Re: [RFC PATCH v2 06/19] vdpa: multiple address spaces support

From: Eugenio Perez Martin
Date: Thu Mar 03 2022 - 14:44:05 EST

Next message: Hao Luo: "Re: [PATCH bpf-next v1 4/9] bpf: Introduce sleepable tracepoints"
Previous message: Mike Rapoport: "Re: [PATCH 00/35] Shadow stacks for userspace"
Next in thread: Gautam Dawar: "RE: [RFC PATCH v2 06/19] vdpa: multiple address spaces support"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]

On Thu, Feb 24, 2022 at 10:25 PM Gautam Dawar <gautam.dawar@xxxxxxxxxx> wrote:
>
> This patches introduces the multiple address spaces support for vDPA
> device. This idea is to identify a specific address space via an
> dedicated identifier - ASID.
>
> During vDPA device allocation, vDPA device driver needs to report the
> number of address spaces supported by the device then the DMA mapping
> ops of the vDPA device needs to be extended to support ASID.
>
> This helps to isolate the environments for the virtqueue that will not
> be assigned directly. E.g in the case of virtio-net, the control
> virtqueue will not be assigned directly to guest.
>
> As a start, simply claim 1 virtqueue groups and 1 address spaces for
> all vDPA devices. And vhost-vDPA will simply reject the device with
> more than 1 virtqueue groups or address spaces.
>
> Signed-off-by: Jason Wang <jasowang@xxxxxxxxxx>
> Signed-off-by: Gautam Dawar <gdawar@xxxxxxxxxx>
> ---
> drivers/vdpa/ifcvf/ifcvf_main.c | 2 +-
> drivers/vdpa/mlx5/net/mlx5_vnet.c | 5 +++--
> drivers/vdpa/vdpa.c | 4 +++-
> drivers/vdpa/vdpa_sim/vdpa_sim.c | 10 ++++++----
> drivers/vhost/vdpa.c | 14 +++++++++-----
> include/linux/vdpa.h | 28 +++++++++++++++++++---------
> 6 files changed, 41 insertions(+), 22 deletions(-)
>
> diff --git a/drivers/vdpa/ifcvf/ifcvf_main.c b/drivers/vdpa/ifcvf/ifcvf_main.c
> index c815a2e62440..a4815c5612f9 100644
> --- a/drivers/vdpa/ifcvf/ifcvf_main.c
> +++ b/drivers/vdpa/ifcvf/ifcvf_main.c
> @@ -513,7 +513,7 @@ static int ifcvf_vdpa_dev_add(struct vdpa_mgmt_dev *mdev, const char *name,
> pdev = ifcvf_mgmt_dev->pdev;
> dev = &pdev->dev;
> adapter = vdpa_alloc_device(struct ifcvf_adapter, vdpa,
> - dev, &ifc_vdpa_ops, 1, name, false);
> + dev, &ifc_vdpa_ops, 1, 1, name, false);
> if (IS_ERR(adapter)) {
> IFCVF_ERR(pdev, "Failed to allocate vDPA structure");
> return PTR_ERR(adapter);
> diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c b/drivers/vdpa/mlx5/net/mlx5_vnet.c
> index fcfc28460b72..a76417892ef3 100644
> --- a/drivers/vdpa/mlx5/net/mlx5_vnet.c
> +++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c
> @@ -2282,7 +2282,8 @@ static u32 mlx5_vdpa_get_generation(struct vdpa_device *vdev)
> return mvdev->generation;
> }
>
> -static int mlx5_vdpa_set_map(struct vdpa_device *vdev, struct vhost_iotlb *iotlb)
> +static int mlx5_vdpa_set_map(struct vdpa_device *vdev, unsigned int asid,
> + struct vhost_iotlb *iotlb)
> {
> struct mlx5_vdpa_dev *mvdev = to_mvdev(vdev);
> bool change_map;
> @@ -2581,7 +2582,7 @@ static int mlx5_vdpa_dev_add(struct vdpa_mgmt_dev *v_mdev, const char *name,
> }
>
> ndev = vdpa_alloc_device(struct mlx5_vdpa_net, mvdev.vdev, mdev->device, &mlx5_vdpa_ops,
> - 1, name, false);
> + 1, 1, name, false);
> if (IS_ERR(ndev))
> return PTR_ERR(ndev);
>
> diff --git a/drivers/vdpa/vdpa.c b/drivers/vdpa/vdpa.c
> index a07bf0130559..1793dc12b208 100644
> --- a/drivers/vdpa/vdpa.c
> +++ b/drivers/vdpa/vdpa.c
> @@ -160,6 +160,7 @@ static void vdpa_release_dev(struct device *d)
> * @parent: the parent device
> * @config: the bus operations that is supported by this device
> * @ngroups: number of groups supported by this device
> + * @nas: number of address spaces supported by this device
> * @size: size of the parent structure that contains private data
> * @name: name of the vdpa device; optional.
> * @use_va: indicate whether virtual address must be used by this device
> @@ -172,7 +173,7 @@ static void vdpa_release_dev(struct device *d)
> */
