drm/exynos: merge exynos_drm_buf.c to exynos_drm_gem.c

The struct exynos_drm_gem_obj can have fields of the struct
exynos_drm_gem_buf then don't need to use exynos_drm_buf.c file.

Signed-off-by: Joonyoung Shim <jy0922.shim@samsung.com>
Signed-off-by: Inki Dae <inki.dae@samsung.com>

9 files changed, 180 insertions, 334 deletions

diff --git a/drivers/gpu/drm/exynos/Makefile b/drivers/gpu/drm/exynos/Makefile
index 6916b22a7382..02aecfed6354 100644
--- a/drivers/gpu/drm/exynos/Makefile
+++ b/drivers/gpu/drm/exynos/Makefile
@@ -4,8 +4,8 @@
 
 ccflags-y := -Iinclude/drm -Idrivers/gpu/drm/exynos
 exynosdrm-y := exynos_drm_drv.o exynos_drm_crtc.o exynos_drm_fbdev.o \
-		exynos_drm_fb.o exynos_drm_buf.o exynos_drm_gem.o \
-		exynos_drm_core.o exynos_drm_plane.o
+		exynos_drm_fb.o exynos_drm_gem.o exynos_drm_core.o \
+		exynos_drm_plane.o
 
 exynosdrm-$(CONFIG_DRM_EXYNOS_IOMMU) += exynos_drm_iommu.o
 exynosdrm-$(CONFIG_DRM_EXYNOS_FIMD)	+= exynos_drm_fimd.o
diff --git a/drivers/gpu/drm/exynos/exynos_drm_buf.c b/drivers/gpu/drm/exynos/exynos_drm_buf.c
deleted file mode 100644
index 9260dfb3b7e5..000000000000
--- a/drivers/gpu/drm/exynos/exynos_drm_buf.c
+++ /dev/null
@@ -1,170 +0,0 @@
-/* exynos_drm_buf.c
- *
- * Copyright (c) 2011 Samsung Electronics Co., Ltd.
- * Author: Inki Dae <inki.dae@samsung.com>
- *
- * This program is free software; you can redistribute  it and/or modify it
- * under  the terms of  the GNU General  Public License as published by the
- * Free Software Foundation;  either version 2 of the  License, or (at your
- * option) any later version.
- */
-
-#include <drm/drmP.h>
-#include <drm/exynos_drm.h>
-
-#include "exynos_drm_drv.h"
-#include "exynos_drm_gem.h"
-#include "exynos_drm_buf.h"
-#include "exynos_drm_iommu.h"
-
-static int lowlevel_buffer_allocate(struct drm_device *dev,
-		unsigned int flags, struct exynos_drm_gem_buf *buf)
-{
-	int ret = 0;
-	enum dma_attr attr;
-	unsigned int nr_pages;
-
-	if (buf->dma_addr) {
-		DRM_DEBUG_KMS("already allocated.\n");
-		return 0;
-	}
-
-	init_dma_attrs(&buf->dma_attrs);
-
-	/*
-	 * if EXYNOS_BO_CONTIG, fully physically contiguous memory
-	 * region will be allocated else physically contiguous
-	 * as possible.
-	 */
-	if (!(flags & EXYNOS_BO_NONCONTIG))
-		dma_set_attr(DMA_ATTR_FORCE_CONTIGUOUS, &buf->dma_attrs);
-
-	/*
-	 * if EXYNOS_BO_WC or EXYNOS_BO_NONCACHABLE, writecombine mapping
-	 * else cachable mapping.
-	 */
-	if (flags & EXYNOS_BO_WC || !(flags & EXYNOS_BO_CACHABLE))
-		attr = DMA_ATTR_WRITE_COMBINE;
-	else
-		attr = DMA_ATTR_NON_CONSISTENT;
-
-	dma_set_attr(attr, &buf->dma_attrs);
-	dma_set_attr(DMA_ATTR_NO_KERNEL_MAPPING, &buf->dma_attrs);
-
-	nr_pages = buf->size >> PAGE_SHIFT;
-
-	if (!is_drm_iommu_supported(dev)) {
-		dma_addr_t start_addr;
-		unsigned int i = 0;
-
-		buf->pages = drm_calloc_large(nr_pages, sizeof(struct page *));
-		if (!buf->pages) {
-			DRM_ERROR("failed to allocate pages.\n");
-			return -ENOMEM;
-		}
-
-		buf->cookie = dma_alloc_attrs(dev->dev,
-					buf->size,
-					&buf->dma_addr, GFP_KERNEL,
-					&buf->dma_attrs);
-		if (!buf->cookie) {
-			DRM_ERROR("failed to allocate buffer.\n");
-			ret = -ENOMEM;
-			goto err_free;
-		}
-
-		start_addr = buf->dma_addr;
-		while (i < nr_pages) {
-			buf->pages[i] = phys_to_page(start_addr);
-			start_addr += PAGE_SIZE;
-			i++;
-		}
-	} else {
-
-		buf->pages = dma_alloc_attrs(dev->dev, buf->size,
-					&buf->dma_addr, GFP_KERNEL,
-					&buf->dma_attrs);
