The vdpa device can be reset many times in sequence without any
significant state changes in between. Previously this was not a problem:
VQs were torn down only on first reset. But after VQ pre-creation was
introduced, each reset will delete and re-create the hardware VQs and
their associated resources.
To solve this problem, avoid resetting hardware VQs if the VQs are still
in a blank state.
Reviewed-by: Cosmin Ratiu <cratiu@nvidia.com>
Acked-by: Eugenio Pérez <eperezma@redhat.com>
Signed-off-by: Dragos Tatulea <dtatulea@nvidia.com>
Message-Id: <20240626-stage-vdpa-vq-precreate-v2-23-560c491078df@nvidia.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
There are a few conditions under which the hardware VQs need a full
teardown and setup:
- VQ size changed to something else than default value. Hardware VQ size
modification is not supported.
- User turns off certain device features: mergeable buffers, checksum
virtio 1.0 compliance. In these cases, the TIR and RQT need to be
re-created.
Add a needs_teardown configuration variable and set it when detecting
the above scenarios. On next DRIVER_OK, the resources will be torn down
first.
Reviewed-by: Cosmin Ratiu <cratiu@nvidia.com>
Acked-by: Eugenio Pérez <eperezma@redhat.com>
Signed-off-by: Dragos Tatulea <dtatulea@nvidia.com>
Message-Id: <20240626-stage-vdpa-vq-precreate-v2-22-560c491078df@nvidia.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Currently, hardware VQs are created right when the vdpa device gets into
DRIVER_OK state. That is easier because most of the VQ state is known by
then.
This patch switches to creating all VQs and their associated resources
at device creation time. The motivation is to reduce the vdpa device
live migration downtime by moving the expensive operation of creating
all the hardware VQs and their associated resources out of downtime on
the destination VM.
The VQs are now created in a blank state. The VQ configuration will
happen later, on DRIVER_OK. Then the configuration will be applied when
the VQs are moved to the Ready state.
When .set_vq_ready() is called on a VQ before DRIVER_OK, special care is
needed: now that the VQ is already created a resume_vq() will be
triggered too early when no mr has been configured yet. Skip calling
resume_vq() in this case, let it be handled during DRIVER_OK.
For virtio-vdpa, the device configuration is done earlier during
.vdpa_dev_add() by vdpa_register_device(). Avoid calling
setup_vq_resources() a second time in that case.
On a 64 CPU, 256 GB VM with 1 vDPA device of 16 VQps, the full VQ
resource creation + resume time was ~370ms. Now it's down to 60 ms
(only VQ config and resume). The measurements were done on a ConnectX6DX
based vDPA device.
Signed-off-by: Dragos Tatulea <dtatulea@nvidia.com>
Reviewed-by: Cosmin Ratiu <cratiu@nvidia.com>
Message-Id: <20240626-stage-vdpa-vq-precreate-v2-21-560c491078df@nvidia.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Resume a VQ if it is already created when the number of VQ pairs
increases. This is done in preparation for VQ pre-creation which is
coming in a later patch. It is necessary because calling setup_vq() on
an already created VQ will return early and will not enable the queue.
For symmetry, suspend a VQ instead of tearing it down when the number of
VQ pairs decreases. But only if the resume operation is supported.
Reviewed-by: Cosmin Ratiu <cratiu@nvidia.com>
Acked-by: Eugenio Pérez <eperezma@redhat.com>
Signed-off-by: Dragos Tatulea <dtatulea@nvidia.com>
Message-Id: <20240626-stage-vdpa-vq-precreate-v2-20-560c491078df@nvidia.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
There are a few more places modifying the VQ to Ready directly. Let's
consolidate them into resume_vq().
The redundant warnings for resume_vq() errors can also be dropped.
There is one special case that needs to be handled for virtio-vdpa:
the initialized flag must be set to true earlier in setup_vq() so that
resume_vq() doesn't return early.
