drivers/gpu/drm/exynos/exynos_drm_gem.c

   1 /* exynos_drm_gem.c
   2  *
   3  * Copyright (c) 2011 Samsung Electronics Co., Ltd.
   4  * Author: Inki Dae <inki.dae@samsung.com>
   5  *
   6  * This program is free software; you can redistribute  it and/or modify it
   7  * under  the terms of  the GNU General  Public License as published by the
   8  * Free Software Foundation;  either version 2 of the  License, or (at your
   9  * option) any later version.
  10  */
  11
  12 #include <drm/drmP.h>
  13 #include <drm/drm_vma_manager.h>
  14
  15 #include <linux/shmem_fs.h>
  16 #include <drm/exynos_drm.h>
  17
  18 #include "exynos_drm_drv.h"
  19 #include "exynos_drm_gem.h"
  20 #include "exynos_drm_buf.h"
  21 #include "exynos_drm_iommu.h"
  22
  23 static unsigned int convert_to_vm_err_msg(int msg)
  24 {
  25         unsigned int out_msg;
  26
  27         switch (msg) {
  28         case 0:
  29         case -ERESTARTSYS:
  30         case -EINTR:
  31                 out_msg = VM_FAULT_NOPAGE;
  32                 break;
  33
  34         case -ENOMEM:
  35                 out_msg = VM_FAULT_OOM;
  36                 break;
  37
  38         default:
  39                 out_msg = VM_FAULT_SIGBUS;
  40                 break;
  41         }
  42
  43         return out_msg;
  44 }
  45
  46 static int check_gem_flags(unsigned int flags)
  47 {
  48         if (flags & ~(EXYNOS_BO_MASK)) {
  49                 DRM_ERROR("invalid flags.\n");
  50                 return -EINVAL;
  51         }
  52
  53         return 0;
  54 }
  55
  56 static void update_vm_cache_attr(struct exynos_drm_gem_obj *obj,
  57                                         struct vm_area_struct *vma)
  58 {
  59         DRM_DEBUG_KMS("flags = 0x%x\n", obj->flags);
  60
  61         /* non-cachable as default. */
  62         if (obj->flags & EXYNOS_BO_CACHABLE)
  63                 vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);
  64         else if (obj->flags & EXYNOS_BO_WC)
  65                 vma->vm_page_prot =
  66                         pgprot_writecombine(vm_get_page_prot(vma->vm_flags));
  67         else
  68                 vma->vm_page_prot =
  69                         pgprot_noncached(vm_get_page_prot(vma->vm_flags));
  70 }
  71
  72 static unsigned long roundup_gem_size(unsigned long size, unsigned int flags)
  73 {
  74         /* TODO */
  75
  76         return roundup(size, PAGE_SIZE);
  77 }
  78
  79 static int exynos_drm_gem_map_buf(struct drm_gem_object *obj,
  80                                         struct vm_area_struct *vma,
  81                                         unsigned long f_vaddr,
  82                                         pgoff_t page_offset)
  83 {
  84         struct exynos_drm_gem_obj *exynos_gem_obj = to_exynos_gem_obj(obj);
  85         struct exynos_drm_gem_buf *buf = exynos_gem_obj->buffer;
  86         struct scatterlist *sgl;
  87         unsigned long pfn;
  88         int i;
  89
  90         if (!buf->sgt)
  91                 return -EINTR;
  92
  93         if (page_offset >= (buf->size >> PAGE_SHIFT)) {
  94                 DRM_ERROR("invalid page offset\n");
  95                 return -EINVAL;
  96         }
  97
  98         sgl = buf->sgt->sgl;
  99         for_each_sg(buf->sgt->sgl, sgl, buf->sgt->nents, i) {
 100                 if (page_offset < (sgl->length >> PAGE_SHIFT))
 101                         break;
 102                 page_offset -=  (sgl->length >> PAGE_SHIFT);
 103         }
 104
 105         pfn = __phys_to_pfn(sg_phys(sgl)) + page_offset;
 106
 107         return vm_insert_mixed(vma, f_vaddr, pfn);
 108 }
 109
 110 static int exynos_drm_gem_handle_create(struct drm_gem_object *obj,
 111                                         struct drm_file *file_priv,
 112                                         unsigned int *handle)
 113 {
 114         int ret;
 115
 116         /*
 117          * allocate a id of idr table where the obj is registered
 118          * and handle has the id what user can see.
