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nouveau_prime.c
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1 /*
2  * Copyright 2011 Red Hat Inc.
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining a
5  * copy of this software and associated documentation files (the "Software"),
6  * to deal in the Software without restriction, including without limitation
7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8  * and/or sell copies of the Software, and to permit persons to whom the
9  * Software is furnished to do so, subject to the following conditions:
10  *
11  * The above copyright notice and this permission notice shall be included in
12  * all copies or substantial portions of the Software.
13  *
14  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
17  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
18  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
19  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
20  * OTHER DEALINGS IN THE SOFTWARE.
21  *
22  * Authors: Dave Airlie
23  */
24 
25 #include <linux/dma-buf.h>
26 
27 #include <drm/drmP.h>
28 
29 #include "nouveau_drm.h"
30 #include "nouveau_gem.h"
31 
32 static struct sg_table *nouveau_gem_map_dma_buf(struct dma_buf_attachment *attachment,
33  enum dma_data_direction dir)
34 {
35  struct nouveau_bo *nvbo = attachment->dmabuf->priv;
36  struct drm_device *dev = nvbo->gem->dev;
37  int npages = nvbo->bo.num_pages;
38  struct sg_table *sg;
39  int nents;
40 
41  mutex_lock(&dev->struct_mutex);
42  sg = drm_prime_pages_to_sg(nvbo->bo.ttm->pages, npages);
43  nents = dma_map_sg(attachment->dev, sg->sgl, sg->nents, dir);
44  mutex_unlock(&dev->struct_mutex);
45  return sg;
46 }
47 
48 static void nouveau_gem_unmap_dma_buf(struct dma_buf_attachment *attachment,
49  struct sg_table *sg, enum dma_data_direction dir)
50 {
51  dma_unmap_sg(attachment->dev, sg->sgl, sg->nents, dir);
52  sg_free_table(sg);
53  kfree(sg);
54 }
55 
56 static void nouveau_gem_dmabuf_release(struct dma_buf *dma_buf)
57 {
58  struct nouveau_bo *nvbo = dma_buf->priv;
59 
60  if (nvbo->gem->export_dma_buf == dma_buf) {
61  nvbo->gem->export_dma_buf = NULL;
62  drm_gem_object_unreference_unlocked(nvbo->gem);
63  }
64 }
65 
66 static void *nouveau_gem_kmap_atomic(struct dma_buf *dma_buf, unsigned long page_num)
67 {
68  return NULL;
69 }
70 
71 static void nouveau_gem_kunmap_atomic(struct dma_buf *dma_buf, unsigned long page_num, void *addr)
72 {
73 
74 }
75 static void *nouveau_gem_kmap(struct dma_buf *dma_buf, unsigned long page_num)
76 {
77  return NULL;
78 }
79 
80 static void nouveau_gem_kunmap(struct dma_buf *dma_buf, unsigned long page_num, void *addr)
81 {
82 
83 }
84 
85 static int nouveau_gem_prime_mmap(struct dma_buf *dma_buf, struct vm_area_struct *vma)
86 {
87  return -EINVAL;
88 }
89 
90 static void *nouveau_gem_prime_vmap(struct dma_buf *dma_buf)
91 {
92  struct nouveau_bo *nvbo = dma_buf->priv;
93  struct drm_device *dev = nvbo->gem->dev;
94  int ret;
95 
96  mutex_lock(&dev->struct_mutex);
97  if (nvbo->vmapping_count) {
98  nvbo->vmapping_count++;
99  goto out_unlock;
100  }
101 
102  ret = ttm_bo_kmap(&nvbo->bo, 0, nvbo->bo.num_pages,
103  &nvbo->dma_buf_vmap);
104  if (ret) {
