Proposal to make it type safe, never casting to void, but allow the backend to use whatever struct it needs.
Next patches will move the token from a domain to a custom struct. Signed-off-by: Eugenio Pérez <[email protected]> --- drivers/vdpa/vdpa_user/iova_domain.h | 1 + drivers/vdpa/vdpa_user/vduse_dev.c | 60 ++++++++++++++++------------ drivers/virtio/virtio_ring.c | 6 ++- include/linux/virtio.h | 8 +++- include/linux/virtio_config.h | 34 +++++++++------- 5 files changed, 67 insertions(+), 42 deletions(-) diff --git a/drivers/vdpa/vdpa_user/iova_domain.h b/drivers/vdpa/vdpa_user/iova_domain.h index 1f3c30be272a..c0f97dfaf94f 100644 --- a/drivers/vdpa/vdpa_user/iova_domain.h +++ b/drivers/vdpa/vdpa_user/iova_domain.h @@ -26,6 +26,7 @@ struct vduse_bounce_map { }; struct vduse_iova_domain { + struct vring_mapping_opaque token; struct iova_domain stream_iovad; struct iova_domain consistent_iovad; struct vduse_bounce_map *bounce_maps; diff --git a/drivers/vdpa/vdpa_user/vduse_dev.c b/drivers/vdpa/vdpa_user/vduse_dev.c index e42d14888ca2..e3c8fc1aa446 100644 --- a/drivers/vdpa/vdpa_user/vduse_dev.c +++ b/drivers/vdpa/vdpa_user/vduse_dev.c @@ -164,6 +164,11 @@ static inline struct vduse_dev *dev_to_vduse(struct device *dev) return vdpa_to_vduse(vdpa); } +static struct vduse_iova_domain *vduse_token_to_domain(struct vring_mapping_opaque *token) +{ + return container_of(token, struct vduse_iova_domain, token); +} + static struct vduse_dev_msg *vduse_find_msg(struct list_head *head, uint32_t request_id) { @@ -854,47 +859,50 @@ static const struct vdpa_config_ops vduse_vdpa_config_ops = { .free = vduse_vdpa_free, }; -static void vduse_dev_sync_single_for_device(void *token, +static void vduse_dev_sync_single_for_device(struct vring_mapping_opaque *token, dma_addr_t dma_addr, size_t size, enum dma_data_direction dir) { - struct vduse_iova_domain *domain = token; + struct vduse_iova_domain *domain = vduse_token_to_domain(token); vduse_domain_sync_single_for_device(domain, dma_addr, size, dir); } -static void vduse_dev_sync_single_for_cpu(void *token, - dma_addr_t dma_addr, size_t size, - enum dma_data_direction dir) +static void vduse_dev_sync_single_for_cpu(struct vring_mapping_opaque *token, + dma_addr_t dma_addr, size_t size, + enum dma_data_direction dir) { - struct vduse_iova_domain *domain = token; + struct vduse_iova_domain *domain = vduse_token_to_domain(token); vduse_domain_sync_single_for_cpu(domain, dma_addr, size, dir); } -static dma_addr_t vduse_dev_map_page(void *token, struct page *page, +static dma_addr_t vduse_dev_map_page(struct vring_mapping_opaque *token, + struct page *page, unsigned long offset, size_t size, enum dma_data_direction dir, unsigned long attrs) { - struct vduse_iova_domain *domain = token; + struct vduse_iova_domain *domain = vduse_token_to_domain(token); return vduse_domain_map_page(domain, page, offset, size, dir, attrs); } -static void vduse_dev_unmap_page(void *token, dma_addr_t dma_addr, - size_t size, enum dma_data_direction dir, - unsigned long attrs) +static void vduse_dev_unmap_page(struct vring_mapping_opaque *token, + dma_addr_t dma_addr, size_t size, + enum dma_data_direction dir, + unsigned long attrs) { - struct vduse_iova_domain *domain = token; + struct vduse_iova_domain *domain = vduse_token_to_domain(token); return vduse_domain_unmap_page(domain, dma_addr, size, dir, attrs); } -static void *vduse_dev_alloc_coherent(void *token, size_t size, - dma_addr_t *dma_addr, gfp_t flag) +static void *vduse_dev_alloc_coherent(struct vring_mapping_opaque *token, + size_t size, dma_addr_t *dma_addr, + gfp_t flag) { - struct vduse_iova_domain *domain = token; + struct vduse_iova_domain *domain = vduse_token_to_domain(token); unsigned long iova; void *addr; @@ -909,32 +917,34 @@ static void *vduse_dev_alloc_coherent(void *token, size_t size, return addr; } -static void vduse_dev_free_coherent(void *token, size_t size, - void *vaddr, dma_addr_t dma_addr, - unsigned long attrs) +static void vduse_dev_free_coherent(struct vring_mapping_opaque *token, + size_t size, void *vaddr, + dma_addr_t dma_addr, unsigned long attrs) { - struct vduse_iova_domain *domain = token; + struct vduse_iova_domain *domain = vduse_token_to_domain(token); vduse_domain_free_coherent(domain, size, vaddr, dma_addr, attrs); } -static bool vduse_dev_need_sync(void *token, dma_addr_t dma_addr) +static bool vduse_dev_need_sync(struct vring_mapping_opaque *token, + dma_addr_t dma_addr) { - struct vduse_iova_domain *domain = token; + struct vduse_iova_domain *domain = vduse_token_to_domain(token); return dma_addr < domain->bounce_size; } -static int vduse_dev_mapping_error(void *token, dma_addr_t dma_addr) +static int vduse_dev_mapping_error(struct vring_mapping_opaque *token, + dma_addr_t dma_addr) { if (unlikely(dma_addr == DMA_MAPPING_ERROR)) return -ENOMEM; return 0; } -static size_t vduse_dev_max_mapping_size(void *token) +static size_t vduse_dev_max_mapping_size(struct vring_mapping_opaque *token) { - struct vduse_iova_domain *domain = token; + struct vduse_iova_domain *domain = vduse_token_to_domain(token); return domain->bounce_size; } @@ -2103,7 +2113,7 @@ static int vdpa_dev_add(struct vdpa_mgmt_dev *mdev, const char *name, return -ENOMEM; } - dev->vdev->vdpa.mapping_token.token = dev->domain; + dev->vdev->vdpa.mapping_token.token = &dev->domain->token; ret = _vdpa_register_device(&dev->vdev->vdpa, dev->vq_num); if (ret) { put_device(&dev->vdev->vdpa.dev); diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c index fc0f5faa8523..4fc588458b23 100644 --- a/drivers/virtio/virtio_ring.c +++ b/drivers/virtio/virtio_ring.c @@ -349,8 +349,12 @@ size_t virtio_max_dma_size(const struct virtio_device *vdev) if (vring_use_map_api(vdev)) { if (vdev->map) + /* + * TODO we should be able to get the token here, not + * cast to void + */ max_segment_size = - vdev->map->max_mapping_size(vdev->dev.parent); + vdev->map->max_mapping_size((void *)vdev->dev.parent); else max_segment_size = dma_max_mapping_size(vdev->dev.parent); diff --git a/include/linux/virtio.h b/include/linux/virtio.h index ceca93348aed..c446c511b8c1 100644 --- a/include/linux/virtio.h +++ b/include/linux/virtio.h @@ -40,11 +40,17 @@ struct virtqueue { void *priv; }; +/* + * Base struct for the transport specific token used for doing map. + * It allows to convert between the transport specific type to the mapping + * token with a valud type always. + */ +struct vring_mapping_opaque {}; union vring_mapping_token { /* Device that performs DMA */ struct device *dma_dev; /* Transport specific token used for doing map */ - void *token; + struct vring_mapping_opaque *token; }; int virtqueue_add_outbuf(struct virtqueue *vq, diff --git a/include/linux/virtio_config.h b/include/linux/virtio_config.h index 4566ac87feb7..02d98fb1309c 100644 --- a/include/linux/virtio_config.h +++ b/include/linux/virtio_config.h @@ -191,24 +191,28 @@ struct virtio_config_ops { * Returns: the maximum buffer size that can be mapped */ struct virtio_map_ops { - dma_addr_t (*map_page)(void *token, struct page *page, - unsigned long offset, size_t size, - enum dma_data_direction dir, unsigned long attrs); - void (*unmap_page)(void *token, dma_addr_t map_handle, - size_t size, enum dma_data_direction dir, - unsigned long attrs); - void (*sync_single_for_cpu)(void *token, dma_addr_t map_handle, - size_t size, enum dma_data_direction dir); - void (*sync_single_for_device)(void *token, + dma_addr_t (*map_page)(struct vring_mapping_opaque *token, + struct page *page, unsigned long offset, + size_t size, enum dma_data_direction dir, + unsigned long attrs); + void (*unmap_page)(struct vring_mapping_opaque *token, + dma_addr_t map_handle, size_t size, + enum dma_data_direction dir, unsigned long attrs); + void (*sync_single_for_cpu)(struct vring_mapping_opaque *token, + dma_addr_t map_handle, size_t size, + enum dma_data_direction dir); + void (*sync_single_for_device)(struct vring_mapping_opaque *token, dma_addr_t map_handle, size_t size, enum dma_data_direction dir); - void *(*alloc)(void *token, size_t size, + void *(*alloc)(struct vring_mapping_opaque *token, size_t size, dma_addr_t *map_handle, gfp_t gfp); - void (*free)(void *token, size_t size, void *vaddr, - dma_addr_t map_handle, unsigned long attrs); - bool (*need_sync)(void *token, dma_addr_t map_handle); - int (*mapping_error)(void *token, dma_addr_t map_handle); - size_t (*max_mapping_size)(void *token); + void (*free)(struct vring_mapping_opaque *token, size_t size, + void *vaddr, dma_addr_t map_handle, unsigned long attrs); + bool (*need_sync)(struct vring_mapping_opaque *token, + dma_addr_t map_handle); + int (*mapping_error)(struct vring_mapping_opaque *token, + dma_addr_t map_handle); + size_t (*max_mapping_size)(struct vring_mapping_opaque *token); }; /* If driver didn't advertise the feature, it will never appear. */ -- 2.50.1
