drm: Add drm_gem_vram_fill_create_dumb() to create dumb buffers

The helper function drm_gem_vram_fill_create_dumb() implements most of
struct drm_driver.dumb_create() for GEM-VRAM buffer objects. It's not a
full implementation of the callback, as several driver-specific parameters
are still required.

v4:
	* cleanups from checkpatch.pl
v2:
	* documentation fixes

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: http://patchwork.freedesktop.org/patch/msgid/20190508082630.15116-5-tzimmermann@suse.de
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>

diff --git a/drivers/gpu/drm/drm_gem_vram_helper.c b/drivers/gpu/drm/drm_gem_vram_helper.c
index 2640283743360963b365e83149f2bbd682fe7267..aba073279ca23bd8ba908742ddbbe774e96bafcf 100644 (file)
--- a/drivers/gpu/drm/drm_gem_vram_helper.c
+++ b/drivers/gpu/drm/drm_gem_vram_helper.c
@@ -1,6 +1,7 @@
 // SPDX-License-Identifier: GPL-2.0-or-later
 
 #include <drm/drm_gem_vram_helper.h>
+#include <drm/drm_mode.h>
 #include <drm/ttm/ttm_page_alloc.h>
 
 /**
@@ -411,6 +412,67 @@ void drm_gem_vram_kunmap(struct drm_gem_vram_object *gbo)
 }
 EXPORT_SYMBOL(drm_gem_vram_kunmap);
 
+/**
+ * drm_gem_vram_fill_create_dumb() - \
+       Helper for implementing &struct drm_driver.dumb_create
+ * @file:              the DRM file
+ * @dev:               the DRM device
+ * @bdev:              the TTM BO device managing the buffer object
+ * @pg_align:          the buffer's alignment in multiples of the page size
+ * @interruptible:     sleep interruptible if waiting for memory
+ * @args:              the arguments as provided to \
+                               &struct drm_driver.dumb_create
+ *
+ * This helper function fills &struct drm_mode_create_dumb, which is used
+ * by &struct drm_driver.dumb_create. Implementations of this interface
+ * should forwards their arguments to this helper, plus the driver-specific
+ * parameters.
+ *
+ * Returns:
+ * 0 on success, or
+ * a negative error code otherwise.
+ */
+int drm_gem_vram_fill_create_dumb(struct drm_file *file,
+                                 struct drm_device *dev,
+                                 struct ttm_bo_device *bdev,
+                                 unsigned long pg_align,
+                                 bool interruptible,
+                                 struct drm_mode_create_dumb *args)
+{
+       size_t pitch, size;
+       struct drm_gem_vram_object *gbo;
+       int ret;
+       u32 handle;
+
+       pitch = args->width * ((args->bpp + 7) / 8);
+       size = pitch * args->height;
+
+       size = roundup(size, PAGE_SIZE);
+       if (!size)
+               return -EINVAL;
+
+       gbo = drm_gem_vram_create(dev, bdev, size, pg_align, interruptible);
+       if (IS_ERR(gbo))
+               return PTR_ERR(gbo);
+
+       ret = drm_gem_handle_create(file, &gbo->gem, &handle);
+       if (ret)
+               goto err_drm_gem_object_put_unlocked;
+
+       drm_gem_object_put_unlocked(&gbo->gem);
+
+       args->pitch = pitch;
+       args->size = size;
+       args->handle = handle;
+
+       return 0;
+
+err_drm_gem_object_put_unlocked:
+       drm_gem_object_put_unlocked(&gbo->gem);
+       return ret;
+}
+EXPORT_SYMBOL(drm_gem_vram_fill_create_dumb);
+
 /*
  * Helpers for struct ttm_bo_driver
  */

diff --git a/include/drm/drm_gem_vram_helper.h b/include/drm/drm_gem_vram_helper.h
index b87cb2e9d9dace5b800bed3a1de28000e5e3e6da..8e54f721c9f8d27f84dcb6d81a3b3999285dead5 100644 (file)
--- a/include/drm/drm_gem_vram_helper.h
+++ b/include/drm/drm_gem_vram_helper.h
@@ -8,6 +8,7 @@
 #include <drm/ttm/ttm_placement.h>
 #include <linux/kernel.h> /* for container_of() */
 
+struct drm_mode_create_dumb;
 struct filp;
 
 #define DRM_GEM_VRAM_PL_FLAG_VRAM      TTM_PL_FLAG_VRAM
@@ -89,6 +90,13 @@ void drm_gem_vram_kunmap_at(struct drm_gem_vram_object *gbo,
                            struct ttm_bo_kmap_obj *kmap);
 void drm_gem_vram_kunmap(struct drm_gem_vram_object *gbo);
 
+int drm_gem_vram_fill_create_dumb(struct drm_file *file,
+                                 struct drm_device *dev,
+                                 struct ttm_bo_device *bdev,
+                                 unsigned long pg_align,
+                                 bool interruptible,
+                                 struct drm_mode_create_dumb *args);
+
 /*
  * Helpers for struct ttm_bo_driver
  */