On Thu, Oct 29, 2020 at 7:20 PM Jason Gunthorpe jgg@nvidia.com wrote:
On Wed, Oct 28, 2020 at 08:49:11PM +0100, Daniel Vetter wrote:
On Wed, Oct 28, 2020 at 04:15:26PM -0300, Jason Gunthorpe wrote:
Since commit 9a40401cfa13 ("lib/scatterlist: Do not limit max_segment to PAGE_ALIGNED values") the max_segment input to sg_alloc_table_from_pages() does not have to be any special value. The new algorithm will always create something less than what the user provides. Thus eliminate this confusing constant.
vmwgfx should use the HW capability, not mix in the OS page size for calling dma_set_max_seg_size()
i915 uses i915_sg_segment_size() both for sg_alloc_table_from_pages and for some open coded sgl construction. This doesn't change the value since rounddown(size, UINT_MAX) == SCATTERLIST_MAX_SEGMENT
drm_prime_pages_to_sg uses it as a default if max_segment is zero, UINT_MAX is fine to use directly.
Cc: Gerd Hoffmann kraxel@redhat.com Cc: Daniel Vetter daniel.vetter@ffwll.ch Cc: Thomas Hellstrom thellstrom@vmware.com Cc: Qian Cai cai@lca.pw Cc: "Ursulin, Tvrtko" tvrtko.ursulin@intel.com Suggested-by: Christoph Hellwig hch@lst.de Signed-off-by: Jason Gunthorpe jgg@nvidia.com
lgtm. Do you want to push this through some other queue, or should I put this into drm trees? Prefer 5.10 or 5.11?
I think DRM tree is best
Ok, I'll try to remember and apply this to -next after -rc2. -rc1 is supremely busted for us, I want to wait with pulling the merge window into the -next pile until that's settled. Please ping if your patch isn't in linux-next within a week in case I forget. -Daniel