Reviewed-by: Cosmin Ratiu <cratiu@nvidia.com>
Acked-by: Eugenio Pérez <eperezma@redhat.com>
Signed-off-by: Dragos Tatulea <dtatulea@nvidia.com>
Message-Id: <20240626-stage-vdpa-vq-precreate-v2-18-560c491078df@nvidia.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Currently rqt_size is initialized during device flag configuration.
That's because it is the earliest moment when device knows if MQ
(multi queue) is on or off.
Shift this configuration earlier to device creation time. This implies
that non-MQ devices will have a larger RQT size. But the configuration
will still be correct.
This is done in preparation for the pre-creation of hardware virtqueues
at device add time. When that change will be added, RQT will be created
at device creation time so it needs to be initialized to its max size.
Reviewed-by: Cosmin Ratiu <cratiu@nvidia.com>
Acked-by: Eugenio Pérez <eperezma@redhat.com>
Signed-off-by: Dragos Tatulea <dtatulea@nvidia.com>
Message-Id: <20240626-stage-vdpa-vq-precreate-v2-13-560c491078df@nvidia.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
The virtqueue size is a pre-requisite for setting up any virtqueue
resources. For the upcoming optimization of creating virtqueues at
device add, the virtqueue size has to be configured.
The queue size check in setup_vq() will always be false. So remove it.
Signed-off-by: Dragos Tatulea <dtatulea@nvidia.com>
Reviewed-by: Cosmin Ratiu <cratiu@nvidia.com>
Message-Id: <20240626-stage-vdpa-vq-precreate-v2-12-560c491078df@nvidia.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
The hardware VQ configuration is mirrored by data in struct
mlx5_vdpa_virtqueue . Instead of clearing just a few fields at reset,
fully clear the struct and initialize with the appropriate default
values.
As clear_vqs_ready() is used only during reset, get rid of it.
Reviewed-by: Cosmin Ratiu <cratiu@nvidia.com>
Acked-by: Eugenio Pérez <eperezma@redhat.com>
Signed-off-by: Dragos Tatulea <dtatulea@nvidia.com>
Message-Id: <20240626-stage-vdpa-vq-precreate-v2-8-560c491078df@nvidia.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
The virtio spec says that a vdpa device should start off with one queue
pair. The driver is already compliant.
This patch moves the initialization to device add and reset times. This
is done in preparation for the pre-creation of hardware virtqueues at
device add time.
Signed-off-by: Dragos Tatulea <dtatulea@nvidia.com>
Reviewed-by: Cosmin Ratiu <cratiu@nvidia.com>
Message-Id: <20240626-stage-vdpa-vq-precreate-v2-7-560c491078df@nvidia.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Eugenio Pérez <eperezma@redhat.com>
The MLX driver was not updating its control virtqueue size at set_vq_num
and instead always initialized to MLX5_CVQ_MAX_ENT (16) at
setup_cvq_vring.
Qemu would try to set the size to 64 by default, however, because the
CVQ size always was initialized to 16, an error would be thrown when
sending >16 control messages (as used-ring entry 17 is initialized to 0).
For example, starting a guest with x-svq=on and then executing the
following command would produce the error below:
# for i in {1..20}; do ifconfig eth0 hw ether XX:xx:XX:xx:XX:XX; done
qemu-system-x86_64: Insufficient written data (0)
[ 435.331223] virtio_net virtio0: Failed to set mac address by vq command.
SIOCSIFHWADDR: Invalid argument
Acked-by: Dragos Tatulea <dtatulea@nvidia.com>
Acked-by: Eugenio Pérez <eperezma@redhat.com>
Signed-off-by: Jonah Palmer <jonah.palmer@oracle.com>
Message-Id: <20240216142502.78095-1-jonah.palmer@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Tested-by: Lei Yang <leiyang@redhat.com>
Fixes: 5262912ef3 ("vdpa/mlx5: Add support for control VQ and MAC setting")
Deleting the old mr during mr update (.set_map) and then modifying the
vqs with the new mr is not a good flow for firmware. The firmware
expects that mkeys are deleted after there are no more vqs referencing
them.