 119          */
 120         ret = drm_gem_handle_create(file_priv, obj, handle);
 121         if (ret)
 122                 return ret;
 123
 124         DRM_DEBUG_KMS("gem handle = 0x%x\n", *handle);
 125
 126         /* drop reference from allocate - handle holds it now. */
 127         drm_gem_object_unreference_unlocked(obj);
 128
 129         return 0;
 130 }
 131
 132 void exynos_drm_gem_destroy(struct exynos_drm_gem_obj *exynos_gem_obj)
 133 {
 134         struct drm_gem_object *obj;
 135         struct exynos_drm_gem_buf *buf;
 136
 137         obj = &exynos_gem_obj->base;
 138         buf = exynos_gem_obj->buffer;
 139
 140         DRM_DEBUG_KMS("handle count = %d\n", obj->handle_count);
 141
 142         /*
 143          * do not release memory region from exporter.
 144          *
 145          * the region will be released by exporter
 146          * once dmabuf's refcount becomes 0.
 147          */
 148         if (obj->import_attach)
 149                 goto out;
 150
 151         exynos_drm_free_buf(obj->dev, exynos_gem_obj->flags, buf);
 152
 153 out:
 154         exynos_drm_fini_buf(obj->dev, buf);
 155         exynos_gem_obj->buffer = NULL;
 156
 157         drm_gem_free_mmap_offset(obj);
 158
 159         /* release file pointer to gem object. */
 160         drm_gem_object_release(obj);
 161
 162         kfree(exynos_gem_obj);
 163         exynos_gem_obj = NULL;
 164 }
 165
 166 unsigned long exynos_drm_gem_get_size(struct drm_device *dev,
 167                                                 unsigned int gem_handle,
 168                                                 struct drm_file *file_priv)
 169 {
 170         struct exynos_drm_gem_obj *exynos_gem_obj;
 171         struct drm_gem_object *obj;
 172
 173         obj = drm_gem_object_lookup(dev, file_priv, gem_handle);
 174         if (!obj) {
 175                 DRM_ERROR("failed to lookup gem object.\n");
 176                 return 0;
 177         }
 178
 179         exynos_gem_obj = to_exynos_gem_obj(obj);
 180
 181         drm_gem_object_unreference_unlocked(obj);
 182
 183         return exynos_gem_obj->buffer->size;
 184 }
 185
 186
 187 struct exynos_drm_gem_obj *exynos_drm_gem_init(struct drm_device *dev,
 188                                                       unsigned long size)
 189 {
 190         struct exynos_drm_gem_obj *exynos_gem_obj;
 191         struct drm_gem_object *obj;
 192         int ret;
 193
 194         exynos_gem_obj = kzalloc(sizeof(*exynos_gem_obj), GFP_KERNEL);
 195         if (!exynos_gem_obj)
 196                 return NULL;
 197
 198         exynos_gem_obj->size = size;
 199         obj = &exynos_gem_obj->base;
 200
 201         ret = drm_gem_object_init(dev, obj, size);
 202         if (ret < 0) {
 203                 DRM_ERROR("failed to initialize gem object\n");
 204                 kfree(exynos_gem_obj);
 205                 return NULL;
 206         }
 207
 208         DRM_DEBUG_KMS("created file object = 0x%x\n", (unsigned int)obj->filp);
 209
 210         return exynos_gem_obj;
 211 }
 212
 213 struct exynos_drm_gem_obj *exynos_drm_gem_create(struct drm_device *dev,
 214                                                 unsigned int flags,
 215                                                 unsigned long size)
 216 {
 217         struct exynos_drm_gem_obj *exynos_gem_obj;
 218         struct exynos_drm_gem_buf *buf;
 219         int ret;
