Commit a92741e7 authored by Felix Kuehling's avatar Felix Kuehling Committed by Alex Deucher
Browse files

drm/amdgpu: Allow P2P access through XGMI 



If peer memory is accessible through XGMI, allow leaving it in VRAM
rather than forcing its migration to GTT on DMABuf attachment.

Signed-off-by: default avatarFelix Kuehling <felix.kuehling@amd.com>
Tested-by: default avatarHao (Claire) Zhou <hao.zhou@amd.com>
Reviewed-by: default avatarChristian König <christian.koenig@amd.com>
Signed-off-by: default avatarAlex Deucher <alexander.deucher@amd.com>
(cherry picked from commit 372c8d72)
parent 756c85e4

drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.c

+29 −1
Original line number Diff line number Diff line
@@ -43,6 +43,29 @@ 
#include <linux/dma-fence-array.h>

#include <linux/pci-p2pdma.h>



static const struct dma_buf_attach_ops amdgpu_dma_buf_attach_ops;



/**

 * dma_buf_attach_adev - Helper to get adev of an attachment

 *

 * @attach: attachment

 *

 * Returns:

 * A struct amdgpu_device * if the attaching device is an amdgpu device or

 * partition, NULL otherwise.

 */

static struct amdgpu_device *dma_buf_attach_adev(struct dma_buf_attachment *attach)

{

	if (attach->importer_ops == &amdgpu_dma_buf_attach_ops) {

		struct drm_gem_object *obj = attach->importer_priv;

		struct amdgpu_bo *bo = gem_to_amdgpu_bo(obj);



		return amdgpu_ttm_adev(bo->tbo.bdev);

	}



	return NULL;

}



/**

 * amdgpu_dma_buf_attach - &dma_buf_ops.attach implementation

 *
@@ -54,11 +77,13 @@ 
static int amdgpu_dma_buf_attach(struct dma_buf *dmabuf,

				 struct dma_buf_attachment *attach)

{

	struct amdgpu_device *attach_adev = dma_buf_attach_adev(attach);

	struct drm_gem_object *obj = dmabuf->priv;

	struct amdgpu_bo *bo = gem_to_amdgpu_bo(obj);

	struct amdgpu_device *adev = amdgpu_ttm_adev(bo->tbo.bdev);



	if (pci_p2pdma_distance(adev->pdev, attach->dev, false) < 0)

	if (!amdgpu_dmabuf_is_xgmi_accessible(attach_adev, bo) &&

	    pci_p2pdma_distance(adev->pdev, attach->dev, false) < 0)

		attach->peer2peer = false;



	amdgpu_vm_bo_update_shared(bo);
@@ -480,6 +505,9 @@ bool amdgpu_dmabuf_is_xgmi_accessible(struct amdgpu_device *adev, 
	struct drm_gem_object *obj = &bo->tbo.base;

	struct drm_gem_object *gobj;



	if (!adev)

		return false;



	if (obj->import_attach) {

		struct dma_buf *dma_buf = obj->import_attach->dmabuf;