> struct vdpa_device *__vdpa_alloc_device(struct device *parent,
> const struct vdpa_config_ops *config,
> - unsigned int ngroups,
> + unsigned int ngroups, unsigned int nas,
> size_t size, const char *name,
> bool use_va)
> {
> @@ -206,6 +207,7 @@ struct vdpa_device *__vdpa_alloc_device(struct device *parent,
> vdev->features_valid = false;
> vdev->use_va = use_va;
> vdev->ngroups = ngroups;
> + vdev->nas = nas;
>
> if (name)
> err = dev_set_name(&vdev->dev, "%s", name);
> diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim.c b/drivers/vdpa/vdpa_sim/vdpa_sim.c
> index c98cb1f869fa..659e2e2e4b0c 100644
> --- a/drivers/vdpa/vdpa_sim/vdpa_sim.c
> +++ b/drivers/vdpa/vdpa_sim/vdpa_sim.c
> @@ -251,7 +251,7 @@ struct vdpasim *vdpasim_create(struct vdpasim_dev_attr *dev_attr)
> ops = &vdpasim_config_ops;
>
> vdpasim = vdpa_alloc_device(struct vdpasim, vdpa, NULL, ops, 1,
> - dev_attr->name, false);
> + 1, dev_attr->name, false);
> if (IS_ERR(vdpasim)) {
> ret = PTR_ERR(vdpasim);
> goto err_alloc;
> @@ -539,7 +539,7 @@ static struct vdpa_iova_range vdpasim_get_iova_range(struct vdpa_device *vdpa)
> return range;
> }
>
> -static int vdpasim_set_map(struct vdpa_device *vdpa,
> +static int vdpasim_set_map(struct vdpa_device *vdpa, unsigned int asid,
> struct vhost_iotlb *iotlb)
> {
> struct vdpasim *vdpasim = vdpa_to_sim(vdpa);
> @@ -566,7 +566,8 @@ static int vdpasim_set_map(struct vdpa_device *vdpa,
> return ret;
> }
>
> -static int vdpasim_dma_map(struct vdpa_device *vdpa, u64 iova, u64 size,
> +static int vdpasim_dma_map(struct vdpa_device *vdpa, unsigned int asid,
> + u64 iova, u64 size,
> u64 pa, u32 perm, void *opaque)
> {
> struct vdpasim *vdpasim = vdpa_to_sim(vdpa);
> @@ -580,7 +581,8 @@ static int vdpasim_dma_map(struct vdpa_device *vdpa, u64 iova, u64 size,
> return ret;
> }
>
> -static int vdpasim_dma_unmap(struct vdpa_device *vdpa, u64 iova, u64 size)
> +static int vdpasim_dma_unmap(struct vdpa_device *vdpa, unsigned int asid,
> + u64 iova, u64 size)
> {
> struct vdpasim *vdpasim = vdpa_to_sim(vdpa);
>
> diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c
> index 655ff7029401..6bf755f84d26 100644
> --- a/drivers/vhost/vdpa.c
> +++ b/drivers/vhost/vdpa.c
> @@ -599,10 +599,10 @@ static int vhost_vdpa_map(struct vhost_vdpa *v, struct vhost_iotlb *iotlb,
> return r;
>
> if (ops->dma_map) {
> - r = ops->dma_map(vdpa, iova, size, pa, perm, opaque);
> + r = ops->dma_map(vdpa, 0, iova, size, pa, perm, opaque);
> } else if (ops->set_map) {
> if (!v->in_batch)
> - r = ops->set_map(vdpa, iotlb);
> + r = ops->set_map(vdpa, 0, iotlb);
> } else {
> r = iommu_map(v->domain, iova, pa, size,
> perm_to_iommu_flags(perm));
> @@ -628,10 +628,10 @@ static void vhost_vdpa_unmap(struct vhost_vdpa *v,
> vhost_vdpa_iotlb_unmap(v, iotlb, iova, iova + size - 1);
>
> if (ops->dma_map) {
> - ops->dma_unmap(vdpa, iova, size);
> + ops->dma_unmap(vdpa, 0, iova, size);
> } else if (ops->set_map) {
> if (!v->in_batch)
> - ops->set_map(vdpa, iotlb);
> + ops->set_map(vdpa, 0, iotlb);
> } else {
> iommu_unmap(v->domain, iova, size);
> }
> @@ -863,7 +863,7 @@ static int vhost_vdpa_process_iotlb_msg(struct vhost_dev *dev,
> break;
> case VHOST_IOTLB_BATCH_END:
> if (v->in_batch && ops->set_map)
> - ops->set_map(vdpa, iotlb);
> + ops->set_map(vdpa, 0, iotlb);
> v->in_batch = false;
> break;
> default:
> @@ -1128,6 +1128,10 @@ static int vhost_vdpa_probe(struct vdpa_device *vdpa)
> int minor;
> int r;
>
> + /* Only support 1 address space and 1 groups */
> + if (vdpa->ngroups != 1 || vdpa->nas != 1)
> + return -EOPNOTSUPP;
> +
> v = kzalloc(sizeof(*v), GFP_KERNEL | __GFP_RETRY_MAYFAIL);
> if (!v)
> return -ENOMEM;
> diff --git a/include/linux/vdpa.h b/include/linux/vdpa.h
> index 026b7ad72ed7..de22ca1a8ef3 100644
> --- a/include/linux/vdpa.h
> +++ b/include/linux/vdpa.h
> @@ -69,6 +69,8 @@ struct vdpa_mgmt_dev;
> * @cf_mutex: Protects get and set access to configuration layout.
> * @index: device index
