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27#include <linux/dma-buf.h>
28#include <linux/reservation.h>
29
30#include <drm/drmP.h>
31
32#include "i915_drv.h"
33
34static struct drm_i915_gem_object *dma_buf_to_obj(struct dma_buf *buf)
35{
36 return to_intel_bo(buf->priv);
37}
38
39static struct sg_table *i915_gem_map_dma_buf(struct dma_buf_attachment *attachment,
40 enum dma_data_direction dir)
41{
42 struct drm_i915_gem_object *obj = dma_buf_to_obj(attachment->dmabuf);
43 struct sg_table *st;
44 struct scatterlist *src, *dst;
45 int ret, i;
46
47 ret = i915_gem_object_pin_pages(obj);
48 if (ret)
49 goto err;
50
51
52 st = kmalloc(sizeof(struct sg_table), GFP_KERNEL);
53 if (st == NULL) {
54 ret = -ENOMEM;
55 goto err_unpin_pages;
56 }
57
58 ret = sg_alloc_table(st, obj->mm.pages->nents, GFP_KERNEL);
59 if (ret)
60 goto err_free;
61
62 src = obj->mm.pages->sgl;
63 dst = st->sgl;
64 for (i = 0; i < obj->mm.pages->nents; i++) {
65 sg_set_page(dst, sg_page(src), src->length, 0);
66 dst = sg_next(dst);
67 src = sg_next(src);
68 }
69
70 if (!dma_map_sg(attachment->dev, st->sgl, st->nents, dir)) {
71 ret = -ENOMEM;
72 goto err_free_sg;
73 }
74
75 return st;
76
77err_free_sg:
78 sg_free_table(st);
79err_free:
80 kfree(st);
81err_unpin_pages:
82 i915_gem_object_unpin_pages(obj);
83err:
84 return ERR_PTR(ret);
85}
86
87static void i915_gem_unmap_dma_buf(struct dma_buf_attachment *attachment,
88 struct sg_table *sg,
89 enum dma_data_direction dir)
90{
91 struct drm_i915_gem_object *obj = dma_buf_to_obj(attachment->dmabuf);
92
93 dma_unmap_sg(attachment->dev, sg->sgl, sg->nents, dir);
94 sg_free_table(sg);
95 kfree(sg);
96
97 i915_gem_object_unpin_pages(obj);
98}
99
100static void *i915_gem_dmabuf_vmap(struct dma_buf *dma_buf)
101{
102 struct drm_i915_gem_object *obj = dma_buf_to_obj(dma_buf);
103
104 return i915_gem_object_pin_map(obj, I915_MAP_WB);
105}
106
107static void i915_gem_dmabuf_vunmap(struct dma_buf *dma_buf, void *vaddr)
108{
109 struct drm_i915_gem_object *obj = dma_buf_to_obj(dma_buf);
110
111 i915_gem_object_unpin_map(obj);
112}
113
114static void *i915_gem_dmabuf_kmap_atomic(struct dma_buf *dma_buf, unsigned long page_num)
115{
116 return NULL;
117}
118
119static void i915_gem_dmabuf_kunmap_atomic(struct dma_buf *dma_buf, unsigned long page_num, void *addr)
120{
121
122}
123static void *i915_gem_dmabuf_kmap(struct dma_buf *dma_buf, unsigned long page_num)
124{
125 struct drm_i915_gem_object *obj = dma_buf_to_obj(dma_buf);
126 struct page *page;
127
128 if (page_num >= obj->base.size >> PAGE_SHIFT)
129 return NULL;
130
131 if (!i915_gem_object_has_struct_page(obj))
132 return NULL;
133
134 if (i915_gem_object_pin_pages(obj))
135 return NULL;
136
137
138 page = i915_gem_object_get_page(obj, page_num);
139 if (IS_ERR(page))
140 goto err_unpin;
141
142 return kmap(page);
143
144err_unpin:
145 i915_gem_object_unpin_pages(obj);
146 return NULL;
147}
148
149static void i915_gem_dmabuf_kunmap(struct dma_buf *dma_buf, unsigned long page_num, void *addr)
150{
151 struct drm_i915_gem_object *obj = dma_buf_to_obj(dma_buf);
152
153 kunmap(virt_to_page(addr));
154 i915_gem_object_unpin_pages(obj);
155}
156
157static int i915_gem_dmabuf_mmap(struct dma_buf *dma_buf, struct vm_area_struct *vma)
158{
159 struct drm_i915_gem_object *obj = dma_buf_to_obj(dma_buf);
160 int ret;
161
162 if (obj->base.size < vma->vm_end - vma->vm_start)
163 return -EINVAL;
164
165 if (!obj->base.filp)
166 return -ENODEV;
167
168 ret = call_mmap(obj->base.filp, vma);
169 if (ret)
170 return ret;
171
172 fput(vma->vm_file);
173 vma->vm_file = get_file(obj->base.filp);
174
175 return 0;
176}
177
178static int i915_gem_begin_cpu_access(struct dma_buf *dma_buf, enum dma_data_direction direction)
179{
180 struct drm_i915_gem_object *obj = dma_buf_to_obj(dma_buf);
181 struct drm_device *dev = obj->base.dev;
182 bool write = (direction == DMA_BIDIRECTIONAL || direction == DMA_TO_DEVICE);
