Linaro-mm-sig June 2018

linaro-mm-sig@lists.linaro.org

14 participants
22 discussions

Re: [Linaro-mm-sig] [PATCH 1/5] dma_buf: remove device parameter from attach callback

by Christian König

Am 01.06.2018 um 16:02 schrieb Michel Dänzer: > On 2018-06-01 02:11 PM, Christian König wrote: >> Sorry, accidentally send this series without a cover letter. >> >> This is a cleanup to the DMA-buf interface, which is also a prerequisite >> to unpinned DMA-buf operation. >> >> Patch #1 and #2 just remove unused functionality and clean up callback >> parameters. >> >> Patch #3 and #4 introduce taking the reservation lock during >> mapping/unmapping of DMA-bufs. >> >> This introduces a common lock where both exporter as well as importer >> can then use in the future for unpinned DMA-buf operation. >> >> This of course means that exporters should now not take this reservation >> lock manually any more. The DRM drivers don't seem to actually do that, >> but I'm not 100% sure about other implementations. >> >> Patch #5 then makes use of the new lock to simplify the DMA-buf import >> handling in amdgpu. > Please rebase this series on top of > https://patchwork.freedesktop.org/patch/226311/ and update the > documentation in amdgpu_prime.c as needed in each patch. Sure. In this case can we get your patches committed to amd-staging-drm-next ASAP? Thanks, Christian.

6 years, 6 months

[PATCH] dma-buf: make map_atomic and map function pointers optional

by Gerd Hoffmann

So drivers don't need dummy functions just returning NULL. Cc: Daniel Vetter <daniel(a)ffwll.ch> Signed-off-by: Gerd Hoffmann <kraxel(a)redhat.com> --- include/linux/dma-buf.h | 4 ++-- drivers/dma-buf/dma-buf.c | 4 ++++ 2 files changed, 6 insertions(+), 2 deletions(-) diff --git a/include/linux/dma-buf.h b/include/linux/dma-buf.h index 085db2fee2..88917fa796 100644 --- a/include/linux/dma-buf.h +++ b/include/linux/dma-buf.h @@ -39,12 +39,12 @@ struct dma_buf_attachment; /** * struct dma_buf_ops - operations possible on struct dma_buf - * @map_atomic: maps a page from the buffer into kernel address + * @map_atomic: [optional] maps a page from the buffer into kernel address * space, users may not block until the subsequent unmap call. * This callback must not sleep. * @unmap_atomic: [optional] unmaps a atomically mapped page from the buffer. * This Callback must not sleep. - * @map: maps a page from the buffer into kernel address space. + * @map: [optional] maps a page from the buffer into kernel address space. * @unmap: [optional] unmaps a page from the buffer. * @vmap: [optional] creates a virtual mapping for the buffer into kernel * address space. Same restrictions as for vmap and friends apply. diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c index d78d5fc173..4c45e31258 100644 --- a/drivers/dma-buf/dma-buf.c +++ b/drivers/dma-buf/dma-buf.c @@ -872,6 +872,8 @@ void *dma_buf_kmap_atomic(struct dma_buf *dmabuf, unsigned long page_num) { WARN_ON(!dmabuf); + if (!dmabuf->ops->map_atomic) + return NULL; return dmabuf->ops->map_atomic(dmabuf, page_num); } EXPORT_SYMBOL_GPL(dma_buf_kmap_atomic); @@ -907,6 +909,8 @@ void *dma_buf_kmap(struct dma_buf *dmabuf, unsigned long page_num) { WARN_ON(!dmabuf); + if (!dmabuf->ops->map) + return NULL; return dmabuf->ops->map(dmabuf, page_num); } EXPORT_SYMBOL_GPL(dma_buf_kmap); -- 2.9.3

6 years, 6 months

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Linaro-mm-sig June 2018