flags {
+        SKBDESC_DMA_MAPPED_RX = (1 << 0),
+        SKBDESC_DMA_MAPPED_TX = (1 << 1),
+};
 
 /**
  * struct skb_frame_desc: Descriptor information for the skb buffer
@@ -94,19 +95,20 @@ enum data_queue_qid {
  * this structure should not exceed the size of that array (40 bytes).
  *
  * @flags: Frame flags, see &enum skb_frame_desc_flags.
- * @data: Pointer to data part of frame (Start of ieee80211 header).
+ * @desc_len: Length of the frame descriptor.
  * @desc: Pointer to descriptor part of the frame.
  *      Note that this pointer could point to something outside
  *      of the scope of the skb->data pointer.
- * @data_len: Length of the frame data.
- * @desc_len: Length of the frame descriptor.
+ * @skb_dma: (PCI-only) the DMA address associated with the sk buffer.
  * @entry: The entry to which this sk buffer belongs.
  */
 struct skb_frame_desc {
         unsigned int flags;
 
-        void *desc;
         unsigned int desc_len;
+        void *desc;
+
+        dma_addr_t skb_dma;
 
         struct queue_entry *entry;
 };