183 int err;
184
185 err = i915_gem_object_pin_pages(obj);
186 if (err)
187 return err;
188
189 err = i915_mutex_lock_interruptible(dev);
190 if (err)
191 goto out;
192
193 err = i915_gem_object_set_to_cpu_domain(obj, write);
194 mutex_unlock(&dev->struct_mutex);
195
196out:
197 i915_gem_object_unpin_pages(obj);
198 return err;
199}
200
201static int i915_gem_end_cpu_access(struct dma_buf *dma_buf, enum dma_data_direction direction)
202{
203 struct drm_i915_gem_object *obj = dma_buf_to_obj(dma_buf);
204 struct drm_device *dev = obj->base.dev;
205 int err;
206
207 err = i915_gem_object_pin_pages(obj);
208 if (err)
209 return err;
210
211 err = i915_mutex_lock_interruptible(dev);
212 if (err)
213 goto out;
214
215 err = i915_gem_object_set_to_gtt_domain(obj, false);
216 mutex_unlock(&dev->struct_mutex);
217
218out:
219 i915_gem_object_unpin_pages(obj);
220 return err;
221}
222
223static const struct dma_buf_ops i915_dmabuf_ops = {
224 .map_dma_buf = i915_gem_map_dma_buf,
225 .unmap_dma_buf = i915_gem_unmap_dma_buf,
226 .release = drm_gem_dmabuf_release,
227 .map = i915_gem_dmabuf_kmap,
228 .map_atomic = i915_gem_dmabuf_kmap_atomic,
229 .unmap = i915_gem_dmabuf_kunmap,
230 .unmap_atomic = i915_gem_dmabuf_kunmap_atomic,
231 .mmap = i915_gem_dmabuf_mmap,
232 .vmap = i915_gem_dmabuf_vmap,
233 .vunmap = i915_gem_dmabuf_vunmap,
234 .begin_cpu_access = i915_gem_begin_cpu_access,
235 .end_cpu_access = i915_gem_end_cpu_access,
236};
237
238struct dma_buf *i915_gem_prime_export(struct drm_device *dev,
239 struct drm_gem_object *gem_obj, int flags)
240{
241 struct drm_i915_gem_object *obj = to_intel_bo(gem_obj);
242 DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
243
244 exp_info.ops = &i915_dmabuf_ops;
245 exp_info.size = gem_obj->size;
246 exp_info.flags = flags;
247 exp_info.priv = gem_obj;
248 exp_info.resv = obj->resv;
249
250 if (obj->ops->dmabuf_export) {
251 int ret = obj->ops->dmabuf_export(obj);
252 if (ret)
253 return ERR_PTR(ret);
254 }
255
256 return drm_gem_dmabuf_export(dev, &exp_info);
257}
258
259static struct sg_table *
260i915_gem_object_get_pages_dmabuf(struct drm_i915_gem_object *obj)
261{
262 return dma_buf_map_attachment(obj->base.import_attach,
263 DMA_BIDIRECTIONAL);
264}
265
266static void i915_gem_object_put_pages_dmabuf(struct drm_i915_gem_object *obj,
267 struct sg_table *pages)
268{
269 dma_buf_unmap_attachment(obj->base.import_attach, pages,
270 DMA_BIDIRECTIONAL);
271}
272
273static const struct drm_i915_gem_object_ops i915_gem_object_dmabuf_ops = {
274 .get_pages = i915_gem_object_get_pages_dmabuf,
275 .put_pages = i915_gem_object_put_pages_dmabuf,
276};
277
278struct drm_gem_object *i915_gem_prime_import(struct drm_device *dev,
279 struct dma_buf *dma_buf)
280{
281 struct dma_buf_attachment *attach;
282 struct drm_i915_gem_object *obj;
283 int ret;
284
285
286 if (dma_buf->ops == &i915_dmabuf_ops) {
287 obj = dma_buf_to_obj(dma_buf);
288
289 if (obj->base.dev == dev) {
290
291
292
293
294 return &i915_gem_object_get(obj)->base;
295 }
296 }
297
298
299 attach = dma_buf_attach(dma_buf, dev->dev);
300 if (IS_ERR(attach))
301 return ERR_CAST(attach);
302
303 get_dma_buf(dma_buf);
304
305 obj = i915_gem_object_alloc(to_i915(dev));
306 if (obj == NULL) {
307 ret = -ENOMEM;
308 goto fail_detach;
309 }
310
311 drm_gem_private_object_init(dev, &obj->base, dma_buf->size);
312 i915_gem_object_init(obj, &i915_gem_object_dmabuf_ops);
313 obj->base.import_attach = attach;
314 obj->resv = dma_buf->resv;
315
316
317
318
319
320
321
322
323 obj->base.read_domains = I915_GEM_DOMAIN_GTT;
324 obj->base.write_domain = 0;
325
326 return &obj->base;
327
328fail_detach:
329 dma_buf_detach(dma_buf, attach);
330 dma_buf_put(dma_buf);
331
332 return ERR_PTR(ret);
333}
334
335#if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
336#include "selftests/mock_dmabuf.c"
337#include "selftests/i915_gem_dmabuf.c"
338#endif
339