Commit 1cad6292 authored by Gerd Hoffmann's avatar Gerd Hoffmann
Browse files

drm/shmem: add support for per object caching flags. 



Add map_cached bool to drm_gem_shmem_object, to request cached mappings
on a per-object base.  Check the flag before adding writecombine to
pgprot bits.

Cc: stable@vger.kernel.org
Signed-off-by: default avatarGerd Hoffmann <kraxel@redhat.com>
Reviewed-by: default avatarGurchetan Singh <gurchetansingh@chromium.org>
Tested-by: default avatarGuillaume Gardet <Guillaume.Gardet@arm.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20200226154752.24328-2-kraxel@redhat.com
parent d1f37226

drivers/gpu/drm/drm_gem_shmem_helper.c

+11 −4
Original line number Diff line number Diff line
@@ -254,11 +254,16 @@ static void *drm_gem_shmem_vmap_locked(struct drm_gem_shmem_object *shmem) 
	if (ret)

		goto err_zero_use;



	if (obj->import_attach)

	if (obj->import_attach) {

		shmem->vaddr = dma_buf_vmap(obj->import_attach->dmabuf);

	else

	} else {

		pgprot_t prot = PAGE_KERNEL;



		if (!shmem->map_cached)

			prot = pgprot_writecombine(prot);

		shmem->vaddr = vmap(shmem->pages, obj->size >> PAGE_SHIFT,

				    VM_MAP, pgprot_writecombine(PAGE_KERNEL));

				    VM_MAP, prot);

	}



	if (!shmem->vaddr) {

		DRM_DEBUG_KMS("Failed to vmap pages\n");
@@ -540,7 +545,9 @@ int drm_gem_shmem_mmap(struct drm_gem_object *obj, struct vm_area_struct *vma) 
	}



	vma->vm_flags |= VM_MIXEDMAP | VM_DONTEXPAND;

	vma->vm_page_prot = pgprot_writecombine(vm_get_page_prot(vma->vm_flags));

	vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);

	if (!shmem->map_cached)

		vma->vm_page_prot = pgprot_writecombine(vma->vm_page_prot);

	vma->vm_page_prot = pgprot_decrypted(vma->vm_page_prot);

	vma->vm_ops = &drm_gem_shmem_vm_ops;

include/drm/drm_gem_shmem_helper.h

+5 −0
Original line number Diff line number Diff line
@@ -96,6 +96,11 @@ struct drm_gem_shmem_object { 
	 * The address are un-mapped when the count reaches zero.

	 */

	unsigned int vmap_use_count;



	/**

	 * @map_cached: map object cached (instead of using writecombine).

	 */

	bool map_cached;

};



#define to_drm_gem_shmem_obj(obj) \

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