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path: root/drivers/dma-buf/udmabuf.c
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2019-12-18udmabuf: fix dma-buf cpu accessGurchetan Singh
I'm just going to put Chia's review comment here since it sums the issue rather nicely: "(1) Semantically, a dma-buf is in DMA domain. CPU access from the importer must be surrounded by {begin,end}_cpu_access. This gives the exporter a chance to move the buffer to the CPU domain temporarily. (2) When the exporter itself has other means to do CPU access, it is only reasonable for the exporter to move the buffer to the CPU domain before access, and to the DMA domain after access. The exporter can potentially reuse {begin,end}_cpu_access for that purpose. Because of (1), udmabuf does need to implement the {begin,end}_cpu_access hooks. But "begin" should mean dma_sync_sg_for_cpu and "end" should mean dma_sync_sg_for_device. Because of (2), if userspace wants to continuing accessing through the memfd mapping, it should call udmabuf's {begin,end}_cpu_access to avoid cache issues." Reported-by: Chia-I Wu <olvaffe@gmail.com> Suggested-by: Chia-I Wu <olvaffe@gmail.com> Fixes: 284562e1f348 ("udmabuf: implement begin_cpu_access/end_cpu_access hooks") Signed-off-by: Gurchetan Singh <gurchetansingh@chromium.org> Link: http://patchwork.freedesktop.org/patch/msgid/20191217230228.453-1-gurchetansingh@chromium.org Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2019-12-05udmabuf: implement begin_cpu_access/end_cpu_access hooksGurchetan Singh
With the misc device, we should end up using the result of get_arch_dma_ops(..) or dma-direct ops. This can allow us to have WC mappings in the guest after synchronization. Signed-off-by: Gurchetan Singh <gurchetansingh@chromium.org> Link: http://patchwork.freedesktop.org/patch/msgid/20191203013627.85991-4-gurchetansingh@chromium.org Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2019-12-05udmabuf: separate out creating/destroying scatter-tableGurchetan Singh
These are nice functions and can be re-used. Signed-off-by: Gurchetan Singh <gurchetansingh@chromium.org> Link: http://patchwork.freedesktop.org/patch/msgid/20191203013627.85991-3-gurchetansingh@chromium.org Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2019-12-05udmabuf: add a pointer to the miscdevice in dma-buf private dataGurchetan Singh
Will be used later. v2: rename 'udmabuf_misc' to 'device' (kraxel) Signed-off-by: Gurchetan Singh <gurchetansingh@chromium.org> Link: http://patchwork.freedesktop.org/patch/msgid/20191203013627.85991-2-gurchetansingh@chromium.org Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2019-12-05udmabuf: use cache_sgt_mapping optionGurchetan Singh
The GEM prime helpers do it, so should we. It's also possible to make it optional later. Signed-off-by: Gurchetan Singh <gurchetansingh@chromium.org> Link: http://patchwork.freedesktop.org/patch/msgid/20191203013627.85991-1-gurchetansingh@chromium.org Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2019-11-26udmabuf: Remove deleted map/unmap handlers.Maarten Lankhorst
Commit 7f0de8d80816 ("dma-buf: Drop dma_buf_k(un)map") removed map/unmap handlers, but they still existed in udmabuf. Remove them there as well Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Fixes: 7f0de8d80816 ("dma-buf: Drop dma_buf_k(un)map") Cc: Sumit Semwal <sumit.semwal@linaro.org> Cc: Daniel Vetter <daniel.vetter@intel.com> Cc: linux-media@vger.kernel.org Cc: linaro-mm-sig@lists.linaro.org Cc: dri-devel@lists.freedesktop.org Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: https://patchwork.freedesktop.org/patch/msgid/20191126142516.630200-1-maarten.lankhorst@linux.intel.com
2019-06-05udmabuf: actually unmap the scatterlistLucas Stach
unmap_udmabuf fails to actually unmap the scatterlist, leaving dangling mappings around. Fixes: fbb0de795078 ("Add udmabuf misc device") Signed-off-by: Lucas Stach <l.stach@pengutronix.de> Link: http://patchwork.freedesktop.org/patch/msgid/20190604202331.17482-1-l.stach@pengutronix.de Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2019-01-04drivers/dma-buf/udmabuf.c: convert to use vm_fault_tSouptick Joarder
Use new return type vm_fault_t for fault handler. Link: http://lkml.kernel.org/r/20181106173628.GA12989@jordon-HP-15-Notebook-PC Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com> Cc: Gerd Hoffmann <kraxel@redhat.com> Cc: Sumit Semwal <sumit.semwal@linaro.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-11-16udmabuf: set read/write flag when exportingGerd Hoffmann
Otherwise, mmap fails when done with PROT_WRITE. Suggested-by: Gurchetan Singh <gurchetansingh@chromium.org> Signed-off-by: Gerd Hoffmann <kraxel@redhat.com> Reviewed-by: Gurchetan Singh <gurchetansingh@chromium.org> Tested-by: Gurchetan Singh <gurchetansingh@chromium.org> Link: http://patchwork.freedesktop.org/patch/msgid/20181114122029.16766-1-kraxel@redhat.com
2018-09-14udmabuf: fix error code in map_udmabuf()Dan Carpenter
