drm/exynos: update gem and buffer framework. (2b35892e) · Commits · e / devices / android_kernel_fairphone_FP5

drivers/gpu/drm/exynos/exynos_drm_buf.c

+156 −35

Original line number	Diff line number	Diff line
		@@ -25,44 +25,160 @@

		#include "drmP.h"
		#include "drm.h"
		#include "exynos_drm.h"

		#include "exynos_drm_drv.h"
		#include "exynos_drm_gem.h"
		#include "exynos_drm_buf.h"

		static int lowlevel_buffer_allocate(struct drm_device *dev,
		struct exynos_drm_gem_buf *buffer)
		unsigned int flags, struct exynos_drm_gem_buf *buf)
		{
		dma_addr_t start_addr, end_addr;
		unsigned int npages, page_size, i = 0;
		struct scatterlist *sgl;
		int ret = 0;

		DRM_DEBUG_KMS("%s\n", __FILE__);

		buffer->kvaddr = dma_alloc_writecombine(dev->dev, buffer->size,
		&buffer->dma_addr, GFP_KERNEL);
		if (!buffer->kvaddr) {
		DRM_ERROR("failed to allocate buffer.\n");
		if (flags & EXYNOS_BO_NONCONTIG) {
		DRM_DEBUG_KMS("not support allocation type.\n");
		return -EINVAL;
		}

		if (buf->dma_addr) {
		DRM_DEBUG_KMS("already allocated.\n");
		return 0;
		}

		if (buf->size >= SZ_1M) {
		npages = (buf->size >> SECTION_SHIFT) + 1;
		page_size = SECTION_SIZE;
		} else if (buf->size >= SZ_64K) {
		npages = (buf->size >> 16) + 1;
		page_size = SZ_64K;
		} else {
		npages = (buf->size >> PAGE_SHIFT) + 1;
		page_size = PAGE_SIZE;
		}

		buf->sgt = kzalloc(sizeof(struct sg_table), GFP_KERNEL);
		if (!buf->sgt) {
		DRM_ERROR("failed to allocate sg table.\n");
		return -ENOMEM;
		}

		DRM_DEBUG_KMS("vaddr(0x%lx), dma_addr(0x%lx), size(0x%lx)\n",
		(unsigned long)buffer->kvaddr,
		(unsigned long)buffer->dma_addr,
		buffer->size);
		ret = sg_alloc_table(buf->sgt, npages, GFP_KERNEL);
		if (ret < 0) {
		DRM_ERROR("failed to initialize sg table.\n");
		kfree(buf->sgt);
		buf->sgt = NULL;
		return -ENOMEM;
		}

		return 0;
		buf->kvaddr = dma_alloc_writecombine(dev->dev, buf->size,
		&buf->dma_addr, GFP_KERNEL);
		if (!buf->kvaddr) {
		DRM_ERROR("failed to allocate buffer.\n");
		ret = -ENOMEM;
		goto err1;
		}

		start_addr = buf->dma_addr;
		end_addr = buf->dma_addr + buf->size;

		buf->pages = kzalloc(sizeof(struct page) * npages, GFP_KERNEL);
		if (!buf->pages) {
		DRM_ERROR("failed to allocate pages.\n");
		ret = -ENOMEM;
		goto err2;
		}

		start_addr = buf->dma_addr;
		end_addr = buf->dma_addr + buf->size;

		buf->pages = kzalloc(sizeof(struct page) * npages, GFP_KERNEL);
		if (!buf->pages) {
		DRM_ERROR("failed to allocate pages.\n");
		ret = -ENOMEM;
		goto err2;
		}

		sgl = buf->sgt->sgl;

		while (i < npages) {
		buf->pages[i] = phys_to_page(start_addr);
		sg_set_page(sgl, buf->pages[i], page_size, 0);
		sg_dma_address(sgl) = start_addr;
		start_addr += page_size;
		if (end_addr - start_addr < page_size)
		break;
		sgl = sg_next(sgl);
		i++;
		}

		buf->pages[i] = phys_to_page(start_addr);

		sgl = sg_next(sgl);
		sg_set_page(sgl, buf->pages[i+1], end_addr - start_addr, 0);