-		if (!buf->pages) {
-			DRM_ERROR("failed to allocate buffer.\n");
-			return -ENOMEM;
-		}
-	}
-
-	DRM_DEBUG_KMS("dma_addr(0x%lx), size(0x%lx)\n",
-			(unsigned long)buf->dma_addr,
-			buf->size);
-
-	return ret;
-
-err_free:
-	if (!is_drm_iommu_supported(dev))
-		drm_free_large(buf->pages);
-
-	return ret;
-}
-
-static void lowlevel_buffer_deallocate(struct drm_device *dev,
-		unsigned int flags, struct exynos_drm_gem_buf *buf)
-{
-	if (!buf->dma_addr) {
-		DRM_DEBUG_KMS("dma_addr is invalid.\n");
-		return;
-	}
-
-	DRM_DEBUG_KMS("dma_addr(0x%lx), size(0x%lx)\n",
-			(unsigned long)buf->dma_addr,
-			buf->size);
-
-	if (!is_drm_iommu_supported(dev)) {
-		dma_free_attrs(dev->dev, buf->size, buf->cookie,
-				(dma_addr_t)buf->dma_addr, &buf->dma_attrs);
-		drm_free_large(buf->pages);
-	} else
-		dma_free_attrs(dev->dev, buf->size, buf->pages,
-				(dma_addr_t)buf->dma_addr, &buf->dma_attrs);
-
-	buf->dma_addr = (dma_addr_t)NULL;
-}
-
-struct exynos_drm_gem_buf *exynos_drm_init_buf(struct drm_device *dev,
-						unsigned int size)
-{
-	struct exynos_drm_gem_buf *buffer;
-
-	DRM_DEBUG_KMS("desired size = 0x%x\n", size);
-
-	buffer = kzalloc(sizeof(*buffer), GFP_KERNEL);
-	if (!buffer)
-		return NULL;
-
-	buffer->size = size;
-	return buffer;
-}
-
-void exynos_drm_fini_buf(struct drm_device *dev,
-				struct exynos_drm_gem_buf *buffer)
-{
-	kfree(buffer);
-	buffer = NULL;
-}
-
-int exynos_drm_alloc_buf(struct drm_device *dev,
-		struct exynos_drm_gem_buf *buf, unsigned int flags)
-{
-
-	/*
-	 * allocate memory region and set the memory information
-	 * to vaddr and dma_addr of a buffer object.
-	 */
-	if (lowlevel_buffer_allocate(dev, flags, buf) < 0)
-		return -ENOMEM;
-
-	return 0;
-}
-
-void exynos_drm_free_buf(struct drm_device *dev,
-		unsigned int flags, struct exynos_drm_gem_buf *buffer)
-{
-
-	lowlevel_buffer_deallocate(dev, flags, buffer);
-}
diff --git a/drivers/gpu/drm/exynos/exynos_drm_buf.h b/drivers/gpu/drm/exynos/exynos_drm_buf.h
deleted file mode 100644
index a6412f19673c..000000000000
--- a/drivers/gpu/drm/exynos/exynos_drm_buf.h
+++ /dev/null
@@ -1,33 +0,0 @@
-/* exynos_drm_buf.h
- *
- * Copyright (c) 2011 Samsung Electronics Co., Ltd.
- * Author: Inki Dae <inki.dae@samsung.com>
- *
- * This program is free software; you can redistribute  it and/or modify it
- * under  the terms of  the GNU General  Public License as published by the
- * Free Software Foundation;  either version 2 of the  License, or (at your
- * option) any later version.
- */
-
-#ifndef _EXYNOS_DRM_BUF_H_
-#define _EXYNOS_DRM_BUF_H_
-
-/* create and initialize buffer object. */
-struct exynos_drm_gem_buf *exynos_drm_init_buf(struct drm_device *dev,
-						unsigned int size);
-
-/* destroy buffer object. */
-void exynos_drm_fini_buf(struct drm_device *dev,
-				struct exynos_drm_gem_buf *buffer);
-
-/* allocate physical memory region and setup sgt. */
-int exynos_drm_alloc_buf(struct drm_device *dev,
-				struct exynos_drm_gem_buf *buf,
-				unsigned int flags);
-
-/* release physical memory region, and sgt. */
-void exynos_drm_free_buf(struct drm_device *dev,
-				unsigned int flags,
-				struct exynos_drm_gem_buf *buffer);
-
-#endif
diff --git a/drivers/gpu/drm/exynos/exynos_drm_fb.c b/drivers/gpu/drm/exynos/exynos_drm_fb.c
index 2b6320e6eae2..9738f4e0c6eb 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_fb.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_fb.c
@@ -238,22 +238,22 @@ err_free:
 	return ERR_PTR(ret);
 }
 
