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rt2x00: Centralize allocation of RX skbs.
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In preparation of replacing the statically allocated DMA buffers with
dynamically mapped skbs, centralize the allocation of RX skbs to rt2x00queue.c
and let rt2x00pci already use them.

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>
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Gertjan van Wingerde authored and John W. Linville committed Jun 26, 2008
1 parent 14a3bf8 commit 30caa6e
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Showing 4 changed files with 113 additions and 66 deletions.
10 changes: 8 additions & 2 deletions drivers/net/wireless/rt2x00/rt2x00.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -899,10 +899,16 @@ static inline u16 get_duration_res(const unsigned int size, const u8 rate)
}

/**
* rt2x00queue_alloc_rxskb - allocate a skb for RX purposes.
* rt2x00queue_alloc_skb - allocate a skb.
* @queue: The queue for which the skb will be applicable.
*/
struct sk_buff *rt2x00queue_alloc_rxskb(struct data_queue *queue);
struct sk_buff *rt2x00queue_alloc_skb(struct data_queue *queue);

/**
* rt2x00queue_free_skb - free a skb
* @skb: The skb to free.
*/
void rt2x00queue_free_skb(struct sk_buff *skb);

/**
* rt2x00queue_create_tx_descriptor - Create TX descriptor from mac80211 input
Expand Down
77 changes: 49 additions & 28 deletions drivers/net/wireless/rt2x00/rt2x00pci.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -74,13 +74,59 @@ EXPORT_SYMBOL_GPL(rt2x00pci_write_tx_data);
/*
* TX/RX data handlers.
*/
static void rt2x00pci_rxdone_entry(struct rt2x00_dev *rt2x00dev,
struct queue_entry *entry)
{
struct sk_buff *skb;
struct skb_frame_desc *skbdesc;
struct rxdone_entry_desc rxdesc;
struct queue_entry_priv_pci *entry_priv = entry->priv_data;

/*
* Allocate a new sk_buffer. If no new buffer available, drop the
* received frame and reuse the existing buffer.
*/
skb = rt2x00queue_alloc_skb(entry->queue);
if (!skb)
return;

/*
* Extract the RXD details.
*/
memset(&rxdesc, 0, sizeof(rxdesc));
rt2x00dev->ops->lib->fill_rxdone(entry, &rxdesc);

/*
* Copy the received data to the entries' skb.
*/
memcpy(entry->skb->data, entry_priv->data, rxdesc.size);
skb_trim(entry->skb, rxdesc.size);

/*
* Fill in skb descriptor
*/
skbdesc = get_skb_frame_desc(entry->skb);
memset(skbdesc, 0, sizeof(*skbdesc));
skbdesc->desc = entry_priv->desc;
skbdesc->desc_len = entry->queue->desc_size;
skbdesc->entry = entry;

/*
* Send the frame to rt2x00lib for further processing.
*/
rt2x00lib_rxdone(entry, &rxdesc);

/*
* Replace the entries' skb with the newly allocated one.
*/
entry->skb = skb;
}

void rt2x00pci_rxdone(struct rt2x00_dev *rt2x00dev)
{
struct data_queue *queue = rt2x00dev->rx;
struct queue_entry *entry;
struct queue_entry_priv_pci *entry_priv;
struct skb_frame_desc *skbdesc;
struct rxdone_entry_desc rxdesc;
u32 word;

while (1) {
Expand All @@ -91,32 +137,7 @@ void rt2x00pci_rxdone(struct rt2x00_dev *rt2x00dev)
if (rt2x00_get_field32(word, RXD_ENTRY_OWNER_NIC))
break;

memset(&rxdesc, 0, sizeof(rxdesc));
rt2x00dev->ops->lib->fill_rxdone(entry, &rxdesc);

/*
* Allocate the sk_buffer and copy all data into it.
*/
entry->skb = rt2x00queue_alloc_rxskb(queue);
if (!entry->skb)
return;

memcpy(entry->skb->data, entry_priv->data, rxdesc.size);
skb_trim(entry->skb, rxdesc.size);

/*
* Fill in skb descriptor
*/
skbdesc = get_skb_frame_desc(entry->skb);
memset(skbdesc, 0, sizeof(*skbdesc));
skbdesc->desc = entry_priv->desc;
skbdesc->desc_len = queue->desc_size;
skbdesc->entry = entry;

/*
* Send the frame to rt2x00lib for further processing.
*/
rt2x00lib_rxdone(entry, &rxdesc);
rt2x00pci_rxdone_entry(rt2x00dev, entry);

if (test_bit(DEVICE_ENABLED_RADIO, &queue->rt2x00dev->flags)) {
rt2x00_set_field32(&word, RXD_ENTRY_OWNER_NIC, 1);
Expand Down
71 changes: 54 additions & 17 deletions drivers/net/wireless/rt2x00/rt2x00queue.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -29,7 +29,7 @@
#include "rt2x00.h"
#include "rt2x00lib.h"

struct sk_buff *rt2x00queue_alloc_rxskb(struct data_queue *queue)
struct sk_buff *rt2x00queue_alloc_skb(struct data_queue *queue)
{
struct sk_buff *skb;
unsigned int frame_size;
Expand All @@ -42,17 +42,10 @@ struct sk_buff *rt2x00queue_alloc_rxskb(struct data_queue *queue)
frame_size = queue->data_size + queue->desc_size;

