16 Commits

Author SHA1 Message Date
Stefano Garzarella
112f23cd72 vdpa_sim: move buffer allocation in the devices
Currently, the vdpa_sim core does not use the buffer, but only
allocates it.

The buffer is used by devices differently, and some future devices
may not use it. So let's move all its management inside the devices.

Add a new `free` device callback called to clean up the resources
allocated by the device.

Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Message-Id: <20230407133658.66339-2-sgarzare@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2023-04-21 03:02:35 -04:00
Stefano Garzarella
4bb94d2de2 vdpa_sim: add support for user VA
The new "use_va" module parameter (default: true) is used in
vdpa_alloc_device() to inform the vDPA framework that the device
supports VA.

vringh is initialized to use VA only when "use_va" is true and the
user's mm has been bound. So, only when the bus supports user VA
(e.g. vhost-vdpa).

vdpasim_mm_work_fn work is used to serialize the binding to a new
address space when the .bind_mm callback is invoked, and unbinding
when the .unbind_mm callback is invoked.

Call mmget_not_zero()/kthread_use_mm() inside the worker function
to pin the address space only as long as needed, following the
documentation of mmget() in include/linux/sched/mm.h:

  * Never use this function to pin this address space for an
  * unbounded/indefinite amount of time.

Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Message-Id: <20230404131734.45943-1-sgarzare@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2023-04-21 03:02:34 -04:00
Stefano Garzarella
d7621c28fc vdpa_sim: replace the spinlock with a mutex to protect the state
The spinlock we use to protect the state of the simulator is sometimes
held for a long time (for example, when devices handle requests).

This also prevents us from calling functions that might sleep (such as
kthread_flush_work() in the next patch), and thus having to release
and retake the lock.

For these reasons, let's replace the spinlock with a mutex that gives
us more flexibility.

Suggested-by: Jason Wang <jasowang@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Message-Id: <20230404131730.45920-1-sgarzare@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2023-04-21 03:02:33 -04:00
Stefano Garzarella
76acfa7bc5 vdpa_sim: use kthread worker
Let's use our own kthread to run device jobs.
This allows us more flexibility, especially we can attach the kthread
to the user address space when vDPA uses user's VA.

Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Message-Id: <20230404131725.45908-1-sgarzare@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2023-04-21 03:02:33 -04:00
Stefano Garzarella
e2a4f808a7 vdpa_sim: make devices agnostic for work management
Let's move work management inside the vdpa_sim core.
This way we can easily change how we manage the works, without
having to change the devices each time.

Acked-by: Eugenio Pérez Martin <eperezma@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Message-Id: <20230404131721.45886-1-sgarzare@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2023-04-21 03:02:33 -04:00
Jason Wang
6c3d329e64 vdpa_sim: get rid of DMA ops
We used to (ab)use the DMA ops for setting up identical mappings in
the IOTLB. This patch tries to get rid of the those unnecessary DMA
ops by maintaining a simple identical/passthrough mappings by
default. When bound to virtio_vdpa driver, DMA API will simply use PA
as the IOVA and we will be all fine. When the vDPA bus tries to setup
customized mapping (e.g when bound to vhost-vDPA), the
identical/passthrough mapping will be removed.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20221223060021.28011-1-jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Christoph Hellwig <hch@lst.de>
2023-02-20 19:26:58 -05:00
Jason Wang
5dbb063a3e vdpa_sim: support vendor statistics
This patch adds a new config ops callback to allow individual
simulator to implement the vendor stats callback.

Acked-by: Eugenio Pérez <eperezma@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20221223055548.27810-4-jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
2023-02-20 19:26:57 -05:00
Jason Wang
bb105d514a vdpasim: customize allocation size
Allow individual simulator to customize the allocation size.

Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Acked-by: Eugenio Pérez <eperezma@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20221223055548.27810-3-jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2023-02-20 19:26:57 -05:00
Sebastien Boeuf
f9d9f57ef0 vdpa_sim: Implement resume vdpa op
Implement resume operation for vdpa_sim devices, so vhost-vdpa will
offer that backend feature and userspace can effectively resume the
device.

Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Message-Id: <15a4566826033c5dd9a2167e5cfb0ef4d90cea49.1672742878.git.sebastien.boeuf@intel.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
2023-02-20 19:26:56 -05:00
Jason Wang
477f719714 vdpa_sim_net: support feature provisioning
This patch implements features provisioning for vdpa_sim_net.

1) validating the provisioned features to be a subset of the parent
   features.
2) clearing the features that is not wanted by the userspace

For example:

vdpasim_net:
  supported_classes net
  max_supported_vqs 3
  dev_features MTU MAC CTRL_VQ CTRL_MAC_ADDR ANY_LAYOUT VERSION_1 ACCESS_PLATFORM

1) provision vDPA device with all features that are supported by the
   net simulator

dev1: mac 00:00:00:00:00:00 link up link_announce false mtu 1500
  negotiated_features MTU MAC CTRL_VQ CTRL_MAC_ADDR VERSION_1 ACCESS_PLATFORM

2) provision vDPA device with a subset of the features

dev1: mac 00:00:00:00:00:00 link up link_announce false mtu 1500
  negotiated_features CTRL_VQ VERSION_1 ACCESS_PLATFORM

Reviewed-by: Eli Cohen <elic@nvidia.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20220927074810.28627-3-jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
2022-10-07 09:32:40 -04:00
Eugenio Pérez
0c89e2a3a9 vdpa_sim: Implement suspend vdpa op
Implement suspend operation for vdpa_sim devices, so vhost-vdpa will
offer that backend feature and userspace can effectively suspend the
device.

