kernel/linux.git/drivers/vdpa/mlx5, branch v6.7

vdpa/mlx5: preserve CVQ vringh index

2023-12-01T14:52:03+00:00

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: 5262912ef3cf ("vdpa/mlx5: Add support for control VQ and MAC setting") Signed-off-by: Steve Sistare Acked-by: Eugenio Pérez Acked-by: Jason Wang Message-Id: <1699014387-194368-1-git-send-email-steven.sistare@oracle.com> Signed-off-by: Michael S. Tsirkin

vdpa/mlx5: implement .reset_map driver op

2023-11-01T13:20:00+00:00

Since commit 6f5312f80183 ("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 Signed-off-by: Dragos Tatulea Signed-off-by: Si-Wei Liu Message-Id: <1697880319-4937-7-git-send-email-si-wei.liu@oracle.com> Signed-off-by: Michael S. Tsirkin Tested-by: Lei Yang

mlx5_vdpa: offer VHOST_BACKEND_F_ENABLE_AFTER_DRIVER_OK

2023-11-01T13:19:58+00:00

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 Message-Id: <20230703142514.363256-1-eperezma@redhat.com> Signed-off-by: Michael S. Tsirkin

vdpa/mlx5: Update cvq iotlb mapping on ASID change

2023-11-01T13:19:57+00:00

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 Acked-by: Eugenio Pérez Signed-off-by: Dragos Tatulea Message-Id: <20231018171456.1624030-18-dtatulea@nvidia.com> Signed-off-by: Michael S. Tsirkin Reviewed-by: Si-Wei Liu Tested-by: Si-Wei Liu Tested-by: Lei Yang

vdpa/mlx5: Make iotlb helper functions more generic

2023-11-01T13:19:57+00:00

They will be used in a follow-up patch. For dup_iotlb, avoid the src == dst case. This is an error. Acked-by: Jason Wang Acked-by: Eugenio Pérez Signed-off-by: Dragos Tatulea Message-Id: <20231018171456.1624030-17-dtatulea@nvidia.com> Signed-off-by: Michael S. Tsirkin Reviewed-by: Si-Wei Liu Tested-by: Si-Wei Liu Tested-by: Lei Yang

vdpa/mlx5: Enable hw support for vq descriptor mapping

2023-11-01T13:19:57+00:00

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 Acked-by: Eugenio Pérez Signed-off-by: Dragos Tatulea Message-Id: <20231018171456.1624030-16-dtatulea@nvidia.com> Signed-off-by: Michael S. Tsirkin Reviewed-by: Si-Wei Liu Tested-by: Si-Wei Liu Tested-by: Lei Yang

vdpa/mlx5: Introduce mr for vq descriptor

2023-11-01T13:19:57+00:00

Introduce the vq descriptor group and mr per ASID. Until now .set_map on ASID 1 was only updating the cvq iotlb. From now on it also creates a mkey for it. The current patch doesn't use it but follow-up patches will add hardware support for mapping the vq descriptors. Acked-by: Jason Wang Acked-by: Eugenio Pérez Signed-off-by: Dragos Tatulea Message-Id: <20231018171456.1624030-15-dtatulea@nvidia.com> Signed-off-by: Michael S. Tsirkin Reviewed-by: Si-Wei Liu Tested-by: Si-Wei Liu Tested-by: Lei Yang

vdpa/mlx5: Improve mr update flow

2023-11-01T13:19:57+00:00

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 Acked-by: Jason Wang Signed-off-by: Dragos Tatulea Message-Id: <20231018171456.1624030-14-dtatulea@nvidia.com> Signed-off-by: Michael S. Tsirkin Reviewed-by: Si-Wei Liu Tested-by: Si-Wei Liu Tested-by: Lei Yang

vdpa/mlx5: Move mr mutex out of mr struct

2023-11-01T13:19:56+00:00

The mutex is named like it is supposed to protect only the mkey but in reality it is a global lock for all mr resources. Shift the mutex to it's rightful location (struct mlx5_vdpa_dev) and give it a more appropriate name. Signed-off-by: Dragos Tatulea Acked-by: Eugenio Pérez Acked-by: Jason Wang Message-Id: <20231018171456.1624030-13-dtatulea@nvidia.com> Signed-off-by: Michael S. Tsirkin Reviewed-by: Si-Wei Liu Tested-by: Si-Wei Liu Tested-by: Lei Yang

vdpa/mlx5: Allow creation/deletion of any given mr struct

2023-11-01T13:19:56+00:00

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 Acked-by: Eugenio Pérez Acked-by: Jason Wang Message-Id: <20231018171456.1624030-12-dtatulea@nvidia.com> Signed-off-by: Michael S. Tsirkin Reviewed-by: Si-Wei Liu Tested-by: Si-Wei Liu Tested-by: Lei Yang