Commit dd50f336 authored by Brice Goglin's avatar Brice Goglin Committed by Jeff Garzik
Browse files

[PATCH] myri10ge: add page-based skb routines 



Add physical page skb allocation routines and page based rx_done,
to be used by upcoming patches.

Signed-off-by: default avatarBrice Goglin <brice@myri.com>
Signed-off-by: default avatarJeff Garzik <jeff@garzik.org>
parent 6250223e

drivers/net/myri10ge/myri10ge.c

+190 −0
Original line number Diff line number Diff line
@@ -92,8 +92,14 @@ MODULE_LICENSE("Dual BSD/GPL"); 
#define MYRI10GE_NO_CONFIRM_DATA htonl(0xffffffff)

#define MYRI10GE_NO_RESPONSE_RESULT 0xffffffff



#define MYRI10GE_ALLOC_ORDER 0

#define MYRI10GE_ALLOC_SIZE ((1 << MYRI10GE_ALLOC_ORDER) * PAGE_SIZE)

#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)

	 DECLARE_PCI_UNMAP_LEN(len)

};
@@ -116,9 +122,14 @@ struct myri10ge_rx_buf { 
	u8 __iomem *wc_fifo;	/* w/c rx dma addr fifo address */

	struct mcp_kreq_ether_recv *shadow;	/* host shadow of recv ring */

	struct myri10ge_rx_buffer_state *info;

	struct page *page;

	dma_addr_t bus;

	int page_offset;

	int cnt;

	int fill_cnt;

	int alloc_fail;

	int mask;		/* number of rx slots -1 */

	int watchdog_needed;

};



struct myri10ge_tx_buf {
@@ -150,6 +161,7 @@ struct myri10ge_priv { 
	struct myri10ge_rx_buf rx_big;

	struct myri10ge_rx_done rx_done;

	int small_bytes;

	int big_bytes;

	struct net_device *dev;

	struct net_device_stats stats;

	u8 __iomem *sram;
@@ -266,6 +278,10 @@ static int myri10ge_debug = -1; /* defaults above */ 
module_param(myri10ge_debug, int, 0);

MODULE_PARM_DESC(myri10ge_debug, "Debug level (0=none,...,16=all)");



static int myri10ge_fill_thresh = 256;

module_param(myri10ge_fill_thresh, int, S_IRUGO | S_IWUSR);

MODULE_PARM_DESC(myri10ge_fill_thresh, "Number of empty rx slots allowed\n");



#define MYRI10GE_FW_OFFSET 1024*1024

#define MYRI10GE_HIGHPART_TO_U32(X) \

(sizeof (X) == 8) ? ((u32)((u64)(X) >> 32)) : (0)
@@ -958,6 +974,180 @@ static inline void myri10ge_vlan_ip_csum(struct sk_buff *skb, __wsum hw_csum) 
	}

}



static inline void

myri10ge_rx_skb_build(struct sk_buff *skb, u8 * va,

		      struct skb_frag_struct *rx_frags, int len, int hlen)

{

	struct skb_frag_struct *skb_frags;



	skb->len = skb->data_len = len;

	skb->truesize = len + sizeof(struct sk_buff);

	/* attach the page(s) */



	skb_frags = skb_shinfo(skb)->frags;

	while (len > 0) {

		memcpy(skb_frags, rx_frags, sizeof(*skb_frags));

		len -= rx_frags->size;

		skb_frags++;

		rx_frags++;

		skb_shinfo(skb)->nr_frags++;

	}



	/* pskb_may_pull is not available in irq context, but

	 * skb_pull() (for ether_pad and eth_type_trans()) requires

	 * the beginning of the packet in skb_headlen(), move it

	 * manually */

	memcpy(skb->data, va, hlen);

	skb_shinfo(skb)->frags[0].page_offset += hlen;

	skb_shinfo(skb)->frags[0].size -= hlen;

	skb->data_len -= hlen;

	skb->tail += hlen;

	skb_pull(skb, MXGEFW_PAD);

}



static void

myri10ge_alloc_rx_pages(struct myri10ge_priv *mgp, struct myri10ge_rx_buf *rx,

			int bytes, int watchdog)

{

	struct page *page;

	int idx;



	if (unlikely(rx->watchdog_needed && !watchdog))

		return;



