124 Commits

Author SHA1 Message Date
Marvin Liu
aa74c383d4 vhost: fix batch enqueue only handle few packets
After enqueue function finished, packet index has been increased. Batch
enqueue function should retrieve mbuf structure pointed by that index.

Fixes: 0294211bb6dc ("vhost: optimize packed ring enqueue")

Signed-off-by: Marvin Liu <yong.liu@intel.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
2019-11-08 23:15:05 +01:00
Marvin Liu
4da3dd4885 vhost: fix dirty page logging missing
Packets data are directly copied when doing batch enqueue, add missed
dirty page logging after memory copy.

Fixes: ef861692c398 ("vhost: add packed ring batch enqueue")

Signed-off-by: Marvin Liu <yong.liu@intel.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
2019-11-08 23:15:05 +01:00
Flavio Leitner
84c39beb2f vhost: fix IPv4 checksum
Currently the IPv4 header checksum is calculated including its
current value, which can be a valid checksum or just garbage.
In any case, if the original value is not zero, then the result
is always wrong.

The IPv4 checksum is defined in RFC791, page 14 says:
  Header Checksum:  16 bits

  The checksum algorithm is:
  The checksum field is the 16 bit one's complement of the one's
  complement sum of all 16 bit words in the header.  For purposes of
  computing the checksum, the value of the checksum field is zero.

Thus force the csum field to always be zero.

Fixes: b08b8cfeb2ae ("vhost: fix IP checksum")
Cc: stable@dpdk.org

Signed-off-by: Flavio Leitner <fbl@sysclose.org>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
2019-10-25 19:23:22 +02:00
Ilya Maximets
19896c7393 vhost: return error message for mbuf allocation failure
mbuf allocation failure is a hard failure that highlights some
significant issues with memory pool size or a mbuf leak.

We still have the message for subsequent chained mbufs, but not
for the first one.  It was removed while introducing extbuf
support for large buffers.  But it was useful for catching
mempool issues and needs to be returned back.

Fixes: c3ff0ac70acb ("vhost: improve performance by supporting large buffer")

Signed-off-by: Ilya Maximets <i.maximets@ovn.org>
Reviewed-by: Flavio Leitner <fbl@sysclose.org>
Reviewed-by: Tiwei Bie <tiwei.bie@intel.com>
2019-10-25 19:22:46 +02:00
Marvin Liu
f974ca7a29 vhost: optimize packed ring dequeue when in-order
When VIRTIO_F_IN_ORDER feature is negotiated, vhost can optimize dequeue
function by only update first used descriptor.

Signed-off-by: Marvin Liu <yong.liu@intel.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
2019-10-25 19:20:47 +02:00
Marvin Liu
31d6c6a5b8 vhost: optimize packed ring dequeue
Optimize vhost device packed ring dequeue function by splitting batch
and single functions. No-chained and direct descriptors will be handled
by batch and other will be handled by single as before.

Signed-off-by: Marvin Liu <yong.liu@intel.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
2019-10-25 19:20:47 +02:00
Marvin Liu
d1eafb5322 vhost: add packed ring zcopy batch and single dequeue
Add vhost packed ring zero copy batch and single dequeue functions like
normal dequeue path.

Signed-off-by: Marvin Liu <yong.liu@intel.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
2019-10-25 19:20:47 +02:00
Marvin Liu
0294211bb6 vhost: optimize packed ring enqueue
Optimize vhost device packed ring enqueue function by splitting batch
and single functions. Packets can be filled into one desc will be
handled by batch and others will be handled by single as before.

Signed-off-by: Marvin Liu <yong.liu@intel.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
2019-10-25 19:20:47 +02:00
Marvin Liu
c119edbc2d vhost: update packed ring dequeue
Buffer used ring updates as many as possible in vhost dequeue function
for coordinating with virtio driver. For supporting buffer, shadow used
ring element should contain descriptor's flags. First shadowed ring
index was recorded for calculating buffered number.

