Thanks for your comments Jiayu - please find responses inline.
Thanks,
Mark
From: Hu, Jiayu
>Sent: Friday, September 29, 2017 4:13 AM
>To: Kavanagh, Mark B <mark.b.kavan...@intel.com>
>Cc: dev@dpdk.org; Tan, Jianfeng <jianfeng....@intel.com>; Ananyev, Konstantin
><konstantin.anan...@intel.com>; Yigit, Ferruh <ferruh.yi...@intel.com>;
>tho...@monjalon.net
>Subject: Re: [PATCH v5 2/6] gso: add TCP/IPv4 GSO support
>
>Hi Mark,
>
>One comment is inline.
>
>Thanks,
>Jiayu
>
>On Thu, Sep 28, 2017 at 11:13:49PM +0100, Mark Kavanagh wrote:
>> From: Jiayu Hu <jiayu...@intel.com>
>>
>> This patch adds GSO support for TCP/IPv4 packets. Supported packets
>> may include a single VLAN tag. TCP/IPv4 GSO doesn't check if input
>> packets have correct checksums, and doesn't update checksums for
>> output packets (the responsibility for this lies with the application).
>> Additionally, TCP/IPv4 GSO doesn't process IP fragmented packets.
>>
>> TCP/IPv4 GSO uses two chained MBUFs, one direct MBUF and one indrect
>> MBUF, to organize an output packet. Note that we refer to these two
>> chained MBUFs as a two-segment MBUF. The direct MBUF stores the packet
>> header, while the indirect mbuf simply points to a location within the
>> original packet's payload. Consequently, use of the GSO library requires
>> multi-segment MBUF support in the TX functions of the NIC driver.
>>
>> If a packet is GSO'd, TCP/IPv4 GSO reduces its MBUF refcnt by 1. As a
>> result, when all of its GSOed segments are freed, the packet is freed
>> automatically.
>>
>> Signed-off-by: Jiayu Hu <jiayu...@intel.com>
>> Signed-off-by: Mark Kavanagh <mark.b.kavan...@intel.com>
>> Tested-by: Lei Yao <lei.a....@intel.com>
>> ---
>> doc/guides/rel_notes/release_17_11.rst | 12 +++
>> lib/librte_eal/common/include/rte_log.h | 1 +
>> lib/librte_gso/Makefile | 2 +
>> lib/librte_gso/gso_common.c | 153
>++++++++++++++++++++++++++++++++
>> lib/librte_gso/gso_common.h | 141 +++++++++++++++++++++++++++++
>> lib/librte_gso/gso_tcp4.c | 106 ++++++++++++++++++++++
>> lib/librte_gso/gso_tcp4.h | 74 +++++++++++++++
>> lib/librte_gso/rte_gso.c | 52 ++++++++++-
>> 8 files changed, 538 insertions(+), 3 deletions(-)
>> create mode 100644 lib/librte_gso/gso_common.c
>> create mode 100644 lib/librte_gso/gso_common.h
>> create mode 100644 lib/librte_gso/gso_tcp4.c
>> create mode 100644 lib/librte_gso/gso_tcp4.h
>>
>> diff --git a/doc/guides/rel_notes/release_17_11.rst
>b/doc/guides/rel_notes/release_17_11.rst
>> index 7508be7..c414f73 100644
>> --- a/doc/guides/rel_notes/release_17_11.rst
>> +++ b/doc/guides/rel_notes/release_17_11.rst
>> @@ -41,6 +41,18 @@ New Features
>> Also, make sure to start the actual text at the margin.
>> =========================================================
>>
>> +* **Added the Generic Segmentation Offload Library.**
>> +
>> + Added the Generic Segmentation Offload (GSO) library to enable
>> + applications to split large packets (e.g. MTU is 64KB) into small
>> + ones (e.g. MTU is 1500B). Supported packet types are:
>> +
>> + * TCP/IPv4 packets, which may include a single VLAN tag.
>> +
>> + The GSO library doesn't check if the input packets have correct
>> + checksums, and doesn't update checksums for output packets.
>> + Additionally, the GSO library doesn't process IP fragmented packets.