> * @features_valid: were features initialized? for legacy guests
> + * @ngroups: the number of virtqueue groups
> + * @nas: the number of address spaces
> * @use_va: indicate whether virtual address must be used by this device
> * @nvqs: maximum number of supported virtqueues
> * @mdev: management device pointer; caller must setup when registering device as part
> @@ -86,6 +88,7 @@ struct vdpa_device {
> int nvqs;
> struct vdpa_mgmt_dev *mdev;
> unsigned int ngroups;
> + unsigned int nas;
> };
>
> /**
> @@ -240,6 +243,7 @@ struct vdpa_map_file {
> * Needed for device that using device
> * specific DMA translation (on-chip IOMMU)
> * @vdev: vdpa device
> + * @asid: address space identifier
> * @iotlb: vhost memory mapping to be
> * used by the vDPA
> * Returns integer: success (0) or error (< 0)
> @@ -248,6 +252,7 @@ struct vdpa_map_file {
> * specific DMA translation (on-chip IOMMU)
> * and preferring incremental map.
> * @vdev: vdpa device
> + * @asid: address space identifier
> * @iova: iova to be mapped
> * @size: size of the area
> * @pa: physical address for the map
> @@ -259,6 +264,7 @@ struct vdpa_map_file {
> * specific DMA translation (on-chip IOMMU)
> * and preferring incremental unmap.
> * @vdev: vdpa device
> + * @asid: address space identifier
> * @iova: iova to be unmapped
> * @size: size of the area
> * Returns integer: success (0) or error (< 0)
> @@ -309,10 +315,12 @@ struct vdpa_config_ops {
> struct vdpa_iova_range (*get_iova_range)(struct vdpa_device *vdev);
>
> /* DMA ops */
> - int (*set_map)(struct vdpa_device *vdev, struct vhost_iotlb *iotlb);
> - int (*dma_map)(struct vdpa_device *vdev, u64 iova, u64 size,
> - u64 pa, u32 perm, void *opaque);
> - int (*dma_unmap)(struct vdpa_device *vdev, u64 iova, u64 size);
> + int (*set_map)(struct vdpa_device *vdev, unsigned int asid,
> + struct vhost_iotlb *iotlb);
> + int (*dma_map)(struct vdpa_device *vdev, unsigned int asid,
> + u64 iova, u64 size, u64 pa, u32 perm, void *opaque);
> + int (*dma_unmap)(struct vdpa_device *vdev, unsigned int asid,
> + u64 iova, u64 size);
>
> /* Free device resources */
> void (*free)(struct vdpa_device *vdev);
> @@ -320,7 +328,7 @@ struct vdpa_config_ops {
>
> struct vdpa_device *__vdpa_alloc_device(struct device *parent,
> const struct vdpa_config_ops *config,
> - unsigned int ngroups,
> + unsigned int ngroups, unsigned int nas,
> size_t size, const char *name,
> bool use_va);
>
> @@ -332,17 +340,19 @@ struct vdpa_device *__vdpa_alloc_device(struct device *parent,
> * @parent: the parent device
> * @config: the bus operations that is supported by this device
> * @ngroups: the number of virtqueue groups supported by this device
> + * @nas: the number of address spaces
> * @name: name of the vdpa device
> * @use_va: indicate whether virtual address must be used by this device
> *
> * Return allocated data structure or ERR_PTR upon error
> */
> -#define vdpa_alloc_device(dev_struct, member, parent, config, ngroups, name, use_va) \
> +#define vdpa_alloc_device(dev_struct, member, parent, config, ngroups, nas, \
> + name, use_va) \
> container_of((__vdpa_alloc_device( \
> - parent, config, ngroups, \
> - sizeof(dev_struct) + \
> + parent, config, ngroups, nas, \
> + (sizeof(dev_struct) + \

Maybe too nitpick or I'm missing something, but do we need to add the
parentheses around (sizeof(dev_struct) + BUILD_BUG_ON_ZERO(...)) ?

> BUILD_BUG_ON_ZERO(offsetof( \
> - dev_struct, member)), name, use_va)), \
> + dev_struct, member))), name, use_va)), \
> dev_struct, member)
>
> int vdpa_register_device(struct vdpa_device *vdev, int nvqs);
> --
> 2.25.0
>

Next message: Hao Luo: "Re: [PATCH bpf-next v1 4/9] bpf: Introduce sleepable tracepoints"
Previous message: Mike Rapoport: "Re: [PATCH 00/35] Shadow stacks for userspace"
Next in thread: Gautam Dawar: "RE: [RFC PATCH v2 06/19] vdpa: multiple address spaces support"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]