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         void *addr;
 112         int ret;
 113
 114         ret = i915_mutex_lock_interruptible(dev);
 115         if (ret)
 116                 return ERR_PTR(ret);
 117
 118         addr = i915_gem_object_pin_map(obj);
 119         mutex_unlock(&dev->struct_mutex);
 120
 121         return addr;
 122 }
 123
 124 static void i915_gem_dmabuf_vunmap(struct dma_buf *dma_buf, void *vaddr)
 125 {
 126         struct drm_i915_gem_object *obj = dma_buf_to_obj(dma_buf);
 127         struct drm_device *dev = obj->base.dev;
 128
 129         mutex_lock(&dev->struct_mutex);
 130         i915_gem_object_unpin_map(obj);
 131         mutex_unlock(&dev->struct_mutex);
 132 }
 133
 134 static void *i915_gem_dmabuf_kmap_atomic(struct dma_buf *dma_buf, unsigned long page_num)
 135 {
 136         return NULL;
 137 }
 138
 139 static void i915_gem_dmabuf_kunmap_atomic(struct dma_buf *dma_buf, unsigned long page_num, void *addr)
 140 {
 141
 142 }
 143 static void *i915_gem_dmabuf_kmap(struct dma_buf *dma_buf, unsigned long page_num)
 144 {
 145         return NULL;
 146 }
 147
 148 static void i915_gem_dmabuf_kunmap(struct dma_buf *dma_buf, unsigned long page_num, void *addr)
 149 {
 150
 151 }
 152
 153 static int i915_gem_dmabuf_mmap(struct dma_buf *dma_buf, struct vm_area_struct *vma)
 154 {
 155         struct drm_i915_gem_object *obj = dma_buf_to_obj(dma_buf);
 156         int ret;
 157
 158         if (obj->base.size < vma->vm_end - vma->vm_start)
 159                 return -EINVAL;
 160
 161         if (!obj->base.filp)
 162                 return -ENODEV;
 163
 164         ret = obj->base.filp->f_op->mmap(obj->base.filp, vma);
 165         if (ret)
 166                 return ret;
 167
 168         fput(vma->vm_file);
 169         vma->vm_file = get_file(obj->base.filp);
 170
 171         return 0;
 172 }
 173
 174 static int i915_gem_begin_cpu_access(struct dma_buf *dma_buf, enum dma_data_direction direction)
 175 {
 176         struct drm_i915_gem_object *obj = dma_buf_to_obj(dma_buf);
 177         struct drm_device *dev = obj->base.dev;
 178         int ret;
 179         bool write = (direction == DMA_BIDIRECTIONAL || direction == DMA_TO_DEVICE);
 180
 181         ret = i915_mutex_lock_interruptible(dev);
 182         if (ret)
 183                 return ret;
 184
 185         ret = i915_gem_object_set_to_cpu_domain(obj, write);
 186         mutex_unlock(&dev->struct_mutex);
 187         return ret;
 188 }
 189
 190 static int i915_gem_end_cpu_access(struct dma_buf *dma_buf, enum dma_data_direction direction)
 191 {
 192         struct drm_i915_gem_object *obj = dma_buf_to_obj(dma_buf);
 193         struct drm_device *dev = obj->base.dev;
 194         int ret;
 195
 196         ret = i915_mutex_lock_interruptible(dev);
 197         if (ret)
 198                 return ret;
 199
 200         ret = i915_gem_object_set_to_gtt_domain(obj, false);
 201         mutex_unlock(&dev->struct_mutex);
 202
 203         return ret;
 204 }
 205
 206 static const struct dma_buf_ops i915_dmabuf_ops =  {
 207         .map_dma_buf = i915_gem_map_dma_buf,
 208         .unmap_dma_buf = i915_gem_unmap_dma_buf,
 209         .release = drm_gem_dmabuf_release,
 210         .kmap = i915_gem_dmabuf_kmap,
 211         .kmap_atomic = i915_gem_dmabuf_kmap_atomic,
 212         .kunmap = i915_gem_dmabuf_kunmap,
 213         .kunmap_atomic = i915_gem_dmabuf_kunmap_atomic,
 214         .mmap = i915_gem_dmabuf_mmap,
 215         .vmap = i915_gem_dmabuf_vmap,
 216         .vunmap = i915_gem_dmabuf_vunmap,
 217         .begin_cpu_access = i915_gem_begin_cpu_access,
 218         .end_cpu_access = i915_gem_end_cpu_access,
 219 };
 220