Signed-off-by: Marvin Liu <yong.liu@intel.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
2019-10-25 19:20:47 +02:00
Marvin Liu
f41516c309 vhost: flush batched enqueue descs directly
Flush used elements when batched enqueue function is finished.
Descriptor's flags are pre-calculated as they will be reset by vhost.

Signed-off-by: Marvin Liu <yong.liu@intel.com>
Reviewed-by: Gavin Hu <gavin.hu@arm.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
2019-10-25 19:20:47 +02:00
Marvin Liu
33d4a554f9 vhost: flush enqueue updates by cacheline
Buffer vhost packed ring enqueue updates, flush ring descs if buffered
content filled up one cacheline. Thus virtio can receive packets at a
faster frequency.

Signed-off-by: Marvin Liu <yong.liu@intel.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
2019-10-25 19:20:47 +02:00
Marvin Liu
75ed516978 vhost: add packed ring batch dequeue
Add batch dequeue function like enqueue function for packed ring, batch
dequeue function will not support chained descriptors, single packet
dequeue function will handle it.

Signed-off-by: Marvin Liu <yong.liu@intel.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
2019-10-25 19:20:47 +02:00
Marvin Liu
47ac243ac4 vhost: add packed ring single dequeue
Add vhost single packet dequeue function for packed ring and meanwhile
left space for shadow used ring update function.

Signed-off-by: Marvin Liu <yong.liu@intel.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
2019-10-25 19:20:47 +02:00
Marvin Liu
ef861692c3 vhost: add packed ring batch enqueue
Batch enqueue function will first check whether descriptors are cache
aligned. It will also check prerequisites in the beginning. Batch
enqueue function do not support chained mbufs, single packet enqueue
function will handle it.

Signed-off-by: Marvin Liu <yong.liu@intel.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
2019-10-25 19:20:47 +02:00
Marvin Liu
93520085ef vhost: add packed ring single enqueue
Add vhost enqueue function for single packet and meanwhile left space
for flush used ring function.

Signed-off-by: Marvin Liu <yong.liu@intel.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
2019-10-25 19:20:47 +02:00
Marvin Liu
86202aae94 vhost: add packed ring indexes increasing function
When enqueuing or dequeuing, the virtqueue's local available and used
indexes are increased.

Signed-off-by: Marvin Liu <yong.liu@intel.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
2019-10-25 19:20:47 +02:00
Flavio Leitner
c3ff0ac70a vhost: improve performance by supporting large buffer
The rte_vhost_dequeue_burst supports two ways of dequeuing data.
If the data fits into a buffer, then all data is copied and a
single linear buffer is returned. Otherwise it allocates
additional mbufs and chains them together to return a multiple
segments mbuf.

While that covers most use cases, it forces applications that
need to work with larger data sizes to support multiple segments
mbufs. The non-linear characteristic brings complexity and
performance implications to the application.

To resolve the issue, add support to attach external buffer
to a pktmbuf and let the host provide during registration if
attaching an external buffer to pktmbuf is supported and if
only linear buffer are supported.

Signed-off-by: Flavio Leitner <fbl@sysclose.org>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
2019-10-23 16:43:09 +02:00
Adrian Moreno
1fc3b3f06a vhost: convert buffer addresses to GPA for logging
Add IOVA versions of dirty page logging functions.

Note that the API facing rte_vhost_log_write is not modified.
So, make explicit that it expects the address in GPA space.

Fixes: 69c90e98f483 ("vhost: enable IOMMU support")
Cc: stable@dpdk.org

Signed-off-by: Adrian Moreno <amorenoz@redhat.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
2019-10-23 16:43:09 +02:00
Joyce Kong
2c661d418e net/virtio: improve perf via one-way barriers on used flag
In case VIRTIO_F_ORDER_PLATFORM(36) is not negotiated, then the frontend
and backend are assumed to be implemented in software, that is they can
run on identical CPUs in an SMP configuration.
Thus a weak form of memory barriers like rte_smp_r/wmb, other than
rte_cio_r/wmb, is sufficient for this case(vq->hw->weak_barriers == 1)
and yields better performance.
For the above case, this patch helps yielding even better performance
by replacing the two-way barriers with C11 one-way barriers for used
flags in packed ring.