This is a must before get virtqueue indexes (base) for live migration,
since the device could modify them after userland gets them. There are
individual ways to perform that action for some devices
(VHOST_NET_SET_BACKEND, VHOST_VSOCK_SET_RUNNING, ...) but there was no
way to perform it for any vhost device (and, in particular, vhost-vdpa).

Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Message-Id: <20220810171512.2343333-5-eperezma@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-08-11 04:31:15 -04:00
Gautam Dawar
bda324fd03 vdpasim: control virtqueue support
This patch introduces the control virtqueue support for vDPA
simulator. This is a requirement for supporting advanced features like
multiqueue.

A requirement for control virtqueue is to isolate its memory access
from the rx/tx virtqueues. This is because when using vDPA device
for VM, the control virqueue is not directly assigned to VM. Userspace
(Qemu) will present a shadow control virtqueue to control for
recording the device states.

The isolation is done via the virtqueue groups and ASID support in
vDPA through vhost-vdpa. The simulator is extended to have:

1) three virtqueues: RXVQ, TXVQ and CVQ (control virtqueue)
2) two virtqueue groups: group 0 contains RXVQ and TXVQ; group 1
   contains CVQ
3) two address spaces and the simulator simply implements the address
   spaces by mapping it 1:1 to IOTLB.

For the VM use cases, userspace(Qemu) may set AS 0 to group 0 and AS 1
to group 1. So we have:

1) The IOTLB for virtqueue group 0 contains the mappings of guest, so
   RX and TX can be assigned to guest directly.
2) The IOTLB for virtqueue group 1 contains the mappings of CVQ which
   is the buffers that allocated and managed by VMM only. So CVQ of
   vhost-vdpa is visible to VMM only. And Guest can not access the CVQ
   of vhost-vdpa.

For the other use cases, since AS 0 is associated to all virtqueue
groups by default. All virtqueues share the same mapping by default.

To demonstrate the function, VIRITO_NET_F_CTRL_MACADDR is
implemented in the simulator for the driver to set mac address.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Gautam Dawar <gdawar@xilinx.com>
Message-Id: <20220330180436.24644-20-gdawar@xilinx.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-05-31 12:45:08 -04:00
Gautam Dawar
d4821902e4 vdpa: introduce virtqueue groups
This patch introduces virtqueue groups to vDPA device. The virtqueue
group is the minimal set of virtqueues that must share an address
space. And the address space identifier could only be attached to
a specific virtqueue group.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Gautam Dawar <gdawar@xilinx.com>
Message-Id: <20220330180436.24644-6-gdawar@xilinx.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-05-31 12:44:27 -04:00
Stefano Garzarella
4080fc1067 vdpa_sim: use iova module to allocate IOVA addresses
The identical mapping used until now created issues when mapping
different virtual pages with the same physical address.
To solve this issue, we can use the iova module, to handle the IOVA
allocation.
For simplicity we use an IOVA allocator with byte granularity.

We add two new functions, vdpasim_map_range() and vdpasim_unmap_range(),
to handle the IOVA allocation and the registration into the IOMMU/IOTLB.
These functions are used by dma_map_ops callbacks.

Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Link: https://lore.kernel.org/r/20210315163450.254396-2-sgarzare@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2021-05-03 04:55:52 -04:00
Parav Pandit
a3c06ae158 vdpa_sim_net: Add support for user supported devices
Enable user to create vdpasim net simulate devices.

Show vdpa management device that supports creating, deleting vdpa devices.

$ vdpa mgmtdev show
vdpasim_net:
  supported_classes
    net

$ vdpa mgmtdev show -jp
{
    "show": {
        "vdpasim_net": {
            "supported_classes": {
              "net"
        }
    }
}

Create a vdpa device of type networking named as "foo2" from
the management device vdpasim:

$ vdpa dev add mgmtdev vdpasim_net name foo2

Show the newly created vdpa device by its name:
$ vdpa dev show foo2
foo2: type network mgmtdev vdpasim_net vendor_id 0 max_vqs 2 max_vq_size 256

$ vdpa dev show foo2 -jp
{
    "dev": {
        "foo2": {
            "type": "network",
            "mgmtdev": "vdpasim_net",
            "vendor_id": 0,
            "max_vqs": 2,
            "max_vq_size": 256
        }
    }
}

Delete the vdpa device after its use:
$ vdpa dev del foo2

Signed-off-by: Parav Pandit <parav@nvidia.com>
Reviewed-by: Eli Cohen <elic@nvidia.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20210105103203.82508-7-parav@nvidia.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2021-02-23 07:52:56 -05:00
Max Gurtovoy
db1e8bb6c6 vdpa: split vdpasim to core and net modules
Introduce new vdpa_sim_net and vdpa_sim (core) drivers. This is a
preparation for adding a vdpa simulator module for block devices.

Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com>
[sgarzare: various cleanups/fixes]
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Link: https://lore.kernel.org/r/20201215144256.155342-19-sgarzare@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-12-18 16:14:30 -05:00