2011-07-11 00:52:49

by Michał Mirosław

Subject: [PATCH v2 04/46] net/wireless: p54: remove useless dma_sync_single_for_device(DMA_FROM_DEVICE)

Also constify pointers used in frame parsers to verify assumptions.

Signed-off-by: Michał Mirosław <[email protected]>
---
drivers/net/wireless/p54/p54pci.c | 2 --
drivers/net/wireless/p54/txrx.c | 22 +++++++++++-----------
2 files changed, 11 insertions(+), 13 deletions(-)

diff --git a/drivers/net/wireless/p54/p54pci.c b/drivers/net/wireless/p54/p54pci.c
index 1b75317..4491d33 100644
--- a/drivers/net/wireless/p54/p54pci.c
+++ b/drivers/net/wireless/p54/p54pci.c
@@ -229,8 +229,6 @@ static void p54p_check_rx_ring(struct ieee80211_hw *dev, u32 *index,
desc->host_addr = cpu_to_le32(0);
} else {
skb_trim(skb, 0);
- pci_dma_sync_single_for_device(priv->pdev, dma_addr,
- priv->common.rx_mtu + 32, PCI_DMA_FROMDEVICE);
desc->len = cpu_to_le16(priv->common.rx_mtu + 32);
}

diff --git a/drivers/net/wireless/p54/txrx.c b/drivers/net/wireless/p54/txrx.c
index 042842e..b7ecd89 100644
--- a/drivers/net/wireless/p54/txrx.c
+++ b/drivers/net/wireless/p54/txrx.c
@@ -325,7 +325,7 @@ static void p54_pspoll_workaround(struct p54_common *priv, struct sk_buff *skb)

static int p54_rx_data(struct p54_common *priv, struct sk_buff *skb)
{
- struct p54_rx_data *hdr = (struct p54_rx_data *) skb->data;
+ const struct p54_rx_data *hdr = (void *)skb->data;
struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb);
u16 freq = le16_to_cpu(hdr->freq);
size_t header_len = sizeof(*hdr);
@@ -387,8 +387,8 @@ static int p54_rx_data(struct p54_common *priv, struct sk_buff *skb)

static void p54_rx_frame_sent(struct p54_common *priv, struct sk_buff *skb)
{
- struct p54_hdr *hdr = (struct p54_hdr *) skb->data;
- struct p54_frame_sent *payload = (struct p54_frame_sent *) hdr->data;
+ const struct p54_hdr *hdr = (void *)skb->data;
+ const struct p54_frame_sent *payload = (void *)hdr->data;
struct ieee80211_tx_info *info;
struct p54_hdr *entry_hdr;
struct p54_tx_data *entry_data;
@@ -481,8 +481,8 @@ static void p54_rx_frame_sent(struct p54_common *priv, struct sk_buff *skb)
static void p54_rx_eeprom_readback(struct p54_common *priv,
struct sk_buff *skb)
{
- struct p54_hdr *hdr = (struct p54_hdr *) skb->data;
- struct p54_eeprom_lm86 *eeprom = (struct p54_eeprom_lm86 *) hdr->data;
+ const struct p54_hdr *hdr = (void *)skb->data;
+ const struct p54_eeprom_lm86 *eeprom = (void *)hdr->data;
struct sk_buff *tmp;

if (!priv->eeprom)
@@ -504,8 +504,8 @@ static void p54_rx_eeprom_readback(struct p54_common *priv,

static void p54_rx_stats(struct p54_common *priv, struct sk_buff *skb)
{
- struct p54_hdr *hdr = (struct p54_hdr *) skb->data;
- struct p54_statistics *stats = (struct p54_statistics *) hdr->data;
+ const struct p54_hdr *hdr = (void *)skb->data;
+ const struct p54_statistics *stats = (void *)hdr->data;
struct sk_buff *tmp;
u32 tsf32;

@@ -529,8 +529,8 @@ static void p54_rx_stats(struct p54_common *priv, struct sk_buff *skb)

static void p54_rx_trap(struct p54_common *priv, struct sk_buff *skb)
{
- struct p54_hdr *hdr = (struct p54_hdr *) skb->data;
- struct p54_trap *trap = (struct p54_trap *) hdr->data;
+ const struct p54_hdr *hdr = (void *)skb->data;
+ const struct p54_trap *trap = (void *)hdr->data;
u16 event = le16_to_cpu(trap->event);
u16 freq = le16_to_cpu(trap->frequency);

@@ -565,7 +565,7 @@ static void p54_rx_trap(struct p54_common *priv, struct sk_buff *skb)

static int p54_rx_control(struct p54_common *priv, struct sk_buff *skb)
{
- struct p54_hdr *hdr = (struct p54_hdr *) skb->data;
+ const struct p54_hdr *hdr = (void *)skb->data;

switch (le16_to_cpu(hdr->type)) {
case P54_CONTROL_TYPE_TXDONE:
@@ -595,7 +595,7 @@ static int p54_rx_control(struct p54_common *priv, struct sk_buff *skb)
int p54_rx(struct ieee80211_hw *dev, struct sk_buff *skb)
{
struct p54_common *priv = dev->priv;
- u16 type = le16_to_cpu(*((__le16 *)skb->data));
+ u16 type = le16_to_cpu(*(const __le16 *)skb->data);

if (type & P54_HDR_FLAG_CONTROL)
return p54_rx_control(priv, skb);
--
1.7.5.4

2011-07-11 15:15:21

by Pavel Roskin

Subject: Re: [PATCH v2 04/46] net/wireless: p54: remove useless dma_sync_single_for_device(DMA_FROM_DEVICE)

On 07/10/2011 08:52 PM, Michał Mirosław wrote:
> Also constify pointers used in frame parsers to verify assumptions.

Cleanups are better done separately.

> - u16 type = le16_to_cpu(*((__le16 *)skb->data));
> + u16 type = le16_to_cpu(*(const __le16 *)skb->data);

I think it would be more appropriate to use get_unaligned_le16() here.
No casts should be needed then.

That's not an objection, just a suggestion :)

--
Regards,
Pavel Roskin

2011-07-12 04:50:33

by Felix Fietkau

Subject: Re: [PATCH v2 04/46] net/wireless: p54: remove useless dma_sync_single_for_device(DMA_FROM_DEVICE)

On 2011-07-11 8:52 AM, Michał Mirosław wrote:
> Also constify pointers used in frame parsers to verify assumptions.
>
> Signed-off-by: Michał Mirosław<[email protected]>
> ---
> drivers/net/wireless/p54/p54pci.c | 2 --
> drivers/net/wireless/p54/txrx.c | 22 +++++++++++-----------
> 2 files changed, 11 insertions(+), 13 deletions(-)
>
> diff --git a/drivers/net/wireless/p54/p54pci.c b/drivers/net/wireless/p54/p54pci.c
> index 1b75317..4491d33 100644
> --- a/drivers/net/wireless/p54/p54pci.c
> +++ b/drivers/net/wireless/p54/p54pci.c
> @@ -229,8 +229,6 @@ static void p54p_check_rx_ring(struct ieee80211_hw *dev, u32 *index,
> desc->host_addr = cpu_to_le32(0);
> } else {
> skb_trim(skb, 0);
> - pci_dma_sync_single_for_device(priv->pdev, dma_addr,
> - priv->common.rx_mtu + 32, PCI_DMA_FROMDEVICE);
> desc->len = cpu_to_le16(priv->common.rx_mtu + 32);
> }
>
This part does not look correct to me - same issue as your ath9k change,
which I commented on earlier. I don't think this call to
dma_sync_single_for_device is useless

- Felix