Commit 3153c648 authored by Thomas Zimmermann's avatar Thomas Zimmermann
Browse files

drm/xen: Implement mmap as GEM object function 



Moving the driver-specific mmap code into a GEM object function allows
for using DRM helpers for various mmap callbacks.

The respective xen functions are being removed. The file_operations
structure fops is now being created by the helper macro
DEFINE_DRM_GEM_FOPS().

Signed-off-by: default avatarThomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: default avatarOleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211108102846.309-3-tzimmermann@suse.de
parent 790f27e0

drivers/gpu/drm/xen/xen_drm_front.c

+2 −14
Original line number Diff line number Diff line
@@ -469,19 +469,7 @@ static void xen_drm_drv_release(struct drm_device *dev) 
	kfree(drm_info);

}



static const struct file_operations xen_drm_dev_fops = {

	.owner          = THIS_MODULE,

	.open           = drm_open,

	.release        = drm_release,

	.unlocked_ioctl = drm_ioctl,

#ifdef CONFIG_COMPAT

	.compat_ioctl   = drm_compat_ioctl,

#endif

	.poll           = drm_poll,

	.read           = drm_read,

	.llseek         = no_llseek,

	.mmap           = xen_drm_front_gem_mmap,

};

DEFINE_DRM_GEM_FOPS(xen_drm_dev_fops);



static const struct drm_driver xen_drm_driver = {

	.driver_features           = DRIVER_GEM | DRIVER_MODESET | DRIVER_ATOMIC,
@@ -489,7 +477,7 @@ static const struct drm_driver xen_drm_driver = { 
	.prime_handle_to_fd        = drm_gem_prime_handle_to_fd,

	.prime_fd_to_handle        = drm_gem_prime_fd_to_handle,

	.gem_prime_import_sg_table = xen_drm_front_gem_import_sg_table,

	.gem_prime_mmap            = xen_drm_front_gem_prime_mmap,

	.gem_prime_mmap            = drm_gem_prime_mmap,

	.dumb_create               = xen_drm_drv_dumb_create,

	.fops                      = &xen_drm_dev_fops,

	.name                      = "xendrm-du",

drivers/gpu/drm/xen/xen_drm_front_gem.c

+42 −66
Original line number Diff line number Diff line
@@ -57,6 +57,47 @@ static void gem_free_pages_array(struct xen_gem_object *xen_obj) 
	xen_obj->pages = NULL;

}



static int xen_drm_front_gem_object_mmap(struct drm_gem_object *gem_obj,

					 struct vm_area_struct *vma)

{

	struct xen_gem_object *xen_obj = to_xen_gem_obj(gem_obj);

	int ret;



	vma->vm_ops = gem_obj->funcs->vm_ops;



	/*

	 * Clear the VM_PFNMAP flag that was set by drm_gem_mmap(), and set the

	 * vm_pgoff (used as a fake buffer offset by DRM) to 0 as we want to map

	 * the whole buffer.

	 */

	vma->vm_flags &= ~VM_PFNMAP;

	vma->vm_flags |= VM_MIXEDMAP;

	vma->vm_pgoff = 0;



	/*

	 * According to Xen on ARM ABI (xen/include/public/arch-arm.h):

	 * all memory which is shared with other entities in the system

	 * (including the hypervisor and other guests) must reside in memory

	 * which is mapped as Normal Inner Write-Back Outer Write-Back

	 * Inner-Shareable.

	 */

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



	/*

	 * vm_operations_struct.fault handler will be called if CPU access

	 * to VM is here. For GPUs this isn't the case, because CPU  doesn't

	 * touch the memory. Insert pages now, so both CPU and GPU are happy.

	 *

	 * FIXME: as we insert all the pages now then no .fault handler must

	 * be called, so don't provide one

	 */

	ret = vm_map_pages(vma, xen_obj->pages, xen_obj->num_pages);

	if (ret < 0)

		DRM_ERROR("Failed to map pages into vma: %d\n", ret);



	return ret;

}



static const struct vm_operations_struct xen_drm_drv_vm_ops = {

	.open           = drm_gem_vm_open,

	.close          = drm_gem_vm_close,
@@ -67,6 +108,7 @@ static const struct drm_gem_object_funcs xen_drm_front_gem_object_funcs = { 
	.get_sg_table = xen_drm_front_gem_get_sg_table,