Introduce reference counting for mrs to fix this. It is the only way to
make sure that mkeys are not in use by vqs.
An mr reference is taken when the mr is associated to the mr asid table
and when the mr is linked to the vq on create/modify. The reference is
released when the mkey is unlinked from the vq (trough modify/destroy)
and from the mr asid table.
To make things consistent, get rid of mlx5_vdpa_destroy_mr and use
get/put semantics everywhere.
Reviewed-by: Gal Pressman <gal@nvidia.com>
Acked-by: Eugenio Pérez <eperezma@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Dragos Tatulea <dtatulea@nvidia.com>
Message-Id: <20231225151203.152687-8-dtatulea@nvidia.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Instead of tearing down and setting up vq resources, use vq
suspend/resume during .set_map to speed things up a bit.
The vq mr is updated with the new mapping while the vqs are suspended.
If the device doesn't support resumable vqs, do the old teardown and
setup dance.
Reviewed-by: Gal Pressman <gal@nvidia.com>
Acked-by: Eugenio Pérez <eperezma@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Dragos Tatulea <dtatulea@nvidia.com>
Message-Id: <20231225151203.152687-7-dtatulea@nvidia.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
.set_vq_state will set the indices and mark the fields to be modified in
the hw vq.
Advertise that the device supports changing the vq state when the device
is in DRIVER_OK state and suspended.
Reviewed-by: Gal Pressman <gal@nvidia.com>
Signed-off-by: Dragos Tatulea <dtatulea@nvidia.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20231225151203.152687-6-dtatulea@nvidia.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
mlx5_vdpa does not preserve userland's view of vring base for the control
queue in the following sequence:
ioctl VHOST_SET_VRING_BASE
ioctl VHOST_VDPA_SET_STATUS VIRTIO_CONFIG_S_DRIVER_OK
mlx5_vdpa_set_status()
setup_cvq_vring()
vringh_init_iotlb()
vringh_init_kern()
vrh->last_avail_idx = 0;
ioctl VHOST_GET_VRING_BASE
To fix, restore the value of cvq->vring.last_avail_idx after calling
vringh_init_iotlb.
Fixes: 5262912ef3 ("vdpa/mlx5: Add support for control VQ and MAC setting")
Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
Acked-by: Eugenio Pérez <eperezma@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Message-Id: <1699014387-194368-1-git-send-email-steven.sistare@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Since commit 6f5312f801 ("vdpa/mlx5: Add support for running with
virtio_vdpa"), mlx5_vdpa starts with preallocate 1:1 DMA MR at device
creation time. This 1:1 DMA MR will be implicitly destroyed while the
first .set_map call is invoked, in which case callers like vhost-vdpa
will start to set up custom mappings. When the .reset callback is
invoked, the custom mappings will be cleared and the 1:1 DMA MR will be
re-created.
In order to reduce excessive memory mapping cost in live migration, it
is desirable to decouple the vhost-vdpa IOTLB abstraction from the
virtio device life cycle, i.e. mappings can be kept around intact across
virtio device reset. Leverage the .reset_map callback, which is meant to
destroy the regular MR (including cvq mapping) on the given ASID and
recreate the initial DMA mapping. That way, the device .reset op runs
free from having to maintain and clean up memory mappings by itself.
Additionally, implement .compat_reset to cater for older userspace,
which may wish to see mapping to be cleared during reset.
Co-developed-by: Dragos Tatulea <dtatulea@nvidia.com>
Signed-off-by: Dragos Tatulea <dtatulea@nvidia.com>
Signed-off-by: Si-Wei Liu <si-wei.liu@oracle.com>
Message-Id: <1697880319-4937-7-git-send-email-si-wei.liu@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Tested-by: Lei Yang <leiyang@redhat.com>
Offer this backend feature as mlx5 is compatible with it. It allows it
to do live migration with CVQ, dynamically switching between passthrough
and shadow virtqueue.
