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[PATCH] myri10ge: drop contiguous skb routines
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Drop the old routines that used the physically contigous skb now
that we use the physical pages. And rename myri10ge_page_rx_done()
to myri10ge_rx_done() as it was previously.

Signed-off-by: Brice Goglin <brice@myri.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
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Brice Goglin authored and Jeff Garzik committed Dec 11, 2006
1 parent c7dab99 commit 52ea6fb
Showing 1 changed file with 8 additions and 204 deletions.
212 changes: 8 additions & 204 deletions drivers/net/myri10ge/myri10ge.c
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Original file line number Diff line number Diff line change
Expand Up @@ -97,7 +97,6 @@ MODULE_LICENSE("Dual BSD/GPL");
#define MYRI10GE_MAX_FRAGS_PER_FRAME (MYRI10GE_MAX_ETHER_MTU/MYRI10GE_ALLOC_SIZE + 1)

struct myri10ge_rx_buffer_state {
struct sk_buff *skb;
struct page *page;
int page_offset;
DECLARE_PCI_UNMAP_ADDR(bus)
Expand Down Expand Up @@ -250,11 +249,6 @@ module_param(myri10ge_force_firmware, int, S_IRUGO);
MODULE_PARM_DESC(myri10ge_force_firmware,
"Force firmware to assume aligned completions\n");

static int myri10ge_skb_cross_4k = 0;
module_param(myri10ge_skb_cross_4k, int, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(myri10ge_skb_cross_4k,
"Can a small skb cross a 4KB boundary?\n");

static int myri10ge_initial_mtu = MYRI10GE_MAX_ETHER_MTU - ETH_HLEN;
module_param(myri10ge_initial_mtu, int, S_IRUGO);
MODULE_PARM_DESC(myri10ge_initial_mtu, "Initial MTU\n");
Expand Down Expand Up @@ -820,148 +814,6 @@ myri10ge_submit_8rx(struct mcp_kreq_ether_recv __iomem * dst,
mb();
}

/*
* Set of routines to get a new receive buffer. Any buffer which
* crosses a 4KB boundary must start on a 4KB boundary due to PCIe
* wdma restrictions. We also try to align any smaller allocation to
* at least a 16 byte boundary for efficiency. We assume the linux
* memory allocator works by powers of 2, and will not return memory
* smaller than 2KB which crosses a 4KB boundary. If it does, we fall
* back to allocating 2x as much space as required.
*
* We intend to replace large (>4KB) skb allocations by using
* pages directly and building a fraglist in the near future.
*/

static inline struct sk_buff *myri10ge_alloc_big(struct net_device *dev,
int bytes)
{
struct sk_buff *skb;
unsigned long data, roundup;

skb = netdev_alloc_skb(dev, bytes + 4096 + MXGEFW_PAD);
if (skb == NULL)
return NULL;

/* Correct skb->truesize so that socket buffer
* accounting is not confused the rounding we must
* do to satisfy alignment constraints.
*/
skb->truesize -= 4096;

data = (unsigned long)(skb->data);
roundup = (-data) & (4095);
skb_reserve(skb, roundup);
return skb;
}

/* Allocate 2x as much space as required and use whichever portion
* does not cross a 4KB boundary */
static inline struct sk_buff *myri10ge_alloc_small_safe(struct net_device *dev,
unsigned int bytes)
{
struct sk_buff *skb;
unsigned long data, boundary;

skb = netdev_alloc_skb(dev, 2 * (bytes + MXGEFW_PAD) - 1);
if (unlikely(skb == NULL))
return NULL;

/* Correct skb->truesize so that socket buffer
* accounting is not confused the rounding we must
* do to satisfy alignment constraints.
*/
skb->truesize -= bytes + MXGEFW_PAD;

data = (unsigned long)(skb->data);
boundary = (data + 4095UL) & ~4095UL;
if ((boundary - data) >= (bytes + MXGEFW_PAD))
return skb;

skb_reserve(skb, boundary - data);
return skb;
}

/* Allocate just enough space, and verify that the allocated
* space does not cross a 4KB boundary */
static inline struct sk_buff *myri10ge_alloc_small(struct net_device *dev,
int bytes)
{
struct sk_buff *skb;
unsigned long roundup, data, end;

skb = netdev_alloc_skb(dev, bytes + 16 + MXGEFW_PAD);
if (unlikely(skb == NULL))
return NULL;

/* Round allocated buffer to 16 byte boundary */
data = (unsigned long)(skb->data);
roundup = (-data) & 15UL;
skb_reserve(skb, roundup);
/* Verify that the data buffer does not cross a page boundary */
data = (unsigned long)(skb->data);
end = data + bytes + MXGEFW_PAD - 1;
if (unlikely(((end >> 12) != (data >> 12)) && (data & 4095UL))) {
printk(KERN_NOTICE
"myri10ge_alloc_small: small skb crossed 4KB boundary\n");
myri10ge_skb_cross_4k = 1;
dev_kfree_skb_any(skb);
skb = myri10ge_alloc_small_safe(dev, bytes);
}
return skb;
}

static inline int
myri10ge_getbuf(struct myri10ge_rx_buf *rx, struct myri10ge_priv *mgp,
int bytes, int idx)
{
struct net_device *dev = mgp->dev;
struct pci_dev *pdev = mgp->pdev;
struct sk_buff *skb;
dma_addr_t bus;
int len, retval = 0;