Signed-off-by: Joyce Kong <joyce.kong@arm.com>
Reviewed-by: Gavin Hu <gavin.hu@arm.com>
Reviewed-by: Phil Yang <phil.yang@arm.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
2019-10-23 16:43:09 +02:00
Joyce Kong
6094557de0 net/virtio: improve perf via one-way barrier on avail flag
In case VIRTIO_F_ORDER_PLATFORM(36) is not negotiated, then the frontend
and backend are assumed to be implemented in software, that is they can
run on identical CPUs in an SMP configuration.
Thus a weak form of memory barriers like rte_smp_r/wmb, other than
rte_cio_r/wmb, is sufficient for this case(vq->hw->weak_barriers == 1)
and yields better performance.
For the above case, this patch helps yielding even better performance
by replacing the two-way barriers with C11 one-way barriers for avail
flags in packed ring.

Meanwhile, a read barrier is required to ensure ordering between
descriptor's flags and content reads [1]. With C11, load-acquire can
enforce the ordering instead of rmb barrier.

[1] https://patchwork.dpdk.org/patch/49109/

Signed-off-by: Joyce Kong <joyce.kong@arm.com>
Reviewed-by: Gavin Hu <gavin.hu@arm.com>
Reviewed-by: Phil Yang <phil.yang@arm.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
2019-10-23 16:43:09 +02:00
Maxime Coquelin
d1134c09e3 vhost: simplify descriptor buffer prefetching
Now that we have a single function to map the descriptors
buffers, let's prefetch them there as it is the earliest
place we can do it.

Signed-off-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Reviewed-by: Tiwei Bie <tiwei.bie@intel.com>
2019-06-13 23:54:29 +09:00
Maxime Coquelin
084fac96ca vhost: do not inline unlikely fragmented buffers code
Handling of fragmented virtio-net header and indirect descriptors
tables was implemented to fix CVE-2018-1059. It should never
happen with healthy guests and so is already considered as
unlikely code path.

This patch moves these bits into non-inline dedicated functions
to reduce the I-cache pressure.

Signed-off-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Reviewed-by: Tiwei Bie <tiwei.bie@intel.com>
2019-06-13 23:54:29 +09:00
Maxime Coquelin
5a5f6e78b2 vhost: do not inline packed and split functions
At runtime either packed Tx/Rx functions will always be called,
or split Tx/Rx functions will always be called.

This patch removes the forced inlining in order to reduce
the I-cache pressure.

Signed-off-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Reviewed-by: Tiwei Bie <tiwei.bie@intel.com>
2019-06-13 23:54:29 +09:00
David Marchand
0c9da7555d net: replace IPv4/v6 constants with uppercase name
Since we change these macros, we might as well avoid triggering complaints
from checkpatch because of mixed case.

old=RTE_IPv4
new=RTE_IPV4
git grep -lw $old | xargs sed -i -e "s/\<$old\>/$new/g"

old=RTE_ETHER_TYPE_IPv4
new=RTE_ETHER_TYPE_IPV4
git grep -lw $old | xargs sed -i -e "s/\<$old\>/$new/g"

old=RTE_ETHER_TYPE_IPv6
new=RTE_ETHER_TYPE_IPV6
git grep -lw $old | xargs sed -i -e "s/\<$old\>/$new/g"

Signed-off-by: David Marchand <david.marchand@redhat.com>
Reviewed-by: Olivier Matz <olivier.matz@6wind.com>
2019-06-03 16:54:54 +02:00
Olivier Matz
e73e3547ce net: add rte prefix to UDP structure
Add 'rte_' prefix to structures:
- rename struct udp_hdr as struct rte_udp_hdr.