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Message-Id: <20230703142514.363256-1-eperezma@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
For the following sequence:
- cvq group is in ASID 0
- .set_map(1, cvq_iotlb)
- .set_group_asid(cvq_group, 1)
... the cvq mapping from ASID 0 will be used. This is not always correct
behaviour.
This patch adds support for the above mentioned flow by saving the iotlb
on each .set_map and updating the cvq iotlb with it on a cvq group change.
Acked-by: Jason Wang <jasowang@redhat.com>
Acked-by: Eugenio Pérez <eperezma@redhat.com>
Signed-off-by: Dragos Tatulea <dtatulea@nvidia.com>
Message-Id: <20231018171456.1624030-18-dtatulea@nvidia.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Si-Wei Liu <si-wei.liu@oracle.com>
Tested-by: Si-Wei Liu <si-wei.liu@oracle.com>
Tested-by: Lei Yang <leiyang@redhat.com>
Vq descriptor mappings are supported in hardware by filling in an
additional mkey which contains the descriptor mappings to the hw vq.
A previous patch in this series added support for hw mkey (mr) creation
for ASID 1.
This patch fills in both the vq data and vq descriptor mkeys based on
group ASID mapping.
The feature is signaled to the vdpa core through the presence of the
.get_vq_desc_group op.
Acked-by: Jason Wang <jasowang@redhat.com>
Acked-by: Eugenio Pérez <eperezma@redhat.com>
Signed-off-by: Dragos Tatulea <dtatulea@nvidia.com>
Message-Id: <20231018171456.1624030-16-dtatulea@nvidia.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Si-Wei Liu <si-wei.liu@oracle.com>
Tested-by: Si-Wei Liu <si-wei.liu@oracle.com>
Tested-by: Lei Yang <leiyang@redhat.com>
The current flow for updating an mr works directly on mvdev->mr which
makes it cumbersome to handle multiple new mr structs.
This patch makes the flow more straightforward by having
mlx5_vdpa_create_mr return a new mr which will update the old mr (if
any). The old mr will be deleted and unlinked from mvdev. For the case
when the iotlb is empty (not NULL), the old mr will be cleared.
This change paves the way for adding mrs for different ASIDs.
The initialized bool is no longer needed as mr is now a pointer in the
mlx5_vdpa_dev struct which will be NULL when not initialized.
Acked-by: Eugenio Pérez <eperezma@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Dragos Tatulea <dtatulea@nvidia.com>
Message-Id: <20231018171456.1624030-14-dtatulea@nvidia.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Si-Wei Liu <si-wei.liu@oracle.com>
Tested-by: Si-Wei Liu <si-wei.liu@oracle.com>
Tested-by: Lei Yang <leiyang@redhat.com>
This patch adapts the mr creation/deletion code to be able to work with
any given mr struct pointer. All the APIs are adapted to take an extra
parameter for the mr.
mlx5_vdpa_create/delete_mr doesn't need a ASID parameter anymore. The
check is done in the caller instead (mlx5_set_map).
This change is needed for a followup patch which will introduce an
additional mr for the vq descriptor data.
Signed-off-by: Dragos Tatulea <dtatulea@nvidia.com>
Acked-by: Eugenio Pérez <eperezma@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20231018171456.1624030-12-dtatulea@nvidia.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Si-Wei Liu <si-wei.liu@oracle.com>
Tested-by: Si-Wei Liu <si-wei.liu@oracle.com>
Tested-by: Lei Yang <leiyang@redhat.com>
The handling of the cvq iotlb is currently coupled with the creation
and destruction of the hardware mkeys (mr).
This patch moves cvq iotlb handling into its own function and shifts it
to a scope that is not related to mr handling. As cvq handling is just a
prune_iotlb + dup_iotlb cycle, put it all in the same "update" function.
Finally, the destruction path is handled by directly pruning the iotlb.
After this move is done the ASID mr code can be collapsed into a single
function.
