rte_gso_segment decreased refcnt of pkt by one, but
it is wrong if pkt is external mbuf, pkt won't be
freed because of incorrect refcnt, the result is
application can't allocate mbuf from mempool because
mbufs in mempool are run out of.
One correct way is application should call
rte_pktmbuf_free after calling rte_gso_segment to free
pkt explicitly. rte_gso_segment must not handle it, this
should be responsibility of application.
This commit changed rte_gso_segment in functional behavior
and return value, so the application must take appropriate
actions according to return values, "ret < 0" means it
should free and drop 'pkt', "ret == 0" means 'pkt' isn't
GSOed but 'pkt' can be transmitted as a normal packet,
"ret > 0" means 'pkt' has been GSOed into two or multiple
segments, it should use "pkts_out" to transmit these
segments. The application must free 'pkt' after call
rte_gso_segment when return value isn't equal to 0.
Fixes: 119583797b ("gso: support TCP/IPv4 GSO")
Cc: stable@dpdk.org
Signed-off-by: Yi Yang <yangyi01@inspur.com>
Acked-by: Jiayu Hu <jiayu.hu@intel.com>
Acked-by: Konstantin Ananyev <konstantin.ananyev@intel.com>
Replace the BSD license header with the SPDX tag for files
with only an Intel copyright on them.
Signed-off-by: Bruce Richardson <bruce.richardson@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.hu@intel.com>
Signed-off-by: Mark Kavanagh <mark.b.kavanagh@intel.com>
Acked-by: Konstantin Ananyev <konstantin.ananyev@intel.com>
Tested-by: Lei Yao <lei.a.yao@intel.com>