>> +
>>
>> Resolved Issues
>> ---------------
>> diff --git a/lib/librte_eal/common/include/rte_log.h
>b/lib/librte_eal/common/include/rte_log.h
>> index ec8dba7..2fa1199 100644
>> --- a/lib/librte_eal/common/include/rte_log.h
>> +++ b/lib/librte_eal/common/include/rte_log.h
>> @@ -87,6 +87,7 @@ struct rte_logs {
>> #define RTE_LOGTYPE_CRYPTODEV 17 /**< Log related to cryptodev. */
>> #define RTE_LOGTYPE_EFD 18 /**< Log related to EFD. */
>> #define RTE_LOGTYPE_EVENTDEV 19 /**< Log related to eventdev. */
>> +#define RTE_LOGTYPE_GSO 20 /**< Log related to GSO. */
>>
>> /* these log types can be used in an application */
>> #define RTE_LOGTYPE_USER1 24 /**< User-defined log type 1. */
>> diff --git a/lib/librte_gso/Makefile b/lib/librte_gso/Makefile
>> index aeaacbc..2be64d1 100644
>> --- a/lib/librte_gso/Makefile
>> +++ b/lib/librte_gso/Makefile
>> @@ -42,6 +42,8 @@ LIBABIVER := 1
>>
>> #source files
>> SRCS-$(CONFIG_RTE_LIBRTE_GSO) += rte_gso.c
>> +SRCS-$(CONFIG_RTE_LIBRTE_GSO) += gso_common.c
>> +SRCS-$(CONFIG_RTE_LIBRTE_GSO) += gso_tcp4.c
>>
>> # install this header file
>> SYMLINK-$(CONFIG_RTE_LIBRTE_GSO)-include += rte_gso.h
>> diff --git a/lib/librte_gso/gso_common.c b/lib/librte_gso/gso_common.c
>> new file mode 100644
>> index 0000000..ee75d4c
>> --- /dev/null
>> +++ b/lib/librte_gso/gso_common.c
>> @@ -0,0 +1,153 @@
>> +/*-
>> + * BSD LICENSE
>> + *
>> + * Copyright(c) 2017 Intel Corporation. All rights reserved.
>> + * All rights reserved.
>> + *
>> + * Redistribution and use in source and binary forms, with or without
>> + * modification, are permitted provided that the following conditions
>> + * are met:
>> + *
>> + * * Redistributions of source code must retain the above copyright
>> + * notice, this list of conditions and the following disclaimer.
>> + * * Redistributions in binary form must reproduce the above copyright
>> + * notice, this list of conditions and the following disclaimer in
>> + * the documentation and/or other materials provided with the
>> + * distribution.
>> + * * Neither the name of Intel Corporation nor the names of its
>> + * contributors may be used to endorse or promote products derived
>> + * from this software without specific prior written permission.
>> + *
>> + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
>> + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
>> + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
>> + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
>> + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
>> + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
>> + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
>> + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
>> + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
>> + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
>> + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
>> + */
>> +
>> +#include <stdbool.h>
>> +#include <errno.h>
>> +
>> +#include <rte_memcpy.h>
>> +#include <rte_mempool.h>
>> +
>> +#include "gso_common.h"
>> +
>> +static inline void
>> +hdr_segment_init(struct rte_mbuf *hdr_segment, struct rte_mbuf *pkt,
>> + uint16_t pkt_hdr_offset)
>> +{
>> + /* Copy MBUF metadata */
>> + hdr_segment->nb_segs = 1;
>> + hdr_segment->port = pkt->port;
>> + hdr_segment->ol_flags = pkt->ol_flags;
>> + hdr_segment->packet_type = pkt->packet_type;
>> + hdr_segment->pkt_len = pkt_hdr_offset;
>> + hdr_segment->data_len = pkt_hdr_offset;