Signed-off-by: Olivier Matz <olivier.matz@6wind.com>
Reviewed-by: Stephen Hemminger <stephen@networkplumber.org>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Reviewed-by: Ferruh Yigit <ferruh.yigit@intel.com>
2019-05-24 13:34:46 +02:00
Olivier Matz
f41b5156fe net: add rte prefix to TCP structure
Add 'rte_' prefix to structures:
- rename struct tcp_hdr as struct rte_tcp_hdr.

Signed-off-by: Olivier Matz <olivier.matz@6wind.com>
Reviewed-by: Stephen Hemminger <stephen@networkplumber.org>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Reviewed-by: Ferruh Yigit <ferruh.yigit@intel.com>
2019-05-24 13:34:46 +02:00
Olivier Matz
09d9ae1ac9 net: add rte prefix to SCTP structure
Add 'rte_' prefix to structures:
- rename struct sctp_hdr as struct rte_sctp_hdr.

Signed-off-by: Olivier Matz <olivier.matz@6wind.com>
Reviewed-by: Stephen Hemminger <stephen@networkplumber.org>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Reviewed-by: Ferruh Yigit <ferruh.yigit@intel.com>
2019-05-24 13:34:46 +02:00
Olivier Matz
a7c528e5d7 net: add rte prefix to IP structure
Add 'rte_' prefix to structures:
- rename struct ipv4_hdr as struct rte_ipv4_hdr.
- rename struct ipv6_hdr as struct rte_ipv6_hdr.

Signed-off-by: Olivier Matz <olivier.matz@6wind.com>
Reviewed-by: Stephen Hemminger <stephen@networkplumber.org>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Reviewed-by: Ferruh Yigit <ferruh.yigit@intel.com>
2019-05-24 13:34:46 +02:00
Olivier Matz
35b2d13fd6 net: add rte prefix to ether defines
Add 'RTE_' prefix to defines:
- rename ETHER_ADDR_LEN as RTE_ETHER_ADDR_LEN.
- rename ETHER_TYPE_LEN as RTE_ETHER_TYPE_LEN.
- rename ETHER_CRC_LEN as RTE_ETHER_CRC_LEN.
- rename ETHER_HDR_LEN as RTE_ETHER_HDR_LEN.
- rename ETHER_MIN_LEN as RTE_ETHER_MIN_LEN.
- rename ETHER_MAX_LEN as RTE_ETHER_MAX_LEN.
- rename ETHER_MTU as RTE_ETHER_MTU.
- rename ETHER_MAX_VLAN_FRAME_LEN as RTE_ETHER_MAX_VLAN_FRAME_LEN.
- rename ETHER_MAX_VLAN_ID as RTE_ETHER_MAX_VLAN_ID.
- rename ETHER_MAX_JUMBO_FRAME_LEN as RTE_ETHER_MAX_JUMBO_FRAME_LEN.
- rename ETHER_MIN_MTU as RTE_ETHER_MIN_MTU.
- rename ETHER_LOCAL_ADMIN_ADDR as RTE_ETHER_LOCAL_ADMIN_ADDR.
- rename ETHER_GROUP_ADDR as RTE_ETHER_GROUP_ADDR.
- rename ETHER_TYPE_IPv4 as RTE_ETHER_TYPE_IPv4.
- rename ETHER_TYPE_IPv6 as RTE_ETHER_TYPE_IPv6.
- rename ETHER_TYPE_ARP as RTE_ETHER_TYPE_ARP.
- rename ETHER_TYPE_VLAN as RTE_ETHER_TYPE_VLAN.
- rename ETHER_TYPE_RARP as RTE_ETHER_TYPE_RARP.
- rename ETHER_TYPE_QINQ as RTE_ETHER_TYPE_QINQ.
- rename ETHER_TYPE_ETAG as RTE_ETHER_TYPE_ETAG.
- rename ETHER_TYPE_1588 as RTE_ETHER_TYPE_1588.
- rename ETHER_TYPE_SLOW as RTE_ETHER_TYPE_SLOW.
- rename ETHER_TYPE_TEB as RTE_ETHER_TYPE_TEB.
- rename ETHER_TYPE_LLDP as RTE_ETHER_TYPE_LLDP.
- rename ETHER_TYPE_MPLS as RTE_ETHER_TYPE_MPLS.
- rename ETHER_TYPE_MPLSM as RTE_ETHER_TYPE_MPLSM.
- rename ETHER_VXLAN_HLEN as RTE_ETHER_VXLAN_HLEN.
- rename ETHER_ADDR_FMT_SIZE as RTE_ETHER_ADDR_FMT_SIZE.
- rename VXLAN_GPE_TYPE_IPV4 as RTE_VXLAN_GPE_TYPE_IPV4.
- rename VXLAN_GPE_TYPE_IPV6 as RTE_VXLAN_GPE_TYPE_IPV6.
- rename VXLAN_GPE_TYPE_ETH as RTE_VXLAN_GPE_TYPE_ETH.
- rename VXLAN_GPE_TYPE_NSH as RTE_VXLAN_GPE_TYPE_NSH.
- rename VXLAN_GPE_TYPE_MPLS as RTE_VXLAN_GPE_TYPE_MPLS.
- rename VXLAN_GPE_TYPE_GBP as RTE_VXLAN_GPE_TYPE_GBP.
- rename VXLAN_GPE_TYPE_VBNG as RTE_VXLAN_GPE_TYPE_VBNG.
- rename ETHER_VXLAN_GPE_HLEN as RTE_ETHER_VXLAN_GPE_HLEN.

