From 51e8439f34962794f6c5010a44893fe58450b8df Mon Sep 17 00:00:00 2001 From: Peng Li Date: Sun, 27 Jan 2019 00:49:19 +0800 Subject: [PATCH] net: hns3: add 8 BD limit for tx flow A single transmit packet can span up to 8 descriptors according to the HW limit. If a skb has more than 8 frags, driver uses skb_copy to get a new skb which has less frags. Signed-off-by: Peng Li Signed-off-by: Huazhong Tan Signed-off-by: David S. Miller --- drivers/net/ethernet/hisilicon/hns3/hns3_enet.c | 28 ++++++++++++++++++++++++- 1 file changed, 27 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c b/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c index 93e3e38ba852..216f3dd25cd6 100644 --- a/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c +++ b/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c @@ -1133,6 +1133,7 @@ static int hns3_nic_maybe_stop_tso(struct sk_buff **out_skb, int *bnum, struct hns3_enet_ring *ring) { struct sk_buff *skb = *out_skb; + struct sk_buff *new_skb = NULL; struct skb_frag_struct *frag; int bdnum_for_frag; int frag_num; @@ -1155,7 +1156,19 @@ static int hns3_nic_maybe_stop_tso(struct sk_buff **out_skb, int *bnum, buf_num += bdnum_for_frag; } - if (buf_num > ring_space(ring)) + if (unlikely(buf_num > HNS3_MAX_BD_PER_FRAG)) { + buf_num = (skb->len + HNS3_MAX_BD_SIZE - 1) / HNS3_MAX_BD_SIZE; + if (ring_space(ring) < buf_num) + return -EBUSY; + /* manual split the send packet */ + new_skb = skb_copy(skb, GFP_ATOMIC); + if (!new_skb) + return -ENOMEM; + dev_kfree_skb_any(skb); + *out_skb = new_skb; + } + + if (unlikely(ring_space(ring) < buf_num)) return -EBUSY; *bnum = buf_num; @@ -1166,11 +1179,24 @@ static int hns3_nic_maybe_stop_tx(struct sk_buff **out_skb, int *bnum, struct hns3_enet_ring *ring) { struct sk_buff *skb = *out_skb; + struct sk_buff *new_skb = NULL; int buf_num; /* No. of segments (plus a header) */ buf_num = skb_shinfo(skb)->nr_frags + 1; + if (unlikely(buf_num > HNS3_MAX_BD_PER_FRAG)) { + buf_num = (skb->len + HNS3_MAX_BD_SIZE - 1) / HNS3_MAX_BD_SIZE; + if (ring_space(ring) < buf_num) + return -EBUSY; + /* manual split the send packet */ + new_skb = skb_copy(skb, GFP_ATOMIC); + if (!new_skb) + return -ENOMEM; + dev_kfree_skb_any(skb); + *out_skb = new_skb; + } + if (unlikely(ring_space(ring) < buf_num)) return -EBUSY; -- 2.11.0