On Fri, Oct 18, 2013 at 11:00:57AM +0200, benjamin.gaignard@linaro.org wrote:
From: Benjamin Gaignard benjamin.gaignard@linaro.org
DRM already offer helpers to use CMA for dumb buffers. This patch add helpers to export/import gem_cam objects and allow them to be mmap from userland. The goal is to make working this kind of sequence: create_dumb, get fd from buffer handle and then use fd (maybe in another process which may ignore it is comming from DRM) to mmap the buffer.
drm_gem_cma_prime_export() add O_RDWR to flags to be sure that memory could be mmapped later with PROT_WRITE flag.
Signed-off-by: Benjamin Gaignard benjamin.gaignard@linaro.org
[snip]
+struct dma_buf *drm_gem_cma_prime_export(struct drm_device *drm_dev,
struct drm_gem_object *obj, int flags)+{
- struct drm_gem_cma_object *cma_obj = to_drm_gem_cma_obj(obj);
- flags |= O_RDWR;
This here looks funny ... I think either we need to add more flags to the prime dma-buf exporting to also pass this flag through. Or we should just generally set this in dma_buf_export. Doing this as an exporter-specific hack feels wrong. -Daniel
- return dma_buf_export(cma_obj, &drm_gem_cma_dmabuf_ops,
cma_obj->base.size, flags);+} +EXPORT_SYMBOL_GPL(drm_gem_cma_prime_export);