Acked-by: Jason Wang <jasowang@redhat.com>
Acked-by: Eugenio Pérez <eperezma@redhat.com>
Signed-off-by: Dragos Tatulea <dtatulea@nvidia.com>
Message-Id: <20231018171456.1624030-8-dtatulea@nvidia.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Si-Wei Liu <si-wei.liu@oracle.com>
Tested-by: Si-Wei Liu <si-wei.liu@oracle.com>
Tested-by: Lei Yang <leiyang@redhat.com>
A firmware error is triggered when configuring a 9k MTU on the PF after
switching to switchdev mode and then using a vdpa device with larger
(1k) rings:
mlx5_cmd_out_err: CREATE_GENERAL_OBJECT(0xa00) op_mod(0xd) failed, status bad resource(0x5), syndrome (0xf6db90), err(-22)
This is due to the fact that the hw VQ size parameters are computed
based on the umem_1/2/3_buffer_param_a/b capabilities and all
device capabilities are read only when the driver is moved to switchdev mode.
The problematic configuration flow looks like this:
1) Create VF
2) Unbind VF
3) Switch PF to switchdev mode.
4) Bind VF
5) Set PF MTU to 9k
6) create vDPA device
7) Start VM with vDPA device and 1K queue size
Note that setting the MTU before step 3) doesn't trigger this issue.
This patch reads the forementioned umem parameters at the latest point
possible before the VQs of the device are created.
v2:
- Allocate output with kmalloc to reduce stack frame size.
- Removed stable from cc.
Fixes: 1a86b377aa ("vdpa/mlx5: Add VDPA driver for supported mlx5 devices")
Signed-off-by: Dragos Tatulea <dtatulea@nvidia.com>
Message-Id: <20230831155702.1080754-1-dtatulea@nvidia.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
The error path in setup_driver deletes the debugfs entry but doesn't
clear the pointer. During .dev_del the invalid pointer will be released
again causing a crash.
This patch fixes the issue by always clearing the debugfs entry in
mlx5_vdpa_remove_debugfs. Also, stop removing the debugfs entry in
.dev_del op: the debugfs entry is already handled within the
setup_driver/teardown_driver scope.
Cc: stable@vger.kernel.org
Fixes: f0417e72ad ("vdpa/mlx5: Add and remove debugfs in setup/teardown driver")
Signed-off-by: Dragos Tatulea <dtatulea@nvidia.com>
Reviewed-by: Gal Pressman <gal@nvidia.com>
Message-Id: <20230829174014.928189-2-dtatulea@nvidia.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Pull virtio updates from Michael Tsirkin:
"A small pull request this time around, mostly because the vduse
network got postponed to next relase so we can be sure we got the
security store right"
* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
virtio_ring: fix avail_wrap_counter in virtqueue_add_packed
virtio_vdpa: build affinity masks conditionally
virtio_net: merge dma operations when filling mergeable buffers
virtio_ring: introduce dma sync api for virtqueue
virtio_ring: introduce dma map api for virtqueue
virtio_ring: introduce virtqueue_reset()
virtio_ring: separate the logic of reset/enable from virtqueue_resize
virtio_ring: correct the expression of the description of virtqueue_resize()
virtio_ring: skip unmap for premapped
virtio_ring: introduce virtqueue_dma_dev()
virtio_ring: support add premapped buf
virtio_ring: introduce virtqueue_set_dma_premapped()
virtio_ring: put mapping error check in vring_map_one_sg
virtio_ring: check use_dma_api before unmap desc for indirect
vdpa_sim: offer VHOST_BACKEND_F_ENABLE_AFTER_DRIVER_OK
vdpa: add get_backend_features vdpa operation
vdpa: accept VHOST_BACKEND_F_ENABLE_AFTER_DRIVER_OK backend feature
vdpa: add VHOST_BACKEND_F_ENABLE_AFTER_DRIVER_OK flag
vdpa/mlx5: Remove unused function declarations