 220
 221         if (!size) {
 222                 DRM_ERROR("invalid size.\n");
 223                 return ERR_PTR(-EINVAL);
 224         }
 225
 226         size = roundup_gem_size(size, flags);
 227
 228         ret = check_gem_flags(flags);
 229         if (ret)
 230                 return ERR_PTR(ret);
 231
 232         buf = exynos_drm_init_buf(dev, size);
 233         if (!buf)
 234                 return ERR_PTR(-ENOMEM);
 235
 236         exynos_gem_obj = exynos_drm_gem_init(dev, size);
 237         if (!exynos_gem_obj) {
 238                 ret = -ENOMEM;
 239                 goto err_fini_buf;
 240         }
 241
 242         exynos_gem_obj->buffer = buf;
 243
 244         /* set memory type and cache attribute from user side. */
 245         exynos_gem_obj->flags = flags;
 246
 247         ret = exynos_drm_alloc_buf(dev, buf, flags);
 248         if (ret < 0)
 249                 goto err_gem_fini;
 250
 251         return exynos_gem_obj;
 252
 253 err_gem_fini:
 254         drm_gem_object_release(&exynos_gem_obj->base);
 255         kfree(exynos_gem_obj);
 256 err_fini_buf:
 257         exynos_drm_fini_buf(dev, buf);
 258         return ERR_PTR(ret);
 259 }
 260
 261 int exynos_drm_gem_create_ioctl(struct drm_device *dev, void *data,
 262                                 struct drm_file *file_priv)
 263 {
 264         struct drm_exynos_gem_create *args = data;
 265         struct exynos_drm_gem_obj *exynos_gem_obj;
 266         int ret;
 267
 268         exynos_gem_obj = exynos_drm_gem_create(dev, args->flags, args->size);
 269         if (IS_ERR(exynos_gem_obj))
 270                 return PTR_ERR(exynos_gem_obj);
 271
 272         ret = exynos_drm_gem_handle_create(&exynos_gem_obj->base, file_priv,
 273                         &args->handle);
 274         if (ret) {
 275                 exynos_drm_gem_destroy(exynos_gem_obj);
 276                 return ret;
 277         }
 278
 279         return 0;
 280 }
 281
 282 dma_addr_t *exynos_drm_gem_get_dma_addr(struct drm_device *dev,
 283                                         unsigned int gem_handle,
 284                                         struct drm_file *filp)
 285 {
 286         struct exynos_drm_gem_obj *exynos_gem_obj;
 287         struct drm_gem_object *obj;
 288
 289         obj = drm_gem_object_lookup(dev, filp, gem_handle);
 290         if (!obj) {
 291                 DRM_ERROR("failed to lookup gem object.\n");
 292                 return ERR_PTR(-EINVAL);
 293         }
 294
 295         exynos_gem_obj = to_exynos_gem_obj(obj);
 296
 297         return &exynos_gem_obj->buffer->dma_addr;
 298 }
 299
 300 void exynos_drm_gem_put_dma_addr(struct drm_device *dev,
 301                                         unsigned int gem_handle,
 302                                         struct drm_file *filp)
 303 {
 304         struct exynos_drm_gem_obj *exynos_gem_obj;
 305         struct drm_gem_object *obj;
 306
 307         obj = drm_gem_object_lookup(dev, filp, gem_handle);
 308         if (!obj) {
 309                 DRM_ERROR("failed to lookup gem object.\n");
 310                 return;
 311         }
 312
 313         exynos_gem_obj = to_exynos_gem_obj(obj);
 314
 315         drm_gem_object_unreference_unlocked(obj);
 316
 317         /*
 318          * decrease obj->refcount one more time because we has already
 319          * increased it at exynos_drm_gem_get_dma_addr().