>> + hdr_segment->tx_offload = pkt->tx_offload;
>> +
>> + /* Copy the packet header */
>> + rte_memcpy(rte_pktmbuf_mtod(hdr_segment, char *),
>> + rte_pktmbuf_mtod(pkt, char *),
>> + pkt_hdr_offset);
>> +}
>> +
>> +static inline void
>> +free_gso_segment(struct rte_mbuf **pkts, uint16_t nb_pkts)
>> +{
>> + uint16_t i;
>> +
>> + for (i = 0; i < nb_pkts; i++)
>> + rte_pktmbuf_free(pkts[i]);
>> +}
>> +
>> +int
>> +gso_do_segment(struct rte_mbuf *pkt,
>> + uint16_t pkt_hdr_offset,
>> + uint16_t pyld_unit_size,
>> + struct rte_mempool *direct_pool,
>> + struct rte_mempool *indirect_pool,
>> + struct rte_mbuf **pkts_out,
>> + uint16_t nb_pkts_out)
>> +{
>> + struct rte_mbuf *pkt_in;
>> + struct rte_mbuf *hdr_segment, *pyld_segment, *prev_segment;
>> + uint16_t pkt_in_data_pos, segment_bytes_remaining;
>> + uint16_t pyld_len, nb_segs;
>> + bool more_in_pkt, more_out_segs;
>> +
>> + pkt_in = pkt;
>> + nb_segs = 0;
>> + more_in_pkt = 1;
>> + pkt_in_data_pos = pkt_hdr_offset;
>> +
>> + while (more_in_pkt) {
>> + if (unlikely(nb_segs >= nb_pkts_out)) {
>> + free_gso_segment(pkts_out, nb_segs);
>> + return -EINVAL;
>> + }
>> +
>> + /* Allocate a direct MBUF */
>> + hdr_segment = rte_pktmbuf_alloc(direct_pool);
>> + if (unlikely(hdr_segment == NULL)) {
>> + free_gso_segment(pkts_out, nb_segs);
>> + return -ENOMEM;
>> + }
>> + /* Fill the packet header */
>> + hdr_segment_init(hdr_segment, pkt, pkt_hdr_offset);
>> +
>> + prev_segment = hdr_segment;
>> + segment_bytes_remaining = pyld_unit_size;
>> + more_out_segs = 1;
>> +
>> + while (more_out_segs && more_in_pkt) {
>> + /* Allocate an indirect MBUF */
>> + pyld_segment = rte_pktmbuf_alloc(indirect_pool);
>> + if (unlikely(pyld_segment == NULL)) {
>> + rte_pktmbuf_free(hdr_segment);
>> + free_gso_segment(pkts_out, nb_segs);
>> + return -ENOMEM;
>> + }
>> + /* Attach to current MBUF segment of pkt */
>> + rte_pktmbuf_attach(pyld_segment, pkt_in);
>> +
>> + prev_segment->next = pyld_segment;
>> + prev_segment = pyld_segment;
>> +
>> + pyld_len = segment_bytes_remaining;
>> + if (pyld_len + pkt_in_data_pos > pkt_in->data_len)
>> + pyld_len = pkt_in->data_len - pkt_in_data_pos;
>> +
>> + pyld_segment->data_off = pkt_in_data_pos +
>> + pkt_in->data_off;
>> + pyld_segment->data_len = pyld_len;
>> +
>> + /* Update header segment */
>> + hdr_segment->pkt_len += pyld_len;
>> + hdr_segment->nb_segs++;
>> +
>> + pkt_in_data_pos += pyld_len;
>> + segment_bytes_remaining -= pyld_len;
>> +
>> + /* Finish processing a MBUF segment of pkt */
>> + if (pkt_in_data_pos == pkt_in->data_len) {
>> + pkt_in = pkt_in->next;
>> + pkt_in_data_pos = 0;
>> + if (pkt_in == NULL)
>> + more_in_pkt = 0;
>> + }
>> +
>> + /* Finish generating a GSO segment */
>> + if (segment_bytes_remaining == 0)
>> + more_out_segs = 0;
>> + }
>> + pkts_out[nb_segs++] = hdr_segment;
>> + }
>> + return nb_segs;
>> +}
>> diff --git a/lib/librte_gso/gso_common.h b/lib/librte_gso/gso_common.h
>> new file mode 100644
>> index 0000000..8d9b94e
>> --- /dev/null
>> +++ b/lib/librte_gso/gso_common.h
>> @@ -0,0 +1,141 @@
>> +/*-
>> + * BSD LICENSE
>> + *
>> + * Copyright(c) 2017 Intel Corporation. All rights reserved.
>> + * All rights reserved.
>> + *
>> + * Redistribution and use in source and binary forms, with or without
>> + * modification, are permitted provided that the following conditions
>> + * are met:
>> + *
>> + * * Redistributions of source code must retain the above copyright
>> + * notice, this list of conditions and the following disclaimer.
