Some vhost-user driver may need this info to setup its own page tables
for GPA (guest physical addr) to HPA (host physical addr) translation.
SPDK (Storage Performance Development Kit) is one example.
Besides, by exporting this memory info, we could also export the
gpa_to_vva() as an inline function, which helps for performance.
Otherwise, it has to be referenced indirectly by a "vid".
Signed-off-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Assume there is an application both support vhost-user net and
vhost-user scsi, the callback should be different. Making notify
ops per vhost driver allow application define different set of
callbacks for different driver.
Signed-off-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
This patch adds a new status flag indicating the Virtio device
is ready to operate.
This is required to be able to call rte_vhost_mtu_get() in the
.new_device() callback, as rte_vhost_mtu_get needs that the
negotiation is done, but it is too early to rely on running status
flag, which is set just after .new_device() returns.
Signed-off-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Acked-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
This patch implements the vhost-user MTU protocol feature support.
When VIRTIO_NET_F_MTU is negotiated, QEMU notifies the vhost-user
backend with the configured MTU if dedicated protocol feature is
supported.
The value can be used by the application to ensure consistency with
value set by the user.
Signed-off-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Acked-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
This patch enables the new VIRTIO_NET_F_MTU feature,
which makes possible for the host to advise the guest
with its maximum supported MTU.
MTU value is set via QEMU parameters, either via Libvirt XML, or
directly in virtio-net device command line arguments.
Signed-off-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Acked-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
0x8000 is the max virito-net queue pairs the virtio 1.0 spec claims to
support. While for vhost-user, it's a different story: the max vring
index could be passed by the vhost-user spec is 0xff, masked by the
VHOST_USER_VRING_IDX_MASK.
That said, the max queue pairs could vhost-user could supported is 0x80.
If user are asking more, I think the vhost-user need be extended.
Fixes: b09b198bfb ("vhost-user: announce queue number in message")
Cc: stable@dpdk.org
Signed-off-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
Some macros (say VIRTIO_NET_F_MQ) are needed for enabling multiple queue,
however they are introduced since kernel v3.8, meaning build error happens
if we build DPDK vhost on those platforms.
71dfdbe66a ("vhost: fix build with kernel < 3.8") meant to fix it, but
in a wrong way: it completely disables the MQ features for those kernels.
However, the MQ feature doesn't depend on the kernel at all (except the
macros dependency stated above), that we could still enable the MQ feature
even the host kernel has no such support.
The right fix is to define the macro if it's not defined.
Fixes: 71dfdbe66a ("vhost: fix build with kernel < 3.8")
Cc: stable@dpdk.org
Signed-off-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
vhost-cuse is removed, update corresponding comments that are still
referencing it.
Signed-off-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
Acked-by: John McNamara <john.mcnamara@intel.com>
The basic idea is to shadow the used ring update: update them into a
local buffer first, and then flush them all to the virtio used vring
at once in the end.
And since we do avail ring reservation before enqueuing data, we would
know which and how many descs will be used. Which means we could update
the shadow used ring at the reservation time. It also introduce another
slight advantage: we don't need access the desc->flag any more inside
copy_mbuf_to_desc_mergeable().
Signed-off-by: Zhihong Wang <zhihong.wang@intel.com>
Signed-off-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
Reviewed-by: Jianbo Liu <jianbo.liu@linaro.org>
Tested-by: Maxime Coquelin <maxime.coquelin@redhat.com>
last_used_idx is a local var, there is no need to decorate it
by "volatile".
Signed-off-by: Zhihong Wang <zhihong.wang@intel.com>
Reviewed-by: Jianbo Liu <jianbo.liu@linaro.org>
Tested-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Dequeue zero copy is disabled by default. Here add a new flag
``RTE_VHOST_USER_DEQUEUE_ZERO_COPY`` to explictily enable it.
