It's desirable to use zero-copy mechanisms when using various graphics buffers. With udmabuf, two cases come to mind: 1) Directly scan-out a guest-mapped buffer 2) Import into VK with VK_EXT_external_memory_dma_buf However, displays are not generally coherent with the CPU and many GPUs aren't either. So we need to map write-combine in the guest. One way to achieve this is to synchronize on the host. [warning] -- only compile tested at this point to get feedback Gurchetan Singh (6): udmabuf: use cache_sgt_mapping option udmabuf: add ability to set access flags on udmabuf udmabuf: enforce access flags udmabuf: add a pointer to the miscdevice in dma-buf private data udmabuf: separate out creating/destroying scatter-table udmabuf: implement begin_cpu_access/end_cpu_access hooks drivers/dma-buf/udmabuf.c | 103 +++++++++++++++++++++++++++++------ include/uapi/linux/udmabuf.h | 5 +- 2 files changed, 90 insertions(+), 18 deletions(-) -- 2.17.1 _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