>> + * * Redistributions in binary form must reproduce the above copyright
>> + * notice, this list of conditions and the following disclaimer in
>> + * the documentation and/or other materials provided with the
>> + * distribution.
>> + * * Neither the name of Intel Corporation nor the names of its
>> + * contributors may be used to endorse or promote products derived
>> + * from this software without specific prior written permission.
>> + *
>> + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
>> + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
>> + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
>> + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
>> + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
>> + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
>> + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
>> + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
>> + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
>> + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
>> + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
>> + */
>> +
>> +#ifndef _GSO_COMMON_H_
>> +#define _GSO_COMMON_H_
>> +
>> +#include <stdint.h>
>> +
>> +#include <rte_mbuf.h>
>> +#include <rte_ip.h>
>> +#include <rte_tcp.h>
>> +
>> +#define IS_FRAGMENTED(frag_off) (((frag_off) & IPV4_HDR_OFFSET_MASK) != 0 \
>> + || ((frag_off) & IPV4_HDR_MF_FLAG) == IPV4_HDR_MF_FLAG)
>> +
>> +#define TCP_HDR_PSH_MASK ((uint8_t)0x08)
>> +#define TCP_HDR_FIN_MASK ((uint8_t)0x01)
>> +
>> +#define IS_IPV4_TCP(flag) (((flag) & (PKT_TX_TCP_SEG | PKT_TX_IPV4)) == \
>> + (PKT_TX_TCP_SEG | PKT_TX_IPV4))
>> +
>> +/**
>> + * Internal function which updates the TCP header of a packet, following
>> + * segmentation. This is required to update the header's 'sent' sequence
>> + * number, and also to clear 'PSH' and 'FIN' flags for non-tail segments.
>> + *
>> + * @param pkt
>> + * The packet containing the TCP header.
>> + * @param l4_offset
>> + * The offset of the TCP header from the start of the packet.
>> + * @param sent_seq
>> + * The sent sequence number.
>> + * @param non-tail
>> + * Indicates whether or not this is a tail segment.
>> + */
>> +static inline void
>> +update_tcp_header(struct rte_mbuf *pkt, uint16_t l4_offset, uint32_t
>sent_seq,
>> + uint8_t non_tail)
>> +{
>> + struct tcp_hdr *tcp_hdr;
>> +
>> + tcp_hdr = (struct tcp_hdr *)(rte_pktmbuf_mtod(pkt, char *) +
>> + l4_offset);
>> + tcp_hdr->sent_seq = rte_cpu_to_be_32(sent_seq);
>> + if (likely(non_tail))
>> + tcp_hdr->tcp_flags &= (~(TCP_HDR_PSH_MASK |
>> + TCP_HDR_FIN_MASK));
>> +}
>> +
>> +/**
>> + * Internal function which updates the IPv4 header of a packet, following
>> + * segmentation. This is required to update the header's 'total_length'
>field,
>> + * to reflect the reduced length of the now-segmented packet. Furthermore,
>the
>> + * header's 'packet_id' field must be updated to reflect the new ID of the
>> + * now-segmented packet.
>> + *
>> + * @param pkt
>> + * The packet containing the IPv4 header.
>> + * @param l3_offset
>> + * The offset of the IPv4 header from the start of the packet.
>> + * @param id
>> + * The new ID of the packet.
>> + */
>> +static inline void
>> +update_ipv4_header(struct rte_mbuf *pkt, uint16_t l3_offset, uint16_t id)
>> +{
>> + struct ipv4_hdr *ipv4_hdr;
>> +
>> + ipv4_hdr = (struct ipv4_hdr *)(rte_pktmbuf_mtod(pkt, char *) +
>> + l3_offset);
>> + ipv4_hdr->total_length = rte_cpu_to_be_16(pkt->pkt_len - l3_offset);
>> + ipv4_hdr->packet_id = rte_cpu_to_be_16(id);
>> +}
>> +
>> +/**
>> + * Internal function which divides the input packet into small segments.
>> + * Each of the newly-created segments is organized as a two-segment MBUF,
>> + * where the first segment is a standard mbuf, which stores a copy of
>> + * packet header, and the second is an indirect mbuf which points to a
>> + * section of data in the input packet.