 320          */
 321         drm_gem_object_unreference_unlocked(obj);
 322 }
 323
 324 int exynos_drm_gem_map_offset_ioctl(struct drm_device *dev, void *data,
 325                                     struct drm_file *file_priv)
 326 {
 327         struct drm_exynos_gem_map_off *args = data;
 328
 329         DRM_DEBUG_KMS("handle = 0x%x, offset = 0x%lx\n",
 330                         args->handle, (unsigned long)args->offset);
 331
 332         if (!(dev->driver->driver_features & DRIVER_GEM)) {
 333                 DRM_ERROR("does not support GEM.\n");
 334                 return -ENODEV;
 335         }
 336
 337         return exynos_drm_gem_dumb_map_offset(file_priv, dev, args->handle,
 338                         &args->offset);
 339 }
 340
 341 static struct drm_file *exynos_drm_find_drm_file(struct drm_device *drm_dev,
 342                                                         struct file *filp)
 343 {
 344         struct drm_file *file_priv;
 345
 346         /* find current process's drm_file from filelist. */
 347         list_for_each_entry(file_priv, &drm_dev->filelist, lhead)
 348                 if (file_priv->filp == filp)
 349                         return file_priv;
 350
 351         WARN_ON(1);
 352
 353         return ERR_PTR(-EFAULT);
 354 }
 355
 356 static int exynos_drm_gem_mmap_buffer(struct file *filp,
 357                                       struct vm_area_struct *vma)
 358 {
 359         struct drm_gem_object *obj = filp->private_data;
 360         struct exynos_drm_gem_obj *exynos_gem_obj = to_exynos_gem_obj(obj);
 361         struct drm_device *drm_dev = obj->dev;
 362         struct exynos_drm_gem_buf *buffer;
 363         struct drm_file *file_priv;
 364         unsigned long vm_size;
 365         int ret;
 366
 367         vma->vm_flags |= VM_IO | VM_DONTEXPAND | VM_DONTDUMP;
 368         vma->vm_private_data = obj;
 369         vma->vm_ops = drm_dev->driver->gem_vm_ops;
 370
 371         /* restore it to driver's fops. */
 372         filp->f_op = fops_get(drm_dev->driver->fops);
 373
 374         file_priv = exynos_drm_find_drm_file(drm_dev, filp);
 375         if (IS_ERR(file_priv))
 376                 return PTR_ERR(file_priv);
 377
 378         /* restore it to drm_file. */
 379         filp->private_data = file_priv;
 380
 381         update_vm_cache_attr(exynos_gem_obj, vma);
 382
 383         vm_size = vma->vm_end - vma->vm_start;
 384
 385         /*
 386          * a buffer contains information to physically continuous memory
 387          * allocated by user request or at framebuffer creation.
 388          */
 389         buffer = exynos_gem_obj->buffer;
 390
 391         /* check if user-requested size is valid. */
 392         if (vm_size > buffer->size)
 393                 return -EINVAL;
 394
 395         ret = dma_mmap_attrs(drm_dev->dev, vma, buffer->pages,
 396                                 buffer->dma_addr, buffer->size,
 397                                 &buffer->dma_attrs);
 398         if (ret < 0) {
 399                 DRM_ERROR("failed to mmap.\n");
 400                 return ret;
 401         }
 402
 403         /*
 404          * take a reference to this mapping of the object. And this reference
 405          * is unreferenced by the corresponding vm_close call.
 406          */
 407         drm_gem_object_reference(obj);
 408
 409         drm_vm_open_locked(drm_dev, vma);
 410
 411         return 0;
 412 }
 413
 414 static const struct file_operations exynos_drm_gem_fops = {
 415         .mmap = exynos_drm_gem_mmap_buffer,
 416 };
 417
 418 int exynos_drm_gem_mmap_ioctl(struct drm_device *dev, void *data,
 419                               struct drm_file *file_priv)
 420 {
 421         struct drm_exynos_gem_mmap *args = data;
 422         struct drm_gem_object *obj;
 423         unsigned long addr;
 424
 425         if (!(dev->driver->driver_features & DRIVER_GEM)) {
 426                 DRM_ERROR("does not support GEM.\n");
 427                 return -ENODEV;
 428         }
 429
 430         obj = drm_gem_object_lookup(dev, file_priv, args->handle);
 431         if (!obj) {
 432                 DRM_ERROR("failed to lookup gem object.\n");
 433                 return -EINVAL;
 434         }
 435
 436         /*
 437          * We have to use gem object and its fops for specific mmaper,
 438          * but vm_mmap() can deliver only filp. So we have to change
 439          * filp->f_op and filp->private_data temporarily, then restore
 440          * again. So it is important to keep lock until restoration the
 441          * settings to prevent others from misuse of filp->f_op or
 442          * filp->private_data.