Do not update the command line library to avoid adding a dependency to
librte_net.

Signed-off-by: Olivier Matz <olivier.matz@6wind.com>
Reviewed-by: Stephen Hemminger <stephen@networkplumber.org>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Reviewed-by: Ferruh Yigit <ferruh.yigit@intel.com>
2019-05-24 13:34:45 +02:00
Olivier Matz
6d13ea8e8e net: add rte prefix to ether structures
Add 'rte_' prefix to structures:
- rename struct ether_addr as struct rte_ether_addr.
- rename struct ether_hdr as struct rte_ether_hdr.
- rename struct vlan_hdr as struct rte_vlan_hdr.
- rename struct vxlan_hdr as struct rte_vxlan_hdr.
- rename struct vxlan_gpe_hdr as struct rte_vxlan_gpe_hdr.

Do not update the command line library to avoid adding a dependency to
librte_net.

Signed-off-by: Olivier Matz <olivier.matz@6wind.com>
Reviewed-by: Stephen Hemminger <stephen@networkplumber.org>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Reviewed-by: Ferruh Yigit <ferruh.yigit@intel.com>
2019-05-24 13:34:45 +02:00
Tiwei Bie
2a2904fa9c vhost: fix potential use-after-free for memory region
Reclaim outstanding zmbufs first before freeing memory regions,
otherwise there could be use-after-free.

Fixes: b0a985d1f340 ("vhost: add dequeue zero copy")
Cc: stable@dpdk.org

Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
2019-03-01 18:17:36 +01:00
Tiwei Bie
d767436ee5 vhost: fix potential use-after-free for zero copy mbuf
Don't free the zero copy mbufs before they have been consumed,
otherwise there could be use-after-free.

Fixes: b0a985d1f340 ("vhost: add dequeue zero copy")
Cc: stable@dpdk.org

Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
2019-03-01 18:17:36 +01:00
Tiwei Bie
041d37b2ef vhost: restore mbuf first when freeing zmbuf
The mbufs should also be restored in free_zmbufs().

Fixes: b0a985d1f340 ("vhost: add dequeue zero copy")
Fixes: 3ebd930588b7 ("vhost: fix mbuf free")
Cc: stable@dpdk.org

Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
2019-03-01 18:17:35 +01:00
Tiwei Bie
4800639000 vhost: fix access for indirect descriptors
Fix a possible out of bound access which may happen when handling
indirect descs in split ring.

