drivers/gpu/drm/i915/i915_gem_dmabuf.c

   1 /*
   2  * Copyright 2012 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 (including the next
  12  * paragraph) shall be included in all copies or substantial portions of the
  13  * Software.
  14  *
  15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  18  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  20  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  21  * DEALINGS IN THE SOFTWARE.
  22  *
  23  * Authors:
  24  *      Dave Airlie <airlied@redhat.com>
  25  */
  26 #include <drm/drmP.h>
  27 #include "i915_drv.h"
  28 #include <linux/dma-buf.h>
  29
  30 static struct drm_i915_gem_object *dma_buf_to_obj(struct dma_buf *buf)
  31 {
  32         return to_intel_bo(buf->priv);
  33 }
  34
  35 static struct sg_table *i915_gem_map_dma_buf(struct dma_buf_attachment *attachment,
  36                                              enum dma_data_direction dir)
  37 {
  38         struct drm_i915_gem_object *obj = dma_buf_to_obj(attachment->dmabuf);
  39         struct sg_table *st;
  40         struct scatterlist *src, *dst;
  41         int ret, i;
  42
  43         ret = i915_mutex_lock_interruptible(obj->base.dev);
  44         if (ret)
  45                 goto err;
  46
  47         ret = i915_gem_object_get_pages(obj);
  48         if (ret)
  49                 goto err_unlock;
  50
  51         i915_gem_object_pin_pages(obj);
  52
  53         /* Copy sg so that we make an independent mapping */
  54         st = kmalloc(sizeof(struct sg_table), GFP_KERNEL);
  55         if (st == NULL) {
  56                 ret = -ENOMEM;
  57                 goto err_unpin;
  58         }
  59
  60         ret = sg_alloc_table(st, obj->pages->nents, GFP_KERNEL);
  61         if (ret)
  62                 goto err_free;
  63
  64         src = obj->pages->sgl;
  65         dst = st->sgl;
  66         for (i = 0; i < obj->pages->nents; i++) {
  67                 sg_set_page(dst, sg_page(src), src->length, 0);
  68                 dst = sg_next(dst);
  69                 src = sg_next(src);
  70         }
  71
  72         if (!dma_map_sg(attachment->dev, st->sgl, st->nents, dir)) {
  73                 ret =-ENOMEM;
  74                 goto err_free_sg;
  75         }
  76
  77         mutex_unlock(&obj->base.dev->struct_mutex);
  78         return st;
  79
  80 err_free_sg:
  81         sg_free_table(st);
  82 err_free:
  83         kfree(st);
  84 err_unpin:
  85         i915_gem_object_unpin_pages(obj);
  86 err_unlock:
  87         mutex_unlock(&obj->base.dev->struct_mutex);
  88 err:
  89         return ERR_PTR(ret);
  90 }
  91
  92 static void i915_gem_unmap_dma_buf(struct dma_buf_attachment *attachment,
  93                                    struct sg_table *sg,
  94                                    enum dma_data_direction dir)
  95 {
  96         struct drm_i915_gem_object *obj = dma_buf_to_obj(attachment->dmabuf);
  97
  98         mutex_lock(&obj->base.dev->struct_mutex);
  99
 100         dma_unmap_sg(attachment->dev, sg->sgl, sg->nents, dir);
 101         sg_free_table(sg);
 102         kfree(sg);
 103
 104         i915_gem_object_unpin_pages(obj);
 105
 106         mutex_unlock(&obj->base.dev->struct_mutex);
 107 }
 108
 109 static void *i915_gem_dmabuf_vmap(struct dma_buf *dma_buf)
 110 {
 111         struct drm_i915_gem_object *obj = dma_buf_to_obj(dma_buf);
 112         struct drm_device *dev = obj->base.dev;
 113         struct sg_page_iter sg_iter;
 114         struct page **pages;
 115         int ret, i;
 116
 117         ret = i915_mutex_lock_interruptible(dev);
 118         if (ret)
 119                 return ERR_PTR(ret);
 120
 121         if (obj->dma_buf_vmapping) {
 122                 obj->vmapping_count++;
 123                 goto out_unlock;
 124         }
 125
 126         ret = i915_gem_object_get_pages(obj);
 127         if (ret)
 128                 goto err;
 129
 130         i915_gem_object_pin_pages(obj);