/*
* For the allocation we should keep a few things in mind:
* 1) 4byte alignment of 802.11 payload
*
* For (1) we need at most 4 bytes to guarentee the correct
* alignment. We are going to optimize the fact that the chance
* that the 802.11 header_size % 4 == 2 is much bigger then
* anything else. However since we need to move the frame up
* to 3 bytes to the front, which means we need to preallocate
* 6 bytes.
* Reserve a few bytes extra headroom to allow drivers some moving
* space (e.g. for alignment), while keeping the skb aligned.
*/
reserved_size = 6;
reserved_size = 8;

/*
* Allocate skbuffer.
Expand All @@ -66,7 +59,13 @@ struct sk_buff *rt2x00queue_alloc_rxskb(struct data_queue *queue)

return skb;
}
EXPORT_SYMBOL_GPL(rt2x00queue_alloc_rxskb);
EXPORT_SYMBOL_GPL(rt2x00queue_alloc_skb);

void rt2x00queue_free_skb(struct sk_buff *skb)
{
dev_kfree_skb_any(skb);
}
EXPORT_SYMBOL_GPL(rt2x00queue_free_skb);

void rt2x00queue_create_tx_descriptor(struct queue_entry *entry,
struct txentry_desc *txdesc)
Expand Down Expand Up @@ -422,12 +421,45 @@ static int rt2x00queue_alloc_entries(struct data_queue *queue,
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++) {
if (queue->entries[i].skb)
rt2x00queue_free_skb(queue->entries[i].skb);
}
}

static int rt2x00queue_alloc_skbs(struct data_queue *queue)
{
unsigned int i;
struct sk_buff *skb;

for (i = 0; i < queue->limit; i++) {
skb = rt2x00queue_alloc_skb(queue);
if (!skb)
goto exit;

queue->entries[i].skb = skb;
}

return 0;

exit:
rt2x00queue_free_skbs(queue);

return -ENOMEM;
}

int rt2x00queue_initialize(struct rt2x00_dev *rt2x00dev)
{
struct data_queue *queue;
int status;


status = rt2x00queue_alloc_entries(rt2x00dev->rx, rt2x00dev->ops->rx);
if (status)
goto exit;
Expand All @@ -442,11 +474,14 @@ int rt2x00queue_initialize(struct rt2x00_dev *rt2x00dev)
if (status)
goto exit;

if (!test_bit(DRIVER_REQUIRE_ATIM_QUEUE, &rt2x00dev->flags))
return 0;
if (test_bit(DRIVER_REQUIRE_ATIM_QUEUE, &rt2x00dev->flags)) {
status = rt2x00queue_alloc_entries(&rt2x00dev->bcn[1],
rt2x00dev->ops->atim);
if (status)
goto exit;
}

status = rt2x00queue_alloc_entries(&rt2x00dev->bcn[1],
rt2x00dev->ops->atim);
status = rt2x00queue_alloc_skbs(rt2x00dev->rx);
if (status)
goto exit;

Expand All @@ -464,6 +499,8 @@ 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;
Expand Down
21 changes: 2 additions & 19 deletions drivers/net/wireless/rt2x00/rt2x00usb.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -300,7 +300,7 @@ static void rt2x00usb_interrupt_rxdone(struct urb *urb)
* If allocation fails, we should drop the current frame
* so we can recycle the existing sk buffer for the new frame.
*/
skb = rt2x00queue_alloc_rxskb(entry->queue);
skb = rt2x00queue_alloc_skb(entry->queue);
if (!skb)
goto skip_entry;

Expand Down Expand Up @@ -434,8 +434,6 @@ static void rt2x00usb_free_urb(struct rt2x00_dev *rt2x00dev,
entry_priv = queue->entries[i].priv_data;
usb_kill_urb(entry_priv->urb);
usb_free_urb(entry_priv->urb);
if (queue->entries[i].skb)
kfree_skb(queue->entries[i].skb);
}

/*
Expand All @@ -457,10 +455,7 @@ static void rt2x00usb_free_urb(struct rt2x00_dev *rt2x00dev,
int rt2x00usb_initialize(struct rt2x00_dev *rt2x00dev)
{
struct data_queue *queue;
struct sk_buff *skb;
unsigned int entry_size;
unsigned int i;
int uninitialized_var(status);
int status;

/*
* Allocate DMA
Expand All @@ -471,18 +466,6 @@ int rt2x00usb_initialize(struct rt2x00_dev *rt2x00dev)
goto exit;
}

/*
* For the RX queue, skb's should be allocated.
*/
entry_size = rt2x00dev->rx->data_size + rt2x00dev->rx->desc_size;
for (i = 0; i < rt2x00dev->rx->limit; i++) {
skb = rt2x00queue_alloc_rxskb(rt2x00dev->rx);
if (!skb)
goto exit;

rt2x00dev->rx->entries[i].skb = skb;
}

return 0;

exit:
Expand Down

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