[Intel-gfx] [PATCH v10] drm/i915/gvt: Dma-buf support for GVT-g

[Zhang, Tina]

Hi, 

This is the version 10 ABI interface. I took Gerd's advice to submit the interface only. If everything is fine, I can submit the whole patch set.
So, how do you think about this ABI interface.
Thanks.

BR,
Tina

> -----Original Message-----
> From: intel-gvt-dev [mailto:intel-gvt-dev-bounces at lists.freedesktop.org] On
> Behalf Of Tina Zhang
> Sent: Thursday, July 6, 2017 6:30 AM
> To: alex.williamson at redhat.com; kraxel at redhat.com; chris at chris-wilson.co.uk;
> zhenyuw at linux.intel.com; Lv, Zhiyuan <zhiyuan.lv at intel.com>; Wang, Zhi A
> <zhi.a.wang at intel.com>; Tian, Kevin <kevin.tian at intel.com>; daniel at ffwll.ch;
> kwankhede at nvidia.com
> Cc: intel-gfx at lists.freedesktop.org; intel-gvt-dev at lists.freedesktop.org; linux-
> kernel at vger.kernel.org; Zhang, Tina <tina.zhang at intel.com>
> Subject: [PATCH v10] drm/i915/gvt: Dma-buf support for GVT-g
> 
> 
> v9->v10:
> 1) remove dma-buf management
> 2) refine the ABI API VFIO_DEVICE_QUERY_GFX_PLANE
> 3) track the dma-buf create and release in kernel mode
> 
> v8->v9:
> 1) refine the dma-buf ioctl definition
> 2) add a lock to protect the dmabuf list
> 3) move drm format change to a separate patch
> 4) codes cleanup
> 
> v7->v8:
> 1) refine framebuffer decoder code
> 2) fix a bug in decoding primary plane
> 
> v6->v7:
> 1) release dma-buf related allocations in dma-buf's associated release function.
> 2) refine ioctl interface for querying plane info or create dma-buf
> 3) refine framebuffer decoder code
> 4) the patch series is based on 4.12.0-rc1
> 
> v5->v6:
> 1) align the dma-buf life cycle with the vfio device.
> 2) add the dma-buf releated operations in a separate patch.
> 3) i915 releated changes.
> 
> v4->v5:
> 1) fix bug while checking whether the gem obj is gvt's dma-buf when user
> change caching mode or domains. Add a helper function to do it.
> 2) add definition for the query plane and create dma-buf.
> 
> v3->v4:
> 1) fix bug while checking whether the gem obj is gvt's dma-buf when set caching
> mode or doamins.
> 
> v2->v3:
> 1) add a field gvt_plane_info in the drm_i915_gem_obj structure to save the
> decoded plane information to avoid look up while need the plane info.
> 2) declare a new flag I915_GEM_OBJECT_IS_GVT_DMABUF in
> drm_i915_gem_object to represent the gem obj for gvt's dma-buf. The tiling
> mode, caching mode and domains can not be changed for this kind of gem
> object.
> 3) change dma-buf related information to be more generic. So other vendor can
> use the same interface.
> 
> v1->v2:
> 1) create a management fd for dma-buf operations.
> 2) alloc gem object's backing storage in gem obj's get_pages() callback.
> 
> This patch set adds the dma-buf support for intel GVT-g.
> dma-buf is a uniform mechanism to share DMA buffers across different devices
> and sub-systems.
> dma-buf for intel GVT-g is mainly used to share the vgpu's framebuffer to other
> users or sub-systems so they can use the dma-buf to show the desktop of a vm
> which uses intel vgpu.
> 
> The main idea is we create a gem object and set vgpu's framebuffer as the
> backing storage of this gem object. And associate this gem obj to a dma-buf
> object then export this dma-buf at the meantime generate a file descriptor for
> this dma-buf. Finally deliver this file descriptor to user space. And user can use
> this dma-buf fd to do render or other operations.
> User need to create a fd(for intel GVT-g dma-buf support it is a:dma-buf
> management fd) then user can use this fd to query the plane information or
> create a dma-buf. The life cycle of this fd is managed by GVT-g user do not need
> to care about that.
> 
> We have an example program on how to use the dma-buf. You can download
> the program to have a try. Good luck :) git repo:
> https://github.com/01org/igvtg-qemu branch:kvmgt_dmabuf_example
> 
> 
> Tina Zhang (1):
>   vfio: ABI for mdev display dma-buf operation
> 
>  include/uapi/linux/vfio.h | 30 ++++++++++++++++++++++++++++++
>  1 file changed, 30 insertions(+)
> 
> --
> 2.7.4
> 
> _______________________________________________
> intel-gvt-dev mailing list
> intel-gvt-dev at lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/intel-gvt-dev