On Thu, Sep 17, 2020 at 06:06:14PM +0200, Christian König wrote:
If it is already taking a page fault I'm not sure the extra function call indirection is going to be a big deal. Having a uniform VMA sounds saner than every driver custom rolling something.
When I unwound a similar mess in RDMA all the custom VMA stuff in the drivers turned out to be generally buggy, at least.
Is vma->vm_file->private_data universally a dma_buf pointer at least?
Nope. I think if you want this without some large scale rewrite of a lot of code we'd need a vmops->get_dmabuf or similar. Not pretty, but would get the job done.
Yeah, agree that sounds like the simplest approach.
I don't think that will fly, it is clearly only papering over a mess inside DRM/dma buf :\
Jason