 131
 132         ret = -ENOMEM;
 133
 134         pages = drm_malloc_ab(obj->base.size >> PAGE_SHIFT, sizeof(*pages));
 135         if (pages == NULL)
 136                 goto err_unpin;
 137
 138         i = 0;
 139         for_each_sg_page(obj->pages->sgl, &sg_iter, obj->pages->nents, 0)
 140                 pages[i++] = sg_page_iter_page(&sg_iter);
 141
 142         obj->dma_buf_vmapping = vmap(pages, i, 0, PAGE_KERNEL);
 143         drm_free_large(pages);
 144
 145         if (!obj->dma_buf_vmapping)
 146                 goto err_unpin;
 147
 148         obj->vmapping_count = 1;
 149 out_unlock:
 150         mutex_unlock(&dev->struct_mutex);
 151         return obj->dma_buf_vmapping;
 152
 153 err_unpin:
 154         i915_gem_object_unpin_pages(obj);
 155 err:
 156         mutex_unlock(&dev->struct_mutex);
 157         return ERR_PTR(ret);
 158 }
 159
 160 static void i915_gem_dmabuf_vunmap(struct dma_buf *dma_buf, void *vaddr)
 161 {
 162         struct drm_i915_gem_object *obj = dma_buf_to_obj(dma_buf);
 163         struct drm_device *dev = obj->base.dev;
 164
 165         mutex_lock(&dev->struct_mutex);
 166         if (--obj->vmapping_count == 0) {
 167                 vunmap(obj->dma_buf_vmapping);
 168                 obj->dma_buf_vmapping = NULL;
 169
 170                 i915_gem_object_unpin_pages(obj);
 171         }
 172         mutex_unlock(&dev->struct_mutex);
 173 }
 174
 175 static void *i915_gem_dmabuf_kmap_atomic(struct dma_buf *dma_buf, unsigned long page_num)
 176 {
 177         return NULL;
 178 }
 179
 180 static void i915_gem_dmabuf_kunmap_atomic(struct dma_buf *dma_buf, unsigned long page_num, void *addr)
 181 {
 182
 183 }
 184 static void *i915_gem_dmabuf_kmap(struct dma_buf *dma_buf, unsigned long page_num)
 185 {
 186         return NULL;
 187 }
 188
 189 static void i915_gem_dmabuf_kunmap(struct dma_buf *dma_buf, unsigned long page_num, void *addr)
 190 {
 191
 192 }
 193
 194 static int i915_gem_dmabuf_mmap(struct dma_buf *dma_buf, struct vm_area_struct *vma)
 195 {
 196         struct drm_i915_gem_object *obj = dma_buf_to_obj(dma_buf);
 197         int ret;
 198
 199         if (obj->base.size < vma->vm_end - vma->vm_start)
 200                 return -EINVAL;
 201
 202         if (!obj->base.filp)
 203                 return -ENODEV;
 204
 205         ret = obj->base.filp->f_op->mmap(obj->base.filp, vma);
 206         if (ret)
 207                 return ret;
 208
 209         fput(vma->vm_file);
 210         vma->vm_file = get_file(obj->base.filp);
 211
 212         return 0;
 213 }
 214
 215 static int i915_gem_begin_cpu_access(struct dma_buf *dma_buf, enum dma_data_direction direction)
 216 {
 217         struct drm_i915_gem_object *obj = dma_buf_to_obj(dma_buf);
 218         struct drm_device *dev = obj->base.dev;
 219         int ret;
 220         bool write = (direction == DMA_BIDIRECTIONAL || direction == DMA_TO_DEVICE);
 221
 222         ret = i915_mutex_lock_interruptible(dev);
 223         if (ret)
 224                 return ret;
 225
 226         ret = i915_gem_object_set_to_cpu_domain(obj, write);
 227         mutex_unlock(&dev->struct_mutex);
 228         return ret;
 229 }
 230
 231 static void i915_gem_end_cpu_access(struct dma_buf *dma_buf, enum dma_data_direction direction)
 232 {
 233         struct drm_i915_gem_object *obj = dma_buf_to_obj(dma_buf);
 234         struct drm_device *dev = obj->base.dev;
 235         struct drm_i915_private *dev_priv = to_i915(dev);
 236         bool was_interruptible;
 237         int ret;
 238
 239         mutex_lock(&dev->struct_mutex);
 240         was_interruptible = dev_priv->mm.interruptible;
 241         dev_priv->mm.interruptible = false;
 242
 243         ret = i915_gem_object_set_to_gtt_domain(obj, false);
 244
 245         dev_priv->mm.interruptible = was_interruptible;
 246         mutex_unlock(&dev->struct_mutex);
 247
 248         if (unlikely(ret))