 443          */
 444         mutex_lock(&dev->struct_mutex);
 445
 446         /*
 447          * Set specific mmper's fops. And it will be restored by
 448          * exynos_drm_gem_mmap_buffer to dev->driver->fops.
 449          * This is used to call specific mapper temporarily.
 450          */
 451         file_priv->filp->f_op = &exynos_drm_gem_fops;
 452
 453         /*
 454          * Set gem object to private_data so that specific mmaper
 455          * can get the gem object. And it will be restored by
 456          * exynos_drm_gem_mmap_buffer to drm_file.
 457          */
 458         file_priv->filp->private_data = obj;
 459
 460         addr = vm_mmap(file_priv->filp, 0, args->size,
 461                         PROT_READ | PROT_WRITE, MAP_SHARED, 0);
 462
 463         drm_gem_object_unreference(obj);
 464
 465         if (IS_ERR_VALUE(addr)) {
 466                 /* check filp->f_op, filp->private_data are restored */
 467                 if (file_priv->filp->f_op == &exynos_drm_gem_fops) {
 468                         file_priv->filp->f_op = fops_get(dev->driver->fops);
 469                         file_priv->filp->private_data = file_priv;
 470                 }
 471                 mutex_unlock(&dev->struct_mutex);
 472                 return (int)addr;
 473         }
 474
 475         mutex_unlock(&dev->struct_mutex);
 476
 477         args->mapped = addr;
 478
 479         DRM_DEBUG_KMS("mapped = 0x%lx\n", (unsigned long)args->mapped);
 480
 481         return 0;
 482 }
 483
 484 int exynos_drm_gem_get_ioctl(struct drm_device *dev, void *data,
 485                                       struct drm_file *file_priv)
 486 {       struct exynos_drm_gem_obj *exynos_gem_obj;
 487         struct drm_exynos_gem_info *args = data;
 488         struct drm_gem_object *obj;
 489
 490         mutex_lock(&dev->struct_mutex);
 491
 492         obj = drm_gem_object_lookup(dev, file_priv, args->handle);
 493         if (!obj) {
 494                 DRM_ERROR("failed to lookup gem object.\n");
 495                 mutex_unlock(&dev->struct_mutex);
 496                 return -EINVAL;
 497         }
 498
 499         exynos_gem_obj = to_exynos_gem_obj(obj);
 500
 501         args->flags = exynos_gem_obj->flags;
 502         args->size = exynos_gem_obj->size;
 503
 504         drm_gem_object_unreference(obj);
 505         mutex_unlock(&dev->struct_mutex);
 506
 507         return 0;
 508 }
 509
 510 struct vm_area_struct *exynos_gem_get_vma(struct vm_area_struct *vma)
 511 {
 512         struct vm_area_struct *vma_copy;
 513
 514         vma_copy = kmalloc(sizeof(*vma_copy), GFP_KERNEL);
 515         if (!vma_copy)
 516                 return NULL;
 517
 518         if (vma->vm_ops && vma->vm_ops->open)
 519                 vma->vm_ops->open(vma);
 520
 521         if (vma->vm_file)
 522                 get_file(vma->vm_file);
 523
 524         memcpy(vma_copy, vma, sizeof(*vma));
 525
 526         vma_copy->vm_mm = NULL;
 527         vma_copy->vm_next = NULL;
 528         vma_copy->vm_prev = NULL;
 529
 530         return vma_copy;
 531 }
 532
 533 void exynos_gem_put_vma(struct vm_area_struct *vma)
 534 {
 535         if (!vma)
 536                 return;
 537
 538         if (vma->vm_ops && vma->vm_ops->close)
 539                 vma->vm_ops->close(vma);
 540
 541         if (vma->vm_file)
 542                 fput(vma->vm_file);
 543
 544         kfree(vma);
 545 }
 546
 547 int exynos_gem_get_pages_from_userptr(unsigned long start,
 548                                                 unsigned int npages,
 549                                                 struct page **pages,
 550                                                 struct vm_area_struct *vma)
 551 {
 552         int get_npages;
 553
 554         /* the memory region mmaped with VM_PFNMAP. */
 555         if (vma_is_io(vma)) {
 556                 unsigned int i;
 557
 558                 for (i = 0; i < npages; ++i, start += PAGE_SIZE) {
 559                         unsigned long pfn;