		DRM_DEBUG_KMS("vaddr(0x%lx), dma_addr(0x%lx), size(0x%lx)\n",
		(unsigned long)buf->kvaddr,
		(unsigned long)buf->dma_addr,
		buf->size);

		return ret;
		err2:
		dma_free_writecombine(dev->dev, buf->size, buf->kvaddr,
		(dma_addr_t)buf->dma_addr);
		buf->dma_addr = (dma_addr_t)NULL;
		err1:
		sg_free_table(buf->sgt);
		kfree(buf->sgt);
		buf->sgt = NULL;

		return ret;
		}

		static void lowlevel_buffer_deallocate(struct drm_device *dev,
		struct exynos_drm_gem_buf *buffer)
		unsigned int flags, struct exynos_drm_gem_buf *buf)
		{
		DRM_DEBUG_KMS("%s.\n", __FILE__);

		if (buffer->dma_addr && buffer->size)
		dma_free_writecombine(dev->dev, buffer->size, buffer->kvaddr,
		(dma_addr_t)buffer->dma_addr);
		else
		DRM_DEBUG_KMS("buffer data are invalid.\n");
		/*
		* release only physically continuous memory and
		* non-continuous memory would be released by exynos
		* gem framework.
		*/
		if (flags & EXYNOS_BO_NONCONTIG) {
		DRM_DEBUG_KMS("not support allocation type.\n");
		return;
		}

		if (!buf->dma_addr) {
		DRM_DEBUG_KMS("dma_addr is invalid.\n");
		return;
		}

		DRM_DEBUG_KMS("vaddr(0x%lx), dma_addr(0x%lx), size(0x%lx)\n",
		(unsigned long)buf->kvaddr,
		(unsigned long)buf->dma_addr,
		buf->size);

		sg_free_table(buf->sgt);

		kfree(buf->sgt);
		buf->sgt = NULL;

		kfree(buf->pages);
		buf->pages = NULL;

		dma_free_writecombine(dev->dev, buf->size, buf->kvaddr,
		(dma_addr_t)buf->dma_addr);
		buf->dma_addr = (dma_addr_t)NULL;
		}

		struct exynos_drm_gem_buf exynos_drm_buf_create(struct drm_device dev,
		struct exynos_drm_gem_buf exynos_drm_init_buf(struct drm_device dev,
		unsigned int size)
		{
		struct exynos_drm_gem_buf *buffer;
		@@ -77,20 +193,10 @@ struct exynos_drm_gem_buf exynos_drm_buf_create(struct drm_device dev,
		}

		buffer->size = size;

		/*
		* allocate memory region with size and set the memory information
		* to vaddr and dma_addr of a buffer object.
		*/
		if (lowlevel_buffer_allocate(dev, buffer) < 0) {
		kfree(buffer);
		return NULL;
		}

		return buffer;
		}

		void exynos_drm_buf_destroy(struct drm_device *dev,
		void exynos_drm_fini_buf(struct drm_device *dev,
		struct exynos_drm_gem_buf *buffer)
		{
		DRM_DEBUG_KMS("%s.\n", __FILE__);
		@@ -100,12 +206,27 @@ void exynos_drm_buf_destroy(struct drm_device *dev,
		return;
		}

		lowlevel_buffer_deallocate(dev, buffer);

		kfree(buffer);
		buffer = NULL;
		}

		MODULE_AUTHOR("Inki Dae <inki.dae@samsung.com>");
		MODULE_DESCRIPTION("Samsung SoC DRM Buffer Management Module");
		MODULE_LICENSE("GPL");
		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);
		}

drivers/gpu/drm/exynos/exynos_drm_buf.h

+16 −6

Original line number	Diff line number	Diff line
		@@ -26,12 +26,22 @@
		#ifndef _EXYNOS_DRM_BUF_H_
		#define _EXYNOS_DRM_BUF_H_

		/* allocate physical memory. */
		struct exynos_drm_gem_buf exynos_drm_buf_create(struct drm_device dev,
		/* create and initialize buffer object. */
		struct exynos_drm_gem_buf exynos_drm_init_buf(struct drm_device dev,
		unsigned int size);