Signed-off-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Tested-by: Qian Xu <qian.q.xu@intel.com>
The basic idea of dequeue zero copy is, instead of copying data from
the desc buf, here we let the mbuf reference the desc buf addr directly.
Doing so, however, has one major issue: we can't update the used ring
at the end of rte_vhost_dequeue_burst. Because we don't do the copy
here, an update of the used ring would let the driver to reclaim the
desc buf. As a result, DPDK might reference a stale memory region.
To update the used ring properly, this patch does several tricks:
- when mbuf references a desc buf, refcnt is added by 1.
This is to pin lock the mbuf, so that a mbuf free from the DPDK
won't actually free it, instead, refcnt is subtracted by 1.
- We chain all those mbuf together (by tailq)
And we check it every time on the rte_vhost_dequeue_burst entrance,
to see if the mbuf is freed (when refcnt equals to 1). If that
happens, it means we are the last user of this mbuf and we are
safe to update the used ring.
- "struct zcopy_mbuf" is introduced, to associate an mbuf with the
right desc idx.
Dequeue zero copy is introduced for performance reason, and some rough
tests show about 50% perfomance boost for packet size 1500B. For small
packets, (e.g. 64B), it actually slows a bit down (well, it could up to
15%). That is expected because this patch introduces some extra works,
and it outweighs the benefit from saving few bytes copy.
Signed-off-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Tested-by: Qian Xu <qian.q.xu@intel.com>
So far, we retrieve both the used ring and avail ring idx by the var
last_used_idx; it won't be a problem because the used ring is updated
immediately after those avail entries are consumed.
But that's not true when dequeue zero copy is enabled, that used ring is
updated only when the mbuf is consumed. Thus, we need use another var to
note the last avail ring idx we have consumed.
Therefore, last_avail_idx is introduced.
Signed-off-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Tested-by: Qian Xu <qian.q.xu@intel.com>
So that we can convert a guest physical address to host physical
address, which will be used in later Tx zero copy implementation.
MAP_POPULATE is set while mmaping guest memory regions, to make
sure the page tables are setup and then rte_mem_virt2phy() could
yield proper physical address.
Signed-off-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Tested-by: Qian Xu <qian.q.xu@intel.com>
Due to history reason (that vhost-cuse comes before vhost-user), some
fields for maintaining the vhost-user memory mappings (such as mmapped
address and size, with those we then can unmap on destroy) are kept in
"orig_region_map" struct, a structure that is defined only in vhost-user
source file.
The right way to go is to remove the structure and move all those fields
into virtio_memory_region struct. But we simply can't do that before,
because it breaks the ABI.
Now, thanks to the ABI refactoring, it's never been a blocking issue
any more. And here it goes: this patch removes orig_region_map and
redefines virtio_memory_region, to include all necessary info.
With that, we can simplify the guest/host address convert a bit.
Signed-off-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Tested-by: Qian Xu <qian.q.xu@intel.com>
The code structure is a bit messy now. For example, vhost-user message
handling is spread to three different files:
vhost-net-user.c virtio-net.c virtio-net-user.c
Where, vhost-net-user.c is the entrance to handle all those messages
and then invoke the right method for a specific message. Some of them
are stored at virtio-net.c, while others are stored at virtio-net-user.c.
The truth is all of them should be in one file, vhost_user.c.
So this patch refactors the source code structure: mainly on renaming
files and moving code from one file to another file that is more suitable
for storing it. Thus, no functional changes are made.
After the refactor, the code structure becomes to:
- socket.c handles all vhost-user socket file related stuff, such
as, socket file creation for server mode, reconnection
for client mode.
- vhost.c mainly on stuff like vhost device creation/destroy/reset.
Most of the vhost API implementation are there, too.
- vhost_user.c all stuff about vhost-user messages handling goes there.
- virtio_net.c all stuff about virtio-net should go there. It has virtio
net Rx/Tx implementation only so far: it's just a rename
from vhost_rxtx.c
Signed-off-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