 560                         int ret = follow_pfn(vma, start, &pfn);
 561                         if (ret)
 562                                 return ret;
 563
 564                         pages[i] = pfn_to_page(pfn);
 565                 }
 566
 567                 if (i != npages) {
 568                         DRM_ERROR("failed to get user_pages.\n");
 569                         return -EINVAL;
 570                 }
 571
 572                 return 0;
 573         }
 574
 575         get_npages = get_user_pages(current, current->mm, start,
 576                                         npages, 1, 1, pages, NULL);
 577         get_npages = max(get_npages, 0);
 578         if (get_npages != npages) {
 579                 DRM_ERROR("failed to get user_pages.\n");
 580                 while (get_npages)
 581                         put_page(pages[--get_npages]);
 582                 return -EFAULT;
 583         }
 584
 585         return 0;
 586 }
 587
 588 void exynos_gem_put_pages_to_userptr(struct page **pages,
 589                                         unsigned int npages,
 590                                         struct vm_area_struct *vma)
 591 {
 592         if (!vma_is_io(vma)) {
 593                 unsigned int i;
 594
 595                 for (i = 0; i < npages; i++) {
 596                         set_page_dirty_lock(pages[i]);
 597
 598                         /*
 599                          * undo the reference we took when populating
 600                          * the table.
 601                          */
 602                         put_page(pages[i]);
 603                 }
 604         }
 605 }
 606
 607 int exynos_gem_map_sgt_with_dma(struct drm_device *drm_dev,
 608                                 struct sg_table *sgt,
 609                                 enum dma_data_direction dir)
 610 {
 611         int nents;
 612
 613         mutex_lock(&drm_dev->struct_mutex);
 614
 615         nents = dma_map_sg(drm_dev->dev, sgt->sgl, sgt->nents, dir);
 616         if (!nents) {
 617                 DRM_ERROR("failed to map sgl with dma.\n");
 618                 mutex_unlock(&drm_dev->struct_mutex);
 619                 return nents;
 620         }
 621
 622         mutex_unlock(&drm_dev->struct_mutex);
 623         return 0;
 624 }
 625
 626 void exynos_gem_unmap_sgt_from_dma(struct drm_device *drm_dev,
 627                                 struct sg_table *sgt,
 628                                 enum dma_data_direction dir)
 629 {
 630         dma_unmap_sg(drm_dev->dev, sgt->sgl, sgt->nents, dir);
 631 }
 632
 633 void exynos_drm_gem_free_object(struct drm_gem_object *obj)
 634 {
 635         struct exynos_drm_gem_obj *exynos_gem_obj;
 636         struct exynos_drm_gem_buf *buf;
 637
 638         exynos_gem_obj = to_exynos_gem_obj(obj);
 639         buf = exynos_gem_obj->buffer;
 640
 641         if (obj->import_attach)
 642                 drm_prime_gem_destroy(obj, buf->sgt);
 643
 644         exynos_drm_gem_destroy(to_exynos_gem_obj(obj));
 645 }
 646
 647 int exynos_drm_gem_dumb_create(struct drm_file *file_priv,
 648                                struct drm_device *dev,
 649                                struct drm_mode_create_dumb *args)
 650 {
 651         struct exynos_drm_gem_obj *exynos_gem_obj;
 652         int ret;
 653
 654         /*
 655          * alocate memory to be used for framebuffer.
 656          * - this callback would be called by user application
 657          *      with DRM_IOCTL_MODE_CREATE_DUMB command.
 658          */
 659
 660         args->pitch = args->width * ((args->bpp + 7) / 8);
 661         args->size = args->pitch * args->height;
 662
 663         exynos_gem_obj = exynos_drm_gem_create(dev, EXYNOS_BO_CONTIG |
 664                                                 EXYNOS_BO_WC, args->size);
 665         /*
 666          * If physically contiguous memory allocation fails and if IOMMU is
 667          * supported then try to get buffer from non physically contiguous
 668          * memory area.