>> + *
>> + * @param pkt
>> + * Packet to segment.
>> + * @param pkt_hdr_offset
>> + * Packet header offset, measured in bytes.
>> + * @param pyld_unit_size
>> + * The max payload length of a GSO segment.
>> + * @param direct_pool
>> + * MBUF pool used for allocating direct buffers for output segments.
>> + * @param indirect_pool
>> + * MBUF pool used for allocating indirect buffers for output segments.
>> + * @param pkts_out
>> + * Pointer array used to keep the mbuf addresses of output segments. If
>> + * the memory space in pkts_out is insufficient, gso_do_segment() fails
>> + * and returns -EINVAL.
>> + * @param nb_pkts_out
>> + * The max number of items that pkts_out can keep.
>> + *
>> + * @return
>> + * - The number of segments created in the event of success.
>> + * - Return -ENOMEM if run out of memory in MBUF pools.
>> + * - Return -EINVAL for invalid parameters.
>> + */
>> +int gso_do_segment(struct rte_mbuf *pkt,
>> + uint16_t pkt_hdr_offset,
>> + uint16_t pyld_unit_size,
>> + struct rte_mempool *direct_pool,
>> + struct rte_mempool *indirect_pool,
>> + struct rte_mbuf **pkts_out,
>> + uint16_t nb_pkts_out);
>> +#endif
>> diff --git a/lib/librte_gso/gso_tcp4.c b/lib/librte_gso/gso_tcp4.c
>> new file mode 100644
>> index 0000000..584a77d
>> --- /dev/null
>> +++ b/lib/librte_gso/gso_tcp4.c
>> @@ -0,0 +1,106 @@
>> +/*-
>> + * BSD LICENSE
>> + *
>> + * Copyright(c) 2017 Intel Corporation. All rights reserved.
>> + * All rights reserved.
>> + *
>> + * Redistribution and use in source and binary forms, with or without
>> + * modification, are permitted provided that the following conditions
>> + * are met:
>> + *
>> + * * Redistributions of source code must retain the above copyright
>> + * notice, this list of conditions and the following disclaimer.
>> + * * Redistributions in binary form must reproduce the above copyright
>> + * notice, this list of conditions and the following disclaimer in
>> + * the documentation and/or other materials provided with the
>> + * distribution.
>> + * * Neither the name of Intel Corporation nor the names of its
>> + * contributors may be used to endorse or promote products derived
>> + * from this software without specific prior written permission.
>> + *
>> + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
>> + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
>> + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
>> + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
>> + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
>> + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
>> + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
>> + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
>> + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
>> + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
>> + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
>> + */
>> +
>> +#include "gso_common.h"
>> +#include "gso_tcp4.h"
>> +
>> +static void
>> +update_ipv4_tcp_headers(struct rte_mbuf *pkt, uint64_t l3_offset,
>> + uint8_t ipid_delta, struct rte_mbuf **segs, uint16_t nb_segs)
>> +{
>
>No need to add "uint64_t l3_offset" as one parameter. We can directly get
>l3_offset inside update_ipv4_tcp_headers().
Yes, of course - thanks Jiayu.
>
>Additionally, the type of l3_offset should be "uint16_t" instead of
>"uint64_t".
That is a rebase artifact - please disregard.
>But if we change the prototype of update_ipv4_tcp_headers(), this issue
>doesn't
>need to fix.
Agreed.