Fixes: 1be4ebb1c464 ("vhost: support indirect descriptor in mergeable Rx")
Cc: stable@dpdk.org

Reported-by: Haiyue Wang <haiyue.wang@intel.com>
Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
2019-01-24 10:08:31 +01:00
Tiwei Bie
450539b47e vhost: fix possible dead loop in vector filling
Fix a possible dead loop which may happen, e.g. when driver
created a loop in the desc list and lens in descs are zero.

Fixes: fd68b4739d2c ("vhost: use buffer vectors in dequeue path")
Fixes: 2f3225a7d69b ("vhost: add vector filling support for packed ring")
Cc: stable@dpdk.org

Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
2019-01-14 17:44:29 +01:00
Tiwei Bie
06fc8545fd vhost: fix possible out of bound access in vector filling
Fixes: 7f74b95c444f ("vhost: pre update used ring for Tx and Rx")
Cc: stable@dpdk.org

Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
2019-01-14 17:44:29 +01:00
Maxime Coquelin
b473ec1131 vhost: batch used descs chains write-back with packed ring
Instead of writing back descriptors chains in order, let's
write the first chain flags last in order to improve batching.

Also, move the write barrier in logging cache sync, so that it
is done only when logging is enabled. It means there is now
one more barrier for split ring when logging is enabled.

With Kernel's pktgen benchmark, ~3% performance gain is measured.

Signed-off-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Tiwei Bie <tiwei.bie@intel.com>
2018-12-21 16:22:41 +01:00
Maxime Coquelin
815814c4ff vhost: remove useless prefetch for packed ring descriptor
This prefetch does not show any performance improvement.

Signed-off-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Tiwei Bie <tiwei.bie@intel.com>
2018-12-21 16:22:41 +01:00
Maxime Coquelin
aaf8979d6f vhost: prefetch descriptor after the read barrier
This patch moves the prefetch after the available index
is read to avoid prefetching a descriptor not available yet.

Signed-off-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Tiwei Bie <tiwei.bie@intel.com>
2018-12-21 16:22:41 +01:00
Maxime Coquelin
33e12d63d1 vhost: enforce desc flags and content read ordering
A read barrier is required to ensure that the ordering between
descriptor's flags and content reads is enforced.

1. read flags = desc->flags
if (flags & AVAIL_BIT)
2.   read desc->id

There is a control dependency between steps 1 and step 2.
2 could be speculatively executed before 1, which could result
in 'id' to not be updated yet.

Fixes: 2f3225a7d69b ("vhost: add vector filling support for packed ring")
Cc: stable@dpdk.org

Reported-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Acked-by: Ilya Maximets <i.maximets@samsung.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Tiwei Bie <tiwei.bie@intel.com>
2018-12-21 16:22:41 +01:00
Maxime Coquelin
d4ff2135eb vhost: enforce avail index and desc read ordering
A read barrier is required to ensure the ordering between
available index and the descriptor reads is enforced.

1. read avail_head = avail->idx
2. read cur_idx = last_avail_idx
if (cur_idx != avail_head) {
    3. read idx = avail->ring[cur_idx]
    4. read desc[idx]
}

There is a control dependency between step 1 and steps 3 & 4,
3 could be speculatively executed before 1, which could result
in 'idx' to not being updated yet.

Fixes: 4796ad63ba1f ("examples/vhost: import userspace vhost application")
Cc: stable@dpdk.org

Reported-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Acked-by: Ilya Maximets <i.maximets@samsung.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Tiwei Bie <tiwei.bie@intel.com>
2018-12-21 16:22:41 +01:00
Xiao Wang
b13ad2decc vhost: provide helpers for virtio ring relay
This patch provides two helpers for vdpa device driver to perform a
relay between the guest virtio ring and a mediated virtio ring.

The available ring relay will synchronize the available entries, and
help to do desc validity checking.

The used ring relay will synchronize the used entries from mediated ring
to guest ring, and help to do dirty page logging for live migration.

The later patch will leverage these two helpers.

Signed-off-by: Xiao Wang <xiao.w.wang@intel.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
2018-12-21 16:22:40 +01:00
Tiwei Bie
30affaeebc vhost: fix IOVA access for packed ring
We should apply for RO access when receiving packets from the
VM and apply for RW access when sending packets to the VM.

