drm/vmwgfx: Use the common gem mmap instead of the custom code

Before vmwgfx supported gem it needed to implement the entire mmap logic
explicitly. With GEM support that's not needed and the generic code
can be used by simply setting the vm_ops to vmwgfx specific ones on the
gem object itself.

Removes a lot of code from vmwgfx without any functional difference.

Signed-off-by: Zack Rusin <[e-mail]>
Reviewed-by: Thomas Zimmermann <[e-mail]>
Reviewed-by: Martin Krastev <[e-mail]>
Reviewed-by: Maaz Mombasawala <[e-mail]>
Link: https://patchwork.freedesktop.org/patch/msgid/[e-mail]

drivers/gpu/drm/vmwgfx/Makefile

···
 # SPDX-License-Identifier: GPL-2.0
 vmwgfx-y := vmwgfx_execbuf.o vmwgfx_gmr.o vmwgfx_kms.o vmwgfx_drv.o \
 	    vmwgfx_ioctl.o vmwgfx_resource.o vmwgfx_ttm_buffer.o \
-	    vmwgfx_cmd.o vmwgfx_irq.o vmwgfx_ldu.o vmwgfx_ttm_glue.o \
+	    vmwgfx_cmd.o vmwgfx_irq.o vmwgfx_ldu.o \
 	    vmwgfx_overlay.o vmwgfx_gmrid_manager.o vmwgfx_fence.o \
 	    vmwgfx_bo.o vmwgfx_scrn.o vmwgfx_context.o \
 	    vmwgfx_surface.o vmwgfx_prime.o vmwgfx_mob.o vmwgfx_shader.o \

drivers/gpu/drm/vmwgfx/vmwgfx_drv.c

···
 	.open = drm_open,
 	.release = drm_release,
 	.unlocked_ioctl = vmw_unlocked_ioctl,
-	.mmap = vmw_mmap,
+	.mmap = drm_gem_mmap,
 	.poll = drm_poll,
 	.read = drm_read,
 #if defined(CONFIG_COMPAT)

drivers/gpu/drm/vmwgfx/vmwgfx_drv.h

···
 }
 
 /**
- * TTM glue - vmwgfx_ttm_glue.c
- */
-
-extern int vmw_mmap(struct file *filp, struct vm_area_struct *vma);
-
-/**
  * TTM buffer object driver - vmwgfx_ttm_buffer.c
  */
 

drivers/gpu/drm/vmwgfx/vmwgfx_gem.c

···
 	return drm_prime_pages_to_sg(obj->dev, vmw_tt->dma_ttm.pages, vmw_tt->dma_ttm.num_pages);
 }
 
+static const struct vm_operations_struct vmw_vm_ops = {
+	.pfn_mkwrite = vmw_bo_vm_mkwrite,
+	.page_mkwrite = vmw_bo_vm_mkwrite,
+	.fault = vmw_bo_vm_fault,
+	.open = ttm_bo_vm_open,
+	.close = ttm_bo_vm_close,
+};
 
 static const struct drm_gem_object_funcs vmw_gem_object_funcs = {
 	.free = vmw_gem_object_free,
···
 	.vmap = drm_gem_ttm_vmap,
 	.vunmap = drm_gem_ttm_vunmap,
 	.mmap = drm_gem_ttm_mmap,
+	.vm_ops = &vmw_vm_ops,
 };
 
 /**

drivers/gpu/drm/vmwgfx/vmwgfx_ttm_glue.c

···
-// SPDX-License-Identifier: GPL-2.0 OR MIT
-/**************************************************************************
- *
- * Copyright 2009-2011 VMware, Inc., Palo Alto, CA., USA
- *
- * Permission is hereby granted, free of charge, to any person obtaining a
- * copy of this software and associated documentation files (the
- * "Software"), to deal in the Software without restriction, including
- * without limitation the rights to use, copy, modify, merge, publish,
- * distribute, sub license, and/or sell copies of the Software, and to
- * permit persons to whom the Software is furnished to do so, subject to
- * the following conditions:
- *
- * The above copyright notice and this permission notice (including the
- * next paragraph) shall be included in all copies or substantial portions
- * of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
- * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
- * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
- * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
- * USE OR OTHER DEALINGS IN THE SOFTWARE.
- *
- **************************************************************************/
-
-#include "vmwgfx_drv.h"
-
-static int vmw_bo_vm_lookup(struct ttm_device *bdev,
-				   struct drm_file *filp,
-				   unsigned long offset,
-				   unsigned long pages,
-				   struct ttm_buffer_object **p_bo)
-{
-	struct vmw_private *dev_priv = container_of(bdev, struct vmw_private, bdev);
-	struct drm_device *drm = &dev_priv->drm;
-	struct drm_vma_offset_node *node;
-	int ret;
-
-	*p_bo = NULL;
-
-	drm_vma_offset_lock_lookup(bdev->vma_manager);
-
-	node = drm_vma_offset_lookup_locked(bdev->vma_manager, offset, pages);
-	if (likely(node)) {
-		*p_bo = container_of(node, struct ttm_buffer_object,
-				  base.vma_node);
-		*p_bo = ttm_bo_get_unless_zero(*p_bo);
-	}
-
-	drm_vma_offset_unlock_lookup(bdev->vma_manager);
-
-	if (!*p_bo) {
-		drm_err(drm, "Could not find buffer object to map\n");
-		return -EINVAL;
-	}
-
-	if (!drm_vma_node_is_allowed(node, filp)) {
-		ret = -EACCES;
-		goto out_no_access;
-	}
-
-	return 0;
-out_no_access:
-	ttm_bo_put(*p_bo);
-	return ret;
-}
-
-int vmw_mmap(struct file *filp, struct vm_area_struct *vma)
-{
-	static const struct vm_operations_struct vmw_vm_ops = {
-		.pfn_mkwrite = vmw_bo_vm_mkwrite,
-		.page_mkwrite = vmw_bo_vm_mkwrite,
-		.fault = vmw_bo_vm_fault,
-		.open = ttm_bo_vm_open,
-		.close = ttm_bo_vm_close,
-	};
-	struct drm_file *file_priv = filp->private_data;
-	struct vmw_private *dev_priv = vmw_priv(file_priv->minor->dev);
-	struct ttm_device *bdev = &dev_priv->bdev;
-	struct ttm_buffer_object *bo;
-	int ret;
-
-	if (unlikely(vma->vm_pgoff < DRM_FILE_PAGE_OFFSET_START))
-		return -EINVAL;
-
-	ret = vmw_bo_vm_lookup(bdev, file_priv, vma->vm_pgoff, vma_pages(vma), &bo);
-	if (unlikely(ret != 0))
-		return ret;
-
-	ret = ttm_bo_mmap_obj(vma, bo);
-	if (unlikely(ret != 0))
-		goto out_unref;
-
-	vma->vm_ops = &vmw_vm_ops;
-
-	/* Use VM_PFNMAP rather than VM_MIXEDMAP if not a COW mapping */
-	if (!is_cow_mapping(vma->vm_flags))
-		vma->vm_flags = (vma->vm_flags & ~VM_MIXEDMAP) | VM_PFNMAP;
-
-	ttm_bo_put(bo); /* release extra ref taken by ttm_bo_mmap_obj() */
-
-	return 0;
-
-out_unref:
-	ttm_bo_put(bo);
-	return ret;
-}
-