>
>> + struct ipv4_hdr *ipv4_hdr;
>> + struct tcp_hdr *tcp_hdr;
>> + uint32_t sent_seq;
>> + uint16_t id, tail_idx, i;
>> + uint16_t l4_offset;
>> +
>> + ipv4_hdr = (struct ipv4_hdr *)(rte_pktmbuf_mtod(pkt, char*) +
>> + l3_offset);
>> + tcp_hdr = (struct tcp_hdr *)((char *)ipv4_hdr + pkt->l3_len);
>> + id = rte_be_to_cpu_16(ipv4_hdr->packet_id);
>> + sent_seq = rte_be_to_cpu_32(tcp_hdr->sent_seq);
>> + tail_idx = nb_segs - 1;
>> + l4_offset = l3_offset + pkt->l3_len;
>> +
>> + for (i = 0; i < nb_segs; i++) {
>> + update_ipv4_header(segs[i], l3_offset, id);
>> + update_tcp_header(segs[i], l4_offset, sent_seq, i < tail_idx);
>> + id += ipid_delta;
>> + sent_seq += (segs[i]->pkt_len - segs[i]->data_len);
>> + }
>> +}
>> +
>> +int
>> +gso_tcp4_segment(struct rte_mbuf *pkt,
>> + uint16_t gso_size,
>> + uint8_t ipid_delta,
>> + struct rte_mempool *direct_pool,
>> + struct rte_mempool *indirect_pool,
>> + struct rte_mbuf **pkts_out,
>> + uint16_t nb_pkts_out)
>> +{
>> + struct ipv4_hdr *ipv4_hdr;
>> + uint16_t tcp_dl;
>> + uint16_t pyld_unit_size, hdr_offset;
>> + uint16_t frag_off;
>> + int ret;
>> +
>> + /* Don't process the fragmented packet */
>> + ipv4_hdr = (struct ipv4_hdr *)(rte_pktmbuf_mtod(pkt, char *) +
>> + pkt->l2_len);
>> + frag_off = rte_be_to_cpu_16(ipv4_hdr->fragment_offset);
>> + if (unlikely(IS_FRAGMENTED(frag_off))) {
>> + pkts_out[0] = pkt;
>> + return 1;
>> + }
>> +
>> + /* Don't process the packet without data */
>> + tcp_dl = pkt->pkt_len - pkt->l2_len - pkt->l3_len - pkt->l4_len;
>> + if (unlikely(tcp_dl == 0)) {
>> + pkts_out[0] = pkt;
>> + return 1;
>> + }
>> +
>> + hdr_offset = pkt->l2_len + pkt->l3_len + pkt->l4_len;
>> + pyld_unit_size = gso_size - hdr_offset;
>> +
>> + /* Segment the payload */
>> + ret = gso_do_segment(pkt, hdr_offset, pyld_unit_size, direct_pool,
>> + indirect_pool, pkts_out, nb_pkts_out);
>> + if (ret > 1) {
>> + update_ipv4_tcp_headers(pkt, pkt->l2_len, ipid_delta,
>> + pkts_out, ret);
>> + }
>> +
>> + return ret;
>> +}
>> diff --git a/lib/librte_gso/gso_tcp4.h b/lib/librte_gso/gso_tcp4.h
>> new file mode 100644
>> index 0000000..1c57441
>> --- /dev/null
>> +++ b/lib/librte_gso/gso_tcp4.h
>> @@ -0,0 +1,74 @@
>> +/*-
>> + * BSD LICENSE
>> + *
>> + * Copyright(c) 2017 Intel Corporation. All rights reserved.
>> + * All rights reserved.
>> + *
>> + * Redistribution and use in source and binary forms, with or without
>> + * modification, are permitted provided that the following conditions
>> + * are met:
>> + *
>> + * * Redistributions of source code must retain the above copyright
>> + * notice, this list of conditions and the following disclaimer.
>> + * * Redistributions in binary form must reproduce the above copyright
>> + * notice, this list of conditions and the following disclaimer in
>> + * the documentation and/or other materials provided with the
>> + * distribution.
>> + * * Neither the name of Intel Corporation nor the names of its
>> + * contributors may be used to endorse or promote products derived
>> + * from this software without specific prior written permission.
>> + *
>> + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
>> + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
>> + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
>> + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
>> + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
>> + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
>> + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
>> + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
>> + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
>> + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
>> + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
>> + */
>> +
>> +#ifndef _GSO_TCP4_H_
>> +#define _GSO_TCP4_H_
>> +
>> +#include <stdint.h>
>> +#include <rte_mbuf.h>
>> +
>> +/**
>> + * Segment an IPv4/TCP packet. This function doesn't check if the input
>> + * packet has correct checksums, and doesn't update checksums for output
>> + * GSO segments. Furthermore, it doesn't process IP fragment packets.
>> + *
>> + * @param pkt
>> + * The packet mbuf to segment.
>> + * @param gso_size
>> + * The max length of a GSO segment, measured in bytes.
>> + * @param ipid_delta
>> + * The increasing unit of IP ids.