 669          */
 670         if (IS_ERR(exynos_gem_obj) && is_drm_iommu_supported(dev)) {
 671                 dev_warn(dev->dev, "contiguous FB allocation failed, falling back to non-contiguous\n");
 672                 exynos_gem_obj = exynos_drm_gem_create(dev,
 673                                         EXYNOS_BO_NONCONTIG | EXYNOS_BO_WC,
 674                                         args->size);
 675         }
 676
 677         if (IS_ERR(exynos_gem_obj))
 678                 return PTR_ERR(exynos_gem_obj);
 679
 680         ret = exynos_drm_gem_handle_create(&exynos_gem_obj->base, file_priv,
 681                         &args->handle);
 682         if (ret) {
 683                 exynos_drm_gem_destroy(exynos_gem_obj);
 684                 return ret;
 685         }
 686
 687         return 0;
 688 }
 689
 690 int exynos_drm_gem_dumb_map_offset(struct drm_file *file_priv,
 691                                    struct drm_device *dev, uint32_t handle,
 692                                    uint64_t *offset)
 693 {
 694         struct drm_gem_object *obj;
 695         int ret = 0;
 696
 697         mutex_lock(&dev->struct_mutex);
 698
 699         /*
 700          * get offset of memory allocated for drm framebuffer.
 701          * - this callback would be called by user application
 702          *      with DRM_IOCTL_MODE_MAP_DUMB command.
 703          */
 704
 705         obj = drm_gem_object_lookup(dev, file_priv, handle);
 706         if (!obj) {
 707                 DRM_ERROR("failed to lookup gem object.\n");
 708                 ret = -EINVAL;
 709                 goto unlock;
 710         }
 711
 712         ret = drm_gem_create_mmap_offset(obj);
 713         if (ret)
 714                 goto out;
 715
 716         *offset = drm_vma_node_offset_addr(&obj->vma_node);
 717         DRM_DEBUG_KMS("offset = 0x%lx\n", (unsigned long)*offset);
 718
 719 out:
 720         drm_gem_object_unreference(obj);
 721 unlock:
 722         mutex_unlock(&dev->struct_mutex);
 723         return ret;
 724 }
 725
 726 int exynos_drm_gem_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
 727 {
 728         struct drm_gem_object *obj = vma->vm_private_data;
 729         struct drm_device *dev = obj->dev;
 730         unsigned long f_vaddr;
 731         pgoff_t page_offset;
 732         int ret;
 733
 734         page_offset = ((unsigned long)vmf->virtual_address -
 735                         vma->vm_start) >> PAGE_SHIFT;
 736         f_vaddr = (unsigned long)vmf->virtual_address;
 737
 738         mutex_lock(&dev->struct_mutex);
 739
 740         ret = exynos_drm_gem_map_buf(obj, vma, f_vaddr, page_offset);
 741         if (ret < 0)
 742                 DRM_ERROR("failed to map a buffer with user.\n");
 743
 744         mutex_unlock(&dev->struct_mutex);
 745
 746         return convert_to_vm_err_msg(ret);
 747 }
 748
 749 int exynos_drm_gem_mmap(struct file *filp, struct vm_area_struct *vma)
 750 {
 751         struct exynos_drm_gem_obj *exynos_gem_obj;
 752         struct drm_gem_object *obj;
 753         int ret;
 754
 755         /* set vm_area_struct. */
 756         ret = drm_gem_mmap(filp, vma);
 757         if (ret < 0) {
 758                 DRM_ERROR("failed to mmap.\n");
 759                 return ret;
 760         }
 761
 762         obj = vma->vm_private_data;
 763         exynos_gem_obj = to_exynos_gem_obj(obj);
 764
 765         ret = check_gem_flags(exynos_gem_obj->flags);
 766         if (ret) {
 767                 drm_gem_vm_close(vma);
 768                 drm_gem_free_mmap_offset(obj);
 769                 return ret;
 770         }
 771
 772         vma->vm_flags &= ~VM_PFNMAP;
 773         vma->vm_flags |= VM_MIXEDMAP;
 774
 775         update_vm_cache_attr(exynos_gem_obj, vma);
 776
 777         return ret;
 778 }