		/* remove allocated physical memory. */
		void exynos_drm_buf_destroy(struct drm_device *dev,
		/* 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 and pages. */
		int exynos_drm_alloc_buf(struct drm_device *dev,
		struct exynos_drm_gem_buf *buf,
		unsigned int flags);

		/* release physical memory region, sgt and pages. */
		void exynos_drm_free_buf(struct drm_device *dev,
		unsigned int flags,
		struct exynos_drm_gem_buf *buffer);

		#endif

drivers/gpu/drm/exynos/exynos_drm_fbdev.c

+3 −1

Original line number	Diff line number	Diff line
		@@ -125,7 +125,9 @@ static int exynos_drm_fbdev_create(struct drm_fb_helper *helper,
		}

		size = mode_cmd.pitches[0] * mode_cmd.height;
		exynos_gem_obj = exynos_drm_gem_create(dev, size);

		/* 0 means to allocate physically continuous memory */
		exynos_gem_obj = exynos_drm_gem_create(dev, 0, size);
		if (IS_ERR(exynos_gem_obj)) {
		ret = PTR_ERR(exynos_gem_obj);
		goto out;

drivers/gpu/drm/exynos/exynos_drm_gem.c

+272 −29

Original line number	Diff line number	Diff line
		@@ -26,6 +26,7 @@
		#include "drmP.h"
		#include "drm.h"

		#include <linux/shmem_fs.h>
		#include <drm/exynos_drm.h>

		#include "exynos_drm_drv.h"
		@@ -55,6 +56,178 @@ static unsigned int convert_to_vm_err_msg(int msg)
		return out_msg;
		}

		static unsigned int mask_gem_flags(unsigned int flags)
		{
		return flags &= EXYNOS_BO_NONCONTIG;
		}

		static struct page *exynos_gem_get_pages(struct drm_gem_object obj,
		gfp_t gfpmask)
		{
		struct inode *inode;
		struct address_space *mapping;
		struct page p, *pages;
		int i, npages;

		/* This is the shared memory object that backs the GEM resource */
		inode = obj->filp->f_path.dentry->d_inode;
		mapping = inode->i_mapping;

		npages = obj->size >> PAGE_SHIFT;

		pages = drm_malloc_ab(npages, sizeof(struct page *));
		if (pages == NULL)
		return ERR_PTR(-ENOMEM);

		gfpmask \|= mapping_gfp_mask(mapping);

		for (i = 0; i < npages; i++) {
		p = shmem_read_mapping_page_gfp(mapping, i, gfpmask);
		if (IS_ERR(p))
		goto fail;
		pages[i] = p;
		}

		return pages;

		fail:
		while (i--)
		page_cache_release(pages[i]);

		drm_free_large(pages);
		return ERR_PTR(PTR_ERR(p));
		}

		static void exynos_gem_put_pages(struct drm_gem_object *obj,
		struct page **pages,
		bool dirty, bool accessed)
		{
		int i, npages;

		npages = obj->size >> PAGE_SHIFT;

		for (i = 0; i < npages; i++) {
		if (dirty)
		set_page_dirty(pages[i]);

		if (accessed)
		mark_page_accessed(pages[i]);

		/* Undo the reference we took when populating the table */
		page_cache_release(pages[i]);
		}

		drm_free_large(pages);
		}

		static int exynos_drm_gem_map_pages(struct drm_gem_object *obj,
		struct vm_area_struct *vma,
		unsigned long f_vaddr,
		pgoff_t page_offset)
		{
		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;

		if (exynos_gem_obj->flags & EXYNOS_BO_NONCONTIG) {
		unsigned long usize = buf->size;

		if (!buf->pages)
		return -EINTR;

		while (usize > 0) {
		pfn = page_to_pfn(buf->pages[page_offset++]);
		vm_insert_mixed(vma, f_vaddr, pfn);
		f_vaddr += PAGE_SIZE;
		usize -= PAGE_SIZE;
		}

		return 0;
		}

		pfn = (buf->dma_addr >> PAGE_SHIFT) + page_offset;