	.vmap = xen_drm_front_gem_prime_vmap,

	.vunmap = xen_drm_front_gem_prime_vunmap,

	.mmap = xen_drm_front_gem_object_mmap,

	.vm_ops = &xen_drm_drv_vm_ops,

};
@@ -238,58 +280,6 @@ xen_drm_front_gem_import_sg_table(struct drm_device *dev, 
	return &xen_obj->base;

}



static int gem_mmap_obj(struct xen_gem_object *xen_obj,

			struct vm_area_struct *vma)

{

	int ret;



	/*

	 * clear the VM_PFNMAP flag that was set by drm_gem_mmap(), and set the

	 * vm_pgoff (used as a fake buffer offset by DRM) to 0 as we want to map

	 * the whole buffer.

	 */

	vma->vm_flags &= ~VM_PFNMAP;

	vma->vm_flags |= VM_MIXEDMAP;

	vma->vm_pgoff = 0;

	/*

	 * According to Xen on ARM ABI (xen/include/public/arch-arm.h):

	 * all memory which is shared with other entities in the system

	 * (including the hypervisor and other guests) must reside in memory

	 * which is mapped as Normal Inner Write-Back Outer Write-Back

	 * Inner-Shareable.

	 */

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



	/*

	 * vm_operations_struct.fault handler will be called if CPU access

	 * to VM is here. For GPUs this isn't the case, because CPU

	 * doesn't touch the memory. Insert pages now, so both CPU and GPU are

	 * happy.

	 * FIXME: as we insert all the pages now then no .fault handler must

	 * be called, so don't provide one

	 */

	ret = vm_map_pages(vma, xen_obj->pages, xen_obj->num_pages);

	if (ret < 0)

		DRM_ERROR("Failed to map pages into vma: %d\n", ret);



	return ret;

}



int xen_drm_front_gem_mmap(struct file *filp, struct vm_area_struct *vma)

{

	struct xen_gem_object *xen_obj;

	struct drm_gem_object *gem_obj;

	int ret;



	ret = drm_gem_mmap(filp, vma);

	if (ret < 0)

		return ret;



	gem_obj = vma->vm_private_data;

	xen_obj = to_xen_gem_obj(gem_obj);

	return gem_mmap_obj(xen_obj, vma);

}



int xen_drm_front_gem_prime_vmap(struct drm_gem_object *gem_obj, struct dma_buf_map *map)

{

	struct xen_gem_object *xen_obj = to_xen_gem_obj(gem_obj);
@@ -313,17 +303,3 @@ void xen_drm_front_gem_prime_vunmap(struct drm_gem_object *gem_obj, 
{

	vunmap(map->vaddr);

}
 


int xen_drm_front_gem_prime_mmap(struct drm_gem_object *gem_obj,

				 struct vm_area_struct *vma)

{

	struct xen_gem_object *xen_obj;

	int ret;



	ret = drm_gem_mmap_obj(gem_obj, gem_obj->size, vma);

	if (ret < 0)

		return ret;



	xen_obj = to_xen_gem_obj(gem_obj);

	return gem_mmap_obj(xen_obj, vma);

}

drivers/gpu/drm/xen/xen_drm_front_gem.h

+0 −7
Original line number Diff line number Diff line
@@ -15,9 +15,7 @@ struct dma_buf_attachment; 
struct dma_buf_map;

struct drm_device;

struct drm_gem_object;

struct file;

struct sg_table;

struct vm_area_struct;



struct drm_gem_object *xen_drm_front_gem_create(struct drm_device *dev,

						size_t size);
@@ -33,15 +31,10 @@ struct page **xen_drm_front_gem_get_pages(struct drm_gem_object *obj); 


void xen_drm_front_gem_free_object_unlocked(struct drm_gem_object *gem_obj);



int xen_drm_front_gem_mmap(struct file *filp, struct vm_area_struct *vma);



int xen_drm_front_gem_prime_vmap(struct drm_gem_object *gem_obj,

				 struct dma_buf_map *map);



void xen_drm_front_gem_prime_vunmap(struct drm_gem_object *gem_obj,

				    struct dma_buf_map *map);



int xen_drm_front_gem_prime_mmap(struct drm_gem_object *gem_obj,

				 struct vm_area_struct *vma);



#endif /* __XEN_DRM_FRONT_GEM_H */