bytes += VLAN_HLEN; /* account for 802.1q vlan tag */

if ((bytes + MXGEFW_PAD) > (4096 - 16) /* linux overhead */ )
skb = myri10ge_alloc_big(dev, bytes);
else if (myri10ge_skb_cross_4k)
skb = myri10ge_alloc_small_safe(dev, bytes);
else
skb = myri10ge_alloc_small(dev, bytes);

if (unlikely(skb == NULL)) {
rx->alloc_fail++;
retval = -ENOBUFS;
goto done;
}

/* set len so that it only covers the area we
* need mapped for DMA */
len = bytes + MXGEFW_PAD;

bus = pci_map_single(pdev, skb->data, len, PCI_DMA_FROMDEVICE);
rx->info[idx].skb = skb;
pci_unmap_addr_set(&rx->info[idx], bus, bus);
pci_unmap_len_set(&rx->info[idx], len, len);
rx->shadow[idx].addr_low = htonl(MYRI10GE_LOWPART_TO_U32(bus));
rx->shadow[idx].addr_high = htonl(MYRI10GE_HIGHPART_TO_U32(bus));

done:
/* copy 8 descriptors (64-bytes) to the mcp at a time */
if ((idx & 7) == 7) {
if (rx->wc_fifo == NULL)
myri10ge_submit_8rx(&rx->lanai[idx - 7],
&rx->shadow[idx - 7]);
else {
mb();
myri10ge_pio_copy(rx->wc_fifo,
&rx->shadow[idx - 7], 64);
}
}
return retval;
}

static inline void myri10ge_vlan_ip_csum(struct sk_buff *skb, __wsum hw_csum)
{
struct vlan_hdr *vh = (struct vlan_hdr *)(skb->data);
Expand Down Expand Up @@ -1084,8 +936,8 @@ myri10ge_unmap_rx_page(struct pci_dev *pdev,
* page into an skb */

static inline int
myri10ge_page_rx_done(struct myri10ge_priv *mgp, struct myri10ge_rx_buf *rx,
int bytes, int len, __wsum csum)
myri10ge_rx_done(struct myri10ge_priv *mgp, struct myri10ge_rx_buf *rx,
int bytes, int len, __wsum csum)
{
struct sk_buff *skb;
struct skb_frag_struct rx_frags[MYRI10GE_MAX_FRAGS_PER_FRAME];
Expand Down Expand Up @@ -1148,54 +1000,6 @@ myri10ge_page_rx_done(struct myri10ge_priv *mgp, struct myri10ge_rx_buf *rx,
return 1;
}

static inline unsigned long
myri10ge_rx_done(struct myri10ge_priv *mgp, struct myri10ge_rx_buf *rx,
int bytes, int len, __wsum csum)
{
dma_addr_t bus;
struct sk_buff *skb;
int idx, unmap_len;

idx = rx->cnt & rx->mask;
rx->cnt++;

/* save a pointer to the received skb */
skb = rx->info[idx].skb;
bus = pci_unmap_addr(&rx->info[idx], bus);
unmap_len = pci_unmap_len(&rx->info[idx], len);

/* try to replace the received skb */
if (myri10ge_getbuf(rx, mgp, bytes, idx)) {
/* drop the frame -- the old skbuf is re-cycled */
mgp->stats.rx_dropped += 1;
return 0;
}

/* unmap the recvd skb */
pci_unmap_single(mgp->pdev, bus, unmap_len, PCI_DMA_FROMDEVICE);

/* mcp implicitly skips 1st bytes so that packet is properly
* aligned */
skb_reserve(skb, MXGEFW_PAD);

/* set the length of the frame */
skb_put(skb, len);

skb->protocol = eth_type_trans(skb, mgp->dev);
if (mgp->csum_flag) {
if ((skb->protocol == htons(ETH_P_IP)) ||
(skb->protocol == htons(ETH_P_IPV6))) {
skb->csum = csum;
skb->ip_summed = CHECKSUM_COMPLETE;
} else
myri10ge_vlan_ip_csum(skb, csum);
}

netif_receive_skb(skb);
mgp->dev->last_rx = jiffies;
return 1;
}

static inline void myri10ge_tx_done(struct myri10ge_priv *mgp, int mcp_index)
{
struct pci_dev *pdev = mgp->pdev;
Expand Down Expand Up @@ -1264,13 +1068,13 @@ static inline void myri10ge_clean_rx_done(struct myri10ge_priv *mgp, int *limit)
rx_done->entry[idx].length = 0;
checksum = csum_unfold(rx_done->entry[idx].checksum);
if (length <= mgp->small_bytes)
rx_ok = myri10ge_page_rx_done(mgp, &mgp->rx_small,
mgp->small_bytes,
length, checksum);
rx_ok = myri10ge_rx_done(mgp, &mgp->rx_small,
mgp->small_bytes,
length, checksum);
else
rx_ok = myri10ge_page_rx_done(mgp, &mgp->rx_big,
mgp->big_bytes,
length, checksum);
rx_ok = myri10ge_rx_done(mgp, &mgp->rx_big,
mgp->big_bytes,
length, checksum);
rx_packets += rx_ok;
rx_bytes += rx_ok * (unsigned long)length;
cnt++;
Expand Down

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