		return vm_insert_mixed(vma, f_vaddr, pfn);
		}

		static int exynos_drm_gem_get_pages(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;
		struct scatterlist *sgl;
		struct page **pages;
		unsigned int npages, i = 0;
		int ret;

		if (buf->pages) {
		DRM_DEBUG_KMS("already allocated.\n");
		return -EINVAL;
		}

		pages = exynos_gem_get_pages(obj, GFP_KERNEL);
		if (IS_ERR(pages)) {
		DRM_ERROR("failed to get pages.\n");
		return PTR_ERR(pages);
		}

		npages = obj->size >> PAGE_SHIFT;

		buf->sgt = kzalloc(sizeof(struct sg_table), GFP_KERNEL);
		if (!buf->sgt) {
		DRM_ERROR("failed to allocate sg table.\n");
		ret = -ENOMEM;
		goto err;
		}

		ret = sg_alloc_table(buf->sgt, npages, GFP_KERNEL);
		if (ret < 0) {
		DRM_ERROR("failed to initialize sg table.\n");
		ret = -EFAULT;
		goto err1;
		}

		sgl = buf->sgt->sgl;

		/* set all pages to sg list. */
		while (i < npages) {
		sg_set_page(sgl, pages[i], PAGE_SIZE, 0);
		sg_dma_address(sgl) = page_to_phys(pages[i]);
		i++;
		sgl = sg_next(sgl);
		}

		/* add some codes for UNCACHED type here. TODO */

		buf->pages = pages;
		return ret;
		err1:
		kfree(buf->sgt);
		buf->sgt = NULL;
		err:
		exynos_gem_put_pages(obj, pages, true, false);
		return ret;

		}

		static void exynos_drm_gem_put_pages(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;

		/*
		* if buffer typs is EXYNOS_BO_NONCONTIG then release all pages
		* allocated at gem fault handler.
		*/
		sg_free_table(buf->sgt);
		kfree(buf->sgt);
		buf->sgt = NULL;

		exynos_gem_put_pages(obj, buf->pages, true, false);
		buf->pages = NULL;

		/* add some codes for UNCACHED type here. TODO */
		}

		static int exynos_drm_gem_handle_create(struct drm_gem_object *obj,
		struct drm_file *file_priv,
		unsigned int *handle)
		@@ -90,7 +263,15 @@ void exynos_drm_gem_destroy(struct exynos_drm_gem_obj *exynos_gem_obj)

		DRM_DEBUG_KMS("handle count = %d\n", atomic_read(&obj->handle_count));

		exynos_drm_buf_destroy(obj->dev, exynos_gem_obj->buffer);
		if ((exynos_gem_obj->flags & EXYNOS_BO_NONCONTIG) &&
		exynos_gem_obj->buffer->pages)
		exynos_drm_gem_put_pages(obj);
		else
		exynos_drm_free_buf(obj->dev, exynos_gem_obj->flags,
		exynos_gem_obj->buffer);

		exynos_drm_fini_buf(obj->dev, exynos_gem_obj->buffer);
		exynos_gem_obj->buffer = NULL;

		if (obj->map_list.map)
		drm_gem_free_mmap_offset(obj);
		@@ -99,6 +280,7 @@ void exynos_drm_gem_destroy(struct exynos_drm_gem_obj *exynos_gem_obj)
		drm_gem_object_release(obj);

		kfree(exynos_gem_obj);
		exynos_gem_obj = NULL;
		}

		static struct exynos_drm_gem_obj exynos_drm_gem_init(struct drm_device dev,
		@@ -114,6 +296,7 @@ static struct exynos_drm_gem_obj exynos_drm_gem_init(struct drm_device dev,
		return NULL;
		}

		exynos_gem_obj->size = size;
		obj = &exynos_gem_obj->base;

		ret = drm_gem_object_init(dev, obj, size);
		@@ -129,27 +312,55 @@ static struct exynos_drm_gem_obj exynos_drm_gem_init(struct drm_device dev,
		}

