2.6.30-stable review patch. If anyone has any objections, please let us know. ------------------ From: Ajit Khaparde [ Upstream commit bd46cb6cf11867130a41ea9546dd65688b71f3c2 ] While testing the driver on PPC, we ran into a crash with LRO, Jumbo frames. With CONFIG_PPC_64K_PAGES configured (a default in PPC), MAX_SKB_FRAGS drops to 3 and we were crossing the array limits on skb_shinfo(skb)->frags[]. Now we coalesce the frags from the same physical page into one slot in skb_shinfo(skb)->frags[] and go to the next index when the frag is from different physical page. This patch is against the net-2.6 tree. Signed-off-by: Ajit Khaparde Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- drivers/net/benet/be.h | 2 - drivers/net/benet/be_ethtool.c | 4 +-- drivers/net/benet/be_main.c | 45 +++++++++++++++++++++++++++++------------ 3 files changed, 35 insertions(+), 16 deletions(-) --- a/drivers/net/benet/be_ethtool.c +++ b/drivers/net/benet/be_ethtool.c @@ -162,8 +162,8 @@ be_set_coalesce(struct net_device *netde return -EINVAL; adapter->max_rx_coal = coalesce->rx_max_coalesced_frames; - if (adapter->max_rx_coal > MAX_SKB_FRAGS) - adapter->max_rx_coal = MAX_SKB_FRAGS - 1; + if (adapter->max_rx_coal > BE_MAX_FRAGS_PER_FRAME) + adapter->max_rx_coal = BE_MAX_FRAGS_PER_FRAME; /* if AIC is being turned on now, start with an EQD of 0 */ if (rx_eq->enable_aic == 0 && --- a/drivers/net/benet/be.h +++ b/drivers/net/benet/be.h @@ -73,7 +73,7 @@ static inline char *nic_name(struct pci_ #define RX_FRAGS_REFILL_WM (RX_Q_LEN - MAX_RX_POST) #define BE_MAX_LRO_DESCRIPTORS 16 -#define BE_MAX_FRAGS_PER_FRAME 16 +#define BE_MAX_FRAGS_PER_FRAME (min((u32) 16, (u32) MAX_SKB_FRAGS)) struct be_dma_mem { void *va; --- a/drivers/net/benet/be_main.c +++ b/drivers/net/benet/be_main.c @@ -682,7 +682,7 @@ static void skb_fill_rx_data(struct be_a { struct be_queue_info *rxq = &adapter->rx_obj.q; struct be_rx_page_info *page_info; - u16 rxq_idx, i, num_rcvd; + u16 rxq_idx, i, num_rcvd, j; u32 pktsize, hdr_len, curr_frag_len; u8 *start; @@ -725,22 +725,33 @@ static void skb_fill_rx_data(struct be_a /* More frags present for this completion */ pktsize -= curr_frag_len; /* account for above copied frag */ - for (i = 1; i < num_rcvd; i++) { + for (i = 1, j = 0; i < num_rcvd; i++) { index_inc(&rxq_idx, rxq->len); page_info = get_rx_page_info(adapter, rxq_idx); curr_frag_len = min(pktsize, rx_frag_size); - skb_shinfo(skb)->frags[i].page = page_info->page; - skb_shinfo(skb)->frags[i].page_offset = page_info->page_offset; - skb_shinfo(skb)->frags[i].size = curr_frag_len; + /* Coalesce all frags from the same physical page in one slot */ + if (page_info->page_offset == 0) { + /* Fresh page */ + j++; + skb_shinfo(skb)->frags[j].page = page_info->page; + skb_shinfo(skb)->frags[j].page_offset = + page_info->page_offset; + skb_shinfo(skb)->frags[j].size = 0; + skb_shinfo(skb)->nr_frags++; + } else { + put_page(page_info->page); + } + + skb_shinfo(skb)->frags[j].size += curr_frag_len; skb->len += curr_frag_len; skb->data_len += curr_frag_len; - skb_shinfo(skb)->nr_frags++; pktsize -= curr_frag_len; memset(page_info, 0, sizeof(*page_info)); } + BUG_ON(j > MAX_SKB_FRAGS); be_rx_stats_update(adapter, pktsize, num_rcvd); return; @@ -803,7 +814,7 @@ static void be_rx_compl_process_lro(stru struct skb_frag_struct rx_frags[BE_MAX_FRAGS_PER_FRAME]; struct be_queue_info *rxq = &adapter->rx_obj.q; u32 num_rcvd, pkt_size, remaining, vlanf, curr_frag_len; - u16 i, rxq_idx = 0, vid; + u16 i, rxq_idx = 0, vid, j; num_rcvd = AMAP_GET_BITS(struct amap_eth_rx_compl, numfrags, rxcp); pkt_size = AMAP_GET_BITS(struct amap_eth_rx_compl, pktsize, rxcp); @@ -811,20 +822,28 @@ static void be_rx_compl_process_lro(stru rxq_idx = AMAP_GET_BITS(struct amap_eth_rx_compl, fragndx, rxcp); remaining = pkt_size; - for (i = 0; i < num_rcvd; i++) { + for (i = 0, j = -1; i < num_rcvd; i++) { page_info = get_rx_page_info(adapter, rxq_idx); curr_frag_len = min(remaining, rx_frag_size); - rx_frags[i].page = page_info->page; - rx_frags[i].page_offset = page_info->page_offset; - rx_frags[i].size = curr_frag_len; - remaining -= curr_frag_len; + /* Coalesce all frags from the same physical page in one slot */ + if (i == 0 || page_info->page_offset == 0) { + /* First frag or Fresh page */ + j++; + rx_frags[j].page = page_info->page; + rx_frags[j].page_offset = page_info->page_offset; + rx_frags[j].size = 0; + } else { + put_page(page_info->page); + } + rx_frags[j].size += curr_frag_len; + remaining -= curr_frag_len; index_inc(&rxq_idx, rxq->len); - memset(page_info, 0, sizeof(*page_info)); } + BUG_ON(j > MAX_SKB_FRAGS); if (likely(!vlanf)) { lro_receive_frags(&adapter->rx_obj.lro_mgr, rx_frags, pkt_size, -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/