From d7b4e3287ca3a7baf66efd9158498e551a9550da Mon Sep 17 00:00:00 2001 From: Maxime Coquelin Date: Mon, 19 Feb 2024 18:06:06 +0100 Subject: vduse: implement DMA sync callbacks Since commit 295525e29a5b ("virtio_net: merge dma operations when filling mergeable buffers"), VDUSE device require support for DMA's .sync_single_for_cpu() operation as the memory is non-coherent between the device and CPU because of the use of a bounce buffer. This patch implements both .sync_single_for_cpu() and .sync_single_for_device() callbacks, and also skip bounce buffer copies during DMA map and unmap operations if the DMA_ATTR_SKIP_CPU_SYNC attribute is set to avoid extra copies of the same buffer. Signed-off-by: Maxime Coquelin Message-Id: <20240219170606.587290-1-maxime.coquelin@redhat.com> Signed-off-by: Michael S. Tsirkin --- drivers/vdpa/vdpa_user/vduse_dev.c | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) (limited to 'drivers/vdpa/vdpa_user/vduse_dev.c') diff --git a/drivers/vdpa/vdpa_user/vduse_dev.c b/drivers/vdpa/vdpa_user/vduse_dev.c index 1d24da79c399..75354ce186a1 100644 --- a/drivers/vdpa/vdpa_user/vduse_dev.c +++ b/drivers/vdpa/vdpa_user/vduse_dev.c @@ -798,6 +798,26 @@ static const struct vdpa_config_ops vduse_vdpa_config_ops = { .free = vduse_vdpa_free, }; +static void vduse_dev_sync_single_for_device(struct device *dev, + dma_addr_t dma_addr, size_t size, + enum dma_data_direction dir) +{ + struct vduse_dev *vdev = dev_to_vduse(dev); + struct vduse_iova_domain *domain = vdev->domain; + + vduse_domain_sync_single_for_device(domain, dma_addr, size, dir); +} + +static void vduse_dev_sync_single_for_cpu(struct device *dev, + dma_addr_t dma_addr, size_t size, + enum dma_data_direction dir) +{ + struct vduse_dev *vdev = dev_to_vduse(dev); + struct vduse_iova_domain *domain = vdev->domain; + + vduse_domain_sync_single_for_cpu(domain, dma_addr, size, dir); +} + static dma_addr_t vduse_dev_map_page(struct device *dev, struct page *page, unsigned long offset, size_t size, enum dma_data_direction dir, @@ -858,6 +878,8 @@ static size_t vduse_dev_max_mapping_size(struct device *dev) } static const struct dma_map_ops vduse_dev_dma_ops = { + .sync_single_for_device = vduse_dev_sync_single_for_device, + .sync_single_for_cpu = vduse_dev_sync_single_for_cpu, .map_page = vduse_dev_map_page, .unmap_page = vduse_dev_unmap_page, .alloc = vduse_dev_alloc_coherent, -- cgit v1.2.3