drm/msm: 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 msm functions are being removed. The file_operations
structure fops is now being created by the helper macro
DEFINE_DRM_GEM_FOPS().

v2:
	* rebase onto latest upstream
	* remove declaration of msm_gem_mmap_obj() from msm_fbdev.c

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://lore.kernel.org/r/20210706084753.8194-1-tzimmermann@suse.de
[squash in missing VM_DONTEXPAND flag]
Signed-off-by: Rob Clark <robdclark@chromium.org>

drivers/gpu/drm/msm/msm_drv.c

@@ -1030,17 +1030,7 @@ static const struct drm_ioctl_desc msm_ioctls[] = {
 	DRM_IOCTL_DEF_DRV(MSM_SUBMITQUEUE_QUERY, msm_ioctl_submitqueue_query, DRM_RENDER_ALLOW),
 };
 
-static const struct file_operations fops = {
-	.owner              = THIS_MODULE,
-	.open               = drm_open,
-	.release            = drm_release,
-	.unlocked_ioctl     = drm_ioctl,
-	.compat_ioctl       = drm_compat_ioctl,
-	.poll               = drm_poll,
-	.read               = drm_read,
-	.llseek             = no_llseek,
-	.mmap               = msm_gem_mmap,
-};
+DEFINE_DRM_GEM_FOPS(fops);
 
 static const struct drm_driver msm_driver = {
 	.driver_features    = DRIVER_GEM |
@@ -1060,7 +1050,7 @@ static const struct drm_driver msm_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 = msm_gem_prime_import_sg_table,
-	.gem_prime_mmap     = msm_gem_prime_mmap,
+	.gem_prime_mmap     = drm_gem_prime_mmap,
 #ifdef CONFIG_DEBUG_FS
 	.debugfs_init       = msm_debugfs_init,
 #endif

drivers/gpu/drm/msm/msm_drv.h

@@ -309,7 +309,6 @@ void msm_gem_shrinker_cleanup(struct drm_device *dev);
 struct sg_table *msm_gem_prime_get_sg_table(struct drm_gem_object *obj);
 int msm_gem_prime_vmap(struct drm_gem_object *obj, struct dma_buf_map *map);
 void msm_gem_prime_vunmap(struct drm_gem_object *obj, struct dma_buf_map *map);
-int msm_gem_prime_mmap(struct drm_gem_object *obj, struct vm_area_struct *vma);
 struct drm_gem_object *msm_gem_prime_import_sg_table(struct drm_device *dev,
 		struct dma_buf_attachment *attach, struct sg_table *sg);
 int msm_gem_prime_pin(struct drm_gem_object *obj);

drivers/gpu/drm/msm/msm_fbdev.c

@@ -8,13 +8,12 @@
 #include <drm/drm_crtc.h>
 #include <drm/drm_fb_helper.h>
 #include <drm/drm_fourcc.h>
+#include <drm/drm_prime.h>
 
 #include "msm_drv.h"
 #include "msm_gem.h"
 #include "msm_kms.h"
 
-extern int msm_gem_mmap_obj(struct drm_gem_object *obj,
-					struct vm_area_struct *vma);
 static int msm_fbdev_mmap(struct fb_info *info, struct vm_area_struct *vma);
 
 /*
@@ -48,15 +47,8 @@ static int msm_fbdev_mmap(struct fb_info *info, struct vm_area_struct *vma)
 	struct drm_fb_helper *helper = (struct drm_fb_helper *)info->par;
 	struct msm_fbdev *fbdev = to_msm_fbdev(helper);
 	struct drm_gem_object *bo = msm_framebuffer_bo(fbdev->fb, 0);
-	int ret = 0;
 
-	ret = drm_gem_mmap_obj(bo, bo->size, vma);
-	if (ret) {
-		pr_err("%s:drm_gem_mmap_obj fail\n", __func__);
-		return ret;
-	}
-
-	return msm_gem_mmap_obj(bo, vma);
+	return drm_gem_prime_mmap(bo, vma);
 }
 
 static int msm_fbdev_create(struct drm_fb_helper *helper,

drivers/gpu/drm/msm/msm_gem.c

@@ -217,31 +217,6 @@ static pgprot_t msm_gem_pgprot(struct msm_gem_object *msm_obj, pgprot_t prot)
 	return prot;
 }
 