-struct exynos_drm_gem_buf *exynos_drm_fb_buffer(struct drm_framebuffer *fb,
-						int index)
+struct exynos_drm_gem_obj *exynos_drm_fb_gem_obj(struct drm_framebuffer *fb,
+						 int index)
 {
 	struct exynos_drm_fb *exynos_fb = to_exynos_fb(fb);
-	struct exynos_drm_gem_buf *buffer;
+	struct exynos_drm_gem_obj *obj;
 
 	if (index >= MAX_FB_BUFFER)
 		return NULL;
 
-	buffer = exynos_fb->exynos_gem_obj[index]->buffer;
-	if (!buffer)
+	obj = exynos_fb->exynos_gem_obj[index];
+	if (!obj)
 		return NULL;
 
-	DRM_DEBUG_KMS("dma_addr = 0x%lx\n", (unsigned long)buffer->dma_addr);
+	DRM_DEBUG_KMS("dma_addr = 0x%lx\n", (unsigned long)obj->dma_addr);
 
-	return buffer;
+	return obj;
 }
 
 static void exynos_drm_output_poll_changed(struct drm_device *dev)
diff --git a/drivers/gpu/drm/exynos/exynos_drm_fb.h b/drivers/gpu/drm/exynos/exynos_drm_fb.h
index 517471b37566..1c9e27c32cd1 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_fb.h
+++ b/drivers/gpu/drm/exynos/exynos_drm_fb.h
@@ -19,8 +19,8 @@ exynos_drm_framebuffer_init(struct drm_device *dev,
 			    struct drm_mode_fb_cmd2 *mode_cmd,
 			    struct drm_gem_object *obj);
 
-/* get memory information of a drm framebuffer */
-struct exynos_drm_gem_buf *exynos_drm_fb_buffer(struct drm_framebuffer *fb,
+/* get gem object of a drm framebuffer */
+struct exynos_drm_gem_obj *exynos_drm_fb_gem_obj(struct drm_framebuffer *fb,
 						 int index);
 
 void exynos_drm_mode_config_init(struct drm_device *dev);
diff --git a/drivers/gpu/drm/exynos/exynos_drm_fbdev.c b/drivers/gpu/drm/exynos/exynos_drm_fbdev.c
index dd64bc04ffbb..624595afbce0 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_fbdev.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_fbdev.c
@@ -40,8 +40,7 @@ static int exynos_drm_fb_mmap(struct fb_info *info,
 {
 	struct drm_fb_helper *helper = info->par;
 	struct exynos_drm_fbdev *exynos_fbd = to_exynos_fbdev(helper);
-	struct exynos_drm_gem_obj *exynos_gem_obj = exynos_fbd->exynos_gem_obj;
-	struct exynos_drm_gem_buf *buffer = exynos_gem_obj->buffer;
+	struct exynos_drm_gem_obj *obj = exynos_fbd->exynos_gem_obj;
 	unsigned long vm_size;
 	int ret;
 
@@ -49,11 +48,11 @@ static int exynos_drm_fb_mmap(struct fb_info *info,
 
 	vm_size = vma->vm_end - vma->vm_start;
 
-	if (vm_size > buffer->size)
+	if (vm_size > obj->size)
 		return -EINVAL;
 