		struct exynos_drm_gem_obj exynos_drm_gem_create(struct drm_device dev,
		unsigned int flags,
		unsigned long size)
		{
		struct exynos_drm_gem_buf *buffer;
		struct exynos_drm_gem_obj *exynos_gem_obj;
		struct exynos_drm_gem_buf *buf;
		int ret;

		size = roundup(size, PAGE_SIZE);
		DRM_DEBUG_KMS("%s: size = 0x%lx\n", __FILE__, size);

		buffer = exynos_drm_buf_create(dev, size);
		if (!buffer)
		flags = mask_gem_flags(flags);

		buf = exynos_drm_init_buf(dev, size);
		if (!buf)
		return ERR_PTR(-ENOMEM);

		exynos_gem_obj = exynos_drm_gem_init(dev, size);
		if (!exynos_gem_obj) {
		exynos_drm_buf_destroy(dev, buffer);
		return ERR_PTR(-ENOMEM);
		ret = -ENOMEM;
		goto err;
		}

		exynos_gem_obj->buffer = buffer;
		exynos_gem_obj->buffer = buf;

		/* set memory type and cache attribute from user side. */
		exynos_gem_obj->flags = flags;

		/*
		* allocate all pages as desired size if user wants to allocate
		* physically non-continuous memory.
		*/
		if (flags & EXYNOS_BO_NONCONTIG) {
		ret = exynos_drm_gem_get_pages(&exynos_gem_obj->base);
		if (ret < 0) {
		drm_gem_object_release(&exynos_gem_obj->base);
		goto err;
		}
		} else {
		ret = exynos_drm_alloc_buf(dev, buf, flags);
		if (ret < 0) {
		drm_gem_object_release(&exynos_gem_obj->base);
		goto err;
		}
		}

		return exynos_gem_obj;
		err:
		exynos_drm_fini_buf(dev, buf);
		return ERR_PTR(ret);
		}

		int exynos_drm_gem_create_ioctl(struct drm_device dev, void data,
		@@ -161,7 +372,7 @@ int exynos_drm_gem_create_ioctl(struct drm_device dev, void data,

		DRM_DEBUG_KMS("%s\n", __FILE__);

		exynos_gem_obj = exynos_drm_gem_create(dev, args->size);
		exynos_gem_obj = exynos_drm_gem_create(dev, args->flags, args->size);
		if (IS_ERR(exynos_gem_obj))
		return PTR_ERR(exynos_gem_obj);

		@@ -200,7 +411,8 @@ static int exynos_drm_gem_mmap_buffer(struct file *filp,
		struct drm_gem_object *obj = filp->private_data;
		struct exynos_drm_gem_obj *exynos_gem_obj = to_exynos_gem_obj(obj);
		struct exynos_drm_gem_buf *buffer;
		unsigned long pfn, vm_size;
		unsigned long pfn, vm_size, usize, uaddr = vma->vm_start;
		int ret;

		DRM_DEBUG_KMS("%s\n", __FILE__);

		@@ -209,7 +421,8 @@ static int exynos_drm_gem_mmap_buffer(struct file *filp,
		/* in case of direct mapping, always having non-cachable attribute */
		vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);

		vm_size = vma->vm_end - vma->vm_start;
		vm_size = usize = vma->vm_end - vma->vm_start;

		/*
		* a buffer contains information to physically continuous memory
		* allocated by user request or at framebuffer creation.
		@@ -220,11 +433,29 @@ static int exynos_drm_gem_mmap_buffer(struct file *filp,
		if (vm_size > buffer->size)
		return -EINVAL;

		if (exynos_gem_obj->flags & EXYNOS_BO_NONCONTIG) {
		int i = 0;

		if (!buffer->pages)
		return -EINVAL;

		do {
		ret = vm_insert_page(vma, uaddr, buffer->pages[i++]);
		if (ret) {
		DRM_ERROR("failed to remap user space.\n");
		return ret;
		}

		uaddr += PAGE_SIZE;
		usize -= PAGE_SIZE;
		} while (usize > 0);
		} else {
		/*
		* get page frame number to physical memory to be mapped
		* to user space.
		*/
		pfn = ((unsigned long)exynos_gem_obj->buffer->dma_addr) >> PAGE_SHIFT;
		pfn = ((unsigned long)exynos_gem_obj->buffer->dma_addr) >>
		PAGE_SHIFT;