105  mutex_unlock(&dev->struct_mutex);
106  return ERR_PTR(ret);
107  }
108  nvbo->vmapping_count = 1;
109 out_unlock:
110  mutex_unlock(&dev->struct_mutex);
111  return nvbo->dma_buf_vmap.virtual;
112 }
113 
114 static void nouveau_gem_prime_vunmap(struct dma_buf *dma_buf, void *vaddr)
115 {
116  struct nouveau_bo *nvbo = dma_buf->priv;
117  struct drm_device *dev = nvbo->gem->dev;
118 
119  mutex_lock(&dev->struct_mutex);
120  nvbo->vmapping_count--;
121  if (nvbo->vmapping_count == 0) {
122  ttm_bo_kunmap(&nvbo->dma_buf_vmap);
123  }
124  mutex_unlock(&dev->struct_mutex);
125 }
126 
127 static const struct dma_buf_ops nouveau_dmabuf_ops = {
128  .map_dma_buf = nouveau_gem_map_dma_buf,
129  .unmap_dma_buf = nouveau_gem_unmap_dma_buf,
130  .release = nouveau_gem_dmabuf_release,
131  .kmap = nouveau_gem_kmap,
132  .kmap_atomic = nouveau_gem_kmap_atomic,
133  .kunmap = nouveau_gem_kunmap,
134  .kunmap_atomic = nouveau_gem_kunmap_atomic,
135  .mmap = nouveau_gem_prime_mmap,
136  .vmap = nouveau_gem_prime_vmap,
137  .vunmap = nouveau_gem_prime_vunmap,
138 };
139 
140 static int
141 nouveau_prime_new(struct drm_device *dev,
142  size_t size,
143  struct sg_table *sg,
144  struct nouveau_bo **pnvbo)
145 {
146  struct nouveau_bo *nvbo;
147  u32 flags = 0;
148  int ret;
149 
150  flags = TTM_PL_FLAG_TT;
151 
152  ret = nouveau_bo_new(dev, size, 0, flags, 0, 0,
153  sg, pnvbo);
154  if (ret)
155  return ret;
156  nvbo = *pnvbo;
157 
158  /* we restrict allowed domains on nv50+ to only the types
159  * that were requested at creation time. not possibly on
160  * earlier chips without busting the ABI.
161  */
163  nvbo->gem = drm_gem_object_alloc(dev, nvbo->bo.mem.size);
164  if (!nvbo->gem) {
165  nouveau_bo_ref(NULL, pnvbo);
166  return -ENOMEM;
167  }
168 
169  nvbo->gem->driver_private = nvbo;
170  return 0;
171 }
172 
173 struct dma_buf *nouveau_gem_prime_export(struct drm_device *dev,
174  struct drm_gem_object *obj, int flags)
175 {
176  struct nouveau_bo *nvbo = nouveau_gem_object(obj);
177  int ret = 0;
178 
179  /* pin buffer into GTT */
180  ret = nouveau_bo_pin(nvbo, TTM_PL_FLAG_TT);
181  if (ret)
182  return ERR_PTR(-EINVAL);
183 
184  return dma_buf_export(nvbo, &nouveau_dmabuf_ops, obj->size, flags);
185 }
186 
187 struct drm_gem_object *nouveau_gem_prime_import(struct drm_device *dev,
188  struct dma_buf *dma_buf)
189 {
190  struct dma_buf_attachment *attach;
191  struct sg_table *sg;
192  struct nouveau_bo *nvbo;
193  int ret;
194 
195  if (dma_buf->ops == &nouveau_dmabuf_ops) {
196  nvbo = dma_buf->priv;
197  if (nvbo->gem) {
198  if (nvbo->gem->dev == dev) {
199  drm_gem_object_reference(nvbo->gem);
200  return nvbo->gem;
201  }
202  }
203  }
204  /* need to attach */
205  attach = dma_buf_attach(dma_buf, dev->dev);
206  if (IS_ERR(attach))
207  return ERR_PTR(PTR_ERR(attach));
208 
210  if (IS_ERR(sg)) {
211  ret = PTR_ERR(sg);
212  goto fail_detach;
213  }
214 
215  ret = nouveau_prime_new(dev, dma_buf->size, sg, &nvbo);
216  if (ret)
217  goto fail_unmap;
218 
219  nvbo->gem->import_attach = attach;
220 
221  return nvbo->gem;
222 
223 fail_unmap:
225 fail_detach:
226  dma_buf_detach(dma_buf, attach);
227  return ERR_PTR(ret);
228 }
229