On Thu, Feb 07, 2019 at 10:26:52PM +0000, Jason Gunthorpe wrote: > Commit 2db76d7c3c6d ("lib/scatterlist: sg_page_iter: support sg lists w/o > backing pages") introduced the sg_page_iter_dma_address() function without > providing a way to use it in the general case. If the sg_dma_len() is not > equal to the sg length callers cannot safely use the > for_each_sg_page/sg_page_iter_dma_address combination. > > Resolve this API mistake by providing a DMA specific iterator, > for_each_sg_dma_page(), that uses the right length so > sg_page_iter_dma_address() works as expected with all sglists. > > A new iterator type is introduced to provide compile-time safety against > wrongly mixing accessors and iterators. > > Acked-by: Christoph Hellwig <hch@xxxxxx> (for scatterlist) > Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxxxx> > Acked-by: Thomas Hellstrom <thellstrom@xxxxxxxxxx> > --- > .clang-format | 1 + > drivers/gpu/drm/vmwgfx/vmwgfx_ttm_buffer.c | 8 +++- > drivers/media/pci/intel/ipu3/ipu3-cio2.c | 4 +- > include/linux/scatterlist.h | 49 ++++++++++++++++++---- > lib/scatterlist.c | 26 ++++++++++++ > 5 files changed, 76 insertions(+), 12 deletions(-) Applied to rdma.git's for-next, thanks everyone. Jason