-	ret = dma_mmap_attrs(helper->dev->dev, vma, buffer->pages,
-		buffer->dma_addr, buffer->size, &buffer->dma_attrs);
+	ret = dma_mmap_attrs(helper->dev->dev, vma, obj->pages, obj->dma_addr,
+			     obj->size, &obj->dma_attrs);
 	if (ret < 0) {
 		DRM_ERROR("failed to mmap.\n");
 		return ret;
@@ -80,7 +79,7 @@ static int exynos_drm_fbdev_update(struct drm_fb_helper *helper,
 				     struct drm_framebuffer *fb)
 {
 	struct fb_info *fbi = helper->fbdev;
-	struct exynos_drm_gem_buf *buffer;
+	struct exynos_drm_gem_obj *obj;
 	unsigned int size = fb->width * fb->height * (fb->bits_per_pixel >> 3);
 	unsigned int nr_pages;
 	unsigned long offset;
@@ -89,18 +88,17 @@ static int exynos_drm_fbdev_update(struct drm_fb_helper *helper,
 	drm_fb_helper_fill_var(fbi, helper, sizes->fb_width, sizes->fb_height);
 
 	/* RGB formats use only one buffer */
-	buffer = exynos_drm_fb_buffer(fb, 0);
-	if (!buffer) {
-		DRM_DEBUG_KMS("buffer is null.\n");
+	obj = exynos_drm_fb_gem_obj(fb, 0);
+	if (!obj) {
+		DRM_DEBUG_KMS("gem object is null.\n");
 		return -EFAULT;
 	}
 
-	nr_pages = buffer->size >> PAGE_SHIFT;
+	nr_pages = obj->size >> PAGE_SHIFT;
 
-	buffer->kvaddr = (void __iomem *) vmap(buffer->pages,
-			nr_pages, VM_MAP,
+	obj->kvaddr = (void __iomem *) vmap(obj->pages, nr_pages, VM_MAP,
 			pgprot_writecombine(PAGE_KERNEL));
-	if (!buffer->kvaddr) {
+	if (!obj->kvaddr) {
 		DRM_ERROR("failed to map pages to kernel space.\n");
 		return -EIO;
 	}
@@ -111,7 +109,7 @@ static int exynos_drm_fbdev_update(struct drm_fb_helper *helper,
 	offset = fbi->var.xoffset * (fb->bits_per_pixel >> 3);
 	offset += fbi->var.yoffset * fb->pitches[0];
 
-	fbi->screen_base = buffer->kvaddr + offset;
+	fbi->screen_base = obj->kvaddr + offset;
 	fbi->screen_size = size;
 	fbi->fix.smem_len = size;
 
@@ -290,8 +288,8 @@ static void exynos_drm_fbdev_destroy(struct drm_device *dev,
 	struct exynos_drm_gem_obj *exynos_gem_obj = exynos_fbd->exynos_gem_obj;
 	struct drm_framebuffer *fb;
 
-	if (exynos_gem_obj->buffer->kvaddr)
-		vunmap(exynos_gem_obj->buffer->kvaddr);
+	if (exynos_gem_obj->kvaddr)
+		vunmap(exynos_gem_obj->kvaddr);
 
 	/* release drm framebuffer and real buffer */
 	if (fb_helper->fb && fb_helper->fb->funcs) {
diff --git a/drivers/gpu/drm/exynos/exynos_drm_gem.c b/drivers/gpu/drm/exynos/exynos_drm_gem.c
index 768a632dfa2a..67461b77f040 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_gem.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_gem.c
@@ -18,9 +18,109 @@
 
 #include "exynos_drm_drv.h"
 #include "exynos_drm_gem.h"
-#include "exynos_drm_buf.h"
 #include "exynos_drm_iommu.h"
 