Fixes: a922401f35cc ("vhost: add Rx support for packed ring")
Fixes: ae999ce49dcb ("vhost: add Tx support for packed ring")
Cc: stable@dpdk.org

Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
2018-11-14 00:35:53 +01:00
Maxime Coquelin
e988a6d845 vhost: avoid memory barriers when no descriptors dequeued
In both split and packed dequeue paths, flush_shadow_used_ring
and vhost_ring_call variants gets called even if not packets
have been dequeued, and so no descriptors updates happened.

It has an impact on CPU pipeline, as memory barriers are used
in these functions.

This patch don't call these functions if no descriptors have
been dequeued. The performance gain with split ring when
dequeue zero-copy is disabled should be null, but should be
noticeable with packed ring or dequeue zero-copy enabled.

Fixes: ae999ce49dcb ("vhost: add Tx support for packed ring")
Fixes: 915cf9404225 ("vhost: use shadow used ring in dequeue path")
Cc: stable@dpdk.org

Signed-off-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Reviewed-by: Jens Freimann <jfreimann@redhat.com>
Tested-by: Jens Freimann <jfreimann@redhat.com>
Reviewed-by: Tiwei Bie <tiwei.bie@intel.com>
2018-10-26 22:14:06 +02:00
Tiwei Bie
16b9e38e74 vhost: fix vector filling for packed ring
We should return the length of the buffers described by
the current descriptor chain after filling the buffer
vector. So we need to zero the *len first.

Fixes: 2f3225a7d69b ("vhost: add vector filling support for packed ring")
Cc: stable@dpdk.org

Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
2018-10-26 22:14:05 +02:00
Jiayu Hu
729199397f vhost: fix corner case for enqueue operation
When performing enqueue operations on the split and packed rings,
if the reserved buffer length from the descriptor table exceeds
65535, the returned length by fill_vec_buf_split/_packed()
overflows. This patch is to avoid this corner case.

Fixes: f689586bc060 ("vhost: shadow used ring update")
Fixes: fd68b4739d2c ("vhost: use buffer vectors in dequeue path")
Fixes: 2f3225a7d69b ("vhost: add vector filling support for packed ring")
Fixes: 37f5e79a271d ("vhost: add shadow used ring support for packed rings")
Fixes: a922401f35cc ("vhost: add Rx support for packed ring")
Fixes: ae999ce49dcb ("vhost: add Tx support for packed ring")
Cc: stable@dpdk.org

Signed-off-by: Jiayu Hu <jiayu.hu@intel.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
2018-09-28 01:41:03 +02:00
Tiwei Bie
58e90a9113 vhost: fix return value on enqueue path
Fixes: 62250c1d0978 ("vhost: extract split ring handling from Rx and Tx functions")
Fixes: a922401f35cc ("vhost: add Rx support for packed ring")
Cc: stable@dpdk.org

Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
2018-09-14 20:08:41 +02:00
Tiwei Bie
adead74939 vhost: remove unused variable
The nr_updated is just increased and not really used.

Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
2018-08-02 04:41:49 +02:00
Tiwei Bie
0989161b26 vhost: release locks on RARP packet failure
Fixes: eefac9536a90 ("vhost: postpone device creation until rings are mapped")
Cc: stable@dpdk.org

Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
Reviewed-by: Jens Freimann <jfreimann@redhat.com>
2018-07-26 10:02:52 +02:00
Tiwei Bie
14962a9c4f vhost: fix overflow on shadow used ring
The shadow used ring's size is the same as the vq's size,
so we shouldn't try more than "vq size" times. Besides,
the element pointed by avail->idx isn't available to the
device, so we will return error when try "vq size" times.

Fixes: 24e4844048e1 ("vhost: unify Rx mergeable and non-mergeable paths")
Fixes: a922401f35cc ("vhost: add Rx support for packed ring")

Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
Reviewed-by: Jens Freimann <jfreimann@redhat.com>
2018-07-26 10:02:50 +02:00