4 * Copyright (c) 2014 The Chromium OS Authors
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License as published by the
8 * Free Software Foundation; either version 2 of the License, or (at your
9 * option) any later version.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program. If not, see <http://www.gnu.org/licenses/>.
22 #include <linux/shmem_fs.h>
23 #include <linux/dma-buf.h>
25 struct udl_drm_dmabuf_attachment {
27 enum dma_data_direction dir;
31 static int udl_attach_dma_buf(struct dma_buf *dmabuf,
32 struct dma_buf_attachment *attach)
34 struct udl_drm_dmabuf_attachment *udl_attach;
36 DRM_DEBUG_PRIME("[DEV:%s] size:%zd\n", dev_name(attach->dev),
37 attach->dmabuf->size);
39 udl_attach = kzalloc(sizeof(*udl_attach), GFP_KERNEL);
43 udl_attach->dir = DMA_NONE;
44 attach->priv = udl_attach;
49 static void udl_detach_dma_buf(struct dma_buf *dmabuf,
50 struct dma_buf_attachment *attach)
52 struct udl_drm_dmabuf_attachment *udl_attach = attach->priv;
58 DRM_DEBUG_PRIME("[DEV:%s] size:%zd\n", dev_name(attach->dev),
59 attach->dmabuf->size);
61 sgt = &udl_attach->sgt;
63 if (udl_attach->dir != DMA_NONE)
64 dma_unmap_sg(attach->dev, sgt->sgl, sgt->nents,
72 static struct sg_table *udl_map_dma_buf(struct dma_buf_attachment *attach,
73 enum dma_data_direction dir)
75 struct udl_drm_dmabuf_attachment *udl_attach = attach->priv;
76 struct udl_gem_object *obj = to_udl_bo(attach->dmabuf->priv);
77 struct drm_device *dev = obj->base.dev;
78 struct udl_device *udl = dev->dev_private;
79 struct scatterlist *rd, *wr;
80 struct sg_table *sgt = NULL;
85 DRM_DEBUG_PRIME("[DEV:%s] size:%zd dir=%d\n", dev_name(attach->dev),
86 attach->dmabuf->size, dir);
88 /* just return current sgt if already requested. */
89 if (udl_attach->dir == dir && udl_attach->is_mapped)
90 return &udl_attach->sgt;
93 ret = udl_gem_get_pages(obj);
95 DRM_ERROR("failed to map pages.\n");
100 page_count = obj->base.size / PAGE_SIZE;
101 obj->sg = drm_prime_pages_to_sg(obj->pages, page_count);
102 if (IS_ERR(obj->sg)) {
103 DRM_ERROR("failed to allocate sgt.\n");
104 return ERR_CAST(obj->sg);
107 sgt = &udl_attach->sgt;
109 ret = sg_alloc_table(sgt, obj->sg->orig_nents, GFP_KERNEL);
111 DRM_ERROR("failed to alloc sgt.\n");
112 return ERR_PTR(-ENOMEM);
115 mutex_lock(&udl->gem_lock);
119 for (i = 0; i < sgt->orig_nents; ++i) {
120 sg_set_page(wr, sg_page(rd), rd->length, rd->offset);
125 if (dir != DMA_NONE) {
126 nents = dma_map_sg(attach->dev, sgt->sgl, sgt->orig_nents, dir);
128 DRM_ERROR("failed to map sgl with iommu.\n");
135 udl_attach->is_mapped = true;
136 udl_attach->dir = dir;
137 attach->priv = udl_attach;
140 mutex_unlock(&udl->gem_lock);
144 static void udl_unmap_dma_buf(struct dma_buf_attachment *attach,
145 struct sg_table *sgt,
146 enum dma_data_direction dir)
149 DRM_DEBUG_PRIME("[DEV:%s] size:%zd dir:%d\n", dev_name(attach->dev),
150 attach->dmabuf->size, dir);
153 static void *udl_dmabuf_kmap(struct dma_buf *dma_buf, unsigned long page_num)
160 static void udl_dmabuf_kunmap(struct dma_buf *dma_buf,
161 unsigned long page_num, void *addr)
166 static int udl_dmabuf_mmap(struct dma_buf *dma_buf,
167 struct vm_area_struct *vma)
174 static const struct dma_buf_ops udl_dmabuf_ops = {
175 .attach = udl_attach_dma_buf,
176 .detach = udl_detach_dma_buf,
177 .map_dma_buf = udl_map_dma_buf,
178 .unmap_dma_buf = udl_unmap_dma_buf,
179 .map = udl_dmabuf_kmap,
180 .unmap = udl_dmabuf_kunmap,
181 .mmap = udl_dmabuf_mmap,
182 .release = drm_gem_dmabuf_release,
185 struct dma_buf *udl_gem_prime_export(struct drm_device *dev,
186 struct drm_gem_object *obj, int flags)
188 DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
190 exp_info.ops = &udl_dmabuf_ops;
191 exp_info.size = obj->size;
192 exp_info.flags = flags;
195 return drm_gem_dmabuf_export(dev, &exp_info);
198 static int udl_prime_create(struct drm_device *dev,
201 struct udl_gem_object **obj_p)
203 struct udl_gem_object *obj;
206 npages = size / PAGE_SIZE;
209 obj = udl_gem_alloc_object(dev, npages * PAGE_SIZE);
214 obj->pages = kvmalloc_array(npages, sizeof(struct page *), GFP_KERNEL);
215 if (obj->pages == NULL) {
216 DRM_ERROR("obj pages is NULL %d\n", npages);
220 drm_prime_sg_to_page_addr_arrays(sg, obj->pages, NULL, npages);
226 struct drm_gem_object *udl_gem_prime_import(struct drm_device *dev,
227 struct dma_buf *dma_buf)
229 struct dma_buf_attachment *attach;
231 struct udl_gem_object *uobj;
235 get_device(dev->dev);
236 attach = dma_buf_attach(dma_buf, dev->dev);
237 if (IS_ERR(attach)) {
238 put_device(dev->dev);
239 return ERR_CAST(attach);
242 get_dma_buf(dma_buf);
244 sg = dma_buf_map_attachment(attach, DMA_BIDIRECTIONAL);
250 ret = udl_prime_create(dev, dma_buf->size, sg, &uobj);
254 uobj->base.import_attach = attach;
255 uobj->flags = UDL_BO_WC;
260 dma_buf_unmap_attachment(attach, sg, DMA_BIDIRECTIONAL);
262 dma_buf_detach(dma_buf, attach);
263 dma_buf_put(dma_buf);
264 put_device(dev->dev);