		DRM_DEBUG_KMS("pfn = 0x%lx\n", pfn);

		@@ -233,6 +464,7 @@ static int exynos_drm_gem_mmap_buffer(struct file *filp,
		DRM_ERROR("failed to remap pfn range.\n");
		return -EAGAIN;
		}
		}

		return 0;
		}
		@@ -311,9 +543,9 @@ int exynos_drm_gem_dumb_create(struct drm_file *file_priv,
		*/

		args->pitch = args->width * args->bpp >> 3;
		args->size = args->pitch * args->height;
		args->size = PAGE_ALIGN(args->pitch * args->height);

		exynos_gem_obj = exynos_drm_gem_create(dev, args->size);
		exynos_gem_obj = exynos_drm_gem_create(dev, args->flags, args->size);
		if (IS_ERR(exynos_gem_obj))
		return PTR_ERR(exynos_gem_obj);

		@@ -397,20 +629,31 @@ 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 drm_device *dev = obj->dev;
		unsigned long pfn;
		unsigned long f_vaddr;
		pgoff_t page_offset;
		int ret;

		page_offset = ((unsigned long)vmf->virtual_address -
		vma->vm_start) >> PAGE_SHIFT;
		f_vaddr = (unsigned long)vmf->virtual_address;

		mutex_lock(&dev->struct_mutex);

		pfn = (((unsigned long)exynos_gem_obj->buffer->dma_addr) >>
		PAGE_SHIFT) + page_offset;
		/*
		* allocate all pages as desired size if user wants to allocate
		* physically non-continuous memory.
		*/
		if (exynos_gem_obj->flags & EXYNOS_BO_NONCONTIG) {
		ret = exynos_drm_gem_get_pages(obj);
		if (ret < 0)
		goto err;
		}

		ret = vm_insert_mixed(vma, (unsigned long)vmf->virtual_address, pfn);
		ret = exynos_drm_gem_map_pages(obj, vma, f_vaddr, page_offset);
		if (ret < 0)
		DRM_ERROR("failed to map pages.\n");

		err:
		mutex_unlock(&dev->struct_mutex);

		return convert_to_vm_err_msg(ret);

drivers/gpu/drm/exynos/exynos_drm_gem.h

+10 −1

Original line number	Diff line number	Diff line
		@@ -36,11 +36,15 @@
		* @dma_addr: bus address(accessed by dma) to allocated memory region.
		* - this address could be physical address without IOMMU and
		* device address with IOMMU.
		* @sgt: sg table to transfer page data.
		* @pages: contain all pages to allocated memory region.
		* @size: size of allocated memory region.
		*/
		struct exynos_drm_gem_buf {
		void __iomem *kvaddr;
		dma_addr_t dma_addr;
		struct sg_table *sgt;
		struct page **pages;
		unsigned long size;
		};

		@@ -55,6 +59,8 @@ struct exynos_drm_gem_buf {
		* by user request or at framebuffer creation.
		* continuous memory region allocated by user request
		* or at framebuffer creation.
		* @size: total memory size to physically non-continuous memory region.
		* @flags: indicate memory type to allocated buffer and cache attruibute.
		*
		* P.S. this object would be transfered to user as kms_bo.handle so
		* user can access the buffer through kms_bo.handle.
		@@ -62,6 +68,8 @@ struct exynos_drm_gem_buf {
		struct exynos_drm_gem_obj {
		struct drm_gem_object base;
		struct exynos_drm_gem_buf *buffer;
		unsigned long size;
		unsigned int flags;
		};

		/* destroy a buffer with gem object */
		@@ -69,6 +77,7 @@ void exynos_drm_gem_destroy(struct exynos_drm_gem_obj *exynos_gem_obj);

		/* create a new buffer with gem object */
		struct exynos_drm_gem_obj exynos_drm_gem_create(struct drm_device dev,
		unsigned int flags,
		unsigned long size);

		/*