+static int exynos_drm_alloc_buf(struct exynos_drm_gem_obj *obj)
+{
+	struct drm_device *dev = obj->base.dev;
+	enum dma_attr attr;
+	unsigned int nr_pages;
+
+	if (obj->dma_addr) {
+		DRM_DEBUG_KMS("already allocated.\n");
+		return 0;
+	}
+
+	init_dma_attrs(&obj->dma_attrs);
+
+	/*
+	 * if EXYNOS_BO_CONTIG, fully physically contiguous memory
+	 * region will be allocated else physically contiguous
+	 * as possible.
+	 */
+	if (!(obj->flags & EXYNOS_BO_NONCONTIG))
+		dma_set_attr(DMA_ATTR_FORCE_CONTIGUOUS, &obj->dma_attrs);
+
+	/*
+	 * if EXYNOS_BO_WC or EXYNOS_BO_NONCACHABLE, writecombine mapping
+	 * else cachable mapping.
+	 */
+	if (obj->flags & EXYNOS_BO_WC || !(obj->flags & EXYNOS_BO_CACHABLE))
+		attr = DMA_ATTR_WRITE_COMBINE;
+	else
+		attr = DMA_ATTR_NON_CONSISTENT;
+
+	dma_set_attr(attr, &obj->dma_attrs);
+	dma_set_attr(DMA_ATTR_NO_KERNEL_MAPPING, &obj->dma_attrs);
+
+	nr_pages = obj->size >> PAGE_SHIFT;
+
+	if (!is_drm_iommu_supported(dev)) {
+		dma_addr_t start_addr;
+		unsigned int i = 0;
+
+		obj->pages = drm_calloc_large(nr_pages, sizeof(struct page *));
+		if (!obj->pages) {
+			DRM_ERROR("failed to allocate pages.\n");
+			return -ENOMEM;
+		}
+
+		obj->cookie = dma_alloc_attrs(dev->dev,
+					obj->size,
+					&obj->dma_addr, GFP_KERNEL,
+					&obj->dma_attrs);
+		if (!obj->cookie) {
+			DRM_ERROR("failed to allocate buffer.\n");
+			drm_free_large(obj->pages);
+			return -ENOMEM;
+		}
+
+		start_addr = obj->dma_addr;
+		while (i < nr_pages) {
+			obj->pages[i] = phys_to_page(start_addr);
+			start_addr += PAGE_SIZE;
+			i++;
+		}
+	} else {
+		obj->pages = dma_alloc_attrs(dev->dev, obj->size,
+					&obj->dma_addr, GFP_KERNEL,
+					&obj->dma_attrs);
+		if (!obj->pages) {
+			DRM_ERROR("failed to allocate buffer.\n");
+			return -ENOMEM;
+		}
+	}
+
+	DRM_DEBUG_KMS("dma_addr(0x%lx), size(0x%lx)\n",
+			(unsigned long)obj->dma_addr,
+			obj->size);
+
+	return 0;
+}
+
+static void exynos_drm_free_buf(struct exynos_drm_gem_obj *obj)
+{
+	struct drm_device *dev = obj->base.dev;
+
+	if (!obj->dma_addr) {
+		DRM_DEBUG_KMS("dma_addr is invalid.\n");
+		return;
+	}
+
+	DRM_DEBUG_KMS("dma_addr(0x%lx), size(0x%lx)\n",
+			(unsigned long)obj->dma_addr, obj->size);
+
+	if (!is_drm_iommu_supported(dev)) {
+		dma_free_attrs(dev->dev, obj->size, obj->cookie,
+				(dma_addr_t)obj->dma_addr, &obj->dma_attrs);
+		drm_free_large(obj->pages);
+	} else
+		dma_free_attrs(dev->dev, obj->size, obj->pages,
+				(dma_addr_t)obj->dma_addr, &obj->dma_attrs);
+
+	obj->dma_addr = (dma_addr_t)NULL;
+}
+
 static int exynos_drm_gem_handle_create(struct drm_gem_object *obj,
 					struct drm_file *file_priv,
 					unsigned int *handle)
@@ -45,11 +145,7 @@ static int exynos_drm_gem_handle_create(struct drm_gem_object *obj,
 
 void exynos_drm_gem_destroy(struct exynos_drm_gem_obj *exynos_gem_obj)
 {
-	struct drm_gem_object *obj;
-	struct exynos_drm_gem_buf *buf;
-
-	obj = &exynos_gem_obj->base;
-	buf = exynos_gem_obj->buffer;
+	struct drm_gem_object *obj = &exynos_gem_obj->base;
 
 	DRM_DEBUG_KMS("handle count = %d\n", obj->handle_count);
 
@@ -62,12 +158,9 @@ void exynos_drm_gem_destroy(struct exynos_drm_gem_obj *exynos_gem_obj)
 	if (obj->import_attach)
 		goto out;
 
-	exynos_drm_free_buf(obj->dev, exynos_gem_obj->flags, buf);
+	exynos_drm_free_buf(exynos_gem_obj);
 
 out:
-	exynos_drm_fini_buf(obj->dev, buf);
-	exynos_gem_obj->buffer = NULL;
-
 	drm_gem_free_mmap_offset(obj);
 
