1 // SPDX-License-Identifier: GPL-2.0-or-later
5 * Copyright (c) 2014 The Chromium OS Authors
10 #include <linux/shmem_fs.h>
11 #include <linux/dma-buf.h>
13 struct udl_drm_dmabuf_attachment {
15 enum dma_data_direction dir;
19 static int udl_attach_dma_buf(struct dma_buf *dmabuf,
20 struct dma_buf_attachment *attach)
22 struct udl_drm_dmabuf_attachment *udl_attach;
24 DRM_DEBUG_PRIME("[DEV:%s] size:%zd\n", dev_name(attach->dev),
25 attach->dmabuf->size);
27 udl_attach = kzalloc(sizeof(*udl_attach), GFP_KERNEL);
31 udl_attach->dir = DMA_NONE;
32 attach->priv = udl_attach;
37 static void udl_detach_dma_buf(struct dma_buf *dmabuf,
38 struct dma_buf_attachment *attach)
40 struct udl_drm_dmabuf_attachment *udl_attach = attach->priv;
46 DRM_DEBUG_PRIME("[DEV:%s] size:%zd\n", dev_name(attach->dev),
47 attach->dmabuf->size);
49 sgt = &udl_attach->sgt;
51 if (udl_attach->dir != DMA_NONE)
52 dma_unmap_sg(attach->dev, sgt->sgl, sgt->nents,
60 static struct sg_table *udl_map_dma_buf(struct dma_buf_attachment *attach,
61 enum dma_data_direction dir)
63 struct udl_drm_dmabuf_attachment *udl_attach = attach->priv;
64 struct udl_gem_object *obj = to_udl_bo(attach->dmabuf->priv);
65 struct drm_device *dev = obj->base.dev;
66 struct udl_device *udl = dev->dev_private;
67 struct scatterlist *rd, *wr;
68 struct sg_table *sgt = NULL;
73 DRM_DEBUG_PRIME("[DEV:%s] size:%zd dir=%d\n", dev_name(attach->dev),
74 attach->dmabuf->size, dir);
76 /* just return current sgt if already requested. */
77 if (udl_attach->dir == dir && udl_attach->is_mapped)
78 return &udl_attach->sgt;
81 ret = udl_gem_get_pages(obj);
83 DRM_ERROR("failed to map pages.\n");
88 page_count = obj->base.size / PAGE_SIZE;
89 obj->sg = drm_prime_pages_to_sg(obj->pages, page_count);
90 if (IS_ERR(obj->sg)) {
91 DRM_ERROR("failed to allocate sgt.\n");
92 return ERR_CAST(obj->sg);
95 sgt = &udl_attach->sgt;
97 ret = sg_alloc_table(sgt, obj->sg->orig_nents, GFP_KERNEL);
99 DRM_ERROR("failed to alloc sgt.\n");
100 return ERR_PTR(-ENOMEM);
103 mutex_lock(&udl->gem_lock);
107 for (i = 0; i < sgt->orig_nents; ++i) {
108 sg_set_page(wr, sg_page(rd), rd->length, rd->offset);
113 if (dir != DMA_NONE) {
114 nents = dma_map_sg(attach->dev, sgt->sgl, sgt->orig_nents, dir);
116 DRM_ERROR("failed to map sgl with iommu.\n");
123 udl_attach->is_mapped = true;
124 udl_attach->dir = dir;
125 attach->priv = udl_attach;
128 mutex_unlock(&udl->gem_lock);
132 static void udl_unmap_dma_buf(struct dma_buf_attachment *attach,
133 struct sg_table *sgt,
134 enum dma_data_direction dir)
137 DRM_DEBUG_PRIME("[DEV:%s] size:%zd dir:%d\n", dev_name(attach->dev),
138 attach->dmabuf->size, dir);
141 static void *udl_dmabuf_kmap(struct dma_buf *dma_buf, unsigned long page_num)
148 static void udl_dmabuf_kunmap(struct dma_buf *dma_buf,
149 unsigned long page_num, void *addr)
154 static int udl_dmabuf_mmap(struct dma_buf *dma_buf,
155 struct vm_area_struct *vma)
162 static const struct dma_buf_ops udl_dmabuf_ops = {
163 .attach = udl_attach_dma_buf,
164 .detach = udl_detach_dma_buf,
165 .map_dma_buf = udl_map_dma_buf,
166 .unmap_dma_buf = udl_unmap_dma_buf,
167 .map = udl_dmabuf_kmap,
168 .unmap = udl_dmabuf_kunmap,
169 .mmap = udl_dmabuf_mmap,
170 .release = drm_gem_dmabuf_release,
173 struct dma_buf *udl_gem_prime_export(struct drm_device *dev,
174 struct drm_gem_object *obj, int flags)
176 DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
178 exp_info.ops = &udl_dmabuf_ops;
179 exp_info.size = obj->size;
180 exp_info.flags = flags;
183 return drm_gem_dmabuf_export(dev, &exp_info);
186 static int udl_prime_create(struct drm_device *dev,
189 struct udl_gem_object **obj_p)
191 struct udl_gem_object *obj;
194 npages = size / PAGE_SIZE;
197 obj = udl_gem_alloc_object(dev, npages * PAGE_SIZE);
202 obj->pages = kvmalloc_array(npages, sizeof(struct page *), GFP_KERNEL);
203 if (obj->pages == NULL) {
204 DRM_ERROR("obj pages is NULL %d\n", npages);
208 drm_prime_sg_to_page_addr_arrays(sg, obj->pages, NULL, npages);
214 struct drm_gem_object *udl_gem_prime_import(struct drm_device *dev,
215 struct dma_buf *dma_buf)
217 struct dma_buf_attachment *attach;
219 struct udl_gem_object *uobj;
223 get_device(dev->dev);
224 attach = dma_buf_attach(dma_buf, dev->dev);
225 if (IS_ERR(attach)) {
226 put_device(dev->dev);
227 return ERR_CAST(attach);
230 get_dma_buf(dma_buf);
232 sg = dma_buf_map_attachment(attach, DMA_BIDIRECTIONAL);
238 ret = udl_prime_create(dev, dma_buf->size, sg, &uobj);
242 uobj->base.import_attach = attach;
243 uobj->flags = UDL_BO_WC;
248 dma_buf_unmap_attachment(attach, sg, DMA_BIDIRECTIONAL);
250 dma_buf_detach(dma_buf, attach);
251 dma_buf_put(dma_buf);
252 put_device(dev->dev);