From: Brice Goglin Date: Mon, 11 Dec 2006 10:25:09 +0000 (+0100) Subject: [PATCH] myri10ge: add page-based skb routines X-Git-Tag: v2.6.20-rc1~146^2~25^2~6 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=dd50f3361f9f0bb407658e9087947c9bdcdefffc;p=linux-2.6 [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: Brice Goglin Signed-off-by: Jeff Garzik --- diff --git a/drivers/net/myri10ge/myri10ge.c b/drivers/net/myri10ge/myri10ge.c index 1e62f58ed2..05b4f93518 100644 --- a/drivers/net/myri10ge/myri10ge.c +++ b/drivers/net/myri10ge/myri10ge.c @@ -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)