	/* try to refill entire ring */

	while (rx->fill_cnt != (rx->cnt + rx->mask + 1)) {

		idx = rx->fill_cnt & rx->mask;



		if ((bytes < MYRI10GE_ALLOC_SIZE / 2) &&

		    (rx->page_offset + bytes <= MYRI10GE_ALLOC_SIZE)) {

			/* we can use part of previous page */

			get_page(rx->page);

		} else {

			/* we need a new page */

			page =

			    alloc_pages(GFP_ATOMIC | __GFP_COMP,

					MYRI10GE_ALLOC_ORDER);

			if (unlikely(page == NULL)) {

				if (rx->fill_cnt - rx->cnt < 16)

					rx->watchdog_needed = 1;

				return;

			}

			rx->page = page;

			rx->page_offset = 0;

			rx->bus = pci_map_page(mgp->pdev, page, 0,

					       MYRI10GE_ALLOC_SIZE,

					       PCI_DMA_FROMDEVICE);

		}

		rx->info[idx].page = rx->page;

		rx->info[idx].page_offset = rx->page_offset;

		/* note that this is the address of the start of the

		 * page */

		pci_unmap_addr_set(&rx->info[idx], bus, rx->bus);

		rx->shadow[idx].addr_low =

		    htonl(MYRI10GE_LOWPART_TO_U32(rx->bus) + rx->page_offset);

		rx->shadow[idx].addr_high =

		    htonl(MYRI10GE_HIGHPART_TO_U32(rx->bus));



		/* start next packet on a cacheline boundary */

		rx->page_offset += SKB_DATA_ALIGN(bytes);

		rx->fill_cnt++;



		/* copy 8 descriptors to the firmware 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);

			}

		}

	}

}



static inline void

myri10ge_unmap_rx_page(struct pci_dev *pdev,

		       struct myri10ge_rx_buffer_state *info, int bytes)

{

	/* unmap the recvd page if we're the only or last user of it */

	if (bytes >= MYRI10GE_ALLOC_SIZE / 2 ||

	    (info->page_offset + 2 * bytes) > MYRI10GE_ALLOC_SIZE) {

		pci_unmap_page(pdev, (pci_unmap_addr(info, bus)

				      & ~(MYRI10GE_ALLOC_SIZE - 1)),

			       MYRI10GE_ALLOC_SIZE, PCI_DMA_FROMDEVICE);

	}

}



#define MYRI10GE_HLEN 64	/* The number of bytes to copy from a

				 * 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)

{

	struct sk_buff *skb;

	struct skb_frag_struct rx_frags[MYRI10GE_MAX_FRAGS_PER_FRAME];

	int i, idx, hlen, remainder;

	struct pci_dev *pdev = mgp->pdev;

	struct net_device *dev = mgp->dev;

	u8 *va;



	len += MXGEFW_PAD;

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

	va = page_address(rx->info[idx].page) + rx->info[idx].page_offset;

	prefetch(va);

	/* Fill skb_frag_struct(s) with data from our receive */

	for (i = 0, remainder = len; remainder > 0; i++) {

		myri10ge_unmap_rx_page(pdev, &rx->info[idx], bytes);

		rx_frags[i].page = rx->info[idx].page;

		rx_frags[i].page_offset = rx->info[idx].page_offset;

		if (remainder < MYRI10GE_ALLOC_SIZE)

			rx_frags[i].size = remainder;

		else

			rx_frags[i].size = MYRI10GE_ALLOC_SIZE;

		rx->cnt++;

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

		remainder -= MYRI10GE_ALLOC_SIZE;

	}



	hlen = MYRI10GE_HLEN > len ? len : MYRI10GE_HLEN;



	/* allocate an skb to attach the page(s) to. */



	skb = netdev_alloc_skb(dev, MYRI10GE_HLEN + 16);

	if (unlikely(skb == NULL)) {

		mgp->stats.rx_dropped++;

		do {

			i--;

			put_page(rx_frags[i].page);

		} while (i != 0);

		return 0;

	}



	/* Attach the pages to the skb, and trim off any padding */

	myri10ge_rx_skb_build(skb, va, rx_frags, len, hlen);

	if (skb_shinfo(skb)->frags[0].size <= 0) {

		put_page(skb_shinfo(skb)->frags[0].page);

		skb_shinfo(skb)->nr_frags = 0;

	}

	skb->protocol = eth_type_trans(skb, dev);

	skb->dev = 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);

	dev->last_rx = jiffies;

	return 1;

}



static inline unsigned long

myri10ge_rx_done(struct myri10ge_priv *mgp, struct myri10ge_rx_buf *rx,

		 int bytes, int len, __wsum csum)