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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Copyright (C) 2011 Texas Instruments Incorporated - https://www.ti.com/4 * Author: Rob Clark <rob.clark@linaro.org>5 */6 7#include <linux/dma-buf.h>8#include <linux/highmem.h>9 10#include <drm/drm_prime.h>11 12#include "omap_drv.h"13 14MODULE_IMPORT_NS(DMA_BUF);15 16/* -----------------------------------------------------------------------------17 * DMABUF Export18 */19 20static struct sg_table *omap_gem_map_dma_buf(21 struct dma_buf_attachment *attachment,22 enum dma_data_direction dir)23{24 struct drm_gem_object *obj = attachment->dmabuf->priv;25 struct sg_table *sg;26 sg = omap_gem_get_sg(obj, dir);27 if (IS_ERR(sg))28 return sg;29 30 return sg;31}32 33static void omap_gem_unmap_dma_buf(struct dma_buf_attachment *attachment,34 struct sg_table *sg, enum dma_data_direction dir)35{36 struct drm_gem_object *obj = attachment->dmabuf->priv;37 omap_gem_put_sg(obj, sg);38}39 40static int omap_gem_dmabuf_begin_cpu_access(struct dma_buf *buffer,41 enum dma_data_direction dir)42{43 struct drm_gem_object *obj = buffer->priv;44 struct page **pages;45 if (omap_gem_flags(obj) & OMAP_BO_TILED_MASK) {46 /* TODO we would need to pin at least part of the buffer to47 * get de-tiled view. For now just reject it.48 */49 return -ENOMEM;50 }51 /* make sure we have the pages: */52 return omap_gem_get_pages(obj, &pages, true);53}54 55static int omap_gem_dmabuf_end_cpu_access(struct dma_buf *buffer,56 enum dma_data_direction dir)57{58 struct drm_gem_object *obj = buffer->priv;59 omap_gem_put_pages(obj);60 return 0;61}62 63static int omap_gem_dmabuf_mmap(struct dma_buf *buffer,64 struct vm_area_struct *vma)65{66 struct drm_gem_object *obj = buffer->priv;67 68 return drm_gem_mmap_obj(obj, omap_gem_mmap_size(obj), vma);69}70 71static const struct dma_buf_ops omap_dmabuf_ops = {72 .map_dma_buf = omap_gem_map_dma_buf,73 .unmap_dma_buf = omap_gem_unmap_dma_buf,74 .release = drm_gem_dmabuf_release,75 .begin_cpu_access = omap_gem_dmabuf_begin_cpu_access,76 .end_cpu_access = omap_gem_dmabuf_end_cpu_access,77 .mmap = omap_gem_dmabuf_mmap,78};79 80struct dma_buf *omap_gem_prime_export(struct drm_gem_object *obj, int flags)81{82 DEFINE_DMA_BUF_EXPORT_INFO(exp_info);83 84 exp_info.ops = &omap_dmabuf_ops;85 exp_info.size = omap_gem_mmap_size(obj);86 exp_info.flags = flags;87 exp_info.priv = obj;88 exp_info.resv = obj->resv;89 90 return drm_gem_dmabuf_export(obj->dev, &exp_info);91}92 93/* -----------------------------------------------------------------------------94 * DMABUF Import95 */96 97struct drm_gem_object *omap_gem_prime_import(struct drm_device *dev,98 struct dma_buf *dma_buf)99{100 struct dma_buf_attachment *attach;101 struct drm_gem_object *obj;102 struct sg_table *sgt;103 int ret;104 105 if (dma_buf->ops == &omap_dmabuf_ops) {106 obj = dma_buf->priv;107 if (obj->dev == dev) {108 /*109 * Importing dmabuf exported from out own gem increases110 * refcount on gem itself instead of f_count of dmabuf.111 */112 drm_gem_object_get(obj);113 return obj;114 }115 }116 117 attach = dma_buf_attach(dma_buf, dev->dev);118 if (IS_ERR(attach))119 return ERR_CAST(attach);120 121 get_dma_buf(dma_buf);122 123 sgt = dma_buf_map_attachment_unlocked(attach, DMA_TO_DEVICE);124 if (IS_ERR(sgt)) {125 ret = PTR_ERR(sgt);126 goto fail_detach;127 }128 129 obj = omap_gem_new_dmabuf(dev, dma_buf->size, sgt);130 if (IS_ERR(obj)) {131 ret = PTR_ERR(obj);132 goto fail_unmap;133 }134 135 obj->import_attach = attach;136 137 return obj;138 139fail_unmap:140 dma_buf_unmap_attachment_unlocked(attach, sgt, DMA_TO_DEVICE);141fail_detach:142 dma_buf_detach(dma_buf, attach);143 dma_buf_put(dma_buf);144 145 return ERR_PTR(ret);146}147