 	/* release file pointer to gem object. */
@@ -94,7 +187,7 @@ unsigned long exynos_drm_gem_get_size(struct drm_device *dev,
 
 	drm_gem_object_unreference_unlocked(obj);
 
-	return exynos_gem_obj->buffer->size;
+	return exynos_gem_obj->size;
 }
 
 
@@ -129,7 +222,6 @@ struct exynos_drm_gem_obj *exynos_drm_gem_create(struct drm_device *dev,
 						unsigned long size)
 {
 	struct exynos_drm_gem_obj *exynos_gem_obj;
-	struct exynos_drm_gem_buf *buf;
 	int ret;
 
 	if (flags & ~(EXYNOS_BO_MASK)) {
@@ -144,33 +236,21 @@ struct exynos_drm_gem_obj *exynos_drm_gem_create(struct drm_device *dev,
 
 	size = roundup(size, PAGE_SIZE);
 
-	buf = exynos_drm_init_buf(dev, size);
-	if (!buf)
-		return ERR_PTR(-ENOMEM);
-
 	exynos_gem_obj = exynos_drm_gem_init(dev, size);
-	if (IS_ERR(exynos_gem_obj)) {
-		ret = PTR_ERR(exynos_gem_obj);
-		goto err_fini_buf;
-	}
-
-	exynos_gem_obj->buffer = buf;
+	if (IS_ERR(exynos_gem_obj))
+		return exynos_gem_obj;
 
 	/* set memory type and cache attribute from user side. */
 	exynos_gem_obj->flags = flags;
 
-	ret = exynos_drm_alloc_buf(dev, buf, flags);
-	if (ret < 0)
-		goto err_gem_fini;
+	ret = exynos_drm_alloc_buf(exynos_gem_obj);
+	if (ret < 0) {
+		drm_gem_object_release(&exynos_gem_obj->base);
+		kfree(exynos_gem_obj);
+		return ERR_PTR(ret);
+	}
 
 	return exynos_gem_obj;
-
-err_gem_fini:
-	drm_gem_object_release(&exynos_gem_obj->base);
-	kfree(exynos_gem_obj);
-err_fini_buf:
-	exynos_drm_fini_buf(dev, buf);
-	return ERR_PTR(ret);
 }
 
 int exynos_drm_gem_create_ioctl(struct drm_device *dev, void *data,
@@ -209,7 +289,7 @@ dma_addr_t *exynos_drm_gem_get_dma_addr(struct drm_device *dev,
 
 	exynos_gem_obj = to_exynos_gem_obj(obj);
 
-	return &exynos_gem_obj->buffer->dma_addr;
+	return &exynos_gem_obj->dma_addr;
 }
 
 void exynos_drm_gem_put_dma_addr(struct drm_device *dev,
@@ -237,7 +317,6 @@ int exynos_drm_gem_mmap_buffer(struct exynos_drm_gem_obj *exynos_gem_obj,
 				      struct vm_area_struct *vma)
 {
 	struct drm_device *drm_dev = exynos_gem_obj->base.dev;
-	struct exynos_drm_gem_buf *buffer;
 	unsigned long vm_size;
 	int ret;
 
@@ -246,19 +325,13 @@ int exynos_drm_gem_mmap_buffer(struct exynos_drm_gem_obj *exynos_gem_obj,
 
 	vm_size = vma->vm_end - vma->vm_start;
 
-	/*
-	 * a buffer contains information to physically continuous memory
-	 * allocated by user request or at framebuffer creation.
-	 */
-	buffer = exynos_gem_obj->buffer;
-
 	/* check if user-requested size is valid. */
-	if (vm_size > buffer->size)
+	if (vm_size > exynos_gem_obj->size)
 		return -EINVAL;
 
-	ret = dma_mmap_attrs(drm_dev->dev, vma, buffer->pages,
-				buffer->dma_addr, buffer->size,
-				&buffer->dma_attrs);
+	ret = dma_mmap_attrs(drm_dev->dev, vma, exynos_gem_obj->pages,
+				exynos_gem_obj->dma_addr, exynos_gem_obj->size,
+				&exynos_gem_obj->dma_attrs);
 	if (ret < 0) {
 		DRM_ERROR("failed to mmap.\n");
 		return ret;
@@ -418,12 +491,6 @@ void exynos_gem_unmap_sgt_from_dma(struct drm_device *drm_dev,
 
 void exynos_drm_gem_free_object(struct drm_gem_object *obj)
 {
-	struct exynos_drm_gem_obj *exynos_gem_obj;
-	struct exynos_drm_gem_buf *buf;
-
-	exynos_gem_obj = to_exynos_gem_obj(obj);
-	buf = exynos_gem_obj->buffer;
-
 	exynos_drm_gem_destroy(to_exynos_gem_obj(obj));
 }
 