-int msm_gem_mmap_obj(struct drm_gem_object *obj,
-		struct vm_area_struct *vma)
-{
-	struct msm_gem_object *msm_obj = to_msm_bo(obj);
-
-	vma->vm_flags &= ~VM_PFNMAP;
-	vma->vm_flags |= VM_MIXEDMAP;
-	vma->vm_page_prot = msm_gem_pgprot(msm_obj, vm_get_page_prot(vma->vm_flags));
-
-	return 0;
-}
-
-int msm_gem_mmap(struct file *filp, struct vm_area_struct *vma)
-{
-	int ret;
-
-	ret = drm_gem_mmap(filp, vma);
-	if (ret) {
-		DBG("mmap failed: %d", ret);
-		return ret;
-	}
-
-	return msm_gem_mmap_obj(vma->vm_private_data, vma);
-}
-
 static vm_fault_t msm_gem_fault(struct vm_fault *vmf)
 {
 	struct vm_area_struct *vma = vmf->vma;
@@ -1077,6 +1052,17 @@ void msm_gem_free_object(struct drm_gem_object *obj)
 	kfree(msm_obj);
 }
 
+static int msm_gem_object_mmap(struct drm_gem_object *obj, struct vm_area_struct *vma)
+{
+	struct msm_gem_object *msm_obj = to_msm_bo(obj);
+
+	vma->vm_flags &= ~VM_PFNMAP;
+	vma->vm_flags |= VM_MIXEDMAP | VM_DONTEXPAND;
+	vma->vm_page_prot = msm_gem_pgprot(msm_obj, vm_get_page_prot(vma->vm_flags));
+
+	return 0;
+}
+
 /* convenience method to construct a GEM buffer object, and userspace handle */
 int msm_gem_new_handle(struct drm_device *dev, struct drm_file *file,
 		uint32_t size, uint32_t flags, uint32_t *handle,
@@ -1114,6 +1100,7 @@ static const struct drm_gem_object_funcs msm_gem_object_funcs = {
 	.get_sg_table = msm_gem_prime_get_sg_table,
 	.vmap = msm_gem_prime_vmap,
 	.vunmap = msm_gem_prime_vunmap,
+	.mmap = msm_gem_object_mmap,
 	.vm_ops = &vm_ops,
 };
 

drivers/gpu/drm/msm/msm_gem.h

@@ -106,9 +106,6 @@ struct msm_gem_object {
 };
 #define to_msm_bo(x) container_of(x, struct msm_gem_object, base)
 
-int msm_gem_mmap_obj(struct drm_gem_object *obj,
-			struct vm_area_struct *vma);
-int msm_gem_mmap(struct file *filp, struct vm_area_struct *vma);
 uint64_t msm_gem_mmap_offset(struct drm_gem_object *obj);
 int msm_gem_get_iova(struct drm_gem_object *obj,
 		struct msm_gem_address_space *aspace, uint64_t *iova);

drivers/gpu/drm/msm/msm_gem_prime.c

@@ -39,17 +39,6 @@ void msm_gem_prime_vunmap(struct drm_gem_object *obj, struct dma_buf_map *map)
 	msm_gem_put_vaddr(obj);
 }
 
-int msm_gem_prime_mmap(struct drm_gem_object *obj, struct vm_area_struct *vma)
-{
-	int ret;
-
-	ret = drm_gem_mmap_obj(obj, obj->size, vma);
-	if (ret < 0)
-		return ret;
-
-	return msm_gem_mmap_obj(vma->vm_private_data, vma);
-}
-
 struct drm_gem_object *msm_gem_prime_import_sg_table(struct drm_device *dev,
 		struct dma_buf_attachment *attach, struct sg_table *sg)
 {