 221 struct dma_buf *i915_gem_prime_export(struct drm_device *dev,
 222                                       struct drm_gem_object *gem_obj, int flags)
 223 {
 224         struct drm_i915_gem_object *obj = to_intel_bo(gem_obj);
 225         DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
 226
 227         exp_info.ops = &i915_dmabuf_ops;
 228         exp_info.size = gem_obj->size;
 229         exp_info.flags = flags;
 230         exp_info.priv = gem_obj;
 231
 232
 233         if (obj->ops->dmabuf_export) {
 234                 int ret = obj->ops->dmabuf_export(obj);
 235                 if (ret)
 236                         return ERR_PTR(ret);
 237         }
 238
 239         return dma_buf_export(&exp_info);
 240 }
 241
 242 static int i915_gem_object_get_pages_dmabuf(struct drm_i915_gem_object *obj)
 243 {
 244         struct sg_table *sg;
 245
 246         sg = dma_buf_map_attachment(obj->base.import_attach, DMA_BIDIRECTIONAL);
 247         if (IS_ERR(sg))
 248                 return PTR_ERR(sg);
 249
 250         obj->pages = sg;
 251         return 0;
 252 }
 253
 254 static void i915_gem_object_put_pages_dmabuf(struct drm_i915_gem_object *obj)
 255 {
 256         dma_buf_unmap_attachment(obj->base.import_attach,
 257                                  obj->pages, DMA_BIDIRECTIONAL);
 258 }
 259
 260 static const struct drm_i915_gem_object_ops i915_gem_object_dmabuf_ops = {
 261         .get_pages = i915_gem_object_get_pages_dmabuf,
 262         .put_pages = i915_gem_object_put_pages_dmabuf,
 263 };
 264
 265 struct drm_gem_object *i915_gem_prime_import(struct drm_device *dev,
 266                                              struct dma_buf *dma_buf)
 267 {
 268         struct dma_buf_attachment *attach;
 269         struct drm_i915_gem_object *obj;
 270         int ret;
 271
 272         /* is this one of own objects? */
 273         if (dma_buf->ops == &i915_dmabuf_ops) {
 274                 obj = dma_buf_to_obj(dma_buf);
 275                 /* is it from our device? */
 276                 if (obj->base.dev == dev) {
 277                         /*
 278                          * Importing dmabuf exported from out own gem increases
 279                          * refcount on gem itself instead of f_count of dmabuf.
 280                          */
 281                         return &i915_gem_object_get(obj)->base;
 282                 }
 283         }
 284
 285         /* need to attach */
 286         attach = dma_buf_attach(dma_buf, dev->dev);
 287         if (IS_ERR(attach))
 288                 return ERR_CAST(attach);
 289
 290         get_dma_buf(dma_buf);
 291
 292         obj = i915_gem_object_alloc(dev);
 293         if (obj == NULL) {
 294                 ret = -ENOMEM;
 295                 goto fail_detach;
 296         }
 297
 298         drm_gem_private_object_init(dev, &obj->base, dma_buf->size);
 299         i915_gem_object_init(obj, &i915_gem_object_dmabuf_ops);
 300         obj->base.import_attach = attach;
 301
 302         /* We use GTT as shorthand for a coherent domain, one that is
 303          * neither in the GPU cache nor in the CPU cache, where all
 304          * writes are immediately visible in memory. (That's not strictly
 305          * true, but it's close! There are internal buffers such as the
 306          * write-combined buffer or a delay through the chipset for GTT
 307          * writes that do require us to treat GTT as a separate cache domain.)
 308          */
 309         obj->base.read_domains = I915_GEM_DOMAIN_GTT;
 310         obj->base.write_domain = 0;
 311
 312         return &obj->base;
 313
 314 fail_detach:
 315         dma_buf_detach(dma_buf, attach);
 316         dma_buf_put(dma_buf);
 317
 318         return ERR_PTR(ret);
 319 }