@@ -508,7 +575,6 @@ int exynos_drm_gem_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
 {
 	struct drm_gem_object *obj = vma->vm_private_data;
 	struct exynos_drm_gem_obj *exynos_gem_obj = to_exynos_gem_obj(obj);
-	struct exynos_drm_gem_buf *buf = exynos_gem_obj->buffer;
 	unsigned long pfn;
 	pgoff_t page_offset;
 	int ret;
@@ -516,13 +582,13 @@ int exynos_drm_gem_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
 	page_offset = ((unsigned long)vmf->virtual_address -
 			vma->vm_start) >> PAGE_SHIFT;
 
-	if (page_offset >= (buf->size >> PAGE_SHIFT)) {
+	if (page_offset >= (exynos_gem_obj->size >> PAGE_SHIFT)) {
 		DRM_ERROR("invalid page offset\n");
 		ret = -EINVAL;
 		goto out;
 	}
 
-	pfn = page_to_pfn(buf->pages[page_offset]);
+	pfn = page_to_pfn(exynos_gem_obj->pages[page_offset]);
 	ret = vm_insert_mixed(vma, (unsigned long)vmf->virtual_address, pfn);
 
 out:
@@ -583,12 +649,11 @@ err_close_vm:
 struct sg_table *exynos_drm_gem_prime_get_sg_table(struct drm_gem_object *obj)
 {
 	struct exynos_drm_gem_obj *exynos_gem_obj = to_exynos_gem_obj(obj);
-	struct exynos_drm_gem_buf *buf = exynos_gem_obj->buffer;
 	int npages;
 
-	npages = buf->size >> PAGE_SHIFT;
+	npages = exynos_gem_obj->size >> PAGE_SHIFT;
 
-	return drm_prime_pages_to_sg(buf->pages, npages);
+	return drm_prime_pages_to_sg(exynos_gem_obj->pages, npages);
 }
 
 struct drm_gem_object *
@@ -597,34 +662,29 @@ exynos_drm_gem_prime_import_sg_table(struct drm_device *dev,
 				     struct sg_table *sgt)
 {
 	struct exynos_drm_gem_obj *exynos_gem_obj;
-	struct exynos_drm_gem_buf *buf;
 	int npages;
 	int ret;
 
-	buf = kzalloc(sizeof(*buf), GFP_KERNEL);
-	if (!buf)
-		return ERR_PTR(-ENOMEM);
+	exynos_gem_obj = exynos_drm_gem_init(dev, attach->dmabuf->size);
+	if (IS_ERR(exynos_gem_obj)) {
+		ret = PTR_ERR(exynos_gem_obj);
+		goto err;
+	}
 
-	buf->size = attach->dmabuf->size;
-	buf->dma_addr = sg_dma_address(sgt->sgl);
+	exynos_gem_obj->dma_addr = sg_dma_address(sgt->sgl);
 
-	npages = buf->size >> PAGE_SHIFT;
-	buf->pages = drm_malloc_ab(npages, sizeof(struct page *));
-	if (!buf->pages) {
+	npages = exynos_gem_obj->size >> PAGE_SHIFT;
+	exynos_gem_obj->pages = drm_malloc_ab(npages, sizeof(struct page *));
+	if (!exynos_gem_obj->pages) {
 		ret = -ENOMEM;
 		goto err;
 	}
 
-	ret = drm_prime_sg_to_page_addr_arrays(sgt, buf->pages, NULL, npages);
+	ret = drm_prime_sg_to_page_addr_arrays(sgt, exynos_gem_obj->pages, NULL,
+			npages);
 	if (ret < 0)
 		goto err_free_large;
 
