> From: huichao cai <chcch...@163.com>
>
> According to RFC791,the fragment offset value should be
> calculated based on the long datagram,the more fragments flag
> for the last fragment carries the same value as the long datagram.
Have to admit, that commit log is really cryptic.
I couldn't figure out what it is about till I read the actual code.
As I understand what that patch does - fixes the case when we have
to fragment already fragmented ip datagram, correct?
The code changes itself look ok to me.
Can I ask you to do few things:
1. Reword commit message, it is really misleading right now.
Also if is a fix, then you need to follow:
https://doc.dpdk.org/guides/contributing/patches.html#patch-fix-related-issues
2. Add new test-case for it into app/test/test_ipfrag.c
Thanks
>
> Signed-off-by: huichao cai <chcch...@163.com>
> ---
> lib/ip_frag/rte_ipv4_fragmentation.c | 9 ++++++---
> 1 file changed, 6 insertions(+), 3 deletions(-)
>
> diff --git a/lib/ip_frag/rte_ipv4_fragmentation.c
> b/lib/ip_frag/rte_ipv4_fragmentation.c
> index 2e7739d..fead5a9 100644
> --- a/lib/ip_frag/rte_ipv4_fragmentation.c
> +++ b/lib/ip_frag/rte_ipv4_fragmentation.c
> @@ -75,7 +75,7 @@ static inline void __free_fragments(struct rte_mbuf *mb[],
> uint32_t num)
> uint32_t out_pkt_pos, in_seg_data_pos;
> uint32_t more_in_segs;
> uint16_t fragment_offset, flag_offset, frag_size, header_len;
> - uint16_t frag_bytes_remaining;
> + uint16_t frag_bytes_remaining, not_last_frag;
>
> /*
> * Formal parameter checking.
> @@ -116,7 +116,9 @@ static inline void __free_fragments(struct rte_mbuf
> *mb[], uint32_t num)
> in_seg = pkt_in;
> in_seg_data_pos = header_len;
> out_pkt_pos = 0;
> - fragment_offset = 0;
> + fragment_offset = (uint16_t)((flag_offset &
> + RTE_IPV4_HDR_OFFSET_MASK) << RTE_IPV4_HDR_FO_SHIFT);
> + not_last_frag = (uint16_t)(flag_offset & IPV4_HDR_MF_MASK);
>
> more_in_segs = 1;
> while (likely(more_in_segs)) {
> @@ -186,7 +188,8 @@ static inline void __free_fragments(struct rte_mbuf
> *mb[], uint32_t num)
>
> __fill_ipv4hdr_frag(out_hdr, in_hdr, header_len,
> (uint16_t)out_pkt->pkt_len,
> - flag_offset, fragment_offset, more_in_segs);
> + flag_offset, fragment_offset,
> + not_last_frag || more_in_segs);
>
> fragment_offset = (uint16_t)(fragment_offset +
> out_pkt->pkt_len - header_len);
> --
> 1.8.3.1