 249                 DRM_ERROR("unable to flush buffer following CPU access; rendering may be corrupt\n");
 250 }
 251
 252 static const struct dma_buf_ops i915_dmabuf_ops =  {
 253         .map_dma_buf = i915_gem_map_dma_buf,
 254         .unmap_dma_buf = i915_gem_unmap_dma_buf,
 255         .release = drm_gem_dmabuf_release,
 256         .kmap = i915_gem_dmabuf_kmap,
 257         .kmap_atomic = i915_gem_dmabuf_kmap_atomic,
 258         .kunmap = i915_gem_dmabuf_kunmap,
 259         .kunmap_atomic = i915_gem_dmabuf_kunmap_atomic,
 260         .mmap = i915_gem_dmabuf_mmap,
 261         .vmap = i915_gem_dmabuf_vmap,
 262         .vunmap = i915_gem_dmabuf_vunmap,
 263         .begin_cpu_access = i915_gem_begin_cpu_access,
 264         .end_cpu_access = i915_gem_end_cpu_access,
 265 };
 266
 267 struct dma_buf *i915_gem_prime_export(struct drm_device *dev,
 268                                       struct drm_gem_object *gem_obj, int flags)
 269 {
 270         struct drm_i915_gem_object *obj = to_intel_bo(gem_obj);
 271         DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
 272
 273         exp_info.ops = &i915_dmabuf_ops;
 274         exp_info.size = gem_obj->size;
 275         exp_info.flags = flags;
 276         exp_info.priv = gem_obj;
 277
 278
 279         if (obj->ops->dmabuf_export) {
 280                 int ret = obj->ops->dmabuf_export(obj);
 281                 if (ret)
 282                         return ERR_PTR(ret);
 283         }
 284
 285         return dma_buf_export(&exp_info);
 286 }
 287
 288 static int i915_gem_object_get_pages_dmabuf(struct drm_i915_gem_object *obj)
 289 {
 290         struct sg_table *sg;
 291
 292         sg = dma_buf_map_attachment(obj->base.import_attach, DMA_BIDIRECTIONAL);
 293         if (IS_ERR(sg))
 294                 return PTR_ERR(sg);
 295
 296         obj->pages = sg;
 297         return 0;
 298 }
 299
 300 static void i915_gem_object_put_pages_dmabuf(struct drm_i915_gem_object *obj)
 301 {
 302         dma_buf_unmap_attachment(obj->base.import_attach,
 303                                  obj->pages, DMA_BIDIRECTIONAL);
 304 }
 305
 306 static const struct drm_i915_gem_object_ops i915_gem_object_dmabuf_ops = {
 307         .get_pages = i915_gem_object_get_pages_dmabuf,
 308         .put_pages = i915_gem_object_put_pages_dmabuf,
 309 };
 310
 311 struct drm_gem_object *i915_gem_prime_import(struct drm_device *dev,
 312                                              struct dma_buf *dma_buf)
 313 {
 314         struct dma_buf_attachment *attach;
 315         struct drm_i915_gem_object *obj;
 316         int ret;
 317
 318         /* is this one of own objects? */
 319         if (dma_buf->ops == &i915_dmabuf_ops) {
 320                 obj = dma_buf_to_obj(dma_buf);
 321                 /* is it from our device? */
 322                 if (obj->base.dev == dev) {
 323                         /*
 324                          * Importing dmabuf exported from out own gem increases
 325                          * refcount on gem itself instead of f_count of dmabuf.
 326                          */
 327                         drm_gem_object_reference(&obj->base);
 328                         return &obj->base;
 329                 }
 330         }
 331
 332         /* need to attach */
 333         attach = dma_buf_attach(dma_buf, dev->dev);
 334         if (IS_ERR(attach))
 335                 return ERR_CAST(attach);
 336
 337         get_dma_buf(dma_buf);
 338
 339         obj = i915_gem_object_alloc(dev);
 340         if (obj == NULL) {
 341                 ret = -ENOMEM;
 342                 goto fail_detach;
 343         }
 344
 345         drm_gem_private_object_init(dev, &obj->base, dma_buf->size);
 346         i915_gem_object_init(obj, &i915_gem_object_dmabuf_ops);
 347         obj->base.import_attach = attach;
 348
 349         return &obj->base;
 350
 351 fail_detach:
 352         dma_buf_detach(dma_buf, attach);
 353         dma_buf_put(dma_buf);
 354
 355         return ERR_PTR(ret);
 356 }