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         dma_unmap_sg(attachment->dev, sg->sgl, sg->nents, dir);
  99         sg_free_table(sg);
 100         kfree(sg);
 101
 102         mutex_lock(&obj->base.dev->struct_mutex);
 103         i915_gem_object_unpin_pages(obj);
 104         mutex_unlock(&obj->base.dev->struct_mutex);
 105 }
 106
 107 static void *i915_gem_dmabuf_vmap(struct dma_buf *dma_buf)
 108 {
 109         struct drm_i915_gem_object *obj = dma_buf_to_obj(dma_buf);
 110         struct drm_device *dev = obj->base.dev;
 111         struct sg_page_iter sg_iter;
 112         struct page **pages;
 113         int ret, i;
 114
 115         ret = i915_mutex_lock_interruptible(dev);
 116         if (ret)
 117                 return ERR_PTR(ret);
 118
 119         if (obj->dma_buf_vmapping) {
 120                 obj->vmapping_count++;
 121                 goto out_unlock;
 122         }
 123
 124         ret = i915_gem_object_get_pages(obj);
 125         if (ret)
 126                 goto err;
 127
 128         i915_gem_object_pin_pages(obj);
 129
 130         ret = -ENOMEM;
 131
 132         pages = drm_malloc_ab(obj->base.size >> PAGE_SHIFT, sizeof(*pages));
 133         if (pages == NULL)
 134                 goto err_unpin;
 135
 136         i = 0;
 137         for_each_sg_page(obj->pages->sgl, &sg_iter, obj->pages->nents, 0)
 138                 pages[i++] = sg_page_iter_page(&sg_iter);
 139
 140         obj->dma_buf_vmapping = vmap(pages, i, 0, PAGE_KERNEL);
 141         drm_free_large(pages);
 142
 143         if (!obj->dma_buf_vmapping)
 144                 goto err_unpin;
 145
 146         obj->vmapping_count = 1;
 147 out_unlock:
 148         mutex_unlock(&dev->struct_mutex);
 149         return obj->dma_buf_vmapping;
 150
 151 err_unpin:
 152         i915_gem_object_unpin_pages(obj);
 153 err:
 154         mutex_unlock(&dev->struct_mutex);
 155         return ERR_PTR(ret);
 156 }
 157
 158 static void i915_gem_dmabuf_vunmap(struct dma_buf *dma_buf, void *vaddr)
 159 {
 160         struct drm_i915_gem_object *obj = dma_buf_to_obj(dma_buf);
 161         struct drm_device *dev = obj->base.dev;
 162
 163         mutex_lock(&dev->struct_mutex);
 164         if (--obj->vmapping_count == 0) {
 165                 vunmap(obj->dma_buf_vmapping);
 166                 obj->dma_buf_vmapping = NULL;
 167
 168                 i915_gem_object_unpin_pages(obj);
 169         }
 170         mutex_unlock(&dev->struct_mutex);
 171 }
 172
 173 static void *i915_gem_dmabuf_kmap_atomic(struct dma_buf *dma_buf, unsigned long page_num)
 174 {
 175         return NULL;
 176 }
 177
 178 static void i915_gem_dmabuf_kunmap_atomic(struct dma_buf *dma_buf, unsigned long page_num, void *addr)
 179 {
 180
 181 }
 182 static void *i915_gem_dmabuf_kmap(struct dma_buf *dma_buf, unsigned long page_num)
 183 {
 184         return NULL;
 185 }
 186
 187 static void i915_gem_dmabuf_kunmap(struct dma_buf *dma_buf, unsigned long page_num, void *addr)
 188 {
 189
 190 }
 191
 192 static int i915_gem_dmabuf_mmap(struct dma_buf *dma_buf, struct vm_area_struct *vma)
 193 {
 194         struct drm_i915_gem_object *obj = dma_buf_to_obj(dma_buf);
 195         int ret;
 196
 197         if (obj->base.size < vma->vm_end - vma->vm_start)
 198                 return -EINVAL;
 199
 200         if (!obj->base.filp)
 201                 return -ENODEV;
 202
 203         ret = obj->base.filp->f_op->mmap(obj->base.filp, vma);
 204         if (ret)
 205                 return ret;
 206
 207         fput(vma->vm_file);
 208         vma->vm_file = get_file(obj->base.filp);
 209
 210         return 0;
 211 }
 212
 213 static int i915_gem_begin_cpu_access(struct dma_buf *dma_buf, enum dma_data_direction direction)
 214 {
 215         struct drm_i915_gem_object *obj = dma_buf_to_obj(dma_buf);
 216         struct drm_device *dev = obj->base.dev;
 217         int ret;
 218         bool write = (direction == DMA_BIDIRECTIONAL || direction == DMA_TO_DEVICE);
 219
 220         ret = i915_mutex_lock_interruptible(dev);
 221         if (ret)
 222                 return ret;
 223
 224         ret = i915_gem_object_set_to_cpu_domain(obj, write);
 225         mutex_unlock(&dev->struct_mutex);
 226         return ret;
 227 }
 228
 229 static void i915_gem_end_cpu_access(struct dma_buf *dma_buf, enum dma_data_direction direction)
 230 {
 231         struct drm_i915_gem_object *obj = dma_buf_to_obj(dma_buf);
 232         struct drm_device *dev = obj->base.dev;