We accidentally forgot to set "ret" on this error path so it means we return NULL instead of an error pointer. The caller checks for NULL and changes it to an error pointer so it doesn't cause an issue at run time. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Link: http://patchwork.freedesktop.org/patch/msgid/20180914065615.GA12043@mwanda Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2018-09-12udmabuf: use sizeof(variable) instead of sizeof(type)Gerd Hoffmann
Reported-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Gerd Hoffmann <kraxel@redhat.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Link: http://patchwork.freedesktop.org/patch/msgid/20180911134216.9760-13-kraxel@redhat.com
2018-09-12udmabuf: drop WARN_ON() check.Gerd Hoffmann
Reported-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Gerd Hoffmann <kraxel@redhat.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Link: http://patchwork.freedesktop.org/patch/msgid/20180911134216.9760-12-kraxel@redhat.com
2018-09-12udmabuf: use ENOTTY for invalid ioctlsGerd Hoffmann
Reported-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Gerd Hoffmann <kraxel@redhat.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: http://patchwork.freedesktop.org/patch/msgid/20180911134216.9760-11-kraxel@redhat.com
2018-09-12udmabuf: use EBADFD in case we didn't got a memfdGerd Hoffmann
Reported-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Gerd Hoffmann <kraxel@redhat.com> Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: http://patchwork.freedesktop.org/patch/msgid/20180911134216.9760-10-kraxel@redhat.com
2018-09-12udmabuf: improve udmabuf_create error handlingGerd Hoffmann
Reported-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Gerd Hoffmann <kraxel@redhat.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: http://patchwork.freedesktop.org/patch/msgid/20180911134216.9760-9-kraxel@redhat.com
2018-09-12udmabuf: rework limitsGerd Hoffmann
Create variable for the list length limit. Serves as documentation, also allows to make it a module parameter if needed. Also add a total size limit. Signed-off-by: Gerd Hoffmann <kraxel@redhat.com> Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: http://patchwork.freedesktop.org/patch/msgid/20180911134216.9760-8-kraxel@redhat.com
2018-09-12udmabuf: constify udmabuf_create argsGerd Hoffmann
Reported-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Gerd Hoffmann <kraxel@redhat.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: http://patchwork.freedesktop.org/patch/msgid/20180911134216.9760-6-kraxel@redhat.com
2018-09-12udmabuf: constify udmabuf_opsGerd Hoffmann
Reported-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Gerd Hoffmann <kraxel@redhat.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: http://patchwork.freedesktop.org/patch/msgid/20180911134216.9760-5-kraxel@redhat.com
2018-09-12udmabuf: use pgoff_t for pagecountGerd Hoffmann
Reported-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Gerd Hoffmann <kraxel@redhat.com> Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: http://patchwork.freedesktop.org/patch/msgid/20180911134216.9760-4-kraxel@redhat.com
2018-09-12udmabuf: improve map_udmabuf error handlingGerd Hoffmann
Reported-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Gerd Hoffmann <kraxel@redhat.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: http://patchwork.freedesktop.org/patch/msgid/20180911134216.9760-3-kraxel@redhat.com
2018-09-12udmabuf: sort headers, drop uapi/ path prefixGerd Hoffmann
Reported-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Gerd Hoffmann <kraxel@redhat.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: http://patchwork.freedesktop.org/patch/msgid/20180911134216.9760-2-kraxel@redhat.com
2018-09-05dma-buf/udmabuf: Fix NULL pointer dereference in udmabuf_createGustavo A. R. Silva
There is a potential execution path in which pointer memfd is NULL when passed as argument to fput(), hence there is a NULL pointer dereference in fput(). Fix this by null checking *memfd* before calling fput(). Addresses-Coverity-ID: 1473174 ("Explicit null dereferenced") Fixes: fbb0de795078 ("Add udmabuf misc device") Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Link: http://patchwork.freedesktop.org/patch/msgid/20180904190749.GA9308@embeddedor.com Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2018-09-03Add udmabuf misc deviceGerd Hoffmann
A driver to let userspace turn memfd regions into dma-bufs. Use case: Allows qemu create dmabufs for the vga framebuffer or virtio-gpu ressources. Then they can be passed around to display those guest things on the host. To spice client for classic full framebuffer display, and hopefully some day to wayland server for seamless guest window display. qemu test branch: https://git.kraxel.org/cgit/qemu/log/?h=sirius/udmabuf Cc: David Airlie <airlied@linux.ie> Cc: Tomeu Vizoso <tomeu.vizoso@collabora.com> Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Cc: Daniel Vetter <daniel@ffwll.ch> Signed-off-by: Gerd Hoffmann <kraxel@redhat.com> Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: http://patchwork.freedesktop.org/patch/msgid/20180827093444.23623-1-kraxel@redhat.com