>> + * @param direct_pool
>> + * MBUF pool used for allocating direct buffers for output segments.
>> + * @param indirect_pool
>> + * MBUF pool used for allocating indirect buffers for output segments.
>> + * @param pkts_out
>> + * Pointer array used to store the MBUF addresses of output GSO
>> + * segments, when the function succeeds. If the memory space in
>> + * pkts_out is insufficient, it fails and returns -EINVAL.
>> + * @param nb_pkts_out
>> + * The max number of items that 'pkts_out' can keep.
>> + *
>> + * @return
>> + * - The number of GSO segments filled in pkts_out on success.
>> + * - Return -ENOMEM if run out of memory in MBUF pools.
>> + * - Return -EINVAL for invalid parameters.
>> + */
>> +int gso_tcp4_segment(struct rte_mbuf *pkt,
>> + uint16_t gso_size,
>> + uint8_t ip_delta,
>> + struct rte_mempool *direct_pool,
>> + struct rte_mempool *indirect_pool,
>> + struct rte_mbuf **pkts_out,
>> + uint16_t nb_pkts_out);
>> +#endif
>> diff --git a/lib/librte_gso/rte_gso.c b/lib/librte_gso/rte_gso.c
>> index b773636..a4fce50 100644
>> --- a/lib/librte_gso/rte_gso.c
>> +++ b/lib/librte_gso/rte_gso.c
>> @@ -33,7 +33,12 @@
>>
>> #include <errno.h>
>>
>> +#include <rte_log.h>
>> +#include <rte_ethdev.h>
>> +
>> #include "rte_gso.h"
>> +#include "gso_common.h"
>> +#include "gso_tcp4.h"
>>
>> int
>> rte_gso_segment(struct rte_mbuf *pkt,
>> @@ -41,12 +46,53 @@
>> struct rte_mbuf **pkts_out,
>> uint16_t nb_pkts_out)
>> {
>> + struct rte_mempool *direct_pool, *indirect_pool;
>> + struct rte_mbuf *pkt_seg;
>> + uint64_t ol_flags;
>> + uint16_t gso_size;
>> + uint8_t ipid_delta;
>> + int ret = 1;
>> +
>> if (pkt == NULL || pkts_out == NULL || gso_ctx == NULL ||
>> nb_pkts_out < 1)
>> return -EINVAL;
>>
>> - pkt->ol_flags &= (~PKT_TX_TCP_SEG);
>> - pkts_out[0] = pkt;
>> + if ((gso_ctx->gso_size >= pkt->pkt_len) || (gso_ctx->gso_types &
>> + DEV_TX_OFFLOAD_TCP_TSO) !=
>> + gso_ctx->gso_types) {
>> + pkt->ol_flags &= (~PKT_TX_TCP_SEG);
>> + pkts_out[0] = pkt;
>> + return 1;
>> + }
>> +
>> + direct_pool = gso_ctx->direct_pool;
>> + indirect_pool = gso_ctx->indirect_pool;
>> + gso_size = gso_ctx->gso_size;
>> + ipid_delta = (gso_ctx->ipid_flag != RTE_GSO_IPID_FIXED);
>> + ol_flags = pkt->ol_flags;
>> +
>> + if (IS_IPV4_TCP(pkt->ol_flags)) {
>> + pkt->ol_flags &= (~PKT_TX_TCP_SEG);
>> + ret = gso_tcp4_segment(pkt, gso_size, ipid_delta,
>> + direct_pool, indirect_pool,
>> + pkts_out, nb_pkts_out);
>> + } else {
>> + pkt->ol_flags &= (~PKT_TX_TCP_SEG);
>> + pkts_out[0] = pkt;
>> + RTE_LOG(WARNING, GSO, "Unsupported packet type\n");
>> + return 1;
>> + }
>> +
>> + if (ret > 1) {
>> + pkt_seg = pkt;
>> + while (pkt_seg) {
>> + rte_mbuf_refcnt_update(pkt_seg, -1);
>> + pkt_seg = pkt_seg->next;
>> + }
>> + } else if (ret < 0) {
>> + /* Revert the ol_flags in the event of failure. */
>> + pkt->ol_flags = ol_flags;
>> + }
>>
>> - return 1;
>> + return ret;
>> }
>> --
>> 1.9.3