 233         struct drm_i915_private *dev_priv = to_i915(dev);
 234         bool was_interruptible;
 235         int ret;
 236
 237         mutex_lock(&dev->struct_mutex);
 238         was_interruptible = dev_priv->mm.interruptible;
 239         dev_priv->mm.interruptible = false;
 240
 241         ret = i915_gem_object_set_to_gtt_domain(obj, false);
 242
 243         dev_priv->mm.interruptible = was_interruptible;
 244         mutex_unlock(&dev->struct_mutex);
 245
 246         if (unlikely(ret))
 247                 DRM_ERROR("unable to flush buffer following CPU access; rendering may be corrupt\n");
 248 }
 249
 250 static const struct dma_buf_ops i915_dmabuf_ops =  {
 251         .map_dma_buf = i915_gem_map_dma_buf,
 252         .unmap_dma_buf = i915_gem_unmap_dma_buf,
 253         .release = drm_gem_dmabuf_release,
 254         .kmap = i915_gem_dmabuf_kmap,
 255         .kmap_atomic = i915_gem_dmabuf_kmap_atomic,
 256         .kunmap = i915_gem_dmabuf_kunmap,
 257         .kunmap_atomic = i915_gem_dmabuf_kunmap_atomic,
 258         .mmap = i915_gem_dmabuf_mmap,
 259         .vmap = i915_gem_dmabuf_vmap,
 260         .vunmap = i915_gem_dmabuf_vunmap,
 261         .begin_cpu_access = i915_gem_begin_cpu_access,
 262         .end_cpu_access = i915_gem_end_cpu_access,
 263 };
 264
 265 struct dma_buf *i915_gem_prime_export(struct drm_device *dev,
 266                                       struct drm_gem_object *gem_obj, int flags)
 267 {
 268         struct drm_i915_gem_object *obj = to_intel_bo(gem_obj);
 269         DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
 270
 271         exp_info.ops = &i915_dmabuf_ops;
 272         exp_info.size = gem_obj->size;
 273         exp_info.flags = flags;
 274         exp_info.priv = gem_obj;
 275
 276
 277         if (obj->ops->dmabuf_export) {
 278                 int ret = obj->ops->dmabuf_export(obj);
 279                 if (ret)
 280                         return ERR_PTR(ret);
 281         }
 282
 283         return dma_buf_export(&exp_info);
 284 }
 285
 286 static int i915_gem_object_get_pages_dmabuf(struct drm_i915_gem_object *obj)
 287 {
 288         struct sg_table *sg;
 289
 290         sg = dma_buf_map_attachment(obj->base.import_attach, DMA_BIDIRECTIONAL);
 291         if (IS_ERR(sg))
 292                 return PTR_ERR(sg);
 293
 294         obj->pages = sg;
 295         return 0;
 296 }
 297
 298 static void i915_gem_object_put_pages_dmabuf(struct drm_i915_gem_object *obj)
 299 {
 300         dma_buf_unmap_attachment(obj->base.import_attach,
 301                                  obj->pages, DMA_BIDIRECTIONAL);
 302 }
 303
 304 static const struct drm_i915_gem_object_ops i915_gem_object_dmabuf_ops = {
 305         .get_pages = i915_gem_object_get_pages_dmabuf,
 306         .put_pages = i915_gem_object_put_pages_dmabuf,
 307 };
 308
 309 struct drm_gem_object *i915_gem_prime_import(struct drm_device *dev,
 310                                              struct dma_buf *dma_buf)
 311 {
 312         struct dma_buf_attachment *attach;
 313         struct drm_i915_gem_object *obj;
 314         int ret;
 315
 316         /* is this one of own objects? */
 317         if (dma_buf->ops == &i915_dmabuf_ops) {
 318                 obj = dma_buf_to_obj(dma_buf);
 319                 /* is it from our device? */
 320                 if (obj->base.dev == dev) {
 321                         /*
 322                          * Importing dmabuf exported from out own gem increases
 323                          * refcount on gem itself instead of f_count of dmabuf.
 324                          */
 325                         drm_gem_object_reference(&obj->base);
 326                         return &obj->base;
 327                 }
 328         }
 329
 330         /* need to attach */
 331         attach = dma_buf_attach(dma_buf, dev->dev);
 332         if (IS_ERR(attach))
 333                 return ERR_CAST(attach);
 334
 335         get_dma_buf(dma_buf);
 336
 337         obj = i915_gem_object_alloc(dev);
 338         if (obj == NULL) {
 339                 ret = -ENOMEM;
 340                 goto fail_detach;
 341         }
 342
 343         drm_gem_private_object_init(dev, &obj->base, dma_buf->size);
 344         i915_gem_object_init(obj, &i915_gem_object_dmabuf_ops);
 345         obj->base.import_attach = attach;
 346
 347         return &obj->base;
 348
 349 fail_detach:
 350         dma_buf_detach(dma_buf, attach);
 351         dma_buf_put(dma_buf);
 352
 353         return ERR_PTR(ret);
 354 }