-	exynos_gem_obj = exynos_drm_gem_init(dev, buf->size);
-	if (IS_ERR(exynos_gem_obj)) {
-		ret = PTR_ERR(exynos_gem_obj);
-		goto err;
-	}
-
 	if (sgt->nents == 1) {
 		/* always physically continuous memory if sgt->nents is 1. */
 		exynos_gem_obj->flags |= EXYNOS_BO_CONTIG;
@@ -641,9 +701,10 @@ exynos_drm_gem_prime_import_sg_table(struct drm_device *dev,
 	return &exynos_gem_obj->base;
 
 err_free_large:
-	drm_free_large(buf->pages);
+	drm_free_large(exynos_gem_obj->pages);
 err:
-	kfree(buf);
+	drm_gem_object_release(&exynos_gem_obj->base);
+	kfree(exynos_gem_obj);
 	return ERR_PTR(ret);
 }
 
diff --git a/drivers/gpu/drm/exynos/exynos_drm_gem.h b/drivers/gpu/drm/exynos/exynos_drm_gem.h
index 5e20da6e094e..cd62f8410d1e 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_gem.h
+++ b/drivers/gpu/drm/exynos/exynos_drm_gem.h
@@ -20,26 +20,6 @@
 #define IS_NONCONTIG_BUFFER(f)		(f & EXYNOS_BO_NONCONTIG)
 
 /*
- * exynos drm gem buffer structure.
- *
- * @cookie: cookie returned by dma_alloc_attrs
- * @kvaddr: kernel virtual address to allocated memory region.
- * @dma_addr: bus address(accessed by dma) to allocated memory region.
- *	- this address could be physical address without IOMMU and
- *	device address with IOMMU.
- * @pages: Array of backing pages.
- * @size: size of allocated memory region.
- */
-struct exynos_drm_gem_buf {
-	void 			*cookie;
-	void __iomem		*kvaddr;
-	dma_addr_t		dma_addr;
-	struct dma_attrs	dma_attrs;
-	struct page		**pages;
-	unsigned long		size;
-};
-
-/*
  * exynos drm buffer structure.
  *
  * @base: a gem object.
@@ -50,18 +30,28 @@ struct exynos_drm_gem_buf {
  *	by user request or at framebuffer creation.
  *	continuous memory region allocated by user request
  *	or at framebuffer creation.
+ * @flags: indicate memory type to allocated buffer and cache attruibute.
  * @size: size requested from user, in bytes and this size is aligned
  *	in page unit.
- * @flags: indicate memory type to allocated buffer and cache attruibute.
+ * @cookie: cookie returned by dma_alloc_attrs
+ * @kvaddr: kernel virtual address to allocated memory region.
+ * @dma_addr: bus address(accessed by dma) to allocated memory region.
+ *	- this address could be physical address without IOMMU and
+ *	device address with IOMMU.
+ * @pages: Array of backing pages.
  *
  * P.S. this object would be transferred to user as kms_bo.handle so
  *	user can access the buffer through kms_bo.handle.
  */
 struct exynos_drm_gem_obj {
-	struct drm_gem_object		base;
-	struct exynos_drm_gem_buf	*buffer;
-	unsigned long			size;
-	unsigned int			flags;
+	struct drm_gem_object	base;
+	unsigned int		flags;
+	unsigned long		size;
+	void			*cookie;
+	void __iomem		*kvaddr;
+	dma_addr_t		dma_addr;
+	struct dma_attrs	dma_attrs;
+	struct page		**pages;
 };
 
 struct page **exynos_gem_get_pages(struct drm_gem_object *obj, gfp_t gfpmask);
diff --git a/drivers/gpu/drm/exynos/exynos_drm_plane.c b/drivers/gpu/drm/exynos/exynos_drm_plane.c
index bebc9572d404..d9a68fd83120 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_plane.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_plane.c
@@ -134,15 +134,15 @@ static int exynos_plane_atomic_check(struct drm_plane *plane,
 
 	nr = exynos_drm_fb_get_buf_cnt(state->fb);
 	for (i = 0; i < nr; i++) {
-		struct exynos_drm_gem_buf *buffer =
-					exynos_drm_fb_buffer(state->fb, i);
+		struct exynos_drm_gem_obj *obj =
+					exynos_drm_fb_gem_obj(state->fb, i);
 
-		if (!buffer) {
-			DRM_DEBUG_KMS("buffer is null\n");
+		if (!obj) {
+			DRM_DEBUG_KMS("gem object is null\n");
 			return -EFAULT;
 		}
 
-		exynos_plane->dma_addr[i] = buffer->dma_addr +
+		exynos_plane->dma_addr[i] = obj->dma_addr +
 					    state->fb->offsets[i];
 
 		DRM_DEBUG_KMS("buffer